Sample records for tall obstacles nearby

  1. Tall building collapse mechanisms initiated by fire 

    E-Print Network [OSTI]

    Usmani, Asif; Roben, Charlotte; Johnston, Louise; Flint, Graeme

    This paper introduces the hypothesis of two possible failure mechanisms for tall buildings in multiple floor fires. This paper extends the previous work done on the WTC towers by investigating more "generic" tall building frames made of standard...

  2. Internal tide generation by tall ocean ridges

    E-Print Network [OSTI]

    Echeverri Mondragón, Paula

    2009-01-01T23:59:59.000Z

    Internal tides are internal waves of tidal period generated by tidal currents flowing over submarine topography. Tall ridges that are nominally two-dimensional (2-D) are sites of particularly strong generation. The subsequent ...

  3. Microsoft Word - Tall_Pines_CX.doc

    Broader source: Energy.gov (indexed) [DOE]

    Project Manager - KEWM-4 Proposed Action: Provision of funds to the Idaho Department of Fish and Game for purchase of the Tall Pines Property. Fish and Wildlife Project No.:...

  4. Apparatus for obstacle traversion

    DOE Patents [OSTI]

    Borenstein, Johann

    2004-08-10T23:59:59.000Z

    An apparatus for traversing obstacles having an elongated, round, flexible body that includes a plurality of drive track assemblies. The plurality of drive track assemblies cooperate to provide forward propulsion wherever a propulsion member is in contact with any feature of the environment, regardless of how many or which ones of the plurality of drive track assemblies make contact with such environmental feature.

  5. Dynamic interrelationship between technology and architecture in tall buildings

    E-Print Network [OSTI]

    Moon, Kyoung-Sun

    2005-01-01T23:59:59.000Z

    The interrelationship between the technology and architecture of tall buildings is investigated from the emergence of tall buildings in the late 19th century to the present. Through the historical research, a filtering ...

  6. Fire Induced Collapse of Tall Buildings 

    E-Print Network [OSTI]

    Flint, Graeme

    This research was designed to investigate possible mechanisms that fires could initiate that might lead to collapse of a tall building of similar design to the WTC Towers. It was not designed to be a forensic study and no initial damage was applied...

  7. Tall Corn Ethanol LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to:Holdings Co08.0 -TEEMP JumpTakigamiTalbotts LtdTall Corn

  8. Obstacle-avoiding navigation system

    DOE Patents [OSTI]

    Borenstein, Johann (Ann Arbor, MI); Koren, Yoram (Ann Arbor, MI); Levine, Simon P. (Ann Arbor, MI)

    1991-01-01T23:59:59.000Z

    A system for guiding an autonomous or semi-autonomous vehicle through a field of operation having obstacles thereon to be avoided employs a memory for containing data which defines an array of grid cells which correspond to respective subfields in the field of operation of the vehicle. Each grid cell in the memory contains a value which is indicative of the likelihood, or probability, that an obstacle is present in the respectively associated subfield. The values in the grid cells are incremented individually in response to each scan of the subfields, and precomputation and use of a look-up table avoids complex trigonometric functions. A further array of grid cells is fixed with respect to the vehicle form a conceptual active window which overlies the incremented grid cells. Thus, when the cells in the active window overly grid cell having values which are indicative of the presence of obstacles, the value therein is used as a multiplier of the precomputed vectorial values. The resulting plurality of vectorial values are summed vectorially in one embodiment of the invention to produce a virtual composite repulsive vector which is then summed vectorially with a target-directed vector for producing a resultant vector for guiding the vehicle. In an alternative embodiment, a plurality of vectors surrounding the vehicle are computed, each having a value corresponding to obstacle density. In such an embodiment, target location information is used to select between alternative directions of travel having low associated obstacle densities.

  9. Wind Shear Characteristics at Central Plains Tall Towers: Preprint

    SciTech Connect (OSTI)

    Schwartz, M.; Elliott, D.

    2006-06-01T23:59:59.000Z

    Conference paper for WindPower 2006 held June 4-7, 2006, in Pittsburgh, PA, describing the wind shear characteristics at tall tower sites in the Central Plains of the United States.

  10. Improved recovery of tall oil from black liquors

    SciTech Connect (OSTI)

    Zucker, J.

    1980-12-09T23:59:59.000Z

    Applying a d.c. of less than 15 V to acidified black liquor separates a significant amount of tall oil remaining in the black liquor sludge. An apparatus with graphite electrodes for this process is described.

  11. Process for tertiary oil recovery using tall oil pitch

    DOE Patents [OSTI]

    Radke, C.J.

    1983-07-25T23:59:59.000Z

    A process and compositions for enhancing the recovery of acid crudes are disclosed. The process involves injecting caustic solutions into the reservoir to maintain a pH of 11 to 13. The fluid contains an effective amount of multivalent cation for inhibiting alkaline silica dissolution with the reservoir. A tall oil pitch soap is added as a polymeric mobility control agent. (DMC)

  12. Travelling times in scattering by obstacles

    E-Print Network [OSTI]

    Lyle Noakes; Luchezar Stoyanov

    2014-09-29T23:59:59.000Z

    The paper deals with some problems related to recovering information about an obstacle in an Euclidean space from certain measurements of lengths of generalized geodesics in the exterior of the obstacle. The main result is that if two obstacles satisfy some generic regularity conditions and have (almost) the same traveling times, then the generalized geodesic flows in their exteriors are conjugate on the non-trapping part of their phase spaces with a time preserving conjugacy. In the case of a union of two strictly convex domains in the plane, a constructive algorithm is described to recover the obstacle from traveling times.

  13. NUMERICAL SOLUTION OF AN INVERSE OBSTACLE ...

    E-Print Network [OSTI]

    2015-01-26T23:59:59.000Z

    Consider the scattering of an arbitrary time-harmonic incident wave by a sound soft ... the method is simple, efficient, and stable to reconstruct the obstacle with ...

  14. Guaranteed avoidance of unpredictable, dynamically constrained obstacles using velocity obstacle sets

    E-Print Network [OSTI]

    Wu, Albert (Albert Puming)

    2011-01-01T23:59:59.000Z

    Dynamic obstacle avoidance is an important, ubiquitous, and often challenging problem for autonomous mobile robots. This thesis presents a new method to guarantee collision avoidance with respect to moving obstacles that ...

  15. Process for tertiary oil recovery using tall oil pitch

    DOE Patents [OSTI]

    Radke, Clayton J. (El Cerrito, CA)

    1985-01-01T23:59:59.000Z

    Compositions and process employing same for enhancing the recovery of residual acid crudes, particularly heavy crudes, by injecting a composition comprising caustic in an amount sufficient to maintain a pH of at least about 11, preferably at least about 13, and a small but effective amount of a multivalent cation for inhibiting alkaline silica dissolution with the reservoir. Preferably a tall oil pitch soap is included and particularly for the heavy crudes a polymeric mobility control agent.

  16. Prolongation technologies for campaign life of tall oven

    SciTech Connect (OSTI)

    Doko, Yoshiji; Saji, Takafumi; Kitayama, Yoshiteru; Yoshida, Shuhei [Sumitomo Metal Industries, Ltd., Kashima, Ibaraki (Japan). Kashima Steel Works

    1997-12-31T23:59:59.000Z

    In Kashima Steel Works, 25-year-old 7-meter-high coke ovens have damage on their walls. However, by using new methods of internal in-situ investigation, ceramic welding for the extended central and upper portions of coke ovens has prolonged the campaign life for over 40 years without large-scale hot repair. In this paper, introduction of these new methods, its application in Kashima and the policy of repairing the tall coke oven are reported.

  17. PARABOLIC OBSTACLE PROBLEMS APPLIED TO FINANCE A ...

    E-Print Network [OSTI]

    2006-03-07T23:59:59.000Z

    1. Introduction. 1.1. Background. The parabolic obstacle problem refers to finding the smallest supper-solution (for a given parabolic ... H. Shahgholian is supported by Swedish Research Council. 1 ...... MR MR2052937 (2005d:35276). [BD97].

  18. Statistics of dislocation pinning at localized obstacles

    SciTech Connect (OSTI)

    Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2014-10-14T23:59:59.000Z

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  19. Flame acceleration and DDT in channels with obstacles: Effect of obstacle spacing

    SciTech Connect (OSTI)

    Gamezo, Vadim N.; Oran, Elaine S. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 20375 (United States); Ogawa, Takanobu [Department of Mechanical Engineering, Seikei University, Kichijoji-Kitamachi, Musashino-shi, Tokyo, 180-8633 (Japan)

    2008-10-15T23:59:59.000Z

    We study flame acceleration and deflagration-to-detonation transition (DDT) in obstructed channels using 2D reactive Navier-Stokes numerical simulations. The energy release rate for the stoichiometric hydrogen-air mixture is modeled by one-step Arrhenius kinetics. Computations performed for channels with symmetrical and staggered obstacle configurations show two main effects of obstacle spacing S. First, more obstacles per unit length create more perturbations that increase the flame surface area more quickly, and therefore the flame speed grows faster. Second, DDT occurs more easily when the obstacle spacing is large enough for Mach stems to form between obstacles. These two effects are responsible for three different regimes of flame acceleration and DDT observed in simulations: (1) Detonation is ignited when a Mach stem formed by the diffracting shock reflecting from the side wall collides with an obstacle, (2) Mach stems do not form, and the detonation is not ignited, and (3) Mach stems do not form, but the leading shock becomes strong enough to ignite a detonation by direct collision with the top of an obstacle. Regime 3 is observed for small S and involves multiple isolated detonations that appear between obstacles and play a key role in final stages of flame and shock acceleration. For Regime 1 and staggered obstacle configurations, we observe resonance phenomena that significantly reduce the DDT time when S/2 is comparable to the channel width. Effects of imposed symmetry and stochasticity on DDT phenomena are also considered. (author)

  20. Nuclear Activity in Nearby Galaxies

    E-Print Network [OSTI]

    Thaisa Storchi-Bergmann

    1999-03-03T23:59:59.000Z

    I discuss some recent observational results in the research of nearby active galactic nuclei (AGN). These results cover three main topics: (i) evidences for the current paradigm for AGN's, which include a nuclear supermassive blackhole (SMBH) fed via an accretion disk; (ii) evidence that this paradigm may also apply to LINER's, the lowest luminous AGN's and to normal galaxies; (iii) evidences of how the fueling of the SMBH occurs and its relation to recent and intermediate age (10^6 to 10^8 yrs old) episodes of star formation.

  1. Foam flow around an obstacle: obstacle-wall interaction , B. Dollet2

    E-Print Network [OSTI]

    Cox, Simon

    two-dimensional (2D) foams, such as can be made by squeezing a foam between two glass plates soFoam flow around an obstacle: obstacle-wall interaction S.J. Cox1 , B. Dollet2 , F. Graner2 1- chanics, University of Wales Aberystwyth, Ceredigion SY23 3BZ, UK, e-mail: foams@aber.ac.uk 2 Spectrom

  2. Mechanism of collapse of tall steel moment frame buildings under earthquake excitation Swaminathan Krishnan1

    E-Print Network [OSTI]

    Krishnan, Swaminathan

    . Classical energy balance analysis shows that only long- period excitation imparts energy to tall buildings significant story-overlap, typically separated by just one story. It is shown that a simple work-energy tall steel buildings in the 1985 Mexico City earthquake, there has been sustained interest

  3. Aerodynamic Loads on Tall Buildings: Interactive Database Yin Zhou. M.ASCE1

    E-Print Network [OSTI]

    Kareem, Ahsan

    tools in commercial design practice. However, considering the cost and lead time needed for wind tunnel.M.ASCE2 ; and Ahsan Kareem, M.ASCE3 Abstract: Under the action of wind, tall buildings oscillate measurements on a host of isolated tall building models. Combined with the analysis procedure provided

  4. CELL BIOLOGY & MOLECULAR GENETICS Infection of Somatic Embryos of Tall Fescue with Acremonium coenophialum

    E-Print Network [OSTI]

    Parrott, Wayne

    by the endophyte naturally occurs in planta, attempts were made to duplicate this phenomenon in vitro. Callus of the interactions between tall fescue and its endophyte. TALL FESCUE is & pasture grass grown on 16 million ha in Canada and the southeastern USA (Bacon and Siegel, 1988). It is commonly infected with an endophytic

  5. Does a toxic fungal endophyte of tall fescue affect reproduction of

    E-Print Network [OSTI]

    Jamieson, Ian

    Does a toxic fungal endophyte of tall fescue affect reproduction of takahe on offshore islands? DOC. References 9 #12;4 Jamieson & Easton--Tall fescue-endophytes and takahe reproction on offshore islands Final of Conservation. This paper may be cited as: Jamieson, I.; Sydney Easton, H. 2002: Does a toxic fungal endophyte

  6. tall tower facility and instrumentation New coNstraiNts oN the Nitrous oxide budget of agricultural ecosystems

    E-Print Network [OSTI]

    Minnesota, University of

    tall tower facility and instrumentation New coNstraiNts oN the Nitrous oxide budget of agricultural approach involves multiple tunable diode laser (TDL) spectroscopy systems, a tall tower, automated chambers hectare. Measurements are also made at the tall tower trace gas observatory (TGO) located at RROC

  7. Numerical solution of an inverse obstacle scattering problem with ...

    E-Print Network [OSTI]

    Peijun Li

    2015-03-16T23:59:59.000Z

    Mar 5, 2015 ... the obstacle surface by using the near-field data. .... Let 1, 2 be two obstacles defined by the same base radius a and two surface functions f1, ...

  8. The role of the aerodynamic modifications of the shapes of tall buildings

    E-Print Network [OSTI]

    Lee, Jooeun, S.M. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    With the advances in technology, recent tall building design has undergone a shift to the free-style geometric forms in the exuberant and liberal atmosphere. As a height of the building increases, it is more susceptible ...

  9. FLUX MEASUREMENTS FROM A TALL TOWER IN A COMPLEX LANDSCAPE

    SciTech Connect (OSTI)

    Kurzeja, R.; Weber, A.; Chiswell, S.; Parker, M.

    2010-07-22T23:59:59.000Z

    The accuracy and representativeness of flux measurements from a tall tower in a complex landscape was assessed by examining the vertical and sector variability of the ratio of wind speed to momentum flux and the ratio of vertical advective to eddy flux of heat. The 30-60 m ratios were consistent with theoretical predictions which indicate well mixed flux footprints. Some variation with sector was observed that were consistent with upstream roughness. Vertical advection was negligible compared with vertical flux except for a few sectors at night. This implies minor influence from internal boundary layers. Flux accuracy is a function of sector and stability but 30-60 m fluxes were found to be generally representative of the surrounding landscape. This paper will study flux data from a 300 m tower, with 4 levels of instruments, in a complex landscape. The surrounding landscape will be characterized in terms of the variation in the ratio of mean wind speed to momentum flux as a function of height and wind direction. The importance of local advection will be assessed by comparing vertical advection with eddy fluxes for momentum and heat.

  10. Obstacle detection for autonomous navigation : an LDRD final report.

    SciTech Connect (OSTI)

    Padilla, Denise D.

    2004-03-01T23:59:59.000Z

    This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled 'Obstacle Detection for Autonomous Navigation'. The principal goal of this project was to develop a mathematical framework for obstacle detection. The framework provides a basis for solutions to many complex obstacle detection problems critical to successful autonomous navigation. Another goal of this project was to characterize sensing requirements in terms of physical characteristics of obstacles, vehicles, and terrain. For example, a specific vehicle traveling at a specific velocity over a specific terrain requires a sensor with a certain range of detection, resolution, field-of-view, and sufficient sensitivity to specific obstacle characteristics. In some cases, combinations of sensors were required to distinguish between different hazardous obstacles and benign terrain. In our framework, the problem was posed as a multidimensional, multiple-hypothesis, pattern recognition problem. Features were extracted from selected sensors that allow hazardous obstacles to be distinguished from benign terrain and other types of obstacles. Another unique thrust of this project was to characterize different terrain classes with respect to both positive (e.g., rocks, trees, fences) and negative (e.g., holes, ditches, drop-offs) obstacles. The density of various hazards per square kilometer was statistically quantified for different terrain categories (e.g., high desert, ponderosa forest, and prairie). This quantification reflects the scale, or size, and mobility of different types of vehicles. The tradeoffs between obstacle detection, position location, path planning, and vehicle mobility capabilities were also to be characterized.

  11. Imaging planets around nearby white dwarfs

    E-Print Network [OSTI]

    M. R. Burleigh; F. J. Clarke; S. T. Hodgkin

    2002-02-09T23:59:59.000Z

    We suggest that Jovian planets will survive the late stages of stellar evolution, and that white dwarfs will retain planetary systems in wide orbits (>5AU). Utilising evolutionary models for Jovian planets, we show that infra-red imaging with 8m class telescopes of suitable nearby white dwarfs should allow us to resolve and detect companions >3Mjup. Detection of massive planetary companions to nearby white dwarfs would prove that such objects can survive the final stages of stellar evolution, place constraints on the frequency of main sequence stars with planetary systems dynamically similar to our own and allow direct spectroscopic investigation of their composition and structure.

  12. Obstacle penetrating dynamic radar imaging system

    DOE Patents [OSTI]

    Romero, Carlos E. (Livermore, CA); Zumstein, James E. (Livermore, CA); Chang, John T. (Danville, CA); Leach, Jr.. Richard R. (Castro Valley, CA)

    2006-12-12T23:59:59.000Z

    An obstacle penetrating dynamic radar imaging system for the detection, tracking, and imaging of an individual, animal, or object comprising a multiplicity of low power ultra wideband radar units that produce a set of return radar signals from the individual, animal, or object, and a processing system for said set of return radar signals for detection, tracking, and imaging of the individual, animal, or object. The system provides a radar video system for detecting and tracking an individual, animal, or object by producing a set of return radar signals from the individual, animal, or object with a multiplicity of low power ultra wideband radar units, and processing said set of return radar signals for detecting and tracking of the individual, animal, or object.

  13. Chance-Constrained Optimal Path Planning with Obstacles

    E-Print Network [OSTI]

    Williams, Brian C.

    . Williams Abstract--Autonomous vehicles need to plan trajectories to a specified goal that avoid obstacles validation with an aircraft obstacle avoidance example. I. INTRODUCTION Path planning for autonomous vehicles approach plans the future probabilistic distribution of the vehicle state so that the probability

  14. Rapid Estimation of Damage to Tall Buildings Using Near Real-Time Earthquake and Archived Structural Simulations

    E-Print Network [OSTI]

    Tape, Carl

    Rapid Estimation of Damage to Tall Buildings Using Near Real-Time Earthquake and Archived Structural Simulations by Swaminathan Krishnan, Emanuele Casarotti, Jim Goltz, Chen Ji, Dimitri Komatitsch a new approach to rapidly estimate the damage to tall buildings immediately following a large earthquake

  15. Tall fescue (Festuca arundinacea Schreb.) is the pre-dominant forage species on over one million acres of

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    Fungal Endophyte While occasional negative responses of animals con- suming tall fescue were observed an endophyte because it is found within tissue and does not affect the outward appear- ance of the grass. In the scientific community, the tall fescue fungal endophyte was formerly known as Acremonium coenophialum, but has

  16. Ergopeptine Alkaloid Production by Endophytes in a Common Tall Fescue Genotype iN. s. Hill,* W.A. Parrott, and D. D. Pope

    E-Print Network [OSTI]

    Parrott, Wayne

    Ergopeptine Alkaloid Production by Endophytes in a Common Tall Fescue Genotype iN. s. Hill,* W the plantwithaddedvigor,developmentof endophyte-infectedtall fescuepopulationsthatareincapableof producingergopeptineal thatwasinfectedbytwodifferentendophyteisolatesthatexpress differentlevels of alkaloidswhenin theirhostplants.Endophyte- free tall fescueGenotypePDN2

  17. AUTHOR: Mitchell A. Pavao-Zuckerman, John C. Waller, Teri Ingle, and Henry A. TITLE: Methane Emissions of Beef Cattle Grazing Tall Fescue Pastures at Three

    E-Print Network [OSTI]

    Pavao-Zuckerman, Mitchell

    : Methane Emissions of Beef Cattle Grazing Tall Fescue Pastures at Three Levels of Endophyte Infestation.) is an important forage in the eastern United States. The toxic syndrome associated with the endophytic fungus taurus) on two pastures each of E+ tall fescue, of endophyte free (E-) tall fescue, of E+/E- (1:1 ratio

  18. Stand persistence of tall fescue pasture cultivars free of or infested with Acremonium coenophialum

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -1071, USA The endophytic fungus A. coenophialum in tall fescue (Festuca arundinacea) is associated of endophyte free (E-) cultivars leads to improved livestock performance, persistence and stress tolerance of E. Levels of endophyte infestation were monitored yearly and remained constant. Stand density, ground cover

  19. Endophyte symbiosis with tall fescue: how strong are the impacts on communities and ecosystems?

    E-Print Network [OSTI]

    Rudgers, Jennifer

    Review Endophyte symbiosis with tall fescue: how strong are the impacts on communities: Competition Herbivory Lolium arundinaceum MAXQ endophyte Neotyphodium coenophialum Predators Soil Trophc interactions a b s t r a c t We have investigated community and ecosystem consequences of endophyte symbiosis

  20. Nutrient composition of tall fescue pasture forage free of or infested with Acremonium coenophialum

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    with the endophytic fungus A. coenophialum is associated with substantial economic reduction in grazing livestock shown that the use of endophyte-free (E-) cultivars leads to improved cattle performance (increased weight gain, milk production, and conception rate) compared to endophyte infected (E+) tall fescue

  1. Peroxidase activity of perennial ryegrass and tall fescue seedlings artificially infected with endophytes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    with endophytes Walid Naffaaa Catherine Ravelb Nicole Boyer' Jean-Jacques Guillaumina a Unité de pathologie. The peroxidase activity of tall fescue cv. Clarine artificially infected with Neotyphodium coenophialum or with e-endophytes ryegrass cv. Vigor artificially infected with different e-endophytes. In contrast, artificial infection

  2. Lightning strikes to tall objects: Currents inferred from far electromagnetic fields versus directly measured currents

    E-Print Network [OSTI]

    Florida, University of

    -field-to-current conversion factor for lightning strikes to flat ground based on the transmission line model and (b currents on tall towers are used for testing the validity of field-to-current conversion equations [e on current measurement location (e.g., near the top or bottom of the tower) and on whether initial or largest

  3. Gone are the days of awkwardly angling your tall plastic water

    E-Print Network [OSTI]

    Baskaran, Mark

    Gone are the days of awkwardly angling your tall plastic water bottle under the rushing arc of the number of plastic water bottles saved from landfills.As of Oct.31, the station in the RFC alone has with Facilities Planning and Management, retrofitted six standard drinking fountains with new EZH2O water bottle

  4. Collapse scenarios of WTC 1 & 2 with extension to generic tall buildings 

    E-Print Network [OSTI]

    Usmani, Asif; Flint, Graeme; Jowsey, Allan; Roben, Charlotte; Torero, Jose L

    the collapse of the tall buildings of the World Trade Center (WTC) complex on September 11, 2001 following the terrorist attacks that day. The aim of these analyses has no been to carry out a “forensic” investigation (as this was done by official US government...

  5. The Use of Tall Tower Field Data for Estimating Wind Turbine Power Performance , J. Chapman1

    E-Print Network [OSTI]

    Manuel, Lance

    The Use of Tall Tower Field Data for Estimating Wind Turbine Power Performance A. Swift1 , J data acquisition tower is continuously measuring and recording atmospheric conditions at multiple providing barometric pressure and temperature data. A second data acquisition tower approximately 100m

  6. The relevance of didactic categories for analysing obstacles in conceptual change

    E-Print Network [OSTI]

    Prediger, Susanne

    1 The relevance of didactic categories for analysing obstacles in conceptual change Revisiting research like `Grundvorstellungen' and epistemological obstacles. These didactic categories help to make

  7. An obstacle-based probabilistic roadmap method for path planning 

    E-Print Network [OSTI]

    Wu, Yan

    1996-01-01T23:59:59.000Z

    This thesis presents a new obstacle-based probabilistic roadmap method for motion planning for many degree of freedom robots that can be used to obtain high quality roadmaps even when the robot's configuration space is ...

  8. Chance-Constrained Optimal Path Planning With Obstacles

    E-Print Network [OSTI]

    Blackmore, Lars

    Autonomous vehicles need to plan trajectories to a specified goal that avoid obstacles. For robust execution, we must take into account uncertainty, which arises due to uncertain localization, modeling errors, and disturbances. ...

  9. ENERGY INFRASTRUCTURE SURVIVABILITY, INHERENT LIMITATIONS, OBSTACLES AND MITIGATION STRATEGIES

    E-Print Network [OSTI]

    Krings, Axel W.

    ENERGY INFRASTRUCTURE SURVIVABILITY, INHERENT LIMITATIONS, OBSTACLES AND MITIGATION STRATEGIES technologically complex society makes our homeland security even more vulnerable. Therefore, knowing how vulnerable such systems are is essential to improving their intrinsic reliability/survivability (in

  10. An obstacle-based probabilistic roadmap method for path planning

    E-Print Network [OSTI]

    Wu, Yan

    1996-01-01T23:59:59.000Z

    This thesis presents a new obstacle-based probabilistic roadmap method for motion planning for many degree of freedom robots that can be used to obtain high quality roadmaps even when the robot's configuration space is crowded. The main novelty...

  11. Obstacles to global CO? trading : a familiar problem

    E-Print Network [OSTI]

    Ellerman, A. Denny.

    There are many obstacles to the development of an international CO? emissions trading system, but the biggest is a feature that is often assumed: the existence of a single national system. Once a national system is in ...

  12. A contribution to urbanism--the tall building as a multi-dimensional framework for additive growth and change

    E-Print Network [OSTI]

    Nelson, David J. (David Jeffrey)

    1987-01-01T23:59:59.000Z

    Skyscrapers do not destroy cities; they make them look different and they make the urban space more crowded, but they have not yet put an end to the urban environment. Many of the problems with the early tall buildings ...

  13. Chemical characterization of acidic components in a commercial depitching of crude tall oil

    E-Print Network [OSTI]

    Tsurumi, Toshio

    1982-01-01T23:59:59.000Z

    observations were made in the examination of the composition of the tall oil fractions by GC-MS analyses, some of which have not been previously reported. Pal ustr ic acid 1s one of the major resin acid found 1n tall oil. The correspond1ng spectrum.... 59 316 5. 69 382 0. 31 (167) 0. 01 316 10. 92 314 4. 56 14:0 Myr 15:0 ai 16:0 Pal 17:0 ai (17:0) 18:0 18:0 Stea 18:1 Ole 18:2 18:2 Lin 18:3 Linn 20:0 18:2 18:2 18:2 18:2 18:2 conj 18:3 20:2 Seco +22: 0 P Sec o SA PAL...

  14. Managing stormwater in Watertown, MA : overcoming obstacles to change

    E-Print Network [OSTI]

    Chai, Shutsu K. (Shutsu Kindness)

    2009-01-01T23:59:59.000Z

    As effective imperviousness increases with urbanization, the impacts of stormwater runoff on local water systems and aquatic life are more and more deleterious. Stormwater runoff carries pollutants into nearby water bodies, ...

  15. THE ACS NEARBY GALAXY SURVEY TREASURY

    SciTech Connect (OSTI)

    Dalcanton, Julianne J.; Williams, Benjamin F.; Rosema, Keith; Gogarten, Stephanie M.; Christensen, Charlotte; Gilbert, Karoline; Hodge, Paul [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dolphin, Andrew [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger St., Las Cruces, NM 88003 (United States); Skillman, Evan D.; Weisz, Daniel [Department of Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States); Cole, Andrew [School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania (Australia); Girardi, Leo [Osservatorio Astronomico di Padova - INAF, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Karachentsev, Igor D. [Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnji Arkhyz, Karachai-Circessia Republic 369167 (Russian Federation); Olsen, Knut [NOAO, National Optical Astronomy Observatory 950 N. Cherry Ave., Tucson, AZ 85719 (United States); Freeman, Ken [Mount Stromlo Observatory, Research School of Astronomy and Astrophysics, The Australian National Univ., ACT 0200 (Australia); Gallart, Carme [Inst. de AstrofIsica de Canarias, VIa Lactea, s/n, 38200 La Laguna, Tenerife (Spain); Harris, Jason [Steward Observatory, Univ. of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); De Jong, Roelof S. [Space Telescope Science Inst., 3700 San Martin Dr., Baltimore, MD 21218 (United States)], E-mail: jd@astro.washington.edu, E-mail: ben@astro.washington.edu, E-mail: krosema@astro.washington.edu, E-mail: stephanie@astro.washington.edu, E-mail: christensen@astro.washington.edu, E-mail: fabio@astro.washington.edu, E-mail: trq@astro.washington.edu, E-mail: aseth@cfa.harvard.edu (and others)

    2009-07-15T23:59:59.000Z

    The ACS Nearby Galaxy Survey Treasury (ANGST) is a systematic survey to establish a legacy of uniform multi-color photometry of resolved stars for a volume-limited sample of nearby galaxies (D < 4 Mpc). The survey volume encompasses 69 galaxies in diverse environments, including close pairs, small and large groups, filaments, and truly isolated regions. The galaxies include a nearly complete range of morphological types spanning a factor of {approx}10{sup 4} in luminosity and star formation rate. The survey data consist of images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST), supplemented with archival data and new Wide Field Planetary Camera 2 (WFPC2) imaging taken after the failure of ACS. Survey images include wide field tilings covering the full radial extent of each galaxy, and single deep pointings in uncrowded regions of the most massive galaxies in the volume. The new wide field imaging in ANGST reaches median 50% completenesses of m {sub F475W} = 28.0 mag, m {sub F606W} = 27.3 mag, and m {sub F814W} = 27.3 mag, several magnitudes below the tip of the red giant branch (TRGB). The deep fields reach magnitudes sufficient to fully resolve the structure in the red clump. The resulting photometric catalogs are publicly accessible and contain over 34 million photometric measurements of >14 million stars. In this paper we present the details of the sample selection, imaging, data reduction, and the resulting photometric catalogs, along with an analysis of the photometric uncertainties (systematic and random), for both ACS and WFPC2 imaging. We also present uniformly derived relative distances measured from the apparent magnitude of the TRGB.

  16. Reverse Time Migration for Extended Obstacles: Acoustic Waves

    E-Print Network [OSTI]

    Junqing Chen; Zhiming Chen; Guanghui Huang

    2014-06-10T23:59:59.000Z

    We consider the resolution of the single frequency reverse time migration (RTM) method for extended targets without the assumption of the validation of geometric optics approximation. The resolution analysis, which applies in both penetrable and non-penetrable obstacles with sound soft or impedance boundary condition on the boundary of the obstacle, implies that the imaginary part of the cross-correlation imaging functional is always positive and thus may have better stability properties. Numerical experiments are included to illustrate the powerful imaging quality and to confirm our resolution results.

  17. Magnetic Wall Climbing Robot for Thin Surfaces with Specific Obstacles

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Magnetic Wall Climbing Robot for Thin Surfaces with Specific Obstacles W. Fischer¹, F. Tâche high magnetic forces The main optimization criterion for this robot was to design it as light@ethz.ch Summary. This paper describes a novel solution to a mobile climbing robot on mag- netic wheels, designed

  18. Recovering a polyhedral obstacle by a few backscattering measurements

    E-Print Network [OSTI]

    Jingzhi Li; Hongyu Liu

    2015-02-04T23:59:59.000Z

    We propose an inverse scattering scheme of recovering a polyhedral obstacle in $\\mathbb{R}^n$, $n=2,3$, by only a few high-frequency acoustic backscattering measurements. The obstacle could be sound-soft or sound-hard. It is shown that the modulus of the far-field pattern in the backscattering aperture possesses a certain local maximum behavior, from which one can determine the exterior normal directions of the front sides/faces. Then by using the phaseless backscattering data corresponding to a few incident plane waves with suitably chosen incident directions, one can determine the exterior unit normal vector of each side/face of the obstacle. After the determination of the exterior unit normals, the recovery is reduced to a finite-dimensional problem of determining a location point of the obstacle and the distance of each side/face away from the location point. For the latter reconstruction, we need make use of the far-field data with phases. Numerical experiments are also presented to illustrate the effectiveness of the proposed scheme.

  19. RESIDUAL TYPE A POSTERIORI ERROR ESTIMATES FOR ELLIPTIC OBSTACLE PROBLEMS

    E-Print Network [OSTI]

    Nochetto, Ricardo H.

    to double obstacle problems are briefly discussed. Key words. a posteriori error estimates, residual Science Foundation under the grant No.19771080 and China National Key Project ``Large Scale Scientific\\Gamma satisfies / Ÿ 0 on @ and K is the convex set of admissible displacements K := fv 2 H 1 0(\\Omega\\Gamma : v

  20. Obstacle Avoidance Control of Humanoid Robot Arm through Tactile Interaction

    E-Print Network [OSTI]

    Tachi, Susumu

    Obstacle Avoidance Control of Humanoid Robot Arm through Tactile Interaction Dzmitry Tsetserukou through tactile interaction. The implementation of the approach was realized on humanoid robot arm control are summarized and illustrated in this work as well. The controllable compliance of robot arm

  1. Flocking with Obstacle Avoidance in Switching Networks of Interconnected Vehicles

    E-Print Network [OSTI]

    Tanner, Herbert G.

    Flocking with Obstacle Avoidance in Switching Networks of Interconnected Vehicles Herbert G. Tanner Mechanical Engineering Department University of New Mexico Abstract--The paper introduces a set of nonsmooth- tivity requirements on the interconnection network can be relaxed due to the common objective. I

  2. A Probabilistic Approach to Optimal Robust Path Planning with Obstacles

    E-Print Network [OSTI]

    Williams, Brian C.

    and Brian Williams Abstract-- Autonomous vehicles need to plan trajectories to a specified goal that avoid of aircraft obstacle avoidance scenarios. I. INTRODUCTION Path planning for autonomous vehicles the future probabilistic distribution of the vehicle state so that the probability of collision

  3. Deterministic separation of suspended particles in a reconfigurable obstacle array

    E-Print Network [OSTI]

    Du, Siqi

    2015-01-01T23:59:59.000Z

    We use a macromodel of a flow-driven deterministic lateral displacement (DLD) microfluidic system to investigate conditions leading to size-separation of suspended particles. This model system can be easily reconfigured to establish an arbitrary orientation between the average flow field and the array of obstacles comprising the stationary phase (forcing angle). We also investigate the effect of obstacle size using two arrays with different obstacles but same surface-to-surface distance between them. In all cases, we observe the presence of a locked mode at small forcing angles, in which particles move along a principal direction in the lattice until a locked-to-zigzag transition takes place when the driving force reaches a critical angle. We show that the transition occurs at increasing angles for larger particles, thus enabling particle separation at specific forcing angles. Moreover, we observe a linear correlation between the critical angle and the size of the particles that could be used in the design of...

  4. The Photometric Properties of Nearby Type Ia Supernovae

    E-Print Network [OSTI]

    Ganeshalingam, Mohan

    2012-01-01T23:59:59.000Z

    The Rise-Time Distribution of Nearby Type Ia Supernovae 3.1Highlight: The Physics of Supernovae, ed. W. Hillebrandt &1.1 Supernovae . . . . . . . . . . . . . . 1.1.1

  5. HighwayForestCoast Inside City Tall BuildingStreetOpenCountryMountain Oliva and Torralba, 2001

    E-Print Network [OSTI]

    Xiao, Jianxiong

    HighwayForestCoast Inside City Tall BuildingStreetOpenCountryMountain Oliva and Torralba, 2001 or designed several state-of-art features that are potentially useful for scene classification, and several cellar barrel storage discotheque harbor classroom electrical substation (74%) industrial area oil

  6. Seasonal development of ozone-induced foliar injury on tall milkweed (Asclepias exaltata) in Great Smoky Mountains National Park

    E-Print Network [OSTI]

    Neufeld, Howard S.

    Seasonal development of ozone-induced foliar injury on tall milkweed (Asclepias exaltata) in Great by symptoms of foliar ozone injury. Abstract The goals of this study were to document the development of ozone-induced foliar injury, on a leaf-by-leaf basis, and to develop ozone exposure relationships for leaf cohorts

  7. ROFESSOR SUSAN J SMITH doesn't look like a radical. Tall, elegant and softly spoken she

    E-Print Network [OSTI]

    26 CAM 59 #12;P ROFESSOR SUSAN J SMITH doesn't look like a radical. Tall, elegant and softly spoken she might be, but under that calm exterior, Professor Smith has a startling ­ and seemingly highly, Susan J Smith (the initial, she says, essential in a world dictated by Google) rather enjoys swimming

  8. Measurements of Atmospheric O2 Variations at the WLEF Tall-tower Site Figure 4. Comparison to

    E-Print Network [OSTI]

    Stephens, Britton B.

    adapted a commercially available fuel-cell detector to make the first atmospheric O2 measurements from. The fuel-cell instrument has successfully measured O2 concentrations at the WLEF tall-tower research site in Environmental Sciences, CU, Boulder, Colorado, 2 NOAA Climate Monitoring and Diagnostics Laboratory, Boulder

  9. Kinematic segregation of nearby disk stars from the Hipparcos database

    E-Print Network [OSTI]

    R. E. de Souza; R. Teixeira

    2007-04-25T23:59:59.000Z

    To better understand our Galaxy, we investigate the pertinency of describing the sys tem of nearby disk stars in terms of a two-components Schwarzschild velocity distributio n.Using the proper motion and parallax information of Hipparcos database, we determine t he parameters characterizing the local stellar velocity field of a sample of 22000 disk stars. The sample we use is essentially the same as the one described by the criteria ad opted to study the LSR and the stream motion of the nearby stellar population

  10. 3-amino thioacridone inhibits DNA synthesis and induces DNA damage in T-cell acute lymphoblastic leukemia (T-ALL) in a p16-dependent manner

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    sequential therapy of acute leukemia with flavopiridol: indamage in T-cell acute lymphoblastic leukemia (T-ALL) in aT-lineage acute lymphoblastic leukemia. Blood 91:735-746,

  11. 3-amino thioacridone inhibits DNA synthesis and induces DNA damage in T-cell acute lymphoblastic leukemia (T-ALL) in a p16-dependent manner

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    T-lineage acute lymphoblastic leukemia. Blood 91:735-746,damage in T-cell acute lymphoblastic leukemia (T-ALL) in arelapse in T-cell acute lymphoblastic leukemia patients with

  12. Cumulative effects in Swedish EIA practice - difficulties and obstacles

    SciTech Connect (OSTI)

    Waernbaeck, Antoienette [Swedish EIA Centre, Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Uppsala (Sweden)], E-mail: antoienette.warnback@sol.slu.se; Hilding-Rydevik, Tuija [Swedish EIA Centre, Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Uppsala (Sweden)

    2009-02-15T23:59:59.000Z

    The importance of considering cumulative effects (CE) in the context of environmental assessment is manifested in the EU regulations. The demands on the contents of Environmental Impact Assessment (EIA) and Strategic Environmental Assessment (SEA) documents explicitly ask for CE to be described. In Swedish environmental assessment documents CE are rarely described or included. The aim of this paper is to look into the reasons behind this fact in the Swedish context. The paper describes and analyse how actors implementing the EIA and SEA legislation in Sweden perceive the current situation in relation to the legislative demands and the inclusion of cumulative effects. Through semi-structured interviews the following questions have been explored: Is the phenomenon of CE discussed and included in the EIA/SEA process? What do the actors include in and what is their knowledge of the term and concept of CE? Which difficulties and obstacles do these actors experience and what possibilities for inclusion of CE do they see in the EIA/SEA process? A large number of obstacles and hindrances emerged from the interviews conducted. It can be concluded from the analysis that the will to act does seem to exist. A lack of knowledge in respect of how to include cumulative effects and a lack of clear regulations concerning how this should be done seem to be perceived as the main obstacles. The knowledge of the term and the phenomenon is furthermore quite narrow and not all encompassing. They experience that there is a lack of procedures in place. They also seem to lack knowledge of methods in relation to how to actually work, in practice, with CE and how to include CE in the EIA/SEA process. It can be stated that the existence of this poor picture in relation to practice concerning CE in the context of impact assessment mirrors the existing and so far rather vague demands in respect of the inclusion and assessment of CE in Swedish EIA and SEA legislation, regulations, guidelines and handbooks.

  13. Motions of galaxies in the nearby universe with 2MASS

    E-Print Network [OSTI]

    Crook, Aidan Christopher

    2009-01-01T23:59:59.000Z

    I present the first model of a flow-field in the nearby Universe (cz < 12, 000 km s-') constructed from groups of galaxies identified in an all-sky flux-limited survey. The Two Micron All-Sky Redshift Survey (2MRS), upon ...

  14. Lyapunov indices with two nearby trajectories in a curved spacetime

    E-Print Network [OSTI]

    Xin Wu; Tian-Yi Huang; Hong Zhang

    2010-06-28T23:59:59.000Z

    We compare three methods for computing invariant Lyapunov exponents (LEs) in general relativity. They involve the geodesic deviation vector technique (M1), the two-nearby-orbits method with projection operations and with coordinate time as an independent variable (M2), and the two-nearby-orbits method without projection operations and with proper time as an independent variable (M3). An analysis indicates that M1 and M3 do not need any projection operation. In general, the values of LEs from the three methods are almost the same. As an advantage, M3 is simpler to use than M2. In addition, we propose to construct the invariant fast Lyapunov indictor (FLI) with two-nearby-trajectories and give its algorithm in order to quickly distinguish chaos from order. Taking a static axisymmetric spacetime as a physical model, we apply the invariant FLIs to explore the global dynamics of phase space of the system where regions of chaos and order are clearlyidentified.

  15. Lyapunov indices with two nearby trajectories in a curved spacetime

    SciTech Connect (OSTI)

    Wu, X. [Department of Physics, Nanchang University, Nanchang 330047 (China); Department of Astronomy, Nanjing University, Nanjing 210093 (China); Huang, T.-Y.; Zhang, H. [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

    2006-10-15T23:59:59.000Z

    We compare three methods for computing invariant Lyapunov exponents (LEs) in general relativity. These methods involve the geodesic deviation vector technique (M1), the two-nearby-orbits method with projection operations and with coordinate time as the independant variable (M2), and the two-nearby-orbits method without projection operations and with proper time as the independent variable (M3). An analysis indicates that M1 and M3 do not need any projection operation. In general, the values of LEs from the three methods are almost the same. However, M2 fails for some specific cases. As a result, M3 is the most preferable to calculate LEs in most cases. In addition, we propose to construct the invariant fast Lyapunov indictor (FLI) with two-nearby-trajectories and give its algorithm in order to quickly distinguish chaos from order. Taking a static axisymmetric spacetime as a physical model, we apply different algorithms of the FLI to explore the global dynamics of phase space of the system where regions of chaos and order are clearly identified.

  16. Damage to nearby divertor components of ITER-like devices during giant ELMs and disruptions

    E-Print Network [OSTI]

    Harilal, S. S.

    Damage to nearby divertor components of ITER-like devices during giant ELMs and disruptions. Fusion 50 (2010) 115004 (7pp) doi:10.1088/0029-5515/50/11/115004 Damage to nearby divertor components. The simulation results of the integrated modelling indicate a significant potential damage of the divertor nearby

  17. Sensor integration for implementation of obstacle avoidance in an autonomous helicopter system

    E-Print Network [OSTI]

    Mentzer, Christopher Isaac

    2006-08-16T23:59:59.000Z

    This thesis describes the development of the Texas A&M University Autonomous Helicopter System and the integration of obstacle avoidance capabilities into that system. The helicopter system, composed of a Bergen Observer helicopter and a Rotomotion...

  18. Multi-layer approach to motion planning in obstacle rich environment 

    E-Print Network [OSTI]

    Kim, Sung Hyun

    2009-05-15T23:59:59.000Z

    obstacle-rich environments. This research has led to the development of the multilayer trajectory generation approach. It is built on the principle of separation of concerns, which partitions a given problem into multiple independent layers, and addresses...

  19. Obstacles to Teaching in the Face of Academic Diversity: Implcations for Planning for Students with Disabilities

    E-Print Network [OSTI]

    Lenz, B. Keith; Kissam, Brenda; Bulgren, Janis; Melvin, Jeff; Roth, Janet

    1992-08-01T23:59:59.000Z

    This study was a collaborative project the incorporated the concerns and insights of 52 secondary science and social studies teachers in identifying the major obstacles in planning to teach academically diverse groups of ...

  20. Multi-layer approach to motion planning in obstacle rich environment

    E-Print Network [OSTI]

    Kim, Sung Hyun

    2009-05-15T23:59:59.000Z

    obstacle-rich environments. This research has led to the development of the multilayer trajectory generation approach. It is built on the principle of separation of concerns, which partitions a given problem into multiple independent layers, and addresses...

  1. http://www.staradvertiser.com/newspremium/20130824_Small_school_stands_tall_as_science_powerhouse_.html?id=220927791&c=n Page 1 of 3 Aug 28, 2013 07:39:07PM MDT

    E-Print Network [OSTI]

    http://www.staradvertiser.com/newspremium/20130824_Small_school_stands_tall_as_science_powerhouse_.html?id=220927791&c=n Page 1 of 3 Aug 28, 2013 07:39:07PM MDT Small school stands tall as science powerhouse POSTED roughly 2,000 feet, then transmitted data to Earth as it aero-braked and fell at prescribed speeds before

  2. Infrared colour properties of nearby radio-luminous galaxies

    E-Print Network [OSTI]

    Yang, Xiao-hong; Huang, Yan

    2015-01-01T23:59:59.000Z

    By combining the data of the Two Micron All Sky Survey (2MASS), the Wide Field Infrared Survey Explorer (WISE) and the Akari satellite, we study the infrared colour properties of a sample of 2712 nearby radio-luminous galaxies (RLGs). These RLGs are divided into radio-loud (RL) active galactic nuclei (AGNs), mainly occurring at redshifts of $0.05$ 3.0. We also analyse the MIR colours of RL AGNs divided into low- and high-excitation radio galaxies (LERGs and HERGs, respectively). The ([3.4]-[4.6])$-$([4.6]-[12]) diagram clearly shows separate distributions of LERGs and HERGs and a region of overlap, which suggests that LERGs and HERGs have different MIR properties. LERGs are responsible for the double-core distribution of RL AGNs on the ([3.4]-[4.6])$-$([4.6]-[12]) diagram. In addition, we also suggest 90$-$140$\\mu$m band spectral index $\\alpha(90,140)<-1.4$ as a criterion of selecting nearby active galaxies with non-thermal emissions at FIR wavelengths.

