text:
Office of Scientific and Technical Information
Ventyx, an ABB Company
Gasoline and Diesel Fuel Update (EIA)
Ventyx, an ABB Company Ventyx, an ABB Company 1495 Canyon Blvd Suite 100 Boulder, CO 80302 (t) 720.240.5500 www.ventyx.com April 30, 2013 Ms. Rebecca Peterson U.S Department of Energy, U.S. Energy Information Administration, Mail Stop EI-23, Forrestal Building, 1000 Independence Avenue SW., Washington, DC 20585 Re: Proposed changes to Energy Information Administration Forms EIA-63B, EIA-411, EIA-826, EIA-860, EIA-860M, EIA-861, EIA-861S, and EIA-923. Federal Register Vol. 78 No. 44, Wednesday March 6, 2013. Dear Ms. Peterson: We appreciate the time and effort the Energy Information Administration spends collecting, maintaining and distributing industry wide data. The data found in EIA forms 923, 860, 860M, 861 and 826 is the industry standard and used by market analysts and
NREL/Ventyx Utility Rates: What is included? | OpenEI Community
Open Energy Info (EERE)
NREL/Ventyx Utility Rates: What is included? NREL/Ventyx Utility Rates: What is included? Home > Groups > Utility Rate Does anyone know what pieces of electric rates are included in the NREL/Ventyx database of rates by utility, i.e. is it supply only or does the file include supply, transmission & distribution costs? Thanks! Submitted by Vbugnion on 27 February, 2013 - 16:25 1 answer Points: 1 Hi Vbugnion, Just to clarify, you're not asking about the OpenEI utility rates, but rather the Ventyx rates found here: http://developer.nrel.gov/doc/api/georeserv/service/utility_rates If so, then the Ventyx rates do include all bundled rates (which includes supply, trans, and distr costs). However, there's a small but non-zero possibility that a few energy-only or delivery-only rates may not have been cleaned
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
worldPower 2010 worldPower 2010 1 T he utility world has changed drastically in the last 10 years. New technologies like Smart Meters and fully functional Smart Grid concepts have made large inroads into the utility space and no one should want to be left behind. Utilities also face additional pressures from regulatory bodies who are continuing to encourage carbon reduction and greater customer flexibility. Utilities need to balance these new requirements with the financial obligations of providing reliable power (at a reasonable price) while attempting to meet shareholder expectations. Each of these goals are not necessarily complimentary, thus utilities need to determine how to address each one. Some of the ways utilities are addressing these concepts is through the rollout of dynamic pricing for reducing peak-load,
Science Conference Proceedings (OSTI)
... Delta t ffl \\Delta t = 1ns. Pulse-Dri ven Wall Motion ( ff = ... varies, can increase (!), eventually decays tozero. Pulse-Dri ven Domain Wall Velocity ( ff = ...
LANL Go Suite
NLE Websites -- All DOE Office Websites (Extended Search)
LANL Go Suite LANL Go Suite LANL Go Suite The LANL Go Suite is a collection of packages, libraries, utilities, and software patches related to Google's Go programming language (http://www.golang.org/). September 24, 2013 software Available for thumbnail of Feynman Center (505) 665-9090 Email LANL Go Suite The LANL Go Suite is a collection of packages, libraries, utilities, and software patches related to Google's Go programming language (http://www.golang.org/). The LANL Go Suite largely takes a high-performance computing angle to Go by providing some of the mechanisms needed to use Go in a supercomputing environment. For instance, the LANL Go Suite provides a Go interface to PAPI, the University of Tennessee at Knoxville's Performance Application Programming Interface (http://icl.cs.utk.edu/papi/), which helps software developers identify
Energy Science and Technology Software Center (OSTI)
002851IBMPC00 STAYSL PNNL SuiteÝ http://radiochemscieng.pnnl.gov/research_areas/research_area_description.asp?id=283Ý
BESTEST Test Suites
BESTEST Test Suites BESTEST (Building Energy Simulation TEST) is a method for testing, diagnosing, and validating the capabilities of building energy simulation programs. The...
Directed Test Suite Augmentation.
E-Print Network (OSTI)
??Test suite augmentation techniques are used in regression testing to identify code elements affected by changes and to generate test cases to cover those elements.Ö (more)
Xu, Zhihong
Security Suites | ornl.gov
Security Suites Available by Internet Service Providers Comcast Comcast offers the Norton Security Suite with antivirus and firewall software for your protection, for no additional...
Velocity pump reaction turbine
DOE Patents (OSTI)
An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.
House, Palmer A. (Walnut Creek, CA)
BRC-CBEFF Conformance Test Suite
... technical interfaces), and the development of associated conformance testing architectures and testing suites designed to test for conformance to ...
Building Energy Software Tools Directory: EEM Suite
EEM Suite EEM Suite EEM Suite Logo Enables large companies to proactively monitor, analyze and manage energy costs and consumption. EEM Suite combines analysis and reporting tools; real-time, event-driven alerts; and Web-based enterprise visibility into a single solution so users can control their energy costs and usage. EEM Suite leverages meter, billing, production, real-time price, rate and weather information to drive significant energy and water reductions. Users can control utility costs through timely identification of billing errors and overcharges, drive accountability through accurate cost allocation and tenant rebilling, monitor performance against budgets, predict energy requirements to assist in key operational activities planning, improve operational efficiency through continuous facility and
Introduction to the HPC Challenge Benchmark Suite
The HPC Challenge benchmark suite has been released by the DARPA HPCS program to help define the performance boundaries of future Petascale computing systems. HPC Challenge is a suite of tests that examine the performance of HPC architectures using kernels with memory access patterns more challenging than those of the High Performance Linpack (HPL) benchmark used in the Top500 list. Thus, the suite is designed to augment the Top500 list, providing benchmarks that bound the performance of many real applications as a function of memory access characteristics e.g., spatial and temporal locality, and providing a framework for including additional tests. In particular, the suite is composed of several well known computational kernels (STREAM, HPL, matrix multiply--DGEMM, parallel matrix transpose--PTRANS, FFT, RandomAccess, and bandwidth/latency tests--b{sub eff}) that attempt to span high and low spatial and temporal locality space. By design, the HPC Challenge tests are scalable with the size of data sets being a function of the largest HPL matrix for the tested system.
Luszczek, Piotr; Dongarra, Jack J.; Koester, David; Rabenseifner,Rolf; Lucas, Bob; Kepner, Jeremy; McCalpin, John; Bailey, David; Takahashi, Daisuke
In Outer Space without a Space Suit?
The author proposes and investigates his old idea - a living human in space without the encumbrance of a complex space suit. Only in this condition can biological humanity seriously attempt to colonize space because all planets of Solar system (except the Earth) do not have suitable atmospheres. Aside from the issue of temperature, a suitable partial pressure of oxygen is lacking. In this case the main problem is how to satiate human blood with oxygen and delete carbonic acid gas (carbon dioxide). The proposed system would enable a person to function in outer space without a space suit and, for a long time, without food. That is useful also in the Earth for sustaining working men in an otherwise deadly atmosphere laden with lethal particulates (in case of nuclear, chemical or biological war), in underground confined spaces without fresh air, under water or a top high mountains above a height that can sustain respiration.
Alexander Bolonkin
SHARP: Reactor Performance and Safety Simulation Suite
SHARP SHARP Argonne National Laboratory's Reactor Performance and Safety Simulation Suite SHARP could save millions in nuclear reactor design and development... The Simulation-based High-efficiency Advanced Reactor Prototyping (SHARP) suite of codes enables virtual design and engineering of nuclear plant behavior that would be impractical from a traditional experimental approach. ...by leveraging the computational power of one of the world's most powerful supercomputers. Exploiting the power of Argonne Leadership Computing Facility's near-petascale computers, researchers have developed a set of simulation tools that provide a highly detailed description of the reactor core and the nuclear plant behavior. This enables the efficient and precise design of tomorrow's safe and clean nuclear energy sources.
Fiber Optic Velocity Interferometry
SciTech Connect
This paper explores the use of a new velocity measurement technique that has several advantages over existing techniques. It uses an optical fiber to carry coherent light to and from a moving target. A Fabry-Perot interferometer, formed by a gradient index lens and the moving target, produces fringes with a frequency proportional to the target velocity. This technique can measure velocities up to 10 km/s, is accurate, portable, and completely noninvasive.
Neyer, Barry T.
The bioenergetics of walking and running in space suits
Space-suited activity is critical for human spaceflight, and is synonymous with human planetary exploration. Space suits impose kinematic and kinetic boundary conditions that affect movement and locomotion, and in doing ...
Carr, Christopher E. (Christopher Edward), 1976-
Comparing non-adequate test suites using coverage criteria
A fundamental question in software testing research is how to compare test suites, often as a means for comparing test-generation techniques. Researchers frequently compare test suites by measuring their coverage. A coverage criterion C provides a set ... Keywords: Coverage criteria, non-adequate test suites
Milos Gligoric, Alex Groce, Chaoqiang Zhang, Rohan Sharma, Mohammad Amin Alipour, Darko Marinov
ARM - Measurement - Vertical velocity
govMeasurementsVertical velocity govMeasurementsVertical velocity ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Vertical velocity The component of the velocity vector, along the local vertical. Categories Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO2FLX : Carbon Dioxide Flux Measurement Systems ECOR : Eddy Correlation Flux Measurement System KAZR : Ka ARM Zenith Radar MMCR : Millimeter Wavelength Cloud Radar SODAR : Mini Sound Detection and Ranging
Cirrus Crystal Terminal Velocities
Cirrus crystal terminal velocities are of primary importance in determining the rate of transport of condensate from upper- to middle-tropospheric levels and profoundly influence the earthís radiation balance through their effect on the rate of ...
Andrew J. Heymsfield; Jean Iaquinta
Vertical Velocity Focus Group
Velocity Focus Group Velocity Focus Group ARM 2008 Science Team Meeting Norfolk, VA March 10-14 Background Vertical velocity measurements have been at the top of the priority list of the cloud modeling community for some time. Doppler measurements from ARM profiling radars operating at 915-MHz, 35-GHz and 94-GHz have been largely unexploited. The purpose of this new focus group is to develop vertical velocity ARM products suitable for modelers. ARM response to their request has been slow. Most ARM instruments are suitable for cloud observations and have limited capabilities in precipitation Using ARM datasets for evaluating and improving cloud parameterization in global climate models (GCMs) is not straightforward, due to gigantic scale mismatches. Consider this... Looking only vertically drastically limits opportunities
Notices Disabled, 1401 S. Clark Street, Suite
13 Federal Register 13 Federal Register / Vol. 78, No. 240 / Friday, December 13, 2013 / Notices Disabled, 1401 S. Clark Street, Suite 10800, Arlington, Virginia 22202-4149. FOR FURTHER INFORMATION CONTACT: Barry S. Lineback, Telephone: (703) 603-7740, Fax: (703) 603-0655, or email firstname.lastname@example.com. SUPPLEMENTARY INFORMATION: Addition On 6/28/2013 (78 FR 38952-38953), the Committee for Purchase From People Who Are Blind or Severely Disabled published notice of proposed addition to the Procurement List. After consideration of the material presented to it concerning capability of qualified nonprofit agency to provide the service and impact of the addition on the current or most recent contractors, the Committee has determined that the service listed below is suitable for procurement by the
A Test Suite Generator For Struts Based Applications.
??Testing web-based enterprise applications requires the use of automated testing frameworks. The testing framework's ability to run suites of test cases through development ensures enhancementsÖ (more)
Jackson, Gregory M.
Perspectives on Deposition Velocity
Deposition Deposition Velocity ... Going down the rabbit hole to explain that sinking feeling Brian DiNunno, Ph.D. Project Enhancement Corporation June 6 th , 2012 Discussion Framework ÔÇó Development of the HSS Deposition Velocity Safety Bulletin ÔÇó Broader discussion of appropriate conservatism within dispersion modeling and DOE-STD-3009 DOE-STD-3009 Dose Comparison "General discussion is provided for source term calculation and dose estimation, as well as prescriptive guidance for the latter. The intent is that calculations be based on reasonably conservative estimates of the various input parameters." - DOE-STD-3009, Appendix A.3 DOE-STD-3009 Dispersion
Improving the effectiveness of test suite reduction for user-session-based testing of web applications
Context: Test suite reduction is the problem of creating and executing a set of test cases that are smaller in size but equivalent in effectiveness to an original test suite. However, reduced suites can still be large and executing all the tests in a ... Keywords: Ordering reduced suites, Test suite prioritization, Test suite reduction, User-session-based testing, Web application testing
Sreedevi Sampath; RenÈe C. Bryce
On test suite composition and cost-effective regression testing
Regression testing is an expensive testing process used to re-validate software as it evolves. Various methodologies for improving regression testing processes have been explored, but the cost-effectiveness of these methodologies has been shown to vary with characteristics of regression test suites. One such characteristic involves the way in which test inputs are composed into test cases within a test suite. This article reports the results of controlled experiments examining the effects of two factors in test suite composition ó test suite granularity and test input grouping ó on the costs and benefits of several regression-testing-related methodologies: retest-all, regression test selection, test suite reduction, and test case prioritization. These experiments consider the application of several specific techniques, from each of these methodologies, across ten releases each of two substantial software systems, using seven levels of test suite granularity and two types of test input grouping. The effects of granularity, technique, and grouping on the cost and fault-detection effectiveness of regression testing under the given methodologies are analyzed. This analysis shows that test suite granularity significantly affects several cost-benefit factors for the methodologies considered, while test input grouping has limited effects. Further, the results expose essential tradeoffs affecting the relationship between test suite design and regression testing cost-effectiveness, with several implications for practice. 1
Gregg Rothermel; Sebastian Elbaum; Alexey Malishevsky; Praveen Kallakuri
Temporal Velocity Variations beneath the Coso Geothermal Field Observed
Velocity Variations beneath the Coso Geothermal Field Observed Velocity Variations beneath the Coso Geothermal Field Observed using Seismic Double Difference Tomography of Compressional and Shear Wave Arrival Times Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Temporal Velocity Variations beneath the Coso Geothermal Field Observed using Seismic Double Difference Tomography of Compressional and Shear Wave Arrival Times Details Activities (1) Areas (1) Regions (0) Abstract: Microseismic imaging can be an important tool for characterizing geothermal reservoirs. Since microseismic sources occur more or less continuously both due to the operations of a geothermal field and the naturally occurring background seismicity, passive seismic monitoring is well suited to quantify the temporal variations in the vicinity of a
PREVENTIVE CONSERVATION: A CONCEPT SUITED TO THE CONSERVATION OF EARTHEN ARCHITECTURAL HERITAGE and Construction Key words: Preventive conservation, traditional conservation practices, risk reduction, heritage management Abstract The concept of "preventive conservation" is relatively old as it has already been
Recanati, Catherine
The Extreme Benchmark Suite : measuring high-performance embedded systems
The Extreme Benchmark Suite (XBS) is designed to support performance measurement of highly parallel "extreme" processors, many of which are designed to replace custom hardware implementations. XBS is designed to avoid many ...
Gerding, Steven (Steven Bradley)
Building Energy Software Tools Directory: SunAngle Professional Suite
Electricity Monthly Update
Methodology and Documentation Methodology and Documentation General The Electricity Monthly Update is prepared by the Electric Power Operations Team, Office of Electricity, Renewables and Uranium Statistics, U.S. Energy Information Administration (EIA), U.S. Department of Energy. Data published in the Electricity Monthly Update are compiled from the following sources: U.S. Energy Information Administration, Form EIA-826,"Monthly Electric Utility Sales and Revenues with State Distributions Report," U.S. Energy Information Administration, Form EIA-923, "Power Plant Operations Report," fuel spot prices from Bloomberg Energy, electric power prices from SNL Energy, electric system demand data from Ventyx Energy Velocity Suite, and weather data and imagery from the National Oceanic and Atmospheric
Unitaxial constant velocity microactuator
A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-manometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment.
McIntyre, Timothy J. (Knoxville, TN)
Selecting The Optimal Logging Suite For Geothermal Reservoir Evaluation-
Selecting The Optimal Logging Suite For Geothermal Reservoir Evaluation- Selecting The Optimal Logging Suite For Geothermal Reservoir Evaluation- Results From The Alum 25-29 Well, Nevada Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Selecting The Optimal Logging Suite For Geothermal Reservoir Evaluation- Results From The Alum 25-29 Well, Nevada Details Activities (6) Areas (1) Regions (0) Abstract: This paper presents the results of analysis of a state of the art set of wireline petrophysical and wellbore image logs recorded in the Alum 25-29 well, southwestern Nevada. The Alum well penetrated nearly 2000 ft (610 m) of volcano-clastic rocks and more than 1000 ft of basement, separated from the sediments by a shallowly dipping detachment fault. The logs were acquired both to characterize the site and also to select the
Building Energy Software Tools Directory: Right-Suite Residential for
Right-Suite Residential for Windows Right-Suite Residential for Windows Right-Suite Residential for Windows logo. All-in-one HVAC software performs residential loads calculations, duct sizing, energy analysis, equipment selection, cost comparison calculations, and geothermal loop design. Also allows you to design your own custom proposals. Used for system design, for sales representation, and for quotation preparations. Buy only what you need. Unused functions are shipped as demos, so the program can grow with your needs. Keywords residential loads calculations, duct sizing, energy analysis, HVAC equipment selection, system design Validation/Testing N/A Expertise Required Knowledge of general HVAC concepts. High level of computer literacy not required. Users Over 10,000 users of Right-J loads.
Is there Lower Limit to Velocity or Velocity Change?
Here we explore the possibility of a lower limit to velocity or velocity change which is 20 orders of magnitude smaller than the speed of light and explore the various observable signatures including those in cosmic rays and gamma ray bursts.
B. N. Sreenath; Kenath Arun; C. Sivaram
A Test Suite for GCMs: An Intercomparison of 11
A Test Suite for GCMs: An Intercomparison of 11 Dynamical Cores Christiane Jablonowski1, PeterSandia National Laboratories PDEs on the Sphere Workshop, Santa Fe Apr/28/2009 #12;Motivation · Test standardized & easy-to-use analysis techniques · Idea: Establish a collection of test cases that finds broad
Jablonowski, Christiane
Polysemy and sense proximity in the Senseval-2 test suite
We report on an empirical study of sense relations in the Senseval-2 test suite. We apply and extend the method described in (Resnik and Yarowsky, 1999), estimating proximity of sense pairs from the evidence collected from native-speaker translations ...
Irina Chugur; Julio Gonzalo; Felisa Verdejo
DYNA3D/ParaDyn Regression Test Suite Inventory
The following table constitutes an initial assessment of feature coverage across the regression test suite used for DYNA3D and ParaDyn. It documents the regression test suite at the time of production release 10.1 in September 2010. The columns of the table represent groupings of functionalities, e.g., material models. Each problem in the test suite is represented by a row in the table. All features exercised by the problem are denoted by a check mark in the corresponding column. The definition of ''feature'' has not been subdivided to its smallest unit of user input, e.g., algorithmic parameters specific to a particular type of contact surface. This represents a judgment to provide code developers and users a reasonable impression of feature coverage without expanding the width of the table by several multiples. All regression testing is run in parallel, typically with eight processors. Many are strictly regression tests acting as a check that the codes continue to produce adequately repeatable results as development unfolds, compilers change and platforms are replaced. A subset of the tests represents true verification problems that have been checked against analytical or other benchmark solutions. Users are welcomed to submit documented problems for inclusion in the test suite, especially if they are heavily exercising, and dependent upon, features that are currently underrepresented.
Lin, J I
Measurement of the propagation velocity of single plasma channels in a spark chamber for particle track detection
The velocity of growth of single tracks in a spark chamber is described. It is shown thai in the pressure range 300 < p < 760 torr the tracks propagate with the same velocity to the anode and cathode provided that E/p remains below an experimentally determined value. A rise of this value causes an asymmetry, which makes the chamber no longer suited for the track localization of ionizing particles. (GE)
Timm, U.
ARM - Measurement - Hydrometeor fall velocity
fall velocity fall velocity ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor fall velocity Fall velocity of hydrometeors (e.g. rain, snow, graupel, hail). Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments DISDROMETER : Impact Disdrometer LDIS : Laser Disdrometer WSACR : Scanning ARM Cloud Radar, tuned to W-Band (95GHz) Field Campaign Instruments DISDROMETER : Impact Disdrometer PDI : Phase Doppler Interferometer
The Extreme Benchmark Suite: Measuring High-Performance Embedded Systems
The Extreme Benchmark Suite (XBS) is designed to support performance measurement of highly parallel ìextreme î processors, many of which are designed to replace custom hardware implementations. XBS is designed to avoid many of the problems that occur when using existing benchmark suites with nonstandard and experimental architectures. In particular, XBS is intended to provide a fair comparison of a wide range of architectures, from general-purpose processors to hard-wired ASIC implementations. XBS has a clean modular structure to reduce porting effort, and is designed to be usable with slow cycle-accurate simulators. This work presents the motivation for the creation of XBS and describes in detail the XBS framework. Several benchmarks implemented with this framework are discussed, and these benchmarks are used to compare a standard platform, an experimental architecture, and custom
Steven Gerding; Krste Asanovi?
Revel8or: Model Driven Capacity Planning Tool Suite
Designing complex multi-tier applications that must meet strict performance requirements is a challenging software engineering problem. Ideally, the application architect could derive accurate performance predictions early in the project life-cycle, leveraging initial application design-level models and a description of the target software and hardware platforms. To this end, we have developed a capacity planning tool suite for component-based applications, called Revel8tor. The tool adheres to the model driven development paradigm and supports benchmarking and performance prediction for J2EE, .Net and Web services platforms. The suite is composed of three different tools: MDAPerf, MDABench and DSLBench. MDAPerf allows annotation of design diagrams and derives performance analysis models. MDABench allows a customized benchmark application to be modeled in the UML 2.0 Testing Profile and automatically generates a deployable application, with measurement automatically conducted. DSLBench allows the same benchmark modeling and generation to be conducted using a simple performance engineering Domain Specific Language (DSL) in Microsoft Visual Studio. DSLBench integrates with Visual Studio and reuses its load testing infrastructure. Together, the tool suite can assist capacity planning across platforms in an automated fashion.
Zhu, Liming; Liu, Yan; Bui, Ngoc B.; Gorton, Ian
Experimental Techniques for Measuring Temperature and Velocity...
Measuring Temperature and Velocity Fields to Improve the Use and Validation of Building Heat Transfer Models Title Experimental Techniques for Measuring Temperature and Velocity...
The Velocity-Selecting Cerenkov Counter
BAFFLE VELOCITY - SELECTING CERENKOV COUNTER (C 2) FiJI. 1velocity-selectinp: Cerenkov counter. ueaL-31;S CYLINDRICA~
Chamberlain, Owen; Weigand, Clyde
PHAST (PHAGE ASSEMBLY SUITE AND TUTORIAL): A WEB-BASED GENOME as genome assembly. PHAST (Phage Assembly Suite and Tutorial) is an online set small phage genomes of their own. With PHAST, entry-level biology students learn
Campbell, A. Malcolm
Robotic Joint Torque Testing: A Critical Tool in the Development of Pressure Suit Mobility Elements
Pressure suits allow pilots and astronauts to survive in extreme environments at the edge of Earthís atmosphere and in the vacuum of space. One obstacle that pilots and astronauts face is that gas-pressurized suits stiffen ...
Meyen, Forrest Edward
Space suit simulator for partial gravity extravehicular activity experimentation and training
During human space exploration, mobility is extremely limited when working inside a pressurized space suit. Astronauts perform extensive training on Earth to become accustomed to space suit-imposed high joint torques and ...
Gilkey, Andrea L. (Andrea Lynn)
Velocity Distributions from Nonextensive Thermodynamics
There is no accepted mechanism that explains the equilibrium structures that form in collisionless cosmological N-body simulations. Recent work has identified nonextensive thermodynamics as an innovative approach to the problem. The distribution function that results from adopting this framework has the same form as for polytropes, but the polytropic index is now related to the degree of nonextensiveness. In particular, the nonextensive approach can mimic the equilibrium structure of dark matter density profiles found in simulations. We extend the investigation of this approach to the velocity structures expected from nonextensive thermodynamics. We find that the nonextensive and simulated N-body rms-velocity distributions do not match one another. The nonextensive rms-velocity profile is either monotonically decreasing or displays little radial variation, each of which disagrees with the rms-velocity distributions seen in simulations. We conclude that the currently discussed nonextensive models require further modifications in order to corroborate dark matter halo simulations. (adapted from TeX)
Eric I. Barnes; Liliya L. R. Williams; Arif Babul; Julianne J. Dalcanton
Creating suites of models with system entity structure: global warming example
We describe how to develop a suite of models in the MS4 Modeling Environment. The approach employs the operation of merging of System Entity Structures supported by the environment. After construction, the suite of models can be hosted on Model Store, ... Keywords: component-based modeling, suite of models, system entity structure, systems of systems
Bernard P. Zeigler, Chungman Seo, Robert Coop, Doohwan Kim
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.
Integration of APECS and VE-Suite for Data Overlay
In the design of advanced power generation facilities, process simulation tools are being utilized to model plant behavior and quickly analyze results. While such tools enable investigation of crucial aspects of plant design, typical commercial process simulators still do not explore some plant design information, including high-fidelity data from computational fluid dynamics (CFD) models of complex thermal and fluid flow phenomena, economics data used for policy decisions, operational data after the plant is constructed, and as-built information for use in as-designed models. Software tools must be created that allow disparate sources of information to be integrated for facilitating accurate and effective plant design. At the Department of Energyís (DOE) National Energy Technology Laboratory (NETL), the Advanced Process Engineering Co-Simulator (APECS) has been developed as an integrated software suite that combines process simulation (e.g., Aspen PlusÆ) and high-fidelity equipment simulation (e.g., FLUENTÆ). In this paper, the integration of the high-fidelity CFD data with overall process data in a virtual power simulation environment will be described. More specifically, we will highlight VE-Suite, an open-source virtual engineering (VE) software toolkit, and its support of Aspen PlusÆ Hierarchy blocks via the VE-AspenUnit.
McCorkel, Doug (Iowa State University, Ames, IA); Bivins, Gerrick (Iowa State University, Ames, IA); Jordan, Terry; Bryden, Mark (Iowa State University, Ames, IA); Zitney, S.E.; Widmann, John (ANSYS, Lebanon, NH); Osawe, Maxwell
User Guide for the STAYSL PNNL Suite of Software Tools
The STAYSL PNNL software suite provides a set of tools for working with neutron activation rates measured in a nuclear fission reactor, an accelerator-based neutron source, or any neutron field to determine the neutron flux spectrum through a generalized least-squares approach. This process is referred to as neutron spectral adjustment since the preferred approach is to use measured data to adjust neutron spectra provided by neutron physics calculations. The input data consist of the reaction rates based on measured activities, an initial estimate of the neutron flux spectrum, neutron activation cross sections and their associated uncertainties (covariances), and relevant correction factors. The output consists of the adjusted neutron flux spectrum and associated covariance matrix, which is useful for neutron dosimetry and radiation damage calculations.
Greenwood, Lawrence R.; Johnson, Christian D.
MDM Project: Analysis of the Micromechanics Damage Model Suite
This report extends a previous study of core algorithms and portability considerations associated with the Micromechanics Damage Model computer software developed by the AFRL Materials Directorate at Wright-Patterson Air Force Base. 1 The MDM analysis suite is comprised of four fracture mechanics codes used to establish design criteria for newly developed composite materials, particularly for brittle, heat-resistant composites associated with the fabrication of turbine blades. The MDM codes are based on a semi-analytical approach in which single coated fibers and the surrounding composite material are represented as a nested set of concentric shells (Fig. 1). Stresses and displacements at prescribed points along the length of the cylinder are determined by evaluation of a polynomial function. Numerically challenging conditions arise during the construction of this function. The calculation of matrix exponentials in terms of the full spectrum of eigenvalues associated with the pri...
D. C. O' neal; R. Luczak; N. J. Pagano; H. W. Brown Iii; G. P. Tandon
DOE Workshop - Deposition Velocity Status
Delivering DOE's Vision for the Delivering DOE's Vision for the East Tennessee Technology Park Mission Safely Delivering the Department of Energy's Vision for the East Tennessee Technology Park Mission DOE Workshop Deposition Velocity Status Mike Hitchler, Manager Nuclear Facility Safety June 5, 2012 Safely Delivering DOE's Vision for the East Tennessee Technology Park Mission Existing UCOR Analyses * UCOR facilities at East Tennessee Technology Park (ETTP) and Oak Ridge National Laboratory (ORNL) use various plume models depending on when they were developed and by whom. - Some use MACCS or MACCS2 for dispersion evaluation. (~5 locations) - LLLW uses ingestion modeling (multiple locations)
Equatorial Velocity Profiles. Part II: Zonal Component
Vertical profiles of horizontal velocity made along 53∞E in the western Indian Ocean, during and after he onset of the southwest monsoon in 1976, show features in zonal velocity of relatively small vertical scale. Persistence of the features over ...
Kathleen O'Neill; James R. Luyten
An Acoustic Doppler and Electromagnetic Velocity Profiler
A freely failing current meter called the Absolute Velocity Profiler (AVP) is described. This profiler is an expansion of a previously developed instrument, the Electro-Magnetic Velocity Profiler (EMVP), with the additional capability of acoustic ...
Thomas B. Sanford; Robert G. Driver; John H. Dunlap
Velocity Probability Density Functions for Oceanic Floats
Probability density functions (PDFs) of daily velocities from subsurface floats deployed in the North Atlantic and equatorial Atlantic Oceans are examined. In general, the PDFs are approximately Gaussian for small velocities, but with significant ...
Annalisa Bracco; J. H. LaCasce; Antonello Provenzale
Equatorial Velocity Profiles. Part I: Meridional Component
A time series or vertical profiles of horizontal velocity was collected in the western equatorial Indian Ocean during late spring of 1976. The meridional velocity component is examined here, the zonal component in Part II of this paper. The ...
Kathleen O'Neill
Waterspout Velocity Measurements by Airborne Doppler Lidar
A Doppler lidar measures the line-of-sight velocity of cloud droplets in a waterspout much as a meteorological Doppler radar measures the velocity of larger hydrometeors. We discuss details of the application of an airborne Doppler lidar to ...
R. L. Schwiesow; R. E. Cupp; P. C. Sinclair; R. F. Abbey Jr.
Velocity Probability Density Functions from Altimetry
Probability density functions (pdfs) are employed to evaluate the distribution of velocities in the global ocean. This study computes pdfs of ocean surface velocity using altimetric data from the TOPEX/Poseidon satellite. Results show that the ...
Sarah T. Gille; Stefan G. Llewellyn Smith
Determining Velocities and Mixing Coefficients from Tracers
The effort to determine oceanic velocities from tracer distributions relies on a knowledge of the effects of mixing. However, the macroscopic diffusion coefficient, K, is generally not known and must be calculated along with the velocity. The ...
Jae Hak Lee; George Veronis
Determining Vertical Water Velocities from Seaglider
Vertical velocities in the worldís oceans are typically small, less than 1 cm s?1, posing a significant challenge for observational techniques. Seaglider, an autonomous profiling instrument, can be used to estimate vertical water velocity in the ...
Eleanor Frajka-Williams; Charles C. Eriksen; Peter B. Rhines; Ramsey R. Harcourt
Traditional And Angle-dependent Characterization Of Penn Stateís Panel Transmission Loss Suite.
??The Center for Acoustics and Vibration at Penn State has a Panel Transmission Loss Suite consisting of a reverberation chamber coupled to an anechoic room.Ö (more)
Bauch, Paul
Analysis of Thermostat Design for Vertical Fan Coil Units Within Modern Window-Wall Condominium Suites.
??The aim for this research is to identify the issues with poor thermostat designs in a window-wall condominium suite during cooling season, and to investigateÖ (more)
Ruff, Shawn
An indicator is presented for measuring the lowspeed velocity of an object in one direction where the object returns in the opposite direction at a high speed. The indicator comprises a drum having its axis of rotation transverse to the linear movement of the object and a tape wound upon the drum with its free end extending therefrom and adapted to be connected to the object. A constant torque is applied to the drum in a direction to wind the tape on the drum. The speed of the tape in the unwinding direction is indicated on a tachometer which is coupled through a shaft and clutch means to the drum only when the tape is unwinding.
Digney, F.J. Jr.; Bevilacqua, F.
Fault-based test suite prioritization for specification-based testing
Context: Existing test suite prioritization techniques usually rely on code coverage information or historical execution data that serve as indicators for estimating the fault-detecting ability of test cases. Such indicators are primarily empirical in ... Keywords: Fault class hierarchy, Fault-based prioritization, Fault-based testing, Software testing, Specification-based testing, Test suite prioritization
Yuen Tak Yu; Man Fai Lau
Evaluation of Sediment Toxicity Using a Suite of Assessment Tools
Accurate characterization of risk of adverse ecological effects related to contaminated sediment presents a particularly difficult challenge. A series of studies has been conducted to investigate the utility of various tools for assessment of sediment toxicity. The goal of this research was to provide information which could help increase the accuracy with which predictions of toxicity could be made at hazardous sites. A calibration study was conducted using model PAHs, PCBs, a binary PAH mixture and a coal-tar mixture. This study was a collaborative effort among five university-based Superfund Research Programs (SRPs). Each program, with the help of funding through the NIEHS Superfund Research Program, has developed a chemical-class specific assay to estimate toxicity of contaminants in sediment. This suite of bioassays expands the range of data typically obtained through the use of standard aquatic toxicity assays. A series of caged in situ exposure studies has been conducted using juvenile Chinook salmon and Pacific staghorn sculpin in the Lower Duwamish Waterway. The study aimed to investigate the utility of selected biomarkers in evaluating the relationship between contaminants present in environmental samples and response in receptors following an in situ caged exposure. Results found that DNA adducts detected in exposed fish were significantly higher than controls in 2004 and 2006, and DNA adducts appear to be a reliable indicator of exposure, although no dose-response relationship was present. Western blot analysis of CYP1A1 was not indicative of exposure levels. The final study conducted was concerned with evaluating the utility of using solid phase microextraction (SPME) fibers in situ to evaluate contaminated sediment. Levels of PAHs and PCBs in sediment often exceeded sediment quality guidelines; however, results from aquatic toxicity bioassays using Hyalella azteca were mostly negative, thus levels of contaminants detected on SPME fibers could not be associated with adverse effects in Hyalella. However, regression analysis of total PAHs present in sediment and levels of PAHs detected in porewater SPME fiber samplers, which were placed 5 cm into the sediment for 30 days, revealed a strongly correlated linear relationship (R2 = .779). Normalization of the sediment data to total organic carbon was performed to determine if the trend would remain present, and the linear relationship was again confirmed (R2 =.709).
Kelley, Matthew A
Influence of the inlet velocity profiles on the prediction of velocity distribution inside an electrostatic precipitator
The influence of the velocity profile at the inlet boundary on the simulation of air velocity distribution inside an electrostatic precipitator is presented in this study. Measurements and simulations were performed in a duct and an electrostatic precipitator (ESP). A four-hole cobra probe was used for the measurement of velocity distribution. The flow simulation was performed by using the computational fluid dynamics (CFD) code FLUENT. Numerical calculations for the air flow were carried out by solving the Reynolds-averaged Navier-Stokes equations coupled with the realizable k-{epsilon} turbulence model equations. Simulations were performed with two different velocity profiles at the inlet boundary - one with a uniform (ideal) velocity profile and the other with a non-uniform (real) velocity profile to demonstrate the effect of velocity inlet boundary condition on the flow simulation results inside an ESP. The real velocity profile was obtained from the velocity measured at different points of the inlet boundary whereas the ideal velocity profile was obtained by calculating the mean value of the measured data. Simulation with the real velocity profile at the inlet boundary was found to predict better the velocity distribution inside the ESP suggesting that an experimentally measured velocity profile could be used as velocity inlet boundary condition for an accurate numerical simulation of the ESP. (author)
Haque, Shah M.E.; Deev, A.V.; Subaschandar, N. [Process Engineering and Light Metals (PELM) Centre, Faculty of Sciences, Engineering and Health, Central Queensland University, Gladstone, Queensland 4680 (Australia); Rasul, M.G.; Khan, M.M.K. [College of Engineering and Built Environment, Faculty of Sciences, Engineering and Health, Central Queensland University, Rockhampton, Queensland 4702 (Australia)
Rooftop Unit Suite: RTU Challenge, RTU Advanced Controls and RTU Smart Monitoring and Diagnostic System
Suite of Projects Suite of Projects RTU Suite: RTU Challenge, RTU Advanced Controls and RTU Smart Monitoring and Diagnostic System Michael Brambley, Ph.D. Pacific Northwest National Laboratory email@example.com (509) 375-6875 April 4, 2013 2 | Building Technologies Office eere.energy.gov * Packaged air conditioners and heat pumps (RTUs) are used in about 58% of all cooled commercial buildings, serving about 69% of the cooled commercial building floor space (EIA 2003) - Navigant estimates that packaged air conditioners
A Benchmark Suite for Evaluating the Performance of the WebODE Ontology Engineering Platform
Abstract. Ontology tools play a key role in the development and maintenance of the Semantic Web. Hence, we need in one hand to objectively evaluate these tools, in order to analyse whether they can deal with actual and future requirements, and in the other hand to develop benchmark suites for performing these evaluations. In this paper, we describe the method we have followed to design and implement a benchmark suite for evaluating the performance of the WebODE ontology engineering workbench, along with the conclusions obtained after using this benchmark suite for evaluating WebODE. 1.
Ra˙l GarcÌa-castro; AsunciÛn GÛmez-pÈrez
Impact Velocity (2011) | National Nuclear Security Administration
National Nuclear Security Administration (NNSA)
Impact Velocity (2011) | National Nuclear Security Administration Impact Velocity (2011) | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > Media Room > Video Gallery > Impact Velocity (2011) Impact Velocity (2011) Impact Velocity (2011) From: NNSANews Views: 388 2 ratings Time: 02:26 More in Science & Technology See video Facebook Twitter
The velocity campaign for ignition on NIF
Achieving inertial confinement fusion ignition requires a symmetric, high velocity implosion. Experiments show that we can reach 95 {+-} 5% of the required velocity by using a 420 TW, 1.6 MJ laser pulse. In addition, experiments with a depleted uranium hohlraum show an increase in capsule performance which suggests an additional 18 {+-} 5 {mu}m/ns of velocity with uranium hohlraums over gold hohlraums. Combining these two would give 99 {+-} 5% of the ignition velocity. Experiments show that we have the ability to tune symmetry using crossbeam transfer. We can control the second Legendre mode (P2) by changing the wavelength separation between the inner and outer cones of laser beams. We can control the azimuthal m = 4 asymmetry by changing the wavelength separation between the 23.5 and 30 degree beams on NIF. This paper describes our 'first pass' tuning the implosion velocity and shape on the National Ignition Facility laser [Moses et al., Phys. Plasmas, 16, 041006 (2009)].
Callahan, D. A.; Meezan, N. B.; Glenzer, S. H.; MacKinnon, A. J.; Benedetti, L. R.; Bradley, D. K.; Celeste, J. R.; Celliers, P. M.; Dixit, S. N.; Doeppner, T.; Dzentitis, E. G.; Glenn, S.; Haan, S. W.; Haynam, C. A.; Hicks, D. G.; Hinkel, D. E.; Jones, O. S.; Landen, O. L.; London, R. A.; MacPhee, A. G. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others
A Comparison of Meteorological Observations from South Pole Station before and after Installation of a New Instrument Suite
The AmundsenñScott South Pole surface meteorological instrument suite was upgraded in 2004. To ensure that the new and old instruments were recording similar information, the two suites of instruments ran simultaneously for a year. Statistical ...
L. M. Keller; K. A. Baker; M. A. Lazzara; J. Gallagher
Liner velocity, current, and symmetry measurements on the 32 MEGAMP flux compression generator experiment ALT-1
A flux compression generator pulse power system, designed, built, and fielded by a Russian team at the All Russian Scientific Research Institute of Experimental Physics (VNIIEF), was used to successfully drive an aluminum liner to velocities greater than 12 km/sec. The experiment objective was to demonstrate performance of a precision liner implosion at an Atlas current of 30 MA or greater. Diagnostics to measure liner performance were an essential part of the experiment. An experimental team from Los Alamos National Laboratory (LANL) provided a suite of diagnostics to measure liner performance. Three diagnostics were fielded: (1) A velocity interferometer (VISAR) to continuously measure the liner innersurface velocity throughout the entire range of travel, (2) Two Faraday rotation devices to measure liner current during the implosion, and, (3) Sixteen fiber optic impact pins to record liner impact time and provide axial and azimuthal symmetry information. All diagnostics performed very well. Major results are maximum current: 32.3 MA, velocity at impact: greater than 12 km/sec, symmetry: the impact pins indicated that the liner was smooth, solid, and axially symmetric upon arrival at the diagnostic package. The LANL team fabricated, installed, and recorded the three diagnostics presented here. All necessary equipment was brought to the site in Russia. The VNIIEF team fielded other diagnostics to measure machine performance. Results of machine diagnostics are reported in other presentations.
Anderson, B. G. (Brodie G.); Rodriguez, G. (George); Stokes, J. L. (John L.); Tabaka, L. J. (Leonard J.); Clark, D. A. (David A.)
