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Office of Scientific and Technical Information
Analysis of Harmonic Distortion Levels in Commercial Buildings
Science Conference Proceedings (OSTI)
This case study describes harmonic distortion concerns for commercial buildings and presents a method for evaluating these concerns based on typical load characteristics.
Power frequency communication on long feeders and high levels of harmonic distortion
SciTech Connect
TWACS is a unique Power Frequency Communication (PFC) technology. The power voltage is modulated at the substation bus for outbound communication and inbound communication from a remote transponder is accomplished by drawing precisely controlled current pulses which are detectable at the distribution substation. The propagation characteristics of the TWACS signal and the frequency characteristics of the signal detector make it possible to communicate over very long distribution feeders and provide a high degree of immunity against harmonic distortions of the power system voltage and current.
Mak, S.T.; Maginnis, R.L. [Distribution Control Systems, Inc., Hazelwood, MO (United States)
Watthour meter accuracy under controlled unbalanced harmonic voltage and current conditions
This work presents the results of phase 1 of the project on the accuracy of watthour meters when subjected to closely-duplicated real-world unbalanced harmonic voltage and current conditions. Such real-world conditions involved differences in voltage and current magnitudes as well as differences in the voltage and current total harmonic distortion levels of each phase. Tests were performed on a selected sample of nine three-phase and three single-phase watthour meters. Some results showed that under a particular set of unbalanced waveforms with harmonic conditions of I{sub THD} > 80% and V{sub THD} > 2%, the percentage errors exhibited by these meters ranged from {minus}10.09% to +0.52%.
Domijan, A. Jr.; Embriz-Santander, E.; Gilani, A. [Univ. of Florida, Gainesville, FL (United States). Dept. of Electrical Engineering; Lamer, G.; Stiles, C.; Williams, C.W. Jr. [Florida Power Corp., St. Petersburg, FL (United States)
Joint estimation and correction of geometric distortions for EPI functional MRI using harmonic retrieval
E-Print Network (OSTI)
Magnetic resonance imaging (MRI) uses applied spatial variations in the magnetic field to encode spatial position. Therefore, nonuniformities in the main magnetic field can cause image distortions. In order to correct the ...
Nguyen, Hien M.
Electric Power Waveform Distortion
Engineering issues regarding waveform distortion, harmonics, radio-frequency noise, and similar concerns have existed as long as there has been a power industry. These deal with consequences ranging from heating of transformers and machinery to telephone and radio interference. While waveform distortion has been around for a long time, the sources of harmonics and electromagnetic noise owned by the electricity customer have proliferated in recent years with the widespread usage of such things as switchin...
Distributed Generation Source Stiffness and Its Impact on Voltage Distortion
Distributed generators with loads that create high harmonics can cause excessive voltage distortion. This report's objective was to evaluate under controlled laboratory conditions voltage distortion resulting from application of nonlinear load for three different types of rotary generators and one inverter-based generator. Test results also were used to verify the analytical model for predicting voltage distortion from nonlinear load application.
PRE-SW Grid-IQ Harmonics Evaluation Module - Prototype
The application provides a user-friendly interface that would be used to perform harmonic analysis such as conducting frequency scans and harmonic distortion analysis by allowing user to select the ...
Power Quality Hotline Call-of-the-Month for August 2009: Voltage Harmonics, Part 1: Fundamentals
This Call of the Month discusses what harmonics are and how they're produced. Part 2 will address the equipment concerns related to the presence of high levels of harmonic distortion in a customer's service voltage.
Efficient hybrid shunt active power filter for improvement of power factor and harmonic suppression using MATLAB
Power quality management is the main problem that the industry is facing today. This is mainly affected by the generation of harmonics. The growing use of electronic equipment produces a large amount of harmonics in distribution systems because of non-sinusoidal ... Keywords: MATLAB 7.6, harmonic suppression, hybrid filter, power quality, shunt active power filter, total harmonic distortion
Jarupula Somlal
LCA Harmonization
Open Energy Info (EERE)
Loading... Loading... About Box & Whisker Scatter Data References Publications Definitions definitions LCA Harmonization The Life Cycle Assessment (LCA) Harmonization project systematically reviewed estimates of life cycle GHG emissions from electricity generation technologies published between 1970 and 2010. LCAs consider emissions from all stages in the life cycle of an electricity generation technology, from component manufacturing, to operation of the generation facility to its decommissioning, and including acquisition, processing and transport of any required fuels. For selected technologies, a meta-analytical procedure called "harmonization" was applied to adjust estimates so that they were methodologically more consistent and therefore more comparable. This
Harmonics from SVC transformer saturation with direct current offset
Circulation of direct current in transformer windings can cause significant transformer saturation and harmonic generation. This problem may be experienced by static var compensators with anti-parallel thyristor arrangement. This paper presents a technique to analyze the harmonic distortions caused by transformer saturation with direct current offset. The technique is used to investigate the harmonic generation from the transformer of a static var compensator to be installed in the B.C. Hydro system.
Xu, W.; Martinich, T.G.; Sawada, J.H.; Mansour, Y. (British Columbia Hydro, Burnaby, British Columbia (Canada))
Harmonic engine
A high efficiency harmonic engine based on a resonantly reciprocating piston expander that extracts work from heat and pressurizes working fluid in a reciprocating piston compressor. The engine preferably includes harmonic oscillator valves capable of oscillating at a resonant frequency for controlling the flow of working fluid into and out of the expander, and also preferably includes a shunt line connecting an expansion chamber of the expander to a buffer chamber of the expander for minimizing pressure variations in the fluidic circuit of the engine. The engine is especially designed to operate with very high temperature input to the expander and very low temperature input to the compressor, to produce very high thermal conversion efficiency.
Bennett, Charles L. (Livermore, CA)
Optical distortions in electron/positron storage rings
We have studied the optical distortions in the PEP electron/positron storage ring for various optical configurations using the computer programs DIMAT, HARMON, PATRICIA, and TURTLE. The results are shown graphically by tracing several thousand trajectories from one interaction region to the next using TURTLE and by tracing a few selected rays several hundred turns using the programs DIMAT and PATRICIA. The results show an interesting correlation between the calculated optical cleanliness of a particular lattice configuration and the observed operating characteristics of the machine.
Brown, K.L.; Donald, M.; Servranckx, R.
Globally Optimal Estimation of Nonrigid Image Distortion
Image alignment in the presence of non-rigid distortions is a challenging task. Typically, this involves estimating the parameters of a dense deformation field that warps a distorted image back to its undistorted template. Generative approaches based ... Keywords: Combine generative and discriminative approaches, Computer vision, Distortion estimation, Feature correspondence, Global optimum, Image alignment, Image registration, Iterative approach, Motion and tracking, Nonrigid deformation, Physics-based vision, Water distortion
Yuandong Tian; Srinivasa G. Narasimhan
A Smart Recording Power Analyzer Prototype Using LabVIEW and Low-Cost Data Acquisition (DAQ) in Being a Smart Renewable Monitoring System
Nowadays, to indicate the quality of Thailand's existing power system including the newly-installed distributed renewable energy sources, a number of pricy power quality analyzers are being used in most areas. This article proposes an alternative of ... Keywords: Power Quality, LabVIEWTM, Data acquisition (DAQ), Total Harmonics Distortion (THD), Flickers, Smart grid, Renewable monitoring system (REMS)
Chow Chompoo-Inwai, Jade Mungkornassawakul
TMS320F2812 DSP controller for dynamic voltage restorer (DVR) application for improving of a three phase inverter
This paper discusses a control technique improvement of a three-phase inverter using TMS320F2812 DSP controller for Dynamic Voltage Restorer (DVR) applications. The output of the inverter is then connected to a voltage grid via a second order filter ... Keywords: TMS320F2812 DSP, dynamic voltage restorer (DVR), filter, inverters, total harmonic distortion (THD)
R. Omar; N. A. Rahim
Optimal Design of Integration of Intelligent, Adaptive Solar (PV) Power Generator with Grid for Domestic Energy Management System
This paper introduces a novel system based on integration of solar power generator with grid for optimal utilization of energy by minimizing the power drawn from grid. A prototype grid integrated PV system comprising of PV module (2*75Wp), battery bank ... Keywords: Solar power Generator (SPG), Domestic Energy Management, Bi-directional Inverter, Photovoltaic(PV), Total Harmonic Distortion (THD)
S. N. Singh; Pooja Singh; Swati Kumari; Swati
Harmonic voltages and currents on two Greek islands with photovoltaic stations: Study and field measurements
The purpose of this paper is to investigate the harmonic distortion present to the electric grid of two small Greek islands (Arki and Antikythera) where Photovoltaic Stations are installed, to study their inverters harmonic behavior and to present the measurements of the harmonic voltages and currents obtained at field tests on these two islands. It is shown that the harmonics injected by the Photovoltaic Stations to the electric grid are not very high and at most cases they can not cause significant problems to the appliances to he customers. On the other had, a theoretical analysis of the installed inverters technology is also presented, showing that the results from the measurements and those of the presented analysis are quite identical. From both measurements and theoretical analysis remarkable conclusions concerning the problem of harmonics are drawn.
Vokas, G.A.; Machias, A.V. [National Technical Univ., Athens (Greece). Electric Power Div.
Inlet distortion generation for a transonic compressor .
??A single-stage transonic research compressor and test rig are to be used to obtain data on the effect of inlet flow distortion on compressor (and� (more)
Papamarkos, Ioannis.
Harmonizing Above Code Codes
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
Harmonizing "Above Code" Harmonizing "Above Code" Codes Doug Lewin Executive Director, SPEER 6 Regional Energy Efficiency Organizations SPEER Members Texas grid facing an energy crisis * No new generation coming online * Old, inefficient coal-fired plants going offline * ERCOT CEO Trip Doggett said "We are very concerned about the significant drop in the reserve margin...we will be very tight on capacity next summer and have a repeat of this year's emergency procedures and conservation appeals." Higher codes needed to relieve pressure Building Codes are forcing change * 2012 IECC 30% higher than 2006 IECC * IRC, the "weaker code," will mirror IECC in 2012 * City governments advancing local codes with
Refractive shape from light field distortion
Acquiring transparent, refractive objects is challenging as these kinds of objects can only be observed by analyzing the distortion of reference background patterns. We present a new, single image approach to reconstructing ...
Wetzstein, Gordon
Harmonic generation at high intensities
Atomic electrons subject to intense laser fields can absorb many photons, leading either to multiphoton ionization or the emission of a single, energetic photon which can be a high multiple of the laser frequency. The latter process, high-order harmonic generation, has been observed experimentally using a range of laser wavelengths and intensities over the past several years. Harmonic generation spectra have a generic form: a steep decline for the low order harmonics, followed by a plateau extending to high harmonic order, and finally an abrupt cutoff beyond which no harmonics are discernible. During the plateau the harmonic production is a very weak function of the process order. Harmonic generation is a promising source of coherent, tunable radiation in the XUV to soft X-ray range which could have a variety of scientific and possibly technological applications. Its conversion from an interesting multiphoton phenomenon to a useful laboratory radiation source requires a complete understanding of both its microscopic and macroscopic aspects. We present some recent results on the response of single atoms at intensities relevant to the short pulse experiments. The calculations employ time-dependent methods, which we briefly review in the next section. Following that we discuss the behavior of the harmonics as a function of laser intensity. Two features are notable: the slow scaling of the harmonic intensities with laser intensity, and the rapid variation in the phase of the individual harmonics with respect to harmonic order. We then give a simple empirical formula that predicts the extent of the plateau for a given ionization potential, wavelength and intensity.
Schafer, K.J.; Krause, J.L.; Kulander, K.C.
LCA Harmonization | Open Energy Information
LCA Harmonization LCA Harmonization Jump to: navigation, search Tool Summary LAUNCH TOOL Name: LCA Harmonization Agency/Company /Organization: NREL Sector: Energy Focus Area: Greenhouse Gas Phase: Evaluate Options, Prepare a Plan Resource Type: Online calculator User Interface: Website Website: en.openei.org/apps/LCA/ Web Application Link: en.openei.org/apps/LCA/ Cost: Free OpenEI Keyword(s): Featured References: Background and Reflections on the Life Cycle Assessment Harmonization Project[1] National Renewable Energy Laboratory[2] The LCA Harmonization project systematically reviewed estimates of life cycle GHG emissions from electricity generation technologies published between 1970 and 2010. This application (app) allows for customized visualization of summary statistics and the underlying published estimates
Analysis and Design of New Harmonic Mitigation Approaches
Numerous approaches have been proposed in order to resolve the problems of current harmonics in electrical distribution systems. The rapid development of power semiconductors along with the revolutionary advances on microprocessors consolidated the motor drives industry and with it a massive proliferation of non-linear loads. It was thought that these very same technological advances would trigger an explosive development of harmonic solutions based on power electronics. Moreover, the introduction of the instantaneous active and reactive power theory or the so-called p, q theory which simplifies and gives more robustness to the control strategies of active filters reinforced this idea. Three decades have passed since the first IGBT was introduced in early 1980s, and active harmonic solutions are not the first choice to solve harmonic pollution in electrical distribution systems, mainly due to the high cost and the perception of low reliability. Given this scenario, in this work two main approaches are explored. First, the combination of an asymmetric 18-pulse rectifier with a reduced KVA active harmonic filter to improve the performance under abnormal utility conditions. Second, an interleaved active harmonic filter using multiple inverters connected in parallel at the ac and dc size, which will allow for higher power ratings and power density increase. The performance issues of the asymmetric 18-pulse rectifier under unbalanced voltage and pre-existing harmonic components are analyzed, as well as the current distortion improvement, achieved when an active power filter is introduced. On the other hand, the high frequency harmonic cancellation when interleaved inverters are used, the circulation of zero-sequence current and the impact of interleaving on dc bus capacitor are analyzed. Finally, some methods to mitigate the low frequency circulating currents based on eliminating the zero-sequence component, and the introduction of common mode inductors to reduce the high frequency circulating current are studied. Without a doubt the search for new cost-effective topologies able to reach broader power levels and voltage ranges will continue emerging giving more alternatives to users. Moreover, extensive research on wide band gap devices such as Silicon Carbide (SiC) and Gallium Nitride (GaN), with which it is possible to reach higher voltage breakdown and at least an order-of-magnitude lower switching losses, makes the future more promising for active solutions.
Aeloiza Matus, Eddy 1972-
Patent Harmonization: Creating Uniform Patent Laws
Patent Harmonization: Creating Uniform Patent Laws. David V. Radack. You may have seen or heard the phrase "patent harmonization" used when discussing�...
Noncontacting Laser Scanner for Fuel Assembly Distortion Measurement
The distortion of fuel assemblies and bundles due to in-reactor exposure is a problem that has the potential to significantly affect the operations of both BWRs and PWRs. The distortion can take many shapes of axial, lateral and torsional displacements, with common distortions manifested as bows (such as C, S, and W shapes). Such distortion has implications from fuel ...
Zigzag laser with reduced optical distortion
DOE Patents (OSTI)
The architecture of the present invention has been driven by the need to solve the beam quality problems inherent in Brewster's angle tipped slab lasers. The entrance and exit faces of a solid state slab laser are cut perpendicular with respect to the pump face, thus intrinsically eliminating distortion caused by the unpumped Brewster's angled faces. For a given zigzag angle, the residual distortions inherent in the remaining unpumped or lightly pumped ends may be reduced further by tailoring the pump intensity at these ends. 11 figures.
Albrecht, G.F.; Comaskey, B.; Sutton, S.B.
Boron abundance and solar neutrino spectrum distortion
The presence of neutrinos from Boron decay in the flux observed on Earth is attested by the observation of their energy spectrum. Possible distortions of the spectrum investigated in current detectors are often interpreted in terms of evidence in favour or against various schemes of neutrino oscillations. We stress here that a distortion of the spectrum at high energies could also result from an increase in the ratio of neutrinos originating from ($^3$He+p) and $^8$B reactions. While a $^8$B neutrino depletion would contribute to this effect, an increase in the Hep contribution seems also needed to reproduce the preliminary data.
R. Escribano; J. -M. Frere; A. Gevaert; D. Monderen
Harmonic oscillator and nuclear pseudospin
A generalized relativistic harmonic oscillator for spin 1/2 particles is studied. The Dirac Hamiltonian contains a scalar S and a vector V quadratic potentials in the radial coordinate
Ronai Lisboa; Manuel Malheiro; Antonio S. de Castro; Pedro Alberto; Manuel Fiolhais
Analyzing harmonic monitoring data using data mining
Harmonic monitoring has become an important tool for harmonic management in distribution systems. A comprehensive harmonic monitoring program has been designed and implemented on a typical electrical MV distribution system in Australia. The monitoring ... Keywords: classification, clustering, data mining, harmonics, monitoring system, power quality, segmentation
Ali Asheibi; David Stirling; Danny Soetanto
Harmonic analysis of electrical distribution systems
This report presents data pertaining to research on harmonics of electric power distribution systems. Harmonic data is presented on RMS and average measurements for determination of harmonics in buildings; fluorescent ballast; variable frequency drive; georator geosine harmonic data; uninterruptible power supply; delta-wye transformer; westinghouse suresine; liebert datawave; and active injection mode filter data.
Asymmetric Gaussian harmonic steering in second harmonic generation
We show that intracavity second harmonic generation can be a source of asymmetric Gaussian harmonic steering, which is adjustable by tuning the cavity loss rates at the fundamental and harmonic frequencies. Working in the semi-classical regime where the cavity is pumped at less than the self-pulsing intensity, we find that whether quantum steering is available via the standard measurements of the Einstein-Podolsky-Rosen correlations can depend on which quadrature measurements are inferred from output spectral measurements of the fundamental and the harmonic. Altering the ratios of the cavity loss rates can be used to tune the regions where symmetric steering is or is not available, with the results becoming asymmetric over all frequencies as the cavity damping at the fundamental frequency becomes significantly greater than that at the harmonic. This asymmetry and its functional dependence on frequency is a potential new tool for experimental quantum information science, with possible utility for quantum key distribution. Although we show the effect here for Gaussian measurements of the quadratures, and cannot rule out a return of the steering symmetry for some class of non-Gaussian measurements, we note here that the system obeys Gaussian statistics in the operating regime investigated and Gaussian inference is at least as accurate as any other method for calculating the necessary correlations.
M. K. Olsen
Cyclotron emission effect on CMB spectral distortions
We investigated the role of the cyclotron emission (CE) associated to cosmic magnetic fields (MF) on the evolution of cosmic microwave background (CMB) spectral distortions. We computed the photon and energy injection rates by including spontaneous and stimulated emission and absorption. These CE rates have been compared with those of bremsstrahlung (BR) and double Compton scattering (DC), for realistic CMB distorted spectra at various cosmic epochs. For reasonable MF strengths we found that the CE contribution to the evolution of the CMB spectrum is much smaller than the BR and DC contributions. The constraints on the energy exchanges at various redshifts can be then derived, under quite general assumptions, by considering only Compton scattering (CS), BR, and DC, other than the considered dissipation process. Upper limits to the CMB polarization degree induced by CE have been estimated.
Carlo Burigana; Andrea Zizzo
Fermion Quasi-Spherical Harmonics
Spherical Harmonics, $Y_\\ell^m(\\theta,\\phi)$, are derived and presented (in a Table) for half-odd-integer values of $\\ell$ and $m$. These functions are eigenfunctions of $L^2$ and $L_z$ written as differential operators in the spherical-polar angles, $\\theta$ and $\\phi$. The Fermion Spherical Harmonics are a new, scalar and angular-coordinate-dependent representation of fermion spin angular momentum. They have $4\\pi$ symmetry in the angle $\\phi$, and hence are not single-valued functions on the Euclidean unit sphere; they are double-valued functions on the sphere, or alternatively are interpreted as having a double-sphere as their domain.
G. Hunter; P. Ecimovic; I. Schlifer; I. M. Walker; D. Beamish; S. Donev; M. Kowalski; S. Arslan; S. Heck
Thermally induced wave-front distortions in laser windows
A simple analytical expression is given for wave-front distortions and birefringence due to heating in laser windows. (AIP)
Greninger, C.E.
Prony analysis for power system transient harmonics
Proliferation of nonlinear loads in power systems has increased harmonic pollution and deteriorated power quality. Not required to have prior knowledge of existing harmonics, Prony analysis detects frequencies, magnitudes, phases, and especially damping ...
Li Qi; Lewei Qian; Stephen Woodruff; David Cartes
The (n+1)-dimensional Harmonic Oscillator - CECM
The (n+1)-dimensional harmonic oscillator equation is of the form: i $\\displaystyle \\phi_{t}^{}$ = $\\displaystyle \
A high-performance fast switching charge dump assisted class-K* audio amplifier
A new Class-K* audio amplifier with high-power efficiency and high fidelity is integrated in a 0.35-�m CMOS process. It proposes a new topology connected Class-D amplifier with fast-switching charge-dump (FSCD) amplifier in parallel. The ... Keywords: Class-D, audio amplifier, class-AB, class-K, efficiency, fidelity, pulse-width-modulation (PWM), total harmonic distortion (THD) and CMOS
Kwang-Chan Lee; Chang-Seok Chae; Jin-Yong Jeon; Kang-Ho Lee; Gyu-Hyeong Cho
NREL: Energy Analysis: Life Cycle Assessment Harmonization
NLE Websites -- All DOE Office Websites (Extended Search)
Life Cycle Assessment Harmonization Life Cycle Assessment Harmonization Life cycle assessment (LCA) harmonization helps lenders, utility executives, and lawmakers get the best, most precise information on greenhouse gas emissions from various sources of energy. LCA has been used to estimate and compare GHG emissions from utility-scale power systems for three decades, often with considerable variability in results. Harmonization provides more exact estimates of greenhouse-gas emissions for renewable and conventional electricity generation technologies, clarifying inconsistent and conflicting estimates in the published literature and reducing uncertainty. Highlights of Recent Studies Chart that compares published and harmonized lifecycle greenhouse gas emissions. For help reading this chart, please contact the webmaster.
Prediction of Part Distortion in Die Casting
The die casting process is one of the net shape manufacturing techniques and is widely used to produce high production castings with tight tolerances for many industries. An understanding of the stress distribution and the deformation pattern of parts produced by die casting will result in less deviation from the part design specification, a better die design and eventually more productivity and cost savings. This report presents methods that can be used to simulate the die casting process in order to predict the deformation and stresses in the produced part and assesses the degree to which distortion modeling is practical for die casting at the current time. A coupled thermal-mechanical finite elements model was used to simulate the die casting process. The simulation models the effect of thermal and mechanical interaction between the casting and the die. It also includes the temperature dependant material properties of the casting. Based on a designed experiment, a sensitivity analysis was conducted on the model to investigate the effect of key factors. These factors include the casting material model, material properties and thermal interaction between casting and dies. To verify the casting distortion predictions, it was compared against the measured dimensions of produced parts. The comparison included dimensions along and across the parting plane and the flatness of one surface.
R. Allen Miller
Lattice Distortion Formations by Low Energy Ar+ Bombardment of ...
The intensity distribution consists of two maxima, one from the distorted layer ... Deformation Behavior of Nanocrystalline Co Measured by High-energy X-ray�...
Chemical Consequences of Heme Distortion and the Role of Heme Distortion in Signal Transduction of H-NOX Proteins
Chemical Consequences of Heme Distortion and the Role ofMatthew B. Francis Spring 2010 Chemical Consequences of Hemeby Charles Olea, Jr. Abstract Chemical Consequences of Heme
Olea, Jr., Charles
Improving Clinical Laboratory Testing through Harmonization ...
... involvement in harmonizing this category of clinical laboratory testing procedures. ... patients at risk from non-standardized laboratory test results and ...
Harmonization of Federal and International Regulations | Department...
and International Regulations Update of the U.S. Department of Transportation (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA). Harmonization of Federal and...
On distorted probabilities and m-separable fuzzy measures
Fuzzy measures are used in conjunction with fuzzy integrals for aggregation. Their role in the aggregation is to permit the user to express the importance of the information sources (either criteria or experts). Due to the fact that fuzzy measures are ... Keywords: Distorted probabilities, Fuzzy measures, m-Dimensional distorted probabilities, m-Symmetric fuzzy measures
Yasuo Narukawa; Vicen� Torra
Impact of stray capacitance on hvdc harmonics
Recent experience suggests that a new approach is needed to determining harmonic generation from hvdc converters for the purpose of telephone interference evaluation. This paper presents simulation results showing the effect on harmonic generation of stray capacitances inherent to hvdc converters. These simulation results illustrate the basic characteristics of the phenomenon, which agree qualitatively with field experience.
Larsen, E.V.; Sublich, M.; Kapoor, S.C.
Building Technologies Office: Harmonization of Wireless Dimming Lighting
Harmonization of Harmonization of Wireless Dimming Lighting Controls Research Project to someone by E-mail Share Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on Facebook Tweet about Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on Twitter Bookmark Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on Google Bookmark Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on Delicious Rank Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on Digg Find More places to share Building Technologies Office: Harmonization of Wireless Dimming Lighting Controls Research Project on
Achieving the Gaussian Rate-Distortion Function by Prediction
The "water-filling" solution for the quadratic rate-distortion function of a stationary Gaussian source is given in terms of its power spectrum. This formula naturally lends itself to a frequency domain "test-channel" realization. We provide an alternative time-domain realization for the rate-distortion function, based on linear prediction. This solution has some interesting implications, including the optimality at all distortion levels of pre/post filtered vector-quantized differential pulse code modulation (DPCM), and a duality relationship with decision-feedback equalization (DFE) for inter-symbol interference (ISI) channels.
Zamir, Ram; Erez, Uri
Fast distortion measurement using chord-length parameterisation within the vertex-based rate-distortion optimal shape coding framework
Existing vertex-based operational rate-distortion (ORD) optimal shape coding algorithms use the shortest absolute distance (SAD) or alternatively either the distortion band (DB) or tolerance band (TB) as their distortion measuring technique. Each approach however can lead to inaccurate distortion measurements, though these can be avoided by employing the accurate distortion measurement technique for shape coding (ADMSC). From a computational time 2 O N time for DB and TB for both polygon and B-spline based encoding, perspective, an N point contour requires () 2 while SAD and ADMSC incur order O ( N) time for polygonal encoding, but ( N) O complexity for B-spline based encoding, thereby rendering ORD optimal algorithms computationally inefficient. This paper presents a novel distortion measurement strategy based on chord-length parameterisation (DMCLP) of a boundary that incurs order O ( N) complexity for both polygon and B-spline based encoding, while preserving an analogous rate-distortion performance to the original ORD optimal shape coding algorithms, when it is embedded within the ORD framework. I.
Ferdous A. Sohel; Gour C. Karmakar; Laurence S. Dooley
Harmonization of Federal and International Regulations
DOT/PHMSA DOT/PHMSA Update Michael Conroy U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Office of Hazardous Materials Safety Radioactive Materials - 2 - HM-230 (1/26/04) Harmonized with 2000 Version of IAEA's 1996 Edition - 3 - Changes to the IAEA Regulations Since 2000 2003 Amendment 2005 Edition 2009 Edition U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration Harmonization Rulemaking (HM-250) * Harmonize with 2009 Edition of TS-R-1 * Miscellaneous Other Fixes - Update, clarify, correct, or provide relief from certain regulatory requirements * DOT and NRC will both issue rulemakings - DOT NPRM Issued August 12, 2011 - NRC NPRM coming soon
Preliminary mode distortion measurements on the Jefferson Lab IRFEL
We previously reported analytical calculations of mirror distortion in a high power FEL with a near-concentric cavity. Naive assumptions about the FEL power vs. distortion led us to believe that mirror losses were much lower than expected. Recently we have directly measured the mode size and beam quality as a function of power using a resonator with a center wavelength of 5 microns. The resonator mirrors were calcium fluoride. This material exhibits a large amount of distortion for a given power but, due to the negative slope of refractive index v temperature, adds almost no optical phase distortion on the laser output. The mode in the cavity can thus be directly calculated from the measurements at the resonator output. The presence of angular jitter produced results inconsistent with cold cavity expectations. Removing the effects of the angular jitter produces results in reasonable agreement with analytical models assuming mirror losses comparable to the original expectations.
Stephen V. Benson; Joe Gubeli; Michelle D. Shinn
The Effect of Inlet Flow Profile Distortion on Fan Performance
Performance tests on fans for utility and industrial applications are based on codes that expect a relatively uniform velocity profile at the fan inlet. Unfortunately, when fans scaled up from the ideal model fans are installed in actual utility and industrial applications, non-uniform or distorted flow patterns often occur at the inlet of the fan. This project sought to determine and, if possible, quantify the effect on fan performance of distorted inlet flow profiles. A second goal was to determine whe...
Sliding-mode amplitude control techniques for harmonic oscillators
This thesis investigates both theoretical and implementation-level aspects of switching- feedback control strategies for the development of voltage-controlled oscillators. We use a modified sliding-mode compensation scheme based on various norms of the system state to achieve amplitude control for wide-tuning range oscillators. The proposed controller provides amplitude control at minimal cost in area and power consumption. Verification of our theory is achieved with the physical realization of an amplitude controlled negative-Gm LC oscillator. A wide-tuning range RF ring oscillator is developed and simulated, showing the effectiveness of our methods for high speed oscillators. The resulting ring oscillator produces an amplitude controlled sinusoidal signal operating at frequencies ranging from 170 MHz to 2.1 GHz. Total harmonic distortion is maintained below 0:8% for an oscillation amplitude of 2 Vpp over the entire tuning range. Phase noise is measured as -105.6 dBc/Hz at 1.135 GHz with a 1 MHz offset.
Marquart, Chad A.
NREL: Energy Analysis - Life Cycle Assessment Harmonization
Life Cycle Assessment Harmonization Life Cycle Assessment Harmonization Life Cycle Greenhouse Gas Emissions from Electricity Generation (Fact Sheet) Cover of the Life Cycle Greenhouse Gas Emissions from Electricity Generation factsheet Download the Fact Sheet The U.S. Department of Energy enlisted NREL to review and "harmonize" life cycle assessments (LCA) of electricity generation technologies. Hundreds of assessments have been published, often with considerable variability in results. These variations in approach, while usually legitimate, hamper comparison across studies and pooling of published results. Learn more about life cycle assessments of energy technologies. By harmonizing this data, NREL seeks to reduce the uncertainty around estimates for environmental impacts of renewables and increase the value of
Second Harmonic Resonance for Equatorial Waves
Simple, exact analytical conditions for second harmonic resonance between equatorial waves are derived. Such resonance can occur only between two Rossby waves or two westward travelling gravity waves. It is shown that regardless of whether the ...
John P. Boyd
Nonlinear harmonic modeling of phemt devices for increased power amplifier efficiencies
This thesis is a comprehensive study of how harmonic terminations can greatly increase a power amplifier's efficiency (PAE). To show this improvement, the PHEMT amplifier is biased in the low noise region of operation (L, = 20 mA, Vd, = 3 V) and operated at a frequency of 2.2 GHz. An attempt is made to generate a working model which characterizes the amplifier's performance with and without harmonic termination. Both measured and modeled data are compared in order to verify the model's performance. Once a working model is realized, the designing of an amplifier can be done by simulation without the cumbersome task of taking measurements. The measured data is obtained using an electronic load pull system which is capable of rapid data acquisition. This study shows that when harmonic termination is used, the PAE can improve in some cases by about 15 % depending upon the operating conditions of the device. This improved PA-E can result in longer operational lifetimes of devices such as cellular phones and reduce the size of these units. Longer lifetimes are extremely important especially for space applications where replacement of power supplies is very costly. Power measurements as well as relevant intermodulation distortion measurements are also done for Class A and Class B operation in order to show the advantages and disadvantages of each.
Strassner, Bernd Herbert
Dual aperture dipole magnet with second harmonic component
An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.
Praeg, W.F.
Praeg, Walter F. (Palos Park, IL)
Approximate Coulomb distortion effects in (e,e'p) reactions
In this paper we apply a well-tested approximation of electron Coulomb distortion effects to the exclusive reaction (e,e'p) in the quasielastic region. We compare the approximate treatment of Coulomb distortion effects to the exact distorted wave Born approximation evaluated by means of partial wave analysis to gauge the quality of our approximate treatment. We show that the approximate M\\"oller potential has a plane-wave-like structure and hence permits the separation of the cross section into five terms which depend on bilinear products of transforms of the transition four current elements. These transforms reduce to Fourier transforms when Coulomb distortion is not present, but become modified with the inclusion of Coulomb distortion. We investigate the application of the approximate formalism to a model of 208Pb(e,e'p) using Dirac-Hartree single particle wave functions for the ground state and relativistic optical model wave functions for the continuum proton. We show that it is still possible to extract, albeit with some approximation, the various structure functions from the experimentally measured data even for heavy nuclei.
K. S. Kim; L. E. Wright
A Hydrodynamical Approach to CMB mu-distortions
Spectral distortion of the cosmic microwave background provides a unique opportunity to probe primordial perturbations on very small scales by performing large-scale measurements. We discuss in a systematic and pedagogic way all the relevant physical phenomena involved in the production and evolution of the mu-type spectral distortion. Our main results agree with previous estimates (in particular we show that a recently found factor of 3/4 arises from relativistic corrections to the wave energy). We also discuss several subleading corrections such as adiabatic cooling and the effects of bulk viscosity, baryon loading and photon heat conduction. Finally we calculate the transfer function for mu-distortions between the end of the mu-era and now.
Enrico Pajer; Matias Zaldarriaga
High harmonic phase in molecular nitrogen
Electronic structure in atoms and molecules modulates the amplitude and phase of high harmonic generation (HHG). We report measurements of the high harmonic spectral amplitude and phase in N{sub 2}. The phase is measured interferometrically by beating the N{sub 2} harmonics with those of an Ar reference oscillator in a gas mixture. A rapid phase shift of 0.2{pi} is observed in the vicinity of the HHG spectral minimum, where a shift of {pi} had been presumed [J. Itatani et al., Nature 432, 867 (2004)]. We compare the phase measurements to a simulation of the HHG recombination step in N{sub 2} that is based on a simple interference model. The results of the simulation suggest that modifications beyond the simple interference model are needed to explain HHG spectra in molecules.
McFarland, Brian K.
Harmonic Analysis Errors in Calculating Dipole,
Harmonic Analysis Errors in Calculating Dipole, Harmonic Analysis Errors in Calculating Dipole, Quadrupole, and Sextupole Magnets using POISSON Ro be rt J. La ri<::::R~ i. September 10, 1985 Introduction LS-32 The computer program POISSON was used to calculate the dipole, quadru- pole, and sextupole magnets of the 6 GeV electron storage ring. A trinagular mesh must first be generated by LATTICE. The triangle size is varied over the "universe" at the discretion of the user. This note describes a series of test calculations that were made to help the user decide on the size of the mesh to reduce the harmonic field calculation errors. A conformal transfor- mation of a multipole magnet into a dipole reduces these errors. Dipole Magnet Calculations A triangular mesh used to calculate a "perfect" dipole magnet is shown in
The evolution of CMB spectral distortions in the early Universe
The energy spectrum of the cosmic microwave background (CMB) allows constraining episodes of energy release in the early Universe. In this paper we revisit and refine the computations of the cosmological thermalization problem. For this purpose a new code, called CosmoTherm, was developed that allows solving the coupled photon-electron Boltzmann equation in the expanding, isotropic Universe for small spectral distortion in the CMB. We explicitly compute the shape of the spectral distortions caused by energy release due to (i) annihilating dark matter; (ii) decaying relict particles; (iii) dissipation of acoustic waves; and (iv) quasi-instantaneous heating. We also demonstrate that (v) the continuous interaction of CMB photons with adiabatically cooling non-relativistic electrons and baryons causes a negative mu-type CMB spectral distortion of DI_nu/I_nu ~ 10^{-8} in the GHz spectral band. We solve the thermalization problem including improved approximations for the double Compton and Bremsstrahlung emissivities, as well as the latest treatment of the cosmological recombination process. At redshifts z injection because of (ii) and (iv) Pixie should allow to improve existing limits, while the CMB distortions caused by the other processes seem to remain unobservable with the currently proposed sensitivities and spectral bands of Pixie.
J. Chluba; R. A. Sunyaev
Distortion-aware scalable video streaming to multinetwork clients
We consider the problem of scalable video streaming from a server to multinetwork clients over heterogeneous access networks, with the goal of minimizing the distortion of the received videos. This problem has numerous applications including: 1) mobile ... Keywords: quality optimization, rate control, stream adaptation, video streaming
Nikolaos M. Freris, Cheng-Hsin Hsu, Jatinder Pal Singh, Xiaoqing Zhu
Nonequilibrium thermodynamics of a squeezed harmonic oscillator
We consider the thermodynamic properties of the squeezed vacuum state of a frequency--modulated quantum harmonic oscillator. We analytically relate the squeezing parameter to the irreversible work and the degree of nonadiabaticity of the frequency transformation. We furthermore determine the optimal modulation that leads to maximal squeezing, and discuss its implementation as well as the detection of squeezing in single cold ion traps.
Fernando Galve; Eric Lutz
A nonlinear approach to harmonic signal modeling
Periodic signals can be estimated recursively by exploiting the fact that a sine wave passing through a static nonlinear function generates a spectrum of overtones. A real wave with unknown period in cascade with a piecewise linear function is thefefore ... Keywords: Wiener model structure, frequency estimation, harmonic modeling, local convergence, recursive identification
Emad Abd-Elrady
Selective compensation of voltage harmonics in grid-connected microgrids
1 Selective compensation of voltage harmonics in grid-connected microgrids Mehdi Savaghebia , Juan is proposed for selective compensation of main voltage harmonics in a grid- connected microgrid. The aim level. Keywords Distributed Generator (DG); microgrid; grid-connected; voltage harmonics compensation. 1
Vasquez, Juan Carlos
Analysis of inverter models and harmonic propagation. Part II. Harmonic propagation
Part II of a three part study describes the harmonic propagation in the photovoltaic power system consisting of the solar cell array, the inverter, and the ac side of the inverter up to the infinite bus of the utility. Propagation of the harmonics in the utility system are not addressed. Two main problems are analyzed: power in the converter system and harmonics of the current and voltage waveforms of the single-phase, dependent inverter. Relationships between the different components of the converter power - active, reactive and disturbance - are discussed. All formulas necessary for calculating the power components are given, assuming the harmonics of the current and voltage waveforms are known. The theoretical and experimental investigation of the single-phase, dependent inverter is described. The ac and dc terminal voltage of the inverter are analyzed and their harmonics are obtained. These data determine the harmonic propagation on both the dc and ac sides and may be useful for equipment design. Part I of the study (SAND 7040/1) contains a detailed description of the microcomputer based simulator that represents the output characteristics of the five commercially available types of solar cell arrays under different environmental conditions, and Part III (SAND 7040/3) presents an analysis of the transient and steady-state processes of inverter modules.
Slonim, M.A.; Stanek, E.K.
Harmonized Emissions Analysis Tool (HEAT) | Open Energy Information
Harmonized Emissions Analysis Tool (HEAT) Harmonized Emissions Analysis Tool (HEAT) Jump to: navigation, search Tool Summary Name: Harmonized Emissions Analysis Tool (HEAT) Agency/Company /Organization: Local Governments for Sustainability Sector: Energy, Land Topics: Co-benefits assessment, - Health, GHG inventory, Implementation, Pathways analysis Resource Type: Software/modeling tools User Interface: Website Complexity/Ease of Use: Moderate Website: www.environmenttools.co.uk/directory/tool/name/harmonized-emissions-an Cost: Free Harmonized Emissions Analysis Tool (HEAT) Screenshot References: ICLEI-HEAT[1] Related Tools Energy Forecasting Framework and Emissions Consensus Tool (EFFECT) Prospective Outlook on Long-Term Energy Systems (POLES) ICCT Roadmap Model ... further results Find Another Tool
Harmon Electric Assn Inc | Open Energy Information
Harmon Electric Assn Inc Harmon Electric Assn Inc Place Oklahoma Utility Id 8183 Utility Location Yes Ownership C NERC Location SPP NERC SPP Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png 100 Watt HPS Lighting 175 Watt MVL Lighting Co-Generation Rider Commercial Commercial, Single-Phase Commercial Commercial, Three-Phase Commercial Controllable Irrigation, 101HP or more Commercial Controllable Irrigation, 10HP or Less Commercial Controllable Irrigation, 11 to 25 HP Commercial Controllable Irrigation, 26 to 75 HP Commercial Controllable Irrigation, 76 to 100 HP Commercial
Honeycomb optical lattices with harmonic confinement
We consider the fate of the Dirac points in the spectrum of a honeycomb optical lattice in the presence of a harmonic confining potential. By numerically solving the tight binding model, we calculate the density of states and find that the energy dependence can be understood from analytical arguments. In addition, we show that the density of states of the harmonically trapped lattice system can be understood by application of a local density approximation based on the density of states in the homogeneous lattice. The Dirac points are found to survive locally in the trap as evidenced by the local density of states. Furthermore, they give rise to a distinct spatial profile of a noninteracting Fermi gas.
Block, J. Kusk; Nygaard, N. [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark)
Truncated channel representations for coupled harmonic oscillators
Coupled quantum harmonic oscillators, studied by many authors using many different techniques over the decades, are frequently used toy-models to study open quantum systems. In this manuscript, we explicitly study the simplest oscillator model -- a pair of initially decoupled quantum harmonic oscillators interacting with a spring-like coupling, where the bath oscillator is initially in a thermal-like state. In particular, we treat the completely positive and trace preserving map on the system as a quantum channel, and study the truncation of the channel by truncating its Kraus set and its output dimension. We thereby derive the truncated transition amplitudes of the corresponding truncated channel. Finally, we give a computable approximation for these truncated transition amplitudes with explicit error bounds, and perform a case study of the oscillators in the off-resonant and weakly-coupled regime numerically. We demonstrate explicitly that the substantial leakage error can be mitigated via quantum error correction.
