National Library of Energy BETA

Sample records for wave travel time

  1. Recent developments in guided wave travel time tomography

    SciTech Connect (OSTI)

    Zon, Tim van; Volker, Arno

    2014-02-18

    The concept of predictive maintenance using permanent sensors that monitor the integrity of an installation is an interesting addition to the current method of periodic inspections. Guided wave tomography had been developed to create a map of the wall thickness using the travel times of guided waves. It can be used for both monitoring and for inspection of pipe-segments that are difficult to access, for instance at the location of pipe-supports. An important outcome of the tomography is the minimum remaining wall thickness, as this is critical in the scheduling of a replacement of the pipe-segment. In order to improve the sizing accuracy we have improved the tomography scheme. A number of major improvements have been realized allowing to extend the application envelope to pipes with a larger wall thickness and to larger distances between the transducer rings. Simulation results indicate that the sizing accuracy has improved and that is now possible to have a spacing of 8 meter between the source-ring and the receiver-ring. Additionally a reduction of the number of sensors required might be possible as well.

  2. Time domain analysis of a gyrotron traveling wave amplifier with misaligned electron beam

    SciTech Connect (OSTI)

    Wang, Qiushi Peng, Shuyuan; Luo, Jirun

    2014-08-15

    This article develops a time-domain theory to study the beam-wave interaction in gyrotron traveling wave amplifier (gyro-TWA) with a misaligned electron beam. The effects of beam misalignment on the TE{sub 01} mode gyro-TWA operating at the fundamental are discussed. Numerical results show that the effect of misalignment is less obvious when the input power is larger, and the influences of misalignment on the stable gain and the stable time are basically opposite.

  3. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, Vincent M.; Vawter, Gregory A.

    1993-01-01

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.

  4. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, V.M.; Vawter, G.A.

    1993-12-14

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size. 4 figures.

  5. Sequentially pulsed traveling wave accelerator

    DOE Patents [OSTI]

    Caporaso, George J.; Nelson, Scott D.; Poole, Brian R.

    2009-08-18

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  6. Topological horseshoes in travelling waves of discretized nonlinear wave equations

    SciTech Connect (OSTI)

    Chen, Yi-Chiuan; Chen, Shyan-Shiou; Yuan, Juan-Ming

    2014-04-15

    Applying the concept of anti-integrable limit to coupled map lattices originated from space-time discretized nonlinear wave equations, we show that there exist topological horseshoes in the phase space formed by the initial states of travelling wave solutions. In particular, the coupled map lattices display spatio-temporal chaos on the horseshoes.

  7. Traveling-wave device with mass flux suppression (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Traveling-wave device with mass flux suppression Title: Traveling-wave device with mass flux suppression A traveling-wave device is provided with the conventional moving pistons ...

  8. Investigation of structural heterogeneity at the SPE site using combined P–wave travel times and Rg phase velocities

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rowe, Charlotte A.; Patton, Howard J.

    2015-10-01

    Here, we present analyses of the 2D seismic structure beneath Source Physics Experiments (SPE) geophone lines that extended radially at 100 m spacing from 100 to 2000 m from the source borehole. With seismic sources at only one end of the geophone lines, standard refraction profiling methods cannot resolve seismic velocity structures unambiguously. In previous work, we demonstrated overall agreement between body-wave refraction modeling and Rg dispersion curves for the least complex of the five lines. A more detailed inspection supports a 2D reinterpretation of the structure. We obtained Rg phase velocity measurements in both the time and frequency domains,more » then used iterative adjustment of the initial 1D body-wave model to predict Rg dispersion curves to fit the observed values. Our method applied to the most topographically severe of the geophone lines is supplemented with a 2D ray-tracing approach, whose application to P-wave arrivals supports the Rg analysis. In addition, midline sources will allow us to refine our characterization in future work.« less

  9. TIMING OF SHOCK WAVES

    DOE Patents [OSTI]

    Tuck, J.L.

    1955-03-01

    This patent relates to means for ascertaining the instant of arrival of a shock wave in an exploslve charge and apparatus utilizing this means to coordinate the timing of two operations involving a short lnterval of time. A pair of spaced electrodes are inserted along the line of an explosive train with a voltage applied there-across which is insufficient to cause discharge. When it is desired to initiate operation of a device at the time the explosive shock wave reaches a particular point on the explosive line, the device having an inherent time delay, the electrodes are located ahead of the point such that the ionization of the area between the electrodes caused by the traveling explosive shock wave sends a signal to initiate operation of the device to cause it to operate at the proper time. The operated device may be photographic equipment consisting of an x-ray illuminating tube.

  10. Enabling time travel for the scholarly web

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

    Enabling time travel for the scholarly web Enabling time travel for the scholarly web An international team of information scientists has begun a study to investigate how web links ...

  11. Stable operating regime for traveling wave devices

    DOE Patents [OSTI]

    Carlsten, Bruce E.

    2000-01-01

    Autophase stability is provided for a traveling wave device (TWD) electron beam for amplifying an RF electromagnetic wave in walls defining a waveguide for said electromagnetic wave. An off-axis electron beam is generated at a selected energy and has an energy noise inherently arising from electron gun. The off-axis electron beam is introduced into the waveguide. The off-axis electron beam is introduced into the waveguide at a second radius. The waveguide structure is designed to obtain a selected detuning of the electron beam. The off-axis electron beam has a velocity and the second radius to place the electron beam at a selected distance from the walls defining the waveguide, wherein changes in a density of the electron beam due to the RF electromagnetic wave are independent of the energy of the electron beam to provide a concomitant stable operating regime relative to the energy noise.

  12. Code for Calculating Regional Seismic Travel Time

    Energy Science and Technology Software Center (OSTI)

    2009-07-10

    The RSTT software computes predictions of the travel time of seismic energy traveling from a source to a receiver through 2.5D models of the seismic velocity distribution within the Earth. The two primary applications for the RSTT library are tomographic inversion studies and seismic event location calculations. In tomographic inversions studies, a seismologist begins with number of source-receiver travel time observations and an initial starting model of the velocity distribution within the Earth. A forwardmore » travel time calculator, such as the RSTT library, is used to compute predictions of each observed travel time and all of the residuals (observed minus predicted travel time) are calculated. The Earth model is then modified in some systematic way with the goal of minimizing the residuals. The Earth model obtained in this way is assumed to be a better model than the starting model if it has lower residuals. The other major application for the RSTT library is seismic event location. Given an Earth model, an initial estimate of the location of a seismic event, and some number of observations of seismic travel time thought to have originated from that event, location codes systematically modify the estimate of the location of the event with the goal of minimizing the difference between the observed and predicted travel times. The second application, seismic event location, is routinely implemented by the military as part of its effort to monitor the Earth for nuclear tests conducted by foreign countries.« less

  13. Bifurcations of traveling wave solutions for an integrable equation

    SciTech Connect (OSTI)

    Li Jibin; Qiao Zhijun

    2010-04-15

    This paper deals with the following equation m{sub t}=(1/2)(1/m{sup k}){sub xxx}-(1/2)(1/m{sup k}){sub x}, which is proposed by Z. J. Qiao [J. Math. Phys. 48, 082701 (2007)] and Qiao and Liu [Chaos, Solitons Fractals 41, 587 (2009)]. By adopting the phase analysis method of planar dynamical systems and the theory of the singular traveling wave systems to the traveling wave solutions of the equation, it is shown that for different k, the equation may have infinitely many solitary wave solutions, periodic wave solutions, kink/antikink wave solutions, cusped solitary wave solutions, and breaking loop solutions. We discuss in a detail the cases of k=-2,-(1/2),(1/2),2, and parametric representations of all possible bounded traveling wave solutions are given in the different (c,g)-parameter regions.

  14. Geostatistical evaluation of travel time uncertainties

    SciTech Connect (OSTI)

    Devary, J.L.

    1983-08-01

    Data on potentiometric head and hydraulic conductivity, gathered from the Wolfcamp Formation of the Permian System, have exhibited tremendous spatial variability as a result of heterogeneities in the media and the presence of petroleum and natural gas deposits. Geostatistical data analysis and error propagation techniques (kriging and conditional simulation) were applied to determine the effect of potentiometric head uncertainties on radionuclide travel paths and travel times through the Wolfcamp Formation. Blok-average kriging was utilized to remove measurement error from potentiometric head data. The travel time calculations have been enhanced by the use of an inverse technique to determine the relative hydraulic conductivity along travel paths. In this way, the spatial variability of the hydraulic conductivity corresponding to streamline convergence and divergence may be included in the analysis. 22 references, 11 figures, 1 table.

  15. Dual variational principles for nonlinear traveling waves in multifluid plasmas

    SciTech Connect (OSTI)

    Webb, G. M.; McKenzie, J. F.; Mace, R. L.; Ko, C. M.; Zank, G. P.

    2007-08-15

    A Hamiltonian description of nonlinear, obliquely propagating traveling waves in a charge neutral, electron-proton, multifluid plasma is developed. The governing equations are written as a dual spatial Hamiltonian system. In the first formulation, the Hamiltonian is identified with the longitudinal, x-momentum flux integral P{sub x}=const, in which the energy integral {epsilon}={epsilon}{sub 0} acts as a constraint, and the Hamiltonian evolution operator is d/dx, where x is the position coordinate in the wave frame. In the second Hamiltonian formulation, the Hamiltonian is proportional to the conserved energy integral {epsilon}, in which the momentum integral P{sub x}=const acts as a constraint, and the Hamiltonian evolution operator d/d{tau}=u{sub x}d/dx is the Lagrangian time derivative where u{sub x} is the x component of the electron and proton fluids. The analysis is facilitated by using the de Hoffman-Teller frame of magnetohydrodynamic shock theory to simplify the transverse electron and proton momentum equations. The system is exactly integrable in cases in which the total transverse momentum fluxes of the system are zero in the de Hoffman-Teller frame. The implications of this constraint for the Alfven Mach number of the traveling wave are discussed. The physical conditions for the formation of whistler oscillitons based on the whistler dispersion equation are discussed.

  16. Traveling wave device for combining or splitting symmetric and asymmetric waves

    DOE Patents [OSTI]

    Möbius, Arnold; Ives, Robert Lawrence

    2005-07-19

    A traveling wave device for the combining or splitting of symmetric and asymmetric traveling wave energy includes a feed waveguide for traveling wave energy, the feed waveguide having an input port and a launching port, a reflector for coupling wave energy between the feed waveguide and a final waveguide for the collection and transport of wave energy to or from the reflector. The power combiner has a launching port for symmetrical waves which includes a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which includes a sawtooth rotated about a central axis.

  17. Supplemental Guidance Regarding Compensatory Time Off for Travel |

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

    Department of Energy Supplemental Guidance Regarding Compensatory Time Off for Travel Supplemental Guidance Regarding Compensatory Time Off for Travel Questions and answers on issues that supplement the final regulations on compensatory time for travel issued by the Office of Personnel Management. In addition, a sample worksheet is attached to assist travelers in determining and documenting their travel time that may be credited for compensatory time for travel. This information will be

  18. Traveling-wave device with mass flux suppression

    DOE Patents [OSTI]

    Swift, Gregory W.; Backhaus, Scott N.; Gardner, David L.

    2000-01-01

    A traveling-wave device is provided with the conventional moving pistons eliminated. Acoustic energy circulates in a direction through a fluid within a torus. A side branch may be connected to the torus for transferring acoustic energy into or out of the torus. A regenerator is located in the torus with a first heat exchanger located on a first side of the regenerator downstream of the regenerator relative to the direction of the circulating acoustic energy; and a second heat exchanger located on an upstream side of the regenerator. The improvement is a mass flux suppressor located in the torus to minimize time-averaged mass flux of the fluid. In one embodiment, the device further includes a thermal buffer column in the torus to thermally isolate the heat exchanger that is at the operating temperature of the device.

  19. Investigation of structural heterogeneity at the SPE site using combined Pwave travel times and Rg phase velocities

    SciTech Connect (OSTI)

    Rowe, Charlotte A.; Patton, Howard J.

    2015-10-01

    Here, we present analyses of the 2D seismic structure beneath Source Physics Experiments (SPE) geophone lines that extended radially at 100 m spacing from 100 to 2000 m from the source borehole. With seismic sources at only one end of the geophone lines, standard refraction profiling methods cannot resolve seismic velocity structures unambiguously. In previous work, we demonstrated overall agreement between body-wave refraction modeling and Rg dispersion curves for the least complex of the five lines. A more detailed inspection supports a 2D reinterpretation of the structure. We obtained Rg phase velocity measurements in both the time and frequency domains, then used iterative adjustment of the initial 1D body-wave model to predict Rg dispersion curves to fit the observed values. Our method applied to the most topographically severe of the geophone lines is supplemented with a 2D ray-tracing approach, whose application to P-wave arrivals supports the Rg analysis. In addition, midline sources will allow us to refine our characterization in future work.

  20. Tuning gain and bandwidth of traveling wave tubes using metamaterial beam-wave interaction structures

    SciTech Connect (OSTI)

    Lipton, Robert Polizzi, Anthony

    2014-10-14

    We employ metamaterial beam-wave interaction structures for tuning the gain and bandwidth of short traveling wave tubes. The interaction structures are made from metal rings of uniform cross section, which are periodically deployed along the length of the traveling wave tube. The aspect ratio of the ring cross sections is adjusted to control both gain and bandwidth. The frequency of operation is controlled by the filling fraction of the ring cross section with respect to the size of the period cell.

  1. Apparatus and method for measuring and imaging traveling waves

    DOE Patents [OSTI]

    Telschow, Kenneth L.; Deason, Vance A.

    2001-01-01

    An apparatus is provided for imaging traveling waves in a medium. The apparatus includes a vibration excitation source configured to impart traveling waves within a medium. An emitter is configured to produce two or more wavefronts, at least one wavefront modulated by a vibrating medium. A modulator is configured to modulate another wavefront in synchronization with the vibrating medium. A sensing media is configured to receive in combination the modulated one wavefront and the another wavefront and having a detection resolution within a limited bandwidth. The another wavefront is modulated at a frequency such that a difference frequency between the one wavefront and the another wavefront is within a response range of the sensing media. Such modulation produces an image of the vibrating medium having an output intensity that is substantially linear with small physical variations within the vibrating medium for all vibration frequencies above the sensing media's response bandwidth. A detector is configured to detect an image of traveling waves in the vibrating medium resulting from interference between the modulated one wavefront and the another wavefront when combined in association with the sensing media. The traveling wave can be used to characterize certain material properties of the medium. Furthermore, a method is provided for imaging and characterizing material properties according to the apparatus.

  2. Shielded serpentine traveling wave tube deflection structure

    DOE Patents [OSTI]

    Hudson, C.L.; Spector, J.

    1994-12-27

    A shielded serpentine slow wave deflection structure is disclosed having a serpentine signal conductor within a channel groove. The channel groove is formed by a serpentine channel in a trough plate and a ground plane. The serpentine signal conductor is supported at its ends by coaxial feed through connectors. A beam interaction trough intersects the channel groove to form a plurality of beam interaction regions wherein an electron beam may be deflected relative to the serpentine signal conductor. 4 figures.

  3. Shielded serpentine traveling wave tube deflection structure

    DOE Patents [OSTI]

    Hudson, Charles L.; Spector, Jerome

    1994-01-01

    A shielded serpentine slow wave deflection structure (10) having a serpene signal conductor (12) within a channel groove (46). The channel groove (46) is formed by a serpentine channel (20) in a trough plate (18) and a ground plane (14). The serpentine signal conductor (12) is supported at its ends by coaxial feed through connectors 28. A beam interaction trough (22) intersects the channel groove (46) to form a plurality of beam interaction regions (56) wherein an electron beam (54) may be deflected relative to the serpentine signal conductor (12).

  4. Traveling waves and their tails in locally resonant granular systems

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, H.; Kevrekidis, P. G.; Stefanov, A.

    2015-04-22

    In the present study, we revisit the theme of wave propagation in locally resonant granular crystal systems, also referred to as mass-in-mass systems. We use three distinct approaches to identify relevant traveling waves. In addition, the first consists of a direct solution of the traveling wave problem. The second one consists of the solution of the Fourier tranformed variant of the problem, or, more precisely, of its convolution reformulation (upon an inverse Fourier transform) in real space. Finally, our third approach will restrict considerations to a finite domain, utilizing the notion of Fourier series for important technical reasons, namely themore » avoidance of resonances, which will be discussed in detail. All three approaches can be utilized in either the displacement or the strain formulation. Typical resulting computations in finite domains result in the solitary waves bearing symmetric non-vanishing tails at both ends of the computational domain. Importantly, however, a countably infinite set of anti-resonance conditions is identified for which solutions with genuinely rapidly decaying tails arise.« less

  5. Design and fabrication of a traveling-wave muffin-tin accelerating structure at 90 GHz

    SciTech Connect (OSTI)

    Chou, P.J.; Bowden, G.B.; Copeland, M.R.; Menegat, A.; Siemann, R.H.; Henke, H.

    1997-05-01

    A prototype of a muffin-tin accelerating structure operating at 32 times the SLAC frequency (2.856 GHz) was built for research in high gradient acceleration. A traveling-wave design with single input and output feeds was chosen for the prototype which was fabricated by wire electrodischarge machining. Features of the mechanical design for the prototype are described. Design improvements are presented including considerations of cooling and vacuum.

  6. Three-cell traveling wave superconducting test structure

    SciTech Connect (OSTI)

    Avrakhov, Pavel; Kanareykin, Alexei; /Euclid Techlabs, Solon; Kazakov, Sergey; Solyak, Nikolay; Wu, Genfa; Yakovlev, Vyacheslav P.; /Fermilab

    2011-03-01

    Use of a superconducting traveling wave accelerating (STWA) structure with a small phase advance per cell rather than a standing wave structure may provide a significant increase of the accelerating gradient in the ILC linac. For the same surface electric and magnetic fields the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing wave cavities. The STWA allows also longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed, manufactured and successfully tested demonstrating the possibility of a proper processing to achieve a high accelerating gradient. These results open way to take the next step of the TW SC cavity development: to build and test a travelingwave three-cell cavity with a feedback waveguide. The latest results of the single-cell cavity tests are discussed as well as the design of the test 3-cell TW cavity.

  7. Wave coupling in sheet- and multiple-beam traveling-wave tubes

    SciTech Connect (OSTI)

    Nusinovich, Gregory S.; Cooke, Simon J.; Levush, Baruch; Botton, Moti

    2009-06-15

    To increase the power level of the sources of coherent electromagnetic radiation at frequencies from 100 GHz up to the terahertz range it makes sense to develop devices with a spatially extended interaction space. Sheet-beam and multiple-beam devices belong to the category. In the present paper the small-signal theory of traveling-wave tubes with sheet-beam and multiple sheet-beam configurations is developed. It is shown that in such tubes the wave coupling on electron beams may occur even in small-signal regimes. The wave coupling and its role for amplification of forward and excitation of backward waves in such amplifiers is studied. Also the effect of transverse nonuniformity of the electromagnetic field on the device operation is analyzed and illustrated by several examples.

  8. Modeling highway travel time distribution with conditional probability models

    SciTech Connect (OSTI)

    Oliveira Neto, Francisco Moraes; Chin, Shih-Miao; Hwang, Ho-Ling; Han, Lee

    2014-01-01

    ABSTRACT Under the sponsorship of the Federal Highway Administration's Office of Freight Management and Operations, the American Transportation Research Institute (ATRI) has developed performance measures through the Freight Performance Measures (FPM) initiative. Under this program, travel speed information is derived from data collected using wireless based global positioning systems. These telemetric data systems are subscribed and used by trucking industry as an operations management tool. More than one telemetric operator submits their data dumps to ATRI on a regular basis. Each data transmission contains truck location, its travel time, and a clock time/date stamp. Data from the FPM program provides a unique opportunity for studying the upstream-downstream speed distributions at different locations, as well as different time of the day and day of the week. This research is focused on the stochastic nature of successive link travel speed data on the continental United States Interstates network. Specifically, a method to estimate route probability distributions of travel time is proposed. This method uses the concepts of convolution of probability distributions and bivariate, link-to-link, conditional probability to estimate the expected distributions for the route travel time. Major contribution of this study is the consideration of speed correlation between upstream and downstream contiguous Interstate segments through conditional probability. The established conditional probability distributions, between successive segments, can be used to provide travel time reliability measures. This study also suggests an adaptive method for calculating and updating route travel time distribution as new data or information is added. This methodology can be useful to estimate performance measures as required by the recent Moving Ahead for Progress in the 21st Century Act (MAP 21).

  9. Flow calculations for Yucca Mountain groundwater travel time (GWTT-95)

    SciTech Connect (OSTI)

    Altman, S.J.; Arnold, B.W.; Barnard, R.W.; Barr, G.E.; Ho, C.K.; McKenna, S.A.; Eaton, R.R.

    1996-09-01

    In 1983, high-level radioactive waste repository performance requirements related to groundwater travel time were defined by NRC subsystem regulation 10 CFR 60.113. Although DOE is not presently attempting to demonstrate compliance with that regulation, understanding of the prevalence of fast paths in the groundwater flow system remains a critical element of any safety analyses for a potential repository system at Yucca Mountain, Nevada. Therefore, this analysis was performed to allow comparison of fast-path flow against the criteria set forth in the regulation. Models developed to describe the conditions for initiation, propagation, and sustainability of rapid groundwater movement in both the unsaturated and saturated zones will form part of the technical basis for total- system analyses to assess site viability and site licensability. One of the most significant findings is that the fastest travel times in both unsaturated and saturated zones are in the southern portion of the potential repository, so it is recommended that site characterization studies concentrate on this area. Results support the assumptions regarding the importance of an appropriate conceptual model of groundwater flow and the incorporation of heterogeneous material properties into the analyses. Groundwater travel times are sensitive to variation/uncertainty in hydrologic parameters and in infiltration flux at upper boundary of the problem domain. Simulated travel times are also sensitive to poorly constrained parameters of the interaction between flow in fractures and in the matrix.

  10. SENSITIVITY OF HELIOSEISMIC TRAVEL TIMES TO THE IMPOSITION OF A LORENTZ FORCE LIMITER IN COMPUTATIONAL HELIOSEISMOLOGY

    SciTech Connect (OSTI)

    Moradi, Hamed; Cally, Paul S.

