National Library of Energy BETA

Sample records for 3-dimensional converted shear

  1. 3-dimensional imaging at nanometer resolutions

    DOE Patents [OSTI]

    Werner, James H. (Los Alamos, NM); Goodwin, Peter M. (Los Alamos, NM); Shreve, Andrew P. (Santa Fe, NM)

    2010-03-09

    An apparatus and method for enabling precise, 3-dimensional, photoactivation localization microscopy (PALM) using selective, two-photon activation of fluorophores in a single z-slice of a sample in cooperation with time-gated imaging for reducing the background radiation from other image planes to levels suitable for single-molecule detection and spatial location, are described.

  2. Beam converter

    DOE Patents [OSTI]

    Poulsen, Peter

    2003-05-06

    A converter and method for converting electron energy to irradiative energy comprising foam and/or foil. Foam and foil optionally comprise a high-Z material, such as, but not limited to, tantalum.

  3. Thermionic converter

    DOE Patents [OSTI]

    Fitzpatrick, G.O.

    1987-05-19

    A thermionic converter is set forth which includes an envelope having an electron collector structure attached adjacent to a wall. An electron emitter structure is positioned adjacent the collector structure and spaced apart from opposite wall. The emitter and collector structures are in a common chamber. The emitter structure is heated substantially only by thermal radiation. Very small interelectrode gaps can be maintained utilizing the thermionic converter whereby increased efficiency results. 10 figs.

  4. A methodology for generation of a 3-dimensional facility model 

    E-Print Network [OSTI]

    Chawla, Ravi

    2001-01-01

    The thesis is written in the area of 3-Dimensional (3-D) representation of the facility layout using Virtual Reality (VR) environment. The facility layout problem has been solved in literature by several mathematical programming and heuristic...

  5. Light field applications to 3-dimensional surface imaging

    E-Print Network [OSTI]

    Hong, Wenxian

    2009-01-01

    The structure of light around a scene may be contained in a 4-dimensional array known as a light field. This thesis describes methods for acquiring and manipulating light fields for applications in 3-dimensional imaging. ...

  6. The Kurtosis of the Cosmic Shear Field

    E-Print Network [OSTI]

    Masahiro Takada; Bhuvnesh Jain

    2002-08-14

    We study the fourth-order moment of the cosmic shear field using the dark matter halo approach to describe the nonlinear gravitational evolution of structure in the universe. Since the third-order moment of the shear field vanishes because of symmetry, non-Gaussian signatures in its one-point statistics emerge at the fourth-order level. We argue that the shear kurtosis parameter S_4 = /^3 may be more directly applicable to realistic data than the well-studied higher-order statistics of the convergence field, since obtaining the convergence requires a non-local reconstruction from the measured shear field. We compare our halo model predictions for the variance, skewness and kurtosis of lensing fields with ray-tracing simulations of cold dark matter models and find good agreement. The shear kurtosis calculation is made tractable by developing approximations for fast and accurate evaluations of the 8-dimensional integrals needed to obtain the kurtosis. We show that on small scales it is dominated by correlations within halos more massive than 10^14 solar masses. The shear kurtosis is sensitive to the mass density parameter of the universe, Omega, and has relatively weak dependences on other parameters. The approximations we develop for the third- and fourth-order moments allow for accurate halo model predictions for the 3-dimensional mass distribution as well. We demonstrate their accuracy in the small scale regime, below 2 Mpc, where analytical approaches used in the literature so far cease to be accurate.

  7. Power Converters for Accelerators

    E-Print Network [OSTI]

    Visintini, R

    2015-01-01

    Particle accelerators use a great variety of power converters for energizing their sub-systems; while the total number of power converters usually depends on the size of the accelerator or combination of accelerators (including the experimental setup), the characteristics of power converters depend on their loads and on the particle physics requirements: this paper aims to provide an overview of the magnet power converters in use in several facilities worldwide.

  8. Switching Power Converter A/D Converters

    E-Print Network [OSTI]

    to make intelligent decisions on load and system management prior to system faults. With the increased use of the converter [1]. Traditionally, system monitoring and control is performed by a central power management

  9. Heat pulse propagation in chaotic 3-dimensional magnetic fields

    E-Print Network [OSTI]

    D. del-Castillo-Negrete; D. Blazevski

    2014-09-10

    Heat pulse propagation in $3$-D chaotic magnetic fields is studied by solving the parallel heat transport equation using a Lagrangian-Green's function (LG) method. The LG method provides an efficient and accurate technique that circumvents limitations of finite elements and finite difference methods. The main two problems addressed are: (i) The dependence of the radial transport on the magnetic field stochasticity (controlled by the amplitude of the perturbation, $\\epsilon$); and (ii) The role of reversed shear configurations on pulse propagation. In all the cases considered there are no magnetic flux surfaces. However, radial transport is observed to depend strongly on $\\epsilon$ due to the presence of high-order magnetic islands and Cantori that act as quasi-transport barriers that preclude the radial penetration of heat pulses within physically relevant time scale. The dependence of the magnetic field connection length, $\\ell_B$, on $\\epsilon$ is studied in detail. The decay rate of the temperature maximum, $\\langle T \\rangle_{max}(t)$, the time delay of the temperature response as function of the radius, $\\tau$, and the radial heat flux $\\langle {{\\bf q}\\cdot {\\hat e}_\\psi} \\rangle$, are also studied as functions of the magnetic field stochasticity and $\\ell_B$. In all cases, the scaling of $\\langle T \\rangle_{max}$ with $t$ transitions from sub-diffusive, $\\langle T \\rangle_{max} \\sim t^{-1/4}$, at short times ($\\chi_\\parallel t 10^5$). A strong dependence on $\\epsilon$ is also observed on $\\tau$ and $\\langle {{\\bf q}\\cdot {\\hat e}_\\psi} \\rangle$. The radial propagation of pulses in fully chaotic fields considerably slows down in the shear reversal region and, as a result, $\\tau$, in reversed shear configurations is an order of magnitude longer than the one in monotonic $q$-profiles.

  10. Interleaved power converter

    DOE Patents [OSTI]

    Zhu, Lizhi (Canton, MI)

    2007-11-13

    A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.

  11. Universal thermochemical energy converter

    DOE Patents [OSTI]

    Labinov, Solomon Davidovich (Oak Ridge, TN); Sand, James R. (Oak Ridge, TN); Conklin, James C. (Knoxville, TN); VanCoevering, James (Oak Ridge, TN); Courville, George E. (Oak Ridge, TN)

    2001-01-01

    Disclosed are methods and apparatus for a thermochemical closed cycle employing a polyatomic, chemically active working fluid for converting heat energy into useful work.

  12. 3-dimensional imaging system using crystal diffraction lenses

    DOE Patents [OSTI]

    Smither, Robert K. (Hinsdale, IL)

    1999-01-01

    A device for imaging a plurality of sources of x-ray and gamma-ray radiation is provided. Diffracting crystals are used for focussing the radiation and directing the radiation to a detector which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for a method for imaging x-ray and gamma radiation by supplying a plurality of sources of radiation; focussing the radiation onto a detector; analyzing the focused radiation to collect data as to the type and location of the radiation; and producing an image using the data.

  13. 3-dimensional imaging system using crystal diffraction lenses

    DOE Patents [OSTI]

    Smither, R.K.

    1999-02-09

    A device for imaging a plurality of sources of x-ray and gamma-ray radiation is provided. Diffracting crystals are used for focusing the radiation and directing the radiation to a detector which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for a method for imaging x-ray and gamma radiation by supplying a plurality of sources of radiation; focusing the radiation onto a detector; analyzing the focused radiation to collect data as to the type and location of the radiation; and producing an image using the data. 18 figs.

  14. 3-DIMENSIONAL GEOMECHANICAL MODELING OF A TIGHT GAS RESERVOIR, RULISON FIELD, PICEANCE BASIN, COLORADO

    E-Print Network [OSTI]

    3-DIMENSIONAL GEOMECHANICAL MODELING OF A TIGHT GAS RESERVOIR, RULISON FIELD, PICEANCE BASIN, COLORADO by Kurtis R. Wikel #12;ii #12;iii ABSTRACT An integrated 3-dimensional geomechanical model have used the predictive geomechanical model to compare production and effective stress change

  15. Microminiature thermionic converters

    DOE Patents [OSTI]

    King, Donald B. (Albuquerque, NM); Sadwick, Laurence P. (Salt Lake City, UT); Wernsman, Bernard R. (Clairton, PA)

    2001-09-25

    Microminiature thermionic converts (MTCs) having high energy-conversion efficiencies and variable operating temperatures. Methods of manufacturing those converters using semiconductor integrated circuit fabrication and micromachine manufacturing techniques are also disclosed. The MTCs of the invention incorporate cathode to anode spacing of about 1 micron or less and use cathode and anode materials having work functions ranging from about 1 eV to about 3 eV. Existing prior art thermionic converter technology has energy conversion efficiencies ranging from 5-15%. The MTCs of the present invention have maximum efficiencies of just under 30%, and thousands of the devices can be fabricated at modest costs.

  16. Voltage Converter TYPICAL APPLICATION

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    1 LTC660 100mA CMOS Voltage Converter TYPICAL APPLICATION U s Simple Conversion of 5V to ­5V Supply s Output Drive: 100mA s ROUT: 6.5 (0.65V Loss at 100mA) s BOOST Pin (Pin 1) for Higher Switching Frequency-capacitor voltage converter. It performs supply voltage conversion from positive to negative from an input range

  17. Reduced shear power spectrum

    SciTech Connect (OSTI)

    Dodelson, Scott; /Fermilab /Chicago U., Astron. Astrophys. Ctr. /Northwestern U.; Shapiro, Charles; /Chicago U. /KICP, Chicago; White, Martin J.; /UC, Berkeley, Astron.

    2005-08-01

    Measurements of ellipticities of background galaxies are sensitive to the reduced shear, the cosmic shear divided by (1-{kappa}) where {kappa} is the projected density field. They compute the difference between shear and reduced shear both analytically and with simulations. The difference becomes more important an smaller scales, and will impact cosmological parameter estimation from upcoming experiments. A simple recipe is presented to carry out the required correction.

  18. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, James M. (Livermore, CA); Leighton, James F. (Livermore, CA)

    1990-01-01

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.

  19. Vector generator scan converter

    DOE Patents [OSTI]

    Moore, J.M.; Leighton, J.F.

    1988-02-05

    High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.

  20. Liquid metal thermal electric converter

    DOE Patents [OSTI]

    Abbin, Joseph P. (Albuquerque, NM); Andraka, Charles E. (Albuquerque, NM); Lukens, Laurance L. (Albuquerque, NM); Moreno, James B. (Albuquerque, NM)

    1989-01-01

    A liquid metal thermal electric converter which converts heat energy to electrical energy. The design of the liquid metal thermal electric converter incorporates a unique configuration which directs the metal fluid pressure to the outside of the tube which results in the structural loads in the tube to be compressive. A liquid metal thermal electric converter refluxing boiler with series connection of tubes and a multiple cell liquid metal thermal electric converter are also provided.

  1. Definition of Power Converters

    E-Print Network [OSTI]

    Bordry, F

    2015-01-01

    The paper is intended to introduce power conversion principles and to define common terms in the domain. The concept s of sources and switches are defined and classified. From the basic laws of source interconnections, a generic method of power converter synthesis is presented. Some examples illustrate this systematic method. Finally, the commutation cell and soft commuta tion are introduced and discussedd.

  2. Shear wall ultimate drift limits

    SciTech Connect (OSTI)

    Duffey, T.A.; Goldman, A.; Farrar, C.R.

    1994-04-01

    Drift limits for reinforced-concrete shear walls are investigated by reviewing the open literature for appropriate experimental data. Drift values at ultimate are determined for walls with aspect ratios ranging up to a maximum of 3.53 and undergoing different types of lateral loading (cyclic static, monotonic static, and dynamic). Based on the geometry of actual nuclear power plant structures exclusive of containments and concerns regarding their response during seismic (i.e.,cyclic) loading, data are obtained from pertinent references for which the wall aspect ratio is less than or equal to approximately 1, and for which testing is cyclic in nature (typically displacement controlled). In particular, lateral deflections at ultimate load, and at points in the softening region beyond ultimate for which the load has dropped to 90, 80, 70, 60, and 50 percent of its ultimate value, are obtained and converted to drift information. The statistical nature of the data is also investigated. These data are shown to be lognormally distributed, and an analysis of variance is performed. The use of statistics to estimate Probability of Failure for a shear wall structure is illustrated.

  3. The Geography of European Convertible Bonds: Why Firms Issue Convertibles?

    E-Print Network [OSTI]

    Saskatchewan, University of

    1 The Geography of European Convertible Bonds: Why Firms Issue Convertibles? Franck Bancel Usha R at the geography of CB issuance. The size and development of the CB market varies widely across countries and over

  4. Reprint from the Bulletin of the Belgian Mathematical Society Simon Stevin Lagrangian submanifolds in 3-dimensional

    E-Print Network [OSTI]

    Li, Haizhong

    of Project Euclid (Cornell University Library), an aggregation of electronic journals. It is available online classification of the Lagrangian submanifolds in 3-dimensional complex space forms with isotropic cubic tensor. 1 Mathematics Subject Classification : Primary 53C20; Secondary 53C42. Key words and phrases : Lagrangian

  5. Advanced 3-Dimensional CAD Modeling of the Gear Hobbing Process V. Dimitriou 1

    E-Print Network [OSTI]

    Aristomenis, Antoniadis

    Advanced 3-Dimensional CAD Modeling of the Gear Hobbing Process V. Dimitriou 1 , A. Antoniadis 1* 1 to the realistic and accurate simulation of the gear hobbing process, an effec- tive and factual approximation is directly applied in one gear gap. Each generating position formulates a three dimensional surface path

  6. A Cellular Model for 3-Dimensional Snow Crystallization Faculty of Information & Control Engineering, Shenyang Jianzhu University,

    E-Print Network [OSTI]

    Reiter, Clifford A.

    A Cellular Model for 3-Dimensional Snow Crystallization Chen Ning Faculty of Information & Control Snow crystals are intriguing because they exhibit both symmetry and remarkable diversity. Previous studies have used 2-dimensional models to approximate snow-crystal growth. Here generalizations to three

  7. Computational analysis of shrouded wind turbine configurations using a 3-dimensional RANS solver

    E-Print Network [OSTI]

    Alonso, Juan J.

    October 2014 Available online Keywords: Wind energy Shrouded wind turbines DAWT CFD Transition model a b presently confronting the widespread adoption of wind energy is cost. Improvements in wind turbineComputational analysis of shrouded wind turbine configurations using a 3-dimensional RANS solver

  8. PEMFC ELECTROCHEMISTRY: SIMULATION OF NONEQUILIBRIUM SURFACE CHEMISTRY ON 3-DIMENSIONAL GEOMETRIES

    E-Print Network [OSTI]

    Pitsch, Heinz

    PEMFC ELECTROCHEMISTRY: SIMULATION OF NONEQUILIBRIUM SURFACE CHEMISTRY ON 3-DIMENSIONAL GEOMETRIES in transportation [1]. Carbon-supported platinum catalysts are com- monly used in the catalyst layer of PEMFC due used to describe oxygen reduction on Pt-nanoparticles in PEMFC will be discussed next, followed

  9. ULTRA-HIGH SURFACE AREA SINGLE AND MULTI-WALLED CARBON NANOTUBE 3-DIMENSIONAL HYBRID STRUCTURE

    E-Print Network [OSTI]

    Mellor-Crummey, John

    flexible electronic devices, membranes, sensors, and energy storage devices, the primary reason being surface area 3-dimensional hybrid nanostructure by combining carbon nanotube growth on two templates. This novel hybrid carbon nanostructure demonstrates an enhanced conductive surface area that paves the way

  10. 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 exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.

  11. Bidirectional buck boost converter

    DOE Patents [OSTI]

    Esser, A.A.M.

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero. 20 figs.

  12. Bidirectional buck boost converter

    DOE Patents [OSTI]

    Esser, Albert Andreas Maria (Niskayuna, NY)

    1998-03-31

    A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

  13. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  14. Shear Unzipping of DNA

    E-Print Network [OSTI]

    Buddhapriya Chakrabarti; David R. Nelson

    2009-04-09

    We study theoretically the mechanical failure of a simple model of double stranded DNA under an applied shear. Starting from a more microscopic Hamiltonian that describes a sheared DNA, we arrive at a nonlinear generalization of a ladder model of shear unzipping proposed earlier by deGennes [deGennes P. G. C. R. Acad. Sci., Ser. IV; Phys., Astrophys. 2001, 1505]. Using this model and a combination of analytical and numerical methods, we study the DNA "unzipping" transition when the shearing force exceeds a critical threshold at zero temperature. We also explore the effects of sequence heterogeneity and finite temperature and discuss possible applications to determine the strength of colloidal nanoparticle assemblies functionalized by DNA.

  15. Electromagnetic Compatibility of Power Converters

    E-Print Network [OSTI]

    Charoy, A

    2015-01-01

    This paper describes the main challenges related to power converters in a scientific environment. It proposes some methods of EMC analysis, design, meas urement, and EMC troubleshooting.

  16. Self-powered microthermionic converter

    DOE Patents [OSTI]

    Marshall, Albert C.; King, Donald B.; Zavadil, Kevin R.; Kravitz, Stanley H.; Tigges, Chris P.; Vawter, Gregory A.

    2004-08-10

    A self-powered microthermionic converter having an internal thermal power source integrated into the microthermionic converter. These converters can have high energy-conversion efficiencies over a range of operating temperatures. Microengineering techniques are used to manufacture the converter. The utilization of an internal thermal power source increases potential for mobility and incorporation into small devices. High energy efficiency is obtained by utilization of micron-scale interelectrode gap spacing. Alpha-particle emitting radioisotopes can be used for the internal thermal power source, such as curium and polonium isotopes.

  17. CHIC - Converting Hamburgers Into Cows

    E-Print Network [OSTI]

    Townsend, Joseph A

    components and convert them into SciXML. This is sectioned into text-rich and data-rich streams and stand-off annotation (SAF) is created for each. Embedded domain specific objects can be converted into XML (Chemical Markup Language). The different workflow...

  18. Power Converters for Cycling Machines

    E-Print Network [OSTI]

    Bouteille, J F

    2015-01-01

    Cycling accelerators require power converters that are capable of storing the energy that oscillates between lattice magnets and the converter during the acceleration process. This paper presents the basic requirements for such systems and reviews the various electrical circuits that have been used for a variety of differing applications. The designs currently used for fast-, medium- and slow-cycling accelerators are presented.

  19. Shearing Strength of Concrete

    E-Print Network [OSTI]

    Gallup, R. F.; Russell, F. A.

    1907-01-01

    was to obtain values of shear that might be applied in the design of masonry. BIBLIOGRAPHY. Beu30hanger. In 1878, Herr Bau^changer con­ ducted a series of tests on parte of concrete prisms that had been broken by flexur?. He found concrete two years old... in iron damping frames* The clamping frames 7 and surface plates were made from scrap eastings* The drawings will show without further description* the arrangement of molds and ft*«BM« fnlf design was found fairly satisfactory* the shears ware made...

  20. One-way wave-equation migration of compressional and converted waves in a VTI medium

    E-Print Network [OSTI]

    Ursin, Bjørn

    One-way wave-equation migration of compressional and converted waves in a VTI medium Ørjan Pedersen- sure and shear-wave reflections, one can increase the amount of information obtained about the subsur- face than by recording pressure waves alone. Geo- logic structures which are not visible by using con

  1. MT3D: a 3 dimensional magnetotelluric modeling program (user's guide and documentation for Rev. 1)

    SciTech Connect (OSTI)

    Nutter, C.; Wannamaker, P.E.

    1980-11-01

    MT3D.REV1 is a non-interactive computer program written in FORTRAN to do 3-dimensional magnetotelluric modeling. A 3-D volume integral equation has been adapted to simulate the MT response of a 3D body in the earth. An integro-difference scheme has been incorporated to increase the accuracy. This is a user's guide for MT3D.REV1 on the University of Utah Research Institute's (UURI) PRIME 400 computer operating under PRIMOS IV, Rev. 17.

  2. Switched-Mode Power Converter Programmable

    E-Print Network [OSTI]

    Switched-Mode Power Converter Programmable compensator Identification & design Vref DPWM vout digital controller design for switching power converters. Starting from an experimentally identified Digital Controller Design for Switching Converters Abstract--This paper presents an approach to automated

  3. Shear-Induced Chaos

    E-Print Network [OSTI]

    Kevin K. Lin; Lai-Sang Young

    2007-05-23

    Guided by a geometric understanding developed in earlier works of Wang and Young, we carry out some numerical studies of shear-induced chaos. The settings considered include periodic kicking of limit cycles, random kicks at Poisson times, and continuous-time driving by white noise. The forcing of a quasi-periodic model describing two coupled oscillators is also investigated. In all cases, positive Lyapunov exponents are found in suitable parameter ranges when the forcing is suitably directed.

  4. Converting Biomass to High-Value Feedstocks

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

    Converting Biomass to High-Value Feedstocks Advanced feedstocks play an important role in economically and efficiently converting biomass into bioenergy products. Advanced...

  5. Towards a mathematical definition of Coulomb branches of $3$-dimensional $\\mathcal N=4$ gauge theories, I

    E-Print Network [OSTI]

    Nakajima, Hiraku

    2015-01-01

    Consider the $3$-dimensional $\\mathcal N=4$ supersymmetric gauge theory associated with a compact Lie group $G$ and its quaternionic representation $\\mathbf M$. Physicists study its Coulomb branch, which is a noncompact hyper-K\\"ahler manifold, such as instanton moduli spaces on $\\mathbb R^4$, $SU(2)$-monopole moduli spaces on $\\mathbb R^3$, etc. In this paper and its sequel, we propose a mathematical definition of the coordinate ring of the Coulomb branch, using the vanishing cycle cohomology group of a certain moduli space for a gauged $\\sigma$-model on the $2$-sphere associated with $(G,\\mathbf M)$. In this first part, we check that the cohomology group has the correct graded dimensions expected from the monopole formula proposed by Cremonesi, Hanany and Zaffaroni arXiv:1309.2657. A ring structure (on the cohomology of a modified moduli space) will be introduced in the sequel of this paper.

  6. Charge-pump voltage converter

    DOE Patents [OSTI]

    Brainard, John P. (Albuquerque, NM); Christenson, Todd R. (Albuquerque, NM)

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  7. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A. (Livermore, CA)

    2011-03-15

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

  8. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler,; Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2010-10-26

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  9. Portable convertible blast effects shield

    DOE Patents [OSTI]

    Pastrnak, John W. (Livermore, CA); Hollaway, Rocky (Modesto, CA); Henning, Carl D. (Livermore, CA); Deteresa, Steve (Livermore, CA); Grundler, Walter (Hayward, CA); Hagler, Lisle B. (Berkeley, CA); Kokko, Edwin (Dublin, CA); Switzer, Vernon A (Livermore, CA)

    2007-05-22

    A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

  10. Shear wall ultimate drift limits for PRA applications

    SciTech Connect (OSTI)

    Duffey, T.A. [New Mexico Highlands Univ., Las Vegas, NM (United States); Farrar, C.R.; Goldman, A. [Los Alamos National Lab., NM (United States)

    1995-03-01

    Drift limits for reinforced concrete shear walls are investigated by reviewing the technical literature for appropriate experimental data. Based on the geometry of actual nuclear power plant structures (exclusive of containments) and concerns regarding their response during seismic loading, data are obtained from pertinent references where the wall aspect ratio is less than or equal to approximately 1, and for which the loading is cyclic. Lateral deflections at ultimate load, and at points in the softening region beyond ultimate, are obtained and converted to drift information. The statistical nature of the data is also investigated. These data are shown to be lognormally distributed, and an analysis of variance is performed. The use of these statistics to estimate Probability of Failure for a shear wall structure is illustrated.

  11. SU-E-T-104: Development of 3 Dimensional Dosimetry System for Gamma Knife

    SciTech Connect (OSTI)

    Yoon, K; Kwak, J; Cho, B; Lee, D; Ahn, S

    2014-06-01

    Purpose: The aim of this study was to develop a new 3 dimensional dosimetry system to verify the dosimetric accuracy of Leksell Gamma Knife-Perfexion™ (LGK) (Elekta, Norcross, GA). Methods: We designed and manufactured a lightweight dosimetry instrument to be equipped with the head frame to LGK. It consists of a head phantom, a scintillator, a CCD camera and a step motor. The 10×10 cm2 sheet of Gd2O3;Tb phosphor or Gafchromic EBT3 film was located at the center of the 16 cm diameter hemispherical PMMA, the head phantom. The additional backscatter compensating material of 1 cm thick PMMA plate was placed downstream of the phosphor sheet. The backscatter plate was transparent for scintillation lights to reach the CCD camera with 1200×1200 pixels by 5.2 um pitch. With This equipment, 300 images with 0.2 mm of slice gap were acquired under three collimator setups (4mm, 8mm and 16mm), respectively. The 2D projected doses from 3D distributions were compared with the exposured film dose. Results: As all doses normalized by the maximum dose value in 16 mm setup, the relative differences between the equipment dose and film dose were 0.2% for 4mm collimator and 0.5% for 8mm. The acquisition of 300 images by the equipment took less than 3 minutes. Conclusion: The new equipment was verified to be a good substitute to radiochromic film, with which required more time and resources. Especially, the new methods was considered to provide much convenient and faster solution in the 3D dose acquisition for LGK.

  12. Shear Banding of Complex Fluids

    E-Print Network [OSTI]

    Thibaut Divoux; Marc A. Fardin; Sébastien Manneville; Sandra Lerouge

    2015-03-13

    Even in simple geometries many complex fluids display non-trivial flow fields, with regions where shear is concentrated. The possibility for such shear banding has been known since several decades, but the recent years have seen an upsurge of studies offering an ever more precise understanding of the phenomenon. The development of new techniques to probe the flow on multiple scales and with increasing spatial and temporal resolution has opened the possibility for a synthesis of the many phenomena that could only have been thought of separately before. In this review, we bring together recent research on shear banding in polymeric and on soft glassy materials, and highlight their similarities and disparities.

  13. General Impedance Synthesis Using Simple Switching Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    -frequency storage element and a pair of switches, such as the buck, buck-boost and boost converters, as shown in FigGeneral Impedance Synthesis Using Simple Switching Converters Joe C. P. Liu, Chi K. Tse, Franki N converters is studied in this paper. We begin with showing that any impedance can be synthesized by a circuit

  14. Complex Behavior in Switching Power Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    Complex Behavior in Switching Power Converters CHI K. TSE, SENIOR MEMBER, IEEE, AND MARIO DI--Bifurcation, chaos, dc­dc converters, nonlinear dy- namics, power electronics, switching power converters. I power devices, control methods, circuit design, computer-aided analysis, passive components, packaging

  15. Auxiliary resonant DC tank converter

    DOE Patents [OSTI]

    Peng, Fang Z. (Knoxville, TN)

    2000-01-01

    An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

  16. Enterprise converting buses to biodiesel

    Broader source: Energy.gov [DOE]

    Rental car customers may be able to breathe a little easier during their next trip to the airport. Alamo Rent A Car, Enterprise Rent-A-Car, and National Car Rental, all brands operated by the subsidiaries of Enterprise Holdings, are converting their airport shuttle buses to run on biodiesel fuel. The move is a good one for the environment, and will ultimately reduce the company’s carbon emissions. “We are saving 420,000 gallons of petroleum diesel,”  says Lee Broughton, director of corporate identity and sustainability for Enterprise Holdings.    

  17. Converting Energy to Medical Progress

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentratingPortal ControllingConvection feedbacksConverting

  18. Multiple Shear Key Connections for Precast

    E-Print Network [OSTI]

    for elevator shaft shear wall panelsOne of the main concerns in precast 104 #12;utilize a combination elevator shaft shear wall panels. The tests results were used to develop analytical models to predict the shear Synopsis Seven horizontal connections typi- cally used in precast concrete elevator shaft shear

  19. Sandia Energy - WEC-Sim (Wave Energy Converter SIMulator)

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

    WEC-Sim (Wave Energy Converter SIMulator) Home Stationary Power Energy Conversion Efficiency Water Power WEC-Sim (Wave Energy Converter SIMulator) WEC-Sim (Wave Energy Converter...

  20. Estimation of shear-wave interval attenuation from mode-converted data Bharath Shekar1

    E-Print Network [OSTI]

    Tsvankin, Ilya

    Tsvankin1 ABSTRACT Interval attenuation measurements provide valuable infor- mation for reservoir characterization and lithology discrimi- nation. We extend the attenuation layer-stripping method of Behura of the material (Prasad and Nur, 2003), the pre- sence of aligned fluid-filled fractures (Chapman, 2003; Batzle et

  1. Conducting a 3D Converted Shear Wave Project to Reduce Exploration Risk at

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum Based Fuels|ProgramsLake Paiute Reservation |Department ofWELCOME

  2. Ocean floor mounting of wave energy converters

    DOE Patents [OSTI]

    Siegel, Stefan G

    2015-01-20

    A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

  3. Vacuum-insulated catalytic converter

    DOE Patents [OSTI]

    Benson, David K. (Golden, CO)

    2001-01-01

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  4. Controller for a wave energy converter

    DOE Patents [OSTI]

    Wilson, David G.; Bull, Diana L.; Robinett, III, Rush D.

    2015-09-22

    A wave energy converter (WEC) is described, the WEC including a power take off (PTO) that converts relative motion of bodies of the WEC into electrical energy. A controller controls operation of the PTO, causing the PTO to act as a motor to widen a wave frequency spectrum that is usable to generate electrical energy.

  5. RF digital-to-analog converter

    DOE Patents [OSTI]

    Conway, Patrick H. (Rancho Palos Verdes, CA); Yu, David U. L. (Rancho Palos Verdes, CA)

    1995-01-01

    A digital-to analogue converter for producing an RF output signal proportional to a digital input word of N bits from an RF reference input, N being an integer greater or equal to 2. The converter comprises a plurality of power splitters, power combiners and a plurality of mixers or RF switches connected in a predetermined configuration.

  6. RF digital-to-analog converter

    DOE Patents [OSTI]

    Conway, P.H.; Yu, D.U.L.

    1995-02-28

    A digital-to-analog converter is disclosed for producing an RF output signal proportional to a digital input word of N bits from an RF reference input, N being an integer greater or equal to 2. The converter comprises a plurality of power splitters, power combiners and a plurality of mixers or RF switches connected in a predetermined configuration. 18 figs.

  7. Time interleaved counter analog to digital converters 

    E-Print Network [OSTI]

    Danesh, Seyed Amir Ali

    2011-11-22

    The work explores extending time interleaving in A/D converters, by applying a high-level of parallelism to one of the slowest and simplest types of data-converters, the counter ADC. The motivation for the work is to ...

  8. Switched Mode Four-Quadrant Converters

    E-Print Network [OSTI]

    Thurel, Y

    2015-01-01

    This paper was originally presented at CAS-2004, and was slightly modified for CAS-2014. It presents a review of the key parameters that impact the design choices for a true four-quadrant power converter, in the range 1-10 kW, mainly based on switching mode converter topology. This paper will first describe the state-of-the-art for this power converter family, giving the drawbacks and advantages of different possible solutions. It will also present practical results obtained from the CERN-designed converter. It will finally give some important tips regarding critical phases like test one, when conducting a project dealing with this type of power converter.

  9. Dynamic Electronic Control of Catalytic Converters | Department...

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

    Commonalities between Non-road and On-road Diesel Emissions Diesel Injection Shear-Stress Advanced Nozzle (DISSAN) Microstructural Contol of the Porous Si3N4 Ceramics Consisted...

  10. Refraction of shear zones in granular materials

    E-Print Network [OSTI]

    Tamas Unger

    2007-01-08

    We study strain localization in slow shear flow focusing on layered granular materials. A heretofore unknown effect is presented here. We show that shear zones are refracted at material interfaces in analogy with refraction of light beams in optics. This phenomenon can be obtained as a consequence of a recent variational model of shear zones. The predictions of the model are tested and confirmed by 3D discrete element simulations. We found that shear zones follow Snell's law of light refraction.

  11. Chapter 4587 TROPICAL CYCLOGENESIS IN WIND SHEAR

    E-Print Network [OSTI]

    Nolan, David S.

    , it is shown that small values of wind shear in the range of 1.25 to 5 ms -1 are the most favorable, and very and middle troposphere, and a relatively small value of vertical wind shear, which is the change with heightChapter 4587 TROPICAL CYCLOGENESIS IN WIND SHEAR: CLIMATOLOGICAL RELATIONSHIPS AND PHYSICAL

  12. Controlled shear/tension fixture

    DOE Patents [OSTI]

    Hsueh, Chun-Hway (Knoxville, TN); Liu, Chain-tsuan (Knoxville, TN); George, Easo P. (Knoxville, TN)

    2012-07-24

    A test fixture for simultaneously testing two material test samples is provided. The fixture provides substantially equal shear and tensile stresses in each test specimens. By gradually applying a load force to the fixture only one of the two specimens fractures. Upon fracture of the one specimen, the fixture and the load train lose contact and the second specimen is preserved in a state of upset just prior to fracture. Particular advantages of the fixture are (1) to control the tensile to shear load on the specimen for understanding the effect of these stresses on the deformation behavior of advanced materials, (2) to control the location of fracture for accessing localized material properties including the variation of the mechanical properties and residual stresses across the thickness of advanced materials, (3) to yield a fractured specimen for strength measurement and an unfractured specimen for examining the microstructure just prior to fracture.

  13. Converting a Motorcycle to Electric Power

    E-Print Network [OSTI]

    Simcoe, Christopher M.

    2009-12-18

    Research was conducted to determine how simple and practical it would be to convert a standard gasoline powered motorcycle to electric power. The research involved background investigation of useful concepts in electric powered motorcycles...

  14. Transformer Synthesis for VHF Converters I. INTRODUCTION

    E-Print Network [OSTI]

    Perreault, Dave

    , such as a series resonance to replace the tank and transformer in a resonant converter [8], [9]. Such integrated increased loss due to flux shielding as compared to spiral designs. !"#$%&'"()'*%')$""% +,)+%-"./%011

  15. New Perspectives on Wave Energy Converter Control 

    E-Print Network [OSTI]

    Price, Alexandra A E

    2009-01-01

    This work examines some of the fundamental problems behind the control of wave energy converters (WECs). Several new perspectives are presented to aid the understanding of the problem and the interpretation of the ...

  16. Reversible shear thickening at low shear rates of electrorheological fluids under electric fields

    E-Print Network [OSTI]

    Yu Tian; Minliang Zhang; Jile Jiang; Noshir Pesika; Hongbo Zeng; Jacob Israelachvili; Yonggang Meng; Shizhu Wen

    2010-08-24

    Shear thickening is a phenomenon of significant viscosity increase of colloidal suspensions. While electrorheological (ER) fluids can be turned into a solid-like material by applying an electric field, their shear strength is widely represented by the attractive electrostatic interaction between ER particles. By shearing ER fluids between two concentric cylinders, we show a reversible shear thickening of ER fluids above a low critical shear rate (electric field strength (>100 V/mm), which could be characterized by a modified Mason number. Shear thickening and electrostatic particle interaction-induced inter-particle friction forces is considered to be the real origin of the high shear strength of ER fluids, while the applied electric field controls the extent of shear thickening. The electric field-controlled reversible shear thickening has implications for high-performance ER/magnetorheological (MR) fluid design, clutch fluids with high friction forces triggered by applying local electric field, other field-responsive materials and intelligent systems.

  17. Bi-directional dc-dc Converter | Department of Energy

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

    Maryland. merit08goodarzi.pdf More Documents & Publications WBG Converters and Chargers Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers Vehicle...

  18. Sheared

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect Photovoltaics -7541 Unlimited Release4:Seymour Sack,ShapeShareand

  19. Karen Shears | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRDEnergyTurbine blades being delivered to Kahuku. |Shears -

  20. Crystal Nucleation of Colloidal Suspensions under Shear

    E-Print Network [OSTI]

    Ronald Blaak; Stefan Auer; Daan Frenkel; Hartmut Lowen

    2004-06-10

    We use Brownian Dynamics simulations in combination with the umbrella sampling technique to study the effect of shear flow on homogeneous crystal nucleation. We find that a homogeneous shear rate leads to a significant suppression of the crystal nucleation rate and to an increase of the size of the critical nucleus. A simple, phenomenological extension of classical nucleation theory accounts for these observations. The orientation of the crystal nucleus is tilted with respect to the shear direction.