  3. HI emission and absorption in nearby, gas-rich galaxies

    E-Print Network [OSTI]

    Reeves, S N; Allison, J R; Koribalski, B S; Curran, S J; Pracy, M B

    2015-01-01T23:59:59.000Z

    We present the results of a targeted search for intervening HI absorption in six nearby, gas-rich galaxies using the Australia Telescope Compact Array (ATCA). The sightlines searched have impact parameters of 10-20 kpc. By targeting nearby galaxies we are also able to map their HI emission, allowing us to directly relate the absorption-line detection rate to the extended HI distribution. The continuum sightlines intersect the HI disk in four of the six galaxies, but no intervening absorption was detected. Of these four galaxies, we find that three of the non-detections are the result of the background source being too faint. In the fourth case we find that the ratio of the spin temperature to the covering factor ($T_{\\mathrm{S}}/f$) must be much higher than expected ($\\gtrsim$5700 K) in order to explain the non-detection. We discuss how the structure of the background continuum sources may have affected the detection rate of HI absorption in our sample, and the possible implications for future surveys. Future...

  4. Demonstration of the Federation of OMF Control Framework with PlanetLab Peer-to-peer resolution of an obstacle problem using the P2Pdc framework

    E-Print Network [OSTI]

    Ingrand, François

    of an obstacle problem using the P2Pdc framework Scenario: - Distributed Application for Problem Solving

  5. Catalog of Nearby Galaxies and the Local Cosmic Web

    E-Print Network [OSTI]

    Igor D. Karachentsev; Valentina E. Karachentseva; Walter K. Huchtmeier; Dmitry I. Makarov

    2004-10-04T23:59:59.000Z

    We compiled an all-sky catalog of 451 nearby galaxies, each having an individual distance estimate $D \\la 10$ Mpc or the radial velocity $V_{LG} -17.0$, which contribute about 4% to the local luminosity density, and $\\sim(10-16)$% to the local HI mass density. We found that the mean local barion density $\\Omega_b(<8$ Mpc) = 2.3% consists of only a half of the global barion density, $\\Omega_b=(4.7\\pm0.6)$% (Spergel et al. 2003). The mean-square pairwise difference of radial velocities is about 100 km s$^{-1}$ for spatial separations within 1 Mpc, increasing to $\\sim 300$ km s$^{-1}$ on a scale of $\\sim 3$ Mpc.

  6. Separation of suspended particles by arrays of obstacles in microfluidic devices

    E-Print Network [OSTI]

    Zhigang Li; German Drazer

    2006-06-29T23:59:59.000Z

    The stochastic transport of suspended particles through a periodic pattern of obstacles in microfluidic devices is investigated by means of the Fokker-Planck equation. Asymmetric arrays of obstacles have been shown to induce the continuous separation of DNA molecules of different length. The analysis presented here of the asymptotic distribution of particles in a unit cell of these systems shows that separation is only possible in the presence of a driving force with a non-vanishing normal component at the surface of the solid obstacles. In addition, vector separation, in which different species move, in average, in different directions within the device, is driven by differences on the force acting on the various particles and not by differences in the diffusion coefficient. Monte-Carlo simulations performed for different particles and force fields agree with the numerical solutions of the Fokker-Planck equation in the periodic system.

  7. Legal obstacles and incentives to the development of small scale hydroelectric potential in Michigan

    SciTech Connect (OSTI)

    None,

    1980-05-01T23:59:59.000Z

    The legal and institutional obstacles to the development of small-scale hydroelectric energy at the state level is described. The Federal government also exercises extensive regulatory authority in the area. The first obstacle which any developer must confront in Michigan is obtaining the authority to utilize the river bed, banks, and flowing water at a proposed dam site. This involves a determination of ownership of the stream banks and bed, and the manner of obtaining either their title or use; and existing constraints with regard to the use of the water. Michigan follows the riparian theory of water law. The direct regulation; indirect regulation; public utilities regulation; financing; and taxation are discussed.

  8. INFRARED SPECTRAL ENERGY DISTRIBUTIONS OF NEARBY GALAXIES D. A. Dale,1

    E-Print Network [OSTI]

    Joseph, Robert D.

    INFRARED SPECTRAL ENERGY DISTRIBUTIONS OF NEARBY GALAXIES D. A. Dale,1 G. J. Bendo,2 C. W ABSTRACT The Spitzer Infrared Nearby Galaxies Survey (SINGS) is carrying out a comprehensive) are presented using broad- band imaging data from Spitzer, 2MASS, ISO, IRAS, and SCUBA. The infrared colors

  9. MID-INFRARED SPECTRAL DIAGNOSTICS OF NUCLEAR AND EXTRANUCLEAR REGIONS IN NEARBY GALAXIES

    E-Print Network [OSTI]

    Draine, Bruce T.

    MID-INFRARED SPECTRAL DIAGNOSTICS OF NUCLEAR AND EXTRANUCLEAR REGIONS IN NEARBY GALAXIES D. A. Dale,13 and F. Walter5 Received 2006 February 24; accepted 2006 March 31 ABSTRACT Mid-infrared diagnostics are presented for a large portion of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample plus archival

  10. Erosion Damage of Nearby Plasma-Facing Components during a Disruption on the Divertor Plate*

    E-Print Network [OSTI]

    Harilal, S. S.

    Erosion Damage of Nearby Plasma-Facing Components during a Disruption on the Divertor Plate* A those of the United States Governmentor any agency thereof. #12;Erosion Damage of Nearby Plasma radiation emitted by heating of the vapor cloud. This radiation energy can cause serious erosion damage

  11. Kuiper belt structure around nearby super-Earth host stars

    E-Print Network [OSTI]

    Kennedy, Grant M; Marmier, Maxime; Greaves, Jane S; Wyatt, Mark C; Bryden, Geoffrey; Holland, Wayne; Lovis, Christophe; Matthews, Brenda C; Pepe, Francesco; Sibthorpe, Bruce; Udry, Stéphane

    2015-01-01T23:59:59.000Z

    We present new observations of the Kuiper belt analogues around HD 38858 and HD 20794, hosts of super-Earth mass planets within 1 au. As two of the four nearby G-type stars (with HD 69830 and 61 Vir) that form the basis of a possible correlation between low-mass planets and debris disc brightness, these systems are of particular interest. The disc around HD 38858 is well resolved with Herschel and we constrain the disc geometry and radial structure. We also present a probable JCMT sub-mm continuum detection of the disc and a CO J=2-1 upper limit. The disc around HD 20794 is much fainter and appears marginally resolved with Herschel, and is constrained to be less extended than the discs around 61 Vir and HD 38858. We also set limits on the radial location of hot dust recently detected around HD 20794 with near-IR interferometry. We present HARPS upper limits on unseen planets in these four systems, ruling out additional super-Earths within a few au, and Saturn-mass planets within 10 au. We consider the disc st...

  12. The Nuclear Near-Infrared Spectral Properties of Nearby Galaxies

    E-Print Network [OSTI]

    Mason, R E; Martins, L; Riffel, R; Martin, O Gonzalez; Almeida, C Ramos; Dutra, D Ruschel; Ho, L C; Thanjavur, K; Flohic, H; Alonso-Herrero, A; Lira, P; McDermid, R; Riffel, R A; Schiavon, R P; Winge, C; Hoenig, M D; Perlman, E

    2015-01-01T23:59:59.000Z

    We present spectra of the nuclear regions of 50 nearby (D = 1 - 92 Mpc, median = 20 Mpc) galaxies of morphological types E to Sm. The spectra, obtained with the Gemini Near-IR Spectrograph on the Gemini North telescope, cover a wavelength range of approximately 0.85-2.5 microns at R~1300--1800. There is evidence that most of the galaxies host an active galactic nucleus (AGN), but the range of AGN luminosities (log (L2-10 keV [erg/s]) = 37.0-43.2) in the sample means that the spectra display a wide variety of features. Some nuclei, especially the Seyferts, exhibit a rich emission-line spectrum. Other objects, in particular the type 2 Low Ionisation Nuclear Emission Region galaxies, show just a few, weak emission lines, allowing a detailed view of the underlying stellar population. These spectra display numerous absorption features sensitive to the stellar initial mass function, as well as molecular bands arising in cool stars, and many other atomic absorption lines. We compare the spectra of subsets of galaxie...

  13. Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open channel flow

    E-Print Network [OSTI]

    Boyer, Edmond

    Bow-wave-like hydraulic jump and horseshoe vortex around an obstacle in a supercritical open the obstacle, two main flow structures are observed: i a hydraulic jump in the near-surface region and ii turbulent regime , the detachment length of the hydraulic jump exceeds the one of the horseshoe vortex

  14. Yield drag in a two-dimensional foam flow around a circular obstacle: Effect of liquid fraction

    E-Print Network [OSTI]

    Cox, Simon

    Yield drag in a two-dimensional foam flow around a circular obstacle: Effect of liquid fraction of foams around a circular obstacle within a long channel. In experiments, we confine the foam between liquid and glass surfaces. In simulations, we use a deterministic software, the Surface Evolver

  15. Failure-Tolerant Path Planning for the PA-10 Robot Operating Amongst Obstacles

    E-Print Network [OSTI]

    Maciejewski, Anthony A.

    Failure-Tolerant Path Planning for the PA-10 Robot Operating Amongst Obstacles Rodrigo S. Jamisola/or orientation in the workspace despite any single locked-joint failure at any time. An algorithm is presented relative to its task, only a single locked-joint failure occurs at any given time, the robot is capable

  16. Non-Economic Obstacles to Wind Deployment: Issues and Regional Differences (Presentation)

    SciTech Connect (OSTI)

    Baring-Gould, I.

    2014-05-01T23:59:59.000Z

    This presentation provides an overview of national obstacles to wind deployment, with regional assessments. A special mention of offshore projects and distributed wind projects is provided. Detailed maps examine baseline capacity, military and flight radar, golden and bald eagle habitat, bat habitat, whooping crane habitat, and public lands. Regional deployment challenges are also discussed.

  17. Obstacles to Global CO2 Trading: A Familiar Problem A. Denny Ellerman1

    E-Print Network [OSTI]

    obstacles to the development of an international CO2 emissions trading system, but the biggest is a feature emissions trading. The paper reviews the various instruments by which such the Kyoto target might be met. The development of an international system for CO2 emissions trading should not be expected to be either quick

  18. Title of dissertation: A CONTINUUM MODEL FOR FLOCKING: OBSTACLE AVOIDANCE, EQUILIBRIUM,

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of dissertation: A CONTINUUM MODEL FOR FLOCKING: OBSTACLE AVOIDANCE, EQUILIBRIUM, AND STABILITY Nicholas Alexander Mecholsky, Doctor of Philosophy, 2010 Dissertation directed by: Professor of animal groups is a subject of growing attention. In this dissertation, we present a partial- differential

  19. A Probabilistic-Numerical Approximation for an Obstacle Problem Arising in Game Theory

    SciTech Connect (OSTI)

    Gruen, Christine, E-mail: christine.gruen@univ-brest.fr [Laboratoire de Mathematiques de Brest UMR 6205 (France)

    2012-12-15T23:59:59.000Z

    We investigate a two-player zero-sum stochastic differential game in which one of the players has more information on the game than his opponent. We show how to construct numerical schemes for the value function of this game, which is given by the solution of a quasilinear partial differential equation with obstacle.

  20. Invited Presentation, EdMedia '94 Vancouver, Canada page 1 Issues and Obstacles with Multimedia Authoring

    E-Print Network [OSTI]

    Invited Presentation, EdMedia '94 Vancouver, Canada page 1 Issues and Obstacles with Multimedia, multimedia authoring involves making hard choices, forecasting technological evolution and adapting of the common threads shared by three dissimilar cases of multimedia authoring which we have experimented with

  1. Turbidity current flow over an obstacle and phases of sediment wave generation

    E-Print Network [OSTI]

    Strauss, Moshe

    2011-01-01T23:59:59.000Z

    We study the flow of particle-laden turbidity currents down a slope and over an obstacle. A high-resolution 2D computer simulation model is used, based on the Navier-Stokes equations. It includes poly-disperse particle grain sizes in the current and substrate. Particular attention is paid to the erosion and deposition of the substrate particles, including application of an active layer model. Multiple flows are modeled from a lock release that can show the development of sediment waves (SW). These are stream-wise waves that are triggered by the increasing slope on the downstream side of the obstacle. The initial obstacle is completely erased by the resuspension after a few flows leading to self consistent and self generated SW that are weakly dependant on the initial obstacle. The growth of these waves is directly related to the turbidity current being self sustaining, that is, the net erosion is more than the net deposition. Four system parameters are found to influence the SW growth: (1) slope, (2) current ...

  2. The effects of obstacle geometry on jet mixing in releases of silane 

    E-Print Network [OSTI]

    Sposato, Christina F

    2000-01-01T23:59:59.000Z

    Releases of silane into air and the effects of obstacles were modeled with the Computational Fluid Dynamics (CFD) code, FLUENT. First the CFD code simulated the release of a free turbulent jet of silane into air to assure that the code agreed...

  3. A Moving Object Tracked by A Mobile Robot with Real-Time Obstacles Avoidance Capacity

    E-Print Network [OSTI]

    Abidi, Mongi A.

    . The robotic platform uses a visual camera to sense the movement of the desired object and a range sensor that assist a human driver for safety or comfort [6, 8]. NASA has applied this to help astronauts to carryA Moving Object Tracked by A Mobile Robot with Real-Time Obstacles Avoidance Capacity Chung

  4. Black holes at the centers of nearby dwarf galaxies

    SciTech Connect (OSTI)

    Moran, Edward C.; Shahinyan, Karlen; Sugarman, Hannah R.; Vélez, Darik O. [Astronomy Department, Wesleyan University, Middletown, CT 06459 (United States); Eracleous, Michael [Department of Astronomy and Astrophysics, and Institute for Gravitation and the Cosmos, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)

    2014-12-01T23:59:59.000Z

    Using a distance-limited portion of the Sloan Digital Sky Survey (SDSS) Data Release 7, we have identified 28 active galactic nuclei (AGNs) in nearby (d?80 Mpc) low-mass, low-luminosity dwarf galaxies. The accreting objects at the galaxy centers are expected to be intermediate-mass black holes (IMBHs) with M{sub BH}?10{sup 6} M{sub ?}. The AGNs were selected using several optical emission-line diagnostics after careful modeling of the continuum present in the spectra. We have limited our survey to objects with spectral characteristics similar to those of Seyfert nuclei, excluding emission-line galaxies with ambiguous spectra that could be powered by stellar processes. Thus, as a set, the host galaxies in our sample are the least massive objects in the very local universe certain to contain central black holes. Our sample is dominated by narrow-line (type 2) AGNs, and it appears to have a much lower fraction of broad-line objects than that observed for luminous, optically selected Seyfert galaxies. Given our focus on the nearest objects included in the SDSS, our survey is more sensitive to low-luminosity emission than previous optical searches for AGNs in low-mass galaxies. The [O iii] ?5007 luminosities of the Seyfert nuclei in our sample have a median value of L{sub 5007}=2×10{sup 5} L{sub ?} and extend down to ?10{sup 4} L{sub ?}. Using published data for broad-line IMBH candidates, we have derived an [O iii] bolometric correction of log(L{sub bol}/L{sub 5007})=3.0±0.3, which is significantly lower than values obtained for high-luminosity AGNs. Applying this correction to our sample, we obtain minimum black hole mass estimates that fall mainly in the 10{sup 3} M{sub ?}–10{sup 4} M{sub ?} range, which is roughly where the predicted mass functions for different black hole seed formation scenarios overlap the most. In the stellar mass range that includes the bulk of the AGN host galaxies in our sample, we derive a lower limit on the AGN fraction of a few percent, indicating that active nuclei in dwarf galaxies are not as rare as previously thought.

  5. The Masses of Nearby Dwarfs can be Determined with Gravitational Microlensing

    E-Print Network [OSTI]

    B. Paczynski

    1995-04-27T23:59:59.000Z

    Microlensing of distant stars in the Milky Way by the nearby high proper motion stars offers a direct way to precisely measure the masses of single lower main sequence stars and brown dwarfs.

  6. Wave blocking and partial transmission in subcritical flows over an obstacle

    E-Print Network [OSTI]

    Léo-Paul Euvé; Florent Michel; Renaud Parentani; Germain Rousseaux

    2015-02-06T23:59:59.000Z

    We study and measure the transmission coefficient of counter-propagating shallow-water waves produced by a wave generator and scattered by an obstacle. To precisely compare theoretical predictions and experimental data, we consider $\\sim 25$ frequencies for 5 subcritical background flows, where the maximum value of the Froude number ranges from $0.5$ to $0.75$. For each flow, the transmission coefficient displays a sharp transition separating total transmission from wave-blocking. Both the width and the central frequency of the transition are in good agreement with their theoretical values. The shape of the obstacle is identical to that used by the Vancouver team in the recent experiment aiming at detecting the analogue of stimulated Hawking radiation. Our results are compatible with the observations that have been reported. They complete them by establishing that the contribution of the transmission coefficient cannot be neglected for the lower half of the probed frequency range.

  7. Legal obstacles and incentives to the development of small scale hydroelectric potential in Wisconsin

    SciTech Connect (OSTI)

    None,

    1980-05-01T23:59:59.000Z

    The legal and institutional obstacles to the development of small-scale hydroelectric energy at the state level are discussed. The Federal government also exercises extensive regulatory in the area, and the dual regulatory system from the standpoint of the appropriate legal doctrine, the law of pre-emption, application of the law to the case of hydroelectric development, and an inquiry into the practical use of the doctrine by the FERC is examined. The initial obstacle that all developers confront in Wisconsin is obtaining the authority to utilize the bed, banks, and flowing water at a proposed dam site. This involves a determination of ownership of the stream banks and bed and the manner of obtaining either their title or use; and existing constraints with regard to the use of the water. Wisconsin follows the riparian theory of water law.

  8. Some Obstacles to United States Direct Private Foreign Investment in Manufacturing: 1950-1958.

    E-Print Network [OSTI]

    Stewart, Milton Dudley

    1960-01-01T23:59:59.000Z

    their productivity and thus increase their costs. In order to avoid interruptions in power service, many firms have established their own power generating units. Needless to say, this may sometimes be quite costly and represents an additional investment on which...SOME OBSTACLES TO UNITED STATES DIRECT PRIVATE POREIGN INVESTMENT IN MANUPACTURING: 1950-195S A Thesis By Milton Dudley Stewart, Jr. Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment...

  9. Lower bounds on the obstacle number of graphs Padmini Mukkamala1, Janos Pach2, and Domotor Palvolgyi3

    E-Print Network [OSTI]

    Pach, János

    Lower bounds on the obstacle number of graphs Padmini Mukkamala1, J´anos Pach2, and D¨om¨ot¨or P are extensively studied and used in computational geometry, robot motion planning, computer vision, sensor

  10. HIGH-VELOCITY CLOUDS IN THE NEARBY SPIRAL GALAXY M 83

    E-Print Network [OSTI]

    Miller, Eric D.

    We present deep H I 21 cm and optical observations of the face-on spiral galaxy M 83 obtained as part of a project to search for high-velocity clouds (HVCs) in nearby galaxies. Anomalous-velocity neutral gas is detected ...

  11. Yield drag in a two-dimensional foam flow around a circular obstacle: Effect of liquid fraction

    E-Print Network [OSTI]

    Christophe Raufaste; B. Dollet; Simon Cox; Yi Jiang; François Graner

    2007-07-09T23:59:59.000Z

    We study the two-dimensional flow of foams around a circular obstacle within a long channel. In experiments, we confine the foam between liquid and glass surfaces. In simulations, we use a deterministic software, the Surface Evolver, for bubble details and a stochastic one, the extended Potts model, for statistics. We adopt a coherent definition of liquid fraction for all studied systems. We vary it in both experiments and simulations, and determine the yield drag of the foam, that is, the force exerted on the obstacle by the foam flowing at very low velocity. We find that the yield drag is linear over a large range of the ratio of obstacle to bubble size, and is independent of the channel width over a large range. Decreasing the liquid fraction, however, strongly increases the yield drag; we discuss and interpret this dependence.

  12. UCAC4 nearby star survey: A search for our stellar neighbors

    SciTech Connect (OSTI)

    Finch, Charlie T.; Zacharias, Norbert [U.S. Naval Observatory, Washington, DC 20392–5420 (United States); Subasavage, John P. [U.S. Naval Observatory, Flagstaff, AZ 86005–8521 (United States); Henry, Todd J. [RECONS Institute, Chambersburg, PA 17201 (United States); Riedel, Adric R., E-mail: finch@usno.navy.mil [Hunter College, New York, NY 10065 (United States)

    2014-12-01T23:59:59.000Z

    We use data from the U.S. Naval Observatory fourth CCD Astrograph Catalog (UCAC4) in combination with photometry from the AAVSO Photometric All-Sky Survey and Two Micron All-Sky Survey to identify stars within 25 pc of the Sun. A sample of nearby stars with accurate trigonometric parallaxes from the Research Consortium On Nearby Stars is used to generate a set of 16 new photometric color–M{sub K{sub s}} relations that provide distance estimates with uncertainties of 15%. This work expands the available suites of well-calibrated photometric distance relations that can be used to identify nearby stellar systems. The distance relations are used with quality cuts to extract an initial sample of stars from the UCAC4 estimated to be within 25 pc. Color, proper motion, and existing literature sources are then used to obtain a clean sample of red dwarfs, while limiting the amount of contamination from background giants, resulting in a sample of 1761 candidate nearby stars within 25 pc. Of these, 339 are new discoveries with no previously known published parallax or distance estimate, primarily with proper motions less than 0.2 arcsec yr{sup ?1}. Five stars are estimated to be within 10 pc, with the nearest, TYC 3980 1081 1, with V=10.50 estimated to be at 5.9 pc. That several hundred new stars have been revealed so close to the Sun illustrates once again that there is considerable work yet to be done to map the solar neighborhood and that additional nearby stars are likely still to be discovered.

  13. CAIRNS: The Cluster And Infall Region Nearby Survey II. Environmental Dependence of Infrared Mass-to-Light Ratios

    E-Print Network [OSTI]

    K. Rines; M. J. Geller; A. Diaferio; M. J. Kurtz; T. H. Jarrett

    2004-06-11T23:59:59.000Z

    CAIRNS (Cluster And Infall Region Nearby Survey) is a spectroscopic survey of the infall regions surrounding nine nearby rich clusters of galaxies. In Paper I, we used redshifts within $\\sim 10\\Mpc$ of the centers of the clusters to determine the mass profiles of the clusters based on the phase space distribution of the galaxies. Here, we use 2MASS photometry and an additional \

  14. Over-parameterisation,a major obstacle to the use of artificial neural networks in hydrology ? Hydrology and Earth System Sciences, 7(5), 693706 (2003) EGU

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    2003-01-01T23:59:59.000Z

    Over-parameterisation,a major obstacle to the use of artificial neural networks in hydrology ? 693 Hydrology and Earth System Sciences, 7(5), 693706 (2003) © EGU Over-parameterisation, a major obstacle to the use of artificial neural networks in hydrology ? Eric Gaume and Raphael Gosset Ecole Nationale des

  15. Obstacles and Call to Action as a result of the Sept. 22nd and 23rd Biofuels Sustainability portion of the conference.

    E-Print Network [OSTI]

    Kyte, Michael

    Group 1 Obstacles and Call to Action as a result of the Sept. 22nd and 23rd Biofuels Sustainability. 22nd and 23rd Biofuels Sustainability portion of the confer- ence. #12;Group 3 Obstacles and Call to Action as a result of the Sept. 22nd and 23rd Biofuels Sustainability portion of the conference

  16. hal-00090531,version4-6Jul2007 Yield drag in a two-dimensional foam flow around a circular obstacle

    E-Print Network [OSTI]

    Boyer, Edmond

    hal-00090531,version4-6Jul2007 Yield drag in a two-dimensional foam flow around a circular obstacle-dimensional flow of foams around a circular obstacle within a long channel. In experiments, we confine the foam between liquid and glass surfaces. In simulations, we use a deterministic software, the Surface Evolver

  17. Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions

    E-Print Network [OSTI]

    Strained-Si-on-Insulator (SSOI) and SiGe-on-Insulator (SGOI): Fabrication Obstacles and Solutions-Si and SiGe-on-insulator were fabricated, combining both the benefits of high-mobility strained-Si and SOI) to oxidized handle wafers. Layer transfer onto insulating handle wafers can be accomplished using grind

  18. Evaluation of Direct and Indirect Haptic Aiding in an Obstacle Avoidance Task for Tele-Operated Systems

    E-Print Network [OSTI]

    and Automation, University of Pisa, Pisa, 56126, Italy (e-mail: lpollini@dsea.unipi.it) *** Dept. of Brain in teleoperation environments in which the operator is physically separated from the vehicle. It appears reasonable Vehicles), Human-machine interface, Telepresence, Obstacle avoidance, Multi-sensory interface. 1

  19. Development of an Integrated Sensor System for Obstacle Detection and Terrain Evaluation for Application to Unmanned Ground

    E-Print Network [OSTI]

    Florida, University of

    Development of an Integrated Sensor System for Obstacle Detection and Terrain Evaluation field of view of 50 degrees and 38 degrees, respectively. Two sensor systems were utilized to evaluate., Wexford Pennsylvania ABSTRACT This paper describes the development and performance of a sensor system

  20. The Russian oil industry between public and private governance: obstacles to international oil companies' investment strategies1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The Russian oil industry between public and private governance: obstacles to international oil, July 2004 Submitted to Energy Policy The low level of involvement by international oil companies by international oil companies in that country. Meanwhile, Russia has become a principal actor on the international

  1. Constraints on decaying dark matter from Fermi observations of nearby galaxies and clusters

    SciTech Connect (OSTI)

    Dugger, Leanna; Profumo, Stefano [Department of Astronomy and Department of Physics, University of California Berkeley, 601 Campbell Hall, Berkeley, CA (United States); Jeltema, Tesla E., E-mail: greentee01@gmail.com, E-mail: tesla@ucolick.org, E-mail: profumo@scipp.ucsc.edu [UCO/Lick Observatories, 1156 High St., Santa Cruz, CA 95064 (United States)

    2010-12-01T23:59:59.000Z

    We analyze the impact of Fermi gamma-ray observations (primarily non-detections) of selected nearby galaxies, including dwarf spheroidals, and of clusters of galaxies on decaying dark matter models. We show that the fact that galaxy clusters do not shine in gamma rays puts the most stringent limits available to-date on the lifetime of dark matter particles for a wide range of particle masses and decay final states. In particular, our results put strong constraints on the possibility of ascribing to decaying dark matter both the increasing positron fraction reported by PAMELA and the high-energy feature in the electron-positron spectrum measured by Fermi. Observations of nearby dwarf galaxies and of the Andromeda Galaxy (M31) do not provide as strong limits as those from galaxy clusters, while still improving on previous constraints in some cases.

  2. Radio emission of nearby clusters of galaxies at 102. 5 MHz

    SciTech Connect (OSTI)

    Gubanov, A.G.; Dagkesamanskii, R.D.; Rudenko, V.A.

    1980-09-01T23:59:59.000Z

    Observations of 24 nearby Abell galaxy clusters with the Lebedev aperture-synthesis antenna array at 102.5 MHz indicate that the radio luminosity of a cluster increases with its richness class R. For clusters with R> or =1 the luminosity function conforms to a power law with exponent -0.85 in the range 3 x 10/sup 24/< or =L< or =3 x 10/sup 26/ W/Hz.

  3. Identification of four RXTE Slew Survey sources with nearby luminous active galactic nuclei

    E-Print Network [OSTI]

    M. Revnivtsev; S. Sazonov; E. Churazov; S. Trudolyubov

    2005-11-17T23:59:59.000Z

    Based on RXTE scans and observations with the SWIFT/XRT telescope and INTEGRAL observatory, we report the identification of four X-ray sources discovered during the RXTE Slew Survey of the |b|>10deg sky with nearby (z ~ 0.017-0.098) luminous (log L_2-10keV ~ 42.7-44 erg/s) active galactic nuclei. Two of the objects exhibit heavily intrinsically absorbed X-ray spectra (NHL~10^23 cm^-2).

  4. Oxygen Abundances in Nearby Stars. Clues to the formation and evolution of the Galactic disk

    E-Print Network [OSTI]

    I. Ramirez; C. Allende Prieto; D. L. Lambert

    2007-01-12T23:59:59.000Z

    The abundances of iron and oxygen are homogeneously determined in a sample of 523 nearby (d-0.3, we find no obvious indication of a sudden decrease (i.e., a 'knee') in the [O/Fe] vs. [Fe/H] pattern of thick-disk stars that would connect the thick and thin disk trends at a high metallicity. We conclude that Type Ia supernovae (SN Ia) did not contribute significantly to the chemical enrichment of the thick disk. [Abridged

  5. NEARBY PLANETARY SYSTEMS AS LENSES DURING PREDICTED CLOSE PASSAGES TO BACKGROUND STARS

    SciTech Connect (OSTI)

    Di Stefano, Rosanne; Matthews, James [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Lepine, Sebastien [Department of Astrophysics, Division of Physical Sciences, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States)

    2013-07-10T23:59:59.000Z

    The Einstein rings and proper motions of nearby stars tend to be large. Thus, every year some foreground stars within a few hundred parsecs of Earth induce gravitational lensing events in background stars. In some of these cases, the events may exhibit evidence of planets orbiting the nearby star. In fact, planets can even be discovered during relatively distant passages. Here, we study the lensing signatures associated with planets orbiting nearby high-proper-motion stars. We find the following. (1) Wide-orbit planets can be detected for all distances of closest approach between the foreground and background stars, potentially producing independent events long before and/or after the closest approach. (2) Close-orbit planets can be detected for intermediate distances of closest approach, producing quasiperiodic signatures that may occur days or weeks before and after the stellar-lens event. (3) Planets in the so-called zone for resonant lensing can significantly increase the magnification when the distance of closest approach is small, making the stellar-lens event easier to detect, while simultaneously providing evidence for planets. Because approaches close enough to allow planets to be detected can be predicted, we can plan observing strategies to take advantage of the theoretical framework built in this paper, which describes the sequence of expected effects in terms of a sequence of detection regimes.

  6. The Influence of Galactic Outflows on the Formation of Nearby Dwarf Galaxies

    E-Print Network [OSTI]

    Evan Scannapieco; Andrea Ferrara; Tom Broadhurst

    2000-04-20T23:59:59.000Z

    We show that the gas in growing density perturbations is vulnerable to the influence of winds outflowing from nearby collapsed galaxies that have already formed stars. This suggests that the formation of nearby galaxies with masses less than 10^9 solar masses is likely to be suppressed, irrespective of the details of galaxy formation. An impinging wind may shock heat the gas of a nearby perturbation to above the virial temperature, thereby mechanically evaporating the gas, or the baryons may be stripped from the perturbation entirely if they are accelerated to above the escape velocity. We show that baryonic stripping is the most effective of these two processes, because shock-heated clouds that are too large to be stripped are able to radiatively cool within a sound-crossing time, limiting evaporation. The intergalactic medium temperatures and star-formation rates required for outflows to have a significant influence on the formation of low-mass galaxies are consistent with current observations, but may soon be examined directly via associated distortions in the cosmic microwave background, and with near-infrared observations from the Next Generation Space Telescope, which may detect the supernovae from early-forming stars.

  7. The Oxygen Abundance of Nearby Galaxies from Sloan Digital Sky Survey Spectra

    E-Print Network [OSTI]

    L. S. Pilyugin; T. X. Thuan

    2007-07-19T23:59:59.000Z

    We have derived the oxygen abundance for a sample of nearby galaxies in the Data Release 5 of the Sloan Digital Sky Survey (SDSS) which possess at least two independent spectra of one or several HII regions with a detected [OIII]4363 auroral line. Since, for nearby galaxies, the [OII]3727 nebular line is out of the observed wavelength range, we propose a method to derive (O/H)_ff abundances using the classic Te method coupled with the ff relation. (O/H)_7325 abundances have also been determined, based on the [OII]7320,7330 line intensities, and using a small modification of the standard Te method. The (O/H)_ff and (O/H)_7325 abundances have been derived with both the one- and two-dimensional t_2 - t_3 relations. It was found that the (O/H)_ff abundances derived with the parametric two-dimensional t_2 - t_3 relation are most reliable. Oxygen abundances have been determined in 29 nearby galaxies, based on 84 individual abundance determinations in HII regions. Because of our selection methods, the metallicity of our galaxies lies in the narrow range 8.2 oxygen abundances in the disk of the spiral galaxy NGC 4490 is determined for the first time.

  8. Nearby Outdoor Environmental Support of Older Adults' Yard Activities, Neighborhood Walking and Independent Living in the Community

    E-Print Network [OSTI]

    Wang, Zhe

    2011-02-22T23:59:59.000Z

    to remain healthy and gives them the ability to access daily-life services, and thus extend their independent years at home. Nearby outdoor environments on residential sites and in the neighborhoods may influence older adults' independent living through...

  9. Legal obstacles and incentives to the development of small scale hydroelectric power in Maryland

    SciTech Connect (OSTI)

    None,

    1980-05-01T23:59:59.000Z

    The legal and institutional obstacles to the development of small-scale hydroelectric energy at the state level in Maryland are described. The Federal government also exercises extensive regulatory authority in the area. The dual regulatory system is examined with the aim of creating a more orderly understanding of the vagaries of the system, focusing on the appropriate legal doctrine, the law of pre-emption, application of the law to the case of hydroelectric development, and an inquiry into the practical use of the doctrine by the FERC. In Maryland, by common law rule, title to all navigable waters and to the soil below the high-water mark of those waters is vested in the state as successor to the Lord Proprietary who had received it by grant from the Crown. Rights to non-navigable water, public trust doctrine, and eminent domain are also discussed. Direct and indirect regulations, continuing obligations, loan programs, and regional organizations are described in additional sections.

  10. Hubble Residuals of Nearby SN Ia Are Correlated with Host Galaxy Masses

    SciTech Connect (OSTI)

    Kelly, Patrick L.; /KIPAC, Menlo Park /SLAC; Hicken, Malcolm; /Harvard-Smithsonian Ctr. Astrophys.; Burke, David L.; /KIPAC, Menlo Park /SLAC; Mandel, Kaisey S.; Kirshner, Robert P.; /Harvard-Smithsonian Ctr. Astrophys.

    2010-05-03T23:59:59.000Z

    From Sloan Digital Sky Survey u{prime} g{prime} r{prime} i{prime} z{prime} imaging, we estimate the stellar masses of the host galaxies of 70 low redshift SN Ia (0.015 < z < 0.08) from the hosts absolute luminosities and mass-to-light ratios. These nearby SN were discovered largely by searches targeting luminous galaxies, and we find that their host galaxies are substantially more massive than the hosts of SN discovered by the flux-limited Supernova Legacy Survey. Testing four separate light curve fitters, we detect {approx}2.5{sigma} correlations of Hubble residuals with both host galaxy size and stellar mass, such that SN Ia occurring in physically larger, more massive hosts are {approx}10% brighter after light curve correction. The Hubble residual is the deviation of the inferred distance modulus to the SN, calculated from its apparent luminosity and light curve properties, away from the expected value at the SN redshift. Marginalizing over linear trends in Hubble residuals with light curve parameters shows that the correlations cannot be attributed to a light curve-dependent calibration error. Combining 180 higher-redshift ESSENCE, SNLS, and HigherZ SN with 30 nearby SN whose host masses are less than 10{sup 10.8} M{circle_dot} n a cosmology fit yields 1 + w = 0.22{sub -0.108}{sup +0.152}, while a combination where the 30 nearby SN instead have host masses greater than 10{sup 10.8} M{circle_dot} yields 1 + w = ?0.03{sub -0.143}{sup +0.217}. Progenitor metallicity, stellar population age, and dust extinction correlate with galaxy mass and may be responsible for these systematic effects. Host galaxy measurements will yield improved distances to SN Ia.

  11. Timing the Nearby Isolated Neutron Star RX J1856.5-3754

    E-Print Network [OSTI]

    Van Kerkwijk, M H

    2007-01-01T23:59:59.000Z

    RX J1856.5-3754 is the X-ray brightest among the nearby isolated neutron stars. Its X-ray spectrum is thermal, and is reproduced remarkably well by a black-body, but its interpretation has remained puzzling. One reason is that the source did not exhibit pulsations, and hence a magnetic field strength--vital input to atmosphere models--could not be estimated. Recently, however, very weak pulsations were discovered. Here, we analyze these in detail, using all available data from the XMM-Newton and Chandra X-ray observatories. From frequency measurements, we set a 2-sigma upper limit to the frequency derivative of \\dot\

  12. Discovery of a large dust disk around the nearby star AU Microscopium

    E-Print Network [OSTI]

    Paul Kalas; Michael C. Liu; Brenda C. Matthews

    2004-03-05T23:59:59.000Z

    We present the discovery of a circumstellar dust disk surrounding AU Microscopium (AU Mic, GJ 803, HD 197481). This young M star at 10 parsec has the same age and origin as beta Pictoris, another nearby star surrounded by a dust disk. The AU Mic disk is detected between 50 AU and 210 AU radius, a region where dust lifetimes exceed the present stellar age. Thus, AU Mic is the nearest star where we directly observe the solid material required for planet formation. Since 85% of stars are M-type, the AU Mic disk provides new clues on how the majority of planetary systems might form and evolve.

  13. The Practical Obstacles of Data Transfer: Why researchers still love scp

    SciTech Connect (OSTI)

    Nam, Hai Ah [ORNL; Hill, Jason J [ORNL; Parete-Koon, Suzanne T [ORNL

    2014-01-01T23:59:59.000Z

    The importance of computing facilities is heralded every six months with the announcement of the new Top500 list, showcasing the world s fastest supercomputers. Unfortu- nately, with great computing capability does not come great long-term data storage capacity, which often means users must move their data to their local site archive, to remote sites where they may be doing future computation or anal- ysis, or back to their home institution, else face the dreaded data purge that most HPC centers employ to keep utiliza- tion of large parallel filesystems low to manage performance and capacity. At HPC centers, data transfer is crucial to the scientific workflow and will increase in importance as computing systems grow in size. The Energy Sciences Net- work (ESnet) recently launched its fifth generation network, a 100 Gbps high-performance, unclassified national network connecting more than 40 DOE research sites to support scientific research and collaboration. Despite the tenfold increase in bandwidth to DOE research sites amenable to multiple data transfer streams and high throughput, in prac- tice, researchers often under-utilize the network and resort to painfully-slow single stream transfer methods such as scp to avoid the complexity of using multiple stream tools such as GridFTP and bbcp, and contend with frustration from the lack of consistency of available tools between sites. In this study we survey and assess the data transfer methods pro- vided at several DOE supported computing facilities, includ- ing both leadership-computing facilities, connected through ESnet. We present observed transfer rates, suggested opti- mizations, and discuss the obstacles the tools must overcome to receive wide-spread adoption over scp.

  14. HI observations of nearby galaxies I. The first list of the Karachentsev catalog

    E-Print Network [OSTI]

    W. K. Huchtmeier; I. D. Karachentsev; V. E. Karachentseva; M. Ehle

    1999-11-18T23:59:59.000Z

    We present HI observations of the galaxies in the first list of the Karachentsev catalog of previously unknown nearby dwarf galaxies (Karachentseva & Karachentsev 1998). This survey covers all known nearby galaxy groups within the Local Volume (i.e. within 10 Mpc) and their environment, that is about 25% of the total sky. A total of 257 galaxies have been observed with a detection rate of 60%. We searched a frequency band corresponding to heliocentric radial velocities from -470 km/s to about +4000 km/s. Non-detections are either due to limited coverage in radial velocity, confusion with Local HI (mainly in the velocity range -140 km/s to +20 km/s, or lack of sensitivity for very weak emission. 25% of the detected galaxies are located within the Local Volume. Those galaxies are dwarf galaxies judged by their optical linear diameter (1.4 +/- 0.2 kpc on the average), their mean total HI mass (4.6 E7 solar masses), and their observed linewidths (39 km/s).

  15. HERSCHEL FAR-INFRARED AND SUBMILLIMETER PHOTOMETRY FOR THE KINGFISH SAMPLE OF NEARBY GALAXIES

    SciTech Connect (OSTI)

    Dale, D. A. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Aniano, G.; Draine, B. T. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Engelbracht, C. W.; Hinz, J. L.; Montiel, E. J. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Krause, O.; Groves, B. A. [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany); Roussel, H. [Institut d'Astrophysique de Paris, UMR7095 CNRS, Universite Pierre and Marie Curie, 98 bis Boulevard Arago, 75014 Paris (France); Appleton, P. N. [NASA Herschel Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Armus, L.; Beirao, P. [Spitzer Science Center, California Institute of Technology, MC 314-6, Pasadena, CA 91125 (United States); Bolatto, A. D. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Brandl, B. R. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Calzetti, D.; Crocker, A. F. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Croxall, K. V. [Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States); Galametz, M. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Gordon, K. D. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Hao, C.-N., E-mail: ddale@uwyo.edu [Tianjin Astrophysics Center, Tianjin Normal University, Tianjin 300387 (China); and others

    2012-01-20T23:59:59.000Z

    New far-infrared and submillimeter photometry from the Herschel Space Observatory is presented for 61 nearby galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel (KINGFISH) sample. The spatially integrated fluxes are largely consistent with expectations based on Spitzer far-infrared photometry and extrapolations to longer wavelengths using popular dust emission models. Dwarf irregular galaxies are notable exceptions, as already noted by other authors, as their 500 {mu}m emission shows evidence for a submillimeter excess. In addition, the fraction of dust heating attributed to intense radiation fields associated with photodissociation regions is found to be (21 {+-} 4)% larger when Herschel data are included in the analysis. Dust masses obtained from the dust emission models of Draine and Li are found to be on average nearly a factor of two higher than those based on single-temperature modified blackbodies, as single blackbody curves do not capture the full range of dust temperatures inherent to any galaxy. The discrepancy is largest for galaxies exhibiting the coolest far-infrared colors.

  16. CAIRNS: The Cluster And Infall Region Nearby Survey I. Redshifts and Mass Profiles

    E-Print Network [OSTI]

    K. Rines; M. J. Geller; M. J. Kurtz; A. Diaferio

    2003-06-25T23:59:59.000Z

    The CAIRNS (Cluster And Infall Region Nearby Survey) project is a spectroscopic survey of the infall regions surrounding eight nearby, rich, X-ray luminous clusters of galaxies. We collect 15665 redshifts (3471 new or remeasured) within \\sim 5-10 Mpc of the centers of the clusters, making it the largest study of the infall regions of clusters. We determine cluster membership and the mass profiles of the clusters based on the phase space distribution of the galaxies. All of the clusters display decreasing velocity dispersion profiles. The mass profiles are fit well by functional forms based on numerical simulations but exclude an isothermal sphere. Specifically, NFW and Hernquist models provide good descriptions of cluster mass profiles to their turnaround radii. Our sample shows that the predicted infall pattern is ubiquitous in rich, X-ray luminous clusters over a large mass range. The caustic mass estimates are in excellent agreement with independent X-ray estimates at small radii and with virial estimates at intermediate radii. The mean ratio of the caustic mass to the X-ray mass is 1.03\\pm0.11 and the mean ratio of the caustic mass to the virial mass (when corrected for the surface pressure term) is 0.93\\pm0.07. We further demonstrate that the caustic technique provides reasonable mass estimates even in merging clusters.

  17. The resolved star-formation relation in nearby active galactic nuclei

    E-Print Network [OSTI]

    Casasola, Viviana; Combes, Francoise; Garcia-Burillo, Santiago

    2015-01-01T23:59:59.000Z

    We present an analysis of the relation between star formation rate (SFR) surface density (sigmasfr) and mass surface density of molecular gas (sigmahtwo), commonly referred to as the Kennicutt-Schmidt (K-S) relation, at its intrinsic spatial scale, i.e. the size of giant molecular clouds (10-150 pc), in the central, high-density regions of four nearby low-luminosity active galactic nuclei (AGN). We used interferometric IRAM CO(1-0) and CO(2-1), and SMA CO(3-2) emission line maps to derive sigmahtwo and HST-Halpha images to estimate sigmasfr. Each galaxy is characterized by a distinct molecular SF relation at spatial scales between 20 to 200 pc. The K-S relations can be sub-linear, but also super-linear, with slopes ranging from 0.5 to 1.3. Depletion times range from 1 and 2Gyr, compatible with results for nearby normal galaxies. These findings are valid independently of which transition, CO(1-0), CO(2-1), or CO(3-2), is used to derive sigmahtwo. Because of star-formation feedback, life-time of clouds, turbule...