    2014-02-20

    The rapid exponential increase in the Alfvn wave speed with height above the solar surface presents a serious challenge to physical modeling of the effects of magnetic fields on solar oscillations, as it introduces a significant Courant-Friedrichs-Lewy time-step constraint for explicit numerical codes. A common approach adopted in computational helioseismology, where long simulations in excess of 10 hr (hundreds of wave periods) are often required, is to cap the Alfvn wave speed by artificially modifying the momentum equation when the ratio between the Lorentz and hydrodynamic forces becomes too large. However, recent studies have demonstrated that the Alfvn wave speed plays a critical role in the MHD mode conversion process, particularly in determining the reflection height of the upwardly propagating helioseismic fast wave. Using numerical simulations of helioseismic wave propagation in constant inclined (relative to the vertical) magnetic fields we demonstrate that the imposition of such artificial limiters significantly affects time-distance travel times unless the Alfvn wave-speed cap is chosen comfortably in excess of the horizontal phase speeds under investigation.

  11. Mechanisms of amplification of ultrashort electromagnetic pulses in gyrotron traveling wave tube with helically corrugated waveguide

    SciTech Connect (OSTI)

    Ginzburg, N. S. Zaslavsky, V. Yu.; Zotova, I. V.; Sergeev, A. S.; Zheleznov, I. V.; Samsonov, S. V.; Mishakin, S. V.

    2015-11-15

    A time-domain self consistent theory of a gyrotron traveling wave tube with a helically corrugated operating waveguide has been developed. Based on this model, the process of short pulse amplification was studied in regimes of grazing and intersection of the dispersion curves of the electromagnetic wave and the electron beam. In the first case, the possibility of amplification without pulse form distortion was demonstrated for the pulse spectrum width of the order of the gain bandwidth. In the second case, when the electrons' axial velocity was smaller than the wave's group velocity, it was shown that the slippage of the incident signal with respect to the electron beam provides feeding of the signal by “fresh” electrons without initial modulation. As a result, the amplitude of the output pulse can exceed the amplitude of its saturated value for the case of the grazing regime, and, for optimal parameters, the peak output power can be even larger than the kinetic power of the electron beam.

  12. Traveling wave solutions in a chain of periodically forced coupled nonlinear oscillators

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Duanmu, M.; Whitaker, N.; Kevrekidis, P. G.; Vainchtein, A.; Rubin, J. E.

    2016-02-27

    Artificial perceptions of light called phosphenes were motivated by earlier studies. We analyze traveling wave solutions in a chain of periodically forced coupled nonlinear oscillators modeling this phenomenon. We examine the discrete model problem in its co-traveling frame and systematically obtain the corresponding traveling waves in one spatial dimension. Direct numerical simulations as well as linear stability analysis are employed to reveal the parameter regions where the traveling waves are stable, and these waves are, in turn, connected to the standing waves analyzed in earlier work. We also consider a two-dimensional extension of the model and demonstrate the robust evolutionmore » and stability of planar fronts. Moreover, our simulations also suggest the radial fronts tend to either annihilate or expand and flatten out, depending on the phase value inside and the parameter regime. Finally, we observe that solutions that initially feature two symmetric fronts with bulged centers evolve in qualitative agreement with experimental observations of phosphenes.« less

  13. Comparison of actinide production in traveling wave and pressurized water reactors

    SciTech Connect (OSTI)

    Osborne, A.G.; Smith, T.A.; Deinert, M.R.

    2013-07-01

    The geopolitical problems associated with civilian nuclear energy production arise in part from the accumulation of transuranics in spent nuclear fuel. A traveling wave reactor is a type of breed-burn reactor that could, if feasible, reduce the overall production of transuranics. In one possible configuration, a cylinder of natural or depleted uranium would be subjected to a fast neutron flux at one end. The neutrons would transmute the uranium, producing plutonium and higher actinides. Under the right conditions, the reactor could become critical, at which point a self-stabilizing fission wave would form and propagate down the length of the reactor cylinder. The neutrons from the fission wave would burn the fissile nuclides and transmute uranium ahead of the wave to produce additional fuel. Fission waves in uranium are driven largely by the production and fission of {sup 239}Pu. Simulations have shown that the fuel burnup can reach values greater than 400 MWd/kgIHM, before fission products poison the reaction. In this work we compare the production of plutonium and minor actinides produced in a fission wave to that of a UOX fueled light water reactor, both on an energy normalized basis. The nuclide concentrations in the spent traveling wave reactor fuel are computed using a one-group diffusion model and are verified using Monte Carlo simulations. In the case of the pressurized water reactor, a multi-group collision probability model is used to generate the nuclide quantities. We find that the traveling wave reactor produces about 0.187 g/MWd/kgIHM of transuranics compared to 0.413 g/MWd/kgIHM for a pressurized water reactor running fuel enriched to 4.95 % and burned to 50 MWd/kgIHM. (authors)

  14. X-BAND TRAVELING WAVE RF DEFLECTOR STRUCTURES

    SciTech Connect (OSTI)

    Wang, J.W.; Tantawi, S.; /SLAC

    2008-12-18

    Design studies on the X-Band transverse RF deflectors operating at HEM{sub ll} mode have been made for two different applications. One is for beam measurement of time-sliced emittance and slice energy spread for the upgraded LCLS project, its optimization in RF efficiency and system design are carefully considered. Another is to design an ultra-fast RF kicker in order to pick up single bunches from the bunch-train of the B-factory storage ring. The challenges are to obtain very short structure filling time with high RF group velocity and good RF efficiency with reasonable transverse shunt impedance. Its RF system will be discussed.

  15. Shielded helix traveling wave cathode ray tube deflection structure

    DOE Patents [OSTI]

    Norris, Neil J.; Hudson, Charles L.

    1992-01-01

    Various embodiments of a helical coil deflection structure of a CRT are described and illustrated which provide shielding between adjacent turns of the coil on either three or four sides of each turn in the coil. Threaded members formed with either male or female threads and having the same pitch as the deflection coil are utilized for shielding the deflection coil with each turn of the helical coil placed between adjacent threads which act to shield each coil turn from adjacent turns and to confine the field generated by the coil to prevent or inhibit cross-coupling between adjacent turns of the coil to thereby prevent generation of fast fields which might otherwise deflect the beam out of time synchronization with the electron beam pulse.

  16. Shielded helix traveling wave cathode ray tube deflection structure

    DOE Patents [OSTI]

    Norris, N.J.; Hudson, C.L.

    1992-12-15

    Various embodiments of a helical coil deflection structure of a CRT are described and illustrated which provide shielding between adjacent turns of the coil on either three or four sides of each turn in the coil. Threaded members formed with either male or female threads and having the same pitch as the deflection coil are utilized for shielding the deflection coil with each turn of the helical coil placed between adjacent threads which act to shield each coil turn from adjacent turns and to confine the field generated by the coil to prevent or inhibit cross-coupling between adjacent turns of the coil to thereby prevent generation of fast fields which might otherwise deflect the beam out of time synchronization with the electron beam pulse. 13 figs.

  17. One-dimensional kinetic description of nonlinear traveling-pulse and traveling-wave disturbances in long coasting charged particle beams

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Davidson, Ronald C.; Qin, Hong

    2015-09-21

    This paper makes use of a one-dimensional kinetic model to investigate the nonlinear longitudinal dynamics of a long coasting beam propagating through a perfectly conducting circular pipe with radius r w . The average axial electric field is expressed as z >=(?/?z)=ebg???b/?z ebg2r2w?3?b/?z3, where g0 and g2 are constant geometric factors, ?b(z,t)=?dpz Fb (z,pz,t) is the line density of beam particles, and F b (z,pz,t) satisfies the 1D Vlasov equation. Detailed nonlinear properties of traveling-wave and traveling-pulse (soliton) solutions with time-stationary waveform are examined for a wide range of system parameters extending from moderate-amplitudes to large-amplitude modulations ofmorethe beam charge density. Two classes of solutions for the beam distribution function are considered, corresponding to: (i) the nonlinear waterbag distribution, where Fb = const in a bounded region of pz-space; and (ii) nonlinear Bernstein-Green-Kruskal (BGK)-like solutions, allowing for both trapped and untrapped particle distributions to interact with the self-generated electric field.less

  18. Verification of the helioseismology travel-time measurement technique and the inversion procedure for sound speed using artificial data

    SciTech Connect (OSTI)

    Parchevsky, K. V.; Zhao, J.; Hartlep, T.; Kosovichev, A. G.

    2014-04-10

    We performed three-dimensional numerical simulations of the solar surface acoustic wave field for the quiet Sun and for three models with different localized sound-speed perturbations in the interior with deep, shallow, and two-layer structures. We used the simulated data generated by two solar acoustics codes that employ the same standard solar model as a background model, but utilize different integration techniques and different models of stochastic wave excitation. Acoustic travel times were measured using a time-distance helioseismology technique, and compared with predictions from ray theory frequently used for helioseismic travel-time inversions. It is found that the measured travel-time shifts agree well with the helioseismic theory for sound-speed perturbations, and for the measurement procedure with and without phase-speed filtering of the oscillation signals. This testing verifies the whole measuring-filtering-inversion procedure for static sound-speed anomalies with small amplitude inside the Sun outside regions of strong magnetic field. It is shown that the phase-speed filtering, frequently used to extract specific wave packets and improve the signal-to-noise ratio, does not introduce significant systematic errors. Results of the sound-speed inversion procedure show good agreement with the perturbation models in all cases. Due to its smoothing nature, the inversion procedure may overestimate sound-speed variations in regions with sharp gradients of the sound-speed profile.

  19. Simulation studies on the standing and traveling wave thermoacoustic prime movers

    SciTech Connect (OSTI)

    Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.; Kasthurirengan, S.; Behera, Upendra

    2014-01-29

    Thermoacoustic systems have been a focus of recent research due to its structural simplicity, high reliability due to absence of moving parts, and can be driven by low grade energy such as fuel, gas, solar energy, waste heat etc. There has been extensive research on both standing wave and traveling wave systems. Towards the development of such systems, simulations can be carried out by several methods such as (a) solving the energy equation, (b) enthalpy flow model, (c) DeltaEC, a free software available from LANL, USA (d) Computational Fluid Dynamics (CFD) etc. We present here the simulation studies of standing wave and traveling wave thermoacoustic prime movers using CFD and DeltaEC. The CFD analysis is carried out using Fluent 6.3.26, incorporating the necessary boundary conditions with different working fluids at different operating pressures. The results obtained by CFD are compared with those obtained using DeltaEC. Also, the CFD simulation of the thermoacoustically driven refrigerator is presented.

  20. Traveling waves for the mass in mass model of granular chains

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kevrekidis, Panayotis G.; Stefanov, Atanas G.; Xu, Haitao

    2016-08-01

    In this work, we consider the mass in mass (or mass with mass) system of granular chains, namely, a granular chain involving additionally an internal (or, respectively, external) resonator. For these chains, we rigorously establish that under suitable “anti-resonance” conditions connecting the mass of the resonator and the speed of the wave, bell-shaped traveling-wave solutions continue to exist in the system, in a way reminiscent of the results proven for the standard granular chain of elastic Hertzian contacts. Finally, we also numerically touch upon settings, where the conditions do not hold, illustrating, in line also with recent experimental work, thatmore » non-monotonic waves bearing non-vanishing tails may exist in the latter case.« less

  1. Integrating a Traveling Wave Tube into an AECR-U ion source

    SciTech Connect (OSTI)

    Covo, Michel Kireeff; Benitez, Janilee Y.; Ratti, Alessandro; Vujic, Jasmina L.

    2011-07-01

    An RF system of 500W - 10.75 to 12.75 GHz was designed and integrated into the Advanced Electron Cyclotron Resonance - Upgrade (AECR-U) ion source of the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The AECR-U produces ion beams for the Cyclotron giving large flexibility of ion species and charge states. The broadband frequency of a Traveling Wave Tube (TWT) allows modifying the volume that couples and heats the plasma. The TWT system design and integration with the AECR-U ion source and results from commissioning are presented.

  2. Enhanced traveling wave amplification of co-planar slow wave structure by extended phase-matching

    SciTech Connect (OSTI)

    Palm, Andrew; Sirigiri, Jagadishwar; Shin, Young-Min

    2015-09-15

    The electron beam co-propagating with slow waves in a staggered double grating array (SDGA) efficiently amplifies millimeter and sub-millimeter waves over a wide spectrum. Our theoretical and numerical analyses show that the power amplification in the fundamental passband is enhanced by the extended beam-wave phase-matching. Particle-in-cell simulations on the SDGA slow wave structure, designed with 10.4 keV and 50–100 mA sheet beam, indicate that maintaining beam-wave synchronization along the entire length of the circuit improves the gain by 7.3% leading to a total gain of 28 dB, corresponding to 62 W saturated power at the middle of operating band, and a 3-dB bandwidth of 7 GHz with 10.5% at V-band (73.5 GHz center frequency) with saturated peak power reaching 80 W and 28 dB at 71 GHz. These results also show a reasonably good agreement with analytic calculations based on Pierce small signal gain theory.

  3. Characterization of Traveling Wave Ion Mobility Separations in Structures for Lossless Ion Manipulations

    SciTech Connect (OSTI)

    Hamid, Ahmed M.; Ibrahim, Yehia M.; Garimella, Venkata BS; Webb, Ian K.; Deng, Liulin; Chen, Tsung-Chi; Anderson, Gordon A.; Prost, Spencer A.; Norheim, Randolph V.; Tolmachev, Aleksey V.; Smith, Richard D.

    2015-10-28

    We report on the development and characterization of a new traveling wave-based Structure for Lossless Ion Manipulations (TW-SLIM) for ion mobility separations (IMS). The TW-SLIM module uses a parallel array of RF electrodes for ion confinement, spaced by an array of short DC electrodes to which a TW can be applied to drive ion motion. The ability of the TW-SLIM for efficient ion confinement, lossless ion transport, and ion mobility separations at different RF and TW parameters is reported. The TW-SLIM module is shown to allow transfers a wide mass range of ions (200-2500 Da) utilizing a confining RF waveform (1 MHz and 300 Vp-p), and low TW amplitudes (<20 V). Also, the short module achieved an ion mobility peak capacity of 24 and a peak generation rate of 1014 s-1 for TW speeds of <210 m/s. TW-SLIM performance was characterized over a wide range of RF and DC voltage parameters, and demonstrated robust performance. The combined attributes of flexible design and low voltage requirements for traveling wave IMS, provide a basis for SLIM devices incorporating extended series of ion manipulations.

  4. A nonlinear analysis of the terahertz serpentine waveguide traveling-wave amplifier

    SciTech Connect (OSTI)

    Li, Ke Cao, Miaomiao; Liu, Wenxin Wang, Yong

    2015-04-15

    A nonlinear model for the numerical simulation of terahertz serpentine waveguide traveling-wave tube (SW-TWT) is described. In this model, the electromagnetic wave transmission in the SW is represented as an infinite set of space harmonics to interact with an electron beam. Analytical expressions for axial electric fields in axisymmetric interaction gaps of SW-TWTs are derived and compared with the results from CST simulation. The continuous beam is treated as discrete macro-particles with different initial phases. The beam-tunnel field equations, space-charge field equations, and motion equations are combined to solve the beam-wave interaction. The influence of backward wave and relativistic effect is also considered in the series of equations. The nonlinear model is used to design a 340 GHz SW-TWT. Several favorable comparisons of model predictions with results from a 3-D Particle-in-cell simulation code CHIPIC are presented, in which the output power versus beam voltage and interaction periods are illustrated. The relative error of the predicted output power is less than 15% in the 3 dB bandwidth and the relative error of the saturated length is less than 8%.The results show that the 1-D nonlinear analysis model is appropriate to solve the terahertz SW-TWT operation characteristics.

  5. G-band harmonic multiplying gyrotron traveling-wave amplifier with a mode-selective circuit

    SciTech Connect (OSTI)

    Yeh, Y. S.; Chen, Chang-Hong; Wang, Z. W.; Kao, B. H.; Chen, Chien-Hsiang; Lin, T. Y.; Guo, Y. W.

    2014-12-15

    Harmonic multiplying gyrotron traveling-wave amplifiers (gyro-TWAs) permit for magnetic field reduction and frequency multiplication. A high-order-mode harmonic multiplying gyro-TWA with large circuit dimensions and low ohmic loss can achieve a high average power. By amplifying a fundamental harmonic TE{sub 01} drive wave, the second harmonic component of the beam current initiates a TE{sub 02} wave to be amplified. Wall losses can suppress some competing modes because they act as an effective sink of the energy of the modes. However, such wall losses do not suppress all competing modes as the fields are contracted in the copper section in the gyro-TWA. An improved mode-selective circuit, using circular waveguides with the specified radii, can provide the rejection points within the frequency range to suppress the competing modes. The simulated results reveal that the mode-selective circuit can provide an attenuation of more than 10 dB to suppress the competing modes (TE{sub 21}, TE{sub 51}, TE{sub 22}, and TE{sub 03}). A G-band second harmonic multiplying gyro-TWA with the mode-selective circuit is predicted to yield a peak output power of 50 kW at 198.8 GHz, corresponding to a saturated gain of 55 dB at an interaction efficiency of 10%. The full width at half maximum bandwidth is 5 GHz.

  6. Traveling wave parametric amplifier with Josephson junctions using minimal resonator phase matching

    SciTech Connect (OSTI)

    White, T. C.; Mutus, J. Y.; Hoi, I.-C.; Barends, R.; Campbell, B.; Chen, Yu; Chen, Z.; Chiaro, B.; Dunsworth, A.; Jeffrey, E.; Kelly, J.; Neill, C.; O'Malley, P. J. J.; Roushan, P.; Sank, D.; Vainsencher, A.; Wenner, J.; Martinis, John M.; Megrant, A.; Chaudhuri, S.; and others

    2015-06-15

    Josephson parametric amplifiers have become a critical tool in superconducting device physics due to their high gain and quantum-limited noise. Traveling wave parametric amplifiers (TWPAs) promise similar noise performance, while allowing for significant increases in both bandwidth and dynamic range. We present a TWPA device based on an LC-ladder transmission line of Josephson junctions and parallel plate capacitors using low-loss amorphous silicon dielectric. Crucially, we have inserted ?/4 resonators at regular intervals along the transmission line in order to maintain the phase matching condition between pump, signal, and idler and increase gain. We achieve an average gain of 12?dB across a 4?GHz span, along with an average saturation power of ?92 dBm with noise approaching the quantum limit.

  7. Preliminary performance of the MKII 17 GHz traveling wave relativistic klystron

    SciTech Connect (OSTI)

    Haimson, J.; Mecklenburg, B.; Stowell, G.; Kreischer, K. E.; Mastovsky, I. [Haimson Research Corporation, 3350 Scott Blvd., Building 60, Santa Clara, California 95054-3104 (United States); Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4294 (United States)

    1999-05-07

    Initial test results are presented of an upgraded RF source developed for high peak power 17 GHz linear accelerator applications. The objectives of this upgrade program were (a) to increase the output capability of the existing vacuum demountable prototype tube so that RF power could also be supplied to a future 2 MeV photoinjector system without appreciable loss of input power to the 17 GHz linac and (b) to investigate the performance of a new design traveling wave output circuit incorporating a racetrack shaped dual output coupler with 5% bandwidth high peak power ceramic RF windows. These recently installed devices are presently being conditioned and tested at the MIT Plasma Science and Fusion Center.

  8. Preliminary performance of the MKII 17 GHz traveling wave relativistic klystron

    SciTech Connect (OSTI)

    Haimson, J.; Mecklenburg, B.; Stowell, G. [Haimson Research Corporation, 3350 Scott Blvd., Building 60, Santa Clara, California 95054-3104 (United States); Kreischer, K.E.; Mastovsky, I. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4294 (United States)

    1999-05-01

    Initial test results are presented of an upgraded RF source developed for high peak power 17 GHz linear accelerator applications. The objectives of this upgrade program were (a) to increase the output capability of the existing vacuum demountable prototype tube so that RF power could also be supplied to a future 2 MeV photoinjector system without appreciable loss of input power to the 17 GHz linac and (b) to investigate the performance of a new design traveling wave output circuit incorporating a racetrack shaped dual output coupler with 5{percent} bandwidth high peak power ceramic RF windows. These recently installed devices are presently being conditioned and tested at the MIT Plasma Science and Fusion Center. {copyright} {ital 1999 American Institute of Physics.}

  9. Quantifying groundwater travel time near managed recharge operations using 35S as an intrinsic tracer

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Urióstegui, Stephanie H.; Bibby, Richard K.; Esser, Bradley K.; Clark, Jordan F.

    2016-04-23

    By identifying groundwater retention times near managed aquifer recharge (MAR) facilities is a high priority for managing water quality, especially for operations that incorporate recycled wastewater. In order to protect public health, California guidelines for Groundwater Replenishment Reuse Projects require a minimum 2–6 month subsurface retention time for recycled water depending on the level of disinfection, which highlights the importance of quantifying groundwater travel times on short time scales. This study developed and evaluated a new intrinsic tracer method using the naturally occurring radioisotope sulfur-35 (35S). The 87.5 day half-life of 35S is ideal for investigating groundwater travel times onmore » the <1 year timescale of interest to MAR managers. Natural concentrations of 35S found in water as dissolved sulfate (35SO4) were measured in source waters and groundwater at the Rio Hondo Spreading Grounds in Los Angeles County, CA, and Orange County Groundwater Recharge Facilities in Orange County, CA. 35SO4 travel times are comparable to travel times determined by well-established deliberate tracer studies. The study also revealed that 35SO4 in MAR source water can vary seasonally and therefore careful characterization of 35SO4 is needed to accurately quantify groundwater travel time. But, more data is needed to fully assess whether or not this tracer could become a valuable tool for managers.« less

  10. Low-voltage harmonic multiplying gyrotron traveling-wave amplifier in G band

    SciTech Connect (OSTI)

    Yeh, Y. S.; Guo, Y. W.; Kao, B. H.; Chen, C. H.; Wang, Z. W.; Hung, C. L.; Chang, T. H.

