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1

MPPT Battery Charger for Stand-Alone Wind Power System  

Microsoft Academic Search

In this paper, a buck-type power converter as the bat- tery charger for the stand-alone wind power system is proposed. The proposed power converter can harvest the maximum power from the wind turbine while generating pulsating current for the battery bank to improve the charging efficiency. The maximum power point tracking function is realized by the constant on-time control, the

Kuo-Yuan Lo; Yaow-Ming Chen; Yung-Ruei Chang

2011-01-01

2

Power quality improvement of a stand-alone power system subjected to various disturbances  

Microsoft Academic Search

In wind-diesel stand-alone power systems, the disturbances like random nature of wind power, turbulent wind, sudden changes in load demand and the wind park disconnection effect continuously the system voltage and frequency. The satisfactory operation of such a system is not an easy task and the control design has to take in to account all these subtleties. For maintaining the

Shameem Ahmad Lone; Mairaj Ud-Din Mufti

2006-01-01

3

Stand-alone, FCG-driven High Power Microwave system  

Microsoft Academic Search

An explosively driven High Power Microwave (HPM) source has been developed that is based on the use of a Flux Compression Generator (FCG) as the primary driver. Four main components comprise the HPM system, and include a capacitor-based seed energy source, a dual-staged FCG, a power conditioning unit and an HPM diode (reflex-triode vircator). Volume constraints dictate that the entire

A. Young; A. Neuber; M. Elsayed; J. Walter; J. Dickens; M. Kristiansen; L. L. Altgilbers

2009-01-01

4

Power Management of a Stand-Alone Wind\\/Photovoltaic\\/Fuel Cell Energy System  

Microsoft Academic Search

This paper proposes an AC-linked hybrid wind\\/photovoltaic (PV)\\/fuel cell (FC) alternative energy system for stand-alone applications. Wind and PV are the primary power sources of the system, and an FC-electrolyzer combination is used as a backup and a long-term storage system. An overall power management strategy is designed for the proposed system to manage power flows among the different energy

Caisheng Wang; M. Hashem Nehrir

2008-01-01

5

Power management of a stand-alone wind\\/photovoltaic\\/fuel-cell energy system  

Microsoft Academic Search

Summary form only given. This paper proposes an ac-linked hybrid wind\\/photovoltaic (PV)\\/fuel-cell (FC) alternative energy system for stand-alone applications. Wind and PV are the primary power sources of the system, and a FC-electrolyzer combination is used as a backup and long term storage system. An overall power management strategy is designed for the proposed system to manage power flows among

Caisheng Wang; H. Nehrir

2008-01-01

6

Novel Power Control Scheme for Stand-Alone Photovoltaic Generation System  

Microsoft Academic Search

This study mainly develops a novel power control scheme for a stand-alone photovoltaic (PV) generation system. In order to make the PV generation system more flexibility and expandability, the later power circuit is composed of a high step-up converter and a pulse-width-modulation (PWM) inverter. In the DC-DC power conversion, the high step-up converter is introduced to improve the conversion efficiency

Rong-Jong Wai; Chung-You Lin; Wen-Hung Wang

2006-01-01

7

Comparative evaluation of reactive power compensation methods for a stand-alone wind energy conversion system  

Microsoft Academic Search

This paper provides a comparative performance evaluation of four different reactive power compensation approaches for a stand-alone wind energy conversion system (WECS), composed of a wind turbine and a squirrel-cage induction generator (SCIG), and feeding a constant balanced 3-phase inductive load. The reactive power compensation schemes investigated are: fixed-capacitor bank, switched-capacitor bank, static Var compensator (SVC), and static synchronous compensator

M. Elnashar; M. Kazerani; R. El Shatshat; M. M. A. Salama

2008-01-01

8

Why are remote Western Australians installing renewable energy technologies in stand-alone power supply systems?  

Microsoft Academic Search

As people living in remote areas rely on SPS systems for their electricity and water needs, they hold a practical and non-idealistic perspective towards using renewable energy technologies. This research explores pastoral owner-operators’ personal experience and opinion of stand-alone power supply (SPS) systems over 30years in remote pastoral regions Western Australia (WA). This research was undertaken qualitatively in terms of

Mark P. McHenry

2009-01-01

9

Estimating loss-of-power probabilities of stand-alone photovoltaic solar energy systems  

Microsoft Academic Search

This paper describes an approximate approach to evaluating the performance, including the probability of loss-of-power (or loss-of-load, as some would have it) of stand-alone photovoltaic solar energy systems. The method treats the energy capture, storage and disbursement process as a random walk in the storage domain. To apply the technique, one must know the variance, as well as the mean,

L. L. Bucciarelli Jr.

1984-01-01

10

Hybrid Configuration of Darrieus and Savonius Rotors for Stand-alone Power Systems  

NASA Astrophysics Data System (ADS)

The suitable hybrid configuration of Darrieus lift-type and Savonius drag-type rotors for stand-alone wind turbine-generator systems is discussed using our dynamic simulation model. Two types of hybrid configurations are taken up: Type-A installs the Savonius rotor inside the Darrieus rotor and Type-B installs the Savonius rotor outside the Darrieus rotor. The computed results of the output characteristics and the dynamic behaviors of the system operated at the maximum power coefficient points show that Type-A, which has fine operating behavior to wind speed changes and can be compactly designed because of a shorter rotational shaft, is an effective way for self-controlled stand-alone small-scale systems.

Wakui, Tetsuya; Tanzawa, Yoshiaki; Hashizume, Takumi; Nagao, Toshio

11

Development of a microprocessor controller for stand-alone photovoltaic power systems  

NASA Technical Reports Server (NTRS)

A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

Millner, A. R.; Kaufman, D. L.

1984-01-01

12

International market assessment of stand-alone photovoltaic power systems for cottage industry applications  

NASA Technical Reports Server (NTRS)

The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

Philippi, T. M.

