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1

Diesel Mechanics: Electrical Systems.  

ERIC Educational Resources Information Center

This publication is the second in a series of three texts for a diesel mechanics curriculum. Its purpose is to teach the concepts related to electricity and circuitry in a diesel trade. The text contains nine units. Each instructional unit includes some or all of these basic components: unit and specific (performance) objectives, suggested…

Foutes, William; And Others

2

Electrical and Mechanical Evaluation of RUWS (Remote Unmanned Work System) Prototype Cables. Volume I.  

National Technical Information Service (NTIS)

Two prototype electro-mechanical cables were evaluated electrically and mechanically to determine the suitability of the design and of the manufacturing process to the requirements of the Navy's Remote Unmanned Work System, RUWS. Electrical measurements i...

F. G. White R. C. Burgener G. L. Thomas P. T. Gibson H. A. Cress

1973-01-01

3

Micro Electric Mechanical Systems (MEMS) Test Structures: 3-Point Analysis  

NSDL National Science Digital Library

This page offers a program that calculates strain due to change in length of a beam. Written by Janet Marshall of the Micro Electric Mechanical Systems (MEMS) division of the National Institute of Standards and Technology (NIST), this three-point formula program is the result of research on multi-layered microelectronics such as silicon chips. The program is intended for use by MEMS lab workers but would work well as part of a college-level engineering class exercise. Users can choose either a cantilevered or a fixed-fixed beam and then input sample data (a sample data set is provided) into a form to get an output of strain gradient and out-of-plane curvature. A link to a page showing the formulae used is provided.

4

Wind-turbine mechanical to electrical conversion systems  

Microsoft Academic Search

The electrical energy output of Variable-Speed, Constant-Frequency (VSCF) and Constant-Speed, Constant-Frequency (CSCF) electric generation schemes for wind power plants in a power grid is analyzed on the basis of power-duration curves. A sample calculation shows that VSCF systems have a slightly higher energy output than comparable CSCF systems. In both systems the output is primarily dependent on the generator efficiency.

R. T. Smith; T. S. J. Devaiah

1976-01-01

5

Electrical Systems. Auto Mechanics Curriculum Guide Module 2. Instructor's Guide.  

ERIC Educational Resources Information Center

This document is one of a series of modules in the Missouri Auto Mechanics Curriculum Guide, which is based on 144 basic auto mechanics competencies identified on the Missouri Auto Mechanics Competency Profile. The instructor's materials in this document are for a 14-unit secondary education course. The following units are included: (1) principles…

Hevel, David; Donovan, Roger

6

Design and research on electrical\\/mechanical hybrid four-redundancy Brushless DC Motor system  

Microsoft Academic Search

Redundancy structure is widely adopted by motors in aircrafts and special vehicles with rigorous reliability requirements. This paper presents an electrical\\/mechanical hybrid four-redundancy brushless DC motor (BLDCM) and the corresponding driving control system. High reliability can be achieved by adopting the electrical\\/mechanical hybrid structure. An engineering prototype is designed and developed whereas the reliability of the BLDCM is analyzed theoretically.

Hong Guo; Wei Wang; Wei Xing; Yanming Li

2008-01-01

7

Measurement of mechanical and electrical energy flows in the semiactive piezoelectric shunt damping system  

Microsoft Academic Search

The analysis of the mechanical and electric energy flows in the semiactive vibration control system, which is made of a piezoelectric actuator shunted by a negative capacitor, is presented. The vibration control system is designed to suppress the vibration transmission in a narrow frequency range. Using a proper adjustment of the electronic circuit elements, the transmissibility of vibrations has been

Jan Václavík; Pavel Mokrý

2012-01-01

8

Bilingual Skills Training Program. Auto Mechanics. Module 4.0: The Automotive Electrical System.  

ERIC Educational Resources Information Center

This module on the automotive electrical system is the fourth of six (CE 028 296-301) in the auto mechanics course of a bilingual skills training program (A Vocabulary Development Workbook is available as CE 028 294.) The course is designed to furnish theoretical and laboratory experience. Module objectives are for students to develop…

Northern New Mexico Community Coll., El Rito.

9

Modeling cardiac mechano-electrical feedback using reaction-diffusion-mechanics systems  

NASA Astrophysics Data System (ADS)

In many practically important cases, wave propagation described by the reaction-diffusion equation initiates deformation of the medium. Mathematically, such processes are described by coupled reaction-diffusion-mechanics (RDM) systems. RDM systems were recently used to study the effects of deformation on wave propagation in cardiac tissue, so called mechano-electrical feedback (MEF). In this article, we review the results of some of these studies, in particular those relating to the effects of deformation on pacemaker activity and spiral wave dynamics in the heart. We also provide brief descriptions of the numerical methods used, and the underlying cardiac physiology.

Keldermann, R. H.; Nash, M. P.; Panfilov, A. V.

2009-06-01

10

System Analysis of Blood Circulation Based on Coherence Power Transfer: From Electrical Driving to Mechanical Vibration  

NASA Astrophysics Data System (ADS)

We analyze blood circulation based on the basis of the system viewpoint and coherence power transfer from electrical energy (ECG) to mechanical power (blood pressure wave). The coherent oscillation between the driving signal and the vibration of the cardiovascular system is investigated by coherence function and the perturbations of the system are found. In addition, we develop a mathematical equation to describe the phenomenon. The average peak coherence value S for the first five harmonics is utilized as an index to quantify the power coherence effect. The evaluated p-value (< 0.01) reveals that the distinction of power coherence between the healthy subjects and cardiovascular patients is significant. Consequently, we conclude that if the S approaches a value close to one, the output is almost completely attributed to input and fewer perturbation signals influence the system; therefore, the cardiovascular system stays in a better condition. Conversely, if S approaches a value less than one, larger perturbations will worsen the cardiovascular system condition.

Wei, Ching?Chuan; Lo, Pei?Chen; Wu, Lin?Kun

2006-04-01

11

Mechanical Systems  

NASA Technical Reports Server (NTRS)

The presentation provides an overview of requirement and interpretation letters, mechanical systems safety interpretation letter, design and verification provisions, and mechanical systems verification plan.

Davis, Robert E.

2002-01-01

12

Mechanical and Electrical Design of the Fermilab Lithium Lens and Transformer System.  

National Technical Information Service (NTIS)

A lithium-lens focusing device will be used for the collection of 8-GeV antiprotons in the Fermilab Tevatron I Project. The details of the mechanical and electrical design of the Fermilab lens and its associated toroidal transformer are discussed. The len...

G. Dugan C. Hojvat A. J. Lennox G. Biallas F. Cilyo

1983-01-01

13

Design and Use of Interactive Learning Stations in Construction Education for Building Mechanical, Electrical, and Plumbing Systems  

NSDL National Science Digital Library

Over the past several years, the building codes that govern the design and installation of mechanical and electrical systems for buildings have become increasingly prescriptive in nature, specifying detailed information related to the design and installation of the systems, while offering no reasoning behind their prescriptive measures. Students now read about the design and installation of these systems in textbooks, and using the building codes, have in-class exercises drafting the systems, which in industry are used for fabrication and installation. Therefore, in conjunction with a new curriculum proposed for the construction management department at California Polytechnic State University (Cal Poly), San Luis Obispo an interactive learning station was developed for student use to enhance student learning. This paper focuses on the design and use of interactive learning stations for building mechanical, electrical, and plumbing (MEP) systems that allow construction students to perform hands-on fit-up exercises and test their performance.

Korman, Thomas; Simonian, Lonny

2009-10-16

14

Mechanical Electrical and Plumbing Course Syllabus  

NSDL National Science Digital Library

This document is a course syllabus for Shannon Baird's Mechanical Electrical and Plumbing class, taught at Portland Community College. The course "covers the basic principles, types, and applications of mechanical, electrical and plumbing systems in commercial construction." This syllabus includes a detailed course schedule, including concepts to be covered each week. This document may be downloaded in PDF file format.

Baird, Shannon

2011-12-27

15

Electric turbocompound control system  

DOEpatents

Turbocompound systems can be used to affect engine operation using the energy in exhaust gas that is driving the available turbocharger. A first electrical device acts as a generator in response to turbocharger rotation. A second electrical device acts as a motor to put mechanical power into the engine, typically at the crankshaft. Apparatus, systems, steps, and methods are described to control the generator and motor operations to control the amount of power being recovered. This can control engine operation closer to desirable parameters for given engine-related operating conditions compared to actual. The electrical devices can also operate in "reverse," going between motor and generator functions. This permits the electrical device associated with the crankshaft to drive the electrical device associated with the turbocharger as a motor, overcoming deficient engine operating conditions such as associated with turbocharger lag.

Algrain, Marcelo C. (Dunlap, IL)

2007-02-13

16

Type Toyota Management Systems (MSTT) of Small and Medium-Sized Enterprises in Mechanical and Electrical Industry  

Microsoft Academic Search

\\u000a This paper gives an overview and considers the most recent aspects of a study, dealing with the topic of Type Toyota Management\\u000a Systems. In the survey SMEs in mechanical and electrical industry have been asked. On the one hand, a questionnaire for a\\u000a mass evaluation was used and on the other hand specialists have been interviewed orally for the specific

Stefan Kluge; Andreas Rau; Engelbert Westkämper

2009-01-01

17

Electrical power generation by mechanically modulating electrical double layers.  

PubMed

Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future. PMID:23403587

Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

2013-01-01

18

Mechanical and electrical design of the Fermilab lithium lens and transformer system  

SciTech Connect

A lithium-lens focusing device will be used for the collection of 8-GeV antiprotons in the Fermilab Tevatron I Project. The details of the mechanical and electrical design of the Fermilab lens and its associated toroidal transformer are discussed. The lens, with a radium of 1 cm and length 15 cm, is expected to achieve gradients of 1000 T/m for a focal distance of 0.225 m. The gradient requires a current on the order of 5 x 10/sup 5/A, resulting in large electromagnetic and thermal stresses. The power-supply discharge current and the effect of the inductance of the power leads and connections are minimized by the use of a toroidal matching transformer surrounding the lens itself.

Dugan, G.; Hojvat, C.; Lennox, A.J.; Biallas, G.; Cilyo, F.; Leininger, M.; McCarthy, J.; Sax, W.; Snowdon, S.

1983-03-01

19

Mechanical and electrical design of the Fermilab lithium lens and transformer system  

SciTech Connect

A lithium lens focusing device will be used for the collection of 8 GeV antiprotons in the Fermilab Tevatron I Project. The details of the mechanical and electrical design of the Fermilab lens and its associated toroidal transformer are discussed. The lens, with a radius of 1 cm and length 15 cm, is expected to achieve gradients of 1000 T/m for a focal distance of 0.225 m. The gradient requires a current on the order of 5x10/sup 5/A, resulting in large electromagnetic and thermal stresses. The power supply discharge current and the effect of the inductance of the power leads and connections are minimized by the use of a toroidal matching transformer surrounding the lens itself.

Dugan, G.; Biallas, G.; Cilyo, F.; Hojvat, C.; Leininger, M.; Lennox, A.J.; McCarthy, J.; Sax, W.; Snowdon, S.

1983-08-01

20

Fuel and Electrical Systems Mechanic. Apprenticeship Training Standards = Mecanicien de systemes d'alimentation en carburant et electriques. Normes de formation en apprentissage.  

ERIC Educational Resources Information Center

These training standards for fuel and electrical systems mechanics are intended to be used by apprentice/trainees, instructors, and companies in Ontario, Canada, as a blueprint for training or as a prerequisite for prerequisite for accreditation/certification. The training standards identify skills required for this occupation and its related…

Ontario Ministry of Skills Development, Toronto.

21

Electrical Mechanical Maintenance. Instructor's Guide.  

ERIC Educational Resources Information Center

This instructor's guide describes the development of a sixteen-week postsecondary course in electrical mechanical maintenance. Following introductory sections that provide background information and a course summary, the third section describes the instructional model used in the course. Section 4 presents an overview of instructional media used…

Santa Clara County Superintendent of Schools, San Jose, CA.

22

Combined electrical and mechanical model of electric submersible pumps  

Microsoft Academic Search

The electric submersible pump unit consists of a pump powered by a medium-voltage three-phase induction motor. The power transmission system is integrated with the riser pipes. Starting the pump causes heavy dynamic stresses on the motor shaft and the mechanical connection between pump (impellers) and shaft. The motor and its load will generate transient torque pulsations that may be damaging

Olav Vaag Thorsen; Magnus Dalva

2001-01-01

23

Electrical System Compliance Guideline.  

National Technical Information Service (NTIS)

Electrical systems for many types of boats are complex. The regulations have selected critical areas pertaining to electrical systems from the standpoint of safety and stipulate requirements to assure good practice in these areas. Some requirements may be...

1978-01-01

24

Wind power electrical generator system  

Microsoft Academic Search

A wind power electrical generator system having improved efficiency including a wind mill which activates an air compressor to generate a supply of pressurized air. An air motor activated by the supply of pressurized air drives a generator to produce electrical power. A waste air recovery mechanism, activated by the waste air from the air motor produces rotary energy assisting

Allison

1984-01-01

25

On the Mechanisms of Electromagnetic Interference Between Electrical Power Systems and Neighboring Pipelines  

Microsoft Academic Search

The mechanisms of electromagnetic interference between a power line and a neighboring pipeline using electromagnetic field theory are discussed based on a simple right-of-way scenario. First, the field theory approach is used to model the complete conductor network under consideration, as is. The inductive, capacitive and conductive interference effects between all the elements in the network are simultaneously taken into

Robert Southey; Farid Dawalibi; Jinxi Ma

2000-01-01

26

Developing a mechanical roadway system for waste energy capture of vehicles and electric generation  

Microsoft Academic Search

Energy requirement of vehicles could be said the second large energy consumption aside from industry. An extremely large percentage (ca. 85%) consumed energy by vehicles is converted to waste heat, i.e. invalid work. To improve working efficiency of vehicles and to retrieve waste energy from vehicles are two essential energy topics in the 21st century. This work presents a mechanical

Chen-Ching Ting; Da-Yi Tsai; Chung-Cheng Hsiao

2012-01-01

27

Reliability indices applied to performance-based mechanisms in electric power distribution systems  

Microsoft Academic Search

Power system failures are random events and their prevention can be managed by the regulatory agencies through pre-established\\u000a performance targets. Once a standard or target is established for a certain performance index, it is assumed to be the limit\\u000a value that must not be overstepped or it may cause penalties for the utility. Penalty based schemes, although very popular\\u000a among

A. M. Leite da Silva; L. C. Nascimento; A. C. R. Guimarães; J. C. O. Mello

2010-01-01

28

Electrical Transmission Line Diametrical Retention Mechanism  

DOEpatents

The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within downhole components. The invention allows a transmission line to be attached to the internal diameter of drilling components that have a substantially uniform drilling diameter. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to withstand the tension and compression of drill pipe during routine drilling cycles.

Hall, David R. (Provo, UT); Hall, Jr., H. Tracy (Provo, UT); Pixton, David (Lehi, UT); Dahlgren, Scott (Provo, UT); Sneddon, Cameron (Provo, UT); Briscoe, Michael (Lehi, UT); Fox, Joe (Spanish Fork, UT)

2006-01-03

29

112. VIEW OF SOUTH SIDE OF MECHANICAL AND ELECTRICAL ROOM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

112. VIEW OF SOUTH SIDE OF MECHANICAL AND ELECTRICAL ROOM (110), LSB (BLDG. 770). VEHICLE MECHANICAL SYSTEMS ROOM (111) AND PNEUMATIC SUPPLY PANEL VISIBLE AT SOUTH END OF MECHANICAL AND ELECTRICAL ROOM (110). PAYLOAD CABLE DISTRIBUTION BOX ON LEFT OF PHOTO, FACING WEST. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

30

Advanced electric power systems  

Microsoft Academic Search

An identification and preliminary evaluation was made of alternative advanced electric power systems which have been suggested for possible future use by the American electric utility industry. The motivation for interest in advanced power systems stems primarily from the rapidly rising costs of clean fossil fuels, especially conventional fuel oil, and uncertainties of fuel supply. Four basic energy sources have

Albert J. Giramonti; Robert D. Lessard

1975-01-01

31

Electrical system architecture  

DOEpatents

An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

Algrain, Marcelo C. (Peoria, IL) [Peoria, IL; Johnson, Kris W. (Washington, IL) [Washington, IL; Akasam, Sivaprasad (Peoria, IL) [Peoria, IL; Hoff, Brian D. (East Peoria, IL) [East Peoria, IL

2008-07-15

32

49 CFR 236.308 - Mechanical or electric locking or electric circuits; requisites.  

Code of Federal Regulations, 2010 CFR

...Mechanical or electric locking or electric circuits; requisites. 236.308...Mechanical or electric locking or electric circuits; requisites. Mechanical or electric locking or electric circuits shall be installed...

2010-10-01

33

49 CFR 236.308 - Mechanical or electric locking or electric circuits; requisites.  

Code of Federal Regulations, 2010 CFR

...Mechanical or electric locking or electric circuits; requisites. 236.308...Mechanical or electric locking or electric circuits; requisites. Mechanical or electric locking or electric circuits shall be installed...

2009-10-01

34

Robot drive mechanism uses conventional electric motors  

NASA Astrophysics Data System (ADS)

The development and use of three phase asynchronous electric motors in robot technology are presented. The mechanical arm of a robot has as many drives as it has joints. Manipulators in use in modern industry must have six to nine degrees of mobility, and experimental prototypes with 18 coordinates of movement are already developed. A simple, common, and inexpensive industrial electric motor is proposed for use in the robots. This motor was previously considered unsuitable for delicate work because of its low precision in executing commands and the difficulty in controlling it. Control methods were developed to overcome this difficulty. Integrated microcircuits and a power converter control the operation of the single motor. A cassette made up of six units controls the operation of the whole mechanical arm. This cassette is linked with the brain of the robot (a microprocessor system or microcomputer).

Demchenko, I.

1986-02-01

35

T & I--Auto Mechanics. Electrical System. Kit No. 48. Instructor's Manual [and] Student Learning Activity Guide.  

ERIC Educational Resources Information Center

An instructor's manual and student activity guide on auto electrical systems are provided in this set of prevocational education materials which focuses on the vocational area of trade and industry. (This set of materials is one of ninety-two prevocational education sets arranged around a cluster of seven vocational offerings: agriculture, home…

Lake, Robert

36

Hawaii electric system reliability.  

SciTech Connect

This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

Silva Monroy, Cesar Augusto; Loose, Verne William

2012-09-01

37

Preliminary Hazards Assessments for Space Nuclear Electric Propulsion Systems Mechanisms to Quantitatively Ascertain and Address Launch and Operational Risks  

NASA Astrophysics Data System (ADS)

Architectures are analyzed based on several figures of merit, including mass transported to Mars and samples transported from Mars to Earth, potential to reduce Earth contamination, sites on MArs visited, trip time and potential cost trades.A technological variant of a commercial vehicle for near-Earth missions is used as the nuclear electric propulsion system baseline. Several types of Mars landing and ascent vehicles are proposed and assessed.Technology approaches are assessed and analyzed to compare risk to a conventionally fueled Mars Sample Return concept. Also compared are solar electric propelled missions to ascertain cost saving or advantages. Various mission departure dates will be proposed and analyzed.

Lenard, R.

2002-01-01

38

Electrical Systems. FOS: Fundamentals of Service.  

ERIC Educational Resources Information Center

This electrical systems manual is one of a series of power mechanics texts and visual aids for training in the servicing of electrical systems on mobile machines. Materials provide basic information and illustrations for use by vocational students and teachers as well as shop servicemen and laymen. The ten chapters focus on (1) Electricity: How It…

John Deere Co., Moline, IL.

39

Diesel Electrical Systems. Teacher Edition (Revised).  

ERIC Educational Resources Information Center

This module is one of a series of teaching guides that cover diesel mechanics. The module contains eight instructional units that cover the following topics: (1) introduction to electrical systems; (2) electrical circuits; (3) electrical indicator circuits; (4) storage batteries; (5) starting systems and circuits; (6) ignition circuits; (7)…

Sprinkle, Tom; Huston, Jane, Ed.

40

Electrical Systems Standards Analysis.  

National Technical Information Service (NTIS)

This report describes the background study made on Electrical Systems. Included is a master list of Marine Standards Organizations that were used for this study. Statements in these standards are divided into categories as being testable, visual examinati...

1973-01-01

41

Modeling of a Spring\\/Damper System for Electrical Contacts using Dynamic Designer in Autodesk Mechanical Desktop  

Microsoft Academic Search

Extreme space limitations and the desire to reduce the bounce between contacts prompted an investigation of the use of Belleville washers and Sorbothane as part of a spring\\/damper system in a medium voltage high-speed shorting device. Experimental tests in conjunction with mechanism simulation have been used to optimize a spring and damping system for the minimization of bounce that occurs

Mary B. Groff

42

Mechanical systems: A compilation  

NASA Technical Reports Server (NTRS)

A compilation of several mechanized systems is presented. The articles are contained in three sections: robotics, industrial mechanical systems, including several on linear and rotary systems and lastly mechanical control systems, such as brakes and clutches.

1975-01-01

43

Electric utility engineer's FGD manual -- Volume 2: Major mechanical equipment; FGD proposal evaluations; Use of FGDPRISM in FGD system modification, proposal, evaluation, and design; FGD system case study. Final report.  

National Technical Information Service (NTIS)

Part 2 of this manual provides the electric utility engineer with detailed technical information on some of the major mechanical equipment used in the FGD system. The objectives of Part 2 are the following: to provide the electric utility engineer with in...

1996-01-01

44

Electrical and Mechanical Passive Network Synthesis  

Microsoft Academic Search

The context of this paper is the application of electrical circuit synthesis to problems of mechanical control. The use of\\u000a the electrical-mechanical analogy and the inerter mechanical element is briefly reviewed. Classical results from passive network\\u000a synthesis are surveyed including Brune’s synthesis, Bott-Duffin’s procedure, Darlington’s synthesis, minimum reactance extraction\\u000a and the synthesis of biquadratic functions. New results are presented on

Michael Chen; Malcolm Smith

45

RHIC magnet electrical system  

NASA Astrophysics Data System (ADS)

The RHIC magnet electrical system consists primarily of the power converters that are used to energize the superconducting magnets in the collider ring, the power distribution system (both room temperature and superconducting) to deliver that power from the converters to the magnets, a detection system to monitor for quenches in the magnets and superconducting cables, and a protection system to remove power from the superconductors if a quench is detected. This system also has major interfaces with the Control System for commands, status monitoring, current setting and analog monitoring of the power supplies, and with Conventional Facilities for power distribution of the mains at and below the 480VAC level.

Bruno, D.; Eng, W.; Feng, P. K.; Ganetis, G.; Lambiase, R. F.; Louie, W.

2003-03-01

46

Basic Electricity in Agricultural Mechanics.  

ERIC Educational Resources Information Center

This unit of instruction on electricity has been designed especially for teachers to use with freshmen and sophomore vocational agricultural students in Montana. It consists of an outline of the unit and eight lesson plans. The unit outline lists the following components: situation, aims and goals, lesson plans, student activities, teacher…

Montana State Univ., Bozeman. Dept. of Agricultural and Industrial Education.

47

Solar electric systems  

NASA Astrophysics Data System (ADS)

Subjects discussed in connection with solar electricity are related to solar radiation fundamentals, wind electric conversion and utilization, the basic theory of solar cells, photovoltaic materials, photovoltaic technology, components of solar thermal electric systems, solar thermal power plants, and integrated solar thermal electric complexes. The solar technology development in the Arab world is also examined, taking into account the horizon of solar energy in the Arab countries, solar energy activities at the Scientific Research Council in Iraq, solar energy activities at the Royal Scientific Society in Jordan, the solar energy program at Kuwait Institute for Scientific Research, application of solar energy in Libya, prospects of solar energy for Egypt, solar energy programs in Qatar, performance characteristics of a 350 kW photovoltaic power system for Saudi Arabian villages, nonconventional energy in Syria, wind and solar energies in Sudan, solar electric research and development program in Tunisia, and solar energy research and utilization in Yemen Arab Republic. No individual items are abstracted in this volume

Warfield, G.

48

US electric power system reliability  

NASA Astrophysics Data System (ADS)

Electric energy supply, transmission and distribution systems are investigated in order to determine priorities for legislation. The status and the outlook for electric power reliability are discussed.

49

Electric generation system  

US Patent & Trademark Office Database

To utilize solar energy without loosing the laminating function. For this purpose, there is provided an electric generation system for generating an electric power utilizing solar energy falling on a transparent plate 7 dividing a predetermined interior space 8 from an exterior space, characterized in that the transparent plate 7 is provided with a thin plate-like or film-like thermal generation module 11, which is transmissive to at least a portion of visible rays in the solar energy, and which generates an electromotive force by a temperature difference between a temperature in the interior space and a temperature in the exterior space. Consequently, electric power can be generated utilizing heat resulting from blocking the light entering into the interior space 8.

2013-10-29

50

Electric power transmission systems  

Microsoft Academic Search

An updated edition (from 1972) of technical aspects exhibited by electric systems which transmit power from the generator to the loads. A new area covered is the calculation of short-circuit currents due to symetrical faults and their impact on the ratings of circuit-interrupting devices. Not only have problems been added, but the use of a computer (over a wide-range of

J. R. Eaton; E. Cohen

1983-01-01

51

Electrical Connector Mechanical Seating Sensor  

NASA Technical Reports Server (NTRS)

A sensor provides a measurement of the degree of seating of an electrical connector. This sensor provides a number of discrete distances that a plug is inserted into a socket or receptacle. The number of measurements is equal to the number of pins available in the connector for sensing. On at least two occasions, the Shuttle Program has suffered serious time delays and incurred excessive costs simply because a plug was not seated well within a receptacle. Two methods were designed to address this problem: (1) the resistive pin technique and (2) the discrete length pins technique. In the resistive pin approach, a standard pin in a male connector is replaced with a pin that has a uniform resistivity along its length. This provides a variable resistance on that pin that is dependent on how far the pin is inserted into a socket. This is essentially a linear potentiometer. The discrete approach uses a pin (or a few pins) in the connector as a displacement indicator by truncating the pin length so it sits shorter in the connector than the other pins. A loss of signal on this pin would indicate a discrete amount of displacement of the connector. This approach would only give discrete values of connector displacement, and at least one pin would be needed for each displacement value that would be of interest.

Arens, Ellen; Captain, Janine; Youngquist, Robert

2011-01-01

52

Market-based control mechanisms for electric power demand response  

Microsoft Academic Search

We propose a settlement mechanism for optimally scheduling real time electricity consumption which is suitable for an automated demand response control system. Our proposed settlement mechanism, supply function bidding, is interpreted as a Newton algorithm for optimization problems with decomposable structure, and it is shown to satisfy the second fundamental theorem of welfare economics for the case of affine supply

Anthony Papavasiliou; Haitham Hindi; Daniel Greene

2010-01-01

53

Trouble shooting system for an electric vehicle  

SciTech Connect

This patent describes a trouble shooting system for an electric vehicle. The electric vehicle contains a driving mechanism, a driving operation part and a control device. The driving mechanism includes a power source, an electric motor and a modality for controlling output level from the power supply to the electric motor in response to the driving operation part. The control device includes a microprocessor which receives commands from the driving operation part and supplies a control signal to the driving mechanism in response to a stored drive control program. The trouble shooting system consists of control device storage mechanisms for storing trouble shooting programs for various parts of the vehicle which are executed by the microprocessor. This system also includes a command generating modality responsive to manual operation for supplying a command to the microprocessor to initiate the execution and read out of a selected trouble shooting program and a method by which the microprocessor may display the program being processed.

Horiuchi, M.

1986-01-14

54

Electrically induced mechanical precompression of ferroelectric plates  

DOEpatents

A method of electrically inducing mechanical precompression of a ferroelectric plate covered with electrodes utilizes the change in strains of the plate as functions of applied electric field. A first field polarizes and laterally shrinks the entire plate. An outer portion of the electrodes are removed, and an opposite field partially depolarizes and expands the central portion of the plate against the shrunk outer portion.

Chen, Peter J. (Albuquerque, NM)

1987-01-01

55

49 CFR 236.308 - Mechanical or electric locking or electric circuits; requisites.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Mechanical or electric locking or electric circuits; requisites. 236.308 Section 236...Interlocking Standards § 236.308 Mechanical or electric locking or electric circuits; requisites....

2013-10-01

56

TOPEX electrical power system  

NASA Technical Reports Server (NTRS)

The TOPEX mission requirements which impact the power requirements and analyses are presented. A description of the electrical power system (EPS), including energy management and battery charging methods that were conceived and developed to meet the identified satellite requirements, is included. Analysis of the TOPEX EPS confirms that all of its electrical performance and reliability requirements have been met. The TOPEX EPS employs the flight-proven modular power system (MPS) which is part of the Multimission Modular Spacecraft and provides high reliability, abbreviated development effort and schedule, and low cost. An energy balance equation, unique to TOPEX, has been derived to confirm that the batteries will be completely recharged following each eclipse, under worst-case conditions. TOPEX uses three NASA Standard 50AH Ni-Cd batteries, each with 22 cells in series. The MPS contains battery charge control and protection based on measurements of battery currents, voltages, temperatures, and computed depth-of-discharge. In case of impending battery depletion, the MPS automatically implements load shedding.

Chetty, P. R. K.; Roufberg, Lew; Costogue, Ernest

1991-01-01

57

Mechanisms of electrical conductivity in olivine  

SciTech Connect

Data on the electrical conductivity and the thermoelectric effect in single crystals indicate that the charge conduction mechanism in pure magnesium forsterite is electrons. The concentration of electrons can be varied by controlling the number of oxygen vacancies through manipulation of the oxygen pressure. For iron bearing olivine, the conduction mechanism is by electron holes localized on an iron ion. Since iron strongly affects the creep process as well, oxidation of iron is probably accompanied by the production of magnesium vacancies. 15 references.

Schock, R.N.; Duba, A.G.; Shankland, T.J.

1984-01-01

58

Biophysical injury mechanisms in electrical shock trauma.  

PubMed

Electrical shock trauma tends to produce a very complex pattern of injury, mainly because of the multiple modes of frequency-dependent tissue-field interactions. Historically, Joule heating was thought to be the only cause of electrical injuries to tissue by commercial-frequency electrical shocks. In the last 15 years, biomedical engineering research has improved the understanding of the underlying biophysical injury mechanisms. Besides thermal burns secondary to Joule heating, permeabilization of cell membranes and direct electroconformational denaturation of macromolecules such as proteins have also been identified as tissue-damage mechanisms. This review summarizes the physics of tissue injury caused by contact with commercial-frequency power lines, as well as exposure to lightning and radio frequency (RF), microwave, and ionizing radiation. In addition, we describe the anatomic patterns of the resultant tissue injury from these modes of electromagnetic exposures. PMID:11701521

Lee, R C; Zhang, D; Hannig, J

2000-01-01

59

Effect of system parameters on size distribution of 304 stainless steel particles produced by electrical discharge mechanism  

Microsoft Academic Search

An electrical discharge machine (EDM) can be used to produce Uranium Carbide (UC) microspheres. This material is useful for dispersed nuclear fuel fabrication. To obtain empirical data about the process parameters for UC modeling, 304 stainless steel (304 SS) was used to produce microspheres. Particle size effects were analyzed via three parameters; arc intensity, dielectric medium, and pulse width. Results

Gokul Vasudevamurthy; Travis W. Knight

2007-01-01

60

Electric vehicle monitoring system  

SciTech Connect

A system is described for monitoring one or more electric vehicles which are driven by parallel-connected induction motors controlled by a variable voltage/variable frequency inverter, the induction motors being divided into a first group of one or more induction motors and a second group of one or more induction motors, comprising: rotational frequency detecting means for detecting a rotational frequency of the first group of motors; first current detecting means for detecting a first motor current supplied to the first group of motors; second current detecting means for detecting a second motor current supplied to the second group of motors; and protection circuit means responsive only to outputs of the rotational frequency detecting means and the first and second current detecting means for determining an operational parameter of the second group of motors indicative of a rotational frequency of the second group of motors.

Kojima, S.; Obi, H.

1987-08-11

61

High density electrical card connector system  

SciTech Connect

An electrical circuit board card connection system is disclosed which comprises a wedge-operated locking mechanism disposed along an edge portion of the printed circuit board. An extrusion along the edge of the circuit board mates with an extrusion fixed to the card cage having a plurality of electrical connectors. The connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned and the wedge inserted. The disclosed connection system is a simple solution to the need for a greater number of electrical signal connections.

Haggard, J.E.; Trotter, G.R.

2000-02-29

62

High density electrical card connector system  

DOEpatents

An electrical circuit board card connection system is disclosed which comprises a wedge-operated locking mechanism disposed along an edge portion of the printed circuit board. An extrusion along the edge of the circuit board mates with an extrusion fixed to the card cage having a plurality of electrical connectors. The connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned and the wedge inserted. The disclosed connection system is a simple solution to the need for a greater number of electrical signal connections.

Haggard, J. Eric (Elgin, IL); Trotter, Garrett R. (Aurora, IL)

2000-01-01

63

State space analysis of electric power systems  

Microsoft Academic Search

The dynamic analysis of a balanced three-phase electrical power system comprised of a finite set of: (1) synchronous generators, (2) induction and\\/or synchronous devices, (3) transmission line networks, (4) RL (or RLC)-loads, and (5) mechanical loads is analyzed by use of the state variable approach. Each component of the electric power system is described by its own state model. These

Glen E. Baer; Van E. Mablekos

1976-01-01

64

Mechanical vibration to electrical energy converter  

DOEpatents

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

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

2009-03-03

65

Electric space propulsion systems  

Microsoft Academic Search

Active development of electric thrustors began 10 years ago. Today, several kinds of thrustors have achieved efficiencies above 90 % and lifetimes of several thousand hours. The following article derives the basic theory of electric thrust production at constant exhaust velocity, and at variable exhaust velocity programmed for optimum vehicle performance. Electrothermal or arcjet; electrostatic or ion; and electrodynamic or

Ernst Stuhlinger

1967-01-01

66

Mechanical and electrical properties of resistance welds at cryogenic temperatures  

Microsoft Academic Search

The mechanical and electrical properties of resistance welds at cryogenic temperatures for the large superconducting magnet such as the superconducting MHD Dipole system for the National Coal-Fired Flow Facility (CFFF SCMS) at the U. of Tennessee Space Institute are reported.

S. T. Wang; S. H. Kim; N. S. Kim; H. Ludwig

1979-01-01

67

SMART1 Electrical propulsion mechanism (EPMEC)  

Microsoft Academic Search

The SMART-1 Spacecraft is due to launch in 2002 and is being developed as a test bed for various new technologies that will be needed for interplanetary missions. One of these new technologies is the Electric Propulsion system (EPS) which is to be used as the main source of thrust during the mission. Contraves Space AG were selected for the

Brian Wood; Walter Buff; Philippe Delouard

2001-01-01

68

Promising Electric Aircraft Drive Systems  

NASA Technical Reports Server (NTRS)

An overview of electric aircraft propulsion technology performance thresholds for key power system components is presented. A weight comparison of electric drive systems with equivalent total delivered energy is made to help identify component performance requirements, and promising research and development opportunities.

Dudley, Michael R.

2010-01-01

69

Electric propulsion system technology  

NASA Technical Reports Server (NTRS)

The work performed on the Ion Propulsion System Technology Task in FY90 is described. The objectives of this work fall under two broad categories. The first of these deals with issues associated with the application of xenon ion thrusters for primary propulsion of planetary spacecraft, and the second with the investigation of technologies which will facilitate the development of larger, higher power ion thrusters to support more advanced mission applications. Most of the effort was devoted to investigation of the critical issues associated with the use of ion thrusters for planetary spacecraft. These issues may be succinctly referred to as life time, system integration, and throttling. Chief among these is the engine life time. If the engines do not have sufficient life to perform the missions of interest, then the other issues become unimportant. Ion engine life time was investigated through two experimental programs: an investigation into the reduction of ion engine internal sputter erosion through the addition of small quantities of nitrogen, and a long duration cathode life test. In addition, a literature review and analysis of accelerator grid erosion were performed. The nitrogen addition tests indicated that the addition of between 0.5 and 1.0 percent of nitrogen by mass to the xenon propellant results in a reduction in the sputter erosion of discharge chamber components by a factor of between 20 and 50, with negligible reduction in thruster performance. The long duration test of a 6.35-mm dia. xenon hollow cathode is still in progress, and has accumulated more than 4,000 hours of operation at an emission current of 25 A at the time of this writing. One of the major system integration issues concerns possible interactions of the ion thruster produced charge exchange plasma with the spacecraft. A computer model originally developed to describe the behavior of mercury ion thruster charge exchange plasmas was resurrected and modified for xenon propellant. This model enables one to calculate the flow direction and local density of the charge exchange plasma, and indicates the degree to which this plasma can flow upstream of the thruster exhaust plane. A continuing effort to investigate the most desirable throttling technique for noble gas ion thrusters concentrated this year on experimentally determining the fixed flow rate throttling range of a 30-cm dia. thruster with a two-grid accelerator system. These experiments demonstrated a throttling capability which covers a 2.8 to 1 variation in input power. This throttling range is 55 percent greater than expected, and is due to better accelerator system performance at low net-to-total voltage ratios than indicated in the literature. To facilitate the development of large, higher power ion thrusters several brief studies were performed. These include the development of a technique which simulates ion thruster operation without beam extraction, the development of an optical technique to measure ion thruster grid distortion due to thermal expansion, tests of a capacitance measurement technique to quantify the accelerator system grid separation, and the development of a segmented thruster geometry which enables near term development of ion thrusters at power levels greater than 100 kW. Finally, a paper detailing the benefits of electric propulsion for the Space Exploration Initiative was written.

Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.

1991-01-01

70

Electrosensory Systems in Electric Fish.  

National Technical Information Service (NTIS)

Investigations of neuronal control of electric organs and other synchronously acting effector systems have disclosed several common properties and these studies have been extended to similar systems in other forms. The methods involve correlated psycholog...