    2015-12-15

    Harmonic multiplying operation in a gyrotron traveling-wave amplifier (gyro-TWA) permits for magnetic field reduction and frequency multiplication. Lowering a beam voltage is an important step toward miniaturization of a harmonic multiplying gyro-TWA. However, the additional degree of freedom that is provided by the multitude cyclotron harmonics in a low-voltage harmonic multiplying gyro-TWA still easily generates various competing modes. An improved mode-selective circuit, using circular waveguides with various radii, can provide the rejection points within the frequency range to suppress competing modes. Simulated results reveal that the mode-selective circuit can provide an attenuation of more than 14 dB to suppress the competing modes. Furthermore, the performance of the gyro-TWA is analyzed for studying the sensitivity of the saturated output power and full width at half maximum bandwidth of the gyro-TWA to the beam voltage and the magnetic field. A stable low-voltage harmonic multiplying gyro-TWA with the mode-selective circuit is predicted to yield a peak output power of 24 kW at 200.4 GHz, corresponding to a saturated gain of 56 dB at an interaction efficiency of 20%. The full width at half maximum bandwidth is 3.0 GHz.

  11. Traveling-wave laser-produced-plasma energy source for photoionization laser pumping and lasers incorporating said

    DOE Patents [OSTI]

    Sher, Mark H.; Macklin, John J.; Harris, Stephen E.

    1989-09-26

    A traveling-wave, laser-produced-plasma, energy source used to obtain single-pass gain saturation of a photoionization pumped laser. A cylindrical lens is used to focus a pump laser beam to a long line on a target. Grooves are cut in the target to present a surface near normal to the incident beam and to reduce the area, and hence increase the intensity and efficiency, of plasma formation.

  12. 0.22 THz wideband sheet electron beam traveling wave tube amplifier: Cold test measurements and beam wave interaction analysis

    SciTech Connect (OSTI)

    Baig, Anisullah; Gamzina, Diana; Barchfeld, Robert; Domier, Calvin; Barnett, Larry R.; Luhmann, Neville C. Jr.

    2012-09-15

    In this paper, we describe micro-fabrication, RF measurements, and particle-in-cell (PIC) simulation modeling analysis of the 0.22 THz double-vane half period staggered traveling wave tube amplifier (TWTA) circuit. The TWTA slow wave structure comprised of two sections separated by two sever ports loaded by loss material, with integrated broadband input/output couplers. The micro-metallic structures were fabricated using nano-CNC milling and diffusion bonded in a three layer process. The 3D optical microscopy and SEM analysis showed that the fabrication error was within 2-3 {mu}m and surface roughness was measured within 30-50 nm. The RF measurements were conducted with an Agilent PNA-X network analyzer employing WR5.1 T/R modules with a frequency range of 178-228 GHz. The in-band insertion loss (S{sub 21}) for both the short section and long section (separated by a sever) was measured as {approx}-5 dB while the return loss was generally around {approx}-15 dB or better. The measurements matched well with the S-matrix simulation analysis that predicted a 3 dB bandwidth of {approx}45 GHz with an operating frequency at 220 GHz. However, the measured S{sub 21} was {approx}3 dB less than the design values, and is attributed to surface roughness and alignment issues. The confirmation measurements were conducted over the full frequency band up to 270 GHz employing a backward wave oscillator (BWO) scalar network analyzer setup employing a BWO in the frequency range 190 GHz-270 GHz. PIC simulations were conducted for the realistic TWT output power performance analysis with incorporation of corner radius of 127 {mu}m, which is inevitably induced by nano-machining. Furthermore, the S{sub 21} value in both sections of the TWT structure was reduced to correspond to the measurements by using a degraded conductivity of 10% International Annealed Copper Standard. At 220 GHz, for an elliptic sheet electron beam of 20 kV and 0.25 A, the average output power of the tube was predicted

  13. A traveling-wave forward coupler design for a new accelerating mode in a silicon woodpile accelerator

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wu, Ziran; Lee, Chunghun H.; Wootton, Kent P.; Ng, Cho -Kuen; Qi, Minghao H.; England, Robert J.

    2016-03-01

    Silicon woodpile photonic crystals provide a base structure that can be used to build a three-dimensional dielectric waveguide system for high-gradient laser driven acceleration. A new woodpile waveguide design that hosts a phase synchronous, centrally confined accelerating mode is proposed. Comparing with previously discovered silicon woodpile accelerating modes, this mode shows advantages in terms of better electron beam loading and higher achievable acceleration gradient. Several traveling-wave coupler design schemes developed for multi-cell RF cavity accelerators are adapted to the woodpile power coupler design for this new accelerating mode. Design of a forward coupled, highly efficient silicon woodpile accelerator is achieved.more » Simulation shows high efficiency of over 75% of the drive laser power coupled to this fundamental accelerating mode, with less than 15% backward wave scattering. The estimated acceleration gradient, when the coupler structure is driven at the damage threshold fluence of silicon at its operating 1.506 μm wavelength, can reach 185 MV/m. Lastly, a 17-layer woodpile waveguide structure was successfully fabricated, and the measured bandgap is in excellent agreement with simulation.« less

  14. Gain analysis of higher-order-mode amplification in a dielectric-implanted multi-beam traveling wave structure

    SciTech Connect (OSTI)

    Gee, Anthony; Shin, Young-Min

    2013-01-01

    A multi-beam traveling wave amplifier designed with an overmoded staggered double grating array was examined by small signal analysis combined with simulation. Eigenmode and S-parameter analyses show that the 2cm long slow wave structure (SWS) has 1-5dB insertion loss over the passband (TM31 mode) with ~28% cold bandwidth. Analytic gain calculation indicates that in the SWS, TM31-mode is amplified with 15–20 dB/beam at 64–84GHz with three elliptical beams of 10kV and 150mA/beam, which was compared with particle-in-cell (PIC) simulations. PIC analysis on the analysis of instability with zero-input driving excitations demonstrated that background noises and non-operating lower order modes are noticeably suppressed by implanting equidistant dielectric absorbers; the overmoded structure only allowed the desired 3rd order mode to propagate in the structure. The designed circuit structure can be widely applied to multi-beam devices for high power RF generation.

  15. Multi-time wave functions for quantum field theory

    SciTech Connect (OSTI)

    Petrat, Sren; Tumulka, Roderich

    2014-06-15

    Multi-time wave functions such as ?(t{sub 1},x{sub 1},,t{sub N},x{sub N}) have one time variable t{sub j} for each particle. This type of wave function arises as a relativistic generalization of the wave function ?(t,x{sub 1},,x{sub N}) of non-relativistic quantum mechanics. We show here how a quantum field theory can be formulated in terms of multi-time wave functions. We mainly consider a particular quantum field theory that features particle creation and annihilation. Starting from the particleposition representation of state vectors in Fock space, we introduce multi-time wave functions with a variable number of time variables, set up multi-time evolution equations, and show that they are consistent. Moreover, we discuss the relation of the multi-time wave function to two other representations, the TomonagaSchwinger representation and the Heisenberg picture in terms of operator-valued fields on spacetime. In a certain sense and under natural assumptions, we find that all three representations are equivalent; yet, we point out that the multi-time formulation has several technical and conceptual advantages. -- Highlights: Multi-time wave functions are manifestly Lorentz-covariant objects. We develop consistent multi-time equations with interaction for quantum field theory. We discuss in detail a particular model with particle creation and annihilation. We show how multi-time wave functions are related to the TomonagaSchwinger approach. We show that they have a simple representation in terms of operator valued fields.

  16. Design and performance of the traveling-wave beam chopper for the SSRL injector

    SciTech Connect (OSTI)

    Borland, M.; Weaver, J.N.; Baltay, M.; Emery, L.; Fisher, A.S.; Golceff, P.; Hettel, R.; Morales, H.; Sebek, J.; Wiedemann, H.; Youngman, B. . Stanford Synchrotron Radiation Lab.); Anderson, R. ); Miller, R.H. )

    1991-05-01

    A pulsed, split-parallel plate chopper has been designed built, and installed as part of the preinjector of the SSRL Injector. Its function is to allow the linear accelerator three consecutive S-band bunches from the long bunch train provided by a RF gun. A permanent magnet deflector (PMD) at the chopper entrance deflects the beam into an absorber when the chopper pulse is off. The beam is swept across a pair of slits at the beam output end when a 7 kV, 10-ns rise-time pulse passes in the opposite direction through the 75 {Omega} stripline formed by the deflecting plates. Bunches exiting the slits have their trajectories corrected by another PMD, and enter the linac. Beam tests demonstrate that the chopper functions as expected. 9 refs., 5 figs.

  17. TRAVELING WAVE PYROTRON

    DOE Patents [OSTI]

    Post, R.F.

    1963-06-11

    The invention relates to a pyrotron, i.e., magnetic mirror device, designed for continuous operation in producing a high-temperature fusion reaction plasma and for directly converting the plasma energy into electrical power. The device utilizes a system in which an axially symmetric magnetic field is produced and transports plasma through a first zone of progressively rising field intensity, a second reaction zone of slowly increasing intensity, and thenceforth through a third zone of progressively decreasing intensity wherein the plasma expands against the magnetic field thereby producing electrical current in magnetic field generating solenoids associated with said third zone. (AEC)

  18. Uncertainty and Sensitivity of Contaminant Travel Times from the Upgradient Nevada Test Site to the Yucca Mountain Area

    SciTech Connect (OSTI)

    J. Zhu; K. Pohlmann; J. Chapman; C. Russell; R.W.H. Carroll; D. Shafer

    2009-09-10

    Yucca Mountain (YM), Nevada, has been proposed by the U.S. Department of Energy as the nation’s first permanent geologic repository for spent nuclear fuel and highlevel radioactive waste. In this study, the potential for groundwater advective pathways from underground nuclear testing areas on the Nevada Test Site (NTS) to intercept the subsurface of the proposed land withdrawal area for the repository is investigated. The timeframe for advective travel and its uncertainty for possible radionuclide movement along these flow pathways is estimated as a result of effective-porosity value uncertainty for the hydrogeologic units (HGUs) along the flow paths. Furthermore, sensitivity analysis is conducted to determine the most influential HGUs on the advective radionuclide travel times from the NTS to the YM area. Groundwater pathways are obtained using the particle tracking package MODPATH and flow results from the Death Valley regional groundwater flow system (DVRFS) model developed by the U.S. Geological Survey (USGS). Effectiveporosity values for HGUs along these pathways are one of several parameters that determine possible radionuclide travel times between the NTS and proposed YM withdrawal areas. Values and uncertainties of HGU porosities are quantified through evaluation of existing site effective-porosity data and expert professional judgment and are incorporated in the model through Monte Carlo simulations to estimate mean travel times and uncertainties. The simulations are based on two steady-state flow scenarios, the pre-pumping (the initial stress period of the DVRFS model), and the 1998 pumping (assuming steady-state conditions resulting from pumping in the last stress period of the DVRFS model) scenarios for the purpose of long-term prediction and monitoring. The pumping scenario accounts for groundwater withdrawal activities in the Amargosa Desert and other areas downgradient of YM. Considering each detonation in a clustered region around Pahute Mesa (in

  19. Interview Travel

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

    Interview Travel Interview Travel Travel preapproval and reimbursement process information for invited Laboratory job interviewees. Contact Travel Reservations (505) 667-1692 Email Student Travel (505) 667-5859 Interview travel process Interview travel will be reimbursed only when a Laboratory organization has invited a candidate to come to the Laboratory to interview for a specific job and the following process is used. Eligible expenses are paid post-interview only. Before beginning, review

  20. Travel Reimbursement

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

    Travel Reimbursement Travel Reimbursement Travel preapproval and reimbursement process information for interviewees, students, and relocations including new regular hires, term assignment hires, post-doctoral or advance study employees, and long-term visiting staff members. Interview Travel» Graduate, Undergraduate Travel» Relocation Travel» Guest Travel» TOP STORIES - highlights of our science, people, technologies close Rio Arriba Leadership Summit addresses challenges, opportunities

  1. Cooling by Time Reversal of Atomic Matter Waves

    SciTech Connect (OSTI)

    Martin, J.; Georgeot, B.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, Universite de Toulouse III, CNRS, 31062 Toulouse (France)

    2008-02-01

    We propose an experimental scheme which allows us to realized approximate time reversal of matter waves for ultracold atoms in the regime of quantum chaos. We show that a significant fraction of the atoms return back to their original state, being at the same time cooled down by several orders of magnitude. We give a theoretical description of this effect supported by extensive numerical simulations. The proposed scheme can be implemented with existing experimental setups.

  2. Connected Traveler

    SciTech Connect (OSTI)

    Schroeder, Alex

    2015-11-01

    The Connected Traveler project is a multi-disciplinary undertaking that seeks to validate potential for transformative transportation system energy savings by incentivizing efficient traveler behavior. This poster outlines various aspects of the Connected Traveler project, including market opportunity, understanding traveler behavior and decision-making, automation and connectivity, and a projected timeline for Connected Traveler's key milestones.

  3. Relocation Travel

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

    Relocation Travel Relocation Travel Travel reimbursement process information for relocations including new regular hires, term assignment hires, post-doctoral or advance study employees, and long-term visiting staff members. Contact Gloria Salazar Relocation Office (505) 665-4484 Email Sher Robinson (505) 665-8529 Relocation travel process Reimbursement for travel includes new regular hires, term assignment hires, post-doctoral or advance study employees, and long-term visiting staff members.

  4. Guest Travel

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

    group office for reimbursement.) Guest makes reservations for airline, rental car, and hotel, in accordance with Laboratory travel regulations. After guest returns Visitor...

  5. Barrier interaction time and the Salecker-Wigner quantum clock: Wave-packet approach

    SciTech Connect (OSTI)

    Park, Chang-Soo

    2009-07-15

    The time-of-flight measurement approach of Peres based on the Salecker-Wigner quantum clock is applied to the one-dimensional scattering of a wave packet from a rectangular barrier. By directly evaluating the expectation value of the clock-time operator in the asymptotic states of wave packet long after the scattering process, we derive an average wave-packet clock time for the barrier interaction, which is expressed as an average of the stationary-state clock time over all possible initial scattering states of the wave packet. We show that the average wave-packet clock time is identical to the average dwell time of a wave packet.

  6. ZERO-TIME INDICATOR

    DOE Patents [OSTI]

    Sander, H.H.

    1960-08-30

    The travel time of a nuclear shock wave from its point of origin to a location can be determined accurately by an apparatus for noting and comparably recording both zerotime, as indicated by the electromagnetic transient associated with the nuclear detonation, and shock wave arrival time.

  7. Wave function for harmonically confined electrons in time-dependent electric and magnetostatic fields

    SciTech Connect (OSTI)

    Zhu, Hong-Ming; Chen, Jin-Wang; Pan, Xiao-Yin; Sahni, Viraht

    2014-01-14

    We derive via the interaction “representation” the many-body wave function for harmonically confined electrons in the presence of a magnetostatic field and perturbed by a spatially homogeneous time-dependent electric field—the Generalized Kohn Theorem (GKT) wave function. In the absence of the harmonic confinement – the uniform electron gas – the GKT wave function reduces to the Kohn Theorem wave function. Without the magnetostatic field, the GKT wave function is the Harmonic Potential Theorem wave function. We further prove the validity of the connection between the GKT wave function derived and the system in an accelerated frame of reference. Finally, we provide examples of the application of the GKT wave function.

  8. Travel | The Ames Laboratory

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

    Travel Travel The Office of Travel Management serves as the Department's POC for the following services: Headquarters Travel Management Center (TMC) Official Travel, Domestic and Foreign Foreign Travel Management System (FTMS) Official Travel Regulations and Guidelines U.S. Passports and Visa Services (Official and Diplomatic) Non-Refundable Airfare Guidance International Insurance for DOE Officials (MEDEX) Car Rental Hotel Reservations Travel FAQs For questions about Travel Services or the

  9. Wave

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

    1 Summer 2001 Heat Wave This summer has proved to be downright hot in the Southern Great ... Not only is a summer heat wave uncomfortable, but it can also be ARM Facilities Newsletter ...

  10. JLab Travelers and Travel Coordinators: Effective Immediately...

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

    information could result in denial of country clearance and jeopardize future travel. ... All FTMS Travel Requisitions and Electronic Country Clearance (eCC) requests must be ...

  11. Real-time fracture monitoring in Engineered Geothermal Systems with seismic waves

    SciTech Connect (OSTI)

    Jose A. Rial; Jonathan Lees

    2009-03-31

    As proposed, the main effort in this project is the development of software capable of performing real-time monitoring of micro-seismic activity recorded by an array of sensors deployed around an EGS. The main milestones are defined by the development of software to perform the following tasks: • Real-time micro-earthquake detection and location • Real-time detection of shear-wave splitting • Delayed-time inversion of shear-wave splitting These algorithms, which are discussed in detail in this report, make possible the automatic and real-time monitoring of subsurface fracture systems in geothermal fields from data collected by an array of seismic sensors. Shear wave splitting (SWS) is parameterized in terms of the polarization of the fast shear wave and the time delay between the fast and slow shear waves, which are automatically measured and stored. The measured parameters are then combined with previously measured SWS parameters at the same station and used to invert for the orientation (strike and dip) and intensity of cracks under that station. In addition, this grant allowed the collection of seismic data from several geothermal regions in the US (Coso) and Iceland (Hengill) to use in the development and testing of the software.

  12. Influence of voltage rise time on microwave generation in relativistic backward wave oscillator

    SciTech Connect (OSTI)

    Wu, Ping; Deng, Yuqun; Sun, Jun; Teng, Yan; Shi, Yanchao; Chen, Changhua

    2015-10-15

    In relativistic backward wave oscillators (RBWOs), although the slow wave structure (SWS) and electron beam determine the main characteristics of beam-wave interaction, many other factors can also significantly affect the microwave generation process. This paper investigates the influence of voltage rise time on beam-wave interaction in RBWOs. Preliminary analysis and PIC simulations demonstrate if the voltage rise time is moderately long, the microwave frequency will gradually increase during the startup process until the voltage reaches its amplitude, which can be explained by the dispersion relation. However, if the voltage rise time is long enough, the longitudinal resonance of the finitely-long SWS will force the RBWO to work with unwanted longitudinal modes for a while and then gradually hop to the wanted longitudinal mode, and this will lead to an impure microwave frequency spectrum. Besides, a longer voltage rise time will delay the startup process and thus lead to a longer microwave saturation time. And if unwanted longitudinal modes are excited due to long voltage rise time, the microwave saturation time will be further lengthened. Therefore, the voltage rise time of accelerators adopted in high power microwave technology should not be too long in case unwanted longitudinal modes are excited.

  13. Time- and power-dependent operation of a parametric spin-wave amplifier

    SciTech Connect (OSTI)

    Brächer, T.; Heussner, F.; Pirro, P.; Fischer, T.; Geilen, M.; Heinz, B.; Lägel, B.; Serga, A. A.; Hillebrands, B.

    2014-12-08

    We present the experimental observation of the localized amplification of externally excited, propagating spin waves in a transversely in-plane magnetized Ni{sub 81}Fe{sub 19} magnonic waveguide by means of parallel pumping. By employing microfocussed Brillouin light scattering spectroscopy, we analyze the dependency of the amplification on the applied pumping power and on the delay between the input spin-wave packet and the pumping pulse. We show that there are two different operation regimes: At large pumping powers, the spin-wave packet needs to enter the amplifier before the pumping is switched on in order to be amplified while at low powers the spin-wave packet can arrive at any time during the pumping pulse.

  14. Graduate, Undergraduate Student Travel

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

    Graduate, Undergraduate Travel Graduate, Undergraduate Student Travel Travel reimbursement process information for participants in the Graduate Research Assistant (GRA) and Undergraduate Student (UGS) programs Contact Travel Reservations (505) 667-1692 Email Student Travel (505) 667-5859 Email Graduate, undergraduate student travel process Travel by employees who participate in the Graduate Research Assistant (GRA) and Undergraduate Student (UGS) programs will be reimbursed only when the

  15. Time delay of wave packets during their tunnelling through a quantum diode

    SciTech Connect (OSTI)

    Ivanov, N A; Skalozub, V V

    2014-04-28

    A modified saddle-point method is used to investigate the process of propagation of a wave packet through a quantum diode. A scattering matrix is constructed for the structure in question. The case of tunnelling of a packet with a Gaussian envelope through the diode is considered in detail. The time delay and the shape of the wave packet transmitted are calculated. The dependence of the delay time on the characteristics of the input packet and the internal characteristics of the quantum diode is studied. Possible applications of the results obtained are discussed. (laser applications and other topics in quantum electronics)

  16. On-Line Travel Reservations through "Concur Travel" | The Ames...

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

    them as a travel administrator. Travel will not be booked on Concur Travel until Ames Lab Travel Worksheet has been received and reviewed by the Travel Office. Concur Travel is...

  17. Relocation Travel FAQs Travel/Moving FAQs

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

    Relocation Travel FAQs Travel/Moving FAQs When may I begin making travel and moving arrangements? No arrangements should be made prior to receiving a written offer of employment from Human Resources (HR) Division. The written offer letter is the official offer. The offer of employment must be accepted in writing (a signature on the offer letter) and returned to the Laboratory before making any travel or moving arrangements. How will I receive the relocation information? The relocation

  18. Optical imaging through turbid media with a degenerate four-wave mixing correlation time gate

    DOE Patents [OSTI]

    Sappey, Andrew D.

    1998-04-14

    Optical imaging through turbid media is demonstrated using a degenerate four-wave mixing correlation time gate. An apparatus and method for detecting ballistic and/or snake light while rejecting unwanted diffusive light for imaging structures within highly scattering media are described. Degenerate four-wave mixing (DFWM) of a doubled YAG laser in rhodamine 590 is used to provide an ultrafast correlation time gate to discriminate against light that has undergone multiple scattering and therefore has lost memory of the structures within the scattering medium. Images have been obtained of a test cross-hair pattern through highly turbid suspensions of whole milk in water that are opaque to the naked eye, which demonstrates the utility of DFWM for imaging through turbid media. Use of DFWM as an ultrafast time gate for the detection of ballistic and/or snake light in optical mammography is discussed.

  19. Statistical Evaluation of Travel Time Estimation Based on Data from Freeze-Branded Chinook Salmon on the Snake River, 1982-1990.

    SciTech Connect (OSTI)

    Smith, Steven G.; Skalski, J.R.; Giorgi, Albert E.