1981-01-01

13

Automation infrastructure and operation control strategy in a stand-alone power system based on renewable energy sources  

Microsoft Academic Search

The design of the automation system and the implemented operation control strategy in a stand-alone power system in Greece are fully analyzed in the present study. A photovoltaic array and three wind generators serve as the system main power sources and meet a predefined load demand. A lead-acid accumulator is used to compensate the inherent power fluctuations (excess or shortage)

Chrysovalantou Ziogou; Dimitris Ipsakis; Costas Elmasides; Fotis Stergiopoulos; Simira Papadopoulou; Panos Seferlis; Spyros Voutetakis

2011-01-01

14

Stand-alone flat-plate photovoltaic power systems: System sizing and life-cycle costing methodology for Federal agencies  

NASA Technical Reports Server (NTRS)

A simple methodology to estimate photovoltaic system size and life-cycle costs in stand-alone applications is presented. It is designed to assist engineers at Government agencies in determining the feasibility of using small stand-alone photovoltaic systems to supply ac or dc power to the load. Photovoltaic system design considerations are presented as well as the equations for sizing the flat-plate array and the battery storage to meet the required load. Cost effectiveness of a candidate photovoltaic system is based on comparison with the life-cycle cost of alternative systems. Examples of alternative systems addressed are batteries, diesel generators, the utility grid, and other renewable energy systems.

Borden, C. S.; Volkmer, K.; Cochrane, E. H.; Lawson, A. C.

1984-01-01

15

Current status of research on optimum sizing of stand-alone hybrid solar–wind power generation systems  

Microsoft Academic Search

Solar and wind energy systems are omnipresent, freely available, environmental friendly, and they are considered as promising power generating sources due to their availability and topological advantages for local power generations. Hybrid solar–wind energy systems, uses two renewable energy sources, allow improving the system efficiency and power reliability and reduce the energy storage requirements for stand-alone applications. The hybrid solar–wind

Wei Zhou; Chengzhi Lou; Zhongshi Li; Lin Lu; Hongxing Yang

2010-01-01

16

Power fluctuations suppression of stand-alone hybrid generation combining solar photovoltaic\\/wind turbine and fuel cell systems  

Microsoft Academic Search

In this paper a hybrid energy system combining variable speed wind turbine, solar photovoltaic and fuel cell generation systems is presented to supply continuous power to residential power applications as stand-alone loads. The wind and photovoltaic systems are used as main energy sources while the fuel cell is used as secondary or back-up energy source. Three individual dc–dc boost converters

Nabil A. Ahmed; Masafumi Miyatake; A. K. Al-Othman

2008-01-01

17

Optimization of a stand-alone Solar PV-Wind-DG Hybrid System for Distributed Power Generation at Sagar Island  

NASA Astrophysics Data System (ADS)

An estimation of a stand-alone solar PV and wind hybrid system for distributed power generation has been made based on the resources available at Sagar island, a remote area distant to grid operation. Optimization and sensitivity analysis has been made to evaluate the feasibility and size of the power generation unit. A comparison of the different modes of hybrid system has been studied. It has been estimated that Solar PV-Wind-DG hybrid system provides lesser per unit electricity cost. Capital investment is observed to be lesser when the system run with Wind-DG compared to Solar PV-DG.

Roy, P. C.; Majumder, A.; Chakraborty, N.

2010-10-01

18

Control aspects of the Schuchuli Village stand-alone photovoltaic power system  

NASA Technical Reports Server (NTRS)

A photovoltaic power system in an Arizona Indian village was installed. The control subsystem of this photovoltaic power system was analyzed. The four major functions of the control subsystem are: (1) voltage regulation; (2) load management; (3) water pump control; and (4) system protection. The control subsystem functions flowcharts for the control subsystem operation, and a computer program that models the control subsystem are presented.

Groumpos, P. P.; Culler, J. E.; Delombard, R.

1984-01-01

19

Analysis of a stand-alone power system for remote-site applications. Final report  

SciTech Connect

The Coast Guard has over 40 automated remote lighthouses which are powered by a continuously run, diesel-electric generator. Continuous operation of a diesel generator increases maintenance requirements as well as fuel costs. Previous studies have indicated that maintenance and operational costs at remote, automated lighthouses could be substantially reduced by incorporating a hybrid-energy-management system. Such a 120-volt system was designed, developed, and built and includes the following major components: diesel-electric generator, wind turbine generator, battery storage, inverter, system controller and lighthouse load. This report discusses the system design, the chronological record of events, conclusions, and recommendations of over three months of continuous data collection and system operation. Additionally, each major system component is discussed in detail in an appropriate appendix.

Thacker, J.R.

1986-05-01

20

Development of a microprocessor controller for stand-alone photovoltaic power systems  

SciTech Connect

As the cost of photovoltaic modules decreases, system control and related engineering costs become very important. To meet this need for flexibility with a minimum of customizing cost, and yet consume only a few watts of power is within the capabilities of today's microprocessor. The first unit was produced under DOE contract DEN3-310 and tested for NASA at TriSolarCorp. It is 5kW maximum power controlling battery charger which can also be configured as a 5kW batteryless motor drive. The entire controller interfaces with existing 500 watt MPC power modules, operates in a NEMA-4 enclosuer over an ambient temperature range of -25/sup 0/C to /sup +/45/sup 0/C, operates from either a 12V battery or a 40V to 300V dc unregulated solar array or battery bus. The unit design and cost are discussed, and testing is reported.

Millner, A.R.; Kaufman, D.L.

1984-06-01

21

Optimal sizing of battery storage for stand-alone hybrid (photo-voltaic + diesel) power systems  

NASA Astrophysics Data System (ADS)

An important element of hybrid photo- voltaic(PV) + diesel sytem is battery storage. Size of battery storage plays a role in optimum operation of the hybrid system. Emphasis needs to be placed on this issue. In this perspective, hourly solar radiation data, for the period 1986 93 recorded at Dhahran, Saudi Arabia, have been analyzed to investigate the optimum size of battery storage capacity for hybrid (PV + diesel) power systems. Various sizing configurations have been simulated. The monthly average daily values of solar global radiation range from 3.61 to 7.96kWh/m2. As a case study, hybrid systems considered in the present analysis consist of 225m2 PV array area (panels/modules) supplemented with battery storage unit and diesel backup generators (to meet the load requirements of a typical residential building with annual electrical energy demand of 35,200kWh). The monthly average energy generated from the aforementioned hybrid system for different scenarios has been presented. More importantly, the study explores the influence of variation of battery storage capacity on hybrid power generation. The results exhibit a trade-off between size of the storage capacity and diesel power to be generated to cope with annual load distribution. Concurrently, the energy to be generated from the diesel generator and the number of operational hours of the diesel system to meet the load demand have been also addressed.The study shows that for optimum operation of diesel system, storage capacity equivalent to 12 18h of maximum monthly average hourly demand need to be used. It has been found that in the absence of battery bank, ˜58% of the load needs to be provided by the diesel system. However, use of 12h of battery storage (autonomy) reduces diesel energy generation by ˜49% and the number of hours of operation of the diesel system get reduced by about ˜82%. The findings of this study can be employed as a tool for sizing of battery storage for PV/diesel systems for other regions having climates similar to the location considered in the study.