Development of a mechanical counter pressure Bio-Suit System for planetary exploration
Extra-vehicular activity (EVA) is critical for human spaceflight and particularly for human planetary exploration. The MIT Man Vehicle Laboratory is developing a Bio-Suit EVA System, based on mechanical counterpressure ...
Sim, Zhe Liang
DC Pro Software Tool Suite, Data Center Fact Sheet, Industrial Technologies Program
This fact sheet describes how DOE's Data Center Energy Profiler (DC Pro) Software Tool Suite and other resources can help U.S. companies identify ways to improve the efficiency of their data centers.
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OLENDER REPORTING, INC. 1100 Connecticut Ave., NW, Suite 810, Washington, DC
100 Connecticut Ave., NW, Suite 810, Washington, DC 100 Connecticut Ave., NW, Suite 810, Washington, DC 20036 Washington: (202) 898-1108 / Baltimore: (410) 752-3376 Toll Free: (888) 445-3376 1 Electricity Advisory Committee Meeting 8:33 a.m. through 2:49 p.m. October 29, 2010 OLENDER REPORTING, INC. 1100 Connecticut Ave., NW, Suite 810, Washington, DC 20036 Washington: (202) 898-1108 / Baltimore: (410) 752-3376 Toll Free: (888) 445-3376 2 National Rural Electric Cooperative Conference Center 4301 Wilson Boulevard Arlington, VA 22203 OLENDER REPORTING, INC. 1100 Connecticut Ave., NW, Suite 810, Washington, DC 20036 Washington: (202) 898-1108 / Baltimore: (410) 752-3376 Toll Free: (888) 445-3376 3 ELECTRICITY ADVISORY MEMBERS PRESENT: Richard Cowart
Fleet-Wide Prognostic and Health Management Suite: Beta Testing Results
The Fleet-Wide Prognostic and Health Management software suite (FW-PHM) is an integrated suite of web-based diagnostic and prognostic tools and databases specifically developed for the Electric Power Research Institute by Expert Microsystems for use in the commercial power industry (both nuclear and fossil fuel). FW-PHM serves as an integrated health management framework, managing the functionality needed for a complete implementation of automated diagnostics and prognostics. The open-architecture ...
Chromospheric Doppler Velocity Oscillations in a Sunspot
We analyse the chromospheric Doppler velocity oscillations in a sunspot using the high resolution spectral observations obtained from the Fast Imaging Solar Spectrograph(FISS) of the New Solar Telescope at the Big Bear Solar Observatory. The Doppler velocity maps are constructed from the bisectors of the spectral observations. The time series analysis of Doppler velocity maps show enhanced power in the sunspot umbra at higher frequencies and in the penumbra at lower frequencies. We find that the peak power frequency decreases gradually from the umbra to outward.
Maurya, R A
Estimating Spatial Velocity Statistics with Coherent Doppler Lidar
The spatial statistics of a simulated turbulent velocity field are estimated using radial velocity estimates from simulated coherent Doppler lidar data. The structure functions from the radial velocity estimates are processed to estimate the ...
Rod Frehlich; Larry Cornman
More on Finding a Single Number to Indicate Overall Performance of a Benchmark Suite
The topic of finding a single number to summarize overall performance over a benchmark suite is continuing to be a difficult issue 14 years after Smithís paper [1]. While significant insight into the problem has been provided by Smith [1], Hennessey and Patterson [2], Cragon [3], etc, the research community still seems to be unclear on the correct mean to use for different performance metrics. How should metrics obtained from individual benchmarks be aggregated to present a summary of the performance over the entire suite? What are valid central tendency measures over the whole benchmark suite for speedup, CPI, IPC, MIPS, MFLOPS, cache miss rates, cache hit rates, branch misprediction rates, etc? Arithmetic mean has been touted to be appropriate for
Lizy Kurian John
Description of sprays using joint hyperbolic distribution in particle size and velocity
The joint probability density functions of droplet size and velocity have been represented in sprays by the two-dimensional hyperbolic distribution. A distribution is provided, and a procedure to compute its eight parameters outlined. Analytical expressions for certain statistical quantities, such as mean diameters, momentum, kinetic energy etc., applicable under certain restrictions, are obtained. The computations for a water spray issuing from a Danfoss 60{degrees} solid cone oil-burner nozzle demonstrate not only that the hyperbolic distribution provides an excellent approximation for the joint size and velocity distributions for the measurements taken along the entire length of the spray axis, but also that such representation presents a clear insight into the physics of the motion and the related size formation. The computations reveal a developing region, with areas dominated by breakup or coalescence of droplets, followed by a developed state with little change in droplet size but continuously decreasing velocity. It is concluded that this novel approach is well suited to the description of sprays.
Bhatia, J.C.; Durst, F. (LSTM-Erlangen, Lehrstuhl fur Stromungsmechanik, Universitat Erlangen-Nurnberg, 8520 Erlangen (DE))
ARM - Evaluation Product - Convective Vertical Velocity
ProductsConvective Vertical Velocity ProductsConvective Vertical Velocity Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Convective Vertical Velocity 2011.04.25 - 2011.05.23 Site(s) SGP General Description Convective processes play an important role in Earth's energy balance by distributing heat and moisture throughout the atmosphere. In particular, vertical air motions associated with these processes are inherently linked to the life cycle of these convective systems and are therefore directly tied to their energy budget. However, direct measurements of vertical air motions (e.g., in situ aircraft observations) are sparse, making it difficult to compare them with numerical model output, which relies on convective parameterization schemes that have yet to be extensively
Visibility graph analysis of solar wind velocity
We analyze in situ measurements of solar wind velocity obtained by Advanced Composition Explorer (ACE) spacecraft and Helios spacecraft during the years 1998-2012 and 1975-1983 respectively. The data belong to mainly solar cycle 23 (1996-2008) and solar cycle 21 (1976-1986) respectively. We use Directed Horizontal Visibility graph (DHVg) algorithm and estimate a graph functional, namely, the degree distance (D) as the Kullback-Leibler divergence (KLD) argument to understand time irreversibility of solar wind time series. We estimate this degree distance irreversibility parameter for these time series at different phases of solar activity cycle. Irreversibility parameter is first established for known dynamical data and then applied for solar wind velocity time series. It is observed that irreversibility in solar wind velocity fluctuations show similar behaviour at 0.3 AU (Helios data) and 1 AU (ACE data). Moreover it changes over the different phases of solar activity cycle.
Suyal, Vinita; Singh, Harinder P
Impact of Hight Velocity Cold Spray Particles
This paper presents experimental data and an computational model of the cold spray solid particle impact process. Copper particles impacting onto a polished stainless steel substrate are examined. The high velocity impact causes significant plastic deformation of both the particle and the sub- strate, but no melting is observed. The plastic deformation exposes clean surfaces that, under the high impact pressures, result in significant bond strengths between the particle and substrate. Experimental measurements of the splat and crater sizes compare well with the numerical calculations. It is shown that the crater depth is significant and increases with impact velocity. However, the splat diameter is much less sensitive to the impact velocity. It is also shown that the geometric lengths of the splat and crater scale linearly with the diameter of the impacting particle. It is hoped that the results presented will allow better understanding of the bonding process during cold spray.
Dykhuizen, R.C.; Gilmore, D.L.; Jiang, X.; Neiser, R.A.; Sampath, S.; Smith, M.F.
Aggregate Terminal Velocity/Temperature Relations
Terminal velocities of snow aggregates in storms along the Front Range in eastern Colorado are examined with a ground-based two-dimensional video disdrometer. Power-law relationships for particles having equivalent volume diameters of 0.5ñ20 mm ...
Edward A. Brandes; Kyoko Ikeda; Gregory Thompson; Michael Schˆnhuber
Vehicle Velocity Estimation Based on RSS Measurements
This paper presents a technique which is based on pattern recognition techniques, in order to estimate Mobile Terminal (MT) velocity. The proposed technique applies on received signal strength (RSS) measurements and more precisely on information extracted ... Keywords: HIDden Markov Model, WCDMA, clustering, location based services, pattern recognition, propagation modeling, traffic information
Theodore S. Stamoulakatos; Antonis S. Markopoulos; Miltiadis E. Anagnostou; Michalis E. Theologou
Minimizing test suites in software product lines using weight-based genetic algorithms
Test minimization techniques aim at identifying and eliminating redundant test cases from test suites in order to reduce the total number of test cases to execute, thereby improving the efficiency of testing. In the context of software product line, ... Keywords: fault detection capability, feature pairwise coverage, test minimization, weight-based gas
Shuai Wang; Shaukat Ali; Arnaud Gotlieb
On Test Suite Composition and Cost-Effective Regression Testing. Gregg Rothermel
On Test Suite Composition and Cost-Effective Regression Testing. Gregg Rothermel , Sebastian firstname.lastname@example.com August 30, 2003 Abstract Regression testing is an expensive testing process used to re-validate software as it evolves. Various methodologies for improving regression testing processes have been explored, but the cost
Rothermel, Gregg
On Test Suite Composition and Cost-Effective Regression Testing Gregg Rothermel
On Test Suite Composition and Cost-Effective Regression Testing Gregg Rothermel , Sebastian firstname.lastname@example.com August 31, 2004 Abstract Regression testing is an expensive testing process used to re-validate software as it evolves. Various methodologies for improving regression testing processes have been explored, but the cost
VAMPIRE microarray suite: a web-based platform for the interpretation of gene expression data
the increased computational load. Since all of these transactions are stored in the VAMPIRE database, no dataVAMPIRE microarray suite: a web-based platform for the interpretation of gene expression data of analysis, collectively known as variance-modeled posterior inference with regional exponentials (VAMPIRE
Hydrogen Storage Systems Analysis Meeting 955 L'Enfant Plaza North, SW, Suite 6000
Hydrogen Storage Systems Analysis Meeting 955 L'Enfant Plaza North, SW, Suite 6000 Washington, DC, 2005 #12;SUMMARY REPORT Hydrogen Storage Systems Analysis Meeting March 29, 2005 955 L'Enfant Plaza was to familiarize the DOE research community involved in hydrogen storage materials and process development
An overview of the HDF5 technology suite and its applications
In this paper, we give an overview of the HDF5 technology suite and some of its applications. We discuss the HDF5 data model, the HDF5 software architecture and some of its performance enhancing capabilities. Keywords: HDF5, data management, data models, databases
Mike Folk; Gerd Heber; Quincey Koziol; Elena Pourmal; Dana Robinson
On the theory of turbulent flame velocity
The renormalization ideas of self-similar dynamics of a strongly turbulent flame front are applied to the case of a flame with realistically large thermal expansion of the burning matter. In that case a flame front is corrugated both by external turbulence and the intrinsic flame instability. The analytical formulas for the velocity of flame propagation are obtained. It is demonstrated that the flame instability is of principal importance when the integral turbulent length scale is much larger than the cut off wavelength of the instability. The developed theory is used to analyse recent experiments on turbulent flames propagating in tubes. It is demonstrated that most of the flame velocity increase measured experimentally is provided by the large scale effects like the flame instability, and not by the small-scale external turbulence.
Vitaly Bychkov; Vyacheslav Akkerman; Arkady Petchenko
Black suit with a white, button down, collared dress shirt and conservative tie Black socks and black shoes
Dress Code Men · Black suit with a white, button down, collared dress shirt and conservative tie · Black socks and black shoes Women · Black dress, black suit pant or skirt (dress or skirt must be at or below the knee) · Black hose (without pattern) and black dress shoes MSC OPAS provides: · A volunteer
Boas, Harold P.
High-Velocity Rocks Final Report
DOE Green Energy (OSTI)
The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal applications by inserting into this report a small part of the interpretation we have done with 3C3D data across Wister geothermal field in the Imperial Valley of California. This interpretation shows that P-SV data reveal faults (and by inference, also fractures) that cannot be easily, or confidently, seen with P-P data, and that the combination of P-P and P-SV data allows VP/VS velocity ratios to be estimated across a targeted reservoir interval to show where an interval has more sandstone (the preferred reservoir facies). The conclusion reached from this investigation is that S-wave seismic technology can be invaluable to geothermal operators. Thus we developed a strong interest in understanding the direct-S modes produced by vertical-force sources, particularly vertical vibrators, because if it can be demonstrated that direct-S modes produced by vertical-force sources can be used as effectively as the direct-S modes produced by horizontal-force sources, geothermal operators can acquire direct-S data across many more prospect areas than can be done with horizontal-force sources, which presently are limited to horizontal vibrators. We include some of our preliminary work in evaluating direct-S modes produced by vertical-force sources.
Hardage, Bob A; DeAngelo, Michael V; Ermolaeva, Elena; Hardage, Bob A; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion
A.: Defining a benchmark suite for evaluating the import of OWL lite ontologies
Abstract. Semantic Web tools should be able to correctly interchange ontologies and, therefore, to interoperate. This interchange is not always a straightforward task if tools have different underlying knowledge representation paradigms. This paper describes the process followed to define a benchmark suite for evaluating the OWL import capabilities of ontology development tools in a benchmarking activity in progress in the Knowledge Web 1 European Network of Excellence. 1
Stefano David; Ra˙l GarcÌa-castro; AsunciÛn GÛmez-pÈrez
Towards the Integration of APECS and VE-Suite for Virtual Power Plant Co-Simulation
Process modeling and simulation tools are widely used for the design and operation of advanced power generation systems. These tools enable engineers to solve the critical process systems engineering problems that arise throughout the lifecycle of a power plant, such as designing a new process, troubleshooting a process unit or optimizing operations of the full process. To analyze the impact of complex thermal and fluid flow phenomena on overall power plant performance, the Department of Energyís (DOE) National Energy Technology Laboratory (NETL) has developed the Advanced Process Engineering Co-Simulator (APECS). The APECS system is an integrated software suite that combines process simulation (e.g., Aspen Plus) and high-fidelity equipment simulations such as those based on computational fluid dynamics (CFD), together with advanced analysis capabilities including case studies, sensitivity analysis, stochastic simulation for risk/uncertainty analysis, and multi-objective optimization. In this paper we discuss the initial phases of the integration of the APECS system with the immersive and interactive virtual engineering software, VE-Suite, developed at Iowa State University and Ames Laboratory. VE-Suite uses the ActiveX (OLE Automation) controls in the Aspen Plus process simulator wrapped by the CASI library developed by Reaction Engineering International to run process/CFD co-simulations and query for results. This integration represents a necessary step in the development of virtual power plant co-simulations that will ultimately reduce the time, cost, and technical risk of developing advanced power generation systems.
Zitney, S.E.; McCorkle, D. (Iowa State University, Ames, IA); Yang, C. (Reaction Engineering International, Salt Lake City, UT); Jordan, T.; Swensen, D. (Reaction Engineering International, Salt Lake City, UT); Bryden, M. (Iowa State University, Ames, IA)
Unexplored Aspect of Velocity of light
In the post-Maxwellian era, sensing that the tide of discoveries in electromagnetim indicated a decline of the mechanical view, Einstein replaced Newton's three absolutes -- space, time and mass, with a single one, the velocity of light. The magnitude of the velocity of light was first determined and proven to be finite independently by Ole Romer and Bradley in the eighteenth century. In the nineteenth century, Fizeau carried out the first successful measurement of the speed of light using an earthbound apparatus. Thereafter, many earthbound experiments were conducted for its determination till 1983, when its magnitude was frozen at a fixed value after it was determined up to an accuracy level of a fraction of a meter per second. Einstein considered the speed of light derived from terrestrial experiments, to be the limiting speed of all natural phenomena. Einstein stated in connection with his general relativity theory that light rays could curve only when the velocity of propagation of light varies with position. Experiments have been conducted to prove the phenomenon of light deflection to higher and higher accuracy levels, but none so far to determine the speed of light at locations closer to the sun. To verify some essential aspects of general relativity, NASA had commendably planned many costly experiments. Hence, NASA can now be expected to expeditiously plan and execute the low cost experiment proposed here, so as to conclusively verify the effect of the solar gravitational field on the speed of light, as regards the important predictions of Einstein's theory of gravitation and of its remodeled form -- the Remodeled Relativity Theory, which retained and incorporated only experimentally proven concepts and principles.
Abhijit Biswas; Krishnan RS Mani
Laser Doppler Velocimeter particle velocity measurement system
This report gives a detailed description of the operation of the Laser Doppler Velocimeter (LDV) system maintained by DIAL at MSU. LDV is used for the measurement of flow velocities and turbulence levels in various fluid flow settings. Ills report details the operation and maintenance of the LDV system and provides a first-time user with pertinent information regarding the system`s setup for a particular application. Particular attention has been given to the use of the Doppler signal analyzer (DSA) and the burst spectrum analyzer (BSA) signal processors and data analysis.
Wilson, W.W.; Srikantaiah, D.V.; Philip, T.; George, A.
The Accuracy of Vertical Air Velocities from Doppler Radar Data
Eight methods of calculating vertical air velocity in a column are compared. Each method requires some or all of the following data: horizontal divergence, vertical precipitation velocity, hydrometeor terminal fall speed, and vertical air ...
Thomas Matejka; Diana L. Bartels
Terminal Velocity Adjustments for Plate-like Crystals and Graupel
Velocity adjustments are evaluated for altitude changes using Reynolds number-Davies number correlations of the form Re = aXb which have been obtained from empirical fall velocities of ice particles. In general, the altitude adjustment was found ...
Kenneth V. Beard; Andrew J. Heymsfield
Diagnosing Mesoscale Vertical Motion from Horizontal Velocity and Density Data
The mesoscale vertical velocity is obtained by solving a generalized omega equation (? equation) using density and horizontal velocity data from three consecutive quasi-synoptic high-resolution surveys in the Alboran Sea. The Atlantic Jet (AJ) ...
Enric Pallýs Sanz; ¡lvaro Vi˙dez
Radar Wind Profiler Radial Velocity: A Comparison with Doppler Lidar
The accuracy of the radial wind velocity measured with a radar wind profiler will depend on turbulent variability and instrumental noise. Radial velocity estimates of a boundary layer wind profiler are compared with those estimated by a Doppler ...
Stephen A. Cohn; R. Kent Goodrich
Perturbations in high-velocity gas flow
High velocity explosive products or other low-density gases are often used to accelerate metal plates to high velocities. Perturbations in otherwise uniform flow configurations are sometimes sufficient to cause interactions that can rapidly destroy the integrity of the plates. In this study perturbations were introduced in uniform gas flows of detonated HE products and strongly shocked polyethylene, CH{sub 2}. The primary diagnostics were smear-camera records obtained when these gases impinged on layers of plexiglas separated by small argon-filled gaps. These records show shock-arrival times at various levels and thus determine not only the size of the perturbation but also its strength. Perturbations in HE gases running into H{sub 2} and in CH{sub 2} into H{sub 2} have been studied. Two-dimensional hydrodynamic calculations are in excellent agreement with the experiments, and enable one to study details of the flow not possible from experimental results. 1 ref., 5 figs.
Harvey, W.B.; McQueen, R.G. (Los Alamos National Lab., NM (USA))
We report spectroscopic observations of five faint (V {approx} 20) RR Lyrae stars associated with the Pisces overdensity conducted with the Gemini South Telescope. At a heliocentric and galactocentric distance of {approx}80 kpc, this is the most distant substructure in the Galactic halo known to date. We combined our observations with literature data and confirmed that the substructure is composed of two different kinematic groups. The main group contains eight stars and has (V{sub gsr}) = 50 km s{sup -1}, while the second group contains four stars at a velocity of (V{sub gsr}) = -52 km s{sup -1}, where V{sub gsr} is the radial velocity in the galactocentric standard of rest. The metallicity distribution of RR Lyrae stars in the Pisces overdensity is centered on [Fe/H] = -1.5 dex and has a width of 0.3 dex. The new data allowed us to establish that both groups are spatially extended making it very unlikely that they are bound systems, and are more likely to be debris of a tidally disrupted galaxy or galaxies. Due to small sky coverage, it is still unclear whether these groups have the same or different progenitors.
Sesar, Branimir; Ivezic, Zeljko [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195-1580 (United States); Vivas, A. Katherina [Centro de Investigaciones de Astronomia (CIDA), Apartado Postal 264, Merida 5101-A (Venezuela, Bolivarian Republic of); Duffau, Sonia, E-mail: email@example.com, E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com [Astronomisches Rechen-Institut, Zentrum fuer Astronomie der Universitaet Heidelberg, Moenchhofstrasse 12-14, D-69120 Heidelberg (Germany)
1 LAMINAR BURNING VELOCITY OF GASOLINES WITH ADDITION OF ETHANOL P. Dirrenberger1 , P.A. Glaude*1 (2014) 162-169" DOI : 10.1016/j.fuel.2013.07.015 #12;2 LAMINAR BURNING VELOCITY OF GASOLINES, Sweden Abstract The adiabatic laminar burning velocities of a commercial gasoline and of a model fuel (n
The Case of Sharp Velocity Transitions in High Vertical Wind Shear When Measuring Doppler Velocities with Narrow Nyquist Intervals
An investigation was launched following unexpected observations of step-function transitions in Doppler velocities from scanning radars in regions of high vertical wind shear. It revealed that, if wind velocity transitions are sufficiently sharp ...
FrÈdÈric Fabry; Clotilde Augros; Aldo Bellon
Force-velocity relations for multiple-molecular-motor transport
A transition rate model of cargo transport by $N$ molecular motors is proposed. Under the assumption of steady state, the force-velocity curve of multi-motor system can be derived from the force-velocity curve of single motor. Our work shows, in the case of low load, the velocity of multi-motor system can decrease or increase with increasing motor number, which is dependent on the single motor force-velocity curve. And most commonly, the velocity decreases. This gives a possible explanation to some recent
Ziqing Wang; Ming Li
Benchmark suites for improving the RDF(S) importers and exporters of ontology development tools
Abstract. Interoperability is the ability of two or more systems to interchange information and to use the information that has been interchanged. Nowadays, interoperability between ontology development tools is low. Therefore, to assess and improve this interoperability, we propose to perform a benchmarking of the interoperability of ontology development tools using RDF(S) as the interchange language. This paper presents, on the one hand, the interoperability benchmarking that is currently in progress in Knowledge Web 1 and, on the other, the benchmark suites defined and used in this benchmarking. 1
Suite of Activity-Based Probes for Cellulose-Degrading Enzymes
Microbial glycoside hydrolases play a dominant role in the biochemical conversion of cellulosic biomass to high-value biofuels. Anaerobic cellulolytic bacteria are capable of producing multicomplex catalytic subunits containing cell-adherent cellulases, hemicellulases, xylanases, and other glycoside hydrolases to facilitate the degradation of highly recalcitrant cellulose and other related plant cell wall polysaccharides. Clostridium thermocellum is a cellulosome producing bacterium that couples rapid reproduction rates to highly efficient degradation of crystalline cellulose. Herein, we have developed and applied a suite of difluoromethylphenyl aglycone, N-halogenated glycosylamine, and 2-deoxy-2-fluoroglycoside activity-based protein profiling (ABPP) probes to the direct labeling of the C. thermocellum cellulosomal secretome. These activity-based probes (ABPs) were synthesized with alkynes to harness the utility and multimodal possibilities of click chemistry, and to increase enzyme active site inclusion for LC-MS analysis. We directly analyzed ABP-labeled and unlabeled global MS data, revealing ABP selectivity for glycoside hydrolase (GH) enzymes in addition to a large collection of integral cellulosome-containing proteins. By identifying reactivity and selectivity profiles for each ABP, we demonstrate our ability to widely profile the functional cellulose degrading machinery of the bacterium. Derivatization of the ABPs, including reactive groups, acetylation of the glycoside binding groups, and mono- and disaccharide binding groups, resulted in considerable variability in protein labeling. Our probe suite is applicable to aerobic and anaerobic cellulose degrading systems, and facilitates a greater understanding of the organismal role associated within biofuel development.
Chauvigne-Hines, Lacie M.; Anderson, Lindsey N.; Weaver, Holly M.; Brown, Joseph N.; Koech, Phillip K.; Nicora, Carrie D.; Hofstad, Beth A.; Smith, Richard D.; Wilkins, Michael J.; Callister, Stephen J.; Wright, Aaron T.
A Hypothetical Burning-Velocity Formula for Very Lean Hydrogen-Air Mixtures
K. Fig. 2 Comparisons of burning-velocity predictions withcurve), when an experimental burning velocity (points) of 53and calculated laminar burning velocities of lean hydrogen-
Grcar, Joseph F
Standardization of the cumulative absolute velocity
EPRI NP-5930, A Criterion for Determining Exceedance of the Operating Basis Earthquake,'' was published in July 1988. As defined in that report, the Operating Basis Earthquake (OBE) is exceeded when both a response spectrum parameter and a second damage parameter, referred to as the Cumulative Absolute Velocity (CAV), are exceeded. In the review process of the above report, it was noted that the calculation of CAV could be confounded by time history records of long duration containing low (nondamaging) acceleration. Therefore, it is necessary to standardize the method of calculating CAV to account for record length. This standardized methodology allows consistent comparisons between future CAV calculations and the adjusted CAV threshold value based upon applying the standardized methodology to the data set presented in EPRI NP-5930. The recommended method to standardize the CAV calculation is to window its calculation on a second-by-second basis for a given time history. If the absolute acceleration exceeds 0.025g at any time during each one second interval, the earthquake records used in EPRI NP-5930 have been reanalyzed and the adjusted threshold of damage for CAV was found to be 0.16g-set.
O'Hara, T.F.; Jacobson, J.P. (Yankee Atomic Electric Co., Bolton, MA (United States))
Out-of-plane ultrasonic velocity measurement
A method for improving the accuracy of measuring the velocity and time of flight of ultrasonic signals through moving web-like materials such as paper, paperboard and the like, includes a pair of ultrasonic transducers disposed on opposing sides of a moving web-like material. In order to provide acoustical coupling between the transducers and the web-like material, the transducers are disposed in fluid-filled wheels. Errors due to variances in the wheel thicknesses about their circumference which can affect time of flight measurements and ultimately the mechanical property being tested are compensated by averaging the ultrasonic signals for a predetermined number of revolutions. The invention further includes a method for compensating for errors resulting from the digitization of the ultrasonic signals. More particularly, the invention includes a method for eliminating errors known as trigger jitter inherent with digitizing oscilloscopes used to digitize the signals for manipulation by a digital computer. In particular, rather than cross-correlate ultrasonic signals taken during different sample periods as is known in the art in order to determine the time of flight of the ultrasonic signal through the moving web, a pulse echo box is provided to enable cross-correlation of predetermined transmitted ultrasonic signals with predetermined reflected ultrasonic or echo signals during the sample period. By cross-correlating ultrasonic signals in the same sample period, the error associated with trigger jitter is eliminated.
Hall, Maclin S. (Marietta, GA); Brodeur, Pierre H. (Smyrna, GA); Jackson, Theodore G. (Atlanta, GA)
A method for improving the accuracy of measuring the velocity and time of flight of ultrasonic signals through moving web-like materials such as paper, paperboard and the like, includes a pair of ultrasonic transducers disposed on opposing sides of a moving web-like material. In order to provide acoustical coupling between the transducers and the web-like material, the transducers are disposed in fluid-filled wheels. Errors due to variances in the wheel thicknesses about their circumference which can affect time of flight measurements and ultimately the mechanical property being tested are compensated by averaging the ultrasonic signals for a predetermined number of revolutions. The invention further includes a method for compensating for errors resulting from the digitization of the ultrasonic signals. More particularly, the invention includes a method for eliminating errors known as trigger jitter inherent with digitizing oscilloscopes used to digitize the signals for manipulation by a digital computer. In particular, rather than cross-correlate ultrasonic signals taken during different sample periods as is known in the art in order to determine the time of flight of the ultrasonic signal through the moving web, a pulse echo box is provided to enable cross-correlation of predetermined transmitted ultrasonic signals with predetermined reflected ultrasonic or echo signals during the sample period. By cross-correlating ultrasonic signals in the same sample period, the error associated with trigger jitter is eliminated. 20 figs.
Hall, M.S.; Brodeur, P.H.; Jackson, T.G.
Simultaneous Measurements of Drop Size and Velocity in ...
... of entrained air velocity. An example is presented in Prahl and Wendt (1988) and Wendt and Prahl (1986) where the authors ...
Modified definition of group velocity and electromagnetic energy conservation equation
The classical definition of group velocity has two flaws: (a) the group velocity can be greater than the phase velocity in a non-dispersive medium; (b) the definition is not consistent with the principle of relativity. To remove the flaws, a modified definition is proposed. A criterion is set up to identify the justification of group velocity definition. A "superluminal power flow" is constructed to show that the electromagnetic energy conservation equation cannot uniquely define the power flow if the principle of Fermat is not taken into account.
Changbiao Wang
P wave velocity variations in the Coso region, California, derived...
P wave velocity variations in the Coso region, California, derived from local earthquake travel times Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal...
Temporal Velocity Variations beneath the Coso Geothermal Field...
events and determine the compressional and shear wave velocity as well as their ratio. In a first step, we apply traveltime tomography based on the observed microearthquake...
New Insights Into Deep Convective Core Vertical Velocities Using...
Insights Into Deep Convective Core Vertical Velocities Using ARM UHF Wind Profilers For original submission and image(s), see ARM Research Highlights http:www.arm.govscience...
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U.S. Energy Information Administration (EIA) Indexed Site
Report Period: Report Period: EIA ID NUMBER: Instructions: (e.g., Street Address, Bldg, Floor, Suite) Secure File Transfer option available at: (e.g., PO Box, RR) Electronic Transmission: The PC Electronic Data Reporting Option (PEDRO) is available. Zip Code: - If interested in software, call (202) 586-9659. Email form to: Fax form to: (202) 586-9772 - - Mail form to: Oil & Gas Survey - - U.S. Department of Energy Ben Franklin Station PO Box 279 Washington, DC 20044-0279 Questions? Call toll free: 1-800-638-8812 email@example.com Contact Name: Version No.: 2013.01 Date of this Report: Mo Day State: Year Phone No.: DOMESTIC CRUDE OIL FIRST PURCHASE REPORT Company Name: A completed form must be filed by the 30th calendar day following the end of the report
PUBLIC ACCESS: 955 LEnfant Plaza North, SW, Suite 1500, Washington, DC
th th Meeting Unconventional Resources Technology Advisory Committee July 14, 2009 1:00 p.m. EASTERN WebEx/Conference Call Meeting PUBLIC ACCESS: 955 L'Enfant Plaza North, SW, Suite 1500, Washington, DC AGENDA 12:30 Registration; Begin call in to 800-number and login to WebEx Members, Chair, Designated Federal Officer, and Committee Manager 1:00 Call to Order - Welcome Chris Hall, Committee Chair Member Roll Call and the presence of a quorum Elena Melchert Committee Manager Meeting purpose and review of the agenda; Insights regarding future funding and other pending legislation; Draft 2010 Annual Plan delivery, and pending meetings in September and October 2009 Guido DeHoratiis Designated Federal Officer 1:25 Report from the Standing Subcommittee and
An Expert Elicitation Based Study of the Proliferation Resistance of a Suite of Nuclear Power Plants
In 2008, a multi-laboratory research team completed a study evaluating the proliferation resistance (PR) characteristics of a diverse suite of four advanced nuclear reactor designs. The systems evaluated included: ï a light water reactor (a pressurized-water reactor), ï a heavy water reactor, ï a high temperature gas reactor (with a prismatic-block reactor core), ï a sodium-cooled fast reactor. The team used an expert elicitation assessment approach based on the Generation IV International Forum (GIF) Proliferation Resistance and Physical Protection (PR&PP) methodology. The team evaluated three general types of proliferation threats: 1) concealed diversion of material, 2) concealed misuse of the reactor to produce material, and 3) breakout. The evaluations took into account the intrinsic PR characteristics of each reactor and the extrinsic PR characteristics provided by generic safeguards the team considered appropriate for each reactor, based on the teamís experience and available conceptual design information.
Zentner, Michael D.; Therios, Ike; Bari, Robert A.; Cheng, Lap; Yue, Meng; Wigeland, Roald; Hassberger, Jim; Boyer, Brian; Pilat, Joseph
Developing a Comprehensive Software Suite for Advanced Reactor Performance and Safety Analysis
This paper provides an introduction to the reactor analysis capabilities of the nuclear power reactor simulation tools that are being developed as part of the U.S. Department of Energy s Nuclear Energy Advanced Modeling and Simulation (NEAMS) Toolkit. The NEAMS Toolkit is an integrated suite of multi-physics simulation tools that leverage high-performance computing to reduce uncertainty in the prediction of performance and safety of advanced reactor and fuel designs. The Toolkit effort is comprised of two major components, the Fuels Product Line (FPL), which provides tools for fuel performance analysis, and the Reactor Product Line (RPL), which provides tools for reactor performance and safety analysis. This paper provides an overview of the NEAMS RPL development effort.
Pointer, William David [ORNL; Bradley, Keith S [ORNL; Fischer, Paul F [ORNL; Smith, Micheal A [ORNL; Tautges, Timothy J [ORNL; Ferencz, Robert M [ORNL; Martineau, Richard C [ORNL; Jain, Rajeev [ORNL; Obabko, Aleksandr [Argonne National Laboratory (ANL); Billings, Jay Jay [ORNL
Ruptured Internal Iliac Artery Aneurysm: Staged Emergency Endovascular Treatment in the Interventional Radiology Suite
Ruptured aneurysms of the internal iliac artery (IIA) are rare and challenging to treat surgically. Due to their anatomic location they are difficult to operate on and perioperative morbidity is high. An endovascular approach can be helpful. We recently treated a patient with a ruptured IIA aneurysm in the interventional radiology suite with embolization of the side-branch of the IIA and placement of a covered stent in the ipsilateral common and external iliac arteries. A suitable stent-graft was not available initially and had to be brought in from elsewhere. An angioplasty balloon was temporarily placed across the ostium of the IIA to obtain hemostasis. Two hours later, the procedure was finished by placing the stent-graft.
Kelckhoven, Bas-Jeroen van [HagaZiekenhuis, Location Leyenburg, Department of Radiology (Netherlands)], E-mail: email@example.com; Bruijninckx, Boy M. A.; Knippenberg, Bob [HagaZiekenhuis, Location Leyenburg, Department of Surgery (Netherlands); Overhagen, Hans van [HagaZiekenhuis, Location Leyenburg, Department of Radiology (Netherlands)
10 10 th Meeting Ultra-Deepwater Advisory Committee July 15, 2009, 8:00 a.m. EASTERN, WebEx/Conference Call Meeting PUBLIC ACCESS: 955 L'Enfant Plaza North, SW, Suite 1500, Washington, DC AGENDA 7:30 Registration; Begin Member call in 8:00 Call to Order - Welcome Arnis Judzis, Vice-Chair Member Roll Call and the presence of a quorum Elena Melchert, Committee Manager Meeting purpose and review of the agenda; Insights regarding future funding and other pending legislation; Draft 2010 Annual Plan delivery, and pending meetings in September and October 2009 Guido DeHoratiis Designated Federal Officer 8:25 Report from the Standing Subcommittee regarding Process; Member Q/A and Discussion Mary Jane Wilson
DOE-STD-1167-2003; Respiratory Acceptance Program for Supplied-Air Suits
NOT MEASUREMENT SENSITIVE DOE-STD-1167-2003 OCTOBER 2003 DOE STANDARD THE DEPARTMENT OF ENERGY RESPIRATORY ACCEPTANCE PROGRAM FOR SUPPLIED-AIR SUITS U.S. Department of Energy AREA SAFT Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services, U.S. Department of Energy, (800) 473-4375, fax: (301) 903-9823. Available to the public from the U.S. Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161; (703) 605-6000. ii DOE-STD-1167-2003 FOREWORD This non-mandatory Technical Standard provides the Department of Energy (DOE) and contractor
Measurements of Laminar Flame Velocity for Components of Natural Gas
Measurements of Laminar Flame Velocity for Components of Natural Gas Patricia Dirrenberger1 flame velocity of components of natural gas, methane, ethane, propane, and nbutane as well as of binary and tertiary mixtures of these compounds proposed as surrogates for natural gas. These measurements have been
Multiple mapping conditioning of velocity in turbulent jet flames
Multiple mapping conditioning (MMC) has emerged as a new approach to model turbulent reacting flows. This study revises the standard MMC closure for velocity in turbulent jet flows from linearity in the reference space to linearity in the composition space. This modeling amendment ensures that the standard velocity model in conditional moment closure studies can now be used for MMC computation as well. A simplified model for the velocity-dependence of MMC drift coefficients is derived without loss of generality and is implemented for the revised velocity closure. Modeling results have been corroborated against the Direct Numerical Simulation database of a spatially evolving, planar turbulent jet flame. The revised model shows marked improvement over standard MMC closure in predicting velocity statistics close to the nozzle. (author)
Vaishnavi, P. [Mechanical Engineering Department, Imperial College, London SW7 2AZ (United Kingdom); Kronenburg, A. [Institut fuer Technische Verbrennung, Universitaet Stuttgart, 70174 Stuttgart (Germany)
An Adaptive Dealiasing Method Based on Variational Analysis for Radar Radial Velocities Scanned with Small Nyquist Velocities
Previous velocityñazimuth display (VAD)-based methods of dealiasing folded radial velocities have relied heavily on the VAD uniform-wind assumption and, thus, can fail when the uniform-wind assumption becomes poor around azimuthal circles in a ...
Qin Xu; Kang Nai
Particle Velocity and Deposition Efficiency in the Cold Spray Process
Copper powder was sprayed by the cold-gas dynamic method. In-flight particle velocities were measured with a laser-two-focus system as a function of process parameters such as gas temperature, gas pressure, and powder feed rate. Particle velocities were uniform in a relatively large volume within the plume and agreed with theoretical predictions. The presence of the substrate was found to have no significant effect on particle velocities. Cold-spray deposition efficiencies were measured on aluminum substrates as a function of particle velocity and incident angle of the plume. Deposition efficiencies of up to 95% were achieved. The critical velocity for deposition was determined to be about 640 meters per second. This work investigates both the in-flight characteristics of copper particles in a supersonic cold-spray plume and the build-up of the subsequent coating on aluminum substrates. Velocities were found to be relatively constant within a large volume of the plume. Particle counts dropped off sharply away from the central axis. The presence of a substrate was found to have no effect on the velocity of the particles. A substantial mass-loading effect on the particle velocity was observed; particle velocities begin to drop as the mass ratio of powder to gas flow rates exceeds 3%. The measured variation of velocity with gas pressure and pre-heat temperature was in fairly good agreement with theoretical predictions. Helium may be used as the driving gas instead of air in order to achieve higher particle velocities for a given temperature and pressure. Coating deposition efficiencies were found to increase with particle velocity and decrease with gun- substrate angle. There did not appear to be any dependence of the deposition efficiency on coating thickness. A critical velocity for deposition of about 640 mk appears to fit the data well. The cold-spray technique shows promise as a method for the deposition of materials which are thermally sensitive or may experience rapid oxidation under typical thermal spray conditions. High deposition efficiencies are achievable for certain coating-substrate conditions. Work remains to determine the material and microstructural properties which govern the coating process.
Dykhuizen, R.C.; Gilmore, D.L.; Neiser, R.A.; Roemer, T.J.; Smith, M.F.
Thme Date Enseignant Thme Date Enseignant AKIN Tuna Suites 16-mai AD Equa diff 24-mai RL
Page 1 Page 1 Thème Date Enseignant Thème Date Enseignant AKIN Tuna Suites 16-mai AD Equa diff 24 Probas 23-mai MAC Thème Date Enseignant Thème Date Enseignant AKIN Tuna Configurations 31-mai DT Arithm
Douai, Antoine
Predictive Services Department John B. Connally Building 301 Tarrow, Suite 304 College Station, Texas 77840-7896
. Connally Building 301 Tarrow, Suite 304 College Station, Texas 77840-7896 TEL 979/458-6530 FAX 979/458-7333 http://texasforestservice.tamu.edu Winter 2011 Wildland Fire Season Outlook for Texas September 24 days developing in the coming few weeks and months. Brad Smith, Fuels Analyst with the Texas Forest
Underground coal mining is an industry well suited for robotic automation. Human operators are severely hampered in
Abstract Underground coal mining is an industry well suited for robotic automation. Human operators approach meets the requirements for cutting straight entries and mining the proper amount of coal per cycle. Introduction The mining of soft materials, such as coal, is a large industry. Worldwide, a total of 435 million
Guestrin, Carlos
How to maximize the value of big data with the open source SpagoBI suite through a comprehensive approach
This paper describes the approach adopted by SpagoBI suite (www.spagobi.org) to manage large volumes of heterogeneous structured and unstructured data, to perform real-time Business Intelligence on Big Data streaming and to give meaning to data through ...
Monica Franceschini
Forcing and Velocity Correlations in a Vibrated Granular Monolayer
The role of forcing on the dynamics of a vertically shaken granular monolayer is investigated. Using a flat plate, surprising negative velocity correlations are measured. A mechanism for this anti-correlation is proposed with support from both experimental results and molecular dynamics simulations. Using a rough plate, velocity correlations are positive, and the velocity distribution evolves from a gaussian at very low densities to a broader distribution at high densities. These results are interpreted as a balance between stochastic forcing, interparticle collisions, and friction with the plate.