    1993-10-01

    The purpose of this investigation is to assess the strengths and limitations of existing freeze brand recapture data in describing the migratory dynamics of juvenile salmonids in the mainstream, impounded sections of the Snake and Columbia Rivers. With the increased concern over the threatened status of spring and summer chinook salmon in the Snake River drainage, we used representative stocks for these races as our study populations. However, statistical considerations resultant from these analyses apply to other species and drainages as well. This report describes analyses we conducted using information derived from freeze-branded groups. We examined both index production groups released from hatcheries upstream from Lower Granite Dam (1982--1990) and freeze-branded groups used as controls in smolt transportation evaluations conducted by the National Marine Fisheries Service (1986, 1989). The scope of our analysis was limited to describing travel time estimates and derived relationships, as well as reach survival estimates through the mainstem Snake River from Lower Granite to McNary Dam.

  20. Travel Requirements - ITER (June 2014

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

    Travel Requirements - ITER (June 2014) Prior to any travel under this subcontract, the ... approval, with a copy to the identified US ITER Project Office Travel Administrative ...

  1. Travel Policy | The Ames Laboratory

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

    Policy Travel Policy Travel Policy for Contractor Personnel Travel Policy Changes October 1, 2009 Per Diem Adjustments for Meals Memo or EXAMPLE...

  2. Exact Time-Dependent Nonlinear Dispersive Wave Solutions in Compressible Magnetized Plasmas Exhibiting Collapse

    SciTech Connect (OSTI)

    Chakrabarti, Nikhil; Maity, Chandan; Schamel, Hans

    2011-04-08

    Compressional waves in a magnetized plasma of arbitrary resistivity are treated with the Lagrangian fluid approach. An exact nonlinear solution with a nontrivial space and time dependence is obtained with boundary conditions as in Harris' current sheet. The solution shows competition among hydrodynamic convection, magnetic field diffusion, and dispersion. This results in a collapse of density and the magnetic field in the absence of dispersion. The dispersion effects arrest the collapse of density but not of the magnetic field. A possible application is in the early stage of magnetic star formation.

  3. Analytical estimate of phase mixing time of longitudinal Akhiezer-Polovin waves

    SciTech Connect (OSTI)

    Mukherjee, Arghya Sengupta, Sudip

    2014-11-15

    Phase mixing of a longitudinal Akhiezer-Polovin wave subjected to a small amplitude longitudinal perturbation and its eventual breaking is studied analytically. It is well known that longitudinal Akhiezer-Polovin wave subjected to arbitrarily small longitudinal perturbation breaks via the process of phase mixing at an amplitude well below its limiting amplitude [Verma et al., Phys. Rev. Lett. 108, 125005 (2012)]. We analytically show that the phase mixing time (breaking time, ω{sub p}τ{sub mix}) scales with β (phase velocity) and u{sub m}(maximum fluid velocity) as ω{sub p}τ{sub mix}∼(2πβ)/(3δ) [1/u{sub m}{sup 2}−1/4], where δ is the amplitude of velocity perturbation and ω{sub p} is the non-relativistic plasma frequency. This analytical dependence of phase mixing time on β, u{sub m}, and δ is further verified using numerical simulations based on Dawson sheet model.

  4. Travel Policy and Procedures

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2002-09-04

    To supplement the Federal Travel Regulation (41 CFR, Parts 300-304), the principal source of policy for Federal employee travel and relocation matters, and to establish DOE M 552.1-1, U.S. Department of Energy Travel Manual, dated 09-04-02, as the repository for supplementary travel requirements information for the Department of Energy (DOE). Cancels DOE 1500.2A and DOE 1500.4A. Canceled by DOE O 552.1A.

  5. Travel Policy and Procedures

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-02-17

    The Order supplements the Federal Travel Regulation as principal source of policy for Federal employee travel and relocation and establishes DOE M 552.1-1A, U.S. Department of Energy Travel Manual, dated 2-17-06, as the DOE repository for supplementary travel requirements information. Cancels DOE O 552.1-1. Canceled by DOE O 552.1A Admin Chg 1.

  6. Travel Policy and Procedures

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-02-17

    The Order supplements the Federal Travel Regulation as principal source of policy for Federal employee travel and relocation and establishes DOE M 552.1-1A, U.S. Department of Energy Travel Manual, dated 2-17-06, as the repository for supplementary travel requirements information. Supersedes DOE O 552.1. Admin Chg 1, dated 10-1-08, supersedes DOE O 552.1A.

  7. JLab Travelers and Travel Coordinators: Effective Immediately - Critical

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

    new requirements for all travel to or passing through France | Jefferson Lab Travelers and Travel Coordinators: Effective Immediately - Critical new requirements for all travel to or passing through France JLab Travelers and Travel Coordinators: Effective Immediately - Critical new requirements for all travel to or passing through France Due to increased security levels in France, it is critical for the U.S. State Department / Embassy of Paris to have the ability to quickly and directly

  8. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2002-11-08

    To establish Department of Energy (DOE) and National Nuclear Security Administration (NNSA) requirements and responsibilities governing official foreign travel by Federal and contractor employees. The Page Change 1 to the CRD issued 11-8-02, will expand the requirements for country clearance for contractors to include all official foreign travel, including travel to nonsensitive countries. Cancels DOE O 551.1. Canceled by DOE O 551.1B.

  9. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2008-06-24

    The Order sets forth requirements and responsibilities governing official foreign travel by Federal and contractor employees. Cancels DOE O 551.1B.

  10. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2012-04-12

    The order establishes requirements and responsibilities governing official foreign travel by Federal and contractor employees. Cancels DOE O 551.1C.

  11. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2012-04-02

    The order establishes DOE requirements and responsibilities governing official foreign travel by Federal and contractor employees. The Pg Chg removes the requirement to surrender official passports and replaces it with a process that requires travelers be responsible for safeguarding theirown official passports. Supersedes DOE O 551.1D, dated 4-12-12.

  12. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2012-04-02

    The order establishes DOE requirements and responsibilities governing official foreign travel by Federal and contractor employees. The proposed revisions to the Official Foreign Travel Order align it with established leave policy and update organizational responsibilities. Supersedes DOE O 551.1D Chg 1 (Pg Chg).

  13. Numerical solution of the time dependent Ginzburg-Landau equations for mixed (d + s)-wave superconductors

    SciTech Connect (OSTI)

    Gonalves, W. C.; Sardella, E.; UNESP-Universidade Estadual Paulista, IPMet-Instituto de Pesquisas Meteorolgicas, CEP 17048-699 Bauru, SP ; Becerra, V. F.; Miloevi?, M. V.; Peeters, F. M.; Departamento de Fsica, Universidade Federal do Cear, 60455-900 Fortaleza, Cear

    2014-04-15

    The time-dependent Ginzburg-Landau formalism for (d + s)-wave superconductors and their representation using auxiliary fields is investigated. By using the link variable method, we then develop suitable discretization of these equations. Numerical simulations are carried out for a mesoscopic superconductor in a homogeneous perpendicular magnetic field which revealed peculiar vortex states.

  14. Accounting Techinican (Travel Duties)

    Broader source: Energy.gov [DOE]

    This position may be filled either at Morgantown, WV or Pittsburgh, PA. A successful candidate in this position will provide technical accounting support to the travel program at the National...

  15. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-08-25

    To establish Department of Energy (DOE) and National Nuclear Security Administration (NNSA) requirements and responsibilities governing official foreign travel by Federal and contractor employees. Cancels DOE O 551.1. Canceled by DOE O 551.1B.

  16. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2003-08-19

    To establish Department of Energy (DOE) and National Nuclear Security Administration (NNSA) requirements and responsibilities governing official foreign travel by Federal and contractor employees. Cancels DOE O 551.1A. Canceled by DOE O 551.1C.

  17. Official Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-01-31

    Establishes Department of Energy (DOE) requirements and responsibilities governing official foreign travel by Federal and contract employees. Cancels DOE O 1500.3. Canceled by DOE O 551.1A.

  18. Accounting Technician (Travel Duties)

    Broader source: Energy.gov [DOE]

    This position may be filled either at Morgantown, WV or Pittsburgh, PA. A successful candidate in this position will provide technical accounting support to the travel program at the National...

  19. A study of cooling time reduction of interferometric cryogenic gravitational wave detectors using a high-emissivity coating

    SciTech Connect (OSTI)

    Sakakibara, Y.; Yamamoto, K.; Chen, D.; Tokoku, C.; Uchiyama, T.; Ohashi, M.; Kuroda, K.; Kimura, N.; Suzuki, T.; Koike, S.

    2014-01-29

    In interferometric cryogenic gravitational wave detectors, there are plans to cool mirrors and their suspension systems (payloads) in order to reduce thermal noise, that is, one of the fundamental noise sources. Because of the large payload masses (several hundred kg in total) and their thermal isolation, a cooling time of several months is required. Our calculation shows that a high-emissivity coating (e.g. a diamond-like carbon (DLC) coating) can reduce the cooling time effectively by enhancing radiation heat transfer. Here, we have experimentally verified the effect of the DLC coating on the reduction of the cooling time.

  20. Optical pin apparatus for measuring the arrival time and velocity of shock waves and particles

    DOE Patents [OSTI]

    Benjamin, R.F.

    1983-10-18

    An apparatus for the detection of the arrival and for the determination of the velocity of disturbances such as shock-wave fronts and/or projectiles. Optical pins using fluid-filled microballoons as the light source and an optical fiber as a link to a photodetector have been used to investigate shock-waves and projectiles. A microballoon filled with a noble gas is affixed to one end of a fiber-optic cable, and the other end of the cable is attached to a high-speed streak camera. As the shock-front or projectile compresses the microballoon, the gas inside is heated and compressed producing a bright flash of light. The flash of light is transmitted via the optic cable to the streak camera where it is recorded. One image-converter streak camera is capable of recording information from more than 100 microballoon-cable combinations simultaneously.

  1. Optical pin apparatus for measuring the arrival time and velocity of shock waves and particles

    DOE Patents [OSTI]

    Benjamin, R.F.

    1987-03-10

    An apparatus is disclosed for the detection of the arrival and for the determination of the velocity of disturbances such as shock-wave fronts and/or projectiles. Optical pins using fluid-filled microballoons as the light source and an optical fiber as a link to a photodetector have been used to investigate shock-waves and projectiles. A microballoon filled with a noble gas is affixed to one end of a fiber-optic cable, and the other end of the cable is attached to a high-speed streak camera. As the shock-front or projectile compresses the microballoon, the gas inside is heated and compressed producing a bright flash of light. The flash of light is transmitted via the optic cable to the streak camera where it is recorded. One image-converter streak camera is capable of recording information from more than 100 microballoon-cable combinations simultaneously. 3 figs.

  2. Optical pin apparatus for measuring the arrival time and velocity of shock waves and particles

    DOE Patents [OSTI]

    Benjamin, Robert F.

    1987-01-01

    An apparatus for the detection of the arrival and for the determination of the velocity of disturbances such as shock-wave fronts and/or projectiles. Optical pins using fluid-filled microballoons as the light source and an optical fiber as a link to a photodetector have been used to investigate shock-waves and projectiles. A microballoon filled with a noble gas is affixed to one end of a fiber-optic cable, and the other end of the cable is attached to a high-speed streak camera. As the shock-front or projectile compresses the microballoon, the gas inside is heated and compressed producing a bright flash of light. The flash of light is transmitted via the optic cable to the streak camera where it is recorded. One image-converter streak camera is capable of recording information from more than 100 microballoon-cable combinations simultaneously.

  3. Constraining dark matter late-time energy injection: decays and p-wave annihilations

    SciTech Connect (OSTI)

    Diamanti, Roberta; Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C.; Lopez-Honorez, Laura E-mail: llopezho@vub.ac.be E-mail: sergio.palomares.ruiz@ific.uv.es

    2014-02-01

    We use the latest cosmic microwave background (CMB) observations to provide updated constraints on the dark matter lifetime as well as on p-wave suppressed annihilation cross sections in the 1 MeV to 1 TeV mass range. In contrast to scenarios with an s-wave dominated annihilation cross section, which mainly affect the CMB close to the last scattering surface, signatures associated with these scenarios essentially appear at low redshifts (z∼<50) when structure began to form, and thus manifest at lower multipoles in the CMB power spectrum. We use data from Planck, WMAP9, SPT and ACT, as well as Lyman–α measurements of the matter temperature at z ∼ 4 to set a 95% confidence level lower bound on the dark matter lifetime of ∼ 4 × 10{sup 25} s for m{sub χ} = 100 MeV. This bound becomes lower by an order of magnitude at m{sub χ} = 1 TeV due to inefficient energy deposition into the intergalactic medium. We also show that structure formation can enhance the effect of p-wave suppressed annihilation cross sections by many orders of magnitude with respect to the background cosmological rate, although even with this enhancement, CMB constraints are not yet strong enough to reach the thermal relic value of the cross section.

  4. Reporting Unofficial Foreign Travel

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2000-12-15

    Establishes requirements for the reporting of unofficial travel to foreign countries by DOE and DOE contractor employees that hold an access authorization (personnel security clearances). DOE N 251.40, dated 5/3/01, extended this directive until 12/31/01.

  5. Local timespace mesh refinement for simulation of elastic wave propagation in multi-scale media

    SciTech Connect (OSTI)

    Kostin, Victor; Lisitsa, Vadim; Reshetova, Galina; Tcheverda, Vladimir

    2015-01-15

    This paper presents an original approach to local timespace grid refinement for the numerical simulation of wave propagation in models with localized clusters of micro-heterogeneities. The main features of the algorithm are the application of temporal and spatial refinement on two different surfaces; the use of the embedded-stencil technique for the refinement of grid step with respect to time; the use of the Fast Fourier Transform (FFT)-based interpolation to couple variables for spatial mesh refinement. The latter makes it possible to perform filtration of high spatial frequencies, which provides stability in the proposed finite-difference schemes. In the present work, the technique is implemented for the finite-difference simulation of seismic wave propagation and the interaction of such waves with fluid-filled fractures and cavities of carbonate reservoirs. However, this approach is easy to adapt and/or combine with other numerical techniques, such as finite elements, discontinuous Galerkin method, or finite volumes used for approximation of various types of linear and nonlinear hyperbolic equations.

  6. A coherent method for the detection and parameter estimation of continuous gravitational wave signals using a pulsar timing array

    SciTech Connect (OSTI)

    Wang, Yan; Mohanty, Soumya D.; Jenet, Fredrick A. [Department of Physics and Astronomy, University of Texas at Brownsville, 1 West University Boulevard, Brownsville, TX 78520 (United States)

    2014-11-01

    The use of a high precision pulsar timing array is a promising approach to detecting gravitational waves in the very low frequency regime (10{sup 6}-10{sup 9} Hz) that is complementary to ground-based efforts (e.g., LIGO, Virgo) at high frequencies (?10-10{sup 3} Hz) and space-based ones (e.g., LISA) at low frequencies (10{sup 4}-10{sup 1} Hz). One of the target sources for pulsar timing arrays is individual supermassive black hole binaries which are expected to form in galactic mergers. In this paper, a likelihood-based method for detection and parameter estimation is presented for a monochromatic continuous gravitational wave signal emitted by such a source. The so-called pulsar terms in the signal that arise due to the breakdown of the long-wavelength approximation are explicitly taken into account in this method. In addition, the method accounts for equality and inequality constraints involved in the semi-analytical maximization of the likelihood over a subset of the parameters. The remaining parameters are maximized over numerically using Particle Swarm Optimization. Thus, the method presented here solves the monochromatic continuous wave detection and parameter estimation problem without invoking some of the approximations that have been used in earlier studies.

  7. P- and S-body wave tomography of the state of Nevada.

    SciTech Connect (OSTI)

    Preston, Leiph

    2010-04-01

    P- and S-body wave travel times collected from stations in and near the state of Nevada were inverted for P-wave velocity and the Vp/Vs ratio. These waves consist of Pn, Pg, Sn and Sg, but only the first arriving P and S waves were used in the inversion. Travel times were picked by University of Nevada Reno colleagues and were culled for inclusion in the tomographic inversion. The resulting tomographic model covers the entire state of Nevada to a depth of {approx}90 km; however, only the upper 40 km indicate relatively good resolution. Several features of interest are imaged including the Sierra Nevada, basin structures, and low velocities at depth below Yucca Mountain. These velocity structure images provide valuable information to aide in the interpretation of geothermal resource areas throughout the state on Nevada.

  8. Travel Resources | The Ames Laboratory

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

    Resources Airline Baggage Policies Amtrak Argonne Guest House Association of Corporate Travel Executives Database of hotels that meet fire safety code GSA Per Diem Rates Iowa Road Work ISU - Office Procedure Guide - Travel Policies Map Quest Atlas National Business Travel Association Weather Channel Web Flyer

  9. travel-demand-modeling

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

    Travel Demand Modeling for a Small sized MPO Using TRANSIMS Mohammad Sharif Ullah Champaign County Regional Planning Commission 1776 E Washington Street, Urbana, IL 61802 Phone: 217 328 3313 Ext 124 Email: This email address is being protected from spambots. You need JavaScript enabled to view it. List of Authors ================ Mohammad Sharif Ullah, Senior Transportation Engineer, CCRPC, Urbana, IL Asadur Rahman, PhD student, IIT, Chicago, IL Rita Morocoima-Black, Planning & Comm.

  10. The application of domain decomposition to time-domain computations of nonlinear water waves with a panel method

    SciTech Connect (OSTI)

    De Haas, P.C.A.; Zandbergen, P.J.

    1996-12-01

    In this paper an iterative domain decomposition method for the solution of Laplace`s equation is described and its effectiveness in time-domain computations of nonlinear water waves with a panel method is investigated. An important aspect of these computations is the varying shape of the free surface. The convergence of the iterative method is fast and leads to a speedup of the computations in the aforementioned application. The domain decomposition method gives a considerable reduction of memory requirements. Furthermore, it lends itself naturally for parallel computing. 18 refs., 9 figs., 2 tabs.

  11. A real-time heart rate analysis for a remote millimeter wave I-Q sensor.

    SciTech Connect (OSTI)

    Bakhtiari, S.; Liao, S.; Elmer, T.; Gopalsami, N.; Raptis, A. C.

    2011-06-01

    This paper analyzes heart rate (HR) information from physiological tracings collected with a remote millimeter wave (mmW) I-Q sensor for biometric monitoring applications. A parameter optimization method based on the nonlinear Levenberg-Marquardt algorithm is used. The mmW sensor works at 94 GHz and can detect the vital signs of a human subject from a few to tens of meters away. The reflected mmW signal is typically affected by respiration, body movement, background noise, and electronic system noise. Processing of the mmW radar signal is, thus, necessary to obtain the true HR. The down-converted received signal in this case consists of both the real part (I-branch) and the imaginary part (Q-branch), which can be considered as the cosine and sine of the received phase of the HR signal. Instead of fitting the converted phase angle signal, the method directly fits the real and imaginary parts of the HR signal, which circumvents the need for phase unwrapping. This is particularly useful when the SNR is low. Also, the method identifies both beat-to-beat HR and individual heartbeat magnitude, which is valuable for some medical diagnosis applications. The mean HR here is compared to that obtained using the discrete Fourier transform.

  12. Interviewee Travel Regulations Scope

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

    rucks that travel in the western United States will soon be able to operate clean-burning alternative fuel vehicles (AFVs) along the Interstate Clean Transpor- tation Corridor (ICTC). The ICTC project is the first effort to develop clean transportation corridors to connect Los Angeles, San Bernar- dino, the San Joaquin Valley, Sacra- mento/San Francisco, Salt Lake City, Reno, and Las Vegas along routes 1-15, 1-80, and 1-5/CA-99. The ICTC team, headed by California- based Gladstein and

  13. Time-fractional Gardner equation for ion-acoustic waves in negative-ion-beam plasma with negative ions and nonthermal nonextensive electrons

    SciTech Connect (OSTI)

    Guo, Shimin Mei, Liquan; Zhang, Zhengqiang

    2015-05-15

    Nonlinear propagation of ion-acoustic waves is investigated in a one-dimensional, unmagnetized plasma consisting of positive ions, negative ions, and nonthermal electrons featuring Tsallis distribution that is penetrated by a negative-ion-beam. The classical Gardner equation is derived to describe nonlinear behavior of ion-acoustic waves in the considered plasma system via reductive perturbation technique. We convert the classical Gardner equation into the time-fractional Gardner equation by Agrawal's method, where the time-fractional term is under the sense of Riesz fractional derivative. Employing variational iteration method, we construct solitary wave solutions of the time-fractional Gardner equation with initial condition which depends on the nonlinear and dispersion coefficients. The effect of the plasma parameters on the compressive and rarefactive ion-acoustic solitary waves is also discussed in detail.

  14. Omega World Travel Awarded JLab Contract for Travel Services | Jefferson

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

    Lab Who is Omega World Travel? Omega World Travel has over 43 years of experience in the travel industry with a diversified customer base across multiple industries as well as DOE Laboratories. When is the Omega "Go-Live" date? The "Go-Live" date is Monday, August 1, 2016. Why did we select Omega World Travel? Omega's capabilities and experience, coupled with advantageous pricing and customer satisfaction, resulted in their selection. What does this mean to me? The Concur

  15. Foreign Travel | The Ames Laboratory

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

    Guidance Foreign Trip Report Template Trip Report Example 1 Trip Report Example 2 Insurance: Travelers are eligible for the Cultural Insurance Services International (CISI)...

  16. Optical Square-Wave Clock Generation Based on an All-Optical Flip-Flop

    SciTech Connect (OSTI)

    Kaplan, A.M.; Agrawal, G.P.; Maywar, D.N.

    2010-03-10

    We demonstrate optical square-wave clock generation based on an all-optical flip-flop. The bistable output power from a resonant-type semiconductor optical amplifier (SOA) is switched ON and OFF by modulating its input with its output via cross-gain modulation in a traveling-wave SOA. All active components are driven by dc currents, and the wavelength and clock frequency are selectable. A clock frequency of 3.5 MHz is demonstrated, limited by the time of flight between bulk optical components. Optical square-wave clock signals are promising for applications in photonic integrated circuits and all-optical signal processing.

  17. Influence of autoignition delay time characteristics of different fuels on pressure waves and knock in reciprocating engines

    SciTech Connect (OSTI)

    Bradley, D.; Kalghatgi, G.T.