  1. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

    2002-01-01

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  2. Shear Thickening in Concentrated Soft Sphere Colloidal Suspensions: A Shear Induced Phase Transition

    E-Print Network [OSTI]

    Joachim Kaldasch; Bernhard Senge; Jozua Laven

    2015-01-09

    A model of shear thickening in dense suspensions of Brownian soft sphere colloidal particles is established. It suggests that shear thickening in soft sphere suspensions can be interpreted as a shear induced phase transition. Based on a Landau model of the coagulation transition of stabilized colloidal particles, taking the coupling between order parameter fluctuations and the local strain-field into account, the model suggests the occurrence of clusters of coagulated particles (subcritical bubbles) by applying a continuous shear perturbation.The critical shear stress of shear thickening in soft sphere suspensions is derived while reversible shear thickening and irreversible shear thickening have the same origin. The comparison of the theory with an experimental investigation of electrically stabilized colloidal suspensions confirms the presented approach.

  3. Novel shear mechanism in nanolayered composites

    SciTech Connect (OSTI)

    Mara, Nathan [Los Alamos National Laboratory; Bhattacharyya, Dhriti [Los Alamos National Laboratory; Hirth, John P [Los Alamos National Laboratory; Dickerson, Patricia O [Los Alamos National Laboratory; Misra, Amit [Los Alamos National Laboratory

    2009-01-01

    Recent studies have shown that two-phase nanocomposite materials with semicoherent interfaces exhibit enhanced strength, deformability, and radiation damage resistance. The remarkable behavior exhibited by these materials has been attributed to the atomistic structure of the bi-metal interface that results in interfaces with low shear strength and hence, strong barriers for slip transmission due to dislocation core spreading along the weak interfaces. In this work, the low interfacial shear strength of Cu/Nb nanoscale multilayers dictates a new mechanism for shear banding and strain softening during micropillar compression. Previous work investigating shear band formation in nanocrystalline materials has shown a connection between insufficient strain hardening and the onset of shear banding in Fe and Fe-10% Cu, but has also shown that hardening does not necessarily offset shear banding in Pd nanomaterials. Therefore, the mechanisms behind shear localization in nanocrystalline materials are not completely understood. Our findings, supported by molecular dynamics simulations, provide insight on the design of nanocomposites with tailored interface structures and geometry to obtain a combination of high strength and deformability. High strength is derived from the ability of the interfaces to trap dislocations through relative ease of interfacial shear, while deformability can be maximized by controlling the effects of loading geometry on shear band formation.

  4. Confined Cubic Blue Phases under Shear

    E-Print Network [OSTI]

    O. Henrich; K. Stratford; D. Marenduzzo; P. V. Coveney; M. E. Cates

    2012-03-14

    We study the behaviour of confined cubic blue phases under shear flow via lattice Boltzmann simulations. We focus on the two experimentally observed phases, blue phase I and blue phase II. The disinclination network of blue phase II continuously breaks and reforms under shear, leading to an oscillatory stress response in time. The oscillations are only regular for very thin samples. For thicker samples, the shear leads to a "stick-slip" motion of part of the network along the vorticity direction. Blue phase I responds very differently: its defect network undergoes seemingly chaotic rearrangements under shear, irrespective of system size.

  5. Low-rise shear wall failure modes

    SciTech Connect (OSTI)

    Farrar, C.R. (Los Alamos National Lab., NM (USA)); Hashimoto, P.S. (EQE Engineering, Inc., Costa Mesa, CA (USA)); Reed, J.W. (Benjamin (J.R.) and Associates, Inc., Mountain View, CA (USA))

    1991-01-01

    A summary of the data that are available concerning the structural response of low-rise shear walls is presented. This data will be used to address two failure modes associated with the shear wall structures. First, data concerning the seismic capacity of the shear walls with emphasis on excessive deformations that can cause equipment failure are examined. Second, data concerning the dynamic properties of shear walls (stiffness and damping) that are necessary to compute the seismic inputs to attached equipment are summarized. This case addresses the failure of equipment when the structure remains functional. 23 refs.

  6. Shear thickening in Electrically Stabilized Colloidal Suspensions

    E-Print Network [OSTI]

    Joachim Kaldasch; Bernhard Senge; Jozua Laven

    2011-07-25

    A theory is presented for the onset of shear thickening in colloidal suspensions of particles, stabilized by an electrostatic repulsion. Based on an activation model a critical shear stress can be derived for the onset of shear thickening in dense suspensions for a constant potential and a constant charge approach of the spheres. Unlike previous models the total interaction potential is taken into account (sum of attraction and repulsion). The critical shear stress is related to the maximum of the total interaction potential scaled by the free volume per particle. A comparison with experimental investigations shows the applicability of the theory.

  7. Shear Thickening in Polymer Stabilized Colloidal Suspensions

    E-Print Network [OSTI]

    Joachim Kaldasch; Bernhard Senge

    2012-07-11

    This paper adopts a previously developed activation model of shear thickening, published by the authors, to sterically stabilized colloidal suspensions. When particles arranged along the compression axis of a sheared suspension, they may overcome the repulsive interaction and form hydroclusters associated with shear thickening. Taking advantage of the total interaction potential of polymeric brush coating and van der Waals attraction, the applicability of the activation model is shown within the validity range of a continuum theory. For the comparison with an extensive experimental investigation, where some parameters are not available, the onset of shear thickening can be predicted with realistic assumptions of the model parameters.

  8. Power system applications for PASC converter systems

    SciTech Connect (OSTI)

    Donnelly, M.K.; Johnson, R.M.

    1994-04-01

    This paper shows, using computer EMTP simulations, some preliminary results of applying pulse amplitude synthesis and control (PASC) technology to single-source level voltage converter system. The method can be applied to any single terminal pair source with appropriate modifications in power extraction interface and computer control program to match source and load impedance characteristics. The PASC realization as discussed here employs banks of transformers, one bank per phase, in which the primaries are connected in parallel through a switch matrix to the dc source. Two opposite polarity primaries per transformer are pulsed alternatively in time to produce an oscillatory sinusoidal output waveform. PASC conversion system capabilities to produce both leading and lagging power factor power output in single-phase and three-phase {Delta} or Y configurations are illustrated. EMTP simulations are used to demonstrate the converter capabilities. Also included are discussions regarding harmonics and potential control strategies to adapt the converter to an application or to minimize harmonics.

  9. Study of Stability Regions in Parallel Connected Boost Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    Study of Stability Regions in Parallel Connected Boost Converters Yuehui Huang and Chi K. Tse attractors of parallel connected boost switching converters under a master- slave current sharing scheme. We boost converters. Under the master- slave scheme, one of the converters is the master and the other

  10. High-frequency matrix converter with square wave input

    DOE Patents [OSTI]

    Carr, Joseph Alexander; Balda, Juan Carlos

    2015-03-31

    A device for producing an alternating current output voltage from a high-frequency, square-wave input voltage comprising, high-frequency, square-wave input a matrix converter and a control system. The matrix converter comprises a plurality of electrical switches. The high-frequency input and the matrix converter are electrically connected to each other. The control system is connected to each switch of the matrix converter. The control system is electrically connected to the input of the matrix converter. The control system is configured to operate each electrical switch of the matrix converter converting a high-frequency, square-wave input voltage across the first input port of the matrix converter and the second input port of the matrix converter to an alternating current output voltage at the output of the matrix converter.

  11. On the shear instability of fluid interfaces

    E-Print Network [OSTI]

    A. Alexakis; Y. Young; R. Rosner

    2001-10-31

    We examine the linear stability of fluid interfaces subjected to a shear flow. Our main object is to generalize previous work to arbitrary Atwood number, and to allow for surface tension and weak compressibility. The motivation derives from instances in astrophysical systems where mixing across material interfaces driven by shear flows may significantly affect the dynamical evolution of these systems.

  12. Converting Centrifugal Chillers to HCFC-123 

    E-Print Network [OSTI]

    Siebert, B.

    1994-01-01

    of large water chillers in addressing the CFC issue. These owners, for a variety of reasons, chose to address the issue through the conversion of the existing equipment to an HCFC refrigerant. For each of the three owners, the option of converting...

  13. Hybrid switch for resonant power converters

    DOE Patents [OSTI]

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09

    A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

  14. Shear horizontal surface acoustic wave microsensor for Class...

    Office of Scientific and Technical Information (OSTI)

    Shear horizontal surface acoustic wave microsensor for Class A viral and bacterial detection. Citation Details In-Document Search Title: Shear horizontal surface acoustic wave...

  15. MULTILEVEL CONVERTERS - A NEW BREED OF POWER CONVERTERS Jih-Sheng...

    Office of Scientific and Technical Information (OSTI)

    has been a well-known method and has been implemented in 18- and 48-pulse converters for battery energy storage and static condenser (STATCON) applications, respectively 15,161....

  16. Joint environmental assessment for western NPR-1 3-dimensional seismic project at Naval Petroleum Reserve No. 1, Kern County, California

    SciTech Connect (OSTI)

    NONE

    1996-05-01

    The Department of Energy (DOE), in conjunction with the Bureau of Land Management (BLM), has prepared an Environmental Assessment (DOE/EA-1124) to identify and evaluate the potential environmental impacts of the proposed geophysical seismic survey on and adjacent to the Naval Petroleum Reserve No.1 (NPR-1), located approximately 35 miles west of Bakersfield, California. NPR-1 is jointly owned and operated by the federal government and Chevron U.S.A. Production Company. The federal government owns about 78 percent of NPR-1, while Chevron owns the remaining 22 percent. The government`s interest is under the jurisdiction of DOE, which has contracted with Bechtel Petroleum Operations, Inc. (BPOI) for the operation and management of the reserve. The 3-dimensional seismic survey would take place on NPR-1 lands and on public and private lands adjacent to NPR-1. This project would involve lands owned by BLM, California Department of Fish and Game (CDFG), California Energy Commission (CEC), The Nature Conservancy, the Center for Natural Lands Management, oil companies (Chevron, Texaco, and Mobil), and several private individuals. The proposed action is designed to provide seismic data for the analysis of the subsurface geology extant in western NPR-1 with the goal of better defining the commercial limits of a currently producing reservoir (Northwest Stevens) and three prospective hydrocarbon bearing zones: the {open_quotes}A Fan{close_quotes} in Section 7R, the 19R Structure in Section 19R, and the 13Z Structure in Section 13Z. Interpreting the data is expected to provide NPR-1 owners with more accurate locations of structural highs, faults, and pinchouts to maximize the recovery of the available hydrocarbon resources in western NPR-1. Completion of this project is expected to increase NPR-1 recoverable reserves, and reduce the risks and costs associated with further exploration and development in the area.

  17. Chondroregulatory action of prolactin on proliferation and differentiation of mouse chondrogenic ATDC5 cells in 3-dimensional micromass cultures

    SciTech Connect (OSTI)

    Seriwatanachai, Dutmanee [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand)] [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand); Krishnamra, Nateetip [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand) [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok (Thailand); Charoenphandhu, Narattaphol, E-mail: naratt@narattsys.com [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand) [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok (Thailand)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Mouse chondrogenic ATDC5 cells expressed PRL receptor mRNAs and proteins. Black-Right-Pointing-Pointer Low PRL concentration (10 ng/mL) increased chondrocyte viability and differentiation. Black-Right-Pointing-Pointer Higher PRL concentrations ( Greater-Than-Or-Slanted-Equal-To 100 ng/mL) decreased viability and increased apoptosis. -- Abstract: A recent investigation in lactating rats has provided evidence that the lactogenic hormone prolactin (PRL) increases endochondral bone growth and bone elongation, presumably by accelerating apoptosis of hypertrophic chondrocytes in the growth plate and/or subsequent chondrogenic matrix mineralization. Herein, we demonstrated the direct chondroregulatory action of PRL on proliferation, differentiation and apoptosis of chondrocytes in 3-dimensional micromass culture of mouse chondrogenic ATDC5 cell line. The results showed that ATDC5 cells expressed PRL receptor (PRLR) transcripts, and responded typically to PRL by downregulating PRLR expression. Exposure to a low PRL concentration of 10 ng/mL, comparable to the normal levels in male and non-pregnant female rats, increased chondrocyte viability, differentiation, proteoglycan accumulation, and mRNA expression of several chondrogenic differentiation markers, such as Sox9, ALP and Hspg2. In contrast, high PRL concentrations of Greater-Than-Or-Slanted-Equal-To 100 ng/mL, comparable to the levels in pregnancy or lactation, decreased chondrocyte viability by inducing apoptosis, with no effect on chondrogenic marker expression. It could be concluded that chondrocytes directly but differentially responded to non-pregnant and pregnant/lactating levels of PRL, thus suggesting the stimulatory effect of PRL on chondrogenesis in young growing individuals, and supporting the hypothesis of hypertrophic chondrocyte apoptosis in the growth plate of lactating rats.

  18. Optical analog-to-digital converter

    DOE Patents [OSTI]

    Vawter, G. Allen (Corrales, NM); Raring, James (Goleta, CA); Skogen, Erik J. (Albuquerque, NM)

    2009-07-21

    An optical analog-to-digital converter (ADC) is disclosed which converts an input optical analog signal to an output optical digital signal at a sampling rate defined by a sampling optical signal. Each bit of the digital representation is separately determined using an optical waveguide interferometer and an optical thresholding element. The interferometer uses the optical analog signal and the sampling optical signal to generate a sinusoidally-varying output signal using cross-phase-modulation (XPM) or a photocurrent generated from the optical analog signal. The sinusoidally-varying output signal is then digitized by the thresholding element, which includes a saturable absorber or at least one semiconductor optical amplifier, to form the optical digital signal which can be output either in parallel or serially.

  19. Converting DYNAMO simulations to Powersim Studio simulations

    SciTech Connect (OSTI)

    Walker, La Tonya Nicole; Malczynski, Leonard A.

    2014-02-01

    DYNAMO is a computer program for building and running 'continuous' simulation models. It was developed by the Industrial Dynamics Group at the Massachusetts Institute of Technology for simulating dynamic feedback models of business, economic, and social systems. The history of the system dynamics method since 1957 includes many classic models built in DYANMO. It was not until the late 1980s that software was built to take advantage of the rise of personal computers and graphical user interfaces that DYNAMO was supplanted. There is much learning and insight to be gained from examining the DYANMO models and their accompanying research papers. We believe that it is a worthwhile exercise to convert DYNAMO models to more recent software packages. We have made an attempt to make it easier to turn these models into a more current system dynamics software language, Powersim © Studio produced by Powersim AS2 of Bergen, Norway. This guide shows how to convert DYNAMO syntax into Studio syntax.

  20. Component technology for Stirling power converters

    SciTech Connect (OSTI)

    Thieme, L.G.

    1994-09-01

    NASA Lewis Research Center has organized a component technology program as part of the efforts to develop Stirling converter technology for space power applications. The Stirling space power program is part of the NASA High Capacity Power Project of the Civil Space Technology Initiative (CSTI). NASA Lewis is also providing technical management for a DOE/Sandia program to develop Stirling converters for solar terrestrial power producing electricity for the utility grid. The primary contractors for the space power and solar terrestrial programs develop component technologies directly related to their program goals. This Lewis component technology effort, while coordinated with the main programs, aims at longer term issues, advanced technologies, and independent assessments. This paper will present an overview of work on linear alternators, engine/alternator/load interactions and controls, heat exchangers, materials, life and reliability, and bearings.

  1. Kinematics of compressional and extensional ductile shearing...

    Open Energy Info (EERE)

    domains of the middle and lower crust through the ductile shear zones localized at the Precambrian-Paleozoic interface. This extension of the middle and lower crust occurred in...

  2. The effect of shear on neurodegeneration 

    E-Print Network [OSTI]

    Triyoso, Dina Handayani

    1998-01-01

    induced neurodegeneration was established in order to elucidate the mechanism of neurodegeneration in glaucomas hydrocephalus and head injury. The model consisted of a differentiated human neuroblastoma cell line, SH-SY5Y, which was exposed to shear...

  3. Mesoscale Elucidation of Biofilm Shear Behavior

    E-Print Network [OSTI]

    Barai, Pallab; Mukherjee, Partha P

    2015-01-01

    Formation of bacterial colonies as biofilm on the surface/interface of various objects has the potential to impact not only human health and disease but also energy and environmental considerations. Biofilms can be regarded as soft materials, and comprehension of their shear response to external forces is a key element to the fundamental understanding. A mesoscale model has been presented in this article based on digitization of a biofilm microstructure. Its response under externally applied shear load is analyzed. Strain stiffening type behavior is readily observed under high strain loads due to the unfolding of chains within soft polymeric substrate. Sustained shear loading of the biofilm network results in strain localization along the diagonal direction. Rupture of the soft polymeric matrix can potentially reduce the intercellular interaction between the bacterial cells. Evolution of stiffness within the biofilm network under shear reveals two regions: a) initial increase in stiffness due to strain stiffe...

  4. Turbulence Modeling for Compressible Shear Flows 

    E-Print Network [OSTI]

    Gomez Elizondo, Carlos Arturo 1981-

    2012-11-15

    by requiring consistency between model and direct numerical simulation asymptotic behavior in compressible homogeneous shear flow. The closure models are employed to compute high-speed mixing-layers and boundary layers in a differential Reynolds stress modeling...

  5. Heat Pump Water Heater using Solid-State Energy Converters |...

    Energy Savers [EERE]

    Heat Pump Water Heater using Solid-State Energy Converters Heat Pump Water Heater using Solid-State Energy Converters Sheetak will work on developing a full scale prototype of its...

  6. An economical single to three phase converter for induction motors 

    E-Print Network [OSTI]

    Di Zerega, Philp Van Uytandaele

    1994-01-01

    There are several different types of single to three phase converters for induction motors available today. However, many of the presently available phase converters suffer from disadvantages such as high cost or low performance. An economical...

  7. DOE Announces Webinars on the Wave Energy Converter Prize, the...

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

    the Wave Energy Converter Prize, the Best of the Clean Cities Tools and Resources, and More DOE Announces Webinars on the Wave Energy Converter Prize, the Best of the Clean Cities...

  8. Digital radix converters for high accuracy data conversion 

    E-Print Network [OSTI]

    Ghanta, Venkataratnam Chowdary

    1993-01-01

    A sub-binary radix Digital to Analog converter(DAC) which achieves high effective resolution is demonstrated. The converter does not have any built-in-self calibration mechanisms, but achieves high resolution and accuracy through the sub...

  9. Shear dispersion in dense granular flows

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

    Christov, Ivan C.; Stone, Howard A.

    2014-04-18

    We formulate and solve a model problem of dispersion of dense granular materials in rapid shear flow down an incline. The effective dispersivity of the depth-averaged concentration of the dispersing powder is shown to vary as the Péclet number squared, as in classical Taylor–Aris dispersion of molecular solutes. An extension to generic shear profiles is presented, and possible applications to industrial and geological granular flows are noted.

  10. Liquid migration in sheared unsaturated granular media

    E-Print Network [OSTI]

    Roman Mani; Dirk Kadau; Hans J. Herrmann

    2012-06-25

    We show how liquid migrates in sheared unsaturated granular media using a grain scale model for capillary bridges. Liquid is redistributed to neighboring contacts after rupture of individual capillary bridges leading to redistribution of liquid on large scales. The liquid profile evolution coincides with a recently developed continuum description for liquid migration in shear bands. The velocity profiles which are linked to the migration of liquid as well as the density profiles of wet and dry granular media are studied.

  11. Accurate shear measurement with faint sources

    SciTech Connect (OSTI)

    Zhang, Jun; Foucaud, Sebastien; Luo, Wentao E-mail: walt@shao.ac.cn

    2015-01-01

    For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be measured accurately in Fourier space in the presence of background noise and finite pixel size, without assumptions on the morphologies of galaxy and PSF. The remaining major source of error is source Poisson noise, due to the finiteness of source photon number. This problem is particularly important for faint galaxies in space-based weak lensing measurements, and for ground-based images of short exposure times. In this work, we propose a simple and rigorous way of removing the shear bias from the source Poisson noise. Our noise treatment can be generalized for images made of multiple exposures through MultiDrizzle. This is demonstrated with the SDSS and COSMOS/ACS data. With a large ensemble of mock galaxy images of unrestricted morphologies, we show that our shear measurement method can achieve sub-percent level accuracy even for images of signal-to-noise ratio less than 5 in general, making it the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.

  12. Statistics of polymer adsorption under shear flow

    E-Print Network [OSTI]

    Gui-Li He; René Messina; Hartmut Löwen

    2009-10-09

    Using non-equilibrium Brownian dynamics computer simulations, we have investigated the steady state statistics of a polymer chain under three different shear environments: i) linear shear flow in the bulk (no walls), ii) shear vorticity normal to the adsorbing wall, iii) shear gradient normal to the adsorbing wall. The statistical distribution of the chain end-to-end distance and its orientational angles are calculated within our monomer-resolved computer simulations. Over a wide range of shear rates, this distribution can be mapped onto a simple theoretical finite-extensible-nonlinear-elastic dumbbell model with fitted anisotropic effective spring constants. The tails of the angular distribution functions are consistent with scaling predictions borrowed from the bulk dumbbell model. Finally, the frequency of the characteristic periodic tumbling motion has been investigated by simulation as well and was found to be sublinear with the shear rate for the three set-ups, which extends earlier results done in experiments and simulations for free and tethered polymer molecules without adsorption.

  13. Large Deformation of Nitinol Under Shear Dominant Loading

    E-Print Network [OSTI]

    Daly, Samantha

    Large Deformation of Nitinol Under Shear Dominant Loading S. Daly & D. Rittel & K. Bhattacharya & G in Nitinol under large shear- dominated deformation are presented. To achieve a shear- dominated deformation transformation that is seen in uniaxial testing. The shear-dominant deformation of Nitinol in the plastic regime

  14. Aalborg Universitet Single stage grid converters for battery energy storage

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet Single stage grid converters for battery energy storage Trintis, Ionut; Munk). Single stage grid converters for battery energy storage. In 5th IET International Conference on Power from vbn.aau.dk on: juli 04, 2015 #12;SINGLE STAGE GRID CONVERTERS FOR BATTERY ENERGY STORAGE I

  15. Optimizing Ballast Design of Wave Energy Converters Using Evolutionary Algorithms

    E-Print Network [OSTI]

    Tumer, Kagan

    Optimizing Ballast Design of Wave Energy Converters Using Evolutionary Algorithms Mitch Colby, 97331 kagan.tumer@oregonstate.edu ABSTRACT Wave energy converters promise to be a viable alternative% improvement in power output over a ballast-free wave energy converter. General Terms Algorithms; Applications

  16. General Impedance Synthesizer Using Minimal Configuration of Switching Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    converter may contain a storage element and a pair of switches, such as the buck, buck-boost and boostGeneral Impedance Synthesizer Using Minimal Configuration of Switching Converters Joe C.P. Liu Chi a minimum number of switching converters is stud- ied in this paper. We begin with showing that any

  17. Design Methodology for a Very High Frequency Resonant Boost Converter

    E-Print Network [OSTI]

    Perreault, Dave

    Design Methodology for a Very High Frequency Resonant Boost Converter Justin M. Burkhart , Roman@ti.com Abstract--This document introduces a design methodology for a resonant boost converter topology demonstrated for boost conversion at frequencies up to 110MHz using a resonant boost converter topology in [5

  18. Coupled Dual Interleaved Flyback Converter for High Input Voltage Application

    E-Print Network [OSTI]

    Lehman, Brad

    proposed integrated boost converters [7] that are beginning to see applications in automotive power buck-boost (Flyback) power converter [9,10] that utilizes one magnetic core to integrate two FlybackCoupled Dual Interleaved Flyback Converter for High Input Voltage Application Ting Qian, Brad

  19. Modelling and geometry optimisation of wave energy converters

    E-Print Network [OSTI]

    Nørvåg, Kjetil

    Modelling and geometry optimisation of wave energy converters Adi Kurniawan Supervisors: Prof;Research questions Modelling How to develop more realistic wave energy converter (WEC) models while wave energy converter (WEC) models while at the same time reduce their simulation time? Optimisation

  20. Reconstruction 3-dimensional image from 2-dimensional image of status optical coherence tomography (OCT) for analysis of changes in retinal thickness

    SciTech Connect (OSTI)

    Arinilhaq,; Widita, Rena [Department of Physics, Nuclear Physics and Biophysics Research Group, Institut Teknologi Bandung (Indonesia)

    2014-09-30

    Optical Coherence Tomography is often used in medical image acquisition to diagnose that change due easy to use and low price. Unfortunately, this type of examination produces a two-dimensional retinal image of the point of acquisition. Therefore, this study developed a method that combines and reconstruct 2-dimensional retinal images into three-dimensional images to display volumetric macular accurately. The system is built with three main stages: data acquisition, data extraction and 3-dimensional reconstruction. At data acquisition step, Optical Coherence Tomography produced six *.jpg images of each patient were further extracted with MATLAB 2010a software into six one-dimensional arrays. The six arrays are combined into a 3-dimensional matrix using a kriging interpolation method with SURFER9 resulting 3-dimensional graphics of macula. Finally, system provides three-dimensional color graphs based on the data distribution normal macula. The reconstruction system which has been designed produces three-dimensional images with size of 481 × 481 × h (retinal thickness) pixels.

  1. Resource convertibility and ordered commutative monoids

    E-Print Network [OSTI]

    Tobias Fritz

    2015-07-02

    Resources and their use and consumption form a central part of our life. Many branches of science and engineering are concerned with the question of which given resource objects can be converted into which target resource objects. For example, information theory studies the conversion of a noisy communication channel instance into an exchange of information. Inspired by work in quantum information theory, we develop a general mathematical toolbox for this type of question. The convertibility of resources into other ones and the possibility of combining resources is accurately captured by the mathematics of ordered commutative monoids. As an intuitive example, we consider chemistry, where chemical reaction equations such as \\[ \\mathrm{2H_2 + O_2} \\to \\mathrm{2H_2O} \\] are concerned both with a convertibility relation "$\\to$" and a combination operation "$+$". We study ordered commutative monoids from an algebraic and functional-analytic perspective and derive a wealth of results which should have applications to concrete resource theories, such as a formula for rates of conversion. As a running example showing that ordered commutative monoids are also of purely mathematical interest, we exemplify our results with the ordered commutative monoid of graphs. While closely related to both Girard's linear logic and to Deutsch's constructor theory, our framework also produces results very reminiscent of the utility theorem of von Neumann and Morgenstern in decision theory and of a theorem of Lieb and Yngvason on thermodynamics. Concerning pure algebra, our observation is that some pieces of algebra can be developed in a context in which equality is not necessarily symmetric, i.e. in which the equality relation is replaced by an ordering relation. For example, notions like cancellativity or torsion-freeness are still sensible and very natural concepts in our ordered setting.

  2. Voltage balanced multilevel voltage source converter system

    DOE Patents [OSTI]

    Peng, F.Z.; Lai, J.S.

    1997-07-01

    Disclosed is a voltage balanced multilevel converter for high power AC applications such as adjustable speed motor drives and back-to-back DC intertie of adjacent power systems. This converter provides a multilevel rectifier, a multilevel inverter, and a DC link between the rectifier and the inverter allowing voltage balancing between each of the voltage levels within the multilevel converter. The rectifier is equipped with at least one phase leg and a source input node for each of the phases. The rectifier is further equipped with a plurality of rectifier DC output nodes. The inverter is equipped with at least one phase leg and a load output node for each of the phases. The inverter is further equipped with a plurality of inverter DC input nodes. The DC link is equipped with a plurality of rectifier charging means and a plurality of inverter discharging means. The plurality of rectifier charging means are connected in series with one of the rectifier charging means disposed between and connected in an operable relationship with each adjacent pair of rectifier DC output nodes. The plurality of inverter discharging means are connected in series with one of the inverter discharging means disposed between and connected in an operable relationship with each adjacent pair of inverter DC input nodes. Each of said rectifier DC output nodes are individually electrically connected to the respective inverter DC input nodes. By this means, each of the rectifier DC output nodes and each of the inverter DC input nodes are voltage balanced by the respective charging and discharging of the rectifier charging means and the inverter discharging means. 15 figs.

  3. Converting urban tree maintenance residue to energy

    SciTech Connect (OSTI)

    Murphey, W.K.; Massey, J.G.; Sumrall, A.

    1980-01-01

    Three methods of utilizing urban wood waste collected by a tree maintenance firm in Houston, Texas (handling 30,000 ton waste/year) are examined: (a) hauling to a remote landfill; (b) chipping and hauling to a (local) power plant and converting to electricity; and (c) chipping and selling to an outside firm for use as boiler fuel. Breakdown of costs are given for each method in monetary and energy terms. Method (b) was the cheapest, producing a net energy gain (870 million Btu/day), but the firm chose method (c), since it realized a direct monetary return.

  4. Solid state transport-based thermoelectric converter

    DOE Patents [OSTI]

    Hu, Zhiyu

    2010-04-13

    A solid state thermoelectric converter includes a thermally insulating separator layer, a semiconducting collector and an electron emitter. The electron emitter comprises a metal nanoparticle layer or plurality of metal nanocatalyst particles disposed on one side of said separator layer. A first electrically conductive lead is electrically coupled to the electron emitter. The collector layer is disposed on the other side of the separator layer, wherein the thickness of the separator layer is less than 1 .mu.m. A second conductive lead is electrically coupled to the collector layer.

  5. TRACKING OF SHEAR BANDS IN AN ANTIPLANE SHEAR MODEL F. XABIER GARAIZAR AND JOHN TRANGENSTEIN

    E-Print Network [OSTI]

    ­trivial component of the velocity vector is in the z­direction. When the material reaches a critical value of loading, shear banding occurs. While the overall defor­ mation is described by a hyperbolic system of equations, hyperbolicity is lost at the points when shear banding occurs. At these points, the deformation

  6. CCLIBS: The CERN Power Converter Control Libraries

    E-Print Network [OSTI]

    King, Quentin; Magrans De Abril, Marc; Martino, Michele; Murillo Garcia, Raul; Nicoletti, Achille

    2015-01-01

    Accurate control of power converters is a vital activity in large physics projects. Several different control scenarios may coexist, including regulation of a circuit’s voltage, current, or field strength within a magnet. Depending on the type of facility, a circuit’s reference value may be changed asynchronously or synchronously with other circuits. Synchronous changes may be on demand or under the control of a cyclic timing system. In other cases, the reference may be calculated in real-time by an outer regulation loop of some other quantity, such as the tune of the beam in a synchrotron. The power stage may be unipolar or bipolar in voltage and current. If it is unipolar in current, it may be used with a polarity switch. Depending on the design, the power stage may be controlled by a firing angle or PWM duty-cycle reference, or a voltage or current reference. All these cases are supported by the CERN Converter Control Libraries (CCLIBS). These open-source C libraries include advanced reference generati...

  7. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    Power Maximization in Wave-Energy Converters Using Sampled-design optimization of wave energy converters con- sistingN. Sahinkaya. A review of wave energy converter technology.

  8. Pressure-shear experiments on granular materials.

    SciTech Connect (OSTI)

    Reinhart, William Dodd; Thornhill, Tom Finley, III; Vogler, Tracy John; Alexander, C. Scott

    2011-10-01

    Pressure-shear experiments were performed on granular tungsten carbide and sand using a newly-refurbished slotted barrel gun. The sample is a thin layer of the granular material sandwiched between driver and anvil plates that remain elastic. Because of the obliquity, impact generates both a longitudinal wave, which compresses the sample, and a shear wave that probes the strength of the sample. Laser velocity interferometry is employed to measure the velocity history of the free surface of the anvil. Since the driver and anvil remain elastic, analysis of the results is, in principal, straightforward. Experiments were performed at pressures up to nearly 2 GPa using titanium plates and at higher pressure using zirconium plates. Those done with the titanium plates produced values of shear stress of 0.1-0.2 GPa, with the value increasing with pressure. On the other hand, those experiments conducted with zirconia anvils display results that may be related to slipping at an interface and shear stresses mostly at 0.1 GPa or less. Recovered samples display much greater particle fracture than is observed in planar loading, suggesting that shearing is a very effective mechanism for comminution of the grains.

  9. Shear Viscosity of a Hot Pion Gas

    E-Print Network [OSTI]

    Robert Lang; Norbert Kaiser; Wolfram Weise

    2012-09-04

    The shear viscosity of an interacting pion gas is studied using the Kubo formalism as a microscopic description of thermal systems close to global equilibrium. We implement the skeleton expansion in order to approximate the retarded correlator of the viscous part of the energy-momentum tensor. After exploring this in $g\\phi^4$ theory we show how the skeleton expansion can be consistently applied to pions in chiral perturbation theory. The shear viscosity $\\eta$ is determined by the spectral width, or equivalently, the mean free path of pions in the heat bath. We derive a new analytical result for the mean free path which is well-conditioned for numerical evaluation and discuss the temperature and pion-mass dependence of the mean free path and the shear viscosity. The ratio $\\eta/s$ of the interacting pion gas exceeds the lower bound $1/4\\pi$ from AdS/CFT correspondence.

  10. Transport Physics in Reversed Shear Plasmas

    SciTech Connect (OSTI)

    Levinton, F.M.; Batha, S.H.; Beer, M.A.; Bell, M.G.; Budny, R.V.; Efthimion, P.C.; Mazzucato, E.; Nazikian, R.; Park, H.K.; Ramsey, A.T.; Schmidt, G.L.; Scott, S.D.; Synakowski, E.J.; Taylor, G.; Von Goeler, S.; Zarnstorff, M.C.; Bush, C.E.

    1997-12-31

    Reversed magnetic shear is considered a good candidate for improving the tokamak concept because it has the potential to stabilize MHD instabilities and reduce particle and energy transport. With reduced transport the high pressure gradient would generate a strong off-axis bootstrap current and could sustain a hollow current density profile. Such a combination of favorable conditions could lead to an attractive steady-state tokamak configuration. Indeed, a new tokamak confinement regime with reversed magnetic shear has been observed on the Tokamak Fusion Test Reactor (TFTR) where the particle, momentum, and ion thermal diffusivities drop precipitously, by over an order of magnitude. The particle diffusivity drops to the neoclassical level and the ion thermal diffusivity drops to much less than the neoclassical value in the region with reversed shear. This enhanced reversed shear (ERS) confinement mode is characterized by an abrupt transition with a large rate of rise of the density in the reversed shear region during neutral beam injection, resulting in nearly a factor of three increase in the central density to 1.2 X 10(exp 20) cube m. At the same time the density fluctuation level in the reversed shear region dramatically decreases. The ion and electron temperatures, which are about 20 keV and 7 keV respectively, change little during the ERS mode. The transport and transition into and out of the ERS mode have been studied on TFTR with plasma currents in the range 0.9-2.2 MA, with a toroidal magnetic field of 2.7-4.6 T, and the radius of the q(r) minimum, q{sub min}, has been varied from r/a = 0.35 to 0.55. Toroidal field and co/counter neutral beam injection toroidal rotation variations have been used to elucidate the underlying physics of the transition mechanism and power threshold of the ERS mode.

  11. Converting energy from fusion into useful forms

    E-Print Network [OSTI]

    Kovari, M; Jenkins, I; Kiely, C

    2014-01-01

    If fusion power reactors are to be feasible, it will still be necessary to convert the energy of the nuclear reaction into usable form. The heat produced will be removed from the reactor core by a primary coolant, which might be water, helium, molten lithium-lead, molten lithium-containing salt, or CO2. The heat could then be transferred to a conventional Rankine cycle or Brayton (gas turbine) cycle. Alternatively it could be used for thermochemical processes such as producing hydrogen or other transport fuels. Fusion presents new problems because of the high energy neutrons released. These affect the selection of materials and the operating temperature, ultimately determining the choice of coolant and working cycle. The limited temperature ranges allowed by present day irradiated structural materials, combined with the large internal power demand of the plant, will limit the overall thermal efficiency. The operating conditions of the fusion power source, the materials, coolant, and energy conversion system w...

  12. Mechanical vibration to electrical energy converter

    DOE Patents [OSTI]

    Kellogg, Rick Allen (Tijeras, NM); Brotz, Jay Kristoffer (Albuquerque, NM)

    2009-03-03

    Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.

  13. Modular Power Converters for PV Applications

    SciTech Connect (OSTI)

    Ozpineci, Burak; Tolbert, Leon M

    2012-05-01

    This report describes technical opportunities to serve as parts of a technological roadmap for Shoals Technologies Group in power electronics for PV applications. There are many different power converter circuits that can be used for solar inverter applications. The present applications do not take advantage of the potential for using common modules. We envision that the development of a power electronics module could enable higher reliability by being durable and flexible. Modules would have fault current limiting features and detection circuits such that they can limit the current through the module from external faults and can identify and isolate internal faults such that the remaining modules can continue to operate with only minimal disturbance to the utility or customer. Development of a reliable, efficient, low-cost, power electronics module will be a key enabling technology for harnessing more power from solar panels and enable plug and play operation. Power electronics for computer power supplies, communication equipment, and transportation have all targeted reliability and modularity as key requirements and have begun concerted efforts to replace monolithic components with collections of common smart modules. This is happening on several levels including (1) device level with intelligent control, (2) functional module level, and (3) system module. This same effort is needed in power electronics for solar applications. Development of modular units will result in standard power electronic converters that will have a lower installed and operating cost for the overall system. These units will lead to increased adaptability and flexibility of solar inverters. Incorporating autonomous fault current limiting and reconfiguration capabilities into the modules and having redundant modules will lead to a durable converter that can withstand the rigors of solar power generation for more than 30 years. Our vision for the technology roadmap is that there is no need for detailed design of new power converters for each new application or installation. One set of modules and controllers can be pre-developed and the only design question would be how many modules need to be in series or parallel for the specific power requirement. Then, a designer can put the modules together and add the intelligent reconfigurable controller. The controller determines how many modules are connected, but it might also ask for user input for the specific application during setup. The modules include protection against faults and can reset it, if necessary. In case of a power device failure, the controller reconfigures itself to continue limited operation until repair which might be as simple as taking the faulty module out and inserting a new module. The result is cost savings in design, maintenance, repair, and a grid that is more reliable and available. This concept would be a perfect fit for the recently announced funding opportunity announcement (DE-FOA-0000653) on Plug and Play Photovoltaics.