Shaahid, S. M.; Elhadidy, M. A.

2005-09-01

22

Unit sizing of stand-alone hybrid wind\\/PV\\/fuel cell power generation systems  

Microsoft Academic Search

An economic evaluation of a hybrid wind\\/photovoltaic\\/fuel cell generation system for a typical home in the Pacific Northwest is performed. In this configuration the combination of a fuel cell stack, an electrolyzer, and a hydrogen storage tank is used for the energy storage system. This system is compared to a traditional hybrid energy system with battery storage. A computer program

D. B. Nelson; M. H. Nehrir; C. Wang

2005-01-01

23

Power system analysis project Modeling and Sizing optimization of Stand-alone  

E-print Network

the solar radiation of the inclined solar panels. All these data act as the input of the mathematical model of solar panels and wind turbine to simulate the system. The minimization of the objective cost function. The most popular integration of renewable energy is through wind turbine and solar panels. Figure 2 shows

Lavaei, Javad

24

High-Performance Stand-Alone Photovoltaic Generation System  

Microsoft Academic Search

This study develops a high-performance stand-alone photovoltaic (PV) generation system. To make the PV generation system more flexible and expandable, the backstage power circuit is composed of a high step-up converter and a pulsewidth-modulation (PWM) inverter. In the dc-dc power conversion, the high step-up converter is introduced to improve the conversion efficiency in conventional boost converters to allow the parallel

Rong-Jong Wai; Wen-Hung Wang; Chung-You Lin

2008-01-01

25

Design and simulation of a stand-alone wind-diesel generator with a flywheel energy storage system to supply the required active and reactive power  

Microsoft Academic Search

This paper presents the design and simulation of a stand-alone generation plant, which combines a wind-diesel generator with a flywheel energy storage unit. Without any storage system, the diesel engine has to be continuously operating, resulting in high fuel consumption. The flywheel is designed to supply the rated power during 1.8 minutes. This time is enough to compensate regular wind

I. J. Iglesias; L. Garcia-Tabares; A. Agudo; I. Cruz; L. Arribas

2000-01-01

26

Modular photovoltaic stand-alone systems: Phase 1  

NASA Technical Reports Server (NTRS)

A family of modular stand-alone power systems that covered the range in power level from 1 kw to 14 kw was developed. Products within this family were required to be easily adaptable to different environments and applications, and were to be both reliable and cost effective. Additionally, true commonality in hardware was to be exploited, and unnecessary recurrence of design and development costs were to be minimized; thus improving hardware availability. Assurance of compatibility with large production runs, was also an underlying program goal. A secondary objective was to compile, evaluate, and determine the economic and technical status of available, and potentially available, technology options associated with the balance of systems (BOS) for stand-along photovoltaic (PV) power systems. The secondary objective not only directly supported the primary but additionally contributed to the definition and implementation of the BOS cost reduction plan.

Naff, G. J.; Marshall, N. A.

1983-01-01

27

Power control and modeling of a solar-ultra capacitor hybrid energy system for stand-alone applications  

Microsoft Academic Search

This paper proposes the integration of photovoltaic (PV) and energy storage systems for sustained power generation. In this proposed system, whenever the PV system cannot completely meet load demands, the super capacitor provides power to meet the remaining load. A power management strategy is designed for the proposed system to manage power flows between PV systems and ultracapacitor(UC). The main

Jae Hoon Cho; Won-Pyo Hong

2010-01-01

28

The Loss of Power Supply Probability as a Technique for Designing Stand-Alone Solar Electrical (Photovoltaic) Systems  

Microsoft Academic Search

It is noted that most of the analysis and design methods used in solar electrical systems (SESs) are based on the concept of power supply during a number of autonomous days (NAD). The NAD value is the number of consecutive days on which no power is supplied to the system from the solar cell array (SCA). The storage system capacity

E. Ofry; A. Braunstein

1983-01-01

29

Hybrid stand-alone renewable energy system with high fuel-cell efficiency and unity power factor  

Microsoft Academic Search

The paper presents a hybrid standalone power conversion strategy for the integrated connection of multiple remote loads. The proposed system consists of fuel cells, PV panels, a wind turbine and batteries. The primary aims of the proposed controller are to operate the fuel cells about their maximum possible efficiency whilst maintaining unity power factor. A control technique for charging and

E. K. Hussain; C. M Bingham; D. Stone

2011-01-01

30

Photovoltaic stand-alone modular systems, phase 2  

NASA Technical Reports Server (NTRS)

The final hardware and system qualification phase of a two part stand-alone photovoltaic (PV) system development is covered. The final design incorporated modular, power blocks capable of expanding incrementally from 320 watts to twenty kilowatts (PK). The basic power unit (PU) was nominally rated 1.28 kWp. The controls units, power collection buses and main lugs, electrical protection subsystems, power switching, and load management circuits are housed in a common control enclosure. Photo-voltaic modules are electrically connected in a horizontal daisy-chain method via Amp Solarlok plugs mating with compatible connectors installed on the back side of each photovoltaic module. A pair of channel rails accommodate the mounting of the modules into a frameless panel support structure. Foundations are of a unique planter (tub-like) configuration to allow for world-wide deployment without restriction as to types of soil. One battery string capable of supplying approximately 240 ampere hours nominal of carryover power is specified for each basic power unit. Load prioritization and shedding circuits are included to protect critical loads and selectively shed and defer lower priority or noncritical power demands. The baseline system, operating at approximately 2 1/2 PUs (3.2 kW pk.) was installed and deployed. Qualification was successfully complete in March 1983; since that time, the demonstration system has logged approximately 3000 hours of continuous operation under load without major incident.