    2009-12-15

    The functional relationship of autoignition delay time with temperature and pressure is employed to derive the propagation velocities of autoignitive reaction fronts for particular reactivity gradients, once autoignition has been initiated. In the present study of a variety of premixtures, with different functional relationships, such gradients comprise fixed initial temperature gradients. The smaller is the ratio of the acoustic speed through the mixture to the localised velocity of the autoignitive front, the greater are the amplitude and frequency of the induced pressure wave. This might lead to damaging engine knock. At higher values of the ratio, the autoignition can be benign with only small over-pressures. This approach to the effects of autoignition is confirmed by its application to a variety of experimental studies involving: (i)Imposed temperature gradients in a rapid compression and expansion machine. (ii)Onset of knock in an engine with advancing spark timing. (iii)Development of autoignition at a single hot spot in an engine. (iv)Autoignition fronts initiated by several hot spots. There is much diversity in the effects that can be produced by different fuels in different ranges of temperature and pressure. Higher values of autoignitive propagation speeds lead to increasingly severe engine knock. Such effects cannot always be predicted from the Research and Motor octane numbers. (author)

  18. Omega World Travel Awarded JLab Contract for Travel Services | Jefferson

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

    Lab Effective today, ALL travel to go through Omega World Travel. The Concur On-line Travel System is up and running. You can access it now. Questions / Concerns Omega representatives will be holding informational / training sessions August 1st 3:00pm - 4:00pm and August 2nd 2:00pm - 3:00pm in the Cebaf Center Auditorium. All staff are encouraged to attend. Topics will cover: Introduction of Omega's Account Manager, Reservation Agent, and Transition Team, Elimination of on-site agent, Who to

  19. ORISE: Travelers' Health Campaign | How ORISE is Making a Difference

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

    Travelers' Health Campaign Travelers' Health Campaign takes critical messages worldwide Travelers' Health Campaign poster Click image to enlarge Traveling can be a dangerous...

  20. NEUP Student Travel Request Form | Department of Energy

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

    Student Travel Request Form NEUP Student Travel Request Form NEUP Fellowship Travel Request Form PDF icon Student Travel Request Form.pdf More Documents & Publications Investing in ...

  1. Chapter 3. Vehicle-Miles Traveled

    U.S. Energy Information Administration (EIA) Indexed Site

    3. Vehicle-Miles Traveled Chapter 3. Vehicle-Miles Traveled Vehicle-miles traveled--the number of miles that residential vehicles are driven--is probably the most important...

  2. QUASI-PERIODIC FAST-MODE WAVE TRAINS WITHIN A GLOBAL EUV WAVE AND SEQUENTIAL TRANSVERSE OSCILLATIONS DETECTED BY SDO/AIA

    SciTech Connect (OSTI)

    Liu Wei; Nitta, Nariaki V.; Aschwanden, Markus J.; Schrijver, Carolus J.; Title, Alan M.; Tarbell, Theodore D.; Ofman, Leon

    2012-07-01

    We present the first unambiguous detection of quasi-periodic wave trains within the broad pulse of a global EUV wave (so-called EIT wave) occurring on the limb. These wave trains, running ahead of the lateral coronal mass ejection (CME) front of 2-4 times slower, coherently travel to distances {approx}> R{sub Sun }/2 along the solar surface, with initial velocities up to 1400 km s{sup -1} decelerating to {approx}650 km s{sup -1}. The rapid expansion of the CME initiated at an elevated height of 110 Mm produces a strong downward and lateral compression, which may play an important role in driving the primary EUV wave and shaping its front forwardly inclined toward the solar surface. The wave trains have a dominant 2 minute periodicity that matches the X-ray flare pulsations, suggesting a causal connection. The arrival of the leading EUV wave front at increasing distances produces an uninterrupted chain sequence of deflections and/or transverse (likely fast kink mode) oscillations of local structures, including a flux-rope coronal cavity and its embedded filament with delayed onsets consistent with the wave travel time at an elevated (by {approx}50%) velocity within it. This suggests that the EUV wave penetrates through a topological separatrix surface into the cavity, unexpected from CME-caused magnetic reconfiguration. These observations, when taken together, provide compelling evidence of the fast-mode MHD wave nature of the primary (outer) fast component of a global EUV wave, running ahead of the secondary (inner) slow component of CME-caused restructuring.

  3. ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION...

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

    9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) This schedule covers records documenting the ...

  4. Microsoft Word - Travel Checklist.doc

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

    kinds of tickets are and are not reimbursable are, in conjunction with the ongoing globalization of airline and other travel consortiums, complex enough that whether a travel...

  5. Effect of trapped electron on the dust ion acoustic waves in dusty plasma using time fractional modified Korteweg-de Vries equation

    SciTech Connect (OSTI)

    Nazari-Golshan, A.; Nourazar, S. S.; Department of Mechanical Engineering, Amirkabir University of Technology, Tehran

    2013-10-15

    The time fractional modified Korteweg-de Vries (TFMKdV) equation is solved to study the nonlinear propagation of small but finite amplitude dust ion-acoustic (DIA) solitary waves in un-magnetized dusty plasma with trapped electrons. The plasma is composed of a cold ion fluid, stationary dust grains, and hot electrons obeying a trapped electron distribution. The TFMKdV equation is derived by using the semi-inverse and Agrawal's methods and then solved by the Laplace Adomian decomposition method. Our results show that the amplitude of the DIA solitary waves increases with the increase of time fractional order β, the wave velocity v{sub 0}, and the population of the background free electrons λ. However, it is vice-versa for the deviation from isothermality parameter b, which is in agreement with the result obtained previously.

  6. A staggered-grid finite-difference scheme optimized in the timespace domain for modeling scalar-wave propagation in geophysical problems

    SciTech Connect (OSTI)

    Tan, Sirui; Huang, Lianjie

    2014-11-01

    For modeling scalar-wave propagation in geophysical problems using finite-difference schemes, optimizing the coefficients of the finite-difference operators can reduce numerical dispersion. Most optimized finite-difference schemes for modeling seismic-wave propagation suppress only spatial but not temporal dispersion errors. We develop a novel optimized finite-difference scheme for numerical scalar-wave modeling to control dispersion errors not only in space but also in time. Our optimized scheme is based on a new stencil that contains a few more grid points than the standard stencil. We design an objective function for minimizing relative errors of phase velocities of waves propagating in all directions within a given range of wavenumbers. Dispersion analysis and numerical examples demonstrate that our optimized finite-difference scheme is computationally up to 2.5 times faster than the optimized schemes using the standard stencil to achieve the similar modeling accuracy for a given 2D or 3D problem. Compared with the high-order finite-difference scheme using the same new stencil, our optimized scheme reduces 50 percent of the computational cost to achieve the similar modeling accuracy. This new optimized finite-difference scheme is particularly useful for large-scale 3D scalar-wave modeling and inversion.

  7. Time evolution of nonplanar dust ion-acoustic solitary waves in a charge varying dusty plasma with superthermal electrons

    SciTech Connect (OSTI)

    Mayout, Saliha; Tribeche, Mouloud; Sahu, Biswajit

    2015-12-15

    A theoretical study on the nonlinear propagation of nonplanar (cylindrical and spherical) dust ion-acoustic solitary waves (DIASW) is carried out in a dusty plasma, whose constituents are inertial ions, superthermal electrons, and charge fluctuating stationary dust particles. Using the reductive perturbation theory, a modified Korteweg-de Vries equation is derived. It is shown that the propagation characteristics of the cylindrical and spherical DIA solitary waves significantly differ from those of their one-dimensional counterpart.

  8. Molten metal feed system controlled with a traveling magnetic field

    DOE Patents [OSTI]

    Praeg, Walter F.

    1991-01-01

    A continuous metal casting system in which the feed of molten metal is controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir so that p.sub.c =p.sub.g -p.sub.m where p.sub.c is the desired pressure in the caster, p.sub.g is the gravitational pressure in the duct exerted by the force of the head of molten metal in the reservoir, and p.sub.m is the electromagnetic pressure exerted by the force of the magnetic field traveling wave produced by the linear induction motor. The invention also includes feedback loops to the linear induction motor to control the casting pressure in response to measured characteristics of the metal being cast.

  9. Shock wave compression of hexagonal-close-packed metal single crystals: Time-dependent, anisotropic elastic-plastic response of beryllium

    SciTech Connect (OSTI)

    Winey, J. M.; Gupta, Y. M.

    2014-07-21

    Understanding and modeling the response of hcp metals to high stress impulsive loading is challenging because the lower crystal symmetry, compared to cubic metals, results in a significantly more complex material response. To gain insight into the inelastic deformation of hcp metals subjected to high dynamic stresses, shock wave compression of single crystals provides a useful approach because different inelastic deformation mechanisms can be examined selectively by shock compression along different crystal orientations. As a representative example, we report, here, on wave propagation simulations for beryllium (Be) single crystals shocked along the c-axis, a-axis, and several low-symmetry directions to peak stresses reaching 7?GPa. The simulations utilized a time-dependent, anisotropic material model that incorporated dislocation dynamics, deformation twinning, and shear cracking based descriptions of inelastic deformation. The simulation results showed good overall agreement with measured wave profiles for all the different crystal orientations examined [Pope and Johnson, J. Appl. Phys. 46, 720 (1975)], including features arising from wave mode coupling due to the highly anisotropic inelastic response of Be. This good agreement demonstrates that the measured profiles can be understood in terms of dislocation slip along basal, prismatic, and pyramidal planes, together with deformation twinning along (101{sup }2) planes. Our results show that the response of shocked Be single crystals involves the simultaneous operation of multiple, distinct inelastic deformation mechanisms for all orientations except the c-axis. For shocked c-axis Be, the measured wave profiles do not provide good discrimination between pyramidal slip and other inelastic deformation mechanisms, such as shear cracking. The findings presented here provide insight into the complex inelastic deformation response of shocked Be single crystals and are expected to be useful for other hcp crystals. More

  10. Measuring tides and binary parameters from gravitational wave data and eclipsing timings of detached white dwarf binaries

    SciTech Connect (OSTI)

    Shah, Sweta; Nelemans, Gijs

    2014-08-20

    The discovery of the most compact detached white dwarf (WD) binary SDSS J065133.33+284423.3 has been discussed in terms of probing the tidal effects in WDs. This system is also a verification source for the space-based gravitational wave (GW) detector, eLISA, or the evolved Laser Interferometer Space Antenna, which will observe short-period compact Galactic binaries with P {sub orb} ≲ 5 hr. We address the prospects of performing tidal studies using eLISA binaries by showing the fractional uncertainties in the orbital decay rate, f-dot , and the rate of that decay, f{sup ¨} expected from both the GW and electromagnetic (EM) data for some of the high-f binaries. We find that f-dot and f{sup ¨} can be measured using GW data only for the most massive WD binaries observed at high frequencies. From timing the eclipses for ∼10 yr, we find that f-dot can be known to ∼0.1% for J0651. We find that from GW data alone, measuring the effects of tides in binaries is (almost) impossible. We also investigate the improvement in the knowledge of the binary parameters by combining the GW amplitude and inclination with EM data with and without f-dot . In our previous work, we found that EM data on distance constrained the 2σ uncertainty in chirp mass to 15%-25% whereas adding f-dot reduces it to 0.11%. EM data on f-dot also constrain the 2σ uncertainty in distance to 35%-19%. EM data on primary mass constrain the secondary mass m {sub 2} to factors of two to ∼40% whereas adding f-dot reduces this to 25%. Finally, using single-line spectroscopic data constrains 2σ uncertainties in both the m {sub 2}, d to factors of two to ∼40%. Adding EM data on f-dot reduces these 2σ uncertainties to ≤25% and 6%-19%, respectively. Thus we find that EM measurements of f-dot and radial velocity are valuable in constraining eLISA binary parameters.

  11. 2001 New York State NHTS: Travel Patterns of Special Populations

    SciTech Connect (OSTI)

    Hu, Patricia S; Reuscher, Tim

    2010-03-01

    pertinent to geographic areas that are significantly smaller than what the national NHTS data allowed. The final sample size for New York State was 13,423 usable households. In this report, Oak Ridge National Laboratory (ORNL) identifies and analyzes differences, if any, in travel patterns that are attributable to demographic characteristics (e.g., gender, age, race and ethnicity), household characteristics (e.g., low income households, zero and one car households), modal characteristics and geographic location. Travel patterns of those who work at home are examined and compared to those of conventional workers, as well as those who do not work. Focus is given to trip frequency, travel by time of day, trip purpose, and mode choice. For example, included in this analysis is the mobility of the elderly population in New York State. The American society is undergoing a major demographic transformation that is resulting in a greater percentage of older individuals in the population. In addition to demographic changes, recent travel surveys show that an increasing number of older individuals are licensed to drive and that they drive more than their same age cohort did a decade ago. Cohort differences in driving are particularly apparent - not only are more of today's elderly population licensed to drive than their age cohort two decades ago, they also drive more. Equally important are the increase in immigration and in racial and cultural diversity. This report also discusses vehicle availability, socioeconomic characteristics, travel trends (e.g., miles travelled, distance driven, commute patterns), and the transportation accessibility of these populations. Specifically, this report addresses in detail the travel behavior of the following special populations: (1) the elderly, defined as those who were 65 years old or older, (2) low-income households, (3) ethnic groups and immigrants, and (4) those who worked at home.

  12. Quantifying the {sup 12}C+{sup 12}C sub-Coulomb fusion with the time-dependent wave-packet method

    SciTech Connect (OSTI)

    Diaz-Torres, Alexis; Wiescher, Michael

    2012-10-20

    This contribution provides a preliminary study of the {sup 12}C+{sup 12}C sub-Coulomb fusion reaction using the time-dependent wave-packet method within a nuclear molecular picture. The theoretical sub-Coulomb fusion resonances seem to correspond well with observations. The present method might be a more suitable tool for expanding the cross-section predictions towards lower energies than the commonly used potential-model approximation.

  13. Travel Office creates on-line guide to help travelers | The Ames Laboratory

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

    Travel Office creates on-line guide to help travelers The Ames Lab Travel Office has created a couple of informational tools found on their web page to help assist travelers while making travel arrangements. "How to Fill Out a Travel Worksheet" can be found under the "Instructions" tab. The guide walks you step-by-step in filling out a travel worksheet. Also, the "Travel Arrangement Guide" can help with general questions and this is found under the "Making

  14. Developing regionalized models of lithospheric thickness and velocity structure across Eurasia and the Middle East from jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities

    SciTech Connect (OSTI)

    Julia, J; Nyblade, A; Hansen, S; Rodgers, A; Matzel, E

    2009-07-06

    In this project, we are developing models of lithospheric structure for a wide variety of tectonic regions throughout Eurasia and the Middle East by regionalizing 1D velocity models obtained by jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities. We expect the regionalized velocity models will improve our ability to predict travel-times for local and regional phases, such as Pg, Pn, Sn and Lg, as well as travel-times for body-waves at upper mantle triplication distances in both seismic and aseismic regions of Eurasia and the Middle East. We anticipate the models will help inform and strengthen ongoing and future efforts within the NNSA labs to develop 3D velocity models for Eurasia and the Middle East, and will assist in obtaining model-based predictions where no empirical data are available and for improving locations from sparse networks using kriging. The codes needed to conduct the joint inversion of P-wave receiver functions (PRFs), S-wave receiver functions (SRFs), and dispersion velocities have already been assembled as part of ongoing research on lithospheric structure in Africa. The methodology has been tested with synthetic 'data' and case studies have been investigated with data collected at an open broadband stations in South Africa. PRFs constrain the size and S-P travel-time of seismic discontinuities in the crust and uppermost mantle, SRFs constrain the size and P-S travel-time of the lithosphere-asthenosphere boundary, and dispersion velocities constrain average S-wave velocity within frequency-dependent depth-ranges. Preliminary results show that the combination yields integrated 1D velocity models local to the recording station, where the discontinuities constrained by the receiver functions are superimposed to a background velocity model constrained by the dispersion velocities. In our first year of this project we will (i) generate 1D velocity models for open broadband seismic stations in the

  15. Traveling-Wave Thermoacoustic Engines With Internal Combustion

    DOE Patents [OSTI]

    Weiland, Nathan Thomas; Zinn, Ben T.; Swift, Gregory William

    2004-05-11

    Thermoacoustic devices are disclosed wherein, for some embodiments, a combustion zone provides heat to a regenerator using a mean flow of compressible fluid. In other embodiments, burning of a combustible mixture within the combustion zone is pulsed in phase with the acoustic pressure oscillations to increase acoustic power output. In an example embodiment, the combustion zone and the regenerator are thermally insulated from other components within the thermoacoustic device.

  16. Precise Calculation of Traveling-Wave Periodic Structure

    SciTech Connect (OSTI)

    Wang, L.; Li, Z.; Seryi, A.; /SLAC

    2007-07-06

    The effects of the round edge beam hole on the frequency and wake field are studied using variational method, which allows for rounded iris disk hole without any approximation in shape treatment. The frequency and wake field of accelerating mode and dipole mode are studied for different edge radius cases, including the flat edge shape that is often used to approximately represent the actual structure geometry. The edge hole shape has weak effect on the frequency, but much effect on the wake field. Our study shows that the amounts of wake fields are not precise enough with the assumption of the flat edge beam hole instead of round edge.

  17. New York Household Travel Patterns: A Comparison Analysis

    SciTech Connect (OSTI)

    Hu, Patricia S; Reuscher, Tim

    2007-05-01

    In 1969, the U. S. Department of Transportation began collecting detailed data on personal travel to address various transportation planning issues. These issues range from assessing transportation investment programs to developing new technologies to alleviate congestion. This 1969 survey was the birth of the Nationwide Personal Transportation Survey (NPTS). The survey was conducted again in 1977, 1983, 1990 and 1995. Longer-distance travel was collected in 1977 and 1995. In 2001, the survey was renamed to the National Household Travel Survey (NHTS) and collected both daily and longer-distance trips in one survey. In addition to the number of sample households that the national NPTS/NHTS survey allotted to New York State (NYS), the state procured an additional sample of households in both the 1995 and 2001 surveys. In the 1995 survey, NYS procured an addition sample of more than 9,000 households, increasing the final NY NPTS sample size to a total of 11,004 households. Again in 2001, NYS procured 12,000 additional sample households, increasing the final New York NHTS sample size to a total of 13,423 households with usable data. These additional sample households allowed NYS to address transportation planning issues pertinent to geographic areas significantly smaller than for what the national NPTS and NHTS data are intended. Specifically, these larger sample sizes enable detailed analysis of twelve individual Metropolitan Planning Organizations (MPOs). Furthermore, they allowed NYS to address trends in travel behavior over time. In this report, travel data for the entire NYS were compared to those of the rest of the country with respect to personal travel behavior and key travel determinants. The influence of New York City (NYC) data on the comparisons of the state of New York to the rest of the country was also examined. Moreover, the analysis examined the relationship between population density and travel patterns, and the similarities and differences among New

  18. Time-periodic solutions of the Benjamin-Ono equation

    SciTech Connect (OSTI)

    Ambrose , D.M.; Wilkening, Jon

    2008-04-01

    We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations.

  19. MHK Technologies/Seatricity wave energy converter | Open Energy...

    Open Energy Info (EERE)

    In the simplest terms, a float travels up and down with the waves and operates a pump to pressurise sea water which is piped ashore. Many individual pumps are connected...

  20. Photochemistry of the water dimer: Time-dependent quantum wave-packet description of the dynamics at the S{sub 1}-S{sub 0} conical intersection

    SciTech Connect (OSTI)

    Chmura, Bartosz; Rode, Michal F.; Sobolewski, Andrzej L.; Lan Zhenggang

    2009-10-07

    The photoinduced electron-driven proton-transfer dynamics of the water-dimer system has been investigated by time-dependent quantum wave-packet calculations. The main nuclear degrees of freedom driving the system from the Frank-Condon region to the S{sub 0}-S{sub 1} conical intersection are the distance between the oxygen atoms and the displacement of the hydrogen atom from the oxygen-oxygen bond center. Two important coupling modes have been investigated: Rotation of the H-donating water dangling proton and asymmetric stretching of the H-accepting water dangling protons'O{sub a}H bonds. Potential energy surfaces of the ground and lowest excited electronic states have been constructed on the basis of ab initio calculations. The time-dependent quantum wave-packet propagation has been employed within the (2 + 1)-dimensional systems for the description of the nonadiabatic dynamics of water dimer. The effects of the initial vibrational state of the system on the electronic population transfer and dissociation dynamics are presented. To approximate the photochemical behavior of water dimer in bulk water, we add a boundary condition into the (2 + 1)-dimensional systems to simulate the existence of water bulk. The results provide insight into the mechanisms of excited state deactivation of the water-dimer system in gas phase and in bulk water through the electron-driven proton-transfer process.

  1. Two-dimensional Vlasov simulation of electron plasma wave trapping, wavefront bowing, self-focusing, and sideloss

    SciTech Connect (OSTI)

    Banks, J. W.; Berger, R. L.; Cohen, B. I.; Hittinger, J. A. F.; Brunner, S.

    2011-05-15

    Two-dimensional Vlasov simulations of nonlinear electron plasma waves are presented, in which the interplay of linear and nonlinear kinetic effects is evident. The plasma wave is created with an external traveling wave potential with a transverse envelope of width {Delta}y such that thermal electrons transit the wave in a ''sideloss'' time, t{sub sl{approx}{Delta}}y/v{sub e}. Here, v{sub e} is the electron thermal velocity. The quasisteady distribution of trapped electrons and its self-consistent plasma wave are studied after the external field is turned off. In cases of particular interest, the bounce frequency, {omega}{sub be}=k{radical}(e{phi}/m{sub e}), satisfies the trapping condition {omega}{sub be}t{sub sl}>2{pi} such that the wave frequency is nonlinearly downshifted by an amount proportional to the number of trapped electrons. Here, k is the wavenumber of the plasma wave and {phi} is its electric potential. For sufficiently short times, the magnitude of the negative frequency shift is a local function of {phi}. Because the trapping frequency shift is negative, the phase of the wave on axis lags the off-axis phase if the trapping nonlinearity dominates linear wave diffraction. In this case, the phasefronts are curved in a focusing sense. In the opposite limit, the phasefronts are curved in a defocusing sense. Analysis and simulations in which the wave amplitude and transverse width are varied establish criteria for the development of each type of wavefront. The damping and trapped-electron-induced focusing of the finite-amplitude electron plasma wave are also simulated. The damping rate of the field energy of the wave is found to be about the sideloss rate, {nu}{sub e{approx}}t{sub sl}{sup -1}. For large wave amplitudes or widths {Delta}y, a trapping-induced self-focusing of the wave is demonstrated.