  18. On The Linearity of The Black Hole - Bulge Mass Relation in Active and in Nearby Galaxies

    E-Print Network [OSTI]

    Ari Laor

    2001-01-23T23:59:59.000Z

    Analysis of PG quasar observations suggests a nonlinear relation between the black hole mass, M_BH, and the bulge mass, M_bulge, although a linear relation, as proposed for nearby galaxies, cannot be ruled out. New M_BH values for nearby galaxies from Gebhardt et al., and L_bulge measurements for Seyfert 1 galaxies from Virani et al., are used here to obtain a more accurate value for the slope of the M_BH-M_bulge relation. The combined sample of 40 active and non-active galaxies suggests a significantly nonlinear relation, M_BH\\propto M_bulge^{1.53\\pm 0.14}. Further support for a nonlinear relation is provided by the slope of the M_BH-stellar velocity dispersion relation found recently, and by the low M_BH found in late type spiral galaxies. The mean M_BH/M_bulge ratio is therefore not a universal constant, but rather drops from ~0.5% in bright (M_V ~ -22) ellipticals, to ~0.05% in low luminosity (M_V ~ -18) bulges. Hubble Space Telescope determinations of M_BH in late type spirals, and of the bulge magnitude in narrow line Seyfert 1 galaxies (both predicted to have low M_BH), can further test the validity of the nonlinear M_BH-M_bulge relation.

  19. A Comparison of Independent Star Formation Diagnostics for a UV-Selected Sample of Nearby Galaxies

    E-Print Network [OSTI]

    Sullivan, M; Chan, B; Cram, L; Ellis, R; Treyer, M A; Hopkins, A; Sullivan, Mark; Mobasher, Bahram; Chan, Ben; Cram, Lawrence; Ellis, Richard; Treyer, Marie; Hopkins, Andrew

    2001-01-01T23:59:59.000Z

    We present results from a decimetric radio survey undertaken with the Very Large Array as part of a longer term goal to inter-compare star formation and dust extinction diagnostics, on a galaxy by galaxy basis, for a representative sample of nearby galaxies. For our survey field, Selected Area 57, star formation rates derived from 1.4GHz luminosities are compared with earlier nebular emission line and ultraviolet (UV) continuum diagnostics. We find broad correlations, over several decades in luminosity, between H-alpha, the UV continuum and 1.4GHz diagnostics. However, the scatter in these relations is found to be larger than observational errors, with offsets between the observed relations and those expected assuming constant star-formation histories and luminosity-independent extinction models. We investigate the physical origin of the observed relations, and conclude the discrepancies between different star-formation diagnostics can only be partly explained by simple models of dust extinction in galaxies. ...

  20. Very-High Energy Gamma-Ray Flux Limits for Nearby Active Galactic Nuclei

    E-Print Network [OSTI]

    T. Herr; W. Hofmann; for the H. E. S. S. Collaboration

    2008-11-18T23:59:59.000Z

    Combining the results of targeted observations, H.E.S.S. has accumulated a large amount of extra-galactic exposure at TeV energies. Due to its large field of view a considerable part of the sky (0.6 sr) has been observed with high sensitivity outside the targeted observation positions. Since this exposure region contains little inherent bias, it is well suited for studies of extra-galactic source populations. Given the correlation between ultra-high energy cosmic rays and nearby extra-galactic objects recently claimed by the Auger collaboration, this unbiased sky sample by H.E.S.S. is of interest since it includes (besides the targeted sources) 63 AGN within 100 Mpc, for which very-high energy gamma-ray flux limits are derived.

  1. Young massive star clusters in nearby galaxies. I. Identification and general properties of cluster systems

    E-Print Network [OSTI]

    Soeren S. Larsen; Tom Richtler

    1999-02-19T23:59:59.000Z

    Using ground-based UBVRI+Halpha CCD photometry we have been carrying out a search for young massive star clusters (YMCs) in a sample consisting of 21 nearby spiral galaxies. We find a large variety concerning the richness of the cluster systems, with some galaxies containing no YMCs at all and others hosting very large numbers of YMCs. Examples of galaxies with poor cluster systems are NGC 300 and NGC 4395, while the richest cluster systems are found in the galaxies NGC 5236, NGC 2997 and NGC 1313. The age distributions of clusters in these galaxies show no obvious peaks, indicating that massive star clusters are formed as an ongoing process rather than in bursts. This is in contrast to what is observed in starbursts and merger galaxies. The radial distributions of clusters follow the Halpha surface brightness. For the galaxies in our sample there is no correlation between the morphological type and the presence of YMCs

  2. THE ACS NEARBY GALAXY SURVEY TREASURY. III. CEPHEIDS IN THE OUTER DISK OF M81

    SciTech Connect (OSTI)

    McCommas, Les P.; Williams, Benjamin F.; Dalcanton, Julianne J.; Davis, Matthew R. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Yoachim, Peter [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Dolphin, Andrew E. [Raytheon Corporation, 870 Winter Street Waltham, MA 02451 (United States)], E-mail: lmccomma@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: ben@astro.washington.edu, E-mail: mrdavis@astro.washington.edu, E-mail: yoachim@astro.as.utexas.edu, E-mail: adolphin@ratheon.com

    2009-06-15T23:59:59.000Z

    The ACS Nearby Galaxy Survey Treasury (ANGST) has acquired deep ACS imaging of a field in the outer disk of the large spiral galaxy M81. These data were obtained over a total of 20 Hubble Space Telescope orbits, providing a baseline long enough to reliably identify Cepheid variable stars in the field. Fundamental mode and first overtone types have been distinguished through comparative fits with corresponding Cepheid light curve templates derived from principal component analysis of confirmed Cepheids in the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and Milky Way. A distance modulus of 27.78 {+-} 0.05 {sub r} {+-} 0.14 {sub s} with a corresponding distance of 3.60 {+-} 0.23 Mpc has been calculated from a sample of 11 fundamental mode and two first overtone Cepheids (assuming an LMC distance modulus of {mu}{sub LMC} = 18.41 {+-} 0.10 {sub r} {+-} 0.13 {sub s})

  3. No nearby counterparts to the moving objects in the Hubble Deep Field

    E-Print Network [OSTI]

    Chris Flynn; J. Sommer-Larsen; B. Fuchs; David S. Graff; Samir Salim; .

    1999-12-14T23:59:59.000Z

    Ibata et al (1999) have recently discovered faint, moving objects in the Hubble Deep Field. The quantity, magnitudes and proper motions of these objects are consistent with old white dwarfs making up the Galactic dark halo. We review a number of ground-based proper motion surveys in which nearby dark halo white dwarfs might be present, if they have the colours and absolute magnitudes proposed. No such objects have been found, whereas we argue here that several times more would be expected than in the Hubble Deep Field. We conclude it is unlikely that hydrogen atmosphere white dwarfs make up a significant fraction of the halo dark matter. No limits can be placed yet on helium atmosphere dwarfs from optical searches.

  4. Structure, dynamical impact and origin of magnetic fields in nearby galaxies in the SKA era

    E-Print Network [OSTI]

    Beck, Rainer; Colafrancesco, Sergio; Dettmar, Ralf-Jürgen; Ferrière, Katia; Fletcher, Andrew; Heald, George; Heesen, Volker; Horellou, Cathy; Krause, Marita; Lou, Yu-Qing; Mao, Sui Ann; Paladino, Rosita; Schinnerer, Eva; Sokoloff, Dmitry; Stil, Jeroen; Tabatabaei, Fatemeh

    2015-01-01T23:59:59.000Z

    Magnetic fields are an important ingredient of the interstellar medium (ISM). Besides their importance for star formation, they govern the transport of cosmic rays, relevant to the launch and regulation of galactic outflows and winds, which in turn are pivotal in shaping the structure of halo magnetic fields. Mapping the small-scale structure of interstellar magnetic fields in many nearby galaxies is crucial to understand the interaction between gas and magnetic fields, in particular how gas flows are affected. Elucidation of the magnetic role in, e.g., triggering star formation, forming and stabilising spiral arms, driving outflows, gas heating by reconnection and magnetising the intergalactic medium has the potential to revolutionise our physical picture of the ISM and galaxy evolution in general. Radio polarisation observations in the very nearest galaxies at high frequencies (>= 3 GHz) and with high spatial resolution (<= 5") hold the key here. The galaxy survey with SKA1 that we propose will also be a...

  5. The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN

    SciTech Connect (OSTI)

    Ajello, M.; /KIPAC, Menlo Park; Alexander, D.M.; /Durham U.; Greiner, J.; /Garching, Max Planck Inst., MPE; Madejski, G.M.; /KIPAC, Menlo Park; Gehrels, N.; /NASA, Goddard; Burlon, D.; /Garching, Max Planck Inst., MPE

    2012-04-02T23:59:59.000Z

    Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this timeframe, BAT detected (in the 15-55 keV band) 720 sources in an all-sky survey of which 428 are associated with AGN, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of {approx}2 larger over similarly complete sets of AGN. Our sample contains (at least) 15 bona-fide Compton-thick AGN and 3 likely candidates. Compton-thick AGN represent a {approx}5% of AGN samples detected above 15 keV. We use the BAT dataset to refine the determination of the LogN-LogS of AGN which is extremely important, now that NuSTAR prepares for launch, towards assessing the AGN contribution to the cosmic X-ray background. We show that the LogN-LogS of AGN selected above 10 keV is now established to a {approx}10% precision. We derive the luminosity function of Compton-thick AGN and measure a space density of 7.9{sub -2.9}{sup +4.1} x 10{sup -5} Mpc{sup -3} for objects with a de-absorbed luminosity larger than 2 x 10{sup 42} erg s{sup -1}. As the BAT AGN are all mostly local, they allow us to investigate the spatial distribution of AGN in the nearby Universe regardless of absorption. We find concentrations of AGN that coincide spatially with the largest congregations of matter in the local ({le} 85 Mpc) Universe. There is some evidence that the fraction of Seyfert 2 objects is larger than average in the direction of these dense regions.

  6. AN INFRARED CENSUS OF DUST IN NEARBY GALAXIES WITH SPITZER (DUSTINGS). I. OVERVIEW

    SciTech Connect (OSTI)

    Boyer, Martha L.; Sonneborn, George [Observational Cosmology Laboratory, Code 665, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); McQuinn, Kristen B. W.; Gehrz, Robert D.; Skillman, Evan [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street SE, University of Minnesota, Minneapolis, MN 55455 (United States); Barmby, Pauline [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada); Bonanos, Alceste Z. [IAASARS, National Observatory of Athens, GR-15236 Penteli (Greece); Gordon, Karl D.; Meixner, Margaret [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Groenewegen, M. A. T. [Royal Observatory of Belgium, Ringlaan 3, B-1180 Brussels (Belgium); Lagadec, Eric [Laboratoire Lagrange, UMR7293, Univ. Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d'Azur, F-06300 Nice (France); Lennon, Daniel [ESA—European Space Astronomy Centre, Apdo. de Correo 78, E-28691 Villanueva de la Cañada, Madrid (Spain); Marengo, Massimo [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Sloan, G. C. [Astronomy Department, Cornell University, Ithaca, NY 14853-6801 (United States); Van Loon, Jacco Th. [Astrophysics Group, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG (United Kingdom); Zijlstra, Albert, E-mail: martha.boyer@nasa.gov [Jodrell Bank Centre for Astrophysics, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom)

    2015-01-01T23:59:59.000Z

    Nearby resolved dwarf galaxies provide excellent opportunities for studying the dust-producing late stages of stellar evolution over a wide range of metallicity (–2.7 ? [Fe/H] ? –1.0). Here, we describe DUSTiNGS (DUST in Nearby Galaxies with Spitzer): a 3.6 and 4.5 ?m post-cryogen Spitzer Space Telescope imaging survey of 50 dwarf galaxies within 1.5 Mpc that is designed to identify dust-producing asymptotic giant branch (AGB) stars and massive stars. The survey includes 37 dwarf spheroidal, 8 dwarf irregular, and 5 transition-type galaxies. This near-complete sample allows for the building of statistics on these rare phases of stellar evolution over the full metallicity range. The photometry is >75% complete at the tip of the red giant branch for all targeted galaxies, with the exception of the crowded inner regions of IC 10, NGC 185, and NGC 147. This photometric depth ensures that the majority of the dust-producing stars, including the thermally pulsing AGB stars, are detected in each galaxy. The images map each galaxy to at least twice the half-light radius to ensure that the entire evolved star population is included and to facilitate the statistical subtraction of background and foreground contamination, which is severe at these wavelengths. In this overview, we describe the survey, the data products, and preliminary results. We show evidence for the presence of dust-producing AGB stars in eight of the targeted galaxies, with metallicities as low as [Fe/H] = –1.9, suggesting that dust production occurs even at low metallicity.

  7. THE NATURE OF STARBURSTS. I. THE STAR FORMATION HISTORIES OF EIGHTEEN NEARBY STARBURST DWARF GALAXIES

    SciTech Connect (OSTI)

    McQuinn, Kristen B. W.; Skillman, Evan D.; Stark, David; Weisz, Daniel [Department of Astronomy, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Dalcanton, Julianne; Williams, Benjamin [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85706 (United States); Hidalgo-RodrIguez, Sebastian [Instituto de Astrofisica de Canarias, VIa Lactea s/n. E38200, La Laguna, Tenerife, Canary Islands (Spain); Holtzman, Jon, E-mail: kmcquinn@astro.umn.ed [Department of Astronomy, New Mexico State University, Box 30001-Department 4500, 1320 Frenger Street, Las Cruces, NM 88003 (United States)

    2010-09-20T23:59:59.000Z

    We use archival Hubble Space Telescope observations of resolved stellar populations to derive the star formation histories (SFHs) of 18 nearby starburst dwarf galaxies. In this first paper, we present the observations, color-magnitude diagrams (CMDs), and the SFHs of the 18 starburst galaxies, based on a homogeneous approach to the data reduction, differential extinction, and treatment of photometric completeness. We adopt a star formation rate (SFR) threshold normalized to the average SFR of the individual system as a metric for classifying starbursts in SFHs derived from resolved stellar populations. This choice facilitates finding not only the currently bursting galaxies but also 'fossil' bursts increasing the sample size of starburst galaxies in the nearby (D < 8 Mpc) universe. Thirteen of the eighteen galaxies are experiencing ongoing bursts and five galaxies show fossil bursts. From our reconstructed SFHs, it is evident that the elevated SFRs of a burst are sustained for hundreds of Myr with variations on small timescales. A long >100 Myr temporal baseline is thus fundamental to any starburst definition or identification method. The longer lived bursts rule out rapid 'self-quenching' of starbursts on global scales. The bursting galaxies' gas consumption timescales are shorter than the Hubble time for all but one galaxy confirming the short-lived nature of starbursts based on fuel limitations. Additionally, we find that the strength of the H{alpha} emission usually correlates with the CMD-based SFR during the last 4-10 Myr. However, in four cases, the H{alpha} emission is significantly less than what is expected for models of starbursts; the discrepancy is due to the SFR changing on timescales of a few Myr. The inherently short timescale of the H{alpha} emission limits identifying galaxies as starbursts based on the current characteristics which may or may not be representative of the recent SFH of a galaxy.

  8. MID-INFRARED IRS SPECTROSCOPY OF NGC 7331: A FIRST LOOK AT THE SPITZER INFRARED NEARBY GALAXIES SURVEY (SINGS) LEGACY

    E-Print Network [OSTI]

    Draine, Bruce T.

    MID-INFRARED IRS SPECTROSCOPY OF NGC 7331: A FIRST LOOK AT THE SPITZER INFRARED NEARBY GALAXIES to 38 m using all modules of Spitzer's Infrared Spectrograph (IRS). A strong new dust emission feature with standard photodissociation region (PDR) models. Either additional PDR heating or shocks are required

  9. The Evolving ISM in the Milky Way & Nearby Galaxies ISM Theory: Gas Phases, Turbulence, and Star Formation

    E-Print Network [OSTI]

    and fills much of the volume near the Galactic midplan, and cold atomic gas, which is organized into denseThe Evolving ISM in the Milky Way & Nearby Galaxies ISM Theory: Gas Phases, Turbulence, and Star modeling efforts have begun to take into account the effects of multiscale, time- dependent processes

  10. Temperature profile for glacial ice at the South Pole: Implications for life in a nearby subglacial lake

    E-Print Network [OSTI]

    Price, P. Buford

    by P. Buford Price, April 22, 2002 Airborne radar has detected 100 lakes under the Antarctic ice cap-induced melting temperature of freshwater ice. To produce the strong radar signal, the frozen lake must consistTemperature profile for glacial ice at the South Pole: Implications for life in a nearby subglacial

  11. FLAME facility: The effect of obstacles and transverse venting on flame acceleration and transition on detonation for hydrogen-air mixtures at large scale

    SciTech Connect (OSTI)

    Sherman, M.P.; Tieszen, S.R.; Benedick, W.B.

    1989-04-01T23:59:59.000Z

    This report describes research on flame acceleration and deflagration-to-detonation transition (DDT) for hydrogen-air mixtures carried out in the FLAME facility, and describes its relevance to nuclear reactor safety. Flame acceleration and DDT can generate high peak pressures that may cause failure of containment. FLAME is a large rectangular channel 30.5 m long, 2.44 m high, and 1.83 m wide. It is closed on the ignition end and open on the far end. The three test variables were hydrogen mole fraction (12--30%), degree of transverse venting (by moving steel top plates---0%, 13%, and 50%), and the absence or presence of certain obstacles in the channel (zero or 33% blockage ratio). The most important variable was the hydrogen mole fraction. The presence of the obstacles tested greatly increased the flame speeds, overpressures, and tendency for DDT compared to similar tests without obstacles. Different obstacle configurations could have greater or lesser effects on flame acceleration and DDT. Large degrees of transverse venting reduced the flame speeds, overpressures, and possibility of DDT. For small degrees of transverse venting (13% top venting), the flame speeds and overpressures were higher than for no transverse venting with reactive mixtures (>18% H/sub 2/), but they were lower with leaner mixtures. The effect of the turbulence generated by the flow out the vents on increasing flame speed can be larger than the effect of venting gas out of the channel and hence reducing the overpressure. With no obstacles and 50% top venting, the flame speeds and overpressures were low, and there was no DDT. For all other cases, DDT was observed above some threshold hydrogen concentration. DDT was obtained at 15% H/sub 2/ with obstacles and no transverse venting. 67 refs., 62 figs.

  12. Vertical broad-line region structure in nearby active galactic nuclei

    E-Print Network [OSTI]

    Kollatschny, W

    2013-01-01T23:59:59.000Z

    Broad emission lines are emitted in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). This region is spatially not resolved. We intend to get information on the structure and geometry of this broad emitting line region (BLR) based on line profile observations. We model the rotational and turbulent velocities in the line-emitting regions based on observed full-width at half maximum line values (FWHM) and {\\sigma}_{line} of the variable broad emission lines in four nearby AGN: NGC 3783, NGC 7469, NGC 5548, and 3C 390.3. On the basis of these velocities, we estimate the height of the line-emitting regions above the midplane in context with their distances from the center. The H{\\beta} lines are emitted in a more flattened configuration above the midplane in comparison to the highly ionized lines. The H{\\beta} lines originate at heights of 0.7 to 1.6 light-days and at distances of 1.4 to 24 light-days with height/distance (H/R) ratios of only 0.07 to 0.5. The highly ioni...

  13. Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

    SciTech Connect (OSTI)

    Abreu, P.; /Lisbon, IST; Aglietta, M.; /Turin U. /INFN, Turin; Ahn, E.J.; /Fermilab; Allard, D.; /APC, Paris; Allekotte, I.; /Centro Atomico Bariloche; Allen, J.; /New York U.; Alvarez Castillo, J.; /Mexico U., ICN; Alvarez-Muniz, J.; /Santiago de Compostela U.; Ambrosio, M.; /INFN, Naples /Naples U.; Aminaei, A.; /Nijmegen U., IMAPP; Anchordoqui, L.; /Wisconsin U., Milwaukee /Lisbon, IST

    2010-06-01T23:59:59.000Z

    Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuzmin energy threshold, 6 x 10{sup 19} eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1{sup o} from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38{sub -6}{sup +7})%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69{sub -13}{sup +11})%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.

  14. An astrometric companion to the nearby metal-poor, low-mass star LHS 1589

    E-Print Network [OSTI]

    Sebastien Lepine; R. Michael Rich; Michael M. Shara; Kelle L. Cruz; Andrew Skemer

    2007-07-20T23:59:59.000Z

    We report the discovery of a companion to the high proper motion star LHS 1589, a nearby high-velocity, low-mass subdwarf. The companion (LHS 1589B) is located 0.224+/-0.004" to the southwest of the primary (LHS 1589A), and is 0.5 magnitude fainter than the primary in the K_s band. The pair was resolved with the IRCAL infrared camera at Lick Observatory, operating with the Laser Guide Star Adaptive Optics system. A low-resolution spectrum of the unresolved pair obtained at the MDM observatory shows the source to be consistent with a cool subdwarf of spectral subtype sdK7.5. A photometric distance estimate places the metal-poor system at a distance d=81+/-18 parsecs from the Sun. We also measure a radial velocity V_rad=67+/-8 km/s which, together with the proper motion and estimated distance, suggests that the pair is roaming the inner Galactic halo on a highly eccentric orbit. With a projected orbital separation s=18.1+/-4.8 AU, and a crude estimate of the system's total mass, we estimate the orbital period of the system to be in the range 75 yr metal-poor, low-mass stars.

  15. Effervescent heating: constraints from nearby cooling flow clusters observed with XMM-Newton

    E-Print Network [OSTI]

    Rocco Piffaretti; Jelle Kaastra

    2006-05-15T23:59:59.000Z

    We have used deprojected radial density and temperature profiles of a sample of 16 nearby CF clusters observed with XMM-Newton to test whether the effervescent heating model can satisfactorily explain the dynamics of CF clusters. For each cluster we derived the required extra heating as a function of cluster-centric distance for various values of the unknown parameters $\\dot M$ (mass deposition rate) and $f_c$ (conduction efficiency). We fitted the extra heating curve using the AGN effervescent heating function and derived the AGN parameters $L$ (the time-averaged luminosity) and $r_0$ (the scale radius where the bubbles start rising in the ICM). While we do not find any solution with the effervescent heating model for only one object, we do show that AGN and conduction heating are not cooperating effectively for half of the objects in our sample. For most of the clusters we find that, when a comparison is possible, the derived AGN scale radius $r_0$ and the observed AGN jet extension have the same order of magnitude. The AGN luminosities required to balance radiative losses are substantially lowered if the fact that the AGN deposits energy within a finite volume is taken into account. For the Virgo cluster, we find that the AGN power derived from the effervescent heating model is in good agreement with the observed jet power.

  16. Starburst Anatomy: Stellar and Nebular Properties of Nearby Giant HII Regions

    E-Print Network [OSTI]

    William H. Waller

    1996-12-27T23:59:59.000Z

    Resolution of nearby giant HII regions into their stellar and nebular constituents provides fundamental insights for interpreting more distant and powerful starburst activity. The following summarizes recent advances in our understanding of the stellar populations and nebular energetics associated with giant HII regions. Photometry and spectroscopy of ionizing clusters in the Galaxy, LMC, and SMC reveal no significant relation between metallicity and the slope of the power-law initial mass function (IMF). HST/WFPC2 photometry of 3 giant HII regions in M33 also does not show any consistent trend involving metal abundance and IMF slope -- contrary to predictions based on emission-line ratios. The upper stellar mass limit appears to be constrained more by cluster age than by anything else. The ionizing luminosities from some of the resolved stellar populations are insufficient to account for the ionization rates inferred from measurements of the composite (integrated) H-alpha emission. Absorption of stellar EUV emission by nebular dust grains would only amplify these photoionizing shortfalls. Leakage of ionizing photons from the HII regions would further exacerbate the situation. What then is providing the additional ionization? Prospects for higher stellar EUV luminosities and/or alternative sources of nebular ionization (e.g. shocks) are evaluated with this question in mind.

  17. Discretization error estimation and exact solution generation using the method of nearby problems.

    SciTech Connect (OSTI)

    Sinclair, Andrew J. (Auburn University Auburn, AL); Raju, Anil (Auburn University Auburn, AL); Kurzen, Matthew J. (Virginia Tech Blacksburg, VA); Roy, Christopher John (Virginia Tech Blacksburg, VA); Phillips, Tyrone S. (Virginia Tech Blacksburg, VA)

    2011-10-01T23:59:59.000Z

    The Method of Nearby Problems (MNP), a form of defect correction, is examined as a method for generating exact solutions to partial differential equations and as a discretization error estimator. For generating exact solutions, four-dimensional spline fitting procedures were developed and implemented into a MATLAB code for generating spline fits on structured domains with arbitrary levels of continuity between spline zones. For discretization error estimation, MNP/defect correction only requires a single additional numerical solution on the same grid (as compared to Richardson extrapolation which requires additional numerical solutions on systematically-refined grids). When used for error estimation, it was found that continuity between spline zones was not required. A number of cases were examined including 1D and 2D Burgers equation, the 2D compressible Euler equations, and the 2D incompressible Navier-Stokes equations. The discretization error estimation results compared favorably to Richardson extrapolation and had the advantage of only requiring a single grid to be generated.

  18. Fundamental Parameters of Nearby Stars from the Comparison with Evolutionary Calculations: Masses, Radii and Effective temperatures

    E-Print Network [OSTI]

    Carlos Allende Prieto; David L. Lambert

    1999-11-02T23:59:59.000Z

    The Hipparcos mission has made it possible to constrain the positions of nearby field stars in the colour-magnitude diagram with very high accuracy. These positions can be compared with the predictions of stellar evolutionary calculations to provide information on the basic parameters of the stars: masses, radii, effective temperatures, ages, and chemical composition. The degeneracy between mass, age, and metallicity is not so large as to prevent a reliable estimate of masses, radii and effective temperatures, at least for stars of solar metallicity. The evolutionary models of Bertelli et al. (1994) predict those parameters finely, and furthermore, the applied transformation from the theoretical (log g-Teff) to the observational (Mv-B-V) plane is precise enough to derive radii with an uncertainty of ~ 6%, masses within ~ 8%, and Teffs within ~ 2% for a certain range of the stellar parameters. This is demonstrated by means of comparison with the measurements in eclipsing binaries and the InfraRed Flux Method. The application of the interpolation procedure in the theoretical isochrones to the stars within 100 pc from the Sun observed with Hipparcos provides estimates for 17,219 stars

  19. A Chandra study of particle acceleration in the multiple hotspots of nearby radio galaxies

    E-Print Network [OSTI]

    M. J. Hardcastle; J. H. Croston; R. P. Kraft

    2007-07-19T23:59:59.000Z

    We present Chandra observations of a small sample of nearby classical double radio galaxies which have more than one radio hotspot in at least one of their lobes. The X-ray emission from the hotspots of these comparatively low-power objects is expected to be synchrotron in origin, and therefore to provide information about the locations of high-energy particle acceleration. In some models of the relationship between the jet and hotspot the hotspots that are not the current jet termination point should be detached from the energy supply from the active nucleus and therefore not capable of accelerating particles to high energies. We find that in fact some secondary hotspots are X-ray sources, and thus probably locations for high-energy particle acceleration after the initial jet termination shock. In detail, though, we show that the spatial structures seen in X-ray are not consistent with naive expectations from a simple shock model: the current locations of the acceleration of the highest-energy observable particles in powerful radio galaxies need not be coincident with the peaks of radio or even optical emission.

  20. A Search for "Dwarf" Seyfert Nuclei. VI. Properties of Emission-Line Nuclei in Nearby Galaxies

    E-Print Network [OSTI]

    Luis C. Ho; Alexei V. Filippenko; Wallace L. W. Sargent

    2002-10-02T23:59:59.000Z

    We use the database from Paper III to quantify the global and nuclear properties of emission-line nuclei in the Palomar spectroscopic survey of nearby galaxies. We show that the host galaxies of Seyferts, LINERs, and transition objects share remarkably similar large-scale properties and local environments. The distinguishing traits emerge on nuclear scales. Compared with LINERs, Seyfert nuclei are an order of magnitude more luminous and exhibit higher electron densities and internal extinction. We suggest that Seyfert galaxies possess characteristically more gas-rich circumnuclear regions, and hence a more abundant fuel reservoir and plausibly higher accretion rates. The differences between the ionization state of the narrow emission-line regions of Seyferts and LINERs can be partly explained by the differences in their nebular properties. Transition-type objects are consistent with being composite (LINER/\\hii) systems. With very few exceptions, the stellar population within the central few hundred parsecs of the host galaxies is uniformly old, a finding that presents a serious challenge to starburst or post-starburst models for these objects. Seyferts and LINERs have virtually indistinguishable velocity fields as inferred from their line widths and line asymmetries. All three classes of objects obey a strong correlation between line width and line luminosity. We argue that the angular momentum content of circumnuclear gas may be an important factor in determining whether a nucleus becomes active. Finally, we discuss some possible complications for the unification model of Seyfert galaxies posed by our observations. (Abridged)

  1. Temperature profiles of a representative sample of nearby X-ray galaxy clusters

    E-Print Network [OSTI]

    G. W. Pratt; H. Boehringer; J. H. Croston; M. Arnaud; S. Borgani; A. Finoguenov; R. F. Temple

    2006-09-18T23:59:59.000Z

    A study of the structural and scaling properties of the temperature distribution of the hot, X-ray emitting intra-cluster medium of galaxy clusters, and its dependence on dynamical state, can give insights into the physical processes governing the formation and evolution of structure. We analyse the X-ray temperature profiles from XMM-Newton observations of 15 nearby (z temperature range from 2.5 keV to 8.5 keV, and present a variety of X-ray morphologies. We derive accurate projected temperature profiles to ~ 0.5 R_200, and compare structural properties (outer slope, presence of cooling core) with a quantitative measure of the X-ray morphology as expressed by power ratios. We also compare the results to recent cosmological numerical simulations. Once the temperature profiles are scaled by an average cluster temperature (excluding the central region) and the estimated virial radius, the profiles generally decline in the region 0.1 R_200 temperature decrement appear to be slightly more regular. The present results lend further evidence to indicate that clusters are a regular population, at least outside the core region.

  2. SMT CO (2-1) Observations of Nearby Star-Forming Galaxies

    E-Print Network [OSTI]

    Jiang, Xue-Jian; Gu, Qiusheng; Wang, Junzhi; Zhang, Zhi-Yu

    2014-01-01T23:59:59.000Z

    We present CO $J$=2-1 observations towards 32 nearby gas-rich star-forming galaxies selected from the ALFALFA and WISE catalogs, using the Sub-millimeter Telescope. Our sample is selected to be dominated by intermediate-$M_{\\rm *}$ galaxies. The scaling-relations between molecular gas, atomic gas and galactic properties (stellar mass, NUV$- r$ and WISE color W3$-$W2) are examined and discussed. Our results show that (1). In the galaxies with stellar mass $M_{\\rm *}$ $\\leqslant 10^{10}$ $M_{\\odot}$, HI fraction ($f_{\\rm HI}$ $\\equiv$ $M_{\\rm HI}$/$M_{\\rm *}$) is significantly higher than that of more massive galaxies, while H$_2$ gas fraction ($f_{\\rm H_2}$ $\\equiv$ $M_{\\rm H_2}$/$M_{\\rm *}$) remain nearly unchanged. (2). Comparing with $f_{\\rm H_2}$, $f_{\\rm HI}$ correlates better with both $M_{\\rm *}$ and NUV$- r$. (3). A new parameter, WISE color W3$-$W2 (12\\,$\\mu$m$-$4.6\\,$\\mu$m) is introduced, which is similar to NUV$- r$ in tracing star formation activity, and we find that W3$-$W2 has a tighter anti-corr...

  3. HOST GALAXY PROPERTIES AND HUBBLE RESIDUALS OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY

    SciTech Connect (OSTI)

    Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

    2013-06-20T23:59:59.000Z

    We examine the relationship between Type Ia supernova (SN Ia) Hubble residuals and the properties of their host galaxies using a sample of 115 SNe Ia from the Nearby Supernova Factory. We use host galaxy stellar masses and specific star formation rates fitted from photometry for all hosts, as well as gas-phase metallicities for a subset of 69 star-forming (non-active galactic nucleus) hosts, to show that the SN Ia Hubble residuals correlate with each of these host properties. With these data we find new evidence for a correlation between SN Ia intrinsic color and host metallicity. When we combine our data with those of other published SN Ia surveys, we find the difference between mean SN Ia brightnesses in low- and high-mass hosts is 0.077 {+-} 0.014 mag. When viewed in narrow (0.2 dex) bins of host stellar mass, the data reveal apparent plateaus of Hubble residuals at high and low host masses with a rapid transition over a short mass range (9.8 {<=} log (M{sub *}/M{sub Sun }) {<=} 10.4). Although metallicity has been a favored interpretation for the origin of the Hubble residual trend with host mass, we illustrate how dust in star-forming galaxies and mean SN Ia progenitor age both evolve along the galaxy mass sequence, thereby presenting equally viable explanations for some or all of the observed SN Ia host bias.

  4. HOST GALAXIES OF TYPE Ia SUPERNOVAE FROM THE NEARBY SUPERNOVA FACTORY

    SciTech Connect (OSTI)

    Childress, M.; Aldering, G.; Aragon, C.; Bailey, S.; Fakhouri, H. K.; Hsiao, E. Y.; Kim, A. G.; Loken, S. [Physics Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Antilogus, P.; Bongard, S.; Canto, A.; Cellier-Holzem, F.; Guy, J. [Laboratoire de Physique Nucleaire et des Hautes Energies, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 place Jussieu, F-75252 Paris Cedex 05 (France); Baltay, C. [Department of Physics, Yale University, New Haven, CT 06250-8121 (United States); Buton, C.; Kerschhaggl, M.; Kowalski, M. [Physikalisches Institut, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Chotard, N.; Copin, Y.; Gangler, E. [Universite de Lyon, F-69622, Lyon (France); Universite de Lyon 1, Villeurbanne (France); CNRS/IN2P3, Institut de Physique Nucleaire de Lyon (France); and others

    2013-06-20T23:59:59.000Z

    We present photometric and spectroscopic observations of galaxies hosting Type Ia supernovae (SNe Ia) observed by the Nearby Supernova Factory. Combining Galaxy Evolution Explorer (GALEX) UV data with optical and near-infrared photometry, we employ stellar population synthesis techniques to measure SN Ia host galaxy stellar masses, star formation rates (SFRs), and reddening due to dust. We reinforce the key role of GALEX UV data in deriving accurate estimates of galaxy SFRs and dust extinction. Optical spectra of SN Ia host galaxies are fitted simultaneously for their stellar continua and emission lines fluxes, from which we derive high-precision redshifts, gas-phase metallicities, and H{alpha}-based SFRs. With these data we show that SN Ia host galaxies present tight agreement with the fiducial galaxy mass-metallicity relation from Sloan Digital Sky Survey (SDSS) for stellar masses log(M{sub *}/M{sub Sun }) > 8.5 where the relation is well defined. The star formation activity of SN Ia host galaxies is consistent with a sample of comparable SDSS field galaxies, though this comparison is limited by systematic uncertainties in SFR measurements. Our analysis indicates that SN Ia host galaxies are, on average, typical representatives of normal field galaxies.

  5. Central Mass Profiles of the Nearby Cool-core Galaxy Clusters Hydra A and A478

    E-Print Network [OSTI]

    Okabe, N; Tamura, T; Fujita, Y; Takizawa, M; Matsushita, K; Fukazawa, Y; Futamase, T; Kawaharada, M; Miyazaki, S; Mochizuki, Y; Nakazawa, K; Ohashi, T; Ota, N; Sasaki, T; Sato, K; Tam, S I

    2015-01-01T23:59:59.000Z

    We perform a weak-lensing study of the nearby cool-core galaxy clusters, Hydra A ($z=0.0538$) and A478 ($z=0.0881$), of which brightest cluster galaxies (BCGs) host powerful activities of active galactic nuclei (AGNs). For each cluster, the observed tangential shear profile is well described either by a single Navarro--Frenk--White model or a two-component model including the BCG as an unresolved point mass. For A478, we determine the BCG and its host-halo masses from a joint fit to weak-lensing and stellar photometry measurements. We find that the choice of initial mass functions (IMFs) can introduce a factor of two uncertainty in the BCG mass, whereas the BCG host halo mass is well constrained by data. We perform a joint analysis of weak-lensing and stellar kinematics data available for the Hydra A cluster, which allows us to constrain the central mass profile without assuming specific IMFs.We find that the central mass profile ($r<300$ kpc) determined from the joint analysis is in excellent agreement wi...

  6. Regulation of Tall Structures (Indiana)

    Broader source: Energy.gov [DOE]

    A permit from the Department of Transportation is required for the construction or alteration of any structure higher than 200 feet above ground level, or structures near airports, highways,...

  7. The Obstacle Version of the Geometric Dynamic Programming Principle: Application to the Pricing of American Options Under Constraints

    SciTech Connect (OSTI)

    Bouchard, Bruno, E-mail: bouchard@ceremade.dauphine.fr; Vu, Thanh Nam, E-mail: thanh@ceremade.dauphine.f [Universite Paris Dauphine, CEREMADE (France)

    2010-04-15T23:59:59.000Z

    We provide an obstacle version of the Geometric Dynamic Programming Principle of Soner and Touzi (J. Eur. Math. Soc. 4:201-236, 2002) for stochastic target problems. This opens the doors to a wide range of applications, particularly in risk control in finance and insurance, in which a controlled stochastic process has to be maintained in a given set on a time interval [0,T]. As an example of application, we show how it can be used to provide a viscosity characterization of the super-hedging cost of American options under portfolio constraints, without appealing to the standard dual formulation from mathematical finance. In particular, we allow for a degenerate volatility, a case which does not seem to have been studied so far in this context.

  8. WISEP J180026.60+013453.1: A NEARBY LATE-L DWARF NEAR THE GALACTIC PLANE

    SciTech Connect (OSTI)

    Gizis, John E.; Castro, Philip J. [Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Burgasser, Adam J. [Center for Astrophysics and Space Science, University of California San Diego, La Jolla, CA 92093 (United States); Faherty, Jacqueline K.; Shara, Michael M. [Department of Astrophysics, American Museum of Natural History, New York, NY 10034 (United States)

    2011-11-15T23:59:59.000Z

    We report a nearby L7.5 dwarf discovered using the Preliminary Data Release of the Wide-field Infrared Survey Explorer (WISE) and the Two Micron All Sky Survey. WISEP J180026.60+013453.1 has a motion of 0.42 arcsec yr{sup -1} and an estimated distance of 8.8 {+-} 1.0 pc. With this distance, it currently ranks as the sixth closest known L dwarf, although a trigonometric parallax is needed to confirm this distance. It was previously overlooked because it lies near the Galactic plane (b = 12 Degree-Sign ). As a relatively bright and nearby late L dwarf with normal near-infrared colors, W1800+0134 will serve as a benchmark for studies of cloud-related phenomena in cool substellar atmospheres.

  9. FINDING {eta} CAR ANALOGS IN NEARBY GALAXIES USING SPITZER. I. CANDIDATE SELECTION

    SciTech Connect (OSTI)

    Khan, Rubab; Stanek, K. Z.; Kochanek, C. S., E-mail: khan@astronomy.ohio-state.edu, E-mail: kstanek@astronomy.ohio-state.edu, E-mail: ckochanek@astronomy.ohio-state.edu [Department of Astronomy, The Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States)

    2013-04-10T23:59:59.000Z

    The late-stage evolution of the most massive stars such as {eta} Carinae is controlled by the effects of mass loss, which may be dominated by poorly understood eruptive mass ejections. Understanding this population is challenging because no true analogs of {eta} Car have been clearly identified in the Milky Way or other galaxies. We utilize Spitzer IRAC images of seven nearby ({approx}< 4 Mpc) galaxies to search for such analogs. We find 34 candidates with a flat or rising mid-IR spectral energy distributions toward longer mid-infrared wavelengths that emit >10{sup 5} L{sub Sun} in the IRAC bands (3.6 to 8.0 {mu}m) and are not known to be background sources. Based on our estimates for the expected number of background sources, we expect that follow-up observations will show that most of these candidates are not dust enshrouded massive stars, with an expectation of only 6 {+-} 6 surviving candidates. Since we would detect true analogs of {eta} Car for roughly 200 years post-eruption, this implies that the rate of eruptions like {eta} Car is less than the core-collapse supernova rate. It is possible, however, that every M > 40 M{sub Sun} star undergoes such eruptions given our initial results. In Paper II we will characterize the candidates through further analysis and follow-up observations, and there is no barrier to increasing the galaxy sample by an order of magnitude. The primary limitation of the present search is that Spitzer's resolution limits us to the shorter wavelength IRAC bands. With the James Webb Space Telescope, such surveys can be carried out at the far more optimal wavelengths of 10-30 {mu}m, allowing identification of {eta} Car analogs for millennia rather than centuries post-eruption.

  10. In situ measurements of rock salt permeability changes due to nearby excavation

    SciTech Connect (OSTI)

    Stormont, J.C. (Sandia National Labs., Albuquerque, NM (United States)); Howard, C.L. (RE/SPEC, Inc., Carlsbad, NM (United States)); Daemen, J.J.K. (Nevada Univ., Reno, NV (United States). Mackay School of Mines)

    1991-07-01T23:59:59.000Z

    The Small-Scale Mine-By was an in situ experiment to measure changes in brine and gas permeability of rock salt as a result of nearby excavation. A series of small-volume pressurized brine- and gas-filled test intervals were established 8 m beneath the floor of Room L1 in the WIPP underground. The test intervals were isolated in the bottom of the 4.8-cm diameter monitoring boreholes with inflatable rubber packers, and are initially pressurized to about 2 MPa. Both brine- and gas-filled test intervals were located 1.25, 1.5, 2, 3, and 4 r from the center of a planned large-diameter hole, where r is the radius of the large-diameter hole. Prior to the drilling of the large-diameter borehole, the responses of both the brine- and gas-filled test intervals were consistent with the formation modeled as a very low permeability, low porosity porous medium with a significant pore (brine) pressure and no measurable gas permeability. The drilling of the mine-by borehole created a zone of dilated, partially saturated rock out to about 1.5 r. The formation pressure increases from near zero at 1.5 r to the pre-excavation value at 4 r. Injection tests reveal a gradient of brine permeabilities from 5 {times} 10{sup {minus}18} m{sup 2} at 1.25 r to about the pre-excavation value (10{sup {minus}21} m{sup 2}) by 3 r. Gas-injection tests reveal measurable gas permeability is limited to within 1.5 r. 17 refs., 24 figs., 6 tabs.

  11. LONG-TERM OPTICAL CONTINUUM COLOR VARIABILITY OF NEARBY ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Sakata, Yu; Minezaki, Takeo; Yoshii, Yuzuru; Uchimoto, Yuka Katsuno; Sugawara, Shota [Institute of Astronomy, School of Science, University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan); Kobayashi, Yukiyasu [National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Koshida, Shintaro [Department of Astronomy, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0013 (Japan); Aoki, Tsutomu; Tomita, Hiroyuki [Kiso Observatory, Institute of Astronomy, School of Science, University of Tokyo, 10762-30 Mitake, Kiso, Nagano 397-0101 (Japan); Enya, Keigo; Suganuma, Masahiro, E-mail: yusakata@ioa.s.u-tokyo.ac.j [Institute of Space and Astronomical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan)

    2010-03-01T23:59:59.000Z

    We examine whether the spectral energy distribution of optical continuum emission of active galactic nuclei (AGNs) changes during flux variation, based on accurate and frequent monitoring observations of 11 nearby Seyfert galaxies and QSOs carried out in the B, V, and I bands for seven years by the MAGNUM telescope. The multi-epoch flux data in any two different bands obtained on the same night show a very tight linear flux-to-flux relationship for all target AGNs. The flux of the host galaxy within the photometric aperture is carefully estimated by surface brightness fitting to available high-resolution Hubble Space Telescope images and MAGNUM images. The flux of narrow emission lines in the photometric bands is also estimated from available spectroscopic data. We find that the non-variable component of the host galaxy plus narrow emission lines for all target AGNs is located on the fainter extension of the linear regression line of multi-epoch flux data in the flux-to-flux diagram. This result strongly indicates that the spectral shape of AGN continuum emission in the optical region ({approx}4400-7900 A) does not systematically change during flux variation. The trend of spectral hardening that optical continuum emission becomes bluer as it becomes brighter, which has been reported by many studies, is therefore interpreted as the domination of the variable component of the nearly constant spectral shape of an AGN as it brightens over the non-variable component of the host galaxy plus narrow lines, which is usually redder than AGN continuum emission.

  12. BAYESIAN ANALYSIS TO IDENTIFY NEW STAR CANDIDATES IN NEARBY YOUNG STELLAR KINEMATIC GROUPS

    SciTech Connect (OSTI)

    Malo, Lison; Doyon, Rene; Lafreniere, David; Artigau, Etienne; Gagne, Jonathan; Baron, Frederique [Departement de physique and Observatoire du Mont-Megantic, Universite de Montreal, Montreal, QC H3C 3J7 (Canada)] [Departement de physique and Observatoire du Mont-Megantic, Universite de Montreal, Montreal, QC H3C 3J7 (Canada); Riedel, Adric, E-mail: malo@astro.umontreal.ca, E-mail: doyon@astro.umontreal.ca, E-mail: david@astro.umontreal.ca, E-mail: artigau@astro.umontreal.ca, E-mail: gagne@astro.umontreal.ca, E-mail: baron@astro.umontreal.ca, E-mail: riedel@phy-astr.gsu.edu [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States)] [Department of Astrophysics, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024 (United States)

    2013-01-10T23:59:59.000Z

    We present a new method based on a Bayesian analysis to identify new members of nearby young kinematic groups. The analysis minimally takes into account the position, proper motion, magnitude, and color of a star, but other observables can be readily added (e.g., radial velocity, distance). We use this method to find new young low-mass stars in the {beta} Pictoris and AB Doradus moving groups and in the TW Hydrae, Tucana-Horologium, Columba, Carina, and Argus associations. Starting from a sample of 758 mid-K to mid-M (K5V-M5V) stars showing youth indicators such as H{alpha} and X-ray emission, our analysis yields 214 new highly probable low-mass members of the kinematic groups analyzed. One is in TW Hydrae, 37 in {beta} Pictoris, 17 in Tucana-Horologium, 20 in Columba, 6 in Carina, 50 in Argus, 32 in AB Doradus, and the remaining 51 candidates are likely young but have an ambiguous membership to more than one association. The false alarm rate for new candidates is estimated to be 5% for {beta} Pictoris and TW Hydrae, 10% for Tucana-Horologium, Columba, Carina, and Argus, and 14% for AB Doradus. Our analysis confirms the membership of 58 stars proposed in the literature. Firm membership confirmation of our new candidates will require measurement of their radial velocity (predicted by our analysis), parallax, and lithium 6708 A equivalent width. We have initiated these follow-up observations for a number of candidates, and we have identified two stars (2MASSJ01112542+1526214, 2MASSJ05241914-1601153) as very strong candidate members of the {beta} Pictoris moving group and one strong candidate member (2MASSJ05332558-5117131) of the Tucana-Horologium association; these three stars have radial velocity measurements confirming their membership and lithium detections consistent with young age.