Yingkai Ouyang; Wee Hao Ng
Harmon, Illinois: Energy Resources | Open Energy Information
Harmon, Illinois: Energy Resources Harmon, Illinois: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 41.719689°, -89.556564° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.719689,"lon":-89.556564,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Regional Cooperation and Harmonization on EESL
Regional Cooperation and Regional Cooperation and Harmonization on EESL LI Tienan Professor Director of Center for Industrial Energy Efficiency (CIEE) Chairman of ISO/TC 257 Energy Savings 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE) 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE) Roles of EESL Regional EESL Cooperation and Harmonization Focus and Barriers Best Practice: BRESL Project Recommendations Contents 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE) 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE)
Distortion analysis of analog multiplier circuits using two-dimensional integral nonlinear function
This work presents an adaptation to the definition of the Integral Nonlinear Function (INLF) for distortion analysis of analog multipliers. Up to this time distortion in two-input multipliers has been evaluated by applying a constant signal to one of ... Keywords: CMOS multipliers, analog multipliers, distortion
Luciano A. de Lacerda; Edson P. Santana; Cleber Vin�cius A. de Almeida; Ana Isabela A. Cunha
Analysis, design, and experiments of a high-power-factor electronic ballast
A charge pump power-factor-correction (CPPFC) converter is first derived, and its unity power factor condition is then reviewed. A single-stage power-factor-correction electronic ballast using the charge pump concept is analyzed. The design criteria are derived to optimize the electronic ballast based on the steady-state analysis. Constant lamp power operations associated with its control are also discussed. Large signal simulation and experimental results verify the theoretical analysis. It is shown that the designed electronic ballast has 0.995 power factor and 5% total harmonic distortion (THD) with lamp power variation within {+-}15% when the line input voltage changes {+-}10%.
Qian, J.; Lee, F.C. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States); Yamauchi, T. [Matsushita Electric Works, Inc., Woburn, MA (United States)
Electricity Regulation in California and Input Market Distortions
We provide an analysis of the soft price cap regulation that occurred in California�s electricity market between December 2000 and June 2001. We demonstrate the incentive it created to distort the prices of electricity inputs. After introducing a theoretical model of the incentive, we present empirical data from two important input markets: pollution emissions permits and natural gas. We find substantial evidence that generators manipulated these costs in a way that allowed them to justify bids in excess of the price cap and earn higher rents than they could otherwise. Our analysis suggests that the potential benefits of soft price cap regulation were likely undone by such behavior. 1
Mark R. Jacobsen; Azeem M. Shaikh
Separation of High Order Harmonics with Fluoride Windows
The lower orders produced in high order harmonic generation can be effciently temporally separated into monochromatic pulses by propagation in a Fluoride window while still preserving their femtosecond pulse duration. We present calculations for MgF2, CaF2, and LiF windows for the third, fifth, and seventh harmonics of 800 nm. We demonstrate the use of this simple and inexpensive technique in a femtosecond pump/probe experiment using the fifth harmonic.
Allison, Tom; van Tilborg, Jeroen; Wright, Travis; Hertlein, Marcus; Falcone, Roger; Belkacem, Ali
Heat transport in active harmonic chains
We show that a harmonic lattice model with amplifying and attenuating elements, when coupled to two thermal baths, exhibits unique heat transport properties. Some of these novel features include anomalous nonequilibrium steady-state heat currents, negative differential thermal conductance, as well as nonreciprocal heat transport. We find that when these elements are arranged in a PT-symmetric manner, the domain of existence of the nonequilibrium steady state is maximized. We propose an electronic experimental setup based on resistive-inductive-capacitive (RLC) transmission lines, where our predictions can be tested.
Zheng, Mei C.; Ellis, Fred M.; Kottos, Tsampikos; Fleischmann, Ragnar; Geisel, Theo; Prosen, Tomaz [Department of Physics, Wesleyan University, Middletown, Connecticut 06459 (United States); Max-Planck-Institute for Dynamics and Self-organization, Am Fassberg 17, D-37077 Goettingen (Germany) and Institute for Nonlinear Dynamics, Department of Physics, University of Goettingen, D-37077 Goettingen (Germany); Physics Department, Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia)
Harmonizing Global Metrics for Data Center Energy Efficiency...
Harmonizing Global Metrics for Data Center Energy Efficiency The United States of America, European Union and Japan Reach Agreement on Guiding Principles for Data Center Energy...
CERTS 2012 Program Review - IEEE-IEC Harmonization - Ken Martin...
Harmonization Kenneth Martin email@example.com June 12-13, 2012 Washington, DC OE Transmission Reliability Peer Review 1 Introduction Synchrophasor measurement...
Spectral Phase Distribution Retrieval through Coherent Control of Harmonic Generation
The temporal intensity distribution of the third harmonic of a Ti:sapphire laser generated in Xe gas is fully reconstructed from its spectral phase and amplitude distributions. The spectral phases are retrieved by cross correlating the fundamental laser frequency field with that of the third harmonic, in a three laser versus one harmonic photon coupling scheme. The third harmonic spectral amplitude distribution is extracted from its field autocorrelation. The measured pulse duration is found to be in agreement with that expected from lowest order perturbation theory both for unstretched and chirped pulses.
Papalazarou, E.; Charalambidis, D. [Foundation for Research and Technology - Hellas, Institute of Electronic Structure and Laser, PO Box 1527, GR711 10 Heraklion (Crete) (Greece); Department of Physics, University of Crete, PO Box 2208, GR71003 Heraklion (Crete) (Greece); Kovacev, M.; Tzallas, P.; Benis, E.P.; Kalpouzos, C. [Foundation for Research and Technology - Hellas, Institute of Electronic Structure and Laser, PO Box 1527, GR711 10 Heraklion (Crete) (Greece); Tsakiris, G. D. [Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany)
Effects of Power System Harmonics on Distribution Transformer Insulation Performance.
??Floating feeder resonances are one of the new challenges being put forward by the renewable energy based distributed generation (DG) installations. Generally, the harmonic injection� (more)
Hamid, Muhammad
Generation of even harmonics in coupled quantum dots
Using the spatial-temporal symmetry principle we developed recently, we propose an effective scheme for even-harmonics generation in coupled quantum dots. The relative intensity of odd and even harmonic components in the emission spectrum can be controlled by tuning the dipole couplings among the dots, which can be realized in experiments by careful design of the nanostructures. In particular, pure 2nth harmonics and (2n+1)th harmonics (where n is an integer) can be generated simultaneously with polarizations in two mutual perpendicular directions in our systems. An experimental design of the coupled dots system is presented.
Guo Shifang; Duan Suqing; Yang Ning; Chu Weidong; Zhang Wei [Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088 (China)
Harmonizing Global Metrics for Data Center Energy Efficiency, February 2, 2010 Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers...
Energy Savings and Efficiency Improvements through Harmonic Mitigation
harmful harmonics from electrical distribution systems supporting high quantities of computers and other related office equipment. The proliferation of computer and other office...
Solving two-mode squeezed harmonic oscillator and $k$th-order harmonic generation in Bargmann-Hilbert spaces
We analyze the two-mode squeezed harmonic oscillator and the $k$th-order harmonic generation within the framework of Bargmann-Hilbert spaces of entire functions. For the displaced, single-mode squeezed and two-mode squeezed harmonic oscillators, we derive the exact, closed-form expressions for their energies and wave functions. For the $k$th-order harmonic generation with $k\\geq 3$, our result indicates that it does not have eigenfunctions and is thus ill-defined in the Bargmann-Hilbert space.
Yao-Zhong Zhang
Numerical Modeling Study and Assessment of PWR Fuel Rod and Assembly Distortion
Fuel assembly and rod distortion experienced in pressurized water reactors (PWRs) result in numerous operational challenges to plant operators such as mechanical interference between distorted assembly and control rods, difficulties in unloading and reloading cores during outages, and possibly anomalous fuel performance due to atypical water gaps. Therefore, an improved understanding of the various parameters contributing to distortion is important in order to manage or otherwise eliminate these ...
Wind Farm Structures' Impact on Harmonic Emission and Grid Interaction
1 Wind Farm Structures' Impact on Harmonic Emission and Grid Interaction Lukasz Hubert Kocewiak, Jesper Hjerrild, Claus Leth Bak ABSTRACT HE impact of a wind farm's internal structures on harmonic in this paper. The largest wind farms in the world, Horns Rev 2 Offshore Wind Farm and Polish Karnice Onshore
Bak, Claus Leth
Motor voltage high harmonics influence to efficient energy usage
Analysis of the effect of non-sinusoidal voltages on the three-phase induction motor is presented in the paper. When the induction motors are supplied by a rectangular shape of the voltage inverter with high levels of harmonic voltage (Uh,i ... Keywords: energy efficiency, harmonics, induction motor, non-sinusoidal voltage, power losses
Miloje M. Kostic; Branka B. Kostic
ENERGY DIFFUSION IN HARMONIC SYSTEM WITH CONSERVATIVE NOISE GIADA BASILE AND STEFANO OLLA Abstract. We prove diffusive behaviour of the energy fluctua- tions in a system of harmonic oscillators with a stochastic pertur- bation of the dynamics that conserves energy and momentum. The results concern pinned
Cerenkov third-harmonic generation in ,,2... nonlinear photonic crystal
Cerenkov third-harmonic generation in ,,2... nonlinear photonic crystal Yan Sheng,1,a Wenjie Wang,1 of Cerenkov emission of a third-harmonic frequency in a two-dimensional nonlinear photonic crystal, where coherent light called Cerenkov radiation.1 In this process, the mol- ecules of the medium are polarized
Arie, Ady
Higher order harmonic detection for exploring nonlinear interactions
Nonlinear dynamics underpin a vast array of physical phenomena ranging from interfacial motion to jamming transitions. In many cases, decoupling the contributions of competing or co-existing mechanisms to the system response can be achieved through investigation of higher order harmonics. Here, a method using band excitation scanning probe microscopy to investigate higher order harmonics of the electromechanical response, with nanometer scale spatial resolution is presented. The utility of the technique is demonstrated by probing the first three harmonics of strain for a well-known system, a model Pb(Zr1-xTix)O3 ferroelectric capacitor. It is shown that the second order harmonic response is correlated with the first harmonic response, whereas the third harmonic is not. Additionally, nanoscale measurements of the second harmonic response with field reveal significant deviations from Rayleigh-type models in the form of a much more complicated field dependence than is observed in the spatially averaged data. These results illustrate the versatility of combining proximal probe techniques with nth harmonic detection methods in exploring and decoupling nonlinear dynamics in a wide variety of nanoscale materials.
Vasudevan, Rama K [ORNL; Okatan, M. B. [University of New South Wales; Rajapaksa, Indrajit [Oak Ridge National Laboratory (ORNL); Kim, Yunseok [ORNL; Marincel, Dan [Materials Science and Engineering, Pennsylvania State University; Trolier-McKinstry, Susan [Pennsylvania State University; Jesse, Stephen [ORNL; Nagarajan, Valanoor [University of New South Wales; Kalinin, Sergei V [ORNL
Evaluation of the Distortion of a Hydro Turbine Blade during Heat ...
Presentation Title, Evaluation of the Distortion of a Hydro Turbine Blade during Heat Treatment Process. Author(s), Jinwu Kang. On-Site Speaker (Planned)�...
Spectrum of second-harmonic radiation generated from incoherent light
We report on the development of the theory of second-harmonic generation by an incoherent pump with broad angular and frequency spectra. We show that spatial as well as temporal walk-off effects in a nonlinear crystal result in angular dispersion of the second-harmonic radiation. We demonstrate that the acceptance angle in second-harmonic generation by incoherent light is caused by the width of the pump angular spectrum and the resulting angular dispersion of second-harmonic radiation but does not depend on crystal length. In this case the frequency spectrum of second-harmonic radiation is determined by its angular dispersion and the pump angular spectrum. The theory is supported by an experiment in which a LiIO{sub 3} crystal was pumped by a tungsten halogen lamp.
Stabinis, A.; Pyragaite, V.; Tamosauskas, G.; Piskarskas, A. [Department of Quantum Electronics, Vilnius University, Sauletekio Avenue 9, Building 3, LT-10222 Vilnius (Lithuania)
Harmonizing Global Metrics for Data Center Efficiency
Page 1 Page 1 Harmonizing Global Metrics for Data Center Energy Efficiency Global Taskforce Reaches Agreement on Measurement Protocols for PUE - Continues Discussion of Additional Energy Efficiency Metrics February 28th, 2011 The data center has become an increasingly important part of most business operations in the twenty-first century. With escalating demand and rising energy prices, it is essential for the owners and operators of these mission critical facilities to assess and improve their performance with energy efficiency metrics. However, even with the global presence of many companies, these metrics are often not applied consistently at a global level. To address these inconsistencies, a group of global leaders has been meeting regularly to agree
Relativistic high harmonic generation in gas jet targets
We experimentally demonstrate a new regime of high-order harmonic generation by relativistic-irradiance lasers in gas jet targets. Bright harmonics with both odd and even orders, generated by linearly as well as circularly polarized pulses, are emitted in the forward direction, while the base harmonic frequency is downshifted. A 9 TW laser generates harmonics up to 360 eV, within the 'water window' spectral region. With a 120 TW laser producing 40 uJ/sr per harmonic at 120 eV, we demonstrate the photon number scalability. The observed harmonics cannot be explained by previously suggested scenarios. A novel high-order harmonics generation mechanism [T. Zh. Esirkepov et al., AIP Proceedings, this volume], which explains our experimental findings, is based on the phenomena inherent in the relativistic laser - underdense plasma interactions (self-focusing, cavity evacuation, and bow wave generation), mathematical catastrophe theory which explains formation of electron density singularities (cusps), and collective radiation due to nonlinear oscillations of a compact charge.
Pirozhkov, A.S.; Kando, M.; Esirkepov, T.Zh.; and others
Analysis of the electrical harmonic characteristics of a slip recovery variable speed generating system for wind turbine applications
Variable speed electric generating technology can enhance the general use of wind energy in electric utility applications. This enhancement results from two characteristic properties of variable speed wind turbine generators: an improvement in drive train damping characteristics, which results in reduced structural loading on the entire wind turbine system, and an improvement in the overall efficiency by using a more sophisticated electrical generator. Electronic converter systems are the focus of this investigation -- in particular, the properties of a wound-rotor induction generator with the slip recovery system and direct-current link converter. Experience with solid-state converter systems in large wind turbines is extremely limited. This report presents measurements of electrical performances of the slip recovery system and is limited to the terminal characteristics of the system. Variable speed generating systems working effectively in utility applications will require a satisfactory interface between the turbine/generator pair and the utility network. The electrical testing described herein focuses largely on the interface characteristics of the generating system. A MOD-O wind turbine was connected to a very strong system; thus, the voltage distortion was low and the total harmonic distortion in the utility voltage was less than 3% (within the 5% limit required by most utilities). The largest voltage component of a frequency below 60 Hz was 40 dB down from the 60-Hz< component. 8 refs., 14 figs., 8 tabs.
Herrera, J.I.; Reddoch, T.W.
Virtually distortion-free imaging system for large field, high resolution lithography
Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position.
Hawryluk, Andrew M. (Modesto, CA); Ceglio, Natale M. (Livermore, CA)
Computer correction of turbulent distortions of image of extended objects on near-Earth paths
An algorithm of computer-based correction of images of extended objects distorted by turbulent atmosphere is developed. The method of computer correction is used to correct a distorted image of an extended object on a horizontal 2300-m-long observation path. The angular size of the corrected-image region was 15'. (image processing)
Averin, A P; Morozov, Yu B; Pryanichkov, V S; Tyapin, V V [Federal State Unitary Enterprise 'I.S.Kos'minov State Scientific-Research Test Laser Centre of Russian Federation 'Raduga' (Russian Federation)
Vertical displacement of the storage ring floor due to building distortion in the Photon Factory
The Light Source Building of the Photon Factory was found to distort so much as to induce the displacement of magnets in the storage ring. This resulted in drifting of the beam orbit. It was considered that the building was distorted by the variations of thermal stress
Tomotaro Katsura; Yutaka Fujita
Harmonic measurements from a group connected generator HVdc converter scheme
A recent CIGRE document published in ELECTRA has described the potential benefits of a direct connection of generators to HVdc converters. While many theoretical contributions have been made, no practical test data has become available so far. This paper reports on harmonic tests carried out at the Benmore end of the New Zealand HVdc link operating as a group connected scheme. It was found that the measured harmonic current levels were well below specified generator ratings. Dynamic simulation accurately predicted the harmonic currents whereas the results of a steady state formulation were less reliable.
Macdonald, S.J.; Enright, W.; Arrillaga, J. [Univ. of Canterbury, Christchurch (New Zealand); O`Brien, M.T.
Transient beam loading in the ALS harmonic RF system
TRANSIENT BEAM LOADING IN THE ALS HARMONIC RF SYSTEM * J.as the Advanced Light Source (ALS), with moderately low beamharmonic RF system on the ALS storage ring consisting of 5
Harmonics with Fluoride Windows T. K. Allison, 1,2? J. vanpropagation in a ?uoride window while still preserving theirfor MgF 2 , CaF 2 , and LiF windows for the third, ?fth, and
Allison, Tom
Using Coupled Harmonic Oscillators to Model Some Greenhouse Gas Molecules
Common greenhouse gas molecu les SF 6 NO 2 CH 4 and CO 2 are modeled as harmonic oscillators whose potential and kinetic energies are derived. Using the Euler?Lagrange equation
Clark Kendrick C. Go; Joel T. Maquiling
Conversion efficiency, scaling and global optimization of high harmonic generation
Closed form expressions for the high harmonic generation (HHG) conversion efficiency in the plateau and cut-off region are derived showing agreement with previous observations. Application of these results to optimal ...
Falcao-Filho, Edilson L.
Femtosecond second-harmonic generation in periodically poled lithium niobate
Femtosecond second-harmonic generation in periodically poled lithium niobate waveguides poled lithium niobate waveguides under large conversion conditions. Strong saturation of the SHG detailed experi- mental data on femtosecond SHG in periodically poled lithium niobate (PPLN) waveguides
Purdue University
Ontario Harmonization Getting Ready! Issues for University of Western Ontario
first province to harmonize! -British Columbia ·12% HST (July 1, 2010) ·Adopted model similar to Ontario supplied by means of · Wire, pipeline or similar conduit · Satellite or other telecommunications facility
Ma, Bin
Harmonization of Wireless Dimming Lighting Control | Department of Energy
Harmonization of Wireless Dimming Lighting Harmonization of Wireless Dimming Lighting Control Harmonization of Wireless Dimming Lighting Control The U.S. Department of Energy (DOE) is currently conducting research into the harmonization of ZigBee, BACnet-or building automation and control network-and DALI-or digital addressable lighting interface-systems in wireless dimming lighting controls. Four proposed modules will enable "plug-and-play" capabilities for all DALI-compatible controls and BACnet-compatible systems. Project Description This project seeks to develop "plug-and-play" capabilities for lighting as an integrated component of a whole-building control system. Verified Energy, LLC, attempts to demonstrate the benefits of implementing wireless control in dimming applications using plug-and-play principles.
Design and Operation of First-and Second-Harmonic Coaxial Gyroklystrons for Advanced Accelerator Applications
Castle, M; Granatstein, V L; Hogan, B; Lawson, W; Reiser, M; Xu, X
Absorption of ion Bernstein waves by impurity cyclotron harmonics
DOE Green Energy (OSTI)
This paper analyzes the damping of externally-launched ion Bernstein waves by absorption at the cyclotron harmonics of the impurity ions. The inclusion of the non-magnetic energy flux term reduces the damping rate by nearly two orders of magnitude from the previous calculation. Excessive impurity damping can be avoided by launching ion Bernstein waves at a frequency just below the second (or higher) cyclotron harmonic of hydrogen.
Ono, M.
Wind LCA Harmonization (Fact Sheet), NREL (National Renewable Energy Laboratory)
NREL recently led the Life Cycle Assessment (LCA) Harmonization Project, a study that provides more exact estimates of GHG emissions for renewable and conventional generation, clarifying inconsistent and conflicting estimates in the published literature, and reducing uncertainty. This involved a systematic review and harmonization of life cycle assessment (LCA) literature of utility-scale wind power systems in order to determine the causes of life cycle greenhouse gases (GHG) emissions and, where possible, reduce variability in GHG estimates.
Not Available
Debunching into a bucket of lower harmonic number
The adiabatic debunching of beam from buckets of higher harmonic number into waiting buckets of lower harmonic number is a critical step in the current scheme of operation for Tev I. The optimum choice of rf system parameters for this ''bunch coalescing'' process is not immediately obvious. In this note two examples are presented along with generalizations based upon them and experience with the Tevatron I design which can simplify the selection of appropriate parameters for different conditions.
MacLachlan, J.A.; Griffin, J.E.
Power Quality for Transmission and Distribution: Harmonics Design and Analytics Guidebook
The Electric Power Research Institute (EPRI) has published numerous guidebooks, reports, and technical briefs on subjects pertaining to harmonics. Overall, the full EPRI library of documents on harmonics is highly comprehensive and spans the entire range of subject matter, from the effects of harmonic voltages and currents on customer and utility equipment to methodologies useful in conducting harmonic studies. Although this large selection of harmonics-related documents exists, the individual documents ...
Towards unifying multi-resolution and multi-description : a distortion-diversity perspective
We consider codec structures that exploit diversity in both source coding and channel coding components. We propose to study source-channel schemes using the tradeoff between end-to-end distortion level and the outage ...
Jing, Sheng, Ph. D. Massachusetts Institute of Technology
Topographic Distortion of a Cold Front over the Snake River Plain and Central Idaho Mountains
The topographic distortion of a cold front over the Snake River Plain (SRP) and central Idaho Mountains on 3 December 1998 is described using high-density surface observations from MesoWest, a collection of meteorological networks over the ...
W. James Steenburgh; Thomas R. Blazek
Modeling of Electronically Commutated Motor Controlled Fan-powered Terminal Units
Empirical models of airflow and power consumption were developed for series and parallel variable air volume fan powered terminal units (FPTUs). An experimental setup and test procedure were developed to test the terminal units over typical operating ranges. The terminal units in this study used either an 8 in. (20.32 cm) or a 12 in. (30.48 cm) primary air inlet. All terminal units utilized electronically commutated motor (ECM) controllers. Data collected were compared against previous data collected for silicon controlled rectifier (SCR) units. Generalized models were developed for both series and parallel units, and compared against models developed for SCR units. In addition to the performance modeling, power factor and power quality data were also collected for each terminal unit. The power quality analysis included recording and analyzing harmonic distortion for current, voltage, and power up to the 25th harmonic. The total harmonic distortion (THD) was also recorded and presented. For the series terminal units, models were developed for fan airflow, fan power, and primary airflow. The models for fan airflow all had R2 values above 0.987. The models for fan power all had R2 values above 0.968. The models for primary airflow all had R2 values above 0.895. For the parallel terminal units, models were developed for leakage, fan airflow, fan power, and primary airflow. All of the leakage models had R2 values above 0.826. All of the fan airflow models had R2 values above 0.955. All of the fan power models had R2 values above 0.922. All of the primary airflow models had R2 values above 0.872. The real power THD was below 1.5 percent for both series and parallel FPTUs. The current THD ranged from 84 percent to 172 percent for series FPTUs and from 83 percent to 183 percent for parallel FPTUs. The voltage THD was below 1.4 percent for both series and parallel FPTUs. The performance models developed will help improve the accuracy of building energy simulation programs for heating, ventilation, and air conditioning (HVAC) systems utilizing ECM controlled FPTUs. Increasing the accuracy of these simulations will allow HVAC system designers to better optimize their designs for specific building types in a wide variety of climates.
Edmondson, Jacob Lee
Harmonizing Global Metrics for Data Center Energy Efficiency, February 2,
Harmonizing Global Metrics for Data Center Energy Efficiency, Harmonizing Global Metrics for Data Center Energy Efficiency, February 2, 2010 Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In This Section Campaigns Commercial building design Communications resources Energy management guidance Financial resources Portfolio Manager Products and purchasing Recognition Research and reports Service and product provider (SPP) resources
Third-harmonic generation and multiphoton ionization spectroscopy
Nonlinear phenomena, such as multiphoton excitation (MPE) processes leading to ionization and third-harmonic generation (THG) in gases have become the issue of extensive studies over recent years. Studies in rare gases in particular have resulted in several interesting observations in this respect. Thus, it has been established that three-photon resonantly enhanced multiphoton ionization (MPI) in the vicinity of states which are single photon optically coupled to the ground state may occur in efficient competition with THG. The present work demonstrates several new effects which may appear when third-harmonic radiation is present during MPI.
Fotakis, C.; Stockdale, J.A.D.; Proctor, M.J.
Cascaded Cerenkov third-harmonic generation in random quadratic media
We investigate experimentally and theoretically the conical emission of Cerenkov-type third-harmonic generation in strontium barium niobate of random 2D-{chi}{sup (2)} distribution. The azimuthal intensity distribution is explained by the polarization properties of the fundamental and Cerenkov second-harmonic waves, depending on the cascaded origin of the generation process. Moreover, we show the role of the individual domain shape in an additional modulation on the conical emission, controlled by the electrical switching of the spontaneous polarization of the ferroelectric medium.
Ayoub, Mousa; Roedig, Philip; Imbrock, Joerg; Denz, Cornelia [Institute of Applied Physics and Center for Nonlinear Science (CeNoS), Westfaelische Wilhelms-Universitaet Muenster, Corrensstrasse 2, 48149 Muenster (Germany)
Harmonic mean, the Gamma factor and Speed of Light
The relationship between the harmonic mean and special relativity is concisely elucidated. The arguments in favor and against SRT are explored. It is shown that the ratio of the speed of light to the harmonic mean of the onward and return speeds of light in a moving frame under Newtonian mechanics, when equitably distributed between space and time as a correction, leads to the Lorentz transformation. This correction implies an apparent contraction of objects and time dilation. However, the symmetry of the onward and inverse transformations give a different meaning to the gamma factor
Chandru Iyer
Effect of Structural Modification on Second Harmonic Generation in Collagen
The effects of structural perturbation on second harmonic generation in collagen were investigated. Type I collagen fascicles obtained from rat tails were structurally modified by increasing nonenzymatic cross-linking, by thermal denaturation, by collagenase digestion, or by dehydration. Changes in polarization dependence were observed in the dehydrated samples. Surprisingly, no changes in polarization dependence were observed in highly crosslinked samples, despite significant alterations in packing structure. Complete thermal denaturation and collagenase digestion produced samples with no detectable second harmonic signal. Prior to loss of signal, no change in polarization dependence was observed in partially heated or digested collagen.
Stoller, P C; Reiser, K M; Celliers, P M; Rubenchik, A M
Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides
Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print Beyond the Lone-Pair Model for Structurally Distorted Metal Oxides Print "Ferroelectricity," by analogy to ferromagnetism, is defined as the presence of spontaneous electrical polarization in a material, often arising from distortions in the material's crystal structure. In oxides of the metals lead and bismuth, such distortions were for many years attributed to the existence of "lone pair" electrons: pairs of chemically inert, nonbonding valence electrons in hybrid orbitals that leave noticeable voids in the crystal structure. At the ALS, researchers from the U.K., Ireland, and the U.S. have now obtained definitive experimental evidence that this lone-pair model must be revised. High-resolution x-ray photoemission spectroscopy (XPS) and soft x-ray emission spectroscopy (XES) have clarified the subtle electronic origins of the prototypical distortions in these crystal structures. The results have important implications for the tantalizing possibility of spintronic or superconducting devices combining ferroelectric and ferromagnetic properties.
Fault Detection and Diagnostics for Non-Intrusive Monitoring Using Motor Harmonics
Harmonic analysis of motor current has been used to track the speed of motors for sensorless control. Algorithms exist that track the speed of a motor given a dedicated stator current measurement, for example. Harmonic ...
Orji, Uzoma A.
The Spherical Harmonics Discrete Ordinate Method for Three-Dimensional Atmospheric Radiative Transfer
A new algorithm for modeling radiative transfer in inhomogeneous three-dimensional media is described. The spherical harmonics discrete ordinate method uses a spherical harmonic angular representation to reduce memory use and time computing the ...
K. Franklin Evans
Four-Stream Spherical Harmonic Expansion Approximation for Solar Radiative Transfer
This paper presents a four-stream extension of the ?-Eddington approximation by considering the higher-order spherical harmonic expansion in radiative intensity. By using the orthogonality relation of the spherical harmonic functions, the ...
J. Li; V. Ramaswamy
Elimination of Harmonics in a Multilevel Converter for HEV Applications
possible solu- tions are found. Keywords Hybrid Electric Vehicles, Multilevel Convert- ers, Harmonic Elimination, Resultants I. Introduction Designs for heavy duty hybrid-electric vehicles (HEVs) that have large electric drives such as tractor trailers, trans- fer trucks, or military vehicles will require advanced
Tolbert, Leon M.
Controllability of the coupled spin-half harmonic oscillator system
We present a control-theoretic analysis of the system consisting of a two-level atom coupled with a quantum harmonic oscillator. We show that by applying external fields with just two resonant frequencies, any desired unitary operator can be generated.
Haidong Yuan; Seth Lloyd
Harmonic generation of ion waves due to Brillouin backscattering
We report results of simulations of stimulated Brillouin backscatter in which we see the second spatial harmonic of the ion density fluctuation and compare with linear, fluid theory. We also describe examples of the competition between Raman and Brillouin backscatter. 21 refs., 3 figs.
Estabrook, K.; Kruer, W.L.; Haines, M.G.
Web-assisted tunneling in the kicked harmonic oscillator
We show that heating of harmonically trapped ions by periodic delta kicks is dramatically enhanced at isolated values of the Lamb-Dicke parameter. At these values, quasienergy eigenstates localized on island structures undergo avoided crossings with extended web-states.
Andr� R. R. Carvalho; Andreas Buchleitner
Imaging Collagen Orientation Using Polarization-Modulated Second Harmonic Generation
We use polarization-modulated second harmonic generation to image fiber orientation in collagen tissues, with an axial resolution of about 10 {micro}m and a transverse resolution of up to 1 {micro}m. A linearly polarized ultra-short pulse (200 fs) Ti:Sapphire laser beam is modulated using an electro-optic modulator and quarter-wave plate combination and focused onto a translation stage mounted sample using a microscope objective. The generated second harmonic light is collected using a photomultiplier tube and demodulated using phase sensitive detection to obtain signal intensity and fiber orientation information. In order to obtain second harmonic generation images of different types of collagen organization, we analyze several different tissues, including rat-tail tendon, mouse aorta, mouse fibrotic liver, and porcine skin. We can use our technique to image fibrotic tissue in histological sections of damaged liver and to identify burned tissue in porcine skin to a depth of a few hundred microns. Polarization-modulated second harmonic generation potentially could be a useful clinical technique for diagnosing collagen related disease or damage, especially in the skin.
Stoller, P; Celliers, P M; Reiser, K M; Rubenchik, A M
Enhanced Harmonic Up-Conversion Using a Hybrid HGHG-EEHG Scheme
We introduce a novel harmonic generation scheme which can be used, for a given desired harmonic, to achieve higher bunching factors, weaker chicanes, and/or less final energy spread than can be achieved using Echo-Enabled Harmonic Generation. This scheme only requires a single laser with relatively low power, and is a hybrid of High-Gain Harmonic Generation and EEHG. We present a design of this scheme applied to the Next Generation Light Source (NGLS).
Marksteiner, Quinn R. [Los Alamos National Laboratory; Bishofberger, Kip A. [Los Alamos National Laboratory; Carlsten, Bruce E. [Los Alamos National Laboratory; Freund, Henry P. [Los Alamos National Laboratory; Yampolsky, Nikolai A. [Los Alamos National Laboratory
A three-phase converter model for harmonic analysis of HVDC systems
An equivalent circuit model is presented to model bridge converters for three-phase HVDC harmonic power flow analysis. The validity and accuracy of the model are verified by comparing simulation results against field test results. The model is interfaced with a multiphase harmonic load flow program to investigate the generation of non-characteristic harmonics from HVDC links and the flow of HVDC harmonics in a real system.
Xu, W.; Drakos, J.E.; Mansour, Y.; Chang, A. (B.C. Hydro, Burnaby, British Columbia (Canada))
Improvement of the disc harmonic moments descriptor by an exponentially decaying distance transform
The authors propose an improvement of a recent region-based shape descriptor inspired by the 3D spherical harmonics: the Disk Harmonic Moments Descriptor (DHMD). The binary image is weighted by an exponentially decaying distance transform (EDDT) before ... Keywords: content-based image, distance transform, legendre polynomials, region-based shape descriptor, retrieval, salience distance transform, spherical harmonics
Noureddine Ennahnahi; Mohammed Oumsis; Mohammed Meknassi
On Optimum End-to-End Distortion in Wideband MIMO Systems
This paper presents the impact of frequency diversity on the optimum expected end-to-end distortion (EED) in an outage-free wideband multiple-input multiple-output (MIMO) system. We provide the closed-form expression of optimum asymptotic expected EED comprised of the optimum distortion exponent and the multiplicative optimum distortion factor for high signal-to-noise ratio (SNR). It is shown that frequency diversity can improve EED though it has no effect on ergodic capacity. The improvement becomes slight when the frequency diversity order is greater than a certain number. The lower bounds related to infinite frequency diversity are derived. The results for outage-free systems are the bounds for outage-suffering systems and they are instructive for system design.
Chen, Jinhui
Approximate treatment of electron Coulomb distortion in quasielastic (e,e') reactions
In this paper we address the adequacy of various approximate methods of including Coulomb distortion effects in (e,e') reactions by comparing to an exact treatment using Dirac-Coulomb distorted waves. In particular, we examine approximate methods and analyses of (e,e') reactions developed by Traini et al. using a high energy approximation of the distorted waves and phase shifts due to Lenz and Rosenfelder. This approximation has been used in the separation of longitudinal and transverse structure functions in a number of (e,e') experiments including the newly published 208Pb(e,e') data from Saclay. We find that the assumptions used by Traini and others are not valid for typical (e,e') experiments on medium and heavy nuclei, and hence the extracted structure functions based on this formalism are not reliable. We describe an improved approximation which is also based on the high energy approximation of Lenz and Rosenfelder and the analyses of Knoll and compare our results to the Saclay data. At each step of our analyses we compare our approximate results to the exact distorted wave results and can therefore quantify the errors made by our approximations. We find that for light nuclei, we can get an excellent treatment of Coulomb distortion effects on (e,e') reactions just by using a good approximation to the distorted waves, but for medium and heavy nuclei simple additional ad hoc factors need to be included. We describe an explicit procedure for using our approximate analyses to extract so-called longitudinal and transverse structure functions from (e,e') reactions in the quasielastic region.
K. S. Kim; L. E. Wright; Yanhe Jin; D. W. Kosik
Vacuum oscillations of solar neutrinos: correlation between spectrum distortion and seasonal variations
Long length vacuum oscillations solution of the solar neutrino problem is discussed. We show that there is a strict correlation between a distortion of the neutrino energy spectrum and an amplitude of seasonal variations of the neutrino flux. The slope parameter which characterizes a distortion of the recoil electron energy spectrum in the Super-Kamiokande experiment and the seasonal asymmetry of the signal have been calculated in a wide range of oscillation parameters. The correlation of the slope and asymmetry gives crucial criteria for identification or exclusion of this solution. For the positive slope indicated by preliminary Super-Kamiokande data we predict (40 - 60) % enhancement of the seasonal variations.
S. P. Mikheyev; A. Yu. Smirnov
Calculation of HVDC converter noncharacteristic harmonics using digital time-domain simulation method
In this paper, noncharacteristic harmonics of an HVdc converter station are calculated based on the use of digital time-domain simulation methods. An enhanced version of the Electromagnetic Transients Program (EMTP) is used for the studies. The noncharacteristic harmonics of interest are (1) the dc side triplen harmonics, and (2) the ac side second harmonic. Impacts of loading conditions, neutral filter, and converter firing angle on the dc side triplen harmonics are discussed. Effects of ac side network parameters, static VAR compensator (SVC), transformer half-cycle saturation, and Geomagnetically Induced Current (GIC) on the ac side second harmonic instability are also presented. This paper concludes that the digital time-domain simulation method provides significant flexibility for accurate prediction of (1) generation mechanism, and (2) adverse impacts of HVdc noncharacteristic harmonics.
Sarshar, A. [Trench Electric, Scarborough, Ontario (Canada); Iravani, M.R.; Li, J. [Univ. of Toronto, Ontario (Canada). Dept. of Electrical and Computer Engineering
Impact of lattice geometry distortion due to ageing on selected physics parameters of a CANDU reactor
In this paper, results related to a limited scope assessment of the geometry-distortion-induced effects on key reactor physics parameters of a CANDU reactor are discussed. These results were generated by simulations using refined analytical methods and detailed modeling of CANDU reactor core with aged lattice cell geometry. (authors)
Tholammakkil, J. [Canadian Nuclear Safety Commission, P.O. Box 1046, Ottawa, Ont. (Canada); Rahnema, F. [Georgia Inst. of Technology, Atlanta, GA 30332-0405 (United States); Ilas, G. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States); Stamm'ler, R. [Studsvik Scandpower AS, P.O. Box 15, NO-2027 Kjeller (Norway); Khotylev, V.; Serghiuta, D. [Canadian Nuclear Safety Commission, P.O. Box 1046, Ottawa, Ont. (Canada)
A Rate-Energy-Distortion Analysis for Compressed-Sensing-Enabled Wireless Video Streaming on
A Rate-Energy-Distortion Analysis for Compressed-Sensing-Enabled Wireless Video Streaming. The objective of this paper is to conduct an experiment- driven analysis of the energy on Multimedia Sensors Scott Pudlewski, Tommaso Melodia Department of Electrical Engineering State University
Melodia, Tommaso
Region-of-interest video coding based on rate and distortion variations for H.263+
Region-of-interest (ROI) is an essential task that one must undertake in low bit-rate multimedia communications because of the limited bandwidth of the channels and the transcoder between different standards. In this paper, an effective ROI determination ... Keywords: H.263+, Rate control, Rate-distortion, Region-of-interest, Videoconference
Ming-Chieh Chi; Mei-Juan Chen; Chia-Hung Yeh; Jyong-An Jhu
Interference Suppression Consisting of Pre-distortion Filtering and Selective Transmit Diversity
In this paper we present and evaluate a pre-distortion (PD) scheme for the downlink of Wideband-code division multiple access (W-CDMA) systems considering a Rake in the receiver in order to exploit multipath diversity. Its performance is compared with ... Keywords: Downlink transmission, Frequency-selective channels, Pre-processing, Selective transmit diversity, W-CDMA
M�rio Marques Silva; Am�rico M. Correia; Rui Dinis
Using quad smoothness to efficiently control capacity-distortion of reversible data hiding
One of the main uses of data hiding is to protect secret messages being transmitted on the Internet. Reversible data hiding can fully recover the original host image after extracting the secret message. It is especially suitable for applications where, ... Keywords: Capacity-distortion control, Difference expansion, Reversible data hiding, Steganography
Chi-Nan Lin; Daniel J. Buehrer; Chin-Chen Chang; Tzu-Chuen Lu
The Evolution of Distorted Rotating Black Holes I: Methods and Tests
We have developed a new numerical code to study the evolution of distorted, rotating black holes. We discuss the numerical methods and gauge conditions we developed to evolve such spacetimes. The code has been put through a series of tests, and we report on (a) results of comparisons with codes designed to evolve non-rotating holes, (b) evolution of Kerr spacetimes for which analytic properties are known, and (c) the evolution of distorted rotating holes. The code accurately reproduces results of the previous NCSA non-rotating code and passes convergence tests. New features of the evolution of rotating black holes not seen in non-rotating holes are identified. With this code we can evolve rotating black holes up to about $t=100M$, depending on the resolution and angular momentum. We also describe a new family of black hole initial data sets which represent rotating holes with a wide range of distortion parameters, and distorted non-rotating black holes with odd-parity radiation. Finally, we study the limiting slices for a maximally sliced rotating black hole and find good agreement with theoretical predictions.
Steven R. Brandt; Edward Seidel
The detection of multiple mode harmonic kink oscillations in coronal loops enables us to obtain information on coronal density stratification and magnetic field expansion using seismology inversion techniques. The inference is based on the measurement of the period ratio between the fundamental mode and the first overtone and theoretical results for the period ratio under the hypotheses of coronal density stratification and magnetic field expansion of the wave guide. We present a Bayesian analysis of multiple mode harmonic oscillations for the inversion of the density scale height and magnetic flux tube expansion under each of the hypotheses. The two models are then compared using a Bayesian model comparison scheme to assess how plausible each one is given our current state of knowledge.
Arregui, I.; Asensio Ramos, A.; Diaz, A. J., E-mail: firstname.lastname@example.com [Instituto de Astrofisica de Canarias, Via Lactea s/n, E-38205 La Laguna, Tenerife (Spain)
Damping the zero-point energy of a harmonic oscillator
The physics of quantum electromagnetism in an absorbing medium is that of a field of damped harmonic oscillators. Yet until recently the damped harmonic oscillator was not treated with the same kind of formalism used to describe quantum electrodynamics in a arbitrary medium. Here we use the techniques of macroscopic QED, based on the Huttner--Barnett reservoir, to describe the quantum mechanics of a damped oscillator. We calculate the thermal and zero-point energy of the oscillator for a range of damping values from zero to infinity. While both the thermal and zero-point energies decrease with damping, the energy stored in the oscillator at fixed temperature increases with damping, an effect that may be experimentally observable. As the results follow from canonical quantization, the uncertainty principle is valid for all damping levels.
T. G Philbin; S. A. R. Horsley
On the moment of inertia of a quantum harmonic oscillator
An original method for calculating the moment of inertia of the collective rotation of a nucleus on the basis of the cranking model with the harmonic-oscillator Hamiltonian at arbitrary frequencies of rotation and finite temperature is proposed. In the adiabatic limit, an oscillating chemical-potential dependence of the moment of inertia is obtained by means of analytic calculations. The oscillations of the moment of inertia become more pronounced as deformations approach the spherical limit and decrease exponentially with increasing temperature.
