Ocean General Circulation Models
Yoon, Jin-Ho; Ma, Po-Lun
2012-09-30T23:59:59.000Z
1. Definition of Subject The purpose of this text is to provide an introduction to aspects of oceanic general circulation models (OGCMs), an important component of Climate System or Earth System Model (ESM). The role of the ocean in ESMs is described in Chapter XX (EDITOR: PLEASE FIND THE COUPLED CLIMATE or EARTH SYSTEM MODELING CHAPTERS). The emerging need for understanding the Earth’s climate system and especially projecting its future evolution has encouraged scientists to explore the dynamical, physical, and biogeochemical processes in the ocean. Understanding the role of these processes in the climate system is an interesting and challenging scientific subject. For example, a research question how much extra heat or CO2 generated by anthropogenic activities can be stored in the deep ocean is not only scientifically interesting but also important in projecting future climate of the earth. Thus, OGCMs have been developed and applied to investigate the various oceanic processes and their role in the climate system.
Application of Improved Radiation Modeling to General Circulation Models
Michael J Iacono
2011-04-07T23:59:59.000Z
This research has accomplished its primary objectives of developing accurate and efficient radiation codes, validating them with measurements and higher resolution models, and providing these advancements to the global modeling community to enhance the treatment of cloud and radiative processes in weather and climate prediction models. A critical component of this research has been the development of the longwave and shortwave broadband radiative transfer code for general circulation model (GCM) applications, RRTMG, which is based on the single-column reference code, RRTM, also developed at AER. RRTMG is a rigorously tested radiation model that retains a considerable level of accuracy relative to higher resolution models and measurements despite the performance enhancements that have made it possible to apply this radiation code successfully to global dynamical models. This model includes the radiative effects of all significant atmospheric gases, and it treats the absorption and scattering from liquid and ice clouds and aerosols. RRTMG also includes a statistical technique for representing small-scale cloud variability, such as cloud fraction and the vertical overlap of clouds, which has been shown to improve cloud radiative forcing in global models. This development approach has provided a direct link from observations to the enhanced radiative transfer provided by RRTMG for application to GCMs. Recent comparison of existing climate model radiation codes with high resolution models has documented the improved radiative forcing capability provided by RRTMG, especially at the surface, relative to other GCM radiation models. Due to its high accuracy, its connection to observations, and its computational efficiency, RRTMG has been implemented operationally in many national and international dynamical models to provide validated radiative transfer for improving weather forecasts and enhancing the prediction of global climate change.
Modeling of Antarctic sea ice in a general circulation model
Wu, Xingren; Budd, W.F. [Antarctic Cooperative Research Centre, Tasmania (Australia)] [Antarctic Cooperative Research Centre, Tasmania (Australia); Simmonds, I. [School of Earth Sciences, Victoria (Australia)] [School of Earth Sciences, Victoria (Australia)
1997-04-01T23:59:59.000Z
A dynamic-thermodynamic sea ice model is developed and coupled with the Melbourne University general circulation model to simulate the seasonal cycle of the Antarctic sea ice distributions The model is efficient, rapid to compute, and useful for a range of climate studies. The thermodynamic part of the sea ice model is similar to that developed by Parkinson and Washington, the dynamics contain a simplified ice rheology that resists compression. The thermodynamics is based on energy conservation at the top surface of the ice/snow, the ice/water interface, and the open water area to determine the ice formation, accretion, and ablation. A lead parameterization is introduced with an effective partitioning scheme for freezing between and under the ice floes. The dynamic calculation determines the motion of ice, which is forced with the atmospheric wind, taking account of ice resistance and rafting. The simulated sea ice distribution compares reasonably well with observations. The seasonal cycle of ice extent is well simulated in phase as well as in magnitude. Simulated sea ice thickness and concentration are also in good agreement with observations over most regions and serve to indicate the importance of advection and ocean drift in the determination of the sea ice distribution. 64 refs., 15 figs., 2 tabs.
''Nuclear Winter'': A diagnosis of atmospheric general circulation model simulations
Covey, C.; Thompson, S.L.; Schneider, S.H.
1985-06-20T23:59:59.000Z
We investigate the adiabatic and diabatic thermal balance of an atmospheric general circulation model (GCM) under two conditions: the control case, representing today's atmosphere, and a ''nuclear winter'' scenario in which virtually all sunlight in northern hemisphere and mid-latitudes is absorbed in the upper troposphere by prescribed dense smoke clouds hypothesized to result from the burning of many cities in a nuclear war. We also examine the changes in moisture and cloudiness simulated by the model. Our object is to examine the reliability of existing simulations of the climatic response to assumed dense, widespread, high-altitude smoke and to identify improvements needed in model parameterizations. We find that in the smoke-perturbed case our model simulation of land surface temperature is particularly influenced (i.e., warmed) by parameterized diffusion of heat downward from the lower troposphere. In turn the lower troposphere over land is supplied with heat transported from the relatively warm oceans. Thermal balance in the perturbed atmosphere as a whole is dominated by intense solar heating of the upper troposphere smoke layer in mid-latitudes balanced by parameterized dry convection and large-scale dynamical heat transport. Clouds largely disappear in the mid to upper troposphere in smoke-affected regions as a consequence of a decrease in local relative humidity that results from temperature increases and, to a smaller extent, from a reduction of vertical moisture transport. The computation of substantial downward vertical heat diffusion into the lowest model layer is almost certainly an overestimate for the smoke-perturbed conditions of high vertical stability.
Annular mode-like responses to external forcings in a simple atmospheric general circulation model
Ring, Michael J., 1979-
2008-01-01T23:59:59.000Z
In this thesis, I investigate the response of a simple atmospheric general circulation model to applied forcings to learn whether the annular mode patterns are a preferred model response to the forcings. The thesis is ...
Russell, Lynn
Geophysical Fluid Dynamics Laboratory general circulation model investigation of the indirect Corporation for Atmospheric Research, Geophysical Fluid Dynamics Laboratory, Princeton, New Jersey, USA V. Ramaswamy, Paul A. Ginoux, and Larry W. Horowitz Geophysical Fluid Dynamics Laboratory, Princeton, New
Estimation of OTEC Global Resources with an Ocean General Circulation Model
Frandsen, Jannette B.
Ocean Thermal Energy Conversion (OTEC) relies on the availability of temperature differencesEstimation of OTEC Global Resources with an Ocean General Circulation Model Krishnakumar Rajagopalan Postdoctoral Fellow Department of Ocean and Resources Engineering University of Hawai'i Abstract
GENERAL CIRCULATION Energy Cycle
Grotjahn, Richard
process. PE is useful for global energy balance. Solar radiant energy does not reach the Earth equally everywhere. On average, the tropics receive and absorb far more solar energy annually than the polar regionsGENERAL CIRCULATION Contents Energy Cycle Mean Characteristics Momentum Budget Overview Energy
Fridlind, Ann
jcl92c.tex The Importance of Mesoscale Circulations Generated by SubgridScale Landscape Oceanography, Cook Campus, Rutgers University, New Brunswick, NJ 08903, USA. #12; Abstract A mesoscale. These results emphasize the need to parameterize mesoscale processes induced by landscape discontinuities
Idealized test cases for the dynamical cores of Atmospheric General Circulation Models
Jablonowski, Christiane
Idealized test cases for the dynamical cores of Atmospheric General Circulation Models: A proposal) Ram Nair (NCAR) Mark Taylor (Sandia National Laboratory) May/29/2008 1 Idealized test cases for 3D dynamical cores This document describes the idealized dynamical core test cases that are proposed
Impact Assessment of Satellite-Derived Leaf Area Index Datasets Using a General Circulation Model
Xue, Yongkang
source (i.e., Advanced Very High Resolution Radiometer measurements) on a general circulation model: 10.1175/JCLI4054.1 Â© 2007 American Meteorological Society #12;Very High Resolution Radiometer (AVHRR radiative energy into latent and sensible heat fluxes, which results in discernable warming and decrease
Burtis, M.D. [comp.] [Oak Ridge National Lab., TN (United States). Carbon Dioxide Information Analysis Center; Razuvaev, V.N.; Sivachok, S.G. [All-Russian Research Inst. of Hydrometeorological Information--World Data Center, Obninsk (Russian Federation)
1996-10-01T23:59:59.000Z
This report presents English-translated abstracts of important Russian-language literature concerning general circulation models as they relate to climate change. Into addition to the bibliographic citations and abstracts translated into English, this report presents the original citations and abstracts in Russian. Author and title indexes are included to assist the reader in locating abstracts of particular interest.
Kim, Joong Tae
2007-09-17T23:59:59.000Z
Open water in sea ice, such as leads and polynyas, plays a crucial role in determining the formation of deep- and bottom-water, as well as their long-term global properties and circulation. Ocean general circulation models (GCMs) designed...
Cintra, Rosangela S
2014-01-01T23:59:59.000Z
This paper presents an approach for employing artificial neural networks (NN) to emulate an ensemble Kalman filter (EnKF) as a method of data assimilation. The assimilation methods are tested in the Simplified Parameterizations PrimitivE-Equation Dynamics (SPEEDY) model, an atmospheric general circulation model (AGCM), using synthetic observational data simulating localization of balloon soundings. For the data assimilation scheme, the supervised NN, the multilayer perceptrons (MLP-NN), is applied. The MLP-NN are able to emulate the analysis from the local ensemble transform Kalman filter (LETKF). After the training process, the method using the MLP-NN is seen as a function of data assimilation. The NN were trained with data from first three months of 1982, 1983, and 1984. A hind-casting experiment for the 1985 data assimilation cycle using MLP-NN were performed with synthetic observations for January 1985. The numerical results demonstrate the effectiveness of the NN technique for atmospheric data assimilati...
Gnanadesikan, Anand
shortwave penetration in the high-latitude Southern Ocean causes an increase in the formation of mode waterOcean Water Clarity and the Ocean General Circulation in a Coupled Climate Model ANAND GNANADESIKAN Jersey (Manuscript received 11 October 2007, in final form 17 July 2008) ABSTRACT Ocean water clarity
Covey, C.; Ghan, S.J.; Walton, J.J.; Weissman, P.R.
1989-06-01T23:59:59.000Z
Interception of sunlight by the high altitude worldwide dust cloud generated by impact of a large asteroid or comet would lead to substantial land surface cooling, according to our three-dimensional atmospheric general circulation model (GCM). This result is qualitatively similar to conclusions drawn from an earlier study that employed a one-dimensional atmospheric model, but in the GCM simulation the heat capacity of the oceans substantially mitigates land surface cooling, an effect that one-dimensional models cannot quantify. On the other hand, the low heat capacity of the GCM's land surface allows temperatures to drop more rapidly in the initial stage of cooling than in the one-dimensional model study. These two differences between three-dimensional and one-dimensional model simulations were noted previously in studies of ''nuclear winter; '' GCM-simulated climatic changes in the Alvarez-inspired scenario of ''asteroid/comet winter,'' however, are more severe than in ''nuclear winter'' because the assumed aerosol amount is large enough to intercept all sunlight falling on earth. Impacts of smaller objects -- which would occur much more frequently than the Cretaceous/Tertiary event deduced by Alvarez and coworkers -- could also lead to dramatic, though less severe, climatic changes, according to our GCM. Our conclusion is that it is difficult to imagine an asteroid or comet impact leading to anything approaching complete global freezing, but quite reasonable to assume that impacts at the Alvarez level, or even smaller, dramatically alter the climate in at least a ''patchy'' sense. 30 refs., 4 figs., 1 tab.
Quaas, Johannes; Ming, Yi; Menon, Surabi; Takemura, Toshihiko; Wang, Minghuai; Penner, Joyce E.; Gettelman, Andrew; Lohmann, Ulrike; Bellouin, Nicolas; Boucher, Olivier; Sayer, Andrew M.; Thomas, Gareth E.; McComiskey, Allison; Feingold, Graham; Hoose, Corinna; Kristjansson, Jon Egill; Liu, Xiaohong; Balkanski, Yves; Donner, Leo J.; Ginoux, Paul A.; Stier, Philip; Feichter, Johann; Sednev, Igor; Bauer, Susanne E.; Koch, Dorothy; Grainger, Roy G.; Kirkevag, Alf; Iversen, Trond; Seland, Oyvind; Easter, Richard; Ghan, Steven J.; Rasch, Philip J.; Morrison, Hugh; Lamarque, Jean-Francois; Iacono, Michael J.; Kinne, Stefan; Schulz, Michael
2009-04-10T23:59:59.000Z
Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterizes aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth (Ta) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (Nd) compares relatively well to the satellite data at least over the ocean. The relationship between Ta and liquid water path is simulated much too strongly by the models. It is shown that this is partly related to the representation of the second aerosol indirect effect in terms of autoconversion. A positive relationship between total cloud fraction (fcld) and Ta as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong fcld - Ta relationship, our results indicate that none can be identified as unique explanation. Relationships similar to the ones found in satellite data between Ta and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - Ta relationship show a strong positive correlation between Ta and fcld The short-wave total aerosol radiative forcing as simulated by the GCMs is strongly influenced by the simulated anthropogenic fraction of Ta, and parameterisation assumptions such as a lower bound on Nd. Nevertheless, the strengths of the statistical relationships are good predictors for the aerosol forcings in the models. An estimate of the total short-wave aerosol forcing inferred from the combination of these predictors for the modelled forcings with the satellite-derived statistical relationships yields a global annual mean value of -1.5+-0.5 Wm-2. An alternative estimate obtained by scaling the simulated clear- and cloudy-sky forcings with estimates of anthropogenic Ta and satellite-retrieved Nd - Ta regression slopes, respectively, yields a global annual mean clear-sky (aerosol direct effect) estimate of -0.4+-0.2 Wm-2 and a cloudy-sky (aerosol indirect effect) estimate of -0.7+-0.5 Wm-2, with a total estimate of -1.2+-0.4 Wm-2.
Thompson, S.L.; Ramaswamy, V.; Covey, C.
1987-09-20T23:59:59.000Z
A global atmospheric general circulation model (GCM) is modified to include radiative transfer parameterizations for the absorption and scattering of solar radiation and the absorption of thermal infrared (IR) radiation by smoke aerosols. The solar scattering modifications include a parameterization for diagnosing smoke optical properties as a function of the time- and space-dependent smoke particle radii. The aerosol IR modifications allow for both the ''grey'' absorber approximation and a broadband approximation that resolves the aerosol absorption in four spectral intervals. We examine the sensitivity of some GCM-simulated atmospheric and climatic effects to the optical properties and radiative transfer parameterizations used in studies of massive injections of smoke. Specifically, we test the model response to solar scattering versus nonscattering smoke, variations in prescribed smoke single scattering albedo and IR specific absorption, and interactive versus fixed smoke optical properties. Hypothetical nuclear war created smoke scenarios assume the July injection of 60 or 180 Tg of smoke over portions of the mid-latitude land areas of the northern hemisphere. Atmospheric transport and scavenging of the smoke are included. Nonscattering smoke cases produce roughly 40 Wm/sup -2/ more Earth-atmosphere solar irradiance absorption over the northern hemisphere, when compared to scattering smoke cases having equivalent specific absorption efficiencies. Varying the elemental carbon content of smoke over a plausible range produces a 4/sup 0/--6 /sup 0/C change in average mid-latitude land surface temperature, and a variation of about 0.1 in zonally averaged planetary albedo in the northern hemisphere.
Thornton, P. E.; Doney, S. C.; Lindsay, Keith; Moore, J. K.; Mahowald, N. M.; Randerson, J. T.; Fung, I.; Lamarque, J. F.; Feddema, Johannes J.
2009-01-01T23:59:59.000Z
Biogeosciences, 6, 2099–2120, 2009 www.biogeosciences.net/6/2099/2009/ © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Biogeosciences Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks.... Inclusion of fundamental ecological interactions between carbon and nitrogen cycles in the land component of an atmosphere-ocean general circulation model (AOGCM) leads to decreased carbon uptake associated with CO2 fertil- ization, and increased carbon...
A GENERAL CIRCULATION MODEL FOR GASEOUS EXOPLANETS WITH DOUBLE-GRAY RADIATIVE TRANSFER
Rauscher, Emily [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721-0092 (United States); Menou, Kristen [Department of Astronomy, Columbia University, 550 West 120th Street, New York, NY 10027 (United States)
2012-05-10T23:59:59.000Z
We present a new version of our code for modeling the atmospheric circulation on gaseous exoplanets, now employing a 'double-gray' radiative transfer scheme, which self-consistently solves for fluxes and heating throughout the atmosphere, including the emerging (observable) infrared flux. We separate the radiation into infrared and optical components, each with its own absorption coefficient, and solve standard two-stream radiative transfer equations. We use a constant optical absorption coefficient, while the infrared coefficient can scale as a power law with pressure; however, for simplicity, the results shown in this paper use a constant infrared coefficient. Here we describe our new code in detail and demonstrate its utility by presenting a generic hot Jupiter model. We discuss issues related to modeling the deepest pressures of the atmosphere and describe our use of the diffusion approximation for radiative fluxes at high optical depths. In addition, we present new models using a simple form for magnetic drag on the atmosphere. We calculate emitted thermal phase curves and find that our drag-free model has the brightest region of the atmosphere offset by {approx}12 Degree-Sign from the substellar point and a minimum flux that is 17% of the maximum, while the model with the strongest magnetic drag has an offset of only {approx}2 Degree-Sign and a ratio of 13%. Finally, we calculate rates of numerical loss of kinetic energy at {approx}15% for every model except for our strong-drag model, where there is no measurable loss; we speculate that this is due to the much decreased wind speeds in that model.
Upward Shift of the Atmospheric General Circulation under Global Warming: Theory and Simulations
Singh, Martin Simran
Many features of the general circulation of the atmosphere shift upward in response to warming in simulations of climate change with both general circulation models (GCMs) and cloud-system-resolving models. The importance ...
Arumugam, Sankar
Improving Groundwater Predictions Utilizing Seasonal Precipitation Forecasts from General. The research reported in this paper evaluates the potential in developing 6-month-ahead groundwater Surface Temperature forecasts. Ten groundwater wells and nine streamgauges from the USGS Groundwater
Petascale Atmospheric General Circulation Models R. D. Nair and H. M. Tufo#
Nair, Ramachandran D.
) into an Earth system model will require a highly scalable and accurate flux-form formulation of the dynamics
The martian mesosphere as revealed by CO2 cloud observations and General Circulation Modeling
Spiga, Aymeric
a rare dataset of mesospheric winds. We compare the mesospheric zonal winds pre- dicted by the model by the model. Ã? 2011 Elsevier Inc. All rights reserved. 1. Introduction While the formation of CO2 clouds observations on board Mars Global Surveyor (Clancy et al., 2004, 2007), and later confirmed by THEMIS-VIS (Mc
Linsenmeier, Manuel; Lucarini, Valerio
2014-01-01T23:59:59.000Z
We explore the implications of seasonal variability for the habitability of Earth-like planets as determined by the two parameters polar obliquity and orbital eccentricity. Commonly, the outer boundary of the habitable zone (HZ) is set by a completely frozen planet, or snowball state. Using a general circulation model coupled to a thermodynamic sea-ice model, our results show that seasonal variability can extend this outer limit of the HZ from 1.03 AU (no seasonal variability) to a maximum of 1.69 AU. Also the multistability property of planets close to the outer edge of the HZ is influenced by seasonal variability. Cold states extend far into the HZ for non-oblique planets. On highly oblique planets, cold states can also allow for habitable regions, which highlights the sufficient but not necessary condition of a warm climate state for habitability. While the effect of obliquity on the extent of the HZ is comparatively small on circular orbits, it becomes highly relevant on eccentric orbits. Our experiments ...
Cloud/Aerosol Parameterizations: Application and Improvement of General Circulation Models
Penner, Joyce
2012-06-30T23:59:59.000Z
One of the biggest uncertainties associated with climate models and climate forcing is the treatment of aerosols and their effects on clouds. The effect of aerosols on clouds can be divided into two components: The first indirect effect is the forcing associated with increases in droplet concentrations; the second indirect effect is the forcing associated with changes in liquid water path, cloud morphology, and cloud lifetime. Both are highly uncertain. This project applied a cloud-resolving model to understand the response of clouds under a variety of conditions to changes in aerosols. These responses are categorized according to the large-scale meteorological conditions that lead to the response. Meteorological conditions were sampled from various fields, which, together with a global aerosol model determination of the change in aerosols from present day to pre-industrial conditions, was used to determine a first order estimate of the response of global cloud fields to changes in aerosols. The response of the clouds in the NCAR CAM3 GCM coupled to our global aerosol model were tested by examining whether the response is similar to that of the cloud resolving model and methods for improving the representation of clouds and cloud/aerosol interactions were examined.
Multiple sea-ice states and abrupt MOC transitions in a general circulation ocean model
Ashkenazy, Yossi "Yosef"
represent present-day and cold-climate conditions. In each case the ocean model is initiated with both ice of about three degrees in latitude between the different runs is observed. The cold climate runs lead. Mirzayof Department of Solar Energy and Environmental Physics, BIDR, Ben-Gurion University, 84990 Midreshet
Circulation Models Alan M. Haywood a, , Mark A. Chandler b , Paul J. Valdes c , Ulrich Salzmann d , Daniel J set of Piacenzian Stage land cover [Salzmann, U., Haywood, A.M., Lunt, D.J., Valdes, P.J., Hill, D intervals in Earth History (e.g. Kutzbach and Otto-Bliesner, 1982; Barron and Washington, 1982; Valdes
On the Wind Power Input to the Ocean General Circulation
Zhai, Xiaoming
The wind power input to the ocean general circulation is usually calculated from the time-averaged wind products. Here, this wind power input is reexamined using available observations, focusing on the role of the synoptically ...
Integration of Different Wave Forcing Formulations with Nearshore Circulation Models
Sharma, Abhishek
2012-02-14T23:59:59.000Z
Wave-induced circulation in general coastal environments is simulated by coupling two widely-used finite-element models, namely, a refraction-diffraction-reflection model based on the elliptic mild-slope equation, and a two-dimensional (depth...
Dansereau, Véronique
2012-01-01T23:59:59.000Z
Interactions between the ocean circulation in sub-ice shelf cavities and the overlying ice shelf have received considerable attention in the context of observed changes in flow speeds of marine ice sheets around Antarctica. ...
Stachnik, Justin Paul
2013-03-25T23:59:59.000Z
This dissertation presents a series of work related to the representation of the Hadley circulation (HC) in atmospheric reanalyses and general circulation models (GCMs), with connections to the underlying tropical and subtropical cloud systems...
Rao, Samrat
2015-01-01T23:59:59.000Z
An atmospheric general circulation model (AGCM) with idealized and complete physics has been used to evaluate the Tropical Easterly Jet (TEJ) jet. In idealized physics, the role of upper tropospheric friction has been found to be important in getting realistic upper tropospheric zonal wind patterns in response to heating. In idealized physics, the location and strength of the TEJ as a response to Gill heating has been studied. Though the Gill model is considered to be widely successful in capturing the lower tropospheric response, it is found to be inadequate in explaining the location and strength of the upper level TEJ. Heating from the Gill model and realistic upper tropospheric friction does not lead to the formation of a TEJ.
Houze, Jr., Robert A. [University of Washington Dept. of Atmospheric Sciences
2013-11-13T23:59:59.000Z
We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.
On the Wind Power Input to the Ocean General Circulation XIAOMING ZHAI
Johnson, Helen
On the Wind Power Input to the Ocean General Circulation XIAOMING ZHAI Atmospheric, Oceanic January 2012, in final form 3 May 2012) ABSTRACT The wind power input to the ocean general circulation is usually calculated from the time-averaged wind products. Here, this wind power input is reexamined using
Power-Law and Long-Memory Characteristics of the Atmospheric General Circulation DMITRY I. VYUSHIN memory'' or ``power-law'' model. Such a model fits a temporal spectrum to a single power-law function, which thereby accumulates more power at lower frequencies than an AR1 fit. In this study, several power
V. Ramaswamy; L. J. Donner; J-C. Golaz; S. A. Klein
2010-06-17T23:59:59.000Z
This report briefly summarizes the progress made by ARM postdoctoral fellow, Yanluan Lin, at GFDL during the period from October 2008 to present. Several ARM datasets have been used for GFDL model evaluation, understanding, and improvement. This includes a new ice fall speed parameterization with riming impact and its test in GFDL AM3, evaluation of model cloud and radiation diurnal and seasonal variation using ARM CMBE data, model ice water content evaluation using ARM cirrus data, and coordination of the TWPICE global model intercomparison. The work illustrates the potential and importance of ARM data for GCM evaluation, understanding, and ultimately, improvement of GCM cloud and radiation parameterizations. Future work includes evaluation and improvement of the new dynamicsPDF cloud scheme and aerosol activation in the GFDL model.
A frequency domain finite element model for tidal circulation
Westerink, Joannes J.
1985-01-01T23:59:59.000Z
A highly efficient finite element model has been developed for the numerical prediction of depth average circulation within small scale embayments which are often characterized by irregular boundaries and bottom topography.
1950 B i M d l 1960 General Circulation
Rannacher, Rolf
AFA 2001 TAR 2000 Earth System Models (ESMs) 2014 ARS Climate Research Meteo- rology Climate Change Atmosphere Ocean Models (AOGCMs) 1979 Charney Report 1990 FAR 1995 SAR 2007 AFA 2001 TAR 2000 Earth System Models (ESMs) 2014 ARS Climate Research Meteo- rology Climate Change Science and Policy 1 Cl Re Meteo
Testing Components of New Community Isopycnal Ocean Circulation Model
Bryan, Kirk
2008-05-09T23:59:59.000Z
The ocean and atmosphere are both governed by the same physical laws and models of the two media have many similarities. However, there are critical differences that call for special methods to provide the best simulation. One of the most important difference is that the ocean is nearly opaque to radiation in the visible and infra-red part of the spectrum. For this reason water mass properties in the ocean are conserved along trajectories for long distances and for long periods of time. For this reason isopycnal coordinate models would seem to have a distinct advantage in simulating ocean circulation. In such a model the coordinate surfaces are aligned with the natural paths of near adiabatic, density conserving flow in the main thermocline. The difficulty with this approach is at the upper and lower boundaries of the ocean, which in general do not coincide with density surfaces. For this reason hybrid coordinate models were proposed by Bleck and Boudra (1981) in which Cartesian coordinates were used near the ocean surface and isopycnal coordinates were used in the main thermocline. This feature is now part of the HICOM model (Bleck, 2002).
Govind, R. [Cincinnati Univ., OH (United States). Dept. of Chemical Engineering
1993-03-20T23:59:59.000Z
It was found that there was a strong dependence of the density profile on the secondary air injection location and that there was a pronounced solid separation from the conveying gas, due to the swirl motion. Furthermore, the swirl motion generated strong internal circulation patterns and higher slip velocities than in the case of nonswirl motion as in an ordinary circulating fluidized bed. Radial solids flux profiles were measured at different axial locations. The general radial profile in a swirling circulating fluidized bed indicated an increased downward flow of solids near the bed walls, and strong variations in radial profiles along the axial height. For swirl numbers less than 0.9, which is typical for swirling circulating fluidized beds, there is no significant increase in erosion due to swirl motion inside the bed. Pending further investigation of swirl motion with combustion, at least from our cold model studies, no disadvantages due to the introduction of swirl motion were discovered.
Allan, Richard P.
Environment Model (HiGEM), suggest that including mineral dust radiative effects removes this bias21 June 2007, although differences in cloud cover also impact the modelGERB differences. Copyright c 2011 A Examination of long-wave radiative bias in general circulation models over North Africa during
Optimal control of CPR procedure using hemodynamic circulation model
Lenhart, Suzanne M. (Knoxville, TN); Protopopescu, Vladimir A. (Knoxville, TN); Jung, Eunok (Seoul, KR)
2007-12-25T23:59:59.000Z
A method for determining a chest pressure profile for cardiopulmonary resuscitation (CPR) includes the steps of representing a hemodynamic circulation model based on a plurality of difference equations for a patient, applying an optimal control (OC) algorithm to the circulation model, and determining a chest pressure profile. The chest pressure profile defines a timing pattern of externally applied pressure to a chest of the patient to maximize blood flow through the patient. A CPR device includes a chest compressor, a controller communicably connected to the chest compressor, and a computer communicably connected to the controller. The computer determines the chest pressure profile by applying an OC algorithm to a hemodynamic circulation model based on the plurality of difference equations.
Arctic sea ice velocity field: General circulation and turbulent-like fluctuations
Boyer, Edmond
Arctic sea ice velocity field: General circulation and turbulent-like fluctuations P. Rampal,1,2 J the Arctic sea ice velocity field as the superposition of a mean field and fluctuations. We study how subtracting the mean field, are analyzed in terms of diffusion properties. Although the Arctic sea ice cover
DÃ¶Ã¶s, Kristofer
that the cycle has a peak transport of 428 Sv (Sv [ 109 kg s21 ). The thermodynamic cycle encapsulates a globally. Introduction The atmospheric general circulation forms as a re- sponse to differential solar heating (solar heating and ocean heat fluxes) vary. El Ni~noÂSouthern Oscillation (ENSO) is one of the dominant
MODELING CYCLIC WAVES OF CIRCULATING T CELLS IN AUTOIMMUNE DIABETES
Mahaffy, Joseph M.
MODELING CYCLIC WAVES OF CIRCULATING T CELLS IN AUTOIMMUNE DIABETES JOSEPH M. MAHAFFY AND LEAH EDELSTEIN-KESHET Abstract. Type 1 diabetes (T1D) is an autoimmune disease in which immune cells, notably T diabetes result once a large enough fraction of these beta cells have been destroyed. Recent investigation
RHP: HOW CLIMATE MODELS GAIN AND EXERCISE How Climate Models Gain and Exercise Authority
Hulme, Mike
-dimensional models, intermediate complexity models, general circulation models, and Earth system models. 2 www
MacCready, Parker
Seasonal and Interannual Variability in the Circulation of Puget Sound, Washington: A Box Model A prognostic, time-dependent box model of circulation in Puget Sound, Washington is used to study seasonal circulation dans le détroit de Puget, dans l'État de Washington, pour étudier les variations saisonnières et
Decadal changes in the equatorial Pacific circulation
Urizar, S. Cristina
2002-01-01T23:59:59.000Z
An ocean general circulation model with data assimilation is used to analyze the decadal changes in the tropical Pacific Ocean circulation. Results indicate that the variability in the Equatorial Undercurrent (EUC) and subtropical cells (STC) have...
Modeling the 19982003 summer circulation and thermal structure in Lake Michigan
Modeling the 19982003 summer circulation and thermal structure in Lake Michigan Dmitry Beletsky,1 to Lake Michigan on a 2 km grid for 6 consecutive years to study interannual variability of summer. Circulation in southern Lake Michigan appears to be more variable than circulation in northern Lake Michigan
Chung, Y.G.; Lee, G.B.; Bang, S.Y. [Korea Electric Power Research Institute, 103-16 Munji-Dong, Yuseong-Gu, Daejeon 305-380 (Korea, Republic of); Choi, S.B.; Lee, S.U. [Korea Hydro and Nuclear Power Co., LTD, 167 Samseong-Dong, Gangnam-Gu, Seoul 135-791 (Korea, Republic of); Yoon, J.H. [Research Institute of Applied Physics, Kyushu University, 6-1 Kasuga-kouen, Kasuga, Fukuoka, 816-8580 (Japan); Nam, S.Y.; Lee, H.R. [GeoSystem Research Corporation, 306 Hanlim Human Town, 1-40 Geumjeong-Dong, Gunpo-City, Gyeonggi-Do 435-050 (Korea, Republic of)
2006-07-01T23:59:59.000Z
Recently, three-dimensional models have been used for aquatic dispersion of radioactive effluents in relation to nuclear power plant siting based on the Notice No. 2003-12 'Guideline for investigating and assessing hydrological and aquatic characteristics of nuclear facility site' of the Ministry of Science and Technology (MOST) in Korea. Several nuclear power plants have been under construction or planed, which are Shin-Kori Unit 1 and 2, Shin-Wolsong Unit 1 and 2, and Shin-Ulchin Unit 1 and 2. For assessing the aquatic dispersion of radionuclides released from the above nuclear power plants, it is necessary to know the coastal currents around sites which are affected by circulation of East Sea. In this study, a three dimensional hydrodynamic model for the circulation of the East Sea of Korea has been developed as the first phase, which is based on the RIAMOM (Research Institute of Applied Mechanics' Ocean Model, Kyushu University, Japan). The model uses the primitive equation with hydrostatic approximation, and uses Arakawa-B grid system horizontally and Z coordinate vertically. Model domain is 126.5 deg. E to 142.5 deg. E of east longitude and 33 deg. N and 52 deg. N of the north latitude. The space of the horizontal grid was 1/12 deg. to longitude and latitude direction and vertical level was divided to 20. This model uses Generalized Arakawa Scheme, Slant Advection, and Mode-Splitting Method. The input data were from JODC (Japan Oceanographic Data Center), KNFRDI (Korea National Fisheries Research and Development Institute), and ECMWF (European Center for Medium-Range Weather Forecasts). The modeling results are in fairly good agreement with schematic patterns of the surface circulation in the East Sea/Japan Sea. The local current model and aquatic dispersion model of the coastal region will be developed as the second phase. The oceanic dispersion experiments will be also carried out by using ARGO Drifter around a nuclear power plant site. (authors)
A numerical ocean circulation model of the Norwegian and Greenland Seas
Stevens, David
A numerical ocean circulation model of the Norwegian and Greenland Seas DAVID P STEVENS School of the Norwegian and Greenland Seas are investigated using a three-dimensional primitive equation ocean circulation and seasonally varying wind and thermohalme forcing. The connections of the Norwegian and Greenland Seas
Posters A Stratiform Cloud Parameterization for General Circulation Models
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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:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations71 Posters A51
Posters Comparison Between General Circulation Model Simulation and Central Equatorial
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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:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations71
Posters Treatment of Cloud Radiative Effects in General Circulation Models
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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:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations7197117313735
Evaluation of cirrus statistics produced by general circulation models
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. Category UC-l 1, 13Evacuation248 Evaluation of Wax
Testing Linear Diagnostics of Ensemble Performance on a Simplified Global Circulation Model
Nelson, Ethan
2011-04-21T23:59:59.000Z
is inherently flow dependent and that the ensemble predicts potential patterns of forecast errors more reliably than the magnitudes of the errors. A low-resolution global circulation model is implemented to calculate linear diagnostics in the vector space...
Solution of the multiple traveling salesman problem with a circulation network model
Forester, Ronald Ray
1983-01-01T23:59:59.000Z
SOLUTION OF THE MULTIPLE TRAVELING SALESMAN PROBLEM WITH A CIRCULATION NETWORK MODEL A Thesis by RONALD RAY FORESTER Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1983 Major Subject: Industrial Engineering SOLUTION OF THE MULTIPLE TRAVELING SALESMAN PROBLEM WITH A CIRCULATION NETWORK MODEL A Thesis by RONALD RAY FORESTER Approved as to style and content by: erto are&a- saz...
Development of the Great Lakes Ice-circulation Model (GLIM): Application to Lake Erie in 20032004
Development of the Great Lakes Ice-circulation Model (GLIM): Application to Lake Erie in 2003: Received 4 May 2009 Accepted 30 November 2009 Communicated by Dr. Ram Yerubandi Index words: Coupled Ice-Ocean Model Ice modeling Lake ice cover Ice thickness Ice speed Lake surface temperature Great Lakes Lake Erie
Modeling Timed Concurrent Systems using Generalized Ultrametrics
Modeling Timed Concurrent Systems using Generalized Ultrametrics Xiaojun Liu Eleftherios Matsikoudis Edward A. Lee Electrical Engineering and Computer Sciences University of California at Berkeley to lists, requires prior specific permission. #12;Modeling Timed Concurrent Systems using Generalized
Model-free adaptive control of supercritical circulating fluidized-bed boilers
Cheng, George Shu-Xing; Mulkey, Steven L
2014-12-16T23:59:59.000Z
A novel 3-Input-3-Output (3.times.3) Fuel-Air Ratio Model-Free Adaptive (MFA) controller is introduced, which can effectively control key process variables including Bed Temperature, Excess O2, and Furnace Negative Pressure of combustion processes of advanced boilers. A novel 7-input-7-output (7.times.7) MFA control system is also described for controlling a combined 3-Input-3-Output (3.times.3) process of Boiler-Turbine-Generator (BTG) units and a 5.times.5 CFB combustion process of advanced boilers. Those boilers include Circulating Fluidized-Bed (CFB) Boilers and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.
the fall cooling, and finally, an overturn in the late fall. Large-scale circulation patterns tend significant progress in hydrodynamic modeling of short- term hydrodynamic processes in the Great Lakes [Schwab was virtually non- existent until the implementation of the Great Lakes Forecast- ing System (GLFS) in the early
DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL
Tandon, Amit
DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL developed to automatically detect, locate and track mesoscale eddies spatially and temporally. Using an invaluable tool to assess mesoscale oceanic features. Key Words Scientific Visualization, Eddy Detection
Follows, Mick
Evaluating carbon sequestration efficiency in an ocean circulation model by adjoint sensitivity the application of the adjoint method to develop three-dimensional maps of carbon sequestration efficiency. Sequestration efficiency (the percentage of carbon injected at a continuous point source that remains
Modeling wind-driven circulation during the March 1998 sediment resuspension event in Lake Michigan
Modeling wind-driven circulation during the March 1998 sediment resuspension event in Lake Michigan Michigan to simulate hydrodynamic conditions during the March 1998 sediment resuspension event in southern resuspension Citation: Beletsky, D., D. J. Schwab, P. J. Roebber, M. J. McCormick, G. S. Miller, and J. H
A Continuous ` \\Gamma oe Vertical Coordinate for a Baroclinic Model of the Atmospheric Circulation
Drake, John B.
meteorolgoical coordinate system is developed which can support a continuous isentropic oe vertical coordinate and boundary layer approximations were addressed by the introduction of a hybrid (patched) model [15]. By use analysis [14, 8]. The effects of heating on the circulation are most clearly seen with the isentropic
The effects of North Atlantic SST and sea-ice anomalies on the winter circulation in CCM3.