  2. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A [LaFayette, CA

    2009-05-05

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  3. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A.; Bakulin, Andrey

    2009-10-13

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  4. Field trials results of guided wave tomography

    SciTech Connect (OSTI)

    Volker, Arno Zon, Tim van; Leden, Edwin van der

    2015-03-31

    Corrosion is one of the industries major issues regarding the integrity of assets. Guided wave travel time tomography is a method capable of providing an absolute wall thickness map. This method is currently making the transition from the laboratory to the field. For this purpose a dedicated data acquisition system and special purpose EMAT sensor rings have been developed. The system can be deployed for permanent monitoring and inspections. Field trials have been conducted on various pipes with different diameters, containing either liquid or gas. The main focus has been on pipe supports. The results demonstrate the successful operation of the technology in the field. Expected corrosion damage was clearly visible on the produced results enabling asset owner to make calculated decisions on the pipelines safety, maintenance and operations.

  5. Guided wave opto-acoustic device

    DOE Patents [OSTI]

    Jarecki, Jr., Robert L.; Rakich, Peter Thomas; Camacho, Ryan; Shin, Heedeuk; Cox, Jonathan Albert; Qiu, Wenjun; Wang, Zheng

    2016-02-23

    The various technologies presented herein relate to various hybrid phononic-photonic waveguide structures that can exhibit nonlinear behavior associated with traveling-wave forward stimulated Brillouin scattering (forward-SBS). The various structures can simultaneously guide photons and phonons in a suspended membrane. By utilizing a suspended membrane, a substrate pathway can be eliminated for loss of phonons that suppresses SBS in conventional silicon-on-insulator (SOI) waveguides. Consequently, forward-SBS nonlinear susceptibilities are achievable at about 3000 times greater than achievable with a conventional waveguide system. Owing to the strong phonon-photon coupling achievable with the various embodiments, potential application for the various embodiments presented herein cover a range of radiofrequency (RF) and photonic signal processing applications. Further, the various embodiments presented herein are applicable to applications operating over a wide bandwidth, e.g. 100 MHz to 50 GHz or more.

  6. ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION...

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

    & Publications ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) ADMINISTRATIVE RECORDS SCHEDULE 6: ACCOUNTABLE OFFICERS' ACCOUNTS RECORDS ADM 6 PDF...

  7. Fermilab | Tevatron | Tevatron Symposium | Travel and Lodging

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

    Travel and Lodging Directions to Fermilab Local Accommodations Map of Local Hotels Transportation Visa Information Wifi Access at Fermilab Other Useful Links

  8. Time

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

    3 4 5 6 7 8 9 10 Time with respect to the BNB Trigger Time [µs] 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Fractional Flash Count per 0.15 µs with respect to Cosmic Background Measured Cosmic Rate (Beam-Off) BNB Trigger Data (Beam-On) [4.51E18 POT]

  9. Time

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

    10 15 20 Time with respect to the NuMI Trigger Time [µs] 0.9 1.0 1.1 1.2 1.3 1.4 1.5 Fractional Flash Count per 0.5 µs with respect to Cosmic Background Measured Cosmic Rate (Beam-Off) NuMI Trigger Data (Beam-On) [4.83E18 POT]

  10. Errors in determination of soil water content using time-domain reflectometry caused by soil compaction around wave guides

    SciTech Connect (OSTI)

    Ghezzehei, T.A.

    2008-05-29

    Application of time domain reflectometry (TDR) in soil hydrology often involves the conversion of TDR-measured dielectric permittivity to water content using universal calibration equations (empirical or physically based). Deviations of soil-specific calibrations from the universal calibrations have been noted and are usually attributed to peculiar composition of soil constituents, such as high content of clay and/or organic matter. Although it is recognized that soil disturbance by TDR waveguides may have impact on measurement errors, to our knowledge, there has not been any quantification of this effect. In this paper, we introduce a method that estimates this error by combining two models: one that describes soil compaction around cylindrical objects and another that translates change in bulk density to evolution of soil water retention characteristics. Our analysis indicates that the compaction pattern depends on the mechanical properties of the soil at the time of installation. The relative error in water content measurement depends on the compaction pattern as well as the water content and water retention properties of the soil. Illustrative calculations based on measured soil mechanical and hydrologic properties from the literature indicate that the measurement errors of using a standard three-prong TDR waveguide could be up to 10%. We also show that the error scales linearly with the ratio of rod radius to the interradius spacing.

  11. NEUP Foreign Travel Request Form | Department of Energy

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

    Foreign Travel Request Form NEUP Foreign Travel Request Form NEUP Foreign Travel Request Form NEUP Foreign Travel Form 07_31_12.docx (62.57 KB) More Documents & Publications DOE F 551.1 NEUP Student Travel Request Form HQ FNVA Questionnaire

  12. Positioner with long travel in two dimensions

    DOE Patents [OSTI]

    Trumper, David L.; Williams, Mark E.

    1997-12-23

    A precision positioning system is provided which provides long travel in two of the linear dimensions, while using non-contact bearings for both a first subassembly which provides long travel in one of the linear dimension and a second subassembly which provides long travel in the second linear dimension. The first or upper subassembly is preferably a magnetic subassembly which, in addition to providing long travel, also compensates or positions in three rotary dimensions and in the third linear dimension. The second subassembly is preferably either an air bearing or magnetic subassembly and is normally used only to provide long travel. Angled surfaces may be provided for magnetic bearings and capacitive or other gap sensing probes may be mounted to the stage and ground flush with the bearing actuators to provide more precise gap measurements.

  13. A real-time laser feedback control method for the three-wave laser source used in the polarimeter-interferometer diagnostic on Joint-TEXT tokamak

    SciTech Connect (OSTI)

    Xiong, C. Y.; Chen, J. Li, Q.; Liu, Y.; Gao, L.

    2014-12-15

    A three-wave laser polarimeter-interferometer, equipped with three independent far-infrared laser sources, has been developed on Joint-TEXT (J-TEXT) tokamak. The diagnostic system is capable of high-resolution temporal and phase measurement of the Faraday angle and line-integrated density. However, for long-term operation (>10 min), the free-running lasers can lead to large drifts of the intermediate frequencies (∼100–∼500 kHz/10 min) and decay of laser power (∼10%–∼20%/10 min), which act to degrade diagnostic performance. In addition, these effects lead to increased maintenance cost and limit measurement applicability to long pulse/steady state experiments. To solve this problem, a real-time feedback control method of the laser source is proposed. By accurately controlling the length of each laser cavity, both the intermediate frequencies and laser power can be simultaneously controlled: the intermediate frequencies are controlled according to the pre-set values, while the laser powers are maintained at an optimal level. Based on this approach, a real-time feedback control system has been developed and applied on J-TEXT polarimeter-interferometer. Long-term (theoretically no time limit) feedback of intermediate frequencies (maximum change less than ±12 kHz) and laser powers (maximum relative power change less than ±7%) has been successfully achieved.

  14. Wave-wave interactions in solar type III radio bursts

    SciTech Connect (OSTI)

    Thejappa, G.; MacDowall, R. J.

    2014-02-11

    The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.

  15. RADIATION WAVE DETECTION

    DOE Patents [OSTI]

    Wouters, L.F.

    1960-08-30

    Radiation waves can be detected by simultaneously measuring radiation- wave intensities at a plurality of space-distributed points and producing therefrom a plot of the wave intensity as a function of time. To this end. a detector system is provided which includes a plurality of nuclear radiation intensity detectors spaced at equal radial increments of distance from a source of nuclear radiation. Means are provided to simultaneously sensitize the detectors at the instant a wave of radiation traverses their positions. the detectors producing electrical pulses indicative of wave intensity. The system further includes means for delaying the pulses from the detectors by amounts proportional to the distance of the detectors from the source to provide an indication of radiation-wave intensity as a function of time.

  16. Better World Club Travel Cool | Open Energy Information

    Open Energy Info (EERE)

    World Club Travel Cool Jump to: navigation, search Name: Better World Club Travel Cool Place: Portland, Oregon Zip: 97209 Product: Travel Cool is the eNewsletter of the Better...

  17. Time-resolved imaging of millimeter waves using visible continuum from the positive column of a Cs-Xe dc discharge

    SciTech Connect (OSTI)

    Gitlin, M. S.; Golovanov, V. V.; Spivakov, A. G.; Tsvetkov, A. I.; Zelenogorskiy, V. V.

    2010-03-15

    We present a high-sensitivity technique for time-resolved imaging of millimeter waves (MMWs) using the visible continuum (VC) from the positive column (PC) of a medium-pressure Cs-Xe dc discharge. For the MMW imaging application, a uniform plasma slab of the PC of a Cs-Xe discharge with 10x8 cm{sup 2} aperture and 2 cm in thickness was generated for 45 Torr xenon. The imaging technique is based on the fact that the intensity of the e-Xe bremsstrahlung continuum from the PC increases in the visible region when the electrons in the plasma are heated by MMWs. It is shown that in the MMW intensity range from zero to the threshold of the microwave-induced plasma breakdown, the intensity of the VC from the PC of a Cs-Xe discharge increases approximately as a second-order polynomial function of the MMW intensity. The obtained experimental data agree well with our calculations of the dependence of the VC intensity on electron temperature. The Ka-band MMW field patterns at the output of conical horn antennas and in the quasioptical beam were imaged using the discharge technique. It is shown that the technique can be used for time-resolved measurement of the profiles of watt- and subwatt-level MMWs. An energy flux sensitivity of the technique of about 10 {mu}J/cm{sup 2} in the Ka-band was demonstrated. The temporal resolution of the technique is about 0.8 {mu}s. Our modeling of the transient behavior of the electron temperature in the PC shows that the time history of the electron temperature variation coincides well with the measured time history of the VC intensity variation.

  18. Venue and Travel | Department of Energy

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

    Venue and Travel Venue and Travel Venue and Travel Hilton Anaheim 777 W Convention Way Anaheim, California, 92802 USA TEL: 1-714-750-4321 FAX: 1-714-740-4460 Reserving Your Room For your convenience, a limited room block has been set up at the group rate of $133 per night (plus applicable taxes). Space is limited and will sell out fast. Reservations can be made via the call center 1-877-776-4932 using the group code: SGE or you can book online: SunShot Grand Challenge Summit Room Block.

  19. ORISE: CDC Travelers' Health Mobile App, Designed by ORISE, Gains...

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

    choices while traveling internationally and tasked ORISE with designing iPhone and Android versions. "Nothing is more important to us than the health and safety of travelers,...

  20. DOE Energy Taxation Forum - Travel Fact Sheet | Department of...

    Office of Environmental Management (EM)

    Travel Fact Sheet DOE Energy Taxation Forum - Travel Fact Sheet PDF icon TFS Tax Forum New Orleans 02272012.pdf More Documents & Publications DOE Energy Taxation Forum -...

  1. Hotel and Travel Information for the Summit

    Broader source: Energy.gov [DOE]

    The Executive Summit on Wind Research and Development is being held in the Cottonwoods Pavillion at the Hyatt Regency Tamaya Resort and Spa. Here registrants can find summit hotel and travel...

  2. Quantifying the Effect of Fast Charger Deployments on Electric Vehicle Utility and Travel Patterns via Advanced Simulation: Preprint

    SciTech Connect (OSTI)

    Wood, E.; Neubauer, J.; Burton, E.

    2015-02-01

    The disparate characteristics between conventional (CVs) and battery electric vehicles (BEVs) in terms of driving range, refill/recharge time, and availability of refuel/recharge infrastructure inherently limit the relative utility of BEVs when benchmarked against traditional driver travel patterns. However, given a high penetration of high-power public charging combined with driver tolerance for rerouting travel to facilitate charging on long-distance trips, the difference in utility between CVs and BEVs could be marginalized. We quantify the relationships between BEV utility, the deployment of fast chargers, and driver tolerance for rerouting travel and extending travel durations by simulating BEVs operated over real-world travel patterns using the National Renewable Energy Laboratory's Battery Lifetime Analysis and Simulation Tool for Vehicles (BLAST-V). With support from the U.S. Department of Energy's Vehicle Technologies Office, BLAST-V has been developed to include algorithms for estimating the available range of BEVs prior to the start of trips, for rerouting baseline travel to utilize public charging infrastructure when necessary, and for making driver travel decisions for those trips in the presence of available public charging infrastructure, all while conducting advanced vehicle simulations that account for battery electrical, thermal, and degradation response. Results from BLAST-V simulations on vehicle utility, frequency of inserted stops, duration of charging events, and additional time and distance necessary for rerouting travel are presented to illustrate how BEV utility and travel patterns can be affected by various fast charge deployments.

  3. Rebound 2007: Analysis of U.S. Light-Duty Vehicle Travel Statistics

    SciTech Connect (OSTI)

    Greene, David L

    2010-01-01

    U.S. national time series data on vehicle travel by passenger cars and light trucks covering the period 1966 2007 are used to test for the existence, size and stability of the rebound effect for motor vehicle fuel efficiency on vehicle travel. The data show a statistically significant effect of gasoline price on vehicle travel but do not support the existence of a direct impact of fuel efficiency on vehicle travel. Additional tests indicate that fuel price effects have not been constant over time, although the hypothesis of symmetry with respect to price increases and decreases is not rejected. Small and Van Dender (2007) model of a declining rebound effect with income is tested and similar results are obtained.

  4. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

  5. Thurston Regional Planning Council Helps Washingtonians Save on Travel Costs

    Broader source: Energy.gov [DOE]

    Thurston County provides travel information for lower costs, improved safety, and faster response to challenges.

  6. PIA - Foreign Travel Management System (FTMS) | Department of Energy

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

    Travel Management System (FTMS) PIA - Foreign Travel Management System (FTMS) PIA - Foreign Travel Management System (FTMS) PIA - Foreign Travel Management System (FTMS) (389.71 KB) More Documents & Publications PIA - INL PeopleSoft - Human Resource System PIA - INL SECURITY INFORMATION MANAGEMENT SYSTEM BUSINESS ENCLAVE

  7. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, Stanley P. (Los Alamos, NM)

    1988-01-01

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive.

  8. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1988-03-08

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

  9. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1987-03-12

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

  10. The detection of upwardly propagating waves channeling energy from the chromosphere to the low corona

    SciTech Connect (OSTI)

    Freij, N.; Nelson, C. J.; Mumford, S.; Erdlyi, R.; Scullion, E. M.; Wedemeyer, S.

    2014-08-10

    There have been ubiquitous observations of wave-like motions in the solar atmosphere for decades. Recent improvements to space- and ground-based observatories have allowed the focus to shift to smaller magnetic structures on the solar surface. In this paper, high-resolution ground-based data taken using the Swedish 1 m Solar Telescope is combined with co-spatial and co-temporal data from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) satellite to analyze running penumbral waves (RPWs). RPWs have always been thought to be radial wave propagation that occurs within sunspots. Recent research has suggested that they are in fact upwardly propagating field-aligned waves (UPWs). Here, RPWs within a solar pore are observed for the first time and are interpreted as UPWs due to the lack of a penumbra that is required to support RPWs. These UPWs are also observed co-spatially and co-temporally within several SDO/AIA elemental lines that sample the transition region and low corona. The observed UPWs are traveling at a horizontal velocity of around 17 0.5 km s{sup 1} and a minimum vertical velocity of 42 21 km s{sup 1}. The estimated energy of the waves is around 150 W m{sup 2}, which is on the lower bound required to heat the quiet-Sun corona. This is a new, yet unconsidered source of wave energy within the solar chromosphere and low corona.

  11. Frequency-dependent damping in propagating slow magneto-acoustic waves

    SciTech Connect (OSTI)

    Prasad, S. Krishna; Banerjee, D.; Van Doorsselaere, T.

    2014-07-10

    Propagating slow magneto-acoustic waves are often observed in polar plumes and active region fan loops. The observed periodicities of these waves range from a few minutes to a few tens of minutes and their amplitudes were found to decay rapidly as they travel along the supporting structure. Previously, thermal conduction, compressive viscosity, radiation, density stratification, and area divergence were identified to be some of the causes for change in the slow wave amplitude. Our recent studies indicate that the observed damping in these waves is frequency-dependent. We used imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly to study this dependence in detail and for the first time via observations we attempted to deduce a quantitative relation between the damping length and frequency of these oscillations. We developed a new analysis method to obtain this relation. The observed frequency dependence does not seem to agree with the current linear wave theory and it was found that the waves observed in the polar regions show a different dependence from those observed in the on-disk loop structures despite the similarity in their properties.

  12. Transferring 2001 National Household Travel Survey

    SciTech Connect (OSTI)

    Hu, Patricia S; Reuscher, Tim; Schmoyer, Richard L; Chin, Shih-Miao

    2007-05-01

    Policy makers rely on transportation statistics, including data on personal travel behavior, to formulate strategic transportation policies, and to improve the safety and efficiency of the U.S. transportation system. Data on personal travel trends are needed to examine the reliability, efficiency, capacity, and flexibility of the Nation's transportation system to meet current demands and to accommodate future demand. These data are also needed to assess the feasibility and efficiency of alternative congestion-mitigating technologies (e.g., high-speed rail, magnetically levitated trains, and intelligent vehicle and highway systems); to evaluate the merits of alternative transportation investment programs; and to assess the energy-use and air-quality impacts of various policies. To address these data needs, the U.S. Department of Transportation (USDOT) initiated an effort in 1969 to collect detailed data on personal travel. The 1969 survey was the first Nationwide Personal Transportation Survey (NPTS). The survey was conducted again in 1977, 1983, 1990, 1995, and 2001. Data on daily travel were collected in 1969, 1977, 1983, 1990 and 1995. In 2001, the survey was renamed the National Household Travel Survey (NHTS) and it collected both daily and long-distance trips. The 2001 survey was sponsored by three USDOT agencies: Federal Highway Administration (FHWA), Bureau of Transportation Statistics (BTS), and National Highway Traffic Safety Administration (NHTSA). The primary objective of the survey was to collect trip-based data on the nature and characteristics of personal travel so that the relationships between the characteristics of personal travel and the demographics of the traveler can be established. Commercial and institutional travel were not part of the survey. Due to the survey's design, data in the NHTS survey series were not recommended for estimating travel statistics for categories smaller than the combination of Census division (e.g., New England, Middle

  13. Light-Duty Vehicle Energy Demand, Demographics, and Travel Behavior

    U.S. Energy Information Administration (EIA) Indexed Site

    EIA Conference July 15, 2014 | Washington, DC By Trisha Hutchins, Office of Energy Consumption and Efficiency Analysis Light-duty vehicle energy demand, demographics, and travel behavior Examining changes in light-duty vehicle travel trends 2 EIA Conference: Light-duty vehicle energy demand, demographics, and travel behavior July 15, 2014 * Recent data indicate possible structural shift in travel behavior, measured as vehicle miles traveled (VMT) - VMT per licensed driver, vehicles per capita,

  14. Foreign Travel Health & Wellness Information | Department of Energy

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

    Wellness Programs » Foreign Travel Health & Wellness Information Foreign Travel Health & Wellness Information All travelers should take the following precautions, no matter the destination: Wash hands often with soap and water. Because motor vehicle crashes are a leading cause of injury among travelers, walk and drive defensively; avoid travel at night if possible and always use seat belts. Don't eat or drink dairy products unless you know they have been pasteurized. Never eat

  15. A neural network for real-time retrievals of PWV and LWP from Arctic millimeter-wave ground-based observations.

    SciTech Connect (OSTI)

    Cadeddu, M. P.; Turner, D. D.; Liljegren, J. C.; Decision and Information Sciences; Univ. of Wisconsin at Madison

    2009-07-01

    This paper presents a new neural network (NN) algorithm for real-time retrievals of low amounts of precipitable water vapor (PWV) and integrated liquid water from millimeter-wave ground-based observations. Measurements are collected by the 183.3-GHz G-band vapor radiometer (GVR) operating at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility, Barrow, AK. The NN provides the means to explore the nonlinear regime of the measurements and investigate the physical boundaries of the operability of the instrument. A methodology to compute individual error bars associated with the NN output is developed, and a detailed error analysis of the network output is provided. Through the error analysis, it is possible to isolate several components contributing to the overall retrieval errors and to analyze the dependence of the errors on the inputs. The network outputs and associated errors are then compared with results from a physical retrieval and with the ARM two-channel microwave radiometer (MWR) statistical retrieval. When the NN is trained with a seasonal training data set, the retrievals of water vapor yield results that are comparable to those obtained from a traditional physical retrieval, with a retrieval error percentage of {approx}5% when the PWV is between 2 and 10 mm, but with the advantages that the NN algorithm does not require vertical profiles of temperature and humidity as input and is significantly faster computationally. Liquid water path (LWP) retrievals from the NN have a significantly improved clear-sky bias (mean of {approx}2.4 g/m{sup 2}) and a retrieval error varying from 1 to about 10 g/m{sup 2} when the PWV amount is between 1 and 10 mm. As an independent validation of the LWP retrieval, the longwave downwelling surface flux was computed and compared with observations. The comparison shows a significant improvement with respect to the MWR statistical retrievals, particularly for LWP amounts of less than 60 g/m{sup 2}.

  16. Regional Seismic Travel Time Node Get and Set

    Energy Science and Technology Software Center (OSTI)

    2012-10-24

    RSTT_NOGS allows users to easily get and set seismic velocity vs. depth profiles at specified model tessellation nodes. RSTT_NOGS uses the Sandia Seismic Location Baseline Model code that was released under BSD license in 2009.