Alexis Prevost; David A. Egolf; Jeffrey S. Urbach
Superconducting spoke cavities for high-velocity applications
To date, superconducting spoke cavities have been designed, developed, and tested for particle velocities up to {beta}{sub 0}~0.6, but there is a growing interest in possible applications of multispoke cavities for high-velocity applications. We have explored the design parameter space for low-frequency, high-velocity, double-spoke superconducting cavities in order to determine how each design parameter affects the electromagnetic properties, in particular the surface electromagnetic fields and the shunt impedance. We present detailed design for cavities operating at 325 and 352 MHz and optimized for {beta}{sub 0}~=0.82 and 1.
Hopper, Christopher S. [Old Dominion U.; Delayen, Jean R. [Old Dominion U., JLAB
Property:Maximum Velocity(m/s) | Open Energy Information
Velocity(m/s) Velocity(m/s) Jump to: navigation, search Property Name Maximum Velocity(m/s) Property Type String Pages using the property "Maximum Velocity(m/s)" Showing 25 pages using this property. (previous 25) (next 25) A Alden Large Flume + 0.9 + B Bucknell Hydraulic Flume + 2.7 + C Carderock Maneuvering & Seakeeping Basin + 7.2 + Carderock Rotating Arm Tow Tank + 25.8 + Carderock Tow Tank 1 + 9.3 + Carderock Tow Tank 2 + 10.3 + Carderock Tow Tank 3 + 25.8 + Chase Tow Tank + 2.5 + D Davidson Laboratory Tow Tank + 18.3 + H Haynes Tow Tank + 1.8 + I Ice Towing Tank + 0.5 + L Lakefront Tow Tank + 2.7 + M MHL Free Surface Channel + 2 + MHL High Speed Cavitation + 25.9 + MHL Tow Tank + 6.7 + MIT Tow Tank + 1.5 + MMA Tugboat/ Barge/ Vessel + 5.1 + Maine Tow Tank + 3 +
Property:Velocity(m/s) | Open Energy Information
Velocity(m/s) Velocity(m/s) Jump to: navigation, search Property Name Velocity(m/s) Property Type String Pages using the property "Velocity(m/s)" Showing 21 pages using this property. A Alden Small Flume + >0.9 + B Bucknell Hydraulic Flume + 2.7 + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + 17 + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + 25.8 + Carderock Circulating Water Channel + 5.2 + Carderock Large Cavitation Tunnel + 18 + Carderock Subsonic Wind Tunnel + 83.8 + D DeFrees Flume 1 + 2 + DeFrees Flume 2 + 2 + DeFrees Flume 3 + 2 + DeFrees Flume 4 + 2 + M MHL Free Surface Channel + 2 + MHL High Speed Cavitation + 25.9 + MHL Student Tunnel + 4.6 + P Penn Large Water Tunnel + 16.8 + Penn Small Water Tunnel + 21 + S SAFL Channel + 6.1 +
Mass Transport Velocity in Free Barotropic PoincarÈ Waves
The mass transport velocity induced by long surface waves in a shallow, rotating viscous ocean is studied theoretically by using a Lagrangian description of motion. The depth is constant, and the water is homogeneous. Such waves are referred to ...
Frode H¯ydalsvik; Jan Erik Weber
TOPS: A Free-Fall Velocity and CTD Profiler
A free-fall instrument, TOPS, measures vertical profiles of horizontal ocean velocity, conductivity and temperature. Profiling capability extends throughout the full water column (6000 db pressure limitation). Larger vertical wavelength (water ...
S. P. Hayes; H. B. Milburn; E. F. Ford
Simulation of Three-Dimensional Turbulent Velocity Fields
New algorithms for the simulation of three-dimensional homogeneous turbulent velocity fields are compared with standard spectral domain algorithms. Results are presented for a von K·rm·n model of the covariance tensor. For typical atmospheric ...
Rod Frehlich; Larry Cornman; Robert Sharman
Composite Vertical Structure of Vertical Velocity in Nonprecipitating Cumulus Clouds
Vertical transects of Doppler vertical velocity data, obtained from an airborne profiling millimeter-wave cloud radar, are composited for a large number of cumulus clouds (Cu) at various stages of their life cycle, to examine typical circulations ...
Yonggang Wang; Bart Geerts
Efficient Dealiasing of Doppler Velocities Using Local Environment Constraints
A Doppler velocity dealiasing algorithm is described that processes one radial at a time by comparing that radial with a previous radial. This technique has worked reliably on numerous Doppler radar datasets for clear air, thunderstorm, and ...
Michael D. Eilts; Steven D. Smith
Benthic Boundary-Layer Velocity Profiles: Dependence on Averaging Period
The relationship between benthic boundary-layer velocity profiles and current meter averaging time is investigated using detailed (0.61 Hz) current measurements recorded within 1 m of the bottom on the inner continental shelf. The percentage of ...
Barry M. Lesht
GPS velocity field for the Tien Shan and surrounding regions
Measurements at ?400 campaign-style GPS points and another 14 continuously recording stations in central Asia define variations in their velocities both along and across the Kyrgyz and neighboring parts of Tien Shan. They ...
Zubovich, Alexander V.
Profiler Measurements of Vertical Velocity Fluctuations in the Ocean
A method is described for measuring the vertical component of velocity fluctuations due to three-dimensional turbulence in the ocean from a freely falling microstructure profiler. The dynamic pressure measurement relies on a commercially ...
J. N. Moum
Deep Velocity Measurements in the Western Equatorial Indian Ocean
Vertical profiles of horizontal current collected in April and June 1979 in the western Indian Ocean revealed the presence of short vertical scale (150ñ300 m) deep zonal jets, trapped to within 1∞ of the equator. Meridional velocity records ...
Rui M. Ponte; James Luyten
A New Relationship between Mean Doppler Velocity and Differential Reflectivity
A new relationship has been established linking the vertical mean Doppler velocity of raindrop spectra and the accompanying differential reflectivities. It is based upon the specific radar combination of a vertically pointing Doppler and a ...
Matthias Steiner
Dealiasing of Doppler Radar Velocities Using a Torus Mapping
A novel dealiasing algorithm for Doppler radar velocity data has been developed at the Swedish Meteorological and Hydrological Institute (SMHI). Unlike most other methods, it does not need independent wind information from other instruments (e.g.,...
G¸nther Haase; Tomas Landelius
Eulerian and Lagrangian Velocity Distributions in the North Atlantic
Velocity probability density functions (PDFs) are calculated using data from subsurface current meters in the western North Atlantic Ocean. The PDFs are weakly, but significantly, non-Gaussian. They deviate from normality because of an excess of ...
J. H. LaCasce
This report summarizes TARDEC-sponsored work at Oak Ridge National Laboratory (ORNL) during the FY11 involving low velocity ( 30 m/s or 65 mph) ball impact testing of Starphire soda lime silicate glass. The intent was to better understand low velocity impact response in the Starphire for sphere densities that bracketed that of rock. Five sphere materials were used: borosilicate glass, soda-lime silicate glass, steel, silicon nitride, and alumina. A gas gun was fabricated to produce controlled velocity delivery of the spheres against Starphire tile targets. Minimum impact velocities to initiate fracture in the Starphire were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between the any of the five sphere-Starphire-target combinations.
Morrissey, Timothy G [ORNL; Fox, Ethan E [ORNL; Wereszczak, Andrew A [ORNL; Vuono, Daniel J [ORNL
Representation of Velocity Gradient Effects in a Gaussian Puff Model
The Gaussian puff model framework is extended to provide a description of velocity shear distortion effects. An efficient splitting-merging algorithm is presented so that a maximum puff size can be specified for a calculation. This localizes the ...
R. I. Sykes; D. S. Henn
Equatorial Atlantic Velocity and Temperature Observations: FebruaryñNovember 1981
Upper ocean velocity and temperature measurements were obtained in the central equatorial Atlantic using surface moored current meters from February to November 1981. Distinct seasonal variations were observed in the zonal momentum and ...
R. H. Weisberg
Vertical Velocity Structures in an Axisymmetric, Nonhydrostatic Tropical Cyclone Model
A statistical analysis of several experiments with different microphysical parameterizations in an axisymmetric, nonhydrostatic tropical cyclone model illustrates the impact of icc-phase microphysics on model vertical velocity structure. The ...
Stephen J. Lord; Jacqueline M. Lord
Universal Velocity-Field Characteristics for a Nanowire Arbitrary Degeneracy
The effects of electric field on the carrier motion and drift velocity in nanowire (NW) are presented in this paper. When the electric field is applied in NW, the electron is expected to move in anti-parallel direction to the electric field. This is so-called randomness motion is transformed into streamlined motion in extremely high electric field. The normalized Fermi energy and relative electron population as a function of electric field are examined for various degeneracies. It was found that the electric field has lesser influence on the relative electron population with the increased degeneracy. The drift velocity in NW is shown to increase with electric field until it reaches the saturation velocity. Two approximations have been made to simplify the theoretical equation. It is also shown in this paper that when the quantum emission is taken into account, the drift and saturation velocity degrades.
Chek, Desmond C. Y.; Hashim, Abdul Manaf [Faculty of Electrical Eng., Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Tan, Michael Loong Peng [Faculty of Electrical Eng., Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Electrical Engineering Division, Engineering Department, University of Cambridge, 9 J.J. Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Arora, Vijay K. [Faculty of Electrical Eng., Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Division of Engineering and Physics, Wilkes University, Wilkes-Barre, PA 18766 (United States)
Detiding Three-Dimensional Velocity Survey Data in Coastal Waters
A three-dimensional data interpolation technique is proposed that efficiently removes tidal currents from spatial velocity surveys. The least squares method extends prior two-dimensional detiding methods to three spatial dimensions using ...
Andreas M¸nchow
The Finescale Response of Lowered ADCP Velocity Profiles
Lowered acoustic Doppler current profiler (LADCP) velocity profiles are compared with simultaneous higher-resolution expendable current profiler (XCP) profiles to determine the lowered ADCP's response at short wavelengths. Although lowered ADCP ...
Kurt Polzin; Eric Kunze; Jules Hummon; Eric Firing
Vorticity from Line-of-Sight Lidar Velocity Scans
A method is presented to compute the spanwise vorticity in polar coordinates from 2D vertical cross sections of high-resolution line-of-sight Doppler wind lidar observations. The method uses the continuity equation to derive the velocity ...
Martin Weissmann; Andreas Dˆrnbrack; James D. Doyle
Platform-Motion Correction of Velocity Measured by Doppler Lidar
The NOAA/Earth System Research Laboratory (ESRL) has two coherent Doppler lidar systems that have been deployed on board research vessels to obtain data during several experiments. The instruments measure the wind velocity relative to the motion ...
Reginald J. Hill; W. Alan Brewer; Sara C. Tucker
Seismic Velocity And Attenuation Structure Of The Geysers Geothermal Field,
Velocity And Attenuation Structure Of The Geysers Geothermal Field, Velocity And Attenuation Structure Of The Geysers Geothermal Field, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Seismic Velocity And Attenuation Structure Of The Geysers Geothermal Field, California Details Activities (1) Areas (1) Regions (0) Abstract: The Geysers geothermal field is located in northern California and is one of the world's largest producers of electricity from geothermal energy. A key resource management issue at this field is the distribution of fluid in the matrix of the reservoir rock. In this paper, we interpret seismic compressional-wave velocity and quality quotient (Q) data at The Geysers in terms of the geologic structure and fluid saturation in the reservoir. Our data consist of waveforms from approximately 300
Y-12 Site Experience with Deposition Velocity Issues
Site Experience with Site Experience with Deposition Velocity Issues Douglas Clark Analyst B&W Technical Services Y-12 May 9, 2012 Y-12 Site Experience with Deposition Velocity Issues Y-12 Specific Issues Y-12 Site Experience with Deposition Velocity Issues Windspeed - Calm Wind Conditions at Y-12 Site Y-12 Site Experience with Deposition Velocity Issues Windspeed - Stability Class Determinations * NRC RG 1.23 ΔT-only method * EPA-454/R-99-005 solar- radiation-delta-temperature (SRDT) method * Hybrid SR - DT method * wind direction standard deviation [sigma-theta (σ θ )] * elevation angle standard deviation [sigma-phi (σ φ )] * vertical wind speed standard deviation [sigma-omega (σ ω )], * wind-speed ratio method (u R ) * All evaluated using data from west
Design of regulated velocity flow assurance device for petroleum industry
The petroleum industry faces problems in transportation of crude petroleum be- cause of the deposition of paraffins, hydrates and asphaltenes on the insides of the pipeline. These are conventionally removed using either chemical inhibitors or mechani- cal devices, called pigs, which travel through the pipeline and mechanically scrape away the deposits. These pigs are propelled by the pipeline product itself and hence travel at the same velocity as the product. Research has indicated that cleaning would be better if the pigs are traveling at a relatively constant velocity of around 70% of the product velocity. This research utilizes the concept of regulating the bypass flow velocity in order to maintain the pig velocity. The bypass flow is regulated by the control unit based on the feedback from the turbine flowmeter, which monitors the bypass flow. A motorized butterfly valve is used for actually controlling the bypass flow. In addition to cleaning, the proposed pig utilizes on-board electronics like accelerom- eter and pressure transducers to store the data gathered during the pig run. This data can then be analyzed and the condition of the pipeline predicted. Thus, this research addresses the problem of designing a pig to maintain a constant velocity in order to achieve better cleaning. It also helps gather elementary data that can be used to predict the internal conditions in the pipe.
Yardi, Chaitanya Narendra
VELOCITY EVOLUTION AND THE INTRINSIC COLOR OF TYPE Ia SUPERNOVAE
To understand how best to use observations of Type Ia supernovae (SNe Ia) to obtain precise and accurate distances, we investigate the relations between spectra of SNe Ia and their intrinsic colors. Using a sample of 1630 optical spectra of 255 SNe, based primarily on data from the CfA Supernova Program, we examine how the velocity evolution and line strengths of Si II {lambda}6355 and Ca II H and K are related to the B - V color at peak brightness. We find that the maximum-light velocity of Si II {lambda}6355 and Ca II H and K and the maximum-light pseudo-equivalent width of Si II {lambda}6355 are correlated with intrinsic color, with intrinsic color having a linear relation with the Si II {lambda}6355 measurements. Ca II H and K does not have a linear relation with intrinsic color, but lower-velocity SNe tend to be intrinsically bluer. Combining the spectroscopic measurements does not improve intrinsic color inference. The intrinsic color scatter is larger for higher-velocity SNe Ia-even after removing a linear trend with velocity-indicating that lower-velocity SNe Ia are more 'standard crayons'. Employing information derived from SN Ia spectra has the potential to improve the measurements of extragalactic distances and the cosmological properties inferred from them.
Foley, Ryan J.; Sanders, Nathan E.; Kirshner, Robert P., E-mail: email@example.com [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
First Stellar Velocity Dispersion Measurement of a Luminous Quasar Host with Gemini North Laser Guide Star Adaptive Optics
We present the first use of the Gemini North laser guide star adaptive optics (LGS AO) system and an integral field unit (IFU) to measure the stellar velocity dispersion of the host of a luminous quasar. The quasar PG1426+015 (z=0.086) was observed with the Near-Infrared Integral Field Spectrometer (NIFS) on the 8m Gemini North telescope in the H-band as part of the Science Verification phase of the new ALTAIR LGS AO system. The NIFS IFU and LGS AO are well suited for host studies of luminous quasars because one can achieve a large ratio of host to quasar light. We have measured the stellar velocity dispersion of PG1426+015 from 0.1'' to 1'' (0.16 kpc to 1.6 kpc) to be 217+/-15 km/s based on high signal-to-noise ratio measurements of Si I, Mg I, and several CO bandheads. This new measurement is a factor of four more precise than a previous measurement obtained with long-slit spectroscopy and good, natural seeing, yet was obtained with a shorter net integration time. We find that PG1426+015 has a velocity dispersion that places it significantly above the M-sigma relation of quiescent galaxies and lower-luminosity active galactic nuclei with black hole masses estimated from reverberation mapping. We discuss several possible explanations for this discrepancy that could be addressed with similar observations of a larger sample of luminous quasars.
Linda C. Watson; Paul Martini; Kalliopi M. Dasyra; Misty C. Bentz; Laura Ferrarese; Bradley M. Peterson; Richard W. Pogge; Linda J. Tacconi
Precipitation Identification from Radar Wind Profiler Spectral Moment Data: Vertical Velocity Histograms, Velocity Variance, and Signal PowerñVertical Velocity Correlations
Correlations between range-corrected signal power Src and radial vertical velocity Vr, from the vertical beam of a UHF wind profiler can be used to distinguish between air- and precipitation-dominated echoes using an SrcñVr correlation diagram. ...
F. Martin Ralph; Paul J. Neiman; Dominique Ruffieux
Verification Test Suite (VERTS) For Rail Gun Applications using ALE3D: 2-D Hydrodynamics & Thermal Cases
A verification test suite has been assessed with primary focus on low reynolds number flow of liquid metals. This is representative of the interface between the armature and rail in gun applications. The computational multiphysics framework, ALE3D, is used. The main objective of the current study is to provide guidance and gain confidence in the results obtained with ALE3D. A verification test suite based on 2-D cases is proposed and includes the lid-driven cavity and the Couette flow are investigated. The hydro and thermal fields are assumed to be steady and laminar in nature. Results are compared with analytical solutions and previously published data. Mesh resolution studies are performed along with various models for the equation of state.
Najjar, F M; Solberg, J; White, D
An Improved Gaussian Jet Model for Deriving Absolute Geostrophic Velocity from Satellite Altimetry
Key aspects of a Gaussian jet model for deriving absolute geostrophic velocity from TOPEX/Poseidon altimeter data are improved. Velocities are obtained by synthesizing Gaussian fits to cross-stream velocity anomaly profiles of the Kuroshio and ...
Seung-Bum Kim; M. A. Saunders
Integration & Co-development of a Geophysical CO2 Monitoring Suite
Carbon capture and sequestration (CCS) has emerged as a key technology for dramatic short-term reduction in greenhouse gas emissions in particular from large stationary. A key challenge in this arena is the monitoring and verification (M&V) of CO2 plumes in the deep subsurface. Towards that end, we have developed a tool that can simultaneously invert multiple sub-surface data sets to constrain the location, geometry, and saturation of subsurface CO2 plumes. We have focused on a suite of unconventional geophysical approaches that measure changes in electrical properties (electrical resistance tomography, electromagnetic induction tomography) and bulk crustal deformation (til-meters). We had also used constraints of the geology as rendered in a shared earth model (ShEM) and of the injection (e.g., total injected CO{sub 2}). We describe a stochastic inversion method for mapping subsurface regions where CO{sub 2} saturation is changing. The technique combines prior information with measurements of injected CO{sub 2} volume, reservoir deformation and electrical resistivity. Bayesian inference and a Metropolis simulation algorithm form the basis for this approach. The method can (a) jointly reconstruct disparate data types such as surface or subsurface tilt, electrical resistivity, and injected CO{sub 2} volume measurements, (b) provide quantitative measures of the result uncertainty, (c) identify competing models when the available data are insufficient to definitively identify a single optimal model and (d) rank the alternative models based on how well they fit available data. We present results from general simulations of a hypothetical case derived from a real site. We also apply the technique to a field in Wyoming, where measurements collected during CO{sub 2} injection for enhanced oil recovery serve to illustrate the method's performance. The stochastic inversions provide estimates of the most probable location, shape, volume of the plume and most likely CO{sub 2} saturation. The results suggest that the method can reconstruct data with poor signal to noise ratio and use hard constraints available from many sites and applications. External interest in the approach and method is high, and already commercial and DOE entities have requested technical work using the newly developed methodology for CO{sub 2} monitoring.
Friedmann, S J
Exceptional Ground Accelerations and Velocities Caused by Earthquakes
This project aims to understand the characteristics of the free-field strong-motion records that have yielded the 100 largest peak accelerations and the 100 largest peak velocities recorded to date. The peak is defined as the maximum magnitude of the acceleration or velocity vector during the strong shaking. This compilation includes 35 records with peak acceleration greater than gravity, and 41 records with peak velocities greater than 100 cm/s. The results represent an estimated 150,000 instrument-years of strong-motion recordings. The mean horizontal acceleration or velocity, as used for the NGA ground motion models, is typically 0.76 times the magnitude of this vector peak. Accelerations in the top 100 come from earthquakes as small as magnitude 5, while velocities in the top 100 all come from earthquakes with magnitude 6 or larger. Records are dominated by crustal earthquakes with thrust, oblique-thrust, or strike-slip mechanisms. Normal faulting mechanisms in crustal earthquakes constitute under 5% of the records in the databases searched, and an even smaller percentage of the exceptional records. All NEHRP site categories have contributed exceptional records, in proportions similar to the extent that they are represented in the larger database.
Anderson, John
The Velocity of Money in a Life-Cycle Model
The determinants of the velocity of money have been examined based on life-cycle hypothesis. The velocity of money can be expressed by reciprocal of the average value of holding time which is defined as interval between participating exchanges for one unit of money. This expression indicates that the velocity is governed by behavior patterns of economic agents and open a way to constructing micro-foundation of it. It is found that time pattern of income and expense for a representative individual can be obtained from a simple version of life-cycle model, and average holding time of money resulted from the individual's optimal choice depends on the expected length of relevant planning periods.
Wang, Y; Wang, Yougui; Qiu, Hanqing
Planar velocity analysis of diesel spray shadow images
The focus of this work is to demonstrate how spatially resolved image information from diesel fuel injection events can be obtained using a forward-scatter imaging geometry, and used to calculate the velocities of liquid structures on the periphery of the spray. In order to obtain accurate velocities directly from individual diesel spray structures, those features need to be spatially resolved in the measurement. The distributed structures measured in a direct shadowgraphy arrangement cannot be reliably analyzed for this kind of velocity information. However, by utilizing an intense collimated light source and adding imaging optics which modify the signal collection, spatially resolved optical information can be retrieved from spray edge regions within a chosen object plane. This work discusses a set of measurements where a diesel spray is illuminated in rapid succession by two ultrafast laser pulses generated by a mode-locked Ti-Sapphire oscillator seeding a matched pair of regenerative amplifiers. Light fro...
Sedarsky, David
Determination of the transverse velocity of Q2237+0305
The largest systematic uncertainty present in the analysis of gravitationally microlensed quasar light curves is that of the galactic transverse velocity. We describe a method for determining the transverse velocity as well as its application to published monitoring data of Q2237+0305 (Irwin et al. 1989; Corrigan et al. 1991; Ostensen et al 1995). We find that while this data displays strong evidence for microlensing, it limits the transverse velocity to be < 500 km/sec (for microlens masses of 0.5 solar masses). In addition, by combining these results with a new method for modelling the microlensing contribution of stellar proper motions, we find that the masses of microlenses in Q2237+0305 are consistent with those of low mass stars.
J. S. B. Wyithe
The Velocity Field of Quasar Broad Emission Line Gas
In this Letter, the broad emission line (BEL) profiles of superluminal quasars with apparent jet velocities, $\\beta_{a}>10$, (ultraluminal QSOs, or ULQSOs hereafter) are studied as a diagnostic of the velocity field of the BEL emitting gas in quasars. The ULQSOs are useful because they satisfy a very strict kinematical constraint, their parsec scale jets must be propagating within $12^{\\circ}$ of the line of sight. We know the orientation of these objects with great certainty. The large BEL FWHM, $\\sim 3,000 \\mathrm{km/s} - 6,000 \\mathrm{km/s}$, in ULQSOs tend to indicate that the BEL gas has a larger component of axial velocity (either random or in a wind) along the jet direction than previously thought.
Brian Punsly
MACCS2/Deposition Velocity Workshop | Department of Energy
You are here You are here Home » MACCS2/Deposition Velocity Workshop MACCS2/Deposition Velocity Workshop The Department of Energy's Chief of Nuclear Safety hosted a MACCS2/Deposition Velocity Workshop on June 5-6, 2012, in Germantown, Maryland. Approximately 70 participants attended. The purpose of the workshop was to: Discuss MACCS2 and atmospheric dispersion models as applied to DOE consequence analysis. Discuss implementation of HSS Safety Bulletin 2011-2, Accident Analysis Parameter Update, at field sites. Develop a consistent Department-wide approach for responding to the HSS Safety Bulletin. Identify areas for improved DOE guidance for ensuring defensible consequence analyses. June Workshop Agenda- Final.docx Atmospheric Dispersion Modeling in Safety Analyses; GENII
Source shape determination with directional fragment-fragment velocity correlations
Correlation functions, constructed from directional projections of the relative velocities of fragments, are used to determine the shape of the breakup volume in coordinate space. For central collisions of 129Xe + natSn at 50 MeV per nucleon incident energy, measured with the 4pi multi-detector INDRA at GSI, a prolate shape aligned along the beam direction with an axis ratio of 1:0.7 is deduced. The sensitivity of the method is discussed in comparison with conventional fragment-fragment velocity correlations.
A. Le Fevre; C. Schwarz; G. Auger; M. L. Begemann-Blaich; N. Bellaize; R. Bittiger; F. Bocage; B. Borderie; R. Bougault; B. Bouriquet; J. L. Charvet; A. Chbihi; R. Dayras; D. Durand; J. D. Frankland; E. Galichet; D. Gourio; D. Guinet; S. Hudan; P. Lautesse; F. Lavaud; R. Legrain; O. Lopez; J. Lukasik; U. Lynen; W. F. J. Mueller; L. Nalpas; H. Orth; E. Plagnol; E. Rosato; A. Saija; C. Sfienti; B. Tamain; W. Trautmann; A. Trzcinski; K. Turzo; E. Vient; M. Vigilante; C. Volant; B. Zwieglinski
How Required Reserve Ratio Affects Distribution and Velocity of Money
In this paper the dependence of wealth distribution and the velocity of money on the required reserve ratio is examined based on a random transfer model of money and computer simulations. A fractional reserve banking system is introduced to the model where money creation can be achieved by bank loans and the monetary aggregate is determined by the monetary base and the required reserve ratio. It is shown that monetary wealth follows asymmetric Laplace distribution and latency time of money follows exponential distribution. The expression of monetary wealth distribution and that of the velocity of money in terms of the required reserve ratio are presented in a good agreement with simulation results.
Xi, N; Wang, Y; Xi, Ning; Ding, Ning; Wang, Yougui
Fermi velocity renormalization and dynamical gap generation in graphene
We study the renormalization of the Fermi velocity by the long-range Coulomb interactions between the charge carriers in the Dirac-cone approximation for the effective low-energy description of the electronic excitations in graphene at half filling. Solving the coupled system of Dyson-Schwinger equations for the dressing functions in the corresponding fermion propagator with various approximations for the particle-hole polarization we observe that Fermi velocity renormalization effects generally lead to a considerable increase of the critical coupling for dynamical gap generation and charge-density wave formation at the semimetal-insulator transition.
C. Popovici; C. S. Fischer; L. von Smekal
Clutter in the GMTI range-velocity map.
Ground Moving Target Indicator (GMTI) radar maps echo data to range and range-rate, which is a function of a moving target's velocity and its position within the antenna beam footprint. Even stationary clutter will exhibit an apparent motion spectrum and can interfere with moving vehicle detections. Consequently it is very important for a radar to understand how stationary clutter maps into radar measurements of range and velocity. This mapping depends on a wide variety of factors, including details of the radar motion, orientation, and the 3-D topography of the clutter.
Doerry, Armin Walter
We present the third data release of the RAdial Velocity Experiment (RAVE) which is the first milestone of the RAVE project, releasing the full pilot survey. The catalog contains 83,072 radial velocity measurements for 77,461 stars in the southern celestial hemisphere, as well as stellar parameters for 39,833 stars. This paper describes the content of the new release, the new processing pipeline, as well as an updated calibration for the metallicity based upon the observation of additional standard stars. Spectra will be made available in a future release. The data release can be accessed via the RAVE Web site.
Siebert, A. [Observatoire Astronomique de Strasbourg, Universite de Strasbourg, CNRS, UMR 7550, 11 rue de l'universite, 67000 Strasbourg (France); Williams, M. E. K.; Siviero, A.; Boeche, C.; Steinmetz, M.; De Jong, R. S.; Enke, H.; Anguiano, B. [Leibniz-Institut fuer Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Reid, W.; Ritter, A. [Department of Physics and Astronomy, Faculty of Sciences, Macquarie University, NSW 2109, Sydney (Australia); Fulbright, J.; Wyse, R. F. G. [Department of Physics and Astronomy, Johns Hopkins University, 366 Bloomberg Center, 3400 N. Charles St., Baltimore, MD 21218 (United States); Munari, U. [INAF Osservatorio Astronomico di Padova, 36012 Asiago (Italy); Zwitter, T. [Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana (Slovenia); Watson, F. G.; Burton, D.; Cass, C. J. P.; Fiegert, K.; Hartley, M.; Russel, K. S. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia)
Velocity of sound in the relic photon sea
We determine the velocity of sound in the blackbody gas of photons and in the gas of relic photons. Derivation is based on the thermodynamic theory of the photon gas and the Einstein relation between energy and mass. The spectral form for the n-dimensional blackbody is derived. The 1D, 2D and 3D blackbody radiation is specified. It is mentioned the possibility of creation of the Mach cone in case that the high energy cosmical particles moves with the speed greater than the velocity of sound in cosmical relic photon sea. Key words: Sound, elasticity, thermodynamics, blackbody, relic photons, Mach's cone.
Pardy, Miroslav
Miroslav Pardy
Edge Turbulence Velocity Changes with Lithium Coating on NSTX
Lithium coating improves energy confinement and eliminates edge localized modes in NSTX, but the mechanism of this improvement is not yet well understood. We used the gas-puff-imaging (GPI) diagnostic on NSTX to measure the changes in edge turbulence which occurred during a scan with variable lithium wall coating, in order to help understand the reason for the confinement improvement with lithium. There was a small increase in the edge turbulence poloidal velocity and a decrease in the poloidal velocity fluctuation level with increased lithium. The possible effect of varying edge neutral density on turbulence damping was evaluated for these cases in NSTX. __________________________________________________
A. Cao, S.J. Zweben, D.P. Stotler, M. Bell, A. Diallo, S.M. Kaye and B. LeBlanc
Velocity-Space Proton Diffusion in the Solar Wind Turbulence
We study a velocity-space quasilinear diffusion of the solar wind protons driven by oblique Alfven turbulence at proton kinetic scales. Turbulent fluctuations at these scales possess properties of kinetic Alfven waves (KAWs) that are efficient in Cherenkov resonant interactions. The proton diffusion proceeds via Cherenkov kicks and forms a quasilinear plateau - nonthermal proton tail in the velocity distribution function (VDF). The tails extend in velocity space along the mean magnetic field from 1 to (1.5-3) VA, depending on the spectral break position, turbulence amplitude at the spectral break, and spectral slope after the break. The most favorable conditions for the tail generation occur in the regions where the proton thermal and Alfven velocities are about the same, VTp/VA = 1. The estimated formation times are within 1-2 h for typical tails at 1 AU, which is much shorter than the solar wind expansion time. Our results suggest that the nonthermal proton tails, observed in-situ at all heliocentric distan...
Voitenko, Yuriy
The relativistic velocity addition law optimizes a forecast gambler's profit
We extend the projective covariant bookmaker's bets model to the forecasting gamblers case. The probability of correctness of forecasts shifts probabilities of branching. The formula for the shift of probabilities leads to the velocity addition rule of the special theory of relativity. In the absence of information about bookmaker's wagers the stochastic logarithmic rates completely determines the optimal stakes of forecast gambler.
Piotrowski, Edward W
Low inlet gas velocity high throughput biomass gasifier
The present invention discloses a novel method of operating a gasifier for production of fuel gas from carbonaceous fuels. The process disclosed enables operating in an entrained mode using inlet gas velocities of less than 7 feet per second, feedstock throughputs exceeding 4000 lbs/ft.sup.2 -hr, and pressures below 100 psia.
Feldmann, Herman F. (Worthington, OH); Paisley, Mark A. (Upper Arlington, OH)
Particle velocity measurements of the reaction zone in nitromethane
The detonation reaction-zone length in neat, deuterated, and chemically sensitized nitromethane (NM) has been measured by using several different laser-based velocity interferometry systems. The experiments involved measuring the particle velocity history at a NM/PMMA (polymethylmethacrylate) window interface during the time a detonation in the NM interacted with the interface. Initially, Fabry-Perot interferometry was used, but, because of low time resolution (>5 ns), several different configurations of VISAR interferometry were subsequently used. Early work was done with VISARs with a time resolution of about 3 ns. By making changes to the recording system, we were able to improve this to {approx}1 ns. Profiles measured at the NM/PMMA interface agree with the ZND theory, in that a spike ({approx}2.45 mm/{micro}s) is measured that is consistent with an extrapolated reactant NM Hugoniot matched to the PMMA window. The spike is rather sharp, followed by a rapid drop in particle velocity over a time of 5 to 10 ns; this is evidence of early fast reactions. Over about 50 ns, a much slower particle velocity decrease occurs to the assumed CJ condition - indicating a total reaction zone length of {approx}300 {micro}m. When the NM is chemically changed, such as replacing the hydrogen atoms with deuterium or chemically sensitizing with a base, some changes are observed in the early part of the reaction zone.
Sheffield, S. A. (Stephen A.); Engelke, R. P. (Raymond P.); Alcon, R. R. (Robert R.); Gustavsen, R. L. (Richard L.); Robbins, D. L. (David L.); Stahl, D. B. (David B.); Stacy, H. L. (Howard L.); Whitehead, M. (Michael)
Velocity and Stress in the Deep-Ocean Boundary Layer
In order to predict the response of deep ocean sediments to the near-bottom currents, accurate estimates of the near-bottom velocity and the boundary shear stress are necessary. Because of the unsteady nature of deep ocean currents, dynamic ...
S. R. McLean; J. Yean
Deep ADCP Velocity Measurements in the Gulf Stream
This paper presents observations of the velocity structure from two transects across a Gulf Stream meander near 37∞N, 68∞W. Data were collected with a vessel-mounted 75-kHz acoustic Doppler current profiler (ADCP) to a depth of about 700 m. The ...
A. V. Berezutskii; S. E. Maximov; V. E. Sklyarov; R. L. Gordon
The Cartesian Diver: A Self-Profiling Lagrangian Velocity Recorder
The Cartesian diver is an autonomous velocity profiler capable of operating to 1 km depth in the ocean. It has a self-controlled buoyancy changer which is used to control the direction of profiling. The buoyancy changer has two states, full ...
T. F. Duda; C. S. Cox; T. K. Deaton
Measurement of turbulent wind velocities using a rotating boom apparatus
The present report covers both the development of a rotating-boom facility and the evaluation of the spectral energy of the turbulence measured relative to the rotating boom. The rotating boom is composed of a helicopter blade driven through a pulley speed reducer by a variable speed motor. The boom is mounted on a semiportable tower that can be raised to provide various ratios of hub height to rotor diameter. The boom can be mounted to rotate in either the vertical or horizontal plane. Probes that measure the three components of turbulence can be mounted at any location along the radius of the boom. Special hot-film sensors measured two components of the turbulence at a point directly in front of the rotating blade. By using the probe rotated 90/sup 0/ about its axis, the third turbulent velocity component was measured. Evaluation of the spectral energy distributions for the three components of velocity indicates a large concentration of energy at the rotational frequency. At frequencies slightly below the rotational frequency, the spectral energy is greatly reduced over that measured for the nonrotating case measurements. Peaks in the energy at frequencies that are multiples of the rotation frequency were also observed. We conclude that the rotating boom apparatus is suitable and ready to be used in experiments for developing and testing sensors for rotational measurement of wind velocity from wind turbine rotors. It also can be used to accurately measure turbulent wind for testing theories of rotationally sampled wind velocity.
Sandborn, V.A.; Connell, J.R.
A fixed complexity velocity estimation method for mobile MIMO users
To estimate speed of a moving user transmitting data over a Single Input Single Output (SISO) Rayleigh fading channels, many Autocorrelation function (ACF) based schemes have been presented in literature [2-7]. Recently, it was shown that in a Multiple ... Keywords: autocorrelation function, complexity reduction, correlated MIMO channels, velocity estimation
Salman A. Khan
Velocity Autocorrelation Functions and Diffusion of Dusty Plasma
The velocity autocorrelation functions and square displacements were calculated on the basis of experimental data obtained on experimental setup with dc discharge. Computer simulation of the system of dust particles by the method of the Langevin dynamics was performed. The comparisons of experimental and theoretical results are given.
Ramazanov, T. S.; Dzhumagulova, K. N.; Daniyarov, T. T.; Dosbolayev, M. K.; Jumabekov, A. N. [IETP, al-Farabi Kazakh National University, 96a, Tole bi St., Almaty, 050012 (Kazakhstan)
Seismic imaging for velocity and attenuation structure in geothermal fields
We have applied the attenuation inversion technique developed by Evans and Zucca (1988) to a seismic tomographic data set taken at Newberry Volcano by Achauer et al. (1988). Our preliminary results suggest that the interpretation of the velocity data by Achauer et al. that a magma chamber is present 3 km beneath the caldera is not confirmed by the attenuation data.
Zucca, J.J. (Lawrence Livermore National Lab., CA (USA)); Evans, J.R. (Geological Survey, Menlo Park, CA (USA))
Effects of Velocity Shear in Advective Mixed-Layer Models
A general multidimensional model of the upper mixed layer of oceans and lakes is presented. The density profile is approximated as uniform over the depth of the layer. Such an assumption is not made for the distribution of the horizontal velocity ...
Will P. M. de Ruijter
Low Velocity Sphere Impact of a Soda Lime Silicate Glass
This report summarizes TARDEC-sponsored work at Oak Ridge National Laboratory (ORNL) during the FY11 involving low velocity (< 30 m/s or < 65 mph) ball impact testing of Starphire soda lime silicate glass. The intent was to better understand low velocity impact response in the Starphire for sphere densities that bracketed that of rock. Five sphere materials were used: borosilicate glass, soda-lime silicate glass, steel, silicon nitride, and alumina. A gas gun was fabricated to produce controlled velocity delivery of the spheres against Starphire tile targets. Minimum impact velocities to initiate fracture in the Starphire were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between the any of the five sphere-Starphire-target combinations. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) Frictional effects contribute to fracture initiation. (2) Spheres with a lower elastic modulus require less force to initiate fracture in the Starphire than spheres with a higher elastic modulus. (3) Contact-induced fracture did not initiate in the Starphire SLS for impact kinetic energies < 150 mJ. Fracture sometimes initiated or kinetic energies between {approx} 150-1100 mJ; however, it tended to occur when lower elastic modulus spheres were impacting it. Contact-induced fracture would always occur for impact energies > 1100 mJ. (4) The force necessary to initiate contact-induced fracture is higher under dynamic or impact conditions than it is under quasi-static indentation conditions. (5) Among the five used sphere materials, silicon nitride was the closest match to 'rock' in terms of both density and (probably) elastic modulus.
Wereszczak, Andrew A [ORNL; Fox, Ethan E [ORNL; Morrissey, Timothy G [ORNL; Vuono, Daniel J [ORNL
Velocity and Attenuation Structure of the Geysers Geothermal Field, California
The Geysers geothermal field is located in northern California and is one of the world's largest producers of electricity from geothermal energy. The resource consists of primarily dry steam which is produced from a low, porosity fractured graywacke. Over the last several years steam pressure at the Geysers has been dropping. Concern over decline of the resource has prompted research to understand its fundamental nature. A key issue is the distribution of fluid in the matrix of the reservoir rock. In this paper we interpret seismic compressional-wave velocity and attenuation data at the Geysers in terms of the geologic structure and fluid saturation in the reservoir. Our data consist of approximately 300 earthquakes that are of magnitude 1.2 and are distributed in depth between sea level and 2.5 km. Using compressional-wave arrival times, we invert for earthquake location, origin time, and velocity along a three-dimensional grid. Using the initial pulse width of the compressional-wave, we invert for the initial pulse width associated with the source, and the one-dimensional Q structure. We find that the velocity structure correlates with known mapped geologic units, including a velocity high that is correlated with a felsite body at depth that is known from drilling. The dry steam reservoir, which is also known from drilling, is mostly correlated with low velocity. The Q increases with depth to the top of the dry steam reservoir and decreases with depth within the reservoir. The decrease of Q with depth probably indicates that the saturation of the matrix of the reservoir rock increases with depth.
Zucca, J. J.; Hutchings, L. J.; Kasameyer, P. W.
Velocity distribution of high-energy particles and the solar neutrino problem
High energy infers high velocity and high velocity is a concept of special relativity. The Maxwellian velocity distribution is corrected to be consistent with special relativity. The corrected distribution reduces to the Maxwellian distribution for small velocities, contains a relatively depleted high-energy tail and vanishes at the velocity of light. This corrected distribution will lower solar neutrino fluxes and change solar neutrino energy spectra but keep solar sound speeds.
Jian-Miin Liu
Velocity and density spectra of the Small Magellanic Cloud
This paper reports results on the statistical analysis of HI turbulence in the Small Magellanic Cloud (SMC). We use 21 cm channel maps, obtained with the Australia Telescope Compact Array and the Parkes telescope, and analyze the spectrum of observed intensity fluctuations as a function of the velocity slice thickness. We confirm predictions by Lazarian & Pogosyan (2000) on the change of the power law index and establish the spectra of 3-D density and velocity. The obtained spectral indices, -3.3 and -3.4, are slightly more shallow than the predictions for the Kolmogorov spectrum. This contrasts to the predictions for the shock-type spectra that are steeper than the Kolmogorov one. The nature of the energy injection in the SMC is unclear as no distinct energy injection scales are observed up to the entire scale of the SMC.