Naff, G. J.; Marshall, N. A.

1983-01-01

31

Stand-alone PEM water electrolysis system for fail safe operation with a renewable energy source  

Microsoft Academic Search

A complete stand-alone electrolyser system has been constructed as a transportable unit for demonstration of a sustainable energy facility based on hydrogen and a renewable energy source. The stand-alone unit is designed to support a polymer electrolyte membrane (PEM) stack operating at up to ?4kW input power with a stack efficiency of about 80% based on HHV of hydrogen. It

R. E. Clarke; S. Giddey; S. P. S. Badwal

2010-01-01

32

Unit sizing and cost analysis of stand-alone hybrid wind\\/PV\\/fuel cell power generation systems  

Microsoft Academic Search

An economic evaluation of a hybrid wind\\/photovoltaic\\/fuel cell (FC) generation system for a typical home in the Pacific Northwest is performed. In this configuration the combination of a FC stack, an electrolyser, and hydrogen storage tanks is used as the energy storage system. This system is compared to a traditional hybrid energy system with battery storage. A computer program has

D. B. Nelson; M. H. Nehrir; C. Wang

2006-01-01

33

Study of a thermoelectric system equipped with a maximum power point tracker for stand-alone electric generation.  

NASA Astrophysics Data System (ADS)

According to the International Energy Agency, 1.4 billion people are without electricity in the poorest countries and 2.5 billion people rely on biomass to meet their energy needs for cooking in developing countries. The use of cooking stoves equipped with small thermoelectric generator to provide electricity for basic needs (LED, cell phone and radio charging device) is probably a solution for houses far from the power grid. The cost of connecting every house with a landline is a lot higher than dropping thermoelectric generator in each house. Thermoelectric generators have very low efficiency but for isolated houses, they might become really competitive. Our laboratory works in collaboration with plane`te-bois (a non governmental organization) which has developed energy-efficient multifunction (cooking and hot water) stoves based on traditional stoves designs. A prototype of a thermoelectric generator (Bismuth Telluride) has been designed to convert a small part of the energy heating the sanitary water into electricity. This generator can produce up to 10 watts on an adapted load. Storing this energy in a battery is necessary as the cooking stove only works a few hours each day. As the working point of the stove varies a lot during the use it is also necessary to regulate the electrical power. An electric DC DC converter has been developed with a maximum power point tracker (MPPT) in order to have a good efficiency of the electronic part of the thermoelectric generator. The theoretical efficiency of the MMPT converter is discussed. First results obtained with a hot gas generator simulating the exhaust of the combustion chamber of a cooking stove are presented in the paper.

Favarel, C.; Champier, D.; Bédécarrats, J. P.; Kousksou, T.; Strub, F.

2012-06-01

34

US manufacturers of commercially available stand-alone photovoltaic lighting systems  

SciTech Connect

This report introduces photovoltaic (PV) lighting systems, gives some specifications for ordering these systems, and provides a list of some of the manufacturers of these systems in the United States. These PV lighting systems are all commercially available. They are stand-alone systems because they are not tied to the electric utility power grid.

McNutt, P.

1994-05-01

35

Performance of a stand-alone renewable energy system based on energy storage as hydrogen  

Microsoft Academic Search

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energy (RE). A stand-alone RE system based on energy storage as hydrogen has been developed and installed at the Hydrogen Research Institute, and successfully tested for autonomous operation with developed control system and power conditioning devices. The excess energy produced, with respect to the load requirement, has been

Kodjo Agbossou; Mohanlal Kolhe; Jean Hamelin; Tapan K. Bose

2004-01-01

36

Pre-feasibility study of stand-alone hybrid energy systems for applications in Newfoundland  

Microsoft Academic Search

A potential solution for stand-alone power generation is to use a hybrid energy system in parallel with some hydrogen energy storage. In this paper, a pre-feasibility study of using hybrid energy systems with hydrogen as an energy carrier for applications in Newfoundland, Canada is explained. Various renewable and non-renewable energy sources, energy storage methods and their applicability in terms of

M. J. Khan; M. T. Iqbal

2005-01-01

37

System design optimization for stand-alone photovoltaic systems sizing by using superstructure model  

NASA Astrophysics Data System (ADS)

Although the photovoltaic (PV) systems have been increasingly installed as an alternative and renewable green power generation, the initial set up cost, maintenance cost and equipment mismatch are some of the key issues that slows down the installation in small household. This paper presents the design optimization of stand-alone photovoltaic systems using superstructure model where all possible types of technology of the equipment are captured and life cycle cost analysis is formulated as a mixed integer programming (MIP). A model for investment planning of power generation and long-term decision model are developed in order to help the system engineer to build a cost effective system.

Azau, M. A. M.; Jaafar, S.; Samsudin, K.

2013-06-01

38

Optimisation of a Small Non Controlled Wind Energy Conversion System for Stand-Alone Applications  

E-print Network

Optimisation of a Small Non Controlled Wind Energy Conversion System for Stand-Alone Applications. This article proposes a method to optimize the design of a small fixed-voltage wind energy conversion system are shown and discussed. Key words Wind energy conversion system, stand-alone application, nonlinear

Paris-Sud XI, Université de

39

Stand-alone photovoltaic (PV) powered electrochromic window  

DOEpatents

A variable transmittance double pane window includes an electrochromic material that has been deposited on one pane of the window in conjunction with an array of photovoltaic cells deposited along an edge of the pane to produce the required electric power necessary to vary the effective transmittance of the window. A battery is placed in a parallel fashion to the array of photovoltaic cells to allow the user the ability to manually override the system when a desired transmittance is desired. 11 figures.

Benson, D.K.; Crandall, R.S.; Deb, S.K.; Stone, J.L.