Magnusdottir, Gudrun
1 The effects of North Atlantic SST and sea-ice anomalies on the winter circulation in CCM3. Part of experiments with an atmospheric general circulation model, Community Climate Model Version 3 (CCM3). As shown
Paris-Sud XI, Université de
Central South Pacific thermocline water circulation from a high-resolution ocean model validated. Introduction [2] Most South Pacific Ocean studies have been focused on its western or eastern part, leaving 12 January 2009; accepted 28 January 2009; published 13 May 2009. [1] The oceanic circulation
40 greater influence and penetration of deep water formed in 41 the Southern Ocean [e.g., Oppo2 Ocean circulation at the Last Glacial Maximum: 3 A combined modeling and magnetic proxy (NADW) is an important component of the ocean thermohaline 7 circulation, but debate exists over
Study of natural circulation in a VHTR after a LOFA using different turbulence models
Yu-Hsin Tung; Yuh-Ming Ferng; Richard W. Johnson; Ching-Chang Chieng
2013-10-01T23:59:59.000Z
Natural convection currents in the core are anticipated in the event of the failure of the gas circulator in a prismatic gas-cooled very high temperature reactor (VHTR). The paths that the helium coolant takes in forming natural circulation loops and the effective heat transport are of interest. The heated flow in the reactor core is turbulent during normal operating conditions and at the beginning of the LOFA with forced convection, but the flow may significantly be slowed down after the event and laminarized with mixed convection. In the present study, the potential occurrence and effective heat transport of natural circulation are demonstrated using computational fluid dynamic (CFD) calculations with different turbulence models as well as laminar flow. Validations and recommendation on turbulence model selection are conducted. The study concludes that large loop natural convection is formed due to the enhanced turbulence levels by the buoyancy effect and the turbulent regime near the interface of upper plenum and flow channels increases the flow resistance for channel flows entering upper plenum and thus less heat can be removed from the core than the prediction by laminar flow assumption.
Cheon, Woo Geunn
2009-05-15T23:59:59.000Z
This dissertation discusses a linkage between the Southern Ocean (SO) winds and the global ocean circulation in the framework of a coarse-resolution global ocean general circulation model coupled to a sea-ice model. In addition to reexamination...
Ma, Po-Lun; Rasch, Philip J.; Wang, Hailong; Zhang, Kai; Easter, Richard C.; Tilmes, S.; Fast, Jerome D.; Liu, Xiaohong; Yoon, Jin-Ho; Lamarque, Jean-Francois
2013-05-28T23:59:59.000Z
Current climate models generally under-predict the surface concentration of black carbon (BC) in the Arctic due to the uncertainties associated with emissions, transport, and removal. This bias is also present in the Community Atmosphere Model Version 5.1 (CAM5). In this study, we investigate the uncertainty of Arctic BC due to transport processes simulated by CAM5 by configuring the model to run in an “offline mode” in which the large-scale circulations are prescribed. We compare the simulated BC transport when the offline model is driven by the meteorology predicted by the standard free-running CAM5 with simulations where the meteorology is constrained to agree with reanalysis products. Some circulation biases are apparent: the free-running CAM5 produces about 50% less transient eddy transport of BC than the reanalysis-driven simulations, which may be attributed to the coarse model resolution insufficient to represent eddies. Our analysis shows that the free-running CAM5 reasonably captures the essence of the Arctic Oscillation (AO), but some discernable differences in the spatial pattern of the AO between the free-running CAM5 and the reanalysis-driven simulations result in significantly different AO modulation of BC transport over Northeast Asia and Eastern Europe. Nevertheless, we find that the overall climatological circulation patterns simulated by the free-running CAM5 generally resembles those from the reanalysis products, and BC transport is very similar in both simulation sets. Therefore, the simulated circulation features regulating the long-range BC transport is unlikely the most important cause of the large under-prediction of surface BC concentration in the Arctic.
Khangaonkar, Tarang; Yang, Zhaoqing; Kim, Tae Yun; Roberts, Mindy
2011-07-20T23:59:59.000Z
Through extensive field data collection and analysis efforts conducted since the 1950s, researchers have established an understanding of the characteristic features of circulation in Puget Sound. The pattern ranges from the classic fjordal behavior in some basins, with shallow brackish outflow and compensating inflow immediately below, to the typical two-layer flow observed in many partially mixed estuaries with saline inflow at depth. An attempt at reproducing this behavior by fitting an analytical formulation to past data is presented, followed by the application of a three-dimensional circulation and transport numerical model. The analytical treatment helped identify key physical processes and parameters, but quickly reconfirmed that response is complex and would require site-specific parameterization to include effects of sills and interconnected basins. The numerical model of Puget Sound, developed using unstructured-grid finite volume method, allowed resolution of the sub-basin geometric features, including presence of major islands, and site-specific strong advective vertical mixing created by bathymetry and multiple sills. The model was calibrated using available recent short-term oceanographic time series data sets from different parts of the Puget Sound basin. The results are compared against (1) recent velocity and salinity data collected in Puget Sound from 2006 and (2) a composite data set from previously analyzed historical records, mostly from the 1970s. The results highlight the ability of the model to reproduce velocity and salinity profile characteristics, their variations among Puget Sound subbasins, and tidally averaged circulation. Sensitivity of residual circulation to variations in freshwater inflow and resulting salinity gradient in fjordal sub-basins of Puget Sound is examined.
Superconformal generalizations of the Starobinsky model
Kallosh, Renata; Linde, Andrei, E-mail: kallosh@stanford.edu, E-mail: alinde@stanford.edu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA 94305 (United States)
2013-06-01T23:59:59.000Z
We find a way to represent the Starobinsky model in terms of a simple conformally invariant theory with spontaneous symmetry breaking. We also present a superconformal theory, which, upon spontaneous breaking of the superconformal symmetry, provides a consistent supergravity generalization of the Starobinsky model.
Dynamical models with a general anisotropy profile
M. Baes; E. Van Hese
2007-05-28T23:59:59.000Z
Both numerical simulations and observational evidence indicate that the outer regions of galaxies and dark matter haloes are typically mildly to significantly radially anisotropic. The inner regions can be significantly non-isotropic, depending on the dynamical formation and evolution processes. In an attempt to break the lack of simple dynamical models that can reproduce this behaviour, we explore a technique to construct dynamical models with an arbitrary density and an arbitrary anisotropy profile. We outline a general construction method and propose a more practical approach based on a parameterized anisotropy profile. This approach consists of fitting the density of the model with a set of dynamical components, each of which have the same anisotropy profile. Using this approach we avoid the delicate fine-tuning difficulties other fitting techniques typically encounter when constructing radially anisotropic models. We present a model anisotropy profile that generalizes the Osipkov-Merritt profile, and that can represent any smooth monotonic anisotropy profile. Based on this model anisotropy profile, we construct a very general seven-parameter set of dynamical components for which the most important dynamical properties can be calculated analytically. We use the results to look for simple one-component dynamical models that generate simple potential-density pairs while still supporting a flexible anisotropy profile. We present families of Plummer and Hernquist models in which the anisotropy at small and large radii can be chosen as free parameters. We also generalize these two families to a three-parameter family that self-consistently generates the set of Veltmann potential-density pairs. (Abridged...)
Abstract polymer models with general pair interactions
Aldo Procacci
2008-11-26T23:59:59.000Z
A convergence criterion of cluster expansion is presented in the case of an abstract polymer system with general pair interactions (i.e. not necessarily hard core or repulsive). As a concrete example, the low temperature disordered phase of the BEG model with infinite range interactions, decaying polynomially as $1/r^{d+\\lambda}$ with $\\lambda>0$, is studied.
GENERALIZED LINEAR MODELS WITH REGULARIZATION A DISSERTATION
Hastie, Trevor
GENERALIZED LINEAR MODELS WITH REGULARIZATION A DISSERTATION SUBMITTED TO THE DEPARTMENT Park 2006 All Rights Reserved ii #12;I certify that I have read this dissertation and that, in my opinion, it is fully adequate in scope and quality as a dissertation for the degree of Doctor
Single-Column Modeling A Stratiform Cloud Parameterization for General Circulation Models
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:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9Morgan McCorkleSingin' in the RainC.J. Somerville andA
Sensitivities of zonal mean atmospheric circulation to SST warming in an aquaplanet model
Chen, Gang
] What causes these circulation changes is not fully understood. Since global warming and El NiÃ±o, storm tracks, or the boundaries of Hadley cell circulations under global warming [e.g., Yin, 2005 and the latitude of surface westerlies in response to El NiÃ±o versus global warming [Lu et al., 2008; Chen et al
Quasi-steady model for predicting temperature of aqueous foams circulating in geothermal wellbores
Blackwell, B.F.; Ortega, A.
1983-01-01T23:59:59.000Z
A quasi-steady model has been developed for predicting the temperature profiles of aqueous foams circulating in geothermal wellbores. The model assumes steady one-dimensional incompressible flow in the wellbore; heat transfer by conduction from the geologic formation to the foam is one-dimensional radially and time-dependent. The vertical temperature distribution in the undisturbed geologic formation is assumed to be composed of two linear segments. For constant values of the convective heat-transfer coefficient, a closed-form analytical solution is obtained. It is demonstrated that the Prandtl number of aqueous foams is large (1000 to 5000); hence, a fully developed temperature profile may not exist for representative drilling applications. Existing convective heat-transfer-coefficient solutions are adapted to aqueous foams. The simplified quasi-steady model is successfully compared with a more-sophisticated finite-difference computer code. Sample temperature-profile calculations are presented for representative values of the primary parameters. For a 5000-ft wellbore with a bottom hole temperature of 375{sup 0}F, the maximum foam temperature can be as high as 300{sup 0}F.
None
2005-07-01T23:59:59.000Z
This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, {musubs} = 5.34{epsisubs}, ({espisubs} is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to acount for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from a 7.5-cm-ID CFB riser at the Illinois Institute of Technology and data from a 20.0-cm-ID CFB riser at the Particulate Solid Research, Inc., facility. This research aims at modeling the removal of hydrogen sulfide from hot coal gas using zinc oxide as the sorbent in a circulating fluidized bed and in the process indentifying the parameters that affect the performance of the sulfidation reactor. Two different gas-solid reaction models, the unreacted shrinking core (USC) and the grain model were applied to take into account chemical reaction resistances. Also two different approaches were used to affect the hydrodynamics of the process streams. The first model takes into account the effect of micro-scale particle clustering by adjusting the gas-particle drag law and the second one assumes a turbulent core with pseudo-steady state boundary condition at the wall. A comparison is made with experimental results.
Kataria, Tiffany; Fortney, Jonathan J; Stevenson, Kevin B; Line, Michael R; Kreidberg, Laura; Bean, Jacob L; Désert, Jean-Michel
2014-01-01T23:59:59.000Z
The hot Jupiter WASP-43b has now joined the ranks of transiting hot Jupiters HD 189733b and HD 209458b as an exoplanet with a large array of observational constraints on its atmospheric properties. Because WASP-43b receives a similar stellar flux as HD 209458b but has a rotation rate 4 times faster and a much higher gravity, studying WASP-43b serves as a test of the effect of rotation rate and gravity on the circulation when stellar irradiation is held approximately constant. Here we present 3D atmospheric circulation models of WASP-43b using the SPARC/MITgcm, a coupled radiation and circulation model, exploring the effects of composition, metallicity, and frictional drag. We find that the circulation regime of WASP-43b is not unlike other hot Jupiters, with equatorial superrotation that yields an eastward-shifted hotspot and large day-night temperature variations (~600 K at photospheric pressures). We then compare our model results to observations from Stevenson et al. which utilize HST/WFC3 to collect spect...
Xie, L.; Pietrafesa, L.J.; Raman, S.
1997-03-18T23:59:59.000Z
Interactions between surface winds and ocean currents over an east-coast continental shelf are studied using a simple mathematical model. The model physics include cross-shelf advection of sea surface temperature (SST) by Ekman drift, upwelling due to Ekman transport divergence, differential heating of the low-level atmosphere by a cross-shelf SST gradient, and the Coriolis effect. Additionally, the effects of diabatic cooling of surface waters due to air-sea heat exchange and of the vertical density stratification on the thickness of the upper ocean Ekman layer are considered. The model results are qualitatively consistent with observed wind-driven coastal ocean circulation and surface wind signatures induced by SST. This simple model also demonstrates that two-way air-sea interaction plays a significant role in the subtidal frequency variability of coastal ocean circulation and mesoscale variability of surface wind fields over coastal waters.
Belucz, Bernadett; Forgacs-Dajka, Emese
2015-01-01T23:59:59.000Z
Babcock-Leighton type solar dynamo models with single-celled meridional circulation are successful in reproducing many solar cycle features. Recent observations and theoretical models of meridional circulation do not indicate a single-celled flow pattern. We examine the role of complex multi-cellular circulation patterns in a Babcock-Leighton solar dynamo in advection- and diffusion-dominated regimes. We show from simulations that presence of a weak, second, high-latitude reverse cell speeds up the cycle and slightly enhances the poleward branch in butterfly diagram, whereas the presence of a second cell in depth reverses the tilt of butterfly wing to an anti-solar type. A butterfly diagram constructed from middle of convection zone yields a solar-like pattern, but this may be difficult to realize in the Sun because of magnetic buoyancy effects. Each of the above cases behaves similarly in higher and lower magnetic diffusivity regimes. However, our dynamo with a meridional circulation containing four cells in...
Interactions between the Indonesian Throughflow and circulations in the Indian and Pacific Oceans
Jensen, Tommy
Interactions between the Indonesian Throughflow and circulations in the Indian and Pacific Oceans with the Indonesian Throughflow (IT), particularly concerning subsurface currents in the Pacific Ocean, are studied model (LOM), both confined to the Indo-Pacific basin; and a global, ocean general circulation model
Mechanisms for Tropical Tropospheric Circulation Change in Response to Global Warming*
Xie, Shang-Ping
Mechanisms for Tropical Tropospheric Circulation Change in Response to Global Warming* JIAN MA change in global warming is studied by comparing the response of an atmospheric general circulation model globally in response to SST warming. A diagnostic framework is developed based on a linear baroclinic model
Efficient inference in general semiparametric regression models
Maity, Arnab
2009-05-15T23:59:59.000Z
. Note that (2.17) means that the non-zero Y-data within an indi- vidual marginally have the same mean R T i ? 2 + ?(Z i ), variance ? 2 + ? 2 u2 and common covariance ? 2 u2 . II.4.2.3. Likelihood Function The collection of parameters is B, consisting... .............................. 4 II.1. Introduction ......................... 4 II.2. Semiparametric Models with a Single Component ..... 8 II.2.1. Main Results .................... 8 II.2.2. General Functions of the Response and Double- Robustness ..................... 11 II.3...
Atlantic Ocean circulation at the last glacial maximum : inferences from data and models
Dail, Holly Janine
2012-01-01T23:59:59.000Z
This thesis focuses on ocean circulation and atmospheric forcing in the Atlantic Ocean at the Last Glacial Maximum (LGM, 18-21 thousand years before present). Relative to the pre-industrial climate, LGM atmospheric CO? ...
Model for Energy Supply System Alternatives and their General...
System Alternatives and their General Environmental Impacts (MESSAGE) (Redirected from Model for Energy Supply System Alternatives and their General Environmental Impacts) Jump to:...
Atmospheric Circulation Response to an Instantaneous Doubling of Carbon Dioxide. Part I: Model Experiments and Transient Thermal Response in the Troposphere* YUTIAN WU Department of Applied Physics (CO2) by looking into the transient step-by-step adjustment of the circulation. The transient
Sherwood, Steven
a significant weakening(in NCW) or rearrangement(in NCWP) of the Walker circulation. Zonal mean cloud cover release is a nonlocal transfer of heat from the oceans to the atmosphere,while the radiative effects an atmosphericgeneral circulation model to radiative forcing of tropical clouds Steven C. Sherwood,· V. Ramanathan,·,2
New model for nucleon generalized parton distributions
Radyushkin, Anatoly V. [JLAB, Newport News, VA (United States)
2014-01-01T23:59:59.000Z
We describe a new type of models for nucleon generalized parton distributions (GPDs) H and E. They are heavily based on the fact nucleon GPDs require to use two forms of double distribution (DD) representations. The outcome of the new treatment is that the usual DD+D-term construction should be amended by an extra term, {xi} E{sub +}{sup 1} (x,{xi}) which has the DD structure {alpha}/{beta} e({beta},{alpha}, with e({beta},{alpha}) being the DD that generates GPD E(x,{xi}). We found that this function, unlike the D-term, has support in the whole -1 <= x <= 1 region. Furthermore, it does not vanish at the border points |x|={xi}.
antigen circulating anodic: Topics by E-print Network
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introduced to study the role of ocean circulation on the mean climate of the coupled ... Marshall, John C. 409 Upward Shift of the Atmospheric General Circulation under Global...
alkaline fluid circulation: Topics by E-print Network
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introduced to study the role of ocean circulation on the mean climate of the coupled ... Marshall, John C. 459 Upward Shift of the Atmospheric General Circulation under Global...
EXTENSIONS OF GENERALIZED LINEAR MODELING APPROACH TO STOCHASTIC WEATHER GENERATORS
Katz, Richard
weather) -- Software R open source statistical programming language: Function glm "Family;(2) Generalized Linear Models Statistical Framework -- Multiple Regression Analysis (Linear model or LM) Response
Llamas Vidales, Jose Ricardo
2009-01-01T23:59:59.000Z
The liver regulates a myriad of vital functions including bile acid synthesis, hepatobiliary circulation, cholesterol homeostasis, drug metabolism, etc. This thesis focuses on the use of a 3D in vitro model of liver to ...
Discriminating robust and non-robust atmospheric circulation responses to global warming
Discriminating robust and non-robust atmospheric circulation responses to global warming Michael response to global warming in a set of atmospheric general circulation models (AGCMs) is investigated. The global-warmed climate is forced by a global pattern of warmed ocean surface temperatures
Comparative Evaluation of Generalized River/Reservoir System Models
Wurbs, Ralph A.
This report reviews user-oriented generalized reservoir/river system models. The terms reservoir/river system, reservoir system, reservoir operation, or river basin management "model" or "modeling system" are used synonymously to refer to computer...
Generalized models and benchmarks for channel coordination
Toptal, Aysegul
2004-09-30T23:59:59.000Z
. . . . . . . . . . . . . . . . . . . . . . . . . . . 39 III INTEGRATED PURE INVENTORY PROBLEM WITH DE- TERMINISTIC AND CONSTANT DEMAND . . . . . . . . . . 41 III.1. Notation and Problem Formulation . . . . . . . . . . . . 42 III.2. Model I: A Model with Explicit Inbound Costs . . . . . . 45 III.3. Model... WITH DETERMINISTIC AND CONSTANT DEMAND . . . . . . . . . . . . . . . . . . . 76 IV.1. A Comparative Analysis of Centralized and Decentral- ized Models in Goyal (1976) . . . . . . . . . . . . . . . . 78 IV.2. Decentralized Solutions for Model I and Model II...
Aluminium in an ocean general circulation model compared with the West Atlantic Geotraces cruises
Stoffelen, Ad
and Duce, 1987; Measures et al., 2005; Orians and Bruland, 1986). When dust enters the ocean, a part of its
Sun, Dezheng
that the bias is likely linked to a weaker relationship between the short-wave cloud forcing is a long-standing tropical bias in the CGCMs. The early hypotheses attribute this problem to the errors;4 errors may induce excessive equatorial upwelling upon coupling. The surface heating from the atmospheric
Multiple sea-ice states and abrupt MOC transitions in a general circulation ocean model
Tziperman, Eli
different land ice distributions represent present-day and cold-climate conditions. In each case the ocean is observed. The cold climate runs lead to meridional sea-ice extents that are different by up to four degrees. Y. Ashkenazy (&) Ã D. Mirzayof Department of Solar Energy and Environmental Physics, BIDR, Ben
Interactive chemistry in the Laboratoire de Meteorologie Dynamique general circulation model
Hourdin, Chez Frédéric
of soluble species. The global and annual mean methane (7.9 years) and methylchloroform (4.6 years) chemical chemical scheme representative of the background chemistry of the troposphere is considered. We derive rapid interhemispheric exchange times of 1.13 1.38 years and 0.700.82 years, based on surface
Towards explaining the Nd paradox using reversible scavenging in an ocean general circulation model
Khatiwala, Samar
of the rare earth element neodymium (Nd) has the potential to serve as water-mass tracer, because a,b , Sidney Hemming a,b , Robert F. Anderson a,b a Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA b Department of Earth and Environmental Sciences, Columbia
Quaas, Johannes
2010-01-01T23:59:59.000Z
such as cloud contamination or 3D radiation effects (Loebeffect relationship behind the aerosol – cloud/radiationradiation resulting in the “aerosol direct effect”. Hy- drophilic aerosols can serve as cloud
Quaas, Johannes
2010-01-01T23:59:59.000Z
such as cloud contamination or 3D radiation effects (Loebeffect relationship behind the aerosol – cloud/radiationradiation resulting in the “aerosol direct effect”. Hy- drophilic aerosols can serve as cloud
Model for Energy Supply System Alternatives and their General...
for Energy Supply System Alternatives and their General Environmental Impacts (MESSAGE) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Model for Energy Supply System...
Hospital Readmission in General Medicine Patients: A Prediction Model
2010-01-01T23:59:59.000Z
to the department of medicine as a screening tool forquality of care problems. Medicine. 2008;87:294–300. 3.Readmission in General Medicine Patients: A Prediction Model
A preliminary model of the circulating blood for use in radiation dose calculations
Hui, Tsz-Yik Edmond
1986-01-01T23:59:59.000Z
. , 1968) "Distribution of Dose in the Body for a Source of Gamma Rays Distributed Uniformly in an Organ, " Oak Rdige National Laboratory, Oak Ridge, TN, ORNL-4168. Folkow B ~ and Neil E ~ g 1971' Circulation (New York: Oxford University Press... Phantom, Oak Ridge National Laboratory, Oak Ridge, TN, ORNL-TM-2250. Wa84 Watson E. E. , Stabin M. G. and Bolch W. E. , 1984, HIRDOSE, Oak Ridge Associated Universities, Oak Ridge/ TN. 53 Va80 van Reenen O. R. , Lotter M. G. , Minnaar P. C. , Heyns A...
Li, Zhiyong; Chen, Chao; Luo, Hailiang; Zhang, Ye; Xue, Yaning [College of Architecture and Civil Engineering, Beijing University of Technology, Beijing (China)
2010-08-15T23:59:59.000Z
The aim of this paper is to establish the heat transfer model of all-glass vacuum tube collector used in forced-circulation solar water heating system. In this model, the simplified heat transfer of collector is composed of the natural convection in single glass tube and forced flow in manifold header. Thus the heat balance equation of water in single tube and the heat balance equation of water in manifold header have been established. The flow equation is also built by analyzing the friction and buoyancy in tube. Through solved these equations the relationship between the collector average temperature, the outlet temperature and natural convection flow rate have been obtained. From this relationship and energy balance equation of collector, the collector outlet temperature can be calculated. The validated experiments of this model were carried out in winter of Beijing. (author)
Vieira, Veronica M.; Weinberg, Janice M.; Webster, Thomas F.
2012-01-01T23:59:59.000Z
data using generalized additive modeling. BMC Public HealthTibshirani R: Generalized Additive Models. London: Chapmanapplication using generalized additive models. Int J Health
A General Model for Epistemic State Revision using Plausibility Measures
Liu, Weiru
A General Model for Epistemic State Revision using Plausibility Measures Jianbing Ma 1 and Weiru Liu1 Abstract. In this paper, we present a general revision model on epistemic states based on plausibility measures proposed by Fried- man and Halpern. We propose our revision strategy and give some
Intermediate-Generalized Chaplygin Gas inflationary universe model
Herrera, Ramon; Videla, Nelson
2013-01-01T23:59:59.000Z
An intermediate inflationary universe model in the context of a generalized Chaplygin gas is considered. For the matter we consider two different energy densities; a standard scalar field and a tachyon field, respectively. In general, we discuss the conditions of an inflationary epoch for these models. We also, use recent astronomical observations from Wilkinson Microwave Anisotropy Probe seven year data for constraining the parameters appearing in our models.
PRESERVING THE OCEAN CIRCULATION: IMPLICATIONS FOR CLIMATE POLICY
Morel, François M. M.
oceans. The posited collapse of this system could produce severe cooling in northwestern Europe, even collapse). This circulation system now warms north-western Europe and transports carbon dioxide to the deep when general global warming is in progress. In this paper we use a simple integrated assessment model
Orthogonal Forward Regression based on Directly Maximizing Model Generalization Capability
Chen, Sheng
for costly model evaluation. Index Terms -- orthogonal forward regression, structure identification, cross struc- ture construction process as a cost function in order to op- timize the model generalization introduces a construction algorithm for sparse kernel modelling using the leave-one-out test score also known
Double Generalized Linear Models: Approximate REML and Diagnostics
Smyth, Gordon K.
added com plication in a generalized linear model setting by adjusting the working vector and working the dispersion will be of direct interest in its own right, to identify the sources of variability
(CILER) , School of Natural Resources and Envi- ronment, University of Michigan, 4840 S State Road, Ann variations of ocean and sea ice circulation in the Beaufort and Chukchi Seas: A model-data fusion study Wang, M148108 USA 2 Department of Ocean Sciences, Tokyo University of Marine Science and Technology, 4
Zhong, L.
2014-01-01T23:59:59.000Z
DEALING WITH “BIG CIRCULATION FLOW RATE, SMALL TEMPERATURE DIFFERENCE” BASED ON VERIFIED DYNAMIC MODEL SIMULATIONS OF A HOT WATER DISTRICT HEATING SYSTEM Li Lian Zhong, Senior Sales Consultant, Danfoss Automatic Controls Management (Shanghai...) Co.,Ltd, Anshan, China ABSTRACT Dynamic models of an indirect hot water district heating system were developed based on the first principle of thermodynamics. The ideal model was verified by using measured operational data. The ideal...
Overturning and wind driven circulation in a low-order ocean-atmosphere model
van Veen, Lennaert
july 2002 Abstract A low-order ocean-atmosphere model is presented which combines coupling through heat exchange at the interface and wind stress forcing. The coupling terms are derived from the boundary conditions and the forcing terms of the constituents. Both the ocean and the atmosphere model are based
Early Warning Signals for Critical Transitions: A Generalized Modeling Approach
for early warning signals that integrates multiple sources of information and data about the system throughEarly Warning Signals for Critical Transitions: A Generalized Modeling Approach Steven J. Lade a previously published fisheries model. We regard our method as complementary to existing early warning signals
Correlation Effects in a Simple Stochastic Model of the Thermohaline Circulation
Monahan, Adam Hugh
. monahana@uvic.ca August 8, 2002 Present Address: School of Earth and Ocean Sciences, University of Victoria, P.O. Box 3055 STN CSC, Victoria BC, Canada, V8P 5C2 1 #12;Abstract A simple model
Lyapunov Exponents of a Simple Stochastic Model of the Thermally and Wind-Driven Ocean Circulation
Monahan, Adam Hugh
August 8, 2002 Present Address: School of Earth and Ocean Sciences, University of Victoria, P.O. Box 3055 STN CSC,Victoria BC, Canada, V8P 5C2 0 #12;Abstract A reformulation of the simple model
A three-dimensional surface waveocean circulation coupled model and its initial testing
Ezer,Tal
models is established based on Reynolds stresses and fluxes terms derived from surface wave to 0.93 with wave influence. The wave-induced Reynolds stress can reach up to about 5% of the wind stress in high latitudes, and drive 23 Sv transport in the global ocean in the form of mesoscale eddies
Paris-Sud XI, Université de
) is a basic model for the study of shape- changing underwater vehicles made of rigid parts linked together, stealthier and more maneuverable than if propeller-driven. So-called autonomous underwater vehicles (AUV) or unmanned undersea vehicles (UUV) have been used extensively to carry out varied missions: for instance
The Transition-Zone Water Filter Model for Global Material Circulation: Where Do We Stand?
with a small melt fraction, highly incompatible elements including hydro- gen, helium and argon are sequestered the fraction of water is small. Models have been developed to understand the structure of a melt layer Hilst, et al., 1997]), then the whole mantle is depleted with only a small volume (~10%) of relatively
Generalization of neuron network model with delay feedback
Sanjeet Maisnam; R. K. Brojen Singh
2015-07-16T23:59:59.000Z
We present generalized delayed neural network (DNN) model with positive delay feedback and neuron history. The local stability analysis around trivial local equilibria of delayed neural networks has applied and determine the conditions for the existence of zero root. We develop few innovative delayed neural network models in different dimensions through transformation and extension of some existing models. We found that zero root can have multiplicity two under certain conditions. We further show how the characteristic equation can have zero root and its multiplicity is dependent on the conditions undertaken. Finally, we generalize the neural network of $N$ neurons through which we determine the general form of Jacobian of the linear form and corresponding characteristic equation of the system.
Virasoro representations and fusion for general augmented minimal models
Holger Eberle; Michael Flohr
2006-04-13T23:59:59.000Z
In this paper we present explicit results for the fusion of irreducible and higher rank representations in two logarithmically conformal models, the augmented c_{2,3} = 0 model as well as the augmented Yang-Lee model at c_{2,5} = -22/5. We analyse their spectrum of representations which is consistent with the symmetry and associativity of the fusion algebra. We also describe the first few higher rank representations in detail. In particular, we present the first examples of consistent rank 3 indecomposable representations and describe their embedding structure. Knowing these two generic models we also conjecture the general representation content and fusion rules for general augmented c_{p,q} models.
General Treatment of All 2d Covariant Models
W. Kummer
1996-12-06T23:59:59.000Z
General matterless models of gravity include dilaton gravity, arbitrary powers in curvature, but also dynamical torsion. They are a special class of "Poisson-sigma-models" whose solutions are known completely, together with their general global structure. Beside the ordinary black hole, arbitrary singularity structures can be studied. It is also possible to derive an action "backwards", starting from a given manifold. The role of conservation laws, Noether charge and the quantization have been investigated. Scalar and fermionic matter fields may be included as well.
A preliminary model of the circulating blood for use in radiation dose calculations
Hui, Tsz-Yik Edmond
1986-01-01T23:59:59.000Z
of Advisory Committee: Dr. John W. Poston Currently, there is a need for a dosimetric model to describe the circulatory system in an adult human. This need exists because of the increasing number of radiopharmaceuticals used in nuclear medicine which... Administered Activity for Indium-113m-labeled Blood Platelets for Selected Organs biological data on blood volume and distribution in the circulatory system (A163, Ba61, Co71, Fo71, Sm84, Mc74) . Only major organs that contain large amounts of blood were...
Modeling Smart Grid using Generalized Stochastic Petri Net
Dey, Amrita; Sanyal, Sugata
2011-01-01T23:59:59.000Z
Building smart grid for power system is a major challenge for safe, automated and energy efficient usage of electricity. The full implementation of the smart grid will evolve over time. However, before a new set of infrastructures are invested to build the smart grid, proper modeling and analysis is needed to avoid wastage of resources. Modeling also helps to identify and prioritize appropriate systems parameters. In this paper, an all comprehensive model of smart grid have been proposed using Generalized Stochastic Petri Nets (GSPN). The model is used to analyze the constraints and deliverables of the smart power grid of future.
Interacting holographic dark energy models: A general approach
S. Som; A. Sil
2014-12-01T23:59:59.000Z
Dark energy models inspired by the cosmological holographic principle are studied in homogeneous isotropic spacetime with a general choice for the dark energy density $\\rho_d=3(\\alpha H^2+\\beta\\dot{H})$. Special choices of the parameters enable us to obtain three different holographic models, including the holographic Ricci dark energy(RDE) model. Effect of interaction between dark matter and dark energy on the dynamics of those models are investigated for different popular forms of interaction. It is found that crossing of phantom divide can be avoided in RDE models for $\\beta>0.5$ irrespective of the presence of interaction. A choice of $\\alpha=1$ and $\\beta=2/3$ leads to a varying $\\Lambda$-like model introducing an IR cutoff length $\\Lambda^{-1/2}$. It is concluded that among the popular choices an interaction of the form $Q\\propto H\\rho_m$ suits the best in avoiding the coincidence problem in this model.
New agegraphic dark energy model with generalized uncertainty principle
Yong-Wan Kim; Hyung Won Lee; Yun Soo Myung; Mu-In Park
2008-08-07T23:59:59.000Z
We investigate the new agegraphic dark energy models with generalized uncertainty principle (GUP). It turns out that although the GUP affects the early universe, it does not change the current and future dark energy-dominated universe significantly. Furthermore, this model could describe the matter-dominated universe in the past only when the parameter $n$ is chosen to be $n>n_c$, where the critical value determined to be $n_c=2.799531478$.
General Network Lifetime and Cost Models for Evaluating Sensor Network
Heinzelman, Wendi
General Network Lifetime and Cost Models for Evaluating Sensor Network Deployment Strategies Zhao Cheng, Mark Perillo, and Wendi B. Heinzelman, Senior Member, IEEE Abstract--In multihop wireless sensor to energy imbalance among sensors often appear. Sensors closer to a data sink are usually required
Abstract polymer models with general pair interactions Aldo Procacci
Procacci, Aldo
Abstract polymer models with general pair interactions Aldo Procacci Dep. MatemÂ´atica-ICEx, UFMG (i.e. not necessarily hard core or repulsive). A concrete example is given in which polymers are r0 (possibly attractive), of the type 1/rd+ with > 0. 1. Introduction The abstract polymer gas is an important
GENERALIZED LINEAR MODELING APPROACH TO STOCHASTIC WEATHER GENERATORS
Katz, Richard
) Multisites (Spatial dependence of daily weather) -- Software R open source statistical programming language (Capable of "reproducing" any desired statistic) -- Disadvantages Synthetic weather looks too much like") Not amenable to uncertainty analysis #12;#12;#12;(2) Generalized Linear Models · Statistical Framework
Pseudo supersymmetric partners for the generalized Swanson model
A. Sinha; P. Roy
2008-06-27T23:59:59.000Z
New non Hermitian Hamiltonians are generated, as isospectral partners of the generalized Swanson model, viz., $ H_- = {\\cal{A}}^{\\dagger} {\\cal{A}} + \\alpha {\\cal{A}} ^2 + \\beta {\\cal{A}}^{\\dagger 2} $, where $ \\alpha \\beta $ are real constants, with $ \\alpha \
GENERALIZED STIRLING PERMUTATIONS, FAMILIES OF INCREASING TREES AND URN MODELS
Janson, Svante
GENERALIZED STIRLING PERMUTATIONS, FAMILIES OF INCREASING TREES AND URN MODELS SVANTE JANSON and descents in the class of Stirling permutations, introduced by Gessel and Stanley [14]. Recently, Janson [18] showed the connection between Stirling permutations and plane recursive trees and proved a joint nor- mal
Holographic entanglement entropy in general holographic superconductor models
Yan Peng; Qiyuan Pan
2014-04-07T23:59:59.000Z
We study the entanglement entropy of general holographic dual models both in AdS soliton and AdS black hole backgrounds with full backreaction. We find that the entanglement entropy is a good probe to explore the properties of the holographic superconductors and provides richer physics in the phase transition. We obtain the effects of the scalar mass, model parameter and backreaction on the entropy, and argue that the jump of the entanglement entropy may be a quite general feature for the first order phase transition. In strong contrast to the insulator/superconductor system, we note that the backreaction coupled with the scalar mass can not be used to trigger the first order phase transition if the model parameter is below its bottom bound in the metal/superconductor system.
A general holographic metal/superconductor phase transition model
Yan Peng; Yunqi Liu
2014-10-27T23:59:59.000Z
We study the scalar condensation of a general holographic superconductor model in AdS black hole background away from the probe limit. We find the model parameters together with the scalar mass and backreaction can determine the order of phase transitions completely. In addition, we observe two types of discontinuities of the scalar operator in the case of first order phase transitions. We analyze in detail the effects of the scalar mass and backreaction on the formation of discontinuities and arrive at an approximate relation between the threshold model parameters. Furthermore, we obtain superconductor solutions corresponding to higher energy states and examine the stability of these superconductor solutions.
A general holographic metal/superconductor phase transition model
Yan Peng; Yunqi Liu
2015-03-03T23:59:59.000Z
We study the scalar condensation of a general holographic superconductor model in AdS black hole background away from the probe limit. We find the model parameters together with the scalar mass and backreaction can determine the order of phase transitions completely. In addition, we observe two types of discontinuities of the scalar operator in the case of first order phase transitions. We analyze in detail the effects of the scalar mass and backreaction on the formation of discontinuities and arrive at an approximate relation between the threshold model parameters. Furthermore, we obtain superconductor solutions corresponding to higher energy states and examine the stability of these superconductor solutions.
Bleck, R.
2004-05-19T23:59:59.000Z
The overall aim of this project was to continue development of a global version of the Miami Isopycnic Coordinate Ocean Model (MICOM) with the intent of turning it into a full-fledged oceanic component of an earth system model.