Khamzin, A. A., E-mail: firstname.lastname@example.com; Sitdikov, A. S. [Kazan (Volga region) Federal University (Russian Federation)] [Kazan (Volga region) Federal University (Russian Federation); Nikitin, A. S. [Kazan State Power-Engineering University (Russian Federation)] [Kazan State Power-Engineering University (Russian Federation); Roganov, D. A. [Open Corporation Joint-Stock Commercial Investment Bank Tatfondbank (Russian Federation)] [Open Corporation Joint-Stock Commercial Investment Bank Tatfondbank (Russian Federation)
Simulation of Distortion and Residual Stress Development During Heat Treatment of Steel Castings
Heat treatment and associated processing, such as quenching, are critical during high strength steel casting production. These processes must be managed closely to prevent thermal and residual stresses that may result in distortion, cracking (particularly after machining), re-work, and weld repair. The risk of casting distortion limits aggressive quenching that can be beneficial to the process and yield an improved outcome. As a result of these distortions, adjustments must be made to the casting or pattern design, or tie bars must be added. Straightening castings after heat treatments can be both time-consuming and expensive. Residual stresses may reduce a casting�?�?�?¢�?�?�?�?�?�?�?�?s overall service performance, possibly resulting in catastrophic failure. Stress relieving may help, but expends additional energy in the process. Casting software is very limited in predicting distortions during heat treatment, so corrective measures most often involve a tedious trial-and-error procedure. An extensive review of existing heat treatment residual stress and distortion modeling revealed that it is vital to predict the phase transformations and microstructure of the steel along with the thermal stress development during heat treatment. After reviewing the state-of-the-art in heat treatment residual stress and distortion modeling, an existing commercial code was selected because of its advanced capabilities in predicting phase transformations, the evolving microstructure and related properties along with thermal stress development during heat treatment. However, this software was developed for small parts created from forgings or machined stock, and not for steel castings. Therefore, its predictive capabilities for heat treatment of steel castings were investigated. Available experimental steel casting heat treatment data was determined to be of insufficient detail and breadth, and so new heat treatment experiments were designed and performed, casting and heat treating modified versions of the Navy-C ring (a classical test shape for heat treatment experiments) for several carbon and low alloy steels in order to generate data necessary to validate the code. The predicted distortions were in reasonable agreement with the experimentally measured values. However, the final distortions in the castings were small, making it difficult to determine how accurate the predictions truly are. It is recommended that further validation of the software be performed with the aid of additional experiments with large production steel castings that experience significant heat treatment distortions. It is apparent from this research that the mechanical properties of the bonded sand used for cores and sand molds are key in producing accurate stress simulation results. Because of this, experiments were performed to determine the temperature-dependent elastic modulus of a resin-bonded sand commonly utilized in the steel casting industry. The elastic modulus was seen to vary significantly with heating and cooling rates. Also, the retained room temperature elastic modulus after heating was seen to degrade significantly when the sand was heated above 125�?�?�?�?�?�?�?°C. The elastic modulus curves developed in this work can readily be utilized in casting simulation software. Additional experiments with higher heating rates are recommended to determine the behavior of the elastic modulus in the sand close to the mold-metal interface. The commercial heat treatment residual stress and distortion code, once fully validated, is expected to result in an estimated energy savings of 2.15 trillion BTU�?�?�?¢�?�?�?�?�?�?�?�?s/year. Along with these energy savings, reduction of scrap and improvement in casting yield will result in a reduction of the environmental emissions associated with the melting and pouring of the metal which will be saved as a result of this technology.
Christoph Beckermann; Kent Carlson
Dynamics of Flat Bunches with Second Harmonic RF
We investigate the dynamics of longitudinally flat bunches created with a second harmonic cavity in a high energy collider. We study Landau damping in a second harmonic cavity with analytical and numerical methods. The latter include particle tracking and evolution of the phase space density. The results are interpreted in the context of possible application to the LHC. A possible path to a luminosity upgrade at the LHC is through the creation of longitudinally flat bunches. They can increase the luminosity roughly by 40% when the beam intensities are at the beam-beam limit. Lower momentum spread which can reduce backgrounds and make collimation easier as well lower peak fields which can mitigate electron cloud effects are other advantages. Use of a second harmonic rf system is a frequently studied method to create such flat bunches. Here we consider some aspects of longitudinal dynamics of these bunches in the LHC at top energy. First we consider intensity limits set by the loss of Landau damping against rigid dipole oscillations. Next we describe numerical simulations using both particle tracking and evolution of the phase space density. These simulations address the consequences of driving a bunch at a frequency that corresponds to the maximum of the synchrotron frequency.
Sen, Tanaji; /Fermilab; Bhat, Chandra; /Fermilab; Kim, Hyung Jin; /Fermilab; Ostiguy, Jean-Francois; /Fermilab
Background and Reflections on the Life Cycle Assessment Harmonization Project
Despite the ever-growing body of life cycle assessment (LCA) literature on electricity generation technologies, inconsistent methods and assumptions hamper comparison across studies and pooling of published results. Synthesis of the body of previous research is necessary to generate robust results to assess and compare environmental performance of different energy technologies for the benefit of policy makers, managers, investors, and citizens. With funding from the U.S. Department of Energy, the National Renewable Energy Laboratory initiated the LCA Harmonization Project in an effort to rigorously leverage the numerous individual studies to develop collective insights. The goals of this project were to: (1) understand the range of published results of LCAs of electricity generation technologies, (2) reduce the variability in published results that stem from inconsistent methods and assumptions, and (3) clarify the central tendency of published estimates to make the collective results of LCAs available to decision makers in the near term. The LCA Harmonization Project's initial focus was evaluating life cycle greenhouse gas (GHG) emissions from electricity generation technologies. Six articles from this first phase of the project are presented in a special supplemental issue of the Journal of Industrial Ecology on Meta-Analysis of LCA: coal (Whitaker et al. 2012), concentrating solar power (Burkhardt et al. 2012), crystalline silicon photovoltaics (PVs) (Hsu et al. 2012), thin-film PVs (Kim et al. 2012), nuclear (Warner and Heath 2012), and wind (Dolan and Heath 2012). Harmonization is a meta-analytical approach that addresses inconsistency in methods and assumptions of previously published life cycle impact estimates. It has been applied in a rigorous manner to estimates of life cycle GHG emissions from many categories of electricity generation technologies in articles that appear in this special supplemental supplemental issue, reducing the variability and clarifying the central tendency of those estimates in ways useful for decision makers and analysts. Each article took a slightly different approach, demonstrating the flexibility of the harmonization approach. Each article also discusses limitations of the current research, and the state of knowledge and of harmonization, pointing toward a path of extending and improving the meta-analysis of LCAs.
Heath, G. A.; Mann, M. K.
Distortions of Experimental Muon Arrival Time Distributions of Extensive Air Showers by the Observation Conditions
Event-by-event measured arrival time distributions of Extensive Air Shower (EAS) muons are affected and distorted by various interrelated effects which originate from the time resolution of the timing detectors, from fluctuations of the reference time and the number (multiplicity) of detected muons spanning the arrival time distribution of the individual EAS events. The origin of these effects is discussed, and different correction procedures, which involve detailed simulations, are proposed and illustrated. The discussed distortions are relevant for relatively small observation distances (R < 200 m) from the EAS core. Their significance decreases with increasing observation distance and increasing primary energies. Local arrival time distributions which refer to the observed arrival time of the first local muon prove to be less sensitive to the mass of the primary. This feature points to the necessity of arrival time measurements with additional information on the curvature of the EAS disk.
R. Haeusler; A. F. Badea; H. Rebel; I. M. Brancus; J. Oehlschlaeger
Coulomb Distortion Effects for (e,e'p) Reactions at High Electron Energy
We report a significant improvement of an approximate method of including electron Coulomb distortion in electron induced reactions at momentum transfers greater than the inverse of the size of the target nucleus. In particular, we have found a new parametrization for the elastic electron scattering phase shifts that works well at all electron energies greater than 300 $MeV$. As an illustration, we apply the improved approximation to the $(e,e'p)$ reaction from medium and heavy nuclei. We use a relativistic ``single particle'' model for $(e,e'p)$ as as applied to $^{208}Pb(e,e'p)$ and to recently measured data at CEBAF on $^{16}O(e,e'p)$ to investigate Coulomb distortion effects while examining the physics of the reaction.
Power Quality and Harmonic Impacts of Distributed Generation Technologies
The PQ TechWatch report series builds on EPRI's broad expertise and power quality testing and evaluation work to provide a vital flow of data, including important information on emerging trends powering ebusinesses and developments in next-generation power quality mitigation and energy storage technologies.This PQ TechWatch aims to present an overview of power quality impacts resulting from operation of DG technologies on the grid. An emphasis on harmonic effects is included here. Concerns in this area a...
Mapping the nonlinear optical susceptibility by noncollinear second harmonic generation
We present a method, based on noncollinear second harmonic generation, to evaluate the non-zero elements of the nonlinear optical susceptibility. At a fixed incidence angle, the generated signal is investigated by varying the polarization state of both fundamental beams. The resulting polarization charts allows to verify if Kleinman symmetry rules can be applied to a given material or to retrieve the absolute value of the nonlinear optical tensor terms, from a reference measurement. Experimental measurements obtained from Gallium Nitride layers are reported. The proposed method does not require an angular scan thus is useful when the generated signal is strongly affected by sample rotation
Larciprete, M C; Giardina, M; Belardini, A; Centini, M; Sibilia, 1 C; Bertolotti, M; Passaseo, A; Tasco, V
A non-conforming 3D spherical harmonic transport solver
A new 3D transport solver for the time-independent Boltzmann transport equation has been developed. This solver is based on the second-order even-parity form of the transport equation. The angular discretization is performed through the expansion of the angular neutron flux in spherical harmonics (PN method). The novelty of this solver is the use of non-conforming finite elements for the spatial discretization. Such elements lead to a discontinuous flux approximation. This interface continuity requirement relaxation property is shared with mixed-dual formulations such as the ones based on Raviart-Thomas finite elements. Encouraging numerical results are presented. (authors)
Van Criekingen, S. [Commissariat a l'Energie Atomique CEA-Saclay, DEN/DM2S/SERMA/LENR Bat 470, 91191 Gif-sur-Yvette, Cedex (France)
Harmonizing Melodies in Real-Time: the Connectionist Approach
We describe a sequential neural network for harmonizing melodies in real time. It models aspects of human cognition. This neural network succeeds reasonably well, if we take into consideration the constraints imposed by real time processing. The model exploits efficiently the available sequential information. The net contains a sub-net for meter that produces a periodic index of meter, providing the needed metric awareness. The net learns the relations between important notes of the melody and their harmonies and is able to produce harmonies for new melodies in real time, i.e., without knowledge of the future development of the melody.
Dan Gang; Daniel Lehmann; Naftali Wagner
Harmonic coordinates in the string and membrane equations
In this note, we first show that the solutions to Cauchy problems for two versions of relativistic string and membrane equations are diffeomorphic. Then we investigate the coordinates transformation presented in D. X. Kong and Q. Zhang [Physica D 238, 902 (2009); see (2.20)] which plays an important role in the study on the dynamics of the motion of string in Minkowski space. This kind of transformed coordinates is harmonic coordinates, and the nonlinear relativistic string equations can be straightforwardly simplified into linear wave equations under this transformation.
He Chunlei; Huang Shoujun [Department of Mathematics, Anhui Normal University, Wuhu 241000 (China)
Non-Markovian quantum Brownian motion of a harmonic oscillator
We apply the density-matrix method to the study of quantum Brownian motion of a harmonic oscillator coupled to a heat bath, a system investigated previously by Caldeira and Leggett using a different method. Unlike the earlier work, in our derivation of the master equation the non-Markovian terms are maintained. Although the same model of interaction is used, discrepancy is found between their results and our equation in the Markovian limit. We also point out that the particular interaction model used by both works cannot lead to the phenomenological generalized Langevin theory of Kubo.
Tang, J.
Coulomb Distortion Effects for Electron or Positron Induced $(e,e')$ Reactions in the Quasielastic Region
In response to recent experimental studies we investigate Coulomb distortion effects on $(e,e')$ reactions from medium and heavy nuclei for the case of electrons and positrons. We extend our previously reported full DWBA treatment of Coulomb distortions to the case of positrons for the $^{208}Pb(e,e')$ reaction in the quasielastic region for a particular nuclear model. In addition, we use previously reported successful approaches to treating Coulomb corrections in an approximate way to calculate the Coulomb distortion effects for $(e,e')$ reactions for both electrons and positrons for the case of a simple nuclear model for quasielastic knock-out of nucleons. With these results in hand we develop a simple {\\em ad-hoc} approximation for use in analyzing experiments, and discuss methods of extracting the ``longitudinal structure function" which enters into evaluation of the Coulomb sum rule. These techniques are generally valid for lepton induced reactions on nuclei with momentum transfers greater than approximately 300 $MeV/c$.
K. S. Kim; L. E. Wright; D. A. Resler
Technical Study Addresses a Key Challenge to Harmonizing U.S...
and U.S. and international standards appear to be closer to harmonization. Technical Contacts: John Wohlgemuth, firstname.lastname@example.com; Michael Kempe,...
Numerical studies of third-harmonic generation in laser filament in air perturbed by plasma spot
Third-harmonic emission from laser filament intercepted by plasma spot is studied by numerical simulations. Significant enhancement of the third-harmonic generation is obtained due to the disturbance of the additional plasma. The contribution of the pure plasma effect and the possible plasma-enhanced third-order susceptibility on the third-harmonic generation enhancement are compared. It is shown that the plasma induced cancellation of destructive interference [Y. Liu et al., Opt. Commun. 284, 4706 (2011)] of two-colored filament is the dominant mechanism of the enhancement of third-harmonic generation.
Feng Liubin [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing 100190 (China); Institute of Atomic and Molecular Physics and Department of Physics, Sichuan University, Chengdu 610065 (China); Lu Xin; Liu Xiaolong; Li Yutong; Chen Liming; Ma Jinglong; Dong Quanli; Wang Weimin [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing 100190 (China); Xi Tingting [College of Physical Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Sheng Zhengming; Zhang Jie [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Science, Beijing 100190 (China); Key Laboratory for Laser Plasmas of the Ministry of Education of China and Department of Physics, Shanghai Jiao Tong University, Shanghai 200240 (China); He Duanwei [Institute of Atomic and Molecular Physics and Department of Physics, Sichuan University, Chengdu 610065 (China)
Energy Efficiency Standards and Labels in North America: Opportunities for Harmonization
for harmonization are standby losses, uniform endorsementthe three countries. a) Standby losses: Relevant activities:order on energy efficient standby power devices. The order
Wiel, Stephen
Cholesterol and Phytosterol Oxidation ProductsChapter 6 Harmonization of Cholesterol Oxidation Product Analysis
Cholesterol and Phytosterol Oxidation Products Chapter 6 Harmonization of Cholesterol Oxidation Product Analysis Food Science Health Nutrition Biochemistry eChapters Food Science & Technology Health - Nutrition - Biochemistry Press
Unbalance and Harmonic Concerns When Forging Facility Fed From Backup Generator
This power quality (PQ) case study presents the analysis and mitigation suggestions for unbalance and harmonic concerns when forging a facility fed from a backup generator.
Current-source charge-pump power-factor-correction electronic ballast
A current-source charge-pump power-factor-correction (CS-CPPFC) electronic ballast is presented in this paper. Unity-power-factor condition and principle of operation using the CP concept are derived and analyzed. Based on the steady-state analysis, the design considerations are discussed in detail. It is shown that the power switch only deals with the resonant load current, which is the same as in the two-stage approach so that small-current rating devices can be used. The developed CS-CPPFC electronic ballast can save one inductor and has a potentially low cost. The CS-CP electronic ballast with switching frequency modulation to improve crest factor is developed, implemented, and tested. It is shown that 0.99 power factor, 11.3% total harmonic distortion (THD), and 1.54 crest factor can be achieved for 85-W fluorescent lamps.
Qian, J.; Lee, F.C.Y. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States); Yamauchi, Tokushi [Matsushita Electric Works, Inc., Woburn, MA (United States)
Design and analysis of a scanning beam interference lithography system for patterning gratings with nanometer-level distortions
This thesis describes the design and analysis of a system for patterning large-area gratings with nanometer level phase distortions. The novel patterning method, termed scanning beam interference lithography (SBIL), uses ...
Konkola, Paul Thomas, 1973-
High-order harmonic generation in Xe, Kr, and Ar driven by a 2.1-?m source: High-order harmonic spectroscopy under macroscopic effects
We experimentally and numerically study the atomic response and pulse propagation effects of high-order harmonics generated in Xe, Kr, and Ar driven by a 2.1-?m infrared femtosecond light source. The light source is an ...
Hong, Kyung-Han
Virtually distortion-free imaging system for large field, high resolution lithography using electrons, ions or other particle beams
Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position. Particle beams, including electrons, ions and neutral particles, may be used as well as electromagnetic radiation.
Hawryluk, A.M.; Ceglio, N.M.
Network-Adaptive Video Communication Using Packet Path Diversity and Rate-Distortion Optimized Reference Picture Selection
In this paper, we present error-resilient Internet video transmission using path diversity and rate-distortion optimized reference picture selection. Under this scheme, the optimal packet dependency is determined adapting to network characteristics and ... Keywords: Path diversity, error-resilient video coding, low-latency, network-adaptive video coding, rate-distortion optimization, reference picture selection, source-channel coding, video streaming
Yi J. Liang; Eric Setton; Bernd Girod
Original article: Selective compensation of voltage harmonics in grid-connected microgrids
In this paper, a novel approach is proposed for selective compensation of main voltage harmonics in a grid-connected microgrid. The aim of compensation is to provide a high voltage quality at the point of common coupling (PCC). PCC voltage quality is ... Keywords: Distributed generator (DG), Grid-connected, Microgrid, Voltage harmonics compensation
Mehdi Savaghebi, Juan C. Vasquez, Alireza Jalilian, Josep M. Guerrero, Tzung-Lin Lee
Computationally fast harmonic balance methods for unsteady aerodynamic predictions of helicopter rotors
A harmonic balance technique for the analysis of unsteady flows about helicopter rotors in forward flight and hover is presented in this paper. The aerodynamics of forward flight are highly nonlinear, with transonic flow on the advancing blade, subsonic ... Keywords: Computational fluid dynamics, Frequency-domain methods, Harmonic balance technique, Helicopter rotors, Unsteady aerodynamics
Kivanc Ekici; Kenneth C. Hall; Earl H. Dowell
Harmonic filters influences regarding the power quality on high frequency electrothermal installation with electromagnetic induction
This paper presents a study regarding the functioning of a melting/hardening electrothermal installation with electromagnetic induction from the point of view of generated harmonics in the power distribution. The authors made simulations in scope of ... Keywords: electrothermal installation, harmonic, passive filters, static converter
Raluca Rob; Ioan Sora; Caius Panoiu; Manuela Panoiu
Harmonic Amplitudes Calculation Method and Simulation of Diode-bridge Rectifier's Output Current
Taking the three-phase uncontrolled diode-bridge rectifier of a certain style armored vehicle�s power supple system as research object, a practical method to calculate the harmonic amplitudes of rectifier�s DC-side output current is theoretically ... Keywords: rectifier, harmonic amplitude, switching function, simulation, MATLAB
Wei Wei; Xiaojun Ma; Shuguang Wei; Zhaozhao He
Study on the Harmonics of Photovoltaic Generation SPWM Inverting Power Supplies
Harmonics are the main polluting source of affecting the power energy quality. In this paper, the causes that SPWM inverter power supply produces the harmonics are analyzed firstly and then a new three-phase ?-band-pass filter is designed to improve ... Keywords: harmonious, solar energy photovoltaic power, inverter, current ripples component
Jianqu Zhu; Feng Wang; Taiqiang Cao
Adjustable Speed Drive: Harmonic Effects on Induction Motors: Volumes 1 and 2
The use of adjustable speed drives (ASDs) for induction motors in electric power plants has several advantages, but ASDs produce harmonic current and voltage that can result in problems. The Standstill Frequency Response (RFR) program for the personal PC can be used to study these harmonic effects in a wide range of motors.
Modeling and experimental validation of internal faults in salient pole synchronous machines including space harmonics
Considering the space harmonics caused by the faulted windings, a simulation model of internal faults in salient pole synchronous machines is proposed in this paper. The model is based on the winding function approach, which makes no assumption for sinusoidal ... Keywords: Internal faults, Space harmonics, Synchronous machines, Winding function
X. Tu; L. -A. Dessaint; M. El Kahel; A. Barry
Multiple Cerenkov second-harmonic waves in a two-dimensional
Multiple Cerenkov second-harmonic waves in a two-dimensional nonlinear photonic structure Wenjie fundamental beams. We show that this phenomenon is caused by the nonlinear Cerenkov radiation emitted due verify the effects of reciprocal vectors on the Cerenkov-type second-harmonic generation in nonlinear
Harmonic generation and wave mixing in nonlinear metamaterials and photonic crystals (Invited paper)
The basic concepts and phenomenology of wave mixing and harmonic generation are reviewed in context of the recent advances in the enhanced nonlinear activity in metamaterials and photonic crystals. The effects of dispersion, field confinement and phase ... Keywords: bandgap, dispersion, harmonic generation, nonlinear metamaterial, pulses
O. Shramkova; A. Schuchinsky
Extraction of voltage harmonics using multi-layer perceptron neural network
This paper presents a harmonic extraction algorithm using artificial neural networks for Dynamic Voltage Restorers (DVRs). The suggested algorithm employs a feed forward Multi Layer Perceptron (MLP) Neural Network with error back propagation learning ... Keywords: Dynamic Voltage Restorer, Harmonic extraction, Multi Layer Perceptron, Neural Networks
Mehmet T�may; M. Emin Meral; K. �a?atay Bayindir
Modeling DFIG Using General Vector Representation in the Presence of Harmonics
In this paper, a doubly-fed induction generator (DFIG) wind turbine is modeled by using the general vector representation of voltage, current and magnetic flux in the presence of harmonics. The general vector representation provides insights into how ... Keywords: wind turbine, harmonics, general vector form, DFIG
Ziqiao Liu, Ahmed Abu-Hajar, David Wenzhong Gao
Image-based spectral distortion correction for photon-counting x-ray detectors
Purpose: To investigate the feasibility of using an image-based method to correct for distortions induced by various artifacts in the x-ray spectrum recorded with photon-counting detectors for their application in breast computed tomography (CT). Methods: The polyenergetic incident spectrum was simulated with the tungsten anode spectral model using the interpolating polynomials (TASMIP) code and carefully calibrated to match the x-ray tube in this study. Experiments were performed on a Cadmium-Zinc-Telluride (CZT) photon-counting detector with five energy thresholds. Energy bins were adjusted to evenly distribute the recorded counts above the noise floor. BR12 phantoms of various thicknesses were used for calibration. A nonlinear function was selected to fit the count correlation between the simulated and the measured spectra in the calibration process. To evaluate the proposed spectral distortion correction method, an empirical fitting derived from the calibration process was applied on the raw images recorded for polymethyl methacrylate (PMMA) phantoms of 8.7, 48.8, and 100.0 mm. Both the corrected counts and the effective attenuation coefficient were compared to the simulated values for each of the five energy bins. The feasibility of applying the proposed method to quantitative material decomposition was tested using a dual-energy imaging technique with a three-material phantom that consisted of water, lipid, and protein. The performance of the spectral distortion correction method was quantified using the relative root-mean-square (RMS) error with respect to the expected values from simulations or areal analysis of the decomposition phantom. Results: The implementation of the proposed method reduced the relative RMS error of the output counts in the five energy bins with respect to the simulated incident counts from 23.0%, 33.0%, and 54.0% to 1.2%, 1.8%, and 7.7% for 8.7, 48.8, and 100.0 mm PMMA phantoms, respectively. The accuracy of the effective attenuation coefficient of PMMA estimate was also improved with the proposed spectral distortion correction. Finally, the relative RMS error of water, lipid, and protein decompositions in dual-energy imaging was significantly reduced from 53.4% to 6.8% after correction was applied. Conclusions: The study demonstrated that dramatic distortions in the recorded raw image yielded from a photon-counting detector could be expected, which presents great challenges for applying the quantitative material decomposition method in spectral CT. The proposed semi-empirical correction method can effectively reduce these errors caused by various artifacts, including pulse pileup and charge sharing effects. Furthermore, rather than detector-specific simulation packages, the method requires a relatively simple calibration process and knowledge about the incident spectrum. Therefore, it may be used as a generalized procedure for the spectral distortion correction of different photon-counting detectors in clinical breast CT systems.
Ding Huanjun; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)
Polarized protons have been stored and accelerated in RHIC from G{sub {gamma}} = 46.5 to 60 during Run2000 with only one Siberian snake installed. We simulated with the spin tracking code Spink the behavior of polarized protons, in particular the effect of closed orbit distortions and betatron tune variation on the spin dynamics. According to simulation results, closed orbit and tune effects will be translated into requirements for the tune and orbit correction systems for the RHIC polarized proton Run2001, when both Siberian snakes will be available.
Measurement and modeling of mirror distortion in a high power FEL
Mirror heating in a high power FEL can alter the optical mode and affect the gain of the laser. This can lead to a large reduction of the laser power from ideal values. Measurements of the power and mode size in the Jefferson Lab IR Demo laser have shown clear evidence of mirror distortion at high average power leading (up to 17 kW incident on the mirrors and over 40 W absorbed per mirror). The measurements and comparisons with modeling will be presented. Both steady state and transient analyses and measurements are considered.
Benson, S.; Neil, G.; Michelle D. Shinn
Intense multimicrojoule high-order harmonics generated from neutral atoms of In{sub 2}O{sub 3} nanoparticles
We studied high-order harmonic generation from plasma that contains an abundance of indium oxide nanoparticles. We found that harmonics from nanoparticle-containing plasma are considerably more intense than from plasma produced on the In{sub 2}O{sub 3} bulk target, with high-order harmonic energy ranging from 6 {mu}J (for the ninth harmonic) to 1 {mu}J (for the 17th harmonic) in the former case. The harmonic cutoff from nanoparticles was at the 21st order, which is lower than that observed using indium oxide solid target. By comparing the harmonic spectra obtained from solid and nanoparticle indium oxide targets, we concluded that intense harmonics in the latter case are dominantly generated from neutral atoms of the In{sub 2}O{sub 3} nanoparticles.
Elouga Bom, L. B.; Abdul-Hadi, J.; Vidal, F.; Ozaki, T. [Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Lionel-Boulet, Varennes, Quebec J3X 1S2 (Canada); Ganeev, R. A. [Centre Energie, Materiaux et Telecommunications, Institut National de la Recherche Scientifique, 1650 Lionel-Boulet, Varennes, Quebec J3X 1S2 (Canada); Scientific Association Akadempribor, Uzbekistan Academy of Sciences, Akademgorodok, Tashkent 100125 (Uzbekistan)
Harmonization of Road Signs for Electric Vehicle Charging Stations
Alternative Fuels and Advanced Vehicles Data Center (EERE)
Avenue Louise 200 Box 113 1050 Brussels Belgium 1 Avenue Louise 200 Box 113 1050 Brussels Belgium 1 32.2.647.3218 Mobile 32.473.284.603 email@example.com www.cleanfuelsconsulting.org Harmonization of Road Signs for Electric Vehicle Charging Stations Prepared for: Argonne National Laboratory and the U.S. Department of Energy November 2012 Avenue Louise 200 Box 113 1050 Brussels Belgium 2 32.2.647.3218 Mobile 32.473.284.603 email@example.com www.cleanfuelsconsulting.org This page is intentionally blank. Avenue Louise 200 Box 113 1050 Brussels Belgium 3 32.2.647.3218 Mobile 32.473.284.603 email@example.com www.cleanfuelsconsulting.org TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................................................. 5
Cherenkov high-order harmonic generation by multistep cascading in {chi}{sup (2)} nonlinear photonic crystal
We propose a scheme for efficient Cherenkov high-order harmonic generation. Second to fifth order harmonic wave are observed in a single periodically poled ferroelectric crystal in our experiment. The noncollinear high-order harmonic generation is produced via enhanced Cherenkov second harmonic cascaded with successive multistep sum-frequency generation with simultaneously longitudinal phase-matching. The emission angle and power dependencies are analyzed in detail experimentally, which coincide with theoretical predictions.
An Ning; Ren Huaijin [Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems, Shanghai 200240 (China); Zheng Yuanlin [Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Key Laboratory for Laser Plasmas (Ministry of Education), Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Deng Xuewei [Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Chen Xianfeng [Department of Physics, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems, Shanghai 200240 (China); Key Laboratory for Laser Plasmas (Ministry of Education), Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)
Standard test method for measurement of roll wave optical distortion in heat-treated flat glass
1.1 This test method is applicable to the determination of the peak-to-valley depth and peak-to-peak distances of the out-of-plane deformation referred to as roll wave which occurs in flat, heat-treated architectural glass substrates processed in a heat processing continuous or oscillating conveyance oven. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This test method does not address other flatness issues like edge kink, ream, pocket distortion, bow, or other distortions outside of roll wave as defined in this test method. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
American Society for Testing and Materials. Philadelphia
Theoretical studies of high-order harmonic generation: Effects of symmetry, degeneracy, and orientation
Using a quantum-mechanical three-step model, we present numerical calculations of the high-order harmonic generation from four polyatomic molecules. Ethylene (C{sub 2}H{sub 4}) serves as an example where orbital symmetry directly affects the harmonic yield. We treat the case of methane (CH{sub 4}) to address the high-order harmonic generation resulting from a molecule with degenerate orbitals. To this end we illustrate how the single-orbital contributions show up in the total high-order harmonic signal. This example illustrates the importance of adding coherently the amplitude contributions from the individual degenerate orbitals. Finally, we study the high-order harmonic generation from propane (C{sub 3}H{sub 8}) and butane (C{sub 4}H{sub 10}). These two molecules, being extended and far from spherical in structure, produce harmonics with nontrivial orientational dependencies. In particular, propane can be oriented so that very high-frequency harmonics are favored, and thus the molecule contains prospects for the generation of uv attosecond pulses.
Madsen, C. B.; Madsen, L. B. [Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, University of Aarhus, 8000 Aarhus C (Denmark)
The Efficacy of Profile Matching as a Means of Controlling for the Effects of Response Distortion on Personality Measures
Researchers and practitioners continue to be concerned about the magnitude, extent, and effects of response distortion when self-report personality measures are used in high-stakes testing. One method for mitigating response distortion that has not received much empirical attention is profile matching. Profile matching assesses the fit between test-takers� predictor profiles and a standard profile which represents an ideal or high performing employee�s profile. Since profile matching assesses fit, it can capture nonlinear effects. Furthermore, high predictor scores are not necessarily associated with higher criterion scores. Test�takers who distort their responses by choosing inaccurately extreme response options may improve their chances of being hired if a linear model is used, but this approach is unlikely to be effective if a profile matching strategy is used as long as the standard profile is unknown to the test-takers. As such, the primary objective of the present study was to examine the extent to which profile matching may alleviate concerns about response distortion. A secondary objective was to examine characteristics of the standard profile that are associated with the efficacy of this approach. The present study compared the effects of response distortion on personality test scores, and their criterion-related validity in predicting tenure, based on a linear composite and a profile fit score. The present study used data from 996 applicants who completed a personality test in a high-stakes testing context. Missing data were imputed for a subset of applicants who did not complete two response distortion scales. As such, the results provided an initial proof-of-concept of the effectiveness of profile matching as a personnel decision-making strategy using a blend of real and simulated data. The results suggest that profile fit scores are less related to response distortion and display higher criterion-related validity than linear composite scores. However, the difference in criterion-related validity could not be attributed to response distortion. The results further suggest that the amount of scatter in the standard profile is negatively associated with the profile fit score�s susceptibility to response distortion and positively related to criterion-related validity.
Glaze, Ryan 1983-
Lack of a Jahn-Teller Distortion in La1-xSrxCoO3 Determined by EXAFS and
Lack of a Jahn-Teller Distortion in Lack of a Jahn-Teller Distortion in La1-xSrxCoO3 Determined by EXAFS and Neutron PDF Studies The transition metal oxides exhibit a wide range of interesting properties, of which superconductivity in the copper oxides and colossal magnetoresistance in the manganese oxides are perhaps the best known. However, the strange magnetic behavior of several cobalt oxides is another example of these unusual properties, although not yet as intensively studied. The cobaltite system La1-xSrxCoO3 (LSCO) has a rich temperature-concentration phase diagram with anti-ferromagnetism and insulating behavior at low Sr concentrations, and ferromagnetism and metallic behavior at higher concentrations. The magnetism for the end compound LaCoO3 (LCO) is particularly unusual; it has no Co spin magnetic moment at low T (and is diamagnetic). As T increases from 4K, the magnetic susceptibility increases dramatically up to roughly 100K, and then decreases as T is increased to 300K. This behavior has been attributed to Co+3 having several different spin configurations. Initially only two were considered, a low spin state (LS, S=0) that is not magnetic and a high spin state (HS, S=2) that is strongly magnetic. In the '90s a third, intermediate spin configuration (IS, S=1) was proposed by Potze, et al. and Korotin, et al; this configuration should result in a distortion of the CoO6 octahedra (called a Jahn-Teller (JT) distortion). In the late '90s, Louca et al. reported neutron PDF results indicating a distorted Co-O environment, comparable to the Mn-O distortions observed in the similar manganite systems La1-yCayMnO3 (LCMO) and La1-zSrzMnO3 (LSMO). However, to date, these neutron PDF data for the cobaltites are the only structural results that support a JT distortion. While some recent experimental results are argued to be consistent with a large Co-O JT distortion and its associated IS state, many others appear to be inconsistent with such an interpretation. Our group at UC Santa Cruz, therefore took a closer look at the possibility of a JT distortion of the CoO6 octahedra, using a combination of the EXAFS and neutron PDF techniques; here we focus on the Co K-edge EXAFS results, for data collected at SSRL.
Results of the harmonics measurement program at the John F. Long photovoltaic house
Photovoltaic (PV) systems used in single-family dwellings require an inverter to act as an interface between the direct-current (dc) power output of the PV unit and the alternating-current (ac) power needed by house loads. A type of inverter known as line-commutated injects harmonic currents on the ac side and requires large amounts of reactive power. Large numbers of such PV installations could lead to unacceptable levels of harmonic voltages on the utility system, and the need to increase the utility's delivery of reactive power could result in significant cost increases. The harmonics and power-factor effects are examined for a single PV installation using a line-commutated inverter. The data were obtained during a five-day measurement program conducted at the John F. Long House, which is a prototype residential PV installation located in Phoenix, Arizona. The magnitude and phase of various currents and voltages from the fundamental to the 13th harmonic were recorded both with and without the operation of the PV system. The inverter can be looked upon as an ideal current source that injects definable amounts of current at any particular harmonic frequency; the harmonic currents that were normally conducted by the house loads underwent very little change as a result of currents injected by the inverter; the harmonic voltages seen by the house loads were slightly altered due to the passage of the inverter harmonic currents through system impedances, but no effect on the voltage harmonics was observed at the distribution transformer primary; and the inverter's reactive power demands more than doubled the maximum demand that would be expected for a normal home. Sufficient information was obtained to provide for a conservative modeling of a representative PV system to be used in a computer program designed to evaluate the effects of larger concentrations of PV systems.
Campen, G.L.
Surface harmonics method equations for solving the time-dependent neutron transport problems and their verification
Finite-difference time-dependent equations of Surface Harmonics method have been obtained for plane geometry. Verification of these equations has been carried out by calculations of tasks from 'Benchmark Problem Book ANL-7416'. The capacity and efficiency of the Surface Harmonics method have been demonstrated by solution of the time-dependent neutron transport equation in diffusion approximation. The results of studies showed that implementation of Surface Harmonics method for full-scale calculations will lead to a significant progress in the efficient solution of the time-dependent neutron transport problems in nuclear reactors. (authors)
Boyarinov, V. F.; Kondrushin, A. E.; Fomichenko, P. A. [National Research Center, Kurchatov Inst., Kurchatov Sq. 1, Moscow (Russian Federation)
Isotope effects in the harmonic response from hydrogenlike muonic atoms in strong laser fields
High-order harmonic generation from hydrogenlike muonic atoms exposed to ultraintense high-frequency laser fields is studied. Systems of low nuclear-charge number Z are considered where a nonrelativistic description applies. By comparing the radiative response for different isotopes, we demonstrate characteristic signatures of the finite nuclear mass and size in the harmonic spectra. In particular, for Z>1, an effective muon charge appears in the Schroedinger equation for the relative particle motion, which influences the position of the harmonic cutoff. Cutoff energies in the million-electron-volt domain can be achieved, offering prospects for the generation of ultrashort coherent {gamma}-ray pulses.
Shahbaz, Atif; Mueller, Carsten [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Buervenich, Thomas J. [Frankfurt Institute for Advanced Studies, Johann Wolfgang Goethe University, Ruth-Moufang-Strasse 1, D-60438 Frankfurt am Main (Germany)
Electro-optic harmonic conversion to switch a laser beam out of a cavity
The invention is a switch to permit a laser beam to escape a laser cavity through the use of an externally applied electric field across a harmonic conversion crystal. Amplification takes place in the laser cavity, and then the laser beam is switched out by the laser light being harmonically converted with dichroic or polarization sensitive elements present to alter the optical path of the harmonically converted laser light. Modulation of the laser beam can also be accomplished by varying the external electric field.
Haas, Roger A. (Pleasanton, CA); Henesian, Mark A. (Livermore, CA)
Spherical Harmonic Solutions to the 3D Kobayashi Benchmark Suite
Spherical harmonic solutions of order 5, 9 and 21 on spatial grids containing up to 3.3 million cells are presented for the Kobayashi benchmark suite. This suite of three problems with simple geometry of pure absorber with large void region was proposed by Professor Kobayashi at an OECD/NEA meeting in 1996. Each of the three problems contains a source, a void and a shield region. Problem 1 can best be described as a box in a box problem, where a source region is surrounded by a square void region which itself is embedded in a square shield region. Problems 2 and 3 represent a shield with a void duct. Problem 2 having a straight and problem 3 a dog leg shaped duct. A pure absorber and a 50% scattering case are considered for each of the three problems. The solutions have been obtained with Ardra, a scalable, parallel neutron transport code developed at Lawrence Livermore National Laboratory (LLNL). The Ardra code takes advantage of a two-level parallelization strategy, which combines message passing between processing nodes and thread based parallelism amongst processors on each node. All calculations were performed on the IBM ASCI Blue-Pacific computer at LLNL.
Brown, P.N.; Chang, B.; Hanebutte, U.R.
Energy transport by acoustic modes of harmonic lattices
We study the large scale evolution of a scalar lattice excitation which satisfies a discrete wave-equation in three dimensions. We assume that the dispersion relation associated to the elastic coupling constants of the wave-equation is acoustic, i.e., it has a singularity of the type |k| near the vanishing wave vector, k=0. To derive equations that describe the macroscopic energy transport we introduce the Wigner transform and change variables so that the spatial and temporal scales are of the order of epsilon. In the continuum limit, which is achieved by sending the parameter epsilon to 0, the Wigner transform disintegrates into three different limit objects: the transform of the weak limit, the H-measure and the Wigner-measure. We demonstrate that these three limit objects satisfy a set of decoupled transport equations: a wave-equation for the weak limit of the rescaled initial data, a dispersive transport equation for the regular limiting Wigner measure, and a geometric optics transport equation for the H-measure limit of the initial data concentrating to k=0. A simple consequence of our result is the complete characterization of energy transport in harmonic lattices with acoustic dispersion relations.
Lisa Harris; Jani Lukkarinen; Stefan Teufel; Florian Theil
Thermalization in harmonic particle chains with velocity flips
We propose a new mathematical tool for the study of transport properties of models for lattice vibrations in crystalline solids. By replication of dynamical degrees of freedom, we aim at a new dynamical system where the "local" dynamics can be isolated and solved independently from the "global" evolution. The replication procedure is very generic but not unique as it depends on how the original dynamics are split between the local and global dynamics. As an explicit example, we apply the scheme to study thermalization of the pinned harmonic chain with velocity flips. We improve on the previous results about this system by showing that after a relatively short time period the average kinetic temperature profile satisfies the dynamic Fourier's law in a local microscopic sense without assuming that the initial data is close to a local equilibrium state. The bounds derived here prove that the above thermalization period is at most of the order L^(2/3), where L denotes the number of particles in the chain. In particular, even before the diffusive time scale Fourier's law becomes a valid approximation of the evolution of the kinetic temperature profile. As a second application of the dynamic replica method, we also briefly discuss replacing the velocity flips by an anharmonic onsite potential.
Jani Lukkarinen
Time-frequency analysis and Harmonic Gaussian Functions
A method for time-frequency analysis is given. The approach utilizes properties of Gaussian distribution, properties of Hermite polynomials and Fourier analysis. We begin by the definitions of a set of functions called harmonic Gaussian functions. Then these functions are used to define a set of transformations,noted T_n, which associate to a function {\\psi},of the time variable t, a set of functions {\\Psi}_n which depend on time, frequency and frequency (or time) standard deviation. Some properties of the transformations T_n and the functions {\\Psi}_n are given. It is proved in particular that the square of the modulus of each function {\\Psi}_n can be interpreted as a representation of the energy distribution of the signal, represented by the function {\\psi}, in the time-frequency plane for a given value of the frequency (or time) standard deviation. It is also shown that the function {\\psi}, can be recovered from the functions{\\Psi}_n.