1995-01-24

40

Stand-alone photovoltaic (PV) powered electrochromic window  

DOEpatents

A variable transmittance double pane window includes an electrochromic material that has been deposited on one pane of the window in conjunction with an array of photovoltaic cells deposited along an edge of the pane to produce the required electric power necessary to vary the effective transmittance of the window. A battery is placed in a parallel fashion to the array of photovoltaic cells to allow the user the ability to manually override the system when a desired transmittance is desired.

Benson, David K. (Golden, CO); Crandall, Richard S. (Boulder, CO); Deb, Satyendra K. (Boulder, CO); Stone, Jack L. (Lakewood, CO)

1995-01-01

41

Decoupled state estimator design for stand-alone photovoltaic system  

Microsoft Academic Search

This paper describes decoupled state estimator design technique for stand-atone photovoltaic system. The main components of the systems are solar array, power converter and battery. The lithium batteries are widely used in the mobile and hybrid power traction system. The converter requires solar cell voltage and current, battery voltage and current for controlling solar cell and battery status. Due to

il-Song Kim; Pyeong-Sick Ji; Un-Dong Han; Chin-Gook Lhee; Hong-Gyu Kim

2009-01-01

42

Life cycle cost analysis of a stand-alone PV system in rural Kenya  

NASA Astrophysics Data System (ADS)

The purpose of this quantitative research study was to determine the economic feasibility of a stand-alone PV system to electrify a rural area in Kenya. The research conducted involved a comprehensive review of all the relevant literature associated with the study. Methodologies were extrapolated from this extensive literature to develop a model for the complete design and economic analysis of a stand-alone PV system. A women's center in rural Kenya was used as a worked example to demonstrate the workings of the model. The results suggest that electrifying the center using a stand-alone PV system is an economically viable option which is encouraging for the surrounding area. This model can be used as a business model to determine the economic feasibility of a stand-alone PV system in alternative sites in Kenya.

Daly, Emma

43

Photovoltaic stand-alone systems: Preliminary engineering design handbook  

NASA Astrophysics Data System (ADS)

Component design and engineering information, including estimation and reduction strategies, FV array characteristics, and material on batteries, power handling equipment, and back up systems are presented. The data needed to begin the design process and preliminary system design considerations are discussed. These considerations include analysis of insolation and siting, system sizing, feasibility assessment and reliability engineering approaches. Information on system design procedures and applicable codes and standards is presented. Information on system installation, operation, maintenance issues, personnel and facility safety requirements and various means of calculating insolation, including computer software and statistical computations are emphasized.

Macomber, H. L.; Ruzek, J. B.; Costello, F. A.

1981-08-01

44

4-E (energy–exergy–environmental–economic) analyses of line-focusing stand-alone concentrating solar power plants  

Microsoft Academic Search

In this study, energy–exergy–environmental–economic (4-E) analyses of stand-alone line-focusing concentrating solar power plants are carried out for different plant capacities ranging from 1 to 50 MWe<\\/sub>. Solar power plants based on concentrating power technologies are used to harness the solar radiation effectively. Among the solar power technologies, line-focusing concentrating systems such as linear Fresnel reflector (LFR) and parabolic trough collector

K. Ravi Kumar; K. S. Reddy

2012-01-01

45

Ris-R-1219(EN) / SEC-R-12 Models for a Stand-Alone PV System  

E-print Network

Risø-R-1219(EN) / SEC-R-12 Models for a Stand-Alone PV System Anca D. Hansen, Poul Sørensen, Lars H presents a number of models for modelling and simulation of a stand-alone photovoltaic (PV) system mathematical models for each individual element of a stand-alone PV system, namely solar cells, battery

46

Integration of a stand-alone expert system with a hospital information system.  

PubMed Central

A stand-alone PC expert system for evaluating the appropriateness of inpatient admissions has been integrated with an existing hospital information system. The expert system supports preadmission screening for appropriateness of inpatient admissions. The HIS provides extensive clinical data in a coded electronic form, permitting high-level decision support. The integrated system was developed for a 20 week randomized clinical trial to evaluate the effects of preadmission screening on inappropriate inpatient admissions. Three factors of the integration are considered: programmatic integration of the expert system, seamless presentation of mixed platform applications, and integration of coded data from the stand-alone application into the HIS data structure. PMID:1482911

Hales, J. W.; Gardner, R. M.; Huff, S. M.

1992-01-01

47

Hydrogen as an energy carrier in stand-alone applications based on PV and PV–micro-hydro systems  

Microsoft Academic Search

The paper compares two different models of a hypothetical stand-alone energy system based only on renewable sources (solar irradiance and micro-hydro power) integrated with a system for the production of hydrogen (electrolyzer, compressed gas storage and proton exchange membrane fuel cell or PEMFC). The models of both systems have been designed to supply the electricity needs of a residential user

M. Santarelli; S. Macagno

2004-01-01

48

Analysis of merits of hybrid wind/photovoltaic concept for stand-alone systems  

NASA Astrophysics Data System (ADS)

Methods for evaluating the merits of hybrid wind/photovoltaic systems for use in stand-alone applications were developed. The optimum mix of wind and photovoltaic power with an electrochemical storage system, with or without fossil fuel generator backup, depends upon the individual subsystem economics. A computer code was developed to calculate the optimum subsystem sizes that minimize the levelized energy cost. The actual merits of a hybrid system over a pure photovoltaic or wind system depend upon many factors: load profile; wind regime; insolation; cost and availability of backup power; the relative costs of wind rotor area, array area, and storage; and subsystem efficiency factors. Examples of optimized hybrid systems for a range of photovoltaic costs and estimated wind and storage costs are shown for an Ely, NV, application, where backup power is allowed to supply 5% of the total annual load.

Castle, J. A.; Kallis, J. M.; Moite, S. M.; Marshall, N. A.