  13. XMM-Newton Studies of the Source Population and the Hot Interstellar Medium in Nearby Galaxies

    E-Print Network [OSTI]

    W. Pietsch

    2002-12-20T23:59:59.000Z

    First results of X-ray source population studies in nearby galaxies show the potential of XMM-Newton observations. I will report on first XMM-Newton M31 results and on three of our XMM-Newton projects, an X-ray source population study in the Magellanic Clouds (MCs), a deep raster survey of M33, and an investigation of the hot interstellar medium (ISM) in the halo of edge-on galaxies. XMM-Newton results on several other galaxies and sources within are presented by other authors in these proceedings. Our MC study is build up of deep pointings probing MC sources down to 10^33 erg s^-1 and shallower pointings to confirm candidates from our ROSAT derived lists of X-ray binaries, super-soft sources, and supernova remnants. First XMM-Newton detections of a 455 s pulsar in the Small Magellanic Cloud and the results of the Large Magellanic Cloud deep field confirm the validity of our strategy. Our M33 raster pointing aims for luminosities as low as 10^35 erg s^-1, a factor of 10 below the sensitivity limit of the ROSAT observations. The survey will allow us to characterize the sources using extent, spectra, hardness ratios and time variability to build up an unprecedented census of the X-ray source content of M33. Of specific interest are the active source in the nuclear area and the diffuse emission in the inner disk. XMM-Newton observations of the active galaxy NGC 3079 and of the starburst galaxy NGC 253 are used to characterize the point-like sources and the hot ISM in the disk and from the halo of these galaxies.

  14. The ESO Nearby Abell Cluster Survey VIII. Morphological and spectral classification of galaxies

    E-Print Network [OSTI]

    T. Thomas; P. Katgert

    2005-10-10T23:59:59.000Z

    We have determined the morphological types of 2295 galaxies from the ESO Nearby Abell Cluster Survey (ENACS) from CCD images made with the Dutch telescope on La Silla. The reliability of our classification appears to be quite comparable to that of other classifiers. Recalibration of the ENACS spectral classification shows that early- and late- type galaxies can be distinguished from their spectra with 83% reliability. Ellipticals and S0 galaxies cannot be distinguished spectrally, while spectral classification of late spirals has a reliability of 70%. We derive average pseudo-colors and linestrengths from the ENACS spectra for the galaxies of different morphological types, considering bright (M -20) subsets of the galaxies without emission lines (non-ELG) separately. We find a strong and significant correlation between the average color and the average strength of the metal absorption lines. The average metallicity decreases and the average color gets bluer towards later Hubble type. In each morphological class the faint galaxies are bluer and less metal-rich than the bright ones. This extends the well-established color-magnitude relation of early-type galaxies to (late) spirals. Bright early spirals may, on average, have somewhat stronger H-delta absorption than the other galaxies, which could be due to recent starformation. The galaxies with emission lines (ELG) have a bluer spectral continuum than the non-ELG, and the amount of blueing hardly depends on morphological type. The fraction of ELG depends strongly on morphological type but it varies very little with projected distance from the cluster center.

  15. Starbursts and the triggering of the activity in nearby powerful radio galaxies

    E-Print Network [OSTI]

    C. Tadhunter; T. G. Robinson; R. M. Gonzalez Delgado; K. Wills; R. Morganti

    2004-10-05T23:59:59.000Z

    We present high quality long-slit spectra for three nearby powerful radio galaxies 3C293, 3C305, PKS1345+12. These were taken with the aim of characterising the young stellar populations (YSP), and thereby investigating the evolution of the host galaxies, as well as the events that triggered the activity. Isochrone spectral synthesis modelling of the wide wavelength coverage spectra of nuclear and off-nuclear continuum-emitting regions have been used to estimate the ages, masses and luminosities of the YSP component, taking full account of reddening effects and potential contamination by activity-related components. We find that the YSP make a substantial contribution to the continuum flux in the off-nuclear regions on a radial scale of 1 - 20kpc in all three objects. Moreover, in two objects we find evidence for reddened post-starburst stellar populations in the near-nuclear regions of the host galaxies. The YSP are relatively old (0.1- 2Gyr), massive and make up a large proportion (~1 - 50%) of the total stellar mass in the regions of galaxies sampled by the observations. Overall, these results are consistent with the idea that AGN activity in some radio galaxies is triggered by major gas-rich mergers. Therefore, these radio galaxies form part of the subset of early-type galaxies that is evolving most rapidly in the local universe. Intriguingly, the results also suggest that the radio jets are triggered relatively late in the merger sequence, and that there is an evolutionary link between radio galaxies and luminous/ultra-luminous infrared galaxies.

  16. THE ACS NEARBY GALAXY SURVEY TREASURY. XI. THE REMARKABLY UNDISTURBED NGC 2403 DISK

    SciTech Connect (OSTI)

    Williams, Benjamin F.; Dalcanton, Julianne J.; Stilp, Adrienne; Radburn-Smith, David [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Dolphin, Andrew [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85706 (United States); Skillman, Evan D., E-mail: ben@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: adrienne@astro.washington.edu, E-mail: dolphin@raytheon.com, E-mail: skillman@astro.umn.edu [Department of Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States)

    2013-03-10T23:59:59.000Z

    We present detailed analysis of color-magnitude diagrams of NGC 2403, obtained from a deep (m {approx}< 28) Hubble Space Telescope (HST) Wide Field Planetary Camera 2 observation of the outer disk of NGC 2403, supplemented by several shallow (m {approx}< 26) HST Advanced Camera for Surveys fields. We derive the spatially resolved star formation history of NGC 2403 out to 11 disk scale lengths. In the inner portions of the galaxy, we compare the recent star formation rates (SFRs) we derive from the resolved stars with those measured using GALEX FUV + Spitzer 24{mu} fluxes, finding excellent agreement between the methods. Our measurements also show that the radial gradient in recent SFR mirrors the disk exponential profile to 11 scale lengths with no break, extending to SFR densities a factor of {approx}100 lower than those that can be measured with GALEX and Spitzer ({approx}2 Multiplication-Sign 10{sup -6} M{sub Sun} yr{sup -1} kpc{sup -2}). Furthermore, we find that the cumulative stellar mass of the disk was formed at similar times at all radii. We compare these characteristics of NGC 2403 to those of its ''morphological twins'', NGC 300 and M 33, showing that the structure and age distributions of the NGC 2403 disk are more similar to those of the relatively isolated system NGC 300 than to those of the Local Group analog M 33. We also discuss the environments and HI morphologies of these three nearby galaxies, comparing them to integrated light studies of larger samples of more distant galaxy disks. Taken together, the physical properties and evolutionary history of NGC 2403 suggest that the galaxy has had no close encounters with other M 81 group members and may be falling into the group for the first time.

  17. OBSERVATIONAL CONSTRAINTS ON THE MOLECULAR GAS CONTENT IN NEARBY STARBURST DWARF GALAXIES

    SciTech Connect (OSTI)

    McQuinn, Kristen B. W.; Skillman, Evan D. [Department of Astronomy, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dalcanton, Julianne J.; Weisz, Daniel R.; Williams, Benjamin F. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Dolphin, Andrew E. [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Holtzman, Jon, E-mail: kmcquinn@astro.umn.edu [Department of Astronomy, New Mexico State University, Box 30001, Department 4500, 1320 Frenger Street, Las Cruces, NM 88003 (United States)

    2012-06-01T23:59:59.000Z

    Using star formation histories derived from optically resolved stellar populations in 19 nearby starburst dwarf galaxies observed with the Hubble Space Telescope, we measure the stellar mass surface densities of stars newly formed in the bursts. By assuming a star formation efficiency (SFE), we then calculate the inferred gas surface densities present at the onset of the starbursts. Assuming an SFE of 1%, as is often assumed in normal star-forming galaxies, and assuming that the gas was purely atomic, translates to very high H I surface densities ({approx}10{sup 2}-10{sup 3} M{sub Sun} pc{sup -2}), which are much higher than have been observed in dwarf galaxies. This implies either higher values of SFE in these dwarf starburst galaxies or the presence of significant amounts of H{sub 2} in dwarfs (or both). Raising the assumed SFEs to 10% or greater (in line with observations of more massive starbursts associated with merging galaxies), still results in H I surface densities higher than observed in 10 galaxies. Thus, these observations appear to require that a significant fraction of the gas in these dwarf starbursts galaxies was in the molecular form at the onset of the bursts. Our results imply molecular gas column densities in the range 10{sup 19}-10{sup 21} cm{sup -2} for the sample. In the galaxies where CO observations have been made, these densities correspond to values of the CO-H{sub 2} conversion factor (X{sub CO}) in the range >(3-80) Multiplication-Sign 10{sup 20} cm{sup -2} (K km s{sup -1}){sup -1}, or up to 40 Multiplication-Sign greater than Galactic X{sub CO} values.

  18. CONSTRAINTS ON PLANET OCCURRENCE AROUND NEARBY MID-TO-LATE M DWARFS FROM THE MEARTH PROJECT

    SciTech Connect (OSTI)

    Berta, Zachory K.; Irwin, Jonathan; Charbonneau, David, E-mail: zberta@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)

    2013-10-01T23:59:59.000Z

    The MEarth Project is a ground-based photometric survey intended to find planets transiting the closest and smallest main-sequence stars. In its first four years, MEarth discovered one transiting exoplanet, the 2.7 R{sub ?} planet GJ1214b. Here, we answer an outstanding question: in light of the bounty of small planets transiting small stars uncovered by the Kepler mission, should MEarth have found more than just one planet so far? We estimate MEarth's ensemble sensitivity to exoplanets by performing end-to-end simulations of 1.25 × 10{sup 6} observations of 988 nearby mid-to-late M dwarfs, gathered by MEarth between 2008 October and 2012 June. For 2-4 R{sub ?} planets, we compare this sensitivity to results from Kepler and find that MEarth should have found planets at a rate of 0.05-0.36 planets yr{sup –1} in its first four years. As part of this analysis, we provide new analytic fits to the Kepler early M dwarf planet occurrence distribution. When extrapolating between Kepler's early M dwarfs and MEarth's mid-to-late M dwarfs, we find that assuming the planet occurrence distribution stays fixed with respect to planetary equilibrium temperature provides a good match to our detection of a planet with GJ1214b's observed properties. For larger planets, we find that the warm (600-700 K), Neptune-sized (4 R{sub ?}) exoplanets that transit early M dwarfs like Gl436 and GJ3470 occur at a rate of <0.15 star{sup –1} (at 95% confidence) around MEarth's later M dwarf targets. We describe a strategy with which MEarth can increase its expected planet yield by 2.5 × without new telescopes by shifting its sensitivity toward the smaller and cooler exoplanets that Kepler has demonstrated to be abundant.

  19. Vorticity generation in creeping flow past a magnetic obstacle Centro de Investigacin en Energa, UNAM, Apartado Postal 34, Temixco, Morelos 62580, Mexico

    E-Print Network [OSTI]

    Abdou, Mohamed

    Vorticity generation in creeping flow past a magnetic obstacle S. Cuevas* Centro de Investigación Mechanical & Aerospace Engineering Department, UCLA, 44-114 Engineering IV, Los Angeles, California 90095 The generation of vorticity in the two-dimensional creeping flow of an incompressible, electrically conduct- ing

  20. Deformation of Compliant Fault Zones Induced by Nearby Earthquakes: Theoretical Investigations in Three Dimensions and Applications to The East California Shear Zone

    E-Print Network [OSTI]

    Kang, Jingqian

    2014-02-21T23:59:59.000Z

    Using dynamic modeling of earthquake rupture on a strike-slip fault and seismic wave propagation in a three dimensional inhomogeneous elastoplastic medium, I investigate the inelastic response of compliant fault zones to nearby earthquakes. I...

  1. NEAT, An Astrometric Telescope To Probe Planetary Systems Down To The Earth Mass Around Nearby Solar-Type Stars

    E-Print Network [OSTI]

    Malbet, F; Goullioud, R; Shao, M; Lagage, P -O; Cara, C; Durand, G; Feautrier, P; Jakobsson, B; Hinglais, E; Mercier, M

    2011-01-01T23:59:59.000Z

    The NEAT (Nearby Earth Astrometric Telescope) mission is a proposition submitted to ESA for its 2010 call for M-size mission. The main scientific goal is to detect and characterize planetary systems in an exhaustive way down to 1 Earth mass in the habitable zone and further away, around nearby stars for F, G, and K spectral types. This survey would provide the actual planetary masses, the full characterization of the orbits including their inclination, for all the components of the planetary system down to that mass limit. Extremely- high-precision astrometry, in space, can detect the dynamical effect due to even low mass orbiting planets on their central star, reaching those scientific goals. NEAT will continue the work performed by Hipparcos (1mas precision) and Gaia (7{\\mu}as aimed) by reaching a precision that is improved by two orders of magnitude (0.05{\\mu}as, 1{\\sigma} accuracy). The two modules of the payload, the telescope and the focal plane, must be placed 40m away leading to a formation flying opt...

  2. Nepal: Obstacles to Peace

    E-Print Network [OSTI]

    International Crisis Group

    2003-06-17T23:59:59.000Z

    not stand the test of time. By the reckoning of almost all involved, any peace deal will require some form of constitutional amendment, or even the preparation of a new constitution. Without the broad buy-in of society, constitutional revision... . However, five days later, an RNA spokesperson indicated that the military would not restrict its movements until the Maoists returned weapons looted from it during the war.35 This set off confusing and continuing exchanges regarding whether...

  3. CAIRNS: The Cluster And Infall Region Nearby Survey III. Environmental Dependence of H-alpha Properties of Galaxies

    E-Print Network [OSTI]

    Kenneth Rines; Margaret J. Geller; Michael J. Kurtz; Antonaldo Diaferio

    2005-06-27T23:59:59.000Z

    We investigate the environmental dependence of star formation in cluster virial regions and infall regions as part of CAIRNS (Cluster And Infall Region Nearby Survey), a large spectroscopic survey of the infall regions surrounding nine nearby rich clusters of galaxies. Our long-slit spectroscopy yields estimates of star formation rates in environments from cluster cores to the general large-scale structure. The fraction of galaxies with current star formation in their inner disks as traced by H-alpha emission increases with distance from the cluster and converges to the ``field'' value only at 2-3 virial radii, in agreement with other investigations. However, among galaxies with significant current star formation (EW[Ha]geq2\\AA), there is no difference in the distribution of EW[Ha] inside and outside the virial radius. This surprising result, first seen by Carter et al., suggests that (1) star formation is truncated on either very short timescales or only at moderate and high redshifts or (2) that projection effects contaminate the measurement. The number density profiles of star-forming and non-star-forming galaxies indicate that, among galaxies projected inside the virial radius, at least half of the former and 20% of the latter are ``infall interlopers,'' galaxies in the infall region but outside the virial region. The kinematics of star-forming galaxies in the infall region closely match those of absorption-dominated galaxies. This result shows that the star forming galaxies in the infall regions are not interlopers from the field and excludes one model of the backsplash scenario of galaxy transformation. Finally, we quantify systematic uncertainties in estimating the global star formation in galaxies from their inner disks.

  4. HIGH IONIZATION SPECIES IN THE NEARBY INTERSTELLAR MEDIUM FROM AN EXHAUSTIVE ANALYSIS OF THE IUE INES DATABASE

    SciTech Connect (OSTI)

    Freire Ferrero, R.; Halbwachs, J.-L. [Observatoire Astronomique, Universite de Strasbourg, 11 rue de l'Universite, 67.000 Strasbourg (France); Morales Duran, C.; Cabo Cubeiro, A. M., E-mail: rubens.freire@astro.unistra.fr, E-mail: jean-louis.halbwachs@astro.unistra.fr, E-mail: morales@cab.inta-csic.es, E-mail: amcabo@cab.inta-csic.es [LAEX, Centro de Astrobiologia (CAB, CSIC-INTA), LAEFF, European Space Astronomy Centre, P.O. Box 78, 28691 Villanueva de la Canada, Madrid (Spain)

    2012-02-15T23:59:59.000Z

    Main-sequence (MS) and giant late-B and early-A type stars are the best targets for searching for nearby interstellar (IS) Si IV and C IV resonance lines because they are not able to produce them, either in atmospheric layers or in their circumstellar environment, and because many stars of these spectral types are nearby and located in the local interstellar medium (LISM). In addition, the use of certain stars hotter than B6 can lead to misinterpretations (e.g., alpha Arae). This work analyzes the reliable Short-Wavelength Prime high-resolution UV spectra of 558 B6-A9 type stars observed by the International Ultraviolet Explorer at distances lower than 400 pc from the Sun. For the first time, this work utilizes the entire INES database to extract stellar and IS information in a systematic way from homogeneous data. Stars were classified into seven groups: normal (MS and subgiant), giant, peculiar, emission line, Algols, pre-main sequence or Herbig Ae/Be, and shell stars. Only 10 normal stars, located beyond 90 pc, show weak Si IV and C IV absorptions and are clustered around the direction of Sco-Cen, while 85 located closer than 90 pc, as well as another 89 beyond 90 pc, do not show any absorptions at all. We conclude that these highly ionized species originate most probably in the LISM, at 90 pc from the Sun, corresponding to the warm interaction zone (IZ), where the expanding Loop I super-shell and the Local Bubble collide. We base our results on a robust statistical analysis of both spectral types and spatial distributions of the different stellar groups we defined. Our estimated column densities N of both ions are similar to those obtained by other authors for distant stars, suggesting that these absorptions concentrate fundamentally in the IZ. A logarithmic correlation between N and the distance D confirms these results.

  5. Circumnuclear Dust in Nearby Active and Inactive Galaxies. II. Bars, Nuclear Spirals, and the Fueling of Active Galactic Nuclei

    E-Print Network [OSTI]

    Paul Martini; Michael W. Regan; John S. Mulchaey; Richard W. Pogge

    2002-12-17T23:59:59.000Z

    (Abridged) We present a detailed study of the relation between circumnuclear dust morphology, host galaxy properties, and nuclear activity in nearby galaxies. We use our sample of 123 nearby galaxies with visible--near-infrared colormaps from the Hubble Space Telescope to create well-matched, "paired" samples of 28 active and 28 inactive galaxies, as well as 19 barred and 19 unbarred galaxies, that have the same host galaxy properties. Comparison of the barred and unbarred galaxies shows that grand design nuclear dust spirals are only found in galaxies with a large-scale bar. Tightly wound nuclear dust spirals, in contrast, show a strong tendency to avoid galaxies with large-scale bars. Comparison of the AGN and inactive samples shows that nuclear dust spirals, which may trace shocks and angular momentum dissipation in the ISM, occur with comparable frequency in both active and inactive galaxies. The only difference between the active and inactive galaxies is that several inactive galaxies appear to completely lack dust structure in their circumnuclear region, while none of the AGN lack this structure. The comparable frequency of nuclear spirals in active and inactive galaxies, combined with previous work that finds no significant differences in the frequency of bars or interactions between well-matched active and inactive galaxies, suggests that no universal fueling mechanism for low-luminosity AGN operates at spatial scales greater than ~100 pc radius from the galactic nuclei. The similarities instead suggest that the lifetime of nuclear activity is less than the characteristic inflow time from these spatial scales. An order-of-magnitude estimate of this inflow time is the dynamical timescale. This sets an upper limit of several million years to the lifetime of an individual episode of nuclear activity.

  6. Theorizing the carbon economy: introduction to the special issue The term `carbon economy'often has an adjective placed nearby: the `new'carbon economy,

    E-Print Network [OSTI]

    of carbon capture and storage and nuclear technologies. These dimensionsöand surface-level to deeperTheorizing the carbon economy: introduction to the special issue The term `carbon economy'often has an adjective placed nearby: the `new'carbon economy, the `low' carbon economy, the carbon `neutral' economy

  7. THE ADVANCED CAMERA FOR SURVEYS NEARBY GALAXY SURVEY TREASURY. VI. THE ANCIENT STAR-FORMING DISK OF NGC 404

    SciTech Connect (OSTI)

    Williams, Benjamin F.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Stilp, Adrienne [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Dolphin, Andrew [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85706 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Weisz, Daniel; Skillman, Evan, E-mail: ben@astro.washington.ed, E-mail: jd@astro.washington.ed, E-mail: stephanie@astro.washington.ed, E-mail: roskar@astro.washington.ed, E-mail: dolphin@raytheon.co, E-mail: aseth@cfa.harvard.ed, E-mail: dweisz@astro.umn.ed, E-mail: skillman@astro.umn.ed [Department of Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States)

    2010-06-10T23:59:59.000Z

    We present HST/WFPC2 observations across the disk of the nearby isolated dwarf S0 galaxy NGC 404, which hosts an extended gas disk. The locations of our fields contain a roughly equal mixture of bulge and disk stars. All of our resolved stellar photometry reaches m {sub F814W} = 26 (M {sub F814W} = -1.4), which covers 2.5 mag of the red giant branch and main-sequence stars with ages <300 Myr. Our deepest field reaches m {sub F814W} = 27.2 (M {sub F814W} = -0.2), sufficient to resolve the red clump and main-sequence stars with ages <500 Myr. Although we detect trace amounts of star formation at times more recent than 10 Gyr ago for all fields, the proportion of red giant stars to asymptotic giants and main-sequence stars suggests that the disk is dominated by an ancient (>10 Gyr) population. Detailed modeling of the color-magnitude diagram suggests that {approx}70% of the stellar mass in the NGC 404 disk formed by z {approx} 2 (10 Gyr ago) and at least {approx}90% formed prior to z {approx} 1 (8 Gyr ago). These results indicate that the stellar populations of the NGC 404 disk are on average significantly older than those of other nearby disk galaxies, suggesting that early- and late-type disks may have different long-term evolutionary histories, not simply differences in their recent star formation rates. Comparisons of the spatial distribution of the young stellar mass and FUV emission in Galaxy Evolution Explorer images show that the brightest FUV regions contain the youngest stars, but that some young stars (<160 Myr) lie outside of these regions. FUV luminosity appears to be strongly affected by both age and stellar mass within individual regions. Finally, we use our measurements to infer the relationship between the star formation rate and the gas density of the disk at previous epochs. We find that most of the history of the NGC 404 disk is consistent with star formation that has decreased with the gas density according to the Schmidt law. However, {approx} 0.5-1 Gyr ago, the star formation rate was unusually low for the inferred gas density, consistent with the possibility that there was a gas accretion event that reignited star formation {approx}0.5 Gyr ago. Such an event could explain why this S0 galaxy hosts an extended gas disk.

  8. The Heating of Mid-Infrared Dust in the Nearby Galaxy M33: A Testbed for Tracing Galaxy Evolution

    E-Print Network [OSTI]

    Calapa, M; Draine, B T; Boquien, M; Kramer, C; Xilouris, M; Verley, S; Braine, J; Relaño-Pastor, M; van der Werf, P; Israel, F; Hermelo, I; Albrecht, M

    2014-01-01T23:59:59.000Z

    Because the 8 {\\mu}m polycyclic aromatic hydrocarbon (PAH) emission has been found to correlate with other well-known star formation tracers, it has widely been used as a star formation rate (SFR) tracer. There are, however, studies that challenge the accuracy and reliability of the 8 {\\mu}m emission as a SFR tracer. Our study, part of the Herschel M33 Extended Survey (HERM33ES) open time key program, aims at addressing this issue by analyzing the infrared emission from the nearby spiral galaxy M33 at the high spatial scale of 75 pc. Combining data from the Herschel Space Observatory and the Spitzer Space Telescope we find that the 8 {\\mu}m emission is better correlated with the 250 {\\mu}m emission, which traces cold interstellar gas, than with the 24 {\\mu}m emission. The L(8)/L(24) ratio is highly depressed in 24 {\\mu}m luminous regions, which correlate with known HII regions. We also compare our results with the dust emission models by Draine & Li (2007). We confirm that the depression of 8 {\\mu}m PAH e...

  9. BANYAN. VII. A New Population of Young Substellar Candidate Members of Nearby Moving Groups from the BASS Survey

    E-Print Network [OSTI]

    Gagné, Jonathan; Cruz, Kelle L; Lafrenière, David; Doyon, René; Malo, Lison; Burgasser, Adam J; Naud, Marie-Eve; Artigau, Étienne; Bouchard, Sandie; Gizis, John E; Albert, Loïc

    2015-01-01T23:59:59.000Z

    [Abbreviated] We present the results of a near-infrared (NIR) spectroscopic follow-up survey of 182 M4-L7 low-mass stars and brown dwarfs (BDs) from the BANYAN All-Sky Survey (BASS) for candidate members of nearby, young moving groups (YMGs). We confirm signs of low-gravity for 42 new BD discoveries with estimated masses between 8-75 $M_{Jup}$ and identify previously unrecognized signs of low gravity for 24 known BDs. This allows us to refine the fraction of low-gravity dwarfs in the high-probability BASS sample to $\\sim$82%. We use this unique sample of 66 young BDs, supplemented with 22 young BDs from the literature, to construct new empirical NIR absolute magnitude and color sequences for low-gravity BDs. We obtain a spectroscopic confirmation of low-gravity for 2MASS J14252798-3650229, which is a new $\\sim$27 $M_{Jup}$, L4 $\\gamma$ bona fide member of AB Doradus. We identify a total of 19 new low-gravity candidate members of YMGs with estimated masses below 13 $M_{Jup}$, seven of which have kinematically ...

  10. The Solar Neighborhood XXXVI: The Long-Term Photometric Variability of Nearby Red Dwarfs in the VRI Optical Bands

    E-Print Network [OSTI]

    Hosey, Altonio D; Jao, Wei-Chun; Dieterich, Sergio B; Winters, Jennifer G; Lurie, John C; Riedel, Adric R; Subasavage, John P

    2015-01-01T23:59:59.000Z

    We present an analysis of long-term photometric variability for nearby red dwarfs at optical wavelengths. The sample consists of 264 M dwarfs south of DEC = +30 with V-K = 3.96-9.16 and Mv~10-20 (spectral types M2V-M8V), most of which are within 25 pc. The stars have been observed in the VRI filters for ~4-14 years at the CTIO/SMARTS 0.9m telescope. Of the 238 red dwarfs within 25 pc, we find that only ~8% are photometrically variable by at least 20 mmag (~2%) in the VRI bands. We find that high variability at optical wavelengths over the long-term can be used to identify young stars. Overall, however, the fluxes of most red dwarfs at optical wavelengths are steady to a few percent over the long term. The low overall rate of photometric variability for red dwarfs is consistent with results found in previous work on similar stars on shorter timescales, with the body of work indicating that most red dwarfs are only mildly variable. We highlight 17 stars that show long-term changes in brightness, sometimes becau...

  11. Acceleration of Solar Wind Ions by Nearby Interplanetary Shocks: Comparison of Monte Carlo Simulations with Ulysses Observations

    E-Print Network [OSTI]

    Matthew G. Baring; Keith Ogilvie; Donald Ellison; Robert Forsyth

    1996-10-02T23:59:59.000Z

    The most stringent test of theoretical models of the first-order Fermi mechanism at collisionless astrophysical shocks is a comparison of the theoretical predictions with observational data on particle populations. Such comparisons have yielded good agreement between observations at the quasi-parallel portion of the Earth's bow shock and three theoretical approaches, including Monte Carlo kinetic simulations. This paper extends such model testing to the realm of oblique interplanetary shocks: here observations of proton and alpha particle distributions made by the SWICS ion mass spectrometer on Ulysses at nearby interplanetary shocks are compared with test particle Monte Carlo simulation predictions of accelerated populations. The plasma parameters used in the simulation are obtained from measurements of solar wind particles and the magnetic field upstream of individual shocks. Good agreement between downstream spectral measurements and the simulation predictions are obtained for two shocks by allowing the the ratio of the mean-free scattering length to the ionic gyroradius, to vary in an optimization of the fit to the data. Generally small values of this ratio are obtained, corresponding to the case of strong scattering. The acceleration process appears to be roughly independent of the mass or charge of the species.

  12. XRF 100316D/SN 2010bh: clue to the diverse origin of nearby supernova-associated GRBs

    E-Print Network [OSTI]

    Fan, Yi-Zhong; Xu, Dong; Liang, En-Wei; Zhang, Bing

    2010-01-01T23:59:59.000Z

    X-ray Flash (XRF) 100316D, a nearby super-long under-luminous burst with a peak energy E_p \\sim 20 keV, was detected by Swift and was found to be associated with an energetic supernova SN 2010bh. Both the spectral and the temporal behavior of this burst are rather similar to that of XRF 060218, except that the latter was associated with a "less energetic" SN 2006aj and had a prominent soft thermal emission component in the spectrum. We analyze the spectral and temporal properties of this burst, and interpret the prompt gamma-ray emission and the early X-ray plateau emission as synchrotron emission from a dissipating Poynting-flux-dominated outflow, probably powered by a magnetar with a spin period of $P \\sim 10$ ms and the polar cap magnetic field $B_{\\rm p} \\sim 3\\times 10^{15}$ G. The energetic supernova SN 2010bh associated with this burst is, however, difficult to interpret within the slow magnetar model, which implies that the nascent magnetar may spin much faster with an initial rotation period $\\sim 1$...

  13. Trumpeting M Dwarfs with CONCH-SHELL: a Catalog of Nearby Cool Host-Stars for Habitable ExopLanets and Life

    E-Print Network [OSTI]

    Gaidos, E; Lepine, S; Buccino, A; James, D; Ansdell, M; Petrucci, R; Mauas, P; Hilton, E J

    2014-01-01T23:59:59.000Z

    We present an all-sky catalog of 2970 nearby ($d \\lesssim 50$ pc), bright ($JDoppler radial velocity surveys. Stars were selected from the SUPERBLINK proper motion catalog according to absolute magnitudes, spectra, or a combination of reduced proper motions and photometric colors. From our spectra we determined gravity-sensitive indices, and identified and removed 0.2% of these as interloping hotter or evolved stars. Thirteen percent of the stars exhibit H-alpha emission, an indication of stellar magnetic activity and possible youth. The mean metallicity is [Fe/H] = -0.07 with a standard deviation of 0.22 dex, similar to nearby solar-type stars. We determined stellar effective temperatures by least-squares fitting of spectra to model predictions calibrated by fits to sta...

  14. Four nearby L dwarfs

    E-Print Network [OSTI]

    I. Neill Reid; J. Davy Kirkpatrick; J. E. Gizis; C. C. Dahn; D. G. Monet; R. J. Williams; James Liebert; A. J. Burgasser

    1999-09-20T23:59:59.000Z

    We present spectroscopic, photometric and astrometric observations of four bright L dwarfs identified in the course of the 2MASS near-infrared survey. Our spectroscopic data extend to wavelengths shortward of 5000\\AA in the L0 dwarf 2MASSJ0746+2000 and the L4 dwarf 2MASSJ0036+1840, allowing the identification of absorption bands due to MgH and CaOH. The atomic resonance lines Ca I 4227\\AA and Na I 5890/5896\\AA are extremely strong, with the latter having an equivalent width of 240\\AA in the L4 dwarf. By spectral type L5, the D lines extend over $\\sim1000$\\AA and absorb a substantial fraction of the flux emitted in the V band, with a corresponding effect on the (V-I) broadband colour. The KI resonance doublet at 7665/7699\\AA increases in equivalent width from spectral type M3 to M7, but decreases in strength from M7 to L0 before broadening substantially at later types. These variations are likely driven by dust formation in these cool atmospheres.

  15. The nearby supernova factory

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    cadence gives fewer supernovae but better constraints on thein 2003. Key words: supernovae, galaxies Preprint submitted2004 Introduction Type Ia supernovae (SNe Ia) have proven

  16. Far-Ultraviolet Spectroscopy of Star-Forming Regions in Nearby Galaxies: Stellar Populations and Abundance Indicators

    E-Print Network [OSTI]

    William C. Keel; Jay B. Holberg; Patrick M. Treuthardt

    2004-03-20T23:59:59.000Z

    We present FUSE spectroscopy and supporting data for star-forming regions in nearby galaxies, to examine their massive-star content and explore the use of abundance and population indicators in this spectral range for high-redshift galaxies. New far-ultraviolet spectra are shown for four bright H II regions in M33 (NGC 588, 592, 595, and 604), the H II region NGC 5461 in M101, and the starburst nucleus of NGC 7714, supplemented by the very-low-metallicity galaxy I Zw 18. In each case, we see strong Milky Way absorption systems from H2, but intrinsic absorption within each galaxy is weak or undetectable, perhaps because of the "UV bias" in which reddened stars which lie behind molecular-rich areas are also heavily reddened. We see striking changes in the stellar-wind lines from these populations with metallicity, suggesting that C II, C III, C IV, N II, N III, and P V lines are potential tracers of stellar metallicity in star-forming galaxies. Three of these relations - involving N IV, C III, and P V - are nearly linear over the range from O/H=0.05--0.8 solar. The major difference in continuum shapes among these systems is that the giant H II complex NGC 604 has a stronger continuum shortward of 950 A than any other object in this sample. Small-number statistics would likely go in the other direction; we favor this as the result of a discrete star-forming event ~3 Myr ago, as suggested by previous studies of its stellar population. (Supported by NASA grant NAG5-8959)

  17. THE Pa{alpha} LUMINOSITY FUNCTION OF H II REGIONS IN NEARBY GALAXIES FROM HST/NICMOS

    SciTech Connect (OSTI)

    Liu Guilin; Calzetti, Daniela [Astronomy Department, University of Massachusetts, Amherst, MA 01003 (United States); Kennicutt, Robert C. Jr. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Schinnerer, Eva [MPI for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Sofue, Yoshiaki [Department of Physics, Meisei University, 2-1-1 Hodokubo, Hino, Tokyo 191-8506 (Japan); Komugi, Shinya [Joint ALMA Office, Alonso de Cordova 3107, Vitacura, Santiago 763-0355 (Chile); Egusa, Fumi [Institute of Space and Aeronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshino-dai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Scoville, Nicholas Z., E-mail: liu@pha.jhu.edu [California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States)

    2013-07-20T23:59:59.000Z

    The H II region luminosity function (LF) is an important tool for deriving the birthrates and mass distribution of OB associations and is an excellent tracer of the newly formed massive stars and associations. To date, extensive work (predominantly in H{alpha}) has been done from the ground, which is hindered by dust extinction and the severe blending of adjacent (spatially or in projection) H II regions. Reliably measuring the properties of H II regions requires a linear resolution <40 pc, but analyses satisfying this requirement have been done only in a handful of galaxies, so far. As the first space-based work using a galaxy sample, we have selected 12 galaxies from our HST/NICMOS Pa{alpha} survey and studied the LF and size distribution of H II regions both in individual galaxies and cumulatively, using a virtually extinction-free tracer of the ionizing photon rate. The high angular resolution and low sensitivity to diffuse emission of NICMOS also offer an advantage over ground-based imaging by enabling a higher degree of de-blending of the H II regions. We do not confirm the broken power-law LFs found in ground-based studies. Instead, we find that the LFs, both individual and co-added, follow a single power law dN(L)/dln L{proportional_to}L {sup -1}, are consistent with the mass function of star clusters in nearby galaxies, and are in agreement with the results of the existing analyses with Hubble Space Telescope (HST) data. The individual and co-added size distributions of H II regions are both roughly consistent with dN(D)/dln D{proportional_to}D {sup -3}, but the power-law scaling is probably contaminated by blended regions or complexes.

  18. OXYGEN ABUNDANCES IN NEARBY FGK STARS AND THE GALACTIC CHEMICAL EVOLUTION OF THE LOCAL DISK AND HALO

    SciTech Connect (OSTI)

    Ramirez, I.; Lambert, D. L. [McDonald Observatory and Department of Astronomy, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States)] [McDonald Observatory and Department of Astronomy, University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States); Allende Prieto, C. [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain)] [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2013-02-10T23:59:59.000Z

    Atmospheric parameters and oxygen abundances of 825 nearby FGK stars are derived using high-quality spectra and a non-local thermodynamic equilibrium analysis of the 777 nm O I triplet lines. We assign a kinematic probability for the stars to be thin-disk (P {sub 1}), thick-disk (P {sub 2}), and halo (P {sub 3}) members. We confirm previous findings of enhanced [O/Fe] in thick-disk (P {sub 2} > 0.5) relative to thin-disk (P {sub 1} > 0.5) stars with [Fe/H] {approx}< -0.2, as well as a 'knee' that connects the mean [O/Fe]-[Fe/H] trend of thick-disk stars with that of thin-disk members at [Fe/H] {approx}> -0.2. Nevertheless, we find that the kinematic membership criterion fails at separating perfectly the stars in the [O/Fe]-[Fe/H] plane, even when a very restrictive kinematic separation is employed. Stars with 'intermediate' kinematics (P {sub 1} < 0.7, P {sub 2} < 0.7) do not all populate the region of the [O/Fe]-[Fe/H] plane intermediate between the mean thin-disk and thick-disk trends, but their distribution is not necessarily bimodal. Halo stars (P {sub 3} > 0.5) show a large star-to-star scatter in [O/Fe]-[Fe/H], but most of it is due to stars with Galactocentric rotational velocity V < -200 km s{sup -1}; halo stars with V > -200 km s{sup -1} follow an [O/Fe]-[Fe/H] relation with almost no star-to-star scatter. Early mergers with satellite galaxies explain most of our observations, but the significant fraction of disk stars with 'ambiguous' kinematics and abundances suggests that scattering by molecular clouds and radial migration have both played an important role in determining the kinematic and chemical properties of solar neighborhood stars.

  19. THE ACS NEARBY GALAXY SURVEY TREASURY. IX. CONSTRAINING ASYMPTOTIC GIANT BRANCH EVOLUTION WITH OLD METAL-POOR GALAXIES

    SciTech Connect (OSTI)

    Girardi, Leo [Osservatorio Astronomico di Padova-INAF, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Williams, Benjamin F.; Gilbert, Karoline M.; Rosenfield, Philip; Dalcanton, Julianne J. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Marigo, Paola [Dipartimento di Astronomia, Universita di Padova, Vicolo dell'Osservatorio 2, I-35122 Padova (Italy); Boyer, Martha L. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Dolphin, Andrew [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Weisz, Daniel R.; Skillman, Evan [Department of Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Melbourne, Jason [Caltech Optical Observatories, Division of Physics, Mathematics and Astronomy, Mail Stop 301-17, California Institute of Technology, Pasadena, CA 91125 (United States); Olsen, Knut A. G. [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2010-12-01T23:59:59.000Z

    In an attempt to constrain evolutionary models of the asymptotic giant branch (AGB) phase at the limit of low masses and low metallicities, we have examined the luminosity functions and number ratios between AGB and red giant branch (RGB) stars from a sample of resolved galaxies from the ACS Nearby Galaxy Survey Treasury. This database provides Hubble Space Telescope optical photometry together with maps of completeness, photometric errors, and star formation histories for dozens of galaxies within 4 Mpc. We select 12 galaxies characterized by predominantly metal-poor populations as indicated by a very steep and blue RGB, and which do not present any indication of recent star formation in their color-magnitude diagrams. Thousands of AGB stars brighter than the tip of the RGB (TRGB) are present in the sample (between 60 and 400 per galaxy), hence, the Poisson noise has little impact in our measurements of the AGB/RGB ratio. We model the photometric data with a few sets of thermally pulsing AGB (TP-AGB) evolutionary models with different prescriptions for the mass loss. This technique allows us to set stringent constraints on the TP-AGB models of low-mass, metal-poor stars (with M < 1.5 M{sub sun}, [Fe/H]{approx}< -1.0). Indeed, those which satisfactorily reproduce the observed AGB/RGB ratios have TP-AGB lifetimes between 1.2 and 1.8 Myr, and finish their nuclear burning lives with masses between 0.51 and 0.55 M{sub sun}. This is also in good agreement with recent observations of white dwarf masses in the M4 old globular cluster. These constraints can be added to those already derived from Magellanic Cloud star clusters as important mileposts in the arduous process of calibrating AGB evolutionary models.

  20. THE ADVANCED CAMERA FOR SURVEYS NEARBY GALAXY SURVEY TREASURY. V. RADIAL STAR FORMATION HISTORY OF NGC 300

    SciTech Connect (OSTI)

    Gogarten, Stephanie M.; Dalcanton, Julianne J.; Williams, Benjamin F.; Roskar, Rok; Gilbert, Karoline M.; Quinn, Thomas R. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Holtzman, Jon [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger Street, Las Cruces, NM 88003 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Dolphin, Andrew [Raytheon Company, 1151 East Hermans Road, Tucson, AZ 85756 (United States); Weisz, Daniel; Skillman, Evan [Department of Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Cole, Andrew [School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania (Australia); Debattista, Victor P. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Olsen, Knut [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); De Jong, Roelof S. [Astrophysikalisches Institut Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam (Germany); Karachentsev, Igor D., E-mail: stephanie@astro.washington.ed [Special Astrophysical Observatory, Nizhnij Arkhyz, KChR (Russian Federation)

    2010-04-01T23:59:59.000Z

    We present new Hubble Space Telescope (HST) observations of NGC 300 taken as part of the Advanced Camera for Surveys Nearby Galaxy Survey Treasury (ANGST). Individual stars are resolved in these images down to an absolute magnitude of M{sub F814W} = 1.0 (below the red clump). We determine the star formation history of the galaxy in six radial bins by comparing our observed color-magnitude diagrams (CMDs) with synthetic CMDs based on theoretical isochrones. We find that the stellar disk out to 5.4 kpc is primarily old, in contrast with the outwardly similar galaxy M33. We determine the scale length as a function of age and find evidence for inside-out growth of the stellar disk: the scale length has increased from 1.1 +- 0.1 kpc 10 Gyr ago to 1.3 +- 0.1 kpc at present, indicating a buildup in the fraction of young stars at larger radii. As the scale length of M33 has recently been shown to have increased much more dramatically with time, our results demonstrate that two galaxies with similar sizes and morphologies can have very different histories. With an N-body simulation of a galaxy designed to be similar to NGC 300, we determine that the effects of radial migration should be minimal. We trace the metallicity gradient as a function of time and find a present-day metallicity gradient consistent with that seen in previous studies. Consistent results are obtained from archival images covering the same radial extent but differing in placement and filter combination.

  1. THE ADVANCED CAMERA FOR SURVEYS NEARBY GALAXY SURVEY TREASURY. IV. THE STAR FORMATION HISTORY OF NGC 2976

    SciTech Connect (OSTI)

    Williams, Benjamin F.; Dalcanton, Julianne J.; Stilp, Adrienne; Gilbert, Karoline M.; Roskar, Rok; Gogarten, Stephanie M. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Seth, Anil C. [CfA Fellow, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Weisz, Daniel; Skillman, Evan [Department of Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85706 (United States); Holtzman, Jon, E-mail: ben@astro.washington.ed, E-mail: jd@astro.washington.ed, E-mail: roskar@astro.washington.ed, E-mail: stephanie@astro.washington.ed, E-mail: aseth@cfa.harvard.ed, E-mail: dweisz@astro.umn.ed, E-mail: skillman@astro.umn.ed, E-mail: dolphin@raytheon.co, E-mail: holtz@nmsu.ed [Department of Astronomy, New Mexico State University, Box 30001, 1320 Frenger St., Las Cruces, NM 88003 (United States)

    2010-01-20T23:59:59.000Z

    We present resolved stellar photometry of NGC 2976 obtained with the Advanced Camera for Surveys (ACS) as part of the ACS Nearby Galaxy Survey Treasury (ANGST) program. The data cover the radial extent of the major axis of the disk out to 6 kpc, or approx6 scale lengths. The outer disk was imaged to a depth of M{sub F606W} approx 1, and an inner field was imaged to the crowding limit at a depth of M{sub F606W} approx -1. Through detailed analysis and modeling of the resulting color-magnitude diagrams, we have reconstructed the star formation history (SFH) of the stellar populations currently residing in these portions of the galaxy, finding similar ancient populations at all radii but significantly different young populations at increasing radii. In particular, outside of the well-measured break in the disk surface brightness profile, the age of the youngest population increases with distance from the galaxy center, suggesting that star formation is shutting down from the outside-in. We use our measured SFH, along with H I surface density measurements, to reconstruct the surface density profile of the disk during previous epochs. Comparisons between the recovered star formation rates and reconstructed gas densities at previous epochs are consistent with star formation following the Schmidt law during the past 0.5 Gyr, but with a drop in star formation efficiency at low gas densities, as seen in local galaxies at the present day. The current rate and gas density suggest that rapid star formation in NGC 2976 is currently in the process of ceasing from the outside-in due to gas depletion. This process of outer disk gas depletion and inner disk star formation was likely triggered by an interaction with the core of the M81 group approx>1 Gyr ago that stripped the gas from the galaxy halo and/or triggered gas inflow from the outer disk toward the galaxy center.