  14. Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter

    SciTech Connect (OSTI)

    2012-02-09

    Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

  15. SUPERSONIC SHEAR INSTABILITIES IN ASTROPHYSICAL BOUNDARY LAYERS

    SciTech Connect (OSTI)

    Belyaev, Mikhail A.; Rafikov, Roman R., E-mail: rrr@astro.princeton.edu [Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08540 (United States)

    2012-06-20

    Disk accretion onto weakly magnetized astrophysical objects often proceeds via a boundary layer (BL) that forms near the object's surface, in which the rotation speed of the accreted gas changes rapidly. Here, we study the initial stages of formation for such a BL around a white dwarf or a young star by examining the hydrodynamical shear instabilities that may initiate mixing and momentum transport between the two fluids of different densities moving supersonically with respect to each other. We find that an initially laminar BL is unstable to two different kinds of instabilities. One is an instability of a supersonic vortex sheet (implying a discontinuous initial profile of the angular speed of the gas) in the presence of gravity, which we find to have a growth rate of order (but less than) the orbital frequency. The other is a sonic instability of a finite width, supersonic shear layer, which is similar to the Papaloizou-Pringle instability. It has a growth rate proportional to the shear inside the transition layer, which is of order the orbital frequency times the ratio of stellar radius to the BL thickness. For a BL that is thin compared to the radius of the star, the shear rate is much larger than the orbital frequency. Thus, we conclude that sonic instabilities play a dominant role in the initial stages of nonmagnetic BL formation and give rise to very fast mixing between disk gas and stellar fluid in the supersonic regime.

  16. SEP Success Story: State Energy Program Helping Arkansans Convert...

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

    to purchase andor convert their Arkansas-licensed vehicles to compressed natural gas (CNG). | All Rights Reserved. The Arkansas Energy Office recently launched a Compressed...

  17. Sandia Energy - Advanced Controls of Wave Energy Converters May...

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

    Advanced Controls of Wave Energy Converters May Increase Power Capture Up to 330% Home Renewable Energy Energy Water Power Partnership News News & Events Computational Modeling &...

  18. NREL Refines Method to Convert Lignin to Nylon Precursor - News...

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

    to Convert Lignin to Nylon Precursor Recent Findings Published in Energy & Environmental Science February 26, 2015 A new study from the Energy Department's National Renewable...

  19. Secretary Chu Announces Six Projects to Convert Captured CO2...

    Energy Savers [EERE]

    that Americans can use. "These innovative projects convert carbon pollution from a climate threat to an economic resource," said Secretary Chu. "This is part of our broad...

  20. Wave Energy Converter Effects on Nearshore Wave Propagation

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

    Energy Converter Effects on Nearshore Wave Propagation Jesse Roberts 1 , Grace Chang *2 , Craig Jones *3 Sandia National Laboratories 1515 Eubank SE, Albuquerque, NM 87123 USA 1...

  1. Sandia Energy - Sandia, NREL Release Wave Energy Converter Modeling...

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

    Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim Home Renewable Energy Energy Water Power Partnership News News & Events Computational Modeling & Simulation...

  2. Improved Low-Temperature Performance of Catalytic Converters...

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

    National Laboratory. Toxic vehicle emissions, such as carbon monoxide and unburned hydrocarbons, are chemically converted to benign compounds, like carbon dioxide (CO2) and water,...

  3. Shear and Extensional Rheology of Cellulose/Ionic Liquid Solutions

    E-Print Network [OSTI]

    Haward, Simon J.

    In this study, we characterize the shear and extensional rheology of dilute to semidilute solutions of cellulose in the ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIAc). In steady shear flow, the semidilute solutions ...

  4. Switching power converter Figure 1(a): Switching DC-DC converter with analog voltage-mode control

    E-Print Network [OSTI]

    + ­ RC L Vg 1 2 i + v _ Vref + _ Gc(s) VM = 1 PWM u c Switching power converter H v dTs H = 1 design of digital compensators. I. INTRODUCTION Discrete-time modeling of dc-dc switching converters has IEEE. #12;+ ­ R C L Vg 1 2 i + v _ Vref + _ Gc(z) VM = 1 DPWM u c Switching power converter H v dTs H

  5. Spatially-resolved microstructure in shear banding wormlike micellar solutions

    SciTech Connect (OSTI)

    Helgeson, Matthew E.; Reichert, Matthew D.; Wagner, Norman J.; Kaler, Eric W. [Department of Chemical Engineering, University of Delaware, Newark, DE 19716 (United States)

    2008-07-07

    Recently proposed theories for shear banding in wormlike micellar solutions (WLMs) rely on a shear-induced isotropic-nematic (I-N) phase separation as the mechanism for banding. Critical tests of such theories require spatially-resolved measurements of flow-kinematics and local mesoscale microstructure within the shear bands. We have recently developed such capabilities using a short gap Couette cell for flow-small angle neutron scattering (flow-SANS) measurements in the 1-2 plane of shear with collaborators at the NIST Center for Neutron Research. This work combines flow-SANS measurements with rheology, rheo-optics and velocimetry measurements to present the first complete spatially-resolved study of WLMs through the shear banding transition for a model shear banding WLM solution near the I-N phase boundary. The shear rheology is well-modeled by the Giesekus constitutive equation, with incorporated stress diffusion to predict shear banding. By fitting the stress diffusivity at the onset of banding, the model enables prediction of velocity profiles in the shear banded state which are in quantitative agreement with measured flow-kinematics. Quantitative analysis of the flow-SANS measurements shows a critical segmental alignment for banding and validates the Giesekus model predictions, linking segmental orientation to shear banding and providing the first rigorous evidence for the shear-induced I-N transition mechanism for shear banding.

  6. Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1

    E-Print Network [OSTI]

    Li, Tim

    Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1 Tim Li,1,2 and Xiaqiong Zhou1] Tropical cyclone Rossby wave energy dispersion under easterly and westerly vertical shears is investigated, and X. Zhou (2007), Tropical cyclone energy dispersion under vertical shears, Geophys. Res. Lett., 34, L

  7. TURBULENT SHEAR STRESS IN HETEROGENEOUS SEDIMENT-LADEN FLOWS

    E-Print Network [OSTI]

    Julien, Pierre Y.

    TURBULENT SHEAR STRESS IN HETEROGENEOUS SEDIMENT-LADEN FLOWS By Hyoseop Woo,1 Associate Member are the beginning of motion of sediment particles and sediment transport in alluvial channels. If shear stress can be well defined in clear-water flows, compar- atively little is known about shear stresses in sediment

  8. Active Vibration Suppression of Sandwich Beams using Piezoelectric Shear Actuators

    E-Print Network [OSTI]

    Vel, Senthil

    on the effectiveness of the piezo- electric shear mechanism for active vibration suppression. In this paper, weActive Vibration Suppression of Sandwich Beams using Piezoelectric Shear Actuators Senthil S. Vel1 of the piezoelectric actuators to cause transverse shear deformation of the sandwich beam. Active vibration suppression

  9. Full-tensor alignment criteria for sheared nematic polymers

    E-Print Network [OSTI]

    Full-tensor alignment criteria for sheared nematic polymers M. Gregory Forest and Ruhai Zhou The shear problem for nematic polymers consists in characterizing all stable stationary ori- entational, further characterize nematic polymers in simple shear. Leslie-Ericksen (L-E) theory provides formulas

  10. Harmonic Elimination for Multilevel Converter with Programmed PWM Method

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Harmonic Elimination for Multilevel Converter with Programmed PWM Method Zhong Du, Leon M. Tolbert presents a programmed PWM method to eliminate specific higher order harmonics of multilevel converters. First, resultant theory is applied to transcendental equations to eliminate low order harmonics

  11. IEEE INFOCOM 2002 1 Design of Wavelength Converting Switches for

    E-Print Network [OSTI]

    Turner, Jonathan S.

    IEEE INFOCOM 2002 1 Design of Wavelength Converting Switches for Optical Burst Switching Jeyashankher Ramamirtham, Jonathan Turner Abstract-- Optical Burst Switching (OBS) is an experi- mental network- tronic control. In this paper, we study two designs for wave- length converting switches

  12. Design of Wavelength Converting Switches for Optical Burst Switching

    E-Print Network [OSTI]

    Design of Wavelength Converting Switches for Optical Burst Switching Jeyashankher Ramamirtham, Jonathan Turner Abstract-- Optical Burst Switching (OBS) is an experi- mental network technology. In this paper, we study two designs for wavelength converting switches that are suitable for use in optical

  13. Semiconductors 8-bit multiplying D/A converter

    E-Print Network [OSTI]

    Gustafsson, Torgny

    Philips Semiconductors MC1408-8 8-bit multiplying D/A converter Product data Supersedes data of 1994 Aug 31 File under Integrated Circuits, IC11 Handbook 2001 Aug 03 INTEGRATED CIRCUITS #12;Philips Semiconductors Product data MC1408-88-bit multiplying D/A converter 22001 Aug 03 853-0935 26835 DESCRIPTION

  14. Minimum Phase Response in Digitally Controlled Boost and Flyback Converters

    E-Print Network [OSTI]

    -frequency switching power converters has been related to point-of-load synchronous buck converters, while fewer, Mariko Shirazi and Dragan Maksimovic Colorado Power Electronics Center ECE Department, University-phase responses, thus simplifying compensator design in wide bandwidth closed-loop voltage regulators based

  15. Practical On-Line Identification of Power Converter Dynamic Responses

    E-Print Network [OSTI]

    parameters to maintain stability at the .. 1 4Switched-Mode Power Converter 1-b I 1 PIIdenfgcation& design-frequency switching power converters has been shown to provide many possible benefits, including improved immunity power convertcrs. These findings provide the first step towards automating the control loop design

  16. Design Considerations for Very High Frequency dc-dc Converters

    E-Print Network [OSTI]

    Perreault, Dave

    the gating power while ensuring fast on- off transitions of the semiconductor switch. The rectifier of switching power converters operating at greatly increased switching frequencies. Greatly increasedDesign Considerations for Very High Frequency dc-dc Converters Juan M. Rivas, David Jackson, Olivia

  17. MATHEMATICAL ANALYSIS OF A WAVE ENERGY CONVERTER ARNAUD ROUGIREL

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    MATHEMATICAL ANALYSIS OF A WAVE ENERGY CONVERTER MODEL ARNAUD ROUGIREL Abstract. In a context where for buoy-type ocean wave energy converter. The simplest model for this scheme is a non autonomous piecewise and periodic solutions, and compare the energy performance of this novel WEC with respect to the one of wave

  18. Multiple Input Converters for Fuel Cells Burak Ozpineci1

    E-Print Network [OSTI]

    Tolbert, Leon M.

    Multiple Input Converters for Fuel Cells Burak Ozpineci1 burak@ieee.org Leon M. Tolbert1,2 tolbert-2100 Abstract-- Multilevel converters have been used previously to integrate several fuel cell modules for higher power applications. Some previous publications have also shown improvements in fuel cell

  19. The New Modular Control System for Power Converters at CERN

    E-Print Network [OSTI]

    Di Cosmo, Matteo

    2015-01-01

    The CERN accelerator complex consists of several generations of particle accelerators, with around 5000 power converters supplying regulated current and voltage to normal and superconducting magnet circuits. Today around 12 generations of converter control platforms can be found in the accelerator complex, ranging in age and technology. The diversity of these platforms has a significant impact on operability, maintenance and support of power converters. Over the past few years a new generation of modular controls called RegFGC3 has been developed by CERN’s power conversion group, with a goal to provide a standardised control platform, supporting a wide variety of converter topologies. The aim of this project is to reduce maintenance costs by decreasing the variety and diversity of control systems whilst simultaneously improving the operability and reliability of power converters and their controls. This paper describes the state of the on-going design and realization of the RegFGC3 platform, focusing on fun...

  20. Magnet Technology for Power Converters: Nanocomposite Magnet Technology for High Frequency MW-Scale Power Converters

    SciTech Connect (OSTI)

    2012-02-27

    Solar ADEPT Project: CMU is developing a new nanoscale magnetic material that will reduce the size, weight, and cost of utility-scale PV solar power conversion systems that connect directly to the grid. Power converters are required to turn the energy that solar power systems create into useable energy for the grid. The power conversion systems made with CMU’s nanoscale magnetic material have the potential to be 150 times lighter and significantly smaller than conventional power conversion systems that produce similar amounts of power.

  1. Free energy of sheared colloidal glasses

    E-Print Network [OSTI]

    M. T. Dang; V. Chikkadi; R. Zargar; D. M. Miedema; D. Bonn; A. Zaccone; P. Schall

    2015-05-25

    We develop a free energy framework to describe the response of glasses to applied stress. Unlike crystals, for which the free energy increases quadratically with strain due to affine displacements, for glasses, the nonequilibrium free energy decreases due to complex interplay of non-affine displacements and dissipation. We measure this free energy directly in strained colloidal glasses, and use mean-field theory to relate it to affine and nonaffine displacements. Nonaffine displacements grow with applied shear due to shear-induced loss of structural connectivity. Our mean-field model allows for the first time to disentangle the complex contributions of affine and nonaffine displacements and dissipation in the transient deformation of glasses.

  2. Direct measurement of shear properties of microfibers

    SciTech Connect (OSTI)

    Behlow, H.; Saini, D.; Durham, L.; Simpson, J.; Skove, M. J.; Rao, A. M. [Department of Physics and Astronomy, and Clemson Nanomaterials Center, Clemson University, Clemson, South Carolina 29634 (United States); Oliveira, L. [School of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634 (United States); Serkiz, S. M. [Department of Physics and Astronomy, and Clemson Nanomaterials Center, Clemson University, Clemson, South Carolina 29634 (United States); Savannah River National Laboratory, Aiken, South Carolina 29808 (United States)

    2014-09-15

    As novel fibers with enhanced mechanical properties continue to be synthesized and developed, the ability to easily and accurately characterize these materials becomes increasingly important. Here we present a design for an inexpensive tabletop instrument to measure shear modulus (G) and other longitudinal shear properties of a micrometer-sized monofilament fiber sample, such as nonlinearities and hysteresis. This automated system applies twist to the sample and measures the resulting torque using a sensitive optical detector that tracks a torsion reference. The accuracy of the instrument was verified by measuring G for high purity copper and tungsten fibers, for which G is well known. Two industrially important fibers, IM7 carbon fiber and Kevlar{sup ®} 119, were also characterized with this system and were found to have G = 16.5 ± 2.1 and 2.42 ± 0.32 GPa, respectively.

  3. Shear viscosity, cavitation and hydrodynamics at LHC

    E-Print Network [OSTI]

    Bhatt, Jitesh R; Sreekanth, V

    2011-01-01

    We study evolution of quark-gluon matter in the ultrarelativistic heavy-ion collisions within the frame work of relativistic second-order viscous hydrodynamics. In particular, by using the various prescriptions of a temperature-dependent shear viscosity to the entropy ratio, we show that the hydrodynamic description of the relativistic fluid become invalid due to the phenomenon of cavitation. For most of the initial conditions relevant for LHC, the cavitation sets in very early during the evolution of the hydrodynamics in time $\\lesssim 2 $fm/c. The cavitation in this case is entirely driven by the large values of shear viscosity. Moreover we also demonstrate that the conformal term used in equations of the relativistic dissipative hydrodynamic can influence the cavitation time.

  4. Shear viscosity, cavitation and hydrodynamics at LHC

    E-Print Network [OSTI]

    Jitesh R. Bhatt; Hiranmaya Mishra; V. Sreekanth

    2011-09-28

    We study evolution of quark-gluon matter in the ultrarelativistic heavy-ion collisions within the frame work of relativistic second-order viscous hydrodynamics. In particular, by using the various prescriptions of a temperature-dependent shear viscosity to the entropy ratio, we show that the hydrodynamic description of the relativistic fluid become invalid due to the phenomenon of cavitation. For most of the initial conditions relevant for LHC, the cavitation sets in very early during the evolution of the hydrodynamics in time $\\lesssim 2 $fm/c. The cavitation in this case is entirely driven by the large values of shear viscosity. Moreover we also demonstrate that the conformal term used in equations of the relativistic dissipative hydrodynamic can influence the cavitation time.

  5. Flocculation of model algae under shear.

    SciTech Connect (OSTI)

    Pierce, Flint; Lechman, Jeremy B.

    2010-11-01

    We present results of molecular dynamics simulations of the flocculation of model algae particles under shear. We study the evolution of the cluster size distribution as well as the steady-state distribution as a function of shear rates and algae interaction parameters. Algal interactions are modeled through a DLVO-type potential, a combination of a HS colloid potential (Everaers) and a yukawa/colloid electrostatic potential. The effect of hydrodynamic interactions on aggregation is explored. Cluster strucuture is determined from the algae-algae radial distribution function as well as the structure factor. DLVO parameters including size, salt concentration, surface potential, initial volume fraction, etc. are varied to model different species of algae under a variety of environmental conditions.

  6. Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted

    E-Print Network [OSTI]

    Massachusetts at Amherst, University of

    Wind turbines convert the kinetic energy in moving air into rotational energy, which in turn is converted to electricity. Since wind speeds vary from month to month and second to second, the amount of electricity wind can make varies constantly. Sometimes a wind turbine will make no power at all

  7. Shear flow pumping in open microfluidic systems

    E-Print Network [OSTI]

    Markus Rauscher; S. Dietrich; Joel Koplik

    2006-10-26

    We propose to drive open microfluidic systems by shear in a covering fluid layer, e.g., oil covering water-filled chemical channels. The advantages as compared to other means of pumping are simpler forcing and prevention of evaporation of volatile components. We calculate the expected throughput for straight channels and show that devices can be built with off-the-shelf technology. Molecular dynamics simulations suggest that this concept is scalable down to the nanoscale.

  8. Amorphous Systems in Athermal, Quasistatic Shear

    E-Print Network [OSTI]

    Craig E. Maloney; Anaël Lemaître

    2005-10-28

    We present results on a series of 2D atomistic computer simulations of amorphous systems subjected to simple shear in the athermal, quasistatic limit. The athermal quasistatic trajectories are shown to separate into smooth, reversible elastic branches which are intermittently broken by discrete catastrophic plastic events. The onset of a typical plastic event is studied with precision, and it is shown that the mode of the system which is responsible for the loss of stability has structure in real space which is consistent with a quadrupolar source acting on an elastic matrix. The plastic events themselves are shown to be composed of localized shear transformations which organize into lines of slip which span the length of the simulation cell, and a mechanism for the organization is discussed. Although within a single event there are strong spatial correlations in the deformation, we find little correlation from one event to the next, and these transient lines of slip are not to be confounded with the persistent regions of localized shear -- so-called "shear bands" -- found in related studies. The slip lines gives rise to particular scalings with system length of various measures of event size. Strikingly, data obtained using three differing interaction potentials can be brought into quantitative agreement after a simple rescaling, emphasizing the insensitivity of the emergent plastic behavior in these disordered systems to the precise details of the underlying interactions. The results should be relevant to understanding plastic deformation in systems such as metallic glasses well below their glass temperature, soft glassy systems (such as dense emulsions), or compressed granular materials.

  9. Microphase transitions of block copolymer/homopolymer under shear flow

    E-Print Network [OSTI]

    Y. Guo; J. Zhang; B. Wang; H. Wu; M. Sun; J. Pan

    2015-06-26

    Cell dynamics simulation is used to investigate the phase behavior of block copolymer/homopolymer mixture subjected to a steady shear flow. Phase transitions occur from transverse to parallel and then to perpendicular lamellar structure with an increase of shear rate and this is the result of interaction between the shear flow and the concentration fluctuation. Rheological properties, such as normal stress differences and shear viscosity, are all closely related with the direction of the lamellae. Furthermore, we specifically explore the phase behavior and the order parameter under weak and strong shear of two different initial states, and realize the importance of the thermal history. It is necessary to apply the shear field at the appropriate time if we want to get what we want. These results provide an easy method to create ordered, defect-free materials in experiment and engineering technology through imposing shear flow.

  10. Tensile & shear strength of porous dust agglomerates

    E-Print Network [OSTI]

    Alexander Seizinger; Roland Speith; Wilhelm Kley

    2013-08-23

    Context.Within the sequential accretion scenario of planet formation, planets are build up through a sequence sticking collisions. The outcome of collisions between porous dust aggregates is very important for the growth from very small dust particles to planetesimals. In this work we determine the necessary material properties of dust aggregates as a function the porosity. Aims: Continuum models such as SPH that are capable of simulating collisions of macroscopic dust aggregates require a set of material parameters. Some of them such as the tensile and shear strength are ?difficult to obtain from laboratory experiments. The aim of this work is to determine these parameters from ab-initio molecular dynamics simulations. Methods: We simulate the behavior of porous dust aggregates using a detailed micro-physical model of the interaction of spherical grains that includes adhesion forces, rolling, twisting, and sliding. Using different methods of preparing the samples we study the strength behavior of our samples with varying porosity and coordination number of the material. Results: For the tensile strength, we can reproduce data from laboratory experiments very well. For the shear strength, there are no experimental data available. The results from our simulations differ significantly from previous theoretical models, which indicates that the latter might not be sufficient to describe porous dust aggregates. Conclusions: We have provided functional behavior of tensile and shear strength of porous dust aggregates as a function of the porosity that can be directly applied in continuum simulations of these objects in planet formation scenarios.

  11. Direct Numerical Simulation of Surfactant-Stabilized Emulsions Morphology and Shear Viscosity in Starting Shear Flow

    SciTech Connect (OSTI)

    Roar Skartlien; Espen Sollum; Andreas Akselsen; Paul Meakin

    2012-07-01

    A 3D lattice Boltzmann model for two-phase flow with amphiphilic surfactant was used to investigate the evolution of emulsion morphology and shear stress in starting shear flow. The interfacial contributions were analyzed for low and high volume fractions and varying surfactant activity. A transient viscoelastic contribution to the emulsion rheology under constant strain rate conditions was attributed to the interfacial stress. For droplet volume fractions below 0.3 and an average capillary number of about 0.25, highly elliptical droplets formed. Consistent with affine deformation models, gradual elongation of the droplets increased the shear stress at early times and reduced it at later times. Lower interfacial tension with increased surfactant activity counterbalanced the effect of increased interfacial area, and the net shear stress did not change significantly. For higher volume fractions, co-continuous phases with a complex topology were formed. The surfactant decreased the interfacial shear stress due mainly to advection of surfactant to higher curvature areas. Our results are in qualitative agreement with experimental data for polymer blends in terms of transient interfacial stresses and limited enhancement of the emulsion viscosity at larger volume fractions where the phases are co-continuous.

  12. Generating Isolated Outputs in a Multilevel Modular Capacitor Clamped DC-DC Converter

    E-Print Network [OSTI]

    Tolbert, Leon M.

    -dc converters based on inductive energy transfer method (IETM) such as buck, boost, and buck-boost converter967 Generating Isolated Outputs in a Multilevel Modular Capacitor Clamped DC-DC Converter (MMCCC clamped dc-dc converter. The multilevel modular capacitor clamped converter (MMCCC) has several key

  13. Bifurcation in a System of Coupled Buck Converters Herbert H. C. Iu

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    electronic regulators (e.g. buck converter, boost converter and buck-boost converter) have been thoroughlyBifurcation in a System of Coupled Buck Converters Herbert H. C. Iu , Chi K. Tse and Octavian the bifurcation behaviour of a system of coupled buck converters under current-mode control. The effects due

  14. Modeling and Analysis of Hybrid Converters Michael Evzelman Shmuel (Sam) Ben-Yaakov

    E-Print Network [OSTI]

    by simulation and experimentally. The experimental converter included a Boost converter followed by x3 switched. This can be conveniently done by hybrid converters with multiple Figure 1. Hybrid Boost SCCx3 converterModeling and Analysis of Hybrid Converters Michael Evzelman Shmuel (Sam) Ben-Yaakov Power

  15. Bifurcation in Parallel-Connected Buck Converters under Current-Mode Control

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    converter, boost converter and buck-boost converter) have been thoroughly studied in the past decade [1], [2Bifurcation in Parallel-Connected Buck Converters under Current-Mode Control H. H. C. Iu School a system of parallel-connected dc/dc buck converters under current-mode control. The effects of variations

  16. CFRP SHEAR STRENGTHENING OF REINFORCED CONCRETE T-BEAMS WITH CORRODED SHEAR LINKS

    E-Print Network [OSTI]

    Qin, Shunde; Dirar, Samir; Yang, Jian; Chan, Andrew H. C.; Elshafie, Mohammed

    2014-12-17

    better bond 57 performance between the concrete and the FRP reinforcement (Chaallal et al., 2011). 58 A careful review of the published literature reveals that research studies investigating the 59 shear behavior of RC beams strengthened using the DE... of reinforced concrete 500 beams strengthened in shear using L-shaped CFRP plates: experimental investigation.” J. 501 Compos. Constr., 10.1061/(ASCE)CC.1943-5614.0000398, 04013033. 502 503 Rahal, K. N., and Rumaih, H. A. (2011). “Tests on reinforced concrete...

  17. Protocols for the Equitable Assessment of Marine Energy Converters 

    E-Print Network [OSTI]

    Ingram, David; Smith, George; Bittencourt-Ferreira, Claudio; Smith, Helen

    This book contains the suite of protocols for the equitable evaluation of marine energy converters (based on either tidal or wave energy) produced by the EquiMar consortium led by the University of Edinburgh. These protocols ...

  18. Oversampled pipline A/D converters with mismatch shaping

    E-Print Network [OSTI]

    Shabra, Ayman U. (Ayman Umar)

    2001-01-01

    This thesis introduces a technique to improve the linearity of pipeline analog to digital converters (ADC). Through a combination of oversampling and mismatch shaping, the distortion introduced by component mismatch is ...

  19. Design Methodology for a Very High Frequency Resonant Boost Converter

    E-Print Network [OSTI]

    Burkhart, Justin M.

    This paper introduces a design methodology for a resonant boost converter topology that is suitable for operation at very high frequencies. The topology we examine features a low parts count and fast transient response, ...

  20. Design methodology for a very high frequency resonant boost converter

    E-Print Network [OSTI]

    Burkhart, Justin M.

    This document introduces a design methodology for a resonant boost converter topology that is suitable for operation at very high frequencies. The topology we examine features a low parts count and fast transient response ...

  1. Development, evaluation, and design applications of an AMTEC converter model 

    E-Print Network [OSTI]

    Spence, Cliff Alan

    2002-01-01

    An AMTEC converter model was developed and its effectiveness as a design tool was evaluated. To develop the model, requirements of the model were defined, modeling equations were selected, and a methodology for model development was established...

  2. Soft switched high frequency ac-link converter 

    E-Print Network [OSTI]

    Balakrishnan, Anand Kumar

    2009-05-15

    Variable frequency drives typically have employed dc voltage or current links for power distribution between the input and output converters and as a means to temporarily store energy. The dc link based power conversion systems have several inherent...

  3. Method for converting uranium oxides to uranium metal

    DOE Patents [OSTI]

    Duerksen, Walter K. (Norris, TN)

    1988-01-01

    A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.

  4. Converting normal insulators into topological insulators via tuning orbital levels

    E-Print Network [OSTI]

    Shi, Wu-Jun

    Tuning the spin-orbit coupling strength via foreign element doping and modifying bonding strength via strain engineering are the major routes to convert normal insulators to topological insulators. We here propose an ...

  5. Non-synchronous control of self-oscillating resonant converters

    DOE Patents [OSTI]

    Glaser, John Stanley (Niskayuna, NY); Zane, Regan Andrew (Scotia, NY)

    2002-01-01

    A self-oscillating switching power converter has a controllable reactance including an active device connected to a reactive element, wherein the effective reactance of the reactance and the active device is controlled such that the control waveform for the active device is binary digital and is not synchronized with the switching converter output frequency. The active device is turned completely on and off at a frequency that is substantially greater than the maximum frequency imposed on the output terminals of the active device. The effect is to vary the average resistance across the active device output terminals, and thus the effective output reactance, thereby providing converter output control, while maintaining the response speed of the converter.

  6. A Dual Supply Buck Converter with Improved Light Load Efficiency 

    E-Print Network [OSTI]

    Chen, Hui

    2013-05-02

    Power consumption is the primary concern in battery-operated portable applications. Buck converters have gained popularity in powering portable devices due to their compact size, good current delivery capability and high efficiency. However...

  7. Vehicle Technologies Office Merit Review 2014: WBG Converters and Chargers

    Broader source: Energy.gov [DOE]

    Presentation given by Oak Ridge National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about WBG converters...

  8. Dynamics of flexible fibers in shear flow

    E-Print Network [OSTI]

    Agnieszka M. Slowicka; Eligiusz Wajnryb; Maria L. Ekiel-Jezewska

    2015-04-03

    Dynamics of flexible non-Brownian fibers in shear flow at low-Reynolds-number are analyzed numerically for a wide range of the ratios A of the fiber bending force to the viscous drag force. Initially, the fibers are aligned with the flow, and later they move in the plane perpendicular to the flow vorticity. A surprisingly rich spectrum of different modes is observed when the value of A is systematically changed, with sharp transitions between coiled and straightening out modes, period-doubling bifurcations from periodic to migrating solutions, irregular dynamics and chaos.

  9. Critical shear stresses in cohesive soils 

    E-Print Network [OSTI]

    Rektorik, Robert James

    1964-01-01

    provided by Dr. E. T. Smerdon l during the course of this study and also to express my appreciation to Mr. J. W. Sorenson, Mr. R. E. Schiller, Jr. , and Dr. 7. D. Williams for the assistance provided in the preparation of this report. I also wish... . where 11 w = angular velocity 2 M = 2n (R ) ht = torque on the inner cylinder 1 h = height of the inner cylinder dynamic viscosity R = radius of inner cylinder 1 R = radius of inner face of the outer cylinder 2 t = boundary shear FL FTL FL...

  10. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, N.R.; King, R.D.; Schwartz, J.E.

    1999-05-11

    A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals. 10 figs.

  11. Bi-directional power control system for voltage converter

    DOE Patents [OSTI]

    Garrigan, Neil Richard (Niskayuna, NY); King, Robert Dean (Schenectady, NY); Schwartz, James Edward (Slingerlands, NY)

    1999-01-01

    A control system for a voltage converter includes: a power comparator for comparing a power signal on input terminals of the converter with a commanded power signal and producing a power comparison signal; a power regulator for transforming the power comparison signal to a commanded current signal; a current comparator for comparing the commanded current signal with a measured current signal on output terminals of the converter and producing a current comparison signal; a current regulator for transforming the current comparison signal to a pulse width modulator (PWM) duty cycle command signal; and a PWM for using the PWM duty cycle command signal to control electrical switches of the converter. The control system may further include: a command multiplier for converting a voltage signal across the output terminals of the converter to a gain signal having a value between zero (0) and unity (1), and a power multiplier for multiplying the commanded power signal by the gain signal to provide a limited commanded power signal, wherein power comparator compares the limited commanded power signal with the power signal on the input terminals.

  12. An evaluation of a parallel-resonant current-source converter for an electrothermal thruster 

    E-Print Network [OSTI]

    Tchamdjou, Aristide-Marie

    1996-01-01

    The Parallel-Resonant Current-Source Converter promises highly efficient DCDC power conversion. It uses zero-voltage switching to reduce the losses and improve the converter efficiency. The Parallel-Resonant Current-Source Converter has been...

  13. Mass-modulation schemes for a class of wave energy converters: Experiments, models, and efficacy

    E-Print Network [OSTI]

    Diamond, CA; Judge, CQ; Orazov, B; Sava?, Ö; O'Reilly, OM

    2015-01-01

    dynamics of a novel ocean wave energy converter. Journal of5565. Dick, W. , 2005. Wave energy converter. U.S. Patentof the IPS buoy wave energy converter including the effect

  14. A New Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Physical Parameters

    E-Print Network [OSTI]

    Victoria, University of

    A New Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Methodology for Frequency Domain Analysis of Wave Energy Converters with Periodically Varying Physical of Mechanical Engineering) ABSTRACT Within a wave energy converter's operational bandwidth, device operation

  15. BEHAVIOUR OF PRECAST CONCRETE SHEAR WALL CONNECTIONS UNDER LARGE REVERSED CYCLIC SHEAR LOADS

    E-Print Network [OSTI]

    shear wall panels are an economical construction system for low, medium and high rise structures.S. West K.A. Soudki S.H. RizkaIla Structural Engineering and Construction Research and Development of high quality precast elements in a controlled factory environment and rapid cost-effective erection

  16. Aerosol penetration through a seismically loaded shear wall

    SciTech Connect (OSTI)

    Farrar, C.R.; Girrens, S.P.

    1992-05-01

    An experimental study was performed to measure the aerosol penetration through a reinforced concrete shear wall after simulated seismic damage. Static load-cycle testing, to stress levels sufficient to induce visible shear cracking, was used to simulate the earthquake loading. Air permeability tests were performed both before and after the simulated seismic loading damaged the structure. Aerosol penetration measurements were conducted on the cracked shear wall structure using 0.10 {mu}m monodisperse particles. The measured aerosol number penetration through the cracked shear wall was 0.5%. 7 refs.

  17. Aerosol penetration through a seismically loaded shear wall

    SciTech Connect (OSTI)

    Farrar, C.R.; Girrens, S.P.

    1992-01-01

    An experimental study was performed to measure the aerosol penetration through a reinforced concrete shear wall after simulated seismic damage. Static load-cycle testing, to stress levels sufficient to induce visible shear cracking, was used to simulate the earthquake loading. Air permeability tests were performed both before and after the simulated seismic loading damaged the structure. Aerosol penetration measurements were conducted on the cracked shear wall structure using 0.10 {mu}m monodisperse particles. The measured aerosol number penetration through the cracked shear wall was 0.5%. 7 refs.

  18. Shear thickening in electrically stabilized non-aqueous colloidal suspensions

    E-Print Network [OSTI]

    Joachim Kaldasch; Bernhard Senge; Jozua Laven

    2012-07-11

    The authors previously introduced an activation model for the onset of shear thickening in electrically stabilized colloidal suspensions. It predicts that shear thickening occurs, when particles arranged along the compression axis in a sheared suspension do overcome the electrostatic repulsion at a critical shear stress, and are captured in the primary minimum of the DLVO interaction potential. A comparison with an experimental investigation on non-aqueous silica suspensions, carried out by Maranzano and Wagner, is performed. For particle systems that fall into the applicability range of the theory, a good coincidence between the experimental data and the model predictions can be found.

  19. Modeling shear failure and permeability enhancement due to coupled...

    Office of Scientific and Technical Information (OSTI)

    enhancement due to coupled Thermal-Hydrological-Mechanical processes in Enhanced Geothermal Reservoirs Citation Details In-Document Search Title: Modeling shear failure and...

  20. Shear Viscosity Coefficient from Microscopic Models

    E-Print Network [OSTI]

    Azwinndini Muronga

    2003-12-02

    The transport coefficient of shear viscosity is studied for a hadron matter through microscopic transport model, the Ultra--relativistic Quantum Molecular Dynamics (UrQMD), using the Green--Kubo formulas. Molecular--dynamical simulations are performed for a system of light mesons in a box with periodic boundary conditions. Starting from an initial state composed of $\\pi, \\eta ,\\omega ,\\rho ,\\phi$ with a uniform phase--space distribution, the evolution takes place through elastic collisions, production and annihilation. The system approaches a stationary state of mesons and their resonances, which is characterized by common temperature. After equilibration, thermodynamic quantities such as the energy density, particle density, and pressure are calculated. From such an equilibrated state the shear viscosity coefficient is calculated from the fluctuations of stress tensor around equilibrium using Green--Kubo relations. We do our simulations here at zero net baryon density so that the equilibration times depend on the energy density. We do not include hadron strings as degrees of freedom so as to maintain detailed balance. Hence we do not get the saturation of temperature but this leads to longer equilibration times.