Spontaneous symmetry breaking in a generalized orbital compass model
Lukasz Cincio; Jacek Dziarmaga; Andrzej M. Oles
2010-09-10T23:59:59.000Z
We introduce a generalized two-dimensional orbital compass model, which interpolates continuously from the classical Ising model to the orbital compass model with frustrated quantum interactions, and investigate it using the multiscale entanglement renormalization ansatz (MERA). The results demonstrate that increasing frustration of exchange interactions triggers a second order quantum phase transition to a degenerate symmetry broken state which minimizes one of the interactions in the orbital compass model. Using boson expansion within the spin-wave theory we unravel the physical mechanism of the symmetry breaking transition as promoted by weak quantum fluctuations and explain why this transition occurs only surprisingly close to the maximally frustrated interactions of the orbital compass model. The spin waves remain gapful at the critical point, and both the boson expansion and MERA do not find any algebraically decaying spin-spin correlations in the critical ground state.
B Decays in a General Left-Right Symmetric Model
Frank, Mariana; Turan, Ismail
2010-01-01T23:59:59.000Z
Motivated by recently observed disagreements with the SM predictions in B decays, we study $b \\to d, s$ transitions in a general class of $SU(2)_L \\times SU(2)_R \\times U(1)_{B-L}$ models, with a simple one-parameter structure of the right handed mixing matrix for the quarks, which obeys the constraints from kaon physics. We use experimental constraints on the branching ratios of $b \\to s \\gamma$, $b \\to c e {\\bar \
Exceptional and regular spectra of a generalized Rabi model
Michael Tomka; Omar El Araby; Mikhail Pletyukhov; Vladimir Gritsev
2014-12-05T23:59:59.000Z
We study the spectrum of the generalized Rabi model in which co- and counter-rotating terms have different coupling strengths. It is also equivalent to the model of a two-dimensional electron gas in a magnetic field with Rashba and Dresselhaus spin-orbit couplings. Like in case of the Rabi model, the spectrum of the generalized Rabi model consists of the regular and the exceptional parts. The latter is represented by the energy levels which cross at certain parameters' values which we determine explicitly. The wave functions of these exceptional states are given by finite order polynomials in the Bargmann representation. The roots of these polynomials satisfy a Bethe ansatz equation of the Gaudin type. At the exceptional points the model is therefore quasi-exactly solvable. An analytical approximation is derived for the regular part of the spectrum in the weak- and strong-coupling limits. In particular, in the strong-coupling limit the spectrum consists of two quasi-degenerate equidistant ladders.
A dark energy model alternative to generalized Chaplygin gas
Hoavo Hova; Huanxiong Yang
2010-11-22T23:59:59.000Z
We propose a new fluid model of dark energy for $-1 \\leq \\omega_{\\text{eff}} \\leq 0$ as an alternative to the generalized Chaplygin gas models. The energy density of dark energy fluid is severely suppressed during barotropic matter dominant epochs, and it dominates the universe evolution only for eras of small redshift. From the perspective of fundamental physics, the fluid is a tachyon field with a scalar potential flatter than that of power-law decelerated expansion. Different from the standard $\\Lambda\\text{CDM}$ model, the suggested dark energy model claims that the cosmic acceleration at present epoch can not continue forever but will cease in the near future and a decelerated cosmic expansion will recover afterwards.
A dark energy model alternative to generalized Chaplygin gas
Hova, Hoavo
2010-01-01T23:59:59.000Z
We propose a new fluid model of dark energy for $-1 \\leq \\omega_{\\text{eff}} \\leq 0$ as an alternative to the generalized Chaplygin gas models. The energy density of dark energy fluid is severely suppressed during barotropic matter dominant epochs, and it dominates the universe evolution only for eras of small redshift. From the perspective of fundamental physics, the fluid is a tachyon field with a scalar potential flatter than that of power-law decelerated expansion. Different from the standard $\\Lambda\\text{CDM}$ model, the suggested dark energy model claims that the cosmic acceleration at present epoch can not continue forever but will cease in the near future and a decelerated cosmic expansion will recover afterwards.
Simple ocean carbon cycle models
Caldeira, K. [Lawrence Livermore National Lab., CA (United States); Hoffert, M.I. [New York Univ., NY (United States). Dept. of Earth System Sciences; Siegenthaler, U. [Bern Univ. (Switzerland). Inst. fuer Physik
1994-02-01T23:59:59.000Z
Simple ocean carbon cycle models can be used to calculate the rate at which the oceans are likely to absorb CO{sub 2} from the atmosphere. For problems involving steady-state ocean circulation, well calibrated ocean models produce results that are very similar to results obtained using general circulation models. Hence, simple ocean carbon cycle models may be appropriate for use in studies in which the time or expense of running large scale general circulation models would be prohibitive. Simple ocean models have the advantage of being based on a small number of explicit assumptions. The simplicity of these ocean models facilitates the understanding of model results.
$so(N)_1$ criticality in generalized cluster models
Ville Lahtinen; Eddy Ardonne
2015-04-27T23:59:59.000Z
We show that $so(N)_1$ universality class quantum criticality emerges when one-dimensional generalized cluster models -- the N-cluster models -- are perturbed with Ising or Zeeman terms. Each critical point is described by a low-energy theory of N linearly dispersing fermions, whose spectrum we show to precisely match the prediction by $so(N)_1$ conformal field theory. Furthermore, by an explicit construction we show that the N-cluster models are dual to N non-locally coupled transverse field Ising chains, which enables to identify local representations for the primary fields and shows that the N-cluster models provide the simplest representation of the recently introduced hierarchy of $so(N)_1$ critical spin models. For the experimentally most realistic case of N=3, that corresponds to the original one-dimensional cluster model, our results show that $su(2)_2 \\simeq so(3)_1$ Wess-Zumino-Witten model can emerge in a local, translationally invariant and Jordan-Wigner solvable spin-1/2 model.
Long-term effects of anthropogenic CO2 emissions simulated with a complex earth system model
Winguth, Arne
Long-term effects of anthropogenic CO2 emissions simulated with a complex earth system model Uwe earth system model con- sisting of an atmospheric general circulation model, an ocean general
Reshocks, rarefactions, and the generalized Layzer model for hydrodynamic instabilities
Mikaelian, K O
2008-06-10T23:59:59.000Z
We report numerical simulations and analytic modeling of shock tube experiments on Rayleigh-Taylor and Richtmyer-Meshkov instabilities. We examine single interfaces of the type A/B where the incident shock is initiated in A and the transmitted shock proceeds into B. Examples are He/air and air/He. In addition, we study finite-thickness or double-interface A/B/A configurations like air/SF{sub 6}/air gas-curtain experiments. We first consider conventional shock tubes that have a 'fixed' boundary: A solid endwall which reflects the transmitted shock and reshocks the interface(s). Then we focus on new experiments with a 'free' boundary--a membrane disrupted mechanically or by the transmitted shock, sending back a rarefaction towards the interface(s). Complex acceleration histories are achieved, relevant for Inertial Confinement Fusion implosions. We compare our simulation results with a generalized Layzer model for two fluids with time-dependent densities, and derive a new freeze-out condition whereby accelerating and compressive forces cancel each other out. Except for the recently reported failures of the Layzer model, the generalized Layzer model and hydrocode simulations for reshocks and rarefactions agree well with each other, and remain to be verified experimentally.
Perturbations in Bouncing and Cyclic Models, a General Study
Biswas, Tirthabir; Lattyak, Colleen
2015-01-01T23:59:59.000Z
Being able to reliably track perturbations across bounces and turnarounds in cyclic and bouncing cosmology lies at the heart of being able to compare the predictions of these models with the Cosmic Microwave Background observations. This has been a challenging task due to the unknown nature of the physics involved during the bounce as well as the technical challenge of matching perturbations precisely between the expansion and contraction phases. In this paper, we will present general techniques (analytical and numerical) that can be applied to understand the physics of the fluctuations, especially those with "long" wavelengths, and test its validity in some simple bouncing/cyclic toy models where the physics is well understood. We will then apply our techniques to more interesting cosmological models such as the bounce inflation and cyclic inflation.
Perturbations in Bouncing and Cyclic Models, a General Study
Tirthabir Biswas; Riley Mayes; Colleen Lattyak
2015-02-18T23:59:59.000Z
Being able to reliably track perturbations across bounces and turnarounds in cyclic and bouncing cosmology lies at the heart of being able to compare the predictions of these models with the Cosmic Microwave Background observations. This has been a challenging task due to the unknown nature of the physics involved during the bounce as well as the technical challenge of matching perturbations precisely between the expansion and contraction phases. In this paper, we will present general techniques (analytical and numerical) that can be applied to understand the physics of the fluctuations, especially those with "long" wavelengths, and test its validity in some simple bouncing/cyclic toy models where the physics is well understood. We will then apply our techniques to more interesting cosmological models such as the bounce inflation and cyclic inflation.
Generalized lepton number and dark left-right gauge model
Khalil, Shaaban [Center for Theoretical Physics, British University in Egypt, El Sherouk City, Postal No. 11837, P.O. Box 43 (Egypt); Department of Mathematics, Ain Shams University, Faculty of Science, Cairo 11566 (Egypt); Lee, Hye-Sung; Ma, Ernest [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States)
2009-02-15T23:59:59.000Z
In a left-right gauge model of particle interactions, the left-handed fermion doublet ({nu},e){sub L} is connected to its right-handed counterpart (n,e){sub R} through a scalar bidoublet so that e{sub L} pairs with e{sub R}, and {nu}{sub L} with n{sub R} to form mass terms. Suppose the latter link is severed without affecting the former, then n{sub R} is not the mass partner of {nu}{sub L}, and as we show in this paper, becomes a candidate for dark matter which is relevant for the recent PAMELA and ATIC observations. We accomplish this in a specific nonsupersymmetric model, where a generalized lepton number can be defined, so that n{sub R} and W{sub R}{sup {+-}} are odd under R{identical_to}(-1){sup 3B+L+2j}. Fermionic leptoquarks are also predicted.
Dynamics of the Thermohaline Circulation under Wind forcing
Hongjun Gao; Jinqiao Duan
2001-08-12T23:59:59.000Z
The ocean thermohaline circulation, also called meridional overturning circulation, is caused by water density contrasts. This circulation has large capacity of carrying heat around the globe and it thus affects the energy budget and further affects the climate. We consider a thermohaline circulation model in the meridional plane under external wind forcing. We show that, when there is no wind forcing, the stream function and the density fluctuation (under appropriate metrics) tend to zero exponentially fast as time goes to infinity. With rapidly oscillating wind forcing, we obtain an averaging principle for the thermohaline circulation model. This averaging principle provides convergence results and comparison estimates between the original thermohaline circulation and the averaged thermohaline circulation, where the wind forcing is replaced by its time average. This establishes the validity for using the averaged thermohaline circulation model for numerical simulations at long time scales.
2009-01-01T23:59:59.000Z
2009 P. E. Thornton et al. : Carbon-nitrogen interactionsregulate climate-carbon cycle feedbacks Monfray, P. ,T. H. : A global ocean carbon climatology: Results from
Generalized Modeling of Enrichment Cascades That Include Minor Isotopes
Weber, Charles F [ORNL
2012-01-01T23:59:59.000Z
The monitoring of enrichment operations may require innovative analysis to allow for imperfect or missing data. The presence of minor isotopes may help or hurt - they can complicate a calculation or provide additional data to corroborate a calculation. However, they must be considered in a rigorous analysis, especially in cases involving reuse. This study considers matched-abundanceratio cascades that involve at least three isotopes and allows generalized input that does not require all feed assays or the enrichment factor to be specified. Calculations are based on the equations developed for the MSTAR code but are generalized to allow input of various combinations of assays, flows, and other cascade properties. Traditional cascade models have required specification of the enrichment factor, all feed assays, and the product and waste assays of the primary enriched component. The calculation would then produce the numbers of stages in the enriching and stripping sections and the remaining assays in waste and product streams. In cases where the enrichment factor or feed assays were not known, analysis was difficult or impossible. However, if other quantities are known (e.g., additional assays in waste or product streams), a reliable calculation is still possible with the new code, but such nonstandard input may introduce additional numerical difficulties into the calculation. Thus, the minimum input requirements for a stable solution are discussed, and a sample problem with a non-unique solution is described. Both heuristic and mathematically required guidelines are given to assist the application of cascade modeling to situations involving such non-standard input. As a result, this work provides both a calculational tool and specific guidance for evaluation of enrichment cascades in which traditional input data are either flawed or unknown. It is useful for cases involving minor isotopes, especially if the minor isotope assays are desired (or required) to be important contributors to the overall analysis.
Proton radioactivity within a generalized liquid drop model
J. M. Dong; H. F. Zhang; G. Royer
2009-06-02T23:59:59.000Z
The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of protons are determined in the quasimolecular shape path within a generalized liquid drop model (GLDM) including the proximity effects between nuclei in a neck and the mass and charge asymmetry. The penetrability is calculated with the WKB approximation. The spectroscopic factor has been taken into account in half-life calculation, which is obtained by employing the relativistic mean field (RMF) theory combined with the BCS method with the force NL3. The half-lives within the GLDM are compared with the experimental data and other theoretical values. The GLDM works quite well for spherical proton emitters when the spectroscopic factors are considered, indicating the necessity of introducing the spectroscopic factor and the success of the GLDM for proton emission. Finally, we present two formulas for proton emission half-life calculation similar to the Viola-Seaborg formulas and Royer's formulas of alpha decay.
Control of a Circulating Fluidized Bed
Shim, Hoowang; Rickards, Gretchen; Famouri, Parviz; Turton, Richard (WVU); Sams, W. Neal (EG& G); Koduro, Praveen; Patankar, Amol; Davari, Assad (WVUIT); Lawson, Larry; Boyle, Edward J. (DOE)
2001-11-06T23:59:59.000Z
Two methods for optimally controlling the operation of a circulating fluidized bed are being investigated, neural network control and Kalman filter control. The neural network controls the solids circulation rate by adjusting the flow of move air in the non-mechanical valve. Presented is the method of training the neural network from data generated by the circulating fluidized bed (CFB), the results of a sensitivity study indicating that adjusting the move air can control solids flow, and the results of controlling solids circulation rate. The Kalman filter approach uses a dynamic model and a measurement model of the standpipe section of the CFB. Presented are results showing that a Kalman filter can successfully find the standpipe bed height.
Water isotopes and the general circulation
Noone, David
is depleted. #12;Distillation: vapor and condensate Isotopic fractionation -35 -30 -25 -20 -15 -10 -5 0 5 0 0 of idealized isotopic fractionation Expression of isotopic fractionation in nature Attributing signals" 18 = (R/Rstandard-1)x1000 R = moles of H2 18O/moles of H2 16O #12;Isotopic fractionation Isotopic
A Generalized Notion of Platforms for Model Driven Development
KÃ¼hne, Thomas
, 64289 Darmstadt, Germany kuehne@informatik.tu-darmstadt.de 1 Introduction Model driven development (MDD
Generalized charge-screening in relativistic Thomas–Fermi model
Akbari-Moghanjoughi, M. [Department of Physics, Faculty of Sciences, Azarbaijan Shahid Madani University, 51745-406 Tabriz, Iran and International Centre for Advanced Studies in Physical Sciences and Institute for Theoretical Physics, Ruhr University Bochum, D-44780 Bochum (Germany)
2014-10-15T23:59:59.000Z
In this paper, we study the charge shielding within the relativistic Thomas-Fermi model for a wide range of electron number-densities and the atomic-number of screened ions. A generalized energy-density relation is obtained using the force-balance equation and taking into account the Chandrasekhar's relativistic electron degeneracy pressure. By numerically solving a second-order nonlinear differential equation, the Thomas-Fermi screening length is investigated, and the results are compared for three distinct regimes of the solid-density, warm-dense-matter, and white-dwarfs (WDs). It is revealed that our nonlinear screening theory is compatible with the exponentially decaying Thomas-Fermi-type shielding predicted by the linear response theory. Moreover, the variation of relative Thomas-Fermi screening length shows that extremely dense quantum electron fluids are relatively poor charge shielders. Calculation of the total number of screening electrons around a nucleus shows that there is a position of maximum number of screening localized electrons around the screened nucleus, which moves closer to the point-like nucleus by increase in the plasma number density but is unaffected due to increase in the atomic-number value. It is discovered that the total number of screening electrons, (N{sub s}?r{sub TF}{sup 3}/r{sub d}{sup 3} where r{sub TF} and r{sub d} are the Thomas-Fermi and interparticle distance, respectively) has a distinct limit for extremely dense plasmas such as WD-cores and neutron star crusts, which is unique for all given values of the atomic-number. This is equal to saying that in an ultrarelativistic degeneracy limit of electron-ion plasma, the screening length couples with the system dimensionality and the plasma becomes spherically self-similar. Current analysis can provide useful information on the effects of relativistic correction to the charge screening for a wide range of plasma density, such as the inertial-confined plasmas and compact stellar objects.
Circulating Fluid Bed Combustor
Fraley, L. D.; Do, L. N.; Hsiao, K. H.
1982-01-01T23:59:59.000Z
The circulating bed combustor represents an alternative concept of burning coal in fluid bed technology, which offers distinct advantages over both the current conventional fluidized bed combustion system and the pulverized coal boilers equipped...
Global circulation as the main source of cloud activity on Titan
Rodriguez, Sébastien; Rannou, Pascal; Tobie, Gabriel; Baines, Kevin H; Barnes, Jason W; Griffith, Caitlin A; Hirtzig, Mathieu; Pitman, Karly M; Sotin, Christophe; Brown, Robert H; Buratti, Bonnie J; Clark, Roger N; Nicholson, Phil D; 10.1038/NATURE08014
2009-01-01T23:59:59.000Z
Clouds on Titan result from the condensation of methane and ethane and, as on other planets, are primarily structured by circulation of the atmosphere. At present, cloud activity mainly occurs in the southern (summer) hemisphere, arising near the pole and at mid-latitudes from cumulus updrafts triggered by surface heating and/or local methane sources, and at the north (winter) pole, resulting from the subsidence and condensation of ethane-rich air into the colder troposphere. General circulation models predict that this distribution should change with the seasons on a 15-year timescale, and that clouds should develop under certain circumstances at temperate latitudes (~40\\degree) in the winter hemisphere. The models, however, have hitherto been poorly constrained and their long-term predictions have not yet been observationally verified. Here we report that the global spatial cloud coverage on Titan is in general agreement with the models, confirming that cloud activity is mainly controlled by the global circ...
Introduction to (Generalized) Autoregressive Conditional Heteroskedasticity Models in Time Series
Morrow, James A.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4 ARCH/GARCH models 8 4.1 Sample Application and application of the ARCH/GARCH models proposed in the 1980's by econometricians such as Robert Engle (who won at the time). In particular, we focus on the paper, "GARCH 101: The Use of ARCH/GARCH Models in Applied Econo
General coarse-grained red blood cell models: I. Mechanics
Fedosov, Dmitry A; Karniadakis, George E
2009-01-01T23:59:59.000Z
We present a rigorous procedure to derive coarse-grained red blood cell (RBC) models, which lead to accurate mechanical properties of realistic RBCs. Based on a semi-analytic theory linear and non-linear elastic properties of the RBC membrane can be matched with those obtained in optical tweezers stretching experiments. In addition, we develop a nearly stress-free model which avoids a number of pitfalls of existing RBC models, such as non-biconcave equilibrium shape and dependence of RBC mechanical properties on the triangulation quality. The proposed RBC model is suitable for use in many existing numerical methods, such as Lattice Boltzmann, Multiparticle Collision Dynamics, Immersed Boundary, etc.
General coarse-grained red blood cell models: I. Mechanics
Dmitry A. Fedosov; Bruce Caswell; George E. Karniadakis
2009-05-01T23:59:59.000Z
We present a rigorous procedure to derive coarse-grained red blood cell (RBC) models, which lead to accurate mechanical properties of realistic RBCs. Based on a semi-analytic theory linear and non-linear elastic properties of the RBC membrane can be matched with those obtained in optical tweezers stretching experiments. In addition, we develop a nearly stress-free model which avoids a number of pitfalls of existing RBC models, such as non-biconcave equilibrium shape and dependence of RBC mechanical properties on the triangulation quality. The proposed RBC model is suitable for use in many existing numerical methods, such as Lattice Boltzmann, Multiparticle Collision Dynamics, Immersed Boundary, etc.
Generalized Electric Polarizability of the Proton from Skyrme Model
Myunggyu Kim; Dong-Pil Min
1997-04-23T23:59:59.000Z
We calculate the electric polarizability $\\alpha(q^2)$ of the proton in virtual Compton scattering using the Skyrme model. The $q^2$ dependence of the polarizability is comparable with the predictions obtained from the non-relativistic quark model and the linear sigma model. The chiral behaviors of our $\\alpha(0)$ and $d^2\\alpha(0)/d^2q^2$ agree with the results of the chiral perturbation theory. The discrepancy can be traced back to the contribution of the intermediate $\\Delta$ state degenerate with the $N$ which is a characteristic of a large-$N_C$ model.
A GENERALIZED SURVEILLANCE MODEL WITH APPLICATIONS TO SYSTEMS SAFETY
Xie, Minge
performing satisfactorily. For example, the Federal Aviation Administration (FAA) [3] is the regulatory a development of this model is an FAA project, where we were asked to develop a surveillance model to better agency for aviation safety in the Unites States. Their aviation safety inspectors need to quickly
General Methodology for developing UML models from UI
Reddy, Ch Ram Mohan; Srinivasa, K G; Kumar, T V Suresh; Kanth, K Rajani
2012-01-01T23:59:59.000Z
In recent past every discipline and every industry have their own methods of developing products. It may be software development, mechanics, construction, psychology and so on. These demarcations work fine as long as the requirements are within one discipline. However, if the project extends over several disciplines, interfaces have to be created and coordinated between the methods of these disciplines. Performance is an important quality aspect of Web Services because of their distributed nature. Predicting the performance of web services during early stages of software development is significant. In Industry, Prototype of these applications is developed during analysis phase of Software Development Life Cycle (SDLC). However, Performance models are generated from UML models. Methodologies for predicting the performance from UML models is available. Hence, In this paper, a methodology for developing Use Case model and Activity model from User Interface is presented. The methodology is illustrated with a case...
A generalized logistic model of individual tree mortality for aspen, white spruce, and lodgepole
Macdonald, Ellen
A generalized logistic model of individual tree mortality for aspen, white spruce, and lodgepole: A generalized logistic model of individual tree mortality was developed for trembling aspen (Populus tremuloides aspen (Populus tremuloides Michx), white spruce (Picea glauca (Moench) Voss), and lodgepole pine (Pinus
From residue matching patterns to protein folding topographies: General model and bovine
Berry, R. Stephen
From residue matching patterns to protein folding topographies: General model and bovine pancreatic-grained model for protein-folding dynamics is introduced based on a discretized representation of torsional, pattern recognition, and general characteristics of protein folding kinetics. Topology here implies
STATISTICAL MODELS FOR MULTIPLE SEQUENCE ALIGNMENT: UNIFICATIONS AND GENERALIZATIONS
Liu, Jun
, Stanford University; Charles E. Lawrence, NYSDOH Jun S. Liu, Department of Statistics, Stanford University and our main point of interest. We believe that building explicit statistical model is an important
Dark Energy - Dark Matter Unification: Generalized Chaplygin Gas Model
Orfeu Bertolami
2005-04-14T23:59:59.000Z
We review the main features of the generalized Chaplygin gas (GCG) proposal for unification of dark energy and dark matter and discuss how it admits an unique decomposition into dark energy and dark matter components once phantom-like dark energy is excluded. In the context of this approach we consider structure formation and show that unphysical oscillations or blow-up in the matter power spectrum are not present. Moreover, we demonstrate that the dominance of dark energy occurs about the time when energy density fluctuations start evolving away from the linear regime.
General Equilibrium Modeling Package (GEMPACK) | Open Energy Information
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 You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489InformationFrenchtown,Jump to: navigation, search Name:General
Subin, Z.M.
2013-01-01T23:59:59.000Z
remote ocean temperatures to respond, whereas a terrestrial cooling,summer cooling at 850 hPa. Significant remote changescooling due to a change in ocean circulation would imply a compensating remote
The Transient Circulation Response to Radiative Forcings and Sea Surface Warming
Staten, Paul; Reichler, Thomas; Lu, Jian
2014-12-15T23:59:59.000Z
Tropospheric circulation shifts have strong potential to impact surface climate. But the magnitude of these shifts in a changing climate, and the attending regional hydrological changes, are difficult to project. Part of this difficulty arises from our lack of understanding of the physical mechanisms behind the circulation shifts themselves. In order to better delineate circulation shifts and their respective causes, we decompose the circulation response into (1) the "direct" response to radiative forcings themselves, and (2) the "indirect" response to changing sea surface temperatures. Using ensembles of 90-day climate model simulations with immediate switch-on forcings, including perturbed greenhouse gas concentrations, stratospheric ozone concentrations, and sea surface temperatures, we document the direct and indirect transient responses of the zonal mean general circulation, and investigate the roles of previously proposed mechanisms in shifting the midlatitude jet. We find that both the direct and indirect wind responses often begin in the lower stratosphere. Changes in midlatitude eddies are ubiquitous and synchronous with the midlatitude zonal wind response. Shifts in the critical latitude of wave absorption on either flank of the jet are not indicted as primary factors for the poleward shifting jet, although we see some evidence for increasing equatorward wave reflection over the southern hemisphere in response to sea surface warming. Mechanisms for the northern hemisphere jet shift are less clear.
Baryonic torii: Toroidal baryons in a generalized Skyrme model
Sven Bjarke Gudnason; Muneto Nitta
2015-02-10T23:59:59.000Z
We study a Skyrme-type model with a potential term motivated by Bose-Einstein condensates (BECs), which we call the BEC Skyrme model. We consider two flavors of the model, the first is the Skyrme model and the second has a sixth-order derivative term instead of the Skyrme term; both with the added BEC-motivated potential. The model contains toroidally shaped Skyrmions and they are characterized by two integers P and Q, representing the winding numbers of two complex scalar fields along the toroidal and poloidal cycles of the torus, respectively. The baryon number is B=PQ. We find stable Skyrmion solutions for P=1,2,3,4,5 with Q=1, while for P=6 and Q=1 it is only metastable. We further find that configurations with higher Q>1 are all unstable and split into Q configurations with Q=1. Finally we discover a phase transition, possibly of first order, in the mass parameter of the potential under study.
Generalized Ginzburg-Landau models for non-conventional superconductors
S. Esposito; G. Salesi
2009-06-20T23:59:59.000Z
We review some recent extensions of the Ginzburg-Landau model able to describe several properties of non-conventional superconductors. In the first extension, s-wave superconductors endowed with two different critical temperatures are considered, their main thermodynamical and magnetic properties being calculated and discussed. Instead in the second extension we describe spin-triplet superconductivity (with a single critical temperature), studying in detail the main predicted physical properties. A thorough discussion of the peculiar predictions of our models and their physical consequences is as well performed.
van Hulten, Marco; Middag, Rob; de Baar, Hein; Gehlen, Marion; Dutay, Jean-Claude; Tagliabue, Alessandro
2014-01-01T23:59:59.000Z
The distribution of dissolved aluminium in the West Atlantic Ocean shows a mirror image with that of dissolved silicic acid, hinting at intricate interactions between the ocean cycling of Al and Si. The marine biogeochemistry of Al is of interest because of its potential impact on diatom opal remineralisation, hence Si availability. Furthermore, the dissolved Al concentration at the surface ocean has been used as a tracer for dust input, dust being the most important source of the bio-essential trace element iron to the ocean. Previously, the dissolved concentration of Al was simulated reasonably well with only a dust source, and scavenging by adsorption on settling biogenic debris as the only removal process. Here we explore the impacts of (i) a sediment source of Al in the Northern Hemisphere (especially north of ~40{\\deg}N), (ii) the imposed velocity field, and (iii) biological incorporation of Al on the modelled Al distribution in the ocean. The sediment source clearly improves the model results, and usin...
Modelling general relativistic perfect fluids in field theoretic language
Nikolai V. Mitskievich
1998-11-23T23:59:59.000Z
Skew-symmetric massless fields, their potentials being $r$-forms, are close analogues of Maxwell's field (though the non-linear cases also should be considered). We observe that only two of them ($r=$2 and 3) automatically yield stress-energy tensors characteristic to normal perfect fluids. It is shown that they naturally describe both non-rotating ($r=2$) and rotating (then a combination of $r=2$ and $r=3$ fields is indispensable) general relativistic perfect fluids possessing every type of equations of state. Meanwile, a free $r=3$ field is completely equivalent to appearance of the cosmological term in Einstein's equations. Sound waves represent perturbations propagating on the background of the $r=2$ field. Some exotic properties of these two fields are outlined.
Lost circulation in geothermal wells: survey and evaluation of industry experience
Goodman, M.A.
1981-07-01T23:59:59.000Z
Lost circulation during drilling and completion of geothermal wells can be a severe problem, particularly in naturally fractured and/or vugular formations. Geothermal and petroleum operators, drilling service companies, and independent consultants were interviewed to assess the lost circulation problem in geothermal wells and to determine general practices for preventing lost circulation. This report documents the results and conclusions from the interviews and presents recommendations for needed research. In addition, a survey was also made of the lost circulation literature, of currently available lost circulation materials, and of existing lost circulation test equipment.
Karl Svozil
2001-06-29T23:59:59.000Z
Three extensions and reinterpretations of nonclassical probabilities are reviewed. (i) We propose to generalize the probability axiom of quantum mechanics to self-adjoint positive operators of trace one. Furthermore, we discuss the Cartesian and polar decomposition of arbitrary normal operators and the possibility to operationalize the corresponding observables. Thereby we review and emphasize the use of observables which maximally represent the context. (ii) In the second part, we discuss Pitowsky polytopes for automaton logic as well as for generalized urn models and evaluate methods to find the resulting Boole-Bell type (in)equalities. (iii) Finally, so-called ``parameter cheats'' are introduced, whereby parameters are transformed bijectively and nonlinearly in such a way that classical systems mimic quantum correlations and vice versa. It is even possible to introduce parameter cheats which violate the Boole-Bell type inequalities stronger than quantum ones, thereby trespassing the Tsirelson limit. The price to be paid is nonuniformity.
Oliker, Leonid
of anthropogenic climate change are highly dependent on cloud-radiation interactions. In this paper, we Keywords Climate model, atmospheric general circulation model, finite volume model, global warming scientists today, with economic ramifications in the trillions of dollars. Effectively performing
System Advisor Model, SAM 2014.1.14: General Description
Blair, N.; Dobos, A. P.; Freeman, J.; Neises, T.; Wagner, M.; Ferguson, T.; Gilman, P.; Janzou, S.
2014-02-01T23:59:59.000Z
This document describes the capabilities of the U.S. Department of Energy and National Renewable Energy Laboratory's System Advisor Model (SAM), Version 2013.9.20, released on September 9, 2013. SAM is a computer model that calculates performance and financial metrics of renewable energy systems. Project developers, policy makers, equipment manufacturers, and researchers use graphs and tables of SAM results in the process of evaluating financial, technology, and incentive options for renewable energy projects. SAM simulates the performance of photovoltaic, concentrating solar power, solar water heating, wind, geothermal, biomass, and conventional power systems. The financial model can represent financial structures for projects that either buy and sell electricity at retail rates (residential and commercial) or sell electricity at a price determined in a power purchase agreement (utility). SAM's advanced simulation options facilitate parametric and sensitivity analyses, and statistical analysis capabilities are available for Monte Carlo simulation and weather variability (P50/P90) studies. SAM can also read input variables from Microsoft Excel worksheets. For software developers, the SAM software development kit (SDK) makes it possible to use SAM simulation modules in their applications written in C/C++, C#, Java, Python, and MATLAB. NREL provides both SAM and the SDK as free downloads at http://sam.nrel.gov. Technical support and more information about the software are available on the website.
System Advisor Model, SAM 2011.12.2: General Description
Gilman, P.; Dobos, A.
2012-02-01T23:59:59.000Z
This document describes the capabilities of the U.S. Department of Energy and National Renewable Energy Laboratory's System Advisor Model (SAM), Version 2011.12.2, released on December 2, 2011. SAM is software that models the cost and performance of renewable energy systems. Project developers, policy makers, equipment manufacturers, and researchers use graphs and tables of SAM results in the process of evaluating financial, technology, and incentive options for renewable energy projects. SAM simulates the performance of solar, wind, geothermal, biomass, and conventional power systems. The financial model can represent financing structures for projects that either buy and sell electricity at retail rates (residential and commercial) or sell electricity at a price determined in a power purchase agreement (utility). Advanced analysis options facilitate parametric, sensitivity, and statistical analyses, and allow for interfacing SAM with Microsoft Excel or with other computer programs. SAM is available as a free download at http://sam.nrel.gov. Technical support and more information about the software are available on the website.
Gamma-ray Burst Models: General Requirements and Predictions
P. Meszaros
1995-02-21T23:59:59.000Z
Whatever the ultimate energy source of gamma-ray bursts turns out to be, the resulting sequence of physical events is likely to lead to a fairly generic, almost unavoidable scenario: a relativistic fireball that dissipates its energy after it has become optically thin. This is expected both for cosmological and halo distances. Here we explore the observational motivation of this scenario, and the consequences of the resulting models for the photon production in different wavebands, the energetics and the time structure of classical gamma-ray bursters.
Novel Geometrical Models of Relativistic Stars. I. The General Scheme
P. P. Fiziev
2004-09-19T23:59:59.000Z
In a series of articles we describe a novel class of geometrical models of relativistic stars. Our approach to the static spherically symmetric solutions of Einstein equations is based on a careful physical analysis of radial gauge conditions. It brings us to a two parameter family of relativistic stars without stiff functional dependence between the stelar radius and stelar mass. It turns out that within this family there do exist relativistic stars with arbitrary large mass, which are to have arbitrary small radius and arbitrary small luminosity. In addition, point particle idealization, as a limiting case of bodies with finite dimension, becomes possible in GR, much like in Newton gravity.
Environmental Impact and Sustainability Applied General Equilibrium Model
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 You are beingZealand JumpConceptual Model,DOEHazel Crest,EnergySerranopolisEnviroMission Ltd JumpFund Place:
Inference for Clustered Mixed Outcomes from a Multivariate Generalized Linear Mixed Model
Chen, Hsiang-Chun
2013-08-01T23:59:59.000Z
) and E(?i2t?) with their marginal expectations over X, ??1 = EX {E(?i1t)} and ??2 = EX {E(?i2t)}, which are shown in the previous subsections. In other words, the overall total-CC is ?total = KtotalN,1,2 (??1, ??2) KtotalD,1,2 (??1, ??2) . 3.2.4....2 Multivariate Generalized Linear Mixed Model . . . . . . . . . . . . . 6 2.3 Assessing Correlation in Generalized Linear Mixed Model . . . . . . . 8 2.4 Bayesian Method for the Generalized Linear Mixed Model . . . . . . 10 3. ASSESSING CORRELATION...
Generalized models as a universal approach to the analysis of nonlinear dynamical systems
Thilo Gross; Ulrike Feudel
2006-01-29T23:59:59.000Z
We present a universal approach to the investigation of the dynamics in generalized models. In these models the processes that are taken into account are not restricted to specific functional forms. Therefore a single generalized models can describe a class of systems which share a similar structure. Despite this generality, the proposed approach allows us to study the dynamical properties of generalized models efficiently in the framework of local bifurcation theory. The approach is based on a normalization procedure that is used to identify natural parameters of the system. The Jacobian in a steady state is then derived as a function of these parameters. The analytical computation of local bifurcations using computer algebra reveals conditions for the local asymptotic stability of steady states and provides certain insights on the global dynamics of the system. The proposed approach yields a close connection between modelling and nonlinear dynamics. We illustrate the investigation of generalized models by considering examples from three different disciplines of science: a socio-economic model of dynastic cycles in china, a model for a coupled laser system and a general ecological food web.
Blei, David M.
a linear transformation of co- variates through a possibly non-linear link function to generate a response of generalized linear models (DP-GLMs), a Bayesian nonparametric regression model that combines the advantages of gen- eralized linear models with the flexibility of nonpara- metric regression. A DP-GLM produces
Option Pricing for GARCH-type Models with Generalized Hyperbolic Innovations
Boyer, Edmond
Option Pricing for GARCH-type Models with Generalized Hyperbolic Innovations Christophe Chorro on equity option books. Given the historical measure, the dynamics of assets are modeled by Garch, Incomplete markets, CAC 40, SP 500, GARCH-type models. JEL classification: G13, C22. The authors
Final Report: The Santa Barbara Channel - Santa Maria Basin Circulation Study
Winant, Clinton D; Dever, Edward P; Dorman, Clive E; Hendershott, Myrl C
2006-01-01T23:59:59.000Z
such as the wind stress that force the oceanic circulation.upwelling winds but the pressure gradient force dominatesforce that is generally poleward against the mean wind
Efficient Learning of Generalized Linear and Single Index Models with Isotonic Regression
Efficient Learning of Generalized Linear and Single Index Models with Isotonic Regression Sham M) provide powerful generalizations of linear regression, where the target variable is assumed to be a (possibly unknown) 1-dimensional function of a linear predictor. In gen- eral, these problems entail non
IWWWFB, Plitvice, Croatia 2007 Some aspects of a generalized Wagner model.