  2. Pushmataha Forest Habitat Research Area TALL TIMBERS

    E-Print Network [OSTI]

    Balasundaram, Balabhaskar "Baski"

    . Determine the effects of fire and fire frequency on post oak and blackjack oak acorn production, crown vigor monitored other than through pellet count data on the FHRA. Plots were laid out and fire guards bladed

  3. PACS photometry of the Herschel Reference Survey - Far-infrared/sub-millimeter colours as tracers of dust properties in nearby galaxies

    E-Print Network [OSTI]

    Cortese, L; Bianchi, S; Boselli, A; Ciesla, L; Bendo, G J; Boquien, M; Roussel, H; Baes, M; Buat, V; Clemens, M; Cooray, A; Cormier, D; Davies, J I; De Looze, I; Eales, S A; Fuller, C; Hunt, L K; Madden, S; Munoz-Mateos, J; Pappalardo, C; Pierini, D; Remy-Ruyer, A; Sauvage, M; Alighieri, S di Serego; Smith, M W L; Spinoglio, L; Vaccari, M; Vlahakis, C

    2014-01-01T23:59:59.000Z

    We present Herschel/PACS 100 and 160 micron integrated photometry for the 323 galaxies in the Herschel Reference Survey (HRS), a K-band-, volume-limited sample of galaxies in the local Universe. Once combined with the Herschel/SPIRE observations already available, these data make the HRS the largest representative sample of nearby galaxies with homogeneous coverage across the 100-500 micron wavelength range. In this paper, we take advantage of this unique dataset to investigate the properties and shape of the far-infrared/sub-millimeter spectral energy distribution in nearby galaxies. We show that, in the stellar mass range covered by the HRS (8

  4. New Perspectives on the X-ray Emission of HD 104237 and Other Nearby Herbig Ae/Be Stars from XMM-Newton and Chandra

    E-Print Network [OSTI]

    S. Skinner; M. Guedel; M. Audard; K. Smith

    2004-05-23T23:59:59.000Z

    We present new X-ray observations of the nearby Herbig Ae star HD 104237 (= DX Cha) with XMM-Newton, whose objective is to clarify the origin of the emission. Several X-ray emission lines are clearly visible in the CCD spectra, including the high-temperature Fe K-alpha complex. The emission can be accurately modeled as a multi-temperature thermal plasma with cool (kT 3 keV) components. The presence of a hot component is compelling evidence that the X-rays originate in magnetically confined plasma, either in the Herbig star itself or in the corona of an as yet unseen late-type companion. The X-ray temperatures and luminosity (log Lx = 30.5 ergs/s) are within the range expected for a T Tauri companion, but high resolution Chandra and HST images constrain the separation of a putative companion to less than 1 arcsec. We place these new results into broader context by comparing the X-ray and bolometric luminosities of a sample of nearby Herbig stars with those of T Tauri stars and classical main-sequence Be stars. We also test the predictions of a model that attributes the X-ray emission of Herbig stars to magnetic activity that is sustained by a shear-powered dynamo.

  5. CARMA SURVEY TOWARD INFRARED-BRIGHT NEARBY GALAXIES (STING). III. THE DEPENDENCE OF ATOMIC AND MOLECULAR GAS SURFACE DENSITIES ON GALAXY PROPERTIES

    SciTech Connect (OSTI)

    Wong, Tony; Xue, Rui [Department of Astronomy, University of Illinois, Urbana, IL 61801 (United States)] [Department of Astronomy, University of Illinois, Urbana, IL 61801 (United States); Bolatto, Alberto D.; Fisher, David B.; Vogel, Stuart N. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)] [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Leroy, Adam K. [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States)] [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Blitz, Leo [Department of Astronomy, University of California, Berkeley, CA 94720 (United States)] [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Rosolowsky, Erik [Department of Physics, University of Alberta, Edmonton, AB T6G 2E1 (Canada)] [Department of Physics, University of Alberta, Edmonton, AB T6G 2E1 (Canada); Bigiel, Frank [Institut für theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle Str. 2, D-69120 Heidelberg (Germany)] [Institut für theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle Str. 2, D-69120 Heidelberg (Germany); Ott, Jürgen [National Radio Astronomy Observatory, Socorro, NM 87801 (United States)] [National Radio Astronomy Observatory, Socorro, NM 87801 (United States); Rahman, Nurur [Department of Physics, C1 Lab 140, University of Johannesburg, P.O. Box 524, Auckland Park, Johannesburg 2006 (South Africa)] [Department of Physics, C1 Lab 140, University of Johannesburg, P.O. Box 524, Auckland Park, Johannesburg 2006 (South Africa); Walter, Fabian [Max-Planck-Institut für Astronomie, Konigstuhl 17, D-69117 Heidelberg (Germany)] [Max-Planck-Institut für Astronomie, Konigstuhl 17, D-69117 Heidelberg (Germany)

    2013-11-01T23:59:59.000Z

    We investigate the correlation between CO and H I emission in 18 nearby galaxies from the CARMA Survey Toward IR-Bright Nearby Galaxies (STING) at sub-kpc and kpc scales. Our sample, spanning a wide range in stellar mass and metallicity, reveals evidence for a metallicity dependence of the H I column density measured in regions exhibiting CO emission. Such a dependence is predicted by the equilibrium model of McKee and Krumholz, which balances H{sub 2} formation and dissociation. The observed H I column density is often smaller than predicted by the model, an effect we attribute to unresolved clumping, although values close to the model prediction are also seen. We do not observe H I column densities much larger than predicted, as might be expected were there a diffuse H I component that did not contribute to H{sub 2} shielding. We also find that the H{sub 2} column density inferred from CO correlates strongly with the stellar surface density, suggesting that the local supply of molecular gas is tightly regulated by the stellar disk.

  6. The interaction between radio lobes and hot gas in the nearby radio galaxies 3C285 and 3C442A

    E-Print Network [OSTI]

    M. J. Hardcastle; R. P. Kraft; D. M. Worrall; J. H. Croston; D. A. Evans; M. Birkinshaw; S. S. Murray

    2007-03-05T23:59:59.000Z

    We present Chandra observations of two nearby radio galaxies in group environments, 3C285 and 3C442A. The host galaxies of both sources are involved in mergers with nearby massive galaxies, and the hot gas in the systems is extended along lines joining the interacting galaxies. Both sources show strong evidence for interactions between the radio lobes and the asymmetrical hot gas. We argue that the structure in the hot gas is independent of the existence of the radio lobes in these systems, and argue that hot gas shaped by an ongoing massive galaxy merger may play an important role in the dynamics of radio lobes in other objects. For 3C442A, our observations show that gas is being driven out of both members of the host interacting galaxy pair, and the implied constraints on galaxy velocities are consistent with mildly supersonic motions with respect to the group-scale hot gas. The previously known filamentary radio structure in the center of 3C442A may be a result of the interaction between hot gas expelled from these galaxies and pre-existing radio-emitting plasma. In 3C285, where there is no ongoing galaxy merger, the powerful radio source is probably having a significant effect on the energetics of the host group.

  7. Influence of the Fin on Two-Dimensional Characteristics of Dispersed Flow With Wall Liquid Film in the Vicinity of Obstacle

    SciTech Connect (OSTI)

    Stosic, Zoran V. [Framatome ANP GmbH, P.O. Box 3220, 91050 Erlangen (Germany); Stevanovic, Vladimir D. [University of Belgrade, Kraljice Marije 16, 11000 Belgrade, Serbia and Montenegro (Yugoslavia); Serizawa, Akimi [Kyoto University, Kumatori, Sennan, Osaka 590-0494 (Japan)

    2002-07-01T23:59:59.000Z

    Spacers have positive effects on the heat transfer enhancement and critical heat flux (CHF) increase downstream of their location in the boiling channel. These effects are further increased by the inclusion of the fin on the spacer rear edge. Numerical simulation of a separation in a high void gas phase and dispersed droplets flow around a spacer, with a liquid film flowing on the wall, is performed. Mechanisms leading to the CHF increase due to the two-phase flow separation and liquid film thickening downstream the spacer are demonstrated. Numerical simulations of gas phase, entrained droplets and wall liquid film flows were performed with the three-fluid model and with the application of the high order numerical scheme for the liquid film surface interface tracking. Predicted is a separation of gas and entrained droplets streams around the spacer without and with a fin inclined 30 and 60 degrees to the wall, as well as a change of wall liquid film thickness in the vicinity of spacer. Results of liquid film dynamic behaviour are compared with the recently obtained experimental results. Multi-dimensional characteristics of surface waves on the liquid film were measured with newly developed ultrasonic transmission technique in a 3 3 rod bundle test section with air-water flow under atmospheric conditions. Obtained numerical results are in good agreement with experimental observations. The presented investigation gives insight into the complex mechanisms of separated two-phase flow with wall liquid film around the spacer and support thermal-hydraulic design and optimisation of flow obstacles in various thermal equipment. (authors)

  8. Vision-based obstacle avoidance

    DOE Patents [OSTI]

    Galbraith, John (Los Alamos, NM)

    2006-07-18T23:59:59.000Z

    A method for allowing a robot to avoid objects along a programmed path: first, a field of view for an electronic imager of the robot is established along a path where the electronic imager obtains the object location information within the field of view; second, a population coded control signal is then derived from the object location information and is transmitted to the robot; finally, the robot then responds to the control signal and avoids the detected object.

  9. The nearby universe observed in far-infrared and in ultraviolet: an analysis of the dust attenuation and the star formation activity

    E-Print Network [OSTI]

    V. Buat

    2004-11-23T23:59:59.000Z

    We discuss the dust attenuation and the star formation rates in the nearby universe obtained from a comparison of far-infrared (IRAS) and ultraviolet (GALEX) observations. The ratio of the dust to UV flux ratio is used to derive the dust attenuation: this dust attenuation is found to increase with the luminosity of the galaxies and from z=0 to z=1. The slope of the UV continuum is found to be a very poor tracer of the dust attenuation in "normal" galaxies. Galaxies selected by their UV emission are found to be rather quiescent with a recent star formation rate equal to only 25-30% of the past averaged one. Galaxies selected in FIR appear slightly more active in star formation.

  10. Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I

    E-Print Network [OSTI]

    R. O. Gray; C. J. Corbally; R. F. Garrison; M. T. McFadden; P. E. Robinson

    2003-08-11T23:59:59.000Z

    We have embarked on a project, under the aegis of the Nearby Stars (NStars)/ Space Interferometry Mission Preparatory Science Program to obtain spectra, spectral types, and, where feasible, basic physical parameters for the 3600 dwarf and giant stars earlier than M0 within 40 parsecs of the sun. In this paper we report on the results of this project for the first 664 stars in the northern hemisphere. These results include precise, homogeneous spectral types, basic physical parameters (including the effective temperature, surface gravity and the overall metallicity, [M/H]) and measures of the chromospheric activity of our program stars. Observed and derived data presented in this paper are also available on the project's website at http://stellar.phys.appstate.edu/ .

  11. THE ACS NEARBY GALAXY SURVEY TREASURY. VII. THE NGC 4214 STARBURST AND THE EFFECTS OF STAR FORMATION HISTORY ON DWARF MORPHOLOGY

    SciTech Connect (OSTI)

    Williams, Benjamin F.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Weisz, Daniel R. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Seth, Anil C. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Skillman, Evan D. [Department of Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Dolphin, Andrew E., E-mail: ben@astro.washington.edu, E-mail: jd@astro.washington.edu, E-mail: kgilbert@astro.washington.edu, E-mail: dweisz@astro.washington.edu, E-mail: aseth@cfa.harvard.edu, E-mail: skillman@astro.umn.edu, E-mail: adolphin@raytheon.com [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85756 (United States)

    2011-07-01T23:59:59.000Z

    We present deep Hubble Space Telescope WFPC2 optical observations obtained as part of the ACS Nearby Galaxy Survey Treasury as well as early release Wide Field Camera 3 ultraviolet and infrared observations of the nearby dwarf starbursting galaxy NGC 4214. Our data provide a detailed example of how covering such a broad range in wavelength provides a powerful tool for constraining the physical properties of stellar populations. The deepest data reach the ancient red clump at M{sub F814W} {approx} - 0.2. All of the optical data reach the main-sequence turnoff for stars younger than {approx}300 Myr and the blue He-burning sequence for stars younger than 500 Myr. The full color-magnitude diagram (CMD) fitting analysis shows that all three fields in our data set are consistent with {approx}75% of the stellar mass being older than 8 Gyr, in spite of showing a wide range in star formation rates at present. Thus, our results suggest that the scale length of NGC 4214 has remained relatively constant for many gigayears. As previously noted by others, we also find the galaxy has recently ramped up production consistent with its bright UV luminosity and its population of UV-bright massive stars. In the central field we find UV point sources with F336W magnitudes as bright as -9.9. These are as bright as stars with masses of at least 52-56 M{sub sun} and ages near 4 Myr in stellar evolution models. Assuming a standard initial mass function, our CMD is well fitted by an increase in star formation rate beginning 100 Myr ago. The stellar populations of this late-type dwarf are compared with those of NGC 404, an early-type dwarf that is also the most massive galaxy in its local environment. The late-type dwarf appears to have a similar high fraction of ancient stars, suggesting that these dominant galaxies may form at early epochs even if they have low total mass and very different present-day morphologies.

  12. Sweetspot: Near-infrared observations of 13 type Ia supernovae from a new NOAO survey probing the nearby smooth Hubble flow

    SciTech Connect (OSTI)

    Weyant, Anja; Wood-Vasey, W. Michael [Pittsburgh Particle physics, Astrophysics, and Cosmology Center (PITT PACC), Physics and Astronomy Department, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Allen, Lori; Joyce, Richard; Matheson, Thomas [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Garnavich, Peter M. [Department of Physics, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); Jha, Saurabh W., E-mail: anw19@pitt.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ 08854 (United States)

    2014-04-01T23:59:59.000Z

    We present 13 Type Ia supernovae (SNe Ia) observed in the rest-frame near-infrared (NIR) from 0.02 < z < 0.09 with the WIYN High-resolution Infrared Camera on the WIYN 3.5 m telescope. With only one to three points per light curve and a prior on the time of maximum from the spectrum used to type the object, we measure an H-band dispersion of spectroscopically normal SNe Ia of 0.164 mag. These observations continue to demonstrate the improved standard brightness of SNe Ia in an H band, even with limited data. Our sample includes two SNe Ia at z ? 0.09, which represent the most distant rest-frame NIR H-band observations published to date. This modest sample of 13 NIR SNe Ia represent the pilot sample for {sup S}weetSpot{sup —}a 3 yr NOAO Survey program that will observe 144 SNe Ia in the smooth Hubble flow. By the end of the survey we will have measured the relative distance to a redshift of z ? 0.05%-1%. Nearby Type Ia supernova (SN Ia) observations such as these will test the standard nature of SNe Ia in the rest-frame NIR, allow insight into the nature of dust, and provide a critical anchor for future cosmological SN Ia surveys at higher redshift.

  13. A planetary system around the nearby M dwarf GJ 667C with at least one super-Earth in its habitable zone

    E-Print Network [OSTI]

    Anglada-Escudé, Guillem; Vogt, Steven S; Rivera, Eugenio J; Butler, R Paul; Crane, Jeffrey D; Shectman, Stephen A; Thompson, Ian B; Minniti, Dante; Haghighipour, Nader; Carter, Brad D; Tinney, C G; Wittenmyer, Robert A; Bailey, Jeremy A; O'Toole, Simon J; Jones, Hugh R A; Jenkins, James S

    2012-01-01T23:59:59.000Z

    We re-analyze 4 years of HARPS spectra of the nearby M1.5 dwarf GJ 667C available through the ESO public archive. The new radial velocity (RV) measurements were obtained using a new data analysis technique that derives the Doppler measurement and other instrumental effects using a least-squares approach. Combining these new 143 measurements with 41 additional RVs from the Magellan/PFS and Keck/HIRES spectrometers, reveals 3 additional signals beyond the previously reported 7.2-day candidate, with periods of 28 days, 75 days, and a secular trend consistent with the presence of a gas giant (Period sim 10 years). The 28-day signal implies a planet candidate with a minimum mass of 4.5 Mearth orbiting well within the canonical definition of the star's liquid water habitable zone, this is, the region around the star at which an Earth-like planet could sustain liquid water on its surface. Still, the ultimate water supporting capability of this candidate depends on properties that are unknown such as its albedo, atmo...

  14. A radio jet drives a molecular & atomic gas outflow in multiple regions within one square kiloparsec of the nucleus of the nearby galaxy IC5063

    E-Print Network [OSTI]

    Dasyra, K M; Combes, F; Vlahakis, N

    2015-01-01T23:59:59.000Z

    We analyzed near-infrared data of the nearby galaxy IC5063 taken with the Very Large Telescope SINFONI instrument. IC5063 is an elliptical galaxy that has a radio jet nearly aligned with the major axis of a gas disk in its center. The data reveal multiple signatures of molecular and atomic gas that has been kinematically distorted by the jet passage within an area of ~1 kpc^2. Concrete evidence that the impact of jet plasma upon gas causes the gas to accelerate comes from outflows detected near four different bending points of the jet: at the two bright radio lobes, near a diverted plasma stream close to the north lobe, and near the tip of a plasma stream in the narrow-line region. Gas moving with a velocity excess of 600 km/s to 1200 km/s with respect to ordered motions is detected in [FeII], Paa, and H2 lines. Around these regions, gas is scattered in different directions. Near the north lobe, the highly blueshifted and the highly redshifted [FeII] emission is offset by 240 pc. The (scattered or not) plasma...

  15. A SEARCH FOR L/T TRANSITION DWARFS WITH Pan-STARRS1 AND WISE: DISCOVERY OF SEVEN NEARBY OBJECTS INCLUDING TWO CANDIDATE SPECTROSCOPIC VARIABLES

    SciTech Connect (OSTI)

    Best, William M. J.; Liu, Michael C.; Magnier, Eugene A.; Aller, Kimberly M.; Burgett, W. S.; Chambers, K. C.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Tonry, J. L.; Wainscoat, R. J. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Deacon, Niall R. [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Dupuy, Trent J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Redstone, Joshua [Facebook, 335 Madison Ave, New York, NY 10017-4677 (United States); Price, P. A., E-mail: wbest@ifa.hawaii.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2013-11-10T23:59:59.000Z

    We present initial results from a wide-field (30,000 deg{sup 2}) search for L/T transition brown dwarfs within 25 pc using the Pan-STARRS1 and Wide-field Infrared Survey Explorer (WISE) surveys. Previous large-area searches have been incomplete for L/T transition dwarfs, because these objects are faint in optical bands and have near-infrared (near-IR) colors that are difficult to distinguish from background stars. To overcome these obstacles, we have cross-matched the Pan-STARRS1 (optical) and WISE (mid-IR) catalogs to produce a unique multi-wavelength database for finding ultracool dwarfs. As part of our initial discoveries, we have identified seven brown dwarfs in the L/T transition within 9-15 pc of the Sun. The L9.5 dwarf PSO J140.2308+45.6487 and the T1.5 dwarf PSO J307.6784+07.8263 (both independently discovered by Mace et al.) show possible spectroscopic variability at the Y and J bands. Two more objects in our sample show evidence of photometric J-band variability, and two others are candidate unresolved binaries based on their spectra. We expect our full search to yield a well-defined, volume-limited sample of L/T transition dwarfs that will include many new targets for study of this complex regime. PSO J307.6784+07.8263 in particular may be an excellent candidate for in-depth study of variability, given its brightness (J = 14.2 mag) and proximity (11 pc)

  16. CHARACTERIZATION OF THE NEARBY L/T BINARY BROWN DWARF WISE J104915.57-531906.1 AT 2 pc FROM THE SUN

    SciTech Connect (OSTI)

    Kniazev, A. Y.; Vaisanen, P.; Potter, S. B.; Crawford, S.; Gulbis, A. A. S. [South African Astronomical Observatory, P.O. Box 9, 7935 Observatory, Cape Town (South Africa); Muzic, K.; Mehner, A.; Boffin, H. M. J.; Melo, C.; Ivanov, V. D.; Girard, J.; Mawet, D.; Schmidtobreick, L. [European Southern Observatory, Ave. Alonso de Cordova 3107, Casilla 19001, Santiago 19 (Chile); Kurtev, R.; Borissova, J. [Departamento de Fisica y Astronomia, Universidad de Valparaiso, Av. Gran Bretana 1111, Playa Ancha, 5030 Casilla (Chile); Huelamo, N. [CAB (INTA-CSIC), LAEFF, P.O. Box 78, E-28691 Villanueva de la Canada, Madrid (Spain); Minniti, D. [Departamento Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Av. Vicuna Mackenna 4860, Santiago (Chile); Ishibashi, K. [Nagoya University, Nagoya (Japan); Beletsky, Y. [Las Campanas Observatory, Carnegie Institution of Washington, Colina el Pino, Casilla 601 La Serena (Chile); Buckley, D. A. H. [Southern African Large Telescope Foundation, P.O. Box 9, 7935 Observatory, Cape Town (South Africa); and others

    2013-06-20T23:59:59.000Z

    WISE J104915.57-531906.1 is a L/T brown dwarf binary located 2 pc from the Sun. The pair contains the closest known brown dwarfs and is the third closest known system, stellar or sub-stellar. We report comprehensive follow-up observations of this newly uncovered system. We have determined the spectral types of both components (L8 {+-} 1, for the primary, agreeing with the discovery paper; T1.5 {+-} 2 for the secondary, which was lacking spectroscopic type determination in the discovery paper) and, for the first time, their radial velocities (V{sub rad} {approx} 23.1, 19.5 km s{sup -1}) using optical spectra obtained at the Southern African Large Telescope and other facilities located at the South African Astronomical Observatory (SAAO). The relative radial velocity of the two components is smaller than the range of orbital velocities for theoretically predicted masses, implying that they form a gravitationally bound system. We report resolved near-infrared JHK{sub S} photometry from the Infrared Survey Facility telescope at the SAAO which yields colors consistent with the spectroscopically derived spectral types. The available kinematic and photometric information excludes the possibility that the object belongs to any of the known nearby young moving groups or associations. Simultaneous optical polarimetry observations taken at the SAAO 1.9 m give a non-detection with an upper limit of 0.07%. For the given spectral types and absolute magnitudes, 1 Gyr theoretical models predict masses of 0.04-0.05 M{sub Sun} for the primary, and 0.03-0.05 M{sub Sun} for the secondary.

  17. A Sub-Millimeter Search of Nearby Young Stars for Cold Dust: Discovery of Debris Disks around Two Low-Mass Stars

    E-Print Network [OSTI]

    Michael C. Liu; Brenda C. Matthews; Jonathan P. Williams; Paul G. Kalas

    2004-04-07T23:59:59.000Z

    (Abridged) We present results from a JCMT/SCUBA 850 um search for cold dust around nearby young stars belonging to the beta Pic (t~12 Myr) and the Local Association (t~50 Myr) moving groups. Unlike most past sub-mm studies, our sample was chosen on the basis of stellar age. Our observations achieve about an order of magnitude greater sensitivity in dust mass compared to previous work in this age range. We detected two of the three M dwarfs in our sample at 850 um, GJ 182 and GJ 803. GJ 182 may also possess a 25 um excess, indicative of warm dust in the inner few AU of its disk. For GJ 803 (AU Mic), sub-mm mapping finds that the 850 um emission is unresolved. A non-detection of the CO 3-2 line indicates the system is gas-poor, and the SED suggests the presence of a large inner disk hole (~17 AU = 1.7 arcsec in radius). These are possible indications that planets at large separations can form around M dwarfs within \\~10 Myr. In a companion paper (Kalas, Liu & Matthews 2004), we confirm the existence of a dust disk around GJ 803 using optical coronagraphic imaging. Given its youthfulness, proximity, and detectability, the GJ 803 disk will be a valuable system for studying disk, and perhaps planet, formation in great detail. Overall, sub-mm measurements of debris disks point to a drop in dust mass by a factor of about 10^3 within the first ~10 Myr, with the subsequent decline in the masses of sub-mm detected disks consistent with t^{-0.5} to t^{-1}.

  18. THE ASYMPTOTIC GIANT BRANCH AND THE TIP OF THE RED GIANT BRANCH AS PROBES OF STAR FORMATION HISTORY: THE NEARBY DWARF IRREGULAR GALAXY KKH 98

    SciTech Connect (OSTI)

    Melbourne, J. [Caltech Optical Observatories, Division of Physics, Mathematics and Astronomy, Mail Stop 301-17, California Institute of Technology, Pasadena, CA 91125 (United States); Williams, B.; Dalcanton, J. [Department of Astronomy, Box 351580, University of Washington, Seattle, WA 98195 (United States); Ammons, S. M.; Max, C.; Koo, D. C. [University of California Observatories/Lick Observatory, Department of Astronomy and Astrophysics, University of California at Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Girardi, Leo [Osservatorio Astronomico di Padova-INAF, Padova (Italy); Dolphin, A., E-mail: jmel@caltech.ed, E-mail: ben@astro.washington.ed, E-mail: jd@astro.washington.ed, E-mail: ammons@ucolick.or, E-mail: max@ucolick.or, E-mail: koo@ucolick.or, E-mail: leo.girardi@oapd.inaf.i, E-mail: adolphin@raytheon.co [Raytheon, 1151 E. Hermans Road, Tucson, AZ 85706 (United States)

    2010-03-20T23:59:59.000Z

    We investigate the utility of the asymptotic giant branch (AGB) and the red giant branch (RGB) as probes of the star formation history (SFH) of the nearby (D = 2.5 Mpc) dwarf irregular galaxy, KKH 98. Near-infrared (near-IR) Keck Laser Guide Star Adaptive Optics (AO) images resolve 592 IR-bright stars reaching over 1 mag below the tip of the RGB. Significantly deeper optical (F475W and F814W) Hubble Space Telescope images of the same field contain over 2500 stars, reaching to the red clump and the main-sequence turnoff for 0.5 Gyr old populations. Compared to the optical color-magnitude diagram (CMD), the near-IR CMD shows significantly tighter AGB sequences, providing a good probe of the intermediate-age (0.5-5 Gyr) populations. We match observed CMDs with stellar evolution models to recover the SFH of KKH 98. On average, the galaxy has experienced relatively constant low-level star formation (5 x 10{sup -4} M{sub sun} yr{sup -1}) for much of cosmic time. Except for the youngest main-sequence populations (age <0.1 Gyr), which are typically fainter than the AO data flux limit, the SFH estimated from the 592 IR-bright stars is a reasonable match to that derived from the much larger optical data set. Differences between the optical- and IR-derived SFHs for 0.1-1 Gyr populations suggest that current stellar evolution models may be overproducing the AGB by as much as a factor of 3 in this galaxy. At the depth of the AO data, the IR-luminous stars are not crowded. Therefore, these techniques can potentially be used to determine the stellar populations of galaxies at significantly further distances.

  19. avamereregati tall ships: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010 Major Subject: Anthropology iii ABSTRACT Extracting Cultural Information from Ship Timber. (December 2010... Creasman, Pearce 2012-02-14 114 Pollution control: A Houston...

  20. At 200 feet tall, the Tower at Sandia National Laboratories

    E-Print Network [OSTI]

    for near earth stationary objects in space. Test Bed Dish Concentrators 36' diameter dishes each produce 75 with 2 axis control. Solar Furnace To protect equipment, this dish is in a fixed configuration inside collecting systems plus protected viewing from the control room. Rotating Platform Outdoor 10'x 20' platform

  1. Scientific American: "Tall Trees Sucked Dry by Global Warming...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    change research at Los Alamos Lab "PBS NEWSHOUR" covers new technique that may make solar panel production less expensive The New York Times covers "National Labs Race to...

  2. TALL : rethinking the systems of the contemporary high rise

    E-Print Network [OSTI]

    Namkung, Kenneth, 1977-

    2003-01-01T23:59:59.000Z

    The life of modern work is complex. What once entailed simple activities encapsulated within simple and hierarchically designed spaces has evolved into a highly volatile and complex organism. Businesses and workers are ...

  3. Decommissioning a 60-m-tall exhaust stack

    SciTech Connect (OSTI)

    Louie, R.L.; Speer, D.R. (Westinghouse Hanford Co., Richland, WA (USA))

    1989-08-01T23:59:59.000Z

    The decommissioning of the Strontium Semiworks Complex, located in the 200 East Area of the Hanford Site, is nearing completion. This facility operated as a pilot plant from 1949 to 1967 to develop fuel reprocessing technology and a method for separating strontium from high-level liquid wastes. Contamination of the facility from these operations was extensive. One of the major activities completed was the decommissioning of the plant exhaust stack. Demolition of the stack was accomplished using explosives. This required decontamination of the stack interior to minimize the release of airborne contamination. Radiation levels in the stack prior to cleaning ranged from 2.5 to 90 mGy/h as measured along the stack centerline. Decontamination was accomplished by sandblasting, using equipment specially designed and fabricated to allow the work to be performed remotely.

  4. Evaluation of Gas Retention in Waste Simulants: Tall Column Experiments

    SciTech Connect (OSTI)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Shimskey, Rick W.; Denslow, Kayte M.; Powell, Michael R.; Boeringa, Gregory K.; Bontha, Jagannadha R.; Karri, Naveen K.; Fifield, Leonard S.; Tran, Diana N.; Sande, Susan; Heldebrant, David J.; Meacham, Joseph E.; Smet, Dave; Bryan, Wesley E.; Calmus, Ronald B.

    2014-05-16T23:59:59.000Z

    Gas generation in Hanford’s underground waste storage tanks can lead to gas accumulation within the layer of settled solids (sludge) at the tank bottom. The gas, which typically has hydrogen as the major component together with other flammable species, is formed principally by radiation-driven chemical reactions. Accumulation of these gases within the sludge in a waste tank is undesirable and limits the amount of tank volume for waste storage. Further, accumulation of large amounts of gas in the sludge may potentially result in an unacceptable release of the accumulated gas if the sludge-layer density is reduced to less than that of the overlying sludge or that of the supernatant liquid. Rapid release of large amounts of flammable gases could endanger personnel and equipment near the tank. For this reason, a thorough understanding of the circumstances that can lead to a potentially problematic gas accumulation in sludge layers is needed. To respond to this need, the Deep Sludge Gas Release Event Program (DSGREP) was commissioned to examine gas release behavior in sludges.

  5. Factors affecting coking pressures in tall coke ovens

    SciTech Connect (OSTI)

    Grimley, J.J.; Radley, C.E. [British Steel plc, Scunthorpe (United Kingdom). Scunthorpe Works

    1995-12-01T23:59:59.000Z

    The detrimental effects of excessive coking pressures, resulting in the permanent deformation of coke oven walls, have been recognized for many years. Considerable research has been undertaken worldwide in attempts to define the limits within which a plant may safely operate and to quantify the factors which influence these pressures. Few full scale techniques are available for assessing the potential of a coal blend for causing wall damage. Inference of dangerous swelling pressures may be made however by the measurement of the peak gas pressure which is generated as the plastic layers meet and coalesce at the center of the oven. This pressure is referred to in this report as the carbonizing pressure. At the Dawes Lane cokemaking plant of British Steel`s Scunthorpe Works, a large database has been compiled over several years from the regulator measurement of this pressure. This data has been statistically analyzed to provide a mathematical model for predicting the carbonizing pressure from the properties of the component coals, the results of this analysis are presented in this report.

  6. Improving UK greenhouse gas emission estimates using tall tower observations 

    E-Print Network [OSTI]

    Howie, James Edward

    2014-06-30T23:59:59.000Z

    Greenhouse gases in the Earth’s atmosphere play an important role in regulating surface temperatures. The UK is signatory to international agreements that legally commit the UK to reduce its greenhouse gas emissions, and ...

  7. Negative Resists for Ultra-Tall, High Aspect Ratio Microstructures

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparency VisitSilver Toyota1ResourceloadingOurAlamosNedResists for

  8. NUMERICAL SOLUTION OF AN INVERSE OBSTACLE ...

    E-Print Network [OSTI]

    2015-01-25T23:59:59.000Z

    n?Z. An exp(in?),. (2.6) where An and An are constants. Adding (2.2) and (2.5), ...... [10] T. Cheng, P. Li, and Y. Wang, Near-field imaging of perfectly conducting

  9. On smooth relaxations of obstacle sets

    E-Print Network [OSTI]

    2011-08-18T23:59:59.000Z

    Aug 18, 2011 ... Institute of Operations Research, Karlsruhe Institute of Technology, .... quel the family of functions (?t , t > 0) will have to satisfy the following.

  10. Off-road obstacle classification and traversability analysis in the presence of negative obstacles

    E-Print Network [OSTI]

    Larson, Jacoby

    2011-01-01T23:59:59.000Z

    those areas that are the most hazardous. Classificationin the area of mobility in the face of hazardous terrain.

  11. Off-road obstacle classification and traversability analysis in the presence of negative obstacles

    E-Print Network [OSTI]

    Larson, Jacoby

    2011-01-01T23:59:59.000Z

    2.5D multi-level surface map grid representation (image03], or 3D map. A 2D grid map, also known as an occupancyquick to search. The 3D grid map is made up of voxels that

  12. GRB 130427A: A Nearby Ordinary Monster

    E-Print Network [OSTI]

    Napp, Nils

    ,13 K. Wiersema,8 Y. Yatsu,5 T. Yoshii,5 G. Tagliaferri2 Long-duration gamma-ray bursts (GRBs at 95 GeV (2). It was detected with Fermi­Gamma-ray Burst Mon- itor (GBM) (3) at T0, GBM = 47:06.42 UTon and over the full range of GRB isotropic energies. G amma-ray burst (GRB) 130427Awas the brightest burst

  13. NEARBY GALAXIES IN MORE DISTANT CONTEXTS

    SciTech Connect (OSTI)

    Eskew, Michael; Zaritsky, Dennis, E-mail: meskew@email.arizona.edu, E-mail: dzaritsky@as.arizona.edu [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2011-02-15T23:59:59.000Z

    We use published reconstructions of the star formation history (SFH) of the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and NGC 300 from the analysis of resolved stellar populations to investigate where such galaxies might land on well-known extragalactic diagnostic plots over the galaxies' lifetime (assuming that nothing other than their stellar populations change). For example, we find that the evolution of these galaxies implies a complex evolution in the Tully-Fisher relation with look-back time and that the observed scatter is consistent with excursions these galaxies take as their stellar populations evolve. We find that the growth of stellar mass is weighted to early times, despite the strongly star-forming current nature of the three systems. Lastly, we find that these galaxies can take circuitous paths across the color-magnitude diagram. For example, it is possible, within the constraints provided by the current determination of its SFH, that the LMC reached the red sequence at intermediate age prior to ending back up on the blue cloud at the current time. Unfortunately, this behavior happens at sufficiently early times that our resolved SFH is crude and insufficiently constraining to convincingly demonstrate that this was the actual evolutionary path. The limited sample size precludes any general conclusions, but we present these as examples how we can bridge the study of resolved populations and the more distant universe.

  14. Lithium Depletion of Nearby Young Stellar Associations

    E-Print Network [OSTI]

    Erin Mentuch; Alexis Brandeker; Marten H. van Kerkwijk; Ray Jayawardhana; Peter H. Hauschildt

    2008-08-26T23:59:59.000Z

    We estimate cluster ages from lithium depletion in five pre-main-sequence groups found within 100 pc of the Sun: TW Hydrae Association, Eta Chamaeleontis Cluster, Beta Pictoris Moving Group, Tucanae-Horologium Association and AB Doradus Moving Group. We determine surface gravities, effective temperatures and lithium abundances for over 900 spectra through least squares fitting to model-atmosphere spectra. For each group, we compare the dependence of lithium abundance on temperature with isochrones from pre-main-sequence evolutionary tracks to obtain model dependent ages. We find that the Eta Chamaelontis Cluster and the TW Hydrae Association are the youngest, with ages of 12+/-6 Myr and 12+/-8 Myr, respectively, followed by the Beta Pictoris Moving Group at 21+/-9 Myr, the Tucanae-Horologium Association at 27+/-11 Myr, and the AB Doradus Moving Group at an age of at least 45 Myr (where we can only set a lower limit since the models -- unlike real stars -- do not show much lithium depletion beyond this age). Here, the ordering is robust, but the precise ages depend on our choice of both atmospheric and evolutionary models. As a result, while our ages are consistent with estimates based on Hertzsprung-Russell isochrone fitting and dynamical expansion, they are not yet more precise. Our observations do show that with improved models, much stronger constraints should be feasible: the intrinsic uncertainties, as measured from the scatter between measurements from different spectra of the same star, are very low: around 10 K in effective temperature, 0.05 dex in surface gravity, and 0.03 dex in lithium abundance.

  15. Dynamics of the Disks of Nearby Galaxies

    E-Print Network [OSTI]

    B. Fuchs

    2008-10-20T23:59:59.000Z

    I describe how the dynamics of galactic disks can be inferred by imaging and spectroscopy. Next I demonstrate that the decomposition of the rotation curves of spiral galaxies into the contributions by the various components of the galaxies is highly degenerate. Constraints on the decomposition can be found by considering implications for the dynamics of the galactic disks. An important diagnostic is the Toomre Q stability parameter which controls the stability of a galactic disk against local Jeans collapse. I also show how the density wave theory of galactic spiral arms can be employed to constrain the mass of a galactic disk. Applying both diagnostics to the example of NGC 2985 and discussing also the implied mass-to-light ratio I demonstrate that the inner parts of the galaxy, where the optical disk resides, are dominated by baryons. When I apply this method to the disks of low surface brightness galaxies, I find unexpectedly high mass-to light ratios. These could be explained by population synthesis models which assume a bottom heavy initial mass function similar to the recently proposed `integrated galactic initial mass function'.

  16. The Nearby Supernova Factory Ozone + Aerosol + Rayleigh

    E-Print Network [OSTI]

    Rayleigh + Aerosol Extinction monitor filter Auxiliary Camera CCD Spectrograph picko ff mirror Umbra

  17. Overview of the nearby supernova factory

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    from 42 High-Redshift Supernovae,” Astrophys J. 517, pp.Observational Evidence from Supernovae for an AcceleratingCalan/Tololo Type Ia Supernovae,” Astron. J. 112, p. 2391,

  18. A high resolution view of the jet termination shock in a hot spot of the nearby radio galaxy Pictor A: implications for X-ray models of radio galaxy hot spots

    E-Print Network [OSTI]

    S. J. Tingay; E. Lenc; G. Brunetti; M. Bondi

    2008-10-02T23:59:59.000Z

    Images made with the VLBA have resolved the region in a nearby radio galaxy, Pictor A, where the relativistic jet that originates at the nucleus terminates in an interaction with the intergalactic medium, a so-called radio galaxy hot spot. This image provides the highest spatial resolution view of such an object to date (16 pc), more than three times better than previous VLBI observations of similar objects. The north-west Pictor A hot spot is resolved into a complex set of compact components, seen to coincide with the bright part of the hot spot imaged at arcsecond-scale resolution with the VLA. In addition to a comparison with VLA data, we compare our VLBA results with data from the HST and Chandra telescopes, as well as new Spitzer data. The presence of pc-scale components in the hot spot, identifying regions containing strong shocks in the fluid flow, leads us to explore the suggestion that they represent sites of synchrotron X-ray production, contributing to the integrated X-ray flux of the hot spot, along with X-rays from synchrotron self-Compton scattering. This scenario provides a natural explanation for the radio morphology of the hot spot and its integrated X-ray emission, leading to very different predictions for the higher energy X-ray spectrum compared to previous studies. From the sizes of the individual pc-scale components and their angular spread, we estimate that the jet width at the hot spot is in the range 70 - 700 pc, which is comparable to similar estimates in PKS 2153-69, 3C 205, and 4C 41.17. The lower limit in this range arises from the suggestion that the jet may dither in its direction as it passes through hot spot backflow material close to the jet termination point, creating a "dentist drill" effect on the inside of a cavity 700 pc in diameter.

  19. Obstacles and Opportunity: Overcoming Barriers in Today's CHP Marketplace

    E-Print Network [OSTI]

    Chittum, A.; Kaufman, N.

    2011-01-01T23:59:59.000Z

    Combined heat and power (CHP), which can offer tremendous efficiency benefits to industrial facilities around the country, continues to be viewed as a long-term efficiency opportunity. However, the high up-front cost of CHP equipment and fuel...

  20. ON THE GLOBAL SOLUTIONS OF THE PARABOLIC OBSTACLE PROBLEM

    E-Print Network [OSTI]

    Shahgholian, Henrik

    analysis is essential in studying the local properties of a free boundary. The idea to use information investigation in [CPS]. Notations and de#12;nitions. Throughout the paper we will use the following notations: z

  1. Mobile Robot Obstacle Avoidance Via Depth From Focus

    E-Print Network [OSTI]

    Tomasi, Carlo

    Abstract A critical challenge in the creation of autonomous mobile robots is the reliable detection radiation such as direct sunlight. In contrast, vision systems are passive and can provide lateral and depth market. However, our particular embodiment of this concept is remarkable because our focus-based system

  2. Medical waste management in Ibadan, Nigeria: Obstacles and prospects

    SciTech Connect (OSTI)

    Coker, Akinwale [Department of Civil Engineering, Faculty of Technology, University of Ibadan, Ibadan (Nigeria); School of Engineering and the Built Environment, University of Wolverhampton, Wolverhampton WV1 1SB (United Kingdom)], E-mail: cokerwale@yahoo.com; Sangodoyin, Abimbola [Department of Agricultural and Environmental Engineering, Faculty of Technology, University of Ibadan, Ibadan (Nigeria); Sridhar, Mynepalli [Division of Environmental Health, Faculty of Public Health, College of Medicine, University of Ibadan, Ibadan (Nigeria); Booth, Colin; Olomolaiye, Paul; Hammond, Felix [School of Engineering and the Built Environment, University of Wolverhampton, Wolverhampton WV1 1SB (United Kingdom)

    2009-02-15T23:59:59.000Z

    Quantification and characterization of medical waste generated in healthcare facilities (HCFs) in a developing African nation has been conducted to provide insights into existing waste collection and disposal approaches, so as to provide sustainable avenues for institutional policy improvement. The study, in Ibadan city, Nigeria, entailed a representative classification of nearly 400 healthcare facilities, from 11 local government areas (LGA) of Ibadan, into tertiary, secondary, primary, and diagnostic HCFs, of which, 52 HCFs were strategically selected. Primary data sources included field measurements, waste sampling and analysis and a questionnaire, while secondary information sources included public and private records from hospitals and government ministries. Results indicate secondary HCFs generate the greatest amounts of medical waste (mean of 10,238 kg/day per facility) followed by tertiary, primary and diagnostic HCFs, respectively. Characterised waste revealed that only {approx}3% was deemed infectious and highlights opportunities for composting, reuse and recycling. Furthermore, the management practices in most facilities expose patients, staff, waste handlers and the populace to unnecessary health risks. This study proffers recommendations to include (i) a need for sustained cooperation among all key actors (government, hospitals and waste managers) in implementing a safe and reliable medical waste management strategy, not only in legislation and policy formation but also particularly in its monitoring and enforcement and (ii) an obligation for each HCF to ensure a safe and hygienic system of medical waste handling, segregation, collection, storage, transportation, treatment and disposal, with minimal risk to handlers, public health and the environment.

  3. Overcoming the obstacles: life stories of scientists with learning disabilities

    E-Print Network [OSTI]

    Force, Crista Marie

    2009-05-15T23:59:59.000Z

    of most individuals with learning disabilities. The purpose of this research was to better understand the methods by which successful learning disabled scientists have overcome the barriers and challenges associated with their learning disabilities...

  4. THE TWO-PHASE FRACTIONAL OBSTACLE PROBLEM 1 ...

    E-Print Network [OSTI]

    2014-06-26T23:59:59.000Z

    development of new tools such as the Caffarelli-Silvestre extension, .... preliminary results on our problem: energy inequality, local boundedness, Weiss-

  5. Obstacles and Opportunity: Turbine Motorization in Refineries Today

    E-Print Network [OSTI]

    Feng, Hua; Liu, Jinghing; Liu, Xiang; Ahmad, Mushtaq; Deng, Alan

    2012-01-01T23:59:59.000Z

    Steam turbines have been widely used in oil refineries for driving pumps, compressors and other rotary machines. However, in recent years, the authors of this paper have seen substantial turbine motorization projects completed or being planned...

  6. On the shrinking obstacle limit in a viscous incompressible flow

    E-Print Network [OSTI]

    Maryland at College Park, University of

    -Miyakawa-Osada) but uniqueness was proved only very recently (Gallagher-Gallay). The existence in the full plane case uses L1 es

  7. Political obstacles to adopting congestion pricing in New York City

    E-Print Network [OSTI]

    Lynch, Patrick (Patrick Michael)

    2010-01-01T23:59:59.000Z

    In April 2007, New York City's Mayor Bloomberg released PlaNYC, a broad ranging set of planning initiatives for the city. A centerpiece of the plan was a congestion-pricing proposal for the downtown core in Manhattan. The ...

  8. Obstacles and Opportunity: Turbine Motorization in Refineries Today 

    E-Print Network [OSTI]

    Feng, Hua; Liu, Jinghing; Liu, Xiang; Ahmad, Mushtaq; Deng, Alan

    2012-01-01T23:59:59.000Z

    Steam turbines have been widely used in oil refineries for driving pumps, compressors and other rotary machines. However, in recent years, the authors of this paper have seen substantial turbine motorization projects completed or being planned...