49

Dynamic response of a stand-alone wind energy conversion system with battery energy storage to a wind gust  

Microsoft Academic Search

A mathematical model of each element of a stand-alone wind energy conversion system is developed. The model variables are expressed in the d-q rotor reference frame. The wind turbine was considered as the only source of power in this study. Using this model, the system response to a recorded wind gust is investigated by calculating the generator current, the rectifier

Bogdan S. Borowy; Ziyad M. Salameh

1997-01-01

50

Development of control scheme for a stand-alone wind system: Wind turbine emulated using DC motor  

Microsoft Academic Search

The burgeoning price of conventional sources have made it costlier in meeting load demand for stand-alone applications. So renewable sources, which are abundantly available have gained immense value in powering such remote locations. Wind energy is one of the proven technologies. This paper describes the implementation of a control scheme tested for a wind energy conversion system (WECS) with a

Aradhya S. Satpathy; N. C. Sahoo

2012-01-01

51

Low cost stand-alone ghost cancellation system  

Microsoft Academic Search

A new low cost ghost cancellation system is being developed for the consumer market that uses the high energy US reference signal to provide excellent cancellation of ghosts. The complete system consists of 3 ICs. This paper describes how these ICs work together to cancel ghosts without the need for micro-controllers, DSPs, or external control systems

Larry Johnson; Steve McNay; Ray Hill; David Greene; Yonatan Manor; Spencer Horowitz; Robert Casey; Kenji Murakami; Katsuaki Kaku; David Koo

1994-01-01

52

Optimization of Control Strategies for Stand-Alone Renewable Energy Systems with Hydrogen Storage  

Microsoft Academic Search

This paper presents a novel strategy, optimized by genetic algorithms, to control stand-alone hybrid renewable electrical systems with hydrogen storage. The strategy optimizes the control of the hybrid system minimizing the total cost throughout its lifetime. The optimized hybrid system can be composed of renewable sources (wind, PV and hydro), batteries, fuel cell, AC generator, and electrolyzer. If the renewable

Rodolfo Dufo-López; José L. Bernal-Agustín; Javier Contreras

2007-01-01

53

Design of a stand alone system with renewable energy sources using trade off methods  

Microsoft Academic Search

The authors present an application of recent theoretical advances in multiobjective planning under uncertainty, in the design of a stand-alone system with renewable energy sources. The system under design consists of a wind energy plant, a solar plant, and an storage battery. Time series data on wind, insolation, and load for the site of interest are assumed to be available.

E. S. Gavanidous; A. G. Bakirtzis

1992-01-01

54

COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES  

E-print Network

COMPRESSED-AIR ENERGY STORAGE SYSTEMS FOR STAND-ALONE OFF-GRID PHOTOVOLTAIC MODULES Dominique. Preliminary results clearly establish that the prototype holds enormous promise as energy storage systems production, is critically dependent on the availability of cost-effective, energy- storage technologies

Deymier, Pierre

55

Energy management of hydrogen-based stand-alone renewable energy system by using boost and buck converters  

Microsoft Academic Search

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energy (RE). A stand-alone RE system based on energy storage in the form of hydrogen has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with an in-house designed control system and power conditioning devices. In this system the excess energy with respect to

Kodjo Agbossou; Sousso Kélouwani; Adil Anouar; Mohanlal Kolhe

2004-01-01

56

Effective voltage and frequency control strategy for a stand-alone system with induction generator\\/fuel cell\\/ultracapacitor  

Microsoft Academic Search

This paper proposes the control scheme for an AC-linked hybrid wind\\/fuel cell\\/ultracapacitor alternative energy system for a stand-alone operation. Due to the intermittent nature of power obtained from the wind turbine-generator system, Hydrogen\\/fuelcell(H2\\/FC) and ultracapacitor(UC)are introduced as main storage and buffer storage respectively, to supply the demand for all operating conditions. Fuelcell, by virtue of its inherent slow generator dynamics,

Netra GYAWALI; Yasuharu OHSAWA

2009-01-01

57

Charactrization of a Li-ion battery based stand-alone a-Si photovoltaic system  

NASA Astrophysics Data System (ADS)

The number of photovoltaic (PV) system installations is increasing rapidly. As more people learn about this versatile and often cost-effective power option, this trend will accelerate. This document presents a recommended design for a battery based stand-alone photovoltaic system (BSPV). BSPV system has the ability to be applied in different areas, including warning signals, lighting, refrigeration, communication, residential water pumping, remote sensing, and cathodic protection. The presented calculation method gives a proper idea for a system sizing technique. Based on application load, different scenarios are possible for designing a BSPV system. In this study, a battery based stand-alone system was designed. The electricity generation part is three a-Si panels, which are connected in parallel, and for the storage part LFP (lithium iron phosphate) battery was used. The high power LFP battery packs are 40 cells each 8S5P (configured 8 series 5 parallel). Each individual pack weighs 0.5 kg and is 25.6 V. In order to evaluate the efficiency of a-Si panels with respect to the temperature and the solar irradiation, cities of Istanbul, Ankara and Adana in Turkey were selected. Temperature and solar irradiation were gathered from reliable sources and by using translation equations, current and voltage output of panels were calculated. As a result of these calculations, current and energy outputs were computed by considering an average efficient solar irradiation time value per day in Turkey. The calculated power values were inserted to a battery cycler system, and the behavior of high power LFP batteries in a time sequence of 7.2 h was evaluated. The charging and discharging cycles were obtained and their behavior was discussed. According to the results, Istanbul has the lowest number of peak month's energy, it followed by Ankara, and ultimately Adana has the highest number of peak months and energy storage. It was observed during the tests that values up to 4 A was discharged by battery packages in a full discharge cycle depending on application and required load.

Hamid Vishkasougheh, Mehdi; Tunaboylu, Bahadir

2014-11-01

58

Optimal hydrogen production in a stand-alone renewable energy system  

Microsoft Academic Search

A stand-alone renewable wind-photovoltaic energy system can be used to meet the energy requirements of off-grid remote area applications. Such a system has been developed and successfully tested at the Hydrogen Research Institute (HRI). In the HRFs system the excess electrical energy with respect to load demand, is transformed and stored as hydrogen gas via an electrolyzer. The stored hydrogen

Kodjo Agbossou; M. L. Doumbia; A. Anouar

2005-01-01

59

Space crew radiation exposure analysis system based on a commercial stand-alone CAD system  

NASA Technical Reports Server (NTRS)

Major improvements have recently been completed in the approach to spacecraft shielding analysis. A Computer-Aided Design (CAD)-based system has been developed for determining the shielding provided to any point within or external to the spacecraft. Shielding analysis is performed using a commercially available stand-alone CAD system and a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design projects such as a Mars transfer habitat, pressurized lunar rover, and the redesigned Space Station. Results of these analyses are provided to demonstrate the applicability and versatility of the system.