Tokiniaina Ranaivoson; Raoelina Andriambololona; Rakotoson Hanitriarivo
Correlation energies in distorted 3d-t{sub 2g} perovskite oxides
Using an effective low-energy Hamiltonian derived from the first-principles electronic structure calculations for the narrow t{sub 2g} bands of YTiO{sub 3}, LaTiO{sub 3}, YVO{sub 3}, and LaVO{sub 3}, we evaluate the contributions of the correlation energy E{sub c} to the stability of different magnetic structures that can be realized in these distorted perovskite oxides. We consider two approximations for E{sub c} that are based on regular perturbation theory expansion around a nondegenerate Hartree-Fock ground state. One is the second order of perturbation theory, which allows comparing the effects of local and nonlocal correlations. The other is the local t-matrix approach, which allows treating some higher-order contributions to E{sub c}. The correlation effects systematically improve the agreement with the experimental data and additionally stabilize the experimentally observed G- and C-type antifer-romagnetic (AFM) structures in YVO{sub 3} and LaVO{sub 3}, although the absolute magnitude of the stabilization energy is sensitive to the level of approximations and is somewhat smaller in the t-matrix method. The nonlocal correlations additionally stabilize the ferromagnetic ground state in YTiO{sub 3} and the C-type AFM ground state in LaVO{sub 3}. Among two inequivalent transition-metal sites in the monoclinic structure, the local correlations are stronger at the sites with the least distorted environment. Limitations of the regular perturbation-theory expansion for LaTiO{sub 3} are also discussed.
Solovyev, I. V. [National Institute for Materials Science (NIMS), Computational Materials Science Center (CMSC) (Japan)], E-mail: firstname.lastname@example.com
Correlation Energies in Distorted 3d-t2g Perovskite Oxides
Using an effective low-energy Hamiltonian derived from the first-principles electronic structure calculations for the narrow t2g bands of YTiO3, LaTiO3, YVO3, and LaVO3, we evaluate the contributions of the correlation energy (EC) to the stability of different magnetic structures, which can be realized in these distorted perovskite oxides. We consider two approximations for EC, which are based on the regular perturbation theory expansion around a nondegenerate Hartree-Fock ground state. One is the second order of perturbation theory, which allows us to compare the effects of local and nonlocal correlations. Another one is the local t-matrix approach, which allows us to treat some higher-order contributions to EC. The correlation effects systematically improve the agreement with the experimental data and additionally stabilize the experimentally observed G- and C-type antiferromagnetic (AFM) structures in YVO3 and LaVO3, though the absolute magnitude of the stabilization energy is sensitive to the level of approximations and somewhat smaller in the t-matrix method. The nonlocal correlations additionally stabilize the ferromagnetic ground state in YTiO3 and the C-type AFM ground state in LaVO3. Amongst two inequivalent transition-metal sites in the monoclinic structure, the local correlations are stronger at the sites with the least distorted environment. Limitations of the regular perturbation-theory expansion for LaTiO3 are also discussed. PACS: 71.10.-w; 71.15.Nc; 71.28.+d; 75.25.+z 1.
I. V. Solovyev
Frequency-tunable second-harmonic submillimeter-wave gyrotron oscillators
This thesis reports the design and experimental demonstration of frequency-tunable submillimeter-wave gyrotrons operating in continuous wave (CW) at the second harmonic of the electron cyclotron frequency. An unprecedented ...
Sousa, Antonio C. Torrezan de (Antonio Carlos Torrezan de)
Optimal Estimation of Spherical Harmonic Components from a Sample with Spatially Nonuniform Covariance Statistics
An optimal estimation technique is presented to estimate spherical harmonic coefficients. This technique is based on the minimization of the mean square error. This optimal estimation technique consists of computing optimal weights for a given ...
Kwang-Y. Kim; Gerald R. North; Samuel S. Shen
Fast Spherical Harmonic Transform Routine FLTSS Applied to the Shallow Water Test Set
The fast spherical harmonic transform algorithm proposed by Suda and Takami is evaluated in the solutions of the shallow water equation test set defined by Williamson et al. through replacing the Legendre transforms of the NCAR spectral transform ...
Reiji Suda
Relativistic second-harmonic generation of a laser from underdense plasmas
A high intensity laser obliquely incident on a vacuum-plasma interface produces second-harmonic radiation in the reflected component. The efficiency of second-harmonic generation increases with the angle of incidence, up to critical angle of incidence (our model is not valid beyond critical angle of incidence). The efficiency also depends on electron density, showing a maximum at {omega}{sub p}{sup 2}/{omega}{sup 2} congruent with 0.7, where {omega}{sub p} and {omega} are relativistic plasma frequency and laser frequency, respectively. The efficiency of second-harmonic generation increases sharply with laser intensity in the nonrelativistic regime and saturates at higher intensities. The intensity of the second harmonic is proportional to square of the laser intensity at low pump laser intensities and tends to proportional to laser intensity in the strong relativistic regime.
Singh, K.P.; Gupta, D.N.; Yadav, Sushila; Tripathi, V.K. [Computational Plasma Dynamics Laboratory, Mechanical Engineering, Kettering University, Flint, Michigan 48504 (United States); Department of Physics, Indian Institute of Technology, New Delhi 110016 (India)
A continuous-wave second harmonic gyrotron oscillator at 460 GHz
We report the short pulse and CW operation of a 460 GHz gyrotron oscillator both at the fundamental (near 230 GHz) and second harmonic (near 460 GHz) of electron cyclotron resonance. During operation in a complete CW regime ...
Hornstein, Melissa K. (Melissa Kristen), 1977-
The Harmonic Constant Datum Method: Options for Overcoming Datum Discontinuities at Mixed�Diurnal Tidal Transitions
The harmonic constant datum (HCD) method is a computationally efficient way of estimating tidal datums relative to mean sea level, without the need to compute long time series. However, datum discontinuities can occur between mixed and diurnal ...
Harold O. Mofjeld; Angie J. Venturato; Frank I. Gonz�lez; Vasily V. Titov; Jean C. Newman
Systematic Review and Harmonization of Life Cycle GHG Emission Estimates for Electricity Generation Technologies (Presentation)
This powerpoint presentation to be presented at the World Renewable Energy Forum on May 14, 2012, in Denver, CO, discusses systematic review and harmonization of life cycle GHG emission estimates for electricity generation technologies.
Heath, G.
High-efficiency second-harmonic generation in doubly-resonant ?[superscript (2)] microring resonators
By directly simulating Maxwell�s equations via the finite-difference time-domain (FDTD) method, we numerically demonstrate the possibility of achieving high-efficiency second harmonic generation (SHG) in a structure ...
Bi, Zhuan-Fang
Photovoltaic power converter system with a controller configured to actively compensate load harmonics
Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.
de Rooij, Michael Andrew (Clifton Park, NY); Steigerwald, Robert Louis (Burnt Hills, NY); Delgado, Eladio Clemente (Burnt Hills, NY)
run 873 - 7 September 1977, Rings 1 and 2 - 26 GeV, Orbit distortions due to sextupole fields with the low-beta insertion
Gourber, J P
Run 888 - 28 October 1977, Rings 1 and 2 - GeV, Orbit distortion due to sextupole fields with the low-beta insertion - part 2
Brand, K
High-order-harmonic generation in gas with a flat-top laser beam
We present experimental and numerical results on high-order-harmonic generation with a flat-top laser beam. We show that a simple binary tunable phase plate, made of two concentric glass plates, can produce a flat-top profile at the focus of a Gaussian infrared beam. Both experiments and numerical calculations show that there is a scaling law between the harmonic generation efficiency and the increase of the generation volume.
Boutu, W.; Auguste, T.; Binazon, L.; Gobert, O.; Carre, B. [Service des Photons, Atomes et Molecules, CEA-Saclay, FR-91191 Gif-sur-Yvette Cedex (France); Boyko, O.; Valentin, C. [Laboratoire d'Optique Appliquee, UMR 7639 ENSTA/CNRS/Ecole Polytechnique, FR-91761 Palaiseau (France); Sola, I.; Constant, E.; Mevel, E. [Universite de Bordeaux, CEA, CNRS UMR 5107, CELIA (Centre Lasers Intenses et Applications), FR-33400 Talence (France); Balcou, Ph. [Laboratoire d'Optique Appliquee, UMR 7639 ENSTA/CNRS/Ecole Polytechnique, FR-91761 Palaiseau (France); Universite de Bordeaux, CEA, CNRS UMR 5107, CELIA (Centre Lasers Intenses et Applications), FR-33400 Talence (France); Merdji, H. [Service des Photons, Atomes et Molecules, CEA-Saclay, FR-91191 Gif-sur-Yvette Cedex (France); PULSE Institute for Ultrafast Energy Science, Stanford Linear Accelerator Center, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025 (United States)
High-harmonic XUV source for time- and angle-resolved photoemission spectroscopy
We present a laser-based apparatus for visible pump/XUV probe time- and angle-resolved photoemission spectroscopy (TRARPES) utilizing high-harmonic generation from a noble gas. Femtosecond temporal resolution for each selected harmonic is achieved by using a time-delay-compensated monochromator (TCM). The source has been used to obtain photoemission spectra from insulators (UO{sub 2}) and ultrafast pump/probe processes in semiconductors (GaAs).
Dakovski, Georgi L [Los Alamos National Laboratory; Li, Yinwan [Los Alamos National Laboratory; Durakiewicz, Tomasz [Los Alamos National Laboratory; Rodriguez, George [Los Alamos National Laboratory
First Harmonic (2f) Characterisation of Resonant Frequency and Q-Factor of Micromechanical Transducers
In this paper, the response to the first harmonic component (2f) of the electrostatic force in single terminal driven electrostatic comb-drive and parallel-plate drive was used as a signal to extract device parameters, namely, the Q-factor and ... Keywords: Lorentzian curve-fitting, electrostatic drive, experimental modal analysis, first harmonic (2f), lock-in technique, resonance curve area (RCA)
V. J. Logeeswaran; F. E. H. Tay; M. L. Chan; F. S. Chau; Y. C. Liang
Well-posed initial-boundary value problem for the harmonic Einstein equations using energy estimates
In recent work, we used pseudo-differential theory to establish conditions that the initial-boundary value problem for second order systems of wave equations be strongly well-posed in a generalized sense. The applications included the harmonic version of the Einstein equations. Here we show that these results can also be obtained via standard energy estimates, thus establishing strong well-posedness of the harmonic Einstein problem in the classical sense.
H. -O. Kreiss; O. Reula; O. Sarbach; J. Winicour
Program on Technology Innovation: Evaluation of a Commercial Device for Measurement of Residential Transients and Harmonics
This report describes laboratory testing to evaluate the technical performance of the Microsurge Stetzer meter, a commercially available device for measuring electrical transients and harmonics on residential circuits. This device has been developed to measure low-level unwanted signals (higher-frequency harmonics and transients) introduced onto 50/60 Hz household mains through normal operation of appliances within the home and through other environmental signals and transients usually present on ...
Harmonic mode competition in a terahertz gyrotron backward-wave oscillator
Electron cyclotron maser interactions at terahertz (THz) frequencies require a high-order-mode structure to reduce the wall loss to a tolerable level. To generate THz radiation, it is also essential to employ cyclotron harmonic resonances to reduce the required magnetic field strength to a value within the capability of the superconducting magnets. However, much weaker harmonic interactions in a high-order-mode structure lead to serious mode competition problems. The current paper addresses harmonic mode competition in the gyrotron backward wave oscillator (gyro-BWO). We begin with a comparative study of the mode formation and oscillation thresholds in the gyro-BWO and gyromonotron. Differences in linear features result in far fewer 'windows' for harmonic operation of the gyro-BWO. Nonlinear consequences of these differences are examined in particle simulations of the multimode competition processes in the gyro-BWO, which shed light on the competition criteria between modes of different as well as the same cyclotron harmonic numbers. The viability of a harmonic gyro-BWO is assessed on the basis of the results obtained.
Kao, S. H.; Chiu, C. C.; Chang, P. C.; Wu, K. L.; Chu, K. R. [Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)
Multidimensional high harmonic spectroscopy: A semi-classical perspective on measuring multielectron rearrangement upon ionization
High harmonic spectroscopy has the potential to combine attosecond temporal with sub-Angstrom spatial resolution of the early nuclear and multielectron dynamics in molecules. It involves strong field ionization of the molecule by the IR laser field followed by time-delayed recombination of the removed electron with the molecular ion. The time-delay is controlled on the attosecond time scale by the oscillation of the IR field and is mapped into the harmonic number, providing a movie of molecular dynamics between ionization and recombination. One of the challenges in the analysis of high harmonic signal stems from the fact that the complex dynamics of both ionization and recombination with their multiple observables are entangled in the harmonic signal. Disentangling this information requires multidimensional approach, capable of mapping ionization and recombination dynamics into different independent parameters. We suggest multidimensional high harmonic spectroscopy as a tool for characterizing of ionization and recombination processes separately allowing for simultaneous detection of both the ionization delays and sub-cycle ionization rates. Our method extends the capability of the two dimensional (2D) set-up suggested recently by Shafir et al on reconstructing ionization delays, while keeping the reconstruction procedure as simple as in the original proposal. The scheme is based on the optimization of the high harmonic signal in orthogonally polarized strong fundamental and relatively weak multicolour control fields.
Valeria Serbinenko; Olga Smirnova
Flow Distortion by a Solent Sonic Anemometer: Wind Tunnel Calibration and Its Assessment for Flux Measurements over Forest and Field
Main flow distortion effects caused by the sonic probe (i.e., deflection and attenuation/amplification of the wind vector) as a function of the azimuth angle of the incoming flow were examined by means of wind tunnel measurements at four ...
A. Grelle; A. Lindroth
Spectral restoration from low signal-to-noise, distorted NMR signals: application to hyphenated capillary electrophoresis-NMR
Spectral restoration from low signal-to-noise, distorted NMR signals: application to hyphenated capillary electrophoresis-NMR Yu Li,a,b Michael E. Lacey,b,c Jonathan V. Sweedler,b,c and Andrew G. Webba; revised 11 February 2003 Abstract In capillary electrophoresis separations coupled to NMR signal detection
Andrews, Anne M.
Effect of two-phase natural circulation distortion on tube failure in steam boilers
Two different cases of evaporator tube ruptures in power station boilers due to natural circulation distortion are presented. The first case discussed concerns a 110-MW/sub e/ unit boiler with bottom evaporation tubing inclined at 15/sup 0/ to the horizontal. At the high heat fluxes present in the furnace, subcooled boiling occurs in inclined tubes. For these inclinations an insufficient flow rate causes local heat transfer deficiencies due to vapor-water separation. The introduction of internally finned tubes eliminates local heat transfer deficiencies and prevents further tube failures. The second case is that of circulation interruption due to blowdown during start-up. The water level in the drum of this second 110-MW/sub e/ unit boiler was controlled by inlet header blowdown during start-up. Thus, natural circulation was interrupted, causing local overheating of evaporator tubing. The event was identified by an increase of the tube rupture frequency. After changing the blowdown procedure, the interruptions of natural circulation were avoided and the tube failure frequency decreased substantially.
Afgan, N.; Radovanovic, P.; Brajuskovic, B.
Control of high-order harmonics for attoscience using a static-electric-field pattern
Quantum control in high-order-harmonic generation is considered theoretically by using a spatial distribution of static electric fields along the propagation direction of the driving field. It is shown that the trajectories of the electrons during its acceleration by the laser field in the high-harmonics-generation process can be controlled by periodically distributed static electric fields, which conveniently shape the driving laser field during propagation. Applying this mechanism, a quasi-phase-matching scheme that leads to filtered enhanced high harmonics is achieved. The harmonics in the plateau region are enhanced due to periodical phase variations in the long quantum trajectories as a consequence of the faster change experienced by the intensity-dependent phase along the longer electron trajectories. This effect should be observed in all quasi-phase-matching schemes based on perturbation of the microscopic quantum phase. The richness of adding a static-electric-field spatial pattern in the interaction region suggests a general scheme for feedback loop control in high-order-harmonic generation.
Serrat, Carles [UPC-Universitat Politecnica de Catalunya, Colom 11, E-08222 Terrassa (Barcelona) (Spain)
The effects of supply harmonics on the performance of compact fluorescent lamps
This paper describes a performance evaluation of ten compact fluorescent lighting systems operated with sinusoidal and distorted voltage waveform conditions. The lamps were either provided with an electronic ballast, a magnetic core ballast or a magnetic core ballast with a power factor correction circuit. The test results show that the electrical performance of the compact fluorescent lamps for both sinusoidal and distorted voltage waveform operation is related to the different types of ballast used. The cost of operation of these compact fluorescent lamps was calculated and compared to the cost of a conventional 60 W incandescent lamp.
Arseneau, R.; Ouellette, M.
The Harmonic and Sideband Structure of the Kilohertz Quasi-Periodic Oscillations in Sco X-1
We use data from the Rossi X-ray Timing Explorer to search for harmonics and sidebands of the two simultaneous kilohertz quasi-periodic oscillations (kHz QPOs) in Sco X-1. We do not detect any of these harmonics or sidebands, with 95% confidence upper limits to their power between ~ 1% and ~ 10% of the power of the upper kHz QPO. The oscillations produced at these frequencies may be attenuated in a scattering corona around the neutron star. We find that upper limits to the unattenuated power of some of the strongest theoretically predicted harmonics and sidebands are as low as ~ 2% of the unattenuated power of the high-frequency QPO in Sco X-1.
Mariano Mendez; Michiel van der Klis
Modeling of large aperture third harmonic frequency conversion of high power Nd:glass laser systems
To provide high-energy, high-power beams at short wavelengths for inertial-confinement-fusion experiments, we routinely convert the 1.053-{mu}m output of the Nova, Nd:phosphate-glass, laser system to its third-harmonic wavelength. We describe performance and conversion efficiency modeling of the 3 {times} 3 arrays potassium-dihydrogen-phosphate crystal plates used for type II/type II phase-matched harmonic conversion of Nova 0.74-m diameter beams, and an alternate type I/type II phase-matching configuration that improves the third-harmonic conversion efficiency. These arrays provide energy conversion of up to 65% and intensity conversion to 70%. 19 refs., 11 figs.
Henesian, M.A.; Wegner, P.J.; Speck, D.R.; Bibeau, C.; Ehrlich, R.B.; Laumann, C.W.; Lawson, J.K.; Weiland, T.L.
Optimisation of An HHG-Seeded Harmonic Cascade FEL Design for the NLS Project
Optimization studies of an HHG-seeded harmonic cascade FEL design for the UK's proposed New Light Source (NLS) facility are presented. Three separate FELs are planned to meet the requirements for continuous coverage of the photon energy range 50-1000 eV with variable polarization, 20 fs pulse widths and good temporal coherence. The design uses an HHG seed source tuneable from 50-100 eV to provide direct FEL seeding in this range, and one or two stage harmonic cascades to reach the higher photon energies. Studies have been carried out to optimize a harmonic cascade FEL operating at 1 keV; topics investigated include modulator configuration, seed power level and ef- fects of the HHG seed structure. FEL simulations using realistic electron beam distributions are presented and tolerance to increased emittance has been considered.
Dunning, David; /Daresbury; Thompson, Neil; /Daresbury; Bartolini, Riccardo; /Oxford U., JAI; Geng, Huiping; /SLAC; Huang, Zhirong; /SLAC; McNeil, Brian; /Strathclyde U.
Nonlinear harmonic generation and devices in doubly-resonant Kerr cavities
We describea theoretical analysis of the nonlinear dynamics of third-harmonic generation ($\\omega\\to3\\omega$) via Kerr ($\\chithree$) nonlinearities in a resonant cavity with resonances at both $\\omega$ and $3\\omega$. Such a doubly resonant cavity greatly reduces the required power for efficient harmonic generation, by a factor of $\\sim V/Q^2$ where $V$ is the modal volume and $Q$ is the lifetime, and can even exhibit 100% harmonic conversion efficiency at a critical input power. However, we show that it also exhibits a rich variety of nonlinear dynamics, such as multistable solutions and long-period limit cycles.We describe how to compensate for self/cross-phase modulation (which otherwise shifts the cavity frequencies out of resonance), and how to excite the different stable solutions (and especially the high-efficiency solutions) by specially modulated input pulses.
Hashemi, Hila; Joannopoulos, J D; Soljači�?, Marin; Johnson, Steven G
Dynamic Analysis of Wind Turbine Planetary Gears Using an Extended Harmonic Balance Approach: Preprint
The dynamics of wind turbine planetary gears with gravity effects are investigated using an extended harmonic balance method that extends established harmonic balance formulations to include simultaneous internal and external excitations. The extended harmonic balance method with arc-length continuation and Floquet theory is applied to a lumped-parameter planetary gear model including gravity, fluctuating mesh stiffness, bearing clearance, and nonlinear tooth contact to obtain the planetary gear dynamic response. The calculated responses compare well with time domain integrated mathematical models and experimental results. Gravity is a fundamental vibration source in wind turbine planetary gears and plays an important role in system dynamics, causing hardening effects induced by tooth wedging and bearing-raceway contacts. Bearing clearance significantly reduces the lowest resonant frequencies of translational modes. Gravity and bearing clearance together lowers the speed at which tooth wedging occurs lower than the resonant frequency.
Guo, Y.; Keller, J.; Parker, R. G.
High-order harmonic generation with Rydberg atoms by using an intense few-cycle pulse
We demonstrate that high-order harmonic generation (HHG) with both high cutoff frequency and high conversion efficiency can be realized by using a Rydberg atom in a few-cycle laser pulse. This is because a Rydberg state has a large electron orbital radius and small binding energy; therefore an electron in the Rydberg state can be ionized easily and accelerated directly toward the core under the interaction of a few-cycle laser pulse, leading to emission of harmonic photons. In this case, the tunneling process of the electron is not involved and, hence, the conversion efficiency and the cutoff frequency of harmonic generation can be higher than that predicted by the conventional three-step model.
Zhai Zhen; Fu Panming; Wang Bingbing [Laboratory of Optical Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080 (China); Zhu Qiren [Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012 (China); Chen Jing [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yan Zongchao [Department of Physics, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3 (Canada)
Analysis of periodically-forced turbulence in the rapid distortion limit
Rapid Distortion Theory is used to perform calculations of unsteadily-forced initially isotropic turbulence so that the physics of such flows can be better understood. The results of these calculations show that there are three distinct regimes of physical behavior for the kind of turbulence that we are considering: (1) turbulence that is forced at a relatively low frequency in which the kinetic energy settles down to a constant value at later times, (2) turbulence that is forced at a slightly higher frequency in which the kinetic energy value oscillates for a time, but then increases dramatically, and (3) turbulence that is forced at a relatively high frequency in which the kinetic energy evolution exhibits a periodic behavior. To better understand the role of the rapid pressure-strain correlation, these results are also compared to Inertial Model results for the same set of forcing frequencies. The results of this comparison show that the rapid pressure plays a key role in determining the stability characteristics of unsteadily-forced turbulence. The evolution equation for kinetic energy is then used to propose a model that describes the behavior approximately in terms of a time lag between applied mean strain and the Reynolds stress. This model suggests that the different responses under the different frequencies of forcing correspond to different stress-strain time lags. Overall, then the results indicate that rapid pressure serves to create a time lag between applied stress and strain, and it is the extent of this time lag that causes turbulence to respond differently under various frequencies of forcing.
O'Neil, Joshua Robert
Rhombohedrally Distorted ?-Au5-xZn8+y Phases in the Au-Zn System
The region of the Au�Zn phase diagram encompassing ?-brass-type phases has been studied experimentally from 45 to 85 atom % Zn. The ? phases were obtained directly from the pure elements by heating to 680 �C in evacuated silica tubes, followed by annealing at 300 �C. Powder X-ray and single-crystal diffraction studies show that ?-�Au5Zn8� phases adopt a rhombohedrally distorted Cr5Al8 structure type rather than the cubic Cu5Zn8 type. The refined compositions from two single crystals extracted from the Zn- and Au-rich loadings are Au4.27(3)Zn8.26(3)?0.47 (I) and Au4.58(3)Zn8.12(3)?0.3 (II), respectively (? = vacancy). These (I and II) refinements indicated both nonstatistical mixing of Au and Zn atoms as well as partially ordered vacancy distributions. The structures of these ? phases were solved in the acentric space group R3m (No. 160, Z = 6), and the observed lattice parameters from powder patterns were found to be a = 13.1029(6) and 13.1345(8) � and c = 8.0410(4) and 8.1103(6) � for crystals I and II, respectively. According to single-crystal refinements, the vacancies were found on the outer tetrahedron (OT) and octahedron (OH) of the 26-atom cluster. Single-crystal structural refinement clearly showed that the vacancy content per unit cell increases with increasing Zn, or valence-electron concentration. Electronic structure calculations, using the tight-binding linear muffin-tin orbital method with the atomic-sphere approximation (TB-LMTO-ASA) method, indicated the presence of a well-pronounced pseudogap at the Fermi level for �Au5Zn8� as the representative composition, an outcome that is consistent with the Hume�Rothery interpretation of ? brass.
Thimmaiah, Srinivasa [Ames Laboratory; Miller, Gordon J. [Ames Laboratory
Application of Elliott's SU(3) model to the triaxially deformed harmonic oscillators
We have introduced new bosons corresponding to the integral ratio of three frequencies for a harmonic oscillator potential, by means of a non-linear transformation which realizes the SU(3) group as a dynamical symmetry group, and which leaves the anisotropic harmonic oscillator Hamiltonian invariant. The classification of the single-particle levels based on this covering group predicts magic numbers depending on the deformation parameters {delta} and {gamma}. The special cases with tan {gamma} = 1/{radical}(3)({gamma} = 30 deg.) and {radical}(3)/5({gamma}{approx}19 deg.) are discussed.
Sugawara-Tanabe, Kazuko [Otsuma Women's University, Tama, Tokyo 206-8540 (Japan); Theoretical Nuclear Physics Laboratory, RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan)
A method for reducing harmonics in output voltages of a double-connected inverter
A new method for reducing harmonics involved in output voltages of the double-connected inverter is proposed. By adding four auxiliary switching devices and an interphase transformer with secondary winding to the conventional 12-step inverter, output voltages of the proposed circuit can be almost the same waveforms as a conventional 36-step inverter. In this paper, circuit performances and output voltage waveforms are discussed, and the optimum parameters are derived. Then, effects on harmonic reductions can be clarified by theoretical and experimental results, and ratings of system components are investigated.
Masukawa, Shigeo; Iida, Shoji (Tokyo Denki Univ., Tokyo (Japan). Dept. of Electrical Engineering)
Life Cycle GHG Emissions from Conventional Natural Gas Power Generation: Systematic Review and Harmonization (Presentation)
This research provides a systematic review and harmonization of the life cycle assessment (LCA) literature of electricity generated from conventionally produced natural gas. We focus on estimates of greenhouse gases (GHGs) emitted in the life cycle of electricity generation from conventionally produced natural gas in combustion turbines (NGCT) and combined-cycle (NGCC) systems. A process we term "harmonization" was employed to align several common system performance parameters and assumptions to better allow for cross-study comparisons, with the goal of clarifying central tendency and reducing variability in estimates of life cycle GHG emissions. This presentation summarizes preliminary results.
Heath, G.; O'Donoughue, P.; Whitaker, M.
IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 45, NO. 11, NOVEMBER 2009 1465 Cerenkov-Type Second-Harmonic Generation in
IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 45, NO. 11, NOVEMBER 2009 1465 Cerenkov-Type Second the Cerenkov-type second-harmonic gen- eration in several different two-dimensional nonlinear photonic observe either single or double Cerenkov-like second-harmonic rings. We discuss the properties
Modeling and simulation of a single phase photovoltaic inverter and investigation of switching strategies for harmonic minimization
The aim of this paper is to build an EMTDC model of a single phase photovoltaic inverter and to investigate switching strategies for harmonic minimisation. For the simulation of this model, the PSCAD/EMTDC software package was used and the waveforms ... Keywords: EMTDC model, harmonic minimization, single-phase photovoltaic inverter
St. Kourtesi; L. Ekonomou; A. Nakulas; G. P. Fotis; E. Zoulias
Reynolds and Favre-averaged rapid distortion theory for compressible, ideal-gas turbulence
Compressible ideal-gas turbulence subjected to homogeneous shear is investigated at the rapid distortion limit. Specific issues addressed are (i) the interaction between kinetic and internal energies and role of pressure-dilatation; (ii) the modifications to pressure-strain correlation and Reynolds stress anisotropy and (iii) the effect of the composition of velocity fluctuations (solenoidal vs. dilatational). Turbulence evolution is found to be strongly influenced by gradient Mach number, the initial solenoidal-to-dilatational ratio of the velocity field and the initial intensity of the thermodynamic fluctuations. The balance between the initial fluctuations in velocity and thermodynamic variables is also found to be very important. Any imbalance in the two fluctuating fields leads to high levels of pressure-dilatation and intense exchange. For a given initial condition, it is found that the interaction via the pressuredilatation term between the momentum and energy equations reaches a peak at an intermediate gradient Mach number. The energy exchange between internal and kinetic modes is negligible at very high or very low Mach number values due to lack of pressure dilatation. When present, the exchange exhibits oscillations even as the sum of the two energies evolves smoothly. The interaction between shear and solenoidal initial velocity field generates dilatational fluctuations; for some intermediate levels of shear Mach number dilatational fluctuations account for 20% of the total fluctuations. Similarly, the interaction between shear and initial dilatation produces solenoidal oscillations. Somewhat surprisingly, the generation of solenoidal fluctuations increases with gradient Mach number. Larger levels of pressure-strain correlation are seen with dilatational rather than solenoidal initial conditions. Anisotropies of solenoidal and dilatational components are investigated individually. The most interesting observation is that solenoidal and dilatational turbulence tend toward a one componential state but the energetic component is different in each case. As in incompressible shear flows, with solenoidal fluctuations, the streamwise (1,1) component of Reynolds stress is dominant. With dilatational fluctuations, the stream-normal (2,2) component is the strongest. Overall, the study yields valuable insight into the linear processes in high Mach number shear flows and identifies important closure modeling issues.
Lavin, Tucker Alan
Spectral analysis of non-commutative harmonic oscillators: the lowest eigenvalue and no crossing
The lowest eigenvalue of non-commutative harmonic oscillators $Q$ is studied. It is shown that $Q$ can be decomposed into four self-adjoint operators, and all the eigenvalues of each operator are simple. We show that the lowest eigenvalue $E$ of $Q$ is simple. Furthermore a Jacobi matrix representation of $Q$ is given and spectrum of $Q$ is considered numerically.
Fumio Hiroshima; Itaru Sasaki
Social-Psychological harmonic oscillators in the self-regulation of organizations and systems
We propose ab initio the existence of social-psychological harmonic oscillators (SPHO) acting computationally in the minds of an intelligent audience that a self-regulated collective exploits to solve problems, resolve complex issues, or entertain ... Keywords: conservation of information, incomplete information, interdependence
William F. Lawless; Donald A. Sofge
A Multilevel Active Front-End Rectifier With Current Harmonic Compensation Capability
transformation. By controlling id and iq at the rectifier input side, the active and reactive power absorbed-q transformation requires a more complex hardware and software implementation. The power circuit topology-end rectifier that can absorb current harmonics generated by nonlinear loads connected to the same power
Rudnick, Hugh
A new spherical harmonics scheme for multi-dimensional radiation transport I. Static matter configurations
Recent work by McClarren and Hauck (2010) [31] suggests that the filtered spherical harmonics method represents an efficient, robust, and accurate method for radiation transport, at least in the two-dimensional (2D) case. We extend their work to the ... Keywords: Asymptotic diffusion limit, Discontinuous Galerkin, PN-method, Radiation transport
David Radice, Ernazar Abdikamalov, Luciano Rezzolla, Christian D. Ott
Harmonic Generation at Lower Electron Energies for a Hard X-ray FEL
There are several schemes currently being investigated to pre-bunch the electron beam and step the coherent bunching up to higher harmonics, all which require modulator sections which introduce additional energy modulation. X-ray FELs operate in a regime where the FEL parameter, {rho} is equal to or less than the effective energy spread introduced from the emittance in the electron beam. Because of this large effective energy spread, the energy modulation introduced from harmonic generation schemes would seriously degrade FEL performance. This problem can be mitigated by incorporating the harmonic generation scheme at a lower electron kinetic energy than the energy at the final undulator. This will help because the effective energy spread from emittance is reduced at lower energies, and can be further reduced by making the beam transversely large. Then the beam can be squeezed down slowly enough in the subsequent accelerator sections so that geometric debunching is mitigated. The beam size inside the dispersive chicanes and in the accelerator sections must be carefully optimized to avoid debunching, and each subharmonic modulator section must generate enough energy modulation to overcome the SASE noise without significantly increasing the gain length in the final undulator. Here we show analytical results that demonstrate the feasibility of this harmonic pre-bunching scheme.
Marksteiner, Quinn R. [Los Alamos National Laboratory
High conversion efficiency pumped-cavity second harmonic generation of a diode laser
To investigate the feasibility of producing a compact, efficient blue laser source, pumped-cavity second harmonic generation of diode lasers was explored. It is desirable to have such lasers to increase optical disk storage density, for color displays and for under-the-sea green-blue optical signal transmission. Based on assumed cavity losses, a cavity was designed and numerical analysis predicted an overall conversion efficiency to the second harmonic wavelength of 76% from a 75 mW diode laser. The diode laser used in these experiments had a single longitudinal and a single transverse mode output at 860 nm. The best conversion efficiency obtained (26%) was less than optimum due to the 2.5% single-pass linear losses associated with the cavity. However, calculations based on these higher losses are in good agreement with the experimentally determined values. In additions, a factor of 1.65 increase in the second harmonic output power is anticipated by reducing the input mirror reflectivity to better impedance-match the cavity. With this relatively low second harmonic conversion, the power to light conversion is 7.8%.
Keicher, D.M.
Fabrication of band-gap structures in planar nonlinear waveguides for second harmonic generation
The work presented here deals with the design and fabrication of the linear grating on a LiNbO3 planar waveguide to obtain an efficient second harmonic generation operating in Cerenkov configuration. The lithium niobate is a nonlinear material ... Keywords: e-beam lithography, nonlinear optics
V. Foglietti; E. Cianci; D. Pezzetta; C. Sibilia; M. Marangoni; R. Osellame; R. Ramponi
Transient and harmonic voltages associated with automated capacitor switching on distribution systems
One of the functions proposed for distribution automation systems is automated capacitor switching to control power factor and voltage profile on feeder circuits. This is one of the functions being implemented as part of the Athens Automation and Control Experiment on the Athens Utilities Board (AUB) in Athens, Tennessee. A concern with automated capacitor switching is the increase in harmonic and transient voltages due to different capacitor configurations on the distribution system. A study was performed to evaluate the impact of the automated capacitor switching on the AUB distribution system. The study has identified problem areas, methods for determining the problem areas, and possible solutions. The substation capacitor banks were found to be the dominant factor in both the transient and harmonic responses of the distribution system. The harmonic response of the system is dominated by the parallel inductance/capacitance of the circuit comprised of the substation capacitor and equivalent source reactance at the substation. The transient analyses indicated that when the substation capacitor is energized, magnified transient voltages can occur at switched-in feeder capacitors. An evaluation of the effect of automated capacitor switching is necessary to properly design the automated capacitor switching schemes and the required arrester protection for any harmonic and/or transient overvoltage contingency.
Rizy, D.T.; Gunther, E.W.; Mc Granaghan, M.F.
One of the functions proposed for distribution system automation is automated capacitor switching to control power factor and voltage profile on feeder circuits. This is one of the functions being implemented as part of the Athens Automation and Control Experiment on the Athens Utilities Board (AUB) in Athens, Tennessee. A concern with automated capacitor switching is the increase in harmonic and transient voltages due to different capacitor configurations on the distribution system. A study was performed to evaluate the impact of the automated capacitor switching on the AUB distribution system. The study has identified problem areas, methods for determining the problem areas and possible solutions. The substation capacitor banks were found to be the dominant factor in both the transient and harmonic responses of the distribution system. The harmonic response of the system is dominated by the parallel inductance/capacitance of the circuit comprised of the substation capacitor and equivent source reactance at the substation. The transient analyses found that when the substation capacitor is energized, magnified transient voltages can occur at switched in feeder capacitors. An evaluation of the effect of automated capacitor switching is necessary to properly design tha automated capacitor switching schemes and the required arrester protection for any harmonic and/or transient overvoltage contingency.
Rizy, D.T.; Gunther, E.W.; McGranaghan, M.F.
Wave absorption at the second harmonic of the electron-cyclotron frequency in a tokamak plasma
Wave absorption in the ISX-B tokamak (Phys. Rev. Lett. 44, 647 (1980)) at the second harmonic (..omega.. = 2..omega../sub c/e) of the electron-cyclotron frequency is reported. Measurements of the absorption of a wave polarized in the extraordinary mode and propagating perpendicular to the toroidal magnetic field are in agreement with computations.
McDermott, F.S.; Bekefi, G.; England, A.C.; Attenberger, S.E.; Batchelor, D.B.; Edmonds, P.H.; Goldfinger, R.C.; Kindsfather, R.R.; Lazarus, E.A.; Murakami, M.
Three-halves harmonic emission from a laser filament in a plasma channel
A self-trapped laser filament is susceptible to decay-producing radially localized Langmuir waves. A nonlinear interaction of the pump wave with the density oscillation at the Langmuir frequency gives rise to three-halves harmonic emissions. Using a basis-function expansion technique, the emitted power in the backward direction is obtained. It decreases with the increasing size of the filament.
Mishra, G.; Talukdar, I.; Tripathi, V.; Tripathi, V.K. (Indian Inst. of Tech., New Delhi (India). Dept. of Physics)
A Harmonic-Fourier Spectral Limited-Area Model with an External Wind Lateral Boundary Condition
In comparison to the Tatsumi�s spectral method, the harmonic-Fourier spectral method has two major advantages. 1) The semi-implicit scheme is quite efficient because the solutions of the Poisson and Helmholtz equations are readily derived. 2) The ...
Qiu-shi Chen; Le-sheng Bai; David H. Bromwich
High-order harmonics from bow wave caustics driven by a high-intensity laser
We propose a new mechanism of high-order harmonic generation during an interaction of a high-intensity laser pulse with underdense plasma. A tightly focused laser pulse creates a cavity in plasma pushing electrons aside and exciting the wake wave and the bow wave. At the joint of the cavity wall and the bow wave boundary, an annular spike of electron density is formed. This spike surrounds the cavity and moves together with the laser pulse. Collective motion of electrons in the spike driven by the laser field generates high-order harmonics. A strong localization of the electron spike, its robustness to oscillations imposed by the laser field and, consequently, its ability to produce high-order harmonics is explained by catastrophe theory. The proposed mechanism explains the experimental observations of high-order harmonics with the 9 TW J-KAREN laser (JAEA, Japan) and the 120 TW Astra Gemini laser (CLF RAL, UK) [A. S. Pirozhkov, et al., arXiv:1004.4514 (2010); A. S. Pirozhkov et al, AIP Proceedings, this volume]. The theory is corroborated by high-resolution two-and three-dimensional particle-in-cell simulations.
Pirozhkov, A.S.; Kando, M.; Esirkepov, T.Zh. [Advanced Beam Technology Division, Japan Atomic Energy Agency (Japan); and others
SMI 2011: Full Paper: Interactive 3D caricature from harmonic exaggeration
A common variant of caricature relies on exaggerating characteristics of a shape that differs from a reference template, usually the distinctive traits of a human portrait. This work introduces a caricature tool that interactively emphasizes the differences ... Keywords: Caricature, GPU, Interactive, Manifold harmonics, Modeling
Thomas Lewiner; Thales Vieira; Dimas Mart�nez; Adelailson Peixoto; Vin�cius Mello; Luiz Velho
Continuous vs. discrete models for the quantum harmonic oscillator and the hydrogen atom
The Kravchuk and Meixner polynomials of discrete variable are introduced for the discrete models of the harmonic oscillator and hydrogen atom. Starting from Rodrigues formula we construct raising and lowering operators, commutation and anticommutation relations. The physical properties of discrete models are figured out through the equivalence with the continuous models obtained by limit process.
M. Lorente
Analysis of system wide distortion in an integrated power system utilizing a high voltage DC bus and silicon carbide power devices
This research investigates the distortion on the electrical distribution system for a high voltage DC Integrated Power System (IPS). The analysis was concentrated on the power supplied to a propulsion motor driven by an ...
Fallier, William F. (William Frederick)
Life Cycle Greenhouse Gas Emissions of Crystalline Silicon Photovoltaic Electricity Generation: Systematic Review and Harmonization
Published scientific literature contains many studies estimating life cycle greenhouse gas (GHG) emissions of residential and utility-scale solar photovoltaics (PVs). Despite the volume of published work, variability in results hinders generalized conclusions. Most variance between studies can be attributed to differences in methods and assumptions. To clarify the published results for use in decision making and other analyses, we conduct a meta-analysis of existing studies, harmonizing key performance characteristics to produce more comparable and consistently derived results. Screening 397 life cycle assessments (LCAs) relevant to PVs yielded 13 studies on crystalline silicon (c-Si) that met minimum standards of quality, transparency, and relevance. Prior to harmonization, the median of 42 estimates of life cycle GHG emissions from those 13 LCAs was 57 grams carbon dioxide equivalent per kilowatt-hour (g CO{sub 2}-eq/kWh), with an interquartile range (IQR) of 44 to 73. After harmonizing key performance characteristics, irradiation of 1,700 kilowatt-hours per square meter per year (kWh/m{sup 2}/yr); system lifetime of 30 years; module efficiency of 13.2% or 14.0%, depending on module type; and a performance ratio of 0.75 or 0.80, depending on installation, the median estimate decreased to 45 and the IQR tightened to 39 to 49. The median estimate and variability were reduced compared to published estimates mainly because of higher average assumptions for irradiation and system lifetime. For the sample of studies evaluated, harmonization effectively reduced variability, providing a clearer synopsis of the life cycle GHG emissions from c-Si PVs. The literature used in this harmonization neither covers all possible c-Si installations nor represents the distribution of deployed or manufactured c-Si PVs.