S. Stanimirovi?; A. Lazarian
This report summarizes TARDEC-sponsored work at Oak Ridge National Laboratory (ORNL) during the FY11 involving low velocity (energy of impact and the elastic property mismatch between the any of the five sphere-Starphire-target combinations. The primary observations from this low velocity (energies energies between {approx} 150-1100 mJ; however, it tended to occur when lower elastic modulus spheres were impacting it. Contact-induced fracture would always occur for impact energies > 1100 mJ. (4) The force necessary to initiate contact-induced fracture is higher under dynamic or impact conditions than it is under quasi-static indentation conditions. (5) Among the five used sphere materials, silicon nitride was the closest match to 'rock' in terms of both density and (probably) elastic modulus.
The AMS-RICH velocity and charge reconstruction
The AMS detector, to be installed on the International Space Station, includes a Ring Imaging Cerenkov detector with two different radiators, silica aerogel (n=1.05) and sodium fluoride (n=1.334). This detector is designed to provide very precise measurements of velocity and electric charge in a wide range of cosmic nuclei energies and atomic numbers. The detector geometry, in particular the presence of a reflector for acceptance purposes, leads to complex Cerenkov patterns detected in a pixelized photomultiplier matrix. The results of different reconstruction methods applied to test beam data as well as to simulated samples are presented. To ensure nominal performances throughout the flight, several detector parameters have to be carefully monitored. The algorithms developed to fulfill these requirements are presented. The velocity and charge measurements provided by the RICH detector endow the AMS spectrometer with precise particle identification capabilities in a wide energy range. The expected performances on light isotope separation are discussed.
F. Barao; M. Aguilar-Benitez; L. Arruda; B. Baret; A. Barrau; G. Barreira; E. Belmont; J. Berdugo; J. Borges; M. Buenerd; D. Casadei; J. Casaus; E. Cortina; M. Costado; D. Crespo; C. Delgado; C. Diaz; L. Derome; P. Goncalves; R. Garcia-Lopez; C. de la Guia; A. Herrero; E. Lanciotti; G. Laurenti; A. Malinin; C. Mana; J. Marin; M. Mangin-Brinet; G. Martinez; A. Menchaca-Rocha; C. Palomares; R. Pereira; M. Pimenta; A. Putze; Y. Sallaz-Damaz; E. S. Seo; I. Sevilla; A. Torrento; M. Vargas-Trevino; O. Veziant
3610 N. 44th Street, Suite 250, Phoenix, AZ 85018 'óè Phone 602-808-2004 'óè
10 N. 44th Street, Suite 250, Phoenix, AZ 85018 'óè Phone 602-808-2004 'óè Fax 602-808-2099 'óè www.sunzia.net 10 N. 44th Street, Suite 250, Phoenix, AZ 85018 'óè Phone 602-808-2004 'óè Fax 602-808-2099 'óè www.sunzia.net October 17, 2013 Transmitted via electronic mail to firstname.lastname@example.com and email@example.com Subject: SunZia Southwest Transmission Project comments on Department of Energy's August 29, 2013 Federal Register Notice regarding Improving Performance of Federal Permitting and Review of Infrastructure Projects. The following comments are provided to the Department of Energy (DOE) in response to the agency's request for information on (RFI) the draft Integrated Interagency Pre-Application (IIP) Process. These comments reflect the views and suggestions of the SunZia Southwest Transmission Project (SunZia). The Bureau of Land Management is the lead agency for processing our right-of-
Superluminal group velocity through near-maximal neutrino oscillations
Recently it was suggested that the observation of superluminal neutrinos by the OPERA collaboration may be due to group velocity effects resulting from close-to-maximal oscillation between neutrino mass eigenstates, in analogy to known effects in optics. We show that superluminal propagation does occur through this effect for a series of very narrow energy ranges, but this phenomenum cannot explain the OPERA measurement.
Tim R. Morris
Fermi velocity renormalization and the excitonic insulator in graphene
We compute the Fermi velocity of the Dirac quasiparticles in clean graphene at the charge neutrality point for strong Coulomb coupling alpha_g. We perform a Lattice Monte Carlo calculation within the low-energy Dirac theory, which includes an instantaneous, long-range Coulomb interaction. This method is non-perturbative and takes full account of quantum fluctuations. We find a finite renormalized Fermi velocity v_FR > v_F, where v_F = c/300. We introduce the critical Fermi velocity renormalization v_c = v_FR(alpha_gc)/v_F, where alpha_gc is the critical coupling for the semimetal-insulator transition due to excitonic pair formation. We compare our results with empirical studies of interaction-induced spectral changes in graphene. We find v_c = 3.3, which should be contrasted with v_FR/v_F = 2 - 3 for ultra-clean suspended graphene and v_FR/v_F = 1.2 for graphene on a boron nitride substrate. Our results are consistent with the non-observation of insulating states in suspended graphene in the absence of an external magnetic field. We also discuss the dynamical critical exponent z.
JoaquÌn E. Drut; Timo A. L‰hde
Shear wave velocities from noise correlation at local scale
Cross correlations of ambient seismic noise recordings have been studied to infer shear seismic velocities with depth. Experiments have been done in the crowded and noisy historical centre of Napoli over inter-station distances from 50 m to about 400 m, whereas active seismic spreadings are prohibitive, even for just one receiver. Group velocity dispersion curves have been extracted with FTAN method from the noise cross correlations and then the non linear inversion of them has resulted in Vs profiles with depth. The information of near by stratigraphies and the range of Vs variability for samples of Neapolitan soils and rocks confirms the validity of results obtained with our expeditious procedure. Moreover, the good comparison of noise H/V frequency of the first main peak with 1D and 2D spectral amplifications encourages to continue experiments of noise cross-correlation. If confirmed in other geological settings, the proposed approach could reveal a low cost methodology to obtain reliable and detailed Vs velocity profiles.
De Nisco, G.; Nunziata, C. [Dipartimento di Scienze della Terra, Univ. Napoli Federico II (Italy); Vaccari, F. [Dipartimento di Scienze della Terra, Univ. Trieste (Italy); Panza, G. F. [Dipartimento di Scienze della Terra, Univ. Trieste (Italy); The Abdus Salam International Center for Theoretical Physics, ESP-SAND Group, Trieste (Italy)
Low Velocity Sphere Impact of a Borosilicate Glass
This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) ball impact testing of Borofloat borosilicate glass, and is a follow-up to a similar study completed by the authors on Starphire soda-lime silicate glass last year. The response of the borosilicate glass to impact testing at different angles was also studied. The Borofloat glass was supplied by the US Army Research Laboratory and its tin-side was impacted or indented. The intent was to better understand low velocity impact response in the Borofloat. Seven sphere materials were used whose densities bracket that of rock: borosilicate glass, soda-lime silicate glass, silicon nitride, aluminum oxide, zirconium oxide, carbon steel, and a chrome steel. A gas gun or a ball-drop test setup was used to produce controlled velocity delivery of the spheres against the glass tile targets. Minimum impact velocities to initiate fracture in the Borofloat were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between the seven sphere-Borofloat-target combinations. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) BS glass responded similarly to soda-lime silicate glass when spherically indented but quite differently under sphere impact conditions; (2) Frictional effects contributed to fracture initiation in BS glass when it spherically indented. This effect was also observed with soda-lime silicate glass; (3) The force necessary to initiate fracture in BS glass under spherical impact decreases with increasing elastic modulus of the sphere material. This trend is opposite to what was observed with soda-lime silicate glass. Friction cannot explain this trend and the authors do not have a legitimate explanation for it yet; (4) The force necessary to initiate contact-induced fracture is higher under dynamic conditions than under quasi-static conditions. That difference decreases with increasing elastic modulus mismatch between the sphere material and borosilicate This trend was opposite in soda-lime silicate glass; (5) Fracture in borosilicate glass occurs at lower velocities (i.e., easier) at 24{sup o} than at 0{sup o} (orthogonal) and 46{sup o} of impact for the same probability of failure. Though not analyzed yet, this suggests that a convolution of kinetic energy and friction is contributing to that trend; (6) There is a subtle indication there was intra-tile differences in spherical indentation RCIF. This likely is not a material property nor exclusive to borosilicate glass, rather, it is a statistical response of a combination of local, surface-located flaw and imposed tensile stress. Understanding of the surface flaw population and flaw positioning can likely enable prediction of spherical indentation RCIF; and (7) Contact-induced fracture did not initiate in the Borofloat BS for impact kinetic energies up to {approx} 20 mJ. For kinetic energies between {approx} 20-150 mJ, fracture sometimes initiated. Contact-induced fracture would always occur for impact energies > 150 mJ. The energy values, and their boundaries, were much lower for BS glass than they were for soda-lime silicate glass.
Morrissey, Timothy G [ORNL; Ferber, Mattison K [ORNL; Wereszczak, Andrew A [ORNL; Fox, Ethan E [ORNL
SNR Denton US LLP 1301 K Street, NW Suite 600, East Tower Washington, DC 20005-3364 USA
SNR Denton US LLP SNR Denton US LLP 1301 K Street, NW Suite 600, East Tower Washington, DC 20005-3364 USA Thomas C. Jensen Partner email@example.com D +1 202 408 3956 M 703 304 5211 T +1 202 408 6400 F +1 202 408 6399 snrdenton.com March 28, 2012 BY E-MAIL Lamont Jackson Office of Electricity Delivery and Energy Reliability Mail Code: OE-20 U.S. Department of Energy 1000 Independence Avenue SW Washington, DC 20585 Re: OE Docket No. RRTT-IR-001 Dear Mr. Jackson:: This letter is submitted on behalf of PPL Electric and Public Service Electric and Gas Company ("PSE&G") 1 ,(referred to herein as "the Companies") with respect to the Susquehanna-Roseland
Assessment of the Value, Impact, and Validity of the Jobs and Economic Development Impacts (JEDI) Suite of Models
The Jobs and Economic Development Impacts (JEDI) models, developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), use input-output methodology to estimate gross (not net) jobs and economic impacts of building and operating selected types of renewable electricity generation and fuel plants. This analysis provides the DOE with an assessment of the value, impact, and validity of the JEDI suite of models. While the models produce estimates of jobs, earnings, and economic output, this analysis focuses only on jobs estimates. This validation report includes an introduction to JEDI models, an analysis of the value and impact of the JEDI models, and an analysis of the validity of job estimates generated by JEDI model through comparison to other modeled estimates and comparison to empirical, observed jobs data as reported or estimated for a commercial project, a state, or a region.
Billman, L.; Keyser, D.
Rapid TRANSIT to the Future Using UPK for Oracleís E-Business Suite Executive Overview
This is a case study of how Denver Regional Transportation District (RTD) is utilizing Oracleís User Productivity Kit (UPK) software to maximize efficiency and effectiveness in its training programs for the implementation and rollout of Oracle E-Business Suite and Maximus maintenance management applications. This paper will answer several key questions about the use of UPK during the project, as well as why organizations should leverage UPK for their education and training rollouts as well as ongoing maintenance of those programs. Introduction and Background Denver RTD operates a public transportation system in an eight county service area with Denver, CO at the center. RTD is involved in several major transportation projects in the Denver metropolitan area including FasTracks, a 12 year regional transportation plan to improve and expand bus and rapid transit and T-REX, a combined light rail and highway expansion project. Involvement in both of these projects required RTD to
A Solbourne
Velocity shear-induced effects on electrostatic ion perturbations
Linear evolution of electrostatic perturbations in an unmagnetized electron{endash}ion plasma shear flow is studied. New physical effects, arising due to the non-normality of linear dynamics are disclosed. A new class of {ital nonperiodic collective mode} with vortical motion of ions, characterized by intense energy exchange with the mean flow, is found. It is also shown that the velocity shear induces extraction of the mean flow energy by ion-sound waves and that during the shear-induced evolution the ion-sound waves turn eventually into ion plasma oscillations. {copyright} {ital 1997 American Institute of Physics.}
Rogava, A.D. [Department of Physics, Tbilisi State University, and Department of Theoretical Astrophysics, Abastumani Astrophysical Observatory, Tbilisi, Republic of (Georgia)] [Department of Physics, Tbilisi State University, and Department of Theoretical Astrophysics, Abastumani Astrophysical Observatory, Tbilisi, Republic of (Georgia); Chagelishvili, G.D. [Department of Theoretical Astrophysics, Abastumani Astrophysical Observatory, Tbilisi, Republic of (Georgia)] [Department of Theoretical Astrophysics, Abastumani Astrophysical Observatory, Tbilisi, Republic of (Georgia); [Department of Cosmogeophysics, Space Research Institute, Moscow (Russia); Berezhiani, V.I. [Department of Plasma Physics, Institute of Physics, Tbilisi, Republic of (Georgia)] [Department of Plasma Physics, Institute of Physics, Tbilisi, Republic of (Georgia)
Determination of sputtered atom densities and velocities via simulation
Transport of sputtered atoms in a plasma sputtering unit is simulated using two known elastic collision models. The methods of studying the collision of two atoms are isotropic random scattering angle in the center of mass frame and the so-called center to center collision model in which the impact parameter is ignored and the two particles collide such as two material points. The obtained results for the density and velocity of sputtered atoms in both models are compared with some experimental reports. This investigation shows that the copper and argon atoms present pointlike behavior in the collision process.
Khorram, S.; Sobhanian, S. [Faculty of Physics, University of Tabriz, Tabriz, 51666 (Iran, Islamic Republic of); Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, 51666 (Iran, Islamic Republic of); Naghshara, H. [Faculty of Physics, University of Tabriz, Tabriz, 51666 (Iran, Islamic Republic of)
Method and apparatus for measuring flow velocity using matched filters
An apparatus and method for measuring the flow velocities of individual phase flow components of a multiphase flow is disclosed. Signals arising from flow noise disturbance are extracted from the flow, at upstream and downstream locations. The signals are processed through pairs of matched filters which are matched to the flow disturbance frequency characteristics of the phase flow component to be measured. The processed signals are then cross-correlated to determine the transit delay time of the phase flow component between sensing positions.
Raptis, A.C.
A velocity selector apparatus is described for separating and collecting an enriched fraction of the isotope of a particular element. The invention has the advantage over conventional mass spectrometers in that a magnetic field is not used, doing away with the attendant problems of magnetic field variation. The apparatus separates the isotopes by selectively accelerating the ionized constituents present in a beam of the polyisotopic substance that are of uniform kinetic energy, the acceleration being applied intermittently and at spaced points along the beam and in a direction normal to the direction of the propagation of the uniform energy beam whereby a transverse displacement of the isotopic constituents of different mass is obtained.
Britten, R.J.
Velocity Profiles in a Cylindrical Liquid Jet by Reconstructed Velocimetry
in such a way that the jet boundaries appeared sharply focused. The Newtonian liquid used in all the experiments was a mixture of 74.7% glycerol (99.9% pure) with 25.3% tri- distilled water (weight percentage). Its measured properties were: density ? = 1250... dynamics theory (or numerical simulations) for un-wetted nozzles, but to explore the effects of nozzle wetting on the velocity profiles. It is well-known that nozzle face wetting slightly enlarges the jet diameter for some distance down- stream from...
Castrejon-Pita, J.R.; Hoath, S.D.; Hutchings, I.M.
Peak ground velocity evaluation by artificial neural network for west america region
With the Peak Ground Velocity 283 records in three dimensions, the velocity attenuation relationship with distance was discussed by neural network in this paper. The earthquake magnitude, epicenter distance, site intensity and site condition were considered ...
Ben-yu Liu; Liao-yuan Ye; Mei-ling Xiao; Sheng Miao
Computation of the Streamfunction and Velocity Potential for Limited and Irregular Domains
An algorithm is proposed for the computation of streamfunction and velocity potential from given horizontal velocity vectors based on solving a minimization problem. To guarantee the uniqueness of the solution and computational reliability of the ...
Zhijin Li; Yi Chao; James C. McWilliams
An Intercomparison Study Using Electromagnetic Three-Component Turbulent Velocity Probes
An intercomparison study was performed with four Russian-made, electromagnetic probes capable of measuring three components of oceanic turbulent velocities and two single-axis velocity sensors familiar to western scientists, namely, a hot-film ...
David Y. Lai; Vadim T. Paka; Donald P. Delisi; Anatoli V. Arjannikov; Sergei A. Khanaev
A VAD-Based Dealiasing Method for Radar Velocity Data Quality Control
This paper describes a new velocityñazimuth display (VAD)-based dealiasing method developed for automated radar radial velocity data quality control to satisfy the high-quality standard and efficiency required by operational radar data ...
Qin Xu; Kang Nai; Li Wei; Pengfei Zhang; Shun Liu; David Parrish
An Optical Array Instrument for Shape and Fall Velocity Measurements of Hydrometeors
A ground-based optical array instrument for the measurement of shapes, sizes, and fall velocities of freely falling hydrometeors is presented. The instrument, the Hydrometeor Velocity and Shape Detector (HVSD), is designed to accurately measure ...
E. Barthazy; S. Gˆke; R. Schefold; D. Hˆgl
On the Structure of the Velocity Field over Progressive Mechanically-Generated Water Waves
The structure of the velocity field over a propagating wave of fixed frequency is examined. The vertical and horizontal velocities were measured in a transformed Eulerian wave-following frame of reference in a wind-wave research facility at ...
Yiannis Alex Papadimitrakis; En Yun Hsu; Robert L. Street
Robust Estimations of Current Velocities with Four-Beam Broadband ADCPs
An extended explanation of the hypothesis and equations traditionally used to transform between four-beam ADCP radial beam velocities and current velocity components is presented. This explanation includes a dissertation about the meaning of the ...
M. Gilcoto; Emlyn Jones; Luis FariÒa-Busto
Terminal Velocities of Droplets and Crystals: Power Laws with Continuous Parameters over the Size Spectrum
This paper presents a unified treatment of cloud particle fall velocities for both liquid and crystalline cloud particles over the entire size range observed in the atmosphere. The fall velocity representation is formulated in terms of the Best (...
Vitaly I. Khvorostyanov; Judith A. Curry
~, A. ~ Higashi, A. , Physics of Ice, edited by N. Riehl, B.THE VELOCITY OF DISLOCATIONS IN ICE RECEIVED LAWRENCE A. R.the velocity of dislocations in ice ref. (3,4) with which we
Forouhi, A.R.
Velocity Mapping Capabilities of Present and Future Altimeter Missions: The Role of High-Frequency Signals
A detailed analysis of the velocity field mapping capabilities from existing and future multiple altimeter missions is carried out using the Los Alamos North Atlantic high-resolution model. The velocity mapping errors on the instantaneous fields ...
P. Y. Le Traon; G. Dibarboure
Non-Gaussian Velocity Probability Density Functions: An Altimetric Perspective of the Mediterranean Sea
Velocity probability density functions (PDFs) are a key tool to study complex flows and are of great importance to model particle dispersion. The PDFs of geostrophic velocities derived from sea level anomalies maps for the Mediterranean Sea have ...
Jordi Isern-Fontanet; Emilio GarcÌa-Ladona; Jordi Font; Antonio GarcÌa-Olivares
Effects of Radar Proximity on Single-Doppler Velocity Signatures of Axisymmetric Rotation and Divergence
Geometrical and mathematical relationships are developed to explain the variation with radar range of idealized single-Doppler velocity patterns of axisymmetric rotation and divergence regions. The velocity patterns become distorted as they ...
Vincent T. Wood; Rodger A. Brown
Combining Inverted Echo Sounder and Horizontal Electric Field Recorder Measurements to Obtain Absolute Velocity Profiles
Profiles of absolute velocity are difficult to obtain in the ocean, especially over long periods of time at the same location. This paper presents a method of estimating full water column absolute horizontal velocity profiles as a function of ...
Christopher S. Meinen; Douglas S. Luther; D. Randolph Watts; Karen L. Tracey; Alan D. Chave; James Richman
A Comparison of Vertical Velocity in Cirrus Obtained from Aircraft and Lidar Divergence Measurements during FIRE
Techniques are presented to obtain vertical velocity in cirrus clouds from in situ aircraft lateral wind measurements and from ground-based remote Doppler lidar measurements. In general, direct measurements of absolute vertical velocity w from ...
I. Gultepe; A. J. Heymsfield; D. H. Lenschow
Dependence of Turbulent and Mesoscale Velocity Variances on Scale and Stability
The scale dependence of velocity variances is studied using data collected from a grassland site, a heather site, and four forested sites. The dependence of velocity variances on averaging time, used to define the fluctuation quantities, is ...
L. Mahrt; Erin Moore; Dean Vickers; N. O. Jensen
Distributions of Raindrop Sizes and Fall Velocities in a Semiarid Plateau Climate: Convective versus Stratiform Rains
Joint size and fall velocity distributions of raindrops were measured with a Particle Size and Velocity (PARSIVEL) precipitation particle disdrometer in a field experiment conducted during July and August 2007 at a semiarid continental site ...
Shengjie Niu; Xingcan Jia; Jianren Sang; Xiaoli Liu; Chunsong Lu; Yangang Liu
A new rf structure for intermediate-velocity particles
This paper describes an rf structure with high shunt impedance and good field stability for particle velocities o.1 {le} {beta} {le} 0.5. Traditionally, the drift-tube linac (DTL) has been the structure of choice for this velocity range. The new structure, called a coupled-cavity drift-tube linac (CCDTL), combines features of the Alvarez DTL and the {pi}-mode coupled-cavity linac (CCL). Each accelerating cavity is a two-cell, 0-mode DTL. The center-to-center distance between gaps is {gamma}{lambda}. Adjacent accelerating cavities have oppositely directed electric fields, alternating in phase by 180{degrees}. The chain of cavities operates in a {pi}/2 structure mode so the coupling cavities are nominally unexcited. We will discuss 2-D and 3-D electromagnetic code calculations, and some initial measurements on a low-power model of a CCDTL. We will compare shunt impedance calculations for DTL, CCL, and CCDTL structures. The CCDTL has potential application for a wide range of ion linacs. For example, high-intensity proton linacs could use the CCDTL instead of a DTL up to an energy of about 200 MeV. Another example is a stand-alone, low-duty, low-current, very high gradient, proton, cancer therapy machine. The advantage for this application would be a saving in the cost of the machine because the linac would be short.
Billen, J.H.; Krawczyk, F.L.; Wood, R.L.; Young, L.M.
This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (energy of impact and the elastic property mismatch between the seven sphere-Borofloat-target combinations. The primary observations from this low velocity (energy and friction is contributing to that trend; (6) There is a subtle indication there was intra-tile differences in spherical indentation RCIF. This likely is not a material property nor exclusive to borosilicate glass, rather, it is a statistical response of a combination of local, surface-located flaw and imposed tensile stress. Understanding of the surface flaw population and flaw positioning can likely enable prediction of spherical indentation RCIF; and (7) Contact-induced fracture did not initiate in the Borofloat BS for impact kinetic energies up to {approx} 20 mJ. For kinetic energies between {approx} 20-150 mJ, fracture sometimes initiated. Contact-induced fracture would always occur for impact energies > 150 mJ. The energy values, and their boundaries, were much lower for BS glass than they were for soda-lime silicate glass.
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
Initial Examination of Low Velocity Sphere Impact of Glass Ceramics
This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (< 30 m/s or < 65 mph) sphere impact testing of two materials from the lithium aluminosilicate family reinforced with different amounts of ceramic particulate, i.e., glass-ceramic materials, SCHOTT Resistan{trademark}-G1 and SCHOTT Resistan{trademark}-L. Both materials are provided by SCHOTT Glass (Duryea, PA). This work is a follow-up to similar sphere impact studies completed by the authors on PPG's Starphire{reg_sign} soda-lime silicate glass and SCHOTT BOROFLOAT{reg_sign} borosilicate glass. A gas gun or a sphere-drop test setup was used to produce controlled velocity delivery of silicon nitride (Si{sub 3}N{sub 4}) spheres against the glass ceramic tile targets. Minimum impact velocities to initiate fracture in the glass-ceramics were measured and interpreted in context to the kinetic energy of impact and the elastic property mismatch between sphere and target material. Quasistatic spherical indentation was also performed on both glass ceramics and their contact damage responses were compared to those of soda-lime silicate and borosilicate glasses. Lastly, variability of contact damage response was assessed by performing spherical indentation testing across the area of an entire glass ceramic tile. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) Resistan{trademark}-L glass ceramic required the highest velocity of sphere impact for damage to initiate. Starphire{reg_sign} soda-lime silicate glass was second best, then Resistan{trademark}-G1 glass ceramic, and then BOROFLOAT{reg_sign} borosilicate glass. (2) Glass-ceramic Resistan{trademark}-L also required the largest force to initiate ring crack from quasi-static indentation. That ranking was followed, in descending order, by Starphire{reg_sign} soda-lime silicate glass, Resistan{trademark}-G1 glass ceramic, and BOROFLOAT{reg_sign} borosilicate glass. (3) Spheres with a lower elastic modulus require less force to initiate fracture in Resistan{trademark}-G1 from quasi-static spherical indentation. This indicates that friction is affecting ring crack initiation in Resistan{trademark}-G1. Friction also affected ring crack initiation in Starphire{reg_sign} soda-lime silicate and BOROFLOAT{reg_sign} borosilicate glasses. Among these three materials, friction was the most pronounced (largest slope in the RCIF-elastic modulus graph) in the Starphire{reg_sign} and least pronounced in the BOROFLOAT{reg_sign}. The reason for this is not understood, but differences in deformation behavior under high contact stresses could be a cause or contributor to this. (4) The force necessary to initiate contact-induced fracture is higher under dynamic conditions than it is under quasi-static conditions in Resistan{trademark}-L and Resistan{trademark}-G1 glass ceramics. This is a trend observed too in Starphire{reg_sign} and BOROFLOAT{reg_sign}. (5) There is a subtle indication there was intra-tile differences in spherical indentation-induced ring crack initiation forces. This is not a material property nor is it exclusive to glass-ceramic Resistan{trademark}-G1 glass ceramic, rather, it is a statistical mechanical response to an accumulated history of processing and handling of that specific tile.
Morrissey, Timothy G [ORNL; Fox, Ethan E [ORNL; Wereszczak, Andrew A [ORNL; Ferber, Mattison K [ORNL
This report summarizes US Army TARDEC sponsored work at Oak Ridge National Laboratory (ORNL) involving low velocity (energy of impact and the elastic property mismatch between sphere and target material. Quasistatic spherical indentation was also performed on both glass ceramics and their contact damage responses were compared to those of soda-lime silicate and borosilicate glasses. Lastly, variability of contact damage response was assessed by performing spherical indentation testing across the area of an entire glass ceramic tile. The primary observations from this low velocity (< 30 m/s or < 65 mph) testing were: (1) Resistan{trademark}-L glass ceramic required the highest velocity of sphere impact for damage to initiate. Starphire{reg_sign} soda-lime silicate glass was second best, then Resistan{trademark}-G1 glass ceramic, and then BOROFLOAT{reg_sign} borosilicate glass. (2) Glass-ceramic Resistan{trademark}-L also required the largest force to initiate ring crack from quasi-static indentation. That ranking was followed, in descending order, by Starphire{reg_sign} soda-lime silicate glass, Resistan{trademark}-G1 glass ceramic, and BOROFLOAT{reg_sign} borosilicate glass. (3) Spheres with a lower elastic modulus require less force to initiate fracture in Resistan{trademark}-G1 from quasi-static spherical indentation. This indicates that friction is affecting ring crack initiation in Resistan{trademark}-G1. Friction also affected ring crack initiation in Starphire{reg_sign} soda-lime silicate and BOROFLOAT{reg_sign} borosilicate glasses. Among these three materials, friction was the most pronounced (largest slope in the RCIF-elastic modulus graph) in the Starphire{reg_sign} and least pronounced in the BOROFLOAT{reg_sign}. The reason for this is not understood, but differences in deformation behavior under high contact stresses could be a cause or contributor to this. (4) The force necessary to initiate contact-induced fracture is higher under dynamic conditions than it is under quasi-static conditions in Resistan{trademark}-L and Resistan{trademark}-G1 glass ceramics. This is a trend observed too in Starphire{reg_sign} and BOROFLOAT{reg_sign}. (5) There is a subtle indication there was intra-tile differences in spherical indentation-induced ring crack initiation forces. This is not a material property nor is it exclusive to glass-ceramic Resistan{trademark}-G1 glass ceramic, rather, it is a statistical mechanical response to an accumulated history of processing and handling of that specific tile.
Acoustic-velocity measurements in materials using a regenerative method
Acoustic energy is propatated through earth material between an electro-acoustic generator and a receiver which converts the received acoustic energy into electrical signals. A closed loop is formed by a variable gain amplifier system connected between the receiver and the generator. The gain of the amplifier system is increased until sustained oscillations are produced in the closed loop. The frequency of the oscillations is measured as an indication of the acoustic propagation velocity through the earth material. The amplifier gain is measured as an indication of the acoustic attenuation through the earth materials. The method is also applicable to the non-destructive testing of structural materials, such as steel, aluminum and concrete.
Laine, E.F.
Acoustic velocity measurements in materials using a regenerative method
Acoustic energy is propagated through earth material between an electro-acoustic generator and a receiver which converts the received acoustic energy into electrical signals. A closed loop is formed by a variable gain amplifier system connected between the receiver and the generator. The gain of the amplifier system is increased until sustained oscillations are produced in the closed loop. The frequency of the oscillations is measured as an indication of the acoustic propagation velocity through the earth material. The amplifier gain is measured as an indication of the acoustic attenuation through the earth materials. The method is also applicable to the non-destructive testing of structural materials, such as steel, aluminum and concrete.
Laine, Edwin F. (Alamo, CA)
This paper presents new experimental measurements of the laminar flame velocity of components of natural gas, methane, ethane, propane, and n?butane as well as of binary and tertiary mixtures of these compounds proposed as surrogates for natural gas. These measurements have been performed by the heat flux method using a newly built flat flame adiabatic burner at atmospheric pressure. The composition of the investigated air/hydrocarbon mixtures covers a wide range of equivalence ratios, from 0.6 to 2.1, for which it is possible to sufficiently stabilize the flame. Other measurements involving the enrichment of methane by hydrogen (up to 68%) and the enrichment of air by oxygen (oxycombustion techniques) were also performed. Both empirical correlations and a detailed chemical mechanism have been proposed, the predictions being satisfactorily compared with the newly obtained experimental data under a wide range of conditions.
Patricia Dirrenberger; HervÈ Le Gall; Roda Bounaceur; Olivier Herbinet; Re Glaude; Er Konnov
On anomalous diffusion in a plasma in velocity space
The problem of anomalous diffusion in momentum space is considered for plasma-like systems on the basis of a new collision integral, which is appropriate for consideration of the probability transition function (PTF) with long tails in momentum space. The generalized Fokker-Planck equation for description of diffusion (in momentum space) of particles (ions, grains etc.) in a stochastic system of light particles (electrons, or electrons and ions, respectively) is applied to the evolution of the momentum particle distribution in a plasma. In a plasma the developed approach is also applicable to the diffusion of particles with an arbitrary mass relation, due to the small characteristic momentum transfer. The cases of an exponentially decreasing in momentum space (including the Boltzmann-like) kernel in the PT-function, as well as the more general kernels, which create the anomalous diffusion in velocity space due to the long tail in the PT-function, are considered. Effective friction and diffusion coefficients f...
Trigger, S A; van Heijst, G J F; Schram, P P J M; Sokolov, I M
Detonation wave velocity and curvature of brass encased PBXN-111
Detonation velocities and wave front curvatures were measured for PBXN-111 charges encased in 5 mm thick brass tubes. In all the experiments (charge diameters from 19 to 47 mm) the brass case affected the detonation properties of PBXN-111. Steady detonation waves propagated in brass encased charges with diameters as small as 19 mm, which is about half of the unconfined failure diameter. The radii of curvature of the detonation waves at the center of the wave fronts ranged from 52 to 141 mm for charge diameters of 25 to 47 mm. The angles between the detonation wave fronts and the brass/charge interfaces were between 72 and 74 degrees. {copyright} {ital 1996 American Institute of Physics.}
Forbes, J.W.; Lemar, E.R. [Naval Surface Warfare Center, Indian Head Division, Silver Spring, Maryland 20903-5640 (United States)
Two-dimensional Imaging Velocity Interferometry: Technique and Data Analysis
We describe the data analysis procedures for an emerging interferometric technique for measuring motion across a two-dimensional image at a moment in time, i.e. a snapshot 2d-VISAR. Velocity interferometers (VISAR) measuring target motion to high precision have been an important diagnostic in shockwave physics for many years Until recently, this diagnostic has been limited to measuring motion at points or lines across a target. We introduce an emerging interferometric technique for measuring motion across a two-dimensional image, which could be called a snapshot 2d-VISAR. If a sufficiently fast movie camera technology existed, it could be placed behind a traditional VISAR optical system and record a 2d image vs time. But since that technology is not yet available, we use a CCD detector to record a single 2d image, with the pulsed nature of the illumination providing the time resolution. Consequently, since we are using pulsed illumination having a coherence length shorter than the VISAR interferometer delay ({approx}0.1 ns), we must use the white light velocimetry configuration to produce fringes with significant visibility. In this scheme, two interferometers (illuminating, detecting) having nearly identical delays are used in series, with one before the target and one after. This produces fringes with at most 50% visibility, but otherwise has the same fringe shift per target motion of a traditional VISAR. The 2d-VISAR observes a new world of information about shock behavior not readily accessible by traditional point or 1d-VISARS, simultaneously providing both a velocity map and an 'ordinary' snapshot photograph of the target. The 2d-VISAR has been used to observe nonuniformities in NIF related targets (polycrystalline diamond, Be), and in Si and Al.
Erskine, D J; Smith, R F; Bolme, C; Celliers, P; Collins, G
Material Property Estimation for Direct Detections of DNAPL using Integrated Ground-Penetrating Radar Velocity, Imaging and Attribute Analysis
The focus of our work is direct detection of DNAPLs, specifically chlorinated solvents, via material property estimation from surface ground-penetrating radar (GPR) data. We combine sophisticated GPR processing methodology with quantitative attribute analysis and material property estimation to determine the location and extent of residual and/or pooled DNAPL in both the vadose and saturated zones. An important byproduct of our research is state-of-the-art imaging which allows us to pinpoint attribute anomalies, characterize stratigraphy, identify fracture zones, and locate buried objects. Implementation and verification of these methodologies will be a significant advance in GPR research and in meeting DOE's need for reliable in-situ characterization of DNAPL contamination. Chlorinated solvents have much lower electric permittivity and conductivity than water. An electrical property contrast is induced when solvents displace water in the sediment column resulting in an anomalous GPR signature. To directly identify zones of DNAPL contamination, we focus on three aspects of reflected wave behavior--propagation velocity, frequency dependent attenuation, and amplitude variation with offset (AVO). Velocity analysis provides a direct estimate of electric permittivity, attenuation analysis provides a measure of conductivity, and AVO behavior is used to estimate the permittivity ratio at a reflecting boundary. Areas of anomalously low electric permittivity and conductivity are identified as potential DNAPL rich zones. Preliminary work illustrated significant potential for quantitative direct detection methodologies in identifying shallow DNAPL source zones. It is now necessary to verify these methodologies in a field setting. To this end, the project is field oriented and has three primary objectives: (1) Develop a suite of methodologies for direct detection of DNAPLs from surface GPR data (2) Controlled field verification at well characterized, contaminated sites (3) Exploratory contaminant detection in a field setting to be verified through direct sampling Field experiments are being conducted at the Savannah River and Hanford sites, at five DOD sites (Dover AFB, DE; McClellan AFB, CA; Port Hueneme, CA; Wurtsmith AFB, MI; Hill AFB, UT), at a former refinery site near Cincinnati, Ohio, and at a creosote wood preserving site in Fayetville, NC.
Bradford, John; Smithson, Scott B.; Holbrook, W. Stephen
4240 Carson Street, Suite 102 Denver, CO 80239 www.sre3.com SOLAR ELECTRIC SOLAR WATER HEATING ENERGY AUDITS A/C & HEATING INSULATION LIGHTING
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Colorado at Boulder, University of
Geologic Sequestration Software Suite (GS3): a collaborative approach to the management of geological GHG storage projects
Geologic storage projects associated with large anthropogenic sources of greenhouse gases (GHG) will have lifecycles that may easily span a century, involve several numerical simulation cycles, and have distinct modeling teams. The process used for numerical simulation of the fate of GHG in the subsurface follows a generally consistent sequence of steps that often are replicated by scientists and engineers around the world. Site data is gathered, assembled, interpreted, and assimilated into conceptualizations of a solid-earth model; assumptions are made about the processes to be modeled; a computational domain is specified and spatially discretized; driving forces and initial conditions are defined; the conceptual models, computational domain, and driving forces are translated into input files; simulations are executed; and results are analyzed. Then, during and after the GHG injection, a continuous monitoring of the reservoir is done and models are updated with the newly collected data. Typically the working files generated during all these steps are maintained on workstations with local backups and archived once the project has concluded along with any modeling notes and records. We are proposing a new concept for supporting the management of full-scale GHG storage projects where collaboration, flexibility, accountability and long-term access will be essential features: the Geologic Sequestration Software Suite, GS3.
Bonneville, Alain HR; Black, Gary D.; Gorton, Ian; Hui, Peter SY; Murphy, Ellyn M.; Murray, Christopher J.; Rockhold, Mark L.; Schuchardt, Karen L.; Sivaramakrishnan, Chandrika; White, Mark D.; Williams, Mark D.; Wurstner, Signe K.
Seismic analysis is of great importance in the evaluation of nuclear systems due to the heavy influence such loading has on their designs. Current Department of Energy seismic analysis techniques for a nuclear safety-related piping system typically involve application of a single conservative seismic input applied to the entire system [1]. A significant portion of this conservatism comes from the need to address the overlapping uncertainties in the seismic input and in the building response that transmits that input motion to the piping system. The approach presented in this paper addresses these two sources of uncertainty through the application of a suite of 32 input motions whose collective performance addresses the total uncertainty while each individual motion represents a single variation of it. It represents an extension of the soil-structure interaction analysis methodology of SEI/ASCE 43-05 [2] from the structure to individual piping components. Because this approach is computationally intensive, automation and other measures have been developed to make such an analysis efficient. These measures are detailed in this paper.
Anthony L. Crawford; Robert E. Spears, Ph.D.; Mark J. Russell
Hardware Workmanship Test Suite
... Section 6.4.3, General Build Quality; Part 1 Section 6.4.4, Durability; Part 1 ... complete version of the VVSG-NI in HTML, MS-Word, or PDF formats can ...
Why Test Suites
In the marketplace, testing provides a vehicle for exchanging information ... For sellers (eg, manufacturers), testing can help to substantiate claims that ...
Acoustic Imaging Suite
INLís acoustic imaging technology improves methods of capturing moving images of a specified object by using a photorefractive effect to produce a full-field image of the object without using a probe to perform a full scan of the object. INL ...
Longshore sediment transport rate calculated incorporating wave orbital velocity fluctuations
Laboratory experiments were performed to study and improve longshore sediment transport rate predictions. Measured total longshore transport in the laboratory was approximately three times greater for plunging breakers than spilling breakers. Three distinct zones of longshore transport were observed across the surf zone: the incipient breaker zone, inner surf zone, and swash zone. Transport at incipient breaking was influenced by breaker type; inner surf zone transport was dominated by wave height, independent of wave period; and swash zone transport was dependent on wave period. Selected predictive formulas to compute total load and distributed load transport were compared to laboratory and field data. Equations by Kamphuis (1991) and Madsen et al. (2003) gave consistent total sediment transport estimates for both laboratory and field data. Additionally, the CERC formula predicted measurements well if calibrated and applied to similar breaker types. Each of the distributed load models had shortcomings. The energetics model of Bodge and Dean (1987) was sensitive to fluctuations in energy dissipation and often predicted transport peaks that were not present in the data. The Watanabe (1992) equation, based on time-averaged bottom stress, predicted no transport at most laboratory locations. The Van Rijn (1993) model was comprehensive and required hydrodynamic, bedform, and sediment data. The model estimated the laboratory cross-shore distribution well, but greatly overestimated field transport. Seven models were developed in this study based on the principle that transported sediment is mobilized by the total shear stress acting on the bottom and transported by the current at that location. Shear stress, including the turbulent component, was calculated from the wave orbital velocity. Models 1 through 3 gave good estimates of the transport distribution, but underpredicted the transport peak near the plunging wave breakpoint. A suspension term was included in Models 4 through 7, which improved estimates near breaking for plunging breakers. Models 4, 5 and 7 also compared well to the field measurements. It was concluded that breaker type is an important variable in determining the amount of transport that occurs at a location. Lastly, inclusion of the turbulent component of the orbital velocity is vital in predictive sediment transport equations.
Smith, Ernest Ray
Stochastic velocity motions and processes with random time
The aim of this paper is to analyze a class of random motions which models the motion of a particle on the real line with random velocity and subject to the action of the friction. The speed randomly changes when a Poissonian event occurs. We study the characteristic and the moment generating function of the position reached by the particle at time $t>0$. We are able to derive the explicit probability distributions in few cases for which discuss the connections with the random flights. The moments are also widely analyzed. For the random motions having an explicit density law, further interesting probabilistic interpretations emerge if we deal with them varying up a random time. Essentially, we consider two different type of random times, namely Bessel and Gamma times, which contain, as particular cases, some important probability distributions (e.g. Gaussian, Exponential). In particular, for the random processes built by means of these compositions, we derive the probability distributions fixed the number of...