Paris-Sud XI, UniversitÃ© de
22nd IWWWFB, Plitvice, Croatia 2007 Some aspects of a generalized Wagner model. Malleron N and Floating Bodies, Plitvice : Croatia (2007)" #12; 22nd IWWWFB, Plitvice, Croatia 2007 The last condition
Karplus, V.J.
A well-known challenge in computable general equilibrium (CGE) models is to maintain correspondence between the forecasted economic and physical quantities over time. Maintaining such a correspondence is necessary to ...
Recurrence and non-ergodicity in generalized wind-tree models
Krzysztof Fr?czek; Pascal Hubert
2015-06-19T23:59:59.000Z
In this paper, we consider generalized wind-tree models and $\\Z^d$-covers over compact translation surfaces. Under suitable hypothesis, we prove recurrence of the linear flow in a generic direction and non-ergodicity of Lebesgue measure.
Parallel Simulation for a Fish Schooling Model on a General-Purpose Graphics Processing Unit
Li, Hong; Kolpas, Allison; Petzold, Linda; Moehlis, J
2009-01-01T23:59:59.000Z
Model on a General-Purpose Graphics Processing Unit Hong LiThe current generation of graphics processing units is well-we will describe how a Graphics Pro- cessor Unit (GPU) can
Large scale oceanic circulation and fluxes of freshwater, heat, nutrients and oxygen
Ganachaud, Alexandre Similien, 1970-
2000-01-01T23:59:59.000Z
A new, global inversion is used to estimate the large scale oceanic circulation based on the World Ocean Circulation Experiment and Java Australia Dynamic Experiment hydrographic data. A linear inverse "box" model is used ...
Independent review of SCDAP/RELAP5 natural circulation calculations
Martinez, G.M.; Gross, R.J.; Martinez, M.J.; Rightley, G.S.
1994-01-01T23:59:59.000Z
A review and assessment of the uncertainties in the calculated response of reactor coolant system natural circulation using the SCDAP/RELAP5 computer code were completed. The SCDAP/RELAP5 calculation modeled a station blackout transient in the Surry nuclear power plant and concluded that primary system depressurization from natural circulation induced primary system failure is more likely than previously thought.
Dynamics of the Thermohaline Circulation under Wind Forcing
Dynamics of the Thermohaline Circulation under Wind Forcing Hongjun Gao and Jinqiao Duan Â¡ 1 external wind forcing. We show that, when there is no wind forcing, the stream function and the density. With rapidly oscillating wind forcing, we obtain an averaging principle for the thermohaline circulation model
Dynamics of the Thermohaline Circulation under Wind Forcing
Dynamics of the Thermohaline Circulation under Wind Forcing Hongjun Gao 1 and Jinqiao Duan 2 1 external wind forcing. We show that, when there is no wind forcing, the stream function and the density. With rapidly oscillating wind forcing, we obtain an averaging principle for the thermohaline circulation model
Numerical Simulation of a Natural Circulation Steam Generator
WeinmÃ¼ller, Ewa B.
Numerical Simulation of a Natural Circulation Steam Generator W. Linzer \\Lambda , K. Ponweiser circulation steam generator. We focus on a model with a simple geometry consisting of two vertical pipes properties of water and steam. We present a numerical algorithm based on an explicit upwind discretization
Climate Determinism Revisited: Multiple Equilibria in a Complex Climate Model
Ferreira, David
Multiple equilibria in a coupled ocean–atmosphere–sea ice general circulation model (GCM) of an aquaplanet with many degrees of freedom are studied. Three different stable states are found for exactly the same set of ...
Kinetic Modeling Of Solid-Gas Reactions At Reactor Scale: A General Approach Loc Favergeon1
Paris-Sud XI, UniversitÃ© de
the knowledge of the kinetic model for the calculation of the speed of reaction in one part of the reactorKinetic Modeling Of Solid-Gas Reactions At Reactor Scale: A General Approach LoÃ¯c Favergeon1 favergeon@emse.fr ABSTRACT A rigorous simulation of industrial reactors in the case of solid-gas reacting
General Behavioral Thermal Modeling and Characterization for Multi-core Microprocessor Design
Tan, Sheldon X.-D.
General Behavioral Thermal Modeling and Characterization for Multi-core Microprocessor Design Thom-performance multi-core microprocessor design. The new approach builds the thermal behavioral models from ability. Experimental results on a real quad-core microprocessor show that ThermSID is more accurate than
Modeling benzene plume elongation mechanisms exerted by ethanol using RT3D with a general
Alvarez, Pedro J.
Modeling benzene plume elongation mechanisms exerted by ethanol using RT3D with a general substrate ethanol on benzene fate and transport in fuel-contaminated groundwater and to discern the most influential benzene plume elongation mechanisms. The model, developed as a module for the Reactive Transport in 3
Hsu, Sze-Bi
: 122 )1( 2 2 xK x =0 (i) Extinction case: species y wins Figure 12.1 In this case ),0( 22 KE())(),((lim 221 Ktxtx t . #12;(ii) Extinction case: species 1x win, Figure 12.2 In this case )0,( 11 KE§3.12 Competition models, Mutualism or Symbiosis The general n -species competition model
b quark Electric Dipole moment in the general two Higgs Doublet and three Higgs Doublet models
E. O. Iltan
2001-05-17T23:59:59.000Z
We study the Electric Dipole moment of b quark in the general two Higgs Doublet model (model III) and three Higgs Doublet model with O(2) symmetry in the Higgs sector. We analyse the dependency of this quantity to the new phase coming from the complex Yukawa couplings and masses of charged and neutral Higgs bosons. We see that the Electric Dipole moment of b quark is at the order of 10^{-20} e cm, which is an extremely large value compared to one calculated in the SM and also two Higgs Doublet model (model II) with real Yukawa couplings.
Schubert, Wayne H.
THESIS STEADY-STATE CIRCULATIONS FORCED BY DIABATIC HEATING AND WIND STRESS IN THE INTERTROPICAL-STATE CIRCULATIONS FORCED BY DIABATIC HEATING AND WIND STRESS IN THE INTERTROPICAL CONVERGENCE ZONE A number. The model is forced by prescribed diabatic heating and boundary layer wind stress curl. The circulations
Buoyancy-driven circulation in the Red Sea
Zhai, Ping, Ph. D. Massachusetts Institute of Technology
2014-01-01T23:59:59.000Z
This thesis explores the buoyancy-driven circulation in the Red Sea, using a combination of observations, as well as numerical modeling and analytical method. The first part of the thesis investigates the formation mechanism ...
The biogeochemistry and residual mean circulation of the southern ocean
Ito, Takamitsu, 1976-
2005-01-01T23:59:59.000Z
I develop conceptual models of the biogeochemistry and physical circulation of the Southern Ocean in order to study the air-sea fluxes of trace gases and biological productivity and their potential changes over ...
B. TRANSPORTATION, CIRCULATION AND PARKING B. TRANSPORTATION, CIRCULATION AND
Mullins, Dyche
B. TRANSPORTATION, CIRCULATION AND PARKING 231 B. TRANSPORTATION, CIRCULATION AND PARKING on transportation and connectivity issues common to UCSF as a whole. Please refer to Chapter 5, Plans for Existing characteristics specific to each individual UCSF site. DETERMINANTS OF THE 1996 LRDP The transportation
Exclusive $B \\to PV $ Decays and CP Violation in the General two-Higgs-doublet Model
Y. L. Wu; C. Zhuang
2007-01-10T23:59:59.000Z
We calculate all the branching ratios and direct CP violations of $B \\to PV$ decays in a most general two-Higgs-doublet model with spontaneous CP violation. As the model has rich CP-violating sources, it is shown that the new physics effects to direct CP violations and branching ratios in some channels can be significant when adopting the generalized factorization approach to evaluate the hadronic matrix elements, which provides good signals for probing new physics beyond the SM in the future B experiments.
A General Nonlinear Fluid Model for Reacting Plasma-Neutral Mixtures
Meier, E T; Shumlak, U
2012-04-06T23:59:59.000Z
A generalized, computationally tractable fluid model for capturing the effects of neutral particles in plasmas is derived. The model derivation begins with Boltzmann equations for singly charged ions, electrons, and a single neutral species. Electron-impact ionization, radiative recombination, and resonant charge exchange reactions are included. Moments of the reaction collision terms are detailed. Moments of the Boltzmann equations for electron, ion, and neutral species are combined to yield a two-component plasma-neutral fluid model. Separate density, momentum, and energy equations, each including reaction transfer terms, are produced for the plasma and neutral equations. The required closures for the plasma-neutral model are discussed.
Davydov, E A
2013-01-01T23:59:59.000Z
Nowadays it is widely accepted that the evolution of the universe was driven by some scalar degrees of freedom both on its early stage and at present. The corresponding cosmological models often involve some scalar fields introduced ad hoc. In this paper we cultivate a different approach, which is based on a derivation of new scalar degrees of freedom from fundamental modifications of Einstein's gravity. In elaboration of our previous work, we here investigate properties of the dilaton-scalar gravity obtained by dimensional reductions of a recently proposed affine generalized gravity theory. We show that these models possess the same symmetries as related models of GR with ordinary scalar fields. As a result, for a rather general class of dilaton-scalar gravity models we construct additional first integrals and formulate an integral equation well suited for solving by iterations.
Phase synchronization of coupled bursting neurons and the generalized Kuramoto model
Fabiano A. S. Ferrari; Ricardo L. Viana; Sérgio R. Lopes; Ruedi Stoop
2015-02-13T23:59:59.000Z
Bursting neurons fire rapid sequences of action potential spikes followed by a quiescent period. The basic dynamical mechanism of bursting is the slow currents that modulate a fast spiking activity caused by rapid ionic currents. Minimal models of bursting neurons must include both effects. We considered one of these models and its relation with a generalized Kuramoto model, thanks to the definition of a geometrical phase for bursting and a corresponding frequency. We considered neuronal networks with different connection topologies and investigated the transition from a non-synchronized to a partially phase-synchronized state as the coupling strength is varied. The numerically determined critical coupling strength value for this transition to occur is compared with theoretical results valid for the generalized Kuramoto model.
Jia, Yan-Bin
IEEE TRANSACTIONS ON ROBOTICS, VOL. 26, NO. 5, OCTOBER 2010 837 Modeling Deformations of General Parametric Shells Grasped by a Robot Hand Jiang Tian and Yan-Bin Jia, Member, IEEE Abstract--The robot hand and normal of the contact area. Design and analysis of a manipulation strategy thus depend on reliable
Generalized Disjunctive Programming as a Systematic Modeling Framework to Derive Scheduling
Grossmann, Ignacio E.
variables and constraints, but it may compromise computational performance. On the other hand, the convex hull reformulation is tighter, which generally helps to speed up the search procedure. GDP formulations. The best performer is, however, a multiple time grid model which can be derived from the convex hull
Towards a Generalized Regression Model for On-body Energy Prediction from Treadmill Walking
Sukhatme, Gaurav S.
Towards a Generalized Regression Model for On-body Energy Prediction from Treadmill Walking sensor data to energy expenditure is the ques- tion of normalizating across physiological parameters. Common approaches such as weight scaling require validation for each new population. An alternative
Calibration of CDO Tranches with the Dynamical Generalized-Poisson Loss Model
Brigo, Damiano
Calibration of CDO Tranches with the Dynamical Generalized-Poisson Loss Model (updated shortened, and consistent calibration to quoted index CDO tranches and tranchelets for several maturities is feasible, as we dynamics, investigating calibration improve- ments and stability. JEL classification code: G13. AMS
Tree-level unitarity constraints in the most general two Higgs doublet model
Ginzburg, I.F. [Sobolev Institute of Mathematics, acad. Koptyug avenue 4, 630090, Novosibirsk (Russian Federation); Ivanov, I.P. [Sobolev Institute of Mathematics, acad. Koptyug avenue 4, 630090, Novosibirsk (Russian Federation); INFN, Gruppo Collegato di Cosenza, Ponte Bucci, 31C, Dipartimento di Fisica, Universita della Calabria, Arcavacata di Rende (Serbia and Montenegro), 87036 (Italy)
2005-12-01T23:59:59.000Z
We obtain tree-level unitarity constraints for the most general Two-Higgs-Doublet Model (2HDM) with explicit CP-violation. We briefly discuss correspondence between possible violation of tree-level unitarity limitation and physical content of the theory.
Erratum to "Nonlinear Unmixing of Hyperspectral Images Using a Generalized Bilinear Model"
Dobigeon, Nicolas
1 Erratum to "Nonlinear Unmixing of Hyperspectral Images Using a Generalized Bilinear Model for the four images. TABLE I UNMIXING ALGORITHM PERFORMANCES WITH ACTUAL AND ESTIMATED ENDMEMBERS (1ST AND 2ND SCENARIOS): RE AND SAM. 1st scenario 2nd scenario RE (×10-2 ) SAM (×10-2 ) RE (×10-2 ) SAM (×10-2 ) LMM FM
Proton radioactivity within a generalized liquid drop model J. M. Dong,1
Paris-Sud XI, UniversitÃ© de
Proton radioactivity within a generalized liquid drop model J. M. Dong,1 H. F. Zhang,1 and G. Royer) The proton radioactivity half-lives of spherical proton emitters are investigated theoretically. The potential barriers preventing the emission of proton are determined in the quasimolecular shape path within
Tighter Relaxations for Higher-Order Models based on Generalized Roof Duality
Lunds Universitet
Tighter Relaxations for Higher-Order Models based on Generalized Roof Duality Johan Fredriksson one of the most successful approaches, namely roof duality, for approximately solving such problems cone. In the sec- ond method, it is shown that the roof dual bound can be applied in an iterated way
Computable General Equilibrium Models for the Analysis of Energy and Climate Policies
Wing, Ian Sue
Computable General Equilibrium Models for the Analysis of Energy and Climate Policies Ian Sue Wing of energy and environmental policies. Perhaps the most important of these applications is the analysis Change, MIT Prepared for the International Handbook of Energy Economics Abstract This chapter is a simple
Generalized Jackiw-Rebbi Model and Topological Classification of Free Fermion Insulators
O. Nganba Meetei; Archana Anandakrishnan
2014-06-02T23:59:59.000Z
We present a new perspective to the classification of topological phases in free fermion insulators by generalizing the Jackiw-Rebbi model to arbitrary dimensions. We show that a generalized Jackiw-Rebbi model where the Dirac mass ($m$) satisfies $m(x)=-m(-x)$ is invariant under a parity transformation ($P$) that relates the $x>0$ half to the $xtopological classification of free fermion insulators. Gapless edge states are a natural consequence of our construction and their topological nature can be understood from the fact that all gapless edge states at a given interface transform similarly under $P$ (all odd or all even). A naive non-topological model for states confined to the interface will allow both even and odd states.
Examining the Generalized Waring Model for the Analysis of Traffic Crashes
Peng, Yichuan
2013-05-03T23:59:59.000Z
characterized by heavy long tail (Guo and Trivedi, 2002). Third, many empirical crash data exhibit more zero observations than would be allowed by a NB regression model, which causes the low mean issue of traffic crash datasets. It is often difficult.... This kind of model has been extensively used in many areas (e.g. Ramaswamy et al., 1994; Wang et al., 1998; Guo & Trivedi, 2002)and has been proposed and applied in the traffic safety context recently (Park & Lord, 2010). The general model structure of a...
Top quark electric and chromo electric dipole moments in the general two Higgs Doublet model
E. O. Iltan
2002-02-11T23:59:59.000Z
We study the electric and chromo electric dipole moment of top quark in the general two Higgs Doublet model (model III). We analyse the dependency of this quantity to the new phases coming from the complex Yukawa couplings and masses of charged and neutral Higgs bosons. We observe that the electric and chromo elecric dipole moments of top quark are at the order of 10^{-21} e cm and 10^{-20} g_s cm, which are extremely large values compared to ones calculated in the SM and also two Higgs Doublet model with real Yukawa couplings.
A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
Bengt Gustafsson; Bengt Edvardsson; Kjell Eriksson; Uffe Graae Jorgensen; Aake Nordlund; Bertrand Plez
2008-05-05T23:59:59.000Z
We have constructed a grid of about 10,000 spherically symmetric and plane-parallel models with the MARCS program, and make it available for public use. Parameter ranges are: Teff=2500 to 8000 K, log g =log(GM/R2)= -1 to 5 (cgs) with various masses and radii, [Me/H]=-5 to +1, with [Alpha/Fe] = 0.0 and 0.4 and different choices of C and N abundances to also represent stars of types R, S and N, and with microturbulence parameters from 1 to 5 km/s. We also list fluxes in approximately 108,000 wavelength points. Underlying assumptions in addition to 1D stratification include hydrostatic equilibrium, MLT convection and LTE. A number of general properties of the models are discussed, in relation to the effects of changing blanketing and sphericity. Models are compared with other available grids and excellent agreement is found with plane-parallel models of Castelli and Kurucz within the overlapping parameter range. Although there are departures from the spherically symmetric NextGen models, the agreement with more recent PHOENIX models is gratifying. The models of the grid show regularities, but some interesting departures from general patterns occur for the coolest models due to the molecular opacities. We have tested rules of thumb concerning effects of blanketing and sphericity and found them to often be astonishingly accurate. Some interesting new phenomena have been discovered, such as the intricate coupling between blanketing and sphericity, and the strong effects of carbon enhancement on metal-poor models. We give further details of models and comparisons with observations in subsequent papers.
Agarwala, R. [National Institutes of Health, Bethesda, MD (United States); Batzoglou, S. [MIT, Cambridge, MA (United States); Dancik, V. [Univ. of Southern California, Los Angeles, CA (United States)] [and others
1997-06-01T23:59:59.000Z
We consider the problem of determining the three-dimensional folding of a protein given its one-dimensional amino acid sequence. We use the HP model for protein folding proposed by Dill, which models protein as a chain of amino acid residues that are either hydrophobic or polar, and hydrophobic interactions are the dominant initial driving force for the protein folding. Hart and Istrail gave approximation algorithms for folding proteins on the cubic lattice under HP model. In this paper, we examine the choice of a lattice by considering its algorithmic and geometric implications and argue that triangular lattice is a more reasonable choice. We present a set of folding rules for a triangular lattice and analyze the approximation ratio which they achieve. In addition, we introduce a generalization of the HP model to account for residues having different levels of hydrophobicity. After describing the biological foundation for this generalization, we show that in the new model we are able to achieve similar constant factor approximation guarantees on the triangular lattice as were achieved in the standard HP model. While the structures derived from our folding rules are probably still far from biological reality, we hope that having a set of folding rules with different properties will yield more interesting folds when combined.
Energy and agriculture in the Haitian economy: A computable general equilibrium model
Jones, D.W.; Wu, M.T.C.; Das, S.; Cohn, S.M.
1988-02-01T23:59:59.000Z
This report documents a computable general equilibrium (CGE) model of the economy of Haiti, emphasizing energy use in agriculture. CGE models compare favorably with econometric models for developing countries in terms of their ability to take advantage of available data. The model of Haiti contains ten production sectors: manufacturing, services, transportation, electricity, rice, coffee, sugar cane, sugar refining, general agriculture, and fuelwood and charcoal. All production functions use functional forms which permit factor substitution. Consumption is specified for three income categories of consumers and a government sector with a linear expenditure system (LES) of demand equations. The economy exports four categories of products and imports six. Balanced trade and capital accounts are required for equilibrium. Total sectoral allocations of land, labor and capital are constrained to equal the quantities of these inputs in the Haitian economy as of the early 1980s. The model can be used to study the consequences of fiscal and trade policies and sectorally oriented productivity improvement policies. Guidance is offered regarding how to use the model to study economic growth and technological change. Limitations of the mode are also pointed out as well as user strategies which can lessen or work around some of those limitations. 19 refs.
Atmospheric Circulation and Tides of "51Peg b-like" Planets
Adam P. Showman; Tristan Guillot
2002-02-12T23:59:59.000Z
We examine the properties of the atmospheres of extrasolar giant planets at orbital distances smaller than 0.1 AU from their stars. We show that these ``51Peg b-like'' planets are rapidly synchronized by tidal interactions, but that small departures from synchronous rotation can occur because of fluid-dynamical torques within these planets. Previous radiative-transfer and evolution models of such planets assume a homogeneous atmosphere. Nevertheless, we show using simple arguments that, at the photosphere, the day-night temperature difference and characteristic wind speeds may reach ~500 K and ~2 km/s, respectively. Substantial departures from chemical equilibrium are expected. The cloud coverage depends sensitively on the dynamics; clouds could exist predominantly either on the dayside or nightside, depending on the circulation regime. Radiative-transfer models that assume homogeneous conditions are therefore inadequate in describing the atmospheric properties of 51Peg b-like planets. We present preliminary three-dimensional, nonlinear simulations of the atmospheric circulation of HD209458b that indicate plausible patterns for the circulation and generally agree with our simpler estimates. Furthermore, we show that kinetic energy production in the atmosphere can lead to the deposition of substantial energy in the interior, with crucial consequences for the evolution of these planets. Future measurements of reflected and thermally-emitted radiation from these planets will help test our ideas.
Energy-Momentum of the Friedmann Models in General Relativity and Teleparallel Theory of Gravity
M. Sharif; M. Jamil Amir
2008-09-09T23:59:59.000Z
This paper is devoted to the evaluation of the energy-momentum density components for the Friedmann models. For this purpose, we have used M${\\o}$ller's pseudotensor prescription in General Relativity and a certain energy-momentum density developed from his teleparallel formulation. It is shown that the energy density of the closed Friedmann universe vanishes on the spherical shell at the radius $\\rho=2\\sqrt{3}$. This coincides with the earlier results available in the literature. We also discuss the energy of the flat and open models. A comparison shows a partial consistency between the M${\\o}$ller's pseudotensor for General Relativity and teleparallel theory. Further, it is shown that the results are independent of the free dimensionless coupling constant of the teleparallel gravity.
Forget, FranÃ§ois
, subgrid-scale topography parameterization, etc.) and at high altitude (gravity wave drag). In addition accurately in the absence of observations. Â¢ Now at Laboratoire d'Energie Solaire et Thermique de l Spectrometer (TES) and Pressure Modulated Infrared Radiometer (PMIRR) instru- ments of the Mars Global Surveyor
Lee, Jung-Eun; Johnson, Kathleen; Fung, Inez
2009-01-01T23:59:59.000Z
OF THE ‘‘AMOUNT EFFECT’’ Hoffmann, G. , M. Werner, and M.A. , A. N. LeGrande, and G. Hoffmann (2007), Water isotopeare prescribed as 0.5 [Hoffmann et al. , 1998] and 1.7% [
Fourier analysis for generalized cylinders with polar models of cross-sections
Forsythe, William Clarence
1990-01-01T23:59:59.000Z
. Background 1. 2. Modeling Criteria 1. 3. Modeling Methods 1. 3. 1. Voxel Methods 1. 3. 2. Constructive Solid Geometry 1. 3. 3. Boundary Representation 1. 3. 4. Superquadrics 1. 4. Generalized Cylinder 1. 4. 1. GC Definition 1. 4. 2. GC Research 1. 4. 3. GC... such as spheres, cuboids, and tetrahedrons. This method works well with man-made objects. For instance, a table may be represented with five cuboids, using one cuboid for the top of the table, and one cuboid each, positioned appropriately, for the four legs...
Allu, Srikanth [ORNL] [ORNL; Velamur Asokan, Badri [Exxon Mobil Research and Engineering] [Exxon Mobil Research and Engineering; Shelton, William A [Louisiana State University] [Louisiana State University; Philip, Bobby [ORNL] [ORNL; Pannala, Sreekanth [ORNL] [ORNL
2014-01-01T23:59:59.000Z
A generalized three dimensional computational model based on unied formulation of electrode- electrolyte-electrode system of a electric double layer supercapacitor has been developed. The model accounts for charge transport across the solid-liquid system. This formulation based on volume averaging process is a widely used concept for the multiphase ow equations ([28] [36]) and is analogous to porous media theory typically employed for electrochemical systems [22] [39] [12]. This formulation is extended to the electrochemical equations for a supercapacitor in a consistent fashion, which allows for a single-domain approach with no need for explicit interfacial boundary conditions as previously employed ([38]). In this model it is easy to introduce the spatio-temporal variations, anisotropies of physical properties and it is also conducive for introducing any upscaled parameters from lower length{scale simulations and experiments. Due to the irregular geometric congurations including porous electrode, the charge transport and subsequent performance characteristics of the super-capacitor can be easily captured in higher dimensions. A generalized model of this nature also provides insight into the applicability of 1D models ([38]) and where multidimensional eects need to be considered. In addition, simple sensitivity analysis on key input parameters is performed in order to ascertain the dependence of the charge and discharge processes on these parameters. Finally, we demonstarted how this new formulation can be applied to non-planar supercapacitors
Generalized Uncertainty Relations and Long Time Limits for Quantum Brownian Motion Models
C. Anastopoulos; J. J. Halliwell
1994-07-27T23:59:59.000Z
We study the time evolution of the reduced Wigner function for a class of quantum Brownian motion models. We derive two generalized uncertainty relations. The first consists of a sharp lower bound on the uncertainty function, $U = (\\Delta p)^2 (\\Delta q)^2 $, after evolution for time $t$ in the presence of an environment. The second, a stronger and simpler result, consists of a lower bound at time $t$ on a modified uncertainty function, essentially the area enclosed by the $1-\\sigma$ contour of the Wigner function. In both cases the minimizing initial state is a non-minimal Gaussian pure state. These generalized uncertainty relations supply a measure of the comparative size of quantum and thermal fluctuations. We prove two simple inequalites, relating uncertainty to von Neumann entropy, and the von Neumann entropy to linear entropy. We also prove some results on the long-time limit of the Wigner function for arbitrary initial states. For the harmonic oscillator the Wigner function for all initial states becomes a Gaussian at large times (often, but not always, a thermal state). We derive the explicit forms of the long-time limit for the free particle (which does not in general go to a Gaussian), and also for more general potentials in the approximation of high temperature.
Polvani, Lorenzo M.
[1] The effect of ozone depletion on temperature trends in the tropical lower stratosphere is explored with an atmospheric general circulation model, and directly contrasted to the effect of increased greenhouse gases and ...
Horizontal well circulation tool
Not Available
1990-11-06T23:59:59.000Z
This patent describes an apparatus for securement onto one end of a continuous length of remedial tubing introducible into a subterranean well and concentrically insertable through production tubing previously positioned within the well. The well having a deviated configuration including an entry portion communicating with a curved portion extending downwardly in the well from the entry portion, and a generally linear end portion traversable with a production formation.
A Generalized Linear Transport Model for Spatially-Correlated Stochastic Media
Anthony B. Davis; Feng Xu
2014-10-29T23:59:59.000Z
We formulate a new model for transport in stochastic media with long-range spatial correlations where exponential attenuation (controlling the propagation part of the transport) becomes power law. Direct transmission over optical distance $\\tau(s)$, for fixed physical distance $s$, thus becomes $(1+\\tau(s)/a)^{-a}$, with standard exponential decay recovered when $a\\to\\infty$. Atmospheric turbulence phenomenology for fluctuating optical properties rationalizes this switch. Foundational equations for this generalized transport model are stated in integral form for $d=1,2,3$ spatial dimensions. A deterministic numerical solution is developed in $d=1$ using Markov Chain formalism, verified with Monte Carlo, and used to investigate internal radiation fields. Standard two-stream theory, where diffusion is exact, is recovered when $a=\\infty$. Differential diffusion equations are not presently known when $a<\\infty$, nor is the integro-differential form of the generalized transport equation. Monte Carlo simulations are performed in $d=2$, as a model for transport on random surfaces, to explore scaling behavior of transmittance $T$ when transport optical thickness $\\tau_\\text{t} \\gg 1$. Random walk theory correctly predicts $T \\propto \\tau_\\text{t}^{-\\min\\{1,a/2\\}}$ in the absence of absorption. Finally, single scattering theory in $d=3$ highlights the model's violation of angular reciprocity when $a<\\infty$, a desirable property at least in atmospheric applications. This violation is traced back to a key trait of generalized transport theory, namely, that we must distinguish more carefully between two kinds of propagation: one that ends in a virtual or actual detection, the other in a transition from one position to another in the medium.
McManamay, Ryan A [ORNL
2014-01-01T23:59:59.000Z
Despite the ubiquitous existence of dams within riverscapes, much of our knowledge about dams and their environmental effects remains context-specific. Hydrology, more than any other environmental variable, has been studied in great detail with regard to dam regulation. While much progress has been made in generalizing the hydrologic effects of regulation by large dams, many aspects of hydrology show site-specific fidelity to dam operations, small dams (including diversions), and regional hydrologic regimes. A statistical modeling framework is presented to quantify and generalize hydrologic responses to varying degrees of dam regulation. Specifically, the objectives were to 1) compare the effects of local versus cumulative dam regulation, 2) determine the importance of different regional hydrologic regimes in influencing hydrologic responses to dams, and 3) evaluate how different regulation contexts lead to error in predicting hydrologic responses to dams. Overall, model performance was poor in quantifying the magnitude of hydrologic responses, but performance was sufficient in classifying hydrologic responses as negative or positive. Responses of some hydrologic indices to dam regulation were highly dependent upon hydrologic class membership and the purpose of the dam. The opposing coefficients between local and cumulative-dam predictors suggested that hydrologic responses to cumulative dam regulation are complex, and predicting the hydrology downstream of individual dams, as opposed to multiple dams, may be more easy accomplished using statistical approaches. Results also suggested that particular contexts, including multipurpose dams, high cumulative regulation by multiple dams, diversions, close proximity to dams, and certain hydrologic classes are all sources of increased error when predicting hydrologic responses to dams. Statistical models, such as the ones presented herein, show promise in their ability to model the effects of dam regulation effects at large spatial scales as to generalize the directionality of hydrologic responses.
General model selection estimation of a periodic regression with a Gaussian noise
Konev, Victor; 10.1007/s10463-008-0193-1
2010-01-01T23:59:59.000Z
This paper considers the problem of estimating a periodic function in a continuous time regression model with an additive stationary gaussian noise having unknown correlation function. A general model selection procedure on the basis of arbitrary projective estimates, which does not need the knowledge of the noise correlation function, is proposed. A non-asymptotic upper bound for quadratic risk (oracle inequality) has been derived under mild conditions on the noise. For the Ornstein-Uhlenbeck noise the risk upper bound is shown to be uniform in the nuisance parameter. In the case of gaussian white noise the constructed procedure has some advantages as compared with the procedure based on the least squares estimates (LSE). The asymptotic minimaxity of the estimates has been proved. The proposed model selection scheme is extended also to the estimation problem based on the discrete data applicably to the situation when high frequency sampling can not be provided.
Subin, Z.M.
2013-01-01T23:59:59.000Z
land model. J. Adv. Model. Earth Sys. Lee, S. -Y. , Chiang,in CESM1. J. Adv. Mod. Earth Sys. , In Press. Thompson, D.Analyses in the Community Earth System Model 1 (CESM1) By
T. P. Shestakova
2014-06-12T23:59:59.000Z
We construct Hamiltonian dynamics of the generalized spherically symmetric gravitational model in extended phase space. We start from the Faddeev - Popov effective action with gauge-fixing and ghost terms, making use of gauge conditions in differential form. It enables us to introduce missing velocities into the Lagrangian and then construct a Hamiltonian function according a usual rule which is applied for systems without constraints. The main feature of Hamiltonian dynamics in extended phase space is that it can be proved to be completely equivalent to Lagrangian dynamics derived from the effective action. We find a BRST invariant form of the effective action by adding terms not affecting Lagrangian equations. After all, we construct the BRST charge according to the Noether theorem. Our algorithm differs from that by Batalin, Fradkin and Vilkovisky, but the resulting BRST charge generates correct transformations for all gravitational degrees of freedom including gauge ones. Generalized spherically symmetric model imitates the full gravitational theory much better then models with finite number of degrees of freedom, so that one can expect appropriate results in the case of the full theory.
Research papers The vertical structure of time-mean estuarine circulation in a shallow,
Polton, Jeff
the mean fluid depth the residual circulation is well modelled by a water column of uniform density 2013 Accepted 5 March 2013 Available online 27 March 2013 Keywords: Tidal residual ROFI HF radar ADCP) model shows that the time-mean depth weighted flow, or the residual circulation, is usefully constrained
Modeling Climate and Production-related Impacts on Ice-core Beryllium-10
Modeling Climate and Production-related Impacts on Ice-core Beryllium-10 Christy Veeder Submitted Modeling Climate and Production-related Impacts on Ice-core Beryllium-10 Christy Veeder I use the Goddard Institute for Space Studies ModelE general circulation model to ex- amine the how beryllium-10, a cosmogenic
Lee, Shiu-Hang; Nagataki, Shigehiro
2012-01-01T23:59:59.000Z
To better model the efficient production of cosmic rays (CRs) in supernova remnants (SNRs) with the associated coupling between CR production and SNR dynamics, we have generalized an existing cr-hydro-NEI code (i.e., Ellison et al. 2012) to include the following processes: (1) an explicit calculation of the upstream precursor structure including the position dependent flow speed, density, temperature, and magnetic field strength; (2) a momentum and space dependent CR diffusion coefficient; (3) an explicit calculation of magnetic field amplification (MFA); (4) calculation of the maximum CR momentum using the amplified magnetic field; (5) a finite Alfven speed for the particle scattering centers; and (6) the ability to accelerate a superthermal seed population of CRs as well as the ambient thermal plasma. While a great deal of work has been done modeling SNRs, most work has concentrated on either the continuum emission from relativistic electrons or ions, or the thermal emission from the shock heated plasma. Ou...
Ozgur Akarsu; Tekin Dereli; Nihan Katirci; Mikhail B. Sheftel
2015-05-04T23:59:59.000Z
In a recent study Akarsu and Dereli (Gen. Relativ. Gravit. 45:1211, 2013) discussed the dynamical reduction of a higher dimensional cosmological model which is augmented by a kinematical constraint characterized by a single real parameter, correlating and controlling the expansion of both the external (physical) and internal spaces. In that paper explicit solutions were found only for the case of three dimensional internal space ($n=3$). Here we derive a general solution of the system using Lie group symmetry properties, in parametric form for arbitrary number $n=1,2,3,\\dots$ of internal dimensions. We also investigate the dynamical reduction of the model as a function of cosmic time $t$ for various values of $n$ and generate parametric plots to discuss cosmologically relevant results.
On the Patterns of Wind-Power Input to the Ocean Circulation
Roquet, Fabien
Pathways of wind-power input into the ocean general circulation are analyzed using Ekman theory. Direct rates of wind work can be calculated through the wind stress acting on the surface geostrophic flow. However, because ...
Quantum Analogical Modeling: A General Quantum Computing Algorithm for Predicting Language Behavior
Royal Skousen
2005-10-18T23:59:59.000Z
This paper proposes a general quantum algorithm that can be applied to any classical computer program. Each computational step is written using reversible operators, but the operators remain classical in that the qubits take on values of only zero and one. This classical restriction on the quantum states allows the copying of qubits, a necessary requirement for doing general classical computation. Parallel processing of the quantum algorithm proceeds because of the superpositioning of qubits, the only aspect of the algorithm that is strictly quantum mechanical. Measurement of the system collapses the superposition, leaving only one state that can be observed. In most instances, the loss of information as a result of measurement would be unacceptable. But the linguistically motivated theory of Analogical Modeling (AM) proposes that the probabilistic nature of language behavior can be accurately modeled in terms of the simultaneous analysis of all possible contexts (referred to as supracontexts) providing one selects a single supracontext from those supracontexts that are homogeneous in behavior (namely, supracontexts that allow no increase in uncertainty). The amplitude for each homogeneous supracontext is proportional to its frequency of occurrence, with the result that the probability of selecting one particular supracontext to predict the behavior of the system is proportional to the square of its frequency.
Degeneracies and scaling relations in general power-law models for gravitational lenses
Olaf Wucknitz
2002-02-20T23:59:59.000Z
The time delay in gravitational lenses can be used to derive the Hubble constant in a relatively simple way. The results of this method are less dependent on astrophysical assumptions than in many other methods. The most important uncertainty is related to the mass model used. We discuss a family of models with a separable radial power-law and an arbitrary angular dependence for the potential psi = r^beta * F(theta). Isothermal potentials are a special case of these models with beta=1. An additional external shear is used to take into account perturbations from other galaxies. Using a simple linear formalism for quadruple lenses, we can derive H0 as a function of the observables and the shear. If the latter is fixed, the result depends on the assumed power-law exponent according to H0 proportional to (2-beta)/beta. The effect of external shear is quantified by introducing a `critical shear' gamma_c as a measure for the amount of shear that changes the result significantly. The analysis shows, that in the general case H0 and gamma_c do not depend on the position of the lens galaxy. We discuss these results and compare with numerical models for a number of real lens systems.
Continuous Circulation System: a new enabling technology
Kenawy, Walid F.
2002-01-01T23:59:59.000Z
are caused by the interruption of the drilling-fluid circulation. This interruption normally occurs when making drillpipe connections. Interruption of circulation causes wellbore problems like ballooning of the well, gelation of drilling mud, and settling...
Pouly, Amaury; Graça, Daniel S
2012-01-01T23:59:59.000Z
\\emph{Are analog models of computations more powerful than classical models of computations?} From a series of recent papers, it is now clear that many realistic analog models of computations are provably equivalent to classical digital models of computations from a \\emph{computability} point of view. Take, for example, the probably most realistic model of analog computation, the General Purpose Analog Computer (GPAC) model from Claude Shannon, a model for Differential Analyzers, which are analog machines used from 1930s to early 1960s to solve various problems. It is now known that functions computable by Turing machines are provably exactly those that are computable by GPAC. This paper is about next step: understanding if this equivalence also holds at the \\emph{complexity} level. In this paper we show that the realistic models of analog computation -- namely the General Purpose Analog Computer (GPAC) -- can simulate Turing machines in a computationally efficient manner. More concretely we show that, modulo...