Hsu, D. D.; O'Donoughue, P.; Fthenakis, V.; Heath, G. A.; Kim, H. C.; Sawyer, P.; Choi, J. K.; Turney, D. E.
VII Hotine-Marussi Symposium on Theoretical Geodesy, 6-10 July 2009, Rome, Italy. Performance analysis of isotropic spherical harmonic spectral windows
analysis of isotropic spherical harmonic spectral windows B. Devaraju and N. Sneeuw Institute of Geodesy isotropic spherical harmonic spectral windows in the spa- tial domain. The parameters are devised in order to answer the following question: If an isotropic spherical harmonic window is applied in the spectral
Stuttgart, Universität
Modeling of Synergy Between 4th and 6th Harmonic Absorptions of Fast Waves on Injected Beams in DIII-D Tokamak
In recent moderate to high harmonic fast wave heating and current drive experiments in DIII-D, a synergy effect was observed when the 6{sup th} harmonic 90 MHz fast wave power is applied to the plasma preheated by neutral beams and the 4{sup th} harmonic 60 MHz fast wave. In this paper, we investigate how the synergy can occur using ORBIT-RF coupled with AORSA. Preliminary simulations suggest that damping of 4{sup th} harmonic FW on beam ions accelerates them above the injection energy, which may allow significant damping of 6{sup th} harmonic FW on beam ion tails to produce synergy.
Choi, M.; Pinsker, R. I.; Chan, V. S. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Muscatello, C. M. [University of California-Irvine, Irvine, California, 92697 (United States); Jaeger, E. F. [XCEL Engineering Inc., Oak Ridge, Tennessee 37830 (United States)
A feasibility study of low-order harmonics expansion applied to loading pattern search
Despite significant progress in core loading pattern search methods over years, there still remains the issue of large computing workload and the need for improving the speed of evaluating loading pattern candidates during the search process. This paper focuses on improving the computing speed for loading pattern evaluation, rather than the method of searching for the patterns. A low order harmonics expansion method for flux distribution representation is proposed for fast LP evaluation application. The novel feature of the method is the separation of the short range local perturbation effect from the long range global tilt effect. The latter effect can be captured by low order harmonics expansion. Demonstration examples are presented to show that even for extremely large perturbations induced by fuel shuffling the proposed method can accurately calculate the flux distribution for the LP with very minimal computation. (authors)
Shaohong, Z.; Dong, L.; Tao, W. [Shanghai Jiao Tong Univ., 1954 Hua Shan Road, Shanghai, 200030 (China); Chao, Y. A. [Westinghouse Electric Company, P. O. Box 355, Pittsburgh, PA 15230-0355 (United States)
Two particle correlation measurements with respect to higher harmonic event planes at PHENIX
Measurements of two particle azimuthal correlations in relativistic heavy ion collisions provide information of the possible interplay between hard-scattered partons and the hot-dense medium. Toward an understanding of parton-medium coupling, it is indispensable to obtain correlations where contributions from higher harmonic flow($v_n$) are rejected. It is also important to produce correlation measurements where the trigger particle is selected relative to second and third order event planes. This enables us to explore path-length dependence of parton energy loss and the influence of the medium on the jets. We present the latest PHENIX results of correlations in which contributions from higher harmonic flow have been subtracted, as well as second and third order event plane-dependent correlations in Au+Au collisions at $\\sqrt{s_{NN}}=200$ GeV.
Takahito Todoroki for the PHENIX Collaboration
Investigations of Low and Moderate Harmonic Fast Wave Physics on CDX-U
Third harmonic hydrogen cyclotron fast wave heating studies are planned in the near term on CDX-U to investigate the potential for bulk ion heating. In preparation for these studies, the available radio-frequency power in CDX-U has been increased to 0.5 MW. The operating frequency of the CDX-U radio-frequency transmitter was lowered to operate in the range of 8-10 MHz, providing access to the ion harmonic range 2* {approx} 4* in hydrogen. A similar regime is accessible for the 30 MHz radio-frequency system on the National Spherical Torus Experiment (NSTX), at 0.6 Tesla in hydrogen. Preliminary computational studies over the plasma regimes of interest for NSTX and CDX-U indicate the possibility of strong localized absorption on bulk ion species.
J. Spaleta; R. Majeski; C.K. Phillips; R.J. Dumont; R. Kaita; V. Soukhanovskii; L. Zakharov
Multiple layer optical memory system using second-harmonic-generation readout
A novel optical read and write information storage system is described which comprises a radiation source such as a laser for writing and illumination, the radiation source being capable of radiating a preselected first frequency; a storage medium including at least one layer of material for receiving radiation from the radiation source and capable of being surface modified in response to said radiation source when operated in a writing mode and capable of generating a pattern of radiation of the second harmonic of the preselected frequency when illuminated by the radiation source at the preselected frequency corresponding to the surface modifications on the storage medium; and a detector to receive the pattern of second harmonic frequency generated.
Boyd, Gary T. (Woodbury, MN); Shen, Yuen-Ron (Berkeley, CA)
Harmonizing Global Metrics for Data Center Energy Efficiency (February 2, 2010)
Harmonizing Global Metrics for Data Center Energy Efficiency Harmonizing Global Metrics for Data Center Energy Efficiency The United States of America, European Union and Japan Reach Agreement on Guiding Principles for Data Center Energy Efficiency Metrics February 2, 2010 As business demands and energy costs for data centers rise, owners and operators have focused on the energy efficiency of the data center as a whole, frequently using energy efficiency metrics. However, the metrics are not always applied clearly and consistently at a global level. To address these inconsistencies, a group of global leaders met on February 2, 2010 to agree on data center energy efficiency measurements, metrics, and reporting conventions. Organizations represented were the U.S. Department of Energy's Save Now and Federal Energy Management Programs,
High harmonic attosecond pulse train amplification in a free electron laser
It is shown using three-dimensional simulations that the temporal structure of an attosecond pulse train, such as that generated via high harmonic generation in noble gases, may be retained in a free electron laser amplifier through to saturation using a mode-locked optical klystron configuration. At wavelengths of {approx}12 nm, a train of attosecond pulses of widths {approx}300 as with peak powers in excess of 1 GW are predicted.
McNeil, B.W.; Sheehy, B.; Thompson, N.R.; Dunning, D.J.
Life Cycle Greenhouse Gas Emissions of Coal-Fired Electricity Generation: Systematic Review and Harmonization
This systematic review and harmonization of life cycle assessments (LCAs) of utility-scale coal-fired electricity generation systems focuses on reducing variability and clarifying central tendencies in estimates of life cycle greenhouse gas (GHG) emissions. Screening 270 references for quality LCA methods, transparency, and completeness yielded 53 that reported 164 estimates of life cycle GHG emissions. These estimates for subcritical pulverized, integrated gasification combined cycle, fluidized bed, and supercritical pulverized coal combustion technologies vary from 675 to 1,689 grams CO{sub 2}-equivalent per kilowatt-hour (g CO{sub 2}-eq/kWh) (interquartile range [IQR]= 890-1,130 g CO{sub 2}-eq/kWh; median = 1,001) leading to confusion over reasonable estimates of life cycle GHG emissions from coal-fired electricity generation. By adjusting published estimates to common gross system boundaries and consistent values for key operational input parameters (most importantly, combustion carbon dioxide emission factor [CEF]), the meta-analytical process called harmonization clarifies the existing literature in ways useful for decision makers and analysts by significantly reducing the variability of estimates ({approx}53% in IQR magnitude) while maintaining a nearly constant central tendency ({approx}2.2% in median). Life cycle GHG emissions of a specific power plant depend on many factors and can differ from the generic estimates generated by the harmonization approach, but the tightness of distribution of harmonized estimates across several key coal combustion technologies implies, for some purposes, first-order estimates of life cycle GHG emissions could be based on knowledge of the technology type, coal mine emissions, thermal efficiency, and CEF alone without requiring full LCAs. Areas where new research is necessary to ensure accuracy are also discussed.
Whitaker, M.; Heath, G. A.; O'Donoughue, P.; Vorum, M.
Quasi-phase matching and quantum control of high harmonic generation in waveguides using counterpropagating beams
All-optical quasi-phase matching (QPM) uses a train of counterpropagating pulses to enhance high-order harmonic generation (HHG) in a hollow waveguide. A pump pulse enters one end of the waveguide, and causes HHG in the waveguide. The counterpropagation pulses enter the other end of the waveguide and interact with the pump pulses to cause QPM within the waveguide, enhancing the HHG.
Zhang, Xiaoshi (Superior, CO); Lytle, Amy L. (Boulder, CO); Cohen, Oren (Boulder, CO); Kapteyn, Henry C. (Boulder, CO); Murnane, Margaret M. (Boulder, CO)
Three-dimensional N=4 supersymmetry in harmonic N=3 superspace
We consider the map of three-dimensional N=4 superfields to N=3 harmonic superspace. The left and right representations of the N=4 superconformal group are constructed on N=3 analytic superfields. These representations are convenient for the description of N=4 superconformal couplings of the Abelian gauge superfields with hypermultiplets. We analyze the N=4 invariance in the non-Abelian N=3 Yang-Mills theory.
B. M. Zupnik
Second harmonic nano-particles for femtosecond coherent control on the nanoscale
We provide a complete toolkit for coherent control experiments on the nano-scale. By exploiting the second harmonic emission from single (150 nm) nonlinear nano-particles, we show that ultrafast femtosecond laser pulses can be compressed and controlled in time with unprecedented spatial accuracy. The method is tested on various nano-particles of different sizes, shapes and materials, both dielectric BaTiO3, Fe(IO3)3) and metallic (Au) thus demonstrating its robustness and versatility.
Accanto, Nicol�; Piatkowski, Lukasz; Castro-Lopez, Marta; Pastorelli, Francesco; Brinks, Daan; van Hulst, Niek F
A frequency scanning method for the identification of harmonic instabilities in HVDC systems
A Frequency Scanning Method is introduced in the paper to obtain a more accurate frequency characteristic for identifying harmonic instability in HVdc systems. An example of the application is used to identify the resonance frequencies in the CIGRE benchmark model. The paper shows that the Benchmark model is not tuned to the resonance frequency that it was designed for. Using the scanning method, the resonance frequency of the benchmark model may be shifted to demonstrate a simulation of core-saturation type instability.
Jiang, X.; Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada). Dept. of Electrical and Computer Engineering
Doubling�Adding Method for Delta-Four-Stream Spherical Harmonic Expansion Approximation in Radiative Transfer Parameterization
Though the single-layer solutions have been found for the ?-four-stream spherical harmonic expansion method (SHM) in radiative transfer, there is lack of a corresponding doubling�adding method (4SDA), which enables the calculation of radiative ...
Feng Zhang; Jiangnan Li
Electron Dynamics of Silicon Surface States: Second-Harmonic Hole Burning on Si(111)7x7
States: Second-Harmonic Hole Burning on Si(111) 7� 7 John A.transient spectral hole burning. Spectral holes induced by atransient spectral hole burning, i.e. , the surface-speci?c
McGuire, John A.; Raschke, Markus B.; Shen, Yuen-Ron
Methods, systems and apparatus for approximation of peak summed fundamental and third harmonic voltages in a multi-phase machine
Methods, system and apparatus are provided for quickly approximating a peak summed magnitude (A) of a phase voltage (Vph) waveform in a multi-phase system that implements third harmonic injection.
Ransom, Ray M. (Big Bear City, CA); Gallegos-Lopez, Gabriel (Torrance, CA); Kinoshita, Michael H. (Redondo Beach, CA)
Lattice Monte Carlo calculations for unitary fermions in a harmonic trap
We present a lattice Monte Carlo approach developed for studying large numbers of strongly interacting nonrelativistic fermions and apply it to a dilute gas of unitary fermions confined to a harmonic trap. In place of importance sampling, our approach makes use of high statistics, an improved action, and recently proposed statistical techniques. We show how improvement of the lattice action can remove discretization and finite volume errors systematically. For N=3 unitary fermions in a box, our errors in the energy scale as the inverse lattice volume, and we reproduce a previous high-precision benchmark calculation to within our 0.3% uncertainty; as additional benchmarks we reproduce precision calculations of N=3,...,6 unitary fermions in a harmonic trap to within our {approx}1% uncertainty. We then use this action to determine the ground-state energies of up to 70 unpolarized fermions trapped in a harmonic potential on a lattice as large as 64{sup 3}x72. In contrast to variational calculations, we find evidence for persistent deviations from the thermodynamic limit for the range of N considered.
Endres, Michael G.; Kaplan, David B.; Lee, Jong-Wan; Nicholson, Amy N. [Physics Department, Columbia University, New York, New York 10027 (United States); Theoretical Research Division, RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195-1550 (United States)
The Significance to Quantum Computing of the Classical Harmonic Nature of Energy Eigenstates
Since a pure quantum system is incapable of faithfully simulating the solutions of the Schroedinger equation that actually pertains to itself, it is proposed that quantum computing technology (as opposed to cryptographic technology) not be based on pure quantum systems such as qubits but instead on physical systems which by their nature faithfully simulate the solutions of Schroedinger equations. Every Schroedinger equation is within a unitary transformation of being a set of mutually independent classical simple harmonic oscillator equations. Thus classical simple harmonic oscillators, or "chobits", are the mathematically fundamental building blocks for all Schroedinger equations. In addition, classical harmonic oscillators are, as a practical matter, far easier to deal with than any pure quantum system -- e.g., their phases and absolute amplitudes are readily physically accessible, they have little predilection for environmental decoherence, and they abound as cavity electromagnetic standing-wave modes. We study in mathematical detail the use of chobits to compute discrete quantum Fourier transforms, including gates, chobit counts, and chobit operation counts. The results suggest that thirty chobits and under a thousand chobit phase operations could generate discrete quantum Fourier transforms of a billion terms. Chobits can be technologically realized as semiconductor dynatron-type electronic oscillator circuits, which ought to be amenable to very considerable miniaturization.
Steven Kenneth Kauffmann
Power Quality Mitigation Technology Demonstration at Industrial Customer Sites: Industrial and Utility Harmonic Mitigation Guideline s and Case Studies
However the restructuring of the electric power industry shakes out, the commercial/industrial customer's need for quality power will increase; and customer service will remain a key to retaining current accounts and attracting new customers. The need for demonstrating new harmonics mitigation technologies will thus be an important factor for the wire side of the business as well as for energy service companies. This report provides guidelines for implementing harmonics mitigation demonstration projects ...
Filamentation-induced third-harmonic generation in air via plasma-enhanced third-order susceptibility
We study, both experimentally and theoretically, the underlying physics of third-harmonic generation in air by a filamented infrared femtosecond laser pulse propagating through a thin plasma channel. It is shown that the recently observed more than two-order-of-magnitude increase of the efficiency of third-harmonic generation occurs due to the plasma-enhanced third-order susceptibility. An estimate of the effective value of this susceptibility is given.
Suntsov, S.; Abdollahpour, D.; Tzortzakis, S. [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 71110, Heraklion (Greece); Papazoglou, D. G. [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 71110, Heraklion (Greece); Materials Science and Technology Department, University of Crete, 71003, Heraklion (Greece)
Opportunities for regional harmonization of appliance standards and l abeling program
The South Asian Regional Initiative for Energy (SARI/Energy) calls for a series of activities to promote Energy Efficiency Standards and Labeling (EES&L) of end use appliances in the region. In pursuit of this goal, the project supports several seminars and meetings that bring together policymakers and stakeholders from throughout the region. The purpose of these gatherings is to encourage a dialogue among participants as to the benefits and barriers associated with EES&L programs. In addition, it is the role of the program organizers to provide participants with the technical details necessary to make progress towards effective efficiency programs. One component of the initiative is to encourage the harmonization (alignment) of existing program components, and the pursuit of new programs coordinated at the regional level. In support of this goal, the report provides information aimed at motivating and enabling cooperative activities which will provide concrete benefits to programs in each country, whether well developed, or still in the initial planning stage. It should be emphasized that the underlying objective of the harmonization component of the SARI/Energy project is to increase the potential for success of EES&L programs of all countries involved, and to reduce burdens on manufacturers, exporters and importers in each country. Harmonization ''for it's own sake'' is not desirable, nor is it suggested that policymakers should bring their programs in line with international norms if doing so would present a disadvantage to their own efficiency programs, or to commercial interests within their country. If there is no such disadvantage, however, the program encourages alignment of policies and provides a forum at which this alignment can be pursued. The report covers several main topics, with varying emphasis. First, a general discussion of the motivation for an explicit policy of regional harmonization is given. Next, the current status of existing programs in the region are discussed in some detail. The section that follows covers the harmonization of efficiency test procedures. Special attention is given to this component of an EES&L program because it is the most critical element in terms of harmonization--having incompatible test procedures between trade partners can greatly impact the effectiveness of a program, and it can also unduly impact trade. Currently, policymakers in India and Sri Lanka are collaborating with the goal of aligning refrigerator test procedures used in their respective programs. For this reason, the section on test procedures of refrigerators goes into a significant amount of technical detail, in order to provide the clearest possible articulation of issues to be resolved in bringing the procedures into alignment. Following the discussion of test procedures, the report contains a section each on harmonization of efficiency rating levels, development of label designs, and enforcement issues. The report is organized such that the sections covering current programs and test procedures are subdivided by target appliance. These sections are further divided by country, where applicable. Each section is concluded with recommendations.
McNeil, Michael A.
Observation of Orbital Ordering and Jahn-Teller Distortions Supporting the Wigner-crystal Model in Highly Dopes Bi{1-x}Ca{x}MnO{3}
We report on the experimental characterization of orbital ordering and the associated lattice distortions in highly doped Bi{sub 1-x}Ca{sub x}MnO{sub 3}. Resonant x-ray diffraction was used at the Mn L-edge for the direct observation of the ordered localized states, and at the Mn K-edge for the sensitivity to the distortions of the manganese-oxygen octahedra. The orbital ordering on Mn atoms was directly observed at x=0.69; the analysis and the numerical simulations of the K-edge spectra allow us to characterize the pattern of the distorted octahedra at x = 4/5. These observations support the Wigner-crystal-type model at both dopings; the bi-stripe model is ruled out at x = 0.69.
Grenier,S.; Kiryukhin, V.; Cheong, S.; Kim, B.; Hill, J.; Thomas, K.; Tonnerre, J.; Joly, Y.; Staub, U.; Scagnoli, V.
Stability of Jahn-Teller distortion in LaMnO{sub 3} under pressure: An x-ray absorption study
The local environment of manganese atoms in LaMnO{sub 3} under pressure up to 15.3 GPa has been studied by x-ray absorption spectroscopy. For pressures below 8 GPa, no change is detected within the MnO{sub 6} octahedra. Above this pressure a continuous reduction of the long Mn-O distance takes place, however, the octahedral distortion persists over the whole pressure range. At 15.3 GPa the average Jahn-Teller splitting of the distances is reduced by about one-third, indicating that a total removal of the local Jahn-Teller distortion would occur only for pressures around 30 GPa, where metallization is reported to take place. A hysteresis in the long distance reduction is observed down to ambient pressure, suggesting the coexistence of MnO{sub 6} distorted and undistorted units.
Ramos, Aline Y.; Tolentino, Helio C. N.; Souza-Neto, Narcizo M.; Itie, Jean-Paul; Morales, Liliana; Caneiro, Alberto [Institut Neel, UPR 2940-CNRS, 25 av. des Martyrs, Boite Postale 166, 38042 Grenoble, France and Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo (Brazil); Laboratorio Nacional de Luz Sincrotron-LNLS, P.O. Box 6192, 13084-971, Campinas, Sao Paulo, Brazil and Departamento de Fisica dos Materiais e Mecanica, DFMT-IF-USP, Sao Paulo, SP (Brazil); Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex (France); Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica and Universidad Nacional de Cuyo, 8400 S.C. de Bariloche (Argentina)
Life Cycle Greenhouse Gas Emissions of Nuclear Electricity Generation: Systematic Review and Harmonization
A systematic review and harmonization of life cycle assessment (LCA) literature of nuclear electricity generation technologies was performed to determine causes of and, where possible, reduce variability in estimates of life cycle greenhouse gas (GHG) emissions to clarify the state of knowledge and inform decision making. LCA literature indicates that life cycle GHG emissions from nuclear power are a fraction of traditional fossil sources, but the conditions and assumptions under which nuclear power are deployed can have a significant impact on the magnitude of life cycle GHG emissions relative to renewable technologies. Screening 274 references yielded 27 that reported 99 independent estimates of life cycle GHG emissions from light water reactors (LWRs). The published median, interquartile range (IQR), and range for the pool of LWR life cycle GHG emission estimates were 13, 23, and 220 grams of carbon dioxide equivalent per kilowatt-hour (g CO{sub 2}-eq/kWh), respectively. After harmonizing methods to use consistent gross system boundaries and values for several important system parameters, the same statistics were 12, 17, and 110 g CO{sub 2}-eq/kWh, respectively. Harmonization (especially of performance characteristics) clarifies the estimation of central tendency and variability. To explain the remaining variability, several additional, highly influential consequential factors were examined using other methods. These factors included the primary source energy mix, uranium ore grade, and the selected LCA method. For example, a scenario analysis of future global nuclear development examined the effects of a decreasing global uranium market-average ore grade on life cycle GHG emissions. Depending on conditions, median life cycle GHG emissions could be 9 to 110 g CO{sub 2}-eq/kWh by 2050.
Warner, E. S.; Heath, G. A.
Study of second harmonic generation by high power laser beam in magneto plasma
This paper examines the problem of nonlinear generation of second harmonic of a high power laser pulse propagating in magnetized plasma. The propagation of strong laser beam is proposed in the direction perpendicular to a relatively weak static magnetic field. The laser pulse is taken to be linearly polarized, with the orientation of its electric field that corresponds to an ordinary electromagnetic wave. Besides the standard ponderomotive nonlinearity, the appropriate wave equation also contains the nonlinearity that arises from the relativistic electron jitter velocities. During its propagation, the laser beam gets filamented on account of relativistic and pondermotive nonlinearities present in the plasma. The generated plasma wave gets coupled into the filamentary structures of the pump beam. Due to the expected presence of the beam filamentation, the work has been carried out by considering modified paraxial approximation (i.e., beyond the standard paraxial approximation of a very broad beam). It is found that the power of the plasma wave is significantly affected by the magnetic field strength in the presence of both relativistic and pondermotive nonlinearities. It is investigated that the second harmonic generation is also considerably modified by altering the strength of magnetic field. To see the effect of static magnetic field on the harmonic generation, a key parameter, i.e., the ratio of the cyclotron frequency {omega}{sub c}=eB{sub 0}/mc over the laser frequency {omega}{sub 0} has been used, where c is the velocity of light, m and e are the mass and charge of the electron and B{sub 0} is the externally applied magnetic field.
Sharma, Prerana [Ujjain Engineering College, Ujjain, Madhya Pradesh 465010 (India); Sharma, R. P. [Centre for Energy Studies, Indian Institute of Technology, New Delhi 110016 (India)
iHarmonizer: improving the disk efficiency of I/O-intensive multithreaded codes
Challenged by serious power and thermal constraints, and limited by available instruction-level parallelism, processor designs have evolved to multi-core architectures. These architectures, many augmented with native simultaneous multithreading, are driving software developers to use multithreaded programs to exploit thread-level parallelism. While multithreading is well-known to introduce concerns of data dependency and CPU load balance, less known is that the uncertainty of relative progress of thread execution can cause patterns of I/O requests, issued by different threads, to be effectively random and so significantly degrade hard-disk efficiency. This effect can severely offset the performance gains from parallel execution, especially for I/O-intensive programs. Retaining the benefits of multithreading while not reducing I/O efficiency is an urgent and challenging problem. We propose a user-level scheme, iHarmonizer, to streamline the servicing of I/O requests from multiple threads in OpenMP programs. Specifically, we use the compiler to insert code into OpenMP programs so that data usage can be transmitted at run time to a supporting run-time library; this library in turn prefetches data in a disk-friendly way and coordinates threads execution according to the availability of their requested data. Transparently to the programmer, iHarmonizer makes a multithreaded program I/O efficient while maintaining the benefits of parallelism. Our experiments show that iHarmonizer can significantly speed up the execution of a representative set of I/O-intensive scientific benchmarks.
Davis, Marion Kei [Los Alamos National Laboratory; Wang, Yizhe [WAYNE STATE UNIV.; Jiang, Song [WAYNE STATE UNIV.
Method and apparatus for reducing the harmonic currents in alternating-current distribution networks
An improved apparatus and method reduce the harmonic content of AC line and neutral line currents in polyphase AC source distribution networks. The apparatus and method employ a polyphase Zig-Zag transformer connected between the AC source distribution network and a load. The apparatus and method also employs a mechanism for increasing the source neutral impedance of the AC source distribution network. This mechanism can consist of a choke installed in the neutral line between the AC source and the Zig-Zag transformer.
Beverly, Leon H. (Lockport, IL); Hance, Richard D. (Elburn, IL); Kristalinski, Alexandr L. (Naperville, IL); Visser, Age T. (Geneva, IL)
An improved apparatus and method reduce the harmonic content of AC line and neutral line currents in polyphase AC source distribution networks. The apparatus and method employ a polyphase Zig-Zag transformer connected between the AC source distribution network and a load. The apparatus and method also employs a mechanism for increasing the source neutral impedance of the AC source distribution network. This mechanism can consist of a choke installed in the neutral line between the AC source and the Zig-Zag transformer. 23 figs.
Beverly, L.H.; Hance, R.D.; Kristalinski, A.L.; Visser, A.T.
Program on Technology Innovation: Evaluation of a Commercially Available Harmonic Filter
Emissions tests were conducted to analyze common and differential noise, harmonics, and current draw characteristics in the electrical systems of a typical household. A test setup was constructed to simulate the circuits of this typical household in order to determine how the STETZERiZER� Filters might affect the electric currents and voltages these circuits. Testing was performed in a frequency range of 3 kHz - 150 kHz to measure the effect of these filters on power draw and power quality, as ...
Interbasis expansions for the isotropic 3D harmonic oscillator and bivariate Krawtchouk polynomials
An explicit expression for the general bivariate Krawtchouk polynomials is obtained in terms of the standard Krawtchouk and dual Hahn polynomials. The bivariate Krawtchouk polynomials occur as matrix elements of the unitary reducible representations of SO(3) on the energy eigenspaces of the 3-dimensional isotropic harmonic oscillator and the explicit formula is obtained from the decomposition of these representations into their irreducible components. The decomposition entails expanding the Cartesian basis states in the spherical bases that span irreducible SO(3) representations. The overlap coefficients are obtained from the Clebsch-Gordan problem for the su(1,1) Lie algebra.
Vincent X. Genest; Luc Vinet; Alexei Zhedanov
Chaos, ergodic convergence, and fractal instability for a thermostated canonical harmonic oscillator
The authors thermostat a qp harmonic oscillator using the two additional control variables {zeta} and {xi} to simulate Gibbs' canonical distribution. In contrast to the motion of purely Hamiltonian systems, the thermostated oscillator motion is completely ergodic, covering the full four-dimensional {l_brace}q,p,{zeta},{xi}{r_brace} phase space. The local Lyapunov spectrum (instantaneous growth rates of a comoving corotating phase-space hypersphere) exhibits singularities like those found earlier for Hamiltonian chaos, reinforcing the notion that chaos requires kinetic -- as opposed to statistical -- study, both at and away from equilibrium. The exponent singularities appear to have a fractal character.
Hoover, Wm. G.; Hoover, Carol G.; Isbister, Dennis J.
Common Information Model (CIM)-MultiSpeak Harmonization 2nd Edition
The CIM�MultiSpeak harmonization effort sought to identify the degree of correlation that exists between the International Electrotechnical Commission (IEC) Common Information Model (CIM), which is based on IEC standards 61968, 61970, and 62325, and the MultiSpeak v4.1.5 standard for electric system interoperability. The initial effort focused on mapping attributes from the IEC 61968-9 profiles to equivalent profiles that were created for MultiSpeak v4.1.5. A proof-of-concept interoperability ...
Condensation of two-dimensional harmonically confined bosons with Bessel-type interactions
We study the ground-state configurations of few interacting bosons confined in two dimensions by anisotropic harmonic potentials. By means of variational calculations, including correlation effects, we show that the arrangement of bosons strongly depends on the strength of the repulsive interaction and the anisotropy of the confinement. We compute the condensate fraction of the system and found that by increasing the anisotropy of the potential a weaker interaction suffices to destroy the condensate and favors the emergence of a crystal-like structure.
Mese, A. I.; Aktas, S.; Okan, S. E. [Department of Physics, Trakya University, 22030 Edirne (Turkey); Capuzzi, P. [Instituto de Fisica de Buenos Aires, Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Departamento de Fisica, FCEyN, Universidad de Buenos Aires, Buenos Aires (Argentina); Akdeniz, Z. [Piri Reis University, 34940 Tuzla, Istanbul (Turkey)
Unified Representation of Quantum Mechanics on One-dimensional Harmonic Oscillator
A quantum state corresponds to a specific wave function. We adopt a new mathematical method [1] to improve Dirac's ladder operator method. A set of orthonormal wave functions will be used to associate the operator with the square matrix corresponding to it. These allow us to determine the matrix elements by using the operator relations without having to know the specific wave functions. As a result, we can get the direct results of matrix mechanics and wave mechanics on one-dimensional Harmonic oscillator and their descriptions will be also unified.
Yongqin Wang
Calculation of HVDC-converter harmonics in frequency domain with regard to asymmetries and comparison with time domain simulations
In order to study the effects of large HVDC converters to the feeding ac networks, it is of importance to explain and to calculate harmonic phenomena which are a result of converter operation. During commissioning of real HVDC converters it could be seen, that harmonics resulting from unsymmetries in the system voltages or from unsymmetries in converter operation led to significant difficulties concerning the system design. For this reason, not only the effects of characteristic but also the effects of noncharacteristic converter harmonics must be taken into account. The aim is to describe the steady state harmonic behavior of the converter. The harmonic spectra are not determined by time domain analysis but instead the solution is found by frequency domain calculations. This can result in reduced calculation time in comparison to conventional fourier analysis of the time functions. The converter is interpreted as an amplitude modulator with voltage and current converter functions which describe the coupling of the dc circuit and the ac network through the converter. To verify the theory, comparison of frequency domain with time domain calculations were carried out.
Rittiger, J. [Siemens AG, Erlangen (Germany); Kulicke, B. [Technische Univ. Berlin (Germany)
The phase diagram of ice Ih, II, and III: a quasi-harmonic study
The phase diagram of ice Ih, II, and III is studied by a quasi-harmonic approximation. The results of this approach are compared to phase diagrams previously derived by thermodynamic integration using path integral and classical simulations, as well as to experimental data. The studied models are based on both flexible (q-TIP4P/F) and rigid (TIP4P/2005, TIP4PQ/2005) descriptions of the water molecule. Many aspects of the simulated phase diagrams are reasonably reproduced by the quasi-harmonic approximation. Advantages of this simple approach are that it is free from the statistical errors inherent to computer simulations, both classical and quantum limits are easily accessible, and the error of the approximation is expected to decrease in the zero temperature limit. We find that the calculated phase diagram of ice Ih, II, and III depends strongly on the hydrogen disorder of ice III, at least for cell sizes typically used in phase coexistence simulations. Either ice II (in the classical limit) or ice III (in t...
Ramirez, R; Herrero, C P; 10.1063/1.4757064
A Proof-of-Principle Echo-enabled Harmonic Generation Free Electron Laser Experiment at SLAC
With the advent of X-ray Free Electron Lasers (FELs), new methods have been developed to extend capabilities at short wavelengths beyond Self-Amplified Spontaneous Emission (SASE). In particular, seeding of a FEL allows for temporal control of the radiation pulse and increases the peak brightness by orders of magnitude. Most recently, Gennady Stupakov and colleagues at SLAC proposed a new technique: Echo-Enabled Harmonic Generation (EEHG). Here a laser microbunches the beam in an undulator and the beam is sheared in a chicane. This process is repeated with a second laser, undulator and chicane. The interplay between these allows a seeding of the X-ray laser up to the 100th harmonic of the first laser. After introducing the physics of FELs and the EEHG seeding technique, we describe contributions to the experimental effort. We will present detailed studies of the experiment including the choice of parameters and their optimization, the emittance effect, spontaneous emission in the undulators, the second laser phase effect, and measurements of the jitter between RF stations. Finally, the status and preliminary results of the Echo-7 experiment will be outlined.
Pernet, Pierre-Louis; /Ecole Polytechnique, Lausanne /SLAC
Inter- and Intra-Observer Variability in Prostate Definition With Tissue Harmonic and Brightness Mode Imaging
Purpose: The objective of this study was to compare the relative utility of tissue harmonic (H) and brightness (B) transrectal ultrasound (TRUS) images of the prostate by studying interobserver and intraobserver variation in prostate delineation. Methods and Materials: Ten patients with early-stage disease were randomly selected. TRUS images of prostates were acquired using B and H modes. The prostates on all images were contoured by an experienced radiation oncologist (RO) and five equally trained observers. The observers were blinded to information regarding patient and imaging mode. The volumes of prostate glands and areas of midgland slices were calculated. Volumes contoured were compared among the observers and between observer group and RO. Contours on one patient were repeated five times by four observers to evaluate the intraobserver variability. Results: A one-sample Student t-test showed the volumes outlined by five observers are in agreement (p > 0.05) with the RO. Paired Student t-test showed prostate volumes (p = 0.008) and midgland areas (p = 0.006) with H mode were significantly smaller than that with B mode. Two-factor analysis of variances showed significant interobserver variability (p =}35 cc), B mode provided more consistent estimates. Conclusions: H mode provided superior inter- and intraobserver agreement in prostate volume definition for small to medium prostates. In large glands, H mode does not exhibit any additional advantage. Although harmonic imaging has not proven advantageous for all cases, its utilization seems to be judicious for small prostates.
Sandhu, Gurpreet Kaur, E-mail: email@example.com [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Dunscombe, Peter [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada); Meyer, Tyler [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Pavamani, Simon [Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada); Department of Radiation Oncology, Christian Medical College, Vellore (India); Khan, Rao [Department of Medical Physics, Tom Baker Cancer Centre, Calgary, Alberta (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, Alberta (Canada); Department of Oncology, Faculty of Medicine, University of Calgary, Calgary, Alberta (Canada)
$?(\\hat{x},\\hat{p})-$deformation of the harmonic oscillator in a $2D-$phase space
This work addresses a ${\\theta}(\\hat{x},\\hat{p})-$deformation of the harmonic oscillator in a $2D-$phase space. Specifically, it concerns a quantum mechanics of the harmonic oscillator based on a noncanonical commutation relation depending on the phase space coordinates. A reformulation of this deformation is considered in terms of a $q-$deformation allowing to easily deduce the energy spectrum of the induced deformed harmonic oscillator. Then, it is proved that the deformed position and momentum operators admit a one-parameter family of self-adjoint extensions. These operators engender new families of deformed Hermite polynomials generalizing usual $q-$ Hermite polynomials. Relevant matrix elements are computed. Finally, a $su(2)-$algebra representation of the considered deformation is investigated and discussed.
M. N. Hounkonnou; D. Ousmane Samary; E. Baloitcha; S. Arjika
Forecasts for CMB ?- and i-type spectral distortion constraints on the primordial power spectrum on scales 8 < k < 10^4 Mpc^-1 with the future Pixie-like experiments
Silk damping at redshifts 1.5 x 10^4 < z < 2 x 10^6 erases CMB anisotropies on scales corresponding to the comoving wavenumbers 8 < k < 10^4 Mpc^-1 (10^5 < \\ell < 10^8). This dissipated energy is gained by the CMB monopole, creating distortions from a blackbody in the CMB spectrum of the \\mu-type and the i-type. We study, using Fisher matrices, the constraints we can get from measurements of these spectral distortions on the primordial power spectrum from future experiments such as Pixie, and how these constraints change as we change the frequency resolution and the sensitivity of the experiment. We show that the additional information in the shape of the $i$-type distortions, in combination with the \\mu-type distortions, allows us to break the degeneracy between the amplitude and the spectral index of the power spectrum on these scales and leads to much tighter constraints. We quantify the information contained in both the \\mu-type distortions and the i-type distortions taking into account the partial degeneracy with the y-type distortions and the temperature of the blackbody part of the CMB. We also calculate the constraints possible on the primordial power spectrum when the spectral distortion information is combined with the CMB anisotropies measured by the WMAP, SPT, ACT and Planck experiments.
Rishi Khatri; Rashid A. Sunyaev
Life Cycle Greenhouse Gas Emissions of Trough and Tower Concentrating Solar Power Electricity Generation: Systematic Review and Harmonization
In reviewing life cycle assessment (LCA) literature of utility-scale concentrating solar power (CSP) systems, this analysis focuses on reducing variability and clarifying the central tendency of published estimates of life cycle greenhouse gas (GHG) emissions through a meta-analytical process called harmonization. From 125 references reviewed, 10 produced 36 independent GHG emissions estimates passing screens for quality and relevance: 19 for parabolic trough (trough) technology and 17 for power tower (tower) technology. The interquartile range (IQR) of published estimates for troughs and towers were 83 and 20 grams of carbon dioxide equivalent per kilowatt-hour (g CO2-eq/kWh),1 respectively; median estimates were 26 and 38 g CO2-eq/kWh for trough and tower, respectively. Two levels of harmonization were applied. Light harmonization reduced variability in published estimates by using consistent values for key parameters pertaining to plant design and performance. The IQR and median were reduced by 87% and 17%, respectively, for troughs. For towers, the IQR and median decreased by 33% and 38%, respectively. Next, five trough LCAs reporting detailed life cycle inventories were identified. The variability and central tendency of their estimates are reduced by 91% and 81%, respectively, after light harmonization. By harmonizing these five estimates to consistent values for global warming intensities of materials and expanding system boundaries to consistently include electricity and auxiliary natural gas combustion, variability is reduced by an additional 32% while central tendency increases by 8%. These harmonized values provide useful starting points for policy makers in evaluating life cycle GHG emissions from CSP projects without the requirement to conduct a full LCA for each new project.
Burkhardt, J. J.; Heath, G.; Cohen, E.
Universal and deterministic manipulation of the quantum state of harmonic oscillators: a route to unitary gates for Fock State qubits
We present a simple quantum circuit that allows for the universal and deterministic manipulation of the quantum state of confined harmonic oscillators. The scheme is based on the selective interactions of the referred oscillator with an auxiliary three-level system and a classical external driving source, and enables any unitary operations on Fock states, two-by-two. One circuit is equivalent to a single qubit unitary logical gate on Fock states qubits. Sequences of similar protocols allow for complete, deterministic and state-independent manipulation of the harmonic oscillator quantum state.
Marcelo Franca Santos
Analytical modeling of pulse-pileup distortion using the true pulse shape; applications to Fermi-GBM
Pulse-pileup affects most photon counting systems and occurs when photon detections occur faster than the detector's registration and recovery time. At high input rates, shaped pulses interfere and the source spectrum, as well as intensity information, get distorted. For instruments using bipolar pulse shaping there are two aspects to consider: `peak' and `tail' pileup effects, which raise and lower the measured energy, respectively. Peak effects have been extensively modeled in the past. Tail effects have garnered less attention due to the increased complexity: bipolar tails mean the tail pulse-height measurement depends on events in more than one time interval. We leverage previous work to derive an accurate, semi-analytical prediction for peak and tail pileup, up to high orders. We use the true pulse shape from the detectors of the Fermi Gamma-ray Burst Monitor. The measured spectrum is calculated by writing exposure time as a state-space expansion of overlapping pileup states and is valid up to very high rates. This expansion models losses due to fixed and extendable deadtime by averaging overlap configurations. Additionally, the model correctly predicts energy-dependent losses due to tail subtraction (sub-threshold) effects. We discuss pileup losses in terms of the true rate of photon detections versus the recorded count rate.
Vandiver Chaplin; Narayana Bhat; Michael Briggs; Valerie Connaughton
Clustering in the 1.2 Jy IRAS Galaxy Redshift Survey II: Redshift Distortions and ?(r_p,?)
We examine the effect of redshift space distortions on the galaxy two-point correlation function $\\xi(r_p,\\pi)$ as a function of separations parallel ($r_p$) and perpendicular ($\\pi$) to the line of sight. We find that the relative velocity dispersion of pairs of IRAS galaxies is $\\sigma(r)= 317^{+40}_{-49}$ \\kms at $r=1 \\mpc$, consistent with previous estimates derived from optically selected galaxy catalogues. Unfortunately, the use of this result to estimate $\\Omega$ via the Cosmic Virial Theorem is thwarted by large systematic uncertainties. We also fit for the mean relative streaming velocity of pairs, $v_{12}(r)$, which describes the growth of fluctuations on both linear and nonlinear scales. We find that $v_{12}(r) = 167^{+99}_{-67}$ \\kms at $r=4$\\mpc, so that on average, approximately half the Hubble expansion velocity of pairs at this separation is canceled by infall. At $r=10$\\mpc, the amplitude of the streaming is lower and $v_{12}(r) = 109^{+64}_{-47} \\kms$. Linear perturbation theory then implies that $\\Omega^{0.6}/b =0.45^{+0.27}_{-0.18}$ on scales $\\sim 10-15 \\mpc$. The amplitude of $v_{12}(r)$ is sensitive to the assumed shape of $\\sigma(r)$; if the latter deviates substantially from a virialized form on small scale, our best fit amplitude of $v_{12}(r)$ can deviate by a factor of two.