De Gregorio, Alessandro
Radiation Hydrodynamics Test Problems with Linear Velocity Profiles
As an extension of the works of Coggeshall and Ramsey, a class of analytic solutions to the radiation hydrodynamics equations is derived for code verification purposes. These solutions are valid under assumptions including diffusive radiation transport, a polytropic gas equation of state, constant conductivity, separable flow velocity proportional to the curvilinear radial coordinate, and divergence-free heat flux. In accordance with these assumptions, the derived solution class is mathematically invariant with respect to the presence of radiative heat conduction, and thus represents a solution to the compressible flow (Euler) equations with or without conduction terms included. With this solution class, a quantitative code verification study (using spatial convergence rates) is performed for the cell-centered, finite volume, Eulerian compressible flow code xRAGE developed at Los Alamos National Laboratory. Simulation results show near second order spatial convergence in all physical variables when using the hydrodynamics solver only, consistent with that solver's underlying order of accuracy. However, contrary to the mathematical properties of the solution class, when heat conduction algorithms are enabled the calculation does not converge to the analytic solution.
Hendon, Raymond C. [Los Alamos National Laboratory; Ramsey, Scott D. [Los Alamos National Laboratory
Generation of a suite of 3D computer-generated breast phantoms from a limited set of human subject data
Purpose: The authors previously reported on a three-dimensional computer-generated breast phantom, based on empirical human image data, including a realistic finite-element based compression model that was capable of simulating multimodality imaging data. The computerized breast phantoms are a hybrid of two phantom generation techniques, combining empirical breast CT (bCT) data with flexible computer graphics techniques. However, to date, these phantoms have been based on single human subjects. In this paper, the authors report on a new method to generate multiple phantoms, simulating additional subjects from the limited set of original dedicated breast CT data. The authors developed an image morphing technique to construct new phantoms by gradually transitioning between two human subject datasets, with the potential to generate hundreds of additional pseudoindependent phantoms from the limited bCT cases. The authors conducted a preliminary subjective assessment with a limited number of observers (n= 4) to illustrate how realistic the simulated images generated with the pseudoindependent phantoms appeared. Methods: Several mesh-based geometric transformations were developed to generate distorted breast datasets from the original human subject data. Segmented bCT data from two different human subjects were used as the 'base' and 'target' for morphing. Several combinations of transformations were applied to morph between the 'base' and 'target' datasets such as changing the breast shape, rotating the glandular data, and changing the distribution of the glandular tissue. Following the morphing, regions of skin and fat were assigned to the morphed dataset in order to appropriately assign mechanical properties during the compression simulation. The resulting morphed breast was compressed using a finite element algorithm and simulated mammograms were generated using techniques described previously. Sixty-two simulated mammograms, generated from morphing three human subject datasets, were used in a preliminary observer evaluation where four board certified breast radiologists with varying amounts of experience ranked the level of realism (from 1 ='fake' to 10 ='real') of the simulated images. Results: The morphing technique was able to successfully generate new and unique morphed datasets from the original human subject data. The radiologists evaluated the realism of simulated mammograms generated from the morphed and unmorphed human subject datasets and scored the realism with an average ranking of 5.87 {+-} 1.99, confirming that overall the phantom image datasets appeared more 'real' than 'fake.' Moreover, there was not a significant difference (p > 0.1) between the realism of the unmorphed datasets (6.0 {+-} 1.95) compared to the morphed datasets (5.86 {+-} 1.99). Three of the four observers had overall average rankings of 6.89 {+-} 0.89, 6.9 {+-} 1.24, 6.76 {+-} 1.22, whereas the fourth observer ranked them noticeably lower at 2.94 {+-} 0.7. Conclusions: This work presents a technique that can be used to generate a suite of realistic computerized breast phantoms from a limited number of human subjects. This suite of flexible breast phantoms can be used for multimodality imaging research to provide a known truth while concurrently producing realistic simulated imaging data.
Hsu, Christina M. L. [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 and Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Palmeri, Mark L. [Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Segars, W. Paul [Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Veress, Alexander I. [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Dobbins, James T. III [Carl E. Ravin Advanced Imaging Laboratories, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
Teleseismic evidence for a low-velocity body under the Coso geothermal area
Teleseismic evidence for a low-velocity body under the Coso geothermal area Teleseismic evidence for a low-velocity body under the Coso geothermal area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Teleseismic evidence for a low-velocity body under the Coso geothermal area Details Activities (1) Areas (1) Regions (0) Abstract: Teleseismic P wave arrivals were recorded by a dense array of seismograph stations located in the Coso geothermal area, California. The resulting pattern of relative residuals an area showing approximately 0.2-s excess travel time that migrates with changing source azimuth, suggesting that the area is the 'delay shadow' produced by a deep, low-velocity body. Inversion of the relative residual data for three-dimensional velocity structure determines the lateral variations in velocity to a depth of 22.5
Velocity distribution measurements in atomic beams generated using laser induced back-ablation
We present measurements of the velocity distribution of calcium atoms in an atomic beam generated using a dual-stage laser back-ablation apparatus. Distributions are measured using a velocity selective Doppler time-of-flight technique. They are Boltzmann-like with rms velocities corresponding to temperatures above the melting point for calcium. Contrary to a recent report in the literature, this method does not generate a sub-thermal atomic beam.
Denning, A; Lee, S; Ammonson, M; Bergeson, S D
One-loop fluctuation-dissipation formula for bubble-wall velocity
The limiting bubble wall velocity during a first-order electroweak phase transition is of interest in scenarios for electroweak baryogenesis. Khlebnikov has recently proposed an interesting method for computing this velocity based on the fluctuation-dissipation theorem. It is demonstrated that at one-loop order this method is identical to simple, earlier techniques for computing the wall velocity based on computing the friction from particles reflecting off or transmitting through the wall in the ideal gas limit.
Arnold, P.
This report documents the results of examining the deposition velocity of water to forests, the residence time of HTO in forests, and the relation between deposition velocity and residence time with specific consideration given to the topography and experimental work performed at SRS. A simple mechanistic model is used to obtain plausible deposition velocity and residence time values where experimental data are not available and recommendations are made for practical application in a safety analysis model.
Lee, P.; Murphy, C.; Viner, B.; Jannik, T.; Hunter, C.; Moore, M.
Recommended Tritium Oxide Deposition Velocity For Use In Savannah River Site Safety Analyses
Lee, P. L.; Murphy, C. E.; Viner, B. J.; Hunter, C. H.
On the Superficial Gas Velocity in Deep Gas-Solid Fluidized Beds
The superficial gas velocity is one of the key parameters used to determine the flow hydrodynamics in gasñsolids fluidized beds. However, the superficial velocity varies with height in practice, and there is no consistent basis for its specification. Different approaches to determine the superficial gas velocity in a deep gasñsolids system are shown to cause difficulties in developing models and in comparing predictions with experimental results. In addition, the reference conditions for superficial gas velocity are important in modeling of deep gasñsolids systems where there is a considerable pressure drop.
Li, Tingwen; Grace, John; Shadle, Lawrence; Guenther, Chris
Force criterion prediction of damage for carbon/epoxy composite panels impacted by high velocity ice
H, Kedward, K. T. Modeling Hail Ice Impacts and PredictingInvestigation of High Velocity Ice Impacts on Woven Carbon/Analysis Correlation of Hail Ice Impacting Composite
Rhymer, Jennifer D.
On the superficial gas velocity in deep gas-solids fluidized beds
In 2010, the Department of Energy (DOE) Chief of Nuclear Safety and Office of Health, Safety and Security (HSS), with the support of industry experts in atmospheric sciences and accident dose consequences analysis, performed detailed analyses of the basis for the dry deposition velocity (DV) values used in the MACCS2 computer code. As a result of these analyses, DOE concluded that the historically used default DV values of 1 centimeter/second (cm/s) for unfiltered/unmitigated releases and 0.1 cm/s for filtered/mitigated releases may not be reasonably conservative for all DOE sites and accident scenarios. HSS recently issued Safety Bulletin 2011-02, Accident Analysis Parameter Update, recommending the use of the newly developed default DV, 0.1 cm/s for an unmitigated/unfiltered release. Alternatively site specific DV values can be developed using GENII version 2 (GENII v2) computer code. Key input parameters for calculating DV values include surface roughness, maximum wind speed for calm, particle size, particle density and meteorological data (wind speed and stability class). This paper will include reasonably conservative inputs, and a truncated parametric study. In lieu of the highly-conservative recommended DV value (0.1cm/s) for unmitigated/unfiltered release, GENII v2 has been used to justify estimated 95th percentile DV values. Also presented here are atmospheric dilution factors ({chi}/Q values) calculated with the MACCS2 code using the DV values form GENII v2, {chi}/Q values calculated directly with GENII v2, and a discussion of these results compare with one another. This paper will give an overview of the process of calculating DV with GENII v2 including a discussion of the sensitivity of input parameters.
Hutchins, H.
Hohlraum Designs for High Velocity Implosions on NIF
In this paper, we compare experimental shock and capsule trajectories to design calculations using the radiation-hydrodynamics code HYDRA. The measured trajectories from surrogate ignition targets are consistent with reducing the x-ray flux on the capsule by about 85%. A new method of extracting the radiation temperature as seen by the capsule from x-ray intensity and image data shows that about half of the apparent 15% flux deficit in the data with respect to the simulations can be explained by HYDRA overestimating the x-ray flux on the capsule. The National Ignition Campaign (NIC) point-design target is designed to reach a peak fuel-layer velocity of 370 km/s by ablating 90% of its plastic (CH) ablator. The 192-beam National Ignition Facility laser drives a gold hohlraum to a radiation temperature (T{sub RAD}) of 300 eV with a 20 ns-long, 420 TW, 1.3 MJ laser pulse. The hohlraum x-rays couple to the CH ablator in order to apply the required pressure to the outside of the capsule. In this paper, we compare experimental measurements of the hohlraum T{sub RAD} and the implosion trajectory with design calculations using the code hydra. The measured radial positions of the leading shock wave and the unablated shell are consistent with simulations in which the x-ray flux on the capsule is artificially reduced by 85%. We describe a new method of inferring the T{sub RAD} seen by the capsule from time-dependent x-ray intensity data and static x-ray images. This analysis shows that hydra overestimates the x-ray flux incident on the capsule by {approx}8%.
Meezan, N B; Hicks, D G; Callahan, D A; Olson, R E; Schneider, M S; Thomas, C A; Robey, H F; Celliers, P M; Kline, J K; Dixit, S N; Michel, P A; Jones, O S; Clark, D S; Ralph, J E; Doeppner, T; MacKinnon, A J; Haan, S W; Landen, O L; Glenzer, S H; Suter, L J; Edwards, M J; Macgowan, B J; Lindl, J D; Atherton, L J
C/O HELP PLLC, 750 SEVENTEETH STREET N.W. SUITE 900 Washington, D.C. 20006 Tel. Tel. Tel. Tel. 202-378-2300
C/O HELP PLLC, 750 SEVENTEETH STREET N.W. SUITE 900 Washington, D.C. 20006 Tel. Tel. Tel. Tel. 202-378-2300 C/O HELP PLLC, 750 SEVENTEETH STREET N.W. SUITE 900 Washington, D.C. 20006 Tel. Tel. Tel. Tel. 202-378-2300 February 27, 2012 Submitted via email to: email@example.com Mr. Brian Mills Office of Electricity Delivery and Energy Reliability (OE-20) U.S. Department of Energy 1000 Independence Avenue, SW Washington, DC 20585 Re: Coordination of Federal Authorizations for Electric Transmission Facilities, RIN 1901-AB18 Dear Mr. Mills: On behalf of WIRES (www.wiresgroup.com) I am pleased to submit the attached Comments in response to the Notice of Proposed Rulemaking on Coordination of Federal Authorizations for Electric Transmission Facilities. WIRES regards the work of Assistant Secretary Hoffman and OEDER in the area of electric transmission planning
Observations of Near-Surface Oceanic Velocity Strain-Rate Variability during and after Storm Events
During August of 1977, a series of repeated profiles of the upper ocean were made at Ocean Station Papa (145∞W, 50∞N) with a velocity/temperature microstructure profiler. A strong correlation of wind-speed variations with velocity structures in ...
R. Eward Lange
Finescale Velocity-Density Characteristics and Richardson Number Statistics of the Eastern Equatorial Pacific
An analysis of finescale horizontal-velocity shear and density data collected along 110∞W longitude in the equatorial Pacific is presented. The measurements were made with the free-fall velocityñdensity profiler, TOPS. Twenty-five deployments are ...
John M. Toole; Stanley P. Hayes
POST-SHOCK TEMPERATURE AND FREE SURFACE VELOCITY MEASUREMENTS OF BASALT S. T. Stewart1 , G. B is the most common rock type on planetary surfaces. Post-shock temperature and particle velocity measurements River basalt released from a peak shock pressure of 28.9±0.2 GPa, the apparent post-shock temperature
Stewart, Sarah T.
Near-Surface Measurements of Quasi-Lagrangian Velocities in Open Water
Near-surface water velocities have been measured in the coastal zone of Lake Huron and Cape Cod Bay by tracking drifters and drogues using acoustic travel time and compass sighting techniques. The near-surface current, defined as the velocity of ...
J. H. Churchill; G. T. Csanady
Effect of temperature on wave velocities in sands and sandstones with heavy hydrocarbons
A laboratory investigation was made of the effects of temperature on wave velocities in sandstones and unconsolidated sand saturated with heavy hydrocarbons. The large decreases of the compressional and shear velocities in such sandstones and sand with increasing temperature suggest that seismic methods may be very useful in detecting heat fronts in heavy hydrocarbon reservoirs undergoing steamflooding or in-situ combustion.
Wang, Z.; Nur, A.
Results from a Velocity Transect Along the Equator from 125 to 159∞W
During MarchñApril 1980, a velocity and CTD transect was made in the Pacific along the equator from 110 to 180∞W. The horizontal baroclinic pressure gradient was observed to be primary confined between 160 and 130∞W. Direct velocity profiles ...
Ants Leetmaa; Peter F. Spain
SAE Paper 2004-01-2936 Molecular Structure Effects On Laminar Burning Velocities At
1 SAE Paper 2004-01-2936 Molecular Structure Effects On Laminar Burning Velocities At Elevated and Engineering Copyright © 2004 Society of Automotive Engineers, Inc ABSTRACT The laminar burning velocities and pressure of 304 kPa. Data have been acquired over the stoichiometry range of 0.55 1.4. The burning
Androulakis, Ioannis (Yannis)
Brief paper: Global trajectory tracking control of VTOL-UAVs without linear velocity measurements
This paper deals with the position control of Vertical Take-Off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs) without linear velocity measurements. We propose a multistage constructive procedure, exploiting the cascade property of the translational ... Keywords: Linear-velocity observer, Trajectory tracking, Unmanned Aerial Vehicles
Abdelkader Abdessameud; Abdelhamid Tayebi
Excavatability Assessment of Weathered Sedimentary Rock Mass Using Seismic Velocity Method
Seismic refraction method is one of the most popular methods in assessing surface excavation. The main objective of the seismic data acquisition is to delineate the subsurface into velocity profiles as different velocity can be correlated to identify different materials. The physical principal used for the determination of excavatability is that seismic waves travel faster through denser material as compared to less consolidated material. In general, a lower velocity indicates material that is soft and a higher velocity indicates more difficult to be excavated. However, a few researchers have noted that seismic velocity method alone does not correlate well with the excavatability of the material. In this study, a seismic velocity method was used in Nusajaya, Johor to assess the accuracy of this seismic velocity method with excavatability of the weathered sedimentary rock mass. A direct ripping run by monitoring the actual production of ripping has been employed at later stage and compared to the ripper manufacturer's recommendation. This paper presents the findings of the seismic velocity tests in weathered sedimentary area. The reliability of using this method with the actual rippability trials is also presented.
Bin Mohamad, Edy Tonnizam; Noor, Muhazian Md; Isa, Mohamed Fauzi Bin Md.; Mazlan, Ain Naadia [Department of Geotechnics and Transportation, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai. Johor (Malaysia); Saad, Rosli [Universiti Sains Malaysia, Penang (Malaysia)
Electromagnetic plane waves with negative phase velocity in charged black strings
We investigate the propagation regions of electromagnetic plane waves with negative phase velocity in the ergosphere of static charged black strings. For such a propagation, some conditions for negative phase velocity are established that depend on the metric components and the choice of the octant. We conclude that these conditions remain unaffected by the negative values of the cosmological constant.
Sharif, M., E-mail: email@example.com; Manzoor, R., E-mail: firstname.lastname@example.com [University of the Punjab, Department of Mathematics (Pakistan)
A new method of measurement of the velocities of solar neutrinos
A new method of measurement of the velocities of solar electron antineutrinos is proposed. The method is based on the assumption, that if the neutrino detector having a shape of a pipe and providing a proper angular resolution, is directed onto the optical "image" of the sun, then it would detect solar neutrinos with velocities $V_{\\widetilde{\
Elmir Dermendjiev
An Integrating VelocityñAzimuth Process Single-Doppler Radar Wind Retrieval Method
Among the single-Doppler radar wind analysis methods, the velocityñazimuth display (VAD), velocityñazimuth process (VAP), and uniform-wind (UW) methods are widely used because of their simplicity. This paper shows that the VAD, VAP, and UW ...
Xudong Liang
Modeling the Dry Deposition Velocity of Sulfur Dioxide and Sulfate in Asia
The dry deposition model was created to estimate SO2 and sulfate dry deposition velocities over nine land use types in Asia. The study domain is 20∞Sñ50∞N, 39∞ñ154∞E. Monthly averaged 1∞ ◊ 1∞ dry deposition velocities are estimated for four ...
Yiwen Xu; Gregory R. Carmichael
Reduced-dissipation remapping of velocity in staggered arbitrary Lagrangian-Eulerian methods
Remapping is an essential part of most Arbitrary Lagrangian-Eulerian (ALE) methods. In this paper, we focus on the part of the remapping algorithm that performs the interpolation of the fluid velocity field from the Lagrangian to the rezoned computational ... Keywords: Conservative interpolations, Flux-based remap, Staggered discretization, Velocity remap
David Bailey; Markus Berndt; Milan Kucharik; Mikhail Shashkov
Estimation of Critical Flow Velocity for Collapse of Gas Test Loop Booster Fuel Assembly
This paper presents calculations performed to determine the critical flow velocity for plate collapse due to static instability for the Gas Test Loop booster fuel assembly. Long, slender plates arranged in a parallel configuration can experience static divergence and collapse at sufficiently high coolant flow rates. Such collapse was exhibited by the Oak Ridge High Flux Reactor in the 1940s and the Engineering Test Reactor at the Idaho National Laboratory in the 1950s. Theoretical formulas outlined by Miller, based upon wide-beam theory and Bernoulliís equation, were used for the analysis. Calculations based upon Millerís theory show that the actual coolant flow velocity is only 6% of the predicted critical flow velocity. Since there is a considerable margin between the theoretically predicted plate collapse velocity and the design velocity, the phenomena of plate collapse due to static instability is unlikely.
Guillen; Mark J. Russell
Velocity Measurements at Three Fish Screening Facilities in the Yakima Basin, Washington : Summer 1989 Annual Report.
The Pacific Northwest Laboratory (PNL) measured the velocity conditions at three fish screening facilities in the Yakima River Basin: Wapato, Chandler, and Easton Screens. The measurement objectives were different at the three screens. At Wapato, approach and sweep velocities were measured to evaluate the effect of rearing pens in the screen forebay. A complete survey was performed at the Chandler Screens. At Easton, velocity was measured behind the screens to provide information for the installation of porosity boards to balance flow through the screens. Salmon-rearing pens used at the Wapato Canal had a minimal effect on the magnitude of approach and sweep velocities at the face of the drum screens, although the pens caused increased turbulence and variability in water velocities. The net pens did not appear to affect flows through the three fish bypasses. 8 refs., 17 figs., 5 tabs.
Abernethy, C. Scott; Neitzel, Duane A.; Lusty, E. William
Formation and evolution of interstellar filaments; Hints from velocity dispersion measurements
We investigate the gas velocity dispersions of a sample of filaments recently detected as part of the Herschel Gould Belt Survey in the IC5146, Aquila, and Polaris interstellar clouds. To measure these velocity dispersions, we use 13CO, C18O, and N2H+ line observations obtained with the IRAM 30m telescope. Correlating our velocity dispersion measurements with the filament column densities derived from Herschel data, we show that interstellar filaments can be divided into two regimes: thermally subcritical filaments, which have transonic velocity dispersions (c_s ~dispersions scaling roughly as the square root of column density (\\sigma_tot ~ \\Sigma^0.5), and are self-gravitating. The higher velocity dispersions of supercritical filaments may not directly arise from supersonic interstellar turbulence but may be driven by gravitational contraction/accretion...
Arzoumanian, Doris; Peretto, Nicolas; Konyves, Vera
P wave velocity variations in the Coso region, California, derived from
P wave velocity variations in the Coso region, California, derived from P wave velocity variations in the Coso region, California, derived from local earthquake travel times Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: P wave velocity variations in the Coso region, California, derived from local earthquake travel times Details Activities (1) Areas (1) Regions (0) Abstract: Inversion of 4036 P wave travel time residuals from 429 local earthquakes using a tomographic scheme provides information about three-dimensional upper crustal velocity variations in the Indian Wells Valley-Coso region of southeastern California. The residuals are calculated relative to a Coso-specific velocity model, corrected for station elevation, weighted, and back-projected along their ray paths through models defined with layers of blocks. Slowness variations in the surface
Field-effect transistor having a superlattice channel and high carrier velocities at high applied fields
In a field-effect transistor comprising a semiconductor having therein a source, a drain, a channel and a gate in operational relationship, there is provided an improvement wherein said semiconductor is a superlattice comprising alternating quantum well and barrier layers, the quantum well layers comprising a first direct gap semiconductor material which in bulk form has a certain bandgap and a curve of electron velocity versus applied electric field which has a maximum electron velocity at a certain electric field, the barrier layers comprising a second semiconductor material having a bandgap wider than that of said first semiconductor material, wherein the layer thicknesses of said quantum well and barrier layers are sufficiently thin that the alternating layers constitute a superlattice having a curve of electron velocity versus applied electric field which has a maximum electron velocity at a certain electric field, and wherein the thicknesses of said quantum well layers are selected to provide a superlattice curve of electron velocity versus applied electric field whereby, at applied electric fields higher than that at which the maximum electron velocity occurs in said first material when in bulk form, the electron velocities are higher in said superlattice than they are in said first semiconductor material in bulk form.
Chaffin, R.J.; Dawson, L.R.; Fritz, I.J.; Osbourn, G.C.; Zipperian, T.E.
Water Velocity Measurements on a Vertical Barrier Screen at the Bonneville Dam Second Powerhouse
Fish screens at hydroelectric dams help to protect rearing and migrating fish by preventing them from passing through the turbines and directing them towards the bypass channels by providing a sweeping flow parallel to the screen. However, fish screens may actually be harmful to fish if they become impinged on the surface of the screen or become disoriented due to poor flow conditions near the screen. Recent modifications to the vertical barrier screens (VBS) at the Bonneville Dam second powerhouse (B2) intended to increase the guidance of juvenile salmonids into the juvenile bypass system (JBS) have resulted in high mortality and descaling rates of hatchery subyearling Chinook salmon during the 2008 juvenile salmonid passage season. To investigate the potential cause of the high mortality and descaling rates, an in situ water velocity measurement study was conducted using acoustic Doppler velocimeters (ADV) in the gatewell slot at Units 12A and 14A of B2. From the measurements collected the average approach velocity, sweep velocity, and the root mean square (RMS) value of the velocity fluctuations were calculated. The approach velocities measured across the face of the VBS varied but were mostly less than 0.3 m/s. The sweep velocities also showed large variances across the face of the VBS with most measurements being less than 1.5 m/s. This study revealed that the approach velocities exceeded criteria recommended by NOAA Fisheries and Washington State Department of Fish and Wildlife intended to improve fish passage conditions.
Hughes, James S.; Deng, Zhiqun; Weiland, Mark A.; Martinez, Jayson J.; Yuan, Yong
A cylinder of heavy gas (SF{sub 6}) in air is hit by a Mach 1.2 shock. The resultant Richtmyer-Meshkov instability is observed as it propagates through the test section of the shock tube. Six images are taken after shock impact, and the velocity field at one time is measured using Particle Image Velocimetry (PIV). The images of the density field show the development of a secondary instability in the cylinder. The velocity field provides us with information about the magnitudes of the velocities as well as the magnitude of the vorticity in the flow.
Tool and a method for obtaining hydrologic flow velocity measurements in geothermal reservoirs
Downhole instruments based on a thermal perturbation principle are being developed to measure heat flow in permeable formations where convective transport of heat is important. To make heat flow measurements in these regions, the ground water velocity vector must be determined. A downhole probe has been designed to measure the local ground water velocity vector. The probe is a cylindrical heat source operated at a constant heat flux. In a convecting environment, surface temperatures on the probe are perturbed from those values of a purely conductive environment. With the aid of analytical and numerical models, these temperature differences can be related to the local velocity vector. 4 refs., 2 figs.
Carrigan, C.R.; Dunn, J.C.; Hardee, H.C.
Structure of the mean velocity and turbulence in premixed axisymmetric acetylene flames
Laser-Doppler measurements of axial mean velocities and the corresponding rms values of turbulent velocity fluctuations are reported for premixed, axisymmetric, acetylene flames together with the probability density distributions of the turbulent velocity fluctuations. All this information provides an insight into the structure of the flow field. Characteristic zones of the flow field are defined that show common features for all acetylene flames studied by the authors. These features are discussed in the paper and are suggested to characterize, in general, interesting parts of the flames.
Matovic, M.; Oka, S. (Inst. for Thermal Engineering and Energy Research, Beograd (Yugoslavia)); Durst, F. (Univ. Erlangen-Nuernberg, Erlangen (Germany). Lehrstuhl fuer Stroemungsmechanik)
Contribution from cosmological scalar perturbations to the angular velocity spectrum of extragalactic sources
The possibility of the influence of adiabatic scalar perturbations on the angular velocity spectrum of extragalactic sources is considered. The multipole expansion coefficients of the angular velocity field in terms of vector spherical harmonics are calculated. We show that there is no contribution from adiabatic perturbations to the angular spectrum for a spatially flat Universe at the dusty stage, while there is a contribution only to the electric multiple coefficients at the stage of {Lambda}-term domination. The cases of long-wavelength and short-wavelength perturbations are considered separately. The relationship between the multipole angular velocity spectrum and the primordial scalar perturbation spectrum is discussed.
Marakulin, A. O., E-mail: email@example.com; Sazhina, O. S.; Sazhin, M. V. [Moscow State University (Russian Federation)
Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine model
Wake recovery constrains the downstream spacing and density of turbines that can be deployed in turbine farms and limits the amount of energy that can be produced at a hydrokinetic energy site. This study investigates the wake recovery at the downstream of a 1:10 axial flow turbine model using a pulse-to-pulse coherent Acoustic Doppler Profiler (ADP). In addition, turbine inflow and outflow velocities were measured for calculating the thrust on the turbine. The result shows that the depth-averaged longitudinal velocity recovers to 97% of the inflow velocity at 35 turbine diameter (D) downstream of the turbine.
Gunawan, Budi [ORNL; Neary, Vincent S [ORNL; Hill, Craig [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414; Chamorro, Leonardo [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414
Laser-based diagnostics for density, temperature, velocity, and dissociation fraction in high temperature hydrogen flows
This paper is essentially a review of the current state of the art in hydrogen atom and hydrogen molecule diagnostics. This paper contains some of our own results and ideas along with results from many other laboratories. This is not intended to be an exhaustive review; instead it summarizes some techniques which we believe are ideally suited as diagnostics for high temperature hydrogen which are of paramount importance for the Space Exploration Initiative (SEI). 31 refs., 1 fig.
Sappey, A.D.; Funk, D.J.
ARM - PI Product - Cloud-Scale Vertical Velocity and Turbulent Dissipation
ProductsCloud-Scale Vertical Velocity and Turbulent ProductsCloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals Site(s) NSA General Description Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May
ARM - PI Product - SGP and TWP (Manus) Ice Cloud Vertical Velocities
ProductsSGP and TWP (Manus) Ice Cloud Vertical ProductsSGP and TWP (Manus) Ice Cloud Vertical Velocities Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : SGP and TWP (Manus) Ice Cloud Vertical Velocities 1997.01.01 - 2010.12.31 Site(s) SGP TWP General Description Daily netcdf-files of ice-cloud dynamics observed at the ARM sites at SGP (Jan1997-Dec2010) and Manus (Jul1999-Dec2010). The files include variables at different time resolution (10s, 20min, 1hr). Profiles of radar reflectivity factor (dbz), Doppler velocity (vel) as well as retrieved vertical air motion (V_air) and reflectivity-weighted particle terminal fall velocity (V_ter) are given at 10s, 20min and 1hr resolution. Lower level clouds are removed, however a multi-layer flag is included.
Surface Eddy Momentum Flux and Velocity Variances in the Southern Ocean from Geosat Altimetry
Satellite altimetry has previously been used to map the magnitude of the surface eddy variability of the global oceans, but the direction of the time-variable velocities have been more difficult to determine. Here, a technique is presented for ...
Rosemary Morrow; Richard Coleman; John Church; Dudley Chelton
A Study on the Temperature Variation of Rise Velocity for Large Clean Bubbles
A series of microphysical laboratory experiments studying the hydrodynamics of single bubbles were conducted to measure the variation of rise velocity, VB, with temperature, T, and radius, r. Bubbles with an equivalent spherical radius between ...
Ira Leifer; Ranjan K. Patro; Peter Bowyer
Chirp-Induced Bias in Velocity Measurements by a Coherent Doppler CO2 Lidar
Radial wind velocity measurements by a pulsed CO2 Doppler lidar may be biased even in stationary atmospheric conditions. The authors show it is due to random speckle fluctuations of the backscattered signal and is related to the dissymmetry of ...
Alain M. Dabas; Philippe Drobinski; Pierre H. Flamant
Horizontal Divergence and Vertical Velocity Retrievals from Doppler Radar and Wind Profiler Observations
Vertical motion profiles can be diagnosed with the mass continuity equation using horizontal divergence fields derived from various single-Doppler radar techniques such as EVAD (extended velocity-azimuth display), CEVAD (concurrent extended ...
Robert Cifelli; Steven A. Rutledge; Dennis J. Boccippio; Thomas Matejka
The Coupling of Vertical Velocity and Signal Power Observed with the SOUSY VHF Radar
The perturbations to the static stability (and hence to the radar reflectivity) and to the velocity in a vertically propagating gravity wave are correlated, and the sign of the correlation depends on whether the wave is propagating upward or ...
G. D. Nastrom; R. R¸ster; G. Schmidt
On Wind and Ocean-Velocity Correlations in a Coastal-Upwelling System
This note studies the response of a simple linear baroclinic coastal-upwelling model to fluctuating longshore winds. Correlations between wind stress and velocities are computed explicitly. It is shown that these correlations depend primarily ...
Benoit Cushman-Roisin; James J. O'Brien; Robert L. Smith
Stabilization of a wheels carrying communication satellite without angle and angular velocity sensors
An algorithm of maintaining three-axis orbital orientation using limited angular motions of the gyrostat satellite is proposed. The algorithm uses measured angular velocity of rotation of the flywheel rotors and measured angular mismatches formed on ...
V. N. Branets; V. N. Platonov; A. V. Sumarokov; S. N. Timakov
Hydraulic Interpretation of Direct Velocity Measurements in the Bab al Mandab
Acoustic Doppler Current Profiler velocity measurements in the Bab al Mandab during the period June 1995ñMarch 1996 are used to assess the hydraulic character of the exchange flow. The strait is 150 km long and contains two distinct geometrical ...
L. J. Pratt; William Johns; Stephen P. Murray; Katsurou Katsumata
Parameter estimation of permanent magnet stepper motors without position or velocity sensors
Parameter estimation of permanent magnet stepper motors without position or velocity sensors Romain identification method for permanent magnet stepper motors. Current sensors are assumed available, but position magnet stepper motors, syn- chronous motors, sensorless systems, parameter identification, elimination
Paris-Sud XI, Université de
Low-Frequency Velocity and Temperature Fluctuations in Katabatic Valley Flows
Observations of velocity and temperature fluctuations made during katabatic flow conditions in two deeply incised valleys are analyzed using variance, coherence, and phase spectra. Variance spectra obtained at valley floor sidewall locations show ...
G. L. Stone; D. E. Hoard
What Should Be Considered When Simulating Doppler Velocities Measured by Ground-Based Weather Radars?
A sophisticated and flexible simulator of Doppler velocities measured by ground-based weather radars is appended to a high-resolution nonhydrostatic atmospheric model. Sensitivity experiments are conducted by using different configurations for ...
Olivier Caumont; VÈronique Ducrocq
Impact of assimilating ocean velocity observations inferred from Lagrangian drifter data using the NCOM-4DVAR
Eulerian velocity fields are derived from 300 drifters released in the Gulf of Mexico by The Consortium for Advanced Research on Transport of Hydrocarbon in the Environment (CARTHE) during the summer 2012 Grand Lagrangian Deployment (GLAD) ...
Matthew J. Carrier; Hans Ngodock; Scott Smith; Gregg Jacobs; Philip Muscarella; Tamay Ozgokmen; Brian Haus; Bruce Lipphardt
Effects of CO/sub 2/ flooding on wave velocities in rocks with hydrocarbons
Compressional and shear-wave velocities were measured in the laboratory in seven sandstones (porosities ranging from 6 to 29%) and one unconsolidated sand (37% porosity) saturated with n-hexadecane (C/sub 16/H/sub 34/) both before and after CO/sub 2/ flooding. CO/sub 2/ flooding decreased compressional-wave velocities significantly, while shear-wave velocities were less affected. The magnitude of these effects was found to depend on confining and pore pressures, temperature, and porosities of the rocks. The experimental results and theoretical analysis show that the decreases in compressional-wave velocities caused by CO/sub 2/ flooding may be seismically resolvable in situ. Therefore, seismic--especially high-frequency, high-resolution seismic--methods may be useful in mapping and locating CO/sub 2/ zones, tracking movements of CO/sub 2/ fronts, and monitoring flooding processes in reservoirs undergoing CO/sub 2/ flooding.
Wang, Z. (Core Labs., Calgary (CA)); Nur, A.M. (Stanford Univ., Geophysics Dept., CA (US))
Prognostic Equation for Radar Radial Velocity Derived by Considering Atmospheric Refraction and Earth Curvature
The prognostic equation for the radial velocity field observed with a Doppler radar is derived to include the effects of atmospheric refraction and earth curvature on radar-beam height and slope angle. The derived equation, called the radial ...
Qin Xu; Li Wei
Effects of Radar Sampling on Single-Doppler Velocity Signatures of Mesocyclones and Tornadoes
Simulated WSR-88D (Weather Surveillance Radar-1988 Doppler) radar data were used to investigate the effects of discrete azimuthal sampling on Doppler velocity signatures of modeled mesocyclones and tornadoes at various ranges from the radar and ...
Simultaneous Velocity Ambiguity Resolution and Noise Suppression for Multifrequency Coherent Doppler Sonar
Coherent Doppler sonar is a useful tool for noninvasive measurement of ocean currents, sediment transport, and turbulence in coastal environments. Various methods have been proposed to separately address two of its inherent limitations: velocity ...
Jeremy Dillon; Len Zedel; Alex E. Hay
Momentum Flux from Wind to Aqueous Flows at Various Wind Velocities and Fetches
The fraction of wind stress consumed in driving aqueous flows has been estimated for various nondimensional fetches, derived from the wind velocity, fetch, and gravitational acceleration. The fraction is shown to vary with both fetch and wind ...
Jin Wu
Use of Mass- and Area-Dimensional Power Laws for Determining Precipitation Particle Terminal Velocities
Based on boundary layer theory and a comparison of empirical power laws relating the Reynolds and Best numbers, it was apparent that the primary variables governing a hydrometeor's terminal velocity were its mass, its area projected to the flow, ...
David L. Mitchell
Rainfall Doppler Velocity Measurements from Spaceborne Radar: Overcoming Nonuniform Beam-Filling Effects
For vertical Doppler velocity measurements of a homogeneous rain field, the standard spectral moment estimation techniques commonly used by ground-based and airborne Doppler rain radars can be readily extended for spaceborne application, provided ...
Simone Tanelli; Eastwood Im; Stephen L. Durden; Luca Facheris; Dino Giuli; Eric A. Smith
Extended Velocity Track Display (EVTD): An Improved Processing Method for Doppler Radar Observations of Tropical Cyclones
The authors present an improved version of the velocity track display (VTD) method, proposed by Lee et al., to deduce the primary vortex circulation in hurricanes from airborne Doppler radar data obtained during straightline legs through the ...
Frank Roux; Frank D. Marks Jr.
Estimation of Velocity from Argos-tracked Surface Drifters during OCEAN STORMS
Modern surface drifters tracked by Argos are an attractive method for measuring the spatial structure of near-surface currents. This note discusses the accuracy to which velocity can be estimated from such data, assuming perfect drifters. The ...
Eric A. D'Asaro
On the Correction of Temperature and Velocity Time Series for Mooring Motion
Several schemes for correcting temperature and velocity measurements from moored current meters are tested on two moorings, one of which experienced large vertical excursions as the Gulf Stream meandered over it. The addition of two extra ...
Nelson G. Hogg
An Electromagnetic Vorticity and Velocity Sensor for Observing Finescale Kinetic Fluctuations in the Ocean
An instrument has been developed that measures finescale velocity and vorticity in seawater based on the principles of motional induction. This instrument, the electromagnetic vorticity meter (EMVM), measures components of the gradient and ...
Thomas B. Sanford; James A. Carlson; John H. Dunlap; Mark D. Prater; Ren-Chieh Lien
Sources of Gravity Wave Activity Seen in the Vertical Velocities Observed by the Flatland VHF Radar
Observations of vertical velocity made with the Flatland VHF radar located in the extremely flat terrain near Champaign, Illinois, are used to study sources of enhanced variance. The variance is used as an indicator of gravity wave activity. In ...
G. D. Nastrom; M. R. Peterson; J. L. Green; K. S. Gage; T. E. VanZandt
Identifying Doppler Velocity Contamination Caused by Migrating Birds. Part II: Bayes Identification and Probability Tests
Based on the Bayesian statistical decision theory, a probabilistic quality control (QC) technique is developed to identify and flag migrating-bird-contaminated sweeps of level II velocity scans at the lowest elevation angle using the QC ...
Shun Liu; Qin Xu; Pengfei Zhang
Estimates of the Seasonal Mean Vertical Velocity Fields of the Extratropical Northern Hemisphere
Wintertime and summertime mean 500 mb vertical velocity fields for the extratropical Northern Hemisphere are calculated by several methods from general circulation statistics compiled from National Meteorological Center (NMC) operational analyses ...
Glenn H. White
R.W. Shefer, Int. J. Hydrogen Energy 28 (2003) 1131-1141. P.burning velocities of lean hydrogen-air flames at 1 atm andFORMULA FOR VERY LEAN HYDROGEN-AIR MIXTURES by Forman A.
A Correction Method for Turbulence Measurements with a 3D Acoustic Doppler Velocity Profiler
A method is proposed to reduce the noise contribution to mean turbulence parameters obtained by 3D acoustic Doppler velocity profiler measurements. It is based on a noise spectrum reconstruction from cross-spectra evaluations of two independent ...
D. Hurther; U. Lemmin
Real-Time Retrieval of the Wind from Aliased Velocities Measured by Doppler Radars
Doppler radar measurements provide the radial wind within an unambiguous interval due to the limited value of the sampling frequency (pulse repetition frequency). Many algorithms have been developed to retrieve true wind velocities from measured ...
Pierre Tabary; Georges Scialom; Urs Germann
Instrumental Uncertainties in ZñR Relationships and Raindrop Fall Velocities
This study demonstrates the sensitivity of reflectivityñrainfall rate (ZñR) relationships, which were derived from disdrometer-based drop size distribution measurements, to the fall velocity of the drops. The dataset used comes from the ...
Christian Salles; Jean-Dominique Creutin
Vertical Velocity and Microphysical Distributions Related to Rapid Intensification in a Simulation of Hurricane Dennis (2005)
A 1-km Weather Research and Forecasting model simulation of Hurricane Dennis was used to identify precursors in vertical velocity and latent heating distributions to rapid intensification (RI). Although the observed structure qualitatively ...
Greg M. McFarquhar; Brian F. Jewett; Matthew S. Gilmore; Stephen W. Nesbitt; Tsung-Lin Hsieh
The Effect of Nonlinear Drag on the Motion and Settling Velocity of Heavy Particles
The effects of nonlinear drag on the motion and settling velocity of heavy particles in a turbulent atmosphere are investigated. The authors approach the problem rather systematically by first considering the response of particles to much simpler ...