  9. OPTIMAL CONTROL OF THE OBSTACLE FOR A PARABOLIC VARIATIONAL INEQUALITY

    E-Print Network [OSTI]

    Kentucky, University of

    variational inequalityis considered on a domain Q = (0 T), with Rn , a bounded domain with C1 boundary @ . Let inequalityby approximat- ing with a semilinearparabolic PDE. There the existenceof an optimal control

  10. Elliptic and parabolic problems with thin and Lipschitz obstacles

    E-Print Network [OSTI]

    Arshak Petrosyan

    2011-11-03T23:59:59.000Z

    Page 41 ...... For our generalization, however, iu and hu are too irregular and we have to average them to regain missing regularity: Hu(r) = r. ?r hu(t)dt = r. S+r.

  11. OBSTACLE-AVOIDING SIMILARITY METRICS AND SHORTEST PATH PROBLEMS

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    Foundation grant NSF CAREER CCF-0643597 and the 2009 University of Texas at San Antonio Presidential with guidelines which permit the inclusion as part of the Doctoral Dissertation the text of an original paper

  12. NREL Overcomes Obstacles in Lignin Valorization (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2015-01-01T23:59:59.000Z

    This NREL Highlight is being produced for the 2015 February Alliance S&T Board meeting, and describes research that shows lignin can be converted into renewable fuels, chemicals, and materials.

  13. Microsoft Word - THE EFFECT OF OBSTACLE#4781.doc

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer Plant JumpMarysville, Ohio:Menomonee| OpenMickey HotVII, Cologne, Germany, 29

  14. Native American Housing: Obstacles and Opportunities | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of Contamination in Many DevilsForum |Energy NovemberC O ORH E N A T IDepartment

  15. Effects of a tuned mass damper on wind-induced motions in tall buildings

    E-Print Network [OSTI]

    Carlot, Julien (Julien Alexandre Laurent)

    2012-01-01T23:59:59.000Z

    With ever increasing constructability capacities, engineers have found solutions to build taller and taller structures. However, the race for the sky has not only brought up new ways of building, it has also created new ...

  16. Small Molecule that Reverses Dexamethasone Resistance in Tcell Acute Lymphoblastic Leukemia (T-ALL)

    E-Print Network [OSTI]

    Stockwell, Brent R.

    Small Molecule that Reverses Dexamethasone Resistance in Tcell Acute Lymphoblastic Leukemia (T are one of the most utilized and effective therapies in treating T-cell acute lymphoblastic leukemia lymphoblastic leukemia, dexamethasone, glucocorticoid resistance, NOTCH1 Acute lymphoblastic leukemia (ALL

  17. A systems approach to conceptual design solutions for a very tall building in Hong Kong

    E-Print Network [OSTI]

    Ungerer, Frank Wolfgang, 1969-

    1998-01-01T23:59:59.000Z

    The thesis represents a design investigation that seeks to reconsider the high-rise building. With changing uses and technologies, high-rise office towers may have become obsolete. Given the recent capabilities for ...

  18. Building optimization : an integrated approach to the design of tall buildings

    E-Print Network [OSTI]

    Coleman, Keith LaMar

    2007-01-01T23:59:59.000Z

    There has been much research done on building optimization that deal with the issues within specific individual fields, such as architecture, structural engineering, and construction engineering. However, in practical ...

  19. Strategies for mitigating wind-induced motion in tall buildings through aerodynamic and damping modifications

    E-Print Network [OSTI]

    Nnamani, Nnabuihe

    2012-01-01T23:59:59.000Z

    The advent of modern structural systems, spurred by advances in construction methodology and high strength materials, has driven the height of modern skyscrapers beyond what was once deemed possible. Although science and ...

  20. Wind shear for large wind turbine generators at selected tall tower sites

    SciTech Connect (OSTI)

    Elliott, D.L.

    1984-04-01T23:59:59.000Z

    The objective of the study described in this report is to examine the nature of wind shear profiles and their variability over the height of large horizontal-axis wind turbines and to provide information on wind shear relevant to the design and opertion of large wind turbines. Wind turbine fatigue life and power quality are related through the forcing functions on the blade to the shapes of the wind shear profiles and their fluctuations over the disk of rotation.

  1. RECIPIENT:Desert Research Institute STATE:NV PROJECT Tall Tower...

    Broader source: Energy.gov (indexed) [DOE]

    A9 Information gathering (including, but not limited to, literature surveys, inventories, audits), data analYSis (including computer modeling), document preparation (such...

  2. Acclimatization of soil respiration to warming in a tall grass prairie

    E-Print Network [OSTI]

    to climatic warming2±4 . The feedback mechanism is usually based on the assumption that observed sensitivity feedbacks into the climatic system. Climatic warming, on one hand, potentially stimulates nutrient) since 21 November 1999 to study respiratory sensitivity to climate change. We also used clipping

  3. Chemical characterization of acidic components in a commercial depitching of crude tall oil 

    E-Print Network [OSTI]

    Tsurumi, Toshio

    1982-01-01T23:59:59.000Z

    of Constituents in CTO Saps: 30m SP-2330 Glass Capillary Column. FRN: 21790 . VII. Assignment of Constituents in TOD Saps: 30m SP-2330 Glass Capillary Column. FRN: 21628 . VIII. Assignment of Constituents in CTO Saps: 25m DB-5 Fused Silica Capillary Column.... FRN: ZI637 IX. Assignment of Constituents in TOD Saps: 25m DB-5 Fused Silica Capillary Column. FRN: 21705 X. Assignment of Constituents in TOP Saps: 25m DB-5 Fused Silica Capillary Column. FRN: 21638 XI. List of Chromatograms XII. Response...

  4. Jointly organised by Centre for Asian Tall Buildings and Urban Habitat

    E-Print Network [OSTI]

    Tam, Vincent W. L.

    for Infrastructure and Construction Industry Development THE UNIVERSITY OF HONG KONG Sustainable Building Design on climate change, the depletion of the earth's resources, widespread pollution, the concept of sustainable a building in operation down to the kinds of building materials used in its construction with emphasis

  5. Restoring Tallgrass Prairie and Grassland Bird Populations in Tall Fescue Pastures With Winter Grazing

    E-Print Network [OSTI]

    Sandercock, Brett K.

    ­6% de la biomasa ae´rea total en potreros pastoreados todo el an~o, del 1­34% en los potreros pastoreados en el invierno, y de 31­34% en el remanente de la vegetacio´n nativa. La abundancia y biomasa de

  6. Limits to recruitment of tall fescue plants in poplar silvopastoral systems of the Pampas, Argentina

    E-Print Network [OSTI]

    Nacional de San Luis, Universidad

    , Argentina M. P. Clavijo · P. S. Cornaglia · P. E. Gundel · M. Nordenstahl · E. G. Jobbagy Received: 28 grasslands, Argentina (Wright et al. 2000). Silvopastoral systems that combine cattle production and forestry, Argentina e-mail: mclavijo@agro.uba.ar P. E. Gundel Ca´tedra de Ecologi´a-IFEVA (CONICET), Facultad de

  7. Structural systems and tuned mass dampers of super-tall buildings : case study of Taipei 101

    E-Print Network [OSTI]

    Kourakis, Ioannis

    2007-01-01T23:59:59.000Z

    The design of the first generation of skyscrapers was based on strength. Heavy masonry cladding and wall curtains used at that period added a considerable amount of stiffness and damping to the structure. Inter-storey ...

  8. Tall concrete buildings subject to vertically moving fires: A case study approach 

    E-Print Network [OSTI]

    Fletcher, Ian A

    regarded as safe in a fire situation as concrete is non-flammable and exhibits highly insulating material properties. The majority of current research relating to the impact of fire on structures examines other forms of construction. Research of concrete...

  9. 6,000 Feet Long (over one mile) 550 Feet Tall

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    Kurdistan Worker's Party (PKK)Kurdistan Worker's Party (PKK) inin Turkey.Turkey. Turkish Govt. claims PKK

  10. Seismic Intensity Estimation of Tall Buildings in Earthquake Early Warning System

    E-Print Network [OSTI]

    Greer, Julia R.

    systematic (e.g., basin motions vs. rock motions). Current state-of-the-art in seismology provides realistic the source location and the user's location. The Green's functions are pre-calculated for different source

  11. Analysis of thermal fields generated by natural fires on the structural elements of tall buildings 

    E-Print Network [OSTI]

    Capote, Jorge A; Alvear, Daniel; Lazaro, Mariano; Espina, Pablo; Fletcher, Ian A; Welch, Stephen; Torero, Jose L

    The Windsor Tower in Madrid was involved in a major fire, on 12-13 February 2005, which caused extensive structural damage to the upper floors of the building. This fire has provoked intense interest amongst researchers ...

  12. Infrared Properties of Nearby Interacting Galaxies: from Spirals to ULIRGs

    E-Print Network [OSTI]

    V. Charmandaris

    2006-10-20T23:59:59.000Z

    I present a brief review of some of the mid-infrared properties of interacting galaxies as these were revealed using observations from the Infrared Space Observatory and Spitzer Space Telescope over the last decade. The variation of the infrared spectral energy distribution in interacting galaxies can be used as an extinction free tracer not only of the location of the star formation activity but also of the physical mechanism dominating their energy production.

  13. Fusion of calcium isotopes and of nearby systems

    SciTech Connect (OSTI)

    Stefanini, A. M. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy)

    2012-10-20T23:59:59.000Z

    Very recent data on {sup 40,48}Ca+{sup 40,48}Ca are presented. In all cases fusion hindrance far below the barrier has been observed. Coupled-channel effects influence the threshold energy for hindrance. The excitation functions of the two symmetric systems are similar, while the case of {sup 40}Ca+{sup 48}Ca is different both above and below the barrier, possibly due to couplings to transfer channels with Q > 0. Other systems in the same mass region show different trends that have to be related to the nuclear structure of the colliding nuclei. Investigating the behavior of lighter systems will be interesting also from the astrophysical point of view.

  14. GALAXY GROWTH BY MERGING IN THE NEARBY UNIVERSE

    SciTech Connect (OSTI)

    Jiang Tao; Hogg, David W.; Blanton, Michael R., E-mail: david.hogg@nyu.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

    2012-11-10T23:59:59.000Z

    We measure the mass growth rate by merging for a wide range of galaxy types. We present the small-scale (0.014 h {sup -1} {sub 70} Mpc < r < 11 h {sub 70} {sup -1} Mpc) projected cross-correlation functions w(r {sub p}) of galaxy subsamples from the spectroscopic sample of the NYU Value-Added Galaxy Catalog (5 Multiplication-Sign 10{sup 5} galaxies of redshifts 0.03 < z < 0.15) with galaxy subsamples from the Sloan Digital Sky Survey imaging (4 Multiplication-Sign 10{sup 7} galaxies). We use smooth fits to de-project the two-dimensional functions w(r {sub p}) to obtain smooth three-dimensional real-space cross-correlation functions {xi}(r) for each of several spectroscopic subsamples with each of several imaging subsamples. Because close pairs are expected to merge, the three-space functions and dynamical evolution time estimates provide galaxy accretion rates. We find that the accretion onto massive blue galaxies and onto red galaxies is dominated by red companions, and that onto small-mass blue galaxies, red and blue galaxies make comparable contributions. We integrate over all types of companions and find that at fixed stellar mass, the total fractional accretion rates onto red galaxies ({approx}3 h {sub 70} percent per Gyr) are greater than that onto blue galaxies ({approx}1 h {sub 70} percent per Gyr). These rates are almost certainly overestimates because we have assumed that all close pairs merge as quickly as the merger time that we used. One conclusion of this work is that if the total growth of red galaxies from z = 1 to z = 0 is mainly due to merging, the merger rates must have been higher in the past.

  15. Discovery of a Nearby Low-Surface-Brightness Spiral Galaxy

    E-Print Network [OSTI]

    W. B. Burton; R. Braun; R. A. M. Walterbos; C. G. Hoopes

    1998-10-27T23:59:59.000Z

    During the course of a search for compact, isolated gas clouds moving with anomalous velocities in or near our own Galaxy (Braun and Burton 1998 A&A, in press), we have discovered, in the data of the Leiden/Dwingeloo survey (Hartmann and Burton 1997, Atlas of Galactic Neutral Hydrogen, CUP) of Galactic hydrogen, the HI signature of a large galaxy, moving at a recession velocity of 282 km/s, with respect to our Galaxy. Deep multicolor and spectroscopic optical observations show the presence of star formation in scattered HII regions; radio HI synthesis interferometry confirms that the galaxy is rich in HI and has the rotation signature of a spiral galaxy; a submillimeter observation failed to detect the CO molecule. The radio and optical evidence combined suggest its classification as a low-surface-brightness spiral galaxy. It is located in close spatial and kinematic proximity to the galaxy NGC 6946. The newly-discovered galaxy, which we call Cepheus 1, is at a distance of about 6 Mpc. It is probably to be numbered amongst the nearest few LSB spirals.

  16. Cerro Prieto cold water injection: effects on nearby production wells

    E-Print Network [OSTI]

    Truesdell, A.H.

    2010-01-01T23:59:59.000Z

    cooperative program at the Cerro Prieto geothermal field.geothermal system: the Cerro Prieto field, Baja California,cold water entry in the Cerro Prieto geothermal reservoir

  17. ECOSYSTEM COMPONENT CHARACTERIZATION 461 Failing or nearby septic tank systems

    E-Print Network [OSTI]

    Pitt, Robert E.

    · Hazardous waste disposal sites · Naturally occurring toxicants and pollutants due to surrounding geological has been studied at many locations. The sources of the pathogens are typically assumed to be sanitary

  18. LIST OF HOSTELS AND HOTELS NEARBY HKU Attention please

    E-Print Network [OSTI]

    Tam, Vincent W. L.

    (1405'-1673') * Furnished with air-conditioning, TV, bathroom and telephone, duplex suite has kitchen. ft.) * Fully furnished, air-conditioning, refrigerator , TV, telephone, electrical water kettle) · Twin Room (public bathroom) (Approx. 75 - 210 sq. ft.) * Fully furnished, air-conditioning

  19. Cerro Prieto cold water injection: effects on nearby production wells

    E-Print Network [OSTI]

    Truesdell, A.H.

    2010-01-01T23:59:59.000Z

    CFE-DOE Symp. in Geothermal Energy, DOE CONF 8904129, pp.Proc. CFE-DOE Symp. in Geothermal Energy, DOE CONF 8904129,and Renewable Energy, Office of Geothermal Technologies, of

  20. The Photometric Properties of Nearby Type Ia Supernovae

    E-Print Network [OSTI]

    Ganeshalingam, Mohan

    2012-01-01T23:59:59.000Z

    1.1.1 Thermonuclear SNe . . . . . . 1.1.2 Core-Collapseby which they explode: thermonuclear and core collapse.thesis is focused on thermonuclear SNe, I describe the two

  1. Studies of nearby poor clusters - A3574 and S753

    SciTech Connect (OSTI)

    Willmer, C.N.A.; Focardi, P.; Chan, R.; Pellegrini, P.S.; Da Costa, N.L. (Observatorio Nacional do Brasil, Rio de Janeiro (Brazil))

    1991-01-01T23:59:59.000Z

    Photometric and spectroscopic data are presented for two clusters, A3574 and S753, belonging to the Centaurus concentration of galaxies. The masses of the clusters are estimated at 1.5 x 10 to the 14th solar masses; no evidence of substructure has been detected in either cluster. The solution of a two-body linear orbit suggests that the clusters do not form a bound system, although the result is marginal. 60 refs.

  2. Structural parameters of nearby emission-line galaxies

    E-Print Network [OSTI]

    Miguel Sanchez-Portal; Angeles I Diaz; Elena Terlevich; Roberto Terlevich

    2004-03-17T23:59:59.000Z

    We present the results of an investigation on the main structural properties derived from VRI and Halpha surface photometry of galaxies hosting nuclear emission-line regions (including Seyfert 1, Seyfert 2, LINER and starburst galaxies) as compared with normal galaxies. Our original sample comprises 22 active galaxies, 4 starbursts and 1 normal galaxy and has been extended with several samples obtained from the literature. Bulge and disc parameters, along with B/D relation, have been derived applying an iterative procedure. The resulting parameters have been combined with additional data in order to reach a statistically significant sample. We find some differences in the bulge distribution across the different nuclear types that could imply familes of bulges with different physical properties. Bulge and disc characteristic colours have been defined and derived for our sample and compared with a control sample of early type objects. The results suggest that bulge and disc stellar populations are comparable in normal and active galaxies.

  3. Investigating AGN Heating in a Sample of Nearby Clusters

    E-Print Network [OSTI]

    Dunn, R J H

    2006-01-01T23:59:59.000Z

    We analyse those objects in the Brightest 55 sample of clusters of galaxies which have a short central cooling time and a central temperature drop. Such clusters are likely to require some form of heating. Where clear radio bubbles are observed in these clusters, their energy injection is compared to the X-ray cooling rate. Of the 20 clusters requiring heating, at least 14 have clear bubbles, implying a duty cycle for the bubbling activity of at least 70 per cent. The average distance out to which the bubbles can offset the X-ray cooling, r_heat is given by r_heat/r_cool=0.86+/-0.11 where r_cool is defined as the radius as which the radiative cooling time is 3 Gyr. 10 out of 16 clusters have r_heat/r_cool>1, but there is a large range in values. The clusters which require heating but show no clear bubbles were combined with those clusters which have a radio core to form a second sub-sample. Using r_heat=0.86 r_cool we calculate the size of an average bubble expected in these clusters. In five cases (3C129.1, ...

  4. Collection: Supernova Discoveries from the Nearby Supernova Factory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i tCollaboration March 16, 2010of

  5. The effects of seeding rate, row spacing and rates of fertilizer on a short Vs a tall wheat variety

    E-Print Network [OSTI]

    Rao, Srinivas Chamkurgopal

    1968-01-01T23:59:59.000Z

    per square foot 20 Analysis of variance 8 square feet for winter forage, grams per 21 Analysis of variance square foot for number of heads per 23 Analysis of variance for number of seeds per he ad 24 Analysis of variance for 100-seed weight... of plants per square foot 41 Average dry weight of winter forage in grams per 8 square foot 42 3. Average number of heads per square foot 4. Average number of seeds per head 5. Average weight of 100 seed in grams 6 Average yield of grain in bushels per...

  6. Use of Computer Simulation to Reduce the Energy Consumption in a Tall Office Building in Dubai-UAE 

    E-Print Network [OSTI]

    Abu-Hijleh, B.; Abu-Dakka, M.

    2010-01-01T23:59:59.000Z

    increasing the cooling load due to its heat dissipation. Proper design for the maximization of natural light helps reduce the use of artificial lights and results in reduction in the buildings energy consumption. Computer simulation of the lighting and energy...

  7. Use of Computer Simulation to Reduce the Energy Consumption in a Tall Office Building in Dubai-UAE

    E-Print Network [OSTI]

    Abu-Hijleh, B.; Abu-Dakka, M.

    2010-01-01T23:59:59.000Z

    ,200 kilowatt hours per square meter, and the direct illumination falling to the earth exceeds 90000 lux in summer, the second highest in the world (Al-Sallal and Ahmed, 2007). Being on the tropic of cancer (24 deg N) results in that the UAE region...: 3D Max Design, Radiance and Daysim. Reinhart and Fitz (2009) investigated the performance of the above three programs (3D Max Design, Radiance and Daysim) through running of daylighting simulations for a room and comparing the results...

  8. We all know that the Earth has tall mountains, but compared to its size these are actually very

    E-Print Network [OSTI]

    - gering 78,000 feet (24,000 meters) it is the tallest mountain in the solar system! Olympus Mons Stands of its location near the equator, the peak of Mt. Chimborazo, in Ecuador, rises farther from the center, in the Andes of Ecuador, is 20,703 feet (6310 meters) above sea level. But, because Ecuador is near the equator

  9. Forty-Six-Foot Tall Needle Sculpture Rises Over Arts Quad > EMC2 News > The

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof Energy Forrestal Garage Parking Procedures,

  10. Opportunities and obstacles for US investors in Moscow : office market comparative return study

    E-Print Network [OSTI]

    Stolyarik, Alexander V., 1974-

    2003-01-01T23:59:59.000Z

    Moscow in recent years has seen significant changes in the amount of investment grade office space. In the period before the financial crisis of 1998, in which Russia defaulted on its debt and the ruble was drastically ...

  11. Brownfields redevelopment in rural Massachusetts : understanding the obstacles & identifying opportunities for success

    E-Print Network [OSTI]

    Gallant, Darlene E. (Darlene Elizabeth), 1978-

    2004-01-01T23:59:59.000Z

    Remediating and redeveloping contaminated properties represents a mounting national concern. Commonly referred to as brownfields, these contaminated and often vacant or underused, properties present significant environmental ...

  12. Pair interaction lattice gas simulations: Flow past obstacles in two and three dimensions

    SciTech Connect (OSTI)

    Vogeler, A.; Wolf-Gladrow, D.A. (Alfred-Wegener-Institute for Polar and Marine Research, Bremerhaven (Germany))

    1993-04-01T23:59:59.000Z

    Apart from the FCHC (face-centered hypercube), Nasilowski's pair interaction lattice gas (PI) is the only known lattice gas automaton for three-dimensional hydrodynamic simulations. Unfortunately, the viscosity of PI is not isotropic. In order to determine the degree anisotropy, the authors derive fluid dynamic equations for the regime of compressible viscid flow. From relaxation measurements of waves propagating in various directions they compute the physically relevant dissipation coefficients and compare their results with theoretical predictions. Although PI shows a high degree of anisotropy, they define the mean value of the dissipation tensor as effective shear viscosity. Using this value of v[sub eff][sup 2D] = 0.35, two-dimensional simulations of flow past a cylinder yield drag coefficients in quantitative agreement with wind tunnel measurements over a range of Reynolds numbers of 5-50. Three-dimensional simulations of flow past a sphere yield qualitative agreement with various references. A fit of the results to a semi-empirical curve provides an effective value of v[sub eff][sup 2D] = 0.21 for a range of Reynolds numbers from 0.19 to 40. In order to check for finite-size effects, the authors measured the mean free path [lambda] and computed the Knudsen numbers. They obtained [lambda] [approx]1 lattice unit, corresponding to Kn = 0.01 (2D) and Kn = 0.1 (3D). They found no significant finite-size effects. 44 refs., 10 figs.

  13. Dislocation climb strengthening in systems with immobile obstacles: Three-dimensional level-set simulation study

    E-Print Network [OSTI]

    Chu, Kevin T.

    of High Performance Computing, Singapore, Singapore 5 Department of Materials Science and Engineering

  14. The effects of obstacle geometry on jet mixing in releases of silane

    E-Print Network [OSTI]

    Sposato, Christina F

    2000-01-01T23:59:59.000Z

    of the Realizable k-s Model and VW Model with Experimental Data and Data Fit for a Turbulent Free Jet. . . . . , . . . . . . . . 29 Problem Description for a Plate-Impinging Jet. . . Sample Grid for a Plate-Impinging Jet. . Close up of Grid near the Jet Axis.../Air Mixture at L/Do = 100. . . . . . 40 14 Explosive Volume for a Silane/Air Mixture at L/Dp = 150. . . . . . . 40 15 Explosive Volume for a Silane/Air Mixture at L/Dc = 250. . . . . . . 41 FIGURE Page 16 Explosive Volume for a Silane/Air Mixture at L...

  15. Field descriptions for a developing laminar tube flow with and without a concentrically located spherical obstacle 

    E-Print Network [OSTI]

    Mikkelsen, Clark Douglas

    1972-01-01T23:59:59.000Z

    for the steady, isothermal, originally Poiseuillean flow of an incompressible, Newtonian fluid around a rigid sphere fixed on the axis of an infinitely-long, circular cylinder. Similarities in the flow fields of Cases 1 ~ 2, and 3 were indicated as were..., vorticity, and velocity fields for the steady, isothermal, originally Poiseuillean flow of an incompressible, Newtonian fluid around a rigid sphere f fixed on the axis of an infinitely-long, circular cylinder. t The above definitions for Case 1, 2, and 3...

  16. Optimal Longitudinal Control Planning with Moving Obstacles Jeff Johnson and Kris Hauser

    E-Print Network [OSTI]

    Hauser, Kris

    . INTRODUCTION The Federal Highway Administration in the United States notes that the frequency of automobile application to a simulated urban intersection involving pedestrians, bicyclists, and automobiles, as well is a challenging prob- lem with a long history. In one class of problems, the vehicle has

  17. Experimental Study of Curvature-based Control Laws for Obstacle Avoidance

    E-Print Network [OSTI]

    Zhang, Fumin

    , krishna}@isr.umd.edu Abstract-- A novel curvature-based steering control law is introduced to produce- thermore, with appropriate dynamic model, the algorithm produces an explicit control law for the robot, a recent development in this category is to keep the robot moving at a constant speed with steering control

  18. Saving Energy in Industrial Compressed Air Systems: Issues and Obstacles in DSM Program Design

    E-Print Network [OSTI]

    Trojanowski, D.; Parfomak, P.

    contained compressed air systems.(I) Air compressors are generally driven by electric motors, often in large sizes and often operating continuously throughout the day. As a result, compressors can account for a substantial fraction of the electricity... consumption and peak demand in a given facility. A study by North Carolina A&T University found that air compressors accounted for as much as 49 % of base energy consumption, and up to 58% of peak electrical demand, in the facilities they audited.(2...

  19. Calculation of unsteady turbulent flow around obstacles using the large eddy simulation turbulence model

    E-Print Network [OSTI]

    Helton, Donald McLean

    2002-01-01T23:59:59.000Z

    The premise of the work presented here is to use a common analytical tool, Computational Fluid Dynamics (CFD), along with a prevalent turbulence model, Large Eddy Simulation (LES), to study the flow past rectangular cylinders. In an attempt to use...

  20. NEAR-FIELD IMAGING OF OBSTACLES Peijun Li and Yuliang Wang

    E-Print Network [OSTI]

    2014-06-16T23:59:59.000Z

    In far-field imaging, data is measured at a distance which is a few wavelength or longer away ...... Lastly we examine the effect of the base radius a. In view of.

  1. Obstacles in pursuing teacher certification of paraprofessional employees in a Texas urban school district 

    E-Print Network [OSTI]

    Marz, Carrie Oden

    2006-08-16T23:59:59.000Z

    School districts across the country are faced with teacher shortages in critical need areas such as special education and bilingual education. Further complicating this shortage is the movement to augment the existing ...

  2. Elastic-wave identification of penetrable obstacles using shape-material sensitivity framework

    E-Print Network [OSTI]

    Guzina, Bojan

    in general has been the subject of intensive mathematical and computational research [40,26,13,16], only Palaiseau Cedex, France b Department of Civil Engineering, University of Minnesota, Minneapolis, MN 55455-material sensitivity Elastodynamics Identification Inclusion Boundary element method Constrained optimization a b s t r

  3. Obstacles in pursuing teacher certification of paraprofessional employees in a Texas urban school district

    E-Print Network [OSTI]

    Marz, Carrie Oden

    2006-08-16T23:59:59.000Z

    teachers in order to more closely reflect the changing demographics of the student population. Many states/districts have turned to alternative routes to teaching certification as the answer to expedite the recruitment of teachers. A largely untapped...

  4. Study of the Effects of Obstacles in Liquefied Natural Gas (LNG) Vapor Dispersion using CFD Modeling

    E-Print Network [OSTI]

    Ruiz Vasquez, Roberto

    2012-10-19T23:59:59.000Z

    The evaluation of the potential hazards related with the operation of an LNG terminal includes possible release scenarios with the consequent flammable vapor dispersion within the facility; therefore, it is important to know the behavior...

  5. Proposed roadmap for overcoming legal and financial obstacles to carbon capture and sequestration

    SciTech Connect (OSTI)

    Jacobs, Wendy (Harvard Environmental Law and Policy, Cambridge, MA (US)); Chohen, Leah; Kostakidis-Lianos, Leah; Rundell, Sara (Harvard Law School, Cambridge, MA (US))

    2009-03-01T23:59:59.000Z

    Many existing proposals either lack sufficient concreteness to make carbon capture and geological sequestration (CCGS) operational or fail to focus on a comprehensive, long term framework for its regulation, thus failing to account adequately for the urgency of the issue, the need to develop immediate experience with large scale demonstration projects, or the financial and other incentives required to launch early demonstration projects. We aim to help fill this void by proposing a roadmap to commercial deployment of CCGS in the United States.This roadmap focuses on the legal and financial incentives necessary for rapid demonstration of geological sequestration in the absence of national restrictions on CO2 emissions. It weaves together existing federal programs and financing opportunities into a set of recommendations for achieving commercial viability of geological sequestration.

  6. A remote lab for multi-robot experiments with virtual obstacles

    E-Print Network [OSTI]

    Giannitrapani, Antonello

    the advantages of a real laboratory, remote labs make available to students a number of physical processes of available resources. Over the last decade, a remote lab focused on robotics and control systems curricula (ACT) puts a number of different teaching experiences at users' disposal, ranging from basic electric

  7. More than a “Subspecies of American Literature”: Obstacles toward a Transnational Mormon Novel

    E-Print Network [OSTI]

    Hales, Scott

    2015-01-01T23:59:59.000Z

    Margaret Blair. Salvador. Salt Lake City: Aspen Books, 1993.Salvador (Salt Lake City: Aspen Books, 1993), 32. Robert

  8. A survey of David Lewis's theory of counterfactuals: resolved difficulties and resilient obstacles

    E-Print Network [OSTI]

    Botham, Thad M

    1999-01-01T23:59:59.000Z

    David Lewis [1973b] offers a possible worlds approach to a theory of counterfactuals. He attempts to specify necessary and sufficient conditions according to which a given counterfactual is true or false. My profit surveys Lewis's theory...

  9. Removing Obstacles in Neuroscience Drug Discovery: The Future Path for Animal Models

    E-Print Network [OSTI]

    Kalueff, Allan V.

    to ensure that basic science knowledge gained from improved animal models with good predictive and construct patients as quickly as possible. Neuropsychopharmacology Reviews (2009) 34, 74­89; doi:10.1038/npp.2008

  10. A Path Planning Strategy for Kinematically Redundant Manipulators Anticipating Joint Failures in the Presence of Obstacles

    E-Print Network [OSTI]

    Maciejewski, Anthony A.

    's reliability. However, robot failures are not uncommon. It has been estimated that 28.7% of industrial robots that over 60% of industrial robots had a mean-time-between-failure of less than 500 hours [7]. A number

  11. Advancing TOD in Boston's suburbs : advantages and obstacles in the entitlement process

    E-Print Network [OSTI]

    Simonson, Kristin (Kristin Andrea)

    2011-01-01T23:59:59.000Z

    This thesis is an inquiry into the feasibility of creating new compact, mixed-use transit-oriented development (TOD) within existing suburbs. I have focused on the entitlement phase of projects, during which land is rezoned, ...

  12. Airports and Bicycles: what are the obstacles and incentives for operators 1 to improve bicycle access?

    E-Print Network [OSTI]

    Orrick, Phyllis; Frick, Karen Trapenberg

    2013-01-01T23:59:59.000Z

    43. South Coast Air Quality Management District. SCAQMDunder South Coast Air Quality Management District (SCAQMD)air quality requirements(8). BOS travel demand management

  13. On beyond the standard model for high explosives: challenges & obstacles to surmount

    SciTech Connect (OSTI)

    Menikoff, Ralph Ds [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    Plastic-bonded explosives (PBX) are heterogeneous materials. Nevertheless, current explosive models treat them as homogeneous materials. To compensate, an empirically determined effective burn rate is used in place of a chemical reaction rate. A significant limitation of these models is that different burn parameters are needed for applications in different regimes; for example, shock initiation of a PBX at different initial temperatures or different initial densities. This is due to temperature fluctuations generated when a heterogeneous material is shock compressed. Localized regions of high temperatures are called hot spots. They dominate the reaction for shock initiation. The understanding of hot spot generation and their subsequent evolution has been limited by the inability to measure transients on small spatial ({approx} 1 {micro}m) and small temporal ({approx} 1 ns) scales in the harsh environment of a detonation. With the advances in computing power, it is natural to try and gain an understanding of hot-spot initiation with numerical experiments based on meso-scale simulations that resolve material heterogeneities and utilize realistic chemical reaction rates. However, to capture the underlying physics correctly, such high resolution simulations will require more than fast computers with a large amount of memory. Here we discuss some of the issues that need to be addressed. These include dissipative mechanisms that generate hot spots, accurate thermal propceties for the equations of state of the reactants and products, and controlling numerical entropy error from shock impedance mismatches at material interfaces. The later can generate artificial hot spots and lead to premature reaction. Eliminating numerical hot spots is critical for shock initiation simulations due to the positive feedback between the energy release from reaction and the hydrodynamic flow.

  14. NEAR-FIELD IMAGING OF OBSTACLES Peijun Li and Yuliang Wang

    E-Print Network [OSTI]

    2015-01-15T23:59:59.000Z

    linearized by dropping the higher order terms in the power series expansion. ... the measurement data is simulated by solving the direct problem by using a derived ..... The following theorem shows that it is true, at least when h is sufficiently.

  15. Biomass energy: State of the technology present obstacles and future potential

    SciTech Connect (OSTI)

    Dobson, L.

    1993-06-23T23:59:59.000Z

    The prevailing image of wood and waste burning as dirty and environmentally harmful is no longer valid. The use of biomass combustion for energy can solve many of our nation`s problems. Wood and other biomass residues that are now causing expensive disposal problems can be burned as cleanly and efficiently as natural gas, and at a fraction of the cost. New breakthroughs in integrated waste-to-energy systems, from fuel handling, combustion technology and control systems to heat transfer and power generation, have dramatically improved system costs, efficiencies, cleanliness of emissions, maintenance-free operation, and end-use applications. Increasing costs for fossil fuels and for waste disposal strict environmental regulations and changing political priorities have changed the economics and rules of the energy game. This report will describe the new rules, new playing fields and key players, in the hope that those who make our nation`s energy policy and those who play in the energy field will take biomass seriously and promote its use.

  16. Turbulent boundary layers interacting with groups of obstacles Project Staff Principal investigator: Dr Costantino Manes

    E-Print Network [OSTI]

    Sóbester, András

    (wind or marine) can generate, estimating carbon dioxide exchange between forests and the atmosphere-Dimensional (2-D) flow, where mean turbulent properties are uniform (or almost uniform) along one direction

  17. The parking policy and smart growth disconnect : obstacles to establishing and implementing smart growth parking policy

    E-Print Network [OSTI]

    Richardson, Heather Eileen Seyfang

    2005-01-01T23:59:59.000Z

    Urban areas are plagued by congestion, economic inequality, and inefficient land use that result from highway and single family housing subsidies, segregated land uses, and many other government policies established over ...

  18. Size based separation of submicron nonmagnetic particles through magnetophoresis in structured obstacle arrays

    E-Print Network [OSTI]

    Annavarapu, V. N. Ravikanth (Venkata Nagandra Ravikanth)

    2010-01-01T23:59:59.000Z

    The focus of this work was on developing a novel scalable size based separation technology for nonmagnetic particles in the submicron size range utilizing magnetophoretic forces. When a nonmagnetic particle is immersed in ...

  19. An Integrated Framework for Obstacle Mapping with See-Through Capabilities using Laser and Wireless

    E-Print Network [OSTI]

    Liebling, Michael

    of the environment (the parts that can be sensed directly by the laser scanners) using occupancy grid mapping/object map can be a 2D (or 3D) grid map of the environment, where we have zeros at locations where, for instance, occupancy grid mapping approaches [1], [5] have been proposed to build a grid map

  20. First-Generation Risk Profiles Help Predict CO2 Storage Site Obstacles |

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently20,000 Russian NuclearandJunetrackEllen|JulyR--FOIADepartmentJulyDeputyUpdatesDepartment

  1. Study of the Effects of Obstacles in Liquefied Natural Gas (LNG) Vapor Dispersion using CFD Modeling 

    E-Print Network [OSTI]

    Ruiz Vasquez, Roberto

    2012-10-19T23:59:59.000Z

    The evaluation of the potential hazards related with the operation of an LNG terminal includes possible release scenarios with the consequent flammable vapor dispersion within the facility; therefore, it is important to ...

  2. Movement reproduction and obstacle avoidance with dynamic movement primitives and potential fields

    E-Print Network [OSTI]

    Schaal, Stefan

    demonstration [5], [6]. A human movement is recorded and later reproduced by a robot. Challenges that arise@usc.edu, sschaal@usc.edu Abstract--Robots in a human environment need to be compli- ant. This compliance requires the abilities of our approach in simulations and with an anthropomorphic robot arm. I. INTRODUCTION Humans can

  3. Generalized Velocity Obstacles David Wilkie Jur van den Berg Dinesh Manocha

    E-Print Network [OSTI]

    North Carolina at Chapel Hill, University of

    robot- human interactions, such as robotic wheelchairs [18]. In many of these applications, the robot, but it may not capture the movement of car-like robots well, which can only move, at any instant the problem of real-time navigation in dynamic environments for car-like robots. We present an approach

  4. First-Generation Risk Profiles Help Predict CO2 Storage Site Obstacles |

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T,OfficeEnd ofEvaluations inCommittee |a Career in92 of 864 5.0First

  5. Studies of Nearby Blazars with Milagro D. A. Williams for the Milagro Collaboration1

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Milagro on new unidentified sources [2], gamma-ray bursts [3], galactic plane emission [4], and a search tubes (PMTs) to monitor the northern sky for astrophysical gamma-ray emission near 1 TeV. It is locatedV flaring behavior associated with AGN, even during daytime transits. The incident direction of gamma-ray

  6. A HUBBLE SPACE TELESCOPE SURVEY OF THE MID-ULTRAVIOLET MORPHOLOGY OF NEARBY GALAXIES1

    E-Print Network [OSTI]

    Hibbard, John

    . Eskridge2 Department of Physics and Astronomy, Minnesota State University, Mankato, MN 56003 Jay A. Frogel2 of Astronomy, University of Virginia, P.O. Box 3818, Charlottesville, VA 22903-0818 Received 2001 July 2

  7. Very Small Array observations of the Sunyaev-Zel'dovich effect in nearby galaxy clusters

    E-Print Network [OSTI]

    Katy Lancaster; Ricardo Genova-Santos; Nelson Falcon; Keith Grainge; Carlos Gutierrez; Ruediger Kneissl; Phil Marshall; Guy Pooley; Rafael Rebolo; Jose-Alberto Rubino-Martin; Richard D. E. Saunders; Elizabeth Waldram; Robert A. Watson

    2004-12-02T23:59:59.000Z

    We present VSA observations (~34GHz) on scales ~20 arcmin towards a complete, X-ray-flux-limited sample of seven clusters at redshift z<0.1. Four have significant SZ detections in the presence of CMB primordial anisotropy. We use a bayesian MCMC method for inference from the VSA data, with X-ray priors on cluster positions and temperatures, and radio priors on sources. We make assumptions of beta-model gas distributions and of hydrostatic equilibrium, to evaluate probability densities for the gas mass and total mass out to r_200. Our combined estimate of the gas fraction is 0.08^{+0.06}_{-0.04}h^{-1} The random errors are poor (note that the errors are higher than would have been obtained with the usual chi-squared method) but the control of bias is good. We have described the MCMC analysis method specifically in terms of SZ but hope the description will be of more general use. We find that the effects of primordial CMB contamination tend to be similar in the estimates of both the gas mass and total mass over our narrow range of angular scales, so that there is little effect of primordials on the gas fraction determination. Using our total mass estimates we find a normalisation of the mass-temperature relation based on the profiles from the VSA cluster pressure maps that is in good agreement with recent M-T determinations from X-ray cluster measurements.

  8. Literature Review of Unconsolidated Sediment in San Francisco Bay and Nearby Pacific Ocean Coast

    E-Print Network [OSTI]

    Keller, Barry R.

    2009-01-01T23:59:59.000Z

    debris, blasting of rocks, dredging of navigation channels,as channel mainte- nance dredging and sand mining. Recently,hazards removal, channel dredging, and sand mining. Most of

  9. The open cluster NGC 6520 and the nearby dark molecular cloud Barnard 86

    E-Print Network [OSTI]

    Giovanni Carraro; Rene Mendez; Jorge May; Diego Mardones

    2005-04-20T23:59:59.000Z

    Wide field BVI photometry and $^{12}$CO(1$\\to$0) observations are presen ted in the region of the open cluster NGC 6520 and the dark molecular cloud Barnard~86. From the analysis of the optical data we find that the cluster is rather compact, with a radius of 1.0$\\pm$0.5 arcmin, smaller than previous estimates. The cluster age is 150$\\pm$50 Myr and the reddening E$_{B-V}$=0.42$\\pm$0.10. The distance from the Sun is estimated to be 1900$\\pm$100 pc, and it is larger than previous estimates. We finally derive basic properties of the dark nebula Barnard 86 on the assumption that it lies at the same distance of the cluster.

  10. Cosmological constraints from the virial mass function of nearby galaxy groups and clusters

    E-Print Network [OSTI]

    Hill, James Colin

    2008-01-01T23:59:59.000Z

    In this thesis, I present a new determination of the cluster mass function in a volume ~107 h-03 70 Mpc3 using the ROSAT-2MASS-FAST Group Survey (R2FGS). R2FGS is an X-ray-selected sample of systems from the ROSAT All-Sky ...

  11. The Magnificent Seven: Nearby Isolated Neutron Stars with strong Magnetic Fields

    E-Print Network [OSTI]

    F. Haberl

    2005-10-17T23:59:59.000Z

    Although the true origin of the broad absorption lines in X-ray spectra of thermal isolated neutron stars is not clear yet, our current knowledge about the "magnificent seven" strongly suggests that they are highly magnetized ($10^{13} - 10^{14}$ G), slowly rotating cooling neutron stars. Further timing studies would be very useful to obtain more independent estimates of the magnetic field strength (as they currently only exist from RX J0720.4-3125).

  12. Cosmic rays and the magnetic field of the nearby starburst galaxy NGC 253

    E-Print Network [OSTI]

    V. Heesen; R. -J. Dettmar; M. Krause; R. Beck

    2008-01-23T23:59:59.000Z

    Using radio polarimetry we study the connection between the transport of cosmic rays (CR's), the three-dimensional magnetic field structure, and features of other ISM phases in the halo of NGC 253. We present a new sensitive radio continuum map of NGC 253 obtained from combined VLA and Effelsberg observations at lambda 6.2 cm. We find a prominent radio halo with a scaleheight of the thick radio disk of 1.7 kpc. The linear dependence between the local scaleheight of the vertical continuum emission and the cosmic ray electron (CRE) lifetime requires a vertical CR bulk speed of 270 km s^-1. The magnetic field structure of NGC 253 resembles an ``X''-shaped configuration where the orientation of the large-scale magnetic field is plane-parallel only in the inner regions of the disk and at small distances from the galactic midplane. At larger galactocentric radii and further away from the midplane the vertical component becomes important. This is most clearly visible at the location of the ``radio spur'' southeast of the nucleus, where the magnetic field orientation is almost vertical. We made a simple model for the dominant toroidal (r,phi) magnetic field component using a spiral magnetic field with prescribed inclination and pitch angle. The residual poloidal (r,phi,z) magnetic field component which was revealed by subtracting the model from the observations shows a distinct ``X''-shaped magnetic field orientation centered on the nucleus. The orientation angle of the poloidal magnetic field is consistent with a magnetic field transport described by the superposition of the vertical CR bulk speed and the rotation velocity. Hence, we propose a disk wind which transports cosmic rays, magnetic field, and (partially) ionized gas from the disk into the halo.

  13. A 3D Search for Companions to 12 Nearby M-Dwarfs

    E-Print Network [OSTI]

    Davison, Cassy L; Henry, Todd J; Riedel, Adric R; Jao, Wei-Chun; Bailey, John I; Quinn, Samuel N; Cantrell, Justin R; Subasavage, John P; Winters, Jen G

    2015-01-01T23:59:59.000Z

    We present a carefully vetted equatorial ($\\pm$ 30$^\\circ$ Decl.) sample of all known single (within 4'') mid M-dwarfs (M2.5V-M8.0V) extending out to 10 pc; their proximity and low masses make them ideal targets for planet searches. For this sample of 58 stars, we provide V$_J$, R$_{KC}$, I$_{KC}$ photometry, new low dispersion optical ($6000 - 9000$\\AA) spectra from which uniform spectral types are determined, multi-epoch H$\\alpha$ equivalent widths, and gravity sensitive $Na\\,I$ indices. For 12 of these 58 stars, strict limits are placed on the presence of stellar and sub-stellar companions, based on a pioneering program described here that utilizes precise infrared radial velocities and optical astrometric measurements in an effort to search for Jupiter-mass, brown dwarf and stellar-mass companions. Our infrared radial velocity precision using CSHELL at NASA's IRTF is $\\sim$90 m s$^{-1}$ over timescales from 13 days to 5 years. With our spectroscopic results the mean companion masses that we rule out of ex...

  14. Cosmic rays and the magnetic field of the nearby starburst galaxy NGC 253

    E-Print Network [OSTI]

    Heesen, V; Krause, M; Beck, R

    2008-01-01T23:59:59.000Z

    Using radio polarimetry we study the connection between the transport of cosmic rays (CR's), the three-dimensional magnetic field structure, and features of other ISM phases in the halo of NGC 253. We present a new sensitive radio continuum map of NGC 253 obtained from combined VLA and Effelsberg observations at lambda 6.2 cm. We find a prominent radio halo with a scaleheight of the thick radio disk of 1.7 kpc. The linear dependence between the local scaleheight of the vertical continuum emission and the cosmic ray electron (CRE) lifetime requires a vertical CR bulk speed of 270 km s^-1. The magnetic field structure of NGC 253 resembles an ``X''-shaped configuration where the orientation of the large-scale magnetic field is plane-parallel only in the inner regions of the disk and at small distances from the galactic midplane. At larger galactocentric radii and further away from the midplane the vertical component becomes important. This is most clearly visible at the location of the ``radio spur'' southeast o...