Karl B Fisher; Marc Davis; Michael A Strauss; Amos Yahil; John P Huchra
Mitigation of Voltage and Current Harmonics in Grid-Connected Microgrids Savaghebi, Mehdi; Guerro, Josep M.; Jalilian, Alireza ; Quintero, Juan Carlos Vasquez
Mitigation of Voltage and Current Harmonics in Grid-Connected Microgrids Savaghebi, Mehdi; Guerro-Connected Microgrids. In Proceedings of the 21st IEEE International Symposium on Industrial Electronics (ISIE), 2012;Mitigation of Voltage and Current Harmonics in Grid-Connected Microgrids Mehdi Savaghebi1 , Josep M. Guerrero
The present invention relates to switching laser beams out of laser cavities, and more particularly, it relates to the use of generating harmonics of the laser beam to accomplish the switching. When laser light is generatd in a laser cavity the problem arises of how to switch the laser light out of the cavity in order to make use of the resulting laser beam in a well known multitude of ways. These uses include range finding, communication, remote sensing, medical surgery, laser fusion applications and many more. The switch-out problem becomes more difficult as the size of the laser aperture grows such as in laser fusion applications. The final amplifier stages of the Nova and Novette lasers at Lawrence Livermore National Laboratory are 46 centimeters with the laser beam expanded to 74 centimeters thereafter. Larger aperture lasers are planned.
Haas, R.A.; Henesian, M.A.
Coupling interaction between the power coupler and the third harmonic superconducting cavity
Fermilab has developed a third harmonic superconducting cavity operating at the frequency of 3.9 GHz to improve the beam performance for the FLASH user facility at DESY. It is interesting to investigate the coupling interaction between the SRF cavity and the power coupler with or without beam loading. The coupling of the power coupler to the cavity needs to be determined to minimize the power consumption and guarantee the best performance for a given beam current. In this paper, we build and analyze an equivalent circuit model containing a series of lumped elements to represent the resonant system. An analytic solution of the required power from the generator as a function of the system parameters has also been given based on a vector diagram.
Li, Jianjian; Solyak, Nikolay; /Fermilab; Wong, Thomas; /IIT, Chicago
Regional Modelling of the Southern African Geomagnetic Field using Harmonic Splines
Over the southern African region the geomagnetic field is weak and changes rapidly. For this area series of geomagnetic field measurements exist since the 1950s. We take advantage of the existing repeat station surveys and observatory annual means, and clean these data sets by eliminating jumps and minimising external field contributions in the original time series. This unique data set allows us to obtain a detailed view of the geomagnetic field behaviour in space and time by computing a regional model. For this, we use a system of representation similar to harmonic splines. Initially, the technique is systematically tested on synthetic data. After systematically testing the method on synthetic data, we derive a model for 1961 to 2001 that gives a detailed view of the fast changes of the geomagnetic field in this region.
Geese, Anne; Lesur, Vincent; Mandea, Mioara
The Simple Harmonic Rotor with Motion Hinged By of a Helicopter
Summary.--In simple harmonic oscillation of the helicopter with hinged blades, the tip-path plane is tilted with respect to the shaft in the plane of oscillation and in the plane perpendicular to it. The angles of tilt can be expressed as functions of angular velocity and acceleration. The influence ' of the acceleration term on the dynamic stability of the helicopter is small. The expressions for angles of tilt due to angular velocity can be simplified to the expressions obtained in previous work under assumptions of quasi-static conditions. 1. I~troductio~.--It has been shown in Ref. 1 that when the rotor shaft of a helicopter tilts with constant pitching velocity, the tip-path plane lags behind the shaft and also tilts Sideways. These angles of lag and sidetilt were found to be proportional to the pitching velocity of the shaft and the following expressions were derived: Oal _. Of yD............. (1)
J. K. Zbrozek; Dipl. Eng; J. K. Zbxoze
Investigation of Ion Absorption of the High Harmonic Fast Wave in NSTX using HPRT
Understanding high harmonic fast wave (HHFW) power absorption by ions in a spherical torus (ST) is of critical importance to assessing the wave's viability as a means of heating and especially driving current. In this work, the HPRT code is used to calculate absorption for helium and deuterium, with and without minority hydrogen in National Spherical Torus Experiment (NSTX) plasmas using experimental EFIT code equilibria and kinetic profiles. HPRT is a two-dimensional ray-tracing code which uses the full hot plasma dielectric to compute the perpendicular wave number along the hot electron and cold ion plasma ray path. Ion and electron absorption dependence on antenna phasing, ion temperature, beta (subscript t), and minority temperature and concentration is analyzed. These results form the basis for comparisons with other codes, such as CURRAY, METS, TORIC, and AORSA.
Rosenberg, A.; Menard, J.E.; and LeBlanc, B.P.
Analytical transformed harmonic oscillator basis for continuum discretized coupled channels calculations
A new method for continuum discretization in continuum-discretized coupled-channels calculations is proposed. The method is based on an analytic local-scale transformation of the harmonic-oscillator wave functions proposed for other purposes in a recent work [Karatagladis et al., Phys. Rev. C 71, 064601 (2005)]. The new approach is compared with the standard method of continuum discretization in terms of energy bins for the reactions d+{sup 58}Ni at 80 MeV, {sup 6}Li+{sup 40}Ca at 156 MeV, and {sup 6}He+{sup 208}Pb at 22 MeV and 240 MeV/nucleon. In all cases very good agreement between both approaches is found.
Moro, A. M.; Arias, J. M. [Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Gomez-Camacho, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Facultad de Fisica, Universidad de Sevilla, Apartado 1065, E-41080 Sevilla (Spain); Centro Nacional de Aceleradores, Avda Thomas A. Edison, E-41092 Sevilla (Spain); Perez-Bernal, F. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain)
Numerical Verification of Bounce Harmonic Resonances in Neoclassical Toroidal Viscosity for Tokamaks
This Letter presents the rst numerical veri cation for the bounce-harmonic (BH) resonance phenomena of the neoclassical transport in a tokamak perturbed by non-axisymmetric magnetic elds. The BH resonances were predicted by analytic theories of neoclassical toroidal viscosity (NTV), as the parallel and perpendicular drift motions can be resonant and result in a great enhancement of the radial momentum transport. A new drift-kinetic #14;f guiding-center particle code, POCA, clearly veri ed that the perpendicular drift motions can reduce the transport by phase-mixing, but in the BH resonances the motions can form closed orbits and particles radially drift out fast. The POCA calculations on resulting NTV torque are largely consistent with analytic calculations, and show that the BH resonances can easily dominate the NTV torque when a plasma rotates in the perturbed tokamak and therefore is a critical physics for predicting the rotation and stability in ITER. __________________________________________________
Kimin Kim, Jong-Kyu Park and Allen H. Boozer
Dynamics and decoherence of two cold bosons in a one-dimensional harmonic trap
We study dynamics of two interacting ultracold Bose atoms in a harmonic oscillator potential in one spatial dimension. Making use of the exact solution of the eigenvalue problem of a particle in the {delta}-like potential, we study the time evolution of an initially separable state of two particles. The corresponding time-dependent single-particle density matrix is obtained and diagonalized, and single-particle orbitals are found. This allows us to study decoherence as well as creation of entanglement during the dynamics. The evolution of the orbital corresponding to the largest eigenvalue is then compared to the evolution according to the Gross-Pitaevskii equation. We show that if initially the center of mass and relative degrees of freedom are entangled, then the Gross-Pitaevskii equation fails to reproduce the exact dynamics and entanglement is produced dynamically. We stress that predictions of our study can be verified experimentally in an optical lattice in the low-tunneling limit.
Sowinski, Tomasz [Instytut Fizyki PAN, Al. Lotnikow 32/46, PL-02-668 Warszawa (Poland); Wydzial Biologii i Nauk o Srodowisku UKSW, ul. Woycickiego 1/3, PL-01-938 Warszawa (Poland); Brewczyk, Miroslaw [Wydzial Fizyki, Uniwersytet w Bialymstoku, ul. Lipowa 41, PL-15-424 Bialystok (Poland); Gajda, Mariusz [Instytut Fizyki PAN, Al. Lotnikow 32/46, PL-02-668 Warszawa (Poland); Wydzial Matematyczno-Przyrodniczy SNS UKSW, Al. Lotnikow 32/46, PL-02-668 Warszawa (Poland); RzaPzewski, Kazimierz [Wydzial Matematyczno-Przyrodniczy SNS UKSW, Al. Lotnikow 32/46, PL-02-668 Warszawa (Poland); Centrum Fizyki Teoretycznej PAN, Al. Lotnikow 32/46, PL-02-668 Warszawa (Poland)
Three attractively interacting fermions in a harmonic trap: Exact solution, ferromagnetism, and high-temperature thermodynamics
Three fermions with strongly repulsive interactions in a spherical harmonic trap constitute the simplest nontrivial system that can exhibit the onset of itinerant ferromagnetism. Here, we present exact solutions for three trapped, attractively interacting fermions near a Feshbach resonance. We analyze energy levels on the upper branch of the resonance where the atomic interaction is effectively repulsive. When the s-wave scattering length a is sufficiently positive, three fully polarized fermions are energetically stable against a single spin-flip, indicating the possibility of itinerant ferromagnetism, as inferred in the recent experiment. We also investigate the high-temperature thermodynamics of a strongly repulsive or attractive Fermi gas using a quantum virial expansion. The second and third virial coefficients are calculated. The resulting equations of state can be tested in future quantitative experimental measurements at high temperatures and can provide a useful benchmark for quantum Monte Carlo simulations.
Liu Xiaji; Hu Hui; Drummond, Peter D. [ARC Centre of Excellence for Quantum-Atom Optics, Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122 (Australia)
PT-Rotations, PT-Spherical Harmonics and the PT-Hydrogen Atom
We have constructed a set of non-Hermitian operators that satisfy the commutation relations of the SO(3)-Lie algebra. It is shown that this operators generate rotations in the configuration space and not in the momentum space but in a modified non-Hermitian momentum space. This generators are related with a new type of spherical harmonics that result to be PT-orthonormal. Additionally, we have shown that this operators represent conserved quantities for a non-Hermitian Hamiltonian with an additional complex term. As a particular case, the solutions of the corresponding PT-Hydrogen atom that includes a complex term are obtained, and it is found that a non-Hermitian Runge-Lenz vector is a conserved quantity. In this way, we obtain a set of non-Hermitian operators that satisfy the SO(4)-Lie algebra.
Juan M. Romero; R. Bernal-Jaquez; O. Gonzalez-Gaxiola
Third harmonic flow of charged particles in Au + Au collisions at ?s[subscript NN]=200�GeV
We report measurements of the third harmonic coefficient of the azimuthal anisotropy, v[subscript 3], known as triangular flow. The analysis is for charged particles in Au+Au collisions at ?s[subscript NN]=200 GeV, based ...
Betancourt, M. J.
CFL Labeling Harmonization in the United States, China, Brazil andELI Member Countries: Specifications, Testing, and MutualRecognition
This report examines critical differences among energy-efficient labeling programs for CFLs in Brazil, China, the United States, and the seven members of the international Efficient Lighting Initiative (ELI) in terms of technical specifications and test procedures, and review issues related to international harmonization of these standards.
Fridley, David; Lin, Jiang; Denver, Andrea; Biermayer, Peter; Dillavou, Tyler
Abstract--This paper presents the harmonic analysis of offshore wind farm (OWF) models with full converters
. Hjerrild, are with DONG Energy, Denmark (e-mail:, email@example.com, email@example.com). C. L. Bak is with the Institute of Energy Technology, Aalborg University, Denmark (e-mail: email@example.com). effects of harmonics [15]. Fig. 2 Wind turbines from Burbo Bank Offshore Wind Farm (daylife.com). In order to investigate
Sub-Millimetre Wave Sub-Harmonically Pumped Image-Rejection Schottky Mixers for STEAM-R
Sub-Millimetre Wave Sub-Harmonically Pumped Image- Rejection Schottky Mixers for STEAM-R S. P. Rea = 343.5 - 355.5 GHz switch The PREMIER Mission The STEAM-R Instrument PREMIER (PRocess Exploration-sounder (MWLS) on the same satellite platform. The MWLS is the latest iteration of the STEAM-R instrument
On the harmonics of the low-frequency quasi-periodic oscillation in GRS 1915+105
GRS 1915+105 is a widely studied black hole binary, well known because of its extremely fast and complex variability. Flaring periods of high variability alternate with "stable" phases (the plateaux) when the flux is low, the spectra are hard and the timing properties of the source are similar to those of a number of black hole candidates in hard spectral state. In the plateaux the power density spectra are dominated by a low frequency quasi periodic oscillation (LFQPO) superposed onto a band limited noise continuum and accompanied by at least one harmonic. In this paper we focus on three plateaux, presenting the analysis of the power density spectra and in particular of the LFQPO and its harmonics. While plotting the LFQPO and all the harmonics together on a frequency-width plane, we found the presence of a positive trend of broadening when the frequency increases. This trend can shed light in the nature of the harmonic content of the LFQPO and challenges the usual interpretation of these timing features.
Ratti, E M; Motta, S E
Measurements and modeling of laser irradiance in the high-power third-harmonic Nova focus: Volume B, Data book
This document contains analysis of third-harmonic equivalent plane photographs obtained in the 2PJW{underscore}3wspot series and described in the report under the same title, Volume A. The photographs that are analyzed in this data book are summarized. A description of the analysis output is included.
Wegner, P.
Life Cycle Greenhouse Gas Emissions of Utility-Scale Wind Power: Systematic Review and Harmonization
A systematic review and harmonization of life cycle assessment (LCA) literature of utility-scale wind power systems was performed to determine the causes of and, where possible, reduce variability in estimates of life cycle greenhouse gas (GHG) emissions. Screening of approximately 240 LCAs of onshore and offshore systems yielded 72 references meeting minimum thresholds for quality, transparency, and relevance. Of those, 49 references provided 126 estimates of life cycle GHG emissions. Published estimates ranged from 1.7 to 81 grams CO{sub 2}-equivalent per kilowatt-hour (g CO{sub 2}-eq/kWh), with median and interquartile range (IQR) both at 12 g CO{sub 2}-eq/kWh. After adjusting the published estimates to use consistent gross system boundaries and values for several important system parameters, the total range was reduced by 47% to 3.0 to 45 g CO{sub 2}-eq/kWh and the IQR was reduced by 14% to 10 g CO{sub 2}-eq/kWh, while the median remained relatively constant (11 g CO{sub 2}-eq/kWh). Harmonization of capacity factor resulted in the largest reduction in variability in life cycle GHG emission estimates. This study concludes that the large number of previously published life cycle GHG emission estimates of wind power systems and their tight distribution suggest that new process-based LCAs of similar wind turbine technologies are unlikely to differ greatly. However, additional consequential LCAs would enhance the understanding of true life cycle GHG emissions of wind power (e.g., changes to other generators operations when wind electricity is added to the grid), although even those are unlikely to fundamentally change the comparison of wind to other electricity generation sources.
Dolan, S. L.; Heath, G. A.
Transportation Market Distortions
of Highways, Volpe National Transportation Systems Center (Evaluating Criticism of Transportation Costing, VictoriaFrom Here: Evaluating Transportation Diversity, Victoria
Litman, Todd
Transport Prices and Markets, Victoria Transport PolicySurvey: Survey Suggests Market-Based Vision of Smart Growth,G. 1996. Roads in a Market Economy, Avebury (Aldershot).
Sources of Distortion
..., ASM International, 2009, p 106�??126ASM Handbook, Vol 22A, Fundamentals of Modeling for Metals ProcessingD. S. MacKenzie and A. L. Banka,
Frustration by competing interactions in the highly-distorted double perovskites La2NaB'O6 (B' = Ru, Os)
The usual classical behaviour of S = 3/2, B-site ordered double perovskites generally results in simple, commensurate magnetic ground states. In contrast, heat capacity and neutron powder diffraction measurements for the S = 3/2 systems La2NaB'O6 (B = Ru, Os) reveal an incommensurate magnetic ground state for La2NaRuO6 and a drastically suppressed ordered moment for La2NaOsO6. This behaviour is attributed to the large monoclinic structural distortions of these double perovskites. The distortions have the effect of weakening the nearest neighbour superexchange interactions, presumably to an energy scale that is comparable to the next nearest neighbour superexchange. The exotic ground states in these materials can then arise from a competition between these two types of antiferromagnetic interactions, providing a novel mechanism for achieving frustration in the double perovskite family.
Aczel, Adam A [ORNL; Bugaris, Dan [University of South Carolina; Li, Ling [University of Tennessee, Knoxville (UTK); Yan, Jiaqiang [ORNL; Dela Cruz, Clarina R [ORNL; Zur Loye, Hans-Conrad [University of South Carolina; Nagler, Stephen E [ORNL
This paper reports intermediate-scale instability in a single-stage power-factor-correction (PFC) power supply that employs a cascade configuration of a boost stage operating in discontinuous conduction mode (DCM) and a forward stage operating in continuous conduction mode (CCM). The two stages combine into a single stage by sharing one main switch and one control loop to achieve input PFC and tight output regulation. The main results are given by �exact � cycle-bycycle circuit simulations. The effect of the intermediate-scale instability on the attainable power factor is illustrated in terms of total harmonic distortion (THD) which is found by taking the Fast Fourier Transform (FFT) of the input current. The intermediate-scale instability usually manifests itself as local oscillations within a line cycle. Based on the stability analysis of a buck converter operating in CCM, the underlying mechanism of such instability can be attributed to the Hopf bifurcation that occurred in CCM forward stage. Finally, experimental results are presented for verification purposes.
Dong Dai; Chik. Tse; Bo Zhang; Xikui Ma
New single-switch three-phase high power factor rectifiers using multi-resonant zero current switching
Abstract � A new family of single-switch three-phase highpower-factor rectifiers, which have continuous input and output currents, is introduced. By using a multiresonant scheme, the transistor operates with zero-current switching (ZCS), and the diodes operate with zero-voltage switching (ZVS). These multiresonant rectifiers with a single transistor are capable of drawing a higher quality input-current waveform at nearly unity power factor and lower stresses than quasi-resonant rectifiers. Buck-type converters are used for the power stage, and, hence, the output voltage is lower than the input voltage. Moreover, these rectifiers have a wide load range and low stresses on semiconductor devices. From the analysis, normalized characteristics of the rectifier are derived. The design and breadboard implementation of the rectifier delivering 147 V? � at 6 kW from a 30 240-V???@vvA input is described. The total harmonic distortion (THD) of the line current is less than 5%, and the system efficiency is about 94% at the full load. Index Terms � Frequency control, multiresonant, power factor correction (PFC), resonant converters, three-phase rectifiers,
Yungtaek Jang; Robert W. Erickson
Abstract � Power inverters are used to convert the D.C power produced by the solar photovoltaic cell into AC. This paper presents a novel Adaptive Hysteresis Current Controller to control the inverter, used in the solar photovoltaic cell. The proposed controller is capable of reducing the total harmonic distortion and to provide constant switching frequency. The mathematical model of Photovoltaic array is developed using the Newton�s method using the parameter obtained from a commercial photovoltaic data sheet under variable weather conditions, in which the effect of irradiance and temperature are considered. The modeled Photovoltaic array is interfaced with DC-DC boost converter, AC-DC inverter and load. A DC-DC boost converter is used to step up the input DC voltage of the Photovoltaic array while the DC-AC single-phase inverter converts the input DC comes from boost converter into AC. The performance of the proposed controller of inverter is evaluated through MATLAB-Simulation. The results obtained with the proposed algorithm are compared with those obtained when using conventional fixed hysteresis current controller for single-phase photovoltaic inverter in terms of THD and switching frequency.
unknown authors
Direct probing of electronic density distribution of a Rydberg state by high-order harmonic generation in a few-cycle laser pulse
We demonstrate that the electronic density distribution of a Rydberg state can be probed directly using a broadband harmonic spectrum in a few-cycle laser pulse. Taking advantage of the large orbital radius of a Rydberg state, we show that the Rydberg electron can be accelerated directly toward the core under the influence of a few-cycle laser pulse, leading to recombination and emission of harmonic photons. In this case the initial position of the electron and the harmonic order form a one-to-one correspondence, resulting in a realization of direct probing of the density distribution of the initial Rydberg state.
Zhai Zhen; Fu Panming; Wang Bingbing [Laboratory of Optical Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Chen Jing [Center for Nonlinear Studies, Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yan Zongchao [Department of Physics, University of New Brunswick, P.O. Box 4400, Fredericton, New Brunswick E3B 5A3 (Canada)
Phase matching of high order harmonic generation using dynamic phase modulation caused by a non-collinear modulation pulse
Phase matching high harmonic generation (HHG) uses a single, long duration non-collinear modulating pulse intersecting the driving pulse. A femtosecond driving pulse is focused into an HHG medium (such as a noble gas) to cause high-harmonic generation (HHG), for example in the X-ray region of the spectrum, via electrons separating from and recombining with gas atoms. A non-collinear pulse intersects the driving pulse within the gas, and modulates the field seen by the electrons while separated from their atoms. The modulating pulse is low power and long duration, and its frequency and amplitude is chosen to improve HHG phase matching by increasing the areas of constructive interference between the driving pulse and the HHG, relative to the areas of destructive interference.
Cohen, Oren (Boulder, CO); Kapteyn, Henry C. (Boulder, CO); Mumane, Margaret M. (Boulder, CO)
Revealing molecular structure and dynamics through high-order harmonic generation driven by mid-IR fields
High-order harmonic generation (HHG) from molecules produces spectra that are modulated by interferences that encode both the static structure and the electron dynamics initiated by interaction with the laser field. Using a midinfrared (mid-IR) laser at 1300 nm, we are able to study the region of the harmonic spectrum containing such interferences in CO{sub 2} over a wide range of intensities. This allows for isolation and characterization of interference minima arising due to subcycle electronic dynamics triggered by the laser field, which had previously been identified but not systematically separated. Our experimental and theoretical results demonstrate important steps toward combining attosecond temporal and angstrom-scale spatial resolution in molecular HHG imaging.
Torres, R.; Siegel, T.; Brugnera, L.; Ivanov, M. Yu.; Marangos, J. P. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Procino, I. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Underwood, Jonathan G. [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom); Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Altucci, C.; Velotta, R. [Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia and Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', Naples (Italy); Springate, E.; Froud, C.; Turcu, I. C. E. [Central Laser Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 0QX (United Kingdom); Patchkovskii, S. [Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Smirnova, O. [Max-Born-Institute, 2a Max-Born-Strasse, Berlin D-12489 (Germany)
Industrial harmonic analysis system for magnetic measurements of SSC collider arc and high energy booster corrector magnets
The SSCL collider arc and high energy booster corrector magnets are 50 mm bore cryogenic magnets. The integral strength and harmonics will be measured by industry at full current at 4.2 K and at plus and minus 400 mA at room temperature. Dipoles, quadrupoles, and sextupoles have error tolerances of a few tens of units. A prototype harmonic analysis system for magnetic measurements of production and prototype dipole, quadrupole and sextupole magnets has been designed and is being fabricated. We describe the criteria for search coil designs, data acquisition system hardware and software. Radial search coil arrays are being fabricated utilizing multifilar wire. Two digital integrators will allow simultaneous accumulation of unbucked and bucked configurations.
Green, M.I.; Sponsel, R.; Sylvester, C.
Real time selective harmonic minimization for multilevel inverters using genetic algorithm and artifical neural network angle generation
The work developed here proposes a methodology for calculating switching angles for varying DC sources in a multilevel cascaded H-bridges converter. In this approach the required fundamental is achieved, the lower harmonics are minimized, and the system can be implemented in real time with low memory requirements. Genetic algorithm (GA) is the stochastic search method to find the solution for the set of equations where the input voltages are the known variables and the switching angles are the unknown variables. With the dataset generated by GA, an artificial neural network (ANN) is trained to store the solutions without excessive memory storage requirements. This trained ANN then senses the voltage of each cell and produces the switching angles in order to regulate the fundamental at 120 V and eliminate or minimize the low order harmonics while operating in real time.
Filho, Faete J [ORNL; Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL
Application of the Space-Time Method to Stimulated Raman Adiabatic Passage on the Simple Harmonic Oscillator
The space-time method is applied to a model system-the Simple Harmonic Oscillator in a laser field to simulate the Stimulated Raman Adiabatic Passage (STIRAP) process. The Space-Time method is a computational theory first introduced by Weatherford et. al. to solve Time-Dependent Systems with one boundary value and applied to electron spin system with invariant Hamiltonian [Journal of Molecular Structure {\\bf 592} 47]. The implementation in the present work provides an efficient and general way to solve the Time-Dependent Schr{\\"o}dinger Equation and can be applied to multi-state systems. The algorithm for simulating the Simple Harmonic Oscillator STIRAP can be applied to solve STIRAP problems for complex systems.
Xingjun Zhang; Charles A. Weatherford
Zhang, Xingjun
Real Time Selective Harmonic Minimization for Multilevel Inverters Connected to Solar Panels Using Artificial Neural Network Angle Generation
This work approximates the selective harmonic elimination problem using artificial neural networks (ANNs) to generate the switching angles in an 11-level full-bridge cascade inverter powered by five varying dc input sources. Each of the five full bridges of the cascade inverter was connected to a separate 195-W solar panel. The angles were chosen such that the fundamental was kept constant and the low-order harmonics were minimized or eliminated. A nondeterministic method is used to solve the system for the angles and to obtain the data set for the ANN training. The method also provides a set of acceptable solutions in the space where solutions do not exist by analytical methods. The trained ANN is a suitable tool that brings a small generalization effect on the angles' precision and is able to perform in real time (50-/60-Hz time window).
Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL; Filho, Faete [ORNL; Cao, Yue [ORNL
Exact Solution for the Stokes Problem of an Infinite Cylinder in a Fluid with Harmonic Boundary Conditions at Infinity
We present an exact solution for the time-dependent Stokes problem of an infinite cylinder of radius r=a in a fluid with harmonic boundary conditions at infinity. This is a 3-dimensional problem but, because of translational invariance along the axis of the cylinder it effectively reduces to a 2-dimensional one. The Stokes problem being a linear reduction of the full Navier-Stokes equations, we show how to satisfy the no-slip boundary condition at the cylinder surface and the harmonic boundary condition at infinity, exhibit the full velocity field for radius r>a, and discuss the nature of the solutions for the specific case of air at sea level.
Andreas N. Vollmayr; Jan-Moritz P. Franosch; J. Leo van Hemmen
A quantum exactly solvable non-linear oscillator with quasi-harmonic behaviour
The quantum version of a non-linear oscillator, previously analyzed at the classical level, is studied. This is a problem of quantization of a system with position-dependent mass of the form m = (1 + {lambda}x {sup 2}){sup -1} and with a {lambda}-dependent non-polynomial rational potential. This {lambda}-dependent system can be considered as a deformation of the harmonic oscillator in the sense that for {lambda} {sup {yields}} 0 all the characteristics of the linear oscillator are recovered. First, the {lambda}-dependent Schroedinger equation is exactly solved as a Sturm-Liouville problem, and the {lambda}-dependent eigenenergies and eigenfunctions are obtained for both {lambda} > 0 and {lambda} < 0. The {lambda}-dependent wave functions appear as related with a family of orthogonal polynomials that can be considered as {lambda}-deformations of the standard Hermite polynomials. In the second part, the {lambda}-dependent Schroedinger equation is solved by using the Schroedinger factorization method, the theory of intertwined Hamiltonians, and the property of shape invariance as an approach. Finally, the new family of orthogonal polynomials is studied. We prove the existence of a {lambda}-dependent Rodrigues formula, a generating function and {lambda}-dependent recursion relations between polynomials of different orders.
Carinena, Jose F. [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain)]. E-mail: email@example.com; Ranada, Manuel F. [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain)]. E-mail: email@example.com; Santander, Mariano [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Valladolid, 47011 Valladolid (Spain)]. E-mail: email@example.com
The quantum harmonic oscillator on the sphere and the hyperbolic plane
A nonlinear model of the quantum harmonic oscillator on two-dimensional space of constant curvature is exactly solved. This model depends on a parameter {lambda} that is related with the curvature of the space. First, the relation with other approaches is discussed and then the classical system is quantized by analyzing the symmetries of the metric (Killing vectors), obtaining a {lambda}-dependent invariant measure d{mu}{sub {lambda}} and expressing the Hamiltonian as a function of the Noether momenta. In the second part, the quantum superintegrability of the Hamiltonian and the multiple separability of the Schroedinger equation is studied. Two {lambda}-dependent Sturm-Liouville problems, related with two different {lambda}-deformations of the Hermite equation, are obtained. This leads to the study of two {lambda}-dependent families of orthogonal polynomials both related with the Hermite polynomials. Finally the wave functions {psi}{sub m,n} and the energies E{sub m,n} of the bound states are exactly obtained in both the sphere S{sup 2} and the hyperbolic plane H{sup 2}.
Carinena, Jose F. [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain)], E-mail: email@example.com; Ranada, Manuel F. [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain)], E-mail: firstname.lastname@example.com; Santander, Mariano [Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Valladolid, 47011 Valladolid (Spain)], E-mail: firstname.lastname@example.com
Exploration of High Harmonic Fast Wave Heating on the National Spherical Torus Experiment
High Harmonic Fast Wave (HHFW) heating has been proposed as a particularly attractive means for plasma heating and current drive in the high-beta plasmas that are achievable in spherical torus (ST) devices. The National Spherical Torus Experiment (NSTX) [Ono, M., Kaye, S.M., Neumeyer, S., et al., Proceedings, 18th IEEE/NPSS Symposium on Fusion Engineering, Albuquerque, 1999, (IEEE, Piscataway, NJ (1999), p. 53.)] is such a device. An radio-frequency (rf) heating system has been installed on NSTX to explore the physics of HHFW heating, current drive via rf waves and for use as a tool to demonstrate the attractiveness of the ST concept as a fusion device. To date, experiments have demonstrated many of the theoretical predictions for HHFW. In particular, strong wave absorption on electrons over a wide range of plasma parameters and wave parallel phase velocities, wave acceleration of energetic ions, and indications of current drive for directed wave spectra have been observed. In addition HHFW heating has been used to explore the energy transport properties of NSTX plasmas, to create H-mode (high-confinement mode) discharges with a large fraction of bootstrap current and to control the plasma current profile during the early stages of the discharge.
J.R. Wilson; R.E. Bell; S. Bernabei; M. Bitter; P. Bonoli; D. Gates; J. Hosea; B. LeBlanc; T.K. Mau; S. Medley; J. Menard; D. Mueller; M. Ono; C.K. Phillips; R.I. Pinsker; R. Raman; A. Rosenberg; P. Ryan; S. Sabbagh; D. Stutman; D. Swain; Y. Takase; J. Wilgen; the NSTX Team
The harmonization of Canadian and U.S. window programs and standards. Final report
The window and door industry in North America have a strong interest in harmonizing US and Canadian rating procedures and standards for predicting the thermal performance of their products. The costs and time associated with complying with the requirements in both countries are significant and could be reduced through reciprocity. The purpose of this paper is to compare the US and Canadian rating programs. Joint efforts between the US and Canada can use this information to focus on reconciling the differences and to work towards reciprocity. The following identifies the applicable procedures and standards for both countries, and summarizes the major differences in the products that are covered, the sizes that are used, the U-factor and solar heat gain coefficient calculational and test methods, air leakage measurement, prediction of annual energy use, condensation resistance methods, reporting requirements, and accreditation and certification programs. The major differences between the system s are identified and recommendations are made to achieve reciprocity. The appendix contains a paper that is a synopsis of the findings from this study.
Anthropometry for WorldSID, a World-Harmonized Midsize Male Side Impact Crash Dummy
The WorldSID project is a global effort to design a new generation side impact crash test dummy under the direction of the International Organization for Standardization (ISO). The first WorldSID crash dummy will represent a world-harmonized mid-size adult male. This paper discusses the research and rationale undertaken to define the anthropometry of a world standard midsize male in the typical automotive seated posture. Various anthropometry databases are compared region by region and in terms of the key dimensions needed for crash dummy design. The Anthropometry for Motor Vehicle Occupants (AMVO) dataset, as established by the University of Michigan Transportation Research Institute (UMTRI), is selected as the basis for the WorldSID mid-size male, updated to include revisions to the pelvis bone location. The proposed mass of the dummy is 77.3kg with full arms. The rationale for the selected mass is discussed. The joint location and surface landmark database is appended to this paper.
S. Moss; Z. Wang; M. Salloum; M. Reed; M. Van Ratingen; D. Cesari; R. Scherer; T. Uchimura; M. Beusenberg
The phase diagram of ice: a quasi-harmonic study based on a flexible water model
The phase diagram of ice is studied by a quasi-harmonic approximation. The free energy of all experimentally known ice phases has been calculated with the flexible q-TIP4P/F model of water. The only exception is the high pressure ice X, in which the presence of symmetric O-H-O bonds prevents its modeling with this empirical interatomic potential. The simplicity of our approach allows us to study ice phases at state points of the T-P plane that have been omitted in previous simulations using free energy methods based on thermodynamic integration. The effect in the phase diagram of averaging the proton disorder that appears in several ice phases has been studied. It is found particularly relevant for ice III, at least for cell sizes typically used in phase coexistence simulations. New insight into the capability of the employed water model to describe the coexistence of ice phases is presented. We find that the H-ordered ices IX and XIV, as well as the H-disordered ice XII, are particularly stable for this wate...
Ramirez, R; Herrero, C P
Infrared and ultraviolet cutoffs in variational calculations with a harmonic oscillator basis
I abstract from a recent publication [1] the motivations for, analysis in and conclusions of a study of the ultraviolet and infrared momentum regulators induced by the necessary truncation of the model spaces formed by a variational trial wave function. This trial function is built systematically from a complete set of many-body basis states based upon three-dimensional harmonic oscillator (HO) functions. Each model space is defined by a truncation of the expansion characterized by a counting number (N) and by the intrinsic scale ($\\hbar\\omega$) of the HO basis. Extending both the uv cutoff to infinity and the ir cutoff to zero is prescribed for a converged calculation. In [1] we established practical procedures which utilize these regulators to obtain the extrapolated result from sequences of calculations with model spaces. Finally, I update this subject by mentioning recent work on our extrapolation prescriptions which have appeared since the submission of [1]. The numerical example chosen for this contribution consists of calculations of the ground state energy of the triton with the "bare" and "soft" Idaho N3LO nucleon-nucleon (NN) interaction.
Sidney A Coon
Fluctuations in the Gravitational, Strong and Weak Nuclear Fields through an Effective Harmonic Oscillator Model
We propose an effective harmonic oscillator model in order to treat the fluctuations of the gravitational, strong and weak nuclear fields. With respect to the gravitational field, first we use the model to estimate its fluctuating strength, necessary to decohere the wavefunction of a cubic centimeter of air at the standard temperature and pressure conditions. Second, the fluctuation of a point mass through a distance equal to the Planck length leads to the self-gravitational interaction of a particle, which can be related to its de Broglie frequency. Third, by making the equality of the fluctuating field strength with the gravitational field of a mass M at half of its Schwarzschild radius, we obtain an estimate of the mass of the Universe. We also consider the fluctuations of the strong nuclear field, as a means to estimate the separation in energy between the ground state and the centroid of the excitated states of the nucleon. Finally, taking into account the neutron-proton mass difference, we use the fluctuations of the weak nuclear field in order to evaluate the weak coupling constant.
P. R. Silva
Variable order spherical harmonic expansion scheme for the radiative transport equation using finite elements
Highlights: {yields} We developed a variable order global basis scheme to solve light transport in 3D. {yields} Based on finite elements, the method can be applied to a wide class of geometries. {yields} It is computationally cheap when compared to the fixed order scheme. {yields} Comparisons with local basis method and other models demonstrate its accuracy. {yields} Addresses problems encountered n modeling of light transport in human brain. - Abstract: We propose the P{sub N} approximation based on a finite element framework for solving the radiative transport equation with optical tomography as the primary application area. The key idea is to employ a variable order spherical harmonic expansion for angular discretization based on the proximity to the source and the local scattering coefficient. The proposed scheme is shown to be computationally efficient compared to employing homogeneously high orders of expansion everywhere in the domain. In addition the numerical method is shown to accurately describe the void regions encountered in the forward modeling of real-life specimens such as infant brains. The accuracy of the method is demonstrated over three model problems where the P{sub N} approximation is compared against Monte Carlo simulations and other state-of-the-art methods.
Surya Mohan, P., E-mail: firstname.lastname@example.com [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Tarvainen, Tanja, E-mail: firstname.lastname@example.com [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio (Finland); Schweiger, Martin, E-mail: firstname.lastname@example.com [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom); Pulkkinen, Aki, E-mail: firstname.lastname@example.com [Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio (Finland); Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, 2075 Bayview Ave., Toronto, M4N 3M5 (Canada); Arridge, Simon R., E-mail: firstname.lastname@example.com [Department of Computer Science, University College London, Gower Street, London WC1E 6BT (United Kingdom)
Harmonic analysis of irradiation asymmetry for cylindrical implosions driven by high-frequency rotating ion beams
Cylindrical implosions driven by intense heavy ions beams should be instrumental in a near future to study High Energy Density Matter. By rotating the beam by means of a high frequency wobbler, it should be possible to deposit energy in the outer layers of a cylinder, compressing the material deposited in its core. The beam temporal profile should however generate an inevitable irradiation asymmetry likely to feed the Rayleigh-Taylor instability (RTI) during the implosion phase. In this paper, we compute the Fourier components of the target irradiation in order to make the junction with previous works on RTI performed in this setting. Implementing a 1D and 2D beam models, we find these components can be expressed exactly in terms of the Fourier transform of the temporal beam profile. If $T$ is the beam duration and $\\Omega$ its rotation frequency, "magic products" $\\Omega T$ can be identified which cancel the first harmonic of the deposited density, resulting in an improved irradiation symmetry.
Bret, Antoine; Tahir, Naeem
To support the North American Energy Working Group's Expert Group on Energy Efficiency (NAEWG-EE), USDOE commissioned the Collaborative Labeling and Appliance Standards Program (CLASP) to prepare a resource document comparing current standards, labels, and test procedure regulations in Canada, Mexico, and the United States. The resulting document reached the following conclusions: Out of 24 energy-using products for which at least one of the three countries has energy efficiency regulations, three products -- refrigerators/freezers, split system central air conditioners, and room air conditioners -- have similar or identical minimum energy performance standards (MEPS) in the three countries. These same three products, as well as three-phase motors, have similar or identical test procedures throughout the region. There are 10 products with different MEPS and test procedures, but which have the short-term potential to develop common test procedures, MEPS, and/or labels. Three other noteworthy areas where possible energy efficiency initiatives have potential for harmonization are standby losses, uniform endorsement labels, and a new standard or label on windows. This paper explains these conclusions and presents the underlying comparative data.
Vanwiemcgrory, Laura; Wiel, Stephen; Van Wie McGrory, Laura; Harrington, Lloyd
Analysis of inverter models and harmonic propagation. Part III. Transient processes in inverter models
Part III of a three part study presents the theoretical analysis and the experimental verification of transient processes that arise in the photovoltaic power system during its normal commutational operations. A general description of the transient processes problem and the method of analysis is presented. The transient processes in the inverter model with an inductive filter are analyzed for both the discontinuous and the continuous currents on the dc side of the inverter, and the problem of transient processes due to the change in illumination level is discussed. Transient processes in the inverter model with capacitive filter are analyzed with special emphasis on the process that arises in the photovoltaic power system immediately after the first ignition of the thyristors. The influence of the operating point of the solar cell array on the transient process is discussed. A sequence for optimal operations is recommended. Part I of the study (SAND 7040/1) contains a detailed description of the microcomputer based simulator that represents the output characteristics of the five commercially available types of solar cell arrays under different environmental conditions, and Part II (SAND 7040/2) describes the harmonics in the photovoltaic power system.
Methods, systems and apparatus for optimization of third harmonic current injection in a multi-phase machine
Methods, system and apparatus are provided for increasing voltage utilization in a five-phase vector controlled machine drive system that employs third harmonic current injection to increase torque and power output by a five-phase machine. To do so, a fundamental current angle of a fundamental current vector is optimized for each particular torque-speed of operating point of the five-phase machine.
Gallegos-Lopez, Gabriel
Compton harmonic resonances, stochastic instabilities, quasilinear diffusion, and collisionless damping with ultra-high intensity laser waves
The dynamics of electrons in two-dimensional, linearly or circularly polarized, ultra-high intensity (above 10{sup 18}W/cm{sup 2}) laser waves, is investigated. The Compton harmonic resonances are identified as the source of various stochastic instabilities. Both Arnold diffusion and resonance overlap are considered. The quasilinear kinetic equation, describing the evolution of the electron distribution function, is derived, and the associated collisionless damping coefficient is calculated. The implications of these new processes are considered and discussed.
Rax, J.M.
Renewable Diesel from Algal Lipids: An Integrated Baseline for Cost, Emissions, and Resource Potential from a Harmonized Model
The U.S. Department of Energy's Biomass Program has begun an initiative to obtain consistent quantitative metrics for algal biofuel production to establish an 'integrated baseline' by harmonizing and combining the Program's national resource assessment (RA), techno-economic analysis (TEA), and life-cycle analysis (LCA) models. The baseline attempts to represent a plausible near-term production scenario with freshwater microalgae growth, extraction of lipids, and conversion via hydroprocessing to produce a renewable diesel (RD) blendstock. Differences in the prior TEA and LCA models were reconciled (harmonized) and the RA model was used to prioritize and select the most favorable consortium of sites that supports production of 5 billion gallons per year of RD. Aligning the TEA and LCA models produced slightly higher costs and emissions compared to the pre-harmonized results. However, after then applying the productivities predicted by the RA model (13 g/m2/d on annual average vs. 25 g/m2/d in the original models), the integrated baseline resulted in markedly higher costs and emissions. The relationship between performance (cost and emissions) and either productivity or lipid fraction was found to be non-linear, and important implications on the TEA and LCA results were observed after introducing seasonal variability from the RA model. Increasing productivity and lipid fraction alone was insufficient to achieve cost and emission targets; however, combined with lower energy, less expensive alternative technology scenarios, emissions and costs were substantially reduced.