J. E. Stout; S. P. Arya; E. L. Genikhovich
Estimating the Vertical Component of Water Velocity from Measurements Collected with a Free-fall Vehicle
Estimated of the vertical component of water velocity are made with measurements of the pressure-change rate and rotation rate recorded by the free-fall vehicle ìCartesian diverî (CD). Using buoyancy control, this device moves alternately up and ...
David C. Jacobs; Charles S. Cox
Determining Turbulent Vertical Velocity, and Fluxes of Heat and Salt with an Autonomous Underwater Vehicle
The authors show that vertical turbulent fluxes in the upper ocean can be measured directly with an autonomous underwater vehicle (AUV). A horizontal profile of vertical water velocity is obtained by applying a Kalman smoother to AUV motion data. ...
Daniel R. Hayes; James H. Morison
Characteristics of Vertical Velocity Cores in Different Convective Systems Observed over Gadanki, India
The Indian mesosphereñstratosphereñtroposphere (MST) radar measurements during the passage of 60 convective systems are used to study the vertical air velocity (w) characteristics of tropical convection. The up- and downdraft cores and various ...
K. N. Uma; T. Narayana Rao
Climatology of Velocity and Temperature Turbulence Statistics Determined from Rawinsonde and ACARS/AMDAR Data
The climatology of the spatial structure functions of velocity and temperature for various altitudes (pressure levels) and latitude bands is constructed from the global rawinsonde network and from Aircraft Communications, Addressing, and ...
Rod Frehlich; Robert Sharman
Ensemble Kalman Filter Assimilation of Simulated HIWRAP Doppler Velocity Data in a Hurricane
This study utilizes ensemble Kalman filter (EnKF) observing system simulation experiments (OSSEs) to analyze the potential impact of assimilating radial velocity observations of hurricanes from the High-altitude Imaging Wind and Rain Airborne ...
Jason A. Sippel; Scott A. Braun; Fuqing Zhang; Yonghui Weng
The Finescale Response of Lowered ADCP Velocity Measurements Processed with Different Methods
In a paper published in 2002 in this journal, K. Polzin et al. derive corrections for spectra of vertical shear calculated from lowered acoustic Doppler current profiler (LADCP) velocity data. To illustrate and validate the corrections, they use ...
A. M. Thurnherr
Velocity Structure of Internal Tide Beams Emanating from Kaena Ridge, Hawaii
Observations are reported of the semidiurnal (M2) internal tide across Kaena Ridge, Hawaii. Horizontal velocity in the upper 1000ñ1500 m was measured during eleven ~240-km-long shipboard acoustic Doppler current profiler (ADCP) transects across ...
Andy Pickering; Matthew H. Alford
Complementarity of weak lensing and peculiar velocity measurements in testing general relativity
We explore the complementarity of weak lensing and galaxy peculiar velocity measurements to better constrain modifications to General Relativity. We find no evidence for deviations from General Relativity on cosmological scales from a combination of peculiar velocity measurements (for Luminous Red Galaxies in the Sloan Digital Sky Survey) with weak lensing measurements (from the Canadian France Hawaii Telescope Legacy Survey). We provide a Fisher error forecast for a Euclid-like space-based survey including both lensing and peculiar velocity measurements and show that the expected constraints on modified gravity will be at least an order of magnitude better than with present data, i.e. we will obtain {approx_equal}5% errors on the modified gravity parametrization described here. We also present a model-independent method for constraining modified gravity parameters using tomographic peculiar velocity information, and apply this methodology to the present data set.
Song, Yong-Seon [Korea Institute for Advanced Study, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of); Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom); Zhao Gongbo; Bacon, David; Koyama, Kazuya; Nichol, Robert C. [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom); Pogosian, Levon [Department of Physics, Simon Fraser University, Burnaby, BC, V5A 1S6 (Canada)
Operational Multiple-Doppler Wind Retrieval Inferred from Long-Range Radial Velocity Measurements
The recent deployment of an innovative triple pulse rise time (PRT) scheme within the French operational radar network allows for the simultaneous collection of reflectivity and radial velocity measurements up to a range of 250 km with no ...
Olivier Bousquet; Pierre Tabary; Jacques Parent du Ch'telet
The upper crustal P-wave velocity structure of Newberry volcano, Central Oregon.
?? The upper-crustal seismic-velocity structure of Newberry volcano, central Oregon, is imaged using P-wave travel time tomography. The inversion combines a densely-spaced seismic line collectedÖ (more)
Beachly, Matthew William
The Upper Crustal P-wave Velocity Structure of Newberry Volcano, Central Oregon.
??The upper-crustal seismic-velocity structure of Newberry volcano, central Oregon, is imaged using P-wave travel time tomography. The inversion combines a densely-spaced seismic line collected inÖ (more)
Beachly, Matthew William, 1986-
Dealiasing Doppler Velocities Measured by a Bistatic Radar Network during a Downburst-Producing Thunderstorm
The object of this paper was to develop an automated dealiasing scheme that dealiases Doppler velocities measured by a bistatic Doppler radar network. The particular network consists of the C-band polarimetric diversity Doppler radar, POLDIRAD, ...
Katja Friedrich; Olivier Caumont
Inversion for subbottom sound velocity profiles in the deep and shallow ocean
This thesis investigates the application of acoustic measurements in the deep and shallow ocean to infer the sound velocity profile (svp) in the seabed. For the deep water ocean, an exact method based on the Gelfand-Levitan ...
Souza, Luiz Alberto Lopes de
Effect of an Insoluble Surface Film on the Drift Velocity of CapillaryñGravity Waves
The drift velocity due to capillary-gravity waves in a deep ocean is investigated theoretically. The surface is covered by an insoluble, inextensible film, and the analysis is based an a Lagrangian description of motion. Attenuated as well as ...
Jan Erik Weber; Even F¯rland
The Temporal-Residual-Mean Velocity. Part I: Derivation and the Scalar Conservation Equations
The time-averaged density conservation equation in z coordinates contains a forcing term that is the divergence of the transient eddy fluxes. These fluxes are due to the temporal correlation between the instantaneous velocity and density fields. ...
Trevor J. McDougall; Peter C. McIntosh
Potential Vorticity and Vertical Velocity at the Iceland-FÊrús Front
Using data from high-resolution surveys of the Iceland- FÊrús Front, the authors have calculated synoptic maps of the geostrophic velocity, vorticity, and potential vorticity on isopycnal surfaces. The data have also been used to diagnose the ...
J. T. Allen; D. A. Smeed
Three-dimensional P and S waves velocity structures of the Coso geothermal
P and S waves velocity structures of the Coso geothermal P and S waves velocity structures of the Coso geothermal area, California, from microseismic travel time data Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Three-dimensional P and S waves velocity structures of the Coso geothermal area, California, from microseismic travel time data Details Activities (1) Areas (1) Regions (0) Abstract: High precision P and S wave travel times for 2104 microearthquakes with focus <6 km are used in a non-linear inversion to derive high-resolution three-dimensional compressional and shear velocity structures at the Coso Geothermal Area in eastern California. Block size for the inversion is 0.2 km horizontally and 0.5 km vertically and inversions are investigated in the upper 5 km of the geothermal area.
USING MICRO-SEISMICITY AND SEISMIC VELOCITIES TO MAP SUBSURFACE GEOLOGIC USING MICRO-SEISMICITY AND SEISMIC VELOCITIES TO MAP SUBSURFACE GEOLOGIC AND HYDROLOGIC STRUCTURE WITHIN THE COSO GEOTHERMAL FIELD, CALIFORNIA Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: USING MICRO-SEISMICITY AND SEISMIC VELOCITIES TO MAP SUBSURFACE GEOLOGIC AND HYDROLOGIC STRUCTURE WITHIN THE COSO GEOTHERMAL FIELD, CALIFORNIA Details Activities (1) Areas (1) Regions (0) Abstract: We relocate 14 years of seismicity in the Coso Geothermal Field using differential travel times and simultaneously invert for seismic velocities to improve our knowledge of the subsurface geologic and hydrologic structure. We utilize over 60,000 micro-seismic events using waveform crosscorrelation to augment the expansive catalog of Pand S-wave
Single-Doppler Velocity Retrievals with Phoenix II Data: Clear Air and Microburst Wind Retrievals in the Planetary Boundary Layer
A new three-dimensional single-Doppler velocity retrieval is introduced and tested with reflectivity and radial velocity data gathered during the Phoenix II field program near Boulder, Colorado. This retrieval is based on reflectivity ...
Alan Shapiro; Scott Ellis; Justin Shaw
Improving Acoustic Doppler Current Profiler Accuracy with Wide-Area Differential GPS and Adaptive Smoothing of Ship Velocity
Accurate ship velocity is important for determining absolute currents from acoustic Doppler current profiler (ADCP) measurements. In this paper, the authors describe the application of two methods to improve the quality of ship velocity ...
Stephen D. Pierce; John A. Barth; Robert L. Smith
The Size Distribution and Mass-Weighted Terminal Velocity of Low-Latitude Tropopause Cirrus Crystal Populations
Ice crystal terminal velocities govern the lifetime of radiatively complex, climatologically important, low-latitude tropopause cirrus clouds. To better understand cloud lifetimes, the terminal velocities of low-latitude tropopause cirrus cloud ...
C. G. Schmitt; A. J. Heymsfield
Laminar burning velocities and flame instabilities of butanol isomers-air mixtures
Laminar burning velocities and flame instabilities of the butanol-air premixed flames and its isomers are investigated using the spherically expanding flame with central ignition at initial temperature of 428 K and initial pressures of 0.10 MPa, 0.25 MPa, 0.50 MPa and 0.75 MPa. Laminar burning velocities and sensitivity factor of n-butanol-air mixtures are computed using a newly developed kinetic mechanism. Unstretched laminar burning velocity, adiabatic temperature, Lewis number, Markstein length, critical flame radius and Peclet number are obtained over a wide range of equivalence ratios. Effect of molecular structure on laminar burning velocity of the isomers of butanol is analyzed from the aspect of C-H bond dissociation energy. Study indicates that although adiabatic flame temperatures of the isomers of butanol are the same, laminar burning velocities give an obvious difference among the isomers of butanol. This indicates that molecular structure has a large influence on laminar burning velocities of the isomers of butanol. Branching (-CH3) will decrease laminar burning velocity. Hydroxyl functional group (-OH) attaching to the terminal carbon atoms gives higher laminar burning velocity compared to that attaching to the inner carbon atoms. Calculated dissociation bond energies show that terminal C-H bonds have larger bond energies than that of inner C-H bonds. n-Butanol, no branching and with hydroxyl functional group (-OH) attaching to the terminal carbon atom, gives the largest laminar burning velocity. tert-Butanol, with highly branching and hydroxyl functional group (-OH) attaching to the inner carbon atom, gives the lowest laminar burning velocity. Laminar burning velocities of iso-butanol and sec-butanol are between those of n-butanol and tert-butanol. The instant of transition to cellularity is experimentally determined for the isomers of butanol and subsequently interpreted on the basis of hydrodynamic and diffusion-thermal instabilities. Little effect on flame instability is observed for the isomers of butanol. Critical flame radii are the same for the isomers of butanol. Peclet number decreases with the increase in equivalence ratio. (author)
Gu, Xiaolei; Huang, Zuohua; Wu, Si; Li, Qianqian [State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049 (China)
Electromagnetic wave propagation with negative phase velocity in regular black holes
We discuss the propagation of electromagnetic plane waves with negative phase velocity in regular black holes. For this purpose, we consider the Bardeen model as a nonlinear magnetic monopole and the Bardeen model coupled to nonlinear electrodynamics with a cosmological constant. It turns out that the region outside the event horizon of each regular black hole does not support negative phase velocity propagation, while its possibility in the region inside the event horizon is discussed.
Coupling between interface and velocity perturbations in the weakly nonlinear Rayleigh-Taylor instability
Weakly nonlinear (WN) Rayleigh-Taylor instability (RTI) initiated by single-mode cosinusoidal interface and velocity perturbations is investigated analytically up to the third order. Expressions of the temporal evolutions of the amplitudes of the first three harmonics are derived. It is shown that there are coupling between interface and velocity perturbations, which plays a prominent role in the WN growth. When the 'equivalent amplitude' of the initial velocity perturbation, which is normalized by its linear growth rate, is compared to the amplitude of the initial interface perturbation, the coupling between them dominates the WN growth of the RTI. Furthermore, the RTI would be mitigated by initiating a velocity perturbation with a relative phase shift against the interface perturbation. More specifically, when the phase shift between the interface perturbation and the velocity perturbation is {pi} and their equivalent amplitudes are equal, the RTI could be completely quenched. If the equivalent amplitude of the initial velocity perturbation is equal to the initial interface perturbation, the difference between the WN growth of the RTI initiated by only an interface perturbation and by only a velocity perturbation is found to be asymptotically negligible. The dependence of the WN growth on the Atwood numbers and the initial perturbation amplitudes is discussed. In particular, we investigate the dependence of the saturation amplitude (time) of the fundamental mode on the Atwood numbers and the initial perturbation amplitudes. It is found that the Atwood numbers and the initial perturbation amplitudes play a crucial role in the WN growth of the RTI. Thus, it should be included in applications where the seeds of the RTI have velocity perturbations, such as inertial confinement fusion implosions and supernova explosions.
Wang, L. F.; Ye, W. H.; He, X. T. [HEDPS and CAPT, Peking University, Beijing 100871 (China); Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Wu, J. F.; Fan, Z. F.; Zhang, W. Y.; Dai, Z. S.; Gu, J. F.; Xue, C. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)
Spin-Orbit Alignment of the TrES-4 Transiting Planetary System and Possible Additional Radial-Velocity Variation
We report new radial velocities of the TrES-4 transiting planetary system, including observations of
Narita, Norio
U.S. Electric Utility Companies and Rates: Look-up by Zipcode...
by NREL and Ventyx, provides average residential, commercial and industrial electricity rates by zip code for both investor owned utilities (IOU) and non-investor owned utilities....
Perry Sioshansi
Global Energy Decisions (GED), now called Ventyx.His recent edited books include Electricity Market Reform: An International Perspective (2006), Competitive Electricity...
Observations of Velocity Conditions near a Hydroelectric Turbine Draft Tube Exit using ADCP Measurements
Measurement of flow characteristics near hydraulic structures is an ongoing challenge because of the need to obtain rapid measurements of time-varying velocity over a relatively large spatial domain. This paper discusses use of an acoustic Doppler current profiler (ADCP) to measure the rapidly diverging flow exiting from an operating hydroelectric turbine draft tube exit. The resolved three-dimensional velocity vectors show a highly complex and helical flow pattern developed near to and downstream of the exit. Velocity vectors were integrated across the exit and we computed an uneven percentage of flow (67%/33%) passing through the two draft tube barrels at a mid-range turbine discharge, consistent with physical model results. In addition to the three-dimensional velocity vectors, the individual one-dimensional velocities measured by each of the four ADCP beams can be separately used as calibration and validation datasets for numerical and physical models. This technique is demonstrated by comparing along-beam ADCP velocity measurements to data collected in a scaled physical model.
Cook, Christopher B.; Richmond, Marshall C.; Serkowski, John A.
Measurement of adiabatic burning velocity in natural gas-like mixtures
Experimental measurements of the adiabatic burning velocities were carried out for natural gas-like mixtures burning in air over a range of equivalence ratios at atmospheric pressure. Effect of CO{sub 2} dilution up to 60%, N{sub 2} dilution up to 40% and 25% enrichment of ethane on burning velocity of methane-air flames were studied. Heat flux method with setup similar to that of [K.J. Bosschaart, L.P.H. de Goey, Detailed analysis of the heat flux method for measuring burning velocity, Combustion and Flame 132 (2003) 170-180] was used for measurement of burning velocities. Initially experiments were done for methane-air and ethane-air mixtures at various equivalence ratios and the results were in good agreement with published data in the literature. Computations were performed using PREMIX code with GRI 3.0 reaction mechanism for all the mixtures. Predicted flame structures were used to the explain the effect of N{sub 2} and CO{sub 2} dilution on burning velocity of methane-air flames. Peak burning velocity for CH{sub 4}/CO{sub 2}-air mixtures occur near to {phi} = 1.0. (author)
Ratna Kishore, V.; Duhan, Nipun; Ravi, M.R.; Ray, Anjan [Department of Mechanical Engineering, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110 016 (India)
Near-Surface Velocity Variability at Inertial and Subinertial Frequencies in the Vicinity of the California Current
Observations of the horizontal velocity field in the upper 150 m, made from the Research Platform FLIP as it drifted of the coast of Baja California, were used to examine the velocity of the velocity field and its relation to local wind forcing. ...
Robert A. Weller
The Defense Nuclear Facilities Safety Board (DNFSB) has recently questioned the appropriate value for tritium deposition velocity used in the MELCOR Accident Consequence Code System Ver. 2 (Chanin and Young 1998) code when estimating bounding dose (95th percentile) for safety analysis (DNFSB 2011). The purpose of this paper is to provide appropriate, defensible values of the tritium deposition velocity for use in Savannah River Site (SRS) safety analyses. To accomplish this, consideration must be given to the re-emission of tritium after deposition. Approximately 85% of the surface area of the SRS is forested. The majority of the forests are pine plantations, 68%. The remaining forest area is 6% mixed pine and hardwood and 26% swamp hardwood. Most of the path from potential release points to the site boundary is through forested land. A search of published studies indicate daylight, tritiated water (HTO) vapor deposition velocities in forest vegetation can range from 0.07 to 2.8 cm/s. Analysis of the results of studies done on an SRS pine plantation and climatological data from the SRS meteorological network indicate that the average deposition velocity during daylight periods is around 0.42 cm/s. The minimum deposition velocity was determined to be about 0.1 cm/s, which is the recommended bounding value. Deposition velocity and residence time (half-life) of HTO in vegetation are related by the leaf area and leaf water volume in the forest. For the characteristics of the pine plantation at SRS the residence time corresponding to the average, daylight deposition velocity is 0.4 hours. The residence time corresponding to the night-time deposition velocity of 0.1 cm/s is around 2 hours. A simple dispersion model which accounts for deposition and re-emission of HTO vapor was used to evaluate the impact on exposure to the maximally exposed offsite individual (MOI) at the SRS boundary (Viner 2012). Under conditions that produce the bounding, 95th percentile MOI exposure, i.e., low wind speed, weak turbulence, night, low deposition velocity, the effect of deposition and re-emission on MOI exposure was found to be very small. The exposure over the two hour period following arrival of the plume was found to be decreased by less than 0.05 %. Furthermore the sensitivity to deposition velocity was low. Increasing deposition velocity to 0.5 cm/s reduced exposure to 0.3 %. After a 24 hour period, an MOI would have been exposed to all of the released material. Based on the low sensitivity of MOI exposure to the value of deposition velocity when re-emission is considered, it is appropriately conservative to use a 0.0 cm/s effective deposition velocity for safety analysis in the MACCS2 code.
Lee, P.; Murphy, C.; Viner, B.; Hunter, C.; Jannik, T.
A Comparison of VHF Radar Vertical-Velocity Measurements by a Direct Vertical-Beam Method and by a VAD Technique
Vertical-velocity measurements made by a direct vertical-beam method are compared to vertical velocities derived from VAD (velocity-azimuth display) measurements over a 27-h period. The results indicate that the two types of measurements in ...
M. F. Larsen; S. Fukao; O. Aruga; M. D. Yamanaka; T. Tsuda; S. Kato
High Energy Tail of the Velocity Distribution of Driven Inelastic Gases
A model of homogeneously driven dissipative system, consisting of a collection of $N$ particles that are characterized by only their velocities, is considered. Adopting a discrete time dynamics, at each time step, a pair of velocities is randomly selected. They undergo inelastic collision with probability $p$. With probability $(1-p)$, energy of the system is changed by changing the velocities of both the particles independently according to $v\\rightarrow -r_w v +\\eta$, where $\\eta$ is a Gaussian noise drawn independently for each particle as well as at each time steps. For the case $r_w=\\pm 1$, although the energy of the system seems to saturate (indicating a steady state) after time steps of O(N), it grows linearly with time after time steps of $O(N^2)$, indicating the absence of a eventual steady state. For $ -1 injection limit, the velocity distribution is shown to be a Gaussian. For the general case, the high energy tail of the velocity distribution is shown to be again a Gaussian, with a different variance.
V. V. Prasad; Sanjib Sabhapandit; Abhishek Dhar
On the Velocity in the Effective Field Theory of Large Scale Structures
We compute the renormalized two-point functions of density, divergence and vorticity of the velocity in the Effective Field Theory of Large Scale Structures. We show that the mass-weighted velocity, as opposed to the volume-weighted velocity, is the natural variable to use. We then prove that, Because of momentum and mass conservation, the corrections from short scales to the large-scale power spectra of density, divergence and vorticity must start at order $k^{4}$. For the vorticity this constitutes the leading term. Exact (approximated) self-similarity of an Einstein-de Sitter ($\\Lambda$CDM) background fixes the time dependence so that the vorticity power spectrum at leading order is uniquely determined, up to a normalization, by the symmetries of the problem. Focusing on density and velocity divergence, we show that the current formulation of the theory does not have enough counterterms to cancel all divergences. At the lowest order, the missing terms are a new stochastic noise and a heat conduction term in the continuity equation. For an Einstein de Sitter universe, we show that all three renormalized cross- and auto-correlation functions have the same structure but different numerical coefficients, which we compute. Using momentum instead of velocity, one can re-absorb the new terms and work with an uncorrected continuity equation but at the cost of having uncancelled IR divergences in equal-time correlators and a more complicated perturbation theory.
Lorenzo Mercolli; Enrico Pajer
Tracking granules at the Sun's surface and reconstructing velocity fields. II. Error analysis
The determination of horizontal velocity fields at the solar surface is crucial to understanding the dynamics and magnetism of the convection zone of the sun. These measurements can be done by tracking granules. Tracking granules from ground-based observations, however, suffers from the Earth's atmospheric turbulence, which induces image distortion. The focus of this paper is to evaluate the influence of this noise on the maps of velocity fields. We use the coherent structure tracking algorithm developed recently and apply it to two independent series of images that contain the same solar signal. We first show that a k-\\omega filtering of the times series of images is highly recommended as a pre-processing to decrease the noise, while, in contrast, using destretching should be avoided. We also demonstrate that the lifetime of granules has a strong influence on the error bars of velocities and that a threshold on the lifetime should be imposed to minimize errors. Finally, although solar flow patterns are easily recognizable and image quality is very good, it turns out that a time sampling of two images every 21 s is not frequent enough, since image distortion still pollutes velocity fields at a 30% level on the 2500 km scale, i.e. the scale on which granules start to behave like passive scalars. The coherent structure tracking algorithm is a useful tool for noise control on the measurement of surface horizontal solar velocity fields when at least two independent series are available.
R. Tkaczuk; M. Rieutord; N. Meunier; T. Roudier
A laboratory investigation was made of the effects of temperature on wave velocities in well cemented Massillon and Boise sandstones and unconsolidated Ottawa sand saturated with heavy hydrocarbons, as well as the dependence of compressional velocities in the hydrocarbons themselves as a function of temperature. The hydrocarbons selected as pore saturants were a commercial paraffin wax, 1-Eicosene, natural heavy crude, and natural tar. The experimental results show that the compressional wave velocities in the hydrocarbons decrease markedly with increasing temperature. In contrast wave velocities in the Massillon and Boise sandstones and unconsolidated Ottawa sand saturated with air or water decrease only little with increasing temperatures. The main reason for the large decreases in rocks with hydrocarbons is the melting of solid hydrocarbons, and high pore pressure. Thermal expansion of the saturants, and possibly thermal cracking of the heavy fractions and vaporization of the light fractions of the hydrocarbons may also contribute. The large decreases of the compressional and shear wave velocities in the hydrocarbon-saturated rocks and sands with temperature, suggest that seismic measurements such as used in seismology or borehole tomography may be very useful in detecting steam fronts in heavy hydrocarbon reservoirs undergoing steam flooding.
Wang, Z.; Nur, A.M.
Stellar velocity dispersions and emission line properties of SDSS-III/BOSS galaxies
We perform a spectroscopic analysis of 492,450 galaxy spectra from the first two years of observations of the Sloan Digital Sky Survey-III/Baryonic Oscillation Spectroscopic Survey (BOSS) collaboration. This data set is released in the ninth SDSS data release in July 2012, the first public data release of BOSS spectra. We show that the typical signal-to-noise ratio of BOSS spectra, despite being low, is sufficient to measure stellar velocity dispersion and emission line fluxes for individual objects. We show that the typical velocity dispersion of a BOSS galaxy is ~240 km/s. The typical error in the velocity dispersion measurement 14 per cent, and 93 per cent of BOSS galaxies have velocity dispersions with an accuracy of better than 30 per cent. The distribution in velocity dispersion is redshift independent between redshifts 0.15 and 0.7, which reflects the survey design targeting massive galaxies with an approximately uniform mass distribution in this redshift interval. The majority of BOSS galaxies lack de...
Thomas, D; Maraston, C; Johansson, J; Beifiori, A; Pforr, J; Strombaeck, G; Tremonti, C A; Wake, D; Bizyaev, D; Bolton, A; Brewington, H; Browstein, J R; Comparat, J; Kneib, J P; Malanushenko, E; Malanushenko, V; Oravetz, D; Pan, K; Parejko, J K; Schneider, D P; Shelden, A; Simmons, A; Snedden, S; Tanaka, M; Weaver, B A; Yan, R
Velocity measurements in the near field of a diesel fuel injector by ultrafast imagery
This paper examines the velocity profile of fuel issuing from a high-pressure single-orifice diesel injector. Velocities of liquid structures were determined from time-resolved ultrafast shadow images, formed by an amplified two-pulse laser source coupled to a double-frame camera. A statistical analysis of the data over many injection events was undertaken to map velocities related to spray formation near the nozzle outlet as a function of time after start of injection. These results reveal a strong asymmetry in the liquid profile of the test injector, with distinct fast and slow regions on opposite sides of the orifice. Differences of ~100 m/s can be observed between the 'fast' and 'slow' sides of the jet, resulting in different atomization conditions across the spray. On average, droplets are dispersed at a greater distance from the nozzle on the 'fast' side of the flow, and distinct macrostructure can be observed under the asymmetric velocity conditions. The changes in structural velocity and atomization b...
In-Situ Continuous Detonation Velocity Measurements Using Fiber-optic Bragg Grating Sensors
In order to fully calibrate hydrocodes and dynamic chemistry burn models, initiation and detonation research requires continuous measurement of low order detonation velocities as the detonation runs up to full order detonation for a given density and initiation pressure pulse. A novel detector of detonation velocity is presented using a 125 micron diameter optical fiber with an integral chirped fiber Bragg grating as an intrinsic sensor. This fiber is embedded in the explosive under study and interrogated during detonation as the fiber Bragg grating scatters light back along the fiber to a photodiode, producing a return signal dependant on the convolution integral of the grating reflection bandpass, the ASE intensity profile and the photodetector response curve. Detonation velocity is measured as the decrease in reflected light exiting the fiber as the grating is consumed when the detonation reaction zone proceeds along the fiber sensor axis. This small fiber probe causes minimal perturbation to the detonation wave and can measure detonation velocities along path lengths tens of millimeters long. Experimental details of the associated equipment and preliminary data in the form of continuous detonation velocity records within nitromethane and PBX-9502 are presented.
Benterou, J; Udd, E; Wilkins, P; Roeske, F; Roos, E; Jackson, D
Doppler cooling with coherent trains of laser pulses and a tunable velocity comb
We explore the possibility of decelerating and Doppler cooling an ensemble of two-level atoms by a coherent train of short, nonoverlapping laser pulses. We derive analytical expressions for mechanical force exerted by the train. In frequency space the force pattern reflects the underlying frequency comb structure. The pattern depends strongly on the ratio of the atomic lifetime to the repetition time between the pulses and pulse area. For example, in the limit of short lifetimes, the frequency-space peaks of the optical force wash out. We propose to tune the carrier-envelope offset frequency to follow the Doppler-shifted detuning as atoms decelerate; this leads to compression of atomic velocity distribution about comb teeth and results in a ''velocity comb''--a series of narrow equidistant peaks in the velocity space.
Ilinova, Ekaterina; Ahmad, Mahmoud; Derevianko, Andrei [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States)
Doping-Dependent Nodal Fermi Velocity in Bi-2212 Revealed by High-Resolution ARPES
The improved resolution of laser-based angle-resolved photoemission spectroscopy (ARPES) allows reliable access to fine structures in the spectrum. We present a systematic, doping-dependent study of a recently discovered low-energy kink in the nodal dispersion of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi-2212), which demonstrates the ubiquity and robustness of this kink in underdoped Bi-2212. The renormalization of the nodal velocity due to this kink becomes stronger with underdoping, revealing that the nodal Fermi velocity is non-universal, in contrast to assumed phenomenology. This is used together with laser-ARPES measurements of the gap velocity, v{sub 2}, to resolve discrepancies with thermal conductivity measurements.
Vishik, I. M.
Very lean hydrogen-air mixtures experience strong diffusive-thermal types of cellular instabilities that tend to increase the laminar burning velocity above the value that applies to steady, planar laminar flames that are homogeneous in transverse directions. Flame balls constitute an extreme limit of evolution of cellular flames. To account qualitatively for the ultimate effect of diffusive-thermal instability, a model is proposed in which the flame is a steadily propagating, planar, hexagonal, close-packed array of flame balls, each burning as if it were an isolated, stationary, ideal flame ball in an infinite, quiescent atmosphere. An expression for the laminar burning velocity is derived from this model, which theoretically may provide an upper limit for the experimental burning velocity.
Williams, Forman; Williams, Forman A; Grcar, Joseph F
THE MILKY WAY'S CIRCULAR-VELOCITY CURVE BETWEEN 4 AND 14 kpc FROM APOGEE DATA
We measure the Milky Way's rotation curve over the Galactocentric range 4 kpc {approx}data from the Apache Point Observatory Galactic Evolution Experiment. We model the line-of-sight velocities of 3365 stars in 14 fields with b = 0 Degree-Sign between 30 Degree-Sign {99 % confidence. We find an offset between the Sun's rotational velocity and the local circular velocity of 26 {+-} 3 km s{sup -1}, which is larger than the locally measured solar motion of 12 km s{sup -1}. This larger offset reconciles our value for V{sub c} with recent claims that V{sub c} {approx}> 240 km s{sup -1}. Combining our results with other data, we find that the Milky Way's dark-halo mass within the virial radius is {approx}8 Multiplication-Sign 10{sup 11} M {sub Sun }.
Bovy, Jo [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Allende Prieto, Carlos; Meszaros, Szabolcs [Instituto de Astrofisica de Canarias (IAC), E-38200 La Laguna, Tenerife (Spain); Beers, Timothy C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Bizyaev, Dmitry; Ebelke, Garrett L.; Malanushenko, Elena; Malanushenko, Viktor [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Da Costa, Luiz N.; Girardi, Leo; Maia, Marcio A. G. [Laboratorio Interinstitucional de e-Astronomia-LIneA, Rua Gal. Jose Cristino 77, Rio de Janeiro, RJ 20921-400 (Brazil); Cunha, Katia [Observatorio Nacional, Rio de Janeiro, RJ 20921-400 (Brazil); Eisenstein, Daniel J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS 20, Cambridge, MA 02138 (United States); Frinchaboy, Peter M. [Department of Physics and Astronomy, Texas Christian University, Fort Worth, TX 76129 (United States); Garcia Perez, Ana Elia; Hearty, Fred R.; Majewski, Steven R.; Nidever, David L. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Hogg, David W. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Holtzman, Jon, E-mail: firstname.lastname@example.com [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States); and others
Design of passively aerated compost piles: Vertical air velocities between the pipes
Passively aerated compost piles are built on a base of porous materials, such as straw or wood chips, in which perforated air supply pipes are distributed. The piles are not turned during composting, nor is forced-aeration equipment used, which significantly reduces the operating and capital expenses associated with these piles. Currently, pile configurations and materials are worked out by trial and error. Fundamentally based design procedures are difficult to develop because the natural convection air flow rate is not explicitly known, but rather is closely coupled with the pile temperature. This paper develops a mathematical model to analytically determine the maximum upward air flow velocity over an air supply pipe and the drop in vertical velocity away from the pipe. This model has one dimensionless number, dependent on the pile and base properties, which fully characterizes the velocity profile between the pipes. 9 refs., 4 figs., 1 tab.
Lynch, N.J.; Cherry, R.S. [Idaho National Engineering Lab., Idaho Falls, ID (United States)
Acoustic Doppler Current Profiler Surveys of Velocity Downstream of Albeni Falls Dam
The U.S. Army Corps of Engineers (USACE), Seattle District, is studying the potential to locate fish bypass systems at Albeni Falls Dam. The USACE requested Pacific Northwest National Laboratory (PNNL) to survey velocity magnitude and direction in the dam tailrace. The empirical data collected will be used to support future numerical modeling, physical modeling, and evaluation of fish bypass system alternatives. In May 2010, PNNL conducted velocity surveys of the Albeni Falls Dam using a boat-mounted acoustic Doppler current profiler. The surveys were conducted over three days (May 25 through 27). During the survey period, total river discharge at the dam varied between 30.2 and 31.0 kcfs. A small amount of spill discharge, 2 kcfs, was present on two days (May 26 and 27). This report presents data plots showing measured velocity direction and magnitude averaged over the entire depth and over 5-ft depth increments from 5 to 30 ft.
Perkins, William A.; Titzler, P. Scott; Richmond, Marshall C.; Serkowski, John A.; Kallio, Sara E.; Bellgraph, Brian J.
Seismic velocity structure and microearthquake source properties at The Geysers, California, geothermal area
The method of progressive hypocenter-velocity inversion has been extended to incorporate S-wave arrival time data and to estimate S-wave velocities in addition to P-wave velocities. S-wave data to progressive inversion does not completely eliminate hypocenter-velocity tradeoffs, but they are substantially reduced. Results of a P and S-wave progressive hypocenter-velocity inversion at The Geysers show that the top of the steam reservoir is clearly defined by a large decrease of V/sub p//V/sub s/ at the condensation zone-production zone contact. The depth interval of maximum steam production coincides with minimum observed V/sub p//V/sub s/, and V/sub p//V/sub s/ increses below the shallow primary production zone suggesting that reservoir rock becomes more fluid saturated. The moment tensor inversion method was applied to three microearthquakes at The Geysers. Estimated principal stress orientations were comparable to those estimated using P-wave firstmotions as constraints. Well constrained principal stress orientations were obtained for one event for which the 17 P-first motions could not distinguish between normal-slip and strike-slip mechanisms. The moment tensor estimates of principal stress orientations were obtained using far fewer stations than required for first-motion focal mechanism solutions. The three focal mechanisms obtained here support the hypothesis that focal mechanisms are a function of depth at The Geysers. Progressive inversion as developed here and the moment tensor inversion method provide a complete approach for determining earthquake locations, P and S-wave velocity structure, and earthquake source mechanisms.
O'Connell, D.R.
A 4-spot time-of-flight anemometer for small centrifugal compressor velocity measurements
The application of laser anemometry techniques in turbomachinery facilities is a challenging dilemma requiring an anemometer system with special qualities. Here, we describe the use of a novel laser anemometry technique applied to a small 4.5 kg/s, 4:1 pressure ratio centrifugal compressor. Sample velocity profiles across the blade pitch are presented for a single location along the rotor. The results of the intra-blade passage velocity measurements will ultimately be used to verify CFD 3-D viscous code predictions.
Wernet, M.P.; Skoch, G.J.
Moment preserving adaptive particle weights using octree velocity distributions for PIC simulations
The ratio of computational to physical particles is of primary concern to statistical particle based simulations such as DSMC and PIC. An adaptive computational particle weight algorithm is presented that conserves mass, momentum, and energy. This algorithm is then enhanced with an octree adaptive mesh in velocity space to mitigate artificial thermalization. The new octree merge is compared to a merge that randomly selects merge partners for a bi-Maxwellian velocity distribution. Results for crossing beams in a fixed potential well along with an electrostatic PIC version with and without MCC collisions based ionizing breakdown show the advantages of the merge algorithm to both fixed particle weights and randomly selected merge partners.
Martin, Robert Scott; Cambier, Jean-Luc [ERC Inc. (United States); Spacecraft Propulsion Branch, Air Force Research Laboratory, Edwards AFB, CA 93524 (United States)
Group velocity of extraordinary waves in superdense magnetized quantum plasma with spin-1/2 effects
Based on the one component plasma model, a new dispersion relation and group velocity of elliptically polarized extraordinary electromagnetic waves in a superdense quantum magnetoplasma are derived. The group velocity of the extraordinary wave is modified due to the quantum forces and magnetization effects within a certain range of wave numbers. It means that the quantum spin-1/2 effects can reduce the transport of energy in such quantum plasma systems. Our work should be of relevance for the dense astrophysical environments and the condensed matter physics.
Li Chunhua; Ren Haijun; Yang Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu Zhengwei [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)
A Sensor-based Long Baseline Position and Velocity Navigation Filter for Underwater Vehicles
This paper presents a novel Long Baseline (LBL) position and velocity navigation filter for underwater vehicles based directly on the sensor measurements. The solution departs from previous approaches as the range measurements are explicitly embedded in the filter design, therefore avoiding inversion algorithms. Moreover, the nonlinear system dynamics are considered to their full extent and no linearizations are carried out whatsoever. The filter error dynamics are globally asymptotically stable (GAS) and it is shown, under simulation environment, that the filter achieves similar performance to the Extended Kalman Filter (EKF) and outperforms linear position and velocity filters based on algebraic estimates of the position obtained from the range measurements.
Batista, Pedro; Oliveira, Paulo
Nonlinear pulse propagation and phase velocity of laser-driven plasma waves
Laser evolution and plasma wave excitation by a relativistically-intense short-pulse laser in underdense plasma are investigated in the broad pulse limit, including the effects of pulse steepening, frequency red-shifting, and energy depletion. The nonlinear plasma wave phase velocity is shown to be significantly lower than the laser group velocity and further decreases as the pulse propagates owing to laser evolution. This lowers the thresholds for trapping and wavebreaking, and reduces the energy gain and efficiency of laser-plasma accelerators that use a uniform plasma profile.
Schroeder, Carl B.; Benedetti, Carlo; Esarey, Eric; Leemans, Wim
The presence of interstellar turbulence could explain the velocity flattening in galaxies
Expanding our previous work on turbulent whirls [1] we have uncovered a similarity within the similarity shared by intense vortices. Using the new information we compress the tangential velocity profiles of a diverse set of vortices into one and thus identify those that belong to the same genus. Examining the Laser Doppler Anemometer (LDA) results of mechanically produced vortices and radar data of several tropical cyclones, we find that the uplift and flattening effect of tangential velocity is a consequence of turbulence. Reasoning by analogy we conclude that turbulence in the interstellar medium could indeed introduce a flattening effect in the galactic rotation curves.
Vatistas, Georgios H
Velocity and Timing of Multiple Spherically Converging Shock Waves in Liquid Deuterium
The fuel entropy and required drive energy for an inertial confinement fusion implosion are set by a sequence of shocks that must be precisely timed to achieve ignition. This Letter reports measurements of multiple spherical shock waves in liquid deuterium that facilitate timing inertial confinement fusion shocks to the required precision. These experiments produced the highest shock velocity observed in liquid deuterium (U{sub s}=135 km/s at {approx}2500 GPa) and also the first observation of convergence effects on the shock velocity. Simulations model the shock-timing results well when a nonlocal transport model is used in the coronal plasma.
Boehly, T. R.; Goncharov, V. N.; Seka, W.; Hu, S. X.; Marozas, J. A. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Barrios, M. A.; Celliers, P. M.; Hicks, D. G.; Collins, G. W. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Meyerhofer, D. D. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Departments of Mechanical Engineering and Physics, University of Rochester, Rochester, New York 14623 (United States)
Three-dimensional p-velocity structure of the summit caldera of Newberry Volcano, Oregon
A three-dimensional high-resolution seismic study of the summit caldera of Newberry Volcano, Oregon, was conducted by the US Geological Survey using an adaptation of the method applied by Mercessian et al. (1984). Preliminary interpretation of the traveltime residuals reveals a ring of high P-velocity material coinciding with the inner ring fault system of the caldera in the upper 2 km. A zone of lower P velocities extends deeper than 2 km in the center of the caldera. 9 refs., 5 figs.
Stauber, D.A.; Iyer, N.M.; Mooney, W.D.; Dawson, P.B.