  15. V405 Peg (RBS 1955): A Nearby, Low-Luminosity Cataclysmic Binary

    E-Print Network [OSTI]

    Thorstensen, J R; Schwope, A D; Staude, A; Vogel, J; Krumpe, M; Kohnert, J; Gomez-Moran, A Nebot

    2009-01-01T23:59:59.000Z

    (Abridged). The cataclysmic binary V405 Peg, originally discovered as ROSAT Bright Source (RBS) 1955 (= 1RXS J230949.6+213523), shows a strong contribution from a late-type secondary star in its optical spectrum, which led Schwope et al. to suggest it to be among the nearest cataclysmic binaries. We present extensive optical observations of V405 Peg. Time-series spectroscopy shows the orbital period, Porb, to be 0.1776469(7) d (= 4.2635 hr), or 5.629 cycle/d. We classify the secondary as M3 - M4.5. Astrometry with the MDM 2.4m telescope gives a parallax 7.2 +- 1.1 milli-arcsec, and a relative proper motion of 58 mas/yr. Our best estimate of the distance yields d = 149 (+26, -20) pc. The secondary stars's radial velocity has K2 = 92 +- 3 km/s, indicating a fairly low orbital inclination if the masses are typical. Extensive I-band time-series observations in the show the system varying between a minimum brightness level of I = 14.14 and states of enhanced activity about 0.2 mag brighter. While the low-state sho...

  16. III. High-Resolution Imaging of Nearby M dwarfs V. J. S. Bjar1,2

    E-Print Network [OSTI]

    Complutense de Madrid, Universidad

    la Universidad de La Laguna, 3Centro de Astrobiología, 4Max-Planck-Institut für Astronomie · 5. Flux contribution and variations induced by companions at different separations. Red, blue and green

  17. Exploration of the environments of nearby stars with the NICMOS coronagraph instrumental performance considerations

    E-Print Network [OSTI]

    Schneider, Glenn

    pupil­plane mask (maintained at ~100K), with radial structures co­aligned with the HST secondary mirror. The coronagraph is comprised of two optical elements. The camera 2 field divider mirror, upon which the HST f/24. Keywords: Infrared, Coronagraphy, Hubble Space Telescope, Brown Dwarfs, Extra­Solar Planets 1. SCIENTIFIC

  18. Deterministic knowledge about nearby nodes in a mobile one dimensional environment

    E-Print Network [OSTI]

    Subramanian, Sivaramakrishnan

    2009-05-15T23:59:59.000Z

    > > > 8 9 > > 11 Br oa dc as tS lot s 12 13 > > > 14 > > 16 Fig. 6. The Final Broadcast Schedule for m = 5 When both m and pi are odd, the alternation starts with the segment class to the right... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 8 List of Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 9 Theorem 2 - Case 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 10 Theorem 2 - Case 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 11 pi+1...

  19. Magnetic fields in the nearby spiral galaxy IC 342: A multifrequency radio polarization study

    E-Print Network [OSTI]

    Beck, Rainer

    2015-01-01T23:59:59.000Z

    The total and polarized radio continuum emission of IC 342 was observed in four wavelength bands with the Effelsberg and VLA telescopes. The frequency-dependent radial scalelength of the diffuse radio synchrotron disk is indicative of propagation of cosmic-ray electrons via the streaming instability. The equipartition strength of the total magnetic field is typically 15 muG, that of the ordered field 5 muG. Faraday rotation reveals an underlying regular field of only about 0.5 muG strength with an axisymmetric spiral pattern, signature of a mean-field dynamo, and an about 10x stronger field that fluctuates on scales of a few 100 pc. The magnetic field around the bar in the central region of IC 342 resembles that of large barred galaxies; its regular spiral field is directed outwards, opposite to that in the disk. The polarized emission in the disk is concentrated in: (1) a narrow arm of about 300 pc width, displaced inwards with respect to the eastern arm by about 200 pc, indicating magnetic fields compressed...

  20. Luminous AGB stars in nearby galaxies. A study using Virtual Observatory tools

    E-Print Network [OSTI]

    P. Tsalmantza; E. Kontizas; L. Cambresy; F. Genova; A. Dapergolas; M. Kontizas

    2005-10-13T23:59:59.000Z

    Aims. This study focuses on very luminous Mbol1.5 mag and H-Ks>0.4 mag in the LMC, SMC, M31, and M33 from 2MASS data. Methods.The data were taken from the 2MASS All-Sky Point Source catalogue archive. We used Virtual Observatory tools and took advantage of its capabilities at various stages in the analysis. Results. It is well known that stars with the colors we selected correspond mainly to carbon stars. Although the most luminous AGBs detected here contain a large number of carbon stars,they are not included in existing catalogues produced from data in the optical domain, where they are not visible since they are dust-enshrouded. A comparison of the AGB stars detected with combined near and mid-infrared data from MSX and 2MASS in the LMC shows that 10% of the bright AGB stars are bright carbon stars never detected before and that the other 50% are OH/IR oxygen rich stars, whereas the 40% that remain were not cross-matched. Conclusions. The catalogues of the most luminous AGB stars compiled here are an important complement to existing data. In the LMC, these bright AGB stars are centrally located, whereas they are concentrated in an active star-formation ring in M31. In the SMC and M33, there are not enough of them to draw definite conclusions, although they tend to be centrally located. Their luminosity functions are similar for the four galaxies we studied.

  1. A possible optical counterpart to the old nearby pulsar J0108-1431

    E-Print Network [OSTI]

    R. P. Mignani; G. G. Pavlov; O. Kargaltsev

    2008-05-16T23:59:59.000Z

    The multi-wavelength study of old (>100 Myr) radio pulsars holds the key to understanding the long-term evolution of neutron stars, including the advanced stages of neutron star cooling and the evolution of the magnetosphere. Optical/UV observations are particularly useful for such studies because they allow one to explore both thermal and non-thermal emission processes. In particular, studying the optical/UV emission constrains temperature of the bulk of the neutron star surface, too cold to be measured in X-ray observations.Aim of this work is to identify the optical counterpart of the very old (166 Myr) radio pulsar J0108-1431. We have re-analyzed our original VLT observations (Mignani et al. 2003), where a very faint object was tentatively detected close to the radio position, near the edge of a field galaxy. We found that the backward extrapolation of the PSR J0108-1431 proper motion recently measured by CHANDRA(Pavlov et al. 2008) nicely fits the position of this object. Based on that, we propose it as a viable candidate for the optical counterpart to PSR J0108-1431. The object fluxes (U =26.4+/-0.3; B =27.9; V >27.8) are consistent with a thermal spectrum with a brightness temperature of 9X10^4 K (for R = 13 km at a distance of 130 pc), emitted from the bulk of the neutron star surface. New optical observations are required to confirm the optical identification of PSR J0108-1431 and measure its spectrum.

  2. A possible optical counterpart to the old nearby pulsar J0108-1431

    E-Print Network [OSTI]

    Mignani, R P; Kargaltsev, O

    2008-01-01T23:59:59.000Z

    The multi-wavelength study of old (>100 Myr) radio pulsars holds the key to understanding the long-term evolution of neutron stars, including the advanced stages of neutron star cooling and the evolution of the magnetosphere. Optical/UV observations are particularly useful for such studies because they allow one to explore both thermal and non-thermal emission processes. In particular, studying the optical/UV emission constrains temperature of the bulk of the neutron star surface, too cold to be measured in X-ray observations.Aim of this work is to identify the optical counterpart of the very old (166 Myr) radio pulsar J0108-1431. We have re-analyzed our original VLT observations (Mignani et al. 2003), where a very faint object was tentatively detected close to the radio position, near the edge of a field galaxy. We found that the backward extrapolation of the PSR J0108-1431 proper motion recently measured by CHANDRA(Pavlov et al. 2008) nicely fits the position of this object. Based on that, we propose it as ...

  3. A Search for Extraplanar Dust in Nearby Edge-On Spirals

    E-Print Network [OSTI]

    J. Christopher Howk; Blair D. Savage

    1999-02-04T23:59:59.000Z

    We present high resolution BV images of 12 edge-on spiral galaxies observed with the WIYN 3.5-m telescope. These images were obtained to search for extraplanar (|z| > 0.4 kpc) absorbing dust structures similar to those previously found in NGC 891 (Howk & Savage 1997). Our imaged galaxies include a sample of seven massive L_*-like spiral galaxies within D 87 deg from the plane of the sky. We find that five of these seven systems show extraplanar dust, visible as highly-structured absorbing clouds against the background stellar light of the galaxies. The more prominent structures are estimated to have associated gas masses >10^5 M_sun; the implied potential energies are > 10^(52) ergs. All of the galaxies in our sample that show detectable halpha emission at large z also show extraplanar dust structures. None of those galaxies for which extraplanar halpha searches were negative show evidence for extensive high-z dust. The existence of extraplanar dust is a common property of massive spiral galaxies. We discuss several mechanisms for shaping the observed dust features, emphasizing the possibility that these dusty clouds represent the dense phase of a multiphase medium at high-z in spiral galaxies. The correlation between high-z dust and extraplanar Halpha emission may simply suggest that both trace the high-z interstellar medium in its various forms (or phases), the existence of which may ultimately be driven by vigorous star formation in the underlying disk. (Abstract abridged)

  4. Extraplanar Dust and Star Formation in Nearby Edge-On Galaxies

    E-Print Network [OSTI]

    J. Christopher Howk; Blair D. Savage

    1998-10-27T23:59:59.000Z

    We present high-resolution ( 0.5 - 2.0. If Milky Way gas-to-dust relationships are appropriate, then these structures have gaseous column densities N_H > 10(21) cm(-2), with very large masses (>10(5) - 10(6) solar masses) and gravitational potential energies (> 10(51) - 10(52) ergs relative to z=0). The estimated column densities suggest molecular gas may be present, and with the estimated masses allows for the possibility of star formation in these dusty clouds. Recent star formation is the likely cause of the discrete H II regions, in some cases associated with relatively blue continuum sources, observed at heights 0.6 < |z| < 0.8 kpc above the disks of these galaxies. The presence of early-type stars at high-z in these galaxies may be related to the extraplanar dust structures seen in our images.

  5. ALFALFA DISCOVERY OF THE NEARBY GAS-RICH DWARF GALAXY LEO P. I. H I OBSERVATIONS

    SciTech Connect (OSTI)

    Giovanelli, Riccardo; Haynes, Martha P.; Adams, Elizabeth A. K. [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States); Cannon, John M.; Bernstein-Cooper, Elijah Z. [Department of Physics and Astronomy, Macalester College, Saint Paul, MN 55105 (United States); Rhode, Katherine L.; Salzer, John J. [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States); Skillman, Evan D.; McQuinn, Kristen B. W., E-mail: riccardo@astro.cornell.edu, E-mail: haynes@astro.cornell.edu, E-mail: betsey@astro.cornell.edu, E-mail: jcannon@macalester.edu, E-mail: ebernste@macalester.edu, E-mail: rhode@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: skillman@astro.umn.edu, E-mail: kmcquinn@astro.umn.edu [Minnesota Institute for Astrophysics, University of Minnesota, Minneapolis, MN 55455 (United States)

    2013-07-01T23:59:59.000Z

    The discovery of a previously unknown 21 cm H I line source identified as an ultra-compact high velocity cloud in the ALFALFA survey is reported. The H I detection is barely resolved by the Arecibo 305 m telescope {approx}4' beam and has a narrow H I linewidth (half-power full width of 24 km s{sup -1}). Further H I observations at Arecibo and with the Very Large Array corroborate the ALFALFA H I detection, provide an estimate of the H I radius, {approx}1' at the 5 Multiplication-Sign 10{sup 19} cm{sup -2} isophote, and show the cloud to exhibit a velocity field which, if interpreted as disk rotation, has an amplitude of {approx_equal}9.0 {+-} 1.5 km s{sup -1}. In other papers, Rhode et al. show the H I source to have a resolved stellar counterpart and ongoing star forming activity, while Skillman et al. reveal it as having extremely low metallicity: 12 + log (O/H) = 7.16 {+-} 0.04. The H I mass to stellar mass ratio of the object is found to be 2.6. We use the Tully-Fisher template relation in its baryonic form to obtain a distance estimate D{sub Mpc}=1.3{sup +0.9}{sub -0.5}. Additional constraints on the distance are also provided by the optical data of Rhode et al. and McQuinn et al., both indicating a distance in the range of 1.5 to 2.0 Mpc. The three estimates are compatible within their errors. The object appears to be located beyond the dynamical boundaries of, but still in close proximity to the Local Group. Its pristine properties are consistent with the sedate environment of its location. At a nominal distance of 1.75 Mpc, it would have an H I mass of {approx_equal} 1.0 Multiplication-Sign 10{sup 6} M {sub Sun }, a stellar mass of {approx_equal} 3.6 Multiplication-Sign 10{sup 5} M {sub Sun }, and a dynamical mass within the H I radius of {approx_equal} 1.5 Multiplication-Sign 10{sup 7} M {sub Sun }. This discovery supports the idea that optically faint-or altogether dark-low mass halos may be detectable through their non-stellar baryons.

  6. The behavior of Radium-226 in the Mississippi River mixing zone and nearby waters

    E-Print Network [OSTI]

    Moore, Daniel Garman

    1986-01-01T23:59:59.000Z

    ancillary data. Also appreciation is expressed to the members of Dr. Schink's lab, James Orr and Norman Guinasso, for their assistance in the assembly and troubleshooting of the radon trapping and counting system used in this work. Special thanks... Samples. . . Dissolved Radium Extraction. Suspended Sediment Radium-226 Radium-226 Determination. Radon Trapping and Counting System. Counting Cells. . . Radium-226 Counting. RESULTS. Field Results. Radium-226 Plots. August, 1979 ? Low Discharge...

  7. Radio spectral characteristics of the supernova remnant Puppis A and nearby sources

    E-Print Network [OSTI]

    Reynoso, E M

    2015-01-01T23:59:59.000Z

    This paper presents a new study of the spectral index distribution of the supernova remnant (SNR) Puppis A. The nature of field compact sources is also investigated according to the measured spectral indices. This work is based on new observations of Puppis A and its surroundings performed with the Australia Telescope Compact Array in two configurations using the Compact Array Broad-band Backend centered at 1.75 GHz. We find that the global spectral index of Puppis A is -0.563 +/- 0.013. Local variations have been detected, however this global index represents well the bulk of the SNR. At the SE, we found a pattern of parallel strips with a flat spectrum compatible with small-scale filaments, although not correlated in detail. The easternmost filament agrees with the idea that the SN shock front is interacting with an external cloud. There is no evidence of the previously suggested correlation between emissivity and spectral index. A number of compact features are proposed to be evolved clumps of ejecta based...

  8. X-ray observations of neutron stars and black holes in nearby

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    find them · Accretion disks : Gravitational energy of gas is converted to thermal energy L= GM mc2 R.g. Disk-BB to measure BH mass power-laws to distinguish pulsar from BH binaries K M M 102T 41 7

  9. Characterization of a microwave frequency resonator via a nearby quantum dot

    E-Print Network [OSTI]

    Wallraff, Andreas

    and superconducting qubits. The study of the inter- action between the electromagnetic field of such a resonator of a hybrid system consisting of a microwave transmission-line resonator and a lateral quantum dot defined is studied by monitoring the electrical conductance through the quantum dot. The presence of a strong

  10. Literature Review of Unconsolidated Sediment in San Francisco Bay and Nearby Pacific Ocean Coast

    E-Print Network [OSTI]

    Keller, Barry R.

    2009-01-01T23:59:59.000Z

    for construction of Treasure Island in the 1930s. Furtherin 1800. Locally, as at Treasure Island, parts of what was

  11. Automatic Selection of Nearby Web Servers USC TR 98-688

    E-Print Network [OSTI]

    Heidemann, John

    Advanced Re- search Projects Agency (DARPA) through FBI contract #J- FBI-95-185 entitled \\Large Scale

  12. Analysis of perturbed magnetic fields via construction of nearby integrable fields

    E-Print Network [OSTI]

    Hudson, Stuart

    . Dewar Dept. of Theoretical Physics & Plasma Research Laboratory, R.S.Phys.S.E., Australian National

  13. Stellar and Intermediate-Mass Black Holes in the Milky Way and Nearby Galaxies

    SciTech Connect (OSTI)

    Irwin, Jimmy [Department of Physics and Astronomy, University of Alabama, Box 870324, Tuscaloosa, AL 35487-0324 (United States)

    2010-08-09T23:59:59.000Z

    With the advent of high resolution X-ray telescopes, the ability to identify extragalactic black holes has greatly enhanced our understanding of massive compact objects, as we are no longer limited to the rather meager Milky Way black hole population. The greatly increased numbers have opened up opportunities to find new modes of compact object accretion and potentially long-sought evidence for intermediate-mass black holes. In this lecture series, the current state of knowledge of stellar- and intermediate-mass black holes is reviewed, particularly in regards to black hole populations in external galaxies.

  14. Time monitoring of radio jets and magnetospheres in the nearby young stellar cluster R Coronae Australis

    SciTech Connect (OSTI)

    Liu, Hauyu Baobab; Takami, Michihiro; Yan, Chi-Hung; Karr, Jennifer; Chou, Mei-Yin; Ho, Paul T.-P. [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei, 106, Taiwan (China); Galván-Madrid, Roberto; Costigan, Gráinne; Manara, Carlo Felice [European Southern Observatory, Karl-Schwarzschild-Str. 2, D-85748, Garching (Germany); Forbrich, Jan [Department of Astrophysics, University of Vienna, Türkenschanzstraße 17, A-1180, Vienna (Austria); Rodríguez, Luis F. [Centro de Radioastronomía y Astrofísica, UNAM, A.P. 3-72, Xangari, Morelia, 58089 (Mexico); Zhang, Qizhou, E-mail: hyliu@asiaa.sinica.edu.tw [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2014-01-10T23:59:59.000Z

    We report Karl G. Jansky Very Large Array 8-10 GHz (? = 3.0-3.7 cm) monitoring observations toward the young stellar object (YSO) cluster R Coronae Australis (R CrA), taken from 2012 March 15 to 2012 September 12. These observations were planned to measure the radio flux variabilities in timescales from 0.5 hr to several days, to tens of days, and up to ?200 days. We found that among the YSOs detectable in individual epochs, in general, the most reddened objects in the Spitzer observations show the highest mean 3.5 cm Stokes I emission, and the lowest fractional variabilities on <200 day timescales. The brightest radio flux emitters in our observations are the two reddest sources IRS7W and IRS7E. In addition, by comparing our observations with observations taken from 1996 to 1998 and 2005, we found that the radio fluxes of these two sources have increased by a factor of ?1.5. The mean 3.5 cm fluxes of the three Class I/II sources, IRSI, IRS2, and IRS6, appear to be correlated with their accretion rates derived by a previous near-infrared line survey. The weakly accreting Class I/II YSOs, or those in later evolutionary stages, present radio flux variability on <0.5 hr timescales. Some YSOs were detected only during occasional flaring events. The source R CrA went below our detection limit during a few fading events.

  15. High Statistics Study of Nearby Type 1a Supernovae. QUEST Camera Short Term

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School football High School football Fancy footwork at

  16. Age-dependent variation in the biophysical properties of boreal forests

    E-Print Network [OSTI]

    McMillan, Andrew M. S.; Goulden, M. L.

    2008-01-01T23:59:59.000Z

    few senescent jack pine and aspen. Nearly 100% feather moss700 cm tall jack pine and aspen, with significant mortalitywith scattered 500-cm-tall aspen. Many 100–200 cm tall black

  17. Emissions of C6-C8 aromatic compounds in the United States: Constraints from tall tower1 and aircraft measurements2

    E-Print Network [OSTI]

    Mlllet, Dylan B.

    6, 7 5 6 1. Department of Soil, Water, and Climate, University of Minnesota, St. Paul, MN, USA [Ahmadov et al.,18 2014; Jaars et al., 2014; Xue et al., 2014]. These aromatic VOCs (so-called BTEX

  18. Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT): Overview of a wintertime air chemistry field study in the front range urban corridor of Colorado

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    to local emissions from oil and gas activities. Citation:NO x emissions in 2006), oil and gas wells, and largein Denver, and emissions from oil and gas development in the

  19. IIT Delhi launches SmartCaneTM to assist visually impaired to detect above-the-knee obstacles

    E-Print Network [OSTI]

    Banerjee, Subhashis

    manufacturer of medical devices for infant and maternity care is the industrial partner of Smart Delhi, March 30, 2014: The Indian Institute of Technology Delhi's Assistive Technologies Group-level. Utilising modern sensor technology, this device detects obstructions up to a distance of 3 metres

  20. Using Section 111 of the Clean Air Act for Cap-and-Trade of Greenhouse Gas Emissions: Obstacles and Solutions

    E-Print Network [OSTI]

    Enion, Rhead M.

    2012-01-01T23:59:59.000Z

    focused nitro- gen oxide emissions-trading program for largeNSPS program could use emissions trading, including cap-and-regulations that allow emissions trading, to achieve GHG

  1. Experiments of trajectory generation and obstacle avoidance for a UGV David Vissi`ere, Dong Eui Chang, and Nicolas Petit

    E-Print Network [OSTI]

    on a mobile robotic experiment developed at the DGA Laboratoire de Recherche en Balistique et A david.vissiere@dga.defense.gouv.fr D. E. Chang is Assistant Professor in the Department of Applied

  2. I., Generation and measurement of random wave spectra, II., Transmission of random waves past a surface obstacle

    E-Print Network [OSTI]

    Hayden, David Dantagnan

    1985-01-01T23:59:59.000Z

    and Theoretical Narrow-Banded Spectrum with f s 0.80 Hz 7 2 peak 2 3 Comparison of Measured and Theoretical Broad-Banded Spectrum with f a 1 . 2 0 Hz 7 3 peak 24 Comparison of Measured and Theoretical Broad-Banded Spectrum with f 2 0.90 Hz 7 4 peak 25... Comparison of Measured and Theoretical Broad-Banded Spectrum with f a 0.75 Hz, Velocity Control 7 5 peak 26 Comparison of Measured and Theoretical Broad-Banded Spectrum with f ^ = 0.75 Hz, Absorption Control. . . . 76 27 Schematic of Water...

  3. To appear in IEEE Trans. On CAD 1 Abstract--Partial shading is a serious obstacle to the effective

    E-Print Network [OSTI]

    Pedram, Massoud

    utilization of photovoltaic (PV) systems since it can result in a significant degradation in the PV system of a large-scale PV system comprised of 3 PV modules with 60 PV cells per module. Index Terms--Photovoltaic system, partial shading, photovoltaic module reconfiguration, dynamic programming. I. INTRODUCTION UE

  4. Structural foam-core panels in Northwest HUD-code manufactured housing: A preliminary assessment of opportunities and obstacles

    SciTech Connect (OSTI)

    Durfee, D.L.; Lee, A.D.; Onisko, S.A.

    1993-07-01T23:59:59.000Z

    This investigation of structural foam-core panels (foam panels) in manufactured housing was initiated during the Super Good Cents (SGC) program. The SGC program limited allowable glazing area because of the relatively high thermal losses associated with most windows. Due to their superior thermal performance, foam panels appeared to be a viable option to allow increased glazing area without compromising the thermal integrity of the wall. With the inception of the Manufactured-Housing Acquisition Program (MAP), however, the focus of this study has shifted. MAP permits unlimited glazing area if expensive, super-efficient, vinyl-framed, argon-gas-filled, low-emissivity coated windows are installed. Although MAP permits unlimited glazing area, a foam panel wall could allow the use of less expensive windows, larger window area, or less insulation and still provide the required thermal performance for the building. Bonneville contracted with the Pacific Northwest Laboratory (PNL) to investigate the feasibility of using foam panels in HUD-code manufactured housing. This study presents the results from a product and literature search. The potential barriers and benefits to the use of foam panels are determined from a regional survey of the HUD-code manufacturers and foam panel producers.

  5. Analysis of the obstacles to financing geothermal hydrothermal commercialization projects and the government programs designed to remove them

    SciTech Connect (OSTI)

    Not Available

    1981-03-20T23:59:59.000Z

    The risks associated with geothermal hydrothermal commercialization are broken down into five categories: resource risk; technological risk; regulatory risk; investment parity risks; and institutional risk aversion. The impact of each risk upon geothermal financing is assessed. The federal government's programs to provide financial incentives for geothermal development are presented as follows: tax incentives; indirect financial incentives programs; direct grant/cost-sharing programs; and attempts at reducing regulatory risk through the enactment of legal and institutional reforms. (MHR)

  6. Executive summary: legal obstacles and incentives to small-scale hydroelectric development in the six middle atlantic states

    SciTech Connect (OSTI)

    None,

    1980-05-01T23:59:59.000Z

    The executive summary describes the relationship of Federal law and regulation to state law and regulation of small-scale hydroelectric facilities, highlighting important features of the constitutional, statutory, case law, and regulations of each of the six middle atlantic states (Maryland, Delaware, New York, New Jersey, Pennsylvania, and Virginia). Water law, direct and indirect regulation, and financial considerations for each state are presented. A flow diagram of regulation of small dams in each state is also included.

  7. Morphologic and computational fluid dynamic analysis of sand dune-topographic obstacle interactions on Earth and Titan 

    E-Print Network [OSTI]

    Cisneros, Julia

    2014-09-24T23:59:59.000Z

    Earth and Titan have vastly different physical environments, but similar landscapes. Sand dunes, like those found in Earth’s deserts, cover large areas of Titan’s equatorial region and are important records of climate. Titan’s linear dunes...

  8. NREL Overcomes Obstacles in Lignin Valorization (Fact Sheet), NREL Highlights in Research & Development, NREL (National Renewable Energy Laboratory)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparency Visit | National Nuclear 1 NATIONALexaminesDynamic

  9. The Nearby Supernova FactoryThe Nearby Supernova Factory W.M. Wood-Vasey, G. Aldering, B. C. Lee, S. Loken, P. Nugent, S. Perlmutter, R. Quimby, J. Siegrist, L. Wang Lawrence Berkeley National Lab

    E-Print Network [OSTI]

    .4 0.45 0.5 SupernovaeDiscovered/year/0.02 MagnitudeError Redshift Redshift distribution for Various

  10. Elemental Abundances of Nearby Galaxies through High Signal-to-Noise XMM-Newton Observations of ULXs

    E-Print Network [OSTI]

    Lisa M. Winter; Richard F. Mushotzky; Christopher S. Reynolds

    2006-10-12T23:59:59.000Z

    (abridged) In this paper, we examined XMM Newton EPIC spectra of 14 ultra-luminous X-ray sources (ULXs)in addition to the XMM RGS spectra of two sources (Holmberg II X-1 and Holmberg IX X-1). We determined oxygen and iron abundances of the host galaxy's interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards these ULXs. We found that the oxygen abundances closely matched recent solar abundances for all of our sources, implying that ULXs live in similar local environments despite the wide range of galaxy host properties. Also, we compare the X-ray hydrogen column densities (n_H) for 8 ULX sources with column densities obtained from radio H I observations. The X-ray model n_H values are in good agreement with the H I n_H values, implying that the hydrogen absorption towards the ULXs is not local to the source (with the exception of the source M81 XMM1). In order to obtain the column density and abundance values, we fit the X-ray spectra of the ULXs with a combined power law and one of several accretion disk models. We tested the abundances obtained from the XSPEC models bbody, diskbb, grad, and diskpn along with a power law, finding that the abundances were independent of the thermal model used. We comment on the physical implications of these different model fits. We also note that very deep observations allow a breaking of the degeneracy noted by Stobbart et al. (2006) favoring a high mass solution for the absorbed grad + power law model.

  11. 2MASS J035523.37+113343.7: A YOUNG, DUSTY, NEARBY, ISOLATED BROWN DWARF RESEMBLING A GIANT EXOPLANET

    SciTech Connect (OSTI)

    Faherty, Jacqueline K. [Department of Astronomy, Universidad de Chile Cerro Calan, Las Condes (Chile); Rice, Emily L.; Cruz, Kelle L.; Nunez, Alejandro [Department of Astrophysics , American Museum of Natural History, Central Park West at 79th Street, New York, NY 10034 (United States); Mamajek, Eric E., E-mail: jfaherty17@gmail.com, E-mail: jfaherty@amnh.org [Cerro Tololo Inter-American Observatory, Casilla 603, La Serena (Chile)

    2013-01-01T23:59:59.000Z

    We present parallax and proper motion measurements, near-infrared spectra, and Wide-field Infrared Survey Explorer photometry for the low surface gravity L5{gamma} dwarf 2MASS J035523.37+113343.7 (2M0355). We use these data to evaluate photometric, spectral, and kinematic signatures of youth as 2M0355 is the reddest isolated L dwarf yet classified. We confirm its low-gravity spectral morphology and find a strong resemblance to the sharp triangular shaped H-band spectrum of the {approx}10 Myr planetary-mass object 2M1207b. We find that 2M0355 is underluminous compared to a normal field L5 dwarf in the optical and Mauna Kea Observatory J, H, and K bands and transitions to being overluminous from 3 to 12 {mu}m, indicating that enhanced photospheric dust shifts flux to longer wavelengths for young, low-gravity objects, creating a red spectral energy distribution. Investigating the near-infrared color-magnitude diagram for brown dwarfs confirms that 2M0355 is redder and underluminous compared to the known brown dwarf population, similar to the peculiarities of directly imaged exoplanets 2M1207b and HR8799bcd. We calculate UVW space velocities and find that the motion of 2M0355 is consistent with young disk objects (<2-3 Gyr) and it shows a high likelihood of membership in the AB Doradus association.

  12. Stellar Parameters for HD 69830, a Nearby Star with Three Neptune Mass Planets and an Asteroid Belt

    E-Print Network [OSTI]

    Tanner, Angelle; von Braun, Kaspar; Kane, Stephen; Brewer, John M; Farrington, Chris; van Belle, Gerard T; Beichman, Charles A; Fischer, Debra; Brummelaar, Theo A ten; McAlister, Harold A; Schaefer, Gail

    2014-01-01T23:59:59.000Z

    We used the CHARA Array to directly measure the angular diameter of HD 69830, home to three Neptune mass planets and an asteroid belt. Our measurement of 0.674+/-0.014 milli-arcseconds for the limb-darkened angular diameter of this star leads to a physical radius of R$_*$ = 0.9058$\\pm$0.0190 R\\sun and luminosity of L* = 0.622+/-0.014 Lsun when combined with a fit to the spectral energy distribution of the star. Placing these observed values on an Hertzsprung-Russel (HR) diagram along with stellar evolution isochrones produces an age of 10.6+/-4 Gyr and mass of 0.863$\\pm$0.043 M\\sun. We use archival optical echelle spectra of HD 69830 along with an iterative spectral fitting technique to measure the iron abundance ([Fe/H]=-0.04+/-0.03), effective temperature (5385+/-44 K) and surface gravity (log g = 4.49+/-0.06). We use these new values for the temperature and luminosity to calculate a more precise age of 7.5+/-Gyr. Applying the values of stellar luminosity and radius to recent models on the optimistic locati...

  13. 70 IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS, VOL. 10, NO. 1, MARCH 2009 Critical Motion Detection of Nearby Moving

    E-Print Network [OSTI]

    Rucci, Michele

    ) active. Passive approaches (e.g., seat belts and airbags) are intended to reduce the degree of injury

  14. Nearby Supernova Factory Observations of SN 2005gj: Another Type Ia Supernova in a Massive Circumstellar Envelope

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    scenarios both involve the thermonuclear disruption of whitelead to new channels for thermonuclear SNe. For example,thermonuclear SNe inside a dense

  15. The nearby eclipsing stellar system delta Velorum - I. Origin of the infrared excess from VISIR and NACO imaging

    E-Print Network [OSTI]

    Pierre Kervella; Frédéric Thévenin; Monika Petr-Gotzens

    2008-11-11T23:59:59.000Z

    - Context: The triple stellar system delta Vel system presents a significant infrared excess, whose origin is still being debated. A large infrared bow shock has been discovered using Spitzer/MIPS observations. Although it appears as a significant contributor to the measured IR excess, the possibility exists that a circumstellar IR excess is present around the stars of the system. - Aims: The objective of the present VISIR and NACO observations is to identify whether one of the stars of the delta Vel system presents a circumstellar photometric excess in the thermal IR domain and to quantify it. - Methods: We observed delta Vel using the imaging modes of the ESO/VLT instruments VISIR (in BURST mode) and NACO to resolve the A-B system (0.6" separation) and obtain the photometry of each star. We also obtained one NACO photometry epoch precisely at the primary (annular) eclipse of delta Vel Aa by Ab. - Results: Our photometric measurements with NACO (2.17 mic), complemented by the existing visible photometry allowed us to reconstruct the spectral energy distribution of the three stars. We then compared the VISIR photometry (8.6-12.8 mic) to the expected photospheric emission from the three stars at the corresponding wavelengths. - Conclusions: We can exclude the presence of a circumstellar thermal infrared excess around delta Vel A or B down to a few percent level. This supports the conclusions of Gaspar et al. (2008) that the IR excess of delta Vel has an interstellar origin, although a cold circumstellar disk could still be present. In addition, we derive the spectral types of the three stars Aa, Ab, and B (respectively A2IV, A4V and F8V), and we estimate the age of the system around 400-500 Myr.

  16. A case study of electron precipitation in the late substorm growth phase on and nearby a preonset arc

    E-Print Network [OSTI]

    Boyer, Edmond

    Finnish Meteorological Institute, Helsinki, Finland Received: 15 September 1997 a Accepted: 26 March 1998, and consequently a dayside reconnection resulting in en- hanced convection directly driven by the solar wind), and a loading of energy in the magnetotail will go on until the onset of the substorm, when a second current

  17. Assessing effects of highway bridge deck runoff on near-by recieving waters in coastal margins using remote monitoring techniques

    E-Print Network [OSTI]

    Nwaneshiudu, Oke

    2005-02-17T23:59:59.000Z

    point sources), highway runnoff can be considered a serious problem if not handeled properly (FHWA 1999). If the required best management practices are not taken for excess contaminant removal, highway runnoff can have adverse effects. The most... waters, is rainfall. The main objective of this runoff study was to characterize and assess the quantity and quality of the storm water runoff of a bridge deck that discharged into a receiving water body. The bridge deck and the creek were located...

  18. Spectral Energy Distribution of Radio Sources in Nearby Clusters of Galaxies: Implications for Sunyaev-Zel'dovich Effect Surveys

    E-Print Network [OSTI]

    Yen-Ting Lin; Bruce Partridge; J. C. Pober; Khadija El Bouchefry; Sarah Burke; Jonathan Klein; Joseph Coish; Kevin Huffenberger

    2009-04-04T23:59:59.000Z

    To explore the high frequency radio spectra of galaxies in clusters, we used NRAO's Very Large Array at four frequencies, 4.9-43 GHz, to observe 139 galaxies in low redshift (z22 GHz, implying a higher flux than would be expected from an extrapolation of the lower frequency flux measurements. Our results quantify the need for careful source subtraction in increasingly sensitive measurements of the Sunyaev-Zel'dovich effect in clusters of galaxies (as currently being conducted by, for instance, the Atacama Cosmology Telescope and South Pole Telescope groups).

  19. The ESO Nearby Abell Cluster Survey IX. The morphology-radius and morphology-density relations in rich galaxy clusters

    E-Print Network [OSTI]

    T. Thomas; P. Katgert

    2005-10-10T23:59:59.000Z

    We study the morphology-radius (MR-) and morphology-density (MD-) relations for a sample of about 850 galaxies (with M = -22), the S0 galaxies and the early spirals have different Sigma1-distributions. The reason for this is that Sigma1 is much less correlated with R than is Sigma10, and thus has much less cross-talk from the (MR-) relation. On average, the 'normal' ellipticals populate environments with higher projected density than do the S0 galaxies while the early spirals populate even less dense environments. The segregation of the brightest ellipticals and the late spirals is driven mostly by global factors, while the segregation between 'normal' ellipticals, S0 galaxies and early spirals is driven primarily by local factors.

  20. Near-Infrared Adaptive Optics Imaging of the Central Regions of Nearby Sc Galaxies: I. M33

    E-Print Network [OSTI]

    T. J. Davidge

    1999-10-18T23:59:59.000Z

    Near-infrared images obtained with the Canada-France-Hawaii Telescope (CFHT) Adaptive Optics Bonnette (AOB) are used to investigate the stellar content within 18 arcsec of the center of the Local Group spiral galaxy M33. AGB stars with near-infrared spectral-energy distributions similar to those of giants in the solar neighborhood and Baade's Window are detected over most of the field. The bolometric luminosity function (LF) of these stars has a discontinuity near M_{bol} = -5.25, and comparisons with evolutionary tracks suggest that most of the AGB stars formed in a burst of star formation 1 - 3 Gyr in the past. The images are also used to investigate the integrated near-infrared photometric properties of the nucleus and the central light concentration. The nucleus is bluer than the central light concentration, in agreement with previous studies at visible wavelengths. The CO index of the central light concentration 0.5 arcsec from the galaxy center is 0.05, which corresponds to [Fe/H] = -1.2 for simple stellar systems. Hence, the central light concentration could not have formed from the chemically-enriched material that dominates the present-day inner disk of M33.

  1. A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular Clusters and Nearby Bulge Fields

    E-Print Network [OSTI]

    T. J. Davidge

    2000-08-25T23:59:59.000Z

    Images recorded through J, H, K, 2.2 micron continuum and CO filters have been obtained of a sample of metal-poor ([Fe/H] < -1.3) globular clusters in the inner spheroid of the Galaxy. The shape and color of the upper giant branch on the (K, J-K) CMD, combined with the K brightness of the RGB-tip, are used to estimate the metallicity, reddening, and distance of each cluster. CO indices are used to identify bulge stars, which will bias metallicity and distance estimates if not removed from the data. Bulge fields were also observed near each cluster. The slope of the bulge giant branch luminosity function does not vary between most fields, although the LFs in Baade's Window and near NGC 6273 are significantly shallower than average. The data also suggest that the HB content may not be uniform throughout the bulge, in the sense that a larger than average number of red HB stars may occur in fields closest to the Galactic Center.

  2. Simulation study of dose enhancement in a cell due to nearby carbon and oxygen in particle radiotherapy

    E-Print Network [OSTI]

    Shin, Jae Ik; Cho, Sungho; Kim, Eun Ho; Song, Yongkeun; Jung, Won-Gyun; Yoo, SeungHoon; Shin, Dongho; Lee, Se Byeong; Yoon, Myonggeun; Incerti, Sebastian; Geso, Moshi; Rosenfeld, Anatoly B

    2015-01-01T23:59:59.000Z

    The aim of this study is to investigate the dose-deposition enhancement by alpha-particle irradiation in a cellular model using carbon and oxygen chemical compositions.A simulation study was performed to study dose enhancement due to carbon and oxygen for a human cell where Geant4 code used for the alpha-particle irradiation to the cellular phantom. The characteristic of dose enhancement in the nucleus and cytoplasm by the alpha-particle radiation was investigated based on concentrations of the carbon and oxygen compositions and was compared with those by gold and gadolinium.The results show that both the carbon and oxygen-induced dose enhancement was found to be more effective than those of gold and gadolinium. We found that the dose-enhancement effect was more dominant in the nucleus than in the cytoplasm if carbon or oxygen is uniformly distributed in a whole cell. In the condition that the added chemical composition was inserted only into the cytoplasm, the effect of the dose enhancement in nucleus become...

  3. TECHNICAL EVALUATION OF TEMPORAL GROUNDWATER MONITORING VARIABILITY IN MW66 AND NEARBY WELLS, PADUCAH GASEOUS DIFFUSION PLANT

    SciTech Connect (OSTI)

    Looney, B.; Eddy-Dilek, C.

    2012-08-28T23:59:59.000Z

    Evaluation of disposal records, soil data, and spatial/temporal groundwater data from the Paducah Gaseous Diffusion Plant (PGDP) Solid Waste Management Unit (SWMU) 7 indicate that the peak contaminant concentrations measured in monitoring well (MW) 66 result from the influence of the regional PGDP NW Plume, and does not support the presence of significant vertical transport from local contaminant sources in SWMU 7. This updated evaluation supports the 2006 conceptualization which suggested the high and low concentrations in MW66 represent different flow conditions (i.e., local versus regional influences). Incorporation of the additional lines of evidence from data collected since 2006 provide the basis to link high contaminant concentrations in MW66 (peaks) to the regional 'Northwest Plume' and to the upgradient source, specifically, the C400 Building Area. The conceptual model was further refined to demonstrate that groundwater and the various contaminant plumes respond to complex site conditions in predictable ways. This type of conceptualization bounds the expected system behavior and supports development of environmental cleanup strategies, providing a basis to support decisions even if it is not feasible to completely characterize all of the 'complexities' present in the system. We recommend that the site carefully consider the potential impacts to groundwater and contaminant plume migration as they plan and implement onsite production operations, remediation efforts, and reconfiguration activities. For example, this conceptual model suggests that rerouting drainage water, constructing ponds or basin, reconfiguring cooling water systems, capping sites, decommissioning buildings, fixing (or not fixing) water leaks, and other similar actions will potentially have a 'direct' impact on the groundwater contaminant plumes. Our conclusion that the peak concentrations in MW66 are linked to the regional PGDP NW Plume does not imply that there TCE is not present in SWMU 7. The available soil and groundwater data indicate that the some of the waste disposed in this facility contacted and/or were contaminated by TCE. In our assessment, the relatively small amount of TCE associated with SWMU 7 is not contributing detectable TCE to the groundwater and does not represent a significant threat to the environment, particularly in an area where remediation and/or management of TCE in the NW plume will be required for an extended timeframe. If determined to be necessary by the PGDP team and regulators, additional TCE characterization or cleanup activities could be performed. Consistent with the limited quantity of TCE in SWMU 7, we identify a range of low cost approaches for such activities (e.g., soil gas surveys for characterization or SVE for remediation). We hope that this information is useful to the Paducah team and to their regulators and stakeholders to develop a robust environmental management path to address the groundwater and soil contamination associated with the burial ground areas.

  4. Searching for GRB remnants in nearby galaxies S. G. Bhargavi , J. Rhoads + , R. perna # , J. Feldmeier and J. Greiner

    E-Print Network [OSTI]

    Greiner, Jochen

    : due to the effect of radiation of GRB and its afterglow. The UV afterglow flux of a GRB heats gas, the cooling rate being as slow as #24; 10 5 yrs Slowing remnant : due to the slowing blast­wave. The relativistically expanding blast wave resulting from a GRB explosion takes #24; 10 7 years to slow down and merge

  5. Can we explain AMS-02 antiproton and positron excesses simultaneously by nearby supernovae without pulsars nor dark matter?

    E-Print Network [OSTI]

    Kohri, Kazunori; Fujita, Yutaka; Yamazaki, Ryo

    2015-01-01T23:59:59.000Z

    We explain the excess of the antiproton fraction recently reported by the AMS-02 experiment by considering collisions between cosmic-ray protons accelerated by a local supernova remnant (SNR) and the surrounding dense cloud. The same "pp collisions" provide the right branching ratio to fit the observed positron excess simultaneously without a fine tuning. The supernova happened in relatively lower metalicity than the major cosmic-ray sources. The cutoff energy of electrons marks the supernova age of ~10^{5} years, while the antiproton excess may extend to higher energy. Both antiproton and positron fluxes are completely consistent with our predictions in Fujita, Kohri, Yamazaki and Ioka (2009).

  6. Nearby Supernova Factory Observations of SN 2006D: On Sporadic Carbon Signatures in Early Type Ia Supernova Spectra

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    with low volume-?lling factor. Subject headings: supernovae:general — supernovae: individual (SN 2006D)Introduction Type Ia supernovae (SNe Ia) make valuable

  7. Microsoft Word - DOE-ID-INL-12-021.docx

    Broader source: Energy.gov (indexed) [DOE]

    new 100' tall steel tower and guy wire system. 3. Install (3) new approx 3' to 5' tall PVCconcrete receiver tower configurations near the main tower assembly. 4. Install new...

  8. Core Transcriptional Regulatory Circuit Controlled by the TAL1 Complex in Human T Cell Acute Lymphoblastic Leukemia

    E-Print Network [OSTI]

    Sanda, Takaomi

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in over 40% of cases of human T cell acute lymphoblastic leukemia (T-ALL), emphasizing its importance in the molecular pathogenesis of T-ALL. Here we ...

  9. Assessing a potential correlation between protein stability and function of the HMG domain of Lymphoid Enhancer Binding Factor-1

    E-Print Network [OSTI]

    Ly, Youly

    2012-01-01T23:59:59.000Z

    of LEF1 in T-cell acute lymphoblastic leukemia. Blood 115,pathways in T cell acute lymphoblastic leukemia. Cancer Cellsuch as T-cell acute lymphoblastic leukemia (T-ALL). T-ALL

  10. The MODIS (Collection V005) BRDF/albedo product: Assessment of spatial representativeness over forested landscapes

    E-Print Network [OSTI]

    2009-01-01T23:59:59.000Z

    of a combination of wetlands and/or an aspen grove.Both wetlands and aspen are deciduous covers which, in this7.0 m tall jack pine and aspen, various 1.0–6.0 m tall black

  11. OBPRM: An ObstacleBased PRM for 3D Workspaces Nancy M. Amato, Texas A&M University, College Station, TX, USA

    E-Print Network [OSTI]

    LaValle, Steven M.

    methods, known as Probabilistic Roadmap Methods (prms) have shown great potential for solving compli a graph of representative paths in C­space (a roadmap) whose vertices correspond to collision roadmap method (obprm), in cluttered 3­dimensional Workspaces. Various node generation strategies

  12. The Effectiveness of Emergency Preparedness Animal Issues Education: Perceived Advantages and Obstacles of Roles Played By Texas AgriLife Extension Service Agents

    E-Print Network [OSTI]

    Maxwell, Ricky G.