Davis, R.; Fishman, D.; Frank, E. D.; Wigmosta, M. S.; Aden, A.; Coleman, A. M.; Pienkos, P. T.; Skaggs, R. J.; Venteris, E. R.; Wang, M. Q.
Jordan-Schwinger map, 3D harmonic oscillator constants of motion, and classical and quantum parameters characterizing electromagnetic wave polarization
In this work we introduce a generalization of the Jauch and Rohrlich quantum Stokes operators when the arrival direction from the source is unknown {\\it a priori}. We define the generalized Stokes operators as the Jordan-Schwinger map of a triplet of harmonic oscillators with the Gell-Mann and Ne'eman SU(3) symmetry group matrices. We show that the elements of the Jordan-Schwinger map are the constants of motion of the three-dimensional isotropic harmonic oscillator. Also, we show that generalized Stokes Operators together with the Gell-Mann and Ne'eman matrices may be used to expand the polarization density matrix. By taking the expectation value of the Stokes operators in a three-mode coherent state of the electromagnetic field, we obtain the corresponding generalized classical Stokes parameters. Finally, by means of the constants of motion of the classical three-dimensional isotropic harmonic oscillator we describe the geometric properties of the polarization ellipse
R. D. Mota; M. A. Xicotencatl; V. D. Granados
The presence of astrophysical emissions between the last scattering surface and our vantage point requires us to apply a foreground mask on cosmic microwave background (CMB) sky maps, leading to large cuts around the Galactic equator and numerous holes. Since many CMB analysis, in particular on the largest angular scales, may be performed on a whole-sky map in a more straightforward and reliable manner, it is of utmost importance to develop an efficient method to fill in the masked pixels in a way compliant with the expected statistical properties and the unmasked pixels. In this Letter, we consider the Monte Carlo simulation of a constrained Gaussian field and derive it CMB anisotropy in harmonic space, where a feasible implementation is possible with good approximation. We applied our method to simulated data, which shows that our method produces a plausible whole-sky map, given the unmasked pixels, and a theoretical expectation. Subsequently, we applied our method to the Wilkinson Microwave Anisotropy Probe foreground-reduced maps and investigated the anomalous alignment between quadrupole and octupole components. From our investigation, we find that the alignment in the foreground-reduced maps is even higher than the Internal Linear Combination map. We also find that the V-band map has higher alignment than other bands, despite the expectation that the V-band map has less foreground contamination than other bands. Therefore, we find it hard to attribute the alignment to residual foregrounds. Our method will be complementary to other efforts on in-painting or reconstructing the masked CMB data, and of great use to Planck surveyor and future missions.
Kim, Jaiseung; Naselsky, Pavel [Niels Bohr Institute and Discovery Center, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Mandolesi, Nazzareno, E-mail: email@example.com [INAF/IASF, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, Istituto Nazionale di Astrofisica, via Gobetti 101, I-40129 Bologna (Italy)
Evaluation of Artifacts and Distortions of Titanium Applicators on 3.0-Tesla MRI: Feasibility of Titanium Applicators in MRI-Guided Brachytherapy for Gynecological Cancer
Purpose: The aim of this study was to characterize the levels of artifacts and distortions of titanium applicators on 3.0-Tesla magnetic resonance imaging (MRI). Methods and Materials: Fletcher-Suit-Delclos-style tandem and ovoids (T and O) and tandem and ring applicator (T and R) were examined. The quality assurance (QA) phantoms for each applicator were designed and filled with copper sulphate solution (1.5 g/l). The artifacts were quantified with the registration of corresponding computed tomography (CT) images. A favorable MR sequence was searched in terms of artifacts. Using the sequence, the artifacts were determined. The geometric distortions induced by the applicators were quantified through each registration of CT and MRI without applicators. The artifacts of T and O were also evaluated on in vivo MRI datasets of 5 patients. Results: T1-weighted MRI with 1-mm slice thickness was found as a favorable MR sequence. Applying the sequence, the artifacts at the tandem tip of T and O and T and R were determined as 1.5 {+-} 0.5 mm in a superior direction in phantom studies. In the ovoids of T and O, we found artifacts less than 1.5 {+-} 0.5 mm. The artifacts of a T and O tandem in vivo were found as less than 2.6 {+-} 1.3 mm on T1-weighted MRI, whereas less than 6.9 {+-} 3.4 mm on T2-weighted MRI. No more than 1.2 {+-} 0.6 mm (3.0 {+-} 1.5 mm) of distortions, due to a titanium applicator, were measured on T1-weighted MRI (T2-). Conclusion: In 3.0-Tesla MRI, we found the artifact widths at the tip of tandem were less than 1.5 {+-} 0.5 mm for both T and O and T and R when using T1-weighted MRI in phantom studies. However, exclusive 3.0-Tesla MRI-guided brachytherapy planning with a titanium applicator should be cautiously implemented.
Kim, Yusung, E-mail: email@example.com [Department of Radiation Oncology, University of Iowa, Iowa City, IA (United States); Muruganandham, Manickam; Modrick, Joseph M.; Bayouth, John E. [Department of Radiation Oncology, University of Iowa, Iowa City, IA (United States)
Explicit formulas for generalized harmonic perturbations of the infinite quantum well with an application to Mathieu equations
We obtain explicit formulas for perturbative corrections of the infinite quantum well model. The formulas we obtain are based on a class of matrix elements that we construct by means of two-parameter ladder operators associated with the infinite quantum well system. Our approach can be used to construct solutions to Schroedinger-type equations that involve generalized harmonic perturbations of their potentials, such as cosine powers, Fourier series, and more general functions. As a particular case, we obtain characteristic values for odd periodic solutions of the Mathieu equation.
Garcia-Ravelo, J.; Trujillo, A. L. [Escuela Superior de Fisica y Matematicas, Instituto Politecnico Nacional, Unidad Profesional Adolfo Lopez Mateos, Zacatenco, 07738 Mexico D.F. (Mexico); Schulze-Halberg, A. [Department of Mathematics and Actuarial Science, Indiana University Northwest, 3400 Broadway, Gary, Indiana 46408 (United States)
The quantum harmonic oscillator on the sphere and the hyperbolic plane: {kappa}-dependent formalism, polar coordinates, and hypergeometric functions
A nonlinear model representing the quantum harmonic oscillator on the sphere and the hyperbolic plane is solved in polar coordinates (r,{phi}) by making use of a curvature-dependent formalism. The curvature {kappa} is considered as a parameter and then the radial Schroedinger equation becomes a {kappa}-dependent Gauss hypergeometric equation. The energy spectrum and the wave functions are exactly obtained in both the sphere S{sup 2} ({kappa}>0) and the hyperbolic plane H{sup 2} ({kappa}<0). A comparative study between the spherical and the hyperbolic quantum results is presented.
Carinena, Jose F.; Ranada, Manuel F.; Santander, Mariano [Departmento de Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza (Spain); Departamento de Fisica Teorica, Facultad de Ciencias, Universidad de Valladolid, 47011 Valladolid (Spain)
Effects of distortion of the intercluster motion in {sup 2}H, {sup 3}He, {sup 3}H, {sup 6}Li, and {sup 9}Be on Trojan horse applications
Deuteron induced quasifree scattering and reactions have been extensively investigated in the past few decades as well as {sup 6}Li, {sup 3}H, {sup 3}He, and {sup 9}Be induced reactions. This was done not only for the investigation of nuclear structure and reaction mechanisms but also for important astrophysical applications (Trojan horse method). In particular the widths of the spectator momentum distributions in several nuclei, which have been used as Trojan horses, have been obtained as a function of the transferred momentum. Applications of Trojan horse method will also be discussed because the momentum distribution of the spectator particle inside the nucleus is a important input for this method. This gives hints on distortion effects at low energies important for nuclear astrophysics.
Pizzone, R. G.; Spitaleri, C.; La Cognata, M.; Lamia, L.; Romano, S. [Laboratori Nazionali del Sud-INFN, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l'Ingegneria, Universita di Catania, Catania (Italy); Mukhamedzhanov, A. M. [Cyclotron Institute, Texas A and M University, College Station (United States); Blokhintsev, L. D. [Moscow State University, Moscow (Russian Federation); Bertulani, C. A. [Physics Department, Texas A and M University, Commerce (United States); Irgaziev, B. F. [GIK Institute of Engineering Sciences and Technology, Topi, District Swabi, N. W. F. P. (Pakistan)
First-order thermal correction to the quadratic response tensor and rate for second harmonic plasma emission
Three-wave interactions in plasmas are described, in the framework of kinetic theory, by the quadratic response tensor (QRT). The cold-plasma QRT is a common approximation for interactions between three fast waves. Here, the first-order thermal correction (FOTC) to the cold-plasma QRT is derived for interactions between three fast waves in a warm unmagnetized collisionless plasma, whose particles have an arbitrary isotropic distribution function. The FOTC to the cold-plasma QRT is shown to depend on the second moment of the distribution function, the phase speeds of the waves, and the interaction geometry. Previous calculations of the rate for second harmonic plasma emission (via Langmuir-wave coalescence) assume the cold-plasma QRT. The FOTC to the cold-plasma QRT is used here to calculate the FOTC to the second harmonic emission rate, and its importance is assessed in various physical situations. The FOTC significantly increases the rate when the ratio of the Langmuir phase speed to the electron thermal speed is less than about 3.
Layden, B.; Cairns, Iver H.; Robinson, P. A. [School of Physics, University of Sydney, Sydney, New South Wales 2006 (Australia); Percival, D. J. [Defence Science and Technology Organisation, P.O. Box 1500, Edinburgh, South Australia 5111 (Australia)
High-temperature thermodynamics of strongly interacting s-wave and p-wave Fermi gases in a harmonic trap
We theoretically investigate the high-temperature thermodynamics of a strongly interacting trapped Fermi gas near either s-wave or p-wave Feshbach resonances, using a second-order quantum virial expansion. The second virial coefficient is calculated based on the energy spectrum of two interacting fermions in a harmonic trap. We consider both isotropic and anisotropic harmonic potentials. For the two-fermion interaction, either s-wave or p-wave, we use a pseudopotential parametrized by a scattering length and an effective range. This turns out to be the simplest way of encoding the energy dependence of the low-energy scattering amplitude or phase shift. This treatment of the pseudopotential can be easily generalized to higher partial-wave interactions. We discuss how the second virial coefficient and thermodynamics are affected by the existence of these finite-range interaction effects. The virial expansion result for a strongly interacting s-wave Fermi gas has already been proved very useful. In the case of p-wave interactions, our results for the high-temperature equation of state are applicable to future high-precision thermodynamic measurements for a spin-polarized Fermi gas near a p-wave Feshbach resonance.
Peng Shiguo [Department of Physics, Tsinghua University, Beijing, 100084 (China); Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122 (Australia); Li Shiqun [Department of Physics, Tsinghua University, Beijing, 100084 (China); Drummond, Peter D.; Liu Xiaji [Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology, Melbourne 3122 (Australia)
Path Integral Approach to the Calculation of Reaction Rates for a Reaction Coordinate Coupled to a Dual Harmonic Bath
We present a new method for the numerical calculation of canonical reaction rate constants in complex molecular systems, which is based on a path integral formulation of the flux-flux correlation function. Central is the partitioning of the total system into a relevant part coupled to a dual bath. The latter consists of two parts: First, a set of strongly coupled harmonic modes, describing, for example, intramolecular degrees of freedom. They are treated on the basis of a reaction surface Hamiltonian approach. Second, a set of bath modes mimicking an unspecific environment modeled by means of a continuous spectral density. After deriving a set of general equations expressing the canonical rate constant in terms of appropriate influence functionals, several approximations are introduced to provide an efficient numerical implementation. Results for an initial application to the H-transfer in 6-Aminofulvene-1-aldimine are discussed.
Yang, Yonggang
Analytical transformed harmonic oscillator basis for three-body nuclei of astrophysical interest: Application to 6He
Recently, a square-integrable discrete basis, obtained performing a simple analytical local scale transformation to the harmonic oscillator basis, has been proposed and successfully applied to study the properties of two-body systems. Here, the method is generalized to study three-body systems. To test the goodness of the formalism and establish its applicability and limitations, the capture reaction rate for the nucleosynthesis of the Borromean nucleus 6He (4He + n + n) is addressed. Results are compared with previous publications and with calculations based on actual three-body continuum wave functions, which can be generated for this simple case. The obtained results encourage the application to other Borromean nuclei of astrophysical interest such as 9Be and 12C, for which actual three-body continuum calculations are very involved.
J. Casal; M. Rodr�guez-Gallardo; J. M. Arias
Harmonic Responses in 2DEG AlGaAs/GaAs HEMT Devices Due to Plasma Wave Interaction
Plasma waves are oscillations of electron density in time and space, and in deep submicron field effect transistors, typical plasma frequencies, omega{sub p}, lie in the terahertz range and do not involve any quantum transitions. Hence, using plasma wave excitation for detection and/or generation of THz oscillations is a very promising approach. In this paper, the investigation of plasma wave interaction between the plasma waves propagating in a short-channel High-Electron-Mobility Transistor (HEMT) and the radiated electromagnetic waves was carried out. Experimentally, we have demonstrated the detection of the terahertz (THz) radiation by an AlGaAs/GaAs HEMT up to third harmonic at room temperature and their resonant responses show very good agreement with the calculated results.
Hashim, A. M.; Alias, Q. I. [Faculty of Electrical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Kasai, S.; Hasegawa, H. [Research Center for Integrated Quantum Electronics, Hokkaido University North 12 West 8, Sapporo 060-8628 (Japan)
A new uniform parameterization and invariant 3D spherical harmonic shape descriptors for shape analysis of the heart's left ventricle - A pilot study
A new approach for uniform parameterization and rotation invariant global description of 3D triangular surface meshes of objects with a spherical topology is presented. It consists of two steps. First, an initial mapping based on a heat conduction model ... Keywords: Left ventricle, Myocardial scintigraphy, Rotation invariant 3D shape descriptors, Spherical harmonic model, Uniform parameterization
A. Ben Abdallah; F. Ghorbel; K. Chatti; H. Essabbah; M. H. Bedoui
Measurements and modeling of laser irradiance in the high-power third-harmonic Nova focus: Volume B, Data book. Volume 2
Applications of an electronic transformer in a power distribution system
In electrical power distribution and power electronic applications, a transformer is an indispensable component which performs many functions. At its operating frequency (60/50 Hz), it is one of the most bulky and expensive components. The concept of the electronic transformer introduced previously has shown considerable reduction in size, weight, and volume by operating at a higher frequency. In this dissertation, the concept of the electronic transformer is further extended to the auto-connected phase-shifting type to reduce harmonics generated by nonlinear loads. It is shown that with the addition of primary side and secondary side AC/AC converters achieves phase-shifting. With the addition of converters, magnetic components are operated at a higher frequency to yield a smaller size and weight. Two types of auto-connected electronic transformer configurations are explored. In the first configuration, the secondary converter is eliminated and the output is suitable for rectifier type loads such as adjustable speed drives. In the second configuration, the secondary converter is added to obtain a sinusoidal phase-shifted AC output voltage. This approach is applicable in general applications. With the proposed approaches, the th and 7th harmonic in utility line currents, generated by two sets of nonlinear loads, are subtracted within the electronic transformer, thereby reducing the total harmonic distortion (THD) of the line current. The analysis and simulation results are presented. In the second part of the dissertation, the electronic transformer concept is applied to a telecommunication power supply (-48 VDC) system. The proposed approach consists of a matrix converter to convert the low frequency three-phase input AC utility to a high frequency AC output without a DC-link. The output of the matrix converter is then processed via a high frequency isolation transformer to produce -48 VDC. Digital control of the system ensures that the output voltage is regulated and the input currents are of high quality, devoid of low frequency harmonics and at near unity input power factor under varying load conditions. Due to the absence of DC-link electrolytic capacitors, the power density of the proposed rectifier is shown to be higher. Analysis, design example and experimental results are presented from a three-phase 208 V, 1.5 kW laboratory prototype converter.
Ratanapanachote, Somnida
Lattice distortions in layered type arsenides LnTAs{sub 2} (Ln=La-Nd, Sm, Gd, Tb; T=Ag, Au): Crystal structures, electronic and magnetic properties
The lanthanide coinage-metal diarsenides LnTAs{sub 2} (Ln=La, Ce-Nd, Sm; T=Ag, Au) have been reinvestigated and their structures have been refined from single crystal X-ray data. Two different distortion variants of the HfCuSi{sub 2} type are found: PrAgAs{sub 2}, NdAgAs{sub 2}, SmAgAs{sub 2}, GdAgAs{sub 2}, TbAgAs{sub 2}, NdAuAs{sub 2} and SmAuAs{sub 2} crystallize as twofold superstructures in space group Pmcn with the As atoms of their planar layers forming zigzag chains, whereas LaAgAs{sub 2}, CeAgAs{sub 2} and PrAuAs{sub 2} adopt a fourfold superstructure (space group Pmca) with cis-trans chains of As atoms. The respective atomic positions can be derived from the HfCuSi{sub 2} type by group-subgroup relations. The compounds with zigzag chains of As atoms exhibit metallic behaviour while those with cis-trans chains are semiconducting as measured on powder pellets. The majority of the compounds including 4f elements show antiferromagnetic ordering at T{sub N}<20 K. - Text3: Zigzig vs. cis-trans.
Rutzinger, D.; Bartsch, C. [Anorganische Chemie, Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, D-01062 Dresden (Germany); Doerr, M. [Institut fuer Festkoerperphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Rosner, H. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Str. 40, D-01187 Dresden (Germany); Neu, V. [IFW Dresden, Institut fuer metallische Werkstoffe, Helmholtzstr. 20, D-01069 Dresden (Germany); Doert, Th., E-mail: firstname.lastname@example.com [Anorganische Chemie, Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, D-01062 Dresden (Germany); Ruck, M. [Anorganische Chemie, Fachrichtung Chemie und Lebensmittelchemie, Technische Universitaet Dresden, D-01062 Dresden (Germany)
Distortion Representation of Forecast Errors
Forecast error is decomposed into three components, termed displacement error, amplitude error, mid residual error, respectively. Displacement error measures how much of the forecast error can be accounted for by moving the forecast to best fit ...
Ross N. Hoffman; Zheng Liu; Jean-Francois Louis; Christopher Grassoti
Influence of Cooling on Distortion
Table 11 Factors that influence the cooling intensity of liquid quenchants...the vapor pressure is, the more difficult the
Greenland has a major influence on the atmospheric circulation of the North Atlantic�western European region, dictating the location and strength of mesoscale weather systems around the coastal seas of Greenland and directly influencing synoptic-...
I. A. Renfrew; G. N. Petersen; S. Outten; D. Sproson; G. W. K. Moore; C. Hay; T. Ohigashi; S. Zhang; J. E. Kristj�nsson; I. F�re; H. �lafsson; S. L. Gray; E. A. Irvine; K. Bovis; P. R. A. Brown; R. Swinbank; T. Haine; A. Lawrence; R. S. Pickart; M. Shapiro; A. Woolley
High Harmonic Fast Wave Heating Efficiency Enhancement and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive CD are being developed on the National Spherical Torus Experiment M. Ono et al., Nucl. Fusion 41, 1435 2001 for supporting startup and sustainment of the spherical torus plasma. Considerable enhancement of the core heating efficiency from 44% to 65% has been obtained for CD phasing of the antenna strap-to-strap = 90 , k= 8 m 1 by increasing the magnetic field from 4.5 to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation nonsetBk 2 / away from the antenna face and wall, and hence reducing the propagating surface wave fields. Radio frequency RF waves propagating close to the wall at lower B and k can enhance power losses from both the parametric decay instability PDI and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations.
Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Phillips, Cynthia [Princeton Plasma Physics Laboratory (PPPL); Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Valeo, Dr Ernest [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL); Jaeger, Erwin Frederick [ORNL; Ryan, Philip Michael [ORNL; Wilgen, John B [ORNL; Yuh, H. [Nova Photonics; Levinton, F. [Fusion Physics and Technology; Sabbagh, S. A. [Columbia University; Tritz, K. [Johns Hopkins University; Parker, J. [Cornell University; Bonoli, P. [Massachusetts Institute of Technology (MIT); Harvey, R. W. [CompX, Del Mar, CA
High Harmonic Fast Wave Heating Efficiency Enhancemen and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive (CD) are being developed on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 41, 1435 (2001)] for supporting startup and sustainment of the ST plasma. Considerable enhancement of the core heating efficiency (?) from 44% to 65% has been obtained for CD phasing of the antenna (strap-to-strap ? = -90o, k? = -8 m-1) by increasing the magnetic field from 4.5 kG to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation (nonset ? ??� k|| 2/w) away from the antenna face and wall, and hence reducing the propagating surface wave fields. RF waves propagating close to the wall at lower B? and k|| can enhance power losses from both the parametric decay instability (PDI) and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations
J. Hosea, R. E. Bell, B.P. LeBlanc, C.K. Phillips, G. Taylor, E. Valeo, J.R. Wilson, E.F. Jaeger, P.M. Ryan, J. Wilgen, H. Yuh, F. Levinton, S. Sabbagh, K. Tritz, J. Parker, P.T. Bonoli, R. Harvey, and the NSTX Team
Minimum variational principles for time-harmonic waves in a dissipative medium and associated variational principles of Hashin--Shtrikman type
Minimization variational principles for linear elastodynamic, acoustic, or electromagnetic time-harmonic waves in dissipative media were obtained by Milton, Seppecher and Bouchitt\\'e generalizing the quasistatic variational principles of Cherkaev and Gibiansky. Here a further generalization is made to allow for a much wider variety of boundary conditions, and in particular Dirichlet and Neumann boundary conditions. In addition minimization or maximization principles of the Hashin-Shtrikman type, incorporating "polarization fields", are developed.
Graeme W. Milton; John R. Willis
Magnetically Controlled Reactor Shrinks Power Quality Costs and...
ensures less than 2-3% main harmonic distortion even without special filters. Transformer-like construction ensures reliable operation. MCR's increase power quality through...
Energy saving controller for fluorescent lamps.
??Although fluorescent lamp is a very efficient lighting device in daily life, still the high harmonic distortion and low power factor cause unnecessary energy consumption.� (more)
Cheong, Zhi Xiong
Quantum Harmonic Black Holes
Inspired by the recent conjecture that black holes are condensates (of gravitons), we investigate a simple model for the black hole degrees of freedom that is consistent both from the point of view of Quantum mechanics and of General Relativity. Since the two perspectives should converge for small, Planck size, black holes, we expect our construction is useful for understanding the physics of microscopic, quantum black holes.
Casadio, R
Harmonic parameterization by electrostatics
In this article, we introduce a method to apply ideas from electrostatics to parameterize the open space around an object. By simulating the object as a virtually charged conductor, we can define an object-centric coordinate system which we call Electric ... Keywords: Coordinates, cloth control, parameterization
He Wang, Kirill A. Sidorov, Peter Sandilands, Taku Komura
Technical Study Addresses a Key Challenge to Harmonizing U.S. and International PV Module Standards (Fact Sheet)
NREL builds community and industry support by addressing concerns voiced by key standards organizations. Photovoltaic (PV) manufacturers in the United States test the safety of their products using standards developed through consensus processes. Because U.S. PV module safety standards are not aligned with international standards, manufacturers must test their modules twice - and sometimes maintain separate product lines. By meeting with standards organizations such as the Solar ABCs and Underwriters Laboratories (UL), National Renewable Energy Laboratory (NREL) leaders have worked to identify different stakeholders priorities and concerns. UL, specifically, has expressed concern that the international standards do not address all possible risks. For example, new encapsulant materials could soften at high temperatures and frameless modules could slide apart, exposing live electrical parts or allowing glass to fall on a person below. The deformation of a solid material under the influence of mechanical stresses is known as 'creep.' Current module qualification tests are limited to 85 C, whereas modules can, for short times, reach 105 C outdoors. In response to UL's concern, NREL designed and executed an experiment to compare on-sun and accelerated rates of creep for modules fabricated with various encapsulants, including some that have low melting points. Objectives were to (1) evaluate the potential for creep in outdoor exposure, (2) provide guidance on the risks and design needs with thermoplastic materials, and (3) provide a basis for modifying standards to account for materials with potential to creep. The study tested experimental materials with eight representative encapsulants in both outdoor and indoor (chamber) exposure. The study found that modules with materials that were expected to creep did so in the indoor exposure, but not in most outdoor environments and mounting configurations. The results provide a basis for defining an accelerated test needed to give confidence that the modules will not slide apart on hot days. The proposal for IEC 61730 Part 1 exposes modules for 200 hours to a temperature between 105 C and 110 C. NREL is collaborating with UL representatives, and U.S. and international standards appear to be closer to harmonization.
Coherent terahertz radiation from high-harmonic component of modulated free-electron beam in a tapered two-asymmetric grating structure
Based on the mechanism of incoherent diffraction radiation excited by an electron bunch in a waveguide with periodic structure, this paper presents the concept of coherent terahertz (THz) radiation from the high-harmonic component of a modulated free-electron beam in a tapered two-asymmetric grating structure. The results show that in this mechanism 0.43 THz radiation can be generated with 10 A/cm{sup 2} current density, and the efficiency can reach 0.5%. Because of the low required current density and relative high efficiency, this concept shows the application potential for electron-beam-driven terahertz sources.
Zhang Yaxin; Zhou Yucong; Dong Liang; Liu Shenggang [Terahertz Science and Technology Research Center, University of Electronic Science and Technology of China, Chengdu 610054 (China)
Chains of centered metal clusters with a novel range of distortions: Pr[sub 3]I[sub 3]Ru, Y[sub 3]I[sub 3]Ru, and Y[sub 3]I[sub 3]Ir
The phases R[sub 3]I[sub 3]Ru (R = La, Pr, Gd, Y, Er) and R[sub 3]I[sub 3]Ir (R = Gd, Y) are obtained from the reactions of R, RI[sub 3], and Ru or Ir for 3-4 weeks in sealed Ta tubing at 850-975C, depending on the system. The title phases have been characterized by single-crystal X-ray means at room temperature. The first phase contains quasi-infinite double chains of edge-sharing Pr[sub 6](Ru) octahedra that are sheathed and interbridged by iodine. An evidently continuous distortion of these chains parallels the a/b axial ratio (in the order listed in the first sentence) such that metal octahedra are no longer obvious in Y[sub 3]I[sub 3]Ir; rather chains of trans-edge-sharing square pyramidal Y[sub 4]Ir units bonded base-to-base are more apt. Increased R-R, R-interstitial, and interstitial-interstitial bonding appears to parallel the degree of distortion. Magnetic data for La[sub 3]I[sub 3]Ru and Pr[sub 3]I[sub 3]Ru and the results of extended Hueckel band calculations on Pr[sub 3]I[sub 3]Ru are reported. Polar covalent Pr-Ru interactions and at least a quasi-closed shell configuration are emphasized by the latter.
Payne, M.W.; Dorhout, P.K.; Kim, Sungjin; Hughbanks, T.R.; Corbett, J.D. (Iowa State Univ., Ames (United States) Texas A and M Univ., College Station (United States))
Behavior of two capstone 30kW microturbines operating in parallel with impedance between them
Average of 96 Samples: Va = 3.52% THD, 270.0 Volts Vb =3.49% THD, 270.2 Volts Vc =3.51% THD, 271.6 Volts Percent of Fundamental Va Avg Vb Avg
Yinger, Robert J.
Study of interfacial charge-transfer complex on TiO{sub 2} particles in aqueous suspension by second-harmonic generation
Titanium dioxide (TiO{sub 2}) is a wide band-gap semiconductor having two common crystal forms: rutile and anatase. Due to its high physical and chemical stability, it is extensively studied as a photocatalyst for photolysis of water, and for oxidative photomineralization of organic pollutants in wastewater, aimed at harvesting solar energy. The authors report the first direct observation of an interfacial charge-transfer complex using second-harmonic spectroscopy. The second-harmonic spectrum of catechol adsorbed on 0.4 micron-sized TiO{sub 2} (anatase) colloidal particles in aqueous suspension reveals a charge-transfer band centered at 2.72 eV (456 nm). In addition, the adsorption isotherm of catechol on the colloidal TiO{sub 2} suspension was obtained and gave an excellent fit to the Langmuir adsorption model. From this, the authors infer the free energy of the adsorption to be {Delta}G{degree} = {minus}6.8 kcal/mol.
Liu, Y.; Dadap, J.I.; Zimdars, D.; Eisenthal, K.B. [Columbia Univ., New York, NY (United States). Dept. of Chemistry
Disentangling flow and nonflow correlations via Bayesian unfolding of the event-by-event distributions of harmonic coefficients in ultrarelativistic heavy-ion collisions
The performance of the Bayesian unfolding method in extracting the event-by-event (EbyE) distributions of harmonic flow coefficients v_n is investigated using a toy model simulation, as well as simulations based on the HIJING and AMPT models. The unfolding method is shown to recover the input v_2-v_4 distributions for multiplicities similar to those observed in Pb+Pb collisions at the LHC. The effects of the nonflow are evaluated using HIJING simulation with and without a flow afterburner. The probability distribution of v_n resulting only from nonflow in HIJING is nearly a Gaussian and can be largely suppressed in the data-driven unfolding method used by the ATLAS Collaboration. The residual nonflow effects have no appreciable impact on the v_3 distributions, but are found to affect the tails of the v_2 and v_4 distributions; these effects manifest as a small simultaneous change in the mean and standard deviation of the $v_n$ distributions. For the AMPT model, which contains both flow fluctuations and nonflow effects, the reduced shape of the extracted v_n distributions is found to be independent of pT in the low pT region, similar to what is observed in the ATLAS data. The prospect of using the EbyE distribution of the harmonic spectrum aided by the unfolding technique as a general tool to study azimuthal correlations in high energy collisions is also discussed.
Jiangyong Jia; Soumya Mohapatra
PROJECT SHEET SUBCOMMITTEE: Food Residues Subcommittee PROJECT TITLE: Expansion, Development and Harmonization of Crop Groups With Specified Representative Crops for Field Crop Residues Studies
GOAL/OBJECTIVE: To further develop and implement Crop groups utilized by NAFTA and based on representative commodities to foster worldwide harmonization of Crop groups and commodity terminology which will help remove trade irritants due to differences in commodity tolerance levels or MRLs for minor and specialty crops. PROJECT DESCRIPTION/PROCEDURE The Chairperson (Hong Chen) of the International Crop Grouping Consulting Committee (ICGCC) forwards the Symposium proposal for a particular crop group to the appropriate workgroup of the ICGCC via emails and requests the workgroup members to provide input on crop information and maximum residue limit (MRL) information (includes U.S., NAFTA, Codex and EU) on the commodities. Growers and commodity experts also provide valuable input on commodities. International members provide specific information on the commodities grown in their countries and regions which provides perspectives on harmonization approaches. Based on the input, the ICGCC Chairperson will prepare commodity monographs, divide subgroups, select representative crops and draft new crop group petitions. The draft petitions will be forwarded to the workgroup for review and comments before being finalized, and the
High-order optical harmonic generation as a process of single atom interaction with sub-relativistic single- and multicolor laser fields
We present a non-perturbative theory of a single atom interaction with the multicolor laser field. The theory is based on the use of exact mathematical solutions of the boundary value problem for 'an atom in the external field', as a result the case of arbitrary orientation of atomic angular momentum and electromagnetic wave polarization vector can be described in the consistent mathematical form. We also present the results of numerical simulations on silver and argon atoms interaction with single-and two-color laser fields formed by fundamental frequency and second harmonic of Ti:Sapphire laser. The results of numerical calculations show that the efficiency of high-order harmonic generation (HHG) depends strongly on the laser field parameters (especially on the orientation of polarization vectors and chirp of the two-color laser field components). We have demonstrated the saturation of the cut-off frequency in the laser fields of near-atomic strength and investigated the impact of the field phase in the case of ultrashort laser pulses.
Andreev, A. V.; Stremoukhov, S. Yu.; Shoutova, O. A. [M. V. Lomonosov Moscow State University, physical department, 119991 Leninskie Gory, 1, build. 2, Moscow (Russian Federation)
Cerenkov-type phase-matched second-harmonic emission from GaAs/AlGaAs quantum-cascade lasers
Second-harmonic (SH) emission in the form of Cerenkov-type phase-matched radiation has been measured for quantum-cascade lasers (QCLs) with built-in nonlinearities. The QCLs operate at 10.9 {mu}m wavelength and, due to material dispersion, show a high collinear phase mismatch, resulting in low SH external conversion efficiencies on the order of 2 {mu}W/W{sup 2}. Due to our waveguide design, we were able to couple out and measure the generated SH light in the form of Cerenkov-type phase-matched radiation from the substrate of the device. The SH power collected from the Cerenkov beam leads to an increased external conversion efficiency of {approx}50 {mu}W/W{sup 2}.
Austerer, M.; Detz, H.; Schartner, S.; Nobile, M.; Schrenk, W.; Andrews, A. M.; Klang, P. [Center for Micro- and Nanostructures, TU Vienna, Floragasse 7, A-1040 Vienna (Austria); Strasser, G. [Departments of Electrical Engineering and Physics, SUNY at Buffalo, New York 14260 (United States)
Comparison of bounce-averaged quasilinear theory with charge exchange measurements during minority fundamental and majority second harmonic ICRF heating in PLT
Previous studies in PLT using charge-exchange, edge probe, and fusion product diagnostics all indicate that ICRF tends to produce energetic trapped particles whose banana tips are near the resonance layer. A bounce-averaged quasilinear operator which predicts this ''resonance localization'' has been implemented in a Fokker-Planck code in order to make detailed comparisons with measurements. Good agreement is found with data from the horizontally-scanning, mass-resolving, charge-exchange analyzer, although the RF power profile seems to be broader than expected. We have recently observed a deuterium tail during hydrogen minority heating. The shape of this tail and its scaling with RF power agree well with the quasilinear theory. These measurements indicate that as much as 30% of the central RF power goes into direct second harmonic deuterium heating.
Hammett, G.W.; Colestock, P.L.; Gammel, G.; Goldston, R.J.; Hosea, J.C.; Hwang, D.Q.; Kaita, R.; Ono, M.; Roquemore, L.; Wilson, J.R.
Preparation, characterization, and second-harmonic generation of a Langmuir-Blodgett film based on a rare-earth coordination compound
The rare-earth coordination compound (E)-N-hexadecyl-4-(2-(4-(dimethylamino)phenyl)-ethenyl)pyridinium tetrakis(1-phenyl-3-methyl-4-benzoyl-5-pyrazolonato)dysprosium(III) was synthesized. The LB films were prepared and characterized by UV-vis, IR, X-ray photoelectron spectroscopy, and low-angle X-ray diffraction. High-quality LB films up to 50 layers on the hydrophilic substrates of quartz, calcium fluoride, and glass were obtained. From the second-harmonic generation measurement, second-order molecular hyperpolarizability {beta} of the dysprosium complex was estimated to be about (6.6-9.3) x 10{sup {minus}28} esu. 14 refs., 6 figs., 1 tab.
Wang, K.Z.; Huang, C.H.; Xu, G.X.; Zhao, X.S.; Xie, X.M.; Wu, N.Z. [Peking Univ., Beijing (China); Xu, Y.; Liu, Y.Q.; Zhu, D.B. [Institute of Chemistry, Beijing (China)
Studies of azimuthal anisotropy harmonics in ultra-central PbPb collisions at sqrt(s[NN]) = 2.76 TeV
Azimuthal dihadron correlations of charged particles have been measured in PbPb collisions at sqrt(s[NN]) = 2.76 TeV by the CMS collaboration, using data from the 2011 LHC heavy-ion run. The data set includes a sample of ultra-central (0-0.2% centrality) PbPb events collected using a trigger based on total transverse energy in the hadron forward calorimeters and the total multiplicity of pixel clusters in the silicon pixel tracker. A total of about 1.8 million ultra-central events were recorded, corresponding to an integrated luminosity of 120 inverse microbarns. The observed correlations in ultra-central PbPb events are expected to be particularly sensitive to initial-state fluctuations. The single-particle anisotropy Fourier harmonics, from v[2] to v[6], are extracted as a function of particle transverse momentum. At higher transverse momentum, the v[2] harmonic becomes significantly smaller than the higher-order v[n] (n greater than or equal to 3). The pt-averaged v[2] and v[3] are found to be equal within 2%, while higher-order v[n] decrease as n increases. The breakdown of factorization of dihadron correlations into single-particle azimuthal anisotropies is observed. This effect is found to be most prominent in the ultra-central PbPb collisions, where the initial-state fluctuations play a dominant role. A comparison of the factorization data to hydrodynamic predictions with event-by-event fluctuating initial conditions is also presented.
CMS Collaboration
Sulfur K-Edge XAS and DFT Calculations on [Fe4S4]2+Clusters: Effects of H-bonding and Structural Distortion on Covalency and SpinTopology
Sulfur K-edge X-ray absorption spectroscopy of a hydrogen-bonded elongated [Fe{sub 4}S{sub 4}]{sup 2+} cube is reported. The data show that this synthetic cube is less covalent than a normal compressed cube with no hydrogen bonding. DFT calculations reveal that the observed difference in electronic structure has significant contributions from both the cluster distortion and from hydrogen bonding. The elongated and compressed Fe{sub 4}S{sub 4} structures are found to have different spin topologies (i.e., orientation of the delocalized Fe{sub 2}S{sub 2} subclusters which are antiferromagnetically coupled to each other). It is suggested that the H-bonding interaction with the counterion does not contribute to the cluster elongation. A magneto-structural correlation is developed for the Fe{sub 4}S{sub 4} cube that is used to identify the redoxactive Fe{sub 2}S{sub 2} subclusters in active sites of HiPIP and ferredoxin proteins involving these clusters.
Dey, A.; Roche, C.L.; Walters, M.A.; Hodgson, K.O.; B., Hedman; Solomon, E.I.; /Stanford U., Chem. Dept. /SLAC, SSRL
Harmonization of Land-Use Scenarios for the Period 1500-2100: 600 Years of Global Gridded Annual Land-Use Transitions, Wood Harvest, and Resulting Secondary Lands
In preparation for the fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC), the international community is developing new advanced Earth System Models (ESM) to assess the combined effects of human activities (e.g. land use and fossil fuel emissions) on the carbon-climate system. In addition, four Representative Concentration Pathway (RCP) scenarios of the future (2005-2100) are being provided by four Integrated Assessment Model (IAM) teams to be used as input to the ESMs for future carbon-climate projections (Moss et al., 2010). The diversity of approaches and requirements among IAMs and ESMs for tracking land-use change, along with the dependence of model projections on land-use history, presents a challenge for effectively passing data between these communities and for smoothly transitioning from the historical estimates to future projections. Here, a harmonized set of land-use scenarios are presented that smoothly connects historical reconstructions of land use with future projections, in the format required by ESMs.
Hurtt, George; Chini, Louise Parsons; Frolking, Steve; Betts, Richard; Feddema, Johannes; Fischer, Gavin M.; Fisk, J.P.; Hibbard, Kathleen A.; Houghton, R. A.; Janetos, Anthony C.; Jones, C.; Kindermann, G.; Kinoshita, Tsuguki; Goldeweijk, Kees K.; Riahi, Keywan; Shevliakova, Elena; Smith, Steven J.; Stehfest, Eike; Thomson, Allison M.; Thornton, P.; Van Vuuren, Detlef; Wang, Y.
Nanograting-based compact VUV spectrometer and beam profiler for in-situ characterization of high-order harmonic generation light sources
A compact, versatile device for VUV beam characterization is presented. It combines the functionalities of a VUV spectrometer and a VUV beam profiler in one unit and is entirely supported by a standard DN200 CF flange. The spectrometer employs a silicon nitride transmission nanograting in combination with a micro-channel plate based imaging detector. This enables the simultaneous recording of wavelengths ranging from 10 nm to 80 nm with a resolution of 0.25 nm to 0.13 nm. Spatial beam profiles with diameters up to 10 mm are imaged with 0.1 mm resolution. The setup is equipped with an in-vacuum translation stage that allows for in situ switching between the spectrometer and beam profiler modes and for moving the setup out of the beam. The simple, robust design of the device is well suited for non-intrusive routine characterization of emerging laboratory- and accelerator-based VUV light sources. Operation of the device is demonstrated by characterizing the output of a femtosecond high-order harmonic generation light source.
Kornilov, Oleg; Wilcox, Russell; Gessner, Oliver
Correction of Doi-Edwards' Green Function for a Chain in a Harmonic Potential and its Implication for the Stress-Optical Rule
We provide a corrected Green's function for a polymer chain trapped in a two-dimensional anisotropic harmonic potential with a fixed boundary condition. This Green's function is a modified version of what Doi and Edwards first derived to describe the polymer chain confined in the tube-like domain of surrounding entangled polymers [J. Chem. Soc. Farad. Trans. II 74 (1978) 1802]. In contradiction to the results found by Ianniruberto and Marrucci (IM) when applying the Doi-Edwards Green function [J. Non-Newtonian Fluid Mech. 79 (1998) 225], we find that the stress-optical rule is violated for any tube potential either circular or elliptic if the corrected Green's function is used. The violation is due to the presence of the virtual springs to confine the chain in the tube rather than the anisotropy of the confinement potential. On the other hand, Doi and Edwards used their Green's function only for estimation of the monomer density along the primitive path where we find just a small correction. Since they did not use it for rheological calculations, the stress-optic rule appears to be safe for the Doi-Edwards model.
Jay D. Schieber; Tsutomu Indei
Impact of Nonlinear Loads on Motor Generator Sets
Using backup generators with loads that create high harmonics can cause power quality problems. This report describes how to calculate voltage distortion based on the different impedance characteristics of a generator and the harmonic current characteristics of loads and discusses options for reducing the harmonics and mitigating their impact.