Deposition Velocities of Newtonian and Non-Newtonian Slurries in Pipelines
The WTP pipe plugging issue, as stated by the External Flowsheet Review Team (EFRT) Executive Summary, is as follows: ìPiping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.î A strategy was employed to perform critical-velocity tests on several physical simulants. Critical velocity is defined as the point where a stationary bed of particles deposits on the bottom of a straight horizontal pipe during slurry transport operations. Results from the critical velocity testing provide an indication of slurry stability as a function of fluid rheological properties and transport conditions. The experimental results are compared to the WTP design guide on slurry transport velocity in an effort to confirm minimum waste velocity and flushing velocity requirements as established by calculations and critical line velocity correlations in the design guide. The major findings of this testing is discussed below. Experimental results indicate that the use of the Oroskar and Turian (1980) correlation in the design guide is conservativeóSlurry viscosity has a greater affect on particles with a large surface area to mass ratio. The increased viscous forces on these particles result in a decrease in predicted critical velocities from this traditional industry derived equations that focus on particles large than 100 ?m in size. Since the Hanford slurry particles generally have large surface area to mass ratios, the reliance on such equations in the Hall (2006) design guide is conservative. Additionally, the use of the 95% percentile particle size as an input to this equation is conservative. However, test results indicate that the use of an average particle density as an input to the equation is not conservative. Particle density has a large influence on the overall result returned by the correlation. Lastly, the viscosity correlation used in the WTP design guide has been shown to be inaccurate for Hanford waste feed materials. The use of the Thomas (1979) correlation in the design guide is not conservativeóIn cases where 100% of the particles are smaller than 74 ?m or particles are considered to be homogeneous due to yield stress forces suspending the particles the homogeneous fraction of the slurry can be set to 100%. In such cases, the predicted critical velocity based on the conservative Oroskar and Turian (1980) correlation is reduced to zero and the design guide returns a value from the Thomas (1979) correlation. The measured data in this report show that the Thomas (1979) correlation predictions often fall below that measured experimental values. A non-Newtonian deposition velocity design guide should be developed for the WTPó Since the WTP design guide is limited to Newtonian fluids and the WTP expects to process large quantities of such materials, the existing design guide should be modified address such systems. A central experimental finding of this testing is that the flow velocity required to reach turbulent flow increases with slurry rheological properties due to viscous forces dampening the formation of turbulent eddies. The flow becomes dominated by viscous forces rather than turbulent eddies. Since the turbulent eddies necessary for particle transport are not present, the particles will settle when crossing this boundary called the transitional deposition boundary. This deposition mechanism should be expected and designed for in the WTP.
Poloski, Adam P.; Adkins, Harold E.; Abrefah, John; Casella, Andrew M.; Hohimer, Ryan E.; Nigl, Franz; Minette, Michael J.; Toth, James J.; Tingey, Joel M.; Yokuda, Satoru T.
Lithospheric Velocity Structure of the Anatolain plateau-Caucasus-Caspian Regions
Anatolian Plateau-Caucasus-Caspian region is an area of complex structure accompanied by large variations in seismic wave velocities. Despite the complexity of the region little is known about the detailed lithospheric structure. Using data from 29 new broadband seismic stations in the region, a unified velocity structure is developed using teleseismic receiver functions and surface waves. Love and Rayleigh surface waves dispersion curves have been derived from event-based analysis and ambient-noise correlation. We jointly inverted the receiver functions with the surface wave dispersion curves to determine absolute shear wave velocity and important discontinuities such as sedimentary layer, Moho, lithospheric-asthenospheric boundary. We combined these new station results with Eastern Turkey Seismic Experiment results (29 stations). Caspian Sea and Kura basin underlained by one of the thickest sediments in the world. Therefore, short-period surface waves are observed to be very slow. The strong crustal multiples in receiver functions and the slow velocities in upper crust indicate the presence of thick sedimentary unit (up to 20 km). Crustal thickness varies from 34 to 52 km in the region. The thickest crust is in Lesser Caucasus and the thinnest is in the Arabian Plate. The lithospheric mantle in the Greater Caucasus and the Kura depression is faster than the Anatolian Plateau and Lesser Caucasus. This possibly indicates the presence of cold lithosphere. The lower crust is slowest in the northeastern part of the Anatolian Plateau where Holocene volcanoes are located.
Gok, R; Mellors, R J; Sandvol, E; Pasyanos, M; Hauk, T; Yetirmishli, G; Teoman, U; Turkelli, N; Godoladze, T; Javakishvirli, Z
Wind Velocities at the Chajnantor and Mauna Kea Sites and the Effect on MMA Pointing
Wind Velocities at the Chajnantor and Mauna Kea Sites and the Effect on MMA Pointing M.A. Holdaway email: (mholdawa, sfoster, demerson, jcheng, fschwab)@nrao.edu August 9, 1996 Abstract We analyze wind April 1996 for the purposes of understanding the effects of the winds on pointing errors. Both
Groppi, Christopher
Direct detection and solar capture of dark matter with momentum and velocity dependent elastic scattering
We explore the momentum and velocity dependent elastic scattering between the dark matter (DM) particles and the nuclei in detectors and the Sun. In terms of the non-relativistic effective theory, we phenomenologically discuss ten kinds of momentum and velocity dependent DM-nucleus interactions and recalculate the corresponding upper limits on the spin-independent DM-nucleon scattering cross section from the current direct detection experiments. The DM solar capture rate is calculated for each interaction. Our numerical results show that the momentum and velocity dependent cases can give larger solar capture rate than the usual contact interaction case for almost the whole parameter space. On the other hand, we deduce the Super-Kamiokande's constraints on the solar capture rate for eight typical DM annihilation channels. In contrast to the usual contact interaction, the Super-Kamiokande and IceCube experiments can give more stringent limits on the DM-nucleon elastic scattering cross section than the current direct detection experiments for several momentum and velocity dependent DM-nucleus interactions. In addition, we investigate the mediator mass's effect on the DM elastic scattering cross section and solar capture rate.
Wan-Lei Guo; Zheng-Liang Liang; Yue-Liang Wu
Local Equation of State and Velocity Distributions of a Driven Granular Gas
We present event-driven simulations of a granular gas of inelastic hard disks with incomplete normal restitution in two dimensions between vibrating walls (without gravity). We measure hydrodynamic quantities such as the stress tensor, density and temperature profiles, as well as velocity distributions. Relating the local pressure to the local temperature and local density, we construct a local constitutive equation. For strong inelasticities the local constitutive relation depends on global system parameters, like the volume fraction and the aspect ratio. For moderate inelasticities the constitutive relation is approximately independent of the system parameters and can hence be regarded as a local equation of state, even though the system is highly inhomogeneous with heterogeneous temperature and density profiles arising as a consequence of the energy injection. Concerning the local velocity distributions we find that they do not scale with the square root of the local granular temperature. Moreover the high-velocity tails are different for the distribution of the x- and the y-component of the velocity, and even depend on the position in the sample, the global volume fraction, and the coefficient of restitution.
Olaf Herbst; Peter M¸ller; Matthias Otto; Annette Zippelius
Shock initiation studies of low density HMX using electromagnetic particle velocity and PVDF stress gauges
Magnetic particle velocity and PVDF stress rate gauges have been used to measure the shock response of low density octotetramethylene tetranitramine (HMX) (1.24 &/cm{sup 3}). In experiments done at LANL, magnetic particle velocity gauges were located on both sides of the explosive. In nearly identical experiments done at SNL, PVDF stress rate gauges were located at the same positions so both particle velocity and stress histories were obtained for a particular experimental condition. Unreacted Hugoniot data were obtained and an EOS was developed by combining methods used by Hayes, Sheffield and Mitchell (for describing the Hugoniot of HNS at various densities) with Hermann`s P-{alpha} model. Using this technique, it is only necessary to know some thermodynamic constants or the Hugoniot of the initially solid material and the porous material sound speed to obtain accurate unreacted Hugoniots for the porous explosive. Loading and reaction paths were established in the stress-particle velocity plane for some experimental conditions. This information was used to determine a global reaction rate of {approx} 0.13 {mu}s{sup {minus}1} for porous HMX shocked to 0.8 GPa. At low input stresses the transmitted wave profiles had long rise times (up to 1 {mu}s) due to the compaction processes.
Sheffield, S.A.; Gustavsen, R.L.; Alcon, R.R. [Los Alamos National Lab., NM (United States); Graham, R.A.; Anderson, M.U. [Sandia National Labs., Albuquerque, NM (United States)
Velocity-jump processes with a finite number of speeds and their asymptotically parabolic nature
Velocity-jump processes with a finite number of speeds and their asymptotically parabolic nature-time behavior is described by a corresponding scalar diffusive equation of parabolic type, defined, alternative to the tradi- tional parabolic heat equation, which, on the contrary, mantains the inherent
Velocity Biases of Adaptive Filter Estimates in Heterodyne Doppler Lidar Measurements
Frequency estimates by heterodyne Doppler lidar (HDL) may result in velocity bias due to the atmospheric speckle effect and an asymmetrical power spectrum of the probing pulse, as discussed in a previous paper by Dabas et al. In this paper, it ...
A Photoelectric Technique for Measuring Lightning-Channel Propagation Velocities from a Mobile Laboratory
We have developed a device to measure lightning-channel propagation velocities. It consists of eight solid state silicon photodetectors mounted behind precision horizontal slits in the focal plane of a 50-mm lens on a 35-mm camera body. Each ...
Douglas M. Mach; W. David Rust
Reconstructing Basin-Scale Eulerian Velocity Fields from Simulated Drifter Data
A single-layer, reduced-gravity, double-gyre primitive equation model in a 2000 km ◊ 2000 km square domain is used to test the accuracy and sensitivity of time-dependent Eulerian velocity fields reconstructed from numerically generated drifter ...
M. Toner; A. D. Kirwan Jr.; B. L. Lipphardt; A. C. Poje; C. K. R. T. Jones; C. E. Grosch
Uncertainty in a Path-averaged Measurement of the Friction Velocity u*
Several electro-optical methods exist for measuring a path-averaged value of the inner scale of turbulence l0. By virtue of MoninñObukhov similarity, in the atmospheric surface layer such l0 measurements are related to the friction velocity u* or ...
Edgar L. Andreas
Effects of Wave Breaking on the Near-Surface Profiles of Velocity and Turbulent Kinetic Energy
A theoretical model for the near-surface velocity profile in the presence of breaking waves is presented. Momentum is accumulated by growing waves and is released upon wave breaking. In effect, such a transition is a process involving a time-...
Arne Melsom; ÿyvind S∆tra
The mean velocity of two-state models of molecular motor
The motion of molecular motor is essential to the biophysical functioning of living cells. In principle, this motion can be regraded as a multiple chemical states process. In which, the molecular motor can jump between different chemical states, and in each chemical state, the motor moves forward or backward in a corresponding potential. So, mathematically, the motion of molecular motor can be described by several coupled one-dimensional hopping models or by several coupled Fokker-Planck equations. To know the basic properties of molecular motor, in this paper, we will give detailed analysis about the simplest cases: in which there are only two chemical states. Actually, many of the existing models, such as the flashing ratchet model, can be regarded as a two-state model. From the explicit expression of the mean velocity, we find that the mean velocity of molecular motor might be nonzero even if the potential in each state is periodic, which means that there is no energy input to the molecular motor in each of the two states. At the same time, the mean velocity might be zero even if there is energy input to the molecular motor. Generally, the velocity of molecular motor depends not only on the potentials (or corresponding forward and backward transition rates) in the two states, but also on the transition rates between the two chemical states.
Yunxin Zhang
Velocity-Dependent Friction and Diffusion for Grains in Neutral Gases, Dusty Plasmas and Active Systems
A self-consistent and universal description of friction and diffusion for Brownian particles (grains) in different systems, as a gas with Boltzmann collisions, dusty plasma with ion absorption by grains, and for active particles (e.g., cells in biological systems) is suggested on the basis of the appropriate Fokker-Planck equation. Restrictions for application of the Fokker-Planck equation to the problem of velocity-dependent friction and diffusion coefficients are found. General description for this coefficient is formulated on the basis of master equation. Relation of the diffusion coefficient in the coordinate and velocity spaces is found for active (capable to transfer momentum to the ambient media) and passive particles in the framework of the Fokker-Planck equation. The problem of anomalous space diffusion is formulated on the basis of the appropriate probability transition (PT) function. The method of partial differentiation is avoided to construct the correct probability distributions for arbitrary distances, what is important for applications to different stochastic problems. Generale equation for time-dependent PT function is formulated and discussed. Generalized friction in the velocity space is determined and applied to describe the friction force itself as well as the drag force in the case of a non-zero driven ion velocity in plasmas. The negative friction due to ion scattering on grains exists and can be realized for the appropriate experimental conditions.
S. A. Trigger; G. J. F. van Heijst; P. P. J. M. Schram
S. A. Trigger; G. J. F. Van Heijst; P. P. J. M. Schram
A study of swirl and axial velocity profile effects on orifice flowmeters
The objective of this study is to measure the response of the orifice meter to known upstream flow field disturbances generated by a concentric tube flow conditioner and a vane-type swirl generator. These disturbances are characterized by flan measuring the axial and tangential velocity profiles at the upstream tap with no orifice plate present. Two different flow rates are examined which correspond to Reynolds numbers of 91,100 and 120,000 in a 50.8 mm diameter pipe. Eight orifice plates with [ ] ratios of 0.43, 0.45, 0.484, 0.55, 0.6, 0.65, 0.7 and 0.726 are studied at both flow rates. The response of each orifice meter to the disturbance is measured by determining the axial pressure distribution near the orifice plate, and by determining the discharge coefficient. The axial momentum distribution is quantified by calculating the second order moment of axial momentum (91 2[U]) from the velocity profile data. Swirl is quantified by determining the centripetal acceleration flux of the flow, also from the velocity profile data. Surface fits indicating the variation of discharge coefficient as a function of P ratio and 9i2[U] or swirl number are developed. These are useful in evaluating variations in the discharge coefficient for flows where the inlet velocity profile has been measured.
Hauglie, Jayden Edward
A Modified Multivariate MaddenñJulian Oscillation Index Using Velocity Potential
A new MaddenñJulian oscillation (MJO) index is developed from a combined empirical orthogonal function (EOF) analysis of meridionally averaged 200-hPa velocity potential (VP200), 200-hPa zonal wind (U200), and 850-hPa zonal wind (U850). Like the ...
Michael J. Ventrice; Matthew C. Wheeler; Harry H. Hendon; Carl J. Schreck III; Chris D. Thorncroft; George N. Kiladis
1 A HYPOTHETICAL BURNING-VELOCITY FORMULA FOR VERY LEAN HYDROGEN-AIR MIXTURES by Forman A. Williams experience strong diffusive-thermal types of cellular instabilities that tend to increase the laminar burning propagating, planar, hexagonal, close-packed array of flame balls, each burning as if it were an isolated
Geddes, Cameron Guy Robinson
We present a hierarchical Bayesian determination of the velocity-dispersion function of approximately 430,000 massive luminous red galaxies observed at relatively low spectroscopic signal-to-noise ratio (S/N {approx} 3-5 per 69 km s{sup -1}) by the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III. We marginalize over spectroscopic redshift errors, and use the full velocity-dispersion likelihood function for each galaxy to make a self-consistent determination of the velocity-dispersion distribution parameters as a function of absolute magnitude and redshift, correcting as well for the effects of broadband magnitude errors on our binning. Parameterizing the distribution at each point in the luminosity-redshift plane with a log-normal form, we detect significant evolution in the width of the distribution toward higher intrinsic scatter at higher redshifts. Using a subset of deep re-observations of BOSS galaxies, we demonstrate that our distribution-parameter estimates are unbiased regardless of spectroscopic S/N. We also show through simulation that our method introduces no systematic parameter bias with redshift. We highlight the advantage of the hierarchical Bayesian method over frequentist 'stacking' of spectra, and illustrate how our measured distribution parameters can be adopted as informative priors for velocity-dispersion measurements from individual noisy spectra.
Shu Yiping; Bolton, Adam S.; Dawson, Kyle S.; Brownstein, Joel R. [Department of Physics and Astronomy, University of Utah, 115 South 1400 East, Salt Lake City, UT 84112 (United States); Schlegel, David J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Wake, David A. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Brinkmann, Jon [Apache Point Observatory, Apache Point Road, P.O. Box 59, Sunspot, NM 88349 (United States); Weaver, Benjamin A., E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com [Center for Cosmology and Particle Physics, New York University, NY 10003 (United States)
Proceedings: Evolution of Large Scale Structure --Garching, August 1998 THE EFAR PECULIAR VELOCITY FIELD
determinations, and used to determine the peculiar velocities (PV) of the clusters. We find that the mean detected lo cally (LyndenBell et al. 1988), and therefore is a sensitive test of cosmo logical models and bulge components of the galaxies are also available, allow ing a reliable morphological classifi
Saglia, Roberto P.
Measurements of the bulk and interfacial velocity profiles in oscillating Newtonian and Maxwellian fluids
We present the dynamic velocity profiles of a Newtonian fluid (glycerol) and a viscoelastic Maxwell fluid (CPyCl/NaSal in water) driven by an oscillating pressure gradient in a vertical cylindrical pipe. The frequency range explored has been chosen to include the first three resonance peaks of the dynamic permeability of the viscoelastic fluid / pipe system. Three different optical measurement techniques have been employed. Laser Doppler Anemometry has been used to measure the magnitude of the velocity at the centre of the liquid column. Particle Image Velocimetry and Optical Deflectometry are used to determine the velocity profiles at the bulk of the liquid column and at the liquid--air interface respectively. The velocity measurements in the bulk are in good agreement with the theoretical predictions of a linear theory. The results, however, show dramatic differences in the dynamic behaviour of Newtonian and viscoelastic fluids, and demonstrate the importance of resonance phenomena in viscoelastic fluid flows, biofluids in particular, in confined geometries.
M. Torralba; J. R. Castrejon-Pita; A. A. Castrejon-Pita; G. Huelsz; J. A. del Rio; J. Ortin
Fall Velocities of Hydrometeors in the Atmosphere: Refinements to a Continuous Analytical Power Law
This paper extends the previous research of the authors on the unified representation of fall velocities for both liquid and crystalline particles as a power law over the entire size range of hydrometeors observed in the atmosphere. The power-law ...
High velocity impact of metal sphere on thin metallic plates: a comparative smooth particle hydrodynamics study
Four different shock-capturing schemes used in smooth particle hydrodynamics are compared as applied to moderately high-velocity impacts (at 3 km/s) and hypervelocity impacts (at ?6 km/s) of metallic projectiles on thin metal plates. The target ... Keywords: Riemann problem, artificial viscosity, hydrocode, hypervelocity impact
Vishal Mehra; Shashank Chaturvedi
Real time mass flux measurements of gas-solid suspensions at low velocities
In previous work, measurement of the particulate mass flux was made based upon a novel electrostatic technique. A small conducting wire sensor was inserted in the flow and as each particle hit the sensor an individual pulse of current was identified. Through suitable electronic circuitry, the number of pulses in a given time were counted. This was a direct measure of the number of particle-probe collisions which was related to local particle mass flow. The technique is currently limited to monodisperse suspensions. A primary advantage of the impact counter system is that the output does not depend upon the magnitude of the actual charge transfer. As long as the pulses are sufficiently above the noise level, variations in charge transfer will not affect the measurement. For the current work, the technique was applied to vertical gas-solid flow where the fluid velocity was slightly above the particle terminal velocity. Under these conditions a sufficient signal to noise ratio was not found. The Cheng-Soo charge transfer theory indicated that the low particle-sensor impact velocity was responsible. The probe system was then modified by extracting a particulate sample isokinetically and accelerating the particles to a sufficient velocity by an area reduction in the sampling tube. With this technique the signal to noise ratio was about 12 to 1. Mass flux results are shown to compare favorably with filter collection and weighing.
Saunders, J H; Chao, B T; Soo, S L
Temporal and Spatial Aspects of Velocity Variance in the Urban Surface Roughness Layer
Data from six urban areas in a nationwide network of sites within the surface roughness layer are examined. It is found that the average velocity variances in time, derived by averaging the conventional variances from a network of n stations, are ...
Bruce B. Hicks; Elena Novakovskaia; Ronald J. Dobosy; William R. Pendergrass III; William J. Callahan
Probing High-Velocity Transient-Field Strength Using Heavy-ions Traversing Fe and Gd
The transient field strength for {sup 76}Ge ions, passing through iron and gadolinium layers at velocities approxZv{sub 0}, has been measured. Although a sizeable value has been obtained for Gd, a vanishing strength has been observed in Fe.
Fiori, E.; Georgiev, G.; Cabaret, S.; Lozeva, R. [CSNSM, CNRS/IN2P3, Universite Paris-Sud 11, UMR8609, F-91405 ORSAY-Campus (France); Stuchbery, A. E. [Department of Nuclear Physics, Australian National University, Canberra (Australia); Jungclaus, A.; Modamio, V.; Walker, J. [Instituto de Estructura de la Materia, CSIC, Madrid (Spain); Balabanski, D. L. [INRNE-BAS, Sofia (Bulgaria); Blazhev, A. [IKP, Cologne (Germany); Clement, E.; Grevy, S.; Stodel, C.; Thomas, J. C. [GANIL, Caen (France); Danchev, M. [University of Sofia (Bulgaria); Daugas, J. M. [CEA, DAM, DIF, 91297 Arpajon cedex (France); Hass, M.; Kumar, V. [The Weizmann Institute, Rehovot (Israel); Leske, J.; Pietralla, N. [TU Darmstadt, Darmstadt (Germany)
A Darcy law for the drift velocity in a two-phase flow model
This work deals with the design and numerical approximation of an Eulerian mixture model for the simulation of two-phase dispersed flows. In contrast to the more classical two-fluid or Drift-flux models, the influence of the velocity disequilibrium is ... Keywords: Bubbly flows, Chapman-Enskog expansion, Darcy law, Drift-flux, Riemann solver, Two-phase flows
H. Guillard; F. Duval
ARDB-158 R. Siemann November 6, 1997 Group Velocity Dispersion in Hamamatsu Streak Camera
1 1 2( ) ( ) The large chromatic time delay indicates that there is a large fraction of flint glass in the objective which is a proprietary design manufactured by Nikon. Using the data for SF4 (Flint glass) from and group velocities for borosicilate (BK7) and flint (SF4) glasses (Staerk et al) #12;2 Duncan et al
Effect of wave boundary layer on sea-to-air dimethylsulfide transfer velocity during typhoon passage
: Dimethylsulfide; Sea-to-air gas transfer velocity; Wave boundary layer; Tropical cyclone; Drag coefficient in order to accurately calculate aerosol radiative forcing. The sea-to-air DMS flux depends on airside coefficient CD and roughness length z0 has been investigated over small areas of the sea or in wave tanks
Chu, Peter C.
On Energy Flux and Group Velocity of Waves in Baroclinic Flows
A modified energy flux is defined by adding a nondivergent term that involves ? to the traditional energy flux. The resultant flux, when normalized by the total eddy energy, is exactly equal to the group velocity of Rossby waves on a ? plane with ...
Edmund K. M. Chang; Isidoro Orlanski
Mean Vertical Velocities Measured by Indian MST Radar and Comparison with Indirectly Computed Values
Mean vertical velocities and their variations observed with Indian mesosphereñstratosphereñtroposphere (MST) radar located at Gadanki (13.5∞N, 79.2∞E), a tropical station in India, are presented. In this study, a comparison has been made between ...
V. V. M. Jagannadha Rao; D. Narayana Rao; M. Venkat Ratnam; K. Mohan; S. Vijaya Bhaskar Rao
Understanding the gas content of high-redshift halos is crucial for studying the formation of the first generation of galaxies and reionization. Recently, Tseliakhovich and Hirata showed that the relative 'stream' velocity between the dark matter and baryons at the time of recombination-formally a second-order effect, but an unusually large one-can influence the later structure formation history of the universe. We quantify the effect of the stream velocity on the so-called characteristic mass-the minimum mass of a dark matter halo capable of retaining most of its baryons throughout its formation epoch-using three different high-resolution sets of cosmological simulations (with separate transfer functions for baryons and dark matter) that vary in box size, particle number, and the value of the relative velocity between the dark matter and baryons. In order to understand this effect theoretically, we generalize the linear theory filtering mass to properly account for the difference between the dark matter and baryonic density fluctuation evolution induced by the stream velocity. We show that the new filtering mass provides an accurate estimate for the characteristic mass, while other theoretical ansatzes for the characteristic mass are substantially less precise.
Naoz, Smadar [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)] [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Yoshida, Naoki [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan)] [Department of Physics, University of Tokyo, Tokyo 113-0033 (Japan); Gnedin, Nickolay Y., E-mail: firstname.lastname@example.com [Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States)
Velocities of deep water reservoir sands De-hua Han, University of Houston
and shale, which is not focus for this study. Sorting HP Shale ShallowDeep Sorting HP Shale Sorting HP Shale sands. Grain density is 2.65 gm/cc, typical for clean sands. Measured gas permeability ranged from 100 have revealed gradual effect of clay content on porosity and velocity of shaly sands and sandy shales
Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia)
Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia) U. Wegler,1 of the edifice of Merapi volcano (Java, Indonesia) before its eruption in 1998 by analyzing multiply scattered eruption of Merapi volcano (Indonesia), Geophys. Res. Lett., 33, L09303, doi:10.1029/2006GL025928. 1
Snieder, Roel
Bathymetry estimation using drifter-based velocity measurements on the Kootenai River, ID, USA
Velocity measurements from drifter GPS records are used in an ensemble-based data assimilation technique to extract the river bathymetry. The method is tested on a deep meandering reach and a shallow braided reach of the Kootenai River in Idaho, ...
Kyle C. Landon; Greg W. Wilson; H. Tuba ÷zkan-Haller; Jamie H. MacMahan
The Rossiter-McLaughlin effect and analytic radial velocity curves for transiting extrasolar planetary systems
A transiting extrasolar planet sequentially blocks off the light coming from the different parts of the disk of the host star in a time dependent manner. Due to the spin of the star, this produces an asymmetric distortion in the line profiles of the stellar spectrum, leading to an apparent anomaly of the radial velocity curves, known as the Rossiter - McLaughlin effect. Here, we derive approximate but accurate analytic formulae for the anomaly of radial velocity curves taking account of the stellar limb darkening. The formulae are particularly useful in extracting information of the projected angle between the planetary orbit axis and the stellar spin axis, \\lambda, and the projected stellar spin velocity, V sin I_s. We create mock samples for the radial curves for the transiting extrasolar system HD209458, and demonstrate that constraints on the spin parameters (V sin I_s, \\lambda) may be significantly improved by combining our analytic template formulae and the precision velocity curves from high-resolution spectroscopic observations with 8-10 m class telescopes. Thus future observational exploration of transiting systems using the Rossiter - McLaughlin effect is one of the most important probes to better understanding of the origin of extrasolar planetary systems, especially the origin of their angular momentum.
Yasuhiro Ohta; Atsushi Taruya; Yasushi Suto
Average crack front velocity during subcritical fracture propagation in a heterogeneous medium
the free energy, and thus the energy barrier, via numerous competing mech- anisms like stress corrosion speed of crack growth with increasing G; a weak stress- sensitive regime II follows where transportAverage crack front velocity during subcritical fracture propagation in a heterogeneous medium
Ampuero, Jean Paul
Cumulonimbus Vertical Velocity Events in GATE. Part II: Synthesis and Model Core Structure
The properties of convective drafts and cores are presented in Part I. By our definition a convective updraft must have a positive vertical velocity for 0.5 km, and exceed 0.5 m s?1 for 1 s; a convective updraft core must exceed 1 m s?1 for 0.5 ...
E. J. Zipser; M. A. LeMone
On physical interpretation of two dimensional time-correlations regarding time delay velocities and eddy shaping
Time delay estimation (TDE) techniques are frequently used to estimate the flow velocity from fluctuating measurements. Tilted structures carried by the flow lead to misinterpretation of the time delays in terms of velocity direction and amplitude. It affects TDE measurements from probes, and is also intrinsically important for beam emission spectroscopy and gas puff imaging measurements. Local eddy shapes estimated from 2D fluctuating field are necessary to gain a more accurate flow estimate from TDE, as illustrated by Langmuir probe array measurements. A least square regression approach is proposed to estimate both flow field and shaping parameters. The technique is applied to a test case built from numerical simulation of interchange fluctuations. The local eddy shape does not only provide corrections for the velocity field but also quantitative information about the statistical interaction mechanisms between local eddies and E Multiplication-Sign B flow shear. The technique is then tested on gaz puff imaging data collected at the edge of EAST tokamak plasmas. It is shown that poloidal asymmetries of the fluctuation fields-velocity and eddy shape-are consistent at least qualitatively with a ballooning type of turbulence immersed in a radially sheared equilibrium flow.
Fedorczak, N. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Manz, P. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); Max-Planck-Institut feur Plasmaphysik, Association Euratom-IPP, 85748Garching (Germany); Thakur, S. C.; Xu, M.; Tynan, G. R. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); Xu, G. S.; Liu, S. C. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)
A California Statewide Three-Dimensional Seismic Velocity Model from Both Absolute and Differential Times
A California Statewide Three-Dimensional Seismic Velocity Model from Both Absolute and Differential of the California crust and uppermost mantle using a regional-scale double-difference tomography algorithm. We begin using S picks from both the Southern California Seismic Network and USArray, assuming a starting model
Shearer, Peter
The Mean and Near-Inertial Velocity Fields in a Warm-Core Ring
Velocity and temperature profiles collected in warm-core ring 82-I in January 1983 are used to describe the mean and fluctuating fields of the ring. The ring was relatively small, containing no Sargasso See water. Its signature vanished below 600 ...
Eric Kunze
Estimating fracture parameters from p-wave velocity profiles about a geothermal well
The feasibility of locating fracture zones and estimating their crack parameters was examined using an areal well shoot method centered on Utah State Geothermal Well 9-1, Beaver County, Utah. High-resolution travel time measurements were made between a borehole sensor and an array of shot stations distributed radially and azimuthally about the well. Directional velocity behavior in the vicinity of the well was investigated by comparing velocity logs derived from the travel time data. Three fracture zones were identified form the velocity data, corroborating fracture indicators seen in other geophysical logs conducted in Well 9-1. Crack densities and average crack aspect ratios for these fracture zones were estimated using a self-consistent velocity theory (O'Connell and Budiansy 1974). Probable trends of these fracture zones were established from a combination of the data from the more distant shot stations and the results of a gravity survey. The results of this study indicate that the areal well shoot is a potentially powerful tool for the reconnaisance of fracture-controlled fluid and gas reservoirs. Improvements in methodology and hardware could transform it into an operationally viable survey method.
Jenkinson, J.T.; Henyey, T.L.; Sammis, C.G.; Leary, P.C.; McRaney, J.K.
Rapid Cardiovascular Flow Quantitation Using Slice-Selective Spiral Fourier Velocity Encoding J. L. Carvalho1
by gridding and inverse Fourier transform, converting the acquired data S(kx,ky,kv,t) to S(x,y,kv,t). A region. Carvalho1 , K. S. Nayak1 1 Department of Electrical Engineering, University of Southern California, Los. The use of FVE instead of PC makes it possible to resolve the full velocity distribution within each voxel
Southern California, University of
On the Group-Velocity Property for Wave-Activity Conservation Laws
The density and the flux of wave-activity conservation laws are generally required to satisfy the group-velocity property: under the WKB approximation (i.e., for nearly monochromatic small-amplitude waves in a slowly varying medium), the flux ...
J. Vanneste; T. G. Shepherd
An Improved Approach to Calculating Terminal Velocities of Plate-like Crystals and Graupel
Measurements of 461 planar crows and 312 graupel reported by Kajikawa have been used to develop equations for calculating the terminal velocity and mass of lump and conical graupel and of planar crystals of a variety of shapes and degrees of ...
Andrew J. Heymsfield; Masahiro Kajikawa
Property:Current Velocity Range(m/s) | Open Energy Information
Velocity Range(m/s) Velocity Range(m/s) Jump to: navigation, search Property Name Current Velocity Range(m/s) Property Type String Pages using the property "Current Velocity Range(m/s)" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + 0.0 + 10-ft Wave Flume Facility + 0.0 + 11-ft Wave Flume Facility + 0.0 + 2 2-ft Flume Facility + 0.0 + 3 3-ft Wave Flume Facility + 0.0 + 5 5-ft Wave Flume Facility + 0.0 + 6 6-ft Wave Flume Facility + 0.0 + A Alden Large Flume + 3.2 + Alden Small Flume + 0.0 + Alden Wave Basin + 0.0 + B Breakwater Research Facility + 0.0 + C Carderock Maneuvering & Seakeeping Basin + 0.0 + Carderock Tow Tank 2 + 0.0 + Carderock Tow Tank 3 + 0.0 + Chase Tow Tank + 0.0 + Coastal Harbors Modeling Facility + 0.0 +
A test of Einstein's theory of gravitation: Velocity distribution of low-energy particles in a spherically symmetric gravitational field
We propose a new test of Einstein's theory of gravitation. It concerns the velocity distribution of low-energy particles in a spherically symmetric gravitational field.
Hurricane Earl
Historical/Selected Significant Energy Disruptions > Hurricane Earl Historical/Selected Significant Energy Disruptions > Hurricane Earl Hurricane Earl Released: September 3, 2010 2:00 p.m. EDT Map Sources: Infrastructure-Energy Information Administration (GasTran System), Ventyx (Energy Velocity); Hurricane path with 67% likelihood cone-National Oceanic and Atmospheric Administration (NOAA) Uncheck or check an item to hide or show it in the map. Electric Power Plants (>=100 MW) Coal Hydroelectric Natural Gas Nuclear Petroleum Wood Wind Other Electricity Transmission Lines (>=345kV) LNG terminals Natural Gas Market Centers (Hubs) Natural Gas Processing Plants Natural Gas Interstate, Intrastate, and Gathering Pipelines Oil Import Site & Oil Seaports Petroleum Refineries Heating Oil Reserve Site Additional Resources: Gulf of Mexico Fact Sheet
Suites Catering Menu --Fall 2012 ScholarshipSuites
and Monterey Jack cheeses garnished with sour cream and green onions served with tortilla chips Pancetta Dip Traditional hummus made from organic garbanzo beans garnished with kalamata olives, peppadew peppers and extra Tray $40 (Local and Imported) Garnished with berries and grapes, served with assorted crackers Shrimp
Peterson, Blake R.
Suites Catering Menu --Fall 2011 ScholarshipSuites
, horseradish sauce, stone ground mustard, and vegetable garnish Nacho Bar $50 Start with seasoned ground beef and ranch dip Assorted Cheese Tray $40 (Local and Imported) Garnished with berries and grapes, served garnish St. Louis Style Ribs $25 Fall-off-the-bone tender and slathered with carmelized BBQ sauce, a slab
We present an interferometric kinematic study of morphologically complex protostellar envelopes based on observations of the dense gas tracers N{sub 2}H{sup +} and NH{sub 3}. The strong asymmetric nature of most envelopes in our sample leads us to question the common interpretation of velocity gradients as rotation, given the possibility of projection effects in the observed velocities. Several 'idealized' sources with well-ordered velocity fields and envelope structures are now analyzed in more detail. We compare the interferometric data to position-velocity (PV) diagrams of kinematic models for spherical rotating collapse and filamentary rotating collapse. For this purpose, we developed a filamentary parameterization of the rotating collapse model to explore the effects of geometric projection on the observed velocity structures. We find that most envelopes in our sample have PV structures that can be reproduced by an infalling filamentary envelope projected at different angles within the plane of the sky. The infalling filament produces velocity shifts across the envelope that can mimic rotation, especially when viewed at single-dish resolutions and the axisymmetric rotating collapse model does not uniquely describe any data set. Furthermore, if the velocities are assumed to reflect rotation, then the inferred centrifugal radii are quite large in most cases, indicating significant fragmentation potential or more likely another component to the line-center velocity. We conclude that ordered velocity gradients cannot be interpreted as rotation alone when envelopes are non-axisymmetric and that projected infall velocities likely dominate the velocity field on scales larger than 1000 AU.
Tobin, John J.; Hartmann, Lee; Bergin, Edwin [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Chiang, Hsin-Fang; Looney, Leslie W. [Department of Astronomy, University of Illinois at Champaign/Urbana, Urbana, IL 61801 (United States); Chandler, Claire J. [National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States); Maret, Sebastien [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble F-38041 (France); Heitsch, Fabian, E-mail: firstname.lastname@example.com [Department of Astronomy, University of North Carolina, Chapel Hill, NC (United States)
A summary of recent refinements to the WAKE dispersion model, a component of the HGSYSTEM/UF{sub 6} model suite
The original WAKE dispersion model a component of the HGSYSTEM/UF{sub 6} model suite, is based on Shell Research Ltd.`s HGSYSTEM Version 3.0 and was developed by the US Department of Energy for use in estimating downwind dispersion of materials due to accidental releases from gaseous diffusion plant (GDP) process buildings. The model is applicable to scenarios involving both ground-level and elevated releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant. Over the 2-year period since its creation, the WAKE model has been used to perform consequence analyses for Safety Analysis Reports (SARs) associated with gaseous diffusion plants in Portsmouth (PORTS), Paducah (PGDP), and Oak Ridge. These applications have identified the need for additional model capabilities (such as the treatment of complex terrain and time-variant releases) not present in the original utilities which, in turn, has resulted in numerous modifications to these codes as well as the development of additional, stand-alone postprocessing utilities. Consequently, application of the model has become increasingly complex as the number of executable, input, and output files associated with a single model run has steadily grown. In response to these problems, a streamlined version of the WAKE model has been developed which integrates all calculations that are currently performed by the existing WAKE, and the various post-processing utilities. This report summarizes the efforts involved in developing this revised version of the WAKE model.
Yambert, M.W.; Lombardi, D.A.; Goode, W.D. Jr.; Bloom, S.G.
 who _______ negative colonoscopy 1st degree relative ______ Occult GI bleeding with ______ Abnormal, x-ray or CT ______ Occult GI bleeding (attach report) ______ Hematochezia ______ Nausea and
Viola, Ronald
GENII. Environmental Radiation Dosimetry Suite
GENII was developed to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) into the environmental pathway analysis models used at Hanford. GENII is a coupled system of seven programs and the associated data libraries that comprise the Hanford Dosimetry System (Generation II) to estimate potential radiation doses to individuals or populations from both routine and accidental releases of radionuclides to air or water and residual contamination from spills or decontamination operations. The GENII system includes interactive menu-driven programs to assist the user with scenario generation and data input,internal and external dose factor generators, and environmental dosimetry programs. The programs analyze environmental contamination resulting from both far-field and near-field scenarios. A far-field scenario focuses outward from a source, while a near-field scenario focuses in toward a receptor. GENII can calculate annual dose, committed dose, and accumulated dose from acute and chronic releases from ground or elevated sources to air or water and from initial contamination of soil or surfaces and can evaluate exposure pathways including direct exposure via water, soil, air, inhalation pathways, and ingestion pathways. In addition, GENII can perform 10,000 years migration analyses and can be used for retrospective calculations of potential radiation doses resulting from routine emissions and for prospective dose calculations for purposes such as siting facilities, environmental impact statements, and safety analysis reports.
Napier, B.A. [Pacific Northwest Lab., Richland, WA, (United States)
Direct Measurements of Vertical-Velocity Power Spectra with the Sousy-VHF-Radar Wind Profiler System
We present power spectra of vertical velocities measured with the SOUSY-VHF-Radax wind profiler.over a 5-day period in October and November 1981. Most of the data consist of hourly vertical velocity profiles based on 12-rain averages, but, for ...
M. F. Larsen; J. Rutger; D. N. Holden
Experimental study of layer mixing, relative ionic escape velocity, and electron temperature gradients in spherical multilayered targets by XUV spectroscopy
This past year we have undertaken experiments at the University of Rochester's Laboratory for Laser Energetics investigating layer mixing and expansion velocities of spherical targets uniformly irradiated by high intensity laser light. We performed high resolution spectroscopic measurements of spherical plasmas, produced using the Omega laser, and have observed enhanced broadening of XUV emission lines due to the expansion velocities.
Griem, H.R.
IEEE SENSORS JOURNAL, VOL. 8, NO. 7, JULY 2008 1099 Fiber-Optic Sensor for Web Velocity Measurement
of light from the web surface (with no physical contact), the output of the fiber-optic sensorIEEE SENSORS JOURNAL, VOL. 8, NO. 7, JULY 2008 1099 Fiber-Optic Sensor for Web Velocity Measurement Abstract--The design and development of a new fiber-optic sensor for measuring the velocity of a continuous
Pagilla, Prabhakar R.
Evaluation of the Maximum Cross-Correlation Method of Estimating Sea Surface Velocities from Sequential Satellite Images
We evaluate the method of estimating sea surface velocities from sequences of AVHRR and CZCS images using the maximum cross-correlation (MCC) technique. A set of synthetic images is created by advecting an AVHRR-SST field with a QG model velocity ...
Robin Tokmakian; P. Ted Strub; Julie McClean-Padman
Modelling Solar Oscillation Power Spectra: II. Parametric Model of Spectral Lines Observed in Doppler Velocity Measurements
We describe a global parametric model for the observed power spectra of solar oscillations of intermediate and low degree. A physically motivated parameterization is used as a substitute for a direct description of mode excitation and damping as these mechanisms remain poorly understood. The model is targeted at the accurate fitting of power spectra coming from Doppler velocity measurements and uses an adaptive response function that accounts for both the vertical and horizontal components of the velocity field on the solar surface and for possible instrumental and observational distortions. The model is continuous in frequency, can easily be adapted to intensity measurements and extends naturally to the analysis of high-frequency pseudo modes (interference peaks at frequencies above the atmospheric acoustic cutoff).
Vorontsov, Sergei V
Tracking granules on the Sun's surface and reconstructing horizontal velocity fields: I. the CST algorithm
Determination of horizontal velocity fields on the solar surface is crucial for understanding the dynamics of structures like mesogranulation or supergranulation or simply the distribution of magnetic fields. We pursue here the development of a method called CST for coherent structure tracking, which determines the horizontal motion of granules in the field of view. We first devise a generalization of Strous method for the segmentation of images and show that when segmentation follows the shape of granules more closely, granule tracking is less effective for large granules because of increased sensitivity to granule fragmentation. We then introduce the multi-resolution analysis on the velocity field, based on Daubechies wavelets, which provides a view of this field on different scales. An algorithm for computing the field derivatives, like the horizontal divergence and the vertical vorticity, is also devised. The effects from the lack of data or from terrestrial atmospheric distortion of the images are also briefly discussed.