  1. Dual-domain lateral shearing interferometer

    DOE Patents [OSTI]

    Naulleau, Patrick P.; Goldberg, Kenneth Alan

    2004-03-16

    The phase-shifting point diffraction interferometer (PS/PDI) was developed to address the problem of at-wavelength metrology of extreme ultraviolet (EUV) optical systems. Although extremely accurate, the fact that the PS/PDI is limited to use with coherent EUV sources, such as undulator radiation, is a drawback for its widespread use. An alternative to the PS/PDI, with relaxed coherence requirements, is lateral shearing interferometry (LSI). The use of a cross-grating, carrier-frequency configuration to characterize a large-field 4.times.-reduction EUV lithography optic is demonstrated. The results obtained are directly compared with PS/PDI measurements. A defocused implementation of the lateral shearing interferometer in which an image-plane filter allows both phase-shifting and Fourier wavefront recovery. The two wavefront recovery methods can be combined in a dual-domain technique providing suppression of noise added by self-interference of high-frequency components in the test-optic wavefront.

  2. DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary...

    Office of Environmental Management (EM)

    8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards DOE-TSPP-8-2013, Converting DOE Technical Standards to Voluntary Consensus Standards Technical Standards...

  3. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    A review of wave energy converter technology. Proceedings ofdecades. With the technology of wave-energy convert- ers(Wave energy utilization: A review of the technologies. Re-

  4. Probing CP Violation in $h\\rightarrow\\gamma\\gamma$ with Converted...

    Office of Scientific and Technical Information (OSTI)

    CP Violation in hrightarrowgammagamma with Converted Photons Citation Details In-Document Search Title: Probing CP Violation in hrightarrowgammagamma with Converted...

  5. Sub-picosecond Resolution Time-to-Digital Converter

    SciTech Connect (OSTI)

    Ph D, Vladimir Bratov; Ph D, Vladimir Katzman; MS EE, Jeb Binkley

    2006-03-30

    Time-to-digital converters with sub-picosecond resolutions are needed to satisfy the requirements of time-on-flight measurements of the next generation of high energy and nuclear physics experiments. The converters must be highly integrated, power effective, low cost, and feature plug-and-play capabilities to handle the increasing number of channels (up to hundreds of millions) in future Department of Energy experiments. Current state-off-the-art time-to-digital converter integrated circuits do not have the sufficient degree of integration and flexibility to fulfill all the described requirements. During Phase I, the Advanced Science and Novel Technology Company in cooperation with the nuclear physics division of the Oak Ridge National Laboratory has developed the architecture of a novel time-to-digital converter with multiple channels connected to an external processor through a special interfacing block and synchronized by clock signals generated by an internal phase-locked loop. The critical blocks of the system including signal delay lines and delay-locked loops with proprietary differential delay cells, as well as the required digital code converter and the clock period counter have been designed and simulated using the advanced SiGe120 BiCMOS technological process. The results of investigations demonstrate a possibility to achieve the digitization accuracy within 1ps. ADSANTEC has demonstrated the feasibility of the proposed concept in computer simulations. The proposed system will be a critical component for the next generation of NEP experiments.

  6. Acoustic Modes in a Ducted Shear Flow Gregory Vilenski

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Acoustic Modes in a Ducted Shear Flow Gregory Vilenski Sjoerd W. Rienstra Eindhoven University but sheared mean flow inside a duct is considered. For isentropic flow in a circular duct with zero swirl = dimensional inner duct radius d = dimensional outer duct radius = dimensional frequency m = circumferential

  7. Reinterpretation of the RRISP-77 Iceland Shear Wave Profiles

    E-Print Network [OSTI]

    Menke, William

    Reinterpretation of the RRISP-77 Iceland Shear Wave Profiles William Menke , Bryndís Brandsdóttir Sciences of Columbia University, Palisades NY 10964 USA £ Science Institute, University of Iceland Dunhagi 5, Reykjavík IS-107 Iceland SUMMARY Two shear wave profiles, E and G, collected during the 1977

  8. Reinterpretation of the RRISP77 Iceland Shear Wave Profiles

    E-Print Network [OSTI]

    Menke, William

    Reinterpretation of the RRISP­77 Iceland Shear Wave Profiles William Menke 1 , Bryndís Brandsdóttir. of Geological Sciences of Columbia University, Palisades NY 10964 USA 2 Science Institute, University of Iceland Dunhagi 5, Reykjavík IS­107 Iceland SUMMARY Two shear wave profiles, E and G, collected during the 1977

  9. Large Deformation of Nitinol Under Shear Dominant Loading

    E-Print Network [OSTI]

    Bhattacharya, Kaushik

    Large Deformation of Nitinol Under Shear Dominant Loading S. Daly & D. Rittel & K. Bhattacharya & G Abstract Full-field quantitative strain maps of phase transformation and plasticity in Nitinol under large that is seen in uniaxial testing. The shear-dominant deformation of Nitinol in the plastic regime exhibits low

  10. ORIGINAL PAPER Shear Wave Splitting and Mantle Anisotropy

    E-Print Network [OSTI]

    ORIGINAL PAPER Shear Wave Splitting and Mantle Anisotropy: Measurements, Interpretations, and New to make and interpret splitting measurements correctly and how to relate them properly to mantle flow and recent developments in the measurement and interpretation of shear wave splitting--including new

  11. Sequential Bifurcations in Sheared Annular Electroconvection

    E-Print Network [OSTI]

    Zahir A. Daya; V. B. Deyirmenjian; Stephen W. Morris

    2001-11-02

    A sequence of bifurcations is studied in a one-dimensional pattern forming system subject to the variation of two experimental control parameters: a dimensionless electrical forcing number ${\\cal R}$ and a shear Reynolds number ${\\rm Re}$. The pattern is an azimuthally periodic array of traveling vortices with integer mode number $m$. Varying ${\\cal R}$ and ${\\rm Re}$ permits the passage through several codimension-two points. We find that the coefficients of the nonlinear terms in a generic Landau equation for the primary bifurcation are discontinuous at the codimension-two points. Further, we map the stability boundaries in the space of the two parameters by studying the subcritical secondary bifurcations in which $m \\to m+1$ when ${\\cal R}$ is increased at constant ${\\rm Re}$.

  12. Adjustable shear stress erosion and transport flume

    DOE Patents [OSTI]

    Roberts, Jesse D. (Carlsbad, NM); Jepsen, Richard A. (Carlsbad, NM)

    2002-01-01

    A method and apparatus for measuring the total erosion rate and downstream transport of suspended and bedload sediments using an adjustable shear stress erosion and transport (ASSET) flume with a variable-depth sediment core sample. Water is forced past a variable-depth sediment core sample in a closed channel, eroding sediments, and introducing suspended and bedload sediments into the flow stream. The core sample is continuously pushed into the flow stream, while keeping the surface level with the bottom of the channel. Eroded bedload sediments are transported downstream and then gravitationally separated from the flow stream into one or more quiescent traps. The captured bedload sediments (particles and aggregates) are weighed and compared to the total mass of sediment eroded, and also to the concentration of sediments suspended in the flow stream.

  13. Statement of Interest in a New Project, in response to PPARC call of April 26th FHIRN: A next-generation radio network for exploring the 3-dimensional solar wind

    E-Print Network [OSTI]

    spacecraft will build on these successes, with the Japan-UK Solar-B and NASA Solar Dynamics Observatory (SDO-generation radio network for exploring the 3-dimensional solar wind Future Heliospheric Imaging Radio Network The solar wind is a supersonically-expanding extension of the solar atmosphere into interplanetary space

  14. Methods for degrading or converting plant cell wall polysaccharides

    DOE Patents [OSTI]

    Berka, Randy (Davis, CA); Cherry, Joel (Davis, CA)

    2008-08-19

    The present invention relates to methods for converting plant cell wall polysaccharides into one or more products, comprising: treating the plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into the one or more products. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into saccharified material; (b) fermenting the saccharified material of step (a) with one or more fermenting microoganisms; and (c) recovering the organic substance from the fermentation.

  15. Power line carrier interference from HVDC converter terminals

    SciTech Connect (OSTI)

    Tatro, P.J.; Adamson, K.A. (New England Power Service Co., Westborough, MA (United States)); Eitzmann, M.A.; Smead, M. (GE Industrial and Power Systems, Schenectady, NY (United States). Power Systems Engineering Dept.)

    1993-07-01

    Power line carrier (PLC) equipment typically operates in the frequency range from 25 kHz to 300 kHz. Interference studies for HVDC converters usually concentrate on interference from noise sources within this frequency range. However, operating experience at the Sandy Pond converter terminal has indicated that PLC equipment is also susceptible to interference from sources of power system harmonics below the PLC frequency range. Extensive field testing and analytical studies have shown that each PLC circuit has a resonant frequency below the operating frequency. If excited at this resonant frequency, high voltages may exist within the PLC circuit. The resulting saturation of PLC components leads to local generation of radio frequency (RF) noise that interferes with proper operation of PLC circuits. Sources of power system harmonics in the 3-10 kHz range, such as line commutated dc converters, are potential sources of this type of interference.

  16. Auxiliary quasi-resonant dc tank electrical power converter

    DOE Patents [OSTI]

    Peng, Fang Z.

    2006-10-24

    An auxiliary quasi-resonant dc tank (AQRDCT) power converter with fast current charging, voltage balancing (or charging), and voltage clamping circuits is provided for achieving soft-switched power conversion. The present invention is an improvement of the invention taught in U.S. Pat. No. 6,111,770, herein incorporated by reference. The present invention provides faster current charging to the resonant inductor, thus minimizing delay time of the pulse width modulation (PWM) due to the soft-switching process. The new AQRDCT converter includes three tank capacitors or power supplies to achieve the faster current charging and minimize the soft-switching time delay. The new AQRDCT converter further includes a voltage balancing circuit to charge and discharge the three tank capacitors so that additional isolated power supplies from the utility line are not needed. A voltage clamping circuit is also included for clamping voltage surge due to the reverse recovery of diodes.

  17. Density waves in the shearing sheet I. Swing amplification

    E-Print Network [OSTI]

    B. Fuchs

    2001-03-02

    The shearing sheet model of a galactic disk is studied anew. The theoretical description of its dynamics is based on three building blocks: Stellar orbits, which are described here in epicyclic approximation, the collisionless Boltzmann equation determining the distribution function of stars in phase space, and the Poisson equation in order to take account of the self-gravity of the disk. Using these tools I develop a new formalism to describe perturbations of the shearing sheet. Applying this to the unbounded shearing sheet model I demonstrate again how the disturbances of the disk evolve always into `swing amplified' density waves, i.e. spiral-arm like, shearing density enhancements, which grow and decay while the wave crests swing by from leading to trailing orientation. Several examples are given how such `swing amplification' events are incited in the shearing sheet.

  18. Crystallization Kinetics of Colloidal Spheres under Stationary Shear Flow

    E-Print Network [OSTI]

    P. Holmqvist; M. P. Lettinga; J. Buitenhuis; J. K. G. Dhont

    2005-08-29

    A systematic experimental study of dispersions of charged colloidal spheres is presented on the effect of steady shear flow on nucleation and crystal-growth rates. In addition, the non-equilibrium phase diagram as far as the melting line is concerned is measured. Shear flow is found to strongly affect induction times, crystal growth rates and the location of the melting line. The main findings are that (i) the crystal growth rate for a given concentration exhibits a maximum as a function of the shear rate, (ii) contrary to the monotonous increase of the growth rate with increasing concentration in the absence of flow, a maximum of the crystal growth rate as a function of concentration is observed for sheared systems, and (iii) the induction time for a given concentration exhibits a maximum as a function of the shear rate. These findings will be partly explained on a qualitative level.

  19. ASYMPTOTIC AND COMPUTATIONAL ANALYSIS OF LARGE SHEAR DEFORMATIONS OF A THERMOPLASTIC MATERIAL

    E-Print Network [OSTI]

    Edwards, David A.

    ASYMPTOTIC AND COMPUTATIONAL ANALYSIS OF LARGE SHEAR DEFORMATIONS OF A THERMOPLASTIC MATERIAL D. A, asymptotics, finite differences, shear bands, singular perturbations, thermoplastic materials AMS subject of high strain that develop in materials under intense thermoplastic shear deformations. Since they often

  20. Lake-size dependency of wind shear and convection as controls on gas exchange

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Lake-size dependency of wind shear and convection as controls on gas exchange Jordan S. Read,1 the relative contributions of wind shear (u*) and convection (w*) to turbulence in the surface mixed layer wind shear (u*/w*

  1. Process for converting cellulosic materials into fuels and chemicals

    DOE Patents [OSTI]

    Scott, Charles D. (Oak Ridge, TN); Faison, Brendlyn D. (Knoxville, TN); Davison, Brian H. (Knoxville, TN); Woodward, Jonathan (Oak Ridge, TN)

    1994-01-01

    A process for converting cellulosic materials, such as waste paper, into fuels and chemicals utilizing enzymatic hydrolysis of the major constituent of paper, cellulose. A waste paper slurry is contacted by cellulase in an agitated hydrolyzer. The cellulase is produced from a continuous, columnar, fluidized-bed bioreactor utilizing immobilized microorganisms. An attritor and a cellobiase reactor are coupled to the agitated hydrolyzer to improve reaction efficiency. The cellulase is recycled by an adsorption process. The resulting crude sugars are converted to dilute product in a fluidized-bed bioreactor utilizing microorganisms. The dilute product is concentrated and purified by utilizing distillation and/or a biparticle fluidized-bed bioreactor system.

  2. Method for converting sucrose to .beta.-D-glucose

    DOE Patents [OSTI]

    Simmons, Blake A. (San Francisco, CA); Volponi, Joanne V. (Livermore, CA); Ingersoll, David (Albuquerque, NM); Walker, Andrew (Woodinville, WA)

    2009-07-07

    Disclosed is an apparatus and method for continuously converting sucrose to .beta.-D-glucose. The method comprises a three-stage enzymatic reactor in which an aqueous solution of sucrose is first converted into a solution of fructose and .alpha.-D-glucose by passing it through a porous, packed column containing an inert media on which invertase is immobilized. This solution is then sent through a second packed column containing glucose isomerase and finally a third packed column containing mutarotase. Solution temperature and pH are adjusted to maximize glucose output.

  3. Influence of inherent structure shear stress of supercooled liquids on their shear moduli

    E-Print Network [OSTI]

    Ingo Fuereder; Patrick Ilg

    2015-04-13

    Configurations of supercooled liquids residing in their local potential minimum (i.e. in their inherent structure, IS) were found to support a non-zero shear stress. This IS stress was attributed to the constraint to the energy minimization imposed by boundary conditions, which keep size and shape of the simulation cell fixed. In this paper we further investigate the influence of these boundary conditions on the IS stress. We investigate its importance for the computation of the low frequency shear modulus of a glass obtaining a consistent picture for the low- and high frequency shear moduli over the full temperature range. Hence, we find that the IS stress corresponds to a non-thermal contribution to the fluctuation term in the Born-Green expression. This leads to an unphysical divergence of the moduli in the low temperature limit if no proper correction for this term is applied. Furthermore, we clarify the IS stress dependence on the system size and put its origin on a more formal basis.

  4. Northwest Energy Innovations (TRL 5 6 System)- WETNZ MtiMode Wave Energy Converter Advancement Project

    Broader source: Energy.gov [DOE]

    Northwest Energy Innovations (TRL 5 6 System) - WETNZ MtiMode Wave Energy Converter Advancement Project

  5. Analysis and Optimization of Switched-Capacitor DC-DC Converters

    E-Print Network [OSTI]

    Sanders, Seth

    on conduction loss) of a ladder-type converter is found to be superior to that of a conventional boost converterAnalysis and Optimization of Switched-Capacitor DC-DC Converters Michael D. Seeman, Seth R. Sanders­ Analysis methods are developed that fully determine a switched-capacitor (SC) dc-dc converter's steady

  6. IEEE TRANSACTIONS ON POWER ELECTRONICS 1 Singular Perturbation Theory for DCDC Converters

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    model. Similar results hold for boost, buck, and buck­boost converters. Experimental boost convertersIEEE TRANSACTIONS ON POWER ELECTRONICS 1 Singular Perturbation Theory for DC­DC Converters and Application to PFC Converters Jonathan W. Kimball, Senior Member, IEEE, and Philip T. Krein, Fellow, IEEE

  7. 17.March.2005 C. A. Martins, CERN AB/PO 1 Power converter

    E-Print Network [OSTI]

    McDonald, Kirk

    , 1000Vdc Converter topology 18 kV cell Power transformers (in an oil tank) 2x4 Rectifier bridges Passive Passive filter self Passive filter capacitors self capacitors DC output #12;17.March.2005 C. A. Martins Converters location: · At building 193 (AD) like ALICE/LHCb converter 2nd choice target Power converter (193

  8. Sigma-Delta Modulation of Multi-Phase High Frequency Converters

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    Sigma-Delta Modulation of Multi-Phase High Frequency Converters Jonathan W. Kimball, Senior Member control architecture is proposed that merges advanced digital modulation techniques, high frequency resonant converters, and multi-phase converters. If a converter's switching frequency is high enough

  9. Two-Year and Lifetime Cost-Effectiveness of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Head-and-Neck Cancer

    SciTech Connect (OSTI)

    Kohler, Racquel E. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Sheets, Nathan C. [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States); Wheeler, Stephanie B. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Nutting, Chris [Royal Marsden Hospital, London, United Kindom (United Kingdom); Hall, Emma [Clinical Trials and Statistics Unit, Division of Clinical Studies, Institute of Cancer Research, London (United Kingdom); Chera, Bhishamjit S., E-mail: bchera@med.unc.edu [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States)

    2013-11-15

    Purpose: To assess the cost-effectiveness of intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) in the treatment of head-and neck-cancer (HNC). Methods and Materials: We used a Markov model to simulate radiation therapy-induced xerostomia and dysphagia in a hypothetical cohort of 65-year-old HNC patients. Model input parameters were derived from PARSPORT (CRUK/03/005) patient-level trial data and quality-of-life and Medicare cost data from published literature. We calculated average incremental cost-effectiveness ratios (ICERs) from the US health care perspective as cost per quality-adjusted life-year (QALY) gained and compared our ICERs with current cost-effectiveness standards whereby treatment comparators less than $50,000 per QALY gained are considered cost-effective. Results: In the first 2 years after initial treatment, IMRT is not cost-effective compared with 3D-CRT, given an average ICER of $101,100 per QALY gained. However, over 15 years (remaining lifetime on the basis of average life expectancy of a 65-year-old), IMRT is more cost-effective at $34,523 per QALY gained. Conclusion: Although HNC patients receiving IMRT will likely experience reduced xerostomia and dysphagia symptoms, the small quality-of-life benefit associated with IMRT is not cost-effective in the short term but may be cost-effective over a patient's lifetime, assuming benefits persist over time and patients are healthy and likely to live for a sustained period. Additional data quantifying the long-term benefits of IMRT, however, are needed.

  10. MUSKHELISHVILI'S METHOD APPLIED TO ELLIPTICAL AND LUBRICATED CIRCULAR INCLUSIONS IN GENERAL SHEAR

    E-Print Network [OSTI]

    Podladchikov, Yuri

    MUSKHELISHVILI'S METHOD APPLIED TO ELLIPTICAL AND LUBRICATED CIRCULAR INCLUSIONS IN GENERAL SHEAR and Elliptical Inclusions, Lubricated Inclusions, Mantled Inclusions, Pure and Simple Shear, Viscous Rheology

  11. Shear Connections for the Development of a Full-Depth Precast Concrete Deck System 

    E-Print Network [OSTI]

    Henley, Matthew D.

    2010-07-14

    National Cooperative Highway Research Program NS Nelson stud R R-bar shear connection within a pocket system SIP Stay-in-place TR Threaded rod shear connection TRC Threaded rod with coupler shear connection TRE Threaded rod post-installed in epoxy...-to-powder ratio a Width of shear test beam A cv Concrete shear interface area A s Area of one shear connector A sc Cross-sectional area of stud shear connector A se,v Effective cross-sectional area of a single anchor in shear vi A sf Area of steel...

  12. The impact of vertical shear on the sensitivity of tropical cyclogenes...

    Office of Scientific and Technical Information (OSTI)

    The impact of vertical shear on the sensitivity of tropical cyclogenesis to environmental rotation and thermodynamic state: TROPICAL CYCLOGENESIS AND SHEAR Citation Details...

  13. EVALUATION OF VOLUMETRIC THRESHOLD STRAIN CONSIDERING NOISY FEEDBACK SIGNALS FROM SIMPLE SHEAR DEVICE

    E-Print Network [OSTI]

    Schoenberg, Frederic Paik (Rick)

    EVALUATION OF VOLUMETRIC THRESHOLD STRAIN CONSIDERING NOISY FEEDBACK SIGNALS FROM SIMPLE SHEAR 90095 #12;set to illustrate how the volumetric threshold shear strain can be evaluated in consideration

  14. Comparison of architectures for two-step flash analog-to-digital converters 

    E-Print Network [OSTI]

    Reese, Robert Bryan

    1982-01-01

    A/D converters have been designed and fabricated in the last three to five ?om a survey of the literature it was discovered that the majority of these converters were of the successive approximation (SAP) type (Table I, page 4). This is because... the SAP converter offers a fast conversion time, a low complexity level and a small area requirement. Only one comparator, the design critical subcircuit of most converters, is needed in a SAP converter. Area requirements increase only moderately...

  15. Converting chemical energy of hydrogenated fuels into electricity

    E-Print Network [OSTI]

    - 1 - Fuel Cells Converting chemical energy of hydrogenated fuels into electricity Project Description Invented in 1839, fuels cells powered the Gemini and Apollo space missions, as well as the space shuttle. Although fuel cells have been successfully used in such applications, they have proven difficult

  16. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, M.C.; Merritt, B.T.; Penetrante, B.M.; Vogtlin, G.E.

    1999-04-06

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO{sub 2} in the presence of O{sub 2}. The second stage serves to convert NO{sub 2} to environmentally benign gases that include N{sub 2}, CO{sub 2}, and H{sub 2}O. By preconverting NO to NO{sub 2} in the first stage, the efficiency of the second stage for NO{sub x} reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO{sub 2} in the presence of O{sub 2} and includes platinum/alumina, e.g., Pt/Al{sub 2}O{sub 3} catalyst. A flow of hydrocarbons (C{sub x}H{sub y}) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO{sub 2} from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO{sub 2} to N{sub 2}, CO{sub 2}, and H{sub 2}O, and includes a {gamma}-Al{sub 2}O{sub 3}. The hydrocarbons and NO{sub x} are simultaneously reduced while passing through the second catalyst. 9 figs.

  17. Pre-converted nitric oxide gas in catalytic reduction system

    DOE Patents [OSTI]

    Hsiao, Mark C. (Livermore, CA); Merritt, Bernard T. (Livermore, CA); Penetrante, Bernardino M. (San Ramon, CA); Vogtlin, George E. (Fremont, CA)

    1999-01-01

    A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO.sub.2 in the presence of O.sub.2. The second stage serves to convert NO.sub.2 to environmentally benign gases that include N2, CO2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO.sub.2 in the presence of O.sub.2 and includes platinum/alumina, e.g., Pt/Al.sub.2 O.sub.3 catalyst. A flow of hydrocarbons (C.sub.x H.sub.y) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO.sub.2 from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO.sub.2 to N2, CO2, and H.sub.2 O, and includes a gamma-alumina .gamma.-Al.sub.2 O.sub.3. The hydrocarbons and NO.sub.x are simultaneously reduced while passing through the second catalyst.

  18. Multi-level converters for three-phase photovoltaic applications

    E-Print Network [OSTI]

    Lehman, Brad

    Multi-level converters for three-phase photovoltaic applications Renato M. Nakagomi, Ye Zhao, Brad a switching matrix device and photovoltaic (PV) panels. The approach is based on the dynamic reconfiguration photovoltaic PV panels. The number of PV panels that are connected to the load can be altered using dynamic

  19. Apparatus for converting biomass to a pumpable slurry

    DOE Patents [OSTI]

    Ergun, Sabri (Hillsborough, CA); Schaleger, Larry L. (Oakland, CA); Wrathall, James A. (Berkeley, CA); Yaghoubzadeh, Nasser (El Cerrito, CA)

    1986-01-01

    An apparatus used in the pretreatment of wood chips in a process for converting biomass to a liquid hydrocarbonaceous fuel. The apparatus functions to break down the wood chips to a size distribution that can be readily handled in a slurry form. Low maintenance operation is obtained by hydrolyzing the chips in a pressure vessel having no moving parts.

  20. Ability of Catalytic Converters to Reduce Air Pollution

    E-Print Network [OSTI]

    Nizkorodov, Sergey

    NOx - 1 Ability of Catalytic Converters to Reduce Air Pollution MEASUREMENT OF SELECTED AIR Air Pollution MEASUREMENT OF SELECTED AIR POLLUTANTS IN CAR EXHAUST INTRODUCTION Automobile engines of gasoline (hydrocarbons, CxHy) in air: CxHy + O2 CO2 + H2O + heat (1) When there is the correct balance

  1. Energy Savings Assessment for Digital-to-Analog Converter Boxes

    SciTech Connect (OSTI)

    Cheung, Hoi Ying Iris; Meier, Alan; Brown, Richard

    2011-01-18

    The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700 GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes.

  2. Everything Digital: Converting the world in 2 Exabytes

    SciTech Connect (OSTI)

    Lesk, Michael

    2003-11-05

    Nearly everything created today is in digital format: music is on digital CDs, documents come from word processing, still photography is switching to digital cameras and even movies are now edited digitally. What about the past? We have projects like the Million Book Project scanning one million books, and we know technically how to convert everything: the problems are legal, economic and organizational.

  3. REGULAR ARTICLE A comparison of methods for converting rhizotron root

    E-Print Network [OSTI]

    provide valuable information about plant root production, but measurements are usually made in units of root length per unit surface area of observation window surface. These measure- ment units developed to convert rhizotron measurement units into root mass production per unit ground area

  4. Multiport Converter Topologies for Distributed Energy System Applications 

    E-Print Network [OSTI]

    Hawke, Joshua

    2014-07-28

    . Next, three system designs are discussed: single-zone, dual-zone, and multi-zone. Each implements PSC technology and high-frequency isolated full-bridge converters to interface multiple fuel cell sources to a medium voltage grid via a single multilevel...

  5. Cycling firing method for bypass operation of bridge converters

    DOE Patents [OSTI]

    Zabar, Zivan (99-72 66th Rd., Apt. 9N, Forest Hills, NY 11375)

    1982-01-01

    The bridge converter comprises a number of switching elements and an electronic logic system which regulated the electric power levels by controlling the firing, i.e., the initiation of the conduction period of the switching elements. Cyclic firing of said elements allows the direct current to bypass the alternating current system with high power factor and negligible losses.

  6. Performance Assessment of the Wave Dragon Wave Energy Converter

    E-Print Network [OSTI]

    Hansen, René Rydhof

    Performance Assessment of the Wave Dragon Wave Energy Converter Based on the EquiMar Methodology S of the wave energy sector, device developers are called to provide reliable estimates on power performanceMar, Nissum Bredning, Hanstholm, North Sea, Ekofisk, Wave-to-wire, Wave energy. I. INTRODUCTION The wave

  7. Rayleigh-Taylor instabilities with sheared magnetic fields

    SciTech Connect (OSTI)

    Ruderman, M. S. [Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Terradas, J.; Ballester, J. L. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

    2014-04-20

    Magnetic Rayleigh-Taylor (MRT) instabilities may play a relevant role in many astrophysical problems. In this work the effect of magnetic shear on the growth rate of the MRT instability is investigated. The eigenmodes of an interface and a slab model under the presence of gravity are analytically calculated assuming that the orientation of the magnetic field changes in the equilibrium, i.e., there is magnetic shear. We solve the linearized magnetohydrodynamic equations in the incompressible regime. We find that the growth rate is bounded under the presence of magnetic shear. We have derived simple analytical expressions for the maximum growth rate, corresponding to the most unstable mode of the system. These expressions provide the explicit dependence of the growth rate on the various equilibrium parameters. For small angles the growth time is linearly proportional to the shear angle, and in this regime the single interface problem and the slab problem tend to the same result. On the contrary, in the limit of large angles and for the interface problem the growth time is essentially independent of the shear angle. In this regime we have also been able to calculate an approximate expression for the growth time for the slab configuration. Magnetic shear can have a strong effect on the growth rates of the instability. As an application of the results found in this paper we have indirectly determined the shear angle in solar prominence threads using their lifetimes and the estimation of the Alfvén speed of the structure.

  8. Piezoelectric shear wave resonator and method of making same

    DOE Patents [OSTI]

    Wang, J.S.; Lakin, K.M.; Landin, A.R.

    1985-05-20

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppM//sup 0/C.

  9. Piezoelectric shear wave resonator and method of making same

    DOE Patents [OSTI]

    Wang, Jin S. (Harbor City, CA); Lakin, Kenneth M. (Ames, IA); Landin, Allen R. (Ames, IA)

    1988-01-01

    An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppm/.degree.C.

  10. Coherent structures in compressible free-shear-layer flows

    SciTech Connect (OSTI)

    Aeschliman, D.P.; Baty, R.S.; Kennedy, C.A.; Chen, J.H.

    1997-08-01

    Large scale coherent structures are intrinsic fluid mechanical characteristics of all free-shear flows, from incompressible to compressible, and laminar to fully turbulent. These quasi-periodic fluid structures, eddies of size comparable to the thickness of the shear layer, dominate the mixing process at the free-shear interface. As a result, large scale coherent structures greatly influence the operation and efficiency of many important commercial and defense technologies. Large scale coherent structures have been studied here in a research program that combines a synergistic blend of experiment, direct numerical simulation, and analysis. This report summarizes the work completed for this Sandia Laboratory-Directed Research and Development (LDRD) project.

  11. The effect of dynamic simple shear on marine sediment 

    E-Print Network [OSTI]

    Carpenter, Samuel Harley

    1972-01-01

    radian where the difference is only ten percent. rt Then 6 =? h and: d9 r dt h This value is a constant for any one test. It gives a reasonable value to use for any one deformation rate, and will be called the shear deformation rate in this study... . The average strain to failure for the shear-viscometer tests is 0. 51 radians. This corresponds to 0. 14 inches defor- mation or 6. 6 percent strain. The values for shear strain varied between 4. 2 and 8. 9 percent strain to failure. This value...

  12. Optimisation of Shear Strengthened Reinforced Concrete Beams

    E-Print Network [OSTI]

    Yapa, Hiran D.; Lees, Janet M.

    2014-05-21

    fle nS nL nP S1/a S2/a S3/a 2 5 25 0.42 0.58 — 83.3 0.73 2 5 50 0.40 0.60 — 92.8 0.81 2 10 25 0.39 0.61 — 96.0 0.84 2 10 50 0.38 0.61 — 107.1 0.94 2 15 5 0.42 0.58 — 91.6 0.80 2 20 5 0.39 0.60 — 94.7 0.83 Mean 0.40 0.60 — — — SD 0.02 0.01 — — — 3 5 25... . Engineering Optimisation 39(4): 471–494. Hoult NA and Lees JM (2009a) Efficient CFRP strap configurations for the shear strengthening of reinforced concrete T-beams. ASCE Journal of Composites for Construction 13(1): 45–52. Hoult NA and Lees JM (2009b...

  13. Vane shear determination of the visco-elastic shear modulus of submarine sediments 

    E-Print Network [OSTI]

    Stevenson, Herbert Scott

    1973-01-01

    viscoelastic theory and torque versus rotation data from vane shear tests. The modu- lus, G(t), is described by the power law: G(t) = G, t where t is time, and G, and n are constants. G, and n are deter- mined from vane tests on deep sediment core samples.... G, is rota- tion angle dependent. The validity of the procedure is supported by predict1ons of in situ vane test torque versus rotation curves wh1ch agree favorably with data obtained using an in s1tu vane device. G, correlates with maximum vane...

  14. Propensity Score-based Comparison of Long-term Outcomes With 3-Dimensional Conformal Radiotherapy vs Intensity-Modulated Radiotherapy for Esophageal Cancer

    SciTech Connect (OSTI)

    Lin, Steven H., E-mail: SHLin@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Wang Lu [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Myles, Bevan [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Thall, Peter F. [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hofstetter, Wayne L.; Swisher, Stephen G. [Department of Thoracic Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Thoracic Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ajani, Jaffer A. [Department of Gastrointestinal Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Gastrointestinal Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Cox, James D.; Komaki, Ritsuko; Liao Zhongxing [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-12-01

    Purpose: Although 3-dimensional conformal radiotherapy (3D-CRT) is the worldwide standard for the treatment of esophageal cancer, intensity modulated radiotherapy (IMRT) improves dose conformality and reduces the radiation exposure to normal tissues. We hypothesized that the dosimetric advantages of IMRT should translate to substantive benefits in clinical outcomes compared with 3D-CRT. Methods and Materials: An analysis was performed of 676 nonrandomized patients (3D-CRT, n=413; IMRT, n=263) with stage Ib-IVa (American Joint Committee on Cancer 2002) esophageal cancers treated with chemoradiotherapy at a single institution from 1998-2008. An inverse probability of treatment weighting and inclusion of propensity score (treatment probability) as a covariate were used to compare overall survival time, interval to local failure, and interval to distant metastasis, while accounting for the effects of other clinically relevant covariates. The propensity scores were estimated using logistic regression analysis. Results: A fitted multivariate inverse probability weighted-adjusted Cox model showed that the overall survival time was significantly associated with several well-known prognostic factors, along with the treatment modality (IMRT vs 3D-CRT, hazard ratio 0.72, P<.001). Compared with IMRT, 3D-CRT patients had a significantly greater risk of dying (72.6% vs 52.9%, inverse probability of treatment weighting, log-rank test, P<.0001) and of locoregional recurrence (P=.0038). No difference was seen in cancer-specific mortality (Gray's test, P=.86) or distant metastasis (P=.99) between the 2 groups. An increased cumulative incidence of cardiac death was seen in the 3D-CRT group (P=.049), but most deaths were undocumented (5-year estimate, 11.7% in 3D-CRT vs 5.4% in IMRT group, Gray's test, P=.0029). Conclusions: Overall survival, locoregional control, and noncancer-related death were significantly better after IMRT than after 3D-CRT. Although these results need confirmation, IMRT should be considered for the treatment of esophageal cancer.

  15. Five-Year Outcomes, Cosmesis, and Toxicity With 3-Dimensional Conformal External Beam Radiation Therapy to Deliver Accelerated Partial Breast Irradiation

    SciTech Connect (OSTI)

    Rodríguez, Núria; Sanz, Xavier; Dengra, Josefa; Foro, Palmira; Membrive, Ismael; Reig, Anna; Quera, Jaume; Fernández-Velilla, Enric; Pera, Óscar; Lio, Jackson; Lozano, Joan; Algara, Manuel

    2013-12-01

    Purpose: To report the interim results from a study comparing the efficacy, toxicity, and cosmesis of breast-conserving treatment with accelerated partial breast irradiation (APBI) or whole breast irradiation (WBI) using 3-dimensional conformal external beam radiation therapy (3D-CRT). Methods and Materials: 102 patients with early-stage breast cancer who underwent breast-conserving surgery were randomized to receive either WBI (n=51) or APBI (n=51). In the WBI arm, 48 Gy was delivered to the whole breast in daily fractions of 2 Gy, with or without additional 10 Gy to the tumor bed. In the APBI arm, patients received 37.5 Gy in 3.75 Gy per fraction delivered twice daily. Toxicity results were scored according to the Radiation Therapy Oncology Group Common Toxicity Criteria. Skin elasticity was measured using a dedicated device (Multi-Skin-Test-Center MC-750-B2, CKelectronic-GmbH). Cosmetic results were assessed by the physician and the patients as good/excellent, regular, or poor. Results: The median follow-up time was 5 years. No local recurrences were observed. No significant differences in survival rates were found. APBI reduced acute side effects and radiation doses to healthy tissues compared with WBI (P<.01). Late skin toxicity was no worse than grade 2 in either group, without significant differences between the 2 groups. In the ipsilateral breast, the areas that received the highest doses (ie, the boost or quadrant) showed the greatest loss of elasticity. WBI resulted in a greater loss of elasticity in the high-dose area compared with APBI (P<.05). Physician assessment showed that >75% of patients in the APBI arm had excellent or good cosmesis, and these outcomes appear to be stable over time. The percentage of patients with excellent/good cosmetic results was similar in both groups. Conclusions: APBI delivered by 3D-CRT to the tumor bed for a selected group of early-stage breast cancer patients produces 5-year results similar to those achieved with conventional WBI.

  16. Numerical method for shear bands in ductile metal with inclusions

    SciTech Connect (OSTI)

    Plohr, Jee Yeon N [Los Alamos National Laboratory; Plohr, Bradley J [Los Alamos National Laboratory

    2010-01-01

    A numerical method for mesoscale simulation of high strain-rate loading of ductile metal containing inclusions is described. Because of small-scale inhomogeneities, such a composite material is prone to localized shear deformation (adiabatic shear bands). The modeling framework is the Generalized Method of Cells of Paley and Aboudi [Mech. Materials, vol. 14, pp. /27-139, 1992], which ensures that the micromechanical response of the material is reflected in the behavior of the composite at the mesoscale. To calculate the effective plastic strain rate when shear bands are present, the analytic and numerical analysis of shear bands by Glimm, Plohr, and Sharp [Mech. Materials, vol. 24, pp. 31-41, 1996] is adapted and extended.