Wakamatsu, M.; Tsujimoto, H. [Department of Physics, Faculty of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)
2005-04-01T23:59:59.000Z
The theoretical predictions are given for the forward limit of the unpolarized spin-flip isovector generalized parton distribution function (E{sup u}-E{sup d})(x,{xi},t) within the framework of the chiral quark soliton model, with full inclusion of the polarization of Dirac sea quarks. We observe that [(H{sup u}-H{sup d})+(E{sup u}-E{sup d})](x,0,0) has a sharp peak around x=0, which we interpret as a signal of the importance of the pionic qq excitation with large spatial extension in the transverse direction. Another interesting indication given by the predicted distribution in combination with Ji's angular momentum sum rule is that the d quark carries more angular momentum than the u quark in the proton, which may have some relation with the physics of the violation of the Gottfried sum rule.
Effect of atomic spontaneous decay on entanglement in the generalized Jaynes-Cummings model
Hessian, H.A. [Faculty of Science Al-Azhar University, Nasr City, Cairo (Egypt)], E-mail: ammar_67@yahoo.com; Obada, A.-S.F. [Faculty of Science, Assiut University, Assiut (Egypt); Mohamed, A.-B.A. [Faculty of Science Al-Azhar University, Nasr City, Cairo (Egypt)
2010-03-15T23:59:59.000Z
Some aspects of the irreversible dynamics of a generalized Jaynes-Cummings model are addressed. By working in the dressed-state representation, it is possible to split the dynamics of the entanglement and coherence. The exact solution of the master equation in the case of a high-Q cavity with atomic decay is found. Effects of the atomic spontaneous decay on the temporal evolution of partial entropies of the atom or the field and the total entropy as a quantitative measure entanglement are elucidated. The degree of entanglement, through the sum of the negative eigenvalues of the partially transposed density matrix and the negative mutual information has been studied and compared with other measures.
Yock, Adam D., E-mail: ADYock@mdanderson.org; Kudchadker, Rajat J. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Rao, Arvind [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and the Graduate School of Biomedical Sciences, the University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and the Graduate School of Biomedical Sciences, the University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Dong, Lei [Scripps Proton Therapy Center, San Diego, California 92121 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Scripps Proton Therapy Center, San Diego, California 92121 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States); Beadle, Beth M.; Garden, Adam S. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)] [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Court, Laurence E. [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)] [Department of Radiation Physics and Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and The Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030 (United States)
2014-05-15T23:59:59.000Z
Purpose: The purpose of this work was to develop and evaluate the accuracy of several predictive models of variation in tumor volume throughout the course of radiation therapy. Methods: Nineteen patients with oropharyngeal cancers were imaged daily with CT-on-rails for image-guided alignment per an institutional protocol. The daily volumes of 35 tumors in these 19 patients were determined and used to generate (1) a linear model in which tumor volume changed at a constant rate, (2) a general linear model that utilized the power fit relationship between the daily and initial tumor volumes, and (3) a functional general linear model that identified and exploited the primary modes of variation between time series describing the changing tumor volumes. Primary and nodal tumor volumes were examined separately. The accuracy of these models in predicting daily tumor volumes were compared with those of static and linear reference models using leave-one-out cross-validation. Results: In predicting the daily volume of primary tumors, the general linear model and the functional general linear model were more accurate than the static reference model by 9.9% (range: ?11.6%–23.8%) and 14.6% (range: ?7.3%–27.5%), respectively, and were more accurate than the linear reference model by 14.2% (range: ?6.8%–40.3%) and 13.1% (range: ?1.5%–52.5%), respectively. In predicting the daily volume of nodal tumors, only the 14.4% (range: ?11.1%–20.5%) improvement in accuracy of the functional general linear model compared to the static reference model was statistically significant. Conclusions: A general linear model and a functional general linear model trained on data from a small population of patients can predict the primary tumor volume throughout the course of radiation therapy with greater accuracy than standard reference models. These more accurate models may increase the prognostic value of information about the tumor garnered from pretreatment computed tomography images and facilitate improved treatment management.
Meso-scale eects of tropical deforestation in Amazonia: preparatory LBA modelling studies
Paris-Sud XI, UniversitÃ© de
Meso-scale eects of tropical deforestation in Amazonia: preparatory LBA modelling studies A. J forest is good, above deforested areas (pasture) poor. The models' underestimate of the temperature Modelling studies with general circulation models have shown that large-scale deforestation of the Amazon
Memon, Atif M.
. The tests are built as sequences of keywords, and keywords are automatically translated into concrete lowModel-Based Testing with a General Purpose Keyword-Driven Test Automation Framework Tuomas Pajunen mika.katara@tut.fi Abstract--Model-based testing (MBT) is a relatively new approach to software testing
Validation of SSC using the FFTF natural-circulation tests
Horak, W.C.; Guppy, J.G.; Kennett, R.J.
1982-01-01T23:59:59.000Z
As part of the Super System Code (SSC) validation program, the 100% power FFTF natural circulation test has been simulated using SSC. A detailed 19 channel, 2 loop model was used in SSC. Comparisons showed SSC calculations to be in good agreement with the Fast Flux Test Facility (FFTF), test data. Simulation of the test was obtained in real time.
Dynamics of the stratospheric circulation response to climate change
Dynamics of the stratospheric circulation response to climate change Michael Sigmond, University the world have employed chemistry climate models (CCMs) to predict the future stratospheric dynamical (Eyring et al., 2005). Despite the abundance of simula- tions, however, many dynamical issues remain
Climate change impact on the Mediterranean Sea circulation
Ribes, AurÃ©lien
Climate change impact on the Mediterranean Sea circulation: a regional modelling approach Samuel number of studies about the stability of the THC in climate change scenario. A large range of climate Sea (Artegiani et al., 1997) which is the main source of the Eastern Mediterranean Deep Water. Past-climate
Lu, Jian; Sun, Lantao; Wu, Yutian; Chen, Gang
2014-03-15T23:59:59.000Z
The atmospheric circulation response to the global warming-like tropical upper tropospheric heating is revisited using a dry atmospheric general circulation model (AGCM) in light of a new diagnostics based on the concept of finite-amplitude wave activity (FAWA) on equivalent latitude. For a given tropical heating profile, the linear Wentzel-Kramers-Brillouin (WKB) wave refraction analysis sometimes gives a very different and even opposite prediction of the eddy momentum flux response to that of the actual full model simulation, exposing the limitation of the traditional linear approach in understanding the full dynamics of the atmospheric response under global warming. The implementation of the FAWA diagnostics reveals that in response to the upper tropospheric heating, effective diffusivity, a measure of the mixing efficiency, increases and advances upward and poleward in the subtropics and the resultant enhancement and the poleward encroachment of eddy potential vorticity mixing leads to a poleward displaced potential vorticity (PV) gradient peak in the upper troposphere. The anomalous eddy PV flux, in balance with the PV dissipation, gives rise to a poleward shift in the eddy-driven jet and eddy-driven mean meridional circulation. Sensitivity experiments show that these irreversible dissipation processes in the upper troposphere are robust, regardless of the width of the tropical heating.
atmospheric general circulation: Topics by E-print Network
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II. THE CLIMATIC SYSTEM Climate is defined is the basic engine which transforms solar heating into the energy of the atmospheric motions and determines Lucarini, Valerio...
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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 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization ofChemistryChristopher MoserLibrary
The generalized non-conservative model of a 1-planet system - revisited
Migaszewski, Cezary
2012-01-01T23:59:59.000Z
We study the long-term dynamics of a planetary system composed of a star and a planet. Both bodies are considered as extended, non-spherical, rotating objects. There are no assumptions made on the relative angles between the orbital angular momentum and the spin vectors of the bodies. Thus, we analyze full, spatial model of the planetary system. Both objects are assumed to be deformed due to their own rotations, as well as due to the mutual tidal interactions. The general relativity corrections are considered in terms of the post-Newtonian approximation. Besides the conservative contributions to the perturbing forces, there are also taken into account non-conservative effects, i.e., the dissipation of the mechanical energy. This dissipation is a result of the tidal perturbation on the velocity field in the internal zones with non-zero turbulent viscosity (convective zones). Our main goal is to derive the equations of the orbital motion as well as the equations governing time-evolution of the spin vectors (ang...
Bolshov, L.; Kondratenko, P.; Matveev, L.; Pruess, K.
2008-09-01T23:59:59.000Z
In this study, new elements were developed to generalize the dual-porosity model for moisture infiltration on and solute transport in unsaturated rocks, taking into account fractal aspects of the percolation process. Random advection was considered as a basic mechanism of solute transport in self-similar fracture systems. In addition to spatial variations in the infiltration velocity field, temporal fluctuations were also taken into account. The rock matrix, a low-permeability component of the heterogeneous geologic medium, acts as a trap for solute particles and moisture. Scaling relations were derived for the moisture infiltration flux, the velocity correlation length, the average velocity of infiltration, and the velocity correlation function. The effect of temporal variations in precipitation intensity on the infiltration processes was analyzed. It showed that the mode of solute transport is determined by the power exponent in the advection velocity correlation function and the dimensionality of the trapping system, both of which may change with time. Therefore, depending on time, various transport regimes may be realized: superdiffusion, subdiffusion, or classical diffusion. The complex structure of breakthrough curves from changes in the transport regimes was also examined. A renormalization of the solute source strength due to characteristic fluctuations of highly disordered media was established.
Intestinal circulation during inhalation anesthesia
Tverskoy, M.; Gelman, S.; Fowler, K.C.; Bradley, E.L.
1985-04-01T23:59:59.000Z
This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of /sub 86/Rb and 9-microns spheres labeled with /sup 141/Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. Halothane, enflurane, and isoflurane anesthesia were accompanied by a much lower arteriovenous oxygen content difference (AVDO/sub 2/) and oxygen uptake than pentobarbital or nitrous oxide. Compared with pentobarbital, enflurane anesthesia was not accompanied by marked differences in VR, F, Cl-Rb, and Cl-Sph; halothane at 2 MAC decreased VR and increased F and Cl-Rb while isoflurane increased VR and decreased F. alpha-Adrenoceptor blockade with phentolamine (1 mg . kg-1) abolished isoflurane-induced vasoconstriction, suggesting that the increase in VR was mediated via circulating catecholamines.
Sergei Rybalko; Ekaterina Zhuchkova
2006-03-15T23:59:59.000Z
We propose a quite general model of active media by consideration of the interaction between pacemakers via their phase response curves. This model describes a network of pulse oscillators coupled by their response to the internal depolarization of mutual stimulations. First, a macroscopic level corresponding to an arbitrary large number of oscillatory elements coupled globally is considered. As a specific and important case of the proposed model, the bidirectional interaction of two cardiac nodes is described. This case is generalized by means of an additional pacemaker, which can be expounded as an external stimulater. The behavior of such a system is analyzed. Second, the microscopic level corresponding to the representation of cardiac nodes by one-- and two--dimensional lattices of pulse oscillators coupled via the nearest neighbors is described. The model is a universal one in the sense that on its basis one can easily construct discrete distributed media of active elements, which interact via phase response curves.
Janson, Svante
Analyzing generalized Stirling permutations via relations to families of increasing trees and urn-mail: kuba@geometrie.tuwien.ac.at, Alois.Panholzer@tuwien.ac.at) Abstract. Stirling permutations are a class of multipermutations introduced by Gessel and Stanley. We consider Stirling permutations and generalizations
A generalized self consistent model for effective elastic moduli of human dentine
Qin, Qinghua
Consistent Model for cell model of fiber-reinforced composites is extended to the case of hollow cylinder model and the corresponding cell model is chosen to consist of a circular hollow cylinder filled from other models such as nano-indentation method. Ã? 2006 Elsevier Ltd. All rights reserved. Keywords
Jayaram, Bhyravabotla
Solvation Free Energy of Biomacromolecules: Parameters for a Modified Generalized Born Model provides rapid estimates of the electrostatic free energies of solvation for diverse molecules of parameters compatible with the AMBER force field is described. The method is used to estimate free energies
Mochrie, Simon
to form amyloid fibrils in vitro including acylphosphatase (Chiti et al., 2000), cold-shock proteinBiophysical Journal Volume 85 August 2003 11351144 1135 A General Model for Amyloid Fibril of fibrillar species formed during fibrillation of a-synuclein, insulin, and the B1 domain of protein G
Scott, Jeffery R.
The response of the ocean’s meridional overturning circulation (MOC) to increased greenhouse gas forcing is examined using a coupled model of intermediate complexity, including a dynamic 3D ocean subcomponent. Parameters ...
Wen, Caihong
2010-10-12T23:59:59.000Z
. Using this new 2-1/2-layer RGO model as a dynamical tool, a systematic investigation of the role of oceanic processes in controlling tropical Atlantic sea-surface temperature (SST) response to Atlantic Meridional Overturning Circulation (AMOC) changes...
Trampedach, Regner; Collet, Remo; Nordlund, Åke; Stein, Robert F
2013-01-01T23:59:59.000Z
Present grids of stellar atmosphere models are the workhorses in interpreting stellar observations, and determining their fundamental parameters. These models rely on greatly simplified models of convection, however, lending less predictive power to such models of late type stars. We present a grid of improved and more reliable stellar atmosphere models of late type stars, based on deep, 3D, convective, stellar atmosphere simulations. This grid is to be used in general for interpreting observations, and improve stellar and asteroseismic modeling. We solve the Navier Stokes equations in 3D and concurrent with the radiative transfer equation, for a range of atmospheric parameters, covering most of stellar evolution with convection at the surface. We emphasize use of the best available atomic physics for quantitative predictions and comparisons with observations. We present granulation size, convective expansion of the acoustic cavity, asymptotic adiabat, as function of atmospheric parameters. These and other re...
Thermodynamical description of modified generalized Chaplygin gas model of dark energy
H. Ebadi; H. Moradpour
2015-04-15T23:59:59.000Z
We consider a universe filled by a modified generalized Chaplygin gas together with a pressureless dark matter component. We get a thermodynamical interpretation for the modified generalized Chaplygin gas confined to the apparent horizon of FRW universe, whiles dark sectors do not interact with each other. Thereinafter, by taking into account a mutual interaction between the dark sectors of the cosmos, we find a thermodynamical interpretation for interacting modified generalized Chaplygin gas. Additionally, probable relation between the thermal fluctuations of the system and the assumed mutual interaction is investigated. Finally, we show that if one wants to solve the coincidence problem by using this mutual interaction, then the coupling constants of the interaction will be constrained. The corresponding constraint is also addressed. Moreover, the thermodynamic interpretation of using either a generalized Chaplygin gas or a Chaplygin gas to describe dark energy is also addressed throughout the paper.
A General Model of Concurrency and its Implementation as Many-core Dynamic RISC
Jesshope, Chris
scaling, good energy efficiency and tolerance to large latencies in asynchronous operations. This is true. This paper describes general-purpose solutions and builds on the premise that what is missing is a coherent
Wave Energy Converter (WEC) Array Effects on Wave Current and Sediment Circulation: Monterey Bay CA.
Roberts, Jesse D.; Jones, Craig; Magalen, Jason
2014-09-01T23:59:59.000Z
The goal s of this study were to develop tools to quantitatively characterize environments where wave energy converter ( WEC ) devices may be installed and to assess e ffects on hydrodynamics and lo cal sediment transport. A large hypothetical WEC array was investigated using wave, hydrodynamic, and sediment transport models and site - specific average and storm conditions as input. The results indicated that there were significant changes in sediment s izes adjacent to and in the lee of the WEC array due to reduced wave energy. The circulation in the lee of the array was also altered; more intense onshore currents were generated in the lee of the WECs . In general, the storm case and the average case show ed the same qualitative patterns suggesting that these trends would be maintained throughout the year. The framework developed here can be used to design more efficient arrays while minimizing impacts on nearshore environmen ts.
Improved Indoor Tracking Based on Generalized t-Distribution Noise Model
Shuo, Liu; Le, Yin; Khuen, Ho Weng; Voon, Ling Keck
2015-01-01T23:59:59.000Z
objective function. Industrial & engineering chemistryfunction approac. Industrial & Engineering Chem- istrynoise model. Industrial & Engineering Chemistry Research,
Plant Heterogeneity and Applied General Equilibrium Models of Trade: Lessons from
Stoiciu, Mihai
sector. I introduce these features by adapting a Hopenhayn (1992) model of plant entry and exit and embed a Hopenhayn (1992) model of firm entry and exit and embed this in a static multisector trade model with monop) develops a model with plant dynamics to match entry and exit rates in US manufacturing. I do
Downhole material injector for lost circulation control
Glowka, D.A.
1994-09-06T23:59:59.000Z
Apparatus and method are disclosed for simultaneously and separately emplacing two streams of different materials through a drill string in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drill string at the desired downhole location and harden only after mixing for control of a lost circulation zone. 6 figs.
Microfluidic Platforms for Capturing Circulating Tumor Cells
Tang, William C
Microfluidic Platforms for Capturing Circulating Tumor Cells Sweta Gupta, Allison C. Baker-cost microfluidic device that can be used to isolate and capture circulating tumor cells (CTCs) from whole blood. The device was made from polydimethylsiloxane (PDMS) consisting of a microfluidic channel with microposts
Downhole material injector for lost circulation control
Glowka, D.A.
1991-01-01T23:59:59.000Z
This invention is comprised of an apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.
Sillman, Sanford
Effects of cloud overlap in photochemical models Yan Feng, Joyce E. Penner, Sanford Sillman for radiation and cloud microphysics in general circulation models and for photolysis in photochemical transport their effects on averaged photolysis frequencies and OH concentrations in a global photochemical model
Heisenberg XXX Model with General Boundaries: Eigenvectors from Algebraic Bethe Ansatz
Samuel Belliard; Nicolas Crampé
2013-11-22T23:59:59.000Z
We propose a generalization of the algebraic Bethe ansatz to obtain the eigenvectors of the Heisenberg spin chain with general boundaries associated to the eigenvalues and the Bethe equations found recently by Cao et al. The ansatz takes the usual form of a product of operators acting on a particular vector except that the number of operators is equal to the length of the chain. We prove this result for the chains with small length. We obtain also an off-shell equation (i.e. satisfied without the Bethe equations) formally similar to the ones obtained in the periodic case or with diagonal boundaries.
Heisenberg XXX model with general boundaries: Eigenvectors from Algebraic Bethe ansatz
Belliard, S
2013-01-01T23:59:59.000Z
We propose a generalization of the algebraic Bethe ansatz to obtain the eigenvectors of the Heisenberg spin chain with general boundaries associated to the eigenvalues and the Bethe equations found recently by Cao et al. The ansatz takes the usual form of a product of operators acting on a particular vector except that the number of operators is equal to the length of the chain. We prove this result for the chains with small length. We obtain also an off-shell equation (i.e. satisfied without the Bethe equations) formally similar to the ones obtained in the periodic case or with diagonal boundaries.
Technical report on the General Electric model #1 electrostatic electron microscope
Druce, Albert J
1950-01-01T23:59:59.000Z
screen Vacuum Chamber' Figi 5. Sectionalized View of the Lens System of the General Electric Electron microscope. which is held in place with the micalex insulatoz s is a source of many difficulties. Ii' the combination of the insulators and central..., or if desired to give the beam a diverging angle with the optical axis. The filament of the General Electric Electron Gun is heated with 60 cycle alternating current. This gives rise to an alternat1ng field about the f1lament which will deflect...
Intelligent Allocation of Network Bandwidth: A Comparison of Two Generalized Particle Models
Lau, Francis C.M.
the allocation is not changed until the price reaches equilibrium. The other one is the economic generalized and further development of the OGPM, which comprises two major components: (1) dynamic allocation of network bandwidth based on GPM; and (2) dynamic modulation of price and demands of network bandwidth. The two
Daniel Gomez-Dumm; G. A. Gonzalez-Sprinberg
1999-05-03T23:59:59.000Z
The electric and weak electric dipole form factors for heavy fermions are calculated in the context of the most general two-Higgs-doublet model (2HDM). We find that the large top mass can produce a significant enhancement of the electric dipole form factor in the case of the b and c quarks. This effect can be used to distinguish between different 2HDM scenarios.
CIRCULATING MOVING BED COMBUSTION PROOF OF CONCEPT
Jukkola, Glen
2010-06-30T23:59:59.000Z
Circulating Moving Bed (CMB) combustion technology has its roots in traditional circulating fluidized bed technology and involves a novel method of solid fuel combustion and heat transfer. CMB technology represents a step change in improved performance and cost relative to conventional PC and FBC boilers. The CMB heat exchanger preheats the energy cycle working fluid, steam or air, to the high temperature levels required in systems for advanced power generation. Unique features of the CMB are the reduction of the heat transfer surfaces by about 60% as a result of the enhanced heat transfer rates, flexibility of operation, and about 30% lower cost over existing technology. The CMB Phase I project ran from July 2001 through March 2003. Its objective was to continue development of the CMB technology with a series of proof of concept tests. The tests were conducted at a scale that provided design data for scale up to a demonstration plant. These objectives were met by conducting a series of experiments in ALSTOM Power’s Multi-use Test Facility (MTF). The MTF was modified to operate under CMB conditions of commercial interest. The objective of the tests were to evaluate gas-to-solids heat transfer in the upper furnace, assess agglomeration in the high temperature CMB bubbling bed, and evaluate solids-to-tube heat transfer in the moving bed heat exchanger. The Phase I program results showed that there are still some significant technical uncertainties that needed to be resolved before the technology can be confidently scaled up for a successful demonstration plant design. Work remained in three primary areas: • scale up of gas to solid heat transfer • high temperature finned surface design • the overall requirements of mechanical and process design. The CMB Phase II workscope built upon the results of Phase I and specifically addressed the remaining technical uncertainties. It included a scaled MTF heat transfer test to provide the necessary data to scale up gas-to-solids heat transfer. A stress test rig was built and tested to provide validation data for a stress model needed to support high temperature finned surface design. Additional cold flow model tests and MTF tests were conducted to address mechanical and process design issues. This information was then used to design and cost a commercial CMB design concept. Finally, the MBHE was reconfigured into a slice arrangement and tested for an extended duration at a commercial CFB plant.
Dynamic Switching of the Spin Circulation in Tapered Magnetic...
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Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Print Monday, 22 April 2013 12:09...
assisted circulation: Topics by E-print Network
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Matt 19 Circulation (Cont) Means of Transferring Heat Physics Websites Summary: h 12;Earth Global Circulation (Cont.) Note: When a cold air mass and a warm air mass...
anterior circulation aneurysms: Topics by E-print Network
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97 Circulation (Cont) Means of Transferring Heat Physics Websites Summary: h 12;Earth Global Circulation (Cont.) Note: When a cold air mass and a warm air mass...
anterior circulation strokes: Topics by E-print Network
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53 Circulation (Cont) Means of Transferring Heat Physics Websites Summary: h 12;Earth Global Circulation (Cont.) Note: When a cold air mass and a warm air mass...
arterial coronary circulation: Topics by E-print Network
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119 Circulation (Cont) Means of Transferring Heat Physics Websites Summary: h 12;Earth Global Circulation (Cont.) Note: When a cold air mass and a warm air mass...
anterior circulation revascularization: Topics by E-print Network
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A 20 Circulation (Cont) Means of Transferring Heat Physics Websites Summary: h 12;Earth Global Circulation (Cont.) Note: When a cold air mass and a warm air mass...
Xing-Hai Zhang; Su-Peng Kou
2012-05-30T23:59:59.000Z
In this paper, we studied a generalized Bose-Hubbard model on a checkerboard lattice with topologically nontrivial flat-band. We used mean-field method to decouple the model Hamiltonian and obtained phase diagram by Landau theory of second-order phase transition. We further calculate the energy gap and the dispersion of quasi-particle or quasi-hole in Mott insulator state and found that in strong interaction limit the quasi-particles or the quasi-holes also have flat bands.
Ramon Herrera; Nelson Videla; Marco Olivares
2014-10-14T23:59:59.000Z
A warm inflationary universe scenario on a warped Dvali-Gabadadze-Porrati brane during intermediate inflation is studied. We consider a general form for the dissipative coefficient $\\Gamma(T,\\phi)\\propto T^{m}/\\phi^{m-1}$, and also study this model in the weak and strong dissipative regimes. We analyze the evolution of the universe in the slow-roll approximation, and find the exact solutions to the equations of motion. In both regimes, we utilize recent data from the BICEP2 experiment and also from the Planck satellite to constrain the parameters in our model in accordance with the theory of cosmological perturbations.
RF power recovery feedback circulator
Sharamentov, Sergey I. (Bolingbrook, IL)
2011-03-29T23:59:59.000Z
A device and method for improving the efficiency of RF systems having a Reflective Load. In the preferred embodiment, Reflected Energy from a superconducting resonator of a particle accelerator is reintroduced to the resonator after the phase of the Reflected Energy is aligned with the phase of the Supply Energy from a RF Energy Source. In one embodiment, a Circulator is used to transfer Reflected Energy from the Reflective Load into a Phase Adjuster which aligns the phase of the Reflected Energy with that of the Supply Energy. The phase-aligned energy is then combined with the Supply Energy, and reintroduced into the Reflective Load. In systems having a constant phase shift, the Phase Adjuster may be designed to shift the phase of the Reflected Energy by a constant amount using a Phase Shifter. In systems having a variety (variable) phase shifts, a Phase Shifter controlled by a phase feedback loop comprising a Phase Detector and a Feedback Controller to account for the various phase shifts is preferable.
Improved Indoor Tracking Based on Generalized t-Distribution Noise Model
Shuo, Liu; Le, Yin; Khuen, Ho Weng; Voon, Ling Keck
2015-01-01T23:59:59.000Z
log-distance path loss model (PLM) is commonly used [20]. Itclustered near the fitted PLM curve. B. Tracking of A Moving
V. R. Gavrilov; V. N. Melnikov
1998-01-13T23:59:59.000Z
The D-dimensional cosmological model on the manifold $M = R \\times M_{1} \\times M_{2}$ describing the evolution of 2 Einsteinian factor spaces, $M_1$ and $M_2$, in the presence of multicomponent perfect fluid source is considered. The barotropic equation of state for mass-energy densities and the pressures of the components is assumed in each space. When the number of the non Ricci-flat factor spaces and the number of the perfect fluid components are both equal to 2, the Einstein equations for the model are reduced to the generalized Emden-Fowler (second-order ordinary differential) equation, which has been recently investigated by Zaitsev and Polyanin within discrete-group analysis. Using the integrable classes of this equation one generates the integrable cosmological models. The corresponding metrics are presented. The method is demonstrated for the special model with Ricci-flat spaces $M_1,M_2$ and the 2-component perfect fluid source.
A new general model with non-spherical interactions for dense polymer systems and a
Heermann, Dieter W.
parametrization for Bisphenol-A-Polycarbonate Klaus M. Zimmer, Andreas Linke and Dieter W. Heermann Institut fur modeling of the monomer units. We apply the model to the special case of Bisphenol-A-Polycarbonate BPA on the thermodynamic properties of polycarbonate systems. We will also present properties and e ciency considerations
Ghan, S.J.; MacCracken, M.C.; Walton, J.J.
1985-08-01T23:59:59.000Z
An atmospheric general circulation model (AGCM) has been initialized with a 150 Tg summertime injection of smoke from post-war fires over Europe, Asia and North America. The smoke is subject to large-scale and convectice transport, dry deposition, coagulation and precipitation scavenging. The Hadley circulation is shown to respond in three stages. In the first stage, which lasts about one week depending on initial conditions, the Hadley circulation doubles in intensity. As the smoke spreads across the equator, and as the troposphere becomes more stable, the Hadley cell then weakens until it becomes actually weaker than in the control climate. In the final stage, as the smoke is removed, the Hadley cell gradually returns towards the control. Surface precipitation generally decreases as a result of the smoke. By the fourth week following the injection, zonal-mean surface precipitation in the tropics and summer hemisphere midlatitudes are about half of those in the control climate. The decrease is most notable over land, ocean precipitation being reduced only in the tropics. Penetrating convective precipitation is greatly reduced at all latitudes; large-scale precipitation is enhanced, becoming the dominant mode of precipitation in the simulation. Precipitation scavenging is shown to be the dominant removal process for particles larger than one micron in diameter. As a result, the lifetime of large particles increases several-fold due to the reduction in precipitation and the ''self-lofting'' of the smoke. For particles smaller than one micron in diameter, precipitation scavenging is found to be a much less efficient removal mechanism than both coagulation, which is important during the first week following the injection, and dry deposition at later times. 16 refs., 23 figs.
A Flexible Climate Model For Use In Integrated Assessments Andrei P. Sokolov and Peter H. Stone
penetration into the deep ocean is comparable with that of other significant uncertainties. 1. Introduction with coupled atmosphere ocean general circulation models (AOGCMs) because of their tremendous computer resource with a diffusive ocean model developed for use in the integrated framework of the MIT Joint Program on the Science
The aerodynamic characteristics of an airfoil utilizing boundary layer and circulation control
Boothe, Edward Milton
1965-01-01T23:59:59.000Z
THE AERODYNAMIC CHARACTERISTICS OF AN AIRFOIL UTILIZING BOUNDARY LAYER AND CIRCULATION CONTROL A Thesis By EDWARD MILTON BOOTHE Submitted to the Graduate College of the Texas ARM University in partial fulfillment of the requirements... . Wind Tunnel IV Auxiliary Equipment EXPERIMENTAL PROCEDURES . 13 Preliminary Tests 13 Measurement of Boundary Layer And Circulation Control Parameters 16 Wind Tunnel Tests of Airfoil Model. 19 Reduction of Experimental Results 20 V RESULTS...
Superconformal generalization of the chaotic inflation model ?/4?{sup 4} - ?/2?{sup 2}R
Kallosh, Renata; Linde, Andrei, E-mail: kallosh@stanford.edu, E-mail: alinde@stanford.edu [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA 94305 (United States)
2013-06-01T23:59:59.000Z
A model of chaotic inflation based on the theory of a scalar field with potential ??{sup 4} perfectly matches the observational data if one adds to it a tiny non-minimal coupling to gravity -?/2?{sup 2} R with ??>0.002. We describe embedding of this model into the superconformal theory with spontaneous breaking of superconformal symmetry, and into supergravity. A model with small ? is technically natural: setting the small parameter ? to zero leads to a point of enhanced symmetry in the underlying superconformal theory.
Competing mechanisms of chiral symmetry breaking in a generalized Gross-Neveu model
Boehmer, Christian; Thies, Michael [Institut fuer Theoretische Physik III, Universitaet Erlangen-Nuernberg, D-91058 Erlangen (Germany)
2010-05-15T23:59:59.000Z
Chiral symmetry of the 2-dimensional chiral Gross-Neveu model is broken explicitly by a bare mass term as well as a splitting of scalar and pseudoscalar coupling constants. The vacuum and light hadrons--mesons and baryons which become massless in the chiral limit--are explored analytically in leading order of the derivative expansion by means of a double sine-Gordon equation. Depending on the parameters, this model features new phenomena as compared to previously investigated 4-fermion models: spontaneous breaking of parity, a nontrivial chiral vacuum angle, twisted kinklike baryons whose baryon number reflects the vacuum angle, crystals with alternating baryons, and appearance of a false vacuum.
James, Stephen M.
2011-08-08T23:59:59.000Z
-dimensional axisymmetric beam-element code. ANSYS is used as a code to build three-dimensional non-axisymmetric solid-element casing models. The work done in this thesis opens the scope to incorporate complex non-axisymmetric casing models with XLTRC2....
James, Stephen M.
2011-08-08T23:59:59.000Z
The subject of this thesis is an extension of a two-dimensional, axisymmetric, Timoshenko-beam finite-element rotordynamic code to include a three-dimensional non-axisymmetric solid-element casing model. Axisymmetric beams are sufficient to model...
Circulating Fluidized Bed Combustion Boiler Project
Farbstein, S. B.; Moreland, T.
1984-01-01T23:59:59.000Z
The project to build a PYROFLOW circulating fluidized bed combustion (FBC) boiler at the BFGoodrich Chemical Plant at Henry, Illinois, is described. This project is being partially funded by Illinois to demonstrate the feasibility of utilizing high...
Circulation and convection in the Irminger Sea
Våge, Kjetil
2010-01-01T23:59:59.000Z
Aspects of the circulation and convection in the Irminger Sea are investigated using a variety of in-situ, satellite, and atmospheric reanalysis products. Westerly Greenland tip jet events are intense, small-scale wind ...
Cosmological Imprints of a Generalized Chaplygin Gas Model for the Early Universe
Bouhmadi-Lopez, Mariam; /Lisbon, CENTRA; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC; Liu, Yen-Wei; /Taiwan, Natl. Taiwan U.
2012-06-06T23:59:59.000Z
We propose a phenomenological model for the early universe where there is a smooth transition between an early quintessence phase and a radiation-dominated era. The matter content is modeled by an appropriately modified Chaplygin gas for the early universe. We constrain the model observationally by mapping the primordial power spectrum of the scalar perturbations to the latest data of WMAP7. We compute as well the spectrum of the primordial gravitational waves as would be measured today. We show that the high frequencies region of the spectrum depends on the free parameter of the model and most importantly this region of the spectrum can be within the reach of future gravitational waves detectors.
OLAF _ A General Modeling System to Evaluate and Optimize the Location of an Air
Fliege, Jörg
........................17 3.1.1The Standard Model ....................17 3.1.2Metabolism.1.2The Objective Function ..................40 5.1.3The Gradient of the Objective Function
A general model of resource production and exchange in systems of interdependent specialists.
Conrad, Stephen Hamilton; Finley, Patrick D.; Beyeler, Walter Eugene; Brown, Theresa Jean; Glass, Robert John, Jr.; Breen, Peter; Kuypers, Marshall; Norton, Matthew David; Quach, Tu-Thach; Antognoli, Matthew; Mitchell, Michael David
2011-11-01T23:59:59.000Z
Infrastructures are networks of dynamically interacting systems designed for the flow of information, energy, and materials. Under certain circumstances, disturbances from a targeted attack or natural disasters can cause cascading failures within and between infrastructures that result in significant service losses and long recovery times. Reliable interdependency models that can capture such multi-network cascading do not exist. The research reported here has extended Sandia's infrastructure modeling capabilities by: (1) addressing interdependencies among networks, (2) incorporating adaptive behavioral models into the network models, and (3) providing mechanisms for evaluating vulnerability to targeted attack and unforeseen disruptions. We have applied these capabilities to evaluate the robustness of various systems, and to identify factors that control the scale and duration of disruption. This capability lays the foundation for developing advanced system security solutions that encompass both external shocks and internal dynamics.
Self-repelling fractional Brownian motion - a generalized Edwards model for chain polymers
Jinky Bornales; Maria João Oliveira; Ludwig Streit
2011-12-10T23:59:59.000Z
We present an extension of the Edwards model for conformations of individual chain molecules in solvents in terms of fractional Brownian motion, and discuss the excluded volume effect on the end-to-end length of such trajectories or molecules.
General calculation model for reflection and transmission matrices of nanowire end facets
Svendsen, Guro K; Skaar, Johannes
2010-01-01T23:59:59.000Z
Nanowires show a large potential for various electrooptical devices, such as light emitting diodes, solar cells and nanowire lasers. We present a direct method developed to calculate the modal reflection and transmission matrix at the end facets of a waveguide of arbitrary cross section, resulting in a generalized version of the Fresnel equations. The reflection can be conveniently computed using Fast Fourier Transforms. We demonstrate that the reflection is qualitatively described by two main parameters, the modal field confinement and the average Fresnel reflection of the plane waves constituting the waveguide mode.
Enabling Differentiated Services Using Generalized Power Control Model in Optical Networks
Zhu, Quanyan
2011-01-01T23:59:59.000Z
This paper considers a generalized framework to study OSNR optimization-based end-to-end link level power control problems in optical networks. We combine favorable features of game-theoretical approach and central cost approach to allow different service groups within the network. We develop solutions concepts for both cases of empty and nonempty feasible sets. In addition, we derive and prove the convergence of a distributed iterative algorithm for different classes of users. In the end, we use numerical examples to illustrate the novel framework.
General model of phospholipid bilayers in fluid phase within the single chain mean field theory
Guo, Yachong; Baulin, Vladimir A. [Departament d’Enginyeria Química, Universitat Rovira i Virgili, Av. dels Paisos Catalans 26, 43007 Tarragona (Spain)] [Departament d’Enginyeria Química, Universitat Rovira i Virgili, Av. dels Paisos Catalans 26, 43007 Tarragona (Spain); Pogodin, Sergey [Institute of Chemical Research of Catalonia, ICIQ, Av. Paisos Catalans 16, 43007 Tarragona (Spain)] [Institute of Chemical Research of Catalonia, ICIQ, Av. Paisos Catalans 16, 43007 Tarragona (Spain)
2014-05-07T23:59:59.000Z
Coarse-grained model for saturated phospholipids: 1,2-didecanoyl-sn-glycero-3-phosphocholine (DCPC), 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC), 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and unsaturated phospholipids: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), 1,2- dioleoyl-sn-glycero-3-phosphocholine (DOPC) is introduced within the single chain mean field theory. A single set of parameters adjusted for DMPC bilayers gives an adequate description of equilibrium and mechanical properties of a range of saturated lipid molecules that differ only in length of their hydrophobic tails and unsaturated (POPC, DOPC) phospholipids which have double bonds in the tails. A double bond is modeled with a fixed angle of 120°, while the rest of the parameters are kept the same as saturated lipids. The thickness of the bilayer and its hydrophobic core, the compressibility, and the equilibrium area per lipid correspond to experimentally measured values for each lipid, changing linearly with the length of the tail. The model for unsaturated phospholipids also fetches main thermodynamical properties of the bilayers. This model is used for an accurate estimation of the free energies of the compressed or stretched bilayers in stacks or multilayers and gives reasonable estimates for free energies. The proposed model may further be used for studies of mixtures of lipids, small molecule inclusions, interactions of bilayers with embedded proteins.