M. Rieutord; T. Roudier; S. Roques; C. Ducottet
Extremely low surface recombination velocities in black silicon passivated by atomic layer deposition
We investigate the optical and opto-electronic properties of black silicon (b-Si) nanostructures passivated with Al{sub 2}O{sub 3}. The b-Si nanostructures significantly improve the absorption of silicon due to superior anti-reflection and light trapping properties. By coating the b-Si nanostructures with a conformal layer of Al{sub 2}O{sub 3} by atomic layer deposition, the surface recombination velocity can be effectively reduced. We show that control of plasma-induced subsurface damage is equally important to achieve low interface recombination. Surface recombination velocities of S{sub eff}<13 cm/s have been measured for an optimized structure which, like the polished reference, exhibits lifetimes in the millisecond range.
Otto, Martin [Martin-Luther-University Halle-Wittenberg, mu MD Group-Institute of Physics, Heinrich-Damerow-Strasse 4, 06120 Halle (Germany); Kroll, Matthias; Kaesebier, Thomas; Tuennermann, Andreas [Friedrich-Schiller-Universitaet Jena, Institute of Applied Physics, Max-Wien-Platz 1, 07743 Jena (Germany); Salzer, Roland [Fraunhofer Institute for Mechanics of Materials Halle, Walter-Huelse-Str. 1, 06120 Halle (Germany); Wehrspohn, Ralf B. [Martin-Luther-University Halle-Wittenberg, mu MD Group-Institute of Physics, Heinrich-Damerow-Strasse 4, 06120 Halle (Germany); Fraunhofer Institute for Mechanics of Materials Halle, Walter-Huelse-Str. 1, 06120 Halle (Germany)
On mass and velocity distributions in members of star clusters An analytical approach
Dynamical evolution of stellar mass distribution in star clusters is analysed by considering simultaneously the effects of dynamical friction, stochastic heating and the gravitational potential due to mass distribution in the clusters. A simple expression is suggested for the dynamical friction which adequately describes it in both high and low velocity ranges and the effect of mass distribution in the cluster on the dynamics of a test mass can be described by an anharmonic potential. With the help of energy considerations we describe the dispersions in position and in velocity for stars of different masses showing how the slowing down and mass segregation of stars evolve in the cluster. Results are presented with the parameters for the star clusters of our Galaxy.
Chatterjee, S; Sagar, R; Kumar, Brijesh; Sagar, Ram
On mass and velocity distributions in members of star clusters : An analytical approach
S. Chatterjee; Brijesh Kumar; Ram Sagar
Effect of the Darrieus-Landau instability on turbulent flame velocity
Propagation of turbulent premixed flames influenced by the intrinsic hydrodynamic flame instability (the Darrieus-Landau instability) is considered in a two-dimensional case using the model nonlinear equation proposed recently. The nonlinear equation takes into account both influence of external turbulence and intrinsic properties of a flame front, such as small but finite flame thickness and realistically large density variations across the flame front. Dependence of the flame velocity on the turbulent length scale, on the turbulent intensity and on the density variations is investigated in the case of weak non-linearity and weak external turbulence. It is shown that the Darrieus-Landau instability influences the flamelet velocity considerably. The obtained results are in agreement with experimental data on turbulent burning of moderate values of the Reynolds number.
Maxim Zaytsev; Vitaliy Bychkov
Velocity map imaging of HBr photodissociation in large rare gas clusters
We have implemented the velocity map imaging technique to study clustering in the pulsed supersonic expansions of hydrogen bromide in helium, argon, and xenon. The expansions are characterized by direct imaging of the beam velocity distributions. We have investigated the cluster generation by means of UV photodissociation and photoionization of HBr molecules. Two distinct features appear in the hydrogen atom photofragment images in the clustering regime: (i) photofragments with near zero kinetic energies and (ii) ''hot'' photofragments originating from vibrationally excited HBr molecules. The origin of both features is attributed to the fragment caging by the cluster. We discuss the nature of the formed clusters based on the change of the photofragment images with the expansion parameters and on the photoionization mass spectra and conclude that single HBr molecule encompassed with rare gas ''snowball'' is consistent with the experimental observations.
Fedor, J.; Kocisek, J.; Poterya, V.; Votava, O.; Pysanenko, A.; Farnik, M. [J. Heyrovsky Institute of Physical Chemistry v.v.i., Academy of Sciences of the Czech Republic, Dolejskova 3, 18223 Prague (Czech Republic); Lipciuc, M. L. [Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA (United Kingdom); Kitsopoulos, T. N. [Department of Chemistry, University of Crete, Heraklion (Greece) and Institute of Electronic Structure and Lasers, Foundation for Research and Technology, Hellas, P.O. Box 1527, 71110 Heraklion (Greece)
On the X-ray low- and high-velocity outflows in AGNs
An exploration of the relationship between bolometric luminosity and outflow velocity, for two classes of X-ray outflows in a large sample of active galactic nuclei has been performed. We find that line radiation pressure could be one physical mechanism that might accelerate the gas we observe in warm absorber, v~100-1000 km/s, and on comparable but less stringent grounds the ultra-fast outflows (UFOs), v~0.03-0.3c. If comparable with the escape velocity of the system; the first is naturally located at distances of the dusty torus, ~ 1 pc, and the second at sub-parsec scales, ~ 0.01 pc, in accordance with large set of observational evidence existing in the literature. The presentation of this relationship might give us key clues for our understanding of the different physical mechanisms acting in the center of galaxies, the feedback process and its impact on the evolution of the host galaxy.
Ramirez, J M
Imaging earth's interior: Tomographic inversions for mantle P-wave velocity structure
A formalism is developed for the tomographic inversion of seismic travel time residuals. The travel time equations are solved both simultaneously, for velocity model terms and corrections to the source locations, and progressively, for each set of terms in succession. The methods differ primarily in their treatment of source mislocation terms. Additionally, the system of equations is solved directly, neglecting source terms. The efficacy of the algorithms is explored with synthetic data as we perform simulations of the general procedure used to produce tomographic images of Earth's mantle from global earthquake data. The patterns of seismic heterogeneity in the mantle that would be returned reliably by a tomographic inversion are investigated. We construct synthetic data sets based on real ray sampling of the mantle by introducing spherical harmonic patterns of velocity heterogeneity and perform inversions of the synthetic data.
Pulliam, R.J.
Magnetic Resonance Flow Velocity and Temperature Mapping of a Shape Memory Polymer Foam Device
Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment. A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment. Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired. Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated.
Small IV, W; Gjersing, E; Herberg, J L; Wilson, T S; Maitland, D J
Electrical method and apparatus for impelling the extruded ejection of high-velocity material jets
A method and apparatus (10, 40) for producing high-velocity material jets provided. An electric current pulse generator (14, 42) is attached to an end of a coaxial two-conductor transmission line (16, 44) having an outer cylindrical conductor (18), an inner cylindrical conductor (20), and a solid plastic or ceramic insulator (21) therebetween. A coxial, thin-walled metal structure (22, 30) is conductively joined to the two conductors (18, 20) of the transmission line (16, 44). An electrical current pulse applies magnetic pressure to and possibly explosively vaporizes metal structure (22), thereby collapsing it and impelling the extruded ejection of a high-velocity material jet therefrom. The jet is comprised of the metal of the structure (22), together with the material that comprises any covering layers (32, 34) disposed on the structure. An electric current pulse generator of the explosively driven magnetic flux compression type or variety (42) may be advantageously used in the practice of this invention.
Weingart, Richard C. (Livermore, CA)
WHAM Observations of H-alpha from High-Velocity Clouds Are They Galactic or Extragalactic?
It has been suggested that high velocity clouds may be distributed throughout the Local Group and are therefore not in general associated with the Milky Way galaxy. With the aim of testing this hypothesis, we have made observations in the H-alpha line of high velocity clouds selected as the most likely candidates for being at larger than average distances. We have found H-alpha emission from 4 out of 5 of the observed clouds, suggesting that the clouds under study are being illuminated by a Lyman continuum flux greater than that of the metagalactic ionizing radiation. Therefore, it appears likely that these clouds are in the Galactic halo and not distributed throughout the Local Group.
Tufte, S L; Madsen, G J; Haffner, L M; Reynolds, R J
WHAM Observations of H-alpha from High-Velocity Clouds: Are They Galactic or Extragalactic?
S. L. Tufte; J. D. Wilson; G. J. Madsen; L. M. Haffner; R. J. Reynolds
Group velocity and pulse lengthening of mismatched laser pulses in plasma channels
Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be independent of propagation distance andsignificantly less than that of a matched pulse. Laser pulse lengthening of a mismatched pulse owing to laser mode slippage isexamined and found to dominate over that due to dispersive pulse spreading for sufficiently long pulses. Analytic results are shown tobe in excellent agreement with numerical solutions of the full Maxwell equations coupled to the plasma response. Implications for plasmachannel diagnostics are discussed.
Schroeder, Carl; Benedetti, Carlo; Esarey, Eric; van Tilborg, Jeroen; Leemans, Wim
Mapping Metal-Enriched High Velocity Clouds to Very Low HI Column Densities
Our galaxy is the nearest known quasar absorption line system, and it uniquely provides us with an opportunity to probe multiple lines of sight through the same galaxy. This is essential for our interpretations of the complex kinematic profiles seen in the MgII absorption due to lines of sight through intermediate redshift galaxies. The Milky Way halo has never been probed for high velocity clouds below the 21-cm detection threshold of N(HI)~10^18 cm-2. Through a survey of MgII absorption looking toward the brightest AGNs and quasars, it will be possible to reach down a few orders of magnitude in HI column density. The analogs to the high velocity components of the MgII absorption profiles due to intermediate redshift galaxies should be seen. We describe a program we are undertaking, and present some preliminary findings.
Chris Churchill; Jane Charlton; Joe Masiero
A method and apparatus for producing high-velocity material jets is provided. An electric current pulse generator is attached to an end of a coaxial two-conductor transmission line having an outer cylindrical conductor, an inner cylindrical conductor, and a solid plastic or ceramic insulator there between. A coaxial, thin-walled metal structure is conductively joined to the two conductors of the transmission line. An electrical current pulse applies magnetic pressure to and possibly explosively vaporizes metal structure, thereby collapsing it and impelling the extruded ejection of a high-velocity material jet therefrom. The jet is comprised of the metal of the structure, together with the material that comprises any covering layers disposed on the structure. An electric current pulse generator of the explosively driven magnetic flux compression type or variety may be advantageously used in the practice of this invention. 3 figs.
Weingart, R.C.
Technical Challenges in Low-velocity SRF Development ATLAS 25th Anniversary Celebration
Challenges in Low-velocity SRF Development Challenges in Low-velocity SRF Development ATLAS 25th Anniversary Celebration October 22-23, 2010 Physics Division, Argonne National Laboratory Building 203, Auditorium Speaker: Mike Kelly ATLAS Energy Upgrade: Commissioned June 2009 14.5 MV in 5 meters using 7 SC Quarter-wave Cavities Superconductivity 1911 - superconductivity discovered by Kamerlingh Onnes in a sample of Hg at 4 Kelvin 1950's: - Ginsburg-Landau theory developed - 1957 - Bardeen, Cooper, and Schrieffer theory First applications such as SC magnets 1964 - SC resonators developed for accelerator applications at Stanford Leiden, ca. 1910 4 Outline Materials from: Ken Shepard, Joel Fuerst I. Some superconductivity background II. Progress in RF superconductivity
Symmetry properties of the large-deviation function of the velocity of a self-propelled polar particle
A geometrically polar granular rod confined in 2-D geometry, subjected to a sinusoidal vertical oscillation, undergoes noisy self-propulsion in a direction determined by its polarity. When surrounded by a medium of crystalline spherical beads, it displays substantial negative fluctuations in its velocity. We find that the large deviation function (LDF) for the normalized velocity is strongly non-Gaussian with a kink at zero velocity, and that the antisymmetric part of the LDF is linear, resembling the fluctuation relation known for entropy production, even when the velocity distribution is clearly non-Gaussian. We extract an analogue of the phase space contraction rate and find that it compares well with an independent estimate based on the persistence of forward and reverse velocities.
Nitin Kumar; Sriram Ramaswamy; A. K. Sood
The southwest edge of Eurasia is a tectonically and structurally complex region that includes the Caspian and Black Sea basins, the Caucasus Mountains, and the high plateaus south of the Caucasus. Using data from 25 broadband stations located in the region, new estimates of crustal and upper mantle thickness, velocity structure, and attenuation are being developed. Receiver functions have been determined for all stations. Depth to Moho is estimated using slant stacking of the receiver functions, forward modeling, and inversion. Moho depths along the Caspian and in the Kura Depression are in general poorly constrained using only receiver functions due to thick sedimentary basin sediments. The best fitting models suggest a low velocity upper crust with Moho depths ranging from 30 to 40 km. Crustal thicknesses increase in the Greater Caucasus with Moho depths of 40 to 50 km. Pronounced variations with azimuth of source are observed indicating 3D structural complexity and upper crustal velocities are higher than in the Kura Depression to the south. In the Lesser Caucasus, south and west of the Kura Depression, the crust is thicker (40 to 50 km) and upper crustal velocities are higher. Work is underway to refine these models with the event based surface wave dispersion and ambient noise correlation measurements from continuous data. Regional phase (Lg and Pg) attenuation models as well as blockage maps for Pn and Sn are being developed. Two methods are used to estimate Q: the two-station method to estimate inter-station Q and the reversed, two-station, two event method. The results are then inverted to create Lg and Pg Q maps. Initial results suggest substantial variations in both Pg and Lg Q in the region. A zone of higher Pg Q extends west from the Caspian between the Lesser and Greater Caucasus and a narrow area of higher Lg Q is observed.
Mellors, R; Gok, R; Pasyanos, M; Skobeltsyn, G; Teoman, U; Godoladze, T; Sandvol, E
Mechanical joining with self piercing solid-rivets at elevated tool velocities
In the present paper the influence of a higher setting velocity in the joining process of self piercing solid-rivets is shown. In the conventional process tool velocities well below 1 m/s are common. The present research results show the potential of increasing them in the range of about 5 m/s. The results are especially relevant for joining high-strength steels. These steel sheets often cause problems in the process of riveting mixed materials, e. g. aluminium-steel compound. The high strength of the steel sometimes leads to undesirable material flow in the joining process or unwanted burr development. These effects, which are described in detail in the article, can be reduced significantly for the investigated cases by the use of higher tool velocities. Using a high speed camera and a load cell, a test setup based on a drop tower was realized. It was used to time the force signals and the motion profile of the high speed riveting process. The results of the force analysis show an oscillating force progression. Within a numerical research the principal effects influencing the results of the riveting process can be shown. It was found that the pulse-like force transmission between riveting machine and punch, results in various vibrations especially of long and thin tool parts. Hence the rivet penetrates the sheet metal with non-uniform velocities. As a result the early indentation of die into the lower sheet metal at the beginning of the process is reduced, so that the final process step provides a sufficient material flow into the circular rivet groove. A strain-rate dependent process model with elastic tool properties and consideration of inertia effects is presented.
Neugebauer, R.; Jesche, F.; Kraus, C.; Hensel, S. [Fraunhofer Institute for Machine Tools and Forming Technology IWU, Reichenhainer Strasse 88, 09126 Chemnitz (Germany)
Water Velocity Measurement on an Extended-Length Submerged Bar Screen at John Day Dam
This report describes a study of water velocity around an extended-length submerged bar screen (ESBS) at John Day Dam. The study was conducted for the U.S. Army Corps of Engineers by AScI Corporation and MEVATEC Corporation in March of 2000. This report was prepared by Pacific Northwest National Laboratory. ESBS are being studied as one method for diverting juvenile migrating fish from the dam's turbine intakes into the gate well and through the juvenile fish bypass channels.
Weiland, Mark A
Mˆbius Transformation and Einsten Velocity Addition in the Hyperbolic Geometry of Bolyai and Lobachevsky
In this chapter, dedicated to the 60th Anniversary of Themistocles M. Rassias, M\\"obius transformation and Einstein velocity addition meet in the hyperbolic geometry of Bolyai and Lobachevsky. It turns out that M\\"obius addition that is extracted from M\\"obius transformation of the complex disc and Einstein addition from his special theory of relativity are isomorphic in the sense of gyrovector spaces.
Abraham A. Ungar
The effect of arc velocity on cold electrode erosion Alexei M. Essiptchouk,a)
of the radial redistribution of the gas due to centrifugal force in the vortex. Therefore the cold- est gas in air, for magnetic induction values B in the range of 0.0050.386 T, axial air gas velocity of 7.65 ms displacement are used to diminish the erosion of the electrode: gas dynamic, i.e., application of vortex flow
Marotta, Aruy
The analyzer forms part of the Materials Testing Reactor Velocity Selector Experiment which measures energy change versus scattering angle for subthermal neutrons scattered off a target. It is similar to other time-of- flight lyzers except for certain unique features. Among these features are input and output buffer matrices, a randomly pulsed crystal time-base generator, and a direct 48transistor drive circuit for the 4096 channel magnetic core matrix. (auth)
Petree, F.L.
Radial Velocity Jitter in Stars from the California and Carnegie Planet Search at Keck Observatory
I present an empirical model for predicting a star's radial velocity jitter from its B-V color, activity level, and absolute magnitude. This model is based on observations of 450 well- observed stars from Keck Observatory for the California and Carnegie Planet Search Program. The model includes noise from both astrophysical sources and systematic errors, and describes jitter as generally increasing with a star's activity and height above the main sequence.
J. T. Wright
Generalization of Child-Langmuir Law for Non-Zero Injection Velocities in a Planar Diode
The Child-Langmuir law relates the voltage applied across a planar diode to the saturation value J_CL of current density that can be transmitted through it in case the injection velocity of electrons into the diode is zero. The Child-Langmuir current density J_CL is, at the same time, (i) the maximum current density that can be transmitted through a planar diode, (ii) the current density below which the flow is steady and unidirectional in the long time limit and (iii) the average transmitted current density for {\\em any} value of injected current density above J_CL. Existing generalizations of Child-Langmuir law to non-zero velocities of injection are based on the characteristics (i) and (ii) of J_CL. This paper generalizes the law to non-zero velocities of injection based on the characteristic (iii) by deriving an analytical expression for the saturation value of current density. The analytical expression for the saturation current density is found to be well supported by numerical computations. A reason behind preferring the saturation property of the Child-Langmuir current density as the basis for its generalization is the importance of that property in numerical simulations of high current diode devices.
R. R. Puri; Debabrata Biswas; Raghwendra Kumar
Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximately the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.
Hou Fengji; Hogg, David W. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Goodman, Jonathan; Weare, Jonathan [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012 (United States); Schwab, Christian, E-mail: firstname.lastname@example.com [Department of Astronomy, Yale University, 260 Whitney Avenue, New Haven, CT 06511 (United States)
The collisions of high-velocity clouds with the galactic halo
Spiral galaxies are surrounded by a widely distributed hot coronal gas and seem to be fed by infalling clouds of neutral hydrogen gas with low metallicity and high velocities. We numerically study plasma waves produced by the collisions of these high-velocity clouds (HVCs) with the hot halo gas and with the gaseous disk. In particular, we tackle two problems numerically: 1) collisions of HVCs with the galactic halo gas and 2) the dispersion relations to obtain the phase and group velocities of plasma waves from the equations of plasma motion as well as further important physical characteristics such as magnetic tension force, gas pressure, etc. The obtained results allow us to understand the nature of MHD waves produced during the collisions in galactic media and lead to the suggestion that these waves can heat the ambient halo gas. These calculations are aiming at leading to a better understanding of dynamics and interaction of HVCs with the galactic halo and of the importance of MHD waves as a heating proce...
Jelinek, Petr; 10.1016/j.cpc.2011.01.023
Positive/negative ion velocity mapping apparatus for electron-molecule reactions
In molecular dissociative ionization by electron collisions and dissociative electron attachment to molecule, the respective positively and negatively charged fragments are the important products. A compact ion velocity mapping apparatus is developed for the angular distribution measurements of the positive or negative fragments produced in the electron-molecule reactions. This apparatus consists of a pulsed electron gun, a set of ion velocity mapping optic lenses, a two-dimensional position detector including two pieces of micro-channel plates, and a phosphor screen, and a charge-coupled-device camera for data acquisition. The positive and negative ion detections can be simply realized by changing the voltage polarity of ion optics and detector. Velocity sliced images can be directly recorded using a narrow voltage pulse applied on the rear micro-channel plate. The efficient performance of this system is evaluated by measuring the angular distribution of O{sup -} from the electron attachments to NO at 7.3 and 8.3 eV and O{sup +} from the electron collision with CO at 40.0 eV.
Wu Bin; Xia Lei; Li Hongkai; Zeng Xianjin; Tian Shanxi [Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)
High-resolution seismic tomography of compressional wave velocity structure at Newberry Volcano, Oregon Cascade Range
Compressional wave velocity structure is determined for the upper crust beneath Newberry Volcano, central Oregon, using a high-resolution active-source seismic-tomography method. Newberry Volcano is a bimodal shield volcano east of the axis of the Cascade Range. It is associated both with the Cascade Range and with northwest migrating silicic volcanism in southeast Oregon. High-frequency (approx.7 Hz) crustal phases, nominally Pg and a midcrustal reflected phase, travel upward through a target volume beneath Newberry Volcano to a dense array of 120 seismographs. This arrangement is limited by station spacing to 1- to 2-km resolution in the upper 5 to 6 km of the crust beneath the volcano's summit caldera. The experiment tests the hypothesis that Cascade Range volcanoes are underlain only by small magma chambers. A small low-velocity anomaly delineated abosut 3 km below the summit caldera supports this hypothesis for Newberry Volcano and is interpreted as a possible magma chamber of a few to a few tens of km/sup 3/ in volume. A ring-shaped high-velocity anomaly nearer the surface coincides with the inner mapped ring fractures of the caldera. It also coincides with a circular gravity high, and we interpret it as largely subsolidus silicic cone sheets. The presence of this anomaly and of silicic vents along the ring fractures suggests that the fractures are a likely eruption path between the small magma chamber and the surface.
Achauer, U.; Evans, J.R.; Stauber, D.A.
Three-dimensional P velocity structure of the crust below Newberry Volcano, Oregon
Utilizing teleseismic P residuals, we have detected a column of high P velocity material extending from within 10 km of the surface below the summit of Newberry Volcano, Oregon to midcrustal depths near 25 km. We interpret this column to be the expression of a swarm of predominantly subsolidus gabbroic sills and dikes which were intruded as the volcano was built. The high P velocities observed below the volcano severely limit the size of magma chambers which could presently exist in the crust below Newberry Volcano. Those possible include a few percent of partial melt distributed through large volumes of a mafic intrusion zone in the midcrust; a few smaller, higher melt fraction zones in the midcrust with dimensions less than 6 km and whose aggregate volume is only a few percent of enclosing volumes of 200 km/sup 3/; small magma bodies with dimensions of a few kilometers located within the upper 10 km of the crust; or a mafic, crystal-rich magma of arbitrary dimensions located in the upper few km. The low P velocities detected in the upper 4 km beneath the center of the summit caldera may be partially caused by a magma chamber in the second of these catagories.
Stauber, D.A.; Green, S.M.; Iyer, H.M.
Measuring water velocity using DIDSON and image cross-correlation techniques
To design or operate hydroelectric facilities for maximum power generation and minimum ecological impact, it is critical to understand the biological responses of fish to different flow structures. However, information is still lacking on the relationship between fish behavior and flow structures despite many years of research. Existing field characterization approaches conduct fish behavior studies and flow measurements separately and coupled later using statistical analysis. These types of studies, however, lack a way to determine the specific hydraulic conditions or the specific causes of the biological response. The Dual-Frequency Identification Sonar (DIDSON) has been in wide use for fish behavior studies since 1999. The DIDSON can detect acoustic targets at long ranges in dark or turbid dark water. PIV is a state-of-the-art, non-intrusive, whole-flow-field technique, providing instantaneous velocity vector measurements in a whole plane using image cross-correlating techniques. There has been considerable research in the development of image processing techniques associated with PIV. This existing body of knowledge is applicable and can be used to process the images taken by the DIDSON. This study was conducted in a water flume which is 9 m long, 1.2 m wide, and 1.2 m deep when filled with water. A lab jet flow was setup as the benchmark flow to calibrate DIDSON images. The jet nozzle was 6.35 cm in diameter and core jet velocity was 1.52 m/s. Different particles were used to seed the flow. The flow was characterized based on the results using Laser Doppler Velocimetry (LDV). A DIDSON was mounted about 5 meters away from the jet nozzle. Consecutive DIDSON images with known time delay were divided into small interrogation spots after background was subtracted. Across-correlation was then performed to estimate the velocity vector for each interrogation spot. The estimated average velocity in the core zone was comparable to that obtained using a LDV. This proof-of-principle project demonstrated the feasibility of extracting water flow velocity information from underwater DIDSON images using image cross-correlation techniques.
Deng, Zhiqun; Mueller, Robert P.; Richmond, Marshall C.
In-cylinder gas velocity measurements comparing crankcase and blower scavenging in a fired two-stroke cycle engine
The in-cylinder flow field of a Schnuerle (loop) scavenged two-stroke engine has been examined under conditions simulating both blower and crankcase driven scavenging. Measurements of the radial component of velocity were obtained along the cylinder centerline during fired operation at delivery ratios of 0.4, 0.6, and 0.8. Both mean velocity profiles and root mean square velocity fluctuations near top center show a strong dependence on the scavenging method. Complementary in-cylinder pressure measurements indicate that combustion performance is better under blower driven scavenging for the engine geometry studied.
Miles, P.C.; Green, R.M.; Witze, P.O.
Molecular Dynamics Simulation of Smaller Granular Particles Deposition on a Larger One Due to Velocity Sequence Dependent Electrical Charge Distribution
Deposition of smaller granular particles on a larger nucleus particle has been simulated in two-dimension using molecular dynamics method. Variation of sequences of velocity of deposited particles is conducted and reported in this work. The sequences obey a normal distribution function of velocity with the same parameters. It has been observed that for velocity in range of 0 to 0.02 the densest deposited site (15-17 % number of grains) is located at about angle {\\pi}/4 where location of injection point is {\\pi}/4. And the less dense is about {\\pi}/4 + {\\pi}/2. Different sequences give similar result.
Euis Sustini; Siti Nurul Khotimah; Ferry Iskandar; Sparisoma Viridi
Comparisons of computed and measured three-dimensional velocity fields in a motored two-stroke engine
Computer simulations are compared with measurements of the three-dimensional, unsteady scavenging flows of a motored two-stroke engine. Laser Doppler velocimetry measurements were made on a modified Suzuki DT-85 ported engine. Calculations were performed using KIVA-3, a computer program that efficiently solves the intake and exhaust port flows along with those in the cylinder. Measured and computed cylinder pressures and velocities are compared. Pressures agree well over the cycle as do the velocities at the intake ports. In-cylinder velocities differ in detail, but the tumbling motion in the cylinder is well replicated in vertical plane passing through the cylinder axis. 20 refs., 7 figs., 3 tabs.
Amsden, A.A.; O'Rourke, P.J.; Butler, T.D. (Los Alamos National Lab., NM (United States)); Meintjes, K.; Fansler, T.D. (General Motors Research Labs., Warren, MI (United States))
Galactic fountains and their connection with high and intermediate velocity clouds
The aim of this paper is to calculate the expansion law and chemical enrichment of a supershell powered by the energetic feedback of a typical Galactic OB association at various galactocentric radii. We study then the orbits of the fragments created when the supershell breaks out and we compare their kinetic and chemical properties with the available observations of high - and intermediate - velocity clouds. We use the Kompaneets (1960) approximation for the evolution of the superbubble driven by sequential supernova explosions and we compute the abundances of oxygen and iron residing in the thin cold supershell. We assume that supershells are fragmented by means of Rayleigh-Taylor instabilities and we follow the orbit of the clouds either ballistically or by means of a hybrid model considering viscous interaction between the clouds and the extra-planar gas.Given the self-similarity of the Kompaneets solutions, clouds are always formed ~ 448 pc above the plane. If the initial metallicity is solar, the pollution from dying stars of the OB association has a negligible effect on the chemical composition of the clouds. The maximum height reached by the clouds above the plane seldom exceeds 2 kpc and when averaging over different throwing angles, the landing coordinate differs from the throwing coordinate ~ 1 kpc at most. The range of heights and [O/Fe] ratios spun by our clouds suggest us that the high velocity clouds cannot have a Galactic origin, whereas intermediate velocity clouds have kinematic properties similar to our modeled clouds but overabundance observed for the [O/Fe] ratios which can be reproduced only with initial metallicities which are too low compared for those of the Galaxy disk.
E. Spitoni; S. Recchi; F. Matteucci
Cold Reactive Collisions between Laser-Cooled Ions and Velocity-Selected Neutral Molecules
We report a new experimental method to study reactive ion-molecule collisions at very low temperatures. A source of laser-cooled ions in a linear Paul trap has been combined with a quadrupole-guide velocity selector to investigate the reaction of Ca{sup +} with CH{sub 3}F at collision energies E{sub coll}/k{sub B}{>=}1 K with single-particle sensitivity. The technique represents a general approach to study reactive collisions between ions and polar molecules over a wide temperature range down to the cold regime.
Willitsch, Stefan; Bell, Martin T.; Gingell, Alexander D.; Procter, Simon R.; Softley, Timothy P. [Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford OX1 3TA (United Kingdom)
The velocity pattern of a fan loop structure within a solar active region over the temperature range 0.15-1.5 MK is derived using data from the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. The loop is aligned toward the observer's line of sight and shows downflows (redshifts) of around 15 km s{sup -1} up to a temperature of 0.8 MK, but for temperatures of 1.0 MK and above the measured velocity shifts are consistent with no net flow. This velocity result applies over a projected spatial distance of 9 Mm and demonstrates that the cooler, redshifted plasma is physically disconnected from the hotter, stationary plasma. A scenario in which the fan loops consist of at least two groups of 'strands'-one cooler and downflowing, the other hotter and stationary-is suggested. The cooler strands may represent a later evolutionary stage of the hotter strands. A density diagnostic of Mg VII was used to show that the electron density at around 0.8 MK falls from 3.2 Multiplication-Sign 10{sup 9} cm{sup -3} at the loop base, to 5.0 Multiplication-Sign 10{sup 8} cm{sup -3} at a projected height of 15 Mm. A filling factor of 0.2 is found at temperatures close to the formation temperature of Mg VII (0.8 MK), confirming that the cooler, downflowing plasma occupies only a fraction of the apparent loop volume. The fan loop is rooted within a so-called outflow region that displays low intensity and blueshifts of up to 25 km s{sup -1} in Fe XII {lambda}195.12 (formed at 1.5 MK), in contrast to the loop's redshifts of 15 km s{sup -1} at 0.8 MK. A new technique for obtaining an absolute wavelength calibration for the EIS instrument is presented and an instrumental effect, possibly related to a distorted point-spread function, that affects velocity measurements is identified.
Young, P. R. [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); O'Dwyer, B.; Mason, H. E. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
We present a method to characterize statistically the parameters of a detached binary sample-binary fraction, separation distribution, and mass-ratio distribution-using noisy radial velocity data with as few as two, randomly spaced, epochs per object. To do this, we analyze the distribution of {Delta}RV{sub max}, the maximum radial velocity difference between any two epochs for the same object. At low values, the core of this distribution is dominated by measurement errors, but for large enough samples there is a high-velocity tail that can effectively constrain the parameters of the binary population. We discuss our approach for the case of a population of detached white dwarf (WD) binaries with separations that are decaying via gravitational wave emission. We derive analytic expressions for the present-day distribution of separations, integrated over the star formation history of the Galaxy, for parameterized initial WD separation distributions at the end of the common-envelope phase. We use Monte Carlo techniques to produce grids of simulated {Delta}RV{sub max} distributions with specific binary population parameters, and the same sampling cadences and radial velocity errors as the observations, and we compare them to the real {Delta}RV{sub max} distribution to constrain the properties of the binary population. We illustrate the sensitivity of the method to both the model and observational parameters. In the particular case of binary WDs, every model population predicts a merger rate per star which can easily be compared to specific Type Ia supernova rates. In a companion paper, we apply the method to a sample of {approx}4000 WDs from the Sloan Digital Sky Survey. The binary fractions and separation distribution parameters allowed by the data indicate a rate of WD-WD mergers per unit stellar mass in the Galactic disk, {approx}1 Multiplication-Sign 10{sup -13} mergers yr{sup -1} M{sup -1}{sub Sun }, remarkably similar to the rate per unit mass of Type Ia supernovae in Milky Way like galaxies.
Maoz, Dan; Badenes, Carles [School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel); Bickerton, Steven J., E-mail: firstname.lastname@example.com, E-mail: firstname.lastname@example.com, E-mail: email@example.com [Department of Astrophysical Sciences, Princeton University, Peyton Hall, Ivy Lane, Princeton, NJ 08544-1001 (United States)
Complete CFD analysis of a Velocity XL-5 RG with flight-test verification
The Texas A&M Flight Research Laboratory (FRL) recently received delivery of its newest aircraft, the Velocity XL-5 RG. The Velocity can fly faster than the other aircraft owned by the FRL and does not have a propeller in the front of the aircraft to disrupt the air flow. These are definite advantages that make the Velocity an attractive addition to the FRL inventory to be used in boundary-layer stability and transition control. Possible mounting locations built into the aircraft for future projects include hard points in the wings and roof of the fuselage. One of the drawbacks of the aircraft is that it has a canard ahead of the main wing that could disrupt the incoming flow for a wing glove or research requiring test pieces mounted to the hard point in the wing. Therefore, it is necessary to understand the influence the canard and the impact of its wake on the wing of the aircraft before any in-depth aerodynamic research could be completed on the aircraft. A combination of in-flight measurements of the canard wake and Computational Fluid Dynamics (CFD) were used to provide a clear picture of the flowfield around the aircraft. The first step of the project consisted of making a 3-D CAD model of the aircraft. This model was then used for the CFD simulations in Fluent. 2-D, 3-D, inviscid, and viscous simulations were preformed on the aircraft. A pressure rake was designed to house a 5-hole probe and 18 Pitot probes that extended forward of the main wing to measure the location and strength of the canard wake at various flight conditions. There were five primary test points that were recorded at multiple times over the course of three flights. Once all of the data were collected from the flights, the freestream conditions became the inputs into the final, 3-D CFD simulations on the aircraft. The good agreement between the CFD results and the in-flight measurements provided the necessary verification of the CFD model of the aircraft. These results can be used in the future planning and execution of experiments involving the Velocity XL-5 RG.
Schouten, Shane Michael
We examine the velocity distribution function (VDF) in dark matter halos from Milky Way to cluster mass scales. We identify an empirical model for the VDF with a wider peak and a steeper tail than a Maxwell-Boltzmann distribution, and discuss physical explanations. We quantify sources of scatter in the VDF of cosmological halos and their implication for direct detection of dark matter. Given modern simulations and observations, we find that the most significant uncertainty in the VDF of the Milky Way arises from the unknown radial position of the solar system relative to the dark matter halo scale radius.
Mao, Yao-Yuan; Strigari, Louis E.; Wechsler, Risa H.; Hahn, Oliver [Kavli Institute for Particle Astrophysics and Cosmology and Physics Department, Stanford University, Stanford, CA 94305, USAAND (United States) [Kavli Institute for Particle Astrophysics and Cosmology and Physics Department, Stanford University, Stanford, CA 94305, USAAND (United States); SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Wu, Hao-Yi [Currently at Physics Department, The University of Michigan, Ann Arbor, MI 48109, USA. (United States)] [Currently at Physics Department, The University of Michigan, Ann Arbor, MI 48109, USA. (United States)
EPRI Environmental Control Technology Center: FGD Wet Scrubber Performance At High Flue Gas Velocities
This report summarizes the impact of operating a wet flue gas desulfurization scrubber system at high flue gas velocities up to 20ft/sec (6.1 m/sec). It includes results for countercurrent spray, tray, and packing designs a variety of nozzle types. The report also describes the effect of adding dibasic acid and the impact of operation of state-of-the-art mist elimination systems. These results will be useful for planning compliance with SO2 emission regulations whether a new system is planned or addition...
Generation of Ultrahigh-Velocity Ionizing Shocks with Petawatt-Class Laser Pulses
Ultrahigh-velocity shock waves (approx10 000 km/s or 0.03c) are generated by focusing a 350-TW laser pulse into low-density helium gas. The collisionless ultrahigh-Mach-number electrostatic shock propagates from the plasma into the surrounding gas, ionizing gas as it becomes collisional. The shock undergoes a corrugation instability due to propagation of the ionizing shock within the gas (the Dyakov-Kontorovich instability). This system may be relevant to the study of very high-Mach-number ionizing shocks in astrophysical situations.
Nilson, P. M.; Mangles, S. P. D.; Willingale, L.; Kaluza, M. C.; Thomas, A. G. R.; Najmudin, Z.; Evans, R. G.; Dangor, A. E.; Krushelnick, K. [Department of Physics, Imperial College, London SW7 2AZ United Kingdom (United Kingdom); Tatarakis, M.; Lancaster, K. L. [Technological Educational Institute of Crete, Romanou, 3-GR73133 Chania (Greece); Clarke, R. J. [CLF, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon., OX11 0QX United Kingdom (United Kingdom); Karsch, S. [Max-Planck Institut fuer Quantenoptik, Hans-Kopfermann-Strasse, D-85748, Garching (Germany); Schreiber, J. [Max-Planck Institut fuer Quantenoptik, Hans-Kopfermann-Strasse, D-85748, Garching (Germany); Ludwig-Maximilians-Universistaet Munchen, Am Coulombwall, D-85748, Garching (Germany)
Comparative Study of Ultimate Saturation Velocity in Zigzag and Chiral Carbon Nanotubes
Charge transfer mechanism in carbon nanotubes (CNTs) from the scattering-limited Ohmic transport to high-field-initiated ballistic transport is studied. It is shown that the electrons changes their motion from randomness (in equilibrium) to streamlined one (in non-equilibrium) when high electric field is applied. The intrinsic velocity is discussed in non-parabolic semiconducting limits considering the nondegenerate and degenerate situations. The results obtained are significant in extracting carrier transport properties from experimental data on CNTs and in understanding the fundamental processes controlling the charge transport in nanoscale devices.
Applications of a Velocity Dealiasing Scheme to Data from the China New Generation Weather Radar System (CINRAD)
An improved velocity dealiasing algorithm is developed as an extension of the Next Generation Weather Radar (NEXRAD) dealiasing algorithm. The algorithm described in this paper is evaluated on selected China Next Generation Weather Radar (CINRAD) ...
Guangxin He; Gang Li; Xiaolei Zou; Peter Sawin Ray
Velocity Measurements at Six Fish Screening Facilities in the Yakima River Basin, Washington, Summer 1988 : Annual Report.
The Bonneville Power Administration (BPA), the United States Bureau of Reclamation (USSR), and the Washington State Department of Ecology (WDOE) are funding the construction and evaluation of fish passage facilities and fish protection facilities at irrigation and hydroelectric diversions in the Yakima River Basin, Washington State. The program provides offsite enhancement to compensate for fish and wildlife losses caused by hydroelectric development throughout the Columbia River Basin, and addresses natural propagation of salmon to help mitigate the impact of irrigation in the Yakima River Basin. This report evaluates the flow characteristics of the screening facilities. Studies consisted of velocity measurements taken in front of the rotary drum screens and within the fish bypass systems during peak flows. Measurements of approach velocity and sweep velocity were emphasized in these studies; however, vertical velocity was also measured. 5 refs., 18 figs., 15 tabs.
Performance of Maximum Likelihood Estimators of Mean Power and Doppler Velocity with A Priori Knowledge of Spectral Width
The performance of the maximum likelihood (ML) estimates of mean velocity and signal power for Doppler radar and Doppler lidar, assuming known signal spectral width, is presented. The results are compared with the theoretical limit of the Cramerñ...
Rod Frehlich
Turbulent Velocity-Variance Profiles in the Stable Boundary Layer Generated by a Nocturnal Low-Level Jet
Profiles of mean winds and turbulence were measured by the High Resolution Doppler lidar in the strong-wind stable boundary layer (SBL) with continuous turbulence. The turbulence quantity measured was the variance of the streamwise wind velocity ...
Robert M. Banta; Yelena L. Pichugina; W. Alan Brewer
A Dual-Pulse Repetition Frequency Scheme for Mitigating Velocity Ambiguities of the NOAA P-3 Airborne Doppler Radar
To mitigate some of the deleterious effects of the relatively small unambiguous Doppler velocity range (Nyquist interval) of airborne X-band Doppler radars, a technique has been developed to extend this interval. This technique, termed the batch-...
David P. Jorgensen; Tom R. Shepherd; Alan S. Goldstein
Quasi-Periodic Releases of Streamer Blobs and Velocity Variability of the Slow Solar Wind near the Sun
We search for persistent and quasi-periodic release events of streamer blobs during 2007 w