M. V. L. Bennett

1967-01-01

71

Electrical Power Systems for MARS.  

National Technical Information Service (NTIS)

Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclea...

R. J. Giudici

1986-01-01

72

Electrical power distribution system (HV270DC), for application in more electric aircraft  

Microsoft Academic Search

In the new designs of military aircraft and unmanned aircraft there is a clear trend towards increasing demand of electrical power. This fact is mainly due to the replacement of mechanical, pneumatic and hydraulic equipments by partially or completely electrical systems. Generally, use of electrical power onboard is continuously increasing within the areas of communications, surveillance and general systems, such

D. Izquierdo; R. Azcona; F. J López del Cerro; C. Fernandez; B. Delicado

2010-01-01

73

Ferroelastic domain switching dynamics under electrical and mechanical excitations  

NASA Astrophysics Data System (ADS)

In thin film ferroelectric devices, switching of ferroelastic domains can significantly enhance electromechanical response. Previous studies have shown disagreement regarding the mobility or immobility of ferroelastic domain walls, indicating that switching behaviour strongly depends on specific microstructures in ferroelectric systems. Here we study the switching dynamics of individual ferroelastic domains in thin Pb(Zr0.2,Ti0.8)O3 films under electrical and mechanical excitations by using in situ transmission electron microscopy and phase-field modelling. We find that ferroelastic domains can be effectively and permanently stabilized by dislocations at the substrate interface while similar domains at free surfaces without pinning dislocations can be removed by either electric or stress fields. For both electrical and mechanical switching, ferroelastic switching is found to occur most readily at the highly active needle points in ferroelastic domains. Our results provide new insights into the understanding of polarization switching dynamics as well as the engineering of ferroelectric devices.

Gao, Peng; Britson, Jason; Nelson, Christopher T.; Jokisaari, Jacob R.; Duan, Chen; Trassin, Morgan; Baek, Seung-Hyub; Guo, Hua; Li, Linze; Wang, Yiran; Chu, Ying-Hao; Minor, Andrew M.; Eom, Chang-Beom; Ramesh, Ramamoorthy; Chen, Long-Qing; Pan, Xiaoqing

2014-05-01

74

Electric-Power System Simulator  

NASA Technical Reports Server (NTRS)

Shows different combinations of generation, storage, and load components: display, video monitor with keyboard input to microprocessor, and video monitor for display of load curves and power generation. Planning tool for electric utilities, regulatory agencies, and laymen in understanding basics of electric-power systems operation.

Caldwell, R. W.; Grumm, R. L.; Biedebach, B. L.

1984-01-01

75

Electric propulsion system technology  

NASA Astrophysics Data System (ADS)

The work performed in fiscal year (FY) 1991 under the Propulsion Technology Program RTOP (Research and Technology Objectives and Plans) No. (55) 506-42-31 for Low-Thrust Primary and Auxiliary Propulsion technology development is described. The objectives of this work fall under two broad categories. The first of these deals with the development of ion engines for primary propulsion in support of solar system exploration. The second with the advancement of steady-state magnetoplasmadynamic (MPD) thruster technology at 100 kW to multimegawatt input power levels. The major technology issues for ion propulsion are demonstration of adequate engine life at the 5 to 10 kW power level and scaling ion engines to power levels of tens to hundreds of kilowatts. Tests of a new technique in which the decelerator grid of a three-grid ion accelerator system is biased negative of neutralizer common potential in order to collect facility induced charge-exchange ions are described. These tests indicate that this SAND (Screen, Accelerator, Negative Decelerator) configuration may enable long duration ion engine endurance tests to be performed at vacuum chamber pressures an order of magnitude higher than previously possible. The corresponding reduction in pumping speed requirements enables endurance tests of 10 kW class ion engines to be performed within the resources of existing technology programs. The results of a successful 5,000-hr endurance of a xenon hollow cathode operating at an emission current of 25 A are described, as well as the initial tests of hollow cathodes operating on a mixture of argon and 3 percent nitrogen. Work performed on the development of carbon/carbon grids, a multi-orifice hollow cathode, and discharge chamber erosion reduction through the addition of nitrogen are also described. Critical applied-field MPD thruster technical issues remain to be resolved, including demonstration of reliable steady-state operation at input powers of hundreds to thousands of kilowatts, achievement of thruster efficiency and specific impulse levels required for missions of interest, and demonstration of adequate engine life at these input power, efficiency, and specific impulse levels. To address these issues we have designed, built, and tested a 100 kW class, radiation-cooled applied-field MPD thruster and a unique dual-beam thrust stand that enables separate measurements of the applied- and self-field thrust components. We have also initiated the development of cathode thermal and plasma sheath models that will eventually be used to guide the experimental program. In conjunction with the cathode modeling, a new cathode test facility is being constructed. This facility will support the study of cathode thermal behavior and erosion mechanisms, the diagnosis of the near-cathode plasma and the development and endurance testing of new, high-current cathode designs. To facilitate understanding of electrode surface phenomenon, we have implemented a telephoto technique to obtain photographs of the electrodes during engine operation. In order to reduce the background vacuum tank pressure during steady-state engine operation in order to obtain high fidelity anode thermal data, we have developed and are evaluating a gas-dynamic diffuser. A review of experience with alkali metal propellants for MPD thrusters led to the conclusion that alkali metals, particularly lithium, offer the potential for significant engine performance and lifetime improvements. systems-level issue is the potential for spacecraft contamination. Subsequent experimental and theoretical efforts should be directed toward verifying the performance and lifetime gains and characterizing the thruster flow field to assess its impact on spacecraft surfaces. Consequently, we have begun the design and development of a new facility to study engine operation with alkali metal propellants.

Brophy, John R.; Garner, Charles E.; Goodfellow, Keith D.; Pivirotto, Thomas J.; Polk, James E.

1992-11-01

76

Oscillation control system for electric motor drive  

DOEpatents

A feedback system for controlling mechanical oscillations in the torsionally complaint drive train of an electric or other vehicle. Motor speed is converted in a processor to estimate state signals in which a plant model which are used to electronically modify thetorque commands applied to the motor.

Slicker, James M. (Union Lake, MI); Sereshteh, Ahmad (Union Lake, MI)

1988-01-01

77

Oscillation control system for electric motor drive  

DOEpatents

A feedback system for controlling mechanical oscillations in the torsionally complaint drive train of an electric or other vehicle. Motor speed is converted in a processor to estimate state signals in which a plant model which are used to electronically modify the torque commands applied to the motor. 5 figs.

Slicker, J.M.; Sereshteh, A.

1988-08-30

78

Solar Thermal Electric Power Systems.  

National Technical Information Service (NTIS)

Results of research to identify cost effective solar thermal electric power systems are given. Parametric performance and cost models were developed for concentrating collector, heat transport, and heat storage subsystems. Dynamic programming methods to s...

1974-01-01

79

Electric utility system master plan  

SciTech Connect

This publication contains the electric utility system plan and guidelines for providing adequate electric power to the various facilities of Lawrence Livermore National Laboratory in support of the mission of the Laboratory. The topics of the publication include general information on the current systems and their operation, a planning analysis for current and future growth in energy demand, proposed improvements and expansions required to meet long range site development and the site`s five-year plan.

Erickson, O.M.

1992-10-01

80

Electric utility systems and practices  

Microsoft Academic Search

This book is a text for a college-level course or an in-house seminar for power system engineers, it also provides an in-depth survey of the electric utility system. It achieves its objectives of providing an overview of the technical challenges and opportunities in power system engineering by presenting a description of each power system component and how it integrates into

Rustebakke

1983-01-01

81

Space station electrical power system  

NASA Technical Reports Server (NTRS)

The purpose of this paper is to describe the design of the Space Station Electrical Power System. This includes the Photovoltaic and Solar Dynamic Power Modules as well as the Power Management and Distribution System (PMAD). In addition, two programmatic options for developing the Electrical Power System will be presented. One approach is defined as the Enhanced Configuration and represents the results of the Phase B studies conducted by the NASA Lewis Research Center over the last two years. Another option, the Phased Program, represents a more measured approach to reaching about the same capability as the Enhanced Configuration.

Labus, Thomas L.; Cochran, Thomas H.

1987-01-01

82

Electrical power system WP04  

Microsoft Academic Search

Viewgraphs on Space Station Freedom Electrical Power System (EPS) WP-40 are presented. Topics covered include: key EPS technical requirements; photovoltaic power module systems; solar array assembly; blanket containment box and box positioning subassemblies; solar cell; bypass diode assembly; Kapton with atomic oxygen resistant coating; sequential shunt unit; gimbal assembly; energy storage subsystem; thermal control subsystem; direct current switching unit; integrated

Donald L. Nored

1990-01-01

83

Nuclear electric propulsion systems overview  

NASA Technical Reports Server (NTRS)

The topics are presented in viewgraph form and include the following: nuclear propulsion background; schedule for the nuclear electric propulsion (NEP) project; NEP for the Space Exploration Initiative; NEP on-going systems tasks; 20KWe mission/system study; and agenda.

Doherty, Michael P.

1993-01-01

84

Electric Motor System.  

National Technical Information Service (NTIS)

The D.C.-energized brushless-motor system is useful in driving film-type recorders, as used in the exercise sections of acoustic-homing torpedoes during underwater test runs. The motor has a permanently-magnetized rotor, a specially wound stator, and a pa...

H. W. Thompson

1965-01-01

85

Electrical power systems for Mars  

NASA Astrophysics Data System (ADS)

Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

Giudici, Robert J.

1986-05-01

86

Manned spacecraft electrical power systems  

SciTech Connect

A brief history of the development of electrical power systems from the earliest manned space flights illustrates a natural trend toward growth of electrical power requirements and operational lifetimes with each succeeding space program. A review of the design philosophy and development experience associated with the Space Shuttle Orbiter electrical power system is presented, beginning with the state of technology at the conclusion of the Apollo Program. A discussion of prototype, verification, and qualification hardware is included, and several design improvements following the first Orbiter flight are described. The problems encountered, the scientific and engineering approaches used to meet the technological challenges, and the results obtained are stressed. Major technology barriers and their solutions are discussed, and a brief Orbiter flight experience summary of early Space Shuttle missions is included. A description of projected Space Station power requirements and candidate system concepts which could satisfy these anticipated needs is presented.

Simon, W.E.; Nored, D.L.

1987-03-01

87

A mechanical, thermal and electrical packaging design for a prototype power management and control system for the 30 cm mercury ion thruster  

NASA Technical Reports Server (NTRS)

A prototype electric power management and thruster control system for a 30 cm ion thruster is described. The system meets all of the requirements necessary to operate a thruster in a fully automatic mode. Power input to the system can vary over a full two to one dynamic range (200 to 400 V) for the solar array or other power source. The power management and control system is designed to protect the thruster, the flight system and itself from arcs and is fully compatible with standard spacecraft electronics. The system is easily integrated into flight systems which can operate over a thermal environment ranging from 0.3 to 5 AU. The complete power management and control system measures 45.7 cm (18 in.) x 15.2 cm (6 in.) x 114.8 cm (45.2 in.) and weighs 36.2 kg (79.7 lb). At full power the overall efficiency of the system is estimated to be 87.4 percent. Three systems are currently being built and a full schedule of environmental and electrical testing is planned.

Sharp, G. R.; Gedeon, L.; Oglebay, J. C.; Shaker, F. S.; Siegert, C. E.

1978-01-01

88

Electro-mechanical propulsion system  

SciTech Connect

An Electro-Mechanical Propulsion System for vehicles, wherein the prime mover, such as an internal combustion engine, drives an alternating voltage generator through a first shaft at a constant RPM controlled by a speed governor; and wherein the alternating voltage generator serves as a source of energy for an electrical energy conversion unit comprising a controlled rectifier, a polyphase signal generator, an analog control unit, and a regulated DC power supply, to further provide a variable power and frequency source for an AC traction motor coupled through a second shaft to the vehicle wheel drive system. Operator manual or pedal control of the system is further provided by a speed control potentiometer, An acceleration control potentiometer, and a torque control potentiometer.

Stewart, C.F.; Stewart, J.K.

1984-04-24

89

A market mechanism for electric power transmission  

Microsoft Academic Search

As competition is introduced into the electric power industry, access and pricing policy for transmission will play a pivotal role in shaping future market structure and performance. The externalities associated with the loop flow phenomenon in an electric power network constitute a significant barrier to the formation of efficient markets for electricity and transmission services. In this paper, we present

Hung-Po Chao; Stephen Peck

1996-01-01

90

Dust-Tolerant Intelligent Electrical Connection System  

NASA Technical Reports Server (NTRS)

Faults in wiring systems are a serious concern for the aerospace and aeronautic (commercial, military, and civilian) industries. Circuit failures and vehicle accidents have occurred and have been attributed to faulty wiring created by open and/or short circuits. Often, such circuit failures occur due to vibration during vehicle launch or operation. Therefore, developing non-intrusive fault-tolerant techniques is necessary to detect circuit faults and automatically route signals through alternate recovery paths while the vehicle or lunar surface systems equipment is in operation. Electrical connector concepts combining dust mitigation strategies and cable diagnostic technologies have significant application for lunar and Martian surface systems, as well as for dusty terrestrial applications. The dust-tolerant intelligent electrical connection system has several novel concepts and unique features. It combines intelligent cable diagnostics (health monitoring) and automatic circuit routing capabilities into a dust-tolerant electrical umbilical. It retrofits a clamshell protective dust cover to an existing connector for reduced gravity operation, and features a universal connector housing with three styles of dust protection: inverted cap, rotating cap, and clamshell. It uses a self-healing membrane as a dust barrier for electrical connectors where required, while also combining lotus leaf technology for applications where a dust-resistant coating providing low surface tension is needed to mitigate Van der Waals forces, thereby disallowing dust particle adhesion to connector surfaces. It also permits using a ruggedized iris mechanism with an embedded electrodynamic dust shield as a dust barrier for electrical connectors where required.

Lewis, Mark; Dokos, Adam; Perotti, Jose; Calle, Carlos; Mueller, Robert; Bastin, Gary; Carlson, Jeffrey; Townsend, Ivan, III; Immer, Chirstopher; Medelius, Pedro

2012-01-01

91

44. LOCK, ELECTRICAL SYSTEM, HAULAGE ENGINES, ELECTRICAL DETAILS AND LOCATION. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

44. LOCK, ELECTRICAL SYSTEM, HAULAGE ENGINES, ELECTRICAL DETAILS AND LOCATION. February 1938 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

92

Advanced aircraft electric power system  

SciTech Connect

The role of electric energy in both military and commercial aircraft increases in importance with every advancement in airframe performance and avionic technology. Microcircuits and volatile memories impact power continuity and quality, digital flight control and stability augmentation require high reliability. This paper presents the system concept, hardware development and status of the Navy program.

Segrest, J.D.

1981-01-01

93

Uniform System of Accounts: Electric.  

National Technical Information Service (NTIS)

This bulletin sets forth, in a more user-friendly format, the RUS Uniform System of Accounts (USoA) and accounting interpretations for electric borrowers. This bulletin is a reprint of already codified policies and procedures found in 7 CFR Part 1767, Acc...

1995-01-01

94

Formation mechanism of electrical damage on sliding lubricated contacts for steel pair under DC electric field  

Microsoft Academic Search

A dynamic electrical pitting tester has been developed to investigate the effects of supply voltage, supply current, and oil film thickness on the electrical behavior, the normal and frictional forces, and the formation mechanism of electric damage for the sliding lubricated contacts of steel pair under DC electric field. Based on the experimental results for the normal and frictional forces,

Yuang-Cherng Chiou; Rong-Tsong Lee; Sing-Ming Lin

2009-01-01

95

Electric utility engineer`s FGD manual -- Volume 2: Major mechanical equipment; FGD proposal evaluations; Use of FGDPRISM in FGD system modification, proposal, evaluation, and design; FGD system case study. Final report  

SciTech Connect

Part 2 of this manual provides the electric utility engineer with detailed technical information on some of the major mechanical equipment used in the FGD system. The objectives of Part 2 are the following: to provide the electric utility engineer with information on equipment that may be unfamiliar to him, including ball mills, vacuum filters, and mist eliminators; and to identify the unique technique considerations imposed by an FGD system on more familiar electric utility equipment such as fans, gas dampers, piping, valves, and pumps. Part 3 provides an overview of the recommended procedures for evaluating proposals received from FGD system vendors. The objectives are to provide procedures for evaluating the technical aspects of proposals, and to provide procedures for determining the total costs of proposals considering both initial capital costs and annual operating and maintenance costs. The primary objective of Part 4 of this manual is to provide the utility engineer who has a special interest in the capabilities of FGDPRISM [Flue Gas Desulfurization PRocess Integration and Simulation Model] with more detailed discussions of its uses, requirements, and limitations. Part 5 is a case study in using this manual in the preparation of a purchase specification and in the evaluation of proposals received from vendors. The objectives are to demonstrate how the information contained in Parts 1 and 2 can be used to improve the technical content of an FGD system purchase specification; to demonstrate how the techniques presented in Part 3 can be used to evaluate proposals received in response to the purchase specification; and to illustrate how the FGDPRISM computer program can be used to establish design parameters for the specification and evaluate vendor designs.

NONE

1996-03-04

96

Engineering graphene mechanical systems.  

PubMed

We report a method to introduce direct bonding between graphene platelets that enables the transformation of a multilayer chemically modified graphene (CMG) film from a "paper mache-like" structure into a stiff, high strength material. On the basis of chemical/defect manipulation and recrystallization, this technique allows wide-range engineering of mechanical properties (stiffness, strength, density, and built-in stress) in ultrathin CMG films. A dramatic increase in the Young's modulus (up to 800 GPa) and enhanced strength (sustainable stress ?1 GPa) due to cross-linking, in combination with high tensile stress, produced high-performance (quality factor of 31,000 at room temperature) radio frequency nanomechanical resonators. The ability to fine-tune intraplatelet mechanical properties through chemical modification and to locally activate direct carbon-carbon bonding within carbon-based nanomaterials will transform these systems into true "materials-by-design" for nanomechanics. PMID:22764747

Zalalutdinov, Maxim K; Robinson, Jeremy T; Junkermeier, Chad E; Culbertson, James C; Reinecke, Thomas L; Stine, Rory; Sheehan, Paul E; Houston, Brian H; Snow, Eric S

2012-08-01

97

Types of Electric Propulsion Systems  

NASA Technical Reports Server (NTRS)

As presented by Gerhard Heller of Marshall Space Flight Center's Research Projects Division in 1961, this chart illustrates three basic types of electric propulsion systems then under consideration by NASA. The ion engine (top) utilized cesium atoms ionized by hot tungsten and accelerated by an electrostatic field to produce thrust. The arc engine (middle) achieved propulsion by heating a propellant with an electric arc and then producing an expansion of the hot gas or plasma in a convergent-divergent duct. The electromagnetic, or MFD engine (bottom) manipulated strong magnetic fields to interact with a plasma and produce acceleration.

1961-01-01

98

Current status and future trends in More Electric Car power systems  

Microsoft Academic Search

Increasing use of electrical power to drive automobile subsystems, which historically have been driven by a combination of mechanical, hydraulic, and electrical power transfer systems, is seen as a dominant trend in advanced automotive power systems. This is the concept of More Electric Cars (MEC). Advancements in the areas of power electronics, fault tolerant electrical power distribution systems, electric drives,

J. M. Miller; A. Emadi; A. V. Rajarathnam; M. Ehsani

1999-01-01

99

Cavity optoelectromechanical system combining strong electrical actuation with ultrasensitive transduction  

SciTech Connect

A cavity optoelectromechanical system is reported which combines the ultrasensitive transduction of cavity optomechanical systems with the electrical actuation of nanoelectromechanical systems. Ultrasensitive mechanical transduction is achieved via optomechanical coupling. Electrical gradient forces as large as 0.40 {mu}N are realized, facilitating strong actuation with ultralow dissipation. A scanning probe microscope is implemented, capable of characterizing the mechanical modes. The integration of electrical actuation into optomechanical devices is an enabling step toward the regime of quantum nonlinear dynamics and provides capabilities for quantum control of mechanical motion.

McRae, Terry G. [Department of Physics, University of Queensland, St. Lucia, Queensland 4072 (Australia); MacDiarmid Institute, Physics Department, University of Otago, Dunedin (New Zealand); Lee, Kwan H.; Harris, Glen I.; Knittel, Joachim; Bowen, Warwick P. [Department of Physics, University of Queensland, St. Lucia, Queensland 4072 (Australia)

2010-08-15

100

Shunt regulation electric power system  

NASA Technical Reports Server (NTRS)

A regulated electric power system having load and return bus lines is described. A plurality of solar cells interconnected in a power supplying relationship and having a power shunt tap point electrically spaced from the bus lines is provided. A power dissipator is connected to the shunt tap point and provides for a controllable dissipation of excess energy supplied by the solar cells. A dissipation driver is coupled to the power dissipator and controls its conductance and dissipation and is also connected to the solar cells in a power taping relationship to derive operating power therefrom. An error signal generator is coupled to the load bus and to a reference signal generator to provide an error output signal which is representative of the difference between the electric parameters existing at the load bus and the reference signal generator. An error amplifier is coupled to the error signal generator and the dissipation driver to provide the driver with controlling signals.

Wright, W. H.; Bless, J. J. (inventors)

1971-01-01

101

Understanding the thermal, mechanical and electrical properties of epoxy nanocomposites  

Microsoft Academic Search

In the present work, the electrical, mechanical and thermal properties of epoxy nanocomposite materials were studied. The electrical insulation characteristics were analyzed through short time breakdown voltage test, accelerated electrical ageing test, and by tracking test. The breakdown voltage increases with increase in nano-clay content up to 5wt%, under AC and DC voltages. The volume resistivity, permittivity and tan(?) of

R. Sarathi; R. K. Sahu; P. Rajeshkumar

2007-01-01

102

Methods for characterization of mechanical and electrical prosthetic vacuum pumps.  

PubMed

Despite increasingly widespread adoption of vacuum-assisted suspension systems in prosthetic clinical practices, there remain gaps in the body of scientific knowledge guiding clinicians' choices of existing products. In this study, we identified important pump-performance metrics and developed techniques to objectively characterize the evacuation performance of prosthetic vacuum pumps. The sensitivity of the proposed techniques was assessed by characterizing the evacuation performance of two electrical (Harmony e-Pulse [Ottobock; Duderstadt, Germany] and LimbLogic VS [Ohio Willow Wood; Mt. Sterling, Ohio]) and three mechanical (Harmony P2, Harmony HD, and Harmony P3 [Ottobock]) prosthetic pumps in bench-top testing. Five fixed volume chambers ranging from 33 cm(3) (2 in.(3)) to 197 cm(3) (12 in.(3)) were used to represent different air volume spaces between a prosthetic socket and a liner-clad residual limb. All measurements were obtained at a vacuum gauge pressure of 57.6 kPa (17 inHg). The proposed techniques demonstrated sensitivity to the different electrical and mechanical pumps and, to a lesser degree, to the different setting adjustments of each pump. The sensitivity was less pronounced for the mechanical pumps, and future improvements for testing of mechanical vacuum pumps were proposed. Overall, this study successfully offers techniques feasible as standards for assessing the evacuation performance of prosthetic vacuum pump devices. PMID:24458892

Komolafe, Oluseeni; Wood, Sean; Caldwell, Ryan; Hansen, Andrew; Fatone, Stefania

2013-01-01

103

More-electric aircraft electrical power system accelerated functional modeling  

Microsoft Academic Search

The development of future more-electric aircraft (MEA) is a major trend in modern aircraft electric power system (EPS) engineering that results in a significantly increased number of onboard loads driven by power-electronics. Development of appropriate EPS architectures, ensuring the power system integrity, stability and assessment of overall system quality and performance under possible normal and abnormal scenarios requires extensive simulation

S. V. Bozhko; T. Wu; Y. Tao; G. M. Asher

2010-01-01

104

Mechanical design and driving mechanism of an isokinetic functional electrical stimulation-based leg stepping trainer.  

PubMed

The mechanical design of a constant velocity (isokinetic) leg stepping trainer driven by functional electrical stimulation-evoked muscle contractions was the focus of this paper. The system was conceived for training the leg muscles of neurologically-impaired patients. A commercially available slider crank mechanism for elliptical stepping exercise was adapted to a motorized isokinetic driving mechanism. The exercise system permits constant-velocity pedalling at cadences of 1-60 rev x min(-1). The variable-velocity feature allows low pedalling forces for individuals with very weak leg muscles, yet provides resistance to higher pedalling effort in stronger patients. In the future, the system will be integrated with a computer-controlled neuromuscular stimulator and a feedback control unit to monitor training responses of spinal cord-injured, stroke and head injury patients. PMID:18274073

Hamzaid, N A; Fornusek, C; Ruys, A; Davis, G M

2007-12-01

105

Electrical impedance controls mechanical sensing in ionic polymer metal composites  

NASA Astrophysics Data System (ADS)

Ionic polymer metal composites (IPMCs) are a class of soft electroactive materials that are recently finding extensive application as mechanical sensors and energy harvesters in liquids. In their most fundamental form, IPMCs are composed of a hydrated ionomeric membrane that is sandwiched between two electrochemically deposited metal electrodes. Ionomer swelling, counterion diffusion, and the formation of electric double layers are some of the physical phenomena underpinning energy transduction in IPMCs; however, a thorough understanding of the relative influence of such phenomena is yet to be established. Here, we propose a physics-based modeling framework, based on the Poisson-Nernst-Planck system, to describe IPMC chemoelectrical response to an imposed time-varying flexural deformation. We utilize the method of matched asymptotic expansions to compute a closed-form solution for the electric potential and counterion concentration in the IPMC. The model predicts that IPMC sensing is independent of the time rate of deformation and linearly correlated to the mechanical curvature, with a coefficient of proportionality that is a function of the ionomer thickness and the temperature. Thus, our results demonstrate that the characterization of IPMC electrical impedance suffices to identify all the parameters that are relevant to sensing, in contrast with the current state of knowledge. Theoretical results are validated through experiments on patterned in-house fabricated IPMC samples that are subject to time-varying flexural deformations.

Cha, Youngsu; Cellini, Filippo; Porfiri, Maurizio

2013-12-01

106

Manned spacecraft electrical power systems  

NASA Technical Reports Server (NTRS)

A brief history of the development of electrical power systems from the earliest manned space flights illustrates a natural trend toward a growth of electrical power requirements and operational lifetimes with each succeeding space program. A review of the design philosophy and development experience associated with the Space Shuttle Orbiter electrical power system is presented, beginning with the state of technology at the conclusion of the Apollo Program. A discussion of prototype, verification, and qualification hardware is included, and several design improvements following the first Orbiter flight are described. The problems encountered, the scientific and engineering approaches used to meet the technological challenges, and the results obtained are stressed. Major technology barriers and their solutions are discussed, and a brief Orbiter flight experience summary of early Space Shuttle missions is included. A description of projected Space Station power requirements and candidate system concepts which could satisfy these anticipated needs is presented. Significant challenges different from Space Shuttle, innovative concepts and ideas, and station growth considerations are discussed. The Phase B Advanced Development hardware program is summarized and a status of Phase B preliminary tradeoff studies is presented.

Simon, William E.; Nored, Donald L.

1987-01-01

107

107. OVERHEAD REFRIGERANT PIPING AND ELECTRICAL TERMINALS FOR SYSTEM 2 ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

107. OVERHEAD REFRIGERANT PIPING AND ELECTRICAL TERMINALS FOR SYSTEM 2 CONTROLS IN MECHANICAL EQUIPMENT ROOM (201), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

108

Development of a DC propulsion system for an electric vehicle  

Microsoft Academic Search

The suitability of the Eaton automatically shifted mechanical transaxle concept for use in a near-term dc powered electric vehicle is evaluated. A prototype dc propulsion system for a passenger electric vehicle was designed, fabricated, tested, installed in a modified Mercury Lynx vehicle and track tested at the contractor's site. The system consisted of a two-axis, three-speed, automatically-shifted mechanical transaxle, 15.2

W. L. Kelledes

1984-01-01

109

Direct Drive Options for Electric Propulsion Systems.  

National Technical Information Service (NTIS)

Power processing units (PPU's) in an electric propulsion system provide many challenging integration issues. The PPU must provide power to the electric thruster while maintaining compatibility with all of the spacecraft power and data systems. Inefficienc...

J. A. Hamley

1995-01-01

110

Apollo Lunar Module Electrical Power System Overview  

NASA Technical Reports Server (NTRS)

Objectives include: a) Describe LM Electrical System original specifications; b) Describe the decision to change from fuel cells to batteries and other changes; c) Describe the Electrical system; and d) Describe the Apollo 13 failure from the LM perspective.

Interbartolo, Michael

2009-01-01

111

Research for Electric Energy Systems  

SciTech Connect

This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field exposure system. The second investigation is concerned with two different activities: the detection of trace levels of S{sub 2}F{sub 10} in SF{sub 6} and the development of an improved stochastic analyzer for pulsating phenomena (SAPP). The detection of S{sub 2}F{sub 10} in the presence of SF{sub 6} using mass-spectrometric detection coupled to a gas chromatograph is difficult because of the similar mass spectra. A technique is described that enables the detection of S{sub 2}F{sub 10} in gaseous SF{sub 6} down to the ppb level using a modified gas chromatograph-mass spectrometer. The new system was applied to an investigation of the stochastic behavior of negative corona (Trichel pulses) and the effect of a dielectric barrier on these discharges. The third investigation is concerned with breakdown and prebreakdown phenomena in liquid dielectrics. The activity reported here was a study of negative steamers preceding electric breakdown in hexanes. Using the image preserving optical delay, the growth of the streamers associated with partial discharges at a point cathode are photographed at high magnification. The last investigation is concerned with the evaluation and improvement of methods for measuring fast transients in electrical power systems such as might be associated with an electromagnetic impulse. A compact resistive divider, NIST4, was designed. It is anticipated that this divider together with some Kerr electro-optical devices will be used as the reference system at NIST.

Anderson, W.E. (ed.)

1991-06-01

112

Electrical and mechanical design criteria for EHV and UHV: overhead transmission lines  

SciTech Connect

The results are presented of a program devoted to the selection of electrical and mechanical design criteria and parameters for overhead power transmission lines for ac systems rated at from 345 to 1100 kV and for dc systems rated at from 600 to 1200 kV. Information is included on the environmental effects, i.e., audible noise and electric fields, of the lines, mechanical and economic requirements, safety, failures, grounding, and lightning protection. (LCL)

Not Available

1980-06-01

113

Insight into the mechanisms of neuronal processing from electric fish.  

PubMed

Weakly electric fish use their electric fields to locate objects and communicate with each other. Their electric discharges vary with species, gender, and social status. This variation is mediated by steroid and peptide hormones that influence ion currents through changes in gene expression or phosphorylation state. Understanding how electric fish decode the perturbations of their electric fields that result from interactions with the discharges of other fish or prey is illuminating general mechanisms of neuronal processing. Their central sensory circuits are specialized to process amplitude modulated signals, to detect microsecond variations in spike timing, and are dynamically reconfigured depending on the stimulus parameters. PMID:14662377

Zakon, Harold H

2003-12-01

114

Propulsion systems for Light Electric Vehicles  

Microsoft Academic Search

The paper is concerned with the development of the propulsion system for two Light Electric Vehicles (LEVs), namely a city scooter and an electric bicycle. The propulsion system of the city scooter consists of a wheel motor for the traction and a lithium-ion battery for the energy storage. The propulsion system of the electric bicycle utilizes a fuel cell assisted

Manuele Bertoluzzo; Giuseppe Buja

2010-01-01

115

Powertrain system for a hybrid electric vehicle  

DOEpatents

A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration.

Reed, Jr., Richard G. (Royal Oak, MI); Boberg, Evan S. (Hazel Park, MI); Lawrie, Robert E. (Whitmore Lake, MI); Castaing, Francois J. (Bloomfield Township, MI)

1999-08-31

116

Powertrain system for a hybrid electric vehicle  

DOEpatents

A hybrid electric powertrain system is provided including an electric motor/generator drivingly engaged with the drive shaft of a transmission. The electric is utilized for synchronizing the rotation of the drive shaft with the driven shaft during gear shift operations. In addition, a mild hybrid concept is provided which utilizes a smaller electric motor than typical hybrid powertrain systems. Because the electric motor is drivingly engaged with the drive shaft of the transmission, the electric motor/generator is driven at high speed even when the vehicle speed is low so that the electric motor/generator provides more efficient regeneration. 34 figs.

Reed, R.G. Jr.; Boberg, E.S.; Lawrie, R.E.; Castaing, F.J.

1999-08-31

117

Solar energy thermally powered electrical generating system  

NASA Technical Reports Server (NTRS)

A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

Owens, William R. (Inventor)

1989-01-01

118

Electrical modeling of Piezoelectric ceramics for analysis and evaluation of sensory systems  

Microsoft Academic Search

Piezoelectricity is an ability of some materials to generate an electric potential in response to applied mechanical stress. Piezoelectric ceramics are often used for sensory systems to monitor mechanical characteristics of structures through an electrical signal. Thus, to support system level analysis and evaluation of sensory systems, understanding and estimating the electrical behavior of piezoelectric ceramics with a minimum effort

Jina Kim; Benjamin L. Grisso; Jeong K. Kim; Dong Sam Ha; Daniel J. Inman

2008-01-01

119

The neutron electric dipole moment and the Weinberg mechanism  

SciTech Connect

We gave an overview of various mechanism for CP violation paying special attention to their prediction of the neutron electric dipole moment. The implication of the recent developments associated with the color electric dipole moment of gluon in various models of CP-violation are then critically assessed. 25 refs.

Chang, D. (Northwestern Univ., Evanston, IL (USA). Dept. of Physics and Astronomy Fermi National Accelerator Lab., Batavia, IL (USA))

1990-01-01

120

31. Closeup view of the electrical and mechanical rail connections ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Closeup view of the electrical and mechanical rail connections between the two spans facing north; 'pins' and electrical connection. Both spans are down and locked. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA

121

Electrical system for a motor vehicle  

DOEpatents

In one embodiment of the present invention, an electrical system for a motor vehicle comprises a capacitor, an engine cranking motor coupled to receive motive power from the capacitor, a storage battery and an electrical generator having an electrical power output, the output coupled to provide electrical energy to the capacitor and to the storage battery. The electrical system also includes a resistor which limits current flow from the battery to the engine cranking motor. The electrical system further includes a diode which allows current flow through the diode from the generator to the battery but which blocks current flow through the diode from the battery to the cranking motor.

Tamor, Michael Alan (Toledo, OH)

1999-01-01

122

Electrical system for a motor vehicle  

DOEpatents

In one embodiment of the present invention, an electrical system for a motor vehicle comprises a capacitor, an engine cranking motor coupled to receive motive power from the capacitor, a storage battery and an electrical generator having an electrical power output, the output coupled to provide electrical energy to the capacitor and to the storage battery. The electrical system also includes a resistor which limits current flow from the battery to the engine cranking motor. The electrical system further includes a diode which allows current flow through the diode from the generator to the battery but which blocks current flow through the diode from the battery to the cranking motor. 2 figs.

Tamor, M.A.

1999-07-20

123

Electrical and Mechanical Characteristics of Epoxy-Nanoclay Composite  

Microsoft Academic Search

In this study, we investigated the effects of nanoclay additives on the electrical and mechanical properties of diglycidyl ether of bisphenol A (DGEBA) epoxy resin. Epoxy-clay nanocomposites were synthesized using organically modified two montmorillonite clays (MMT) with different interlamellar spacing (31.5 Å and 18.5 Å). The electrical and mechanical properties of epoxy-clay nanocopomosites were measured with variation of the amount

Hyun-Ji Noh; Sung-Pill Nam; Sung-Gap Lee; Byeong-Lib Ahn; Woo-Sik Won; Hyoung-Gwan Woo; Sang-Man Park

2009-01-01

124

Nanosatellite electrical power system development  

NASA Astrophysics Data System (ADS)

Nanosatellites have the potential to carry out the complex work of today's larger satellites at a fraction of the cost. Their small designs drastically reduce launch costs and allow many research projects and technology demonstration missions to be flown. The development of small satellites has created a need for smaller, lightweight electrical power systems (EPS) without compromising the power capacity. This thesis focuses on the electrical power system of the YUsend-1 mission. The work carried out in designing and developing the EPS for the YUsend mission utilizing commercial technologies is outlined. Mission modes are developed and a power budget is assigned for the different subsystems setting a baseline for how much power is needed. Different battery chemistries are analyzed in order to find a type that would suit the needs of the YUsend program. Commercially available batteries are put through space environment testing and the results are presented. The fabrication, testing, and space qualification results of solar panels using Triangular Advanced Solar Cells (TASCs) are also presented. Lastly the layout for the distribution board is developed.

Navarathinam, Nimal

125

High current capacity electrical corrosive electrolyte battery electrical interconnection system  

Microsoft Academic Search

This patent describes a battery electrical connection system for use with corrosive electrolyte batteries. It comprises: battery terminals, each being integrally attached to a plate strap within a battery; conductor cables, each securely cast and engaged into one of the battery terminals to form an electrical connection; conductor cable insulation; battery seals integral with and extending the exterior of the

E. J. Ward; T. C. I. I. Ward

1990-01-01

126

ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

The purpose of this revision of the System Description Document (SDD) is to establish requirements that drive the design of the electrical power system and their bases to allow the design effort to proceed to License Application. This SDD is a living document that will be revised at strategic points as the design matures over time. This SDD identifies the requirements and describes the system design as they exist at this time, with emphasis on those attributes of the design provided to meet the requirements. This SDD has been developed to be an engineering tool for design control. Accordingly, the primary audience are design engineers. This type of SDD leads and follows the design process. It leads the design process with regard to the flow down of upper tier requirements onto the system. Knowledge of these requirements is essential to performing the design process. This SDD follows the design with regard to the description of the system. The description provided in the SDD is a reflection of the results of the design process to date. Functional and operational requirements applicable to this system are obtained from ''Project Functional and Operational Requirements'' (F&OR) (Siddoway, 2003). Other requirements to support the design process have been taken from higher level requirements documents such as ''Project Design Criteria Document'' (PDC) (Doraswamy 2004), the fire hazards analyses, and the preclosure safety analysis. The above mentioned low-level documents address ''Project Requirements Document'' (PRD) (Canori and Leitner 2003) requirements. This SDD includes several appendices with supporting information. Appendix B lists key system charts, diagrams, drawings, and lists; and Appendix C is a list of system procedures.