    2010-07-14T23:59:59.000Z

    million in the Turks and Caicos, amounting to a total of $32 billion in 18 Texas Tech University, Rick Maxwell, May 2010 damages. Ike was the third costliest Atlantic hurricane of all time, behind Hurricane Andrew of 1992 and Hurricane Katrina of 2005... Background The past few years have brought several natural disasters to the United States and especially the southern states. Hurricanes Katrina and Rita brought massive devastation to the gulf coast region, especially in the states of Louisiana...

  13. Obstacles to the application of soil and water conservation practices on tenant-operated farms cooperating with the Navarro-Hill Soil Conservation District

    E-Print Network [OSTI]

    Boykin, Calvin C

    1956-01-01T23:59:59.000Z

    laxxAloxd haa a long time stake in the maintenance of' hia soil resources, chile tha tenant, by vixtuc of tbs limits of hia contract, is primarily concerned with the aurrsat year's xeturns. Thus, a conf'. ct of interacts frecuezA)g retards...

  14. Proceedings of the 1998 IEEE International Conference on Robotics and Automation. Leuven, Belgium, May 1621, 1998, pp. 1572 -1577 VFH+: Reliable Obstacle Avoidance for Fast Mobile Robots

    E-Print Network [OSTI]

    Borenstein, Johann

    to this algorithm is a map grid of the local environment, called histogram grid [Borenstein and Koren, 1991], which. In the first three stages, the two-dimensional map grid is reduced to one-dimensional polar histograms the active region Ca of the map grid C onto the primary polar histogram Hp . The active region Ca

  15. ITER Siting Decision Clears One Important Obstacle in Congress "This is real . . . we've got a project on our hands." -DOE Office of Science

    E-Print Network [OSTI]

    in Moscow that representatives of the United States, European Union, Japan, the Russia Federation, China in late 2003 (see page 14 of www.sc.doe.gov/Sub/Facilities_for_future/facilities_future.htm .) Congress, he said, has "given reality to the project." DOE's site at http://www.science.doe.gov/ provides

  16. Motion Planning in the Presence of Motling Obstacles 765 trajectories but cannot rotate. This problem has many applications to robot, automobile, and

    E-Print Network [OSTI]

    Reif, John H.

    . This problem has many applications to robot, automobile, and aircraft collision avoidance. Our main positive) Automobile Collision Avoidance. B is an automobile with an automatic steering system that must avoid collision with other automobiles with known trajectories on a highway. #12;766 J. REIF AND M. SHARIR (3

  17. Legal obstacles and incentives to the third development of small-scale hydroelectric potential in the six New England states: executive summary

    SciTech Connect (OSTI)

    None,

    1980-05-01T23:59:59.000Z

    This executive summary describes the relationship of Federal law and regulation to state law and regulation of small-scale hydroelectric facilities. It also highlights important features of the constitutional law, statutory law, case law, and regulations of each of the six New England states. The summary may serve as a concise overview of and introduction to the detailed reports prepared by the Energy Law Institute on the legal and regulatory systems of each of the six states. The dual regulatory system is a function of the federalist nature of our government. This dual system is examined from the standpoint of the appropriate legal doctrine, i.e., the law of pre-emption, and the application of this law to the case of hydroelectric development. The regulation of small dams are discussed and flow diagrams of the regulations are presented for each of the six states - Maine, Massachusetts, Vermont, New Hampshire, Vermont, and Connecticut.

  18. May 18, 2010 14:15 WSPC -Proceedings Trim Size: 9in x 6in paper BEHAVIOR-BASED OBSTACLE DETECTION AND

    E-Print Network [OSTI]

    Berns, Karsten

    they are applied very often to enhance human's capacity to act. One of these tasks is the inspection of large endangering human technicians. In this context our climbing robot project focusses on the development DETECTION AND AVOIDANCE SYSTEM FOR THE OMNIDIRECTIONAL WALL-CLIMBING ROBOT CROMSCI M. JUNG, D. SCHMIDT and K

  19. "Safety Concrete" A Material Designed to Fail

    E-Print Network [OSTI]

    platen Bottom steel platen 10 ft tall PVC pipe (3" ID) Outer PVC shield collects fragments Sample #12

  20. Grass and Legumes for Forage, Pastures and Cover Crops Paul Gross-AABI Educator, Lindsey Gardner-Summer Intern

    E-Print Network [OSTI]

    planting preferred. Fescue-tall (endophyte free) Spring-Sept. 15 or Nov. 1- 20. 15 alone CSP Pasture .or

  1. "Menos y menos da más": Using Spanish as the Language of Instruction with English Learners in Algebra 1

    E-Print Network [OSTI]

    Diaz, Marco Antonio

    2013-01-01T23:59:59.000Z

    L.  R.  ( 1984).   Algebra  :  children's  strategies  and  in  Learning  Algebra.   American   Educational  Research  Tall,  D.  (1994).   Algebra,  Symbols  and  Translation  

  2. An experimental study of intraspecific competition within several forage crops (1).

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ., tall fescue Festuca arundinacea Schreb., lucerne Medicago sativa L. and red clover Trifolium pratense L. Departures from this general rule are discussed. Additional key-words : Cocksfoot, tall fescue, lucerne, red crops (lucerne, red clover, cocksfoot, tall fescue). This program was oriented towards two distinct

  3. A comparison of the distribution of the Echinodermata of a coral community with that of a nearby rock outcrop on the Texas continental shelf

    E-Print Network [OSTI]

    DuBois, Random

    1975-01-01T23:59:59.000Z

    TAYLOR, ATLANTIS and the OREGON, most were concerned either with hydrography or deep water research As pointed out by A. H. Clark (1954), the major portion of' knowledge of the echinoderms of the Gulf of Nexico comes from the work done.... The literature of the Class Asteroidea, extends back to the mid-1800's dominated by E Perrier as well as both Louis and Alexander Agassiz Among later contributors were A H. and H L. Clark~ A E v'li, w. p. Slddl'k th~chll t 'd, d W. K Fisher. Of the many...

  4. Development of a Novel Efficient Solid-Oxide Hybrid for Co-generation of Hydrogen and Electricity Using Nearby Resources for Local Application

    SciTech Connect (OSTI)

    Tao, Greg, G.; Virkar, Anil, V.; Bandopadhyay, Sukumar; Thangamani, Nithyanantham; Anderson, Harlan, U.; Brow, Richard, K.

    2009-06-30T23:59:59.000Z

    Developing safe, reliable, cost-effective, and efficient hydrogen-electricity co-generation systems is an important step in the quest for national energy security and minimized reliance on foreign oil. This project aimed to, through materials research, develop a cost-effective advanced technology cogenerating hydrogen and electricity directly from distributed natural gas and/or coal-derived fuels. This advanced technology was built upon a novel hybrid module composed of solid-oxide fuel-assisted electrolysis cells (SOFECs) and solid-oxide fuel cells (SOFCs), both of which were in planar, anode-supported designs. A SOFEC is an electrochemical device, in which an oxidizable fuel and steam are fed to the anode and cathode, respectively. Steam on the cathode is split into oxygen ions that are transported through an oxygen ion-conducting electrolyte (i.e. YSZ) to oxidize the anode fuel. The dissociated hydrogen and residual steam are exhausted from the SOFEC cathode and then separated by condensation of the steam to produce pure hydrogen. The rationale was that in such an approach fuel provides a chemical potential replacing the external power conventionally used to drive electrolysis cells (i.e. solid oxide electrolysis cells). A SOFC is similar to the SOFEC by replacing cathode steam with air for power generation. To fulfill the cogeneration objective, a hybrid module comprising reversible SOFEC stacks and SOFC stacks was designed that planar SOFECs and SOFCs were manifolded in such a way that the anodes of both the SOFCs and the SOFECs were fed the same fuel, (i.e. natural gas or coal-derived fuel). Hydrogen was produced by SOFECs and electricity was generated by SOFCs within the same hybrid system. A stand-alone 5 kW system comprising three SOFEC-SOFC hybrid modules and three dedicated SOFC stacks, balance-of-plant components (including a tailgas-fired steam generator and tailgas-fired process heaters), and electronic controls was designed, though an overall integrated system assembly was not completed because of limited resources. An inexpensive metallic interconnects fabrication process was developed in-house. BOP components were fabricated and evaluated under the forecasted operating conditions. Proof-of-concept demonstration of cogenerating hydrogen and electricity was performed, and demonstrated SOFEC operational stability over 360 hours with no significant degradation. Cost analysis was performed for providing an economic assessment of the cost of hydrogen production using the targeted hybrid technology, and for guiding future research and development.

  5. Discovery of a nearby twin of SN1987A's nebula around the luminous blue variable HD168625: Was Sk--69 202 an LBV?

    E-Print Network [OSTI]

    Nathan Smith

    2006-11-16T23:59:59.000Z

    Spitzer images of the luminous blue variable (LBV) candidate HD168625 reveal the existence of a bipolar nebula several times larger than its previously-known equatorial dust torus. The outer nebula of HD168625 has a full extent of about 80 arcsec or 0.85 pc, and one of the lobes has a well-defined polar ring. The nebula is a near twin of the triple-ring system around SN1987A. Because of these polar rings, and accounting for stellar/progenitor luminosity, HD168625 is an even closer twin of SN1987A than the B supergiant Sher 25 in NGC3603. HD168625's nebula was probably ejected during a giant LBV eruption and not during a red supergiant phase, so its similarity to the nebula around SN1987A may open new possibilities for the creation of SN1987A's rings. Namely, the hypothesis that Sk-69 202 suffered an LBV-like eruption would avert the complete surrender of single star models for its bipolar nebula by offering an alternative to an unlikely binary merger scenario. It also hints that LBVs are the likely progenitors of some type II supernovae, and that HD168625's nebula is a good example of a pre-explosion environment.

  6. arXiv:1202.0446v1[astro-ph.EP]2Feb2012 A planetary system around the nearby M dwarf GJ 667C with at

    E-Print Network [OSTI]

    Kaye, Paul

    . Introduction The Doppler detection of extrasolar planets is achieved by measuring the periodic radial velocity public archive. The new radial velocity (RV) mea- surements were obtained using a new data analysis technique that derives the Doppler measurement and other instrumental effects using a least-squares ap

  7. Ecological and Geochemical Aspects of Terrestrial Hydrothermal Systems

    E-Print Network [OSTI]

    Forrest, Matthew James

    exploitation of nearby geothermal energy resources. Dixieexploitation of nearby geothermal energy resources. In Napachange (USFWS, 2009), geothermal energy development (BLM,

  8. Introduction 5 Mechanism of Irradiation Hardening 5

    E-Print Network [OSTI]

    these obstacles either by the Orowan mechanism , in which the dislocations bow out between the obstacles, thermal activation can help in overcoming the energy barrier caused by the obstacles. This thermal

  9. actin filament labels: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    irrespective of obstacle geometry, and clarify how simulated and electron tomography data have to be analyzed for non-flat obstacle geometries. Julian Weichsel; Ulrich S....

  10. (DOE/EIS-0285/SA-11): Supplement Analysis for the Transmission...

    Broader source: Energy.gov (indexed) [DOE]

    and Record of Decision (ROD). Planning Steps 1. Identify facility and the vegetation management need. The work involved will be to clear tall growing vegetation that is...

  11. (DOE/EIS-0285/SA-10): Supplement Analysis for the Transmission...

    Broader source: Energy.gov (indexed) [DOE]

    and Record of Decision (ROD). Planning Steps 1. Identify facility and the vegetation management need. The work involved will be to clear tall growing vegetation that is...

  12. (DOE/EIS-0285/SA-27): Supplement Analysis for the Transmission...

    Broader source: Energy.gov (indexed) [DOE]

    and Record of Decision (ROD). Planning Steps 1. Identify facility and the vegetation management need. The work involved will be to clear tall growing vegetation that is...

  13. Supplement Analysis for the Transmission System Vegetation Management...

    Broader source: Energy.gov (indexed) [DOE]

    and Record of Decision (ROD). Planning Steps 1. Identify facility and the vegetation management need. The work involved will be to clear tall growing vegetation that is...

  14. acceptable seismic margin: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to direct mortality of adult grasshoppers and dispersal of individuals from the short, cut vegetation (< 10 cm in height) to surrounding tall grassland due to their need for...

  15. CX-005201: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    Exclusion Determination CX-005201: Categorical Exclusion Determination Tall Tower Wind Energy Monitoring and Numerical Model Validation in Southern Nevada CX(s) Applied: A9,...

  16. (DOE/EIS-0285/SA-12): Supplement Analysis for the Transmission...

    Broader source: Energy.gov (indexed) [DOE]

    managers. The subject corridor traverses mountainous terrain mostly owned by large timber companies. During routine patrols, tall, encroaching trees and vegetation issues...

  17. UF in Osnabrck Understanding Engineering in Europe

    E-Print Network [OSTI]

    Jawitz, James W.

    the chance to climb a 100 meter tall wind generator tower! About the Location Osnabrück is located in Lower

  18. analysis north america: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002 Environmental Sciences and Ecology Websites Summary: quality as they vary with climate in grass- land ecosystems throughout central North America including tall-grass...

  19. Recovery Act Project Clears Portsmouth Switchyard, Benefits Community...

    Office of Environmental Management (EM)

    million Recovery Act project completed safely and on schedule, workers demolished 160 towers as tall as 120 feet that were used to operate the X-533 Electrical Switchyard....

  20. Chapter 2 Transmission Facility Siting, Route Segments and Action...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    towers depending on location; 60 to 280 feet tall depending on voltage and location. Right-of-way easements Generally 150 feet wide depending on location. Wires (lines;...

  1. advances cellulosic ethanol: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Energy Websites Summary: the flexibility to run on numerous biomass feedstocks including wood chips, tall grasses, corn stover (residual biofuels from...

  2. announce major progress: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Energy Websites Summary: the flexibility to run on numerous biomass feedstocks including wood chips, tall grasses, corn stover (residual biofuels from...

  3. advancing biofuels technology: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Energy Websites Summary: the flexibility to run on numerous biomass feedstocks including wood chips, tall grasses, corn stover (residual biofuels from...

  4. announces major commitment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Renewable Energy Websites Summary: the flexibility to run on numerous biomass feedstocks including wood chips, tall grasses, corn stover (residual biofuels from...

  5. Nuclear Instruments and Methods in Physics Research A 461 (2001) 269271 CAPRICE98: a balloon-borne magnetic spectrometer

    E-Print Network [OSTI]

    Morselli, Aldo

    2001-01-01T23:59:59.000Z

    and an angular resolution 52 mrad. It consisted of a 1 m tall box filled with the gas radiator: high-purity C4F10

  6. Proceedings of ICRC 2001: 921 c Copernicus Gesellschaft 2001 A new measurement of muon spectra in the atmosphere

    E-Print Network [OSTI]

    Morselli, Aldo

    ., 1999) consisted of a 1m tall gas radiator filled with high purity C4F10 gas, with an average threshold

  7. In: Proceedings of the Participatory Design Conference (PDC 2000), 29.11. 1.12.2000, New York, pp. 143 147 Obstacles to tele-cooperation in engineering networks of

    E-Print Network [OSTI]

    In: Proceedings of the Participatory Design Conference (PDC 2000), 29.11. ­ 1.12.2000, New York, pp

  8. China's Presence in Rwanda and Africa, through the Lens of the Product Life Cycle Theory

    E-Print Network [OSTI]

    Sofiani, Lily

    2013-01-01T23:59:59.000Z

    South Africa where infrastructure and communication are more attractive to investors. Obstacles such as energy

  9. YouProve: Authenticity and Fidelity in Mobile Sensing Peter Gilbert

    E-Print Network [OSTI]

    , Egypt, and Libya is difficult. Due to logistical obstacles, govern- ment bans, and reprisals against

  10. Joint United States-European Union Theoretical and Practical Course on Molecular Approaches for In Situ Biogradation

    SciTech Connect (OSTI)

    Suflita, Joseph M.; Duncan, Kathleen E.

    2010-08-14T23:59:59.000Z

    The Joint United States - European Union Theoretical and Practical Course on Molecular Approaches for in situ Biodegradation was held May 24 through June 7 at The University of Oklahoma. Twenty-four graduate and postgraduate students from both the United States and the European Union attended the course. Nine states and ten European countries were represented. Students were assigned living quarters and laboratory partners to maximize interactions between US and EU participants as well as to mix people with different technical backgrounds together. The students used the latest methods in molecular biology to characterize beneficial microorganisms and genes involved in the biodegradation of pollutants at a nearby landfill as well as an active hydrocarbon-producing site, part of which is undergoing bioremediation. Seminars by distinguished scientists were organized to expose the students to the breadth of the environmental field, including field assay and engineering applications, laboratory scale bioreactors, microbiology, genetics, regulation, pathway analysis, design of recombinant bacteria, and application of the associated techniques to the field. Lectures were given by various OU faculty on the principles behind the techniques to be used in the laboratory. These lectures included troubleshooting hints and encouraged questions and comments from the audience. The laboratory experiments covered chemical, microbiological, and molecular genetic analyses of soils; bioavailability of contaminants; enrichment cultures; gene probing; PCR amplification of known genes and gene families; identification of microbes based traditional and nontraditional approaches, nutritional capabilities, and 16S rRNA sequence; mRNA detection; and enzyme assays. Field trips were made to the USGS landfill field sampling site, and to the Tall Grass Prairie Preserve, a Nature Conservancy site which also featured long-term studies of bioremediation of crude oil and brine spills by one of the Principal Investigators in collaboration with University of Tulsa faculty. The students are expected to bring the methods that they learned back to their laboratories to enrich their own and their colleagues' ability to perform state of the art environmental biotechnology research.

  11. Transcriptional regulatory networks downstream of TAL1/SCL in T-cell acute lymphoblastic leukemia

    E-Print Network [OSTI]

    Liu, Xiaole Shirley

    pathogene- sis of human T-cell acute lymphoblastic leukemia (T-ALL); however, oncogenic transcriptional expression leads to T-cell acute lymphoblastic leukemia (T-ALL). TAL1 is expressed by the leukemic cellsNEOPLASIA Transcriptional regulatory networks downstream of TAL1/SCL in T-cell acute lymphoblastic

  12. The TAL1 complex targets the FBXW7 tumor suppressor by activating miR-223 in human T cell acute lymphoblastic leukemia

    E-Print Network [OSTI]

    Mansour, Marc R.

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in 60% of cases of human T cell acute lymphoblastic leukemia (T-ALL) and initiates T-ALL in mouse models. By performing global microRNA (miRNA) expression ...

  13. Cancer Cell Complementary Genomic Screens Identify SERCA

    E-Print Network [OSTI]

    Perrimon, Norbert

    -cell acute lymphoblastic leukemia (T-ALL) (Lee et al., 2005; Mansour et al., 2006; Weng et al., 2004. T cell acute lymphoblastic leukemia (T-ALL), a high-risk leukemia in need of better treatment approaches bearing a leukemia- associated mutation. Sarco/endoplasmic reticulum calcium ATPase (SERCA) channels

  14. Blood, 15 december 2006, volume 108, number 13, pp 4198-4201 HOX11L2/TLX3 is transcriptionally activated through T-

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    observed in up to 20% of childhood T-cell acute lymphoblastic leukemia (T-ALL). It affects the BCL11B/CTIP2 rearrangements and chromosomal translocations observed in human T-cell acute lymphoblastic leukemia (T-ALL) often

  15. brief communications 652 | VOL.8 NO.8 | AUGUST2011 | nature methods

    E-Print Network [OSTI]

    Cai, Long

    CRESTtowhole-genomeDNAsequencedataobtained from five childhood T-lineage acute lymphoblastic leukemia (T-ALL) samples with matched `normal' (for-lineage acute lymphoblastic leukemias (t-aLLs) and a human melanoma cell line, coLo-829, identified 160 somatic

  16. The use of ?15N to examine past mangrove stand structures 

    E-Print Network [OSTI]

    Gudeman, Stephanie M.

    2009-06-02T23:59:59.000Z

    using ?13C and ?15N analysis (mean tall ?13C = -28 ‰, mean tall ?15N = 0‰; mean dwarf ?13C = -25‰, mean dwarf ?15N = -10‰), which may also prove useful in examining past mangrove stand structures from sediment cores. 15N label was traced in R. mangle...

  17. Edinburgh Research Explorer Can seasonal and interannual variation in landscape CO2 fluxes

    E-Print Network [OSTI]

    Millar, Andrew J.

    Edinburgh Research Explorer Can seasonal and interannual variation in landscape CO2 fluxes be detected by atmospheric observations of CO2 concentrations made at a tall tower? Citation for published in landscape CO2 fluxes be detected by atmospheric observations of CO2 concentrations made at a tall tower

  18. www.ext.vt.edu Produced by Communications and Marketing, College of Agriculture and Life Sciences,

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    , the primary forage base is endophyte- infected (E+) Kentucky 31 (KY31) tall fescue. Tall fescue sets performance and disorders caused by the presence of the fungal endophyte Neotyphodium coenophialum reduces its-infected. The endophytic fungus produces ergot alkaloids that are toxic to livestock (Ball, Hoveland, and Lacefield 2002

  19. Ecology, 88(1), 2007, pp. 1825 2007 by the Ecological Society of America

    E-Print Network [OSTI]

    Rudgers, Jennifer

    arundinaceum (tall fescue), hosts a fungal endophyte that is toxic to herbivores. In replicated experimental grasslands, the presence of the endophyte in tall fescue reduced tree abundance and size, altered tree spp.) was 65% higher in plots with the endophyte at the one grassland site where these data were

  20. www.ext.vt.edu Produced by Communications and Marketing, College of Agriculture and Life Sciences,

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    In 2003, the cumulative weight gain of steers on Ken- tucky 31 endophyte-free tall fescue (KY31 E-) was more than that of steers on Lakota prairie grass, Ken- tucky 31 endophyte-infected tall fescue (KY31 E

  1. WESEP 594 Seminar Sri Sritharan

    E-Print Network [OSTI]

    McCalley, James D.

    Energy initiative (http://www.engineering.iastate.edu/wei) · Design of Tall Towers Must withstand large Research · Anything else? #12;My Research program (2000 to 2009) #12;My Involvement in Wind Energy · Wind lateral and torsional loads · Use high performance concrete · Modularize construction #12;Tall Towers

  2. Comparaison des dynamiques d'apparition et de mortalit des organes de ftuque leve,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and senescence rates in tall fescue, cocksfoot and lucerne (leaves, tillers and stems). Three forage species (tall fescue, cocksfoot, lucerne) were cultivated without nitrogen and water stress. Rates of leaf in summer and1 in autumn for lucerne). We showed that the average phyllochrones were 83 degree

  3. ORIGINAL PAPER Distribution and ecological role of the non-native macroalga

    E-Print Network [OSTI]

    McGlathery, Karen

    and by the presence of the tube-building polychaete Diopatra cuprea on adja- cent mudflats, which have been shown quadrats on the border between the mudflat and tall Spartina alterniflora, 51% within the tall S on the adjacent mudflats. Of the incorporated thalli, 3­9% ended up in the marsh, demonstrating connectivity

  4. VLBA DETERMINATION OF THE DISTANCE TO NEARBY STAR-FORMING REGIONS. IV. A PRELIMINARY DISTANCE TO THE PROTO-HERBIG AeBe STAR EC 95 IN THE SERPENS CORE

    SciTech Connect (OSTI)

    Dzib, Sergio; Loinard, Laurent; Rodriguez, Luis F. [Centro de RadioastronomIa y Astrofisica, Universidad Nacional Autonoma de Mexico Apartado Postal 3-72, 58090, Morelia, Michoacan (Mexico); Mioduszewski, Amy J. [National Radio Astronomy Observatory, Domenici Science Operations Center, 1003 Lopezville Road, Socorro, NM 87801 (United States); Boden, Andrew F. [Division of Physics, Math, and Astronomy, California Institute of Technology, 1200 E California Blvd., Pasadena, CA 91125 (United States); Torres, Rosa M., E-mail: s.dzib@crya.unam.m [Argelander Institute for Astronomy, University of Bonn, Auf dem Huegel 71, 53121 Bonn (Germany)

    2010-08-01T23:59:59.000Z

    Using the Very Long Base Array, we observed the young stellar object EC 95 in the Serpens cloud core at eight epochs from 2007 December to 2009 December. Two sources are detected in our field and are shown to form a tight binary system. The primary (EC 95a) is a 4-5 M {sub sun} proto-Herbig AeBe object (arguably the youngest such object known), whereas the secondary (EC 95b) is most likely a low-mass T Tauri star. Interestingly, both sources are non-thermal emitters. While T Tauri stars are expected to power a corona because they are convective while they go down the Hayashi track, intermediate-mass stars approach the main sequence on radiative tracks. Thus, they are not expected to have strong superficial magnetic fields, and should not be magnetically active. We review several mechanisms that could produce the non-thermal emission of EC 95a and argue that the observed properties of EC 95a might be most readily interpreted if it possessed a corona powered by a rotation-driven convective layer. Using our observations, we show that the trigonometric parallax of EC 95 is {pi} = 2.41 {+-} 0.02 mas, corresponding to a distance of 414.9{sup +4.4} {sub -4.3} pc. We argue that this implies a distance to the Serpens core of 415 {+-} 5 pc and a mean distance to the Serpens cloud of 415 {+-} 25 pc. This value is significantly larger than previous estimates (d {approx} 260 pc) based on measurements of the extinction suffered by stars in the direction of Serpens. A possible explanation for this discrepancy is that these previous observations picked out foreground dust clouds associated with the Aquila Rift system rather than Serpens itself.

  5. Safety Evaluation Report: Development of a Novel Efficient Solid-Oxide Hybrid for Co-generation of Hydrogen and Electricity Using Nearby Resources for Local Applications, Materials and Systems Research, Inc. (MSRI), Salt Lake City, UT, February 17, 2009

    SciTech Connect (OSTI)

    Barilo, Nick F.; Frikken, Don; Skolnik, Edward G.; Weiner, Steven C.

    2009-07-16T23:59:59.000Z

    Following a telephone interview with Materials and Systems Research, Inc. (MSRI) by members of the Hydrogen Safety Panel on December 4, 2008, a safety review team was dispatched to Salt Lake City, UT to perform a site-visit review. The major topic of concern was the presence of a hydrogen storage and dispensing shed on the MSRI premises close to both its own laboratory/office building and to the adjoining property. The metal shed contains 36 cylinders (two 18-cylinder "pods") of hydrogen all connected to a common manifold and used to supply hydrogen to a U.S. Department of Energy (DOE) fuel cell project plus several other projects using an entire pod as a common supply. In busy times, MSRI uses and replaces one pod per week. As a result of the site visit, the safety review team has raised some concern with the shed’s location, design, use, and safety features as well as other components of the facility, including the laboratory area.

  6. A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry

    E-Print Network [OSTI]

    Goodbar, Ariel

    2008-01-01T23:59:59.000Z

    spectroscopically peculiar supernovae, and to search for anyK Correction for Type Ia Supernovae: Comparing R-bandK Correction for Type Ia Supernovae: Comparing R-band

  7. High-dynamic-range extinction mapping of infrared dark clouds: Dependence of density variance with sonic Mach number in molecular clouds

    E-Print Network [OSTI]

    Kainulainen, Jouni

    2012-01-01T23:59:59.000Z

    Measuring the mass distribution of infrared dark clouds (IRDCs) over the wide dynamic range of their column densities is a fundamental obstacle in determining the initial conditions of high-mass star formation and star cluster formation. We present a new technique to derive high-dynamic-range, arcsecond-scale resolution column density data for IRDCs and demonstrate the potential of such data in measuring the density variance - sonic Mach number relation in molecular clouds. We combine near-infrared data from the UKIDSS/Galactic Plane Survey with mid-infrared data from the Spitzer/GLIMPSE survey to derive dust extinction maps for a sample of ten IRDCs. We then examine the linewidths of the IRDCs using 13CO line emission data from the FCRAO/Galactic Ring Survey and derive a column density - sonic Mach number relation for them. For comparison, we also examine the relation in a sample of nearby molecular clouds. The presented column density mapping technique provides a very capable, temperature independent tool f...

  8. Station GPS permanente IPG Paris DGF Uchile UNAP Iquique

    E-Print Network [OSTI]

    Vigny, Christophe

    fence but generally open Security ??? telephone nearby NONO Electric power nearby NONO Solar panels + regulator + solar battery equipment storage available NONO possibility of leaving the equipment without

  9. Synoptic and local influences on boundary layer processes, with an application to California wind power

    E-Print Network [OSTI]

    Mansbach, David K

    2010-01-01T23:59:59.000Z

    power conversion facilities, nearby METARs stations, and other ob- servation and buoypower con- version facilities, nearby METARs stations, and other observation and buoy

  10. On the hyperplanes arrangements in mixed-integer techniques

    E-Print Network [OSTI]

    2010-09-28T23:59:59.000Z

    the obstacles in the best path generation is provided. Other works, like [9], consider ..... a target position while avoiding the randomly distributed obstacles. .... Navigation, and Control Conference, Providence, Rhode Island, USA,. 16-19 August ...

  11. Branch-and-Lift Algorithm for Global Optimal Control

    E-Print Network [OSTI]

    2013-07-23T23:59:59.000Z

    example in controlling a car or a robot in the presence of obstacles, a local solver will typically fail to determine whether passing a given obstacle on the right or ...

  12. Role-Based Multicast in Highly Mobile but Sparsely Connected Ad Hoc Networks

    E-Print Network [OSTI]

    Briesemeister, Linda

    airbag ig- nition. Then, it can report the accident instantly to equipped vehicles nearby. We present

  13. Athens Kusadasi Santorini Zakynthos Sicily Amalfi/Positano Rome Florence/Pisa Monte Carlo Marseille Barcelona

    E-Print Network [OSTI]

    McConnell, Terry

    . Depart Athens for Kusadasi and visit the nearby ruins of Ephesus. Admire the beautiful whitewashed towns

  14. May 9 -22, 2011 Special Price Reduction

    E-Print Network [OSTI]

    McConnell, Terry

    and the nearby ruins of Ephesus before arriving in Turkey's captivating capital, Istanbul, an intriguing city

  15. 2010 INTERNATIONAL CONFERENCE ON INDOOR POSITIONING AND INDOOR NAVIGATION (IPIN), 15-17 SEPTEMBER 2010, ZRICH, SWITZERLAND Self-Localization Application for iPhone

    E-Print Network [OSTI]

    Schindelhauer, Christian

    noises, coughing of nearby passengers or other sounds which are ubiquitously available. Based on the TDOA

  16. ORNL is ready with ORNLReady ORNLReady, a Web-based, data-driven interactive

    E-Print Network [OSTI]

    . It includes detailed maps of all ORNL and nearby facilities, employee populations, locations of hazardous

  17. The MasterCard Foundation ScholarsProgram

    E-Print Network [OSTI]

    Shihadeh, Alan

    : _________________________________________________________ (In English) 3. Current home address: ___________________________ /__________________________/______________________ Building/Floor Street Nearby

  18. Paul Murdin how we discovered the cosMos

    E-Print Network [OSTI]

    McReynolds, Ben

    galaxies and therefore rather faint. The appearance of a bright, nearby supernova like Tycho Brahe's `new

  19. Final Report: Mobile Surveillance and Wireless Communication Systems Field Operational Test Volume 2: FOT Objectives, Organization, System Design, Results, Conclusions and Recommendations

    E-Print Network [OSTI]

    Klein, Lawrence

    1999-01-01T23:59:59.000Z

    obstacle to using solar power to charge the ramp metersystem do utilize solar power to supplement power supplied

  20. Minimal Trap Design Pankaj K. Agarwal, Anne D. Collinsy, and John L. Harerz

    E-Print Network [OSTI]

    Agarwal, Pankaj K.

    ].) Along this track is placed a sequence of obstacles (ramps, wiper blades, traps, etc.) designed to allow

  1. Navigation Functions for Focally Admissible Surfaces Ioannis Filippidis and Kostas J. Kyriakopoulos

    E-Print Network [OSTI]

    Low, Steven H.

    focal surface within the obstacle. Secondly, a critical point which is not near a second- order contac

  2. Speed Map for Autonomous Rovers over Rough Terrain

    E-Print Network [OSTI]

    Loh, Jonathan Edau

    2012-01-01T23:59:59.000Z

    Grid Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . .considered obstacles [27] Grid Map showing Tile Size, Cellspeed map. It also covers grid maps and terrain roughness,

  3. Study on Prompting Mechanism of Energy EFficiency Technology

    Office of Energy Efficiency and Renewable Energy (EERE)

    Information on energy efficient technologies, the obstacles surrounding their implementation, and the methods for prompting use of these technologies.

  4. Computational wind engineering using finite element package ADINA

    E-Print Network [OSTI]

    Bajoria, Ankur

    2008-01-01T23:59:59.000Z

    Design of tall and long span structures is governed by the wind forces. Inadequate research in the field of wind dynamics has forced engineers to rely on design codes or wind tunnel tests for sufficient data. The present ...

  5. Rich Hawryluk recalls "exciting and challenging" years working...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    awarded to assemble the six-story-tall fusion facility, or tokamak, that will be at the heart of the complex. Hawryluk is no stranger to exhaustive oversight duties. He served as...

  6. Dynamic range implications for the effectiveness of semi-active tuned mass dampers

    E-Print Network [OSTI]

    Lindh, Cory W

    2010-01-01T23:59:59.000Z

    The response of tall buildings subjected to dynamic wind loads has been widely studied. For excitations approaching the resonant frequencies of the structure, ensuring serviceability is a significant concern. One traditional ...

  7. STRUCTURAL ENGINEERING, MECHANICS AND MATERIALS

    E-Print Network [OSTI]

    Wang, Yuhang

    of companies worldwide; cladding effects on, and hybrid control of, the response of tall buildings Buildings · Masonry Structures · Nano/Microstructure of Cement-based Materials · Polymeric Composite Systems · Reliable Engineering Computing · Risk Analysis · Seismic Hazard Mitigation · Smart Materials

  8. 2014 GRADUATE STUDIES STRUCTURAL ENGINEERING,

    E-Print Network [OSTI]

    Wang, Yuhang

    , the response of tall buildings to earthquake and wind; steel connection design and behavior; and structural engineering and mechanics · Advanced Applied Mathematics in Engineering · Advanced Dynamics and Smart Environments · High-performance Concrete and Steel · Horizontally Curved Bridges · Industrial Buildings

  9. ZFX Controls Propagation and Prevents Differentiation of Acute T-Lymphoblastic and Myeloid Leukemia

    E-Print Network [OSTI]

    Weisberg, Stuart P.

    Tumor-propagating cells in acute leukemia maintain a stem/progenitor-like immature phenotype and proliferative capacity. Acute myeloid leukemia (AML) and acute T-lymphoblastic leukemia (T-ALL) originate from different ...

  10. Lei Zuo, Ph.D., Assistant Professor Department of Mechanical Engineering, State Univ. of New York at Stony Brook, NY 11794-2300

    E-Print Network [OSTI]

    Zuo, Lei

    Energy Research and Development Authority, PI Lei Zuo, 2011-2012 "Vibration Control of Tall Buildings I: Feasibility Study", $8,332, An industry company and NYS SPIR, PI Lei Zuo, 2010-2011 Honors

  11. A study of the molecular mechanics of wood cell walls

    E-Print Network [OSTI]

    Adler, David, S.M. (David C.). Massachusetts Institute of Technology

    2013-01-01T23:59:59.000Z

    Wood is the original structural material, developed by nature to support tall plants. Every advantageous feature of wood as used in artificial structures is rooted in the plant's evolved capability to withstand the conditions ...

  12. Site selection of Henslow's sparrows wintering on the upper Texas Coast

    E-Print Network [OSTI]

    Hannah, Flo

    2000-01-01T23:59:59.000Z

    The Henslow's sparrow (Ammodramus henslowii) selects wintering sites that consist of damp areas with tall grasses, standing dead weeds and scattered shrubs. The smallest study site, a grassy opening at W.G. Jones State Forest, was approximately .76...

  13. Rapid Spatial Distribution Seismic Loss Analysis for Multistory Buildings

    E-Print Network [OSTI]

    Deshmukh, Pankaj Bhagvatrao

    2012-07-16T23:59:59.000Z

    Tall building frames that respond to large seismic ground motions tend to have significant spatial variability of damage over their height, often with a concentration of that damage in the lower stories. In spite of this spatial variability...

  14. Energy Blog | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    in the Pacific Northwest and the Skycrane helicopter that's helping assemble 300-foot tall towers for the transmission lines. previous 253 254 255 256 257 258 259 260 261...

  15. Microsoft Word - Omak-Area-3G-CX.doc

    Broader source: Energy.gov (indexed) [DOE]

    visual value. The new tower at Foster Creek RS is 60' tall and surrounded by similar transmission infrastructure and larger towers, and the EG building at Fox Mt is one of...

  16. Abstract--Transdermal drug delivery through microneedles is a minimally invasive procedure causing little or no pain, and

    E-Print Network [OSTI]

    , several successful fabrication techniques have been reported. Laser micromachining has been employed to create 400-800 µm tall hollow microneedles by drilling trenches in dissolvable molds to create lumens

  17. Heterosis and Composition of Sweet Sorghum 

    E-Print Network [OSTI]

    Corn, Rebecca J.

    2011-02-22T23:59:59.000Z

    Sweet sorghum (Sorghum bicolor) has potential as a bioenergy feedstock due to its high yield potential and the production of simple sugars for fermentation. Sweet sorghum cultivars are typically tall, high biomass types with juicy stalks and high...

  18. CX-005020: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    Categorical Exclusion Determination Provision of Funds to the Idaho Department of Fish and Game For Purchase of the Tall Pines Property CX(s) Applied: B1.25 Date: 01052011...

  19. A computational approach to the design of free form diagrid structure

    E-Print Network [OSTI]

    Sundberg, Jessica Nicole

    2009-01-01T23:59:59.000Z

    In order to satisfy the ever-increasing complexity of modem architectural design of tall towers, diagrid structural systems are becoming more relevant. To deal with irregular geometries, more sophisticated computational ...

  20. Improving parameterization of scalar transport through vegetation in a coupled ecosystem-atmosphere model

    E-Print Network [OSTI]

    Link, Percy Anne

    2008-01-01T23:59:59.000Z

    Several regional-scale ecosystem models currently parameterize subcanopy scalar transport using a rough-wall boundary eddy diffusivity formulation. This formulation predicts unreasonably high soil evaporation beneath tall, ...

  1. Universitat de les Illes Balears CATLEGDEPROJECTESD'INVESTIGACI

    E-Print Network [OSTI]

    Oro, Daniel

    southern Europe and North Africa will combine to work on species including lucerne, cocksfoot, tall fescue) assess the use of molecular genetics in breeding of drought resistant lucerne, (iii) evaluate elite

  2. Propagating Waves Recorded in the Steel, Moment-Frame Factor Building During Earthquakes

    E-Print Network [OSTI]

    Kohler, Monica; Heaton, Thomas H.; Samuel C. Bradford

    2007-01-01T23:59:59.000Z

    studies of damage to tall steel moment-frame buildings inan instrumented 15-story steel- frame building, EarthquakePropagating Waves in the Steel, Moment-Frame Factor Building

  3. ED2 to Saguaro No. 2

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    wood H-frame structures (3.1 miles ) and wood single-pole structures (32.5 miles) with steel monopoles (35.6 miles). The existing structures are 60 to 70 feet tall and the...

  4. Energy Efficiency Evaluation of Guangzhou West Tower Façade System 

    E-Print Network [OSTI]

    Meng, Q.; Zhang, L.

    2006-01-01T23:59:59.000Z

    Guangzhou West Tower is an extremely tall public building. The energy efficiency evaluation of its façade should be different than that of ordinary public buildings. Based on the national code GB50189-2005, “Design Standard for Energy efficiency...

  5. Fuzzy Logic in Computer Science Radim Belohlavek, Rudolf Kruse, and Christian Moewes

    E-Print Network [OSTI]

    Belohlavek, Radim

    truth value from false to true and vice versa. Needless to say, this contradicts our intuition women," or "the class of tall men" do not constitute classes or sets in the usual mathematical sense

  6. Recovery Act Changes Hanford Skyline with Explosive Demolitions

    Office of Environmental Management (EM)

    exhaust chimneys, two 90-foot-fall air filter structures, and a 140-foot-tall water tower. The water tower was marked by a "Work Safely" motto that greeted workers. "Given the...

  7. The nanofluidics can explain ascent of water in tallest trees

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The nanofluidics can explain ascent of water in tallest trees Henri Gouin Abstract. In Amazing, inhomogeneous liquid nanolayers wet the xylem walls of microtubes. The nanofluidic model of crude sap in tall

  8. Technology and society : some insights on the development of metallurgy in the Southern Levant in the light of new dates of slag deposits

    E-Print Network [OSTI]

    Ben-Yosef, Erez

    2008-01-01T23:59:59.000Z

    Survey and Excavation at Wadi Al- Yutum and Tall Al-Magassthe Ancient Copper Mines of the Wadi Amram (South Arabah).Shiqmim Yotvata Nabataean Wadi Fidan 4 Wadi Fidan 4 Khirbat

  9. amerindian pottery figurines: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Topic Index 161 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  10. alcohol tobacco cannabis: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    unknown authors 20 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  11. abandoned urban brownfield: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2007-01-01 266 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  12. anthracis bacteriophage-mediated ecological: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bledsoe, Brian 388 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  13. ambulatory urban patient: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2007-01-01 215 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  14. adult anopheline ecology: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bledsoe, Brian 428 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  15. acque reflue urbane: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2007-01-01 167 THE URBAN ECOLOGY OF CANNABIS CiteSeer Summary: Cannabis sativa aka, hemp, marijuana, or Indian hemp, et al, is a tall, robust, dioecious annual that grows from...

  16. Supplement Analysis for the Transmission System Vegetation Management...

    Broader source: Energy.gov (indexed) [DOE]

    needed as follow-up to treat misses and any other re-growth from 2-3 years after initial treatment. Noxious weed treatments may be needed at this time. Future cycles - As tall...

  17. 2014 Winter UTM Campus Rec Intramural Men's D2 Basketball Schedule

    E-Print Network [OSTI]

    Boonstra, Rudy

    . Noah T'alls 2.0 c. Rick Hansen Storm d. TELP e. Shift Team DIVISION 2 CENTRAL A. Balkan Beasts B. Uncle vs. Bye (NO GAME) (a) 10am: Noah T'alls 2nd vs. Team We 15th (b) 11am: Balkan Beasts 3rd vs. Team'alls 2.0 vs. Green Team (Game B) 12pm: Balkan Beasts vs. Uncle Drew (Game C) 1pm: Telp vs. Shot Callers

  18. Absentee Landowners Near a Military Installation in Texas: Use, Motivation, and Emotional Tie to their Land

    E-Print Network [OSTI]

    Dankert, Amber 1980-

    2012-12-20T23:59:59.000Z

    and fishing activities. Incompatible development includes, but is not limited to, commercial or housing developments, mining and quarry activities, dump sites, erection of tall structures (e.g., power lines, radio towers, or wind turbines), and public..., commercial or housing developments, mining and quarry activities, dump sites, erection of tall structures (e.g., power lines, radio towers, or wind turbines), and public or commercial recreational facilities (e.g., golf courses or ball fields). Ranchette...

  19. 2014-10-08, 7:44 PM--FORESTS: Sugar maples reveal obstacles facing species in their e...nge --researchers --Monday, September 29, 2014 --www.eenews.net Page 1 of 3http://www.eenews.net/climatewire/stories/1060006547/print

    E-Print Network [OSTI]

    Vellend, Mark

    the Appalachian Mountains where temperatures were lower. Sap from these trees is boiled down to produce maple syrup. "We knew the system had warmed, but we weren't seeing the response you would expect," said.3 miles) per decade. Projected temperature increases between 2050 and 2090 under high carbon emissions

  20. Origins of the deflagration-to-detonation transition in gas-phase combustion

    SciTech Connect (OSTI)

    Oran, Elaine S.; Gamezo, Vadim N. [Laboratory for Computational Physics & amp; Fluids Dynamics, US Naval Research Laboratory, Washington, DC 20375 (United States)

    2007-01-15T23:59:59.000Z

    This paper summarizes a 10-year theoretical and numerical effort to understand the deflagration-to-detonation transition (DDT). To simulate DDT from first principles, it is necessary to resolve the relevant scales ranging from the size of the system to the flame thickness, a range that can cover up to 12 orders of magnitude in real systems. This computational challenge resulted in the development of numerical algorithms for solving coupled partial and ordinary differential equations and a new method for adaptive mesh refinement to deal with multiscale phenomena. Insight into how, when, and where DDT occurs was obtained by analyzing a series of multidimensional numerical simulations of laboratory experiments designed to create a turbulent flame through a series of shock-flame interactions. The simulations showed that these interactions are important for creating the conditions in which DDT can occur. Flames enhance the strength of shocks passing through a turbulent flame brush and generate new shocks. In turn, shock interactions with flames create and drive the turbulence in flames. The turbulent flame itself does not undergo a transition, but it creates conditions in nearby unreacted material that lead to ignition centers, or 'hot spots,' which can then produce a detonation through the Zeldovich gradient mechanism involving gradients of reactivity. Obstacles and boundary layers, through their interactions with shocks and flames, help to create environments in which hot spots can develop. Other scenarios producing reactivity gradients that can lead to detonations include flame-flame interactions, turbulent mixing of hot products with reactant gases, and direct shock ignition. Major unresolved questions concern the properties of nonequilibrium, shock-driven turbulence, stochastic properties of ignition events, and the possibility of unconfined DDT. (author)