Razzaghi, N
2015-01-01T23:59:59.000Z
We propose a phenomenological model of the Dirac neutrino mass matrix based on the Fridberg-Lee neutrino mass model at a special point. In this case, the Fridberg-Lee model reduces to the Democratic mass matrix with the $S_3$ permutation family symmetry. The Democratic mass matrix has an experimentally unfavored degenerate mass spectrum on the base of tribimaximal mixing matrix. We rescue the model to find a nondegenerate mass spectrum by adding the breaking mass term as preserving the twisted Fridberg-Lee symmetry. The tribimaximal mixing matrix can be also realized. Exact tribimaximal mixing leads to $\\theta_{13}=0$. However, the results from Daya Bay and RENO experiments have established a nonzero value for $\\theta_{13}$. Keeping the leading behavior of $U$ as tribimaximal, we use Broken Democratic neutrino mass model. We characterize a perturbation mass matrix which is responsible for a nonzero $\\theta_{13}$ along with CP violation, besides the solar neutrino mass splitting has been resulted from it. We c...
Agarwala, R. [National Institutes of Health, Bethesda, MD (United States); Batzoglou, S. [MIT Lab. for Computer Science, Cambridge, MA (United States); Dancik, V. [Univ. of Southern California, Los Angeles, CA (United States)] [and others
1997-12-01T23:59:59.000Z
A long standing problem in molecular biology is to determine the three-dimensional structure of a protein, given its amino acid sequence. A variety of simplifying models have been proposed abstracting only the {open_quotes}essential physical properties{close_quotes} of real proteins. In these models, the three dimensional space is often represented by a lattice. Residues which are adjacent in the primary sequence (i.e. covalently linked) must be placed at adjacent points in the lattice. A conformation of a protein is simply a self-avoiding walk along the lattice. The protein folding problem STRING-FOLD is that of finding a conformation of the protein sequence on the lattice such that the overall energy is minimized, for some reasonable definition of energy. This formulation leaves open the choices of a lattice and an energy function. Once these choices are made, one may then address the algorithmic complexity of optimizing the energy function for the lattice. For a variety of such simple models, this minimization problem is in fact NP-hard. In this paper, we consider the Hydrophobic-Polar (HP) Model introduced by Dill. The HP model abstracts the problem by grouping the 20 amino acids into two classes: hydrophobic (or non-polar) residues and hydrophilic (or polar) residues. For concreteness, we will take our input to be a string from (H,P){sup +}, where P represents polar residues, and H represents hydrophobic residues. Dill et.al. survey the literature analyzing this model. 8 refs., 2 figs., 1 tab.
Internal noise driven generalized Langevin equation from a nonlocal continuum model
Saikat Sarkar; Shubhankar Roy Chowdhury; Debasish Roy; Ram Mohan Vasu
2015-03-10T23:59:59.000Z
Starting with a micropolar formulation, known to account for nonlocal microstructural effects at the continuum level, a generalized Langevin equation (GLE) for a particle, describing the predominant motion of a localized region through a single displacement degree-of-freedom (DOF), is derived. The GLE features a memory dependent multiplicative or internal noise, which appears upon recognising that the micro-rotation variables possess randomness owing to an uncertainty principle. Unlike its classical version, the new GLE qualitatively reproduces the experimentally measured fluctuations in the steady-state mean square displacement of scattering centers in a polyvinyl alcohol slab. The origin of the fluctuations is traced to nonlocal spatial interactions within the continuum. A constraint equation, similar to a fluctuation dissipation theorem (FDT), is shown to statistically relate the internal noise to the other parameters in the GLE.
Separating expansion from contraction: generalized TOV condition, LTB models with pressure and CDM
Paris-Sud XI, UniversitÃ© de
, we adopt the Generalised PainlevÃ©-Gullstrand (hereafter GPG) formalism used in Lasky & Lun [6], which TO LTB MODELS IN GPG SYSTEM We consider a spherically symmetric Generalised LemaÃ®tre-Tolman-Bondi metric to include pressure. Performing an ADM 3+1 splitting in the GPG coordinates [6] , the metric reads ds2 = -(t
Description of FLIPSIM V: a General Firm Level Policy Simulation Model.
Richardson, James W.; Nixon, Clair J.
1986-01-01T23:59:59.000Z
................................................ 25 Subroutine FINAN .. .. ............................ . ................ 26 Subroutine LANDVL ............................................... 26 Subroutine DEPREC .............. . ................................. 27 Subroutine LEASE... the flexibility to lease farm machinery, and (g) adding a quadratic programming algorithm to determine crop mix. The model was .developed to allow analysis of the probable consequences of' alternative farm policies and income tax developments on typical...
A Generalized Cohesive Zone Model of Peel Test for Pressure Sensitive Adhesives
Zhang, Liang
2010-01-16T23:59:59.000Z
study, the mechanics of the peel test is analyzed based on a cohesive zone model. Cohesive failure is assumed to prevail in the vicinity of the peel front, that is, the adhesive fails not by debonding from the adherends but by splitting of the adhesive...
G. Dillon; G. Morpurgo
2010-01-26T23:59:59.000Z
After summarizing the basic points of the general QCD parametrization (GP) we discuss systematically its applications to the properties of the lowest families of baryons and mesons. We show how the hierarchy of the parameters in the GP emerges clearly in the properties of hadrons. Among other things, it explains why simple models can work reasonably well and clarifies the relationship between current and constituent quarks. More details on the hadron properties discussed with the GP appear from the list of secrions at the beginning of the paper.
E. O. Iltan
2001-05-17T23:59:59.000Z
We calculate the electric dipole moment of electron using the experimental result of muon electric dipole moment and upper limit of the BR(\\mu --> e\\gamma) in the framework of the general two Higgs doublet model. Our prediction is 10^{-32} e-cm, which lies in the experimental current limits. Further, we obtain constraints for the Yukawa couplings \\bar{\\xi}^{D}_{N,\\tau e} and \\bar{\\xi}^{D}_{N,\\tau\\mu}. Finally we present an expression which connects the BR(\\tau\\to \\mu\\gamma) and the electric dipole moment of \\tau-lepton and study the relation between these physical quantities.
ISO-SWS calibration and the accurate modelling of cool-star atmospheres - II. General results
L. Decin; B. Vandenbussche; C. Waelkens; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval; K. Hinkle
2002-07-29T23:59:59.000Z
The fine calibration of the ISO-SWS detectors (Infrared Space Observatory - Short Wavelength Spectrometer) has proven to be a delicate problem. We therefore present a detailed spectroscopic study in the 2.38 -- 12 micron wavelength range of a sample of 16 A0 -- M2 stars used for the calibration of ISO-SWS. By investigating the discrepancies between the ISO-SWS data of these sources, the theoretical predictions of their spectra, the high-resolution FTS-KP (Kitt Peak) spectrum of Alpha Boo and the solar FTS-ATMOS (Atmospheric Trace Molecule Spectroscopy) spectrum, both calibration problems and problems in computing the theoretical models and the synthetic spectra are revealed. The underlying reasons for these problems are sought for and the impact on the further calibration of ISO-SWS and on the theoretical modelling is discussed extensively.
Testing Lack-of-Fit of Generalized Linear Models via Laplace Approximation
Glab, Daniel Laurence
2012-07-16T23:59:59.000Z
, the use of noninformative priors produces a new omnibus lack-of-fit statistic. iv We present a thorough numerical study of the proposed test and the various exist- ing orthogonal series-based tests in the context of the logistic regression model. Simula... . . . . . . . . . . . . . . . 13 1.4.1 The Lack-of-Fit Test . . . . . . . . . . . . . . . . . . . . 14 1.4.2 Smoothing-based Tests of Fit . . . . . . . . . . . . . . . . 15 1.5 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 II TESTS OF FIT FOR LOGISTIC...
Towards a general analysis of LHC data within two-Higgs-doublet models
Celis, Alejandro; Pich, Antonio
2013-01-01T23:59:59.000Z
The data accumulated so far confirm the Higgs-like nature of the new boson discovered at the LHC. The Standard Model Higgs hypothesis is compatible with the collider results and no significant deviations from the Standard Model have been observed neither in the flavour sector nor in electroweak precision observables. We update the LHC and Tevatron constraints on CP-conserving two-Higgs-doublet models without tree-level flavour-changing neutral currents. While the relative sign between the top Yukawa and the gauge coupling of the $126$ GeV Higgs is found be the same as in the SM, at $90%$ CL, there is a sign degeneracy in the determination of its bottom and tau Yukawa couplings. This results in several disjoint allowed regions in the parameter space. We show how generic sum rules governing the scalar couplings determine the properties of the additional Higgs bosons in the different allowed regions. The role of electroweak precision observables, low-energy flavour constraints and LHC searches for additional sca...
Competing Pairing Symmetries in a Generalized Two-Orbital Model for the Pnictide Superconductors
Nicholson, Andrew D [ORNL; Ge, Weihao [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Zhang, Xiaotian [Oak Ridge National Laboratory (ORNL); Riera, J. A. [Universidad Nacional de Rosario; Daghofer, M. [IFW Dresden; Olés, Andrzej M. [Max-Planck-Institut fur Feskorperforschung, Stuttgart, Germany; Martins, G. B. [Oakland University, Rochester, MI; Moreo, Adriana [ORNL; Dagotto, Elbio R [ORNL
2011-01-01T23:59:59.000Z
We introduce and study an extended t-U-J two-orbital model for the pnictides that includes Heisenberg terms deduced from the strong coupling expansion. Including these J terms explicitly allows us to enhance the strength of the %;0 - 0;% spin order which favors the presence of tightly bound pairing states even in the small clusters that are here exactly diagonalized. The A1g and B2g pairing symmetries are found to compete in the realistic spin-ordered and metallic regime. The dynamical pairing susceptibility additionally unveils low-lying B1g states, suggesting that small changes in parameters may render any of the three channels stable.
Goodness-of-Fit Test Issues in Generalized Linear Mixed Models
Chen, Nai-Wei
2012-02-14T23:59:59.000Z
checking of Case 1 for (1)ZSm and (2)cS tran m . . . 58 13 Results of the type I error rate of Sm by using local polynomial smoothed residuals are computed based on the scaled chi-squared distribution cSm...-cluster interaction term of fixed effects between two con- tinuous covariates when the alternative model (4.6) is assumed. . . . 64 17 Results of controlling type I error rate of Sm by using local poly- nomial smoothed residuals are computed based on cSm when...
Truong, Thanh N.
A general methodology for quantum modeling of free-energy profile of reactions in solution methodology for calculating free-energy profile of reaction in solution using quantum mechanical methods screening model GCOSMO was employed in this study, though any continuum model with existing free-energy
Aidun, J.B.; Addessio, F.L.
1995-11-01T23:59:59.000Z
The theoretical basis of the homogenization technique developed by Aboudi is presented and assessed. Given the constitutive relations of the constituents, this technique provides an equivalent, homogeneous, constitutive model of unidirectional, continuous-fiber-reinforced composites. The expressions that comprise the first-order version of the technique are given special attention as this treatment has considerable practical value. Nonlinear elasticity effects are added to it. This extension increases the accuracy of numerical simulations of high strain-rate loadings. It is particularly important for any dynamic loading in which shock waves might be produced, including crash safety, armor, and munitions applications. Examples illustrate that elastic nonlinearity can make substantial contributions at strains of only a few per cent. These contributions are greatest during post-yield inelastic deformation. The micromechanics-based homogenization technique is shown to facilitate use of an efficient approximate treatment of elastic nonlinearity in composites with isotropic matrix materials.
Cryogenic hydrogen circulation system of neutron source
Qiu, Y. N. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 China and University of Chinese Academy of Sciences, Chinese Academy of Sciences, BJ100049 (China); Hu, Z. J.; Wu, J. H.; Li, Q.; Zhang, Y. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 (China); Zhang, P. [School of Energy and Power Engineering, HuaZhong University of Science and Technology, WH430074 (China); Wang, G. P. [Institute of High Energy Physics, Chinese Academy of Sciences, BJ100049 (China)
2014-01-29T23:59:59.000Z
Cold neutron sources of reactors and spallation neutron sources are classic high flux neutron sources in operation all over the world. Cryogenic fluids such as supercritical or supercooled hydrogen are commonly selected as a moderator to absorb the nuclear heating from proton beams. By comparing supercritical hydrogen circulation systems and supercooled hydrogen circulation systems, the merits and drawbacks in both systems are summarized. When supercritical hydrogen circulates as the moderator, severe pressure fluctuations caused by temperature changes will occur. The pressure control system used to balance the system pressure, which consists of a heater as an active controller for thermal compensation and an accumulator as a passive volume controller, is preliminarily studied. The results may provide guidelines for design and operation of other cryogenic hydrogen system for neutron sources under construction.
A General Relativistic Model for Magnetic Monopole-Infused Compact Objects
Zoran Pazameta
2012-01-30T23:59:59.000Z
Emergent concepts from astroparticle physics are incorporated into a classical solution of the Einstein-Maxwell equations for a binary magnetohydrodynamic fluid, in order to describe the final equilibrium state of compact objects infused with magnetic monopoles produced by proton-proton collisions within the intense dipolar magnetic fields generated by these objects during their collapse. It is found that the effective mass of such an object's acquired monopolar magnetic field is three times greater than the mass of its native fluid and monopoles combined, necessitating that the interior matter undergo a transition to a state of negative pressure in order to attain equilibrium. Assuming full symmetry between the electric and magnetic Maxwell equations yields expressions for the monopole charge density and magnetic field by direct analogy with their electrostatic equivalents; inserting these into the Einstein equations then leads to an interior metric which is well-behaved from the origin to the surface, where it matches smoothly to an exterior magnetic Reissner-Nordstr\\"om metric free of any coordinate pathologies. The source fields comprising the model are all described by simple, well-behaved polynomial functions of the radial coordinate, and are combined with straightforward regularity conditions to yield expressions delimiting several fundamental physical parameters pertaining to this hypothetical astrophysical object.
Greenland's Island Rule and the Arctic Ocean circulation by Terrence M. Joyce1,2
Joyce, Terrence M.
Greenland's Island Rule and the Arctic Ocean circulation by Terrence M. Joyce1,2 and Andrey made for the flow around Greenland. Godfrey's theory has been extended to permit inclusion of Bering Archipelago in the modeled flow west of Greenland. In both models, the forcing has been applied in a quasi
Arzel, Olivier
with a circulation in the opposite sense. Clearly, it is the dif- ferent nature of the heat and freshwater coupling April 2010) ABSTRACT Recent results based on models using prescribed surface wind stress forcing have) into the Atlantic basin is a good indicator of the multiple-equilibria regime. By means of a coupled climate model
Circulating Fluidized Bed Boilers Market Size | OpenEI Community
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 You are beingZealand JumpConceptual Model, click here.TelluricPower InternationalChuichu,Cima NanoTechCinergyforCirculating
Ribes, AurÃ©lien
analyzing the global thermal properties of atmosphereÂocean coupled general circulation models (AOGCMs perturbation, some EBMs assume that the thermal energy balance of the climate system is only expressedTransient Climate Response in a Two-Layer Energy-Balance Model. Part I: Analytical Solution
M. Wakamatsu; H. Tsujimoto
2005-03-29T23:59:59.000Z
The theoretical predictions are given for the forward limit of the unpolarized spin-flip isovector generalized parton distribution function $(E^u - E^d)(x, \\xi, t)$ within the framework of the chiral quark soliton model, with full inclusion of the polarization of Dirac sea quarks. We observe that $[(H^u - H^d) + (E^u - E^d)](x,0,0)$ has a sharp peak around $x=0$, which we interpret as a signal of the importance of the pionic $q \\bar{q}$ excitation with large spatial extension in the transverse direction. Another interesting indication given by the predicted distribution in combination with Ji's angular momentum sum rule is that the $\\bar{d}$-quark carries more angular momentum than the $\\bar{u}$-quark in the proton, which may have some relation with the physics of the violation of the Gottfried sum rule.
DOPPLER SIGNATURES OF THE ATMOSPHERIC CIRCULATION ON HOT JUPITERS
Showman, Adam P.; Lewis, Nikole K. [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, 1629 University Boulevard, Tucson, AZ 85721 (United States)] [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, 1629 University Boulevard, Tucson, AZ 85721 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)] [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Shabram, Megan, E-mail: showman@lpl.arizona.edu [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States)] [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States)
2013-01-01T23:59:59.000Z
The meteorology of hot Jupiters has been characterized primarily with thermal measurements, but recent observations suggest the possibility of directly detecting the winds by observing the Doppler shift of spectral lines seen during transit. Motivated by these observations, we show how Doppler measurements can place powerful constraints on the meteorology. We show that the atmospheric circulation-and Doppler signature-of hot Jupiters splits into two regimes. Under weak stellar insolation, the day-night thermal forcing generates fast zonal jet streams from the interaction of atmospheric waves with the mean flow. In this regime, air along the terminator (as seen during transit) flows toward Earth in some regions and away from Earth in others, leading to a Doppler signature exhibiting superposed blueshifted and redshifted components. Under intense stellar insolation, however, the strong thermal forcing damps these planetary-scale waves, inhibiting their ability to generate jets. Strong frictional drag likewise damps these waves and inhibits jet formation. As a result, this second regime exhibits a circulation dominated by high-altitude, day-to-night airflow, leading to a predominantly blueshifted Doppler signature during transit. We present state-of-the-art circulation models including non-gray radiative transfer to quantify this regime shift and the resulting Doppler signatures; these models suggest that cool planets like GJ 436b lie in the first regime, HD 189733b is transitional, while planets hotter than HD 209458b lie in the second regime. Moreover, we show how the amplitude of the Doppler shifts constrains the strength of frictional drag in the upper atmospheres of hot Jupiters. If due to winds, the {approx}2 km s{sup -1} blueshift inferred on HD 209458b may require drag time constants as short as 10{sup 4}-10{sup 6} s, possibly the result of Lorentz-force braking on this planet's hot dayside.
Holanda, R.F.L.; Lima, J.A.S. [Departamento de Astronomia (IAGUSP), Universidade de São Paulo, Rua do Matão 1226, 05508-900, São Paulo, SP (Brazil); Cunha, J.V. [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia 166, 09210-170, Santo André, SP (Brazil); Marassi, L., E-mail: holanda@astro.iag.usp.br, E-mail: jvcunha@ufpa.br, E-mail: luciomarassi@ect.ufrn.br, E-mail: limajas@astro.iag.usp.br [Escola de Ciência e Tecnologia, UFRN, 59072-970, Natal, RN (Brazil)
2012-02-01T23:59:59.000Z
In accelerating dark energy models, the estimates of the Hubble constant, H{sub 0}, from Sunyaev-Zel'dovich effect (SZE) and X-ray surface brightness of galaxy clusters may depend on the matter content (?{sub M}), the curvature (?{sub K}) and the equation of state parameter (?). In this article, by using a sample of 25 angular diameter distances of galaxy clusters described by the elliptical ? model obtained through the SZE/X-ray technique, we constrain H{sub 0} in the framework of a general ?CDM model (arbitrary curvature) and a flat XCDM model with a constant equation of state parameter ? = p{sub x}/?{sub x}. In order to avoid the use of priors in the cosmological parameters, we apply a joint analysis involving the baryon acoustic oscillations (BAO) and the CMB Shift Parameter signature. By taking into account the statistical and systematic errors of the SZE/X-ray technique we obtain for nonflat ?CDM model H{sub 0} = 74{sup +5.0}{sub ?4.0} km s{sup ?1} Mpc{sup ?1}(1?) whereas for a flat universe with constant equation of state parameter we find H{sub 0} = 72{sup +5.5}{sub ?4.0} km s{sup ?1} Mpc{sup ?1}(1?). By assuming that galaxy clusters are described by a spherical ? model these results change to H{sub 0} = 62{sup +8.0}{sub ?7.0} and H{sub 0} = 59{sup +9.0}{sub ?6.0} km s{sup ?1} Mpc{sup ?1}(1?), respectively. The results from elliptical description are in good agreement with independent studies from the Hubble Space Telescope key project and recent estimates based on the Wilkinson Microwave Anisotropy Probe, thereby suggesting that the combination of these three independent phenomena provides an interesting method to constrain the Hubble constant. As an extra bonus, the adoption of the elliptical description is revealed to be a quite realistic assumption. Finally, by comparing these results with a recent determination for a flat ?CDM model using only the SZE/X-ray technique and BAO, we see that the geometry has a very weak influence on H{sub 0} estimates for this combination of data.
T. P. Shestakova
2013-03-06T23:59:59.000Z
Among theoretical issues in General Relativity the problem of constructing its Hamiltonian formulation is still of interest. The most of attempts to quantize Gravity are based upon Dirac generalization of Hamiltonian dynamics for system with constraints. At the same time there exists another way to formulate Hamiltonian dynamics for constrained systems guided by the idea of extended phase space. We have already considered some features of this approach in the previous MG12 Meeting by the example of a simple isotropic model. Now we apply the approach to a generalized spherically symmetric model which imitates the structure of General Relativity much better. In particular, making use of a global BRST symmetry and the Noether theorem, we construct the BRST charge that generates correct gauge transformations for all gravitational degrees of freedom.
Cluster Dynamics in a Circulating Fluidized Bed
Guenther, C.P.; Breault, R.W.
2006-11-01T23:59:59.000Z
A common hydrodynamic feature in industrial scale circulating fluidized beds is the presence of clusters. The continuous formation and destruction of clusters strongly influences particle hold-up, pressure drop, heat transfer at the wall, and mixing. In this paper fiber optic data is analyzed using discrete wavelet analysis to characterize the dynamic behavior of clusters. Five radial positions at three different axial locations under five different operating were analyzed using discrete wavelets. Results are summarized with respect to cluster size and frequency.
Reducing mode circulating fluid bed combustion
Lin, Yung-Yi (Katy, TX); Sadhukhan, Pasupati (Katy, TX); Fraley, Lowell D. (Sugarland, TX); Hsiao, Keh-Hsien (Houston, TX)
1986-01-01T23:59:59.000Z
A method for combustion of sulfur-containing fuel in a circulating fluid bed combustion system wherein the fuel is burned in a primary combustion zone under reducing conditions and sulfur captured as alkaline sulfide. The reducing gas formed is oxidized to combustion gas which is then separated from solids containing alkaline sulfide. The separated solids are then oxidized and recycled to the primary combustion zone.
NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project
Not Available
1992-02-01T23:59:59.000Z
The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)
Continuous Circulation System: a new enabling technology
Kenawy, Walid F.
2002-01-01T23:59:59.000Z
time-consuming hole problems trom occurring. It is worth mentioning that pipe rotation is as important for prevention of settling of cuttings as sufficient circulation, as the rotation of the drill pipe acts to agitate any solids settled back... rotation enhances the hole cleaning by the agitation effect of rotation and vibration . ' ' Since one of the main advantages of the CCS is to keep the cuttings moving towards the surface, then the idea of modifying the CCS to allow for drillstring...
The effects of small perturbations in climate models
Bell, Robert Eugene
1991-01-01T23:59:59.000Z
An energy balance model . II. 2 Equilibrium statistics 5 12 III A GENERAL CIRCULATION MODEL . . III. 1 Terra Blimda . III. 2 Equilibrium statistics 15 18 IV THE EFFECTS OF SMALL PERTURBATIONS . . 21 IV. 1 Response to a, Dirac delta, function IV. 2... standard deviations from the mean. , Relaxation time for different modes as a function of Legendre index n (North and Cahalan, 1981). 13 Illustration of a, rhomboidal truncation at degree 5 (R5). 17 The global mean surface temperature of Terra Blanda...
On the non-linear response of the ocean thermohaline circulation to global deforestation
Renssen, Hans
On the non-linear response of the ocean thermohaline circulation to global deforestation H. Renssen-dimensional coupled atmosphere-sea-ice- ocean-vegetation model to study the transient effect of global deforestation deforestation, Geophys. Res. Lett., 30(2), 1061, doi:10.1029/ 2002GL016155, 2003. 1. Introduction [2] It has
Eocene circulation of the Southern Ocean: Was Antarctica kept warm by subtropical waters?
Döös, Kristofer
climate model simulations. We find that the EAC did not penetrate to high latitudes and ocean heatEocene circulation of the Southern Ocean: Was Antarctica kept warm by subtropical waters? Matthew suddenly grew and ocean productivity patterns changed. Previous studies conjectured that poleward
Manga, Michael
on groundwater flow depths within the basin. An analytical model based on these constraints indicates@berkeley.edu. Tel: +1 510 642 2288. Fax: +1 510 643 9980. Geofluids (2009) 9, 195Â207 INTRODUCTION Groundwater and groundwater circulation MARIA BRUMM, CHI-YUEN WANG AND MICHAEL MANGA Earth and Planetary Science, University
Generalized interaction in multigravity
Duplij, Steven
2013-01-01T23:59:59.000Z
A general approach to description of multigravity models in D-dimensional space-time is presented. Different possibilities of generalization of the invariant volume are given. Then a most general form of the interaction potential is constructed, which for bigravity coincides with the Pauli-Fierz model. A thorough analysis of the model along the 3+1 expansion formalism is done. It is shown that the absence of ghosts the considered bigravity model is equivalent in the weak field limit to the massive gravity (the Pauli-Fierz model). Thus, on the concrete example it is shown, that the interaction between metrics leads to nonvanishing mass of graviton.
THREE-DIMENSIONAL ATMOSPHERIC CIRCULATION OF HOT JUPITERS ON HIGHLY ECCENTRIC ORBITS
Kataria, T.; Showman, A. P.; Lewis, N. K. [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States)] [Department of Planetary Sciences and Lunar and Planetary Laboratory, The University of Arizona, Tucson, AZ 85721 (United States); Fortney, J. J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)] [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Marley, M. S.; Freedman, R. S., E-mail: tkataria@lpl.arizona.edu [NASA Ames Research Center 245-3, Moffett Field, CA 94035 (United States)
2013-04-10T23:59:59.000Z
Of the over 800 exoplanets detected to date, over half are on non-circular orbits, with eccentricities as high as 0.93. Such orbits lead to time-variable stellar heating, which has major implications for the planet's atmospheric dynamical regime. However, little is known about the fundamental dynamical regime of such planetary atmospheres, and how it may influence the observations of these planets. Therefore, we present a systematic study of hot Jupiters on highly eccentric orbits using the SPARC/MITgcm, a model which couples a three-dimensional general circulation model (the MITgcm) with a plane-parallel, two-stream, non-gray radiative transfer model. In our study, we vary the eccentricity and orbit-average stellar flux over a wide range. We demonstrate that the eccentric hot Jupiter regime is qualitatively similar to that of planets on circular orbits; the planets possess a superrotating equatorial jet and exhibit large day-night temperature variations. As in Showman and Polvani, we show that the day-night heating variations induce momentum fluxes equatorward to maintain the superrotating jet throughout its orbit. We find that as the eccentricity and/or stellar flux is increased (corresponding to shorter orbital periods), the superrotating jet strengthens and narrows, due to a smaller Rossby deformation radius. For a select number of model integrations, we generate full-orbit light curves and find that the timing of transit and secondary eclipse viewed from Earth with respect to periapse and apoapse can greatly affect what we see in infrared (IR) light curves; the peak in IR flux can lead or lag secondary eclipse depending on the geometry. For those planets that have large temperature differences from dayside to nightside and rapid rotation rates, we find that the light curves can exhibit 'ringing' as the planet's hottest region rotates in and out of view from Earth. These results can be used to explain future observations of eccentric transiting exoplanets.
Wind induced circulation on the outer continental shelf of Texas, spring 1982
Beard, Daniel Walker
1984-01-01T23:59:59.000Z
in the record is offshore, to the southeast. On the 29th of March, in the wake of strong northeast winds, the current shifted to the west. In general, the westward direction was maintained throughout the deployment period. However, there was one occurrence... WIND INDUCED CIRCULATION ON THE OUTER CONTINENTAL SHELF OF TEXAS, SPRING 1982 A Thesis by DANIEL WALKER BEARD Submitted to the Graduate College of Texas AE M University in partial fulfillment of the requirements for the degree of MASTER...
Rhode Island, University of
Impact of a Warm Ocean Eddy's Circulation on Hurricane-Induced Sea Surface Cooling with Implications for Hurricane Intensity RICHARD M. YABLONSKY AND ISAAC GINIS Graduate School of Oceanography) ABSTRACT Upper oceanic heat content (OHC) in advance of a hurricane is generally superior to prestorm sea
Nucla circulating atmospheric fluidized bed demonstration project
Not Available
1991-01-31T23:59:59.000Z
During the fourth quarter of 1990, steady-state performance testing at the Nucla Circulating Fluidized Bed (CFB) resumed under sponsorship of the US Department of Energy. Co-sponsorship of the Demonstration Test Program by the Electric Power Research Institute (EPRI) was completed on June 15, 1990. From October through December, 1990, Colorado-Ute Electric Association (CUEA) completed a total of 23 steady-state performance tests, 4 dynamic tests, and set operating records during November and December as the result of improved unit operating reliability. Highlight events and achievements during this period of operation are presented.
NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project
Not Available
1991-01-01T23:59:59.000Z
This Annual Report on Colorado-Ute Electric Association's NUCLA Circulating Fluidized Bed (CFB) Demonstration Program covers the period from February 1987 through December 1988. The outline for presentation in this report includes a summary of unit operations along with individual sections covering progress in study plan areas that commenced during this reporting period. These include cold-mode shakedown and calibration, plant commercial performance statistics, unit start-up (cold), coal and limestone preparation and handling, ash handling system performance and operating experience, tubular air heater, baghouse operation and performance, materials monitoring, and reliability monitoring. During this reporting period, the coal-mode shakedown and calibration plan was completed. (VC)
Carderock Circulating Water Channel | Open Energy Information
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 You are being directedAnnualProperty EditCalifornia:Power LPInformation 8thCalwind IICaneyNW1Circulating Water Channel
Prospects for the Detection of the Deep Solar Meridional Circulation
D. C. Braun; A. C. Birch
2008-10-01T23:59:59.000Z
We perform helioseismic holography to assess the noise in p-mode travel-time shifts which would form the basis of inferences of large-scale flows throughout the solar convection zone. We also derive the expected travel times from a parameterized return (equatorward) flow component of the meridional circulation at the base of the convection zone from forward models under the assumption of the ray and Born approximations. From estimates of the signal-to-noise ratio for measurements focused near the base of the convection zone, we conclude that the helioseismic detection of the deep meridional flow including the return component may not be possible using data spanning an interval less than a solar cycle.
Nishi, Sakine
2015-01-01T23:59:59.000Z
The galilean genesis scenario is an alternative to inflation in which the universe starts expanding from Minkowski in the asymptotic past by violating the null energy condition stably. Several concrete models of galilean genesis have been constructed so far within the context of galileon-type scalar-field theories. We give a generic, unified description of the galilean genesis scenario in terms of the Horndeski theory, i.e., the most general scalar-tensor theory with second-order field equations. In doing so we generalize the previous models to have a new parameter (denoted by {\\alpha}) which results in controlling the evolution of the Hubble rate. The background dynamics is investigated to show that the generalized galilean genesis solution is an attractor, similarly to the original model. We also study the nature of primordial perturbations in the generalized galilean genesis scenario. In all the models described by our generalized genesis Lagrangian, amplification of tensor perturbations does not occur as ...
Fluid Circulation and Heat Extraction from Engineered Geothermal...
A large amount of fluid circulation and heat extraction (i.e., thermal power production) research and testing has been conducted on engineered geothermal reservoirs in the...
altered circulating levels: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
decadal oscillations of the Atlantic meridional overturning circulation in a cold climate oscillations and North Atlantic Oscil- lation (NAO)-like sea level pressure...
Progress in The Lost Circulation Technology Development Program
Glowka, D.A.; Schafer, D.M.; Loeppke, G.E.; Wright, E.K.
1991-01-01T23:59:59.000Z
Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50{percent} through the development of mitigation and characterization technology. This paper describes the technical progress made in this program during the period April, 1990--March, 1991. 4 refs., 15 figs., 1 tab.
Van Gorder, Robert A., E-mail: rav@knights.ucf.edu [Department of Mathematics, University of Central Florida, Orlando, Florida 32816-1364 (United States)
2014-11-15T23:59:59.000Z
In R. A. Van Gorder, “General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation,” Phys. Fluids 26, 065105 (2014) I discussed properties of generalized vortex filaments exhibiting purely rotational motion under the low-temperature Svistunov model of the local induction approximation. Such solutions are stationary in terms of translational motion. In the Comment [N. Hietala, “Comment on ‘General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation’ [Phys. Fluids 26, 065105 (2014)],” Phys. Fluids 26, 119101 (2014)], the author criticizes my paper for not including translational motion (although it was clearly stated that the filament motion was assumed rotational). As it turns out, if one is interested in studying the geometric structure of solutions (which was the point of my paper), one obtains the needed qualitative results on the structure of such solutions by studying the purely rotational case. Nevertheless, in this Response I shall discuss the vortex filaments that have both rotational and translational motions. I then briefly discuss why one might want to study such generalized rotating filament solutions, in contrast to simple the standard helical or planar examples (which are really special cases). I also discuss how one can study the time evolution of filaments which exhibit more complicated dynamics than pure translation and rotation. Doing this, one can study non-stationary solutions which initially appear purely rotational and gradually display other dynamics as the filaments evolve.
Do Coupled Climate Models Correctly SImulate the Upward Branch of the Deept Ocean Global Conveyor?
Sarmiento, Jorge L; Downes, Stephanie; Bianchi, Daniele
2013-01-17T23:59:59.000Z
The large-scale meridional overturning circulation (MOC) connects the deep ocean, a major reservoir of carbon, to the other components of the climate system and must therefore be accurately represented in Earth System Models. Our project aims to address the specific question of the pathways and mechanisms controlling the upwelling branch of the MOC, a subject of significant disagreement between models and observational syntheses, and among general circulation models. Observations of these pathways are limited, particularly in regions of complex hydrography such as the Southern Ocean. As such, we rely on models to examine theories of the overturning circulation, both physically and biogeochemically. This grant focused on a particular aspect of the meridional overturning circulation (MOC) where there is currently significant disagreement between models and observationally based analyses of the MOC, and amongst general circulation models. In particular, the research focused on addressing the following questions: 1. Where does the deep water that sinks in the polar regions rise to the surface? 2. What processes are responsible for this rise? 3. Do state-of-the-art coupled GCMs capture these processes? Our research had three key components: observational synthesis, model development and model analysis. In this final report we outline the key results from these areas of research for the 2007 to 2012 grant period. The research described here was carried out primarily by graduate student, Daniele Bianchi (now a Postdoc at McGill University, Canada), and Postdoc Stephanie Downes (now a Research Fellow at The Australian national University, Australia). Additional support was provided for programmers Jennifer Simeon as well as Rick Slater.
Primary cementing across massive lost circulation zones
Turki, W.H.; Mackay, A.S.
1983-03-01T23:59:59.000Z
As a result of severe lost circulation problems in some wells in the Ghawar and Abqaiq Fields, Aramco has been unable to cover the Umm Er-Radhuma (Paleocene) and Wasia (Cretaceous) aquifers with cement. This has necessitated setting an extended liner opposite the Wasia aquifer, to ensure that there are two casing strings and a cement sheath across the aquifer, resulting in increased casing cost and reduced well productivity. This paper describes the results of field trial tests performed, along with conclusions and recommendations aimed at solving this problem. Field methods employed include light weight extended cements, ultra-light cement slurries weighing as little as 55 lbm/ft/sup 3/ (pcf), using ceramic hollow spheres, glass bubbles and foam, plus hydrostatic cementing, and mechanical devices. Finally, methods of job evaluation are discussed. These include temperature surveys, bond logs, radioactive tracers, and a new cement volume log.
Thermodynamics of atmospheric circulation on hot Jupiters
J. Goodman
2008-10-07T23:59:59.000Z
Atmospheric circulation on tidally-locked exoplanets is driven by the absorption and reradiation of heat from the host star. They are natural heat engines, converting heat into mechanical energy. A steady state is possible only if there is a mechanism to dissipate mechanical energy, or if the redistribution of heat is so effective that the Carnot efficiency is driven to zero. Simulations based on primitive, equivalent-barotropic, or shallow-water equations without explicit provision for dissipation of kinetic energy and for recovery of that energy as heat, violate energy conservation. More seriously perhaps, neglect of physical sources of drag may overestimate wind speeds and rates of advection of heat from the day to the night side.
Nucla circulating atmospheric fluidized bed demonstration project
Keith, Raymond E.