M. Maniyar

2004-06-22

127

Rotatable electric cable connecting system  

NASA Technical Reports Server (NTRS)

A cable reel assembly is described which is particularly adapted for, but not limited to, a system for providing electrical connection of power and data signals between an orbiter vehicle, such as a space shuttle, and a recovered satellite. The assembly is comprised of two mutually opposing ring type structures having 180 deg relative rotation with one of the structures being held in fixed position while the other structure is rotatable. Motor controlled berthing latches and umbilical cable connectors for the satellite are located on the rim of the rotatable ring structure. The electrical cable assembly is fed in two sections from the orbiter vehicle into the outer rim portion of the fixed ring structure where they are directed inwardly and attached to two concentrically coiled metal bands whose respective ends are secured to inner and outer post members of circular sets of guide pins located on opposing circular plate members, one rotatable and one fixed. The cable sections are fed out as three output cable sections through openings in the central portion of the circular plate of the rotatable ring structure where they are directed to the latches and connectors located on its rim.

Manges, D. R. (inventor)

1985-01-01

128

A ballscrew drive mechanism with piezo-electric nut for preload and motion control  

Microsoft Academic Search

This work reports the development of a ballscrew drive mechanism equipped with a piezo-electric nut for active ballscrew preload and fine motion control. This mechanism is intended for a motion stage of long-stroke, high-speed and ultra-precision applications. Motion of the piezo-electric nut ballscrew drive system consists of a high-speed coarse positioning and an ultra-fine positioning. Coarse positioning is done by

J. S Chen; I. C Dwang

2000-01-01

129

Electro-Thermomigration as an Electrical Overstress Failure Mechanism.  

National Technical Information Service (NTIS)

A critical review of electro-thermomigration as an EOS/ESD failure mechanism is presented. The paper focuses on the physical basis of the failure mechanism, the strength of the driving forces, and the effects of pulse attributes such as polarity on electr...

D. G. Pierce

1985-01-01

130

Controllability and diagnosis in electric power systems  

Microsoft Academic Search

While modern electric power systems are often operated under stressed conditions, there is an increasing social demand for reliable electricity supplies. The reliable operation of a power system depends on the power system's ability to maintain a normal operating condition following a disturbance. This study focuses on two aspects of power systems: Controllability and diagnosis, both concerned with the power

Mingguo Hong

1998-01-01

131

Power electronics system integration for electric and hybrid vehicles  

Microsoft Academic Search

The paper gives an overview of the basic requirements, concepts, and trends regarding a system integration of power electronics in hybrid (HEV) and electric vehicles (EV). A site-of-action system integration of the various power electronics subsystems minimizes costs and construction space requirements. New technologies that foster a system integration of power electronics and a merging with the mechanical environment are

Martin März; Andreas Schletz; Bernd Eckardt; Sven Egelkraut; Hubert Rauh

2010-01-01

132

The effects of titania on selected electrical and mechanical properties of hafnia-rich mixed oxides in the system hafnia-zirconia-titania  

SciTech Connect

A study of the effects of titania on selected properties of hafnia-rich mixed oxides in the system hafnia-zirconia-titania (HZT) was made in the region 5 to 20 mol% titania. The effects of titania on the properties were studied for the reduced state as well as the oxidized state of the sintered mixed oxides. The grains of all samples were nominally 1{mu}m. Microcracking regions varying from 16 to 3000 {mu}m were also observed in the microstructures. The electrical conductivity increased with temperature to approximately 10{sup {minus}1} mhos/cm at 1700{degrees}C for all compositions. The thermal expansion coefficient decreased with increasing titania as did the monoclinic to tetragonal transformation temperature. The fracture strength of the oxidized bars tended to decrease with the addition of titania owing to the presence of the second-phase titanate. The fracture strengths of the reduced bars exhibited a minimum corresponding to a two-phase region of monoclinic and cubic phases.

Staszak, P.R.

1988-01-01

133

STEP mechanical systems  

NASA Technical Reports Server (NTRS)

The key elements in the STEP system are depicted including the Spacelab pallet, a modular interface structure, and pallet mounted electronics. Several concepts for potential experiments are illustrated.

Bradley, O. H., Jr.

1984-01-01

134

Eigenanalysis of large electric power systems.  

National Technical Information Service (NTIS)

Modern electric power systems are large and complicated, and in many regions, the generation and transmission systems are operating near their limits. Eigenanalysis is one of the tools used to analyze the behavior of these systems. The primary objectives ...

D. M. Elwood

1991-01-01

135

Nuclear electric propulsion reactor control systems status  

NASA Technical Reports Server (NTRS)

The thermionic reactor control system design studies conducted over the past several years for a nuclear electric propulsion system are described and summarized. The relevant reactor control system studies are discussed in qualitative terms, pointing out the significant advantages and disadvantages including the impact that the various control systems would have on the nuclear electric propulsion system design. A recommendation for the reference control system is made, and a program for future work leading to an engineering model is described.

Ferg, D. A.

1973-01-01

136

Application of fracture mechanics in electrical/mechanical failures of dielectrics  

NASA Astrophysics Data System (ADS)

Theoretical and experimental study of the mechanical/electrical fracture behavior of dielectric materials, piezoelectric ceramics PZT 8, PZT 4, and polymeric material poly vinyl chloride (PVC), was made in this work. The charge-free zone (CFZ) model proposed by Zhang et al. for the failure of conductive cracks in dielectrics, which was well verified by the experimental results of depoled piezoelectric ceramics PZT 4, was extended to predict the failure behavior of conductive cracks in piezoelectric ceramics. Piezoelectric ceramics were treated as mechanically brittle and electrically ductile materials in the charge-free zone model. The failure criterion, developed from the CFZ model, for conductive cracks in piezoelectric ceramics under mechanical and/or electrical loading has an elliptic shape in terms of the normalized electric intensity factor and the normalized stress intensity factor. To verify the theoretical prediction from the CFZ model for piezoelectric ceramics, experiment was conducted to study the failure behavior of electrically conductive cracks (deep notches) in poled lead zirconate titanate PZT-8 ceramics. When the critical stress intensity factor was normalized by the critical stress intensity factor under purely mechanical loading and the critical electric intensity factor was normalized by the critical electric intensity factor under purely electric loading, the experimental results revealed that the failure behavior of the conductive cracks in the ceramics was described by an elliptic function of the normalized electric intensity factor versus the normalized stress intensity factor under combined mechanical and electric loading. The experimental results verified well the theoretical predictions from the CFZ model. The relationship between strain (deformation) and electric field (voltage) is linear when electric fled (voltage) is low. The relationship becomes nonlinear at high electric field (voltage). In order to adopt the linear constitutive equations which have simple forms, and to cover the actual applying procedure at the same time, a novel concept of secant piezoelectric constant was introduced to refine the CFZ model. In addition, the concepts of fracture mechanics, which were successfully applied in the study of poled PZT 4, PZT 8 and depoled PZT 4, were introduced to study the electrical failure behavior of polymeric material poly vinyl chloride (PVC). Two kinds of samples, compact tensile (CT) samples and the double notched samples, were used to obtain the electrical fracture toughnesses. The electrical fracture toughnesses obtained from CT samples were higher than those obtained from the double notched samples. This showed that for polymers, electrical fracture toughnesses were not only related to the tested materials, but also related to the conditions of how the notch tips were electrically biased.

Liu, Guoning

137

Mecomtronics Module D: Electrical and Mechanical Principles  

NSDL National Science Digital Library

Initially developed by NJCATE and a team of math, science, communications and technology faculty, this learning module employs the NJCATE Integrated Curriculum Model to integrate core and technical material. Accessing just-in-time learning concepts in which instructors function as coach/facilitators, the module guides students through core and technical activities built around a main project. Module activities present students with hands-on situations which simulate the workplace both in terms of the knowledge and skills required as well as the ethical concerns they will inevitably address. Specifically, Module D's Filling Station project focuses on process control and production. Students will learn about power supply, sensors, solenoid valves and interfaces, electronic counters, and a sensor interfaces, and will use this knowledge to: Construct, test and verify the operation of the DC power supply Construct and evaluate the performance of the sensors and control system Assemble a liquid filling station Connect the binary counter and seven-segment converter to the digital display Interconnect the system components and verify operation of the filling station according to specifications Prepare and present a project report The filling station will have the capability to: Sense the presence of a container and its contents Fill it with a pre-determined quantity of liquid Count the number of containers filled Display the result Includes student and instructor guides. Target Audience 2-4 year College students Self Evaluation Data: Excellent instructional module to support a new or existing Engineering Technology course or program.

2009-11-27

138

Advanced electrical power system technology for the all electric aircraft  

NASA Technical Reports Server (NTRS)

The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg. Previously announced in STAR as N83-24764

Finke, R. C.; Sundberg, G. R.

1983-01-01

139

Tuning the mechanical behaviour of structural elements by electric fields  

NASA Astrophysics Data System (ADS)

This work reports on the adoption of electric fields to tune the mechanical behaviour of structural elements. A mechanical characterization procedure, consisting of double lap joint and 3-point bending tests, is conducted on copper-polyimide laminates while applying electric fields of varying intensity. Field dependence and, thus, adaptability of shear strength and bending stiffness are shown as a function of the overlapping length and interfaces number, respectively. Further, the impact of remaining charges is investigated in both testing configurations. The findings herein lay the foundation for the implementation of electro-adaptive components in structural applications.

Di Lillo, Luigi; Raither, Wolfram; Bergamini, Andrea; Zündel, Manuel; Ermanni, Paolo

2013-06-01

140

Mechanical Interface for an Electric Propulsion Test Bed.  

National Technical Information Service (NTIS)

As a result of the test bed/MERADCOM dc propulsion system optimization process, two configurations appear to be reasonable choices from a performance standpoint. The fundamental differences lie in the placement of the driver axle and electric propulsion s...

R. W. Blakemore

1979-01-01

141

Dirac Structures and Implicit Lagrangian Systems in Electric Networks  

Microsoft Academic Search

In this paper, we apply Dirac structures and the associated theory of implicit Lagrangian systems to electric networks. We show how a Dirac structure on the flux linkage phase space can be induced from a KCL (Kirchhoff Current Law) constraint distribution on a configuration charge space in analogy with mechanics. In this context, a notion of implicit port-controlled Lagrangian systems

Hiroaki Yoshimura; Jerrold E. Marsden

142

High density printed electrical circuit board card connection system  

Microsoft Academic Search

A zero insertion\\/extraction force printed circuit board card connection system comprises a cam-operated locking mechanism disposed along an edge portion of the printed circuit board. The extrusions along the circuit board mate with an extrusion fixed to the card cage having a plurality of electrical connectors. The card connection system allows the connectors to be held away from the circuit

Baumbaugh; Alan E

1997-01-01

143

Influence of electric power distribution system design on harmonic propagation  

Microsoft Academic Search

The impact of the design parameters of electric power distribution systems on the propagation of harmonic distortion is investigated. This conceptual study is based on simulations on a generalized distribution system model, and leads to an increased insight in the mechanisms of the generation and propagation of voltage distortion. Moreover, analytical expressions are presented that predict the impact of changing

J. A. Ghijselen; W. A. Ryckaert; J. A. Melkebeek

2004-01-01

144

Seismic reliability of electrical power transmission systems  

Microsoft Academic Search

The reliability of electric power transmission systems is important for the probabilistic safety assessment of nuclear power plants under a given earthquake loading as it relates to the loss of off site power to the nuclear power plants. Here, a comprehensive model to evaluate the seismic reliability of electric power transmission systems is presented. The model provides probabilistic assessments of

J. A. Pires; A. H.-S. Ang; R. Villaverde

1996-01-01

145

Safety of high speed guided ground transportation systems: An overview of biological effects and mechanisms relevant to EMF exposures from mass transit and electric rail systems. Final report, October 1991-July 1993  

SciTech Connect

The U.S. has implemented a national initiative to develop maglev (magnetic levitation) and other high-speed rail (HSR) systems. There are concerns for potential adverse health effects of the Extremely Low Frequency (3-3,000 Hz) electric and magnetic fields (EMF) produced by these systems. The Environmental Protection Agency's Office of Radiation Programs is assisting the Federal Railroad Administration address these concerns; this comprehensive review is part of that effort. It outlines magnetic field exposure measurements of the TR07 German maglev system compared with other HSR and conventional systems.

Goldberg, R.B.; Creasey, W.A.; Foster, K.R.

1993-08-01

146

Characteristics of primary electric propulsion systems. [conferences  

NASA Technical Reports Server (NTRS)

The use of advanced electric propulsion systems is expected to provide cost and performance benefits for future energetic space missions. A methodology to predict the characteristics of advanced electric propulsion systems was developed and programmed for computer calculations to allow evaluation of a broad set of technology and mission assumptions. The impact on overall thrust system characteristics was assessed for variations of propellant type, total accelerating voltage, thruster area, specific impulse, and power system approach. The data may be used both to provide direction to technology emphasis and allow for preliminary estimates of electric propulsion system properties for a wide variety of applications.

Byers, D. C.

1979-01-01

147

Energy Saving Electrical Motor Control System.  

National Technical Information Service (NTIS)

An energy saving system in AC electrical motors which provides optimum control of the rriac control voltage supplied to different motors with which the system is used, despite the different characteristics of such motors is described. A three phase motor,...

T. M. Edge

1982-01-01

148

Modeling of multiconverter more electric ship power systems using the generalized state space averaging method  

Microsoft Academic Search

Based on the more electric ship (MES) concept, conventional mechanical, hydraulic, and pneumatic power transfer systems are replaced by electrical systems in different sea vehicles. Considering different levels of power requirements of various electrical loads and for the achievement of compact, light, safe, and efficient power supplies, implementation of multiconverter power electronics based power systems is the most feasible option

Madan M. Jalla; Ali Emadi; Geoffrey A. Williamson; Babak Fahimi

2004-01-01

149

Comparison of Mechanical Properties for Several Electrical Spring Contact Alloys.  

National Technical Information Service (NTIS)

Purpose was to determine whether beryllium--nickel alloy 440 (Ni-1.95 Be-0.5 Ti) had mechanical properties which made it suitable as a substitute for the presently used precious metal contact alloys Paliney 7 and Neyoro G, in certain electrical contact ap...

T. V. Nordstrom

1976-01-01

150

Comparison of mechanical properties for several electrical spring contact alloys  

Microsoft Academic Search

Work was conducted to determine whether beryllium-nickel alloy 440 had mechanical properties which made it suitable as a substitute for the presently used precious metal contact alloys Paliney 7 and Neyoro G, in certain electrical contact applications. Possible areas of applicability for the alloy were where extremely low contact resistance was not necessary or in components encountering elevated temperatures above

Nordstrom

1976-01-01

151

Control Mechanisms for Residential Electricity Demand in SmartGrids  

Microsoft Academic Search

We consider mechanisms to optimize electricity consumption both within a home and across multiple homes in a neighborhood. The homes are assumed to use energy management controllers (EMCs) to control the operation of some of their appliances. EMCs, which are a feature of the emerging SmartGrid, use both prices and user preferences to control power usage across the home. We

Shalinee Kishore; Lawrence V. Snyder

2010-01-01

152

132. WEST SIDE OF MECHANICAL AND ELECTRICAL ROOM (210), LSB ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

132. WEST SIDE OF MECHANICAL AND ELECTRICAL ROOM (210), LSB (BLDG. 751), QUALITY CONTROL BOARD ON LEFT. SOUTH SIDE OF TRANSFORMER ROOM (212) ON RIGHT SIDE OF PHOTOGRAPH, THROUGH OPEN DOORS. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

153

113. VIEW OF NORTH SIDE OF MECHANICAL AND ELECTRICAL ROOM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

113. VIEW OF NORTH SIDE OF MECHANICAL AND ELECTRICAL ROOM (110), LSB (BLDG. 770). QUALITY ASSURANCE ROOM (106A) ON RIGHT SIDE OF PHOTO; CABLE TRAYS OVERHEAD AT TOP; STAIRS TO LSB (BLDG. 770) ADDITION (ROOMS 117 THROUGH 120) IN CENTER OF PHOTO. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

154

Minimum Check List for Mechanical and Electrical Plans & Specifications.  

ERIC Educational Resources Information Center

This is the fifth revision of the Minimum Check List since its origin in 1960 by North Carolina's School Planning. The checklist was developed to serve as a means of communication between school agencies and design professionals and has been widely used in the development and review of mechanical and electrical plans and specifications by…

North Carolina State Dept. of Public Instruction, Raleigh. Div. of School Facility Services.

155

Temperature dependence and mechanism of electrically detected ESR at the nu=1 filling factor of a two-dimensional electron system  

Microsoft Academic Search

Electrically detected electron spin resonance (EDESR) signals were acquired as a function of temperature in the 0.3 4.2 K temperature range in an AlGaAs\\/GaAs multiple-quantum-well sample at the nu=1 filling factor at 5.7 T. In the particular sample studied, the linewidth is approximately temperature independent, while the amplitude exhibits a maximum at about 2 K and vanishes with increased or

Eugene Olshanetsky; Joshua D. Caldwell; Manyam Pilla; Shu-Chen Liu; Clifford R. Bowers; Jerry A. Simmons; John L. Reno

2003-01-01

156

Effect of Ar Ion Beam Pre-Treatment of Poly(ethylene terephthalate) Substrate on the Mechanical and Electrical Stability of Flexible InSnO Films Grown by Roll-to-Roll Sputtering System  

NASA Astrophysics Data System (ADS)

We investigated the effects of Ar ion beam irradiation on a flexible poly(ethylene terephthalate) (PET) substrate as surface pre-treatment method in the roll-to-roll (R2R) sputtering system and its contribution to the electrical durability of flexible InSnO (ITO) electrode upon that the flexible PET substrate under repeated mechanical stresses. It was found that the Ar ion beam irradiation of the flexible PET surface could improve an adhesion between R2R sputter-grown ITO film and the PET substrate. X-ray photoelectron spectroscopy results showed that the Ar ion beam irradiation lead to an increase of hydrophilic functional groups when the working pressure, Ar ion beam power, and exposure time increases. Repetitive bending stresses for the flexible ITO/PET film which fabricated through the surface pre-treatment by Ar ion beam irradiation showed more stable electrical durability than those of ITO films on the wet-cleaned PET substrate due to enhanced interfacial adhesion between the ITO film and PET surface. This suggests that the Ar ion beam pre-treatment before sputtering of ITO film in R2R sputtering system is an effective technique to improve the adhesion between ITO film and PET substrate.

Choi, Kwang-Hyuk; Kim, Han-Ki

2013-10-01

157

Captured key electrical safety lockout system  

DOEpatents

A safety lockout apparatus for an electrical circuit includes an electrical switch, a key, a lock and a blocking mechanism. The electrical switch is movable between an ON position at which the electrical circuit is energized and an OFF position at which the electrical circuit is deactivated. The lock is adapted to receive the key and is rotatable among a plurality of positions by the key. The key is only insertable and removable when the lock is at a preselected position. The lock is maintained in the preselected position when the key is removed from the lock. The blocking mechanism physically maintains the switch in its OFF position when the key is removed from the lock. The blocking mechanism preferably includes a member driven by the lock between a first position at which the electrical switch is movable between its ON and OFF positions and a second position at which the member physically maintains the electrical switch in its OFF position. Advantageously, the driven member's second position corresponds to the preselected position at which the key can be removed from and inserted into the lock.

Darimont, Daniel E. (Aurora, IL)

1995-01-01

158

Fault-tolerant electrical power system  

NASA Astrophysics Data System (ADS)

An electrical system that will meet the requirements of a 1990s two-engine fighter is being developed in the Fault-Tolerant Electrical Power System (FTEPS) program, sponsored by the AFWAL Aero Propulsion Laboratory. FTEPS will demonstrate the generation and distribution of fault-tolerant, reliable, electrical power required for future aircraft. The system incorporates MIL-STD-1750A digital processors and MIL-STD-1553B data buses for control and communications. Electrical power is distributed through electrical load management centers by means of solid-state power controllers for fault protection and individual load control. The system will provide uninterruptible power to flight-critical loads such as the flight control and mission computers with sealed lead-acid batteries. Primary power is provided by four 60 kVA variable speed constant frequency generators. Buildup and testing of the FTEPS demonstrator is expected to be complete by May 1988.

Mehdi, Ishaque S.; Weimer, Joseph A.

1987-10-01

159

How Do We Convert Electrical Energy into Mechanical Energy?  

NSDL National Science Digital Library

In this activity, learners make an electromagnet motor to demonstrate the most basic method of changing electrical energy into mechanical energy. This experiment relates to Nikola Tesla's work in electrical engineering and his invention of the AC (alternating current) induction motor. To provide learners with background about Tesla, this lesson guide suggests learners watch clips from the film "Tesla: Master of Lightning" and write a report about the challenges Tesla faced as an inventor. Use this activity to help learners explore the Law of Conservation of Energy, motors, and electromagnets.

Hardesty, Jim; Hardesty, Judy

2013-07-30

160

BACTERICIDAL ELECTRICALLY ENHANCED FILTRATION SYSTEM FOR CLEANROOMS  

Microsoft Academic Search

An ionizing electrically enhanced filter (EEF) for clean rooms is described. The electrical enhancement process results in a) increased filtration efficiency at lower pressure drop and b) bactericidal effects. The EEF system enables higher flow, lower weight and smaller package filters, as compared to Fan Filter Units (FFUs). The bactericidal effect has been demonstrated using Staphylococcus epidermidis. Almost all the

Rajan Jaisinghani; Thomas Inzana; Gretchen Glindemann

161

Sharing frequency response between asynchronous electrical systems  

Microsoft Academic Search

Since the electricity industry unbundling, frequency control has became a service. It is mainly provided by synchronous generators connected to the transmission grid. Nevertheless, other synchronous entities (electric systems and offshore wind farms), which are not synchronously linked to the main interconnection, could technically contribute to the frequency control. Their participation is conditioned by appropriate HVDC substations capabilities. This paper

S. Sterpu; M. Nguyen Tuan

2009-01-01

162

Metrology system for pulsed electric fields processing  

Microsoft Academic Search

Efficient process monitoring and accurate measurement of the electrical parameters defining pulsed electric fields (PEF) treatment and lethality are key factors in the implementation of PEF. A metrology system that can accurately evaluate and record treatment delivery was developed. To achieve this end one current sensor and two high voltage sensors were placed in a food PEF coaxial treatment chamber,

M. M Góngora-Nieto; F Younce; G. M Hyde; P. D Pedrow; B. G Swanson; G. V Barbosa-Cánovas

2002-01-01

163

Survey of aircraft electrical power systems  

NASA Technical Reports Server (NTRS)

Areas investigated include: (1) load analysis; (2) power distribution, conversion techniques and generation; (3) design criteria and performance capabilities of hydraulic and pneumatic systems; (4) system control and protection methods; (5) component and heat transfer systems cooling; and (6) electrical system reliability.

Lee, C. H.; Brandner, J. J.

1972-01-01

164

Mine Hoist Electrical Systems Study. Volume 1. Mine Hoist Electrical Systems Inspection Manual.  

National Technical Information Service (NTIS)

The manual describes how to inspect and maintain mine hoist electrical systems. It includes daily, weekly, monthly, and annual checklists. Federal regulations pertaining to electrical inspection are reviewed. Inspection and maintenance of hoist drives, sw...

J. D. Cooper R. H. King

1985-01-01

165

High density printed electrical circuit board card connection system  

DOEpatents

A zero insertion/extraction force printed circuit board card connection system comprises a cam-operated locking mechanism disposed along an edge portion of the printed circuit board. The extrusions along the circuit board mate with an extrusion fixed to the card cage having a plurality of electrical connectors. The card connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned. The card connection system provides a simple solution to the need for a greater number of electrical signal connections. 12 figs.

Baumbaugh, A.E.

1997-05-06

166

High density printed electrical circuit board card connection system  

DOEpatents

A zero insertion/extraction force printed circuit board card connection system comprises a cam-operated locking mechanism disposed along an edge portion of the printed circuit board. The extrusions along the circuit board mate with an extrusion fixed to the card cage having a plurality of electrical connectors. The card connection system allows the connectors to be held away from the circuit board during insertion/extraction and provides a constant mating force once the circuit board is positioned. The card connection system provides a simple solution to the need for a greater number of electrical signal connections.

Baumbaugh, Alan E. (Aurora, IL)

1997-01-01

167

Bus bar electrical feedthrough for electrorefiner system  

DOEpatents

A bus bar electrical feedthrough for an electrorefiner system may include a retaining plate, electrical isolator, and/or contact block. The retaining plate may include a central opening. The electrical isolator may include a top portion, a base portion, and a slot extending through the top and base portions. The top portion of the electrical isolator may be configured to extend through the central opening of the retaining plate. The contact block may include an upper section, a lower section, and a ridge separating the upper and lower sections. The upper section of the contact block may be configured to extend through the slot of the electrical isolator and the central opening of the retaining plate. Accordingly, relatively high electrical currents may be transferred into a glovebox or hot-cell facility at a relatively low cost and higher amperage capacity without sacrificing atmosphere integrity.

Williamson, Mark; Wiedmeyer, Stanley G; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

2013-12-03

168

Electrical Characteristics of Epoxy\\/nanoclay Nanodielectric Systems  

Microsoft Academic Search

The field of nanocomposites is a rapidly growing area of interest as more and more materials appear with exciting properties and novel applications. Nanocomposites based on clay systems have been widely investigated, where they have been shown to exhibit improved mechanical, thermal, optical and physicochemical properties. It is therefore of no surprise that the electrical properties of such nanocomposites are

T. N. Matheson; A. S. Vaughan; S. J. Sutton; A. Minigher

2007-01-01

169

The AC Propulsion System for an Electric Vehicle, Phase 1.  

National Technical Information Service (NTIS)

A functional prototype of an electric vehicle ac propulsion system was built consisting of a 18.65 kW rated ac induction traction motor, pulse width modulated (PWM) transistorized inverter, two speed mechanically shifted automatic transmission, and an ove...

S. Geppert

1981-01-01

170

Electrical Appliance Energy Consumption Control Methods and Electrical Energy Consumption Systems.  

National Technical Information Service (NTIS)

Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distr...

D. P. Chassin D. W. Winiarski J. E. Dagle M. Kinter-Meyer M. K. Donnelly

2005-01-01

171

Neurophysiological and biophysical evidence on the mechanism of electric taste  

PubMed Central

The phenomenon of electric taste was investigated by recording from the chorda tympani nerve of the rat in response to both electrical and chemical stimulations of the tongue with electrolytes in order to gain some insight into its mechanism on both a neurophysiological and biophysical basis. The maximum neural response levels were identical for an individual salt (LiCl, NaCl, KCl, or CaCl2), whether it was presented as a chemical solution or as an anodal stimulus through a subthreshold solution. These observations support the idea that stimulation occurs by iontophoresis of ions to the receptors at these current densities (less than 100 microA/cm2). Electric responses through dilute HCl were smaller than the chemically applied stimulations, but the integrated anodal responses appeared similar to chemical acid responses, as evidenced by an OFF response to both forms of stimuli. Hydrogen may be more permeant to the lingual epithelium and would thus be shunted away from the taste receptors during anodal stimulation. When the anion of electric taste was varied via subthreshold salt solutions, the response magnitude increased as the mobility of the anion decreased. The transport numbers of the salts involved adequately explains these differences. The physical aspects of ion migration occurring within the adapting fluid on the tongue are also discussed. Direct neural stimulation by the current appears to occur only at higher current densities (greater than 300 microA/cm2). If the taste cells of the tongue were inactivated with either iodoacetic acid (IAA) or N-ethyl maleimide (NEM), or removed with collagenase, then responses from the chorda tympani could be obtained only at these higher current densities. Latency measurements before and after IAA or NEM treatment corroborated these findings. The results are discussed in terms of several proposed mechanisms of electric taste and it is concluded that an ion accumulation mechanism can adequately explain the data.

1985-01-01

172

Direct current electrical controls for heating systems  

US Patent & Trademark Office Database

A method and apparatus for controlling the normal operation of a hydronic heating system, (including AC powered, gas-burning hot water boiler, multi-zone systems) using a DC power source, such as battery power, as the primary continuous source of electricity. Control functions minimize the consumption of electric power during normal operation, and eliminate standby electric consumption in order to extend the life of the batteries and maximize the run-time of the heating system. A DC to DC converter supplies low voltage DC power to the zone thermostats, and also supplies the proper voltage through zone relays to operate DC zone pumps. By allowing the use of DC power for the thermostats and zone pumps, the system eliminates the need for transformers, zone valves, and AC circulators, resulting in a large savings in electrical consumption and the elimination of the standby electric demand ("phantom load") common in conventional hydronic heating systems. A DC to AC inverter is dedicated to supply AC power for a hydronic (hot water) boiler. The inverter is switched on by relays only when needed, thereby eliminating the "phantom electric load" consumed by most boilers when standing by. A time delay relay circuit allows the boiler to go through its proper shutdown sequence before power is removed. This control system does not require any internal modification to the other heating system components.

2001-05-29

173

Electrical and Mechanical Characteristics of Epoxy-Nanoclay Composite  

NASA Astrophysics Data System (ADS)

In this study, we investigated the effects of nanoclay additives on the electrical and mechanical properties of diglycidyl ether of bisphenol A (DGEBA) epoxy resin. Epoxy-clay nanocomposites were synthesized using organically modified two montmorillonite clays (MMT) with different interlamellar spacing (31.5 Å and 18.5 Å). The electrical and mechanical properties of epoxy-clay nanocopomosites were measured with variation of the amount and type of clay. The nanocomposites were found to be homogenous materials although the nanocomposites still have clay aggregates with increasing nanoclay contents. The dielectric constant showed between 3.2 ~ 3.5 and the dielectric loss showed between 3.2 ~ 5.7% in all nanocoposites. The dielectric strength and tensile strength of the 5 wt% Cloisite 15A added epoxy-oclay nanocomposite were 23.9 kV/mm and 86.7 MPa, respectively.

Noh, Hyun-Ji; Nam, Sung-Pill; Lee, Sung-Gap; Ahn, Byeong-Lib; Won, Woo-Sik; Woo, Hyoung-Gwan; Park, Sang-Man

174

Modular Solar Electric Power (MSEP) Systems (Presentation)  

SciTech Connect

This presentation discusses the development and deployment of Modular Solar Electric Power (MSEP) systems, the feasibility of application of existing binary power cycles to solar trough technology, and identification of next action items.

Hassani, V.

2000-06-18

175

Curriculum for Electric Motor Systems Technician  

NSDL National Science Digital Library

This pdf document from The British Columbia Industry Training Authority describes what is involved in the electric motor system technician (winder electrician) program. The profile includes curriculum description, required hours and assessment methods.

2010-05-13

176

A mechanically and electrically self-healing supercapacitor.  

PubMed

The first mechanically and electrically self-healing supercapacitor has been successfully fabricated. It exhibits excellent self-healing performance with the restoration of the specific capacitance up to 85.7% of its original value even after the 5(th) mechanical cutting. This achievement may provide a way to expand the lifetime of future energy storage devices and endow them with desirable economic and human safety attributes, as well as promote the development of next-generation self-healing electronics. PMID:24554600

Wang, Hua; Zhu, Bowen; Jiang, Wencao; Yang, Yun; Leow, Wan Ru; Wang, Hong; Chen, Xiaodong

2014-06-01

177

Mass transportation mechanism in electric-biased carbon nanotubes.  

PubMed

The mass transportation mechanism in electric-biased carbon nanotubes (CNTs) is investigated experimentally. Except for the widely accepted electromigration mechanism, we find out the thermal effect can also induce the mass transportation in the form of thermomigration or thermal evaporation. Moreover, the convincing in situ transmission electron microscope experiment results show the thermal gradient force overrides the electromigration force in most conditions, according to specific parameters of the CNTs and "cargos". A full analysis on the thermal gradient force and electromigration force imposed on the cargos is given, thus our experimental results are well explained and understood. PMID:20957981

Zhao, Jiong; Huang, Jia-Qi; Wei, Fei; Zhu, Jing

2010-11-10

178

SITE ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

SciTech Connect

The Site Electrical Power System receives and distributes utility power to all North Portal site users. The major North Portal users are the Protected Area including the subsurface facility and Balance of Plant areas. The system is remotely monitored and controlled from the Surface Operations Monitoring and Control System. The system monitors power quality and provides the capability to transfer between Off-Site Utility and standby power (including dedicated safeguards and security power). Standby power is only distributed to selected loads for personnel safety and essential operations. Security power is only distributed to essential security operations. The standby safeguards and security power is independent from all other site power. The system also provides surface lighting, grounding grid, and lightning protection for the North Portal. The system distributes power during construction, operation, caretaker, and closure phases of the repository. The system consists of substation equipment (disconnect switches, breakers, transformers and grounding equipment) and power distribution cabling from substation to the north portal switch gear building. Additionally, the system includes subsurface facility substation (located on surface), switch-gear, standby diesel generators, underground duct banks, power cables and conduits, switch-gear building and associated distribution equipment for power distribution. Each area substation distributes power to the electrical loads and includes the site grounding, site lighting and lightning protection equipment. The site electrical power system distributes power of sufficient quantity and quality to meet users demands. The Site Electrical Power System interfaces with the North Portal surface systems requiring electrical power. The system interfaces with the Subsurface Electrical Distribution System which will supply power to the underground facilities from the North Portal. Power required for the South Portal and development side activities of the subsurface facility will be provided at the South Portal by the Subsurface Electrical Distribution System. The Site Electrical Power System interfaces with the Off-Site Utility System for the receipt of power. The System interfaces with the Surface Operations Monitoring and Control System for monitoring and control. The System interfaces with MGR Site Layout System for the physical location of equipment and power distribution.

E.P. McCann

1999-04-16

179

Harmony Search Applications in Mechanical, Chemical and Electrical Engineering  

Microsoft Academic Search

The primary aim of this chapter is to introduce the state of the art applications of the harmony search (HS) algorithm in\\u000a mechanical, chemical and electrical engineering fields. The HS algorithm has been broadly utilized in complex optimization\\u000a problems arising in most engineering applications. It has been reported to be a viable alternative to other conventional optimization\\u000a techniques in these

Mohammad Fesanghary

180

Solar electric propulsion systems - A survey  

Microsoft Academic Search

The Solar Electric Propulsion System (SEPS) currently under development in the United States offers several advantages as a third-stage power system for interplanetary and inter-earth-orbit flights. Its electric propulsion motors (EPM), with the relatively large specific impulse of 30,000 m\\/sec each, consume less propellant than do chemical rocket motors or compressed-gas engines, and constitute, with the solar batteries, 50% of

V. A. Grilikhes; G. M. Zavialova; L. B. Popov

1980-01-01

181

Chemical Fume Hoods in Higher Education Science Laboratories: Electrical, Mechanical and Human Controls.  

ERIC Educational Resources Information Center

This paper is predicated on the realization that a chemical hood is only one element of laboratory safety which encompasses a variety of other elements starting with the architectural design and layout of laboratories; through the installation, operation and maintenance of integrated electrical and mechanical systems; to the safety-mindedness of…

Casey, John M.

182

General method for calculating polarization electric fields produced by auroral Cowling mechanism and application examples  

NASA Astrophysics Data System (ADS)

The Cowling mechanism is characterized by the generation of polarization space charges in the ionosphere in consequence of a partial or total blockage of FAC flowing between the ionosphere and the magnetosphere. Thus a secondary polarization electric field builds up in the ionosphere, which guarantees that the whole (primary + secondary) ionospheric current system is again in balance with the FAC. In the Earth's ionosphere the Cowling mechanism is long known to operate in the equatorial electrojet, and several studies indicate that it is important also in auroral current systems. We present a general method for calculate the secondary polarization electric field, when the ionospheric conductances, the primary (modeled) or the total (measured) electric field, and the Cowling efficiency are given. Here the Cowling efficiency is defined as the fraction of the divergent Hall current canceled by secondary Pedersen current. In contrast to previous studies, our approach is a general solution which is not limited to specific geometrical setups (like an auroral arc), and all parameters may have any kind of spatial dependence. The solution technique is based on spherical elementary current (vector) systems (SECS). This way, we avoid the need to specify explicit boundary conditions for the searched polarization electric field or its potential, which would be required if the problem was solved in a differential equation approach. Instead, we solve an algebraic matrix equation, for which the implicit boundary condition that the divergence of the polarization electric field vanishes outside our analysis area is sufficient. In order to illustrate the effect of Cowling mechanism on ionospheric current systems, we apply our method to two simple models of auroral electrodynamic situations: 1) a mesoscale strong conductance enhancement in the early morning sector within a relatively weak southward primary electric field, 2) a morning sector auroral arc with only a weak conductance enhancement, but a large southward primary electric field at the poleward flank of the arc. While the significance of the polarization electric field for maximum Cowling efficiency is large for the first case, it is rather minor for the second one. Both models show that the Cowling effect may not only change the magnitude of the current systems, but also their overall geometry. Further, the polarization electric field may extend into regions where the primary electric field is small, thus even dominating the total electric field in these regions. For the first model case, the total Joule heating integrated over the analysis area decreases by a factor of about 4 for maximum Cowling efficiency as compared to the case of vanishing Cowling efficiency. Further, for this case the resulting total electric field structurally shows a strong resemblance to that frequently observed during auroral omega band events.

Vanhamäki, Heikki; Amm, Olaf; Fujii, Ryo; Yoshikawa, Aki; Ieda, Aki

2013-04-01

183

Construction LAN System for Electrical Substation.  