  17. New Hire Relocation Travel Information Guide

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

    New Hire Relocation Travel Information Guide This information guide is provided by the CFO Travel Relocation Office to assist you in planning your relocation to Los Alamos. Please contact the Relocation Office at least two to four weeks prior to your relocation to discuss your relocation plans. You can contact the Relocation Office at (505) 665-4484 or by e-mail at relocation@lanl.gov. You must have met all contingencies, if any, of your hire as well as have proper work authorization before the

  18. Analysis of plug-in hybrid electric vehicles' utility factors using GPS-based longitudinal travel data

    SciTech Connect (OSTI)

    Wu, Xing; Aviquzzaman, Md.; Lin, Zhenhong

    2015-05-29

    The benefit of using a PHEV comes from its ability to substitute gasoline with electricity in operation. Defined as the proportion of distance traveled in the electric mode, the utility factor (UF) depends mostly on the battery capacity, but also on many other factors, such as travel pattern and recharging pattern. Conventionally, the UFs are calculated based on the daily vehicle miles traveled (DVMT) by assuming motorists leave home in the morning with a full battery, and no charge occurs before returning home in the evening. Such an assumption, however, ignores the impact of the heterogeneity in both travel and charging behavior, such as going back home more than once in a day, the impact of available charging time, and the price of gasoline. In addition, the conventional UFs are based on the National Household Travel Survey (NHTS) data, which are one-day travel data of each sample vehicle. A motorist's daily distance variation is ignored. This paper employs the GPS-based longitudinal travel data (covering 3-18 months) collected from 403 vehicles in the Seattle metropolitan area to investigate how such travel and charging behavior affects UFs. To do this, for each vehicle, we organized trips to a series of home and work related tours. The UFs based on the DVMT are found close to those based on home-to-home tours. However, it is seen that the workplace charge opportunities significantly increase UFs if the CD range is no more than 40 miles.

  19. Analysis of plug-in hybrid electric vehicles' utility factors using GPS-based longitudinal travel data

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wu, Xing; Aviquzzaman, Md.; Lin, Zhenhong

    2015-05-29

    The benefit of using a PHEV comes from its ability to substitute gasoline with electricity in operation. Defined as the proportion of distance traveled in the electric mode, the utility factor (UF) depends mostly on the battery capacity, but also on many other factors, such as travel pattern and recharging pattern. Conventionally, the UFs are calculated based on the daily vehicle miles traveled (DVMT) by assuming motorists leave home in the morning with a full battery, and no charge occurs before returning home in the evening. Such an assumption, however, ignores the impact of the heterogeneity in both travel andmore » charging behavior, such as going back home more than once in a day, the impact of available charging time, and the price of gasoline. In addition, the conventional UFs are based on the National Household Travel Survey (NHTS) data, which are one-day travel data of each sample vehicle. A motorist's daily distance variation is ignored. This paper employs the GPS-based longitudinal travel data (covering 3-18 months) collected from 403 vehicles in the Seattle metropolitan area to investigate how such travel and charging behavior affects UFs. To do this, for each vehicle, we organized trips to a series of home and work related tours. The UFs based on the DVMT are found close to those based on home-to-home tours. However, it is seen that the workplace charge opportunities significantly increase UFs if the CD range is no more than 40 miles.« less

  20. Entropic information for travelling solitons in Lorentz and CPT breaking systems

    SciTech Connect (OSTI)

    Correa, R.A.C.; Rocha, Roldão da; Souza Dutra, A. de

    2015-08-15

    In this work we group four research topics apparently disconnected, namely solitons, Lorentz symmetry breaking, supersymmetry, and entropy. Following a recent work (Gleiser and Stamatopoulos, 2012), we show that it is possible to construct in the context of travelling wave solutions a configurational entropy measure in functional space, from the field configurations. Thus, we investigate the existence and properties of travelling solitons in Lorentz and CPT breaking scenarios for a class of models with two interacting scalar fields. Here, we obtain a complete set of exact solutions for the model studied which display both double and single-kink configurations. In fact, such models are very important in applications that include Bloch branes, Skyrmions, Yang–Mills, Q-balls, oscillons and various superstring-motivated theories. We find that the so-called Configurational Entropy (CE) for travelling solitons shows that the best value of parameter responsible to break the Lorentz symmetry is one where the energy density is distributed equally around the origin. In this way, the information-theoretical measure of travelling solitons in Lorentz symmetry violation scenarios opens a new window to probe situations where the parameters responsible for breaking the symmetries are arbitrary. In this case, the CE selects the best value of the parameter in the model.

  1. Fracture identification and evaluation using borehole imaging and full wave form logs in the Permian basin

    SciTech Connect (OSTI)

    Sanders, L. )

    1994-03-01

    The borehole imaging and acoustic full wave form logs provide an excellent means for identifying and evaluating naturally occurring fractures. The natural fractures can provide the porosity and permeability essential for a productive reservoir. The detection of these fractures may be accomplished by tow types of wireline logging tools: borehole imaging devices and acoustic full wave form tools. The borehole imaging tools produce images based upon the electromagnetic or the acoustic properties of the borehole wall. Fractures will appear as darker images that are distinct from the nonfracture formation. These images are coupled with a reference azimuth that allows for the determination of the orientation of the fracture image. The acoustic full wave form logs are used to detect fractures by analyzing various acoustic properties of the formation. The travel time, amplitude, and frequency responses of fractured formations differ remarkably from the responses of nonfractured formations because of the reduction of the acoustic energy in the fractures. The various field examples from the Queen sandstone to the Ellenburger formation demonstrate the advantages and disadvantages unique to the borehole imaging and the acoustic full wave form devices. Within this geologic framework, comparisons are made among the data extracted from whole cores, borehole imaging devices, and the acoustic full wave form tools in establishing a systematic approach for the identification and evaluation of fractures.

  2. RADIATION WAVE DETECTOR

    DOE Patents [OSTI]

    Wouters, L.F.

    1958-10-28

    The detection of the shape and amplitude of a radiation wave is discussed, particularly an apparatus for automatically indicating at spaced lntervals of time the radiation intensity at a flxed point as a measure of a radiation wave passing the point. The apparatus utilizes a number of photomultiplier tubes surrounding a scintillation type detector, For obtainlng time spaced signals proportional to radiation at predetermined intervals the photolnultiplier tubes are actuated ln sequence following detector incidence of a predetermined radiation level by electronic means. The time spaced signals so produced are then separately amplified and relayed to recording means.

  3. Travel Services Transition to Omega World Travel to Begin on July 29 |

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

    Jefferson Lab on August 2 in the CEBAF Center auditorium. Be sure to monitor your email for further information on the transition and cut-over. If you have any questions about the transition, please contact Travel Services at757-269-7192. For more information, see the original announcement: https://www.jlab.org/memo/omega-world-travel-will-be-taking-over-subcontract

  4. Travel Services Transition to Omega World Travel to Begin on July 29 |

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

    Jefferson Lab on August 2 in the CEBAF Center auditorium. Be sure to monitor your email for further information on the transition and cut-over. If you have any questions about the transition, please contact Travel Services at757-269-7192. For more information, see the original announcement: https://www.jlab.org/memo/omega-world-travel-will-be-taking-over-subcont...

  5. Researchers test novel power system for space travel

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

    Power system for space travel Researchers test novel power system for space travel The ... "The heat pipe and Stirling engine used in this test are meant to represent one module ...

  6. Symmetries of the triple degenerate DNLS equations for weakly nonlinear dispersive MHD waves

    SciTech Connect (OSTI)

    Webb, G. M.; Brio, M.; Zank, G. P.

    1996-07-20

    A formulation of Hamiltonian and Lagrangian variational principles, Lie point symmetries and conservation laws for the triple degenerate DNLS equations describing the propagation of weakly nonlinear dispersive MHD waves along the ambient magnetic field, in {beta}{approx}1 plasmas is given. The equations describe the interaction of the Alfven and magnetoacoustic modes near the triple umbilic point, where the fast magnetosonic, slow magnetosonic and Alfven speeds coincide and a{sub g}{sup 2}=V{sub A}{sup 2} where a{sub g} is the gas sound speed and V{sub A} is the Alfven speed. A discussion is given of the travelling wave similarity solutions of the equations, which include solitary wave and periodic traveling waves. Strongly compressible solutions indicate the necessity for the insertion of shocks in the flow, whereas weakly compressible, near Alfvenic solutions resemble similar, shock free travelling wave solutions of the DNLS equation.

  7. Checklist for Medical Issues When Traveling Overseas | Department of Energy

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

    Benefits » Wellness Programs » Foreign Travel Health & Wellness Information » Checklist for Medical Issues When Traveling Overseas Checklist for Medical Issues When Traveling Overseas Before the Trip A written confirmation from an appropriate manager, i.e., a Travel Authorization or memorandum, that identifies the employee and country(ies) that will be visited should be provided the medical support staff 4-8 weeks prior to the trip or, if less than 4 weeks, as soon as management or the

  8. ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS

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

    (Revision 2) | Department of Energy 9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) This schedule covers records documenting the movement of goods and persons under Government orders. ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS (Revision 2) (14.5 KB) More Documents & Publications ADMINISTRATIVE RECORDS SCHEDULE 9: TRAVEL AND TRANSPORTATION RECORDS ADMINISTRATIVE RECORDS SCHEDULE

  9. Connected Traveler (Fact Sheet), NREL (National Renewable Energy Laboratory)

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

    Source: Texas A&M Transportation Institute, 2015 Urban Mobility Scorecard MARKET OPPORTUNITY Increased Mobility Meets Emission Reductions Traveler Vehicle Transport System Built Environment Starting with the Traveler The Connected Traveler approach looks at sustainable transportation as a network of travelers, services, and decision points connected by communication technology and decision-making tools-rather than just by vehicles and roads-to signifcantly reduce related energy consumption

  10. A statistical study of EMIC waves observed by Cluster. 1. Wave properties. EMIC Wave Properties

    SciTech Connect (OSTI)

    Allen, R. C.; Zhang, J. -C.; Kistler, L. M.; Spence, H. E.; Lin, R. -L.; Klecker, B.; Dunlop, M. W.; André, M.; Jordanova, V. K.

    2015-07-23

    Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L-shell (MLT-L) frame within a limited magnetic latitude (MLAT) range. In our study, we present a statistical analysis of EMIC wave properties using 10 years (2001–2010) of data from Cluster, totaling 25,431 min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. Thus, the statistical analysis is presented in two papers. OUr paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.

  11. A statistical study of EMIC waves observed by Cluster. 1. Wave properties. EMIC Wave Properties

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Allen, R. C.; Zhang, J. -C.; Kistler, L. M.; Spence, H. E.; Lin, R. -L.; Klecker, B.; Dunlop, M. W.; André, M.; Jordanova, V. K.

    2015-07-23

    Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L-shell (MLT-L) frame within a limited magnetic latitude (MLAT) range. In our study, we present a statistical analysis of EMIC wave properties using 10 years (2001–2010) of datamore » from Cluster, totaling 25,431 min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. Thus, the statistical analysis is presented in two papers. OUr paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.« less

  12. A statistical study of EMIC waves observed by Cluster. 1. Wave properties. EMIC Wave Properties

    SciTech Connect (OSTI)

    Allen, R. C.; Zhang, J. -C.; Kistler, L. M.; Spence, H. E.; Lin, R. -L.; Klecker, B.; Dunlop, M. W.; Andr, M.; Jordanova, V. K.

    2015-07-23

    Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L-shell (MLT-L) frame within a limited magnetic latitude (MLAT) range. In our study, we present a statistical analysis of EMIC wave properties using 10 years (20012010) of data from Cluster, totaling 25,431 min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. Thus, the statistical analysis is presented in two papers. OUr paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.

  13. Jefferson Lab Visitor's Center - Travel Accommodations

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

    Travel Accommodations While visiting or working at JLab there are many options for living accommodations. These options vary depending upon the expected length of stay, transportation available and money allotted for housing expenses. The following information has been compiled to assist in the search for living accommodations near the lab. For further assistance e-mail User Liaison or call 757-269-6388. On-Site Accommodations SURA Residence Facility Off-Site Accommodations Negotiated Lodging

  14. Extension arm for mobile travelers suit case

    DOE Patents [OSTI]

    Byington, Gerald A.

    1999-01-01

    The invention is an apparatus for adjusting a luggage handle in relation to a luggage frame utilized to transport luggage by a traveler. The handle is connected to two extendable and retractable slide tube assemblies, the assemblies allow for the telescoping of the luggage handle to multiple positions in relation to a pair of fixed frame tubes connected to a luggage shell with wheels, to accommodate the height and personal stride of traveler. The luggage handle incorporates triggering buttons that allow ambidextrous and single-handed control of the height of the handle and slide tube assembly in relation to the luggage. The handle and slide tube assembly are connected by interior filaments to pulleys and filaments within two concentric light-weight slide tubes, which are inserted respectively into two fixed frame tubes, to allow a multitude of positions for the slide tubes to lock into the fixed frame tubes. The apparatus can be pushed or pulled by the traveler, and the support shell can accommodate multiple pieces of luggage.

  15. MHK Technologies/Ocean Wave Energy Converter OWEC | Open Energy...

    Open Energy Info (EERE)

    with fewer parts Electromechanical loads are real time adjustable with respect to wave sensor web resulting in optimal energy conversion from near fully submerged wave following...

  16. CONNECTING THE SUN AND THE SOLAR WIND: THE FIRST 2.5-DIMENSIONAL SELF-CONSISTENT MHD SIMULATION UNDER THE ALFVEN WAVE SCENARIO

    SciTech Connect (OSTI)

    Matsumoto, Takuma; Suzuki, Takeru Ken

    2012-04-10

    The solar wind emanates from the hot and tenuous solar corona. Earlier studies using 1.5-dimensional simulations show that Alfven waves generated in the photosphere play an important role in coronal heating through the process of nonlinear mode conversion. In order to understand the physics of coronal heating and solar wind acceleration together, it is important to consider the regions from photosphere to interplanetary space as a single system. We performed 2.5-dimensional, self-consistent magnetohydrodynamic simulations, covering from the photosphere to the interplanetary space for the first time. We carefully set up the grid points with spherical coordinates to treat the Alfven waves in the atmosphere with huge density contrast and successfully simulate the solar wind streaming out from the hot solar corona as a result of the surface convective motion. The footpoint motion excites Alfven waves along an open magnetic flux tube, and these waves traveling upward in the non-uniform medium undergo wave reflection, nonlinear mode conversion from Alfven mode to slow mode, and turbulent cascade. These processes lead to the dissipation of Alfven waves and acceleration of the solar wind. It is found that the shock heating by the dissipation of the slow-mode wave plays a fundamental role in the coronal heating process, whereas the turbulent cascade and shock heating drive the solar wind.

  17. Omega World Travel will be taking over the subcontract | Jefferson Lab

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

    will be taking over the subcontract JLab's Travel Agency Contract: Omega World Travel will be taking over the subcontract by Aug. 1, 2016 Jefferson Lab's Travel Agency contract was recently sent out for rebid. We are pleased to announce that Omega World Travel was awarded the subcontract as the Lab's official travel agency. We plan to go live using Omega World Travel by August 1st. In the interim, MAKE NO CHANGES - continue to utilize CIAZ Travel for all travel arrangements until further

  18. A mm-wave planar microcavity structure for electron linear accelerator system

    SciTech Connect (OSTI)

    Kang, Y.W.; Kustom, R.; Mills, F.; Mavrogenes, G.; Henke, H.

    1993-07-01

    The muffin-tin cavity structure is planar and well suited for mm-wave accelerator with silicon etching techniques. A constant impedance traveling-wave structure is considered for design simplicity. The RF parameters are calculated and the shunt impedance is compared with the shunt impedance of a disk loaded cylindrical structure.

  19. Stochastic simulation for the propagation of high-frequency acoustic waves through a random velocity field

    SciTech Connect (OSTI)

    Lu, B.; Darmon, M.; Leymarie, N.; Chatillon, S.; Potel, C.

    2012-05-17

    In-service inspection of Sodium-Cooled Fast Reactors (SFR) requires the development of non-destructive techniques adapted to the harsh environment conditions and the examination complexity. From past experiences, ultrasonic techniques are considered as suitable candidates. The ultrasonic telemetry is a technique used to constantly insure the safe functioning of reactor inner components by determining their exact position: it consists in measuring the time of flight of the ultrasonic response obtained after propagation of a pulse emitted by a transducer and its interaction with the targets. While in-service the sodium flow creates turbulences that lead to temperature inhomogeneities, which translates into ultrasonic velocity inhomogeneities. These velocity variations could directly impact the accuracy of the target locating by introducing time of flight variations. A stochastic simulation model has been developed to calculate the propagation of ultrasonic waves in such an inhomogeneous medium. Using this approach, the travel time is randomly generated by a stochastic process whose inputs are the statistical moments of travel times known analytically. The stochastic model predicts beam deviations due to velocity inhomogeneities, which are similar to those provided by a determinist method, such as the ray method.

  20. Preliminary result of P-wave speed tomography beneath North Sumatera region

    SciTech Connect (OSTI)

    Jatnika, Jajat; Nugraha, Andri Dian; Wandono

    2015-04-24

    The structure of P-wave speed beneath the North Sumatra region was determined using P-wave arrival times compiled by MCGA from time periods of January 2009 to December 2012 combining with PASSCAL data for February to May 1995. In total, there are 2,246 local earthquake events with 10,666 P-wave phases from 63 stations seismic around the study area. Ray tracing to estimate travel time from source to receiver in this study by applying pseudo-bending method while the damped LSQR method was used for the tomographic inversion. Based on assessment of ray coverage, earthquakes and stations distribution, horizontal grid nodes was set up of 3030 km2 for inside the study area and 8080 km2 for outside the study area. The tomographic inversion results show low Vp anomaly beneath Toba caldera complex region and around the Sumatra Fault Zones (SFZ). These features are consistent with previous study. The low Vp anomaly beneath Toba caldera complex are observed around Mt. Pusuk Bukit at depths of 5?km down to 100?km. The interpretation is these anomalies may be associated with ascending hot materials from subduction processes at depths of 80?km down to 100?km. The obtained Vp structure from local tomography will give valuable information to enhance understanding of tectonic and volcanic in this study area.

  1. Pressure waves in liquid mercury target from pulsed heat loads and the possible way controlling their effects

    SciTech Connect (OSTI)

    Ni, L.; Skala, K.

    1996-06-01

    In ESS project liquid metals are selected as the main target for the pulsed spallation neutron source. Since the very high instantaneous energy is deposited on the heavy molten target in a very short period time, pressure waves are generated. They travel through the liquid and cause high stress in the container. Also, additional stress should be considered in the wall which is the result of direct heating of the target window. These dynamic processes were simulated with computational codes with the static response being analized first. The total resulting dynamic wall stress has been found to have exceeded the design stress for the selected container material. Adding a small amount of gas bubbles in the liquid could be a possible way to reduce the pressure waves.

  2. Marine pipeline dynamic response to waves from directional wave spectra

    SciTech Connect (OSTI)

    Lambrakos, K.F.

    1982-07-01

    A methodology has been developed to calculate the dynamic probabilistic movement and resulting stresses for marine pipelines subjected to storm waves. A directional wave spectrum is used with a Fourier series expansion to simulate short-crested waves and calculate their loads on the pipeline. The pipeline displacements resulting from these loads are solutions to the time-dependent beam-column equation which also includes the soil resistance as external loading. The statistics of the displacements for individual waves are combined with the wave statistics for a given period of time, e.g. pipeline lifetime, to generate probabilistic estimates for net pipeline movement. On the basis of displacements for specified probability levels the pipeline configuration is obtained from which pipeline stresses can be estimated using structural considerations, e.g. pipeline stiffness, end restraints, etc.

  3. Quantum positron acoustic waves

    SciTech Connect (OSTI)

    Metref, Hassina; Tribeche, Mouloud

    2014-12-15

    Nonlinear quantum positron-acoustic (QPA) waves are investigated for the first time, within the theoretical framework of the quantum hydrodynamic model. In the small but finite amplitude limit, both deformed Korteweg-de Vries and generalized Korteweg-de Vries equations governing, respectively, the dynamics of QPA solitary waves and double-layers are derived. Moreover, a full finite amplitude analysis is undertaken, and a numerical integration of the obtained highly nonlinear equations is carried out. The results complement our previously published results on this problem.

  4. THE EFFECTS OF WAVE ESCAPE ON FAST MAGNETOSONIC WAVE TURBULENCE IN SOLAR FLARES

    SciTech Connect (OSTI)

    Pongkitiwanichakul, Peera; Chandran, Benjamin D. G.; Karpen, Judith T.; DeVore, C. Richard E-mail: benjamin.chandran@unh.edu E-mail: devore@nrl.navy.mil

    2012-09-20

    One of the leading models for electron acceleration in solar flares is stochastic acceleration by weakly turbulent fast magnetosonic waves ({sup f}ast waves{sup )}. In this model, large-scale flows triggered by magnetic reconnection excite large-wavelength fast waves, and fast-wave energy then cascades from large wavelengths to small wavelengths. Electron acceleration by large-wavelength fast waves is weak, and so the model relies on the small-wavelength waves produced by the turbulent cascade. In order for the model to work, the energy cascade time for large-wavelength fast waves must be shorter than the time required for the waves to propagate out of the solar-flare acceleration region. To investigate the effects of wave escape, we solve the wave kinetic equation for fast waves in weak turbulence theory, supplemented with a homogeneous wave-loss term. We find that the amplitude of large-wavelength fast waves must exceed a minimum threshold in order for a significant fraction of the wave energy to cascade to small wavelengths before the waves leave the acceleration region. We evaluate this threshold as a function of the dominant wavelength of the fast waves that are initially excited by reconnection outflows.

  5. Sec. Chu Travels to Houston | Department of Energy

    Office of Environmental Management (EM)

    Secretary Chu traveled to Houston, Texas, today to meet with executives from various oil ... This strategy is focused on safely and responsibly developing our oil and gas resources ...

  6. DOE Honors WIPP Representative for Cutting Travel Costs, Greenhouse...

    Office of Environmental Management (EM)

    document reviews with regulators instead of meeting in person and reduced rental car usage by standardizing travel arrangements so that only one rental car is necessary per...

  7. Secretary Bodman Travels to Saudi Arabia to Discuss Global Energy...

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

    business leaders in Jordan. He will also travel to the United Arab Emirates, Qatar, and Egypt, to continue dialogues with global leaders, enhance the United States' relationship...

  8. Travelers Rest, South Carolina: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Travelers Rest, South Carolina: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 34.9676167, -82.4434548 Show Map Loading map......