1991-10-01T23:59:59.000Z
Colorado-Ute Electric Association began a study to evaluate options for upgrading and extending the life of its Nucla power station in 1982. Located in southwestern Colorado near the town of Nucla, this station was commissioned in 1959 with a local bituminous coal as its design fuel for three identical stoker-fired units, each rated at 12.6 MW(e). Poor station efficiency, high fuel costs, and spiraling boiler maintenance costs forced the Nucla Station into low priority in the CUEA dispatch order as early as 1981. Among the options CUEA considered was to serve as a host utility to demonstrate Atmospheric Fluidized Bed Combustion (AFBC) technology. The anticipated environmental benefits and apparent attractive economics of a circulating AFBC led to Colorado-Ute's decision to proceed with the design and construction of a demonstration project in 1984 at the Nucla facility.
Alvarez, Pedro J.
and Environmental Engineering, Rice University, MS-317, 6100 Main St., Houston, TX 77005, USA a r t i c l e i n f o a b s t r a c t Article history: Received 30 October 2009 Received in revised form 26 January 2010 generalizations about the level of impact of specific fuel alcohols on benzene plume dynamics. Â© 2010 Elsevier B
Uncertainty quantification for large-scale ocean circulation predictions.
Safta, Cosmin; Debusschere, Bert J.; Najm, Habib N.; Sargsyan, Khachik
2010-09-01T23:59:59.000Z
Uncertainty quantificatio in climate models is challenged by the sparsity of the available climate data due to the high computational cost of the model runs. Another feature that prevents classical uncertainty analyses from being easily applicable is the bifurcative behavior in the climate data with respect to certain parameters. A typical example is the Meridional Overturning Circulation in the Atlantic Ocean. The maximum overturning stream function exhibits discontinuity across a curve in the space of two uncertain parameters, namely climate sensitivity and CO{sub 2} forcing. We develop a methodology that performs uncertainty quantificatio in the presence of limited data that have discontinuous character. Our approach is two-fold. First we detect the discontinuity location with a Bayesian inference, thus obtaining a probabilistic representation of the discontinuity curve location in presence of arbitrarily distributed input parameter values. Furthermore, we developed a spectral approach that relies on Polynomial Chaos (PC) expansions on each sides of the discontinuity curve leading to an averaged-PC representation of the forward model that allows efficient uncertainty quantification and propagation. The methodology is tested on synthetic examples of discontinuous data with adjustable sharpness and structure.
Scarlat, Raluca Olga
2012-01-01T23:59:59.000Z
natural circulation solar water heater. Energy Conversionas water circulation in solar water heaters 60 , and passivewater circulation in solar water heaters 60 , and passive
Rahul Ghosh; Surajit Chattopadhyay; Ujjal Debnath
2011-10-22T23:59:59.000Z
This work is motivated by the work of Kim et al (2008), which considered the equation of state parameter for the new agegraphic dark energy based on generalized uncertainty principle coexisting with dark matter without interaction. In this work, we have considered the same dark energy inter- acting with dark matter in emergent, intermediate and logamediate scenarios of the universe. Also, we have investigated the statefinder, kerk and lerk parameters in all three scenarios under this inter- action. The energy density and pressure for the new agegraphic dark energy based on generalized uncertainty principle have been calculated and their behaviors have been investigated. The evolu- tion of the equation of state parameter has been analyzed in the interacting and non-interacting situations in all the three scenarios. The graphical analysis shows that the dark energy behaves like quintessence era for logamediate expansion and phantom era for emergent and intermediate expansions of the universe.
Johansson, L.; Magnuson, B. (ABB Components AB, Ludvika (Sweden)); Riffon, P. (Hydro-Quebec, Montreal, Quebec (Canada))
1993-07-01T23:59:59.000Z
The loading capability of a 500 kV HVDC transformer bushing is calculated with some unusual conditions: the internal oil circulation in the bushing is blocked at the flange level and the ambient air temperature is raised to 60 C. The theoretical model was verified with a full-scale heat run test on a 7.8 m long bushing. A 220 m[sup 3] insulated test chamber was required to enclose the test set-up.
Gurgel, Angelo C.
We develop a forward-looking version of the MIT Emissions Prediction and Policy Analysis (EPPA) model, and apply it to examine the economic implications of proposals in the U.S. Congress to limit greenhouse gas (GHG) ...
Gilman, Lindsey Anne
2014-01-01T23:59:59.000Z
Advanced modeling capabilities were developed for application to subcooled flow boiling through this work. The target was to introduce, and demonstrate, all necessary mechanisms required to accurately predict the temperature ...
On the World-wide Circulation of the Deeper Waters of the World Ocean
Reid, Joseph L
2009-01-01T23:59:59.000Z
circulation of the Pacific Ocean: Flow patterns, tracers,in preparing the figures. Fig. 1 Pacific Ocean winds Fig.2 Pacific Ocean circulation Fig. 4 Pacific Ocean potential
Newton, James Edward
1982-01-01T23:59:59.000Z
are reported for FeP where P = porphinato(2-) ~ (NH2)4 , (NHCH2)4 , (N4C2H10) , (N4CBH6) and for Fe(02)PL where P = porphi nato(2-), (NH2)4 , (N4C2H6) and L = imidazole, NH3. The MO calculations indicate that (N4C2H6) is a better model for the porphyri n... ring in metal-dioxygen porphyrin complexes than the model (NH ) . This model was employed in generalized molecular orbital-confi guration interaction calculations of Fe(02)P(NH3), Co(02)P(NH3), and Mn(02)P where P = (N4C2H6) The ozone...
Herrera, Ramón; Olivares, Marco
2015-01-01T23:59:59.000Z
A warm inflationary Universe in the Randall-Sundrum II model during intermediate inflation is studied. For this purpose, we consider a general form for the dissipative coefficient $\\Gamma(T,\\phi)=C_{\\phi}\\,\\frac{T^{m}}{\\phi^{m-1}}$, and also analyze this inflationary model in the weak and strong dissipative regimes. We study the evolution of the Universe under the slow-roll approximation and find solutions to the full effective Friedmann equation in the brane-world framework. In order to constrain the parameters in our model, we consider the recent data from the BICEP2-Planck 2015 data together with the necessary condition for warm inflation $T>H$, and also the condition from the weak (or strong) dissipative regime.
Ramón Herrera; Nelson Videla; Marco Olivares
2015-04-28T23:59:59.000Z
A warm inflationary Universe in the Randall-Sundrum II model during intermediate inflation is studied. For this purpose, we consider a general form for the dissipative coefficient $\\Gamma(T,\\phi)=C_{\\phi}\\,\\frac{T^{m}}{\\phi^{m-1}}$, and also analyze this inflationary model in the weak and strong dissipative regimes. We study the evolution of the Universe under the slow-roll approximation and find solutions to the full effective Friedmann equation in the brane-world framework. In order to constrain the parameters in our model, we consider the recent data from the BICEP2-Planck 2015 data together with the necessary condition for warm inflation $T>H$, and also the condition from the weak (or strong) dissipative regime.
The Role of Eddy-Tansport in the Thermohaline Circulation
Dr. Paola Cessi
2011-11-17T23:59:59.000Z
Several research themes were developed during the course of this project. (1) Low-frequency oceanic varibility; (2) The role of eddies in the Antarctic Circumpolar Current (ACC) region; (3) Deep stratification and the overturning circulation. The key findings were as follows: (1) The stratification below the main thermocline (at about 500m) is determined in the circumpolar region and then communicated to the enclosed portions of the oceans through the overturning circulation. (2) An Atlantic pole-to-pole overturning circulation can be maintained with very small interior mixing as long as surface buoyancy values are shared between the northern North Atlantic and the ACC region.
Sony, Priya
2009-01-01T23:59:59.000Z
Pariser-Parr-Pople (P-P-P) model Hamiltonian has been used extensively over the years to perform calculations of electronic structure and optical properties of $\\pi$-conjugated systems successfully. In spite of tremendous successes of \\emph{ab initio} theory of electronic structure of large systems, the P-P-P model continues to be a popular one because of a recent resurgence in interest in the physics of $\\pi$-conjugated polymers, fullerenes and other carbon based materials. In this paper, we describe a Fortran 90 computer program developed by us, which uses P-P-P model Hamiltonian to not only solve Hartree-Fock (HF) equation for closed- and open-shell systems, but also for performing correlation calculations at the level of single configuration interactions (SCI) for molecular systems. Moreover, the code is capable of computing linear optical absorption spectrum at various levels, such as, tight binding (TB) Hueckel model, HF, SCI, and also of calculating the band structure using the Hueckel model. The code ...
Optimization Under Generalized Uncertainty
Lodwick, Weldon
11 Optimization Under Generalized Uncertainty Optimization Modeling Math 4794/5794: Spring 2013 Weldon A. Lodwick Weldon.Lodwick@ucdenver.edu 2/14/2013 Optimization Modeling - Spring 2013 #12 in the context of optimization problems. The theoretical frame-work for these notes is interval analysis. From
Heermann, Dieter W.
parametrization for Bisphenol-A-Polycarbonate Klaus M. Zimmer, Andreas Linke and Dieter W. Heermann Institut fur of the monomer units. We apply the model to the special case of Bisphenol-A-Polycarbonate (BPA- PC) and present properties of polycarbonate systems. We will also present properties and e ciency considerations
Casey, James Elmer
1973-01-01T23:59:59.000Z
. Hypothetical Factor-Pactor Model indicating profit maximizing conditions with limited capital and with a variab1e input limitation 24 P2 units, then other inputs would be added until their marginal value poduct was equal to their price. This would...
Noone, David
coordinates. In this depiction, poleward transport of air and water vapor is non-diffusive, in a way for an open distillation. Model experiments that simulate a wide range of circulation strengths show to the polar region exceeds the rate at which surface sources replenish the poleward moving air stream. Across
McGillicuddy Jr., Dennis J.
Near-bottom circulation and dispersion of sediment containing Alexandrium fundyense cysts evaluates model near-bottom flow during storms, when sediment resuspension and redistribution are most a r t i c l e i n f o Available online 16 December 2013 Keywords: Sediment connectivity Near
Objective Our goal is to develop a modeling formalism for representing state and change of state. Approach We represent cyber systems as discrete mathematical objects interacting across hierarchically
Gas phase hydrodynamics inside a circulating fluidized bed
Moran, James C. (James Christopher)
2001-01-01T23:59:59.000Z
Circulating Fluidized Beds (CFB's) offer many advantages over traditional pulverized coal burners in the power generation industry. They operate at lower temperatures, have better environmental emissions and better fuel ...
atlantic thermohaline circulation: Topics by E-print Network
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Pacific at least as far as the paleolocation of Fe-Mn Crust CLD01 (5N Thomas, Debbie 235 Thermohaline circulation induced by bottom friction in sloping-boundary basins...
Circulating heat exchangers for oscillating wave engines and refrigerators
Swift, Gregory W.; Backhaus, Scott N.
2003-10-28T23:59:59.000Z
An oscillating-wave engine or refrigerator having a regenerator or a stack in which oscillating flow of a working gas occurs in a direction defined by an axis of a trunk of the engine or refrigerator, incorporates an improved heat exchanger. First and second connections branch from the trunk at locations along the axis in selected proximity to one end of the regenerator or stack, where the trunk extends in two directions from the locations of the connections. A circulating heat exchanger loop is connected to the first and second connections. At least one fluidic diode within the circulating heat exchanger loop produces a superimposed steady flow component and oscillating flow component of the working gas within the circulating heat exchanger loop. A local process fluid is in thermal contact with an outside portion of the circulating heat exchanger loop.
Circulation of autonomous agents in production and service networks
Floreano, Dario
Circulation of autonomous agents in production and service networks Olivier Gallay Ã, Max author. Tel.: +41216935817; fax: +41216933891. E-mail address: olivier.gallay@epfl.ch (O. Gallay). Int. J
Improving Heating System Operations Using Water Re-Circulation
Li, F.; Han, J.
2006-01-01T23:59:59.000Z
In order to solve the imbalance problem of a heating system, brought about by consumer demand and regulation, and save the electricity energy consumed by a circulation pump, a water mixing and pressure difference control heating system is proposed...
The decadal mean ocean circulation and Sverdrup balance
Wunsch, Carl
Elementary Sverdrup balance is tested in the context of the time-average of a 16-year duration time-varying ocean circulation estimate employing the great majority of global-scale data available between 1992 and 2007. The ...
Colaiori, Francesca; Cuskley, Christine F; Loreto, Vittorio; Pugliese, Martina; Tria, Francesca
2014-01-01T23:59:59.000Z
Empirical evidence shows that the rate of irregular usage of English verbs exhibits discontinuity as a function of their frequency: the most frequent verbs tend to be totally irregular. We aim to qualitatively understand the origin of this feature by studying simple agent--based models of language dynamics, where each agent adopts an inflectional state for a verb and may change it upon interaction with other agents. At the same time, agents are replaced at some rate by new agents adopting the regular form. In models with only two inflectional states (regular and irregular), we observe that either all verbs regularize irrespective of their frequency, or a continuous transition occurs between a low frequency state where the lemma becomes fully regular, and a high frequency one where both forms coexist. Introducing a third (mixed) state, wherein agents may use either form, we find that a third, qualitatively different behavior may emerge, namely, a discontinuous transition in frequency. We introduce and solve an...
Yang, Zhaoqing; Khangaonkar, Tarang
2010-11-19T23:59:59.000Z
Water circulation in Puget Sound, a large complex estuary system in the Pacific Northwest coastal ocean of the United States, is governed by multiple spatially and temporally varying forcings from tides, atmosphere (wind, heating/cooling, precipitation/evaporation, pressure), and river inflows. In addition, the hydrodynamic response is affected strongly by geomorphic features, such as fjord-like bathymetry and complex shoreline features, resulting in many distinguishing characteristics in its main and sub-basins. To better understand the details of circulation features in Puget Sound and to assist with proposed nearshore restoration actions for improving water quality and the ecological health of Puget Sound, a high-resolution (around 50 m in estuaries and tide flats) hydrodynamic model for the entire Puget Sound was needed. Here, a threedimensional circulation model of Puget Sound using an unstructured-grid finite volume coastal ocean model is presented. The model was constructed with sufficient resolution in the nearshore region to address the complex coastline, multi-tidal channels, and tide flats. Model open boundaries were extended to the entrance of the Strait of Juan de Fuca and the northern end of the Strait of Georgia to account for the influences of ocean water intrusion from the Strait of Juan de Fuca and the Fraser River plume from the Strait of Georgia, respectively. Comparisons of model results, observed data, and associated error statistics for tidal elevation, velocity, temperature, and salinity indicate that the model is capable of simulating the general circulation patterns on the scale of a large estuarine system as well as detailed hydrodynamics in the nearshore tide flats. Tidal characteristics, temperature/salinity stratification, mean circulation, and river plumes in estuaries with tide flats are discussed.
On the circulation and stratification of the Weddell Gyre
Orsi, Alejandro H.
1990-01-01T23:59:59.000Z
ON THE CIRCULATION AND STRATIFICATION OF THE WEDDELL GYRE A Thesis by ALEIANDRO H. ORSI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... August 1990 Major Subject: Oceanography ON THE CIRCULATION AND STRATIFICATION OF THE WEDDELL GYRE A Thesis by ALE JANDRO H. ORSI Approved as to style and content by: Worth D. No in, Jr. (Chair of Committee) Thomas Whitworth III (Member...
Kick circulation analysis for extended reach and horizontal wells
Long, Maximilian Mark
2005-02-17T23:59:59.000Z
KICK CIRCULATION ANALYSIS FOR EXTENDED-REACH AND HORIZONTAL WELLS A Thesis by MAXIMILIAN M. LONG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 2004 Major Subject: Petroleum Engineering KICK CIRCULATION ANALYSIS FOR EXTENDED-REACH AND HORIZONTAL WELLS A Thesis by MAXIMILIAN M. LONG Submitted...
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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) Environmental AssessmentsGeoffrey Campbelllong version)Confinement |GeneralGeneral
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Van Gorder, Robert A., E-mail: rav@knights.ucf.edu [Department of Mathematics, University of Central Florida, Orlando, Florida 32816-1364 (United States)
2014-06-15T23:59:59.000Z
In his study of superfluid turbulence in the low-temperature limit, Svistunov [“Superfluid turbulence in the low-temperature limit,” Phys. Rev. B 52, 3647 (1995)] derived a Hamiltonian equation for the self-induced motion of a vortex filament. Under the local induction approximation (LIA), the Svistunov formulation is equivalent to a nonlinear dispersive partial differential equation. In this paper, we consider a family of rotating vortex filament solutions for the LIA reduction of the Svistunov formulation, which we refer to as the 2D LIA (since it permits a potential formulation in terms of two of the three Cartesian coordinates). This class of solutions holds the well-known Hasimoto-type planar vortex filament [H. Hasimoto, “Motion of a vortex filament and its relation to elastica,” J. Phys. Soc. Jpn. 31, 293 (1971)] as one reduction and helical solutions as another. More generally, we obtain solutions which are periodic in the space variable. A systematic analytical study of the behavior of such solutions is carried out. In the case where vortex filaments have small deviations from the axis of rotation, closed analytical forms of the filament solutions are given. A variety of numerical simulations are provided to demonstrate the wide range of rotating filament behaviors possible. Doing so, we are able to determine a number of vortex filament structures not previously studied. We find that the solution structure progresses from planar to helical, and then to more intricate and complex filament structures, possibly indicating the onset of superfluid turbulence.
Zakirjon Kanokov; Juern W. P. Schmelzer; Avazbek K. Nasirov
2009-04-07T23:59:59.000Z
An analysis of a variety of existing experimental data leads to the conclusion on the existence of a resonance mechanism allowing weak magnetic fields to affect biological processes. These fields may either be static magnetic fields comparable in magnitude with the magnetic field of the earth or weak ultra-low frequency time-dependent fields. So far, a generally accepted theoretical model allowing one to understand the effect of magnetic and electric fields on biological processes is not available. By this reason, it is not clear which characteristics of the fields, like magnetic and electric field strength, frequency of change of the field, shape of the electromagnetic wave, the duration of the magnetic or electric influence or some particular combination of them, are responsible for the biological effect. In the present analysis it is shown that external time-independent magnetic fields may cause a resonance amplification of ionic electric currents in biological tissues and, in particular, in the vasculature system due to a Brownian motion of charges. These resonance electric currents may cause necrotic changes in the tissues or blood circulation and in this way significantly affect the biological organism. The magnitude of the magnetic fields leading to resonance effects is estimated, it is shown that it depends significantly on the radius of the blood capillaries.
Modeling Atmospheric Circulation Changes over the North Pacific
Percival, Don
density function (SDF) . essential di#erence between processes -- AR(1) ACVS dies down quickly and variance # 2 # 3. |#| SDF given by s X,# # cov{X t , X t noise; LM if # > 0) . ACVS and SDF given by s Y,# = # 2 # sin(##)#(1 - 2#)#(# + #) ##(# + 1 - #) & S Y
Modeling Atmospheric Circulation Changes over the North Pacific
Percival, Don
function (SDF) Â· essential difference between processes Â AR(1) ACVS dies down quickly (exponentially), so) Â· ACVS and SDF given by sX, cov{Xt, Xt+ } = 2 || 1 - 2 & SX(f) = 2 1 + 2 - 2 cos(2f) , where = 0, Yt is white noise; LM if > 0) Â· ACVS and SDF given by sY, = 2 sin()(1 - 2)( + ) ( + 1 - ) & SY
Modeling Atmospheric Circulation Changes over the North Pacific
Percival, Don
density function (SDF) Â· essential difference between processes Â AR(1) ACVS dies down quickly, then Xt is white noise) Â· ACVS and SDF given by sX, cov{Xt, Xt+ } = 2 || 1 - 2 & SX(f) = 2 1 + 2 - 2 cos; LM if > 0) Â· ACVS and SDF given by sY, = 2 sin()(1 - 2)( + ) ( + 1 - ) & SY (f) = 2 |2 sin(f)|2
February 2002 Modelling The Conveyor Belt Circulation using MICOM
Nadiga, Balasubramanya T. "Balu"
;Climatological SST, Zero flux over ice, Net heating of 17 W/m2 #12;Climatological SST, Zero flux over ice, Net
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David A. Randall; Marat Khairoutdinov
2007-12-14T23:59:59.000Z
The Colorado State University (CSU) Multi-scale Modeling Framework (MMF) is a new type of general circulation model (GCM) that replaces the conventional parameterizations of convection, clouds and boundary layer with a cloud-resolving model (CRM) embedded into each grid column. The MMF that we have been working with is a “super-parameterized” version of the Community Atmosphere Model (CAM). As reported in the publications listed below, we have done extensive work with the model. We have explored the MMF’s performance in several studies, including an AMIP run and a CAPT test, and we have applied the MMF to an analysis of climate sensitivity.
DRILLING MACHINES GENERAL INFORMATION
Gellman, Andrew J.
TC 9-524 Chapter 4 DRILLING MACHINES GENERAL INFORMATION PURPOSE This chapter contains basic information pertaining to drilling machines. A drilling machine comes in many shapes and sizes, from small hand-held power drills to bench mounted and finally floor-mounted models. They can perform operations
Methods of forming a fluidized bed of circulating particles
Marshall, Douglas W. (Blackfoot, ID)
2011-05-24T23:59:59.000Z
There is disclosed an apparatus for forming a fluidized bed of circulating particles. In an embodiment, the apparatus includes a bottom portion having a sidewall, the sidewall defining a curvilinear profile, and the bottom portion configured to contain a bed of particles; and a gas inlet configured to produce a column of gas to carry entrained particles therein. There is disclosed a method of forming a fluidized bed of circulating particles. In an embodiment, the method includes positioning particles within a bottom portion having a sidewall, the sidewall defining a curvilinear profile; producing a column of gas directed upwardly through a gas inlet; carrying entrained particles in the column of gas to produce a fountain of particles over the fluidized bed of circulating particles and subside in the particle bed until being directed inwardly into the column of gas within the curvilinear profile.
Strzalka, J.; Liu, J; Tronin, A; Churbanova, I; Johansson, J; Blasie, J
2009-01-01T23:59:59.000Z
We previously reported the synthesis and structural characterization of a model membrane protein comprised of an amphiphilic 4-helix bundle peptide with a hydrophobic domain based on a synthetic ion channel and a hydrophilic domain with designed cavities for binding the general anesthetic halothane. In this work, we synthesized an improved version of this halothane-binding amphiphilic peptide with only a single cavity and an otherwise identical control peptide with no such cavity, and applied x-ray reflectivity to monolayers of these peptides to probe the distribution of halothane along the length of the core of the 4-helix bundle as a function of the concentration of halothane. At the moderate concentrations achieved in this study, approximately three molecules of halothane were found to be localized within a broad symmetric unimodal distribution centered about the designed cavity. At the lowest concentration achieved, of approximately one molecule per bundle, the halothane distribution became narrower and more peaked due to a component of {approx}19Angstroms width centered about the designed cavity. At higher concentrations, approximately six to seven molecules were found to be uniformly distributed along the length of the bundle, corresponding to approximately one molecule per heptad. Monolayers of the control peptide showed only the latter behavior, namely a uniform distribution along the length of the bundle irrespective of the halothane concentration over this range. The results provide insight into the nature of such weak binding when the dissociation constant is in the mM regime, relevant for clinical applications of anesthesia. They also demonstrate the suitability of both the model system and the experimental technique for additional work on the mechanism of general anesthesia, some of it presented in the companion parts II and III under this title.
Murray, Sophie A; Jackson, David R; Bruinsma, Sean L
2015-01-01T23:59:59.000Z
Data assimilation procedures have been developed for thermospheric models using satellite density measurements as part of the EU Framework Package 7 ATMOP Project. Two models were studied; one a general circulation model, TIEGCM, and the other a semi-empirical drag temperature model, DTM. Results of runs using data assimilation with these models were compared with independent density observations from CHAMP and GRACE satellites throughout solar cycles 23 and 24. Time periods of 60 days were examined at solar minimum and maximum, including the 2003 Hallowe'en storms. The differences between the physical and the semi-empirical models have been characterised. Results indicate that both models tend to show similar behaviour; underestimating densities at solar maximum, and overestimating them at solar minimum. DTM performed better at solar minimum, with both models less accurate at solar maximum. A mean improvement of ~4% was found using data assimilation with TIEGCM. With further improvements, the use of general ...
Sutapa Mukherjee M. Tech
Abstract:- Energy efficiency provided by daylight requires an accurate estimation of the amount of daylight entering a building. The actual daylight illuminance of a room is mainly influenced by the luminance levels and patterns of the sky in the direction of view of the window at that time. The daylight coefficient concept, which considers the changes in the luminance of the sky elements, offers a more effective way of computing indoor daylight illuminances. Recently, Kittler et al. have proposed a new range of 15 standard sky luminance distributions including the CIE (International Commission onIllumination) standard clear sky. Lately, these 15 sky luminance models have been adopted as the CIE Standard General Skies.This paper aims to find out representative CIE (International Commission on Illumination) Standard Clear Sky model(s) for three different seasons-winter solstice, equinox, and summer solstice applicable for prevailing clear sky climatic conditions in India [Roorkee]. Indian measured sky luminance distribution database is available only for Roorkee[29 0 51 ' N; 77 0 53 ' E]. To find out the best match between Indian measured sky luminance distribution and each of five CIE Standard Clear sky models, only sky component of spatial illuminance distribution over the working plane of a room was simulated by MATLABfor three different seasons. Daylight Coefficient method has been applied for the simulation using Indian sky luminance database.The simulation has been done for the room with eight different window orientations ranging from 0 0 to 315 0 with an interval of 45 0 to generate data for the entire sky vault. To find out the
Refractory experience in circulating fluidized bed combustors, Task 7
Vincent, R.Q.
1989-11-01T23:59:59.000Z
This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.
Feasibility of natural circulation heat transport in the ENHS.
Sienicki, J.J.
2002-02-14T23:59:59.000Z
An analysis has been carried out of natural circulation thermal hydraulics in both the primary and intermediate circuits of the Encapsulated Nuclear Heat Source (ENHS). It is established that natural circulation enhanced by gas injection into the primary coolant above the core, or the intermediate coolant above the heat exchange zone, is effective in transporting the nominal core power to the steam generators without the attainment of excessive system temperatures. Uncertainties in thermophysical properties and wall friction have a relatively small effect upon the calculated best estimate primary and intermediate coolant system temperature rises.
Feasibility of Natural Circulation Heat Transport in the ENHS
Sienicki, James J. [Argonne National Laboratory, 9700 S. Cass Avenue Argonne, IL 60439 (United States)
2002-07-01T23:59:59.000Z
An analysis has been carried out of natural circulation thermal hydraulics in both the primary and intermediate circuits of the Encapsulated Nuclear Heat Source (ENHS). It is established that natural circulation enhanced by gas injection into the primary coolant above the core, or the intermediate coolant above the heat exchange zone, is effective in transporting the nominal core power to the steam generators without the attainment of excessive system temperatures. Uncertainties in thermophysical properties and wall friction have a relatively small effect upon the calculated best estimate primary and intermediate coolant system temperature rises. (authors)
SURFACE CIRCULATION AND VENTILATION Lynne D. Talley(1)
Talley, Lynne D.
SURFACE CIRCULATION AND VENTILATION Lynne D. Talley(1) , Rana Fine(2) , Rick Lumpkin (3) , Nikolai by high frequency radars. Ventilation and upwelling processes connect the surface layer and underlying quantitative information on formation rates and residence times, and compelling evidence of decadal ventilation
UNCORRECTEDPROOF Effect of channel bifurcation on residual estuarine circulation
Voulgaris, George
western channel. This is the result of the fact that the magnitude of residual flow scales with the water throughout the water column of the channel while in the adjacent shoals the residual flow is directedUNCORRECTEDPROOF Effect of channel bifurcation on residual estuarine circulation: Winyah Bay, South
Decadal variability of the Atlantic Meridional Overturning Circulation
Buckley, Martha Weaver
2011-01-01T23:59:59.000Z
In the mean, the Atlantic Ocean transports 1 to 1.5 PW of heat northward, and estimates suggest that 60% of this heat transport is associated with a circulation that reaches the cold waters of the abyss. Due to the role ...
RADIOGENIC ISOTOPES: TRACERS OF PAST OCEAN CIRCULATION AND EROSIONAL INPUT
Jellinek, Mark
of Earth Sciences Institute for Isotope Geology and Mineral Resources EidgenoÂ¨ssische Technische Hochschule the global mixing time of the ocean (Nd, Pb, Hf, and, in addition, Be). Their isotopic composition global ocean circulation system is largely driven by the sinking of cold, saline (and therefore dense
DMEC-1 Pressurized Circulating Fluidized-Bed Demonstration Project
Kruempel, G.E.; Ambrose, S.J. [Midwest Power, Des Moines, IA (United States); Provol, S.J. [Pyropower Corp., San Diego, CA (United States)
1992-12-01T23:59:59.000Z
The DMEC-1 project will demonstrate the use of Pyropower`s PYROFLOW pressurized circulating fluidized bed technology to repower an existing coal fired generating station. This will be the first commercial application of this technology in the world. The project is now in budget period 1, the preliminary design phase.
Waste Heat Recovery Using a Circulating Heat Medium Loop
Manning, E., Jr.
1981-01-01T23:59:59.000Z
by a circulating heat medium loop where waste heat is recovered for useful purposes. The heat medium chosen is turbine fuel. It is pumped around the refinery to pick up heat at the crude distilling unit, the hydrocracker, the catalytic cracker...
Benchmarking assessment of RELAP5/MOD3 for the low flow and natural circulation experiment
Martin, R.P. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Taylor, B.K. [Westinghouse Savannah River Co., Aiken, SC (United States)
1992-11-01T23:59:59.000Z
The RELAP5/MOD3 code was assessed against experimental thermal hydraulics data for a 12.5 foot test section comprised of two vertical concentric tubes with water flowing upward in the tubes. The inner tubewas stainless steel and uniformly heated. ne outer tube was transparent polycarbonate (lexan) and unheated. The experimental procedure incorporated a test matrix of 24 tests to address single- and two-phase flow, forced and natural circulation flow and heated and unheated fluid. The tests were conducted at system pressures of 14.7 and 17.0 psia. Nine of the tests representing the full range of test conditions were analyzed using RELAP5/MOD3. RELAP5/MOD3 analysis of the tests yielded general agreement with experiment with regard to the prediction of forced flow and natural circulation trends. However, a number of deficiencies were observed in the RELAP5/MOD3 treatment and these, along with recommendations for their resolution, are described in the paper.
Benchmarking assessment of RELAP5/MOD3 for the low flow and natural circulation experiment
Martin, R.P. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Taylor, B.K. (Westinghouse Savannah River Co., Aiken, SC (United States))
1992-01-01T23:59:59.000Z
The RELAP5/MOD3 code was assessed against experimental thermal hydraulics data for a 12.5 foot test section comprised of two vertical concentric tubes with water flowing upward in the tubes. The inner tubewas stainless steel and uniformly heated. ne outer tube was transparent polycarbonate (lexan) and unheated. The experimental procedure incorporated a test matrix of 24 tests to address single- and two-phase flow, forced and natural circulation flow and heated and unheated fluid. The tests were conducted at system pressures of 14.7 and 17.0 psia. Nine of the tests representing the full range of test conditions were analyzed using RELAP5/MOD3. RELAP5/MOD3 analysis of the tests yielded general agreement with experiment with regard to the prediction of forced flow and natural circulation trends. However, a number of deficiencies were observed in the RELAP5/MOD3 treatment and these, along with recommendations for their resolution, are described in the paper.
Traditional and novel approaches to palaeoclimate modelling
Crucifix, Michel
2012-01-01T23:59:59.000Z
Palaeoclimate archives contain information on climate variability, trends and mechanisms. Models are developed to explain observations and predict the response of the climate system to perturbations, in particular perturbations associated with the anthropogenic influence. Here, we review three classical frameworks of climate modelling: conceptual, simulator-based (including general circulation models and Earth system models of intermediate complexity), and statistical. The conceptual framework aims at a parsimonious representation of a given climate phenomenon; the simulator-based framework connects physical and biogeochemical principles with phenomena at different spatial and temporal scales; and statistical modelling is a framework for inference from observations, given hypotheses on systematic and random effects. Recently, solutions have been proposed in the literature to combine these frameworks, and new concepts have emerged: the emulator (a statistical, computing efficient surrogate for the simulator) a...
Mathematical Modeling Arnold Neumaier
Neumaier, Arnold
· Blood circulation models 4 #12;Meteorology · Weather prediction · Climate prediction (global warming (genetic variability) Chemical engineering · Chemical equilibrium · Planning of production units Chemistry recognition · Face recognition Economics · Labor data analysis Electrical engineering · Stability of electric
Experimental Study of the Circulation Air Volume of Recirculation Evaporative Cooling
Xiong, J.; Liu, Z.; Wang, C.; Chen, G.
2006-01-01T23:59:59.000Z
This paper introduces the technology of re-circulation evaporative cooling (REC), which uses a portion of supply air as secondary air to make cool water used to indirectly cool outside air through a heat exchanger. The circulation volume...
MFIX simulation of NETL/PSRI challenge problem of circulating fluidized bed
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Li, Tingwen; Dietiker, Jean-Francois; Shahnam, Mehrdad
2012-12-01T23:59:59.000Z
In this paper, numerical simulations of NETL/PSRI challenge problem of circulating fluidized bed (CFB) using the open-source code Multiphase Flow with Interphase eXchange (MFIX) are reported. Two rounds of simulation results are reported including the first-round blind test and the second-round modeling refinement. Three-dimensional high fidelity simulations are conducted to model a 12-inch diameter pilot-scale CFB riser. Detailed comparisons between numerical results and experimental data are made with respect to axial pressure gradient profile, radial profiles of solids velocity and solids mass flux along different radial directions at various elevations for operating conditions covering different fluidization regimes. Overall, the numerical results show that CFD can predict the complex gas–solids flow behavior in the CFB riser reasonably well. In addition, lessons learnt from modeling this challenge problem are presented.
MFIX simulation of NETL/PSRI challenge problem of circulating fluidized bed
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Li, Tingwen; Dietiker, Jean-Francois; Shahnam, Mehrdad
2012-12-01T23:59:59.000Z
In this paper, numerical simulations of NETL/PSRI challenge problem of circulating fluidized bed (CFB) using the open-source code Multiphase Flow with Interphase eXchange (MFIX) are reported. Two rounds of simulation results are reported including the first-round blind test and the second-round modeling refinement. Three-dimensional high fidelity simulations are conducted to model a 12-inch diameter pilot-scale CFB riser. Detailed comparisons between numerical results and experimental data are made with respect to axial pressure gradient profile, radial profiles of solids velocity and solids mass flux along different radial directions at various elevations for operating conditions covering different fluidization regimes. Overall, the numericalmore »results show that CFD can predict the complex gas–solids flow behavior in the CFB riser reasonably well. In addition, lessons learnt from modeling this challenge problem are presented.« less
Deterministic treatment of model error in geophysical data assimilation
Carrassi, Alberto
2015-01-01T23:59:59.000Z
This chapter describes a novel approach for the treatment of model error in geophysical data assimilation. In this method, model error is treated as a deterministic process fully correlated in time. This allows for the derivation of the evolution equations for the relevant moments of the model error statistics required in data assimilation procedures, along with an approximation suitable for application to large numerical models typical of environmental science. In this contribution we first derive the equations for the model error dynamics in the general case, and then for the particular situation of parametric error. We show how this deterministic description of the model error can be incorporated in sequential and variational data assimilation procedures. A numerical comparison with standard methods is given using low-order dynamical systems, prototypes of atmospheric circulation, and a realistic soil model. The deterministic approach proves to be very competitive with only minor additional computational c...
Short-circuiting of the overturning circulation in the Antarctic Circumpolar Current
Miami, University of
LETTERS Short-circuiting of the overturning circulation in the Antarctic Circumpolar Current flows over complex ocean-floor topography, giving rise to a short circuit of the overturning circulation. Mixing processes in the Antarctic Circumpolar Current are key to this circulation, because they con- trol
Physiological relevance of the changes in hemodynamics for circulating blood cells in
103 Chapter 5 Physiological relevance of the changes in hemodynamics for circulating blood cells that these changes in the mechanical stimuli might have on the activation state of circulating blood cells have never the magnitude and duration of the shear stresses acting on blood cells circulating inside AAAs
White, L.S.
1990-07-01T23:59:59.000Z
This report presents the results of a study of the lessons learned during the design, testing, and operation of gas-cooled reactor coolant circulators. The intent of this study is to identify failure modes and problem areas of the existing circulators so this information can be incorporated into the design of the circulators for the New Production Reactor (NPR)-Modular High-Temperature Gas Cooled Reactor (MHTGR). The information for this study was obtained primarily from open literature and includes data on high-pressure, high-temperature helium test loop circulators as well as the existing gas cooled reactors worldwide. This investigation indicates that trouble free circulator performance can only be expected when the design program includes a comprehensive prototypical test program, with the results of this test program factored into the final circulator design. 43 refs., 7 tabs.
A toolkit for building earth system models
Foster, I.
1993-03-01T23:59:59.000Z
An earth system model is a computer code designed to simulate the interrelated processes that determine the earth's weather and climate, such as atmospheric circulation, atmospheric physics, atmospheric chemistry, oceanic circulation, and biosphere. I propose a toolkit that would support a modular, or object-oriented, approach to the implementation of such models.
A toolkit for building earth system models
Foster, I.
1993-03-01T23:59:59.000Z
An earth system model is a computer code designed to simulate the interrelated processes that determine the earth`s weather and climate, such as atmospheric circulation, atmospheric physics, atmospheric chemistry, oceanic circulation, and biosphere. I propose a toolkit that would support a modular, or object-oriented, approach to the implementation of such models.