National Technical Information Service (NTIS)

In this paper, the authors propose an optical-fiber-type LAN system for electrical substations. This system uses nodes arranged in each line to take field data for protection and control and employs a token-ring transmission system to transmit such data. ...

M. Kurono H. Kameda A. Tsuboi

1988-01-01

184

Specialized battery emulator for automotive electrical systems  

Microsoft Academic Search

Complexity of the automotive electrical power system is continuously increasing. Greater amount of higher loads is added and active energy management is being introduced. The whole design of such power systems depends on the batteries being used. Since safety-related systems also need power to function, special care has to be taken considering voltage quality. However, there are a lot of

T. Baumho?fer; W. Waag; D. U. Sauer

2010-01-01

185

Metroliner Auxiliary Power Electrical System Reliability Study.  

National Technical Information Service (NTIS)

The reliability of the electrical system of any vehicle is greatly affected by the way the system is configured. The propulsion and braking systems of a train must be unaffected by failures occurring in the nonessential power areas. With these criteria in...

J. D. Abbas C. W. Watt

1971-01-01

186

Electrical aspects of photovoltaic-system simulation  

NASA Astrophysics Data System (ADS)

A TRNSYS simulation was developed to simulate the performance of utility interactive residential photovoltaic energy systems. The PV system is divided into major functional components, which are individually described with computer models. The results of simulation and actual measured data are compared. The electrical influences on the design of such photovoltaic energy systems are given particular attention.

Hart, G. W.; Raghuraman, P.

1982-06-01

187

Dynamic security assessment in electric power systems  

Microsoft Academic Search

A new approach to dynamic security assessment in electric power systems is proposed. A power system is modeled as a dynamical system with random variable structure. Structural variations are caused by primary and secondary events. Primary events are state-independent disturbances representing line and unit faults and load changes and are modeled by random jump processes. Secondary events that represent forced

Maghsoodlou

1983-01-01

188

Intelligent tutoring system for electric circuit exercising  

Microsoft Academic Search

An intelligent tutoring system called Circuit Exerciser is described. The system is designed to help university students learn more about electric circuits. It can formulate drill problems, solve them, and infer mistakes in a student's answer. It can also provide helpful comments to the students on how the mistake was made. The system shows the circuit of the presented problem

Atsushi Yoshikawa; Masafumi Shintani; Yujiro Ohba

1992-01-01

189

Study of advanced electric propulsion system concept using a flywheel for electric vehicles  

NASA Technical Reports Server (NTRS)

Advanced electric propulsion system concepts with flywheels for electric vehicles are evaluated and it is predicted that advanced systems can provide considerable performance improvement over existing electric propulsion systems with little or no cost penalty. Using components specifically designed for an integrated electric propulsion system avoids the compromises that frequently lead to a loss of efficiency and to inefficient utilization of space and weight. A propulsion system using a flywheel power energy storage device can provide excellent acceleration under adverse conditions of battery degradation due either to very low temperatures or high degrees of discharge. Both electrical and mechanical means of transfer of energy to and from the flywheel appear attractive; however, development work is required to establish the safe limits of speed and energy storage for advanced flywheel designs and to achieve the optimum efficiency of energy transfer. Brushless traction motor designs using either electronic commutation schemes or dc-to-ac inverters appear to provide a practical approach to a mass producible motor, with excellent efficiency and light weight. No comparisons were made with advanced system concepts which do not incorporate a flywheel.

Younger, F. C.; Lackner, H.

1979-01-01

190

System performance predictions for Space Station Freedom's electric power system  

NASA Technical Reports Server (NTRS)

Space Station Freedom Electric Power System (EPS) capability to effectively deliver power to housekeeping and user loads continues to strongly influence Freedom's design and planned approaches for assembly and operations. The EPS design consists of silicon photovoltaic (PV) arrays, nickel-hydrogen batteries, and direct current power management and distribution hardware and cabling. To properly characterize the inherent EPS design capability, detailed system performance analyses must be performed for early stages as well as for the fully assembled station up to 15 years after beginning of life. Such analyses were repeatedly performed using the FORTRAN code SPACE (Station Power Analysis for Capability Evaluation) developed at the NASA Lewis Research Center over a 10-year period. SPACE combines orbital mechanics routines, station orientation/pointing routines, PV array and battery performance models, and a distribution system load-flow analysis to predict EPS performance. Time-dependent, performance degradation, low earth orbit environmental interactions, and EPS architecture build-up are incorporated in SPACE. Results from two typical SPACE analytical cases are presented: (1) an electric load driven case and (2) a maximum EPS capability case.

Kerslake, Thomas W.; Hojnicki, Jeffrey S.; Green, Robert D.; Follo, Jeffrey C.

1993-01-01

191

Micro electromechanical systems (MEMS) for mechanical engineers  

SciTech Connect

The ongoing advances in Microelectromechanical Systems (MEMS) are providing man-kind the freedom to travel to dimensional spaces never before conceivable. Advances include new fabrication processes, new materials, tailored modeling tools, new fabrication machines, systems integration, and more detailed studies of physics and surface chemistry as applied to the micro scale. In the ten years since its inauguration, MEMS technology is penetrating industries of automobile, healthcare, biotechnology, sports/entertainment, measurement systems, data storage, photonics/optics, computer, aerospace, precision instruments/robotics, and environment monitoring. It is projected that by the turn of the century, MEMS will impact every individual in the industrial world, totaling sales up to $14 billion (source: System Planning Corp.). MEMS programs in major universities have spawned up all over the United States, preparing the brain-power and expertise for the next wave of MEMS breakthroughs. It should be pointed out that although MEMS has been initiated by electrical engineering researchers through the involvement of IC fabrication techniques, today it has evolved such that it requires a totally multi-disciplinary team to develop useful devices. Mechanical engineers are especially crucial to the success of MEMS development, since 90% of the physical realm involved is mechanical. Mechanical engineers are needed for the design of MEMS, the analysis of the mechanical system, the design of testing apparatus, the implementation of analytical tools, and the packaging process. Every single aspect of mechanical engineering is being utilized in the MEMS field today, however, the impact could be more substantial if more mechanical engineers are involved in the systems level designing. In this paper, an attempt is made to create the pathways for a mechanical engineer to enter in the MEMS field. Examples of application in optics and medical devices will be used to illustrate how mechanical engineers made impact. Through a basic understanding of the history of MEMS, the background physics and scaling in micromechanical systems, and an introduction to baseline MEMS processes, a mechanical engineer should be well on his way to Alice's wonderland in the ever-exciting playground of MEMS.

Lee, A. P., LLNL

1996-11-18

192

Electric arc-fired blast furnace system  

SciTech Connect

This invention relates to an electric-arc fired blast furnace system for the reduction of iron-bearing material utilizing electric-arc heated air containing a reducing gas or carbon-containing fuel allowing for a decrease in the amount of coke normally used in the reduction process. The excess reducing gases exiting the furnace are utilized as a source of power via a system consisting of turbines, compressors and a heat exchanger to drive the electrical generators which are used to provide electricity to the arc heaters. This arrangement forms an essentially closed loop furnace system for metal reduction. Injection of finely-divided coal into the arc-heated air to provide reductants is also employed.

Fey, M. G.

1985-04-02

193

29 CFR 1910.302 - Electric utilization systems.  

Code of Federal Regulations, 2013 CFR

...Systems § 1910.302 Electric utilization systems...safety standards for electric utilization systems... (v) Recreational vehicles; (vi) Industrial...homes and recreational vehicles; (ii) Installations...exclusive control of electric utilities for...

2013-07-01

194

14 CFR 23.1359 - Electrical system fire protection.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 2009-01-01 false Electrical system fire protection. 23.1359 ...COMMUTER CATEGORY AIRPLANES Equipment Electrical Systems and Equipment § 23.1359 Electrical system fire protection. (a) Each...

2009-01-01

195

14 CFR 23.1359 - Electrical system fire protection.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Electrical system fire protection. 23.1359 ...COMMUTER CATEGORY AIRPLANES Equipment Electrical Systems and Equipment § 23.1359 Electrical system fire protection. (a) Each...

2010-01-01

196

A Rotative Electrical Impedance Tomography Reconstruction System  

NASA Astrophysics Data System (ADS)

Electrical impedance tomography (EIT) is a powerful tool for mapping the conductivity distribution of estimated objects. The EIT system is entirely implemented by electrical technique, so it is a relatively cheap system and data can be collected very rapidly. But it has few commercially medical EIT systems available. This is because impedance image unable to achieve the essential spatial resolution and this technique has an intrinsically poor signal to noise ratio. In this paper, we have developed a high performance rotative EIT system (REIT) for expanding the independent measurements. By rotate the electrodes successive, REIT could change the position of electrodes and acquire more measurement data. This rotative measurement method not only can increase the resolution of impedance images, but also reduce the complexity of measurement system. We hope the improvement of REIT will bring some help in electrical impedance tomography.

Yu, Fang-Ming; Huang, Chen-Ning; Chang, Fang-Wei; Chung, Hung-Yuan

2006-10-01

197

Catalog of Components for Electric and Hybrid Vehicle Propulsion Systems.  

National Technical Information Service (NTIS)

Design and performance specifications are presented for electrical, hydraulic, mechanical, instrumentation, heat exchanger, space conditioning and control equipment which can be used in electric or hybrid-electric vehicles. The components listed in this c...

H. C. Eissler

1981-01-01

198

A satellite communications system for electric utilities  

NASA Technical Reports Server (NTRS)

This paper presents the results of a study into the feasibility of using satellite communications for a country-wide system of electric distribution system monitoring and control. The concept selected for study involves the use of a geostationary satellite with a large multi-beam antenna to provide a major part of the communications and control network between participating utilities and various elements of their power distribution networks, including customer loads. Electric utility communications requirements are projected through 1995 in order to size the required capacity of the system. Two basic systems are examined: a one-way system for load control, and a two-way system for distribution system monitoring and control, including customer meter reading. An operating protocol is proposed for each system. Preliminary cost estimates are identified element by element. Finally, expansion of the basic system to include a set of ancillary communications functions is briefly discussed.

Vaisnys, A.; Bergen, L.

1980-01-01

199

Perception of electrical and mechanical stimulation of the skin: implications for electrotactile feedback  

NASA Astrophysics Data System (ADS)

Spinal cord injury is often accompanied by impaired tactile and proprioceptive sensations. Normally, somatosensensory information derived from such sensations is important in the formation of voluntary motor commands. Therefore, as a preliminary step toward the development of an electrotactile feedback system to restore somatosensation, psychophysical methods were used to characterize perceptual attributes associated with electrical stimulation of the skin on the back of the neck in human subjects. These data were compared to mechanical stimulation of the skin on the back of neck and on the distal pad of the index finger. Spatial acuity of the neck, evaluated using two-point thresholds, was not significantly different for electrical (37 ± 14 mm) or mechanical stimulation (39 ± 10 mm). The exponent (?) of the best fitting power function relating perceived intensity to applied stimulus strength was used to characterize perceptual sensitivity to mechanical and electrical stimuli. For electrical stimuli, both current amplitude-modulated and frequency-modulated trains of pulses were tested. Perceptual sensitivity was significantly greater for current amplitude modulation (? = 1.14 ± 0.37) compared to frequency modulation (? = 0.57 ± 0.24) and mechanical stimulation (0.51 ± 0.12). Finally, based on the data gathered here, we derive a transfer function that could be used in the future to convert mechanical stimuli detected with artificial sensors placed on the fingers into electrotactile signals that evoke perceptions similar to those arising from normal mechanical stimulation of the skin.

Marcus, Patrick L.; Fuglevand, Andrew J.

2009-12-01

200

The Dynamic Balancer electrical safety systems  

SciTech Connect

The Pantex Plant Dynamic Balancer is used to identify physical imbalance in some weapon systems. This study was conducted at the request of the US Department of Energy/Albuquerque Operations Office (USDOE/AL) Dynamic Balancer Project Team to identify the electrical conditions required for motor over-speed to occur and to discuss the functions of the various electrical protective features associated with the Dynamic Balancer (DB). As is shown through the development of a fault tree, numerous electrical and human failures are required for over-speed conditions to occur. As directed by the Project Team, no effort was made to develop detailed fault trees for all electrical systems, to quantify basic events in the fault tree, or to develop accident scenarios leading to or resulting from over-speed. The Pantex Building 12-60, Bay 2, facility electrical circuits and grounding are described, and potential hazards are discussed. DB motor over-speed is a safety concern, and therefore, the controls that limit this condition are described and discussed in detail. Other safety-significant electrical circuits are discussed as well. These safety systems also are described in the facility Basis for Interim Operation. A potential for a motor over-speed that is not sensed by the standard safety protective systems does exist. This fault pathway is discussed, and recommendations to mitigate its effect are made.

Konkel, H.

1997-12-01

201

Advanced electric propulsion system concept for electric vehicles  

NASA Technical Reports Server (NTRS)

Seventeen propulsion system concepts for electric vehicles were compared to determine the differences in components and battery pack to achieve the basic performance level. Design tradeoffs were made for selected configurations to find the optimum component characteristics required to meet all performance goals. The anticipated performance when using nickel-zinc batteries rather than the standard lead-acid batteries was also evaluated. The two systems selected for the final conceptual design studies included a system with a flywheel energy storage unit and a basic system that did not have a flywheel. The flywheel system meets the range requirement with either lead-acid or nickel-zinc batteries and also the acceleration of zero to 89 km/hr in 15 s. The basic system can also meet the required performance with a fully charged battery, but, when the battery approaches 20 to 30 percent depth of discharge, maximum acceleration capability gradually degrades. The flywheel system has an estimated life-cycle cost of $0.041/km using lead-acid batteries. The basic system has a life-cycle cost of $0.06/km. The basic system, using batteries meeting ISOA goals, would have a life-cycle cost of $0.043/km.

Raynard, A. E.; Forbes, F. E.

1979-01-01

202

The ac propulsion system for an electric vehicle, phase 1  

Microsoft Academic Search

A functional prototype of an electric vehicle ac propulsion system was built consisting of a 18.65 kW rated ac induction traction motor, pulse width modulated (PWM) transistorized inverter, two speed mechanically shifted automatic transmission, and an overall drive\\/vehicle controller. Design developmental steps, and test results of individual components and the complex system on an instrumented test frame are described. Computer

S. Geppert

1981-01-01

203

The renewable electric plant information system  

SciTech Connect

This report explains the procedures used for creating the Renewable Electric Plant Information System (REPiS) database, describes the database fields, and summarizes the data. The REPiS database contains comprehensive information on grid-connected renewable electric generation plants in the United States. Originally designed in 1987 and updated in 1990, the database includes information through 1994. The report also illustrates ways of using the data for analysis is and describes how researchers validated the data.

Sinclair, K.

1995-12-01

204

Electric airplane environmental control systems energy requirements  

Microsoft Academic Search

The electric airplane environmental control system (ECS) design drivers is discussed for an electric airplane from two aspects. The first aspect considered is the type of aircraft. The three examples selected are the 150-passenger commercial airline transport, the military on-station electronic-surveillance patrol aircraft, and the air-defense interceptor fighter. These vehicle examples illustrate the effect of both mission and mission profile

Linus Buss

1984-01-01

205

Integration of the satellite power system into electric utility systems  

Microsoft Academic Search

The problems of integrating the satellite power system (SPS) into the electric utility system are defined from the perspective of the utility industry. It is assumed that in the post-2000 period when the SPS becomes commercial, regulated private utilities will continue as the major generators and distributors of electrical energy. In these roles, the utilities must interact with federal and

Hub

1978-01-01

206

The mechanical and the electrical properties of conducting polypyrrole fibers  

NASA Astrophysics Data System (ADS)

The mechanical and the electrical properties of polypyrrole (PPy) fibers and electrochemically deposited PPy films were studied. It was found that the PPy fibers showed a significantly higher strength than the PPy films due to better orientation of the molecular structure. The electrochemically prepared PPy films had a higher electrical conductivity than that of the fibers at high temperature. At low temperature, the PPy fibers showed the higher conductivity. The conductivity results were analyzed in the frame of the three-dimensional variable range hopping model. The results showed that at room temperature the average hopping distance for the fibers was about 4 A? while for the films it increases to about 5.7 A?. This corresponds to about 1 and 2 monomer units in length for the fiber and film samples, respectively.

Foroughi, J.; Ghorbani, S. R.; Peleckis, G.; Spinks, G. M.; Wallace, G. G.; Wang, X. L.; Dou, S. X.

2010-05-01

207

Mechanical and electrical properties of ZnO/Ag nanocomposites.  

SciTech Connect

Effects of Ag particle dispersions on microstructural development and some properties were investigated for ZnO/Ag nanocomposites. They were fabricated by Pulse Electric Current Sintering (PECS) Process to achieve finer and densified microstructure. ZnO/Ag nanocomposites with novel microstructure which were prepared by a reduction process using Ag{sub 2}O fine powders were compared with microcomposites prepared by mixing of Ag and ZnO powders. SEM observation indicated that fine Ag particles were homogeneously dispersed within the ZnO matrix grains and at the grain boundaries for ZnO/Ag nanocomposites prepared by the reduction process using Ag{sub 2}O fine powder. Hardness and fracture toughness increased with increasing the Ag volume fraction. Linear resistivity was decreased with increasing Ag volume fraction. However, the mechanical and electrical properties appeared to the significantly different for composites prepared by two different powder processes.

Hayashi, Y.

1998-08-27

208

System Grounding of Electric Submersible Pumps  

Microsoft Academic Search

To ground or not to ground. That is the question. This paper assists in answering that question. Proper system grounding of electrical submersible pumps has long been an issue for debate. Some believe that an ungrounded system is best, whereas others are equally convinced that the opposite is true. Many are not aware of how important the correct answer may

J. H. Solomon

1987-01-01

209

System grounding of electric submersible pumps  

SciTech Connect

To ground or not to ground. That is the question. This paper assists in answering that question. Proper system grounding of electrical submersible pumps has long been an issue for debate. Some believe that an ungrounded system is best, whereas others are equally convinced that the opposite is true. Many are not aware of how important the correct answer may be.

Solomon, J.H.

1987-02-01

210

Direct drive options for electric propulsion systems  

NASA Astrophysics Data System (ADS)

Power processing units (PPU's) in an electric propulsion system provide many challenging integration issues. The PPU must provide power to the electric thruster while maintaining compatibility with all of the spacecraft power and data systems. Inefficiencies in the power processor produce heat, which must be radiated to the environment in order to ensure reliable operation. Although PPU efficiencies are generally greater than 0.9, heat loads are often substantial. This heat must be rejected by thermal control systems which generally have specific masses of 15-30 kg/kW. PPU's also represent a large fraction of the electric propulsion system dry mass. Simplification or elimination of power processing in a propulsion system would reduce the electric propulsion system specific mass and improve the overall reliability and performance. A direct drive system would eliminate all or some of the power supplies required to operate a thruster by directly connecting the various thruster loads to the solar array. The development of concentrator solar arrays has enabled power bus voltages in excess of 300 V which is high enough for direct drive applications for Hall thrusters such as the Stationary Plasma Thruster (SPT). The option of solar array direct drive for SPT's is explored to provide a comparison between conventional and direct drive system mass.

Hamley, John A.

1995-05-01

211

Blackouts in electric power transmission systems  

Microsoft Academic Search

In this paper an analysis of blackouts in electric power transmission systems is implemented and studied in simple networks with a regular structure. The proposed model describes load demand and network improvements evolving on a slow timescale as well as the fast dynamics of cascading overloads and outages. The model dynamics are demonstrated on the simple power system networks.

KARAMITSOS IOANNIS; ORFANIDIS KONSTANTINOS

2006-01-01

212

Electric power system test and verification program  

Microsoft Academic Search

Space Station Freedom's (SSF's) electric power system (EPS) hardware and software verification is performed at all levels of integration, from components to assembly and system level tests. Careful planning is essential to ensure the EPS is tested properly on the ground prior to launch. The results of the test performed on breadboard model hardware and analyses completed to date have

Daniel S. Rylicki; Frank Robinson Jr.

1994-01-01

213

Electrical simulation of the circulatory system  

Microsoft Academic Search

An electrical model of the arterial part of the human vascular system is proposed. This model is used to investigate the impedance, the shape of the pressure and flow waves, and the static characteristics of the vascular system under normal conditions and in the case of artificial circulation. In order to simulate the ACA pump, the problem of the quasi-one-dimensional

A. K. Tsaturyan

1975-01-01

214

FreedomCAR Electrical Energy Storage System Abuse Test Manual for Electric and Hybrid Electric Vehicle Applications.  

National Technical Information Service (NTIS)

This manual defines a complete body of abuse tests intended to simulate actual use and abuse conditions that may be beyond the normal safe operating limits experienced by electrical energy storage systems used in electric and hybrid electric vehicles. The...

C. C. Crafts D. H. Doughty

2006-01-01

215

MEASUREMENT OF SMALL MECHANICAL VIBRATIONS OF BRAIN TISSUE EXPOSED TO EXTREMELY-LOW-FREQUENCY ELECTRIC FIELDS  

EPA Science Inventory

Electromagnetic fields can interact with biological tissue both electrically and mechanically. This study investigated the mechanical interaction between brain tissue and an extremely-low-frequency (ELF) electric field by measuring the resultant vibrational amplitude. The exposur...

216

Mechanical and Electrical Properties of Carbon Nanotube Templated Metal Microstructures  

NASA Astrophysics Data System (ADS)

Our group has used vertically aligned carbon nanotubes as a patterned, three-dimensional microfabrication scaffold to create CNT composite materials through chemical vapor infiltration. This method, termed carbon nanotube templated microfabrication (CNT-M), is a novel approach for creating precise high-aspect-ratio microstructures. In the past, dielectrics (SiO2 and SiNx) and semiconductors (Si and a-C) were the materials deposited on the CNT framework. Production and characterization of metallic microstructures is in its infancy. This study presents electrical, mechanical and structural properties of metallic microstructures made using tungsten and molybdenum carbonyl precursors through the CNT-M process.

Hansen, Richard; McKenna, David; Jensen, Brian; Vanfleet, Richard; Davis, Robert; Allred, David

2011-10-01

217

Analysis and Investigation of Tractor and Trailer Electrical System Capabilities.  

National Technical Information Service (NTIS)

The ability of the tractor-trailer electrical systems to safisfy the electrical powering and signalling demands of present and future electrical/electronic systems appears questionable. The study focused on this issue by: Characterizing the ability of a r...

A. Lesesky T. J. Loughran

1993-01-01

218

Resistive Fault Current Limiter Prototypes: Mechanical and Electrical Analyses  

NASA Astrophysics Data System (ADS)

The problem of excessive short-circuit currents has become an important issue for power systems operators and there are clear indications for a growing interest in superconducting fault current limiter devices for MV and HV grids. In this work, we report on both simulation and electrical testing on single-phase SFCL prototypes developed in the framework of an Italian RTD project to be completed with a 3-phase SFCL unit by the end of 2005.

Martini, L.; Arcos, I.; Bocchi, M.; Brambilla, R.; Dalessandro, R.; Frigerio, A.; Rossi, V.

2006-06-01

219

Electrical and mechanical properties of vapour grown gallium monotelluride crystals  

NASA Astrophysics Data System (ADS)

The physical vapour deposition (PVD) of gallium monotelluride (GaTe) in different crystalline habits was established in the growth ampoule, strongly depending on the temperature gradient. Proper control on the temperatures of source and growth zones in an indigenously fabricated dual zone furnace could yield the crystals in the form of whiskers and spherulites. Optical and electron microscopic images were examined to predict the growth mechanism of morphologies. The structural parameters of the grown spherulites were determined by X-ray powder diffraction (XRD). The stoichiometric composition of these crystals was confirmed using energy dispersive analysis by X-rays (EDAX). The type and nature of electrical conductivity were identified by the conventional hot probe and two probe methods, respectively. The mechanical parameters, such as Vickers microhardness, work hardening index, and yield strength, were deduced from microindentation measurements. The results show that the vapour grown p-GaTe crystals exhibit novel physical properties, which make them suitable for device applications.

Reshmi, P. M.; Kunjomana, A. G.; Chandrasekharan, K. A.

2013-10-01

220

Electric power steering system for vehicles  

SciTech Connect

An electric power steering system for vehicles is described comprising: an input shaft operatively connected to a steering wheel; an output shaft operatively connected to a steered wheel; an electric motor for operatively supplying auxiliary torque to the output shaft; steering torque detection means for detecting steering torque acting on the input shaft; driving control means for feeding the electric motor with a motor drive signal based on an output signal from the steering torque detecting means; steering angle detection means for detecting a steering angle of the steering wheel; and correction means for gradually decreasing the motor drive signal to reduce the auxiliary torque to be developed at the electric motor, when the steering angle of the steering wheel is detected to be exceeding a predetermined angle by the steering angle detection means, the predetermined angle being slightly less than a maximum steering angle of the steering wheel.

Shimizu, Y.; Kawai, T.

1988-03-01

221

MW-Class Electric Propulsion System Designs  

NASA Technical Reports Server (NTRS)

Electric propulsion systems are well developed and have been in commercial use for several years. Ion and Hall thrusters have propelled robotic spacecraft to encounters with asteroids, the Moon, and minor planetary bodies within the solar system, while higher power systems are being considered to support even more demanding future space science and exploration missions. Such missions may include orbit raising and station-keeping for large platforms, robotic and human missions to near earth asteroids, cargo transport for sustained lunar or Mars exploration, and at very high-power, fast piloted missions to Mars and the outer planets. The Advanced In-Space Propulsion Project, High Efficiency Space Power Systems Project, and High Power Electric Propulsion Demonstration Project were established within the NASA Exploration Technology Development and Demonstration Program to develop and advance the fundamental technologies required for these long-range, future exploration missions. Under the auspices of the High Efficiency Space Power Systems Project, and supported by the Advanced In-Space Propulsion and High Power Electric Propulsion Projects, the COMPASS design team at the NASA Glenn Research Center performed multiple parametric design analyses to determine solar and nuclear electric power technology requirements for representative 300-kW class and pulsed and steady-state MW-class electric propulsion systems. This paper describes the results of the MW-class electric power and propulsion design analysis. Starting with the representative MW-class vehicle configurations, and using design reference missions bounded by launch dates, several power system technology improvements were introduced into the parametric COMPASS simulations to determine the potential system level benefits such technologies might provide. Those technologies providing quantitative system level benefits were then assessed for technical feasibility, cost, and time to develop. Key assumptions and primary results of the COMPASS MW-class electric propulsion power system study are reported, and discussion is provided on how the analysis might be used to guide future technology investments as NASA moves to more capable high power in-space propulsion systems.

LaPointe, Michael R.; Oleson, Steven; Pencil, Eric; Mercer, Carolyn; Distefano, Salvador

2011-01-01

222

Electrical appliance energy consumption control methods and electrical energy consumption systems  

DOEpatents

Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

Donnelly, Matthew K. (Kennewick, WA); Chassin, David P. (Pasco, WA); Dagle, Jeffery E. (Richland, WA); Kintner-Meyer, Michael (Richland, WA); Winiarski, David W. (Kennewick, WA); Pratt, Robert G. (Kennewick, WA); Boberly-Bartis, Anne Marie (Alexandria, VA)

2008-09-02

223

Electrical appliance energy consumption control methods and electrical energy consumption systems  

DOEpatents

Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

Donnelly, Matthew K. (Kennewick, WA); Chassin, David P. (Pasco, WA); Dagle, Jeffery E. (Richland, WA); Kintner-Meyer, Michael (Richland, WA); Winiarski, David W. (Kennewick, WA); Pratt, Robert G. (Kennewick, WA); Boberly-Bartis, Anne Marie (Alexandria, VA)

2006-03-07

224

MSFC Skylab electrical power systems mission evaluation  

NASA Technical Reports Server (NTRS)

The design, development, and operation of the Skylab electrical power system are discussed. The electrical systems for the airlock module of the orbital workshop and the Apollo telescope mount are described. Skylab is considered an integral laboratory, however, both cluster and module hardware distinct sections are included. Significant concept and requirement evolution, testing, and modifications resulting from tests are briefly summarized to aid in understanding the launch configuration description and the procedures and performance discussed for in-orbit operation. Specific problems encountered during Skylab orbital missions are analyzed.

Woosley, A. P.

1974-01-01

225

Mechanically refuelable zinc/air electric vehicle cells  

NASA Astrophysics Data System (ADS)

Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells, and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration - factors which define the essential functions of common automobiles. Such an electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J. F.

1992-12-01

226

Mechanically refuelable zinc/air electric vehicle cells  

SciTech Connect

Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration -- factors which define the essential functions of common automobiles. Such a electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described in this report focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J.F.

1992-12-01

227

Classical mechanics of nonconservative systems.  

PubMed

Hamilton's principle of stationary action lies at the foundation of theoretical physics and is applied in many other disciplines from pure mathematics to economics. Despite its utility, Hamilton's principle has a subtle pitfall that often goes unnoticed in physics: it is formulated as a boundary value problem in time but is used to derive equations of motion that are solved with initial data. This subtlety can have undesirable effects. I present a formulation of Hamilton's principle that is compatible with initial value problems. Remarkably, this leads to a natural formulation for the Lagrangian and Hamiltonian dynamics of generic nonconservative systems, thereby filling a long-standing gap in classical mechanics. Thus, dissipative effects, for example, can be studied with new tools that may have applications in a variety of disciplines. The new formalism is demonstrated by two examples of nonconservative systems: an object moving in a fluid with viscous drag forces and a harmonic oscillator coupled to a dissipative environment. PMID:23679733

Galley, Chad R

2013-04-26

228

Visualization of an electric power transmission system  

Microsoft Academic Search

Visualization techniques are applied to an electric power system transmission network to create a graphical picture of network power flows and voltages. A geographic data map is used. Apparent power flow is encoded as the width of an arrow, with direction from real power flow. Flows are superposed on flow limits. Contour plots and color coding failed for representing bus

P. M. Mahadev; R. D. Christie

1994-01-01

229

The Apollo Spacecraft Electrical Power Distribution System  

Microsoft Academic Search

North American Aviation, Inc., is designing and building the Apollo Command and Service Modules at its Space and Information Systems Division, Downey, Calif., under contract to the National Aeronautics and Space Administration's Manned Spacecraft Center, Houston, Texas. The Apollo Spacecraft Command and Service Module obtains primary electrical energy from fuel cells for flight phases until earth re-entry, and from storage

T. C. Quebedeaux

1964-01-01

230

Tidal energy in electric power systems  

Microsoft Academic Search

This paper discusses the uses and advantages of tidal energy in restructured power systems. The paper defines the resources as well as the ways in which tidal energy is converted into electricity. The paper also reviews a few tidal power projects around the world. It also shows the working of hydro tidal power plant. A comparative review of renewable energy

S. Sheth; M. Shahidehpour

2005-01-01

231

Electrically and mechanically tunable electron spins in silicon carbide color centers.  

PubMed

The electron spins of semiconductor defects can have complex interactions with their host, particularly in polar materials like SiC where electrical and mechanical variables are intertwined. By combining pulsed spin resonance with ab initio simulations, we show that spin-spin interactions in 4H-SiC neutral divacancies give rise to spin states with a strong Stark effect, sub-10^{-6} strain sensitivity, and highly spin-dependent photoluminescence with intensity contrasts of 15%-36%. These results establish SiC color centers as compelling systems for sensing nanoscale electric and strain fields. PMID:24856721

Falk, Abram L; Klimov, Paul V; Buckley, Bob B; Ivády, Viktor; Abrikosov, Igor A; Calusine, Greg; Koehl, William F; Gali, Adám; Awschalom, David D

2014-05-01

232

Electrically and Mechanically Tunable Electron Spins in Silicon Carbide Color Centers  

NASA Astrophysics Data System (ADS)

The electron spins of semiconductor defects can have complex interactions with their host, particularly in polar materials like SiC where electrical and mechanical variables are intertwined. By combining pulsed spin resonance with ab initio simulations, we show that spin-spin interactions in 4H-SiC neutral divacancies give rise to spin states with a strong Stark effect, sub-10-6 strain sensitivity, and highly spin-dependent photoluminescence with intensity contrasts of 15%-36%. These results establish SiC color centers as compelling systems for sensing nanoscale electric and strain fields.

Falk, Abram L.; Klimov, Paul V.; Buckley, Bob B.; Ivády, Viktor; Abrikosov, Igor A.; Calusine, Greg; Koehl, William F.; Gali, Ádám; Awschalom, David D.

2014-05-01

233

Cryogenic electrical tests on tokamak insulation system  

Microsoft Academic Search

This paper describes electrical measurements and tests on two possible insulation systems for the Westinghouse Large Coil Program which do not employ vacuum-pressure impregnation. The first of these comprises butt-lapped Kapton tape, covered with B-staged epoxy-loaded glass tape. This system does, however, require post-cure at 150 C. The second employs Tradlon tape covered with bare glass tape. Following this application,

S. K. Singh; A. I. Bennett

1979-01-01

234

Electrical system options for space exploration  

NASA Technical Reports Server (NTRS)

The need for a space power utility concept is discussed and the impact of this concept on the engineering of space power systems is examined. Experiences gained from Space Station Freedom and SEI systems studies are used to discuss the factors that may affect the choice of frequency standards on which to build such a space power utility. Emphasis is given to electrical power control, conditioning, and distribution subsystems.

Bercaw, Robert W.; Cull, Ronald C.

1991-01-01

235

A Xenon Feed System for Electric Propulsion  

Microsoft Academic Search

The Moog XFS offers active pressure and flow control that steps outside of traditional bounds of pressure and flow control feed systems. Traditional pressure and flow control normally relied on a mechanical pressure regulator or \\

Paul T. King; Joseph K. Barbarits

2006-01-01

236

Carbon nanofiller/polymer nanocomposites: Diffusion, mechanical and electrical properties  

NASA Astrophysics Data System (ADS)

Since the discovery two decades ago, fullerene family has drawn remarkable attention because of their unique electrical, thermal, optical, mechanical and flammable properties. They have been widely used to improve polymer properties. These nanofillers produce huge interfacial areas between the polymer and the fillers. Despite the intensive research on fullerene nanocomposites, understanding of the importance of the filler-polymer interface is still limited and further investigation of the structure-property relationships is needed. This dissertation probed influence of nanoparticles on polymer tracer diffusion and molecular weight dependence of composite mechanical properties, and developed a coated particle process to obtain composites with high electrical conductivity. Deuterated polystyrene (dPS) diffusion in nanoparticle/polystyrene (PS) nanocomposites was measured by an elastic recoil detection method. We used single wall carbon nanotubes (SWCNTs), multiwall carbon nanotubes (MWCNTs) and C60 as nanofillers and found that the nanofillers have a significant influence on polymer tracer diffusion. When the tracer molecules ( Rg) are larger than the fillers ( RCNT), the tracer diffusion coefficient exhibits a minimum as a function of filler concentration. In contrast, the tracer diffusion in nanocomposites is constant when the tracer chains are smaller than the fillers. A trap model simulation was developed to understand the minimum diffusion coefficient. The load transfer mechanism from polymer matrix to fillers were studied by tensile testing and Raman spectroscopy in SWCNT/poly(methyl methacrylate) (PMMA) nanocomposite fibers. Without strong filler-polymer interactions, effective load transfer is limited to small strains, and Raman peak shift and stress-strain curve of composite fibers are reversible, suggesting an elastic deformation. Beyond this strain region, the load transfer is nonlinear because of a slippage at the polymer-filler interface. The stress on nanotubes reaches a maximum and then decreases with further increase in the strain. A coated particle process (CPP) method was developed to prepare nanocomposites with a cellular filler structure. The fillers are SWCNTs and PMMA is used as polymer matrix. Compared with the coagulated nanocomposites with well dispersed SWCNTs, the CPP-made nanocomposites have a higher electrical conductivity (2 orders higher), a smaller percolation threshold (50%).

Mu, Minfang

237

Multimegawatt electric propulsion system design considerations  

NASA Technical Reports Server (NTRS)

Piloted Mars Mission Requirements of relatively short trip times and low initial mass in Earth orbit as identified by the NASA Space Exploration Initiative, indicate the need for multimegawatt electric propulsion systems. The design considerations and results for two thruster types, the argon ion, and hydrogen magnetoplasmadynamic thrusters, are addressed in terms of configuration, performance, and mass projections. Preliminary estimates of power management and distribution for these systems are given. Some assessment of these systems' performance in a reference Space Exploration Initiative piloted mission are discussed. Research and development requirements of these systems are also described.

Gilland, J. H.; Myers, Roger M.; Patterson, Michael J.

1991-01-01

238

Hubble Space Telescope electrical power system model  

NASA Technical Reports Server (NTRS)

This paper describes one of the most comprehensive models ever developed for a spacecraft electrical power system (EPS). The model was developed for the Hubble Space Telescope (HST) to evaluate vehicle power system performance and to assist in scheduling maintenance and refurbishment missions by providing data needed to forecast EPS power and energy margins for the mission phases being planned. The EPS model requires a specific mission phase description as the input driver and uses a high granularity database to produce a multi-orbit power system performance report. The EPS model accurately predicts the power system response to various mission timelines over the entire operational life of the spacecraft.

Baggett, Randy; Miller, Jim; Leisgang, Tom

1988-01-01

239

HFA-PFC Systems for Tactical Mobile Electric Power Systems.  

National Technical Information Service (NTIS)

Tactical Mobile Electric Power Systems have the potential for significant weight savings. An average decrease of 87.2% may be achieved through the use of a high frequency alternator - power frequency converter combination, when compared to the standard 18...

M. Hladky

1995-01-01

240

Mechanical responses of the organ of corti to acoustic and electrical stimulation in vitro.  