Price distortions in the commodity futures markets
Speculation is not monolithic; it comes in many forms. A certain level of speculation is required for commodity futures markets to function. On the other hand, certain types of trading activities by speculators may damage ...
Helfrich, Devin B
Optimal geometries and harmonic vibrational frequencies of the global minima of water clusters (H2O)n, n=2-6, and several hexamer local minima at the CCSD(T) level of theory
We report the first optimum geometries and harmonic vibrational frequencies for the ring pentamer and several water hexamer (prism, cage, cyclic and two book) at the CCSD(T)/aug-cc-pVDZ level of theory. All five hexamer isomer minima previously reported by MP2 are also minima on the CCSD(T) potential energy surface (PES). In addition, all CCSD(T) minimum energy structures for the n=2-6 cluster isomers are quite close to the ones previously obtained by MP2 on the respective PESs, as confirmed by a modified Procrustes analysis that quantifies the difference between any two cluster geometries. The CCSD(T) results confirm the cooperative effect of the homodromic ring networks (systematic contraction of the nearest-neighbor (nn) intermolecular separations with cluster size) previously reported by MP2, albeit with O-O distances shorter by ~0.02 �, indicating that MP2 overcorrects this effect. The harmonic frequencies at the minimum geometries were obtained by the double differentiation of the CCSD(T) energy using an efficient scheme based on internal coordinates that reduces the number of required single point energy evaluations by ~15% when compared to the corresponding double differentiation using Cartesian coordinates. Negligible differences between MP2 and CCSD(T) are found for the librational modes, while uniform increases of ~15 and ~25 cm-1 are observed for the bending and �free� OH harmonic frequencies. The largest differences between MP2 and CCSD(T) are observed for the harmonic hydrogen bonded frequencies. The CCSD(T) red shifts from the monomer frequencies (??) are smaller than the MP2 ones, due to the fact that the former produces shorter elongations (?R) of the respective hydrogen bonded OH lengths from the monomer value with respect to the latter. Both the MP2 and CCSD(T) results for the hydrogen bonded frequencies were found to closely follow the relation - ?? = s ? ?R, with a rate of s = 20.3 cm-1 / 0.001 �. The CCSD(T) harmonic frequencies, when corrected using the MP2 anharmonicities obtained from second order vibrational perturbation theory (VPT2), produce anharmonicCCSD(T) estimates that are within < 60 cm-1 from the measured infrared (IR) active bands of the n=2-6 clusters and furthermore trace the observed red shifts with respect to the monomer (??) quite accurately. The energetic order between the various hexamer isomers on the PES (prism has the lowest energy) previously reported at MP2 was found to be preserved at the CCSD(T) level, whereas the inclusion of anharmonic corrections further stabilizes the cage among the hexamer isomers.
Miliordos, Evangelos; Apra, Edoardo; Xantheas, Sotiris S.
Molecular diagnostics: harmonization through reference ...
... GeT-RM: Genetic Testing Reference Materials Coordination Program; HSS: Department of Health and Human Services; IRMM: Institute for ...
Harmonic engine - Energy Innovation Portal
Solar Photovoltaic; Solar ... invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the ...
6J Harmonic distribution of horizontal COD. A. 1ackson andto closed orbit distortion (COD), and to the effects ofalgorithms to minimize the COD using a combination of the
Jackson, A.
The low-frequency distortion in D-class amplifiers
D-class amplifiers use pulsewidth modulation to transform an input signal u into a rectangular signal p whose duty cycle linearly depends on the input signal u. After low-pass-filtering p to suppress the switching frequency ... Keywords: D-class amplifier, parseval's theorem, pulsewidth modulation (PWM), sampling theorem, switched power converter, uniform sampling
Michael Margaliot; George Weiss
Effects of Mesh Size on Final Residual Stress and Distortion ...
Aerosol Route Synthesis of Copper Oxide Nanoparticles Using Copper Nitrate Solution � AlGaAs-Based Optical ... Defect Energetics and Fission Product Transport in ZrC ... Enhancing Mineral Beneficiation by High Intensity Power Ultrasound.
Will stranded cost recovery distort Pennsylvania`s electricity market?
It is ironic indeed that the forecasting errors of Keystone State utilities that have led to today`s claims of stranded costs are now to be remediated in new legislation which, unaccountably, utterly fails to take account of the same problem: utility forecasting errors. On December 3, 1996, the Governor of Pennsylvania signed into law the Electricity Generation Customer Choice and Competition Act (66 Pa. C.S. 2801 et seq.). The Act set in motion an ambitious timetable for restructuring Pennsylvania`s electric utility industry to substantially deregulate its generation component. Customer choice of electricity supplier is to be phased in over a two year period beginning January 1, 1999. As indicated by the appearance of the word {open_quotes}competition{close_quotes} in the official title of the Act, the resulting institutional transformation is expected to foster free market competition in the generation and retail sale of electricity. However, there is already dispute among the Act`s commentators and critics, who are legion, as to whether its strategy for achieving this commendable objective will produce significant cost savings to consumers any time soon. One need look no further than the Act`s transition cost recovery provisions to find cause for skepticism. Section 2808 of the Act empowers the Pennsylvania Public Utility Commission to impose, for a period of up to nine years from January 1, 1997 (or longer at the Commission`s discretion), a {open_quotes}competitive transition charge{close_quotes} (CTC) upon {open_quotes}every customer accessing the transmission or distribution network.{close_quotes} The CTC is intended to afford Pennsylvania`s regulated electric utilities the opportunity to recover those of their {open_quotes}transition or stranded costs{close_quotes} (collectively {open_quotes}stranded costs{close_quotes}) approved by the Commission.
Caplan, R.L. [Caplan & Luber, Philadelphia, PA (United States)
Financial distortions and the distribution of global volatility.
??In this thesis, I study the interactions between various aspects of the financial system and macroeconomic volatility in a globally integrated environment. In Chapter 1,� (more)
Eden, Maya Rachel
Power-Rate-Distortion Analysis Of Wireless Visual Sensor Network.
??The emergence of low-cost and mature technologies in wireless communication, visual sensor devices, and digtial signal processing, facilitates the potential of wirelss sensor networks (WSN).� (more)
Shaw, William
Atomistic Simulations of Grain Boundary Associated Distortion in ...
... analysis provides a complete three-dimensional reciprocal space map of the grain ... Imaging: Case Studies in Alloys for Aerospace Propulsion Applications.
Photovoltaics in the Czech Republic: example of a distorted market
Analysing the development of "sustainable energy" incentives in the Czech Republic over the last five years and drawing on experience from other countries, the study discovers that the "environmental friendliness" of the so-called "renewable sources", ... Keywords: electricity, energy industry, energy security, environment, investment bubble, photovoltaics, political decisions, renewable sources, wind turbines
Lubo� Smr?ka
Mesocyclone and Microburst Signature Distortion with Dual PRT Radars
A simple model is used to illustrate the limitations of dual pulse repetition time (PRT) radars for measurements of wind fields with strong horizontal wind gradients. In such conditions, errors may occur even if the radial velocity measurements ...
Peter T. May
Credit Market Distortions, Asset Prices and Monetary Policy
decisions. In our framework, ?rms are committed to pay 3the wage bill before production takes place and pro?ts are realized. Although ?rms could alternatively issue new equity, this possibility is a priori excluded. In fact, due to adverse selection... prices is always bene?cial, from a welfare point of view, 4when the central bank considers a term re?ecting stock price volatility in the loss function. Our results point out that responding to asset prices misalignments might be bene?cial when strong...
Pfajfar, D; Santoro, E
Effect of Materials and Quench Process Design on Distortion
Table 5 Suggested carbon content limits for water, brine, and caustic quenching...Table 5 Suggested carbon content limits for water, brine, and caustic quenching Hardening method/shapes Carbon, % max Furnace hardening General usage 0.30 Simple shapes 0.35 Very simple shapes, for example, bars 0.40 Induction hardening Simple shapes 0.50 Complex shapes 0.33...
The Distortion of a Baroclinic Fofonoff Gyre by Wind Forcing
The subtropical recirculation regions are considered as examples of nonlinear free flow��baroclinic Fofonoff gyres.� In the interior, where relative vorticity may be neglected, the quad-geostrophic assumption may be relaxed, and the layered ...
A. J. George Nurser
Distortion management in slow-light pulse delay
measurements of the time of flight of photons in a three-dimensional photonic crystal," Phys. Rev. E 60, 1030 Ed. (Prentice Hall, Upper Saddle River, 1997). 15. Y. Chen, G. Pasrija, B. Farhang-Boroujeny, and S
Gauthier, Daniel
Financial distortions and the distribution of global volatility
In this thesis, I study the interactions between various aspects of the financial system and macroeconomic volatility in a globally integrated environment. In Chapter 1, I illustrate that an efficient allocation of liquidity ...
Measurement of neutrino oscillation with Kamland: Evidence of spectral distortion
Duke University, North Carolina State University, and the University of North Carolina at Chapel Hill Institute of High Energy
Correction of Motional Electric Field Measurements for Galvanic Distortion
Interactions between motional electric fields and lateral gradients in electrical conductivity (e.g., seafloor topography) produce boundary electric charges and galvanic (i.e., noninductive) secondary electric fields that result in frequency-...
Alan D. Chave; Douglas S. Luther; Christopher S. Meinen
Harmonization of CIM with IEC Standards
EPRI has sponsored development of a number of international standards that provide the basis for information exchange to support power system management. One of the most important is the Common Information Model (CIM), which is rapidly gaining acceptance throughout the world as a common semantic model to unify and integrate data from a myriad of systems involved in support of real-time electric utility operations. As its acceptance as the basis for information integration grows and areas of application e...
Example A: Data center with electric and natural gas (Co-generation) purchase o Cogeneration Input Fuel Assumption This taskforce has adopted the assumption that 67% of a...
Harmonic Air Motor - Lawrence Livermore National Laboratory
Current Weather. Protocol Office. Where to stay. Tri-Valley Visitors Bureau. City of Livermore. Community. Our Community. Discovery Center. ... such ...
能效标准、标识和认证 能效标准、标识和认证 区域协调与互认 李铁男, 研究员 国宏美亚(北京)工业节能减排技术促进中心 主任 ISO/TC 257 节能量 主席 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE) 能效标准、标识和认证的作用 能效标准、标识和认证区域合作关注点与障碍 最佳实践:亚洲能效标准和标识/认证有效建立和实 施障碍消除项目(BRESL ) 建议 主要内容 国宏美亚(北京)工业节能减排技术促进中心 Center for Industrial Energy Efficiency (CIEE) 识别节能产品
T. tengcongensis (Tt H-NOX), the reduction potential wasdesign of Tt H-NOX to broaden the reduction potential rangewith Tt H-NOX show that the reduction potential is
Multilevel Cascade H-bridge Inverter DC Voltage Estimation Through Output Voltage Sensing
- level inverters with symmetric supply," in Proc. 35th IEEE Power Electronics Specialists Conference, vol Knoxville,USA email@example.com, firstname.lastname@example.com Burak Ozpineci Energy & Transportation Science Division Oak total harmonic distortion), and have less switching losses. However, they need more components, driver
Power quality assessment of specially connected transformers
This paper examines and compares the voltage deviation, voltage unbalance, and harmonic distortion of V-V, Scott, and Le Blanc connected transformers by a novel approach. The power quality factors are needed to truly reflect the loading characteristics ... Keywords: Le Blanc connection, V-V connection, power quality, scott connection
Yao-Hung Chan; Chi-Jui Wu; Shu-Chen Wang
Stabilizing technique for AC-DC boost PFC converter based on time delay feedback
It is well known that the ac-dc power factor correction (PFC) boost preregulator can present instability at the line frequency. This nonlinear phenomenon can jeopardize the system performances by increasing the total harmonic distortion and decreasing ... Keywords: ac-dc converters, line frequency instability, power factor correction (PFC), time delay feedback (TDF)
Abdelali El Aroudi; Mohamed Orabi
Digital protection systems response to sequence and phase components in non sinusoidal operation conditions
Traditional open literature about protection systems documents the use of residual currents or voltages (zero sequence components) and negative sequence components of currents or voltages to detect and protect the different power system elements against ... Keywords: digital protection systems, harmonic distortion, negative sequence, non sinusoidal operation, phase components, zero sequence
F. Mart�nez-C�rdenas; A. Medina
Energy Performance and Emissions of Electronic Ballasts Powering 4-Foot Fluorescent Lamps
This power quality (PQ) case study presents tests performed at the Worcester Polytechnic Institute, in contract with the EPRI Power Electronics Applications Center (PEAC) to determine the average efficacy (lumens per watt), displacement power factor, total power factor, and current harmonic distortion of modern electronic ballasts powering fluorescent lamps.
Optimization of wind turbine energy and power factor with an evolutionary computation algorithm
Optimization of wind turbine energy and power factor with an evolutionary computation algorithm the energy capture from the wind and enhance the quality of the power produced by the wind turbine, and harmonic distortion. As the generation of wind energy on an industrial scale is relatively new, the area
Kusiak, Andrew
NREL: Energy Analysis - Life Cycle Assessment Harmonization Methodolog...
factors qualitatively evaluated for nuclear, including uranium ore grade, primary source energy mix and LCA method. 3 The specific system boundary varied by study. By reducing the...
expanded to provide measurement guidelines and next steps for three additional metrics; Green Energy Coefficient (GEC), Energy Reuse Factor (ERF), and Carbon Usage Effectiveness...
GyroSole Harmonic Engine and Power System
This differs from the typical solar power photovoltaic-conversion of heat energy into electrical energy, ... (Residential Solar Thermal Power Plant), ...
Beam Conditioning and Harmonic Generation in Free Electron Lasers
Meth. A 429, 243 (1999). LCLS Design Study Group, ReportFELs) such as Euro- XFEL and LCLS are to be devices whichproposed at Euro-XFEL or the LCLS, are designed to generate
Charman, A.E.; Penn, G.; Wolski, A.; Wurtele, J.S.
D4, Second Harmonic Generation in a Metamaterial Resonating at ...
A pair of ultra wide band dipole antennas was used as a transmitter and a receiver. ... C2, Measurement of Nanoscale External Quantum Efficiency of Plastic Solar ... D1, Tuning of Plasmonic Cavity Resonances Using Atomic Layer Deposition.
Campbell Soup Company: Harmonizing Processes and Empowering Workers
In 2007 Campbell Soup Company was implementing Project Harmony: a multi-year effort to implement SAP and create more standardized and integrated business processes across
Ross, Jeanne W.
Best Approximation in the Mean by Analytic and Harmonic Functions
* *ng the annihilator Ann (Hp) in Lq(T, d`)as Hq0= {f 2 Hq : f(0) = 0}, q = __p__pt-u1rns* * out is organized as follows. In Section 2we prove the exi* *stence of best approximations and characterize them
McCarthy, John E.
Harmonic approaches to non-intrusive load diagnostics
The Non-Intrusive Load Monitor (NILM) is a system that monitors, records and processes voltage and current measurements to establish the operating characteristics of individual loads on a load center from a single aggregate ...
Fuller, Ashley E. (Ashley Eliot)
Premixed flame kinematics in a harmonically oscillating velocity field .
??Air pollution regulations have driven modern power generation systems to move from diffusion to premixed combustion. However, these premixed combustion systems are prone to combustion� (more)
Shin, Dong-hyuk
Effect of harmonic forcing on turbulent flame properties .
??Lean premixed combustors are highly susceptible to combustion instabilities, caused by the coupling between heat release fluctuations and combustor acoustics. In order to predict the� (more)
Thumuluru, Sai Kumar
Novel Control and Harmonics Impact of PV Solar Farms.
??This thesis presents a novel application of Photovoltaic (PV) solar system inverter, both during night and day, as a dynamic reactive power compensator STATCOM. This� (more)
Das, Byomakesh
Harmonic launching of ion Bernstein waves via mode transformation
Ion Bernstein wave excitation and propagation via finite ion-Larmor-radium mode-transformation are investigated theoretically and experimentally. It is shown that in the ion cyclotron range of frequencies omega less than or equal to 4..cap omega../sub i/, with modest ion temperatures (T/sub i/ less than or equal to 10 eV), the finite-Larmor-radius effect removes the wave singularity at lower-hybrid resonance layer, enabling an externally initiated electron plasma wave to transform continuously into an ion Bernstein wave. In an ACT-1 hydrogen plasma (T/sub e/ approx. = 2.5 eV, T/sub i/ less than or equal to 2.0 eV), externally excited ion Bernstein waves have been observed for omega less than or equal to 2..cap omega../sub i/ as well as for omega less than or equal to 3..cap omega../sub i/. The finite ion-Larmor-radius mode transformation process resulting in strong ion Bernstein wave excitation has been experimentally verified. Detailed measurements of the wave dispersion relation and of the wave-packet trajectory show excellent agreement with theory. The dependence of the excited ion Bernstein wave on the antenna phasing, the plasma density, and on the neutral pressure (T/sub i/) is also investigated.
Ono, M.; Wong, K.L.; Wurden, G.A.
Tidal flow over threedimensional topography generates outofforcingplane harmonics
energy conversion from the barotropic to the baroclinic tide. The generation of internal waves by tidal, a significant amount of the energy converted from barotropic to baroclinic tides can be generated perpendicular of a sphere, J. Fluid Mech., 183, 439450. Baines, P. G. (2007), Internal tide generation by seamounts, Deep
Texas at Austin. University of
NREL: Energy Analysis - Life Cycle Assessment Harmonization Results...
image Published Results The published life cycle greenhouse gas (GHG) estimates for hydropower, ocean, geothermal, biopower, solar (crystalline silicon photovoltaic, thin...
Harmonization of Energy Generation Life Cycle Assessments (LCA...
6 kgmmBTU to 33 kgmmBTU and 45 gmmBTU to 65 gmmBTU for soybean biodiesel and corn grain ethanol, respectively. There is also no consistency between the magnitude of...
Flows and Decompositions of Games: Harmonic and Potential Games
142�154, Washington, DC, USA, 2005. IEEE Computer Society. [15] G.H. Golub and C.F. Van Loan. Matrix computations. Johns Hopkins University Press, 1996.
Wind LCA Harmonization (Fact Sheet), NREL (National Renewable...
(30% for land-based and 40% for offshore systems). 2. Operating lifetime of the wind turbine and its components (20 years). 3. System boundary. 4. Global warming potentials...
Regulatory Harmonization and the Development of Private Equity Markets
ensure that the financial statements of all listed companiestheir consolidated financial statements. The Dutch went one
Cumming, Douglas; Johan, Sofia
Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas
Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.
Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL
Spherical harmonic analysis and synthesis for global multiresolution ...
noble identities which are illustrated using the Z transform as follows: ??? ! .... search Grant to the first author on Multiresolution Analysis of. Inverse Problems in
Temperature-insensitive phase-matched optical harmonic conversion crystal
Temperature-insensitive, phase-matched harmomic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions.
Barker, Charles E. (Sunnyvale, CA); Eimerl, David (Livermore, CA); Velsko, Stephan P. (Livermore, CA); Roberts, David (Sagamore Hills, OH)
GyroSol� Harmonic Engine - Home - Energy Innovation Portal
existing HVAC system � Fuel efficiency ~ 90% � Payback < 1 year . 19 GyroSol� engine can save lives�.
Spherical Harmonic Analysis of a Model-Generated Climatology
Monthly mean fields of 850 mb temperature (T850), 500 mb geopetential height (G500) and sea level pressure (SLP) were generated in the course of a 5-year climate simulation run with a global general circulation model. Both the model-generated ...
Zaphiris D. Christidis; Jerome Spar
Current Weather. Protocol Office. Where to stay. Tri-Valley Visitors ... This differs from the typical solar power photovoltaic-conversion of heat ...
LIGHTS: Laboratory for Information Globalization and Harmonization Technologies and Studies
Three important trends - unrelenting globalization, growing worldwide electronic connectivity, and increasing knowledge intensity of economic activity - are creating new opportunities for global politics, with challenging ...
Choucri, Nazli
Harmon County, Oklahoma: Energy Resources | Open Energy Information
5114°, -99.8124935° 5114°, -99.8124935° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":34.7305114,"lon":-99.8124935,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Time-Mode Analog Circuit Design for Nanometric Technologies
Rapid scaling in technology has introduced new challenges in the realm of traditional analog design. Scaling of supply voltage directly impacts the available voltage-dynamic-range. On the other hand, nanometric technologies with fT in the hundreds of GHz range open opportunities for time-resolution-based signal processing. With reduced available voltage-dynamic-range and improved timing resolution, it is more convenient to devise analog circuits whose performance depends on edge-timing precision rather than voltage levels. Thus, instead of representing the data/information in the voltage-mode, as a difference between two node voltages, it should be represented in time-mode as a time-difference between two rising and/or falling edges. This dissertation addresses the feasibility of employing time-mode analog circuit design in different applications. Specifically: 1) Time-mode-based quanitzer and feedback DAC of SigmaDelta ADC. 2) Time-mode-based low-THD 10MHz oscillator, 3) A Spur-Frequency Boosting PLL with -74dBc Reference-Spur Rejection in 90nm Digital CMOS. In the first project, a new architectural solution is proposed to replace the DAC and the quantizer by a Time-to-Digital converter. The architecture has been fabricated in 65nm and shows that this technology node is capable of achieving a time-matching of 800fs which has never been reported. In addition, a competitive figure-of-merit is achieved. In the low-THD oscillator, I proposed a new architectural solution for synthesizing a highly-linear sinusoidal signal using a novel harmonic rejection approach. The chip is fabricated in 130nm technology and shows an outstanding performance compared to the state of the art. The designed consumes 80% less power; consumes less area; provides much higher amplitude while being composed of purely digital circuits and passive elements. Last but not least, the spur-frequency boosting PLL employs a novel technique that eliminates the reference spurs. Instead of adding additional filtering at the reference frequency, the spur frequency is boosted to higher frequency which is, naturally, has higher filtering effects. The prototype is fabricated in 90nm digital CMOS and proved to provide the lowest normalized reference spurs ever reported.
Elsayed, Mohamed
Quantitative susceptibility mapping and susceptibility-based distortion correction of echo planar images
The field of medical image analysis continues to expand as magnetic resonance imaging (MRI) technology advances through increases in field strength and the development of new image acquisition and reconstruction methods. ...
Poynton, Clare (Clare Brenna)
Distortion of low-frequency acoustic signals by interaction with the moving ocean surface
A moving upper boundary in ocean acoustics . . . . . . 1.21.3 Foundations for studying ocean surface wave in?uence onmodels . . . . . . . . . . . 1.3.2 Ocean surface wave
Lynch, Stephen Dennis
Gravitational lens magnification by Abell 1689: Distortion of the background galaxy luminosity function
Gravitational lensing magnifies the luminosity of galaxies behind the lens. We use this effect to constrain the total mass in the cluster Abell 1689 by comparing the lensed luminosities of background galaxies with the luminosity function of an undistorted field. Since galaxies are assumed to be a random sampling of luminosity space, this method is not limited by clustering noise. We use photometric redshift information to estimate galaxy distance and intrinsic luminosity. Knowing the redshift distribution of the background population allows us to lift the mass/background degeneracy common to lensing analysis. In this paper we use 9 filters observed over 12 hours with the Calar Alto 3.5m telescope to determine the redshifts of 1000 galaxies in the field of Abell 1689. Using a complete sample of 151 background galaxies we measure the cluster mass profile. We find that the total projected mass interior to 0.25h^(-1)Mpc is (0.48 +/- 0.16) * 10^(15)h^(-1) solar masses, where our error budget includes uncertainties from the photometric redshift determination, the uncertainty in the off-set calibration and finite sampling. This result is in good agreement with that found by number count and shear-based methods and provides a new and independent method to determine cluster masses.
S. Dye; A. N. Taylor; E. M. Thommes; K. Meisenheimer; C. Wolf; J. A. Peacock
Evaluation and Correction of the Non-linear Distortion of CEBAF Beam Position Monitors
The beam position monitors at CEBAF have four antenna style pickups that are used to measure the location of the beam. There is a strong nonlinear response when the beam is far from the electrical center of the device. In order to conduct beam experiments at large orbit excitation we need to correct for this nonlinearity. The correction algorithm is presented and compared to measurements from our stretched wire BPM test stand.
M. Spata, T.L. Allison, K.E. Cole, J. Musson, J. Yan
Ch. 27 Solidification Macroprocesses (Thermal-mechanical Modeling of Stress, Distortion and Hot Tearing)
-Champaign in Materials Processing Handbook, J.R. Groza, J.F. Shackelford, E.J. Lavernia & M.T. Powers (eds.), Chapter 27 in "Materials Processing Handbook, Joanna R. Groza, James F. Shackelford, Editors (Ed.) (2007) Chapter 27 - ISBN
Paris-Sud XI, Université de
Objective video quality assessment method for video streams spatially distorted by coding and packet loss
In recent years, video-streaming services and videoconferencing services have become among the most promising of multimedia communications applications. To make high-quality video-streaming services that are comfortable to view, we need to design appropriate ... Keywords: image quality, objective quality assessment, quality of experience, video streaming
Jun Okamoto; Keishiro Watanabe; Takaaki Kurita
Fast correction of bleed-through distortion in grayscale documents by a blind source separation technique
Ancient documents are usually degraded by the presence of strong background artifacts. These are often caused by the so-called bleed-through effect, a pattern that interferes with the main text due to seeping of ink from the reverse side. A similar effect, ... Keywords: Bleed-through cancellation, Blind source separation, Grayscale document restoration, Independent component analysis
Anna Tonazzini; Emanuele Salerno; Luigi Bedini
PHYSICAL REVIEW C 80, 025807 (2009) Effects of distortion of the intercluster motion in 2
. F. P., Pakistan (Received 19 March 2009; published 31 August 2009) Deuteron induced quasifree He, and 9 Be induced reactions. This was done not only for the investigation of nuclear structure for nuclear astrophysics. DOI: 10.1103/PhysRevC.80.025807 PACS number(s): 25.60.Gc, 26.20.-f, 21.10.Pc, 24
Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University
Laboratory Measurements of Small Raindrop Distortion. Part 2: Oscillation Frequencies and Modes
The oscillation frequencies and modes of small raindrops (1.04�1.54-mm diameter) were determined from laboratory experiments using water drops generated at terminal velocity at a fall distance sufficient for initial oscillations to damp out. ...
Kenneth V. Beard; Rodney J. Kubesh
Laboratory Measurements of Small Raindrop Distortion. Part I: Axis Ratios and Fall Behavior
The resonant interactions between eddy shedding and drop oscillations postulated by Gunn for millimeter diameter raindrops were investigated in a series of laboratory measurements of axis ratio and fall behavior for water drops of d = 0.70�1.54 ...
Kenneth V. Beard; Rodney J. Kubesh; Harry T. Ochs III
Advection, Phase Distortion, and the Frequency Spectrum of Finescale Fields in the Sea
Continuous depth�time measurements of upper-ocean velocity are used to estimate the wavenumber�frequency spectrum of shear. A fundamental characteristic of these spectra is that the frequency bandwidth increases linearly with increasing ...
Robert Pinkel
Inlet swirl distortion effects on the generation and propagation of fan rotor shock noise
A body-force-based fan model for the prediction of multiple-pure-tone noise generation is developed in this thesis. The model eliminates the need for a full-wheel, three-dimensional unsteady RANS simulation of the fan blade ...
Defoe, Jeff (Jeffrey James)
Burning desires An obsession with oil distorts an account of the
Energy Systems Figure 3 100 mb/d Crude oil: currently producing fields Unconventional oil Natural gasAvailable online at www.sciencedirect.com Future world oil production: growth, plateau, or peak? Larry Hughes and Jacinda Rudolph With the exception of two oil shocks in the 1970s, world oil production
Smil, Vaclav
Allocation, incentives and distortions: the impact of EU ETS emissions allowance allocations to the electricity sector
NE allocation is used. The allocation results in accelerated construction and operation of combined cycle gas turbines and thus lower CO2 emissions. For our given set of input parameters, the results for uniform-benchmark or fuel-specific benchmark... allocation on activities in Phase I is explicitly prohibited by the EU Directive, some MSs update allocations using fuel-specific benchmarks (FSB) where the benchmark is set higher for coal-fired plants than for gas-fired plants. Here, we assess the impact...
Neuhoff, Karsten; Keats, Kim; Sato, Misato
Welfare effects of biofuel policies in the presence of environmental externalities and pre-existing distortions.
??Policy intervention in the biofuel market has led to a significant increase in biofuel production and use in the past several years. However, the welfare� (more)
Lasco, Marie Christine D.
Custom Power Primer Version 1.0
Voltage sags, momentary interruptions, harmonic distortion, and voltage flicker are among the most common power quality variations affecting industrial and commercial end-users. Solving these problems will require a great deal of cooperation. This report focuses on devices that are classified as custom power solutions. For voltage sag, swell, and interruption mitigation, the following custom power controllers are examined: static series compensator (SSC) devices, static voltage regulator (SVR) devices, b...
Modification of electrical conductivity in T-10 by electron cyclotron heating
The CQL3D Fokker-Planck code is used to investigate effects of quasilinear distortion of the electron tail in the T-10 second harmonic electron cyclotron current (ECCD) drive experiment. The experiment operates in a regime of substantial tail formation. Current drive efficiency may be doubled relative to low power cases, That portion of electric field-driven current which is synergetic with the rf-induced nonthermal tail may tend to cancel the ECCD current in relevant cases.
Harvey, R.W.; Forest, C.B.; Sauter, O.; Lohr, J.; Lin-Liu, Y.R.
Accounting for Surface Wave Distortion of the Marine Wind Profile in Low-Level Ocean Storms Wind Measurements
Marine wind measurements at three heights (3.0,4.5, and 5.0 m) from both moored and drifting buoys during the Ocean Storms Experiment are described. These winds are compared with each other, with winds from ships, from subsurface ambient acoustic ...
W. G. Large; J. Morzel; G. B. Crawford
Does the Influence of Oblate-Like Distortions in Larger Raindrops Make a Difference in Collection and Evaporation Parameterizations?
This note documents the results of more exact parameterizations for continuous-collection growth and evaporation against simpler traditional ones. Although the main focus is on improving research models, the research results also apply to high-...
Jerry M. Straka; Matthew S. Gilmore
Evaluation of the Flow Distortion around the Campbell Scientific CSAT3 Sonic Anemometer Relative to Incident Wind Direction
In June 2002, a high-frequency air�sea momentum system was deployed in the surf zone for 3 days as part of an experiment to quantify air�sea momentum transfer when the wind and wave direction were at angles. The system obtained measurements in ...
Harry C. Friebel; Thomas O. Herrington; Alexander Y. Benilov
Polar distortion in ultra-thin BaTiO3 films by in situ LEED-IV
Phase stability in nanoscale ferroelectrics is governed by the interplay of electrostatic depolarization energy, domain formation, adsorption, and surface band bending. Using in situ low-energy electron-diffraction intensity versus voltage (LEED I-V), we have characterized 4 and 10 ML BaTiO{sub 3} films, grown using pulsed laser deposition with fully compressive strain on a SrRuO{sub 3}/SrTiO{sub 3} substrate. LEED I-V reveals a single surface dead layer and a monodomain vertically polarized state below. The single orientation is attributed to the intrinsic imprint asymmetry and the stability of a polarized phase to compensation of depolarizing charges by dipoles induced by surface stress.
Shin, Junsoo [ORNL; Nascimento, Von B [ORNL; Borisevich, Albina Y [ORNL; Plummer, E Ward [ORNL; Kalinin, Sergei V [ORNL; Baddorf, Arthur P [ORNL
CFD Model Estimates of the Airflow Distortion over Research Ships and the Impact on Momentum Flux Measurements
Wind velocity and air�sea turbulent flux measurements made from shipborne instruments are biased due to the effect of the ship on the flow of air to the instruments. The presence of the ship causes the airflow to a particular instrument site to ...
M. J. Yelland; B. I. Moat; R. W. Pascal; D. I. Berry
Modeling of complex oxide materials from the first principles: systematic applications to vanadates RVO3 with distorted perovskite structure
"Realistic modeling" is a new direction of electronic structure calculations, where the main emphasis is made on the construction of some effective low-energy model entirely within a first-principle framework. Ideally, it is a model in form, but with ... Keywords: Effective models, First-principle calculations, Perovskite vanadates, Spin-orbital order
Igor Solovyev
Distortion and Noise Performance of BottomPlate Sampling Mixers Wei Yu, Bosco Leung, Senior Member, IEEE
of a MOS tran sistor followed by a sampling capacitor (Fig. 1). The in put VRF is at RF or IF frequency
Yu, Wei
Waveform Distortion on a 7-Channel Heart Monitor Produced by a Worn Cable Connector & 60-Hertz Electromagnetic Fields
This case study describes an equipment-to-electromagnetic environment incompatibility that occurred in a training laboratory that is part of a large teaching hospital. Specifically, it discusses the causes of low-frequency electromagnetic fields that led to the malfunction of a 7-channel heart monitor used in cardiovascular surgical training to monitor, record, and display small electrical impulses associated with the heart.
Photovoltaic power conditioning subsystem: state of the art and development opportunities
Photovoltaic sytems, the state of the art of power conditioning subsystem components, and the design and operational interaction between photovoltaic systems and hot utilities are detailed in this document. Major technical issues relating to the design and development of power conditioning systems for photovoltaic application are also considered, including: (1) standards, guidelines, and specifications; (2) cost-effective hardware design; (3) impact of advanced components on power conditioning development; (4) protection and safety; (5) quality of power; (6) system efficiency; and (7) system integration with the host utility. In addition, theories of harmonic distortion and reactive power flow are discussed, and information about power conditioner hardware and manufacturers is provided.
Krauthamer, S.; Bahrami, K.; Das, R.; Macie, T.; Rippel, W.
M �xico Sello FIDE USA Energy Star & Green Seal Comparativelabel. Sello FIDE Energy Star Green Seal Manufacturersand applying the Energy Star logos. Green Seal Voluntary.
A fast spherical harmonics transform for global NWP and climate models
Very high resolution spectral transform models are believed to become prohibitively expensive, due to the relative increase in computational cost of the Legendre transforms compared to the gridpoint computations. This article describes the ...
Nils P. Wedi; Mats Hamrud; George Mozdzynski
Reduced-Reference Video Quality Assessment using Discriminative Local Harmonic Strength with Motion Consideration
Gunawan,I.P. Ghanbari,M. Accepted for publication in the IEEE Trans. on Circuits and Systems for Video Technology IEEE
Gunawan, I.P.
FERMI @ Elettra -- A Seeded Harmonic Cascade FEL for EUV and Soft X-rays
laser systems for a FEL user facility�, M.B Danailov, F. �.will be the first user facility based on seeded harmonicsystem intended for a user facility that is operated on a
An Enhanced GINGER Simulation Code with Harmonic Emission and HDF5 IO Capabilities
S. Reiche. I also thank the LCLS project of?ce at SLAC for ?1 (2004); see also http://www- ssrl.slac.stanford.edu/lcls/lcls tech notes.html/LCLS-TN- 04-3.pdf . [2] National Center
Fawley, William M.
Higher Fourier Harmonics of the Directional Distribution of an Equilibrium Wave Field under Steady Wind Forcing
Recently, directional wave spectra have been obtained by applying the two-dimensional fast Fourier transform (2D FFT) to the three-dimensional spatial topography of ocean surface waves collected by an airborne scanning laser ranging system during ...
David W. Wang; Paul A. Hwang
A Dynamical Core with Double Fourier Series: Comparison with the Spherical Harmonics Method
A dynamical core of a general circulation model with the spectral method using double Fourier series (DFS) as basis functions is presented. The model uses the hydrostatic balance approximation and sigma coordinate system in the vertical direction ...
Hyeong-Bin Cheong
Harmonization and Sharing of Data from International Fuel Cell Bus Demonstrations (Presentation)
This presentation, which was given by NREL's Leslie Eudy at the 2006 Fuel Cell Seminar, provides information on international fuel cell bus demonstrations.
Eudy, L.
Harmonic control of multiple-stator induction machines for voltage regulation
Small, one to a few horsepower, three-phase induction machines with three sets of electrically-isolated, magnetically-coupled stator winding circuits are described. A voltage inverter is developed and used to drive one set ...
Holloway, Jack Wade, 1980-
Efficiency Labels and Standards: A Guidebook for Appliances,Labeling and Appliance Standards Program (CLASP). Availableof energy efficiency test standards and regulations in APEC
BFlavor: A harmonized approach to media resource adaptation, inspired by MPEG-21 BSDL and XFlavor
During recent years, several tools have been developed that allow the automatic generation of XML descriptions containing information about the syntax of binary media resources. Such a bitstream syntax description (BSD) can then be transformed to reflect ... Keywords: BFlavor, Content adaptation, H.264/AVC, MPEG-21 BSDL, Multimedia, SEI messages, Sub-sequences, Temporal scalability, XFlavor
Wesley De Neve; Davy Van Deursen; Davy De Schrijver; Sam Lerouge; Koen De Wolf; Rik Van de Walle
L mc ,S m L ve ** ,S m Dishwashers L mc ,L ve ,S m L mc ,LClothes washers Clothes washers and dryers DishwashersDishwashers Fluorescent lamp ballasts Fluorescent lamp
The Vector Harmonic Transform Method for Solving Partial Differential Equations in Spherical Geometry
The development of computational methods for solving partial differential equations in spherical geometry is complicated by problems induced by the spherical coordinate system itself. Even though the solution is smooth in Cartesian coordinates, ...
Paul N. Swarztrauber
Quantum dephasing of a two-state system by a nonequilibrium harmonic oscillator
In this paper, we investigate coherent quantum dynamics in a nonequilibrium environment. We focus on a two-state quantum system strongly coupled to a single classical environmental oscillator, and explore the effect of nonstationary statistical properties of the oscillator on the quantum evolution. A simple nonequilibrium model, consisting of an oscillator with a well-defined initial phase which undergoes subsequent diffusion, is introduced and studied. Approximate but accurate analytic expressions for the evolution of the off-diagonal density matrix element of the quantum system are derived in the second-order cumulant approximation. The effect of the initial phase choice on the subsequent quantum evolution is quantified. It is observed that the initial phase can have a significant effect on the preservation of coherence on short time scales, suggesting this variable as a control parameter for optimizing coherence in many-body quantum systems.
Martens, Craig C. [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States)
Two-Dimensional Radiative Transfer in Cloudy Atmospheres: The Spherical Harmonic Spatial Grid Method
A new two-dimensional monochromatic method that computes the transfer of solar or thermal radiation through atmospheres with arbitrary optical properties is described. The model discretizes the radiative transfer equation by expanding the angular ...
Harmonizing the International Electrotechnical Commission Common Information Model (CIM) and 61850
The Electric Power Research Institute (EPRI) has sponsored the development of a number of international standards that provide the basis for information exchange to support power system management. One of the most important standards is the International Electrotechnical Commission (IEC) Common Information Model (CIM), which is rapidly gaining acceptance throughout the world as a common semantic model to unify and integrate the data from numerous systems involved in the support of real-time electric util...
Adaptation of Classical Tidal Harmonic Analysis to Nonstationary Tides, with Application to River Tides
One of the most challenging areas in tidal analysis is the study of nonstationary signals with a tidal component, as they confront both current analysis methods and dynamical understanding. A new analysis tool has been developed, NS_TIDE, adapted ...
Pascal Matte; David A. Jay; Edward D. Zaron
Estimating the Integrated Likelihood via Posterior Simulation Using the Harmonic Mean Identity
the situation where, roughly speaking, the level-w contour of the likelihood function has the form ^ +anwr S
Washington at Seattle, University of
of the likelihood function has the form ^ + anwr S, where ^ is the maximum likelihood estimator, r > 0 is a constant
Second Harmonic Generation and Confined Acoustic Phonons in Highly Excited Semiconductor Nanocrystals
spherical and the rod-shape CdSe nanocrystals. Figure 6. (dependence of the oscillation in CdSe nanocrystals. (B) Pumpamplitude in spherical CdSe nanocrystals. F.1 F.2 F.3 F.4
Son, Dong Hee; Wittenberg, Joshua S.; Banin, Uri; Alivisatos, A. Paul
Achromatic phase-matching second harmonic generation for a tunable laser
An optical system uses a nonlinear optical medium to alter the frequency of a relatively narrow band light source tunable over a plurality of different frequencies using an optical system for passively directing light to the nonlinear medium at a correct phase matching angle. In this manner, the light from the tunable light source can be efficiently frequency-doubled or frequency-tripled without the need of moving parts. An all prism design provides a system of optimal efficiency. 6 figs.
Jacobson, A.G.; Bisson, S.; Trebino, R.
An optical system uses a nonlinear optical medium to alter the frequency of a relatively narrow band light source tunable over a plurality of different frequencies using an optical system for passively directing light to the nonlinear medium at a correct phase matching angle. In this manner, the light from the tunable light source can be efficiently frequency-doubled or frequency-tripled without the need of moving parts. An all prism design provides a system of optimal efficiency.
Jacobson, Alexander Gerson (Danville, CA); Bisson, Scott (Livermore, CA); Trebino, Rick (Livermore, CA)
Harmonization of Utility Common Information Model (CIM) with other IEC Power System Management Standards
EPRI has sponsored the development of a number of international standards which provide the basis for information exchange to support power system management. One of the most important is the Common Information Model (CIM), which is rapidly gaining acceptance throughout the world as a common semantic model to unify and integrate the data from a myriad of systems involved in support of real-time electric utility operations. As its acceptance as the basis for information integration grows and areas of appl...
Does India need to harmonize the law of patent exhaustion and parallel imports?
The amendment of patent law of India in 2005 to fulfill her international obligation under the TRIPS Agreement (World Trade Organization Agreement on Trade Related Intellectual Property Rights) was an outcome of an attempt to balance the competing interests ... Keywords: TRIPS Agreement, exclusive rights exhaustion, national, parallel imports, regional and international exhaustion
Rajnish Kumar Rai