Appleby, Matthew H.; Golightly, Michael J.; Hardy, Alva C.

1992-01-01

60

Space crew radiation exposure analysis system based on a commercial stand-alone CAD system  

NASA Astrophysics Data System (ADS)

Major improvements have recently been completed in the approach to spacecraft shielding analysis. A Computer-Aided Design (CAD)-based system has been developed for determining the shielding provided to any point within or external to the spacecraft. Shielding analysis is performed using a commercially available stand-alone CAD system and a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design projects such as a Mars transfer habitat, pressurized lunar rover, and the redesigned Space Station. Results of these analyses are provided to demonstrate the applicability and versatility of the system.

Appleby, Matthew H.; Golightly, Michael J.; Hardy, Alva C.

1992-07-01

61

Design of stand-alone brackish water desalination wind energy system for Jordan  

SciTech Connect

More than 100 underground water wells drilled in Jordan are known to have brackish water with total desolved solids (TDS) over 1500 ppm but not greater than 4000 ppm. The world standard for potable water limits the TDS count to 500 ppm in addition to being free from live microorganisms or dangerous mineral and organic substances. A reverse osmosis desalination scheme powered by a stand-alone wind energy converter (WEC) is proposed to produce fresh water water from wells located in potentially high-wind sites. The purpose of this study if to present the main design parameters and economic estimates of a wind-assisted RO system using a diesel engine as the baseline energy source and an electric wind turbine for the wind energy source. It is found that brackish water pumping and desalinating using WECs costs 0.67 to 1.16 JD/m[sup 3] (JD = Jordanian Dinar, 1US$ = 0.68 JD), which is less than using conventional diesel engines especially in remote areas. In addition, the wind-reverse osmosis system becomes more economically feasible for higher annual production rates or in good wind regimes.

Habali, S.M.; Saleh, I.A.

1994-06-01

62

Stand-alone Photovoltaic System using an UPS Inverter and a Microcontrolled Battery Charger based on a Boost Converter with a 3 State-Commutation Cell  

Microsoft Academic Search

This paper presents a stand-alone photovoltaic energy system aimed for small power consumer applications in isolated areas of the countryside of Brazil. In order to develop a cost-effective and simple product, a double power conversion UPS (uninterruptible power supply) was analyzed and modified. A whole new battery charger was implemented using a PIC microcontroller equipped with a MPP seeking algorithm,

Samuel V. Araújo; René P. Torrico-Bascopé; Fernando L. M. Antunes; Edílson Mineiro Sá

2006-01-01

63

System Simulation by Recursive Feedback: Coupling a Set of Stand-Alone Subsystem Simulations  

NASA Technical Reports Server (NTRS)

Conventional construction of digital dynamic system simulations often involves collecting differential equations that model each subsystem, arran g them to a standard form, and obtaining their numerical gin solution as a single coupled, total-system simultaneous set. Simulation by numerical coupling of independent stand-alone subsimulations is a fundamentally different approach that is attractive because, among other things, the architecture naturally facilitates high fidelity, broad scope, and discipline independence. Recursive feedback is defined and discussed as a candidate approach to multidiscipline dynamic system simulation by numerical coupling of self-contained, single-discipline subsystem simulations. A satellite motion example containing three subsystems (orbit dynamics, attitude dynamics, and aerodynamics) has been defined and constructed using this approach. Conventional solution methods are used in the subsystem simulations. Distributed and centralized implementations of coupling have been considered. Numerical results are evaluated by direct comparison with a standard total-system, simultaneous-solution approach.

Nixon, D. D.

2001-01-01

64

Stand alone computer system to aid the development of Mirror Fusion Test Facility rf heating systems  

SciTech Connect

The Mirror Fusion Test Facility (MFTF-B) control system architecture requires the Supervisory Control and Diagnostic System (SCDS) to communicate with a LSI-11 Local Control Computer (LCC) that in turn communicates via a fiber optic link to CAMAC based control hardware located near the machine. In many cases, the control hardware is very complex and requires a sizable development effort prior to being integrated into the overall MFTF-B system. One such effort was the development of the Electron Cyclotron Resonance Heating (ECRH) system. It became clear that a stand alone computer system was needed to simulate the functions of SCDS. This paper describes the hardware and software necessary to implement the SCDS Simulation Computer (SSC). It consists of a Digital Equipment Corporation (DEC) LSI-11 computer and a Winchester/Floppy disk operating under the DEC RT-11 operating system. All application software for MFTF-B is programmed in PASCAL, which allowed us to adapt procedures originally written for SCDS to the SSC. This nearly identical software interface means that software written during the equipment development will be useful to the SCDS programmers in the integration phase.

Thomas, R.A.

1983-12-01

65

Performance of a 268Wp stand-alone PV system test facility  

SciTech Connect

This paper reports on studies carried out on a 268 Wp stand-alone PV test facility installed at the University of Ghana. Parameters measured include solar irradiance, ambient temperature, cell temperature, array voltage, battery voltage, and energy output from array. An automatic data acquisition system was used to record the data. The purpose of this study was to determine the effect on performance of a PV array due to seasonal climatic changes: for example, effect due to dust during the period when dust-laden winds blow from the Sahara desert to most sub-saharan West African countries. The reduced intensity of the solar radiation as would be expected reduced the total array output during the harmattan and the rainy seasons. No visible changes were observed in the PV modules themselves over the period of study, but one of the junction boxes attached to the modules had become severely corroded.