PubMed

The detection of sound by the cochlea involves a complex mechanical interplay among components of the cochlear partition. An in vitro preparation of the second turn of the jird's cochlea provides an opportunity to measure cochlear responses with subcellular resolution under controlled mechanical, ionic, and electrical conditions that simulate those encountered in vivo. Using photodiode micrometry, laser interferometry, and stroboscopic video microscopy, we have assessed the mechanical responses of the cochlear partition to acoustic and electrical stimuli near the preparation's characteristic frequency. Upon acoustic stimulation, the partition responds principally as a rigid plate pivoting around its insertion along the spiral lamina. The radial motion at the reticular lamina greatly surpasses that of the tectorial membrane, giving rise to shear that deflects the mechanosensitive hair bundles. Electrically evoked mechanical responses are qualitatively dissimilar from their acoustically evoked counterparts and suggest the recruitment of both hair-bundle- and soma-based electromechanical transduction processes. Finally, we observe significant changes in the stiffness of the cochlear partition upon tip-link destruction and tectorial-membrane removal, suggesting that these structures contribute considerably to the system's mechanical impedance and that hair-bundle-based forces can drive active motion of the cochlear partition. PMID:16169985

Chan, Dylan K; Hudspeth, A J

2005-12-01

241

Impulse breakdown mechanism based on discharge propagation process under non-uniform electric field in air  

Microsoft Academic Search

In this paper, we aim to clarify the discharge mechanism leading to breakdown under non-uniform electric field in air, especially on the propagation process of discharge current channel. The discharge measurement was performed in a needle (?1 mm)-plane electrode system with gap length g=15–100 mm in 0.1 MPa dry air under applying a positive impulse voltage. We observed discharge current

Katsuki Hotta; Takeshi Iwata; Hiroki Kojima; Naoki Hayakawa; Norihito Yanagita; Tatsuro Kato; Toshiaki Rokunohe; Hitoshi Okubo

2011-01-01

242

Electrical and mechanical properties of graphene oxide on flexible substrate  

NASA Astrophysics Data System (ADS)

Graphene oxide (GO) was deposited via the electrophoretic deposition (EPD) method to lower the oxygen concentration of graphene sheets for large-scale production. In addition, the direct synthesis of large-scale GO films using transfer processes on a polydimethylsiloxane (PDMS) substrate was conducted. The thickness of the GO films was controlled to adjust the optical, electrical, and mechanical properties. The Young's modulus values of films with thicknesses of 100-200 nm were 324-529 GPa. Moreover, the GO films exhibited excellent conductivity, with a sheet resistance of 276-2024 ?/sq at 23-77% transparency. Experiments show that transfer processes for flexible substrates can produce high-quality cost-effective transparent conductive films.

Kang, Shao-Hui; Fang, Te-Hua; Hong, Zheng-Han

2013-12-01

243

Detection of Alkylating Agents using Electrical and Mechanical Means  

NASA Astrophysics Data System (ADS)

Alkylating agents are reactive molecules having at least one polar bond between a carbon atom and a good leaving group. These often simple molecules are frequently used in organic synthesis, as sterilizing agents in agriculture and even as anticancer agents in medicine. Unfortunately, for over a century, some of the highly reactive alkylating agents are also being used as blister chemical warfare agents. Being relatively simple to make, the risk is that these will be applied by terrorists as poor people warfare agents. The detection and identification of such alkylating agents is not a simple task because of their high reactivity and simple structure of the reactive site. Here we report on new approaches to the detection and identification of such alkylating agents using electrical (organic field effect transistors) and mechanical (microcantilevers) means.

Gerchikov, Yulia; Borzin, Elena; Gannot, Yair; Shemesh, Ariel; Meltzman, Shai; Hertzog-Ronen, Carmit; Tal, Shay; Stolyarova, Sara; Nemirovsky, Yael; Tessler, Nir; Eichen, Yoav

2011-08-01

244

46 CFR 28.845 - General requirements for electrical systems.  

Code of Federal Regulations, 2013 CFR

... § 28.845 General requirements for electrical systems. (a) Electrical equipment exposed to the weather or... (b) Aluminum must not be used for current carrying parts of electrical equipment or wiring. (c) As far...

2013-10-01

245

30 CFR 75.508 - Map of electrical system.  

Code of Federal Regulations, 2013 CFR

...STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.508 Map of electrical system. [Statutory... The location and the electrical rating of all stationary...settings of all direct-current circuit breakers...

2013-07-01

246

Discrete wave mechanics: Multidimensional systems  

PubMed Central

Discrete wave mechanics is pursued further by extending the one-dimensional treatment to two (or more) dimensions in the light of explicit momentum considerations. Cognizance is taken of the effect of particle motion on mass and hence on the interactions between components of motion in different directions. The overall energy parameter turns out to be a product instead of a sum of parameters identified with each of several orthogonal axes. Accordingly, the separation of variables is most directly accomplished by factoring the principal energy parameter in conjunction with factoring the wave vector expression itself. Wave vector energies, on the other hand, remain additive. Finally, group velocity components are discussed for higher-dimensional systems.

Wall, Frederick T.

1987-01-01

247

Circuits and devices in aircraft electrical equipment systems  

NASA Astrophysics Data System (ADS)

Basic properties of electrical circuits and their application in aircraft electrical equipment are studied. Topics of investigation include linear ac circuits, three-phase circuits, transient processes in linear first- and second-order circuits, nonlinear ac and dc circuits, thermoelectric and photoelectric sources of electric energy and electrical transformers, synchronous generators, generators for automated systems, and electric motors and servomechanisms.

Istratov, V. N.

248

Primary electric power generation systems for advanced-technology engines  

NASA Technical Reports Server (NTRS)

The advantages of the all electric airplane are discussed. In the all electric airplane the generator is the sole source of electric power; it powers the primary and secondary flight controls, the environmentals, and the landing gear. Five candidates for all electric power systems are discussed and compared. Cost benefits of the all electric airplane are discussed.

Cronin, M. J.

1983-01-01

249

Evidence for a link between mechanical and electrical alternans in acutely ischaemic myocardium of anaesthetized dogs.  

PubMed

In order to examine the relation between mechanical alternans and associated electrical alternans during acute myocardial ischaemia, we determined the effect of a ventricular premature beat and calcium antagonists on mechanical and electrical alternans during acute coronary occlusion in anaesthetized dogs. Isometric contractions and unipolar electrocardiograms were recorded from ischaemic myocardium. During coronary occlusion, mechanical alternans was accompanied by electrical alternans, which was an alternate change in the ST segment elevation, i.e. the higher ST and the lower ST. Electrical alternans was frequently discordant and in some cases accompanied by discordant mechanical alternans. Both discordant electrical and mechanical alternans became concordant and were potentiated after the ventricular premature beat. In all cases, concordant mechanical alternans was accompanied by concordant electrical alternans and vice versa. In this situation, the higher and the lower ST corresponded to the larger and the smaller contractions respectively. Thus, a fixed correspondence was observed between mechanical and electrical alternans. A fixed correspondence was also observed between mechanical alternans and the variation in the time taken for repolarization of the monophasic action potential. Verapamil and diltiazem inhibited both electrical and mechanical alternans. The present results support the idea that a common mechanism, such as a beat-to-beat cycle of the transmembrane and intracellular movement of calcium ions, may play a role in the mechanisms of electrical and mechanical alternans. PMID:1711268

Hashimoto, H; Nakashima, M

1991-01-01

250

A transition in mechanisms of size dependent electrical transport at nanoscale metal-oxide interfaces  

NASA Astrophysics Data System (ADS)

As device miniaturization approaches nanoscale dimensions, interfaces begin to dominate electrical properties. Here the system archetype Au/SrTiO3 is used to examine the origin of size dependent transport properties along metal-oxide interfaces. We demonstrate that a transition between two classes of size dependent electronic transport mechanisms exists, defined by a critical size ?. At sizes larger than ? an edge-related tunneling effect proportional to 1/D (the height of the supported Au nanoparticle) is observed; interfaces with sizes smaller than ? exhibit random fluctuations in current. The ability to distinguish between these mechanisms is important to future developments in nanoscale device design.

Hou, Jiechang; Nonnenmann, Stephen S.; Qin, Wei; Bonnell, Dawn A.

2013-12-01

251

Solar electric propulsion systems - A survey  

SciTech Connect

The Solar Electric Propulsion System (SEPS) currently under development in the United States offers several advantages as a third-stage power system for interplanetary and inter-earth-orbit flights. Its electric propulsion motors (EPM), with the relatively large specific impulse of 30,000 m/sec each, consume less propellant than do chemical rocket motors or compressed-gas engines, and constitute, with the solar batteries, 50% of the SEPS dry mass. Outfitted with 8-10 energy converters with attainable efficiency of 92%, SEPS is being considered for missions that range from the transport of payloads to geosynchronous orbit to an interplanetary rendezvous with Halley's Comet. The paper also presents configuration options and subsystem parameters.

Grilikhes, V.A.; Zavialova, G.M.; Popov, L.B.

1980-01-01

252

Direct fault location in electrical power systems  

SciTech Connect

This thesis presents an alternative to existing fault locating procedures in electrical power systems. The theoretical approach is based on the adjoint network concept, utilizing Tellegen's theorem. This theorem may be applied in the frequency or time domain. Also the current and voltage measurements taken from different networks, with the same topology and branch numbering, may be taken at different times. The aim is to apply the theorem in locating balanced or unbalanced faults in electric power transmission and distribution systems, using terminal voltage and current measurements combined with a minimum knowledge of the internal voltages and currents of the network. A detailed description of the theoretical basis for the proposed approach is presented along with numerical examples illustrating the potential application of the proposed technique.

Thomas, B.J.

1985-01-01

253

Quantum mechanics of open systems  

NASA Astrophysics Data System (ADS)

In quantum mechanics, there is a set of problems where the system of interest interacts with another system, usually called "environment". This interaction leads to the exchange of energy and information and makes the dynamics of the system of interest essentially non-unitary. Such problems often appeared in condensed matter physics and attracted much attention after recent advances in nanotechnology. As broadly posed as they are, these problems require a variety of different approaches. This thesis is an attempt to examine several of these approaches in applications to different condensed matter problems. The first problem concerns the so-called "Master equation" approach which is very popular in quantum optics. I show that analytic properties of environmental correlators lead to strong restrictions on the applicability of the approach to the strong-coupling regime of interest in condensed matter physics. In the second problem, I use path integrals to treat the localization of particles on attractive short-range potentials when the environment produces an effective viscous friction force. I find that friction changes drastically the localization properties and leads to much stronger localization in comparison to the non-dissipative case. This has implications for the motion of heavy particles in fermionic liquids and, as will be argued below, is also relevant to the problem of high-temperature superconductivity. Finally, the third problem deals with the interplay of geometric phases and energy dissipation which occurs in the motion of vortices in superconductors. It is shown that this interplay leads to interesting predictions for vortex tunneling in high-temperature superconductors which have been partially confirmed by experiments.

Melikidze, Akakii

254

High voltage spacecraft electrical systems design  

NASA Technical Reports Server (NTRS)

Factors which must be considered when designing the best and the most cost-effective high-voltage electrical system for a spacecraft are discussed with particular attention given to the EMC considerations, high-voltage power bus, and harnesses. It is emphasized that the use of serial data buses and lines greatly simplify the harness design and weight. Careful attention to the grounding concept and the EMC requirements is necessary for insuring a 'quiet' spacecraft.

Stone, R. E.

1993-01-01

255

Fault identification for “More Electric” Aircraft distribution systems  

Microsoft Academic Search

The proposals for the “More Electric Aircraft” place a significant, increased demand on the electrical power distribution system. To increase safety and reduce aircraft maintenance times on the ground, there is a greater need to quickly identify and locate electrical faults within the electrical distribution system. The work presented in this paper forms an initial study into the use of

Qian Zhou; Dave Thomas; Mark Sumner

2010-01-01

256

Propulsion system design of electric and hybrid vehicles  

Microsoft Academic Search

There is a growing interest in electric and hybrid-electric vehicles due to environmental concerns. Efforts are directed toward developing an improved propulsion system for electric and hybrid-electric vehicles applications. This paper is aimed at developing the system design philosophies of electric and hybrid vehicle propulsion systems. The vehicles' dynamics are studied in an attempt to find an optimal torque-speed profile

Mehrdad Ehsani; Khwaja M. Rahman; Hamid A. Toliyat

1997-01-01

257

Searching for electrical properties, phenomena and mechanisms in the construction and function of chromosomes.  

PubMed

OUR STUDIES REVEAL PREVIOUSLY UNIDENTIFIED ELECTRICAL PROPERTIES OF CHROMOSOMES: (1) chromosomes are amazingly similar in construction and function to electrical transformers; (2) chromosomes possess in their construction and function, components similar to those of electric generators, conductors, condensers, switches, and other components of electrical circuits; (3) chromosomes demonstrate in nano-scale level electromagnetic interactions, resonance, fusion and other phenomena similar to those described by equations in classical physics. These electrical properties and phenomena provide a possible explanation for unclear and poorly understood mechanisms in clinical genetics including: (a) electrically based mechanisms responsible for breaks, translocations, fusions, and other chromosomal abnormalities associated with cancer, intellectual disability, infertility, pregnancy loss, Down syndrome, and other genetic disorders; (b) electrically based mechanisms involved in crossing over, non-disjunction and other events during meiosis and mitosis; (c) mechanisms demonstrating heterochromatin to be electrically active and genetically important. PMID:24688715

Kanev, Ivan; Mei, Wai-Ning; Mizuno, Akira; Dehaai, Kristi; Sanmann, Jennifer; Hess, Michelle; Starr, Lois; Grove, Jennifer; Dave, Bhavana; Sanger, Warren

2013-01-01

258

Assessment of the Applicability of Mechanical Energy Storage Devices to Electric and Hybrid Vehicles. Volume II.  

National Technical Information Service (NTIS)

The study assesses the ability of mechanical energy storage devices to offer improvements in the performance of electric vehicles. The power and energy required in a storage device to realize specific improvements upon current and near-term electric vehic...

M. W. Schwartz

1979-01-01

259

Searching for Electrical Properties, Phenomena and Mechanisms in the Construction and Function of Chromosomes  

PubMed Central

Our studies reveal previously unidentified electrical properties of chromosomes: (1) chromosomes are amazingly similar in construction and function to electrical transformers; (2) chromosomes possess in their construction and function, components similar to those of electric generators, conductors, condensers, switches, and other components of electrical circuits; (3) chromosomes demonstrate in nano-scale level electromagnetic interactions, resonance, fusion and other phenomena similar to those described by equations in classical physics. These electrical properties and phenomena provide a possible explanation for unclear and poorly understood mechanisms in clinical genetics including: (a) electrically based mechanisms responsible for breaks, translocations, fusions, and other chromosomal abnormalities associated with cancer, intellectual disability, infertility, pregnancy loss, Down syndrome, and other genetic disorders; (b) electrically based mechanisms involved in crossing over, non-disjunction and other events during meiosis and mitosis; (c) mechanisms demonstrating heterochromatin to be electrically active and genetically important.

Kanev, Ivan; Mei, Wai-Ning; Mizuno, Akira; DeHaai, Kristi; Sanmann, Jennifer; Hess, Michelle; Starr, Lois; Grove, Jennifer; Dave, Bhavana; Sanger, Warren

2013-01-01

260

Multiple Mechanisms Switch an Electrically Coupled, Synaptically Inhibited Neuron between Competing Rhythmic Oscillators  

PubMed Central

SUMMARY Rhythmic oscillations are common features of nervous systems. One of the fundamental questions posed by these rhythms is how individual neurons or groups of neurons are recruited into different network oscillations. We modeled competing fast and slow oscillators connected to a hub neuron with electrical and inhibitory synapses. We explore the patterns of coordination shown in the network as a function of the electrical coupling and inhibitory synapse strengths with the help of a novel visualization method that we call the “parameterscape.” The hub neuron can be switched between the fast and slow oscillators by multiple network mechanisms, indicating that a given change in network state can be achieved by degenerate cellular mechanisms. These results have importance for interpreting experiments employing optogenetic, genetic, and pharmacological manipulations to understand circuit dynamics.

Gutierrez, Gabrielle J.; O'Leary, Timothy; Marder, Eve

2013-01-01

261

Analysis of a dynamic speaker in mobile phones by considering mechanical, electrical, and magnetic coupling effects  

NASA Astrophysics Data System (ADS)

With the advent of 3G mobile phones, a combined laptop personal computer and mobile phone can be realized that enables multimedia data communication such as TV streaming, web searching, music play, etc. A dynamic speaker is an essential part to generate high quality sound in the next generation mobile phones. Noting that characteristics of a dynamic speaker are a coupled phenomenon of mechanical, electrical, and magnetic system, a systematic analysis must be implemented to fully consider the coupling effects for an improved design. This paper presents a complete analysis of a dynamic speaker by considering mechanical, electrical and magnetic coupling effects. Results of the analysis are confirmed by the experiments. An improved design of a dynamic speaker is also proposed with enhanced performance.

Hwang, G. Y.; Kim, K. T.; Chung, S. U.; Hwang, S. M.; Kang, B. S.; Hwang, I. C.

2002-05-01

262

Considerations in the design of naval electric power systems  

Microsoft Academic Search

A discussion of the historical approach to the design of U.S. Navy naval electric power systems offers insight into advanced approaches for the design of future naval electric power systems. The unique characteristics of naval electric power systems are discussed, especially with regards to how they contrast with commercial utility power systems. In light of the background and uniqueness, the

John V. Amy Jr

2002-01-01

263

Study on double rotor type driving system of electric vehicle  

NASA Astrophysics Data System (ADS)

Electric vehicle has been developed in many countries as a national project. But its capability is still insufficient for its incompleteness. In energy charging system, the battery is not sufficient to the commercial demand, and in the driving system, initial pick-up and inclined slope capability, maximum high speed, and low efficiency at low speed are its problems. In this study, double-rotor drive system is suggested to overcome the demerit of existing drive system. To improve the efficiency at low speed and to achieve effective control of torque-speed, wound-type induction motor drive system with slip power recovery is adopted and analyzed theoretically. From the results of the analysis, prototype motors are designed and tested to verify this suggestion and analysis. Double-rotor type drive system for electric vehicle suggested in this study shows that acceleration ability is improved 1.8 times that of existing drive system by using the dynamic drive system with pulse driving and the efficiency at low speed is improved by slip power recovery system. Though the mechanical structure is somewhat complex, this system is very robust. A development for commercial application would overcome this difficulty.

Young-Moon, Hwang

264

The ac propulsion system for an electric vehicle, phase 1  

NASA Technical Reports Server (NTRS)

A functional prototype of an electric vehicle ac propulsion system was built consisting of a 18.65 kW rated ac induction traction motor, pulse width modulated (PWM) transistorized inverter, two speed mechanically shifted automatic transmission, and an overall drive/vehicle controller. Design developmental steps, and test results of individual components and the complex system on an instrumented test frame are described. Computer models were developed for the inverter, motor and a representative vehicle. A preliminary reliability model and failure modes effects analysis are given.

Geppert, S.

1981-01-01

265

Interaction of mechanical and electrical oscillations and sensitivity in a model of sensory hair cell  

NASA Astrophysics Data System (ADS)

Sensory hair cells are the first stage in conveying the mechanical stimuli into the electrical signals in auditory and vestibular organs of vertebrates. Experiments showed that hair cells rely on active processes in hair bundles to achieve high selective sensitivity, e.g. due to myosin molecular motors inside stereocilia. In lower vertebrates these active processes result in spontaneous oscillations of hair bundles which can be accompanied by oscillations of the cells' membrane potentials. We use modeling to study how the dynamics of both the membrane potential and the hair bundle interact to produce coherent self-sustained oscillations and how this interaction contributes to the cell's sensitivity to external mechanical perturbations. The model incorporates a mechanical stochastic hair bundle system coupled to a Hodgkin-Huxley type system for the membrane potential. We show that oscillatory regimes result in enhanced sensitivity and selectivity to harmonic stimuli.

Amro, Rami M.; Neiman, Alexander B.

2013-03-01

266

Modeling of an electrical power transmission system using hybrid systems  

Microsoft Academic Search

In this work we proceed to the modeling of an electric power transmission system, using hybrid input\\/output automata (HIOA), based on a framework presented in our previous work. The system is assumed to consist of several distinct components. Some of them such as loads drive the continuous dynamics while others such as protection devices exhibit event-driven discrete dynamics. Such behavior

George K. Fourlas

2005-01-01

267

System reconfiguration on shipboard DC zonal electrical system  

Microsoft Academic Search

In this paper, an automated agent based reconfiguration scheme has been proposed for the DC zonal shipboard electrical system (SES). It is shown that the scheme can reconfigure the system following a disturbance in order to maintain the continuity of supply to loads. The paper identifies the main design issues, which include the number and location of the sectionalizers, primary

Mesut E Baran; Nikhil Mahajan

2005-01-01

268

Optimized design and simulation of electrical capacitance sensor for electrical capacitance tomography system  

Microsoft Academic Search

In this paper a software method for electrical capacitance sensor design of electrical capacitance tomography system is presented by using finite element analysis techniques. Electrical capacitance sensor theory model is established, and capacitance sensitivity field distribution and structure parameters of the sensor to measurement effect are analyzed by the method. The optimized design and simulation of electrical capacitance sensor is

Deyun Chen; Guibin Zheng; Congjing Yang; Xiaoyang Yu

2002-01-01

269

Mechanical, Dynamic Mechanical and Electrical Properties of Conductive Carbon Black\\/Piezoelectric Ceramic\\/Chlorobutyl Rubber Composites  

Microsoft Academic Search

The composites based on conductive carbon black (CCB) and piezoelectric ceramic particles, PMN, and chlorobutyl rubber (CCB\\/PMN\\/IIR) were prepared by compounding and vulcanizing process. Microstructure, mechanical, dynamic mechanical and electrical properties of CCB\\/PMN\\/IIR with various CCB and PMN loading were measured by SEM, mechanical tests, and electrical analysis. The results show tensile properties decrease with increasing PMN loading, while showed

Yanbing Wang; Hao Yan; Zhixiong Huang; Tao Zhang

2012-01-01

270

Electricity Storage Systems and the Grid  

NASA Astrophysics Data System (ADS)

Demand for electricity varies seasonally, daily, and on much shorter time scales. Renewable energy sources such as solar or wind power are naturally intermittent. Nuclear power plants can respond to a narrow range of fluctuating demand quickly and to larger fluctuations in hours. However, they are most efficient when operated at a constant power output. Thus implementing either nuclear power as baseline power or power from renewables requires either a system for storage of electrical energy that can respond quickly to demand or a back-up power source, usually a gas turbine plant that has a quick response time. We have studied six technologies for storing electrical energy from the grid: pumped hydropower, compressed air storage, batteries, flywheels, superconducting magnetic energy storage, and electrochemical capacitors. In addition, the power conversion systems (PCS) that connect storage to the grid are both expensive and critical to the success of a storage technology. Each of these six technologies offers different benefits, is at a different stage of readiness for commercial use, and offers opportunities for research. Advantages and disadvantages for each of the technologies and PCS will be discussed.

Howes, Ruth

2007-04-01

271

Mechanisms and Potential Applications of Intestinal Electrical Stimulation  

Microsoft Academic Search

Purpose  Electrical stimulation of the gut has recently been under intensive investigation and various studies have revealed therapeutic\\u000a potentials of gastrointestinal electrical stimulation for gastrointestinal motility disorders and obesity. While there have\\u000a been a number of reviews on gastric electrical stimulation, there is a lack of systematic reviews on intestinal electrical\\u000a stimulation. The aim of this review is to provide an

Jieyun Yin; Jiande D. Z. Chen

2010-01-01

272

Multiplex electric discharge gas laser system  

NASA Technical Reports Server (NTRS)

A multiple pulse electric discharge gas laser system is described in which a plurality of pulsed electric discharge gas lasers are supported in a common housing. Each laser is supplied with excitation pulses from a separate power supply. A controller, which may be a microprocessor, is connected to each power supply for controlling the application of excitation pulses to each laser so that the lasers can be fired simultaneously or in any desired sequence. The output light beams from the individual lasers may be combined or utilized independently, depending on the desired application. The individual lasers may include multiple pairs of discharge electrodes with a separate power supply connected across each electrode pair so that multiple light output beams can be generated from a single laser tube and combined or utilized separately.

Laudenslager, James B. (inventor); Pacala, Thomas J. (inventor)

1987-01-01

273

Hubble Space Telescope electrical power system  

NASA Technical Reports Server (NTRS)

The Hubble Space Telescope (HST) electrical power system (EPS) is supplying between 2000 and 2400 W of continuous power to the electrical loads. The major components of the EPS are the 5000-W back surface field reflector solar array, the six nickel-hydrogen (NiH2) 22-cell 88-Ah batteries, and the charge current controllers, which, in conjunction with the flight computer, control battery charging. The operation of the HST EPS and the results of the HST NiH2 six-battery test are discussed, and preliminary flight data are reviewed. The HST NiH2 six-battery test is a breadboard of the HST EPS on test at Marshall Space Flight Center.

Whitt, Thomas H.; Bush, John R., Jr.

1990-01-01

274

SNAP-8 electrical generating system development program  

NASA Technical Reports Server (NTRS)

The SNAP-8 program has developed the technology base for one class of multikilowatt dynamic space power systems. Electrical power is generated by a turbine-alternator in a mercury Rankine-cycle loop to which heat is transferred and removed by means of sodium-potassium eutectic alloy subsystems. Final system overall criteria include a five-year operating life, restartability, man rating, and deliverable power in the 90 kWe range. The basic technology was demonstrated by more than 400,000 hours of major component endurance testing and numerous startup and shutdown cycles. A test system, comprised of developed components, delivered up to 35 kWe for a period exceeding 12,000 hours. The SNAP-8 system baseline is considered to have achieved a level of technology suitable for final application development for long-term multikilowatt space missions.

1971-01-01

275

Integrity Mechanisms In Database Management Systems  

Microsoft Academic Search

. Our goal in this paper is to answer the following question: what mechanisms are requiredin a general-purpose multiuser database management system (DBMS) to facilitate the integrityobjectives of information systems? We are particularly interested in relational DBMS's. Althoughexisting commercial products fall far short of providing the requisite mechanisms, in principle theycan be easily extended to incorporate these mechanisms. In a

Ravi Sandhu; Sushil Jajodia

1990-01-01

276

33 CFR 127.107 - Electrical power systems.  

Code of Federal Regulations, 2010 CFR

...WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.107 Electrical power systems. (a) The electrical power system must have a...

2010-07-01

277

46 CFR 28.855 - Electrical distribution systems.  

Code of Federal Regulations, 2013 CFR

...COAST GUARD, DEPARTMENT OF HOMELAND SECURITY UNINSPECTED VESSELS REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.855 Electrical distribution systems. (a) Each electrical distribution system which...

2013-10-01

278

Mine electrical systems evaluation: model coal mine electrical system specifications. Final report  

Microsoft Academic Search

Research indicated a need to physically model a typical a-c\\/d-c coal mine section electrical system. Its purpose would be to permit preliminary evaluations of electrical problem solutions prior to launching full-scale investigations. Such use can result in greater flexibility than that afforded by present computer models. Furthermore, numerous problems, which would be virtually impossible to incorporate in a computer model

L. A. Morley; J. L. Kohler

1974-01-01

279

Electric orbit transfer vehicle cryogenic propellant system  

NASA Astrophysics Data System (ADS)

An electric orbit transfer vehicle (EOTV) is intended to transfer payloads from low Earth orbit (LEO) to higher orbits using low-thrust solar-electric propulsion and hydrogen propellant. Because of its high specific impulse and synergistic sharing of power supply, attitude control and communication systems with the payload, the highly efficient EOTV transfer stage permits use of a smaller, less costly launch vehicle than if orbit transfer were accomplished using chemical propulsion. Study of the propellant storage and supply system for an EOTV intended to fly a 168 day spiral trajectory from LEO to geosynchronous orbit (GEO) reveals that the low propellant flow rate needed by the thrusters can be supplied by the boil-off from the storage tank, eliminating the need for any overboard venting. The tank can be fabricated under the same pressure-stabilized, thin, stainless steel monocoque construction as the current Centaur upper stage, and insulated with Centaur fixed foam and MLI. The tank contains a thermodynamic vent system (TVS) for control of tank pressure in zero and low gravity and for supply of propellant to the thrusters. An external compressor, accumulator and regulator condition the hydrogen boil-off provided by the TVS and provide for start-up and shut-down transients. The resulting system is simple, has a very low structural mass fraction and builds on the Centaur cryogenic upper stage technology, which has been operational for over 25 years.

Schuster, J. R.; Huynh, C. T.; Williams, G. E.

280

Interrogator system for identifying electrical circuits  

DOEpatents

A system for interrogating electrical leads to correctly ascertain the identity of equipment attached to remote ends of the leads is disclosed. The system includes a source of a carrier signal generated in a controller/receiver to be sent over the leads and an identifier unit at the equipment. The identifier is activated by command of the carrier and uses a portion of the carrier to produce a supply voltage. Each identifier is uniquely programmed for a specific piece of equipment, and causes the impedance of the circuit to be modified whereby the carrier signal is modulated according to that program. The modulation can be amplitude, frequency or phase modulation. A demodulator in the controller/receiver analyzes the modulated carrier signal, and if a verified signal is recognized displays and/or records the information. This information can be utilized in a computer system to prepare a wiring diagram of the electrical equipment attached to specific leads. Specific circuit values are given for amplitude modulation, and the system is particularly described for use with thermocouples. 6 figs.

Jatko, W.B.; McNeilly, D.R.

1988-04-12

281

The physics of electric power systems  

NASA Astrophysics Data System (ADS)

The article describes electric power systems from a physicist's point of view. In contrast to common introductory textbooks on power systems, the emphasis is on the physical design, that is the material selection and the choice of the geometrical shape, of the fundamental components as it follows from the function and serves the main purpose. Why do power system components look the way they look? This is the question addressed in an accessible way. Four fundamental components are needed to make the most elementary power system: overhead transmission lines, transformers, synchronous generators, and circuit breakers. High-voltage overhead lines make efficient long-distance transmission of electric power possible. Transformers step up the power from the generating plant and cascade it down to the final consumption. For their ability to control, independently, real and reactive power, synchronous generators are the most common type of generators. And it is only through the immediate extinction of plasma arcs in circuit breakers that shortcircuit currents can be interrupted and faulty segments of the grid disconnected.

Ohler, C.

2013-06-01

282

Interrogator system for identifying electrical circuits  

DOEpatents

A system for interrogating electrical leads to correctly ascertain the identity of equipment attached to remote ends of the leads. The system includes a source of a carrier signal generated in a controller/receiver to be sent over the leads and an identifier unit at the equipment. The identifier is activated by command of the carrier and uses a portion of the carrier to produce a supply voltage. Each identifier is uniquely programmed for a specific piece of equipment, and causes the impedance of the circuit to be modified whereby the carrier signal is modulated according to that program. The modulation can be amplitude, frequency or phase modulation. A demodulator in the controller/receiver analyzes the modulated carrier signal, and if a verified signal is recognized displays and/or records the information. This information can be utilized in a computer system to prepare a wiring diagram of the electrical equipment attached to specific leads. Specific circuit values are given for amplitude modulation, and the system is particularly described for use with thermocouples.

Jatko, William B. (10601 Rivermist La., Knoxville, TN 37922); McNeilly, David R. (Rte. 12, Box 538, Maryville, TN 37801)

1988-01-01

283

Decision support system for regional electricity planning  

Microsoft Academic Search

Electricity appears to be the energy carrier of choice for modern economics since growth in electricity has outpaced growth in the demand for fuels. A decision maker (DM) for accurate and efficient decisions in electricity distribution requires the sector wise and location wise electricity consumption information to predict the requirement of electricity. In this regard, an interactive computer-based Decision Support

T. V. Ramachandra; Vince George; Krishna S. Vamsee; G. B. Purnima

2006-01-01

284

An Investigation on the Coupled Thermal-Mechanical-Electrical Response of Automobile Thermoelectric Materials and Devices  

NASA Astrophysics Data System (ADS)

Thermoelectric (TE) materials, which can directly convert heat to electrical energy, possess wide application potential for power generation from waste heat. As TE devices in vehicle exhaust power generation systems work in the long term in a service environment with coupled thermal-mechanical-electrical conditions, the reliability of their mechanical strength and conversion efficiency is an important issue for their commercial application. Based on semiconductor TE devices wih multiple p- n couples and the working environment of a vehicle exhaust power generation system, the service conditions of the TE devices are simulated by using the finite-element method. The working temperature on the hot side is set according to experimental measurements, and two cooling methods, i.e., an independent and shared water tank, are adopted on the cold side. The conversion efficiency and thermal stresses of the TE devices are calculated and discussed. Numerical results are obtained, and the mechanism of the influence on the conversion efficiency and mechanical properties of the TE materials is revealed, aiming to provide theoretical guidance for optimization of the design and commercial application of vehicle TE devices.

Chen, Gang; Mu, Yu; Zhai, Pengcheng; Li, Guodong; Zhang, Qingjie

2013-07-01

285

Electric System-wide Measurements: North American Directions  

Microsoft Academic Search

The western interconnected electric system of North America pioneered the concept of system-wide measurements, particularly applied to system dynamic issues. This involved the development and deployment of synchronized, sub-second measurement units and their associated data collection networks. More recently, the United States Department of Energy has collaborated with the North American electric reliability council, electric utilities, reliability coordinators, equipment and

Steven E. Widergren; Zhenyu Huang; Jeffery E. Dagle

2007-01-01

286

ac propulsion system for an electric vehicle  

NASA Technical Reports Server (NTRS)

It is pointed out that dc drives will be the logical choice for current production electric vehicles (EV). However, by the mid-80's, there is a good chance that the price and reliability of suitable high-power semiconductors will allow for a competitive ac system. The driving force behind the ac approach is the induction motor, which has specific advantages relative to a dc shunt or series traction motor. These advantages would be an important factor in the case of a vehicle for which low maintenance characteristics are of primary importance. A description of an EV ac propulsion system is provided, taking into account the logic controller, the inverter, the motor, and a two-speed transmission-differential-axle assembly. The main barrier to the employment of the considered propulsion system in EV is not any technical problem, but inverter transistor cost.

Geppert, S.

1980-01-01

287

Wireless distributed functional electrical stimulation system  

PubMed Central

Background The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. Methods The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype’s software. Results The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. Conclusions The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

2012-01-01

288

Analysis of tools for simulation of Shipboard Electric Power Systems  

Microsoft Academic Search

Navy Shipboard Power Systems have different characteristics when compared with utility power systems. To conduct system studies on shipboard power systems, an effective simulation tool is required to model the Shipboard Electric Power Systems. This paper presents the results of the analysis of three popular simulation tools, ATP, PSpice and Saber for transient simulation of Shipboard Electric Power Systems (SPSs).

H. Zhang; K. l. Butler; N. d. r. Sarma; H. Docarmo; S. Gopalakrishnan; A. Adediran

2001-01-01

289

Power-maximizing electrical energy generation system  

US Patent & Trademark Office Database

An electrical energy generation system comprising: a plurality of photovoltaic generators connected in parallel and connected to a common load via respective DC voltage converters; and a regulator configured to vary the transconductances of said respective voltage converters to maximize the power generated by said current generators; wherein: said generators are also connected to a common input of an additional voltage converter the output of which is connected to said common load; and said regulator is also configured to vary the transconductance of said additional voltage converter to maximize the power generated by said current generators.

2010-08-03

290

Optimal management of batteries in electric systems  

DOEpatents

An electric system including at least a pair of battery strings and an AC source minimizes the use and maximizes the efficiency of the AC source by using the AC source only to charge all battery strings at the same time. Then one or more battery strings is used to power the load while management, such as application of a finish charge, is provided to one battery string. After another charge cycle, the roles of the battery strings are reversed so that each battery string receives regular management.

Atcitty, Stanley (Albuquerque, NM); Butler, Paul C. (Albuquerque, NM); Corey, Garth P. (Albuquerque, NM); Symons, Philip C. (Morgan Hill, CA)

2002-01-01

291

Catalog of components for electric and hybrid vehicle propulsion systems  

Microsoft Academic Search

Design and performance specifications are presented for electrical, hydraulic, mechanical, instrumentation, heat exchanger, space conditioning and control equipment which can be used in electric or hybrid-electric vehicles. The components listed in this catalog are presented by individual product category. There are fifty product categories and each has it's individual code as part of the page number. These category codes are

Eissler

1981-01-01

292

77 FR 39857 - Revisions to Electric Reliability Organization Definition of Bulk Electric System and Rules of...  

Federal Register 2010, 2011, 2012, 2013

...electric system'' contained in NERC's Glossary of Terms Used in Reliability Standards (NERC Glossary) developed by the North American Electric...proposed regional differences, and the NERC Glossary, which includes NERC's definition...

2012-07-05

293

International Space Station Electric Power System Performance Code-SPACE  

NASA Technical Reports Server (NTRS)

The System Power Analysis for Capability Evaluation (SPACE) software analyzes and predicts the minute-by-minute state of the International Space Station (ISS) electrical power system (EPS) for upcoming missions as well as EPS power generation capacity as a function of ISS configuration and orbital conditions. In order to complete the Certification of Flight Readiness (CoFR) process in which the mission is certified for flight each ISS System must thoroughly assess every proposed mission to verify that the system will support the planned mission operations; SPACE is the sole tool used to conduct these assessments for the power system capability. SPACE is an integrated power system model that incorporates a variety of modules tied together with integration routines and graphical output. The modules include orbit mechanics, solar array pointing/shadowing/thermal and electrical, battery performance, and power management and distribution performance. These modules are tightly integrated within a flexible architecture featuring data-file-driven configurations, source- or load-driven operation, and event scripting. SPACE also predicts the amount of power available for a given system configuration, spacecraft orientation, solar-array-pointing conditions, orbit, and the like. In the source-driven mode, the model must assure that energy balance is achieved, meaning that energy removed from the batteries must be restored (or balanced) each and every orbit. This entails an optimization scheme to ensure that energy balance is maintained without violating any other constraints.