  17. Estimating A Shear Modulus Of A Transversely Isotropic Formation

    E-Print Network [OSTI]

    Ellefsen, K. J.

    1990-01-01

    A method to estimate c[subscript 66], which is a shear modulus of a transversely isotropic formation (with its symmetry axis parallel to the borehole), is developed and tested. The inversion for c[subscript 66] is based ...

  18. Interfacial colloidal monolayers under steady shear: structure and flow profiles

    E-Print Network [OSTI]

    Ivo Buttinoni; Zachary A. Zell; Todd M. Squires; Lucio Isa

    2015-09-11

    We study the coupling between the structural dynamics and rheological response of charged colloidal monolayers at water/oil interfaces, driven into steady shear by a microdisk rotating at a controlled angular velocity. The flow causes particles to layer into rotating concentric rings linked to the local, position-dependent shear rate, which triggers two distinct dynamical regimes: particles move continuously "Flowing") close to the microdisk, or exhibit intermittent "Hopping" between local energy minima farther away. The shear-rate dependent surface viscosity of a monolayer can be extracted from an interfacial stress balance, giving "macroscopic" flow curves whose behavior corresponds to the distinct microscopic regimes of particle motion. Hopping Regions correspond to a surface yield stress $\\eta \\sim \\tau_S^Y \\dot{\\gamma}^{-1}$, whereas Flowing Regions exhibit surface viscosities with power-law shear-thinning characteristics.

  19. Reflective cracking of shear keys in multi-beam bridges 

    E-Print Network [OSTI]

    Sharpe, Graeme Peter

    2009-06-02

    strength to resist cracking from vehicular loads, but uneven temperature changes and shrinkage strains cause high tensile stresses in the shear key regions and lead to reflective cracking. The analyses showed the highest stresses were often times near...

  20. Interfacial colloidal monolayers under steady shear: structure and flow profiles

    E-Print Network [OSTI]

    Ivo Buttinoni; Zachary A. Zell; Todd M. Squires; Lucio Isa

    2015-04-01

    We study the coupling between the structural dynamics and rheological response of charged colloidal monolayers at water/oil interfaces, driven into steady shear by a microdisk rotating at a controlled angular velocity. The flow causes particles to layer into rotating concentric rings linked to the local, position-dependent shear rate, which triggers two distinct dynamical regimes: particles move continuously "Flowing") close to the microdisk, or exhibit intermittent "Hopping" between local energy minima farther away. The shear-rate dependent surface viscosity of a monolayer can be extracted from an interfacial stress balance, giving "macroscopic" flow curves whose behavior corresponds to the distinct microscopic regimes of particle motion. Hopping Regions correspond to a surface yield stress $\\eta \\sim \\tau_S^Y \\dot{\\gamma}^{-1}$, whereas Flowing Regions exhibit surface viscosities with power-law shear-thinning characteristics.

  1. Shear-wave splitting and reservoir crack characterization: the...

    Open Energy Info (EERE)

    of its geothermal potential and day-to-day production. To detect the geometry and density of fracture systems we applied the shear-wave splitting technique to a large number...

  2. Polymer dynamics in random flow with mean shear K. Turitsyn

    E-Print Network [OSTI]

    Fominov, Yakov

    Polymer dynamics in random flow with mean shear K. Turitsyn Landau Institute for theoretical;Outline · Motivation: Elastic turbulence · Experimental setup · Flow and polymer models · Results: 1. Angular statistics 2. Polymer elongation distribution · Conclusion #12;Elastic Turbulence Elastic

  3. Linear plasmoid instability of thin current sheets with shear flow

    SciTech Connect (OSTI)

    Ni Lei; Germaschewski, Kai; Huang Yimin; Sullivan, Brian P.; Yang Hongang; Bhattacharjee, Amitava

    2010-05-15

    This paper presents linear analytical and numerical studies of plasmoid instabilities in the presence of shear flow in high-Lundquist-number plasmas. Analysis demonstrates that the stability problem becomes essentially two dimensional as the stabilizing effects of shear flow become more prominent. Scaling results are presented for the two-dimensional instabilities. An approximate criterion is given for the critical aspect ratio of thin current sheets at which the plasmoid instability is triggered.

  4. The rheology and processing of “edge sheared” colloidal polymer opals

    SciTech Connect (OSTI)

    Wong, Hon Sum; Mackley, Malcolm Butler, Simon; Baumberg, Jeremy; Snoswell, David; Finlayson, Chris; Zhao, Qibin

    2014-03-15

    This paper is concerned with the rheology and processing of solvent-free core shell “polymer opals” that consist of a soft outer shell grafted to hard colloidal polymer core particles. Strong iridescent colors can be produced by shearing the material in a certain way that causes the initially disordered spheres to rearrange into ordered crystalline structures and produce colors by diffraction and interference of multiple light scattering, similar to gemstone opals. The basic linear viscoelastic rheology of a polymer opal sample was determined as a function of temperature, and the material was found to be highly viscoelastic at all tested temperatures. A Cambridge multipass rheometer was specifically modified in order to make controlled mechanical measurements of initially disordered polymer opal tapes that were sandwiched between protective polyethylene terephthalate sheets. Axial extension, simple shear, and a novel “edge shearing” geometry were all evaluated, and multiple successive experiments of the edge shearing test were carried out at different temperatures. The optical development of colloidal ordering, measured as optical opalescence, was quantified by spectroscopy using visible backscattered light. The development of opalescence was found to be sensitive to the geometry of deformation and a number of process variables suggesting a complex interaction of parameters that caused the opalescence. In order to identify aspects of the deformation mechanism of the edge shearing experiment, a separate series of in situ optical experiments were carried out and this helped indicate the extent of simple shear generated with each edge shear deformation. The results show that strong ordering can be induced by successive edge shearing deformation. The results are relevant to polymer opal rheology, processing, and mechanisms relating to ordering within complex viscoelastic fluids.

  5. Double scaling and intermittency in shear dominated flows

    E-Print Network [OSTI]

    C. M. Casciola; R. Benzi; P. Gualtieri; B. Jacob; R. Piva

    2001-04-18

    The Refined Kolmogorov Similarity Hypothesis is a valuable tool for the description of intermittency in isotropic conditions. For flows in presence of a substantial mean shear, the nature of intermittency changes since the process of energy transfer is affected by the turbulent kinetic energy production associated with the Reynolds stresses. In these conditions a new form of refined similarity law has been found able to describe the increased level of intermittency which characterizes shear dominated flows. Ideally a length scale associated with the mean shear separates the two ranges, i.e. the classical Kolmogorov-like inertial range, below, and the shear dominated range, above. However, the data analyzed in previous papers correspond to conditions where the two scaling regimes can only be observed individually. In the present letter we give evidence of the coexistence of the two regimes and support the conjecture that the statistical properties of the dissipation field are practically insensible to the mean shear. This allows for a theoretical prediction of the scaling exponents of structure functions in the shear dominated range based on the known intermittency corrections for isotropic flows. The prediction is found to closely match the available numerical and experimental data.

  6. How does a thermal binary crystal break under shear?

    E-Print Network [OSTI]

    Tobias Horn; Hartmut Löwen

    2014-11-21

    When exposed to strong shearing, the particles in a crystal will rearrange and ultimately, the crystal will break by forming large nonaffine defects. Even for the initial stage of this process, only little effort has been devoted to the understanding of the breaking process on the scale of the individual particle size for thermalized mixed crystals. Here, we explore the shear-induced breaking for an equimolar two-dimensional binary model crystal with a high interaction asymmetry between the two different species such that the initial crystal has an intersecting square sublattice of the two constituents. Using Brownian dynamics computer simulations, we show that the combination of shear and thermal fluctuations leads to a characteristic hierarchical breaking scenario where initially, the more strongly coupled particles are thermally distorted, paving the way for the weakly coupled particles to escape from their cage. This in turn leads to mobile defects which may finally merge, proliferating a cascade of defects, which triggers the final breakage of the crystal. This scenario is in marked contrast to the breakage of one-component crystals close to melting. Moreover, we explore the orientational dependence of the initial shear direction relative to the crystal orientation and compare this to the usual melting scenario without shear. Our results are verifiable in real-space experiments of superparamagnetic colloidal mixtures at a pending air-water interface in an external magnetic field where the shear can be induced by an external laser field.

  7. Suppression of Neoclassical Tearing Modes by the Magnetic Well in Shear-Optimised Tokamak Discharges

    E-Print Network [OSTI]

    Suppression of Neoclassical Tearing Modes by the Magnetic Well in Shear-Optimised Tokamak Discharges

  8. Discharging a DC bus capacitor of an electrical converter system

    DOE Patents [OSTI]

    Kajouke, Lateef A; Perisic, Milun; Ransom, Ray M

    2014-10-14

    A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.

  9. Process for converting cellulosic materials into fuels and chemicals

    DOE Patents [OSTI]

    Scott, C.D.; Faison, B.D.; Davison, B.H.; Woodward, J.

    1994-09-20

    A process is described for converting cellulosic materials, such as waste paper, into fuels and chemicals utilizing enzymatic hydrolysis of the major constituent of paper, cellulose. A waste paper slurry is contacted by cellulase in an agitated hydrolyzer. The cellulase is produced from a continuous, columnar, fluidized-bed bioreactor utilizing immobilized microorganisms. An attrition mill and a cellobiase reactor are coupled to the agitated hydrolyzer to improve reaction efficiency. The cellulase is recycled by an adsorption process. The resulting crude sugars are converted to dilute product in a fluidized-bed bioreactor utilizing microorganisms. The dilute product is concentrated and purified by utilizing distillation and/or a biparticle fluidized-bed bioreactor system. 1 fig.

  10. Low work function material development for the microminiature thermionic converter.

    SciTech Connect (OSTI)

    Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan; Jennison, Dwight Richard

    2004-03-01

    Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.

  11. An aid to convert spreadsheets to higher quality presentations 

    E-Print Network [OSTI]

    Olajide, Wasiu Olaniyi

    2005-08-29

    with CALC. CALC is available on all common operating systems and has a well documented and easily accessible Java Application Programming Interface. 6 CHAPTER III QUALITY PRESENTATIONS A. Spreadsheets as Information Conveyors Tables are a good way to show...Office using the Java Application Programming Interface. The contents of the spreadsheet are extracted passed on to the Data Storage module. 2. Canonical Data Storage The converted data is stored in XML [16] format using the Document Object Model [17]. XML...

  12. Low current plasmatron fuel converter having enlarged volume discharges

    DOE Patents [OSTI]

    Rabinovich, Alexander (Swampscott, MA); Alexeev, Nikolai (Moscow, RU); Bromberg, Leslie (Sharon, MA); Cohn, Daniel R. (Chestnut Hill, MA); Samokhin, Andrei (Moscow, RU)

    2009-10-06

    A novel apparatus and method is disclosed for a plasmatron fuel converter ("plasmatron") that efficiently uses electrical energy to produce hydrogen rich gas. The volume and shape of the plasma discharge is controlled by a fluid flow established in a plasma discharge volume. A plasmatron according to this invention produces a substantially large effective plasma discharge volume allowing for substantially greater volumetric efficiency in the initiation of chemical reactions within a volume of bulk fluid reactant flowing through the plasmatron.

  13. Catalyst for converting synthesis gas to liquid motor fuels

    DOE Patents [OSTI]

    Coughlin, Peter K. (Yorktown Heights, NY)

    1986-01-01

    The addition of an inert metal component, such as gold, silver or copper, to a Fischer-Tropsch catalyst comprising cobalt enables said catalyst to convert synthesis gas to liquid motor fuels at about 240.degree.-370.degree. C. with advantageously reduced selectivity of said cobalt for methane in said conversion. The catalyst composition can advantageously include a support component, such as a molecular sieve, co-catalyst/support component or a combination of such support components.

  14. Intensive neutrino source on the base of lithium converter

    E-Print Network [OSTI]

    V. I. Lyashuk; Yu. S Lutostansky

    2015-04-13

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neutron flux (i.e., powerful neutron source) is requested for realization of considered neutrino sources (neutrino factories). Different realizations of lithium antineutrino sources (lithium converter on the base of high purified 7Li isotope) are discussed: static regime (i.e., without transport of 8Li isotope to the neutrino detector); dynamic regime (transport of 8Li isotope to the remote detector in a closed cycle); an operation of lithium converter in tandem of accelerator with a neutron-producing target on the base of tungsten, lead or bismuth. Different chemical compounds of lithium (as the substance of the converter) are considered. Heavy water solution of LiOD is proposed as a serious alternative to high-pure 7Li in a metallic state.

  15. Low current plasmatron fuel converter having enlarged volume discharges

    DOE Patents [OSTI]

    Rabinovich, Alexander; Alexeev, Nikolai; Bromberg, Leslie; Cohn, Daniel R.; Samokhin, Andrei

    2005-04-19

    A novel apparatus and method is disclosed for a plasmatron fuel converter (""plasmatron"") that efficiently uses electrical energy to produce hydrogen rich gas. The volume and shape of the plasma discharge is controlled by a fluid flow established in a plasma discharge volume. A plasmatron according to this invention produces a substantially large effective plasma discharge volume allowing for substantially greater volumetric efficiency in the initiation of chemical reactions within a volume of bulk fluid reactant flowing through the plasmatron.

  16. The microstructure and rheology of a model, thixotropic nanoparticle gel under steady shear and large amplitude oscillatory shear (LAOS)

    SciTech Connect (OSTI)

    Min Kim, Jung; Kate Gurnon, A.; Wagner, Norman J., E-mail: wagnernj@udel.edu [Department of Chemical and Biomolecular Engineering and Center for Neutron Science, University of Delaware, Newark, Delaware 19716 (United States); Eberle, Aaron P. R. [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Porcar, Lionel [NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 and Institut Laue-Langevin, BP 156, F-38042 Grenoble Cedex 9 (France)

    2014-09-01

    The microstructure-rheology relationship for a model, thermoreversible nanoparticle gel is investigated using a new technique of time-resolved neutron scattering under steady and time-resolved large amplitude oscillatory shear (LAOS) flows. A 21 vol. % gel is tested with varying strength of interparticle attraction. Shear-induced structural anisotropy is observed as butterfly scattering patterns and quantified through an alignment factor. Measurements in the plane of flow show significant, local anisotropy develops with alignment along the compressional axis of flow, providing new insights into how gels flow. The microstructure-rheology relationship is analyzed through a new type of structure-Lissajous plot that shows how the anisotropic microstructure is responsible for the observed LAOS response, which is beyond a response expected for a purely viscous gel with constant structure. The LAOS shear viscosities are observed to follow the “Delaware-Rutgers” rule. Rheological and microstructural data are successfully compared across a broad range of conditions by scaling the shear rate by the strength of attraction, providing a method to compare behavior between steady shear and LAOS experiments. However, important differences remain between the microstructures measured at comparatively high frequency in LAOS experiments and comparable steady shear experiments that illustrate the importance of measuring the microstructure to properly interpret the nonlinear, dynamic rheological response.

  17. Development of a Multi-directional Direct Simple Shear Testing Device for Characterization of the Cyclic Shear Response of Marine Clays 

    E-Print Network [OSTI]

    Rutherford, Cassandra Jane

    2012-07-16

    This dissertation describes the development of a new multi-directional direct simple shear testing device, the Texas A&M Multi-directional Direct Simple Shear (TAMU-MDSS), for testing marine soil samples under conditions, ...

  18. Design and characterization of a radio-frequency dc/dc power converter

    E-Print Network [OSTI]

    Jackson, David A. (David Alexander)

    2005-01-01

    The use of radio-frequency (RF) amplifier topologies in dc/dc power converters allows the operating frequency to be increased by more than two orders of magnitude over the frequency of conventional converters. This enables ...

  19. GUIDELINES FOR CONVERTING FTN4 PROGRAMS TO FTN5 AND THE NEW FORTRAN-77 STANDARD

    E-Print Network [OSTI]

    Friedman, R.

    2012-01-01

    1st Edition GUIDELINES FOR CONVERTING FTN4 PROGRAMS TO FTN5Edition (August 79) Guidelines for Converting FTN4 Programsprogram F45 are described in each instance. lst Edition (

  20. Design techniques for low noise and high speed A/D converters 

    E-Print Network [OSTI]

    Gupta, Amit Kumar

    2009-05-15

    subscriber line (ADSL) modems, cellular systems, high accuracy instrumentation, and medical imaging systems. This thesis suggests some design techniques for such high resolution and high sampling rate A/D converters. As the A/D converter performance keeps...

  1. Wide input range DC-DC converter with digital control scheme 

    E-Print Network [OSTI]

    Harfman Todorovic, Maja

    2006-04-12

    :1 voltage variation as well as a slow transient response. The proposed approach consists of two stages: a primary three-level boost converter stage cascaded with a high frequency, isolated boost converter topology, which provides a higher voltage gain...

  2. High-Frequency Resonant SEPIC Converter With Wide Input and Output Voltage Ranges

    E-Print Network [OSTI]

    Hu, Jingying

    This paper presents a resonant single-ended-primary-inductor-converter (SEPIC) converter and control method suitable for high frequency (HF) and very high frequency (VHF) dc-dc power conversion. The proposed design provides ...

  3. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    A review of wave energy converter technology. Proceedings ofWave energy utilization: A review of the technologies. Re-decades. With the technology of wave-energy convert- ers(

  4. The impulsive effects of momentum transfer on the dynamics of a novel ocean wave energy converter

    E-Print Network [OSTI]

    Diamond, CA; O'Reilly, OM; Sava?, O

    2013-01-01

    7] J. Falnes, A review of wave-energy extraction, MarineOrazov, O. M. O’Reilly, O. wave energy converter, Journal ofsimple model for a novel wave energy converter: non-resonant

  5. Computer-aided optimization of DC/DC converters for automotive applications

    E-Print Network [OSTI]

    Neugebauer, Timothy C.

    This paper investigates computer-aided optimization of DC/DC converters, with a focus on converters for dual-voltage automotive electrical systems. A new CAD optimization approach based on Monte Carlo search methods is ...

  6. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    design optimization of wave energy converters con- sistingN. Sahinkaya. A review of wave energy converter technology.2009. [6] A.F.O. Falc˜ao. Wave energy utilization: A review

  7. Outphasing Control of Gallium Nitride based Very High Frequency Resonant Converters

    E-Print Network [OSTI]

    Madsen, Mickey P.

    In this paper an outphasing modulation control method suitable for line regulation of very high frequency resonant converters is described.

  8. A Predictive power control of Doubly Fed Induction Generator for Wave Energy Converter

    E-Print Network [OSTI]

    Brest, Université de

    Switchgear Wave converter control Gear hal-01023509,version1-13Jul2014 Author manuscript, published in "IEEE

  9. Aalborg Universitet Two phase interleaved buck converter for driving high power LEDs

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet Two phase interleaved buck converter for driving high power LEDs Beczkowski. (2011). Two phase interleaved buck converter for driving high power LEDs. In Proceedings of the 14th #12;Two phase interleaved buck converter for driving high power LEDs Szymon Bczkowski, Stig Munk

  10. 111-f:l.~A PfC, qs: Hoo control of boost converters

    E-Print Network [OSTI]

    ,I-.; ... 111- f:l.~A PfC, qs: f'EEEin !f Hoo control of boost converters Rami NAIM, George WEISS at low frequencies). In a case study, for a typical low power boost converter, we obtain significantly\\vitching frequency. Boost and buck-boost converters (in continuous conduction mode) have a zero in the right half

  11. Very High Frequency Resonant Boost Converters Robert C. N. Pilawa-Podgurski

    E-Print Network [OSTI]

    Perreault, Dave

    Very High Frequency Resonant Boost Converters Robert C. N. Pilawa-Podgurski , Anthony D. Sagneri introduces a resonant boost converter topology and control method suitable for designs at very high frequency of the new resonant boost dc- dc converter topology. The design is optimized for low device stress and very

  12. PWM CONVERTERS WITH RESISTIVE INPUT Sam Ben-Yaakov and llya Zeltser

    E-Print Network [OSTI]

    and small signal responses of a Boost converter applied in APFC application. To make the input resistive be described by a simple intuitive reasoning in relation to the Boost converter (Fig. la). It is assumedthat (b) Fig. I. The Boost converter (a) and its behavioral average model (b) (after [7,8]). #12;ill

  13. MODELING OF HIGH-POWER-FACTOR RECTIFIERS BASED ON SWITCHING CONVERTERS

    E-Print Network [OSTI]

    boost [l]and up/down (flyback, kuk, Sepic, etc.) converters [a]. The purpose of this paper is to present. Specific results are discussed in detail for boost and up/down converters, which are most frequently usedMODELING OF HIGH-POWER-FACTOR RECTIFIERS BASED ON SWITCHING CONVERTERS WITH NONLINEAR

  14. FPGA based digital controller for switch-mode converter P-2013-025 Student: Yaron Huber

    E-Print Network [OSTI]

    control scheme for DC-DC converters such as: boost or buck-boost. The control scheme is designed of minimal deviation control scheme on Boost converter using PSIM #12;2. Realization: Minimaldeviationcontroller-FPGA DC Buck - Boost converter Vin Inductor Load CapacitorSwitch Vout IL PCM main computational

  15. Design of a Boost Power Factor Correction Converter Using Optimization Techniques Sergio Busquets-Monge1

    E-Print Network [OSTI]

    Lindner, Douglas K.

    Design of a Boost Power Factor Correction Converter Using Optimization Techniques Sergio Busquets Foundation under Award Number EEC-9731677. #12;Design of a Boost Power Factor Correction Converter Using of a boost power factor correction front-end converter with an input electromagnetic interference filter

  16. I-A Modulated Digitally Controlled Non-Inverting Buck-Boost Converter for

    E-Print Network [OSTI]

    I-A Modulated Digitally Controlled Non-Inverting Buck-Boost Converter for WCDMA RF Power Amplifiers.edu Abstract- This paper focuses on the non-inverting buck- boost converter supplying an adjustable DC voltage the WCDMA RFPA settling time requirements. 1. INTRODUCTION Non-inverting buck-boost DC-DC power converter

  17. Designing an Accurate and Robust LC-Compliant Asynchronous Boost DCDC Converter

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    Designing an Accurate and Robust LC-Compliant Asynchronous Boost DC­DC Converter Neeraj Keskar in buck converters, little has been done in boosting applications. This paper presents an asynchronous boost converter and describes how LC variations affect stability, steady-state error, and switching

  18. Synthesis of Impedance Using Switching Converters Joe C.P. Liu

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    and a pair of switches, such as the buck, buck-boost and boost converters. The switches are switched Synthesis of Impedance Using Switching Converters Joe C.P. Liu Chi K. Tse Franki N.K. Poon M converters is stud- ied in this paper. We begin with showing that any impedance can be synthesized

  19. A CHAOS MODEL OF SUBHARMONIC OSCILLATIONS IN CURRENT MODE PWM BOOST CONVERTERS

    E-Print Network [OSTI]

    A CHAOS MODEL OF SUBHARMONIC OSCILLATIONS IN CURRENT MODE PWM BOOST CONVERTERS Isaac Zafrany in a current mode PWM Boost converter under open and closed outer- loop conditions. A simple expression and explain by a Chaos model the behavior of a CM Boost converter under open and closed outer loop situations

  20. Controlling Chaos in DC/DC Converters Using Optimal Resonant Parametric Perturbation

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    perturba- tion method for controlling chaos in a current-mode con- trolled buck-boost converter of control. Specifically we make a chaotic buck-boost converter operate in an unstable period-1 orbit by a more complicated feedback chaos control method. II. CURRENT-MODE CONTROLLED BUCK-BOOST CONVERTER A

  1. BIFURCATION ANALYSIS OF A POWER-FACTOR-CORRECTION BOOST CONVERTER: UNCOVERING FAST-SCALE INSTABILITY

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    BIFURCATION ANALYSIS OF A POWER-FACTOR-CORRECTION BOOST CONVERTER: UNCOVERING FAST to a power-factor-correc- tion (PFC) boost converter to examine the fast-scale insta- bility problem to a current-programmed boost converter. In this paper, we study the onset of period-doubling (fast-scale) in

  2. Generalized Steady-state Analysis of Multiphase Interleaved Boost Converter with Coupled Inductors

    E-Print Network [OSTI]

    Lipo, Thomas

    2005-38 Generalized Steady-state Analysis of Multiphase Interleaved Boost Converter with Coupled interleaved boost converter with coupled inductors H.-B. Shin, J.-G. Park, S.-K. Chung, H.-W. Lee and T.A. Lipo Abstract: The generalised steady-state analysis of the multi-phase interleaved boost converter

  3. General Control for Boost PFC Converter from a Sliding Mode Viewpoint

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    4452 General Control for Boost PFC Converter from a Sliding Mode Viewpoint Grace Chu, Siew control methodology for the boost PFC converter based on sliding mode control theory. The resulting rule is derived for the boost PFC converter. The aim is to provide input current tracking under all

  4. Design Optimization of Power Electronics Circuits using Genetic Algorithms A Boost PFC Converter Example

    E-Print Network [OSTI]

    Lindner, Douglas K.

    Design Optimization of Power Electronics Circuits using Genetic Algorithms ­ A Boost PFC Converter with a developed software tool for designing a low-cost boost power factor correction (PFC) front-end converter presents an approach to discrete design optimization of a complete power electronics converter

  5. Development of a 55 kW 3X DC-DC Converter for HEV Systems

    E-Print Network [OSTI]

    Tolbert, Leon M.

    efficiency provide the great potential for the very high temperature operation. The circuit parameter design converter and a traction motor to drive the vehicle. In most commercial HEV systems, the power converter, 37996 Abstract--The design of a 55 kW 3X dc-dc converter is presented for hybrid electric vehicle (HEV

  6. CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland

    E-Print Network [OSTI]

    Haller, Merrick

    gradient technologies. This paper is focused on Ocean Wave Energy Converters (OWECs) and the needCHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland ABSTRACT Ocean Wave Energy Converters (OWECs) operating on the water surface are subject to storms

  7. Analysis and design of matrix converters for adjustable speed drives and distributed power sources 

    E-Print Network [OSTI]

    Cha, Han Ju

    2004-11-15

    -link. The new converter provides flexible voltage transfer ratio and galvanic isolation between input and output ac sources. Finally, the matrix converter concept is extended to dc/ac conversion from ac/ac conversion. The new dc/ac direct converter consists...

  8. Aalborg Universitet SiC heat pump converters with support for voltage unbalance in distribution grids

    E-Print Network [OSTI]

    Munk-Nielsen, Stig

    Aalborg Universitet SiC heat pump converters with support for voltage unbalance in distribution (APA): Trintis, I., Douglass, P., Maheshwari, R., & Munk-Nielsen, S. (2015). SiC heat pump converters.aau.dk on: november 29, 2015 #12;SiC heat pump converters with support for voltage unbalance in distribution

  9. Method for designing modulo {2n Binary-to-RNS converters

    E-Print Network [OSTI]

    Sousa, Leonel

    Method for designing modulo {2n ± k} Binary-to-RNS converters Hector Pettenghi1, Ricardo Chaves1-based modulo {2n ± k} Binary-to-RNS converters is pro- posed. Efficient modulo {2n ± k} converters can be used to support well balanced RNS moduli sets with large dynamic ranges. Moreover, a novel selection method

  10. Real-Time Model-Based Fault Diagnosis for Switching Power Converters

    E-Print Network [OSTI]

    Sanders, Seth

    demonstration for a 1.2 kW rack-level uninterruptable power supply (UPS) dc-dc converter for data center for a 1.2 kW rack- level uninterruptable power supply (UPS) dc-dc converter for data center applicationsReal-Time Model-Based Fault Diagnosis for Switching Power Converters Jason Poon, Ioannis C

  11. An Improved MPPT Interleaved Boost Converter for Solar Electric Vehicle Application

    E-Print Network [OSTI]

    Boyer, Edmond

    . The converter is connected between the photovoltaic power generation and dc bus in a multisource energy storage dc-dc converter; Solar electric vehicle; MPPT; Energy storage system. I. INTRODUCTION Photovoltaic energy storage system of a SEV Furthermore, for high-power applications, interleaved converters have been

  12. An Automated System for Converting App Inventor Apps to Java Interface For Creating and Managing Projects

    E-Print Network [OSTI]

    Gray, Jeffrey G.

    An Automated System for Converting App Inventor Apps to Java Interface For Creating and Managing of Computer Science Graphical Environment For Creating Layouts MIT App Inventor An Automated System for Converting App Inventor Apps to JavaAn Automated System for Converting App Inventor Apps to JavaAn Automated

  13. Light-weight DC to very high voltage DC converter

    DOE Patents [OSTI]

    Druce, R.L.; Kirbie, H.C.; Newton, M.A.

    1998-06-30

    A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

  14. Processes for converting lignocellulosics to reduced acid pyrolysis oil

    DOE Patents [OSTI]

    Kocal, Joseph Anthony; Brandvold, Timothy A

    2015-01-06

    Processes for producing reduced acid lignocellulosic-derived pyrolysis oil are provided. In a process, lignocellulosic material is fed to a heating zone. A basic solid catalyst is delivered to the heating zone. The lignocellulosic material is pyrolyzed in the presence of the basic solid catalyst in the heating zone to create pyrolysis gases. The oxygen in the pyrolysis gases is catalytically converted to separable species in the heating zone. The pyrolysis gases are removed from the heating zone and are liquefied to form the reduced acid lignocellulosic-derived pyrolysis oil.

  15. Bi-Directional DC-DC Converter for PHEV Applications

    SciTech Connect (OSTI)

    Abas Goodarzi

    2011-01-31

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  16. A single-inductor switching DC-DC converter with five outputs and ordered power-distributive control

    E-Print Network [OSTI]

    Le, Hanh-Phuc; Chae, Chang-Seok; Lee, Kwang-Chan; Wang, Se-Won; Cho, Gyu-Ha; Cho, Gyu-Hyeong

    2007-01-01

    integrated current mode boost converter in standard 3.3=5-Vef?ciency CMOS DC-DC boost converter with current sensingdeveloping reset ICs, boost converters for PM OLED, and SIMO

  17. Nonequilibrium Structure of Colloidal Dumbbells under Oscillatory Shear

    E-Print Network [OSTI]

    Nils Heptner; Fangfang Chu; Yan Lu; Peter Lindner; Matthias Ballauff; Joachim Dzubiella

    2015-09-02

    We investigate the nonequilibrium behavior of dense, plastic-crystalline suspensions of mildly anisotropic colloidal hard dumbbells under the action of an oscillatory shear field by employing Brownian dynamics computer simulations. In particular, we extend previous investigations, where we uncovered novel nonequilibrium phase transitions, to other aspect ratios and to a larger nonequilibrium parameter space, that is, a wider range of strains and shear frequencies. We compare and discuss selected results in the context of novel scattering and rheological experiments. Both simulations and experiments demonstrate that the previously found transitions from the plastic crystal phase with increasing shear strain also occur at other aspect ratios. We explore the transition behavior in the strain-frequency phase and summarize it in a nonequilibrium phase diagram. Additionally, the experimental rheology results hint at a slowing down of the colloidal dynamics with higher aspect ratio.

  18. Combined Ideal and Kinetic Effects on Reversed Shear Alfven Eigenmodes

    SciTech Connect (OSTI)

    N.N. Gorelenkov, G.J. Kramer, and R. Nazikian

    2011-05-23

    A theory of Reversed Shear Alfven Eigenmodes (RSAEs) is developed for reversed magnetic field shear plasmas when the safety factor minimum, qmin, is at or above a rational value. The modes we study are known sometimes as either the bottom of the frequency sweep or the down sweeping RSAEs. We show that the ideal MHD theory is not compatible with the eigenmode solution in the reversed shear plasma with qmin above integer values. Corrected by special analytic FLR condition MHD dispersion of these modes nevertheless can be developed. Large radial scale part of the analytic RSAE solution can be obtained from ideal MHD and expressed in terms of the Legendre functions. The kinetic equation with FLR effects for the eigenmode is solved numerically and agrees with the analytic solutions. Properties of RSAEs and their potential implications for plasma diagnostics are discussed.

  19. Ballooning instabilities in tokamaks with sheared toroidal flows

    SciTech Connect (OSTI)

    Waelbroeck, F.L.; Chen, L.

    1990-11-01

    The stability of ballooning modes in the presence of sheared toroidal flows is investigated. The eigenmodes are shown to be related by a Fourier transformation to the non-exponentially growing Floquet solutions found by Cooper. It is further shown that the problem cannot be reduced further than to a two dimensional partial differential equation. Next, the generalized ballooning equation is solved analytically for a circular tokamak equilibrium with sonic flows, but with a small rotation shear compared to the sound speed. With this ordering, the centrifugal forces are comparable to the pressure gradient forces driving the instability, but coupling of the mode with the sound wave is avoided. A new stability criterion is derived which explicitly demonstrates that flow shear is stabilizing at constant centrifugal force gradient. 34 refs.

  20. Physical origin of shear-banding in jammed systems

    E-Print Network [OSTI]

    Philippe Coussot; Guillaume Ovarlez

    2010-07-30

    Jammed systems all have a yield stress. Among these materials some have been shown to shear-band but it is as yet unclear why some materials develop shear-band and some others do not. In order to rationalize existing data concerning the flow characteristics of jammed systems and in particular understand the physical origin of such a difference we propose a simple approach for describing the steady flow behaviour of yield stress fluids, which retains only basic physical ingredients. Within this frame we show that in the liquid regime the behaviour of jammed systems turns from that of a simple yield stress fluid (exhibiting homogeneous flows) to a shear-banding material when the ratio of a characteristic relaxation time of the system to a restructuring time becomes smaller than 1, thus suggesting a possible physical origin of these trends.

  1. Self-contained pipe cutting shear. Innovative technology summary report

    SciTech Connect (OSTI)

    NONE

    1998-11-01

    The US Department of Energy (DO) is in the process of decontaminating and decommissioning (D and D) many of its nuclear facilities throughout the country. Facilities have to be dismantled and demolition waste must be sized into manageable pieces for handling and disposal. Typically, the facilities undergoing D and D are contaminated, either chemically, radiologically, or both. In its D and D work, the DOE was in need of a tool capable of cutting steel and stainless steel pipe up to 6.4 cm in diameter. The self-contained pipe cutting shear was developed by Lukas Hydraulic GmbH and Co. KG to cut pipes up to 6.4 cm (2.5 in.) in diameter. This tool is a portable, hand-held hydraulic shear that is powered by a built-in rechargeable battery or a portable auxiliary rechargeable battery. Adding to its portability, it contains no hydraulic fluid lines or electrical cords, making it useful in congested areas or in areas with no power. Both curved and straight blades can be attached, making it adaptable to a variety of conditions. This tool is easy to set up, operates quietly, and cuts through pipes quickly. It is especially useful on contaminated pipes, as it crimps the ends while cutting and produces no residual cuttings. This shear is a valuable alternative to baseline technologies such as portable band saws, electric hacksaws, and other hydraulic shears. Costs using the innovative shear for cutting 2.5 cm (1-in.) pipe, for example, are comparable to costs using a conventional shear, approximately 80% of portable bandsaw costs and half of electric hacksaw costs.

  2. Shear zone refraction and deflection in layered granular materials

    E-Print Network [OSTI]

    Tamas Borzsonyi; Tamas Unger; Balazs Szabo

    2009-12-09

    Refraction and deflection of shear zones in layered granular materials was studied experimentally and numerically. We show, that (i) according to a recent theoretical prediction [T. Unger, Phys. Rev. Lett. 98, 018301 (2007)] shear zones refract in layered systems in analogy with light refraction, (ii) zone refraction obeys Snell's law known from geometric optics and (iii) under natural pressure conditions (i.e. in the presence of gravity) the zone can also be deflected by the interface so that the deformation of the high friction material is avoided.

  3. Resonant alignment of microswimmer trajectories in oscillatory shear flows

    E-Print Network [OSTI]

    Alexander Hope; Ottavio A. Croze; Wilson C. K. Poon; Martin A. Bees; Mark D. Haw

    2015-07-26

    Oscillatory flows are common in the environment, industrial applications and rheological investigations. We experimentally characterise the response of the alga {\\it Dunaliella salina} to oscillatory shear and squeeze flows, and report the surprising discovery that algal swimming trajectories orient perpendicular to the flow-shear plane. The ordering has the characteristics of a resonance in the driving parameter space, which is qualitatively reproduced by a model accounting for helical swimming. Our discovery challenges current understanding of swimmers in flows and provides the foundations for the oscillatory rheology of active suspensions, of particular relevance to algal processing applications.