  9. Statement by DOE Spokesperson on Secretary Moniz's Travel to...

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

    travel to Geneva on Saturday to join Secretary Kerry in continued negotiations with Iran over its nuclear program. Department of Energy officials have consistently been...

  10. Petroleum Reduction Strategies to Reduce Vehicle Miles Traveled

    Broader source: Energy.gov [DOE]

    For reducing greenhouse gas emissions, the table below describes petroleum reduction strategies to reduce vehicle miles traveled, as well as guidance and best practices for each strategy.

  11. Solar Decathlon: How far did they travel? | Department of Energy

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

    Decathlon Journeys Visualizing the distances that each Solar Decathlon house travelled Click competitors to toggle their journeys on and off. All routes and distances are...

  12. NNSA Administrator D'Agostino's Safeguards Conference Travel...

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

    Conference Travel Blog Follow the second international meeting in Tokai-mura, Ibaraki Japan This week, NNSA Administrator Thomas D'Agostino attended the second international...

  13. NNSA Administrator D'Agostino's 2009 IAEA Travel Blog | National...

    National Nuclear Security Administration (NNSA)

    09 IAEA Travel Blog | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the...

  14. NO FLARES FROM GAMMA-RAY BURST AFTERGLOW BLAST WAVES ENCOUNTERING SUDDEN CIRCUMBURST DENSITY CHANGE

    SciTech Connect (OSTI)

    Gat, Ilana; Van Eerten, Hendrik; MacFadyen, Andrew [Center for Cosmology and Particle Physics, Physics Department, New York University, New York, NY 10003 (United States)

    2013-08-10

    Afterglows of gamma-ray bursts are observed to produce light curves with the flux following power-law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days. One proposed explanation for these flares is the interaction of a relativistic blast wave with a circumburst density transition. In this paper, we model this type of interaction computationally in one and two dimensions, using a relativistic hydrodynamics code with adaptive mesh refinement called RAM, and analytically in one dimension. We simulate a blast wave traveling in a stellar wind environment that encounters a sudden change in density, followed by a homogeneous medium, and compute the observed radiation using a synchrotron model. We show that flares are not observable for an encounter with a sudden density increase, such as a wind termination shock, nor for an encounter with a sudden density decrease. Furthermore, by extending our analysis to two dimensions, we are able to resolve the spreading, collimation, and edge effects of the blast wave as it encounters the change in circumburst medium. In all cases considered in this paper, we find that a flare will not be observed for any of the density changes studied.

  15. ocean waves

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

    waves - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear Energy Nuclear

  16. Online Travel Reservations through "Concur Travel" | The Ames Laboratory

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

    Online Learning Center Online Learning Center Online Learning Center Whether you're looking to discover new learning opportunities, better manage your career, request external training or connect your employees with the learning they need, OLC provides new features and services to help. Fulfill your training needs with ease and save money on travel and training costs Explore the enhanced catalog and complete a course at your own pace to stay abreast in the latest technology, science

  17. Integrated coherent matter wave circuits

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ryu, C.; Boshier, M. G.

    2015-09-21

    An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through theirmoreelectric polarizability. Moreover, the source of coherent matter waves is a BoseEinstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry.less

  18. Formation of rarefaction waves in origami-based metamaterials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yasuda, H.; Chong, C.; Charalampidis, E. G.; Kevrekidis, P. G.; Yang, J.

    2016-04-15

    Here, we investigate the nonlinear wave dynamics of origami-based metamaterials composed of Tachi-Miura polyhedron (TMP) unit cells. These cells exhibit strain softening behavior under compression, which can be tuned by modifying their geometrical configurations or initial folded conditions. We assemble these TMP cells into a cluster of origami-based metamaterials, and we theoretically model and numerically analyze their wave transmission mechanism under external impact. Numerical simulations show that origami-based metamaterials can provide a prototypical platform for the formation of nonlinear coherent structures in the form of rarefaction waves, which feature a tensile wavefront upon the application of compression to the system.more » We also demonstrate the existence of numerically exact traveling rarefaction waves in an effective lumped-mass model. Origami-based metamaterials can be highly useful for mitigating shock waves, potentially enabling a wide variety of engineering applications.« less

  19. Deflagration Wave Profiles

    SciTech Connect (OSTI)

    Menikoff, Ralph

    2012-04-03

    Shock initiation in a plastic-bonded explosives (PBX) is due to hot spots. Current reactive burn models are based, at least heuristically, on the ignition and growth concept. The ignition phase occurs when a small localized region of high temperature (or hot spot) burns on a fast time scale. This is followed by a growth phase in which a reactive front spreads out from the hot spot. Propagating reactive fronts are deflagration waves. A key question is the deflagration speed in a PBX compressed and heated by a shock wave that generated the hot spot. Here, the ODEs for a steady deflagration wave profile in a compressible fluid are derived, along with the needed thermodynamic quantities of realistic equations of state corresponding to the reactants and products of a PBX. The properties of the wave profile equations are analyzed and an algorithm is derived for computing the deflagration speed. As an illustrative example, the algorithm is applied to compute the deflagration speed in shock compressed PBX 9501 as a function of shock pressure. The calculated deflagration speed, even at the CJ pressure, is low compared to the detonation speed. The implication of this are briefly discussed.

  20. The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates

    SciTech Connect (OSTI)

    Wardaya, P. D. Noh, K. A. B. M. Yusoff, W. I. B. W.; Ridha, S.; Nurhandoko, B. E. B.

    2014-09-25

    This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic wave

  1. Secretary Chu To Travel to China and Japan | Department of Energy

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

    To Travel to China and Japan Secretary Chu To Travel to China and Japan November 5, 2010 - 12:00am Addthis Washington, D.C. -U.S. Energy Secretary Steven Chu will travel to China ...

  2. Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

    SciTech Connect (OSTI)

    Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

    2012-01-10

    In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Gttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

  3. Urban structure and its influence on vehicle travel reduction strategies

    SciTech Connect (OSTI)

    Southworth, F.; Jones, D.W.; Harrison, G.

    1996-04-01

    This paper examines what is known about the relationship between urban spatial structure (i.e. the arrangement of residential, industrial, commercial, recreational and municipal buildings and land lots) and urban travel. The first section provides an overview of the empirical evidence for relationships between urban spatial structure and travel in the United States. Section two focuses on the barriers to and opportunities for reducing the use of automobiles and light trucks in urban areas. The final section offers a policy-point-of-impact perspective on the sort of instruments governments have at their disposal for reducing vehicular travel.

  4. Which Road to Travel? | Y-12 National Security Complex

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

    Which Road to Travel? Which Road to Travel? Posted: July 16, 2013 - 6:06pm There's no question which road (crosswalk) to travel when you park in the North Portal parking lot. Thanks to the recent restriping of the parking lot, the crosswalk and parking spaces are clearly marked. Earlier this year, the Employee-Driven Safety Campaign was created as a way to easily submit safety issues as we continue pursuing Safety for Life and our Voluntary Protection Program focus. Y-12 is a large site, so it

  5. Evolution of rogue waves in dusty plasmas

    SciTech Connect (OSTI)

    Tolba, R. E. El-Bedwehy, N. A.; Moslem, W. M.; El-Labany, S. K.

    2015-04-15

    The evolution of rogue waves associated with the dynamics of positively charged dust grains that interact with streaming electrons and ions is investigated. Using a perturbation method, the basic set of fluid equations is reduced to a nonlinear Schrdinger equation (NLSE). The rational solution of the NLSE is presented, which proposed as an effective tool for studying the rogue waves in Jupiter. It is found that the existence region of rogue waves depends on the dust-acoustic speed and the streaming densities of the ions and electrons. Furthermore, the supersonic rogue waves are much taller than the subsonic rogue waves by ?25 times.

  6. Plane wave method for elastic wave scattering by a heterogeneous...

    Office of Scientific and Technical Information (OSTI)

    Plane wave method for elastic wave scattering by a heterogeneous fracture Citation Details In-Document Search Title: Plane wave method for elastic wave scattering by a ...

  7. Fiber optic sensor employing successively destroyed coupled points or reflectors for detecting shock wave speed and damage location

    DOE Patents [OSTI]

    Weiss, Jonathan D.

    1995-01-01

    A shock velocity and damage location sensor providing a means of measuring shock speed and damage location. The sensor consists of a long series of time-of-arrival "points" constructed with fiber optics. The fiber optic sensor apparatus measures shock velocity as the fiber sensor is progressively crushed as a shock wave proceeds in a direction along the fiber. The light received by a receiving means changes as time-of-arrival points are destroyed as the sensor is disturbed by the shock. The sensor may comprise a transmitting fiber bent into a series of loops and fused to a receiving fiber at various places, time-of-arrival points, along the receiving fibers length. At the "points" of contact, where a portion of the light leaves the transmitting fiber and enters the receiving fiber, the loops would be required to allow the light to travel backwards through the receiving fiber toward a receiving means. The sensor may also comprise a single optical fiber wherein the time-of-arrival points are comprised of reflection planes distributed along the fibers length. In this configuration, as the shock front proceeds along the fiber it destroys one reflector after another. The output received by a receiving means from this sensor may be a series of downward steps produced as the shock wave destroys one time-of-arrival point after another, or a nonsequential pattern of steps in the event time-of-arrival points are destroyed at any point along the sensor.

  8. Fiber optic sensor employing successively destroyed coupled points or reflectors for detecting shock wave speed and damage location

    DOE Patents [OSTI]

    Weiss, J.D.

    1995-08-29

    A shock velocity and damage location sensor providing a means of measuring shock speed and damage location is disclosed. The sensor consists of a long series of time-of-arrival ``points`` constructed with fiber optics. The fiber optic sensor apparatus measures shock velocity as the fiber sensor is progressively crushed as a shock wave proceeds in a direction along the fiber. The light received by a receiving means changes as time-of-arrival points are destroyed as the sensor is disturbed by the shock. The sensor may comprise a transmitting fiber bent into a series of loops and fused to a receiving fiber at various places, time-of-arrival points, along the receiving fibers length. At the ``points`` of contact, where a portion of the light leaves the transmitting fiber and enters the receiving fiber, the loops would be required to allow the light to travel backwards through the receiving fiber toward a receiving means. The sensor may also comprise a single optical fiber wherein the time-of-arrival points are comprised of reflection planes distributed along the fibers length. In this configuration, as the shock front proceeds along the fiber it destroys one reflector after another. The output received by a receiving means from this sensor may be a series of downward steps produced as the shock wave destroys one time-of-arrival point after another, or a nonsequential pattern of steps in the event time-of-arrival points are destroyed at any point along the sensor. 6 figs.

  9. ORISE: CDC Travelers' Health Team Receives Innovation Award for...

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

    CDC Travelers' Health Team Receives Innovation Award for Website Redesign ORISE serves as lead redesign contractor on award-winning website redesign for the CDC How ORISE is Making...

  10. Secretary Chu will Travel to China to Highlight Clean Energy...

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

    WASHINGTON - U.S. Energy Secretary Steven Chu will travel to China from May 24th to 28th to highlight the benefit of U.S.-China partnerships and cooperation in the clean energy ...

  11. U.S. Department of Energy Travel Manual

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2006-02-17

    The Manual supplements information in the Federal Travel Regulation (FTR) by providing further clarification and establishing Department of Energy (DOE) policy on matters that the FTR left to Agency discretion. Supersedes DOE M 552.1-1.

  12. Deputy Secretary Poneman to Travel to Russia | Department of...

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

    Washington, D.C. - On Monday, December 6, U.S. Deputy Secretary of Energy Daniel Poneman will travel to Russia as part of the ongoing cooperation between the two countries on ...

  13. U.S. Department of Energy Travel Manual

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2002-09-04

    To supplement information contained in the Federal Travel Regulation (FTR) by providing further clarification and establishing Department of Energy (DOE) policy on matters that the FTR left to Agency discretion. Canceled by DOE M 552.1-1A.

  14. The Department of Energy's Management of Foreign Travel, IG-0872

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

    The Department of Energy's Management of Foreign Travel DOE/IG-0872 October 2012 U.S. Department of Energy Office of Inspector General Office of Audits and Inspections Department of Energy Washington, DC 20585 October 16, 2012 MEMORANDUM FOR THE SECRETARY FROM: Gregory H. Friedman Inspector General SUBJECT: INFORMATION: Management Alert: "The Department of Energy's Management of Foreign Travel" INTRODUCTION The Department of Energy and its workforce of 116,000 Federal and contractor

  15. NNSA Deputy Administrator Creedon Travels to China | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) Deputy Administrator Creedon Travels to China Monday, April 4, 2016 - 3:46pm Members of the U.S. delegation, led by Secretary of Energy Ernest Moniz, were met by Chinese Vice Premier Ma Kai at the Center of Excellence on Nuclear Security in Beijing. In March, National Nuclear Security Administration (NNSA) Principal Deputy Administrator Madelyn Creedon traveled to China to participate in activities related to NNSA's cooperative engagement with various Chinese

  16. NNSA deputy administrator travels to Ukraine | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) administrator travels to Ukraine Thursday, April 14, 2016 - 10:02am From left, NNSA Director of Strategic Planning/Integration Andy Hood, STCU Executive Director Curtis Bjelajac, NNSA Deputy Administrator Anne Harrington, and NNSA Assistant Deputy Administrator Pete Hanlon. Earlier this month, Deputy Administrator for Defense Nuclear Nonproliferation Anne Harrington traveled to Ukraine to celebrate the 20th anniversary of the Science and Technology Center in Ukraine

  17. MONDAY: Secretary Chu Travels to New Jersey and Philadelphia | Department

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

    of Energy MONDAY: Secretary Chu Travels to New Jersey and Philadelphia MONDAY: Secretary Chu Travels to New Jersey and Philadelphia September 24, 2010 - 12:00am Addthis WASHINGTON - On Monday, September 27, 2010, U.S. Energy Secretary Steven Chu and Representative Rush Holt will tour Applied Photovoltaics. With help from a Recovery Act-funded $1.1 million clean energy manufacturing tax credit, Applied Photovoltaics will manufacture solar energy modules for use in building-integrated

  18. Time Structure of the LANSCE Beam

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

    The proton beam is delivered to Target-1 after passing through the proton storage ring (PSR). The time it takes an 800 MeV proton to travel one circuit of the PSR is 360 ns. The...

  19. Method and apparatus for actively controlling a micro-scale flexural plate wave device

    DOE Patents [OSTI]

    Dohner, Jeffrey L.

    2001-01-01

    An actively controlled flexural plate wave device provides a micro-scale pump. A method of actively controlling a flexural plate wave device produces traveling waves in the device by coordinating the interaction of a magnetic field with actively controlled currents. An actively-controlled flexural plate wave device can be placed in a fluid channel and adapted for use as a micro-scale fluid pump to cool or drive micro-scale systems, for example, micro-chips, micro-electrical-mechanical devices, micro-fluid circuits, or micro-scale chemical analysis devices.

  20. Large neighborhood search for the double traveling salesman problem with multiple stacks

    SciTech Connect (OSTI)

    Bent, Russell W; Van Hentenryck, Pascal

    2009-01-01

    This paper considers a complex real-life short-haul/long haul pickup and delivery application. The problem can be modeled as double traveling salesman problem (TSP) in which the pickups and the deliveries happen in the first and second TSPs respectively. Moreover, the application features multiple stacks in which the items must be stored and the pickups and deliveries must take place in reserve (LIFO) order for each stack. The goal is to minimize the total travel time satisfying these constraints. This paper presents a large neighborhood search (LNS) algorithm which improves the best-known results on 65% of the available instances and is always within 2% of the best-known solutions.

  1. Wave transmission over submerged breakwaters

    SciTech Connect (OSTI)

    Kobayashi, N.; Wurjanto, A. )

    1989-09-01

    Monochromatic wave reflection and transmission over a submerged impermeable breakwater is predicted numerically by slightly modifying the numerical model developed previously for predicting wave reflection and run-up on rough or smooth impermeable slopes. The slight modification is related to the landward boundary condition required for the transmitted wave propagating landward. In addition to the conservation equations of mass and momentum used to compute the flow field, an equation of energy is derived to estimate the rate of energy dissipation due to wave breaking. The computed reflection and transmission coefficients are shown to be in agreement with available small-scale test data. The numerical model also predicts the spatial variation of the energy dissipation, the mean water level difference, and the time-averaged volume flux per unit width, although available measurements are not sufficient for evaluating the capabilities and limitations of the numerical model for predicting these quantities.

  2. Shear wave transducer for boreholes

    DOE Patents [OSTI]

    Mao, N.H.

    1984-08-23

    A technique and apparatus is provided for estimating in situ stresses by measuring stress-induced velocity anisotropy around a borehole. Two sets each of radially and tangentially polarized transducers are placed inside the hole with displacement directions either parallel or perpendicular to the principal stress directions. With this configuration, relative travel times are measured by both a pulsed phase-locked loop technique and a cross correlation of digitized waveforms. The biaxial velocity data are used to back-calculate the applied stress.

  3. Transition probability from matter-wave soliton to chaos

    SciTech Connect (OSTI)

    Zhu Qianquan; Hai Wenhua; Rong Shiguang

    2009-07-15

    For a Bose-Einstein condensate loaded into a weak traveling optical superlattice, it is demonstrated that under a stochastic initial set and in a given parameter region, the solitonic chaos appears with a certain probability. Effects of the lattice depths and wave vectors on the chaos probability are investigated analytically and numerically and different chaotic regions associated with different chaos probabilities are found. The results suggest a method for weakening or strengthening chaos by modulating the moving superlattice.

  4. Wave Energy Scotland

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

    ... Industry outreach: DOE and Wave Energy Scotland co-sponsored WEC technology workshop News, Partnership, Renewable Energy, Water Power, Workshops Industry outreach: DOE and Wave ...

  5. Gravitational waves found, black-hole models led the way

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

    Gravitational waves found, black-hole models led the way Gravitational waves found, black-hole models led the way Gravitational waves were predicted by Einstein's theory of general relativity in 1916, and now, almost exactly 100 years later, the faint ripples across space-time have been found. February 11, 2016 A simulation of two merging black holes, creating gravitational waves. Photo courtesy of LIGO. A simulation of two merging black holes, creating gravitational waves. Photo courtesy of

  6. Stochastic features of multipactor in coaxial waveguides for travelling and standing waves

    SciTech Connect (OSTI)

    Romanov, Gennady; /Fermilab

    2011-02-01

    CST Particle Studio combines electromagnetic field simulation, multi-particle tracking, adequate post-processing and advanced probabilistic emission model, which is the most important new capability in multipactor simulation. The emission model includes in simulation the stochastic properties of emission and adds primary electron elastic and inelastic reflection from the surfaces. The simulation of multipactor in coaxial waveguides have been performed to study the effects of the innovations on the multipactor threshold and the range over which multipactor can occur. The results compared with available previous experiments and simulations as well as the technique of MP simulation with CST PS are presented and discussed.

  7. Orthogonally interdigitated shielded serpentine travelling wave cathode ray tube deflection structure

    DOE Patents [OSTI]

    Hagen, E.C.; Hudson, C.L.

    1995-07-25

    A new deflection structure which deflects a beam of charged particles, such as an electron beam, includes a serpentine set for transmitting a deflection field, and a shielding frame for housing the serpentine set. The serpentine set includes a vertical serpentine deflection element and a horizontal serpentine deflection element. These deflection elements are identical, and are interdigitatedly and orthogonally disposed relative to each other, for forming a central transmission passage, through which the electron beam passes, and is deflected by the deflection field, so as to minimize drift space signal distortion. The shielding frame includes a plurality of ground blocks, and forms an internal serpentine trough within these ground blocks, for housing the serpentine set. The deflection structure further includes a plurality of feedthrough connectors which are inserted through the shielding frame, and which are electrically connected to the serpentine set. 10 figs.

  8. Orthogonally interdigitated shielded serpentine travelling wave cathode ray tube deflection structure

    DOE Patents [OSTI]

    Hagen, Edward C.; Hudson, Charles L.

    1995-01-01

    A new deflection structure (12) which deflects a beam of charged particles, uch as an electron beam (15), includes a serpentine set (20) for transmitting a deflection field, and a shielding frame (25) for housing the serpentine set (20). The serpentine set (20) includes a vertical serpentine deflection element (22) and a horizontal serpentine deflection element (24). These deflection elements (22, 24) are identical, and are interdigitatedly and orthogonally disposed relative to each other, for forming a central transmission passage (75), through which the electron beam (15) passes, and is deflected by the deflection field, so as to minimize drift space signal distortion. The shielding frame (25) includes a plurality of ground blocks (26, 28, 30, 32), and forms an internal serpentine trough (77) within these ground blocks, for housing the serpentine set (20). The deflection structure (12) further includes a plurality of feedthrough connectors (35, 37, 35I, 37I), which are inserted through the shielding frame (25), and which are electrically connected to the serpentine set (20).

  9. EERE Success Story—Thurston Regional Planning Council Helps Washingtonians Save on Travel Costs

    Broader source: Energy.gov [DOE]

    Thurston County provides travel information for lower costs, improved safety, and faster response to challenges.

  10. High Resolution Photon Timing with MCP-PMTs: A Comparison of a Commercial Constant Fraction Discriminator (CFD) with the ASIC-based Waveform Digitizers TARGET and WaveCatcher

    SciTech Connect (OSTI)

    Breton, D.; Delagnes, E.; Maalmi, J.; Nishimura, K.; Ruckman, L.L.; Varner, G.; Va'vra, J.

    2011-07-14

    There is a considerable interest to develop new time-of-flight detectors using, for example, micro-channel-plate photodetectors (MCP-PMTs). The question we pose in this paper is if new waveform digitizer ASICs, such as the WaveCatcher and TARGET, operating with a sampling rate of 2-3 GSa/s can compete with 1GHz BW CFD/TDC/ADC electronics. We have performed a series of measurements with these waveform digitizers coupled to MCP-PMTs operating at low gain and with a signal equivalent to {approx}40 photoelectrons. The tests were done with a laser diode on detectors operating under the same condition used previously in SLAC and Fermilab beam tests. Our test results indicate that one can achieve similar resolution with both methods. Although the commercial CFD-based electronics does exist and performs very well, it is difficult to implement on a very large scale, and therefore the custom electronics is needed. In addition, the analog delay line requirement makes it very difficult to incorporate CFD discriminators in ASIC designs.