Hojnicki, Jeffrey; McKissock, David; Fincannon, James; Green, Robert; Kerslake, Thomas; Delleur, Ann; Follo, Jeffrey; Trudell, Jeffrey; Hoffman, David J.; Jannette, Anthony; Rodriguez, Carlos

2005-01-01

294

Method and system for managing an electrical output of a turbogenerator  

DOEpatents

The system and method manages an electrical output of a turbogenerator in accordance with multiple modes. In a first mode, a direct current (DC) bus receives power from a turbogenerator output via a rectifier where turbogenerator revolutions per unit time (e.g., revolutions per minute (RPM)) or an electrical output level of a turbogenerator output meet or exceed a minimum threshold. In a second mode, if the turbogenerator revolutions per unit time or electrical output level of a turbogenerator output are less than the minimum threshold, the electric drive motor or a generator mechanically powered by the engine provides electrical energy to the direct current bus.

Stahlhut, Ronnie Dean (Bettendorf, IA) [Bettendorf, IA; Vuk, Carl Thomas (Denver, IA) [Denver, IA

2010-08-24

295

Garrett Electric Boosting Systems (EBS) Program  

SciTech Connect

Turbo diesel engine use in passenger cars in Europe has resulted in 30-50% improvement in fuel economy. Diesel engine application is particularly suitable for US because of vehicle size and duty cycle patterns. Adopting this technology for use in the US presents two issues--emissions and driveability. Emissions reduction technology is being well addressed with advanced turbocharging, fuel injection and catalytic aftertreatment systems One way to address driveability is to eliminate turbo lag and increase low speed torque. Electrically assisted turbocharging concepts incorporated in e-Turbo{trademark} designs do both The purpose of this project is to design and develop an electrically assisted turbocharger, e-Turbo{trademark}, for diesel engine use in the US. In this report, early design and development of electrical assist technology is described together with issues and potential benefits. In this early phase a mathematical model was developed and verified. The model was used in a sensitivity study. The results of the sensitivity study together with the design and test of first generation hardware was fed into second generation designs. In order to fully realize the benefits of electrical assist technology it was necessary to expand the scope of work to include technology on the compressor side as well as electronic controls concepts. The results of the expanded scope of work are also reported here. In the first instance, designs and hardware were developed for a small engine to quantify and demonstrate benefits. The turbo size was such that it could be applied in a bi-turbo configuration to an SUV sized V engine. Mathematical simulation was used to quantify the possible benefits in an SUV application. It is shown that low speed torque can be increased to get the high performance expected in US, automatic transmission vehicles. It is also shown that e-Turbo{trademark} can be used to generate modest amounts of electrical power and supplement the alternator under most load-speed conditions. It is shown that a single (large) e-Turbo{trademark} consumes slightly less electrical power for the same steady state torque shaping than a bi-Turbo configuration. However, the transient response of a bi-Turbo configuration is slightly better. It was shown that in order to make full use of additional capabilities of e-Turbo{trademark} wide compressor flow range is required. Variable geometry compressor (VGC) technology developed under a separate project was evaluated for incorporation into e-Turbo{trademark} designs. It was shown that the combination of these two technologies enables very high torque at low engine speeds. Designs and hardware combining VGC and e-Turbo{trademark} are to be developed in a future project. There is concern about high power demands (even though momentary) of e-Turbo{trademark}. Reducing the inertia of the turbocharger can reduce power demand and increase battery life. Low inertia turbocharger technology called IBT developed under a separate project was evaluated for synergy with e-Turbo{trademark} designs. It was concluded that inertial reduction provided by IBT is very beneficial for e-Turbo{trademark}. Designs and hardware combining IBT and e-Turbo{trademark} are to be developed in a future project. e-Turbo{trademark} provides several additional flexibilities including exhaust gas recirculation (EGR) for emissions reduction with minimum fuel economy penalty and exhaust temperature control for aftertreatment. In integrated multi-parameter control system is needed to realize the full potential of e-Turbo{trademark} performance. Honeywell expertise in process control systems involving hundreds of sensors and actuators was applied to demonstrate the potential benefits of multi-parameter, model based control systems.

Steve Arnold; Craig Balis; Pierre Barthelet; Etienne Poix; Tariq Samad; Greg Hampson; S. M. Shahed

2005-03-31

296

POWERHU-a PC-based electric power system analysis software package for electric power system courses  

Microsoft Academic Search

A software package is developed to perform electrical power system analysis on a personal computer. The software is capable of performing impedance calculations, load-flow studies, fault analysis and transient-stability analyses of electric power systems. It is intended for electric power system students, and is realized in such a manner that a problem can be solved by using alternative methods. Each

M. Songur; B. Ercan

1997-01-01

297

Rivaroxaban modulates electrical and mechanical characteristics of left atrium  

PubMed Central

Background Rivaroxaban reduces stroke in patients with atrial fibrillation (AF). Left atrium (LA) plays a critical role in the pathophysiology of AF. However, the electromechanical effects of rivaroxaban on LA are not clear. Results Conventional microelectrodes and a whole-cell patch-clamp were used to record the action potentials (APs) and ionic currents in rabbit LA preparations and isolated single LA cardiomyocytes before and after the administration of rivaroxaban. Rivaroxaban (10, 30, 100, and 300 nM) concentration-dependently reduced LA (n?=?7) AP durations at 90% repolarization (APD90) from 76?±?2 to 79?±?3, 67?±?4 (P?electrical and mechanical characteristics with direct ionic current effects.

2013-01-01

298

System performance predictions for Space Station Freedom's electric power system  

Microsoft Academic Search

Space Station Freedom Electric Power System (EPS) capability to effectively deliver power to housekeeping and user loads continues to strongly influence Freedom's design and planned approaches for assembly and operations. The EPS design consists of silicon photovoltaic (PV) arrays, nickel-hydrogen batteries, and direct current power management and distribution hardware and cabling. To properly characterize the inherent EPS design capability, detailed

Thomas W. Kerslake; Jeffrey S. Hojnicki; Robert D. Green; Jeffrey C. Follo

1993-01-01

299

Stress relaxation in porcine septal cartilage during electromechanical reshaping: mechanical and electrical responses.  

PubMed

Electromechanical reshaping (EMR) of facial cartilage has recently been developed as an alternative to classic surgical techniques to alter cartilage shape. This study focuses on determining the underlying physical mechanisms responsible for shape change (stress relaxation) in mechanically deformed facial cartilage specimens exposed to constant electric fields. Flat porcine nasal septal cartilage specimens were deformed by an aluminum jig into semicylindrical shapes while a constant electric voltage was applied to the concave and convex surfaces of the specimen. Mechanical stress, electric current and resistance were measured during voltage application. Specimen shape retention was measured as retained bend angle. Total electric charge transferred in the electric circuit was calculated from the electric current measurement. Electrical resistance, transferred charge and the bend angle increase with increase in voltage application time until bend angle reaches maximum value determined by the jig geometry. Then, the bend angle decreases and electrical parameters nearly saturate. The time dependent behavior of electric current was analyzed using the Cottrell equation. The observed changes in electric current suggest that during the initial 1-2 min of EMR nonlinear diffusion determines electro-chemical reaction rates, which are then followed by a linear diffusion dominated process. Close correlation between alteration of cartilage mechanical state and change in its electrical properties suggest that an electro-chemical reaction is the dominant mechanism behind EMR. PMID:16450186

Protsenko, Dmitriy E; Ho, Kevin; Wong, Brian J F

2006-03-01

300

The quartz crystal resonator as detector of electrical loading: an analysis of sensing mechanisms  

Microsoft Academic Search

Quartz crystal resonators (QCR) are being investigated for the detection of electrical properties of an adjacent medium. Recent studies have suggested that the sensitivity can be improved by utilizing modified electrode configuration. In this study, an analysis of the electrical loading sensing mechanism and of the mass sensitively profile are performed for examples of modified-electrode QCRs. The total electric field

YOUBOK LEE; D. Everhart; F. Josse

1996-01-01

301

Reconfigurable bioimpedance emulation system for electrical impedance tomography system validation.  

PubMed

This paper presents a novel bioimpedance emulation method designed for electrical impedance tomography system validation. The proposed method can emulate the impedance frequency characteristics of various biological samples from user configurations. The bioimpedance emulation system is realized in a hardware prototype comprising current sensing circuitry, voltage generating circuitry, a USB controller and a field-programmable gate array (FPGA) for reconfigurable digital control of emulated impedance. Experimental validation shows that the emulation system exhibits good accuracy ( > 97% at 1 kOhm magnitude) in the frequency range 1 kHz to 1 MHz. The digitally configurability offers advantages in flexibility, repeatability, and cost-efficient compared to more traditional approaches, simplifying the validation process of electrical impedance tomography systems. PMID:23893205

Li, Nan; Xu, Hui; Zhou, Zhou; Xin, Jinling; Sun, Zhaolin; Xu, Xin

2013-08-01

302

Operating health analysis of electric power systems  

NASA Astrophysics Data System (ADS)

The required level of operating reserve to be maintained by an electric power system can be determined using both deterministic and probabilistic techniques. Despite the obvious disadvantages of deterministic approaches there is still considerable reluctance to apply probabilistic techniques due to the difficulty of interpreting a single numerical risk index and the lack of sufficient information provided by a single index. A practical way to overcome difficulties is to embed deterministic considerations in the probabilistic indices in order to monitor the system well-being. The system well-being can be designated as healthy, marginal and at risk. The concept of system well-being is examined and extended in this thesis to cover the overall area of operating reserve assessment. Operating reserve evaluation involves the two distinctly different aspects of unit commitment and the dispatch of the committed units. Unit commitment health analysis involves the determination of which unit should be committed to satisfy the operating criteria. The concepts developed for unit commitment health, margin and risk are extended in this thesis to evaluate the response well-being of a generating system. A procedure is presented to determine the optimum dispatch of the committed units to satisfy the response criteria. The impact on the response wellbeing being of variations in the margin time, required regulating margin and load forecast uncertainty are illustrated. The effects on the response well-being of rapid start units, interruptible loads and postponable outages are also illustrated. System well-being is, in general, greatly improved by interconnection with other power systems. The well-being concepts are extended to evaluate the spinning reserve requirements in interconnected systems. The interconnected system unit commitment problem is decomposed into two subproblems in which unit scheduling is performed in each isolated system followed by interconnected system evaluation. A procedure is illustrated to determine the well-being indices of the overall interconnected system. Under normal operating conditions, the system may also be able to carry a limited amount of interruptible load on top of its firm load without violating the operating criterion. An energy based approach is presented to determine the optimum interruptible load carrying capability in both the isolated and interconnected systems. Composite system spinning reserve assessment and composite system well-being are also examined in this research work. The impacts on the composite well-being of operating reserve considerations such as stand-by units, interruptible loads and the physical locations of these resources are illustrated. It is expected that the well-being framework and the concepts developed in this research work will prove extremely useful in the new competitive utility environment.

Fotuhi-Firuzabad, Mahmud

303

Statistical mechanics and disordered systems  

Microsoft Academic Search

Since computers are able to simulate the equilibrium properties of model systems, they may also prove useful for solving the hard optimization problems that arise in the engineering of complex systems.

Scott Kirkpatrick; Robert H. Swendsen

1985-01-01

304

Analysis of electric-submersible-pumping systems  

SciTech Connect

This paper presents a field-proven analytical method of evaluating electric-submersible-pumping equipment and well performance jointly. A computerized mathematical model that considers the effects of free gas, pump speed (variable-frequency drives), and pump tapering is described. The method allows accurate calculations of important downhole parameters, including pump intake pressure, pump intake volume (including free gas), pump pressure, and fluid density profile. Lifting cost parameters - such as pump and motor power requirements, monthly power consumption, pump and motor performance, and overall system efficiency - are also determined. Once operating conditions are known, decisions can be made on ways to increase production (if additional potential exists) or to reduce operating costs. Thus, the same basic goals that often justify frequent analysis of rod pumping systems can be applied to submersible pumping.

Nolen, K.B.; Gibbs, S.G.

1989-05-01

305

Mechanical recycling of waste electric and electronic equipment: a review  

Microsoft Academic Search

The production of electric and electronic equipment (EEE) is one of the fastest growing areas. This development has resulted in an increase of waste electric and electronic equipment (WEEE). In view of the environmental problems involved in the management of WEEE, many counties and organizations have drafted national legislation to improve the reuse, recycling and other forms of recovery of

Jirang Cui; Eric Forssberg

2003-01-01

306

Mountain Plains Learning Experience Guide: Automotive Repair. Course: Electrical Systems.  

ERIC Educational Resources Information Center

One of twelve individualized courses included in an automotive repair curriculum, this course covers the theory, diagnosis, repair, and adjustment of automotive electrical systems. The course is comprised of six units: (1) Fundamentals of Electrical Systems, (2) Battery Servicing, (3) Starting Systems, (4) Charging Systems, (5) Ignition Systems

Schramm, C.; Osland, Walt

307

Synthesis of nanopowders under high frequency electric discharge assisted mechanical milling  

Microsoft Academic Search

Electric discharge assisted mechanical milling can be applied to the synthesis of a range of fine powder products, including nanocrystalline agglomerates and individual nanoparticles and nanofragments. Processing variables include: starting powder sample size; electric arc parameters such as arc length and arc voltage\\/current; mechanical milling parameters; gas atmosphere and ionized gas species present. We describe results of an initial experimental

A. Calka; D. Wexler; A. Y. Mosbah

2007-01-01

308

Assessment of the applicability of mechanical energy storage devices to electric and hybrid vehicles. Volume II  

Microsoft Academic Search

The study assesses the ability of mechanical energy storage devices to offer improvements in the performance of electric vehicles. The power and energy required in a storage device to realize specific improvements upon current and near-term electric vehicle performance specifications are calculated. Candidate mechanical energy storage devices are reviewed. It is concluded that only flywheels and, for some applications, hydraulic

1979-01-01

309

Water involvement in the mechanisms of retina electrical activity  

SciTech Connect

Retina is an excitable system containing approximately 90% water. As we found that deuteration selectively changes amplitudes and latencies of retina biopotentials, specifically the ON and OFF responses, we used it to probe the role of water in those processes. A study of the retina deuteration kinetics was simultaneously performed. This revealed the existence of at least two retinal water compartments. The data suggested a third compartment also, with a lower motional ''degree of freedom,'' existing where H/sub 2/O-D/sub 2/O exchange becomes important only after saturation by D/sub 2/O of the first two compartments. Correlation of the electrophysiological effects of D/sub 2/O with the kinetic data suggests that the ON response is related to the first water compartment and the OFF response to the third. The results point to independence on the ON and OFF response mechanisms and, very probably, to their different morphological origins.

Chirieri-Kovacs, E.; Vasilescu, V.

1982-01-01

310

Space station electrical power system availability study  

NASA Technical Reports Server (NTRS)

ARINC Research Corporation performed a preliminary reliability, and maintainability (RAM) anlaysis of the NASA space station Electric Power Station (EPS). The analysis was performed using the ARINC Research developed UNIRAM RAM assessment methodology and software program. The analysis was performed in two phases: EPS modeling and EPS RAM assessment. The EPS was modeled in four parts: the insolar power generation system, the eclipse power generation system, the power management and distribution system (both ring and radial power distribution control unit (PDCU) architectures), and the power distribution to the inner keel PDCUs. The EPS RAM assessment was conducted in five steps: the use of UNIRAM to perform baseline EPS model analyses and to determine the orbital replacement unit (ORU) criticalities; the determination of EPS sensitivity to on-orbit spared of ORUs and the provision of an indication of which ORUs may need to be spared on-orbit; the determination of EPS sensitivity to changes in ORU reliability; the determination of the expected annual number of ORU failures; and the integration of the power generator system model results with the distribution system model results to assess the full EPS. Conclusions were drawn and recommendations were made.

Turnquist, Scott R.; Twombly, Mark A.

1988-01-01

311

Stability analysis of motor drive interactions in aircraft electrical systems  

Microsoft Academic Search

More Electric Aircraft are currently being developed so that in the future all non-propulsive power on an aircraft can be provided by the electrical system. In this electrical system, it is expected that several motor loads will run in parallel from a single DC bus. The paper will investigate the interactions between five motor loads connected to a common DC

C. E. Jones; M. Barnes; A. J. Forsyth

2011-01-01

312

Electrical power distribution system operating experience review for fusion applications  

Microsoft Academic Search

This paper describes safety research on electrical distribution systems applicable to fusion facilities. Electrical power has many uses in both magnetic and inertial fusion experiments; it is the most important support system for any fusion experiment. Electricity powers a wide variety of plant equipment, including vacuum pumps, magnets, coolant pumps, air handlers, compressors, and either plasma heating or target implosion

L. C Cadwallader

2002-01-01

313

Supermarket refrigeration assessment for the New England Electric System  

Microsoft Academic Search

The Electric Power Research Institute (EPRI) has undertaken a project to assess the impact of energy efficient supermarket refrigeration on the electric capacity requirements of the New England Electric System (NEES) service territories. The leading supermarket chains in the NEES service territories were contacted and the number of supermarkets and the types of refrigeration systems employed were established. Estimates were

T. L. Tsaros; D. H. Walker

1991-01-01

314

Torsional Vibration Analysis of a Long Propeller Shaft System Driven by an Electric Motor (Electric System).  

National Technical Information Service (NTIS)

The report presents a torsional vibration analysis of a ship's propeller shaft system driven by an electric motor. The propeller shaft is unusually long at 43 meters. The results of the analysis are evaluated on basis of the specifications of Lloyd's Regi...

H. S. Brockhoff P. P. Lemmen

1995-01-01

315

Fracture criterion for conductive cracks in soda-lime glass under combined mechanical and electrical loading  

Microsoft Academic Search

Fracture tests of electrically conductive cracks on pre-notched four-point bending soda-lime glass samples were conducted\\u000a under combined mechanical and electrical loading. The experimental results show that the critical stress intensity factor\\u000a at fracture is reduced if an electric field is applied, thereby indicating that the electric field makes contributions to\\u000a the fracture of conductive cracks. Base on the charge-free zone

Dong-Jun Yan; Hai-You Huang; Chi-Wai Cheung; Tong-Yi Zhang

2010-01-01

316

AC propulsion system for an electric vehicle, phase 2  

NASA Astrophysics Data System (ADS)

A second-generation prototype ac propulsion system for a passenger electric vehicle was designed, fabricated, tested, installed in a modified Mercury Lynx vehicle and track tested at the Contractor's site. The system consisted of a Phase 2, 18.7 kw rated ac induction traction motor, a 192-volt, battery powered, pulse-width-modulated, transistorized inverter packaged for under rear seat installation, a 2-axis, 2-speed, automatically-shifted mechanical transaxle and a microprocessor-based powertrain/vehicle controller. A diagnostics computer to assist tuning and fault finding was fabricated. Dc-to-mechanical-system efficiency varied from 78% to 82% as axle speed/torque ranged from 159 rpm/788 nm to 65 rpm/328 nm. Track test efficiency results suggest that the ac system will be equal or superior to dc systems when driving urban cycles. Additional short-term work is being performed under a third contract phase (AC-3) to raise transaxle efficiency to predicted levels, and to improve starting and shifting characteristics. However, the long-term challenge to the system's viability remains inverter cost. A final report on the Phase 2 system, describing Phase 3 modifications, will be issued at the conclusion of AC-3.

Slicker, J. M.

1983-06-01

317

Efficient Probabilistic Diagnostics for Electrical Power Systems  

NASA Technical Reports Server (NTRS)

We consider in this work the probabilistic approach to model-based diagnosis when applied to electrical power systems (EPSs). Our probabilistic approach is formally well-founded, as it based on Bayesian networks and arithmetic circuits. We investigate the diagnostic task known as fault isolation, and pay special attention to meeting two of the main challenges . model development and real-time reasoning . often associated with real-world application of model-based diagnosis technologies. To address the challenge of model development, we develop a systematic approach to representing electrical power systems as Bayesian networks, supported by an easy-to-use speci.cation language. To address the real-time reasoning challenge, we compile Bayesian networks into arithmetic circuits. Arithmetic circuit evaluation supports real-time diagnosis by being predictable and fast. In essence, we introduce a high-level EPS speci.cation language from which Bayesian networks that can diagnose multiple simultaneous failures are auto-generated, and we illustrate the feasibility of using arithmetic circuits, compiled from Bayesian networks, for real-time diagnosis on real-world EPSs of interest to NASA. The experimental system is a real-world EPS, namely the Advanced Diagnostic and Prognostic Testbed (ADAPT) located at the NASA Ames Research Center. In experiments with the ADAPT Bayesian network, which currently contains 503 discrete nodes and 579 edges, we .nd high diagnostic accuracy in scenarios where one to three faults, both in components and sensors, were inserted. The time taken to compute the most probable explanation using arithmetic circuits has a small mean of 0.2625 milliseconds and standard deviation of 0.2028 milliseconds. In experiments with data from ADAPT we also show that arithmetic circuit evaluation substantially outperforms joint tree propagation and variable elimination, two alternative algorithms for diagnosis using Bayesian network inference.

Mengshoel, Ole J.; Chavira, Mark; Cascio, Keith; Poll, Scott; Darwiche, Adnan; Uckun, Serdar

2008-01-01

318

30 CFR 36.32 - Electrical components and systems.  

Code of Federal Regulations, 2013 CFR

...Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...REQUIREMENTS FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION...a) Electrical components on mobile diesel-powered transportation... (b) Electrical systems on mobile diesel-powered...

2013-07-01

319

System for Measuring the Local Electrical Conductivity of Plasma.  

National Technical Information Service (NTIS)

The system for measuring the local electrical conductivity of the plasma of products of combustion (SILYeP) is intended for investigation of the distribution of electrical conductivity of the ionized gas flows (plasma) and the determination of the electri...

N. A. Balashov I. M. Gaponov G. P. Malyuzhonok Y. S. Mikhailov F. M. Oberman

1975-01-01

320

Electric and Hybrid Vehicle Systems Assessment Seminar: Proceedings.  

National Technical Information Service (NTIS)

The following twenty papers are included in these proceedings: (1) electric and hybrid vehicle assessment overview, (2) electric and hybrid vehicle systems considerations, (3) advanced vehicle assessment, (4) hybrid vehicle assessment, (5) battery optimiz...

1984-01-01

321

Precise Time and Time Interval Applications to Electric Power Systems.  

National Technical Information Service (NTIS)

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on ...

R. E. Wilson

1992-01-01

322

Precise Time and Time Interval Applications to Electric Power Systems.  

National Technical Information Service (NTIS)

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on ...

R. E. Wilson

1991-01-01

323

Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations  

NASA Technical Reports Server (NTRS)

The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

Raynard, A. E.; Forbes, F. E.

1980-01-01

324

Electrical swing adsorption gas storage and delivery system  

DOEpatents

Systems and methods for electrical swing natural gas adsorption are described. An apparatus includes a pressure vessel; an electrically conductive gas adsorptive material located within the pressure vessel; and an electric power supply electrically connected to said adsorptive material. The adsorptive material can be a carbon fiber composite molecular sieve (CFCMS). The systems and methods provide advantages in that both a high energy density and a high ratio of delivered to stored gas are provided.

Judkins, Roddie R. (Knoxville, TN); Burchell, Timothy D. (Oak Ridge, TN)

1999-01-01

325

Electrical swing adsorption gas storage and delivery system  

DOEpatents

Systems and methods for electrical swing natural gas adsorption are described. An apparatus includes a pressure vessel; an electrically conductive gas adsorptive material located within the pressure vessel; and an electric power supply electrically connected to said adsorptive material. The adsorptive material can be a carbon fiber composite molecular sieve (CFCMS). The systems and methods provide advantages in that both a high energy density and a high ratio of delivered to stored gas are provided. 5 figs.

Judkins, R.R.; Burchell, T.D.

1999-06-15

326

Mechanism of electric fatigue crack growth in lead zirconate titanate  

Microsoft Academic Search

A series of experiments was performed with through-thickness cracks in ferroelectric double cantilever beam (DCB) specimens. Cyclic electric fields of different amplitudes were applied which resulted in cyclic crack propagation perpendicular to the electric field direction. Crack propagation was observed optically and three regimes were identified: a pop-in from a notch, steady-state crack growth and a decrease of the crack

Ilona Westram; William S. Oates; Doru C. Lupascu; Jürgen Rödel; Christopher S. Lynch

2007-01-01

327

Dual power, constant speed electric motor system  

DOEpatents

A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level.

Kirschbaum, Herbert S. (Asheville, NC)

1984-01-01

328

Dual power, constant speed electric motor system  

DOEpatents

A dual capacity permanent split capacitor electric motor system is provided with a stator having main and auxiliary windings. The main stator winding includes two winding sections which are connected in parallel with each other and across a pair of line terminals while the auxiliary winding is connected in series with a capacitor to form a circuit branch which is connected between the line terminals for operation at a first output power level. Switching means are provided to reconnect the main stator winding sections in series with each other and in series with a second capacitor to form a circuit branch which is connected between the line terminals while the stator auxiliary winding is connected directly between the line terminals for operation at a second output power level. Automatic rotation reversal occurs when the motor switches from the first to the second output power level. 6 figs.

Kirschbaum, H.S.

1984-07-31

329

Traction Control System for Formula Student Electric  

NASA Astrophysics Data System (ADS)

This paper deals with design of traction control of Formula Student Electric Car. There will introduced new conception of formula traction system and its application to the Formula car. In next season we would like to use 2 motors, each of them will be directly connected to its wheel. This solution needs precise control of them to provide high dynamics and great ability to ride curves in high speeds. Using the same torque on each wheel brings problem when one of wheel loss the traction ability. Some slip could happen and the unexpected lateral movement becomes. There will described the mathematic model of formula car. To reduce slips etc. we will publish the theoretical algorithm that reduces or increases torques on rear wheels to stabilize the car. There will be described what states have to be measured and evaluated. Also places where the sensors will be placed will be shown.

Houf, Z.; ?e?ovský, Z.; Hlinovský, V.

330

DOE/ORNL electric systems program overview  

NASA Astrophysics Data System (ADS)

Major projects in electric systems program include two experiments, one laboratory study, one data survey and an analysis effort. The TECH site work has focused on state-of-the-art (SOA) single speed residential air-to-air heat pumps for the past few years, but is currently changing to a SOA two speed unit. The preprototype dual stroke advanced heat pump was developed and is tested. The laboratory study is aimed at detailed measurement of refrigerant migration with varying on off cycles, frost formation with varying relative humidities, and other such factors to develop an understanding of effect and cause of dynamic losses. The field performance data survey is a project to determine the extent and quality of data that are available on heat pump field performance from manufacturers, utilities, and others.

Fairchild, P. D.

331

Electrical system architecture having high voltage bus  

SciTech Connect

An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

Hoff, Brian Douglas (East Peoria, IL); Akasam, Sivaprasad (Peoria, IL)

2011-03-22

332

The structure of 2-bodies mechanical systems  

Microsoft Academic Search

Under-actuated 2-bodies mechanical systems with 1 actuator are considered. This family of systems includes the double pendulum, the inverted pendulum on a cart, the acrobot, the pendubot... and other systems with two degrees of freedom but only one actuated joint. The maximal linearization problem is investigated and it is shown that these systems may be classified into two subfamilies depending

Jiri Zikmund; Claude H. Moog

2006-01-01

333

Integration of the Premium Power Supply on Electric Power System  

Microsoft Academic Search

This paper describes an inverter-interfaced distributed generation (DG) system that is interconnected with the electric power system (EPS). This system has two main goals such as to serve the customer with reliable electric power and to improve power quality like harmonics and voltage event. This system is interfaced through the series and the shunt inverters because inverters are effective to

Jin-Woo Park; Il-Yop Chung; Kyoung-Nam Kim; Jong-Hun Lee; Seung-Il Moon; Byung-Moon Han

2005-01-01

334

Advanced Electric Traction System Technology Development  

SciTech Connect

As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.

Anderson, Iver

2011-01-14

335

Applications of superconductors in electric utility systems  

Microsoft Academic Search

Superconductors hold a level of attractiveness for electric utility applications because they can carry large electrical current densities with no or with very small electric power dissipation. Achievable current densities are large enough that it is possible, using superconductors, to produce magnetic flux densities higher than those required to saturate iron. This holds out the prospect for improving the energy

1999-01-01

336

The Tractor Electrical System. A Teaching Reference.  

ERIC Educational Resources Information Center

The fundamental principles underlying the application of electricity to tractors and farm equipment are presented. An understanding of the material in the basic manual will enable the service man to understand better the service procedures covered in service manuals on electrical equipment. Topics dealt with are fundamentals of electricity

American Association for Vocational Instructional Materials, Athens, GA.

337

Mechanical and Electrical Clamping of DEP Assembled SWCNT Using Electroless Gold Deposition  

NASA Astrophysics Data System (ADS)

In this paper, we report on a method to assemble and clamp single walled carbon nanotubes (SWCNTs) mechanically and electrically on patterned electrodes for developing a new tensile testing method which achieves SWCNT mechanical characterization with high throughput. Electrical transport measurement on assembled SWCNTs was conducted in order to characterize clamping property. Theoretical analysis based on the obtained result reveals that the proposed mechanical clamp is sufficiently strong to conduct tensile testing of SWCNT.

Kataoka, Tatsuya; Hirai, Yoshikazu; Sugano, Koji; Tsuchiya, Toshiyuki; Tabata, Osamu

338

Statistical mechanics of program systems  

NASA Astrophysics Data System (ADS)

We discuss the collective behaviour of a set of operators and variables that constitute a program and the emergence of meaningful computational properties in the language of statistical mechanics. This is done by appropriately modifying available Monte Carlo methods to deal with hierarchical structures. The study suggests, in analogy with simulated annealing, a method to automatically design programs. Reasonable solutions can be found, at low temperatures, when the method is applied to simple toy problems such as finding an algorithm that determines the roots of a function or one that makes a nonlinear regression. Peaks in the specific heat are interpreted as signalling phase transitions which separate regions where different algorithmic strategies are used to solve the problem.

Neirotti, Juan P.; Caticha, Nestor

2006-08-01

339

Integrated mechanically based CAE system  

Microsoft Academic Search

In the product development cycle interaction between design and analysis is very intensive. However, currently existing Computer Aided Engineering (CAE) systems substantially limit such interaction since design and analysis are realized in them as two isolated modules. These limitations can be distinguished on two levels: the conceptual level and the technical level. On the conceptual level a gap exists according

Pavel Kagan; Anath Fischer; Pinhas Z. Bar-Yoseph

1999-01-01

340

Primary electric propulsion technology study. [for thruster wear-out mechanisms  

NASA Technical Reports Server (NTRS)

An investigation of the 30-cm engineering-model-thruster technology with emphasis placed on the development of models for understanding and predicting the operational characteristics and wear-out mechanisms of the thruster as a function of operating or design parameters is presented. The task studies include: (1) the wear mechanisms and wear rates that determine the useful lifetime of the thruster discharge chamber; (2) cathode lifetime as determined by the depletion of barium from the barium-aluminate-impregnated-porous-tungsten insert that serves as a barium reservoir; (3) accelerator-grid-system technology; (4) a verification of the high-voltage propellant-flow-electrical-isolator design developed under NASA contract NAS3-20395 for operation at 10-kV applied voltage and 10-A equivalent propellant flow with mercury and argon propellants. A model was formulated for predicting performance.

Poeschel, R. L.; Beattie, J. R.

1979-01-01

341

Regulation of Cell Cytoskeleton and Membrane Mechanics by Electric Field: Role of Linker Proteins  

PubMed Central

Abstract Cellular mechanics is known to play an important role in the cell homeostasis including proliferation, motility, and differentiation. Significant variation in the mechanical properties between different cell types suggests that control of the cell metabolism is feasible through manipulation of the cell mechanical parameters using external physical stimuli. We investigated the electrocoupling mechanisms of cellular biomechanics modulation by an electrical stimulation in two mechanically distinct cell types—human mesenchymal stem cells and osteoblasts. Application of a 2 V/cm direct current electric field resulted in approximately a twofold decrease in the cell elasticity and depleted intracellular ATP. Reduction in the ATP level led to inhibition of the linker proteins that are known to physically couple the cell membrane and cytoskeleton. The membrane separation from the cytoskeleton was confirmed by up to a twofold increase in the membrane tether length that was extracted from the cell membrane after an electrical stimulation. In comparison to human mesenchymal stem cells, the membrane-cytoskeleton attachment in osteoblasts was much stronger but, in response to the same electrical stimulation, the membrane detachment from the cytoskeleton was found to be more pronounced. The observed effects mediated by an electric field are cell type- and serum-dependent and can potentially be used for electrically assisted cell manipulation. An in-depth understanding and control of the mechanisms to regulate cell mechanics by external physical stimulus (e.g., electric field) may have great implications for stem cell-based tissue engineering and regenerative medicine.

Titushkin, Igor; Cho, Michael

2009-01-01

342

Statistical mechanics of granular systems  

NASA Astrophysics Data System (ADS)

From a first principles theory for the behavior of smooth granular systems, we derive the form for the instantaneous dissipative force acting between two grains. The present model, which is based on the classical harmonic crystal, reproduces the dependence of the kinetic energy dissipation on the grain deformation obtained by models that assume a viscoelastic behavior (without permanent plastic deformations) during the collision. We then derive kinetic equations for the rarified granular gas from the Fokker-Planck equation that describes the time evolution of the reduced distribution function for the translational granular degrees of freedom. We obtain the inelastic dissipation rate term and calculate the time evolution of the granular temperature for the homogeneous granular gas. We also derive kinetic equations for the non-homogeneous, rarified granular gas and obtain hydrodynamic equations for the system. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

Morgado, Welles A. M.

1997-11-01

343

HEMP emergency planning and operating procedures for electric power systems  

SciTech Connect

Investigations of the impact of high-altitude electromagnetic pulse (HEMP) on electric power systems and electrical equipment have revealed that HEMP creates both misoperation and failures. These events result from both the early time E[sub 1] (steep-front pulse) component and the late time E[sub 3] (geomagnetic perturbations) component of HEMP. In this report a HEMP event is viewed in terms of its marginal impact over classical power system disturbances by considering the unique properties and consequences of HEMP. This report focuses on system-wide electrical component failures and their potential consequences from HEMP. In particular, the effectiveness of planning and operating procedures for electric systems is evaluated while under the influence of HEMP. This assessment relies on published data and characterizes utilities using the North American Electric Reliability Council's regions and guidelines to model electric power system planning and operations. Key issues addressed by the report include how electric power systems are affected by HEMP and what actions electric utilities can initiate to reduce the consequences of HEMP. The report also reviews the salient features of earlier HEMP studies and projects, examines technology trends in the electric power industry which are affected by HEMP, characterizes the vulnerability of power systems to HEMP, and explores the capability of electric systems to recover from a HEMP event.

Reddoch, T.W.; Markel, L.C. (Electrotek Concepts, Inc., Knoxville, TN (United States))

1991-01-01

344

Pattern recognition for electric power system protection  

NASA Astrophysics Data System (ADS)

The objective of this research is to demonstrate pattern recognition tools such as decision trees (DTs) and neural networks that will improve and automate the design of relay protection functions in electric power systems. Protection functions that will benefit from the research include relay algorithms for high voltage transformer protection (TP) and for high impedance fault (HIF) detection. A methodology, which uses DTs and wavelet analysis to distinguish transformer internal faults from other conditions that are easily mistaken for internal faults, has been developed. Also, a DT based solution is proposed to discriminate HIFs from normal operations that may confuse relays. Both methods have been verified with simulation data generated by the Electromagnetic Transients Program. Compared with traditional methods, both show better performance. After being trained with a large number of carefully selected features, the desired DTs can obtain an accuracy of greater than 95%. Further, no special equipment is necessary; the DT-based controller only needs the standard relay input signals sampled at 1920 Hz. So far, no one has applied the same methodologies to solve these problems. Even though some future work with experimental data is needed to make the methods more convincing for utilities, the research has already shown that pattern recognition is a promising direction in developing power system protection algorithms.

Sheng, Yong

2002-11-01

345

Information and electrical power transmission system and method for vehicle  

Microsoft Academic Search

This patent describes an information and electrical power transmission system for a vehicle, comprising: a power supply circuit having an ignition keyswitch; a first group of electrical devices connected to the power supply circuit; a first information transmitting device connected to the first group of electrical devices and the power supply circuit. The information transmitting device has an information sending

M. Matsumoto; S. Akita; A. Kuno

1987-01-01

346

Electrical Systems. FOS: Fundamentals of Service. Fifth Edition.  

ERIC Educational Resources Information Center

This manual, which is part of a series on agricultural and industrial machinery, deals with electrical systems. Special attention is paid to electricity as it is commonly used on mobile machines. The following topics are covered in the individual chapters: electricity and how it works (current, voltage, and resistance; types of circuits;…

John Deere Co., Moline, IL.

347

Reliability evaluation of deregulated electric power systems for planning applications  

Microsoft Academic Search

In a deregulated electric power utility industry in which a competitive electricity market can influence system reliability, market risks cannot be ignored. This paper (1) proposes an analytical probabilistic model for reliability evaluation of competitive electricity markets and (2) develops a methodology for incorporating the market reliability problem into HLII reliability studies. A Markov state space diagram is employed to

A. Ehsani; A. M. Ranjbar; A. Jafari; M. Fotuhi-Firuzabad

2008-01-01

348

Quality management information system in manufacturing electrical machines  

Microsoft Academic Search

Electrical machines quality management includes three constituents, i.e. quality assurance, quality management and quality increase. There is a need to develop a matched information system for practical implementation of these problems during design and manufacturing. The quality of electrical machines is available by manufacturing accuracy to a large extent. The authors have developed accuracy theory of electrical machines which is

O. Muravlyova; O. Muravlyov

2001-01-01

349

A Mechanism for Action of Oscillating Electric Fields on Cells  

Microsoft Academic Search

The biological effects of electromagnetic fields have seriously concerned the scientific community and the public as well in the past decades as more and more evidence has accumulated about the hazardous consequences of so-called “electromagnetic pollution.” This theoretical model is based on the simple hypothesis that an oscillating external electric field will exert an oscillating force to each of the

Dimitris J. Panagopoulos; Niki Messini; Andreas Karabarbounis; Alexandros L. Philippetis; Lukas H. Margaritis

2000-01-01

350

Refrigeration Controls: Electrical & Mechanical; Appliance Repair 3: 9027.02.  