  4. Resonant alignment of microswimmer trajectories in oscillatory shear flows

    E-Print Network [OSTI]

    Hope, Alexander; Poon, Wilson C K; Bees, Martin A; Haw, Mark D

    2015-01-01

    Oscillatory flows are common in the environment, industrial applications and rheological investigations. We experimentally characterise the response of the alga {\\it Dunaliella salina} to oscillatory shear and squeeze flows, and report the surprising discovery that algal swimming trajectories orient perpendicular to the flow-shear plane. The ordering has the characteristics of a resonance in the driving parameter space, which is qualitatively reproduced by a model accounting for helical swimming. Our discovery challenges current understanding of swimmers in flows and provides the foundations for the oscillatory rheology of active suspensions, of particular relevance to algal processing applications.

  5. Shear Flow instability in a strongly coupled dusty plasma

    E-Print Network [OSTI]

    Banerjee, D; Chakrabarti, N

    2013-01-01

    Linear stability analysis of strongly coupled incompressible dusty plasma in presence of shear flow has been carried out using Generalized Hydrodynamical(GH) model. With the proper Galilean invariant GH model, a nonlocal eigenvalue analysis has been done using different velocity profiles. It is shown that the effect of elasticity enhances the growth rate of shear flow driven Kelvin- Helmholtz (KH) instability. The interplay between viscosity and elasticity not only enhances the growth rate but the spatial domain of the instability is also widened. The growth rate in various parameter space and the corresponding eigen functions are presented.

  6. Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch

    E-Print Network [OSTI]

    Winterberg, F

    2008-01-01

    Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition method with isentropic compression then in a z-pinch where the entire plasma column is heated.

  7. Arrest stress of uniformly sheared wet granular matter

    E-Print Network [OSTI]

    S. H. Ebrahimnazhad Rahbari; M. Brinkmann; J. Vollmer

    2015-06-21

    We conduct extensive independent numerical experiments considering frictionless disks without internal degrees of freedom (rotation etc.) in two dimensions. We report here that for a large range of the packing fractions below random-close packing, all components of the stress tensor of wet granular materials remain finite in the limit of zero shear rate. This is direct evidence for a fluid-to-solid arrest transition. The offset value of the shear stress characterizes plastic deformation of the arrested state {which corresponds to {\\em dynamic yield stress} of the system}. {Based on an analytical line of argument, we propose that the mean number of capillary bridges per particle, $\

  8. Nonlinear FE analysis of cracks in tension and shear

    E-Print Network [OSTI]

    Kesse, G.; Lees, Janet M.

    2007-05-01

    . In combination with Fig. 17, which 70 Load step Shear displacement stage Normal displacement stage ?6 ?5 ?4 ?3 ?2 ?1 0 1 2 3 1 4 7 10 13 16 19 22 25 28 3 1 34 37 40 43 46 49 52 55 58 6 1 64 67 S tre ss : N /m m 2 NL Beta Fig. 13. Comparison of normal stress... enhancement of concrete. ASCE Journal of Composites for Construction, 2002, 6, No. 4, 249–256. 2. Kesse G. Concrete Beams with External Prestressed Carbon FRP Shear Reinforcement. PhD thesis, University of Cambridge, UK, 2003. 3. Bazant Z. P. and Planas J...

  9. Shear Strength Prediction By Modified Plasticity Theory For SFRC Beams

    SciTech Connect (OSTI)

    Colajanni, Piero; Recupero, Antonino; Spinella, Nino [Dipartimento di Ingegneria Civile, Universita di Messina, C.da di Dio 1-98166, Vill. S. Agata, Messina (Italy)

    2008-07-08

    the plastic Crack Sliding Model (CSM) is extended for derivation of a physical model for the prediction of ultimate shear strength of SFRC beams, by assuming that the critical cracks is modeled by a yield lines. To this aim, the CSM is improved in order to take into account the strength increases due to the arch effect for deep beam. Then, the effectiveness factors for the concrete under biaxial stress are calibrated for fibrous concrete. The proposed model, able to provide the shear strength and the position of the critical cracks, is validate by a large set of test results collected in literature.

  10. EMISSIONS REDUCTIONS USING HYDROGEN FROM PLASMATRON FUEL CONVERTERS

    SciTech Connect (OSTI)

    Bromberg, L

    2000-08-20

    Substantial progress in engine emission control is needed in order to meet present and proposed regulations for both spark ignition and diesel engines. Tightening regulations throughout the world reflect the ongoing concern with vehicle emissions. Recently developed compact plasmatron fuel converters have features that are suitable for onboard production of hydrogen for both fuel pretreatment and for exhaust aftertreatment applications. Systems that make use of these devices in conjunction with aftertreatment catalysts have the potential to improve significantly prospects for reduction of diesel engine emissions. Plasmatron fuel converters can provide a rapid response compact means to transform efficiently a wide range of hydrocarbon fuels into hydrogen rich gas. They have been used to reform natural gas [Bromberg1], gasoline [Green], diesel [Bromberg2] and hard-to-reform biofuels [Cohn1] into hydrogen rich gas (H2 + CO). The development of these devices has been pursued for the purpose of reducing engine exhaust pollutants by providing hydrogen rich gas for combustion in spark ignition and possibly diesel engines, as shown in Figure 1 [Cohn2]. Recent developments in compact plasmatron reformer design at MIT have resulted in substantial decreases in electrical power requirements. These new developments also increase the lifetime of the electrodes.

  11. Converting Maturing Nuclear Sites to Integrated Power Production Islands

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

    Solbrig, Charles W.

    2011-01-01

    Nuclear islands, which are integrated power production sites, could effectively sequester and safeguard the US stockpile of plutonium. A nuclear island, an evolution of the integral fast reactor, utilizes all the Transuranics (Pu plus minor actinides) produced in power production, and it eliminates all spent fuel shipments to and from the site. This latter attribute requires that fuel reprocessing occur on each site and that fast reactors be built on-site to utilize the TRU. All commercial spent fuel shipments could be eliminated by converting all LWR nuclear power sites to nuclear islands. Existing LWR sites have the added advantage ofmore »already possessing a license to produce nuclear power. Each could contribute to an increase in the nuclear power production by adding one or more fast reactors. Both the TRU and the depleted uranium obtained in reprocessing would be used on-site for fast fuel manufacture. Only fission products would be shipped to a repository for storage. The nuclear island concept could be used to alleviate the strain of LWR plant sites currently approaching or exceeding their spent fuel pool storage capacity. Fast reactor breeding ratio could be designed to convert existing sites to all fast reactors, or keep the majority thermal.« less

  12. Triple voltage dc-to-dc converter and method

    DOE Patents [OSTI]

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05

    A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

  13. Enhanced thermal and gas flow performance in a three-way catalytic converter through use of insulation within the ceramic monolith

    Broader source: Energy.gov [DOE]

    Emissions performance comparison of conventional catalytic converter with multi-channel catalytic converter (ceramic fiber insulation layers introduced into ceramic monolith of three-way catalytic converter)

  14. Numerical Study of Acoustic Modes in Ducted Shear Flow

    E-Print Network [OSTI]

    Rienstra, Sjoerd W.

    Numerical Study of Acoustic Modes in Ducted Shear Flow Gregory G. Vilenski & Sjoerd W. Rienstra mean flow inside a duct is studied numerically. For isentropic flow in a circular duct with zero swirl 26, 2007 #12;1 Introduction Normal mode analysis of small-amplitude disturbances in an annular duct

  15. Shear Viscosity to Entropy within a Parton Cascade

    E-Print Network [OSTI]

    A. El; C. Greiner; Z. Xu

    2007-06-28

    The shear viscosity is calculated by means of the perturbative kinetic partonic cascade BAMPS with CGC initial conditons for various saturation momentum scale Q_s. eta/s ~ 0.15 stays approximately constant when going from RHIC to LHC.

  16. Internal Wave Reflection in Uniform Shear B. R. Sutherland ?

    E-Print Network [OSTI]

    Sutherland, Bruce

    Internal Wave Reflection in Uniform Shear B. R. Sutherland ? Department of Mathematical Sciences, University of Alberta Edmonton, AB T6G 2G1, Canada SUMMARY If non­hydrostatic internal waves are of sufficiently large amplitude, they undergo significant dispersion due to interactions between the waves

  17. BIAS-FREE SHEAR ESTIMATION USING ARTIFICIAL NEURAL NETWORKS

    SciTech Connect (OSTI)

    Gruen, D.; Seitz, S.; Koppenhoefer, J.; Riffeser, A., E-mail: dgruen@usm.uni-muenchen.d [University Observatory Munich, Scheinerstrasse 1, 81679 Muenchen (Germany)

    2010-09-01

    Bias due to imperfect shear calibration is the biggest obstacle when constraints on cosmological parameters are to be extracted from large area weak lensing surveys such as Pan-STARRS-3{pi}, DES, or future satellite missions like EUCLID. We demonstrate that bias present in existing shear measurement pipelines (e.g., KSB) can be almost entirely removed by means of neural networks. In this way, bias correction can depend on the properties of the individual galaxy instead of being a single global value. We present a procedure to train neural networks for shear estimation and apply this to subsets of simulated GREAT08 RealNoise data. We also show that circularization of the point-spread function (PSF) before measuring the shear reduces the scatter related to the PSF anisotropy correction and thus leads to improved measurements, particularly on low and medium signal-to-noise data. Our results are competitive with the best performers in the GREAT08 competition, especially for the medium and higher signal-to-noise sets. Expressed in terms of the quality parameter defined by GREAT08, we achieve a Q{approx} 40, 140, and 1300 without and 50, 200, and 1300 with circularization for low, medium, and high signal-to-noise data sets, respectively.

  18. Active, polymer-based composite material implementing simple shear 

    E-Print Network [OSTI]

    Lee, Sang Jin

    2009-05-15

    , Dr. Terry S. Creasy. vi ACKNOWLEDGEMENTS This material is based upon work supported by DARPA and the U.S. Army Research, Development and Engineering Command under contract W911 W6-04-C... of Shear Actuator .................................................................46 3.3.1 Mold design and CNC machining.............................................47 3.3.2 Assembly...

  19. CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR

    E-Print Network [OSTI]

    CONTAINED PLASTIC DEFORMATION NEAR CRACKS AND NOTCHES UNDER LONGITUDINAL SHEAR James R. Rice* ABSTRACT An exact linear elastic-perfectly plastic solution is presented for the problem of a sharp notch coordinates corresponding to given stresses, position of the elastic-plastic boundary, and accompanying

  20. Shear modulus and Dilatancy Softening in Granular Packings above Jamming

    E-Print Network [OSTI]

    Corentin Coulais; Antoine Seguin; Olivier Dauchot

    2014-11-07

    We investigate experimentally the mechanical response of a monolayer of bi-disperse frictional grains to an inhomogeneous shear perturbation across the jamming transition. We inflate an intruder inside the packing and use photo-elasticity and tracking techniques to measure the induced shear strain and stresses at the grain scale. We quantify experimentally the constitutive relations for strain amplitudes as low as 0.001 and for a range of packing fractions within 2% variation around the jamming transition. At the transition strong nonlinear effects set in : both the shear modulus and the dilatancy shear-soften at small strain until a critical strain is reached where effective linearity is recovered. The dependencies of the critical strain and the associated critical stresses on the distance from jamming are extracted via scaling analysis. We check that the constitutive laws, when applied to the equations governing mechanical equilibrium, lead to the observed stress and strain profiles. These profiles exhibit a spatial crossover between an effective linear regime close to the inflater and the truly nonlinear regime away from it. The crossover length diverges at the jamming transition.

  1. Precursors to the shear failure of rock discontinuities

    E-Print Network [OSTI]

    Pyrak-Nolte, Laura J.

    process. Ultrasonic precursors were identified as distinct maxima in the amplitude of transmitted shear of seismic velocities and seismic wave attenuation [Aggarwal et al., 1973; Lockner et al., 1977; Chen et al has been successfully used in laboratory experiments to provide insights into deformation processes

  2. Rock dilation, nonlinear deformation, and pore pressure change under shear

    E-Print Network [OSTI]

    Lyakhovsky, Vladimir

    Rock dilation, nonlinear deformation, and pore pressure change under shear Yariv Hamiel a criterion and pore pressure response to a fault slip. We investigate the poroelastic response of two an increase of pore pressure with mean stress (according to Skempton coefficient B) under undrained conditions

  3. Efficiency of Mixing Forced by Unsteady Shear Flow RYUICHIRO INOUE

    E-Print Network [OSTI]

    Smyth, William David

    Efficiency of Mixing Forced by Unsteady Shear Flow RYUICHIRO INOUE Department of Physics form 18 December 2008) ABSTRACT The dependence of mixing efficiency on time-varying forcing is studied frame and allowing the tilt angle to vary in time. Mixing efficiency Gc is defined as the ratio

  4. Transition to Turbulence in Shear-Thinning Fluids 

    E-Print Network [OSTI]

    Zhen, Ni

    2014-04-23

    In this dissertation, the effects of a shear-thinning fluid on the evolution of a hairpin vortex are investigated. The fluid viscosity is determined using a power law model and direct numerical simulations are performed using a pseudo-spectral code...

  5. Large amplitude oscillatory shear of pseudoplastic and elastoviscoplastic materials

    E-Print Network [OSTI]

    , a pseudoplastic shear-thinning xanthan gum solution and an elastoviscoplastic invert-emulsion drilling fluid to achieve particular performance with complex fluids. For example, oilfield drilling fluids are often formulated to be yield stress fluids to meet the needs of an intermittent drilling process. While drilling

  6. Strategic Control of Transverse Jet Shear Layer Instabilities J. Davitian,

    E-Print Network [OSTI]

    M'Closkey, Robert T.

    engines, dilution jet injection in gas turbine combustors, thrust vectoring jets, and turbine blade filmStrategic Control of Transverse Jet Shear Layer Instabilities J. Davitian, C. Hendrickson, D jet in crossflow or transverse jet. Jet nozzles that are flush as well as elevated with respect

  7. Multi-Scale Investigation of Sheared Flows In Magnetized Plasmas

    SciTech Connect (OSTI)

    Edward, Jr., Thomas

    2014-09-19

    Flows parallel and perpendicular to magnetic fields in a plasma are important phenomena in many areas of plasma science research. The presence of these spatially inhomogeneous flows is often associated with the stability of the plasma. In fusion plasmas, these sheared flows can be stabilizing while in space plasmas, these sheared flows can be destabilizing. Because of this, there is broad interest in understanding the coupling between plasma stability and plasma flows. This research project has engaged in a study of the plasma response to spatially inhomogeneous plasma flows using three different experimental devices: the Auburn Linear Experiment for Instability Studies (ALEXIS) and the Compact Toroidal Hybrid (CTH) stellarator devices at Auburn University, and the Space Plasma Simulation Chamber (SPSC) at the Naval Research Laboratory. This work has shown that there is a commonality of the plasma response to sheared flows across a wide range of plasma parameters and magnetic field geometries. The goal of this multi-device, multi-scale project is to understand how sheared flows established by the same underlying physical mechanisms lead to different plasma responses in fusion, laboratory, and space plasmas.

  8. Density-shear instability in electron magneto-hydrodynamics

    SciTech Connect (OSTI)

    Wood, T. S. Hollerbach, R.; Lyutikov, M.

    2014-05-15

    We discuss a novel instability in inertia-less electron magneto-hydrodynamics (EMHD), which arises from a combination of electron velocity shear and electron density gradients. The unstable modes have a lengthscale longer than the transverse density scale, and a growth-rate of the order of the inverse Hall timescale. We suggest that this density-shear instability may be of importance in magnetic reconnection regions on scales smaller than the ion skin depth, and in neutron star crusts. We demonstrate that the so-called Hall drift instability, previously argued to be relevant in neutron star crusts, is a resistive tearing instability rather than an instability of the Hall term itself. We argue that the density-shear instability is of greater significance in neutron stars than the tearing instability, because it generally has a faster growth-rate and is less sensitive to geometry and boundary conditions. We prove that, for uniform electron density, EMHD is “at least as stable” as regular, incompressible MHD, in the sense that any field configuration that is stable in MHD is also stable in EMHD. We present a connection between the density-shear instability in EMHD and the magneto-buoyancy instability in anelastic MHD.

  9. The Effects of Realistic Geological Heterogeneity on Seismic Modeling: Applications in Shear Wave Generation and Near-Surface Tunnel Detection

    E-Print Network [OSTI]

    Sherman, Christopher Scott

    2014-01-01

    5.1.1 Shear Wave Generation . . . . . 5.1.2 Near SurfaceApplications in Shear Wave Generation and Near-SurfaceApplications in Shear Wave Generation and Near-Surface

  10. Active Vibration Suppression of Sandwich Beams using Piezoelectric Shear Actuators: Experiments and

    E-Print Network [OSTI]

    Vel, Senthil

    Active Vibration Suppression of Sandwich Beams using Piezoelectric Shear Actuators: Experiments assessment of the vibration suppression of smart structures using piezoelectric shear actuators. Experimental of the sandwich beam. Active vibration suppression is achieved using either positive position feedback or strain

  11. Magnetic Field Generation and Particle Energization at Relativistic Shear Boundaries in Collisionless Electron-Positron Plasmas

    E-Print Network [OSTI]

    Boettcher, Markus

    1 Magnetic Field Generation and Particle Energization at Relativistic Shear Boundaries. We find efficient magnetic field generation and particle energization at the shear boundary, driven generation (Colgate et al 2001, Medvedev & Loeb 1999) and nonthermal particle energization (Berezhko 1981

  12. Estimation of the bed shear stress in vegetated and bare channels

    E-Print Network [OSTI]

    Yang, Qingjun (Judy Qingjun)

    2015-01-01

    The shear stress at the bed of a channel influences important benthic processes such as sediment transport. Several methods exist to estimate the bed shear stress in bare channels without vegetation, but most of these are ...

  13. Damage to HDPE geomembrane from interface shear over gravelly compacted clay liner

    E-Print Network [OSTI]

    Thielmann, Stuart

    2012-01-01

    R. S. (2011). “Geomembrane damage due to static and cyclic66 Figure 4.10. GM damage results after shearing for Testsshear displacement on shear strength and GM damage for test

  14. Investigation of shear banding in three-dimensional foams G. Ovarlez1

    E-Print Network [OSTI]

    stress, this leads to the viscosity bifurcation phenomenon [8,9]. This implies that, in addition) and shear-induced resuspension [11]. Some yield stress fluids seem not to exhibit shear banding, although

  15. Silicon micromachined sensors and sensor arrays for shear-stress measurements in aerodynamic flows

    E-Print Network [OSTI]

    Padmanabhan, Aravind

    In this thesis we report on a new micromachined floating-element shear-stress sensor for turbulent boundary layer research. Applications in low shear-stress environments such as turbulent boundary layers require extremely ...

  16. Analysis of Bolt and Rivet Structural Fasteners Subjected to Dynamic and Quasi-Static Shear Loadings 

    E-Print Network [OSTI]

    Rabalais, Christopher Paul

    2015-05-07

    Non-pretensioned bolted, pretensioned bolted, and riveted lap-spliced specimens were tested to observe how the fasteners’ shear strengths were affected by (1) loading type, (2) fastener type, (3) number of shear planes, ...

  17. Apparatuses and method for converting electromagnetic radiation to direct current

    DOE Patents [OSTI]

    Kotter, Dale K; Novack, Steven D

    2014-09-30

    An energy conversion device may include a first antenna and a second antenna configured to generate an AC current responsive to incident radiation, at least one stripline, and a rectifier coupled with the at least one stripline along a length of the at least one stripline. An energy conversion device may also include an array of nanoantennas configured to generate an AC current in response to receiving incident radiation. Each nanoantenna of the array includes a pair of resonant elements, and a shared rectifier operably coupled to the pair of resonant elements, the shared rectifier configured to convert the AC current to a DC current. The energy conversion device may further include a bus structure operably coupled with the array of nanoantennas and configured to receive the DC current from the array of nanoantennas and transmit the DC current away from the array of nanoantennas.

  18. Low Head, Vortex Induced Vibrations River Energy Converter

    SciTech Connect (OSTI)

    Bernitsas, Michael B.; Dritz, Tad

    2006-06-30

    Vortex Induced Vibrations Aquatic Clean Energy (VIVACE) is a novel, demonstrated approach to extracting energy from water currents. This invention is based on a phenomenon called Vortex Induced Vibrations (VIV), which was first observed by Leonardo da Vinci in 1504AD. He called it ‘Aeolian Tones.’ For decades, engineers have attempted to prevent this type of vibration from damaging structures, such as offshore platforms, nuclear fuel rods, cables, buildings, and bridges. The underlying concept of the VIVACE Converter is the following: Strengthen rather than spoil vortex shedding; enhance rather than suppress VIV; harness rather than mitigate VIV energy. By maximizing and utilizing this unique phenomenon, VIVACE takes this “problem” and successfully transforms it into a valuable resource for mankind.

  19. A Study of Radiative Bottomonium Transitions using Converted Photons

    SciTech Connect (OSTI)

    Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-15

    The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.

  20. Utilizing zero-sequence switchings for reversible converters

    DOE Patents [OSTI]

    Hsu, John S.; Su, Gui-Jia; Adams, Donald J.; Nagashima, James M.; Stancu, Constantin; Carlson, Douglas S.; Smith, Gregory S.

    2004-12-14

    A method for providing additional dc inputs or outputs (49, 59) from a dc-to-ac inverter (10) for controlling motor loads (60) comprises deriving zero-sequence components (V.sub.ao, V.sub.bo, and V.sub.co) from the inverter (10) through additional circuit branches with power switching devices (23, 44, 46), transforming the voltage between a high voltage and a low voltage using a transformer or motor (42, 50), converting the low voltage between ac and dc using a rectifier (41, 51) or an H-bridge (61), and providing at least one low voltage dc input or output (49, 59). The transformation of the ac voltage may be either single phase or three phase. Where less than a 100% duty cycle is acceptable, a two-phase modulation of the switching signals controlling the inverter (10) reduces switching losses in the inverter (10). A plurality of circuits for carrying out the invention are also disclosed.

  1. The Force of a Tsunami on a Wave Energy Converter

    E-Print Network [OSTI]

    O'Brien, Laura; Renzi, Emiliano; Dutykh, Denys; Dias, Frédéric

    2012-01-01

    With an increasing emphasis on renewable energy resources, wave power technology is fast becoming a realistic solution. However, the recent tsunami in Japan was a harsh reminder of the ferocity of the ocean. It is known that tsunamis are nearly undetectable in the open ocean but as the wave approaches the shore its energy is compressed creating large destructive waves. The question posed here is whether a nearshore wave energy converter (WEC) could withstand the force of an incoming tsunami. The analytical 3D model of Renzi & Dias (2012) developed within the framework of a linear theory and applied to an array of fixed plates is used. The time derivative of the velocity potential allows the hydrodynamic force to be calculated.

  2. Performance of Mismatched PV Systems With Submodule Integrated Converters

    SciTech Connect (OSTI)

    Olalla, C; Deline, C; Maksimovic, D

    2014-01-01

    Mismatch power losses in photovoltaic (PV) systems can be reduced by the use of distributed power electronics at the module or submodule level. This paper presents an experimentally validated numerical model that can be used to predict power production with distributed maximum power point tracking (DMPPT) down to the cell level. The model allows the investigations of different DMPPT architectures, as well as the impact of conversion efficiencies and power constraints. Results are presented for annual simulations of three representative partial shading scenarios and two scenarios where mismatches are due to aging over a period of 25 years. It is shown that DMPPT solutions that are based on submodule integrated converters offer 6.9-11.1% improvements in annual energy yield relative to a baseline centralized MPPT scenario.

  3. NREL Research on Converting Biomass to Liquid Fuels

    ScienceCinema (OSTI)

    None

    2013-05-29

    Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called "biofuels," to help meet transportation fuel needs. The two most common types of biofuels are ethanol and biodiesel. Today, ethanol is made from starches and sugars, but at the National Renewable Energy Laboratory (NREL) scientists are developing technology to allow it to be made from cellulose and hemicellulose, the fibrous material that makes up the bulk of most plant matter. Biodiesel is made by combining alcohol (usually methanol) with vegetable oil, animal fat, or recycled cooking grease. It can be used as an additive (typically 20%) to reduce vehicle emissions or in its pure form as a renewable alternative fuel for diesel engines. For a text version of this video visit http://www.nrel.gov/learning/re_biofuels.html

  4. Reference Model 6 (RM6): Oscillating Wave Energy Converter.

    SciTech Connect (OSTI)

    Bull, Diana L; Smith, Chris; Jenne, Dale Scott; Jacob, Paul; Copping, Andrea; Willits, Steve; Fontaine, Arnold; Brefort, Dorian; Gordon, Margaret Ellen; Copeland, Robert; Jepsen, Richard A.

    2014-10-01

    This report is an addendum to SAND2013-9040: Methodology for Design and Economic Analysis of Marine Energy Conversion (MEC) Technologies. This report describes an Oscillating Water Column Wave Energy Converter reference model design in a complementary manner to Reference Models 1-4 contained in the above report. In this report, a conceptual design for an Oscillating Water Column Wave Energy Converter (WEC) device appropriate for the modeled reference resource site was identified, and a detailed backward bent duct buoy (BBDB) device design was developed using a combination of numerical modeling tools and scaled physical models. Our team used the methodology in SAND2013-9040 for the economic analysis that included costs for designing, manufacturing, deploying, and operating commercial-scale MEC arrays, up to 100 devices. The methodology was applied to identify key cost drivers and to estimate levelized cost of energy (LCOE) for this RM6 Oscillating Water Column device in dollars per kilowatt-hour (%24/kWh). Although many costs were difficult to estimate at this time due to the lack of operational experience, the main contribution of this work was to disseminate a detailed set of methodologies and models that allow for an initial cost analysis of this emerging technology. This project is sponsored by the U.S. Department of Energy's (DOE) Wind and Water Power Technologies Program Office (WWPTO), within the Office of Energy Efficiency & Renewable Energy (EERE). Sandia National Laboratories, the lead in this effort, collaborated with partners from National Laboratories, industry, and universities to design and test this reference model.

  5. Reference Model 5 (RM5): Oscillating Surge Wave Energy Converter

    SciTech Connect (OSTI)

    Yu, Y. H.; Jenne, D. S.; Thresher, R.; Copping, A.; Geerlofs, S.; Hanna, L. A.

    2015-01-01

    This report is an addendum to SAND2013-9040: Methodology for Design and Economic Analysis of Marine Energy Conversion (MEC) Technologies. This report describes an Oscillating Water Column Wave Energy Converter (OSWEC) reference model design in a complementary manner to Reference Models 1-4 contained in the above report. A conceptual design for a taut moored oscillating surge wave energy converter was developed. The design had an annual electrical power of 108 kilowatts (kW), rated power of 360 kW, and intended deployment at water depths between 50 m and 100 m. The study includes structural analysis, power output estimation, a hydraulic power conversion chain system, and mooring designs. The results were used to estimate device capital cost and annual operation and maintenance costs. The device performance and costs were used for the economic analysis, following the methodology presented in SAND2013-9040 that included costs for designing, manufacturing, deploying, and operating commercial-scale MEC arrays up to 100 devices. The levelized cost of energy estimated for the Reference Model 5 OSWEC, presented in this report, was for a single device and arrays of 10, 50, and 100 units, and it enabled the economic analysis to account for cost reductions associated with economies of scale. The baseline commercial levelized cost of energy estimate for the Reference Model 5 device in an array comprised of 10 units is $1.44/kilowatt-hour (kWh), and the value drops to approximately $0.69/kWh for an array of 100 units.

  6. Constitutive Model for Material Comminuting at High Shear Rate

    E-Print Network [OSTI]

    Zdenek P. Bazant; Ferhun C. Caner

    2013-06-04

    The modeling of high velocity impact into brittle or quasibrittle solids is hampered by the unavailability of a constitutive model capturing the effects of material comminution into very fine particles. The present objective is to develop such a model, usable in finite element programs. The comminution at very high strain rates can dissipate a large portion of the kinetic energy of an impacting missile. The spatial derivative of the energy dissipated by comminution gives a force resisting the penetration, which is superposed on the nodal forces obtained from the static constitutive model in a finite element program. The present theory is inspired partly by Grady's model for comminution due to explosion inside a hollow sphere, and partly by analogy with turbulence. In high velocity turbulent flow, the energy dissipation rate is enhanced by the formation of micro-vortices (eddies) which dissipate energy by viscous shear stress. Similarly, here it is assumed that the energy dissipation at fast deformation of a confined solid gets enhanced by the release of kinetic energy of the motion associated with a high-rate shear strain of forming particles. For simplicity, the shape of these particles in the plane of maximum shear rate is considered to be regular hexagons. The rate of release of free energy density consisting of the sum of this energy and the fracture energy of the interface between the forming particle is minimized. The particle sizes are assumed to be distributed according to Schuhmann's power law. It is concluded that the minimum particle size is inversely proportional to the (2/3)-power of the shear strain rate, that the kinetic energy release is to proportional to the (2/3)-power, and that the dynamic comminution creates an apparent material viscosity inversely proportional to the (1/3)-power of the shear strain rate.

  7. Mechanical properties of jammed packings of frictionless spheres under applied shear stress

    E-Print Network [OSTI]

    Hao Liu; Hua Tong; Ning Xu

    2015-02-03

    By minimizing a thermodynamic-like potential, we unbiasedly sample the potential energy landscape of soft and frictionless spheres under constant shear stress. We obtain zero-temperature jammed states under desired shear stresses and investigate their mechanical properties as a function of the shear stress. As a comparison, we also obtain jammed states from the quasistatic-shear sampling in which the shear stress is not well-controlled. Although the yield stresses determined by both samplings show the same power-law scaling with the compression from point $J$, i.e.~the jamming transition point at zero temperature and shear stress, for finite size systems, the quasistatic-shear sampling leads to a lower yield stress and a higher critical volume fraction of point $J$. The shear modulus of jammed solids decreases when increasing the shear stress. However, the shear modulus does not decay to zero at yielding. This discontinuous change of the shear modulus implies the discontinuous nature of the unjamming transition under nonzero shear stress, which is further verified by the observation of a discontinuous jump of the pressure from jammed solids to shear flows. The pressure jump decreases upon decompression and approaches zero at the critical-like point $J$, in analogy with well-known phase transitions under external field. The analysis of force networks in jammed solids reveals that the force distribution is more sensitive to the increase of the shear stress near point $J$. The force network anisotropy increases with the shear stress. Weak particle contacts near the average force and under large shear stresses exhibit asymmetric angle distribution.

  8. SHEAR WAVE TIME-LAPSE SEISMIC MONITORING OF A TIGHT GAS SANDSTONE RESERVOIR, RULISON FIELD, COLORADO

    E-Print Network [OSTI]

    SHEAR WAVE TIME-LAPSE SEISMIC MONITORING OF A TIGHT GAS SANDSTONE RESERVOIR, RULISON FIELD focused specifically on the use of time-lapse (4D) poststack migrated shear-wave seismic data of shear wave data as a tool for monitoring 4D changes. The basin centered tight gas sandstone reservoir

  9. Three-dimensionality of sand ripples under steady laminar shear flow

    E-Print Network [OSTI]

    Three-dimensionality of sand ripples under steady laminar shear flow V. Langlois and A. Valance laminar shear flow using a process-based stability approach. The hydrodynamics of the problem is solved under steady laminar shear flow, J. Geophys. Res., 110, F04S09, doi:10.1029/2004JF000278. 1

  10. Effect of subharmonic forcing on transition in chemically reactive shear-layers

    E-Print Network [OSTI]

    Texas at Arlington, University of

    scale mixing in cavity stabilized supersonic combustors,3 where shear-layers are formed between the air transition. Supersonic shear-layers form in the windward region of the vehicles due to shock-shock inter to the supersonic shear layer modes discovered by Jackson and Grosch7 because they originate when the compressible

  11. VOLUME 18, NUMBER 2, 2010 n LINCOLN LABORATORY JOURNAL 47 Wind-Shear System

    E-Print Network [OSTI]

    Cho, John Y. N.

    VOLUME 18, NUMBER 2, 2010 n LINCOLN LABORATORY JOURNAL 47 Wind-Shear System Cost-Benefit Analysis. » #12;48 LINCOLN LABORATORY JOURNAL n VOLUME 18, NUMBER 2, 2010 WIND-SHEAR SYSTEM COST-BENEFIT ANALYSIS-shear system cost benefits in order to retrospectively evaluate the expected safety benefits of wind

  12. Geosynthetics International, 2004, 11, No. 3 State-of-the-art report: GCL shear strength and

    E-Print Network [OSTI]

    ­ displacement behavior and shear strength interpretation are presented, including long-term performance issues (GCLs) are needed for static and seismic stability analyses in the design of waste containment of GCLs. Essential concepts of shear stress­displacement behavior and shear strength interpretation

  13. Reflective Cracking Study: First-level Report on Laboratory Shear Testing

    E-Print Network [OSTI]

    Tsai, Bor-Wen; Jones, David; Harvey, John T; Monismith, Carl L.; Guada, I.; Signore, J,

    2008-01-01

    2 and ? 2 ln? 3 and ? 3 lnG lnkcy5 lnn 1 lnn 2 lnNf lnpct559 Figure 4.28: Residual plots of LnG. (Pooled ShearResilient Shear Modulus, G* (lng) The Resilient Shear

  14. Direct dating of left-lateral deformation along the Red River shear zone, China and Vietnam

    E-Print Network [OSTI]

    Direct dating of left-lateral deformation along the Red River shear zone, China and Vietnam Lisa D-lateral shearing. Data from the southern RRSZ within Vietnam are complicated by Tertiary overprinting of rocks dating of left-lateral deformation along the Red River shear zone, China and Vietnam, J. Geophys. Res

  15. Detection Probability Modeling for Airport Wind-Shear August 28, 2008

    E-Print Network [OSTI]

    Cho, John Y. N.

    Detection Probability Modeling for Airport Wind-Shear Sensors August 28, 2008 John Y. N. Cho Robert An objective wind-shear detection probability estimation model is developed for radar, lidar, and sensor combinations. The model includes effects of system sensitivity, site-specific wind-shear, clutter, and terrain

  16. Shear-Stress-Mediated Refolding of Proteins from Aggregates and Inclusion Bodies

    E-Print Network [OSTI]

    Weiss, Gregory A.

    Shear-Stress-Mediated Refolding of Proteins from Aggregates and Inclusion Bodies Tom Z. Yuan and misfolded proteins directed to inclusion bodies. We report the application of shear stress in micrometer by applying finely controlled levels of shear stress to refold proteins trapped in inclusion bodies

  17. Shear Stress in Smooth Rectangular Open-Channel Flows and Pierre Y. Julien2

    E-Print Network [OSTI]

    Julien, Pierre Y.

    Shear Stress in Smooth Rectangular Open-Channel Flows Junke Guo1 and Pierre Y. Julien2 Abstract: The average bed and sidewall shear stresses in smooth rectangular open-channel flows are determined after solving the continuity and momentum equations. The analysis shows that the shear stresses are function

  18. Shear band in sand with spatially varying density Ronaldo I. Borja a,n

    E-Print Network [OSTI]

    Borja, Ronaldo I.

    Shear band in sand with spatially varying density Ronaldo I. Borja a,n , Xiaoyu Song a , Amy L Keywords: Bifurcation Digital Image Correlation Heterogeneous sand Shear band Strain localization a b s t r for the selection of the persistent shear band in a symmetrically loaded localizing sand body. We combine

  19. Relaxation back to equilibrium after cessation of shear for confined colloidal bilayers

    E-Print Network [OSTI]

    René Messina; Hartmut Löwen

    2005-06-24

    Crystalline bilayers of charged colloidal suspensions which are confined between two parallel plates and sheared via a relative motion of the two plates are studied by extensive Brownian dynamics computer simulations. The charge-stabilized suspension is modeled by a Yukawa pair potential. The unsheared equilibrium configuration are two crystalline layers with a nested quadratic in-plane structure. For increasing shear rates $\\dot \\gamma$, we find the following steady states: first, there is a static solid which is elastically sheared until a yield-stress limit is reached. Then there are two crystalline layers sliding on top of each other with a registration procedure. Higher shear rates melt the crystalline bilayers and even higher shear rates lead to a reentrant solid stratified in the shear direction. This qualitative scenario is similar to that found in previous bulk simulations. We have then studied the relaxation of the sheared steady state back to equilibrium after an instantaneous cessation of shear and found a nonmonotonic behavior of the typical relaxation time as a function of the shear rate $\\dot \\gamma$. In particular, application of high shear rates accelerates the relaxation back to equilibrium since shear-ordering facilitates the growth of the equilibrium crystal. This mechanism can be used to grow defect-free colloidal crystals from strongly sheared suspensions. Our theoretical predictions can be verified in real-space experiments of strongly confined charged suspensions.