Apparatus and method for determining solids circulation rate
Ludlow, J. Christopher (Morgantown, WV); Spenik, James L. (Morgantown, WV)
2012-02-14T23:59:59.000Z
The invention relates to a method of determining bed velocity and solids circulation rate in a standpipe experiencing a moving packed bed flow, such as the in the standpipe section of a circulating bed fluidized reactor The method utilizes in-situ measurement of differential pressure over known axial lengths of the standpipe in conjunction with in-situ gas velocity measurement for a novel application of Ergun equations allowing determination of standpipe void fraction and moving packed bed velocity. The method takes advantage of the moving packed bed property of constant void fraction in order to integrate measured parameters into simultaneous solution of Ergun-based equations and conservation of mass equations across multiple sections of the standpipe.
Four Rivers second generation Pressurized Circulating Fluidized Bed Combustion Project
Holley, E.P.; Lewnard, J.J. [Air Products and Chemicals, Inc. (United States); von Wedel, G. [LLB Lurgi Lentjes Babcock Energietechnik (GmbH); Richardson, K.W. [Foster Wheeler Energy Corp. (United States); Morehead, H.T. [Westinghouse Electric Corp. (United States)
1995-04-01T23:59:59.000Z
Air Products has been selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second generation Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The four Rivers Energy Project (Four Rivers) will produce up to 400,000 lb/hr steam, or an equivalent gross capacity of 95 MWe. The unit will be used to repower an Air Products chemicals manufacturing facility in Calvert City, Kentucky.
NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project. 1990 Annual report
Not Available
1992-02-01T23:59:59.000Z
The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)
Fedorov, Alexey [Yale University] [Yale University
2013-11-23T23:59:59.000Z
The central goal of this research project is to understand the properties of the ocean meridional overturning circulation (MOC) – a topic critical for understanding climate variability and stability on a variety of timescales (from decadal to centennial and longer). Specifically, we have explored various factors that control the MOC stability and decadal variability in the Atlantic and the ocean thermal structure in general, including the possibility abrupt climate change. We have also continued efforts on improving the performance of coupled ocean-atmosphere GCMs.
Stability Analysis on Single-Phase Natural Circulation in Argonne Lead Loop Facility
Wu, Qiao [Oregon State University, Corvallis, OR 97331-4501 (United States); Sienicki, James J. [Argonne National Laboratory, 9700 S. Cass Avenue Argonne, IL 60439 (United States)
2002-07-01T23:59:59.000Z
One-dimensional linear stability analysis was performed for single-phase lead-bismuth eutectic natural circulation. The Nyquist criterion and a root search method were employed to find the linear stability boundary of both forward and backward circulations. It was found that the natural circulations could be linearly unstable in a high Reynolds number region. Increasing loop friction makes a forward circulation more stable, but destabilizes the corresponding backward circulation under the same heating/cooling conditions. The characteristic wavelength of an unstable disturbance is roughly equal to the entire loop length. (authors)
Gautam, M.; Jurewicz, J.; Heping, Y.; Clifton, K.
1992-07-01T23:59:59.000Z
This research program involves two major aspects. First, to evaluate techniques to effectively probe the polydisperse gas-solid flows and second, to apply these techniques to study the gas-solid flow structure and clusters in the riser of a circulating fluidized bed riser. Amongst the non-intrusive techniques a modified laser Doppler technique based on the fluorescence-emission concept has been adopted and the other techniques involve pitot-static pressure probes. A circulating fluidized bed (CFB) facility has been designed, built and is currently operational at West Virginia University. The design provides for maximum versatility in investigating the hydrodynamics of the CFB riser. Two stage cyclones are employed to capture the particles exhausted from the riser. Measurements of gas velocity distribution were carried out in the circulating fluidized bed riser. with particles having a mean diameter of 112 {mu}m and a density of 2305 kg/m{sup 3} and another set of particles with a mean diameter of 145 {mu}m and a density of 2245 kg/m{sup 3}. The experimental results showed that the local gas velocity varied with the radial position, elevation, solids circulation rate, superficial velocity and particle size. A general formula for gas velocity distribution in the circulating fluidized bed riser was obtained based on the particle circulation, superficial velocity and particle diameter. The pressure drops across the L-valve were also studied for different particle sizes, L-valve diameters and aeration. The solids flowrate was found to be a function of the L-valve geometry, operating parameters and solids properties. Pressure drop of L-valve increases with increasing solids diameter and decreasing diameter of the L-valve. Pressure drop across standpipe increases as the solids diameter and diameter of the standpipe decrease.
The mean-field solar dynamo with double cell meridional circulation pattern
Pipin, V V
2013-01-01T23:59:59.000Z
The paper addresses the question whether the dynamo remains of the solar type if it is coupled with the two-cell in radius meridional circulation pattern. The answer is positive for a wide class of dynamo models that take into account the subsurface rotational shear. We show that the Gleisberg-type cycles, representing variations of 11-year on the centure time scale, can be generated due to a nonlinear resonance between the dynamo wave, and the large-scale magnetic field amplification in the middle of the convection zone as a result of the convergent meridional shearing flows. The conditions of such resonant interaction depends on the speed of the meridional flow and other details of the model.
Breiner, Evelyn Marie
1988-01-01T23:59:59.000Z
/MOD1 has been assessed against natural circulation data from facilities such as: MIST/OTIS, FLECHT-SEASET, FRIGG Loop Tests, Semiscale, and LOFI (Refs. 9-14). These assessment activities involve experimentation and computer modeling...ANALYSIS OF A NATURAL CIRCULATION COOLDOWN TRANSIENTS IN A WESTINGHOUSE PRESSURIZED WATER REACTOR USING TRAC-PF1/MOD1 AND TRAC-PF I/MOD2 A Thesis by EVELYN MARIE BREINER Submitted to the Office of Graduate Studies of Texas A&M University...
Broader source: Energy.gov [DOE]
The Assistant General Counsel for General Law is responsible for providing legal review and general legal services to DOE with regard to matters involving: fiscal, personnel, labor relations,...
Fan, Jiwen; Rosenfeld, Daniel; Ding, Yanni; Leung, Lai-Yung R.; Li, Zhanqing
2012-05-10T23:59:59.000Z
Aerosol indirect effects, i.e., the interactions of aerosols with clouds by serving as cloud condensation nuclei (CCN) or ice nuclei (IN), constitute the largest uncertainty in climate forcing and projection. Previous IPCC reported aerosol indirect forcing is negative, which does not account for aerosol-convective cloud interactions because the complex processes involved are poorly understood and represented in climate models. Here we report that aerosol indirect effect on deep convective cloud systems can lead to enhanced regional convergence and a strong top-of atmosphere (TOA) warming. Aerosol invigoration effect on convection can result in a strong radiative warming in the atmosphere (+5.6 W m-2) due to strong night-time warming, a lofted latent heating, and a reduced diurnal temperature difference, all of which could remarkably impact regional circulation and modify weather systems. We further elucidated how aerosols change convective intensity, diabatic heating, and regional circulation under different environmental conditions and concluded that wind shear and cloud base temperature play key roles in determining the significance of aerosol invigoration effect for convective systems.
Blei, David M.
2011-01-01T23:59:59.000Z
characterizes the deviation of the response from its conditional mean. The simplest example is linear regression. Generalized linear models (GLMs) extend linear regression to many types of response variables (Mc a linear function; a non-linear function may be applied to the output of the linear function, but only one
General Relativistic Radiative Transfer
S. Knop; P. H. Hauschildt; E. Baron
2006-11-30T23:59:59.000Z
We present a general method to calculate radiative transfer including scattering in the continuum as well as in lines in spherically symmetric systems that are influenced by the effects of general relativity (GR). We utilize a comoving wavelength ansatz that allows to resolve spectral lines throughout the atmosphere. The used numerical solution is an operator splitting (OS) technique that uses a characteristic formal solution. The bending of photon paths and the wavelength shifts due to the effects of GR are fully taken into account, as is the treatment of image generation in a curved spacetime. We describe the algorithm we use and demonstrate the effects of GR on the radiative transport of a two level atom line in a neutron star like atmosphere for various combinations of continuous and line scattering coefficients. In addition, we present grey continuum models and discuss the effects of different scattering albedos on the emergent spectra and the determination of effective temperatures and radii of neutron star atmospheres.
Generalized Dirac operators and superconnections
G. Roepstorff; Ch. Vehns
1999-11-04T23:59:59.000Z
Motivated by the supersymmetric version of Dirac's theory, chiral models in field theory, and the quest of a geometric fundament for the Standard Model, we describe an approach to the differential geometry of vector bundles on (semi)-Riemannian manifolds based on the concepts of superspaces, superalgebras, superconnections, and generalized Dirac operators. In doing so we stay within the realm of commutative geometry.
Non-adiabatic pumping in an oscillating-piston model
Maya Chuchem; Thomas Dittrich; Doron Cohen
2012-04-02T23:59:59.000Z
We consider the prototypical "piston pump" operating on a ring, where a circulating current is induced by means of an AC driving. This can be regarded as a generalized Fermi-Ulam model, incorporating a finite-height moving wall (piston) and non trivial topology (ring). The amount of particles transported per cycle is determined by a layered structure of phase-space. Each layer is characterized by a different drift velocity. We discuss the differences compared with the adiabatic and Boltzmann pictures, and highlight the significance of the "diabatic" contribution that might lead to a counter-stirring effect.
Regional Climate Modeling: Progress, Challenges, and Prospects
Wang, Yuqing; Leung, Lai R.; McGregor, John L.; Lee, Dong-Kyou; Wang, Wei-Chyung; Ding, Yihui; Kimura, Fujio
2004-12-01T23:59:59.000Z
Regional climate modeling with regional climate models (RCMs) has matured over the past decade and allows for meaningful utilization in a broad spectrum of applications. In this paper, latest progresses in regional climate modeling studies are reviewed, including RCM development, applications of RCMs to dynamical downscaling for climate change assessment, seasonal climate predictions and climate process studies, and the study of regional climate predictability. Challenges and potential directions of future research in this important area are discussed, with the focus on those to which less attention has been given previously, such as the importance of ensemble simulations, further development and improvement of regional climate modeling approach, modeling extreme climate events and sub-daily variation of clouds and precipitation, model evaluation and diagnostics, applications of RCMs to climate process studies and seasonal predictions, and development of regional earth system models. It is believed that with both the demonstrated credibility of RCMs’ capability in reproducing not only monthly to seasonal mean climate and interannual variability but also the extreme climate events when driven by good quality reanalysis and the continuous improvements in the skill of global general circulation models (GCMs) in simulating large-scale atmospheric circulation, regional climate modeling will remain an important dynamical downscaling tool for providing the needed information for assessing climate change impacts and seasonal climate predictions, and a powerful tool for improving our understanding of regional climate processes. An internationally coordinated effort can be developed with different focuses by different groups to advance regional climate modeling studies. It is also recognized that since the final quality of the results from nested RCMs depends in part on the realism of the large-scale forcing provided by GCMs, the reduction of errors and improvement in physics parameterizations in both GCMs and RCMs remain a priority for climate modeling community.
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 ScienceandMesa del(ANL-IN-03-032) -Less is more:culturingProtonAPRIL/MAY9Hydrate ModelingB General
PPPL and General Atomics scientists make breakthrough in understanding...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
The left image models the response that suppressed the ELMs while the right image shows a response that was ineffective. Simulation by General Atomics. Researchers from General...
Pressurized circulating fluidized-bed combustion for power generation
Weimer, R.F.
1995-08-01T23:59:59.000Z
Second-generation Pressurized Circulating Fluidized Bed Combustion (PCFBC) is the culmination of years of effort in the development of a new generation of power plants which can operate on lower-quality fuels with substantially improved efficiencies, meet environmental requirements, and provide a lower cost of electricity. Air Products was selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second-generation PCFBC technology, to be located at an Air Products chemicals manufacturing facility in Calvert City, Kentucky. This paper describes the second-generation PCFBC concept and its critical technology components.
Four Rivers second generation pressurized circulating fluidized bed combustion project
Holley, E.P.; Lewnard, J.J. [Air Products and Chemicals, Inc., Allentown, PA (United States); Wedel, G. von; Richardson, K.W.; Morehead, H.T.
1995-12-31T23:59:59.000Z
Air Products has been selected in the DOE Clean Coal Technology Round 5 program to build, own, and operate the first commercial power plant using second generation Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The Four Rivers Energy Project (Four Rivers) will produce approximately 70 MW electricity, and will produce up to 400,000 lb/hr steam, or an equivalent gross capacity of 95 MWe. The unit will be used to repower an Air Products chemicals manufacturing facility in Calvert City, Kentucky.
NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project. Annual report, 1988
Not Available
1991-01-01T23:59:59.000Z
This Annual Report on Colorado-Ute Electric Association`s NUCLA Circulating Fluidized Bed (CFB) Demonstration Program covers the period from February 1987 through December 1988. The outline for presentation in this report includes a summary of unit operations along with individual sections covering progress in study plan areas that commenced during this reporting period. These include cold-mode shakedown and calibration, plant commercial performance statistics, unit start-up (cold), coal and limestone preparation and handling, ash handling system performance and operating experience, tubular air heater, baghouse operation and performance, materials monitoring, and reliability monitoring. During this reporting period, the coal-mode shakedown and calibration plan was completed. (VC)
Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks
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 for4,645 3,625govInstrumentstdmadapInactiveVisitingContract ManagementDiscovering HowAnaDynamic Switching of the Spin Circulation
Property:Building/SPElectrtyUsePercCirculationFans | Open Energy
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 You are beingZealand Jump to: navigation,Pillar Group BV JumpInformation SPElectrtyUsePercCirculationFans Jump to:
CFD analyses of natural circulation in the air-cooled reactor cavity cooling system
Hu, R. [Nuclear Engineering Division, Argonne National Laboratory, Argonne IL (United States); Pointer, W. D. [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN (United States)
2013-07-01T23:59:59.000Z
The Natural Convection Shutdown Heat Removal Test Facility (NSTF) is currently being built at Argonne National Laboratory, to evaluate the feasibility of the passive Reactor Cavity Cooling System (RCCS) for Next Generation Nuclear Plant (NGNP). CFD simulations have been applied to evaluate the NSTF and NGNP RCCS designs. However, previous simulations found that convergence was very difficult to achieve in simulating the complex natural circulation. To resolve the convergence issue and increase the confidence of the CFD simulation results, additional CFD simulations were conducted using a more detailed mesh and a different solution scheme. It is found that, with the use of coupled flow and coupled energy models, the convergence can be greatly improved. Furthermore, the effects of convection in the cavity and the effects of the uncertainty in solid surface emissivity are also investigated. (authors)
Feedbacks in a simple prognostic tropical climate model
Sherwood, S.C. (Scripps Institution of Oceanography, La Jolla, CA (United States))
1999-07-01T23:59:59.000Z
A simple four-cell model of the tropical atmosphere in equilibrium with its boundaries is introduced, which can support a variable diabatic circulation and prognostic temperature and humidity profiles. The model is used to predict atmospheric perturbations away from the observed base state. Prognostic variables include radiation, surface fluxes, and dynamic transports, with temperature and water vapor levels determined by conservation constraints. The model includes a specially developed water vapor scheme that performs favorably compared with observations. The model is used to simulate the local and nonlocal sensitivity of the tropical maritime atmosphere to changes in surface temperature and other boundary conditions at very large horizontal scales. The main findings are as follows: (i) The sensitivity of boundary layer convergence to sea surface temperature (SST) variations depends on the behavior of convective heating over cooler regions and may be overestimated by heuristic models that ignore or oversimplify thermodynamic and radiative constraints; (ii) The maintenance of humidity equilibrium over weakly convective areas is modulated by local radiative feedback; (iii) Evaporation feedbacks on SST may be overestimated by heuristic arguments that do not carefully treat atmospheric water transport. An explanation for the constant-relative humidity behavior of general circulation models under climate changes is also offered based on the results.
Fundamental demonstration of natural circulation feasibility for an HLMC reactor
Sienicki, J.J.; Spencer, B.W.; Farmer, M.T.
1999-07-01T23:59:59.000Z
Concepts are being developed and evaluated at Argonne National Laboratory for a smaller nuclear steam supply system with proliferation-resistant features targeted for export to developing countries. Specific features of interest here include low reactor power [300 MW(thermal)]; utilization of inert heavy-liquid-metal coolant (HLMC), namely, lead-bismuth eutectic (T{sub mp} = 125 C), eliminating concerns over metal-water reactions; 15-yr core lifetime, enabling access to fissile materials to be restricted by design; and reliance on purely natural-circulation coolant heat transport, eliminating primary system coolant pumps. Evaluation of this concept is being carried out in stages. The stage 1 investigations to which the results presented in this paper belong are directed at establishing the basic feasibility of the concept through the application of first-principles analyses. This approach is warranted while detailed aspects of the core design are yet to be determined. The objective of the present work is to demonstrate at a fundamental level the feasibility of utilizing natural-circulation coolant heat transport with the HLMC.
Global impact of smoke aerosols from landscape fires on climate and the Hadley circulation
Tosca, M. G; Randerson, J. T; Zender, C. S
2013-01-01T23:59:59.000Z
of biomass burn- ing aerosol on the monsoon circulationA. , and Rudich, Y. : Aerosol invigoration and restructuring2011. Albrecht, B. A. : Aerosols, cloud microphysics, and
FLUID FLOW CHARACTERISTICS OF A HEADER FOR A SINGLE-PASS, CIRCULATING...
Office of Scientific and Technical Information (OSTI)
of a header for a circulating fuel reactor are presented. Description of test equipment and graphical and tabular representation of results are included. (auth) ...
Computer support to run models of the atmosphere. Final report
Fung, I.
1996-08-30T23:59:59.000Z
This research is focused on a better quantification of the variations in CO{sub 2} exchanges between the atmosphere and biosphere and the factors responsible for these exchangers. The principal approach is to infer the variations in the exchanges from variations in the atmospheric CO{sub 2} distribution. The principal tool involves using a global three-dimensional tracer transport model to advect and convect CO{sub 2} in the atmosphere. The tracer model the authors used was developed at the Goddard institute for Space Studies (GISS) and is derived from the GISS atmospheric general circulation model. A special run of the GCM is made to save high-frequency winds and mixing statistics for the tracer model.
Options for Cryogenic Load Cooling with Forced Flow Helium Circulation
Peter Knudsen, Venkatarao Ganni, Roberto Than
2012-06-01T23:59:59.000Z
Cryogenic pumps designed to circulate super-critical helium are commonly deemed necessary in many super-conducting magnet and other cooling applications. Acknowledging that these pumps are often located at the coldest temperature levels, their use introduces risks associated with the reliability of additional rotating machinery and an additional load on the refrigeration system. However, as it has been successfully demonstrated, this objective can be accomplished without using these pumps by the refrigeration system, resulting in lower system input power and improved reliability to the overall cryogenic system operations. In this paper we examine some trade-offs between using these pumps vs. using the refrigeration system directly with examples of processes that have used these concepts successfully and eliminated using such pumps
Nucla circulating atmospheric fluidized bed demonstration project. Final report
Not Available
1991-10-01T23:59:59.000Z
Colorado-Ute Electric Association began a study to evaluate options for upgrading and extending the life of its Nucla power station in 1982. Located in southwestern Colorado near the town of Nucla, this station was commissioned in 1959 with a local bituminous coal as its design fuel for three identical stoker-fired units, each rated at 12.6 MW(e). Poor station efficiency, high fuel costs, and spiraling boiler maintenance costs forced the Nucla Station into low priority in the CUEA dispatch order as early as 1981. Among the options CUEA considered was to serve as a host utility to demonstrate Atmospheric Fluidized Bed Combustion (AFBC) technology. The anticipated environmental benefits and apparent attractive economics of a circulating AFBC led to Colorado-Ute`s decision to proceed with the design and construction of a demonstration project in 1984 at the Nucla facility.
Wind Turbine Blockset General Overview
Wind Turbine Blockset in Saber General Overview and Description of the Models Florin Iov, Adrian Turbine Blockset in Saber Abstract. This report presents a new developed Saber Toolbox for wind turbine, optimize and design wind turbines". The report provides a quick overview of the Saber and then explains
1 Drivers of the projected changes to the Pacific Ocean 2 equatorial circulation
Paris-Sud XI, Université de
1 Drivers of the projected changes to the Pacific Ocean 2 equatorial circulation 3 A. Sen Gupta,1 A), 29 Drivers of the projected changes to the Pacific Ocean equatorial 30 circulation, Geophys. Res. Lett., 39, LXXXXX, doi:10.1029/ 31 2012GL051447. 32 1. Introduction 33 [2] The equatorial Pacific Ocean
PECS 2004 MRIDA -MXICO Simulations of the Influence of the West Caribbean Sea Circulation and
Ezer,Tal
PECS 2004 Â MÃ?RIDA - MÃ?XICO Simulations of the Influence of the West Caribbean Sea Circulation of South Carolina, Columbia, SC 29208, USA. email: bjorn@msci.sc.edu Keywords: Caribbean Sea; Meso by variations of the flow near the reef and the transports between the MBRS and the Caribbean Sea circulation
Satterfield, Michael Carey
2005-02-17T23:59:59.000Z
EVALUATION OF THE EFFECT OF PROGESTERONE CIDR DEVICES ON CIRCULATING LEVELS... CIDR DEVICES ON CIRCULATING LEVELS OF PROGESTERONE IN CYCLIC EWES A Thesis by MICHAEL CAREY SATTERFIELD Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved...
Wind- and Buoyancy-modulated Along-shore Circulation over the Texas-Louisiana Shelf
Zhang, Zhaoru
2013-07-22T23:59:59.000Z
Numerical experiments are used to study the wind- and buoyancy-modulated along-shore circulation over the Texas-Louisiana continental shelf inshore of 50-m water depth. Most attention is given to circulation in the non-summer flow regime. A major...
Vertical Heat Transport by Ocean Circulation and the Role of Mechanical and Haline Forcing
England, Matthew
suggest that heat can be pumped downward by the upper limb of the meridional overturning circulation the earth's climate, with the upper 2.5 m of the ocean able to store as much heat as the entire atmosphereVertical Heat Transport by Ocean Circulation and the Role of Mechanical and Haline Forcing JAN D
Vallis, Geoff
A Theory of Deep Stratification and Overturning Circulation in the Ocean MAXIM NIKURASHIN overturning circulation in an idealized single-basin ocean with a circumpolar channel is presented. The theory; and consistently accounts for the interaction between the circumpolar channel and the rest of the ocean. The theory
Ocean Heat Transport , Overturning Circulations, and some fine-resolution ASOF dynamics
thermal agitation -internal energy of the fluid is typically 10 orders of magnitude greater thanOcean Heat Transport , Overturning Circulations, and some fine-resolution ASOF dynamics P.B. Rhines & S. HÃ¤kkinen #12;Â· Many basic tenets of ocean circulation are being challenged, and they relate
Monge, Juan
2012-10-19T23:59:59.000Z
The economic impacts of a government-funded, forest-based sequestration program were analyzed under two different payment schemes. The impacts were obtained by developing a regional, static CGE model built to accommodate a modified IMPLAN SAM for a...
Monge, Juan
2012-10-19T23:59:59.000Z
The economic impacts of a government-funded, forest-based sequestration program were analyzed under two different payment schemes. The impacts were obtained by developing a regional, static CGE model built to accommodate a modified IMPLAN SAM for a...
Newton, James Edward
1982-01-01T23:59:59.000Z
calculat1on y1elded a I ground. state conf1gurat1on in which the bonding orbital has an occu- pation number of 1. 97 and the antibond1ng orbital has an occupat1on number of 0. 03 electrons. Both Pauling and Griffith geometr1es of Nn(0 )(H C H ) y1... Geometries. Basis sets. . Results Fenske-Hall molecular orbi tal calculations. Restricted Hartree-Fock-Roothaan-Configuration Interaction calculations. 56 58 59 ~ ~ 59 ~ ~ 61 62 62 65 Generalized Molecular Orbi tal-Conf i gurati on Interaction...
Graves, S.L.; Beavers, W.M.; Niederhofer, J.D.
1984-05-01T23:59:59.000Z
During the drilling of coalbed methane wells in the Black Warrior Basin, the possibility of penetrating a highly permeable fault or fracture zone is likely. These fracture zones, and occasionally the faults, are the source of large quantities of water. When air is being used as the drilling medium, problems may arise with producing and disposing of the formation water. When rotary drilling with fluid, loss of returns may also become a problem. The use of conventional lost circulation materials have been demonstrated-in this situation--to be both ineffective and expensive. Also, lost circulation materials substantially reduce the effective secondary permeability of the coal seams, severely limiting the ultimate methane production potential of the well. If the wellbore is generally competent, one inexpensive solution to the problem is to drill with air to a point where surface recovery tanks are full of produced formation water. Drilling can continue by switching to conventional fluid drilling until the surface storage tanks are pumped dry. This process of alternating fluid and air drilling can be continued until reaching total depth. Structural geologic information, available for the coal-bearing formations in the Black Warrior Basin, documents the occurrence of numerous fault and fracture zones. A combination air and fluid drilling technique may prove to be advantageous to coalbed methane operations in this and other areas with similar hydrologic and geologic conditions. Recently, this technique was successfully utilized on TRW, Inc., coalbed methane wells in Tuscaloosa County, Alabama.
Modelling the stratospheric polar vortex and its changes for GHGs increase and ozone depletion.
Greatbatch, Richard
general circulation model (Manzini et al JGR 1997). Top: 0.01 hPa (80 km) Parameterization of a gravity boundary conditions, specified SSTs and ICE. 20 (or 30)-year simulations. The focus is on the Arctic. #12-HadGISS-HadGISS-HadSST & ICE 3.7 ppbv3.4 ppbv0.8 ppbvOrg. CL m. r. 372 ppmv353 ppmv317 ppmvCO2 m. r. 320 ppbv310 ppbv295 ppbvN2
Karami, K., E-mail: kkarami@uok.ac.ir [Department of Physics, University of Kurdistan, Pasdaran St., Sanandaj (Iran, Islamic Republic of)
2010-01-01T23:59:59.000Z
Author of ref. 1, M.R. Setare (JCAP 01 (2007) 023), by redefining the event horizon measured from the sphere of the horizon as the system's IR cut-off for an interacting holographic dark energy model in a non-flat universe, showed that the generalized second law of thermodynamics is satisfied for the special range of the deceleration parameter. His paper includes an erroneous calculation of the entropy of the cold dark matter. Also there are some missing terms and some misprints in the equations of his paper. Here we present that his conclusion is not true and the generalized second law is violated for the present time independently of the deceleration parameter.
Lauderdale, Jonathan M.
The effect of idealized wind-driven circulation changes in the Southern Ocean on atmospheric CO[subscript 2] and the ocean carbon inventory is investigated using a suite of coarse-resolution, global coupled ocean circulation ...
Khangaonkar, Tarang; Wang, Taiping
2013-01-02T23:59:59.000Z
Circulation in typical fjords is characterized by a shallow brackish layer at the surface over a deep long and narrow saltwater column. This surface layer is responsible for the outflow of water from the fjord, is easily disrupted by external forces, such as wind, and is influenced by freshwater inflow. In this paper, we postulate that the stability of fjordal circulation may also be vulnerable to impacts from anthropogenic alterations, such as floating structures, that could constrict the mixing and transport in the upper layers of the water column. The potential for alteration of circulation in Hood Canal, a silled-fjord located inside Puget Sound, Washington, has been examined. Using classical analytical treatments along the lines formulated by Hansen and Rattray [1965], Rattray [1967], Dyer [1973] and more recently, MacCready [2004], we develop a solution applicable to a range of estuary classifications varying from a partially mixed estuary regime to classical fjord conditions. Both estuary types exist in the Puget Sound system, and we compare our analytical solution with observed data. The analysis is based on an exponential variation of eddy viscosity with depth, and it has been extended further with modifications of the free surface boundary conditions to develop a solution representing the presence of a floating bridge at the estuary/fjord entrance. The model results show that tidally averaged mean circulation under the influence of such a constraint could reduce by as much as 30 to 50 percent. The overall water quality of fjords and narrow estuaries is dependent on net circulation and flushing. A potential decrease in residual flow or a corresponding increase in residence time of this magnitude merits further study.
The generalized Schrödinger–Langevin equation
Bargueño, Pedro, E-mail: p.bargueno@uniandes.edu.co [Departamento de Física, Universidad de los Andes, Apartado Aéreo 4976, Bogotá, Distrito Capital (Colombia); Miret-Artés, Salvador, E-mail: s.miret@iff.csic.es [Instituto de Física Fundamental, CSIC, Serrano 123, 28006, Madrid (Spain)
2014-07-15T23:59:59.000Z
In this work, for a Brownian particle interacting with a heat bath, we derive a generalization of the so-called Schrödinger–Langevin or Kostin equation. This generalization is based on a nonlinear interaction model providing a state-dependent dissipation process exhibiting multiplicative noise. Two straightforward applications to the measurement process are then analyzed, continuous and weak measurements in terms of the quantum Bohmian trajectory formalism. Finally, it is also shown that the generalized uncertainty principle, which appears in some approaches to quantum gravity, can be expressed in terms of this generalized equation. -- Highlights: •We generalize the Kostin equation for arbitrary system–bath coupling. •This generalization is developed both in the Schrödinger and Bohmian formalisms. •We write the generalized Kostin equation for two measurement problems. •We reformulate the generalized uncertainty principle in terms of this equation.
Scarlat, Raluca Olga
2012-01-01T23:59:59.000Z
geothermal reservoir. Greif provides a review of the use of applications of natural circulation to the cooling
Generalized concatenated quantum codes
Grassl, Markus
We discuss the concept of generalized concatenated quantum codes. This generalized concatenation method provides a systematical way for constructing good quantum codes, both stabilizer codes and nonadditive codes. Using ...
A General Relativistic Generalization of Bell Inequality
Vladan Pankovic
2005-06-16T23:59:59.000Z
In this work a general relativistic generalization of Bell inequality is suggested. Namely,it is proved that practically in any general relativistic metric there is a generalization of Bell inequality.It can be satisfied within theories of local (subluminal) hidden variables, but it cannot be satisfied in the general case within standard quantum mechanical formalism or within theories of nonlocal (superluminal) hidden variables. It is shown too that within theories of nonlocal hidden variables but not in the standard quantum mechanical formalism a paradox appears in the situation when one of the correlated subsystems arrives at a Schwarzschild black hole. Namely, there is no way that black hole horizon obstructs superluminal influences between spin of the subsystem without horizon and spin of the subsystem within horizon,or simply speaking,there is none black hole horizon nor "no hair" theorem for subsystems with correlated spins. It implies that standard quantum mechanical formalism yields unique consistent and complete description of the quantum mechanical phenomenons.
Vigil,Benny Manuel [Los Alamos National Laboratory; Ballance, Robert [SNL; Haskell, Karen [SNL
2012-08-09T23:59:59.000Z
Cielo is a massively parallel supercomputer funded by the DOE/NNSA Advanced Simulation and Computing (ASC) program, and operated by the Alliance for Computing at Extreme Scale (ACES), a partnership between Los Alamos National Laboratory (LANL) and Sandia National Laboratories (SNL). The primary Cielo compute platform is physically located at Los Alamos National Laboratory. This Cielo Computational Environment Usage Model documents the capabilities and the environment to be provided for the Q1 FY12 Level 2 Cielo Capability Computing (CCC) Platform Production Readiness Milestone. This document describes specific capabilities, tools, and procedures to support both local and remote users. The model is focused on the needs of the ASC user working in the secure computing environments at Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory, or Sandia National Laboratories, but also addresses the needs of users working in the unclassified environment. The Cielo Computational Environment Usage Model maps the provided capabilities to the tri-Lab ASC Computing Environment (ACE) Version 8.0 requirements. The ACE requirements reflect the high performance computing requirements for the Production Readiness Milestone user environment capabilities of the ASC community. A description of ACE requirements met, and those requirements that are not met, are included in each section of this document. The Cielo Computing Environment, along with the ACE mappings, has been issued and reviewed throughout the tri-Lab community.
Isomorphism testing for circulant graphs Cn(a, b)
2010-03-10T23:59:59.000Z
Mar 10, 2010 ... Page 1 ... and define a simple combinatorial model, which is new for the topic. Building on such a model, we derive a necessary and sufficient ...
MEASUREMENTS OF THE SUN'S HIGH-LATITUDE MERIDIONAL CIRCULATION
Rightmire-Upton, Lisa [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Hathaway, David H. [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Kosak, Katie, E-mail: lar0009@uah.edu, E-mail: david.hathaway@nasa.gov, E-mail: mkosak2011@my.fit.edu [Florida Institute of Technology, Melbourne, FL 32901 (United States)
2012-12-10T23:59:59.000Z
The meridional circulation at high latitudes is crucial to the buildup and reversal of the Sun's polar magnetic fields. Here, we characterize the axisymmetric flows by applying a magnetic feature cross-correlation procedure to high-resolution magnetograms obtained by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory. We focus on Carrington rotations 2096-2107 (2010 April to 2011 March)-the overlap interval between HMI and the Michelson Doppler Imager (MDI). HMI magnetograms averaged over 720 s are first mapped into heliographic coordinates. Strips from these maps are then cross-correlated to determine the distances in latitude and longitude that the magnetic element pattern has moved, thus providing meridional flow and differential rotation velocities for each rotation of the Sun. Flow velocities were averaged for the overlap interval and compared to results obtained from MDI data. This comparison indicates that these HMI images are rotated counterclockwise by 0.{sup 0}075 with respect to the Sun's rotation axis. The profiles indicate that HMI data can be used to reliably measure these axisymmetric flow velocities to at least within 5 Degree-Sign of the poles. Unlike the noisier MDI measurements, no evidence of a meridional flow counter-cell is seen in either hemisphere with the HMI measurements: poleward flow continues all the way to the poles. Slight north-south asymmetries are observed in the meridional flow. These asymmetries should contribute to the observed asymmetries in the polar fields and the timing of their reversals.
Puget Sound Dissolved Oxygen Modeling Study: Development of an Intermediate-Scale Hydrodynamic Model
Yang, Zhaoqing; Khangaonkar, Tarang; Labiosa, Rochelle G.; Kim, Taeyun
2010-11-30T23:59:59.000Z
The Washington State Department of Ecology contracted with Pacific Northwest National Laboratory to develop an intermediate-scale hydrodynamic and water quality model to study dissolved oxygen and nutrient dynamics in Puget Sound and to help define potential Puget Sound-wide nutrient management strategies and decisions. Specifically, the project is expected to help determine 1) if current and potential future nitrogen loadings from point and non-point sources are significantly impairing water quality at a large scale and 2) what level of nutrient reductions are necessary to reduce or dominate human impacts to dissolved oxygen levels in the sensitive areas. In this study, an intermediate-scale hydrodynamic model of Puget Sound was developed to simulate the hydrodynamics of Puget Sound and the Northwest Straits for the year 2006. The model was constructed using the unstructured Finite Volume Coastal Ocean Model. The overall model grid resolution within Puget Sound in its present configuration is about 880 m. The model was driven by tides, river inflows, and meteorological forcing (wind and net heat flux) and simulated tidal circulations, temperature, and salinity distributions in Puget Sound. The model was validated against observed data of water surface elevation, velocity, temperature, and salinity at various stations within the study domain. Model validation indicated that the model simulates tidal elevations and currents in Puget Sound well and reproduces the general patterns of the temperature and salinity distributions.
Evolution of Atlantic deep-water circulation: from the greenhouse to the icehouse
Via, Rachael Kathleen
2005-11-01T23:59:59.000Z
To better understand how the evolution of Cenozoic deep-water circulation related to changes in global climate and ocean basin configuration, we generated Nd isotope records from Ocean Drilling Program sites in the southeastern Atlantic to track...
Intermediate-depth circulation of the Indian and South Pacific Oceans measured by autonomous floats
Davis, Russ E
2005-01-01T23:59:59.000Z
circulation of the Pacific Ocean: Flow patterns, tracers,runs in the Indian and Pacific Oceans using the EstimatingIndian and (right) Pacific Oceans from the JPL–ECCO data-
Li, Xiaochang, S.M. Massachusetts Institute of Technology
2009-01-01T23:59:59.000Z
It is commonly accepted that media and communication technologies play pivotal roles in the complex processes of what is broadly termed "globalization." The increasing speed, volume, and scale of transnational circulation ...
The role of the geothermal heat flux in driving the abyssal ocean circulation
Mashayek, A.
The results presented in this paper demonstrate that the geothermal heat flux (GHF) from the solid Earth into the ocean plays a non-negligible role in determining both abyssal stratification and circulation strength. Based ...
The Full Water Disposal Ways and Study on Central Air-conditioning Circulation Cooling Water System
Zhang, J.
2006-01-01T23:59:59.000Z
This paper has been made the further study about the water quality issue of the central air-conditioning circulation cooling water. Based on the comparison of the existing common adopted disposal ways, put forward the new ways of combination...
Massingill, Robert Derryl, Jr.
2006-04-12T23:59:59.000Z
As the demand for oil and gas resources increases, the need to venture into more hostile environments becomes a dynamic focus in the petroleum industry. One problem associated with certain high risk formations is lost circulation. As a result...
Sensitivity of the Ocean's Meridional Overturning Circulation to Surface Conditions in the Paleogene
Haines, Brian Andrew
2012-10-19T23:59:59.000Z
Deep circulations in the ocean affect the distribution of physical, chemical, and biological properties, and are intimately entwined with the planetary-scale climate. Numerous proxies, including neodymium (Nd) in fossil fish teeth, point to a source...