ERIC Educational Resources Information Center

This booklet outlines a course designed to equip major appliance service students with the fundamental knowledge and understanding of procedures, basic electrical circuitry, and nomenclatures of components necessary in successfully tracing a circuit and repairing or replacing a malfunctioning component. Course content includes goals, specific…

Dade County Public Schools, Miami, FL.

351

Coal mine electrical system evaluation. APL mine electrical system load-flow program. Task completion report  

Microsoft Academic Search

A guide to the development and use of an APL computer program for the analysis of load-flow problems is presented. The program is designed to provide an interactive method of load-flow study to improve underground coal mine electrical system design and safety. The theoretical basis for load-flow analysis is discussed, along with per-unit calculations which facilitate computation. Specific input\\/output, execution

L. A. Morley; F. C. Trutt; R. A. Rivell

1977-01-01

352

Reliability Mechanisms for Very Large Storage Systems  

Microsoft Academic Search

Reliability and availability are increasingly important in large-scale storage systems built from thousands of indi- vidual storage devices. Large systems must survive the fail- ure of individual components; in systems with thousands of disks, even infrequent failures are likely in some device. We focus on two types of errors: nonrecoverable read er- rors and drive failures. We discuss mechanisms for

Qin Xin; Ethan L. Miller; Thomas J. E. Schwarz; Darrell D. E. Long; Scott A. Brandt; Witold Litwin

2003-01-01

353

System for the co-production of electricity and hydrogen  

DOEpatents

Described herein is a system for the co-generation of hydrogen gas and electricity, wherein the proportion of hydrogen to electricity can be adjusted from 0% to 100%. The system integrates fuel cell technology for power generation with fuel-assisted steam-electrolysis. A hydrocarbon fuel, a reformed hydrocarbon fuel, or a partially reformed hydrocarbon fuel can be fed into the system.

Pham, Ai Quoc (San Jose, CA); Anderson, Brian Lee (Lodi, CA)

2007-10-02

354

Electrical response of heterogeneous systems with inclusions of arbitrary structure  

Microsoft Academic Search

We present an analytic approach to the electrical response of heterogeneous systems with inclusions of arbitrary structure. The exact local field acting on the inclusions, the multipole moments, and the effective dielectric function are obtained in terms of the polarization coefficients of the inclusions, the system configuration, and the applied electric field. We then provide the results for disordered systems

Liang Fu; Lorenzo Resca

1994-01-01

355

AUTOMOTIVE DIESEL MAINTENANCE 2. UNIT XX, TROUBLESHOOTING ELECTRICAL SYSTEMS.  

ERIC Educational Resources Information Center

THIS MODULE OF A 25-MODULE COURSE IS DESIGNED TO ACQUAINT THE TRAINEE WITH TROUBLESHOOTING PROCEDURES FOR DIESEL ENGINE ELECTRICAL SYSTEMS. TOPICS ARE (1) TROUBLESHOOTING ELECTRICAL SYSTEMS (INTRODUCTION), (2) TOOLS AND INSTRUMENTS FOR TROUBLESHOOTING, (3) THE BATTERY, (4) PERIODIC BATTERY SERVICING, (5) THE DC CHARGING SYSTEM, (6) PERIODIC…

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

356

Representing wind turbine electrical generating systems in fundamental frequency simulations  

Microsoft Academic Search

Increasing numbers of wind turbines are being erected. In the near future, they may start to influence the dynamics of electrical power systems by interacting with conventional generation equipment and with loads. The impact of wind turbines on the dynamics of electrical power systems therefore becomes an important subject, studied by means of power system dynamics simulations. Various types of

J. G. Slootweg; H. Polinder; W. L. Kling

2003-01-01

357

Spacecraft Electrical Power System (EPS) generic analysis tools and techniques  

NASA Technical Reports Server (NTRS)

An overview is provided of the analysis tools and techiques used in modeling the Space Station Freedom electrical power system, as well as future space vehicle power systems. The analysis capabilities of the Electrical Power System (EPS) are described and the EPS analysis tools are surveyed.

Morris, Gladys M.; Sheppard, Mark A.

1992-01-01

358

Electro-thermomigration as an electrical overstress failure mechanism  

NASA Astrophysics Data System (ADS)

A critical review of electrothermomigration as an EOS/ESD failure mechanism is presented. The paper focuses on the physical basis of the failure mechanism, the strength of the driving forces, and the effects of pulse attributes such as polarity on electrothermomigration. Recommendations or experiments to better understand this phenomenon are given.

Pierce, D. G.

1985-07-01

359

Spacelab Life Sciences-1 electrical diagnostic expert system  

NASA Technical Reports Server (NTRS)

The Spacelab Life Sciences-1 (SLS-1) Electrical Diagnostic (SLED) expert system is a continuous, real time knowledge-based system to monitor and diagnose electrical system problems in the Spacelab. After fault isolation, the SLED system provides corrective procedures and advice to the ground-based console operator. The SLED system updates its knowledge about the status of Spacelab every 3 seconds. The system supports multiprocessing of malfunctions and allows multiple failures to be handled simultaneously. Information which is readily available via a mouse click includes: general information about the system and each component, the electrical schematics, the recovery procedures of each malfunction, and an explanation of the diagnosis.

Kao, C. Y.; Morris, W. S.

1989-01-01

360

Stability assessment of electric power systems for ‘more electric’ aircraft  

Microsoft Academic Search

This paper presents a comprehensive assessment of small-signal stability for a ldquomore-electricrdquo aircraft power system consisting of a synchronous variable-frequency generator which supplies several power electronic controlled loads via an 18-pulse autotransformer rectifier unit (ATRU) for AC-DC conversion. Functional models for key power system components and loads are derived. Numerical tools employed for the automatic calculation of linearized equations and

Antonio Griffo; Jiabin Wang

2009-01-01

361

A Mechanism for Anonymous Credit Card Systems  

Microsoft Academic Search

This paper proposes a mechanism for anonymous credit card systems, in which each credit card holder can conceal individual transactions from the credit card company, while enabling the credit card company to calculate the total expenditures of transactions of individual card holders during specified periods, and to identify card holders who executed dishonest transactions. Based on three existing mechanisms, i.e.

Shinsuke Tamura; Tatsuro Yanase

2007-01-01

362

Archimedes 2 mechanical assembly planning system.  

National Technical Information Service (NTIS)

We describe the implementation and performance of Archimedes 2, an integrated mechanical assembly planning system. Archimedes 2 includes two planners, two assembly sequence animation facilities, and an associated robotic workcell. Both planners use full 3...

S. G. Kaufman R. H. Wilson R. E. Jones T. L. Calton A. L. Ames

1996-01-01

363

Advanced electric propulsion system concept for electric vehicles. Addendum 1. Voltage considerations  

SciTech Connect

Seventeen electric vehicle propulsion systems were originally studied to select two designs that best met cost and performance goals. Both systems have now been examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 kW-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated machine with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. Design changes in the battery pack voltage simply result in compensating changes in the motor configuration. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In this system the traction motor and power control unit must handle the peak power needed for acceleration. The traction motor can be designed to operate at specific battery voltages within a broad range, with little effect on motor efficiency, weight, or cost. The power control unit characteristics are effected by battery voltage, and the lowest voltages give the lowest efficiency, highest weight, and highest cost. In both systems, battery costs were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

Raynard, A.E.; Forbes, F.E.

1980-08-01

364

Transformers and the Electric Utility System  

ERIC Educational Resources Information Center

For electric energy to get from the generating station to a home, it must pass through a transformer, a device that can change voltage levels easily. This article describes how transformers work, covering the following topics: (1) the magnetism-electricity link; (2) transformer basics; (3) the energy seesaw; (4) the turns ratio rule; and (5)…

Roman, Harry T.

2005-01-01

365

Minimizing electric bearing currents in ASD systems  

Microsoft Academic Search

During recent years, an increase in bearing failures has been seen in ASD-fed electric motors, as well as in gearboxes, and other connected machinery, caused by electric current flow through such bearings. The theories presented in this paper focus on bearing currents in ASDs of the voltage source pulse width modulated (PWM) type, for use with AC induction motors, although

P. J. Link

1999-01-01

366

Illuminating Systems: Edison and Electrical Incandescence.  

ERIC Educational Resources Information Center

Traces the life and inventions of Thomas A. Edison up to the invention of electrical incandescent lighting in 1881. Focuses on the process that Edison followed in developing incandescent lighting, including financial aspects, other competitors in the field, and the eventual establishment of the Edison Electric Light Companies. (RW)

Sanford, Greg

1989-01-01

367

Electricity/Electronics Systems. Laboratory Activities.  

ERIC Educational Resources Information Center

This electricity/electronics guide provides teachers with learning activities for secondary students. Introductory materials include an instructional planning outline and worksheet, an outline of essential elements, a list of objectives, a course description, and a content outline. The guide contains 35 modules on the following topics: electrical…

Sutherland, Barbara, Ed.

368

Enhancing non-classicality in mechanical systems  

NASA Astrophysics Data System (ADS)

We study the effects of post-selection measurements on both the non-classicality of the state of a mechanical oscillator and the entanglement between two mechanical systems that are part of a distributed optomechanical network. We address the cases of both Gaussian and non-Gaussian measurements, identifying in which cases simple photon counting and Geiger-like measurements are effective in distilling a strongly non-classical mechanical state and enhancing the purely mechanical entanglement between two elements of the network.

Li, Jie; Gröblacher, Simon; Paternostro, Mauro

2013-03-01

369

Effects of annealing temperature on the electrical conductivity and mechanical property of CuTe alloys  

Microsoft Academic Search

The effects of annealing temperatre on the electrical conducitivity and mechanical property of Cu-Te alloys were studied via\\u000a an AG-10TA electronic universal machine, an SB2230 digital electric bridge, SEM, EDS and XPS. The results show the electrical\\u000a conductivity increases while the tensile strength fluctuates when the annealing temperature becomes higher because the recrystallization\\u000a occurs during the annealing process, leading to

Dachuan Zhu; Wen Huang; Mingzhao Song; Mingjing Tu

2007-01-01

370

Mechanical Energy Storage Technology Development for Electric and Hybrid Vehicle Applications.  

National Technical Information Service (NTIS)

The Department of Energy authorized the E and HV-MEST Project in September, 1977, to provide a focus for its efforts to develop mechanical energy storage technology for application to electric and hybrid vehicles. Technical management responsibility for t...

T. M. Barlow

1978-01-01

371

Reserve valuation in electric power systems  

NASA Astrophysics Data System (ADS)

Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

Ruiz, Pablo Ariel

372

Combined electro-thermo-mechanical model for life prediction of electrical insulating materials  

Microsoft Academic Search

A multistress model, appropriate for life prediction of electrical insulating materials subjected to electrical, thermal and mechanical stresses, is presented and compared with experimental life-test data relevant to HV generator stator insulation. The algorithm for the estimation of the large number of model parameters is presented and the goodness-of-fit of the model discussed

G. Mazzanti; G. C. Montanari; L. Simoni; M. B. Srinivas

1995-01-01

373

On the mechanism of electrical coupling between cells of early Xenopus embryos  

Microsoft Academic Search

Summary The mechanism of electrical coupling between cells of earlyXenopus embryos has been studied by examination of the nonjunctional membrane resistances and capacitances as a function of cleavage stage, the junctional and nonjunctional membrane resistances as functions of time during the first cleavage, and the electrical properties of the primitive blastocoel. The changes in membrane resitances and capacitances during the

R. A. DiCaprio; A. S. French; E. J. Sanders

1976-01-01

374

Evolution of the mechanisms of connection between neurons: Electrical, mixed, and chemical synapses  

Microsoft Academic Search

Investigation of the mechanisms of transmission of stimuli in synapses of isolated perfused spinal cord of cyclostomes, amphibia, reptiles, and mammals demonstrated that the ratio between electrical and chemical synapses decreased progressively in favor of the latter in the transition from primitive toward more highly developed forms. Electrical transmission was not detected in synapses of spinal cords of reptiles and

A. P. Shapovalov

1982-01-01

375

The optimal control of a homopolar motorgenerator using electrical brush mechanical load variation  

Microsoft Academic Search

Optimization of the transient performance of a homopolar motor-generator employed as a pulsed electrical power supply is investigated. Control of the mechanical force brush loads on both sets of electrical brushes located on the inside and outside radii of the rotor is studied in detail. Computation of the time varying optimal control energy loss and the total loss using constant

R. C. Swanson

1976-01-01

376

Power flow management strategies for a local DC Distribution System of More Electric Aircraft  

Microsoft Academic Search

The local DC Power Distribution System of More Electric Aircraft has to be able to sustain bidirectional power flow to and from electromechanical devices. Because the mechanical source (Turbine Engine) is unidirectional, some storage and dissipation systems are necessary to store or\\/and dissipate the returned energy to maintain the DC bus voltage to the reference value. Different power management strategies

He Zhang; Fabien MOLLET; Stefan BREBAN; Christophe SAUDEMONT; Benoît ROBYNS

2010-01-01

377

Simulation of electrical faults of three phase induction motor drive system  

Microsoft Academic Search

The simulation of a three-phase induction motor drive system is presented with emphasis on the electrical faults of the inverter and induction motor. Using the basic components of MATLAB SIMULINK toolboxes, the drive system is modeled. An induction motor with mechanical faults is modeled using the winding function method (WFM) and is integrated with the drive model using S-function. The

Zhongming Ye; Bin Wu

2001-01-01

378

AC Propulsion System for an Electric Vehicle. Phase 1, Final Report.  

National Technical Information Service (NTIS)

The object of this program was to develop and test a functional prototype of an ac propulsion system for an over-the-road electric vehicle. It was designed and fabricated from the ground up. The system consists of a two-speed, mechanically-shifted (hydrau...

S. Geppert

1981-01-01

379

Mechanical, Thermal and Electrical Resisitivity Properties of Thermoplastic Composites Filled with Carbon Fibers and Carbon Particles  

Microsoft Academic Search

Composites consisting of carbon fibers (CF) and carbon particles (CP) in polypropylene (PP) matrix were melt-compounded. Composites\\u000a were analyzed for their mechanical, electrical and thermal properties. Results indicate that the addition of these fillers\\u000a improved the mechanical properties of the composites. Thermal conductivity was enhanced as the concentration of fillers was\\u000a increased. Carbon fibers render the composites electrically conductive so

Anjum Saleem; Lars Frormann; Azhar Iqbal

2007-01-01

380

Design of Electrical\\/Mechanical Hybrid 4Redundancy Brushless DC Torque Motor  

Microsoft Academic Search

This article presents a novel electrical\\/mechanical hybrid 4-redundancy brushless DC torque motor (BLDCM), which has found applications in direct drive actuators (DDA) of aerial vehicles. This motor is characteristic of electrical\\/mechanical hybrid 4-redundancy by securing two stators along with two rotors on the same shaft. Each stator contains two sets of windings embedded in separated slots. Furthermore, compared to the

Guo Hong; Wang Wei; Xing Wei; Li Yanming

2010-01-01

381

Study on Mechanical, Thermal and Electrical Characterizations of Nano-SiC\\/Epoxy Composites  

Microsoft Academic Search

This report covers the results of a study on evaluating the effect of nano-SiC particles on mechanical, thermal and electrical properties of epoxy by lap shear, TGA, DSC and electrical tests. Epoxy composites filled with micro-SiC particles were also studied for comparison. The mechanisms of performance improvement were discussed in detail. The results showed that with identical loading, silane treated

Tianle Zhou; Xin Wang; Mingyuan Gu; Dangsheng Xiong

2009-01-01

382

Measurement of small mechanical vibrations of brain tissue exposed to extremely-low-frequency electric fields  

Microsoft Academic Search

Electromagnetic fields can interact with biological tissue both electrically and mechanically. This study investigated the mechanical interaction between brain tissue and an extremely-low-frequency (ELF) electric field by measuring the resultant vibrational amplitude. The exposure cell is a section of X-band waveguide that was modified by the addition of a center conductor to form a small TEM cell within the waveguide

R. J. Spiegel; J. S. Ali; J. F. Peoples; W. T. Joines

1986-01-01

383

Regularization of chaos by noise in electrically driven nanowire systems  

NASA Astrophysics Data System (ADS)

The electrically driven nanowire systems are of great importance to nanoscience and engineering. Due to strong nonlinearity, chaos can arise, but in many applications it is desirable to suppress chaos. The intrinsically high-dimensional nature of the system prevents application of the conventional method of controlling chaos. Remarkably, we find that the phenomenon of coherence resonance, which has been well documented but for low-dimensional chaotic systems, can occur in the nanowire system that mathematically is described by two coupled nonlinear partial differential equations, subject to periodic driving and noise. Especially, we find that, when the nanowire is in either the weakly chaotic or the extensively chaotic regime, an optimal level of noise can significantly enhance the regularity of the oscillations. This result is robust because it holds regardless of whether noise is white or colored, and of whether the stochastic drivings in the two independent directions transverse to the nanowire are correlated or independent of each other. Noise can thus regularize chaotic oscillations through the mechanism of coherence resonance in the nanowire system. More generally, we posit that noise can provide a practical way to harness chaos in nanoscale systems.

Hessari, Peyman; Do, Younghae; Lai, Ying-Cheng; Chae, Junseok; Park, Cheol Woo; Lee, GyuWon

2014-04-01

384

Modeling Mechanical Subsystems of the Hybrid Electric Transmission  

NSDL National Science Digital Library

This lab is part of the course âIntro to Mechatronicsâ at Lawrence Technological University and was developed through seed funding from the CAAT. In the lab students are introduced to the use of planetary gearsets and their application to hybrid electric vehicle (HEV) transmissions. Students are first familiarized with the planetary gearset equation and then use MAT Lab software to visualize the relationship between input data and the resulting output torque and speed through the gear set. All MAT Lab files are included.

University, Lawrence T.

385

Mechanical system reliability for long life space systems  

NASA Technical Reports Server (NTRS)

The creation of a compendium of mechanical limit states was undertaken in order to provide a reference base for the application of first-order reliability methods to mechanical systems in the context of the development of a system level design methodology. The compendium was conceived as a reference source specific to the problem of developing the noted design methodology, and not an exhaustive or exclusive compilation of mechanical limit states. The compendium is not intended to be a handbook of mechanical limit states for general use. The compendium provides a diverse set of limit-state relationships for use in demonstrating the application of probabilistic reliability methods to mechanical systems. The compendium is to be used in the reliability analysis of moderately complex mechanical systems.

Kowal, Michael T.

1994-01-01

386

Project - Centered Modules in Mechanical Systems Engineering  

Microsoft Academic Search

This paper presents a description of hardware and software modules used in dynamic systems an d controls and related courses in manufacturing systems, mechatronics, robotics, and automation in the Mechanical Engineering curriculum. The modules span across a common set of equipment and are designed for varying degrees of depth, depending on use in a given course. The objective is to

Daniel J. Cox

387

Identification of a mechanical vibration system  

NASA Technical Reports Server (NTRS)

The actual values of the parameters of a precision instrument assembly vibration system are determined according to experimental amplitude-frequency characteristics. The assembly is considered as a complex mechanical vibrating system, consisting of elements with concentrated and distributed parameters. A calculation procedure was compiled.

Korablev, S. S.; Filatov, Y. Y.; Shapin, V. I.

1973-01-01

388

Small Wind Electric Systems: A Kansas Consumer's Guide.  

National Technical Information Service (NTIS)

The Kansas Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wi...

2001-01-01

389

Small Wind Electric Systems: A Vermont Consumer's Guide.  

National Technical Information Service (NTIS)

The Vermont Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their w...

2001-01-01

390

Harmonic disturbances in electric traction system overhead lines  

Microsoft Academic Search

The paper presents the disturbance spectrum generated by electric traction units in different operating conditions. In particular, an experimental data set is used to analyze the electric systems for transportation currently in use in Italy, based on static power conversion stations and DC supply feeders are present. In these traction systems the train supply voltage has harmonic spectrum characterized by

Paolo Pinato; Dario Zaninelli

2002-01-01

391

Analysis method for non-schedulable generation in electric systems  

Microsoft Academic Search

Elements of a cost-benefit analysis of the modification of electrical energy utility system in order to accommodate the introduction of solar and wind electric systems output are presented. A perturbation approach is adopted for the study in order to characterize the average utility load duration, the generation duration, and the kinds of generators using statistical averages, deviations, and variances. The

P. M. Moretti; B. W. Jones

1982-01-01

392

Electromagnetic interference assessment of an ion drive electric propulsion system  

NASA Technical Reports Server (NTRS)

An electric propulsion thrust system has the capability of providing a high specific impulse for long duration scientific missions in space. The EMI from the elements of an ion engine was characterized. The compatibility of ion drive electric propulsion systems with typical interplanetary spacecraft engineering was predicted.

Whittlesey, A. C.

1981-01-01

393

Diagnosing Faults in Electrical Power Systems of Spacecraft and Aircraft  

Microsoft Academic Search

Electrical power systems play a critical role in spacecraft and aircraft. This paper discusses our development of a diagnos- tic capability for an electrical power system testbed, ADAPT, using probabilistic techniques. In the context of ADAPT, we present two challenges, regarding modelling and real-time performance, often encountered in real-world diagnostic ap- plications. To meet the modelling challenge, we discuss our

Ole J. Mengshoel; Adnan Darwiche; Keith Cascio; Mark Chavira; Scott Poll; N. Serdar Uckun

2008-01-01

394

49 CFR 570.58 - Electric brake system.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Electric brake system. 570.58 ...DEPARTMENT OF TRANSPORTATION VEHICLE IN USE INSPECTION STANDARDS Vehicles With GVWR of More Than 10,000 Pounds § 570.58 Electric brake system. (a)...

2013-10-01

395

A Testing System for Diagnosing Misconceptions in DC Electric Circuits.  

ERIC Educational Resources Information Center

Outlines a test-based diagnosis system for misconceptions in DC electric circuits and its three parts: problem library, problem selector and diagnoser. Discusses misconception discrimination and diagnosis theories, and reports the system supports satisfactory diagnosis. Includes an analysis of nine student misconceptions about electrical circuits…

Chang, Kuo-En; Liu, Sei-Hua; Chen, Sei-Wang

1998-01-01

396

Small Wind Electric Systems: A Maryland Consumer's Guide.  

National Technical Information Service (NTIS)

Small Wind Electric Systems: A Maryland Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind re...

2006-01-01

397

Precise time and time interval applications to electric power systems  

Microsoft Academic Search

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on measuring power system frequency consistently in many locations. The internal oscillators in the widely dispersed frequency measuring units must be syntonized. Elaborate

Robert E. Wilson

1992-01-01

398

Probabilistic security analysis of shipboard DC zonal electrical distribution systems  

Microsoft Academic Search

Due to significant gains in terms of survivability, weight, manning, and cost obtained from DC zonal electrical distribution systems (DC ZEDS), various practical applications of DC ZEDS to shipboard electric power systems are expected in the foreseeing future. How to ensure whether shipboard DC ZEDS under different power outage events is secure becomes important for real-time operation and planning of

Chun-Lien Su; Chun-Teng Yeh

2008-01-01

399

Results of an electrical power system fault study (CDDF)  

NASA Technical Reports Server (NTRS)

This report gives the results of an electrical power system fault study which has been conducted over the last 2 and one-half years. First, the results of the literature search into electrical power system faults in space and terrestrial power system applications are reported. A description of the intended implementations of the power system faults into the Large Autonomous Spacecraft Electrical Power System (LASEPS) breadboard is then presented. Then, the actual implementation of the faults into the breadboard is discussed along with a discussion describing the LASEPS breadboard. Finally, the results of the injected faults and breadboard failures are discussed.

Dugal-Whitehead, N. R.; Johnson, Y. B.

1993-01-01

400

Evaluation of Coal Mine Electrical System Safety.  

National Technical Information Service (NTIS)

This report contains four principal chapters covering accomplishments in the mine electrical safety research areas of continuous monitoring, battery and battery-charging safety, and computer modeling. Highlights of the work are summarized in the last repo...

L. A. Morley F. C. Trutt J. L. Kohler

1978-01-01

401

Electrical Protection of Tactical Communication Systems.  

National Technical Information Service (NTIS)

The manual covers the subject of electrical protection with sufficient thoroughness to enable the communications engineer to evaluate the probable extent of a protection problem and to develop protection measures that are not only effective but also in ec...

D. W. Bodie J. B. Hays

1964-01-01

402

The thermal and electrical properties of nano-silicon dioxide filled epoxy systems for use in high voltage insulation  

Microsoft Academic Search

Epoxy resins have proven to be an excellent insulation system in many application due to their excellent mechanical, thermal and electrical properties. This paper details an investigation into micro and nano silicon dioxide (SD and NSD respectively) filled epoxy systems and the resulting thermal and electrical properties of the composite. The effect of addition of the fillers relative to their

Martin Reading; Zhiqiang Xu; Alun S. Vaughan; Paul L. Lewin

2011-01-01

403

Assessment of Distributed Photovoltaic Electric-Power Systems. Final Report.  

National Technical Information Service (NTIS)

The purpose of this study was to develop a methodology for assessing the potential impacts of distributed photovoltaic (PV) systems on electric utility systems, including subtransmission and distribution networks, and to apply that methodology to several ...

R. W. Neal P. F. DeDuck R. N. Marshall

1982-01-01

404

Systems and methods for an integrated electrical sub-system powered by wind energy  

DOEpatents

Various embodiments relate to systems and methods related to an integrated electrically-powered sub-system and wind power system including a wind power source, an electrically-powered sub-system coupled to and at least partially powered by the wind power source, the electrically-powered sub-system being coupled to the wind power source through power converters, and a supervisory controller coupled to the wind power source and the electrically-powered sub-system to monitor and manage the integrated electrically-powered sub-system and wind power system.

Liu, Yan (Ballston Lake, NY) [Ballston Lake, NY; Garces, Luis Jose (Niskayuna, NY) [Niskayuna, NY

2008-06-24

405

Statistical mechanics of polymer systems. Final  

SciTech Connect

Work on computer simulation of polymer dynamics and the statistical mechanics of quenched systems carried out over seven years with the support of this grant is reviewed. The computer simulation work has focused on elucidation the roles of the excluded volume and the nearest-neighbor attractive interactions in the dynamics of polymers. To study quenched systems we have applied the formalism suggested long ago by Mazo to two model systems and found qualitative agreement with the properties of real glasses.

Kovac, J.

1993-06-01

406

The electron Echo 6 mechanical deployment systems  

NASA Technical Reports Server (NTRS)

The Echo 6 sounding rocket payload was flown on a Terrier boosted Black Brant vehicle on March 30, 1983. The experiment requirements resulted in the new design of a rocket propelled Throw Away Detector System (TADS) with onboard Doppler radar, a free-flyer forward experiment designated the Plasma Diagnostic Package (PDP), and numerous other basic systems. The design, developmental testing, and flight preparations of the payload and the mechanical deployment systems are described.

Meyers, S. C.; Steffen, J. E.; Malcolm, P. R.; Winckler, J. R.

1984-01-01

407

A simple method to characterize the electrical and mechanical properties of micro-fibres  

NASA Astrophysics Data System (ADS)

A procedure to characterize the electrical and mechanical properties of micro-fibres is presented here. As the required equipment can be found in many teaching laboratories, it can be carried out by physics and mechanical/electrical engineering students. The electrical resistivity, mass density and Young's modulus of carbon micro-fibres have been determined using this procedure, obtaining values in very good agreement with the reference values. Young's modulus has been obtained by measuring the resonance frequency of carbon fibre-based cantilevers. In this way, one can avoid common approaches based on tensile or bending tests which are difficult to implement for microscale materials. Despite the simplicity of the experiments proposed here, they can be used to trigger in the students interest regarding the electrical and mechanical properties of microscale materials.

Castellanos-Gomez, A.

2013-11-01

408

Mechanical properties of thermal protection system materials  

Microsoft Academic Search

An experimental study was conducted to measure the mechanical properties of the Thermal Protection System (TPS) materials used for the Space Shuttle. Three types of TPS materials (LI-900, LI-2200, and FRCI-12) were tested in 'in-plane' and 'out-of-plane' orientations. Four types of quasi-static mechanical tests (uniaxial tension, uniaxial compression, uniaxial strain, and shear) were performed under low (10⁻⁴ to 10⁻³\\/s) and

Robert Douglas Hardy; David R. Bronowski; Moo Yul Lee; John H. Hofer

2005-01-01

409

Natural rubber electrical conduction mechanism in high and low electric fields  

Microsoft Academic Search

The services in energized lines become more and more indispensable and its efficiency depends on the electrical worker who is involved in such activity. The efficiency of such work highly depends on the worker's safety, which is protected by tools such as gloves, sleeves, blankets and flexible coverings among other manufactured natural-rubber goods. Use, storage and maintenance of these tools

E. L. Kowalski; R. Robert; J. Tomioka; Teixeira Junior; J. C. Tosin; R. E. Clerise; O. E. Filho

2005-01-01

410

Impact of electric vehicle loads on electric power distribution systems  

NASA Astrophysics Data System (ADS)

The voltages and currents on four distribution sites (FPLsb-1 to FPLsb-4) have been monitored. The load behavior with and without the EV load has been recorded. By performing laboratory tests on the GMC EV1 charger charging a fully discharged battery, the characteristics of the charger have been determined. The harmonic spectrum of the transformer current charging a fully discharged battery has been determined. The snap shots of the current and voltage waveforms have been recorded and studied. Based on the laboratory data a computer model of the charger and the distribution system has been developed. Comparing the simulation results to the laboratory results and the field data the simulation results have been validated. The simulated currents are roughly 4 to 10% away from the field recorded currents, in their magnitude and distortion. Based on the field data, laboratory results and the simulation results the derating of the distribution transformer has been calculated. The two methods suggested for the calculation of derating have been presented and compared. The maximum and minimum limits of derating have been suggested. Using the first method the maximum derating is 20% and the minimum value is 99%. Using the modified method the derating remains close to 99% throughout the charging cycle. (11 must be noted here, that a derating to 20% means that the transformer can safely handle only 20% of its full rated load. Likewise a derating to 99% means that the transformer can handle 99% of its full rated capacity. Thus, a transformer derated to 20% is highly derated and a transformer derated to 99% is slightly derated.) After establishing the reliability of the simulation, by comparing the simulation results with the field data and laboratory results, a charging scenario with shorter charging times (45 minutes and 1.2 hours) has been simulated. The distribution transformer derating corresponding to these short-charging times has been calculated and presented. Furthermore, recommended scope for further research has been suggested which among other things, involves validating the derating formula for distribution transformers.

Buchh, Tariq Aslam

411

Hardware-in-the-loop simulation of electric vehicle traction systems using Energetic Macroscopic Representation  

Microsoft Academic Search

A hardware-in-the-loop (HIL) simulation of an electric vehicle traction system is developed for experimental validations of electrical drives. Energetic macroscopic representation is used to organize the numerous blocks required. A classical 2-driven-wheels traction is studied with an induction machine. The HIL is based on a controlled DC drive, which imposes the same behavior of the mechanical power train to the

A. Bouscayrol; W. Lhomme; P. Delarue; B. Lemaire-Semail; S. Aksas

2006-01-01

412

Lunar Dust Chemical, Electrical, and Mechanical Reactivity: Simulation and Characterization  

NASA Technical Reports Server (NTRS)

Lunar dust is recognized to be a highly reactive material in its native state. Many, if not all Constellation systems will be affected by its adhesion, abrasion, and reactivity. A critical requirement to develop successful strategies for dealing with lunar dust and designing tolerant systems will be to produce similar material for ground-based testing.

VanderWal, Randy L.

2008-01-01

413

Feeder automation for an electric power distribution system  

US Patent & Trademark Office Database

A soft PLC technology based computer-implemented method includes updating a system configuration incidence matrix for an electric power distribution system based on both a depth-first search of a connectivity matrix for the electric power distribution system and information about the electric power distribution system, wherein the information includes at least status information about one or more switches of the electric power distribution system. The method further includes detecting a fault in the system based on the incidence matrix. The method further includes generating isolation control logic based on the incidence matrix and isolating the fault based on isolation control logic. The method further includes generating restoration control logic based on a breadth-first search of the incidence matrix and restoring the system based on the restoration control logic.

2012-02-21

414

Environmental and economic comparison of cooling-system designs for steam-electric power plants  

Microsoft Academic Search

The selection of waste heat rejection systems for steam-electric power plants involves a trade-off among environmental, energy and water conservation, and economic factors. This study compares four general types of cooling systems on the basis of these factors. The cooling systems chosen for study are: once-through systems including surface canals and submerged multiport diffusers; shallow closed cycle cooling ponds; mechanical

K. F. Najjar; J. J. Shaw; E. E. Adams; G. H. Jirka; D. R. F. Harleman

1979-01-01

415

Effects of surfactant treatment on mechanical and electrical properties of CNT\\/epoxy nanocomposites  

Microsoft Academic Search

Surfactant has been successfully applied to enhance the dispersion of carbon nanotubes (CNTs) in polymer and the properties of nanocomposite. CNTs were treated with a nonionic surfactant Triton X-100, and its effects on dispersion state, surface chemistry, structure and morphology of CNTs, as well as on the thermomechanical, mechanical and electrical properties of CNT\\/epoxy nanocomposites were evaluated. The mechanical properties

Yan Geng; Ming Yang Liu; Jing Li; Xiao Mei Shi; Jang Kyo Kim

2008-01-01

416

Electrical and Mechanical Properties of Some Butadiene Rubber Composites in the Vicinity of the Percolation Threshold  

Microsoft Academic Search

The electrical and mechanical properties of NBR\\/SBR blends with different compositions were studied before the addition of carbon black. The increase in permittivity ?? and dielectric loss ?? noticed by increasing NBR content is due to the increase in C ? N dipoles. The mechanical properties which include tensile and elongation at yield and rupture are also found to be increased. This

Abeer S. A. Reffaee; D. E. El Nashar; S. L. Abd-El-Messieh; K. N. Abd-El Nour

2007-01-01

417

Procedure for the numerical computation of mechanical vibrations in electrical machines  

Microsoft Academic Search

The authors describe a way to calculate the mechanical vibrations of the stator and case in the two-dimensional modeling of electrical machines. The mechanical vibrations are the result of the magnetic forces acting on the surfaces of the stator. The vibration calculation consists of three steps: (1) finite element method calculation of the magnetic field; (2) local force density calculation

G. Henneberger; P. K. Sattler; W. Hadrys; D. Shen

1992-01-01

418

GENERAL: Noether symmetries of discrete mechanico-electrical systems  

NASA Astrophysics Data System (ADS)

This paper focuses on studying Noether symmetries and conservation laws of the discrete mechanico-electrical systems with the nonconservative and the dissipative forces. Based on the invariance of discrete Hamilton action of the systems under the infinitesimal transformation with respect to the generalized coordinates, the generalized electrical quantities and time, it presents the discrete analogue of variational principle, the discrete analogue of Lagrange-Maxwell equations, the discrete analogue of Noether theorems for Lagrange-Maxwell and Lagrange mechanico-electrical systems. Also, the discrete Noether operator identity and the discrete Noether-type conservation laws are obtained for these systems. An actual example is given to illustrate these results.

Fu, Jing-Li; Chen, Ben-Yong; Xie, Feng-Ping

2008-12-01

419

A complete electrical hazard classification system and its application  

SciTech Connect

The Standard for Electrical Safety in the Workplace, NFPA 70E, and relevant OSHA electrical safety standards evolved to address the hazards of 60-Hz power that are faced primarily by electricians, linemen, and others performing facility and utility work. This leaves a substantial gap in the management of electrical hazards in Research and Development (R&D) and specialized high voltage and high power equipment. Examples include lasers, accelerators, capacitor banks, electroplating systems, induction and dielectric heating systems, etc. Although all such systems are fed by 50/60 Hz alternating current (ac) power, we find substantial use of direct current (dc) electrical energy, and the use of capacitors, inductors, batteries, and radiofrequency (RF) power. The electrical hazards of these forms of electricity and their systems are different than for 50160 Hz power. Over the past 10 years there has been an effort to develop a method of classifying all of the electrical hazards found in all types of R&D and utilization equipment. Examples of the variation of these hazards from NFPA 70E include (a) high voltage can be harmless, if the available current is sufficiently low, (b) low voltage can be harmful if the available current/power is high, (c) high voltage capacitor hazards are unique and include severe reflex action, affects on the heart, and tissue damage, and (d) arc flash hazard analysis for dc and capacitor systems are not provided in existing standards. This work has led to a comprehensive electrical hazard classification system that is based on various research conducted over the past 100 years, on analysis of such systems in R&D, and on decades of experience. Initially, national electrical safety codes required the qualified worker only to know the source voltage to determine the shock hazard. Later, as arc flash hazards were understood, the fault current and clearing time were needed. These items are still insufficient to fully characterize all types of electrical hazards. The new comprehensive electrical hazard classification system uses a combination of voltage, shock current available, fault current available, power, energy, and waveform to classify all forms of electrical hazards. Based on this electrical hazard classification system, many new tools have been developed, including (a) work controls for these hazards, (b) better selection of PPE for R&D work, (c) improved training, and (d) a new Severity Ranking Tool that is used to rank electrical accidents and incidents with various forms of electrical energy.