  20. 1654 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 24, NO. 6, JUNE 2009 Very-High-Frequency Resonant Boost Converters

    E-Print Network [OSTI]

    Perreault, Dave

    Boost Converters Robert C. N. Pilawa-Podgurski, Student Member, IEEE, Anthony D. Sagneri, Student Member amplifier, class- inverter, harmonic peaking, resonant boost converter, resonant dc­ dc converter, resonant.2016098 Fig. 1. Schematic of the proposed resonant boost converter topology. [6]­[8], and [10], it is often

  1. A Virtual DSP System for Design Instruction of Power Converters AA.. KKeeyyhhaannii aanndd MM.. NN.. MMaarrwwaallii GGeerraalldd BBaauummggaarrttnneerr

    E-Print Network [OSTI]

    Baumgartner, Gerald

    1 A Virtual DSP System for Design Instruction of Power Converters AA.. KKeeyyhhaannii aanndd MM the development of an object oriented DSP based for design and control of power converters. The testbed `hard' switching power converters, a resonant converter utilizes a controlled series or parallel LC

  2. An Integrated Onboard Charger and Accessary Power Converter for Plug-in Electric Vehicles

    SciTech Connect (OSTI)

    Su, Gui-Jia; Tang, Lixin

    2013-01-01

    Abstract: In this paper, an integrated onboard battery charger and accessary dc-dc converter for plug-in electric vehicles (PEVs) is presented. The idea is to utilize the already available traction drive inverters and motors of a PEV as the frond converter of the charger circuit and the transformer of the 14 V accessary dc-dc converter to provide galvanic isolation. The topology was verified by modeling and experimental results on a 5 kW charger prototype

  3. Characterization of U.S. Wave Energy Converter Test Sites: A...

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

    data and wave energy characteristics at three U.S. wave energy converter (WEC) test and potential deployment sites. Its purpose is to enable the comparison of wave...

  4. MAGNETIC FIELD GENERATION AND PARTICLE ENERGIZATION AT RELATIVISTIC SHEAR BOUNDARIES IN COLLISIONLESS ELECTRON-POSITRON PLASMAS

    SciTech Connect (OSTI)

    Liang, Edison; Smith, Ian [Rice University, MS 108, 6100 Main Street, Houston, TX 77005 (United States); Boettcher, Markus, E-mail: liang@rice.edu, E-mail: iansmith@rice.edu, E-mail: boettchm@ohio.edu [Physics and Astronomy Department, Ohio University, Athens, OH 45701 (United States)

    2013-04-01

    Using particle-in-cell simulations, we study the kinetic physics of relativistic shear flow in collisionless electron-positron (e+e-) plasmas. We find efficient magnetic field generation and particle energization at the shear boundary, driven by streaming instabilities across the shear interface and sustained by the shear flow. Nonthermal, anisotropic high-energy particles are accelerated across field lines to produce a power-law tail turning over just below the shear Lorentz factor. These results have important implications for the dissipation and radiation of jets in blazars and gamma-ray bursts.

  5. The high-energy-density counterpropagating shear experiment and turbulent self-heating

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

    Doss, F. W.; Fincke, J. R.; Loomis, E. N.; Welser-Sherrill, L.; Flippo, K. A.

    2013-12-06

    The counterpropagating shear experiment has previously demonstrated the ability to create regions of shockdriven shear, balanced symmetrically in pressure and experiencing minimal net drift. This allows for the creation of a high-Mach-number high-energy-density shear environment. New data from the counterpropagating shear campaign is presented, and both hydrocode modeling and theoretical analysis in the context of a Reynolds-averaged-Navier-Stokes model suggest turbulent dissipation of energy from the supersonic flow bounding the layer is a significant driver in its expansion. A theoretical minimum shear flow Mach number threshold is suggested for substantial thermal-turbulence coupling.

  6. Absolute Measurement Of Laminar Shear Rate Using Photon Correlation Spectroscopy

    E-Print Network [OSTI]

    Elliot Jenner; Brian D'Urso

    2015-05-11

    An absolute measurement of the components of the shear rate tensor $\\mathcal{S}$ in a fluid can be found by measuring the photon correlation function of light scattered from particles in the fluid. Previous methods of measuring $\\mathcal{S}$ involve reading the velocity at various points and extrapolating the shear, which can be time consuming and is limited in its ability to examine small spatial scale or short time events. Previous work in Photon Correlation Spectroscopy has involved only approximate solutions, requiring free parameters to be scaled by a known case, or different cases, such as 2-D flows, but here we present a treatment that provides quantitative results directly and without calibration for full 3-D flow. We demonstrate this treatment experimentally with a cone and plate rheometer.

  7. SHEAR STRENGTH MEASURING EQUIPMENT EVALUATION AT THE COLD TEST FACILITY

    SciTech Connect (OSTI)

    MEACHAM JE

    2009-09-09

    Retrievals under current criteria require that approximately 2,000,000 gallons of double-shell tank (DST) waste storage space not be used to prevent creating new tanks that might be susceptible to buoyant displacement gas release events (BDGRE). New criteria are being evaluated, based on actual sludge properties, to potentially show that sludge wastes do not exhibit the same BDGRE risk. Implementation of the new criteria requires measurement of in situ waste shear strength. Cone penetrometers were judged the best equipment for measuring in situ shear strength and an A.P. van den berg Hyson 100 kN Light Weight Cone Penetrometer (CPT) was selected for evaluation. The CPT was procured and then evaluated at the Hanford Site Cold Test Facility. Evaluation demonstrated that the equipment with minor modification was suitable for use in Tank Farms.

  8. Discontinuous Shear Thickening in Brownian Suspensions By Dynamic Simulation

    E-Print Network [OSTI]

    Mari, Romain; Morris, Jeffrey F; Denn, Morton M

    2015-01-01

    Dynamic particle-scale numerical simulations are used to show that the shear thickening observed in dense colloidal, or Brownian, suspensions is of a similar nature to that observed in non-colloidal suspensions, i.e., a stress-induced transition from a flow of lubricated near-contacting particles to a flow of a frictionally contacting network of particles. Abrupt (or discontinuous) shear thickening is found to be a geometric rather than hydrodynamic phenomenon; it stems from the strong sensitivity of the jamming volume fraction to the nature of contact forces between suspended particles. The thickening obtained in a colloidal suspension of purely hard frictional spheres is qualitatively similar to experimental observations. However the agreement cannot be made quantitative with only hydrodynamics, frictional contacts and Brownian forces. Therefore the role of a short-range repulsive potential mimicking the stabilization of actual suspensions on the thickening is studied. The effects of Brownian and repulsive ...

  9. Hydrodynamic instabilities in shear flows of cohesive granular particles

    E-Print Network [OSTI]

    Kuniyasu Saitoh; Satoshi Takada; Hisao Hayakawa

    2015-05-15

    We extend the dynamic van der Waals model introduced by A. Onuki [Phys. Rev. Lett. 94, 054501 (2005)] to the description of cohesive granular flows under a plane shear to study their hydrodynamic instabilities. Numerically solving the dynamic van der Waals model, we observe various heterogeneous structures of the density in steady states, where the viscous heating is balanced with the energy dissipation caused by inelastic collisions. Based on the linear stability analysis, we find that the spatial structures are determined by the mean volume fraction, the applied shear rate, and the inelasticity, where the instability is triggered if the system is thermodynamically unstable, i.e. the pressure, $p$, and the volume fraction, $\\phi$, satisfy $\\partial p/\\partial\\phi<0$.

  10. Fluctuations and diffusion in sheared athermal suspensions of deformable particles

    E-Print Network [OSTI]

    Markus Gross; Timm Krüger; Fathollah Varnik

    2015-01-10

    We analyze fluctuations of particle displacements and stresses in a sheared athermal suspension of elastic capsules (red blood cells). Upon variation of the volume fraction from the dilute up to the highly concentrated regime, our numerical simulations reveal different characteristic power-law regimes of the fluctuation variances and relaxation times. In the jammed phase and at high shear rates, anomalous scaling exponents are found that deviate from pure dimensional predictions. The observed behavior is rationalized via kinetic arguments and a dissipation balance model that takes into account the local fluid flows between the particles. Our findings support the view that the rheology of dense suspensions is essentially governed by the non-affine displacements.

  11. Plasticity of a colloidal polycrystal under cyclic shear

    E-Print Network [OSTI]

    Elisa Tamborini; Luca Cipelletti; Laurence Ramos

    2014-08-27

    We use confocal microscopy and time-resolved light scattering to investigate plasticity in a col- loidal polycrystal, following the evolution of the network of grain boundaries as the sample is submitted to thousands of shear deformation cycles. The grain boundary motion is found to be ballistic, with a velocity distribution function exhibiting non-trivial power law tails. The shear- induced dynamics initially slow down, similarly to the aging of the spontaneous dynamics in glassy materials, but eventually reach a steady state. Surprisingly, the cross-over time between the ini- tial aging regime and the steady state decreases with increasing probed length scale, hinting at a hierarchical organization of the grain boundary dynamics.

  12. Accelerating cosmological expansion from shear and bulk viscosity

    E-Print Network [OSTI]

    Stefan Floerchinger; Nikolaos Tetradis; Urs Achim Wiedemann

    2015-03-10

    The dissipation of energy from local velocity perturbations in the cosmological fluid affects the time evolution of spatially averaged fluid dynamic fields and the cosmological solution of Einstein's field equations. We show how this backreaction effect depends on shear and bulk viscosity and other material properties of the dark sector, as well as the spectrum of perturbations. If sufficiently large, this effect could account for the acceleration of the cosmological expansion.

  13. Location of the solar dynamo and near-surface shear

    E-Print Network [OSTI]

    Axel Brandenburg

    2005-12-29

    The location of the solar dynamo is discussed in the context of new insights into the theory of nonlinear turbulent dynamos. It is argued that, from a dynamo-theoretic point of view, the bottom of the convection zone is not a likely location and that the solar dynamo may be distributed over the convection zone. The near surface shear layer produces not only east-west field alignment, but it also helps the dynamo disposing of its excess small scale magnetic helicity.

  14. Finite element analyses for seismic shear wall international standard problem

    SciTech Connect (OSTI)

    Park, Y.J.; Hofmayer, C.H.

    1998-04-01

    Two identical reinforced concrete (RC) shear walls, which consist of web, flanges and massive top and bottom slabs, were tested up to ultimate failure under earthquake motions at the Nuclear Power Engineering Corporation`s (NUPEC) Tadotsu Engineering Laboratory, Japan. NUPEC provided the dynamic test results to the OECD (Organization for Economic Cooperation and Development), Nuclear Energy Agency (NEA) for use as an International Standard Problem (ISP). The shear walls were intended to be part of a typical reactor building. One of the major objectives of the Seismic Shear Wall ISP (SSWISP) was to evaluate various seismic analysis methods for concrete structures used for design and seismic margin assessment. It also offered a unique opportunity to assess the state-of-the-art in nonlinear dynamic analysis of reinforced concrete shear wall structures under severe earthquake loadings. As a participant of the SSWISP workshops, Brookhaven National Laboratory (BNL) performed finite element analyses under the sponsorship of the U.S. Nuclear Regulatory Commission (USNRC). Three types of analysis were performed, i.e., monotonic static (push-over), cyclic static and dynamic analyses. Additional monotonic static analyses were performed by two consultants, F. Vecchio of the University of Toronto (UT) and F. Filippou of the University of California at Berkeley (UCB). The analysis results by BNL and the consultants were presented during the second workshop in Yokohama, Japan in 1996. A total of 55 analyses were presented during the workshop by 30 participants from 11 different countries. The major findings on the presented analysis methods, as well as engineering insights regarding the applicability and reliability of the FEM codes are described in detail in this report. 16 refs., 60 figs., 16 tabs.

  15. Shear Waves in an inhomogeneous strongly coupled dusty plasma

    E-Print Network [OSTI]

    Janaki, M S; Chakrabarti, N

    2013-01-01

    The properties of electrostatic transverse shear waves propagating in a strongly coupled dusty plasma with an equilibrium density gradient are examined using the generalized hydrodynamic equation. In the usual kinetic limit, the resulting equation has similarity to zero energy Schrodinger's equation. This has helped in obtaining some exact eigenmode solutions in both cartesian and cylindrical geometries for certain nontrivial density profiles. The corresponding velocity profiles and the discrete eigenfrequencies are obtained for several interesting situations and their physics discussed.

  16. COMPARISON OF SHEAR STRENGTH OF CERAMIC JOINTS DETERMINED BY VARIOUS TEST METHODS WITH SMALL SPECIMENS

    SciTech Connect (OSTI)

    Shih, Chunghao Phillip; Katoh, Yutai; Kiggans Jr, James O; Koyanagi, Takaaki; Khalifa, Hesham; Back, Christina A.; Hinoki, Tatsuya; Ferraris, Monica

    2015-01-01

    Four different shear test methods i.e. doubled notched shear test, asymmetrical four point bend test, Iosipescu test, and torsion test, were investigated for their ability to evaluate one standard SiC to SiC ceramic brittle joint while using small size specimens. Double notched shear test showed higher stress concentration at the notch base and a lower nominal shear strength. Both asymmetrical four point bend test and Iosipescu test utilized epoxy jointed metal extensors, which failed during test and caused misalignment and tensile type of failure. Torsion test can deliver true shear loading. However, base material failure was observed for the torsion joint samples in this study. None of the tests can successfully induce true shear failure of the joint because the joint is stronger and tougher than the SiC substrate. Torsion test appears to be promising because of the pure shear loading, less stress concentration, and easy alignment.

  17. Intensive neutrino source on the base of lithium converter

    E-Print Network [OSTI]

    Lyashuk, V I

    2015-01-01

    An intensive antineutrino source with a hard spectrum (with energy up to 13 MeV, average energy 6.5 MeV) can be realized on the base of beta-decay of short living isotope 8Li (0.84 s). The 8Li isotope (generated in activation of 7Li isotope) is a prime perspective antineutrino source owing to the hard antineutrino spectrum and square dependence of cross section on the energy. Up today nuclear reactors are the most intensive neutrino sources. Antineutrino reactor spectra have large uncertainties in the summary antineutrino spectrum at energy E>6 MeV. Use of 8Li isotope allows to decrease sharply the uncertainties or to exclude it completely. An intensive neutron fluxes are requested for rapid generation of 8Li isotope. The installations on the base of nuclear reactors can be an alternative for nuclear reactors as traditional neutron sources. It is possible creation of neutrino sources another in principle: on the base of tandem of accelerators, neutron generating targets and lithium converter. An intensive neu...

  18. How to convert gradually to oil-refinery hydrocracking

    SciTech Connect (OSTI)

    Basta, N.

    1986-01-06

    Over the past ten years, demand for refined petroleum products has been relatively constant, primarily because of worldwide conservation efforts. In fact, the demand for residual fuels has actually declined, while the market for gasoline has risen just slightly. Only middle distillates, which have seen a moderate increase since 1975, will continue to rise slowly over the next several years, says UOP Inc., a Des Plaines, Illinois, division of Allied-Signal Inc. This rise, coupled with the decline in resid demand, dictates the need for conversion capacity that will be capable of selectively producing distillate products. Traditionally, this need has been filled by hydrocracking gas oils to distillates. However, full conversion to hydrocracking requires high capital investment, which may not be possible in today's competitive refining industry. As a solution to this problem, UOP has developed a staged approach to distillate production, which allows the refiner both to phase in capital costs and to increase production over a number of years, says Mark Reno, manager of hydrocracking process development. The staged approach involves (1) constructing a mild-hydrocracking (MHC) unit that would produce less distillate, but at a lower cost; (2) upgrading to full conversion at a later date. The aldready-installed MHC equipment would be used with only minor modifications. UOP offers its own mild/full hydrocracking technology, called unibon; the firm says it can also convert a customer's existing hydrotreating equipment.

  19. Converting acoustic energy into useful other energy forms

    DOE Patents [OSTI]

    Putterman, Seth J. (Sherman Oaks, CA); Barber, Bradley Paul (Northridge, CA); Hiller, Robert Anthony (Los Angeles, CA); Lofstedt, Ritva Maire Johanna (Los Angeles, CA)

    1997-01-01

    Sonoluminescence is an off-equilibrium phenomenon in which the energy of a resonant sound wave in a liquid is highly concentrated so as to generate flashes of light. The conversion of sound to light represents an energy amplification of eleven orders of magnitude. The flashes which occur once per cycle of the audible or ultrasonic sound fields can be comprised of over one million photons and last for less 100 picoseconds. The emission displays a clocklike synchronicity; the jitter in time between consecutive flashes is less than fifty picoseconds. The emission is blue to the eye and has a broadband spectrum increasing from 700 nanometers to 200 nanometers. The peak power is about 100 milliWatts. The initial stage of the energy focusing is effected by the nonlinear oscillations of a gas bubble trapped in the liquid. For sufficiently high drive pressures an imploding shock wave is launched into the gas by the collapsing bubble. The reflection of the shock from its focal point results in high temperatures and pressures. The sonoluminescence light emission can be sustained by sensing a characteristic of the emission and feeding back changes into the driving mechanism. The liquid is in a sealed container and the seeding of the gas bubble is effected by locally heating the liquid after sealing the container. Different energy forms than light can be obtained from the converted acoustic energy. When the gas contains deuterium and tritium there is the feasibility of the other energy form being fusion, namely including the generation of neutrons.

  20. Cosmology from Cosmic Shear with DES Science Verification Data

    E-Print Network [OSTI]

    Abbott, T; Allam, S; Amara, A; Annis, J; Armstrong, R; Bacon, D; Banerji, M; Bauer, A H; Baxter, E; Becker, M R; Benoit-Lévy, A; Bernstein, R A; Bernstein, G M; Bertin, E; Blazek, J; Bonnett, C; Bridle, S L; Brooks, D; Bruderer, C; Buckley-Geer, E; Burke, D L; Busha, M T; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Castander, F J; Chang, C; Clampitt, J; Crocce, M; Cunha, C E; D'Andrea, C B; da Costa, L N; Das, R; DePoy, D L; Desai, S; Diehl, H T; Dietrich, J P; Dodelson, S; Doel, P; Drlica-Wagner, A; Efstathiou, G; Eifler, T F; Erickson, B; Estrada, J; Evrard, A E; Neto, A Fausti; Fernandez, E; Finley, D A; Flaugher, B; Fosalba, P; Friedrich, O; Frieman, J; Gangkofner, C; Garcia-Bellido, J; Gaztanaga, E; Gerdes, D W; Gruen, D; Gruendl, R A; Gutierrez, G; Hartley, W; Hirsch, M; Honscheid, K; Huff, E M; Jain, B; James, D J; Jarvis, M; Kacprzak, T; Kent, S; Kirk, D; Krause, E; Kravtsov, A; Kuehn, K; Kuropatkin, N; Kwan, J; Lahav, O; Leistedt, B; Li, T S; Lima, M; Lin, H; MacCrann, N; March, M; Marshall, J L; Martini, P; McMahon, R G; Melchior, P; Miller, C J; Miquel, R; Mohr, J J; Neilsen, E; Nichol, R C; Nicola, A; Nord, B; Ogando, R; Palmese, A; Peiris, H V; Plazas, A A; Refregier, A; Roe, N; Romer, A K; Roodman, A; Rowe, B; Rykoff, E S; Sabiu, C; Sadeh, I; Sako, M; Samuroff, S; Sánchez, C; Sanchez, E; Seo, H; Sevilla-Noarbe, I; Sheldon, E; Smith, R C; Soares-Santos, M; Sobreira, F; Suchyta, E; Swanson, M E C; Tarle, G; Thaler, J; Thomas, D; Troxel, M A; Vikram, V; Walker, A R; Wechsler, R H; Weller, J; Zhang, Y; Zuntz, J

    2015-01-01

    We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3\\% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find $\\sigma_8 (\\Omega_{\\rm m}/0.3)^{0.5} = 0.81 \\pm 0.06$ (68\\% confidence), after marginalising over 7 systematics parameters and 3 other cosmological parameters. We examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About $20$\\% of our error bar comes from marginalising over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data; our results are consistent with both datasets. Our uncertainties are $\\sim$30\\% larger than those from CFHTLenS when we carry out a comparable anal...

  1. Cosmic Shear Measurements with DES Science Verification Data

    E-Print Network [OSTI]

    Becker, M R; MacCrann, N; Krause, E; Eifler, T F; Friedrich, O; Nicola, A; Refregier, A; Amara, A; Bacon, D; Bernstein, G M; Bonnett, C; Bridle, S L; Busha, M T; Chang, C; Dodelson, S; Erickson, B; Evrard, A E; Frieman, J; Gaztanaga, E; Gruen, D; Hartley, W; Jain, B; Jarvis, M; Kacprzak, T; Kirk, D; Kravtsov, A; Leistedt, B; Rykoff, E S; Sabiu, C; Sanchez, C; Seo, H; Sheldon, E; Wechsler, R H; Zuntz, J; Abbott, T; Abdalla, F B; Allam, S; Armstrong, R; Banerji, M; Bauer, A H; Benoit-Levy, A; Bertin, E; Brooks, D; Buckley-Geer, E; Burke, D L; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Castander, F J; Crocce, M; Cunha, C E; D'Andrea, C B; da Costa, L N; DePoy, D L; Desai, S; Diehl, H T; Dietrich, J P; Doel, P; Neto, A Fausti; Fernandez, E; Finley, D A; Flaugher, B; Fosalba, P; Gerdes, D W; Gruendl, R A; Gutierrez, G; Honscheid, K; James, D J; Kuehn, K; Kuropatkin, N; Lahav, O; Li, T S; Lima, M; Maia, M A G; March, M; Martini, P; Melchior, P; Miller, C J; Miquel, R; Mohr, J J; Nichol, R C; Nord, B; Ogando, R; Plazas, A A; Reil, K; Romer, A K; Roodman, A; Sako, M; Sanchez, E; Scarpine, V; Schubnell, M; Sevilla-Noarbe, I; Smith, R C; Soares-Santos, M; Sobreira, F; Suchyta, E; Swanson, M E C; Tarle, G; Thaler, J; Thomas, D; Vikram, V; Walker, A R

    2015-01-01

    We present measurements of weak gravitational lensing cosmic shear two-point statistics using Dark Energy Survey Science Verification data. We demonstrate that our results are robust to the choice of shear measurement pipeline, either ngmix or im3shape, and robust to the choice of two-point statistic, including both real and Fourier-space statistics. Our results pass a suite of null tests including tests for B-mode contamination and direct tests for any dependence of the two-point functions on a set of 16 observing conditions and galaxy properties, such as seeing, airmass, galaxy color, galaxy magnitude, etc. We furthermore use a large suite of simulations to compute the covariance matrix of the cosmic shear measurements and assign statistical significance to our null tests. We find that our covariance matrix is consistent with the halo model prediction, indicating that it has the appropriate level of halo sample variance. We compare the same jackknife procedure applied to the data and the simulations in orde...

  2. Scaling properties in the production range of shear dominated flows

    E-Print Network [OSTI]

    C. M. Casciola; P. Gualtieri; B. Jacob; R. Piva

    2005-02-22

    Recent developments in turbulence are focused on the effect of large scale anisotropy on the small scale statistics of velocity increments. According to Kolmogorov, isotropy is recovered in the large Reynolds number limit as the scale is reduced and, in the so-called inertial range, universal features -namely the scaling exponents of structure functions - emerge clearly. However this picture is violated in a number of cases, typically in the high shear region of wall bounded flows. The common opinion ascribes this effect to the contamination of the inertial range by the larger anisotropic scales, i.e. the residual anisotropy is assumed as a weak perturbation of an otherwise isotropic dynamics. In this case, given the rotational invariance of the Navier-Stokes equations, the isotropic component of the structure functions keeps the same exponents of isotropic turbulence. This kind of reasoning fails when the anisotropic effects are strong as in the production range of shear dominated flows. This regime is analyzed here by means of both numerical and experimental data for a homogeneous shear flow. A well defined scaling behavior is found to exist, with exponents which differ substantially from those of classical isotropic turbulence. Contrary to what predicted by the perturbation approach, such a deep alteration concerns the isotropic sector itself. The general validity of these results is discussed in the context of turbulence near solid walls, where more appropriate closure models for the coarse grained Navier-Stokes equations would be advisable.

  3. Cosmic Shear Measurements with DES Science Verification Data

    SciTech Connect (OSTI)

    Becker, M. R.

    2015-07-20

    We present measurements of weak gravitational lensing cosmic shear two-point statistics using Dark Energy Survey Science Verification data. We demonstrate that our results are robust to the choice of shear measurement pipeline, either ngmix or im3shape, and robust to the choice of two-point statistic, including both real and Fourier-space statistics. Our results pass a suite of null tests including tests for B-mode contamination and direct tests for any dependence of the two-point functions on a set of 16 observing conditions and galaxy properties, such as seeing, airmass, galaxy color, galaxy magnitude, etc. We use a large suite of simulations to compute the covariance matrix of the cosmic shear measurements and assign statistical significance to our null tests. We find that our covariance matrix is consistent with the halo model prediction, indicating that it has the appropriate level of halo sample variance. We also compare the same jackknife procedure applied to the data and the simulations in order to search for additional sources of noise not captured by the simulations. We find no statistically significant extra sources of noise in the data. The overall detection significance with tomography for our highest source density catalog is 9.7?. Cosmological constraints from the measurements in this work are presented in a companion paper (DES et al. 2015).

  4. Aalborg Universitet Review on Multi-Level Voltage Source Converter Based HVDC Technologies for Grid

    E-Print Network [OSTI]

    Bak, Claus Leth

    Connection of Large Offshore Wind Farms Glasdam, Jakob ; Hjerrild, Jesper; Kocewiak, Lukasz Hubert; Bak-Level Voltage Source Converter Based HVDC Technologies for Grid Connection of Large Offshore Wind Farms. I IEEE of large offshore wind farms (OWFs) employing current state-of- the-art voltage source converter based high

  5. A hybrid switched-capacitor/inductor converter for small conversion ratios

    E-Print Network [OSTI]

    Nakibuuka, Norah Elena

    2013-01-01

    A hybrid three-switch DC-DC step-up power converter for on chip applications is proposed. It is shown that the hybrid-three switch step-up converter can offer advantages such as reduced size of magnetic components, reduced ...

  6. Design of high speed low voltage data converters for UWB communication systems 

    E-Print Network [OSTI]

    Lee, Choong Hoon

    2006-08-16

    For A/D converters in ultra-wideband (UWB) communication systems, the flash A/D type is commonly used because of its fast speed and simple architecture. However, the number of comparators in a flash A/D converter exponentially ...

  7. Aalborg Universitet An assessment of converter modelling needs for offshore wind power plants

    E-Print Network [OSTI]

    Bak, Claus Leth

    Aalborg Universitet An assessment of converter modelling needs for offshore wind power plants). An assessment of converter modelling needs for offshore wind power plants connected via VSC-HVDC networks Power into Power Systems as well as on Transmission Networks for Offshore Wind Plants. Energynautics

  8. Aalborg Universitet Harmonic Analysis of Offshore Wind Farms with Full Converter Wind Turbines

    E-Print Network [OSTI]

    Bak, Claus Leth

    Aalborg Universitet Harmonic Analysis of Offshore Wind Farms with Full Converter Wind Turbines Analysis of Offshore Wind Farms with Full Converter Wind Turbines. In Proceeding of the 8th International.aau.dk on: juli 06, 2015 #12; Abstract--This paper presents the harmonic analysis of offshore wind farm (OWF

  9. Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News

    E-Print Network [OSTI]

    Lovley, Derek

    Solar Power To Help Convert Carbon Dioxide Into Fuel : Renewable Energy News TUESDAY 25 MAY, 2010 | | Solar Power To Help Convert Carbon Dioxide Into Fuel by Energy Matters Microbiologist Derek Lovley of energy, the solar panels, can also harvest energy 100 times more effectively than plants. Other

  10. Regulation and Compensation of Source Harmonics for the Boost ConverterBased Power Factor

    E-Print Network [OSTI]

    Perreault, Dave

    Regulation and Compensation of Source Harmonics for the Boost Converter­Based Power Factor of a diode bridge and associated boost converter. This circuit is the most widely employed of the fam- ily for the boost­ based power factor precompensator which guarantees fast regulation of the output voltage towards

  11. Single Comparator Based A/D Converter for Output Voltage Sensing in

    E-Print Network [OSTI]

    Single Comparator Based A/D Converter for Output Voltage Sensing in Power Factor Correction frequency (2fline) without the use of a traditional analog to digital converter (A/D). The proposed method/D or a traditional A/D in a digitally controlled 300W boost PFC. I. INTRODUCTION Many implementations of digital

  12. Digital Control Strategy for Multi-Phase Interleaved Boundary Mode and DCM Boost PFC Converters

    E-Print Network [OSTI]

    Noé, Reinhold

    Digital Control Strategy for Multi-Phase Interleaved Boundary Mode and DCM Boost PFC Converters T switching frequency, DCM boost PFC converter can be operated with constant as well as with variable.schafmeister@delta-es.com Abstract-- A digital control strategy which provides optimal interleaving of multi-phase boost power factor

  13. Time domain design of digital compensators for PWM DC-DC converters

    E-Print Network [OSTI]

    transformation and discretization. Digital PID controllers for a Buck and Boost type converters were implemented (via the various transformation algorithms), a digital compensator operates, in reality, in the sampledTime domain design of digital compensators for PWM DC-DC converters Mor Mordechai Peretz and Sam

  14. Sensorless Current Sharing in Digitally Controlled Two-Phase Buck DC-DC Converters

    E-Print Network [OSTI]

    is discussed. Experimental results are shown for a two-phase synchronous buck converter with 6V input voltage synchronous buck converter shown in Fig.1 has been built to test the proposed sensorless current sharing the digital command d. A sensorless current sharing block generates two command duty cycles d1 and d2 in order

  15. A New Approach to Solving the Harmonic Elimination Equations for a Multilevel Converter

    E-Print Network [OSTI]

    Tolbert, Leon M.

    is required. A multilevel inverter is ideal for connecting such distributed dc energy sources (solar cellsA New Approach to Solving the Harmonic Elimination Equations for a Multilevel Converter John N that the transcendental equations characterizing the har- monic content can be converted to polynomial equations which

  16. Bi-directional Current-fed Medium Frequency Transformer Isolated AC-DC Converter 

    E-Print Network [OSTI]

    Essakiappan, Somasundaram

    2011-08-08

    demand for power converters with bi-directional capabilities. The objective of this thesis is to develop a high power quality, bi-directional AC-DC power converter that is a solution to the aforementioned problems. This thesis studies an existing topology...

  17. Fault-tolerant Partial-resonant High-frequency AC-link Converters and Their Applications 

    E-Print Network [OSTI]

    Keyhani, Hamidreza

    2014-01-08

    in the converter shutdown, and thus system availability is improved. The high-frequency ac link of the introduced converters is composed of an ac inductor and small ac capacitor. The link inductor is responsible for transferring power, while the link capacitor...

  18. ROM-less RNS-to-binary converter moduli Pedro Miguens Matutino

    E-Print Network [OSTI]

    Sousa, Leonel

    ROM-less RNS-to-binary converter moduli {22 - 1, 22 + 1, 2 - 3, 2 + 3} Pedro Miguens Matutino ISEL--In this paper, a novel ROM-less RNS-to-binary converter is proposed, using a new balanced moduli set {22 - 1, 22 metric can be achieved for the full RNS architecture using the proposed moduli set. Keywords

  19. ASIC and FPGA Implementations of Modern 4-Moduli RNS Reverse Converters

    E-Print Network [OSTI]

    Sousa, Leonel

    ASIC and FPGA Implementations of Modern 4-Moduli RNS Reverse Converters Using Distinct complex and essential part of residue number system (RNS), and has a significant role in the general performance of RNS. Recently, it is showed that the reverse converter performance could be significantly

  20. Memoryless RNS-to-Binary Converters for the {2n+1 -1} Moduli Set

    E-Print Network [OSTI]

    Cotofana, Sorin

    Memoryless RNS-to-Binary Converters for the {2n+1 - 1, 2n , 2n - 1} Moduli Set Kazeem Alagbe, Memoryless Converter. I.. Introduction The Residue Number System (RNS) is a non-weighted number system that utilizes remainders to represent num- bers. RNS has received considerable attention in arithmetic

  1. Accelerated lifetime testing of energy storage capacitors used in particle accelerators power converters

    E-Print Network [OSTI]

    Boattini, Fulvio

    2015-01-01

    Energy storage capacitors are used in large quantities in high power converters for particle accelerators. In this application capacitors see neither a DC nor an AC voltage but a combination of the two. The paper presents a new power converter explicitly designed to perform accelerated testing on these capacitors and the results of the tests.

  2. Application of wave generator theory to the development of a Wave Energy Converter

    E-Print Network [OSTI]

    Wood, Stephen L.

    Application of wave generator theory to the development of a Wave Energy Converter by Maila Sepri approve the attached thesis Application of wave generator theory to the development of a Wave Energy Application of wave generator theory to the development of a Wave Energy Converter by Maila Sepri Principal

  3. Development of SNL-SWAN, a Validated Wave Energy Converter Array Modeling Tool

    E-Print Network [OSTI]

    Siefert, Chris

    Development of SNL-SWAN, a Validated Wave Energy Converter Array Modeling Tool Kelley Ruehl#1 energy will lead to the necessary deployment of Wave Energy Converters (WECs) in arrays, or wave farms state dependent wave energy conversion of WECs. Keywords-- wave energy, wave farm, WEC array, SWAN

  4. Influence of control strategy on the global efficiency of a Direct Wave Energy Converter with

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Influence of control strategy on the global efficiency of a Direct Wave Energy Converter, France Abstract--The choice of control strategy for Direct Wave Energy Converters (DWEC) is often a simple loss model in order to design a better control strategy. Keywords--Wave energy conversion; Point

  5. Control influence on the electromagnetic generator pre-design for a wave energy converter

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    461 1 Control influence on the electromagnetic generator pre-design for a wave energy converter M of an electromagnetic generator for wave energy recovery. We will start by describing the wave energy converter (WEC of the study problem. Keywords: optimization, control, design methodology, direct drive generator, wave energy

  6. Study of Power Converter Topologies with Energy Recovery and grid power flow control Part B: boost converter with energy storage

    E-Print Network [OSTI]

    Rogelio, Garcia Retegui; Gustavo, Uicich; Mario, Benedetti; Gilles, Le Godec; Konstantinos, Papastergiou

    2015-01-01

    In the framework of a Transfer line (TT2) Consolidation Programme, a number of studies on Energy cycling have been commissioned. Part of this work involves the study of dierent power electronic system topologies for magnet energy recovery. In this report, the use of a boost front-end converter supplying DC link of a 4-quadrant magnet supply is analysed. The key objective of the study is to find control strategies that result in the control of the peak power required from the power network as well as to recover the magnet energy into capacitor banks with controlled voltage fluctuation. The study comprises the modelling of the system by means of the method of state averaging and the development of regulation strategies to energy management. The proposed control strategies can be divided in two groups: in the first group, the magnet current is used to define the reference for the control system, while in the second group this current is unknown and some strategies are devised to limit the power drawn from the el...

  7. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    DOE Patents [OSTI]

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  8. Utility-Scale Power Router: Dynamic Control of Grid Assets Using Direct AC Converter Cells

    SciTech Connect (OSTI)

    2010-09-01

    ADEPT Project: Georgia Tech is developing a cost-effective, utility-scale power router that uses an enhanced transformer to more efficiently direct power on the grid. Existing power routing technologies are too expensive for widespread use, but the ability to route grid power to match real-time demand and power outages would significantly reduce energy costs for utilities, municipalities, and consumers. Georgia Tech is adding a power converter to an existing grid transformer to better control power flows at about 1/10th the cost of existing power routing solutions. Transformers convert the high-voltage electricity that is transmitted through the grid into the low-voltage electricity that is used by homes and businesses. The added converter uses fewer steps to convert some types of power and eliminates unnecessary power storage, among other improvements. The enhanced transformer is more efficient, and it would still work even if the converter fails, ensuring grid reliability.

  9. Analysis of PS-converted wave seismic data in the presence of azimuthal anisotropy 

    E-Print Network [OSTI]

    Liu, Weining

    2014-11-27

    Shear-wave splitting and azimuthal variations of seismic attributes are two major anisotropic effects induced by vertically-aligned fractures. They both have influences on seismic data processing and interpretation, and ...