Gordon, Lloyd B [Los Alamos National Laboratory; Cartelli, Laura [Los Alamos National Laboratory

2009-01-01

420

Electrical stability of metal/low dielectric constant material systems  

NASA Astrophysics Data System (ADS)

In order to boost the performance of future generation silicon integrated circuits, new materials with lower dielectric constant (kappa) are under evaluation to replace traditional SiO2 as on-chip inter-layer dielectrics (ILDs). The goal of this thesis has been to investigate the intrinsic electrical stability and metal penetration resistance of a variety of low kappa materials: fluorinated silica glass (FSG), polyparaxylylene-N (parylene-N), polyarylether (PAE) and hybrid organosiloxane polymer (HOSP). Emphasis was placed on fundamental understanding of the factors controlling the electrical properties of different metal/low kappa dielectric systems. Traditionally, metal ion penetration is studied using Bias Temperature Stressing (BTS) with Capacitance-Voltage (C-V) measurement. In this work, an alternative technique, Triangular Voltage Sweep (TVS), was also adopted to provide insight into metal penetration behavior. Surprisingly, aluminum ion penetration into oxygen containing polymers such as PAE and HOSP was detected, and was in contrast to the stability of the Al/SiO2 system. Platinum was demonstrated as a viable control for metal drift studies in such polymers, as no platinum ion penetration was detected. Among the blanket dielectrics, the number of copper ions detected was lowest in HOSP, demonstrating its promise for ILD applications. Experimentation with a variety of metals led to the result that ion penetration behavior in HOSP showed the trend Pt < Cu < Ta < Al. This trend indicated that metal penetration increases with metal ionization and oxidation tendency. Plasma modification of HOSP by converting its surface to a thin intrinsic dielectric barrier resembling SiO2 dramatically reduced aluminum ion penetration in HOSP. Surface modification is therefore a powerful strategy to realize the future requirement of ultra-thin barriers. The impact of on-chip integration on electrical stability was also studied. Copper ions were detected along fast diffusion paths in an integrated FSG due to barrier failure and processing-related copper contamination. The results from all the various novel dielectrics clearly establish that metal/dielectric interactions induced by thermal and electrical treatments are very unlike those observed in metal/SiO2 systems. Careful evaluation is required to elucidate the metal penetration mechanism as it is influenced by surface chemistry, metal ionization and chemical reactivity, and bulk dielectric structure or composition.

Mallikarjunan, Anupama

421

Electrically conductive and mechanically elastic titanium nitride ceramic microsprings.  

PubMed

The structural and functional characterizations of titanium nitride (TiN) advanced ceramic microsprings (CMSs), with a coil diameter of several micrometers and synthesized by chemical vapor deposition (CVD) were investigated by microscopy techniques. The CMSs were sufficiently mechanically elastic for extension to more than 1.3 times their original size, and they spontaneously contracted to their original state on releasing the tension. To explore their application to a microdevice, a method of manufacturing TiN-CMS microcircuit elements was developed. The I-V plots of the elements indicated that the CMSs were as conductive as metals. PMID:24738385

Yang, Shaoming; Chen, Xiuqin; Yamamoto, Kazuo; Iitake, Masanori; Nishio-Hamane, D; Sakai, Hideki; Abe, Masahiko

2014-06-01

422

75 FR 72909 - Revision to Electric Reliability Organization Definition of Bulk Electric System  

Federal Register 2010, 2011, 2012, 2013

...order to mitigate an unanticipated clockwise flow around Lake Erie, and that classification of lower voltage facilities as part...200 kV bulk electric system threshold reflects the usage and history of the Western Interconnection.\\143\\ They further...

2010-11-26

423

75 FR 14097 - Revision to Electric Reliability Organization Definition of Bulk Electric System  

Federal Register 2010, 2011, 2012, 2013

...definition of bulk electric system in the NERC Glossary of Terms Used in Reliability Standards (NERC Glossary); however, as permitted by that definition...contained in Commission-approved NERC Glossary and has determined that the...

2010-03-24

424

Mechanism(s) of Electricity Production by Shewanella and other Microbes: Understanding and Optimization.  

National Technical Information Service (NTIS)

In the five years of this MURI program, we have made major advances in several areas, including: (1) power production optimization; (2) MFC design; (3) identification of the genes coding for the proteins involved with electricity production by Shewanella ...

A. Luettge, K. H. Nealson, M. El-Naggar, S. Finkel, Y. Gorby

2013-01-01

425

Mechanism(s) of Electricity Production by Shewanella and Other Microbes: Understanding and Optimization.  

National Technical Information Service (NTIS)

In the five years of this MURI program, we have made major advances in several areas, including: (1) power production optimization; (2) MFC design; (3) identification of the genes coding for the proteins involved with electricity production by Shewanella ...

A. Luettge, K. H. Nealson, M. El-Naggar, S. Finkel, Y. Gorby

2012-01-01

426

An EMC study of an electrical powertrain for transportation systems  

NASA Astrophysics Data System (ADS)

There are many reasons, why electric drive systems will be used in future more frequently in transportation systems. The electrification allows a flexible use of different energy sources and thus creates a greater independence from fossil energy. However, electric drive systems are a challenge for the manufacturers of transportation systems. The electrical powertrain can not only be exposed to interferences, it may also emit interferences into components and communication cables in the vicinity. This can be a high risk for the drive system and for the passengers. For that reason, an EMC study of an electrical powertrain for transportation systems is presented. There the interference at the unshielded high-voltage cable (HV-cable) is characterized. The analysis of the influence of position variation of the communication cable with respect to the unshielded HV-cables is one main aspect. Different optimizations have been added to the test setup.

Chand, B.; Hähre, K.; Keghie, J.; Dickmann, S.

2012-09-01

427

Electrical and kinematic structure of an Oklahoma mesoscale convective system  

NASA Technical Reports Server (NTRS)

The case study examines the dynamics and kinematics of a mesoscale convective system (MCS) by comparing its meteorological parameters with in situ electrical measurements. Conventional MCS characteristics are reported including a rear inflow jet, wake low, and a bipolar cloud-to-ground pattern, but some nonclassical conditions are also reported. Horizontally long cloud-to-ground electrical strikes are noted which demonstrate that cloud-to-ground electrical data alone cannot entirely characterize stratiform electrification in MCSs.

Hunter, Steven M.; Schuur, Terry J.; Marshall, Thomas C.; Rust, W. D.

1990-01-01

428

Multi-Objective Design Optimisation of Submarine Electric Drive Systems  

Microsoft Academic Search

The design of an integrated electric propulsion (IEP) system is considered for naval submarine propulsion. A multi-objective genetic algorithm is used to explore potential IEP topologies and designs, including direct-drive, geared-drive and hybrid steam-turbine\\/electric drive. Typical submarine mission scenarios are simulated and trade-offs in performance are investigated. Compromises in propeller and electric motor efficiency are found, as are large discrepancies

Benjamin A. Skinner; Patrick R. Palmer; Geoffrey T. Parks

2007-01-01

429

Unraveling Mechanisms Regulating Systemic Iron Homeostasis  

PubMed Central

Systemic iron balance must be tightly regulated to prevent the deleterious effects of iron deficiency and iron overload. Hepcidin, a circulating hormone that is synthesized by the liver, has emerged as a key regulator of systemic iron homeostasis. Hepcidin inhibits the absorption of dietary iron from the intestine as well as the release of iron derived from red blood cells from macrophages; thus, variation in hepcidin levels modifies the total amount of iron stored in the body as well as the availability of iron for erythropoiesis. The production of hepcidin by the liver is modulated by multiple physiological stimuli, including iron loading, inflammation, and erythropoietic activity. Investigation of the functions of the gene products mutated in inherited iron disorders using tissue culture systems and animal models has provided valuable insights into the mechanisms by which these hepcidin responses are mediated. This review focuses on recent advances in our understanding of the molecular mechanisms underlying the regulation of systemic iron homeostasis.

Finberg, Karin E.

2013-01-01

430

Mine Electrical Power Systems. Transients Protection, Reliability Investigation, and Safety Testing of Mine Electrical Power Systems. Volume III--Optimal Design of Mine Electrical Power Systems.  

National Technical Information Service (NTIS)

This report describes the analysis tools developed at West Virginia University that can be implemented to optimally design coal mine electrical systems. The basic analytical tools for all power systems are the load-flow and short-circuit analysis. Well kn...

M. M. Hassan E. K. Stanek

1979-01-01

431

Compression of PZT-5H piezoelectric ceramic at constant electric field: investigation of energy absorption mechanism  

NASA Astrophysics Data System (ADS)

This paper presents an experimental and analytical investigation into the mechanical behavior of PZT-5H piezoelectric ceramic. The materia is subjected to cyclic uniaxial compressive stress at a constant electric field bias. The damping characteristics such as fraction of energy absorbed and elastic modulus are evaluated as a function of bias electric field. Increasing the positive electric field increases the specific damping and decreases the elastic modulus. The trend is reversed when the electric field becomes sufficiently high to inhibit the domain wall motion by the mechanical stresses. Measured specific damping values vary form 0.18 to 0.46 depending on the stress amplitude and bias electric field. The corresponding secant modulus varies from 79 to 24 Gpz. The optimum electric field values increase as the stress amplitude increases because the positive electric field and the compressive stress counteract each other in terms of domain wall motion. An analytical model shows that the material's response is proportional to the volume fraction of the domains available for switching and the domain wall pressure difference between positive electric field and compressive stress.

Chaplya, Pavel M.; Carman, Gregory P.

2002-07-01

432

Advanced electric propulsion system concept for electric vehicles. Addendum 1. Voltage considerations  

Microsoft Academic Search

Seventeen electric vehicle propulsion systems were originally studied to select two designs that best met cost and performance goals. Both systems have now been examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 kW-hr. The highest battery

A. E. Raynard; F. E. Forbes

1980-01-01

433

Basics of a Solar Electric System: Better Buildings Series Solar Electric Fact Sheet  

SciTech Connect

Today's solar technologies are more efficient and versatile than ever before, adding to the appeal of an already desirable energy source. This fact sheet provides information on the basics of a solar electric system, including components of a system, how to choose solar modules, and how to choose a solar system.

Not Available

2002-07-01

434

Supermarket refrigeration assessment for the New England Electric System  

SciTech Connect

The Electric Power Research Institute (EPRI) has undertaken a project to assess the impact of energy efficient supermarket refrigeration on the electric capacity requirements of the New England Electric System (NEES) service territories. The leading supermarket chains in the NEES service territories were contacted and the number of supermarkets and the types of refrigeration systems employed were established. Estimates were then made of the potential demand and energy savings that NEES and the supermarkets could realize if energy efficient refrigeration systems were employed. On the basis of this analysis, possible incentives to accelerate the implementation of energy efficient refrigeration equipment in NEES service territories were recommended. 4 refs., 10 figs., 27 tabs.

Tsaros, T.L.; Walker, D.H. (Foster-Miller, Inc., Waltham, MA (United States))

1991-07-01

435

46 CFR 108.407 - Detectors for electric fire detection system.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Detectors for electric fire detection system. 108.407...Systems § 108.407 Detectors for electric fire detection system. (a) Each detector in an electric fire detection system must be located...

2013-10-01

436

46 CFR 113.35-5 - Electric engine order telegraph systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Electric engine order telegraph systems. 113...Order Telegraph Systems § 113.35-5 Electric engine order telegraph systems. (a) Each electric engine order telegraph system must...

2013-10-01

437

A Cochlear Partition Model Incorporating Realistic Electrical and Mechanical Parameters for Outer Hair Cells  

NASA Astrophysics Data System (ADS)

The organ of Corti (OC) is believed to optimize the force transmission from the outer hair cell (OHC) to the basilar membrane and inner hair cell. Recent studies showed that the OC has complex modes of deformation. In an effort to understand the consequence of the OC deformation, we developed a fully deformable 3D finite element model of the OC. It incorporates hair bundle's mechano-transduction and the OHC electrical circuit. Geometric information was taken from the gerbil cochlea at locations with 18 and 0.7 kHz characteristic frequencies. Cochlear partitions of several hundred micrometers long were simulated. The model describes the signature 3D structural arrangement in the OC, especially the tilt of OHC and Deiters cell process. Transduction channel kinetics contributed to the system's mechanics through the hair bundle. The OHC electrical model incorporated the transduction channel conductance, nonlinear capacitance and piezoelectric properties. It also incorporated recent data on the voltage-dependent potassium conductance and membrane time constant. With the model we simulated (1) the limiting frequencies of mechano-transduction and OHC somatic motility and (2) OC transient response to impulse stimuli.

Nam, Jong-Hoon; Fettiplace, Robert

2011-11-01

438

OAK RIDGE NATIONAL LABORATORY SPALLATION NEUTRON SOURCE ELECTRICAL SYSTEMS AVAILABILITY AND IMPROVEMENTS  

SciTech Connect

SNS electrical systems have been operational for 4 years. System availability statistics and improvements are presented for AC electrical systems, DC and pulsed power supplies and klystron modulators.

Cutler, Roy I [ORNL; Peplov, Vladimir V [ORNL; Wezensky, Mark W [ORNL; Norris, Kevin Paul [ORNL; Barnett, William E [ORNL; Hicks, Jim [ORNL; Weaver, Joey T [ORNL; Moss, John [ORNL; Rust, Kenneth R [ORNL; Mize, Jeffery J [ORNL; Anderson, David E [ORNL

2011-01-01

439

A Mobile Care System With Alert Mechanism  

Microsoft Academic Search

Abstract—Hypertension and arrhythmia are chronic diseases, which can be effectively prevented and controlled only if the physi- ological parameters of the patient are constantly monitored, along with the full support of the health education and professional med- ical care. In this paper, a role-based intelligent mobile care system with alert mechanism in chronic care environment is proposed and implemented. The

Ren-guey Lee; Kuei-chien Chen; Chun-chieh Hsiao; Chwan-lu Tseng

2007-01-01

440

Failure mechanisms of thermal barrier systems  

Microsoft Academic Search

Thermal barrier coatings (TBCs) are widely used in turbines for propulsion and power generation. The benefit results from their ability to sustain high thermal gradients in the presence of adequate backside cooling. Lowering the temperature of the metal substrate prolongs the life of the component: whether from environmental attack, creep rupture, or fatigue. Thermal barrier systems exhibit multiple failure mechanisms,

Tao Xu

2005-01-01

441

Interagency mechanical operations group numerical systems group  

SciTech Connect

This report consists of the minutes of the May 20-21, 1971 meeting of the Interagency Mechanical Operations Group (IMOG) Numerical Systems Group. This group looks at issues related to numerical control in the machining industry. Items discussed related to the use of CAD and CAM, EIA standards, data links, and numerical control.

NONE

1997-09-01

442

The Archimedes 2 mechanical assembly planning system  

Microsoft Academic Search

We describe the implementation and performance of Archimedes 2, an integrated mechanical assembly planning system. Archimedes 2 includes two planners, two assembly sequence animation facilities, and an associated robotic workcell. Both planners use fully 3 dimensional data. A rudimentary translator from high level assembly plans to control code for the robotic workcell has also been implemented. We can translate data

S. G. Kaufmann; R. H. Wilson; R. E. Jones; T. L. Calton; A. L. Ames

1996-01-01

443

Survey of electrical submersible systems design, application, and testing  

SciTech Connect

The electrical submersible pump industry has numerous recommended practices and procedures addressing various facets of the operation. Ascertaining the appropriate technique is tedious. Seldom are all the documents available at one location. This synopsis of all the industry practices provides a ready reference for testing, design, and application of electrical submersible pumping systems. An extensive bibliography identifies significant documents for further reference.

Durham, M.O. [Univ. of Tulsa, OK (United States); Lea, J.F. [Amoco EPTG, Tulsa, OK (United States)

1996-05-01

444

Optimization of a photovoltaic system connected to electric power grid  

Microsoft Academic Search

An important aspect related to the photovoltaic system connected to the electric grid is that it can exercise the double function of active power generator and reactive power compensator. Since it is a type of random generation, dependent on environmental conditions, it can supply reactive power to the electrical grid when there is little or no solar radiation. These are

F. L. Albuquerque; A. J. Moraes; G. C. Guimaraes; S. M. R. Sanhueza; A. R. Vaz

2004-01-01

445

Liquefied natural gas-freon electricity generation system  

SciTech Connect

The present invention relates to an electricity generation system, using freon as an agent to circulate between a warm heat source and a cold heat sink, recapturing electrical energy on one side and alleviating thermal pollution in the environment on the other side.

Nozawa, R.

1982-05-25

446

Liquefied natural gas-freon electricity generation system  

SciTech Connect

The present invention relates to an electricity generation system, using freon as an agent to circulate between a warm heat source and a cold heat sink, recapturing electrical energy on one side and alleviating thermal pollution in the environment on the other side.

Nozawa, R.

1983-12-27

447

Modeling and Simulation about an Electric Car's Regenerative Braking System  

Microsoft Academic Search

A kind of regenerative braking system of an electric car is studied in the paper. The car's speed, acceleration, the hydraulic accumulator's pressure and volume are simulated with Matlab while the electric car is braking or accelerating from stop. The hydraulic accumulator can absorb all of the braking energy when braking and the energy stored in the hydraulic accumulator can

Zuowu Ding; Dongbiao Zhao; Jianmin Zuo

2007-01-01

448

Fault Analysis in DC Electric Railways Feeding System  

Microsoft Academic Search

Electric railways and mono-rails in Japan are operated by DC feeding systems. HSCB (high speed circuit breakers) are generally used for these electric installations. Recently, HSVCB (high speed vacuum circuit breakers) have been investigated. HSVCB makes current superimposed on fault current so that the current is forced to be zero and interrupts the current. HSVCB has an advantage such as

R. Ikeda; E. Kaneko

2006-01-01

449

THERMIONIC CONVERSION IN A NUCLEAR-ELECTRIC SPACE PROPULSION SYSTEM  

Microsoft Academic Search

The theory and experimental performance of the thermionic converter is ; analyzed for use in power conversion in a nuclear-electric space propulsion ; system. Electrical propulsion power requirements are shown to demand a minimum ; ratio of powerplant weight to power in the jet. The elements of a powerplant ; into which the converter must be integrated are discussed, including

J. P. Ditz; T. R. Shukay

1961-01-01

450

The Electric Circuit as a System: A New Approach  

Microsoft Academic Search

EnglishIn this new approach to the presentation of the electric circuit, the three fundamental terms current, voltage, and resistance are introduced simultaneously in a qualitative way, using the system aspect of the electric circuit as an integrative base.The starting point to this is the individual knowledge and the conceptional schemes that students bring into the classroom. This approach is in

H. Härtel

1982-01-01

451

Power quality load management for large spacecraft electrical power systems  

NASA Technical Reports Server (NTRS)

In December, 1986, a Center Director's Discretionary Fund (CDDF) proposal was granted to study power system control techniques in large space electrical power systems. Presented are the accomplishments in the area of power system control by power quality load management. In addition, information concerning the distortion problems in a 20 kHz ac power system is presented.

Lollar, Louis F.

1988-01-01

452

Control and measurement of an electro-mechanical system with a phase qubit  

NASA Astrophysics Data System (ADS)

We discuss a hybrid device that merges an electro-mechanical system with a metastable phase qubit. The phase qubit can act as a single photon source and detector, allowing the preparation and readout of a lumped element electrical resonator, whose capacitance is formed by a mechanically compliant vacuum-gap capacitor. Via radiation pressure induced parametric coupling, we can map the quantum state of the 10 GHz electrical resonator on to the long-lived, ˜10 MHz fundamental mode of the mechanical oscillator. This work opens the way toward the preparation of complex phonon states of mechanical motion. We will discuss current progress with this device.

Lecocq, Florent; Teufel, John; Allman, Michael; Cicak, Katarina; da Silva, Fabio; Sirois, Adam; Whittaker, Jed; Aumentado, Joe; Simmonds, Ray

2013-03-01

453

PEGASUS: A multi-megawatt nuclear electric propulsion system  

NASA Technical Reports Server (NTRS)

A propulsion system (PEGASUS) consisting of an electric thruster driven by a multimegawatt nuclear power system is proposed for a manned Mars mission. Magnetoplasmadynamic and mercury-ion thrusters are considered, based on a mission profile containing a 510-day burn time (for a mission time of approximately 1000 days). Both thrusters are capable of meeting the mission parameters. Electric propulsion systems have significant advantages over chemical systems, because of high specific impulse, lower propellant requirements, and lower system mass. The power for the PEGASUS system is supplied by a boiling liquid-metal fast reactor. The power system consists of the reactor, reactor shielding, power conditioning subsystems, and heat rejection subsystems. It is capable of providing a maximum of 8.5 megawatts of electrical power of which 6 megawatts is needed for the thruster system, leaving 1.5 megawatts available for inflight mission applications.

Coomes, Edmund P.; Cuta, Judith M.; Webb, Brent J.; King, David Q.; Patterson, Mike J.; Berkopec, Frank

1986-01-01

454

Ash reduction system using electrically heated particulate matter filter  

DOEpatents

A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.

Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI

2011-08-16

455

Further Study of the Electrical and Mechanical Responses of Slow Fibers in Cat Extraocular Muscles  

PubMed Central

Electrical and mechanical responses have been obtained in situ and in vitro from the superior oblique muscle stimulated by single and repetitive electrical pulses, applied to the trochlear nerve. Two different types of muscle fibers are described, the twitch and the slow. The slow type is characterized electrically by the presence of junctional potentials, which have reversal potentials between -10 and -20 mv, and do not show propagated responses or spikes, during nerve stimulation. When the slow muscle fibers are repetitively stimulated in situ, a prolonged contraction is maintained during stimulation. At the time, the recorded electrical activity is produced locally, at the level of the neuromuscular junctions of the slow fibers. These results indicate that the contractile mechanism of the slow muscle fibers is activated locally and segmentally.

Pilar, G.

1967-01-01

456

The challenges of achieving good electrical and mechanical properties when making structural supercapacitors  

NASA Astrophysics Data System (ADS)

The paper presents results associated with the electro-mechanical characterization of a composite material with power storage capability, identified throughout the paper as a structural supercapacitor. The structural supercapacitor uses electrodes made of carbon fiber weave, a separator made of Celgard 3501, and a solid PEG-based polymer blend electrolyte. To be a viable structural supercapacitor, the material has to have good mechanical and power storage/electrical properties. The literature in this area is inconsistent on which electrical properties are evaluated, and how those properties are assessed. In general, measurements of capacitance or specific capacitance (i.e. capacitance per unit area or per unit volume) are made, without considering other properties such as leakage resistance and equivalent series resistance of the supercapacitor. This paper highlights the significance of these additional electrical properties, discusses the fluctuation of capacitance over time, and proposes methods to improve the stability of the material's electric properties over time.

Ciocanel, C.; Browder, C.; Simpson, C.; Colburn, R.

2013-04-01

457

Analysis of Electric-Submersibles Pumping Systems  

Microsoft Academic Search

This paper presents a field-proven analytical method of evaluating electric-submersible-pumping equipment and well performance jointly. A computerized mathematical model that considers the effects of free gas, pump speed (variable-frequency drives), and pump tapering is described. The method allows accurate calculations of important downhole parameters, including pump intake pressure, pump intake volume (including free gas), pump pressure, and fluid density profile.

K. B. Nolen; S. G. Gibbs

1989-01-01

458

TWRS privatization phase 1 electrical power system  

SciTech Connect

This document includes Conceptual Design Report (CDR) for a new 11 km (7 miles) 230 kV transmission line and a new 40 MVA substation (A6) which will be located east of Grout Facility in 200E Area tank farm. This substation will provide electrical power up to 20 MW each for two private contractor facilities for immobilization and disposal of low activity waste (LAW).

Singh, G.

1997-05-30

459

Solar energy for electric vehicles: systems analysis  

Microsoft Academic Search

Discusses a new tank for carrying solar energy-the zinc-air battery, which can deliver propulsion energy from sunlight with greater efficiency and less value-added expense. This battery generates electric energy by combining zinc from its anode with oxygen from air to form zincate. At the recharging station the zincate is replaced with zinc, and the zincate is sent to a electro-winnowing

H. Oman

1998-01-01

460

Electrical stimuli in the central nervous system microenvironment.  

PubMed

Electrical stimulation to manipulate the central nervous system (CNS) has been applied as early as the 1750s to produce visual sensations of light. Deep brain stimulation (DBS), cochlear implants, visual prosthetics, and functional electrical stimulation (FES) are being applied in the clinic to treat a wide array of neurological diseases, disorders, and injuries. This review describes the history of electrical stimulation of the CNS microenvironment; recent advances in electrical stimulation of the CNS, including DBS to treat essential tremor, Parkinson's disease, and depression; FES for the treatment of spinal cord injuries; and alternative electrical devices to restore vision and hearing via neuroprosthetics (retinal and cochlear implants). It also discusses the role of electrical cues during development and following injury and, importantly, manipulation of these endogenous cues to support regeneration of neural tissue. PMID:25014787

Thompson, Deanna M; Koppes, Abigail N; Hardy, John G; Schmidt, Christine E

2014-07-11

461

Mechanisms of ventricular arrhythmias: a dynamical systems-based perspective  

PubMed Central

Defining the cellular electrophysiological mechanisms for ventricular tachyarrhythmias is difficult, given the wide array of potential mechanisms, ranging from abnormal automaticity to various types of reentry and kk activity. The degree of difficulty is increased further by the fact that any particular mechanism may be influenced by the evolving ionic and anatomic environments associated with many forms of heart disease. Consequently, static measures of a single electrophysiological characteristic are unlikely to be useful in establishing mechanisms. Rather, the dynamics of the electrophysiological triggers and substrates that predispose to arrhythmia development need to be considered. Moreover, the dynamics need to be considered in the context of a system, one that displays certain predictable behaviors, but also one that may contain seemingly stochastic elements. It also is essential to recognize that even the predictable behaviors of this complex nonlinear system are subject to small changes in the state of the system at any given time. Here we briefly review some of the short-, medium-, and long-term alterations of the electrophysiological substrate that accompany myocardial disease and their potential impact on the initiation and maintenance of ventricular arrhythmias. We also provide examples of cases in which small changes in the electrophysiological substrate can result in rather large differences in arrhythmia outcome. These results suggest that an interrogation of cardiac electrical dynamics is required to provide a meaningful assessment of the immediate risk for arrhythmia development and for evaluating the effects of putative antiarrhythmic interventions.

Cherry, Elizabeth M.; Fenton, Flavio H.

2012-01-01

462

High-pressure study of ternary mercury chalcogenides: phase transitions, mechanical and electrical properties  

Microsoft Academic Search

In this paper investigations of electrical and mechanical properties of ternary mercury chalcogenides Hg1-xCdxSe, HgSe1-xSx, HgTe1-xSx were performed subjected to hydrostatic pressure treatment. The influence of cation and anion substitutions was tested on the electrical resistivity dependence of P and microhardness H values before and after applying pressure P up to 2.3 GPa. The variations of both the start pressure

Vladimir V. Shchennikov; Sergey V. Ovsyannikov; Natalya Yu Frolova

2003-01-01

463

Welding time effect on mechanical properties of automotive sheets in electrical resistance spot welding  

Microsoft Academic Search

In this study, the effects of welding time on the tensile-peel strength and tensile-shear strength of welding joints in electrical resistance spot welding of chromate micro-alloyed steel sheets having 1.2mm thicknesses were investigated. A timer and current controlled electrical resistance spot welding machine having 120kVA capacity and a pneumatic application mechanism with a single lever was used to prepare the

S. Aslanlar; A. Ogur; U. Ozsarac; E. Ilhan

2008-01-01

464

Predicting the physico-mechanical properties of rocks from electrical impedance spectroscopy measurements  

Microsoft Academic Search

Electrical resistivity values of eight different samples cored from a fault breccia were measured using an impedance analyser. The uniaxial compressive strength, elastic modulus, point load strength, Schmidt hammer value, P-wave velocity, density and porosity values of the samples were determined in the laboratory. Electrical resistivity values were correlated with the corresponding physico-mechanical properties using the method of least-squares regression

S. Kahraman; M. Alber

2006-01-01

465

ELECTRIC DISCHARGE MILLING AND MECHANICAL GRINDING COMPOUND MACHINING OF SILICON CARBIDE CERAMIC  

Microsoft Academic Search

Silicon carbide (SiC) ceramics have been widely used in modern industry. However, the manufacture of SiC ceramics is not an efficient process. This paper proposes a new technology of machining SiC ceramics with electrical discharge milling and mechanical grinding compound method. The compound process employs the pulse generator used in electrical discharge machining, and uses a water-based emulsion as the

Renjie Ji; Yonghong Liu; Yanzhen Zhang; Baoping Cai; Rong Shen

2010-01-01

466

Design, Modeling, and Test of a System for Atmospheric Electric Field Measurement  

Microsoft Academic Search

In this paper, a new version of the field-mill sensor structure for atmospheric electric field measurements is presented. Both the hardware components (i.e., the mechanical structure, the electronic front end, and the acquisition and control systems) and the data processing software are designed in order to reduce power consumption and enhance the instrument metrological per- formance in terms of accuracy,

Ada Fort; Marco Mugnaini; Valerio Vignoli; Santina Rocchi; Federico Perini; Jader Monari; Marco Schiaffino; Franco Fiocchi

2011-01-01

467

Holographic grating formation mechanism in dye-doped nematic liquid crystal thin layer under dc electric field  

NASA Astrophysics Data System (ADS)

Mechanism of holographic dynamic grating recording in a thin cell with dye doped nematic liquid crystal under laser light has been proposed. Nematic liquid crystal with dye is sandwiched between two coating glass plates covered by ITO conductive and polyimide orientation layers. In this experiment, two interfering laser beams induced spatial modulation of refraction index and form interference pattern in the liquid crystal cell. The recording mechanism is linked with DC electric field driven reorientation of nematic director and induces the bulk photoconductivity of the system.

Parka, Janusz; Januszko, A.; Miniewicz, Andrzej; Zmija, Jozef

2000-05-01

468

Micro electro mechanical system optical switching  

DOEpatents

The present disclosure includes apparatus, system, and method embodiments that provide micro electo mechanical system optical switching and methods of manufacturing switches. For example, one optical switch embodiment includes at least one micro electro mechanical system type pivot mirror structure disposed along a path of an optical signal, the structure having a mirror and an actuator, and the mirror having a pivot axis along a first edge and having a second edge rotatable with respect to the pivot axis, the mirror being capable of and arranged to be actuated to pivot betweeen a position parallel to a plane of an optical signal and a position substantially normal to the plane of the optical signal.

Thorson, Kevin J; Stevens, Rick C; Kryzak, Charles J; Leininger, Brian S; Kornrumpf, William P; Forman, Glenn A; Iannotti, Joseph A; Spahn, Olga B; Cowan, William D; Dagel, Daryl J

2013-12-17

469

Electrically driven cracks in piezoelectric ceramics: experiments and fracture mechanics analysis  

Microsoft Academic Search

Piezoelectric systems like multilayer actuators are susceptible to damage by crack propagation induced by strain incompatibilities. These can arise under electric fields for example between the electroded and external regions. Such incompatibilities have been realised in thin rectangular model specimens from PZT-piezoelectric ceramics with top and bottom electrodes only close to one edge. Under an electric field, controlled crack propagation

H.-A. Bahr; V.-B. Pham; D. C. Lupascu; H. Balke; J. Rödel; U. Bahr

2002-01-01

470

The effect of electric charge on the mechanical properties of graphene  

NASA Astrophysics Data System (ADS)

The effect of electric charge on the mechanical properties of graphene under tensile loading is investigated by using molecular dynamics method. A modified atomistic moment method based on the classical electrostatics theory is proposed to obtain the distribution of extra charges induced by an external electric field and net electric charges stored in graphene. The electrostatic interactions between charged atoms are calculated using the coulomb law. The results show that the Young's modulus and the critical fracture stress under uniaxial tension decrease with the increase of electric potential and net charges on graphene. The failure of graphene induced by electric charges is found to be controlled by charge level. The results indicate that the carbon-carbon bonds at the edge of graphene will break first.

Hao, Peng; Gao, YuanWen; Zhou, YouHe

2013-06-01

471

Precise time and time interval applications to electric power systems  

NASA Technical Reports Server (NTRS)

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on measuring power system frequency consistently in many locations. The internal oscillators in the widely dispersed frequency measuring units must be syntonized. Elaborate protection and control systems guard the high voltage equipment from short and open circuits. For the highest reliability of electric service, engineers need to study all control system operations. Precise timekeeping networks aid in the analysis of power system operations by synchronizing the clocks on recording instruments. Utility engineers want to reproduce events that caused loss of service to customers. Precise timekeeping networks can synchronize protective relay test-sets. For dependable electrical service, all generators and large motors must remain close to speed synchronism. The stable response of a power system to perturbations is critical to continuity of electrical service. Research shows that measurement of the power system state vector can aid in the monitoring and control of system stability. If power system operators know that a lightning storm is approaching a critical transmission line or transformer, they can modify operating strategies. Knowledge of the location of a short circuit fault can speed the re-energizing of a transmission line. One fault location technique requires clocks synchronized to one microsecond. Current research seeks to find out if one microsecond timekeeping can aid and improve power system control and operation.

Wilson, Robert E.

1992-01-01

472

Precise time and time interval applications to electric power systems  

NASA Astrophysics Data System (ADS)

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on measuring power system frequency consistently in many locations. The internal oscillators in the widely dispersed frequency measuring units must be syntonized. Elaborate protection and control systems guard the high voltage equipment from short and open circuits. For the highest reliability of electric service, engineers need to study all control system operations. Precise timekeeping networks aid in the analysis of power system operations by synchronizing the clocks on recording instruments. Utility engineers want to reproduce events that caused loss of service to customers. Precise timekeeping networks can synchronize protective relay test-sets. For dependable electrical service, all generators and large motors must remain close to speed synchronism. The stable response of a power system to perturbations is critical to continuity of electrical service. Research shows that measurement of the power system state vector can aid in the monitoring and control of system stability. If power system operators know that a lightning storm is approaching a critical transmission line or transformer, they can modify operating strategies. Knowledge of the location of a short circuit fault can speed the re-energizing of a transmission line. One fault location technique requires clocks synchronized to one microsecond. Current research seeks to find out if one microsecond timekeeping can aid and improve power system control and operation.

Wilson, Robert E.

1992-07-01

473

Tissue heterogeneity as a mechanism for localized neural stimulation by applied electric fields  

NASA Astrophysics Data System (ADS)

We investigate the heterogeneity of electrical conductivity as a new mechanism to stimulate excitable tissues via applied electric fields. In particular, we show that stimulation of axons crossing internal boundaries can occur at boundaries where the electric conductivity of the volume conductor changes abruptly. The effectiveness of this and other stimulation mechanisms was compared by means of models and computer simulations in the context of transcranial magnetic stimulation. While, for a given stimulation intensity, the largest membrane depolarization occurred where an axon terminates or bends sharply in a high electric field region, a slightly smaller membrane depolarization, still sufficient to generate action potentials, also occurred at an internal boundary where the conductivity jumped from 0.143 S m-1 to 0.333 S m-1, simulating a white-matter-grey-matter interface. Tissue heterogeneity can also give rise to local electric field gradients that are considerably stronger and more focal than those impressed by the stimulation coil and that can affect the membrane potential, albeit to a lesser extent than the two mechanisms mentioned above. Tissue heterogeneity may play an important role in electric and magnetic 'far-field' stimulation.

Miranda, P. C.; Correia, L.; Salvador, R.; Basser, P. J.

2007-09-01

474

Statistical mechanics of a discrete nonlinear system  

PubMed

Statistical mechanics of the discrete nonlinear Schrodinger equation is studied by means of analytical and numerical techniques. The lower bound of the Hamiltonian permits the construction of standard Gibbsian equilibrium measures for positive temperatures. Beyond the line of T = infinity, we identify a phase transition through a discontinuity in the partition function. The phase transition is demonstrated to manifest itself in the creation of breatherlike localized excitations. Interrelation between the statistical mechanics and the nonlinear dynamics of the system is explored numerically in both regimes. PMID:11019194

Rasmussen; Cretegny; Kevrekidis; Gronbech-Jensen

2000-04-24

475

Statistical mechanics of a discrete nonlinear system  

SciTech Connect

Statistical mechanics of the discrete nonlinear Schroedinger equation is studied by means of analytical and numerical techniques. The lower bound of the Hamiltonian permits the construction of standard Gibbsian equilibrium measures for positive temperatures. Beyond the line of T=infinity, we identify a phase transition, through a discontinuity in the partition function. The phase transition is demonstrated to manifest itself in the creation of breather-like localized excitations. Interrelation between the statistical mechanics and the nonlinear dynamics of the system is explored numerically in both regimes.

Rasmussen, K.O.; Cretegny, T.; Kevrekidis, P.G.; Gronbech-Jensen, Niels

1999-09-01

476

Statistical Mechanics of a Discrete Nonlinear System  

SciTech Connect

Statistical mechanics of the discrete nonlinear Schroedinger equation is studied by means of analytical and numerical techniques. The lower bound of the Hamiltonian permits the construction of standard Gibbsian equilibrium measures for positive temperatures. Beyond the line of T={infinity} , we identify a phase transition through a discontinuity in the partition function. The phase transition is demonstrated to manifest itself in the creation of breatherlike localized excitations. Interrelation between the statistical mechanics and the nonlinear dynamics of the system is explored numerically in both regimes. (c) 2000 The American Physical Society.

Rasmussen, K. Oe.; Cretegny, T.; Kevrekidis, P. G.; Groenbech-Jensen, Niels

2000-04-24

477

12. LOCK, ELECTRICAL SYSTEM, LOCK, DAM, AND NAVIGATION LIGHTING UNITS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. LOCK, ELECTRICAL SYSTEM, LOCK, DAM, AND NAVIGATION LIGHTING UNITS (October 1935) - Mississippi River 9-Foot Channel Project, Lock & Dam No. 18, Upper Mississippi River, Gladstone, Henderson County, IL

478

76. LOCK, ELECTRICAL SYSTEM, LOCK, DAM AND NAVIGATION LIGHTING UNITS. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

76. LOCK, ELECTRICAL SYSTEM, LOCK, DAM AND NAVIGATION LIGHTING UNITS. February 1938 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

479

Industry Sector Analysis, Mexico: Electric Power Generating Systems and Equipment.  

National Technical Information Service (NTIS)

The market survey covers the electric power generating systems and equipment market in Mexico. The analysis contains statistical and narrative information on projected market demand, end-users; receptivity of Mexican consumers to U.S. products; the compet...

O. Gonzales A. Gayou

1992-01-01