  10. A generic model for transport in turbulent shear flows

    SciTech Connect (OSTI)

    Newton, Andrew P. L.; Kim, Eun-Jin [Department of Applied Mathematics, University of Sheffield, Sheffield, S3 7RH (United Kingdom)

    2011-05-15

    Turbulence regulation by large-scale shear flows is crucial for a predictive modeling of transport in plasma. In this paper the suppression of turbulent transport by large-scale flows is studied numerically by measuring the turbulent diffusion D{sub t} and scalar amplitude of decaying passive scalar fields n{sup '} advected by various turbulent flows. Both uniform flows and shear flows are shown to suppress turbulence causing the quenching in transport and turbulence amplitude. The uniform flows U{sub 0}={Lambda}y with the advection rate {Lambda} in the case of a finite correlated forcing with {tau}{sub F}=1 gives rise to the advection/sweeping effect which suppresses D{sub t}, and as {proportional_to}{Lambda}{sup -2} for {Lambda}>>{tau}{sub F}{sup -1}. In contrast, no influence of the uniform flow is found in the case of a short correlated forcing {tau}{sub F}{yields}0 due to Galilean invariance. For the shear flow U{sub 0}={Omega}sinxy ({Omega}= constant shearing rate) with the appropriate choice of the forcing ({tau}{sub F}{yields}0) the nature of transport suppression is shown to crucially depend on the properties of the turbulence. Specifically, for prescribed turbulence with a short correlation time {tau}{sub c}={tau}{sub F}<<{Omega}{sup -1}, the turbulence statistics scale as D{sub t{proportional_to}{Omega}}{sup -0.02}, {proportional_to}{Omega}{sup -0.62} and cross-phase cos{theta}{proportional_to}{Omega}{sup 0.29}. For consistently evolved turbulence with a finite correlation time {tau}{sub c{>=}{Omega}}{sup -1}, turbulence statistics are suppressed more strongly as D{sub t{proportional_to}{Omega}}{sup -1.75}, {proportional_to}{Omega}{sup -2.41}, {proportional_to}{Omega}{sup -0.65} and <{omega}{sup '2}>{proportional_to}{Omega}{sup -0.50}. A novel renormalization scheme is then introduced to rescale our results into the regime within which the kinetic energy and enstrophy are unchanged by shear flow. This allows our numerical results to closely match previous analytical predictions [E. Kim, Mod. Phys. Lett. B 18, 1 (2004)] and to understand different experimental scalings observed in laboratory plasmas. Furthermore, D{sub t} is found to be related to by {proportional_to}D{sub t}/D{sub {Omega}}, where D{sub {Omega}}{proportional_to}{Omega}{sup (2/3)} is the shear accelerated diffusion of n{sup '} with an interesting scaling cos{theta}{proportional_to}{radical}(D{sub t}D{sub {Omega}}).

  11. Shear properties on aluminum metal foams prepared by the melt route

    SciTech Connect (OSTI)

    Saenz, E. [UTRC GmbH, Aachen (Germany). Technologiezentrum; Baranda, P.S. [UTRC, S.L., Minano (Spain); Bonhomme, J. [ITMA, Coruno-Llanera (Spain). Parque Tecnologico de Asturias

    1998-12-31

    The shear modulus and shear strength of AlSi7Mg Aluminum foam with 15% (vol) of 13 {micro}m SiC particles were determined through shear testing. A foam slab with a density of 0.31 g/cm3 was supplied by Hydro Aluminium. Four samples were tested according to ASTM C 273-61. The specimens were bonded to steel load plates. The relative displacement of the plates was measured using two extensometers. In order to evaluate the effect of the cell size distribution on shear properties, cell size and material distribution analyses were carried out for the metal foam slab in areas close to those from which the shear specimens were extracted. A fast failure was observed after the maximum shear load. The failure in the samples were located in the central section of the slab mainly because the lower density was located there.

  12. Error-field penetration in reversed magnetic shear configurations

    SciTech Connect (OSTI)

    Wang, H. H.; Wang, Z. X.; Wang, X. Q. [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China)] [MOE Key Laboratory of Materials Modification by Beams of the Ministry of Education, School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Wang, X. G. [School of Physics, Peking University, Beijing 100871 (China)] [School of Physics, Peking University, Beijing 100871 (China)

    2013-06-15

    Error-field penetration in reversed magnetic shear (RMS) configurations is numerically investigated by using a two-dimensional resistive magnetohydrodynamic model in slab geometry. To explore different dynamic processes in locked modes, three equilibrium states are adopted. Stable, marginal, and unstable current profiles for double tearing modes are designed by varying the current intensity between two resonant surfaces separated by a certain distance. Further, the dynamic characteristics of locked modes in the three RMS states are identified, and the relevant physics mechanisms are elucidated. The scaling behavior of critical perturbation value with initial plasma velocity is numerically obtained, which obeys previously established relevant analytical theory in the viscoresistive regime.

  13. Thermal evolution of a radiating anisotropic star with shear

    E-Print Network [OSTI]

    N F Naidu; M Govender; K S Govinder

    2005-12-02

    We study the effects of pressure anisotropy and heat dissipation in a spherically symmetric radiating star undergoing gravitational collapse. An exact solution of the Einstein field equations is presented in which the model has a Friedmann-like limit when the heat flux vanishes. The behaviour of the temperature profile of the evolving star is investigated within the framework of causal thermodynamics. In particular, we show that there are significant differences between the relaxation time for the heat flux and the relaxation time for the shear stress.

  14. Apparent Fracture in Polymeric Fluids under Step Shear

    E-Print Network [OSTI]

    Okpeafoh S. Agimelen; Peter D. Olmsted

    2013-05-16

    Recent step strain experiments in well-entangled polymeric liquids demonstrated a bulk fracture-like phenomenon. We have studied this instability using a modern version of the Doi-Edwards theory for entangled polymers, and we find close quantitative agreement with the experiments. The phenomenon occurs because the viscoelastic liquid is sheared into a rubbery state that possesses an elastic constitutive instability (Marrucci and Grizzuti, 1983). The fracture is a transient manifestation of this instability, which relies on the amplification of spatially inhomogeneous fluctuations. This mechanism differs from fracture in glassy materials and dense suspensions.

  15. Yield stress and shear-banding in granular suspensions

    E-Print Network [OSTI]

    Abdoulaye Fall; Francois Bertrand; Guillaume Ovarlez; Daniel Bonn

    2009-07-13

    We study the emergence of a yield stress in dense suspensions of non-Brownian particles, by combining local velocity and concentration measurements using Magnetic Resonance Imaging with macroscopic rheometric experiments. We show that the competition between gravity and viscous stresses is at the origin of the development of a yield stress in these systems at relatively low volume fractions. Moreover, it is accompanied by a shear banding phenomenon that is the signature of this competition. However, if the system is carefully density matched, no yield stress is encountered until a volume fraction of 62.7 0.3%.

  16. Gravitational collapse, shear-free anisotropic radiating star

    E-Print Network [OSTI]

    B. C. Tewari; Kali Charan

    2015-03-07

    We present a class of exact solutions of Einstein field equations for a shear-free spherically symmetric anisotropic fluid undergoing radial heat flow. The interior metric fulfilled all the relevant physical and thermodynamic conditions and matched with Vaidya exterior metric over the boundary. Initially the interior solutions represent a static configuration of dissipative fluid which then gradually starts evolving into radiating collapse. The apparent luminosity observed by the distant observer at rest at infinity and the effective surface temperature are zero in remote past at the instance when collapse begins and at the stage when collapsing configuration reach the horizon of the black hole.

  17. SEISMIC EVALUATION OF ATYPICAL SPECIAL PLATE SHEAR WALLS

    SciTech Connect (OSTI)

    Mark J. Russell; Robert E. Spears; Ryan G. Kobbe

    2007-07-01

    The structure of a building undergoing a seismic reevaluation at the Idaho National Laboratory includes a number of steel plate walls and a roof liner which will act as shear diaphragms during an earthquake. Since the facility was designed and built long before such criteria were formulated, it is not surprising that these walls are not configured to meet all of the recently formulated requirements for such structures. To take advantage of this unusual structural feature, nonlinear analysis was used to ensure accurate modeling of the plate walls in a linear elastic seismic analysis of the full superstructure. The modeling was also used to establish the capacity of the plate.

  18. A Generalized Class of Stationary Frame-Current Controllers for Grid-Connected AC–DC Converters

    E-Print Network [OSTI]

    Hwang, J. George

    Within power systems, high-power pulsewidth-modulated ac-dc converters are used in flexible ac transmission systems controllers and for interfacing renewable energy sources to the grid. These converters traditionally ...

  19. Anisotropic Mobility Model for Polymers under Shear and its Linear Response Functions

    E-Print Network [OSTI]

    Takashi Uneyama; Kazushi Horio; Hiroshi Watanabe

    2011-04-19

    We propose a simple dynamic model of polymers under shear with an anisotropic mobility tensor. We calculate the shear viscosity, the rheo-dielectric response function, and the parallel relaxation modulus under shear flow deduced from our model. We utilize recently developed linear response theories for nonequilibrium systems to calculate linear response functions. Our results are qualitatively consistent with experimental results. We show that our anisotropic mobility model can reproduce essential dynamical nature of polymers under shear qualitatively. We compare our model with other models or theories such as the convective constraint release model or nonequilibrium linear response theories.

  20. Estimating Undrained Strength of Clays from Direct Shear Testing at Fast Displacement Rates

    E-Print Network [OSTI]

    Bro, Andrew D; Stewart, Jonathan P; Pradel, Daniel E

    2013-01-01

    and Mesri, G. (1996) Soil Mechanics in Engineering Practice,soil shearing near the edge of the tank. Bro (2007) discussed in greater detail the mechanics

  1. Shear Zones in granular materials: Optimization in a self-organized random potential

    E-Print Network [OSTI]

    J Torok; T. Unger; J. Kertesz; D. E. Wolf

    2006-07-06

    We introduce a model to describe the wide shear zones observed in modified Couette cell experiments with granular material. The model is a generalization of the recently proposed approach based on a variational principle. The instantaneous shear band is identified with the surface that minimizes the dissipation in a random potential that is biased by the local velocity difference and pressure. The apparent shear zone is the ensemble average of the instantaneous shear bands. The numerical simulation of this model matches excellently with experiments and has measurable predictions.

  2. The Viability of Sustainable, Self-Propping Shear Zones in Ehanced...

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

    The Viability of Sustainable, Self-Propping Shear Zones in Ehanced Geothermal Systems: Measurement of Reaction Rates at Elevated Temperatures The Viability of Sustainable,...

  3. XIAP is essential for shear stress-enhanced Tyr-576 phosphorylation of FAK

    SciTech Connect (OSTI)

    Ahn, Sunyoung [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do, 448-701 (Korea, Republic of)] [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do, 448-701 (Korea, Republic of); Park, Heonyong, E-mail: heonyong@dankook.ac.kr [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do, 448-701 (Korea, Republic of)] [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do, 448-701 (Korea, Republic of)

    2010-08-20

    Research highlights: {yields} Laminar shear stress phosphorylates Tyr-576 in FAK. {yields} XIAP is essential for shear stress-induced phosphorylation of Tyr-576. {yields} XIAP knockdown induces shear stress-triggered translocation of FAK into nucleus. {yields} XIAP regulates ERK activation by maintaining the Src-accessible location of FAK. -- Abstract: In endothelial cells, X-chromosome linked inhibitor of apoptosis protein (XIAP) regulates cell survival, migration and adhesion. We have recently found that XIAP recruits focal adhesion kinase (FAK) into integrin-associated focal adhesions, controlling cell migration. However, little is understood about the molecular mechanisms by which FAK modulation is controlled by XIAP. In this study, we show that XIAP modulates FAK activity through the control of FAK phosphorylation. In bovine aortic endothelial cells (BAEC), phosphorylation of Tyr-576 in FAK is elevated by laminar shear stress. This elevated phosphorylation appears to be responsible for shear stress-stimulated ERK activation. We found that XIAP knockdown reduces shear stress-enhanced phosphorylation of Tyr-576 and induces shear stress-triggered translocation of FAK into nucleus. Nuclear translocation of FAK reduces contact between FAK and Src, a kinase which phosphorylates Tyr-576. This spatial segregation of FAK from Src decreases Tyr-576 phosphorylation and thus shear-stimulated ERK activation. Taken together, our results demonstrate that XIAP plays a key role in shear stress-stimulated ERK activation by maintaining the Src-accessible location of FAK.

  4. Active Vorticity Control in a Shear Flow Using a Flapping Foil

    E-Print Network [OSTI]

    Gopalkrishnan, R.

    1994-01-01

    It is shown experimentally that free shear flows can be substantially altered through direct control of the large coherent vortices present in the flow.

  5. Determination of the shear and extensional rheology of bubbly liquids with a shear-thinning continuous phase

    E-Print Network [OSTI]

    Torres, M.D.; Hallmark, B.; Wilson, D.I.

    2015-01-17

    , -??(*?dimensionless shear stress, -????parameter from Choi and Schowalter model, -????angular velocity, rad/s??Introduction Bubbly liquids are dispersions of a gas, ofair, in a liquid with low to medium volume fraction of the bubble phase so that the bubbles remain... that there was negligible contribution from wall slip. Samples were loaded carefully to ensure minimal structural damage, and held at rest for 5 min before testing to allow stress relaxation and temperature equilibration. A thin film of a Newtonian silicone oil (viscosity 1...

  6. A High Efficiency DC-DC Converter Topology Suitable for Distributed Large Commercial and Utility Scale PV Systems

    SciTech Connect (OSTI)

    Mohammed S. Agamy; Maja Harfman-Todorovic; Ahmed Elasser; Robert L. Steigerwald; Juan A. Sabate; Song Chi; Adam J. McCann; Li Zhang; Frank Mueller

    2012-09-01

    In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements

  7. Bifurcations in annular electroconvection with an imposed shear

    E-Print Network [OSTI]

    Zahir A. Daya; Vatche B. Deyirmenjian; Stephen W. Morris

    2001-04-13

    We report an experimental study of the primary bifurcation in electrically-driven convection in a freely suspended film. A weakly conducting, submicron thick smectic liquid crystal film was supported by concentric circular electrodes. It electroconvected when a sufficiently large voltage $V$ was applied between its inner and outer edges. The film could sustain rapid flows and yet remain strictly two-dimensional. By rotation of the inner electrode, a circular Couette shear could be independently imposed. The control parameters were a dimensionless number ${\\cal R}$, analogous to the Rayleigh number, which is $\\propto V^2$ and the Reynolds number ${\\cal R}e$ of the azimuthal shear flow. The geometrical and material properties of the film were characterized by the radius ratio $\\alpha$, and a Prandtl-like number ${\\cal P}$. Using measurements of current-voltage characteristics of a large number of films, we examined the onset of electroconvection over a broad range of $\\alpha$, ${\\cal P}$ and ${\\cal R}e$. We compared this data quantitatively to the results of linear stability theory. This could be done with essentially no adjustable parameters. The current-voltage data above onset were then used to infer the amplitude of electroconvection in the weakly nonlinear regime by fitting them to a steady-state amplitude equation of the Landau form. We show how the primary bifurcation can be tuned between supercritical and subcritical by changing $\\alpha$ and ${\\cal R}e$.

  8. High Shear Regions in Weak Lensing Surveys Determine Cosmology

    E-Print Network [OSTI]

    Sheng Wang; Zoltan Haiman; Morgan May; John Kehayias

    2008-09-24

    We propose to use a simple observable, the fractional area of "hot spots" in weak lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-shear regions are directly related to the physical non-linear structures of the universe, they derive cosmological information mainly from the non-linear regime of density fluctuations. We show that in combination with future cosmic microwave background (CMB) anisotropy measurements, this method can place constraints on cosmological parameters that are comparable to those from the redshift distribution of galaxy cluster abundances. In particular, adding the information from this simple shear statistic derived from an LSST-like survey to CMB anisotropy information from a Planck-like experiment improves the constraints on the dark energy parameters (energy density and equation of state) and the normalization of the matter power spectrum by over a factor of ten. The main advantage of the statistic proposed in this paper is that projection effects, normally the main source of uncertainty when determining the presence and the mass of a galaxy cluster, here serve as a source of information.

  9. Oblique waves on a vertically sheared current are rotational

    E-Print Network [OSTI]

    Ellingsen, Simen Å

    2015-01-01

    In the study of surface waves in the presence of a shear current, a useful and much studied model is that in which the shear flow has constant vorticity. Recently it was shown by Constantin [Eur. J. Mech. B/Fluids 30 (2011) 12-16] that a flow of constant vorticity can only permit waves travelling exactly upstream or downstream, but not at oblique angles to the current, and several proofs to the same effect have appeared thereafter. Physical waves cannot possibly adhere to such a restriction, however. We resolve the paradox by showing that an oblique plane wave propagating atop a current of constant vorticity according to the linearized Euler equation carries with it an undulating perturbation of the vorticity field, hence is not prohibited by the Constantin theorem since vorticity is not constant. The perturbation of the vorticity field is readily interpreted in a Lagrangian perspective as the wave motion gently shifting and twisting the vortex lines as the wave passes. In the special case of upstream or down...

  10. Onset and cessation of motion in hydrodynamically sheared granular beds

    E-Print Network [OSTI]

    Abram H. Clark; Mark D. Shattuck; Nicholas T. Ouellette; Corey S. O'Hern

    2015-10-06

    We performed molecular dynamics simulations of granular beds driven by a model hydrodynamic shear flow to elucidate general grain-scale mechanisms that determine the onset and cessation of sediment transport. By varying the Shields number (the nondimensional shear stress at the top of the bed) and particle Reynolds number (the ratio of particle inertia to viscous damping), we explore how variations of the fluid flow rate, particle inertia, and fluid viscosity affect the onset and cessation of bed motion. For low to moderate particle Reynolds numbers, a critical boundary separates mobile and static states. Transition times between these states diverge as this boundary is approached both from above and below. At high particle Reynolds number, inertial effects become dominant, and particle motion can be sustained well below flow rates at which mobilization of a static bed occurs. We also find that the onset of bed motion (for both low and high particle Reynolds numbers) is described by Weibullian weakest-link statistics, and thus is crucially dependent on the packing structure of the granular bed, even deep beneath the surface.

  11. Discontinuous Shear Thickening in Brownian Suspensions By Dynamic Simulation

    E-Print Network [OSTI]

    Romain Mari; Ryohei Seto; Jeffrey F. Morris; Morton M. Denn

    2015-08-05

    Dynamic particle-scale numerical simulations are used to show that the shear thickening observed in dense colloidal, or Brownian, suspensions is of a similar nature to that observed in non-colloidal suspensions, i.e., a stress-induced transition from a flow of lubricated near-contacting particles to a flow of a frictionally contacting network of particles. Abrupt (or discontinuous) shear thickening is found to be a geometric rather than hydrodynamic phenomenon; it stems from the strong sensitivity of the jamming volume fraction to the nature of contact forces between suspended particles. The thickening obtained in a colloidal suspension of purely hard frictional spheres is qualitatively similar to experimental observations. However the agreement cannot be made quantitative with only hydrodynamics, frictional contacts and Brownian forces. Therefore the role of a short-range repulsive potential mimicking the stabilization of actual suspensions on the thickening is studied. The effects of Brownian and repulsive forces on the onset stress can be combined in an additive manner. The simulations including Brownian and stabilizing forces show excellent agreement with experimental data for the viscosity $\\eta$ and the second normal stress difference $N_2$.

  12. Trace-element zoning in garnets from sheared mantle xenoliths

    SciTech Connect (OSTI)

    Griffin, W.L.; Cousens, D.R.; Ryan, C.G.; Sie, S.H.; Suter, G.F. ); Smith, D. ); Boyd, F.R. )

    1989-02-01

    Proton-microprobe analyses of garnets from sheared high-temperature ultramafic xenoliths reveal marked zonation of trace elements, paralleling trends in major and minor elements. Garnet rims (600-1,000 {mu}m wide) are enriched in Fe, Ti, Zr, Y and Ga, and either enriched or depleted in Cr, relative to cores. Zoning profiles for Ti and Zr are S-shaped and extend further into the grains than the Cr and Ga gradients. The profiles are consistent with the formation of Ti, Zr, Y-enriched garnet overgrowths, followed by diffusive equilibration between rim and core over years to hundreds of years. This enrichment in Fe, Ca, Al and incompatible elements is ascribed to melt infiltration and consequent melt-crystal exchange and garnet growth, shortly before eruption. Zr/Y is 1 to 2 in garnet cores but 4 to 5 in rims, and so the infiltrating melt may have been relatively alkalic. Major and trace element concentrations in such high-temperature sheared xenoliths are not likely to resemble those of primitive mantle or of residual mantle depleted by melt extraction.

  13. Interaction of Fast-Scale and Slow-Scale Bifurcations in Current-Mode Controlled DC/DC Converters

    E-Print Network [OSTI]

    Tse, Chi K. "Michael"

    of fast-scale and slow-scale bifurcations in the boost converter under current- mode control operating, and it manifests as period-doubling in the time scale, as reported in Iu et al. [7] for parallel boost converters, Wong et al. [8] for noise-coupled boost converters, and Wu et al. [9] for power

  14. Abstract Many control schemes for dc-dc converters begin with the assertion that inductor currents are "fast" states and

    E-Print Network [OSTI]

    Kimball, Jonathan W.

    work, singular perturbation theory is applied to boost converters to provide rigorous justification derives from an analysis of an approximate model. Similar results hold for buck and buck-boost converters. An experimental boost converter and a simulated PFC boost support the derived requirement. Keywords

  15. Experimental Evaluation of a Cascade Sliding Mode-PI Controller for a Coupled-Inductor Boost Converter

    E-Print Network [OSTI]

    Batlle, Carles

    the experimental results ob- tained for a cascade sliding mode PI control in a coupled-inductor Boost converter) operations. A piece- wise complementarity model of the coupled-inductor boost converter was proposed in [6 control for a coupled-inductor boost converter was proposed. The control strategy was developed using

  16. Fig.1: Digital Controller with modified buck-boost converter LOAD-INTERACTIVE STEERED-INDUCTOR DC-DC

    E-Print Network [OSTI]

    Prodiæ, Aleksandar

    Fig.1: Digital Controller with modified buck-boost converter LOAD-INTERACTIVE STEERED-INDUCTOR DC-inverting buck- boost. Transient response results show that, compared to standard converters with near-inverting buck-boost converter, i.e. steered-inductor buck-boost, a digital controller, and a communication block

  17. Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating Current

    E-Print Network [OSTI]

    Phase-Shifted Full Bridge DC-DC Converter with Energy Recovery Clamp and Reduced Circulating@aei.com Abstract - This paper introduces a full bridge converter with reduced circulating current and a reduction bridge converter operating at 32 kHz switching frequency. Losses and efficiency of the experimental

  18. A Fully Integrated Switched-Capacitor DC-DC Converter with Dual Output for Low Power Application

    E-Print Network [OSTI]

    Ayers, Joseph

    . The entire converter system uses two 2-to-1 converter blocks. The upper output voltage (3.2V) is generated from the 2-to-1_up converter by means of averaging the 5V input and the generated lower output voltage is designed using high-voltage 0.35m BCDMOS technology. Both output voltages are regulated by means of pulse

  19. Computer-Aided Optimization of dc/dc Converters for Automotive Applications Timothy C. Neugebauer David J. Perreault

    E-Print Network [OSTI]

    Perreault, Dave

    Computer-Aided Optimization of dc/dc Converters for Automotive Applications Timothy C. Neugebauer/dc converters, with a focus on converters for dual-voltage automotive electrical systems. A new CAD optimization is the next evolutionary step for automotive electrical systems. High-power loads will be moved to a new high

  20. Methodology for determining feasibility and cost for converting dredged material to topsoil 

    E-Print Network [OSTI]

    Graalum, Sara Jo Ann

    1997-01-01

    ). The purpose of this thesis is to discuss the applicability of converting dredged material to topsoil as a beneficial use of dredged material. The site selection in terms of location, material, and marketing are paramount in determining the most economically...

  1. Design of ultra low power analog-to-digital converter for ambulatory EEG recording

    E-Print Network [OSTI]

    El-Damak, Dina Reda

    2012-01-01

    Portable acquisition of biopotential signals requires the design of compact, energy efficient circuits and systems. Such systems typically include analog-to-digital converter for digitizing signals from AFE and feeding it ...

  2. Wavelength tunable polarization mode converter utilizing static strain effects in lithium niobate 

    E-Print Network [OSTI]

    Kwon, Ojin

    1999-01-01

    Electro-optically tunable polarization mode converters have been produced in LiNbO? substrate using all static strain optic effects. Maximum conversion efficiency of 98.3% was achieved at 66414m wavelength in TE to TM ...

  3. A 3-phase AC to AC matrix converter using the Venturini method 

    E-Print Network [OSTI]

    Dabbousi, Rami M. Osama

    2002-01-01

    flow, as well as sinusoidal currents and voltages in both input and output, with a reduction in the harmonics usually associated with converters. Therefore, this report discusses and analyzes all of the above characteristics, as well...

  4. Quantification of the influence of directional sea state parameters over the performances of wave energy converters 

    E-Print Network [OSTI]

    Pascal, Remy Claude Rene

    2012-11-29

    Accurate predictions of the annual energy yield from wave energy converters are essential to the development of the wave industry. The current method based on power matrices uses only a small part of the data available ...

  5. t is 2030, and a fleet of ten Gulfstream business jets have been converted to a

    E-Print Network [OSTI]

    Chen, Yiling

    I t is 2030, and a fleet of ten Gulfstream business jets have been converted to a new purpose concept of cooling the world by deflecting sunlight.UnlikejournalistEliKintisch's2010 book Hack the Planet

  6. Reliability Assessment of Fault-Tolerant Dc-Dc Converters for Photovoltaic Applications

    E-Print Network [OSTI]

    Liberzon, Daniel

    Reliability Assessment of Fault-Tolerant Dc-Dc Converters for Photovoltaic Applications Sairaj V in photovoltaic energy processing applications is presented. The proposed approach acknowledges the influence through several case studies. Index Terms-- Markov reliability modeling, photovoltaic systems, power

  7. Design of Wavelength Converting Switches for Optical Burst Jeyashankher Ramamirtham and Jonathan Turner

    E-Print Network [OSTI]

    Design of Wavelength Converting Switches for Optical Burst Switching Jeyashankher Ramamirtham Switches for Optical Burst Switching£ Jeyashankher Ramamirtham, Jonathan TurnerÝ Abstract Optical Burst Switching (OBS) is an experimental network technology that enables the construction of very high capacity

  8. Request for Information Regarding a Proposed Funding Opportunity for Administration of the Wave Energy Converter Prize

    Broader source: Energy.gov [DOE]

    This announcement is intended to serve as a Notice of Intent of the upcoming Funding Opportunity Announcement (FOA) regarding Administration of the Wave Energy Converter (WEC) Prize and Request for Information to solicit information regarding pote

  9. Request for Information Regarding a Proposed Funding Opportunity for Administration of the Wave Energy Converter Prize

    Broader source: Energy.gov [DOE]

    This announcement is intended to serve as a Notice of Intent of the upcoming Funding Opportunity Announcement (FOA) regarding Administration of the Wave Energy Converter (WEC) Prize and Request for Information.

  10. Design of a very high frequency resonant boost DC-DC converter

    E-Print Network [OSTI]

    Burkhart, Justin (Justin Michael)

    2010-01-01

    THIS thesis explores the development of a very high frequency DC-DC resonant boost converter. The topology examined features low parts count and fast transient response but suffers from higher device stresses compared to ...

  11. Improving the control strategy for a four-switch buck-boost converter

    E-Print Network [OSTI]

    Whitaker, Michael Peter

    2007-01-01

    The four-switch buck-boost converter, such as implemented with the Linear Technology LTC3440 integrated circuit, is useful in many applications. While this topology can be highly efficient, new strategies for controlling ...

  12. Design of a Very High Frequency dc-dc boost converter

    E-Print Network [OSTI]

    Sagneri, Anthony (Anthony David)

    2007-01-01

    Passive component volume is a perennial concern in power conversion. With new circuit architectures operating at extreme high frequencies it becomes possible to miniaturize the passive components needed for a power converter, ...

  13. Design and evaluation of a very high frequency dc/dc converter

    E-Print Network [OSTI]

    Pilawa-Podgurski, Robert C. N

    2007-01-01

    This thesis presents a resonant boost topology suitable for very high frequency (VHF, 30-300 MHz) dc-dc power conversion. The proposed design is a fixed frequency, fixed duty ratio resonant converter featuring low device ...

  14. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    with controlled motion. Power from sea waves, pages 381–399,SAN DIEGO Power Maximization in Wave-Energy Converters Usingfor wave energy con- verters with limited power takeoff

  15. Effect of a nonlinear power take off on a wave energy converter 

    E-Print Network [OSTI]

    Bailey, Helen Louise

    2011-11-22

    This thesis is titled The influence of a nonlinear Power Take Off on a Wave Energy Converter. It looks at the effect that having a nonlinear Power Take Off (PTO) has on an inertial referenced, slack moored, point absorber, ...

  16. Energy harvesting in silicon wavelength converters Kevin K. Tsia, Sasan Fathpour, and Bahram Jalali

    E-Print Network [OSTI]

    Jalali. Bahram

    ://www.ee.ucla.edu/~oecs/ Abstract: Nonlinear loss is the central problem in silicon devices that operate using nonlinear optical report the first demonstration of nonlinear photovoltaic effect in silicon wavelength converters

  17. Process for Converting Waste Glass Fiber into Value-Added Products

    Broader source: Energy.gov [DOE]

    Solid wastes are generated at glass fiber manufacturing facilities. With the help of a grant from DOE’s Inventions and Innovation Program, Albacem, LLC, developed a new process that converts these...

  18. The Utilization and Recovery of Energy from Blast Furnaces and Converters 

    E-Print Network [OSTI]

    Hegemann, K. R.; Niess, T.; Baare, R. D.

    1979-01-01

    comprising a gas cleaning unit for dust removal and a turbine for converting the recoverable thermal energy into mechanical and electrical energy. The adjustable annular gap scrubber for separating fine dust also serves as an element for regulating the gas...

  19. Converting Hybrid Wire-frames to B-rep Models Jie-Hui Gong

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Converting Hybrid Wire-frames to B-rep Models Jie-Hui Gong Dept. of Comp. Sci. and Technol of curved surfaces [Liu et al. 2001; Gong et al. 2006b]. The CSG oriented approach, however, is generally

  20. Design and Control of a Floating Wave-Energy Converter Utilizing a Permanent Magnet Linear Generator

    E-Print Network [OSTI]

    Tom, Nathan Michael

    2013-01-01

    electrical generator technology for wave energy converters,”seen, clean technologies, such as ocean wave energy, presentwave energy point absorber,” Proceedings of the IFAC Conference on Control Methodologies and Technology

  1. Radio frequency dc-dc converters : device characterization, topology evaluation, and design

    E-Print Network [OSTI]

    Leitermann, Olivia

    2008-01-01

    High frequency power conversion is attractive for the opportunities it affords for improved performance. Dc-dc converters operating at high frequencies use smaller-valued energy storage elements, which tend to be physically ...

  2. Impedance Control Network Resonant dc-dc Converter for Wide-Range High-Efficiency Operation

    E-Print Network [OSTI]

    Lu, Jie

    This paper introduces a new resonant converter architecture that utilizes multiple inverters and a lossless impedance control network (ICN) to maintain zero voltage switching (ZVS) and near zero current switching (ZCS) ...

  3. Development of an isolated flyback converter employing boundary-mode operation and magnetic flux sensing feedback

    E-Print Network [OSTI]

    Kenia, Mayur V. (Mayur Vasant), 1981-

    2004-01-01

    This thesis focuses on the marriage of magnetic-flux-sensing feedback and boundary-mode operation in a flyback converter to create a simple, small, low-cost, isolated, and tightly regulated power supply. Although each ...

  4. Soft-Switching High-Frequency AC-Link Universal Power Converters with Galvanic Isolation 

    E-Print Network [OSTI]

    Amirabadi, Mahshid

    2013-08-07

    be used in a variety of applications, including photovoltaic power generation, wind power generation, and electric vehicles. In these converters the link current and voltage are both alternating and their frequency can be high, which leads...

  5. A Dual-Supply Buck Converter with Improved Light-Load Efficiency 

    E-Print Network [OSTI]

    Zhang, Chao

    2012-07-16

    Power consumption and device size have been placed at the primary concerns for battery-operated portable applications. Switching converters gain popularity in powering portable devices due to their high efficiency, compact sizes and high current...

  6. Design and analysis of multiphase DC-DC converters with coupled inductors 

    E-Print Network [OSTI]

    Shi, Meng

    2007-09-17

    , directly coupled inductors have the benefit of low sensitivity to input variation at high frequencies. In addition, the proposed new structure for multiphase DC-DC converters has excellent current sharing performance and reduced current ripple. Computer...

  7. High Gain Transformerless DC-DC Converters for Renewable Energy Sources 

    E-Print Network [OSTI]

    Denniston, Nicholas Aaron

    2011-08-08

    Renewable energy sources including photovoltaic cells, fuel cells, and wind turbines require converters with high voltage gain in order to interface with power transmission and distribution networks. These conversions are conventionally made using...

  8. Nyquist-Rate Switched-Capacitor Analog-to-Digital Converters 

    E-Print Network [OSTI]

    Larsson, Andreas 1978-

    2012-11-28

    The miniaturization and digitization of modern microelectronic systems have made Analog-to-Digital converters (ADC) key building components in many applications. Internet and entertainment technologies demand higher and ...

  9. Frequency-based current-sharing techniques for paralleled power converters

    E-Print Network [OSTI]

    Perreault, David J.

    A new current-sharing technique for paralleled power converters, which is based on frequency encoding of the current-sharing information, is introduced. The approach has significant advantages over existing methods, including ...

  10. Predictive Power Control of Doubly-Fed Induction Generator for Wave Energy Converters

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Energy Converter Control Main Circuit Breaker Medium Voltage Switchgear Line Coupling Transformer Gear Medium Voltage Switchgear Line Coupling Transformer Fig. 1. An illustrative example of DFIG-based WEC

  11. Frequency selective analog to digital converter design : optimality, fundamental limitations, and performance bounds

    E-Print Network [OSTI]

    Osqui, Mitra M., 1980-

    2013-01-01

    In this thesis, the problem of analysis and design of Analog to Digital Converters (ADCs) is studied within an optimal feedback control framework. A general ADC is modeled as a causal, discrete-time dynamical system with ...

  12. Behavioral modeling and digital calibration of pipeline analog to digital converters 

    E-Print Network [OSTI]

    Bilhan, Erkan

    2001-01-01

    This research focuses on digital calibration of pipeline analog to digital converters (ADCs) and also modeling of error sources and design parameters of pipeline ADCs. Modern applications such as communications systems require high resolution ADCs...

  13. Zero-Crossing-Based Ultra-Low-Power A/D Converters

    E-Print Network [OSTI]

    Lee, Hae-Seung

    Since the first demonstration of a comparator-based switched-capacitor circuit, analog-to-digital (A/D) converters based on virtual ground detection have made steady and significant progress. Comparators have been replaced ...

  14. A New Integrated Onboard Charger and Accessory Power Converter for Plug-in Electric Vehicles

    SciTech Connect (OSTI)

    Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

    2014-01-01

    In this paper, a new approach is presented for integrating the function of onboard battery charging into the traction drive system and accessory dc-dc converter of a plug-in electric vehicle (PEV). The idea is to utilize the segmented traction drive system of a PEV as the frond converter of the charging circuit and the transformer and high voltage converter of the 14 V accessory dc-dc converter to form a galvanically isolated onboard charger. Moreover, a control method is presented for suppressing the battery current ripple component of twice the grid frequency with the reduced dc bus capacitor in the segmented inverter. The resultant integrated charger has lower cost, weight, and volume than a standalone charger due to a substantially reduced component count. The proposed integrated charger topology was verified by modeling and experimental results on a 5.8 kW charger prototype.

  15. Two U.S. University Research Reactors to be Converted From Highly...

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

    of Energy (DOE) has begun to convert research reactors from using highly-enriched uranium (HEU) to low-enriched uranium fuel (LEU) at the University of Florida and Texas A&M...

  16. Design and Control of a Floating Wave-Energy Converter Utilizing a Permanent Magnet Linear Generator

    E-Print Network [OSTI]

    Tom, Nathan Michael

    2013-01-01

    electrical generator technology for wave energy converters,”wave energy point absorber,” Proceedings of the IFAC Conference on Control Methodologies and Technologyseen, clean technologies, such as ocean wave energy, present

  17. Area Efficient D/A Converters For Accurate DC Operation Brandon Royce Greenley

    E-Print Network [OSTI]

    Moon, Un-Ku

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 6.2 Mismatch Modeling For Area Optimization . . . . . . . . . . . . . . . . . . . . . . . 51 6Area Efficient D/A Converters For Accurate DC Operation by Brandon Royce Greenley A THESIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 5.1 Measurement Setup

  18. Compact self-contained electrical-to-optical converter/transmitter

    DOE Patents [OSTI]

    Seligmann, D.A.; Moss, W.C.; Valk, T.C.; Conder, A.D.

    1995-11-21

    A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch. 13 figs.

  19. Compact self-contained electrical-to-optical converter/transmitter

    DOE Patents [OSTI]

    Seligmann, Daniel A. (Manteca, CA); Moss, William C. (San Mateo, CA); Valk, Theodore C. (Livermore, CA); Conder, Alan D. (Tracy, CA)

    1995-01-01

    A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch.

  20. An 8-bit current mode ripple folding analog to digital converter 

    E-Print Network [OSTI]

    Dinc, Huseyin

    2002-01-01

    Design of an 8-bit current mode, ripple-folding analog to digital (A/D) converter is discussed. The ripple folding technique and the possible implementations in different process technologies are summarized. To have an A/D ...