Adanu, K.G. [Univ. of Ghana, Legon-Accra (Ghana)

1994-12-31

66

ACE16k based stand-alone system for real-time pre-processing tasks  

NASA Astrophysics Data System (ADS)

This paper describes the design of a programmable stand-alone system for real time vision pre-processing tasks. The system's architecture has been implemented and tested using an ACE16k chip and a Xilinx xc4028xl FPGA. The ACE16k chip consists basically of an array of 128x128 identical mixed-signal processing units, locally interacting, which operate in accordance with single instruction multiple data (SIMD) computing architectures and has been designed for high speed image pre-processing tasks requiring moderate accuracy levels (7 bits). The input images are acquired using the optical input capabilities of the ACE16k chip, and after being processed according to a programmed algorithm, the images are represented at real time on a TFT screen. The system is designed to store and run different algorithms and to allow changes and improvements. Its main board includes a digital core, implemented on a Xilinx 4028 Series FPGA, which comprises a custom programmable Control Unit, a digital monochrome PAL video generator and an image memory selector. Video SRAM chips are included to store and access images processed by the ACE16k. Two daughter boards hold the program SRAM and a video DAC-mixer card is used to generate composite analog video signal.

Carranza, Luis; Jimenez-Garrido, Francisco; Linan-Cembrano, Gustavo; Roca, Elisenda; Espejo Meana, Servando; Rodriguez-Vazquez, Angel

2005-06-01

67

The Stand-Alone Microprocessor System: A Valuable Tool in College Admissions and Recruitment.  

ERIC Educational Resources Information Center

The stand-alone microprocessor is seen as one innovative tool that can be used both in the organizational management of decline and in meeting specific organizational needs such as those of the admissions director and staff. The term "microprocessor" is defined. (MLW)

Garrett, Larry Neal

1983-01-01

68

A stand-alone demography and landscape structure module for Earth system models  

NASA Astrophysics Data System (ADS)

We propose and demonstrate a new approach for the simulation of woody ecosystem stand dynamics, demography and disturbance-mediated heterogeneity suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any earth system model (Haverd et al., 2013). The approach is encoded in a model called Populations-Order-Physiology (POP). We demonstrate the behaviour and performance of POP coupled to the Community Atmosphere Biosphere Land Exchange model (CABLE) for two contrasting applications: (i) to the Northern Australian Tropical Transect, featuring gradients in savanna vegetation cover, rainfall and fire disturbance and (ii) to a set of globally distributed forest locations coinciding with observations of forest biomass allometry. Along the Northern Australian Tropical Transect, CABLE-POP is able to simultaneously reproduce observation-based estimates of key functional and structural variables, namely gross primary production, tree foliage projective cover, basal area and maximum tree height. This application particularly demonstrates the ability of POP to quantify the contributions of drought and fire to tree mortality. Drought is manifested as an increase in mortality due to a decline in growth efficiency, while fires are treated as partial disturbance events, with tree mortality depending on tree size and fire intensity. In the application to global forests, POP is integrated with global forest data by calibrating it against paired observations of stem biomass and number density. The calibrated POP model is then coupled with CABLE and the coupled model is evaluated against leaf-stem allometry observations from forest stands ranging in age from 20 to 400 years. Results indicate that, in contrast to simulations from many global land surface models (Wolf et al., 2011), simulated biomass pools conform well with observed allometry. We conclude that POP, which can readily be coupled to the terrestrial carbon cycle component of any LSM, represents a significant advance in our ability to use in-situ and remotely sensed observations of biomass and individual level parameters (e.g. crown-size, tree-height, stem diameter) as constraints on the terrestrial carbon cycle. Haverd, V., B. Smith, G. Cook, P. Briggs, L. Nieradzik, S. Roxburgh, A. Liedloff, C. Meyer, and J. G. Canadell, A stand-alone tree demography and landscape structure module for Earth system models, submitted to Geophys. Res. Let., 2013 Wolf, A., P. Ciais, V. Bellassen, N. Delbart, C.B. Field, and J.A. Berry, Forest biomass allometry in global land surface models, Global Biogeochem. Cycles, 25, GB3015, doi:10.1029/2010GB003917, 2011

Nieradzik, L. P.; Haverd, V.; Smith, B.; Cook, G. D.; Briggs, P.; Roxburgh, S.; Liedloff, A.; Meyer, C.; Canadell, J.

2013-12-01

69

Honeywell Parallon Stand-alone Tests Honeywell Stand-alone Tests  

E-print Network

Appendix E Honeywell Parallon Stand-alone Tests 5/2/2001 #12;Honeywell Stand-alone Tests 5 Figure E-1: Ramp Down Tests ­ Power and Shaft Speed ­ kW and kVAR Steps #12;Honeywell Stand-alone Tests 5 Down Tests ­ Power and Turbine Exit Temperature ­ kW and kVAR Steps #12;Honeywell Stand-alone Tests 5

70

Low-cost stand-alone system for eddy current testing of metallic non-ferromagnetic plates  

Microsoft Academic Search

This paper describes a nondestructive testing equipment designed with the purpose of being low-cost and able to work in a stand-alone way. The main feature is related to the integration of an eddy-current probe using a giant magnetoresistance (GMR) sensor with a computer mouse to be used as a positioning system. The system was constructed and tested. The results that

T. Jorge Rocha; A. Lopes Ribeiro; H. M. Geirinhas Ramos

2011-01-01

71

Possible use of vanadium redox-flow batteries for energy storage in small grids and stand-alone photovoltaic systems  

Microsoft Academic Search

The all-vanadium redox-flow battery is a promising candidate for load leveling and seasonal energy storage in small grids and stand-alone photovoltaic systems. The reversible cell voltage of 1.3 to 1.4V in the charged state allows the use of inexpensive active and structural materials. In this work, studies on the performance of inexpensive active materials for use in vanadium redox-flow batteries

Ludwig Joerissen; Juergen Garche; Ch. Fabjan; G. Tomazic

2004-01-01

72

Capstone LP Stand-alone Tests Capstone Stand-alone Tests  

E-print Network

Appendix D Capstone LP Stand-alone Tests 3/20/2001 #12;Capstone Stand-alone Tests 3/20/2001 -5: Ramp Tests ­ Power and Shaft Speed ­ 4 kW Steps #12;Capstone Stand-alone Tests 3/20/2001 -5,000 0 5 and Turbine Exit Temperature ­ 4 kW Steps #12;Capstone Stand-alone Tests 3/20/2001 -5,000 0 5,000 10,000 15

73

Possible use of vanadium redox-flow batteries for energy storage in small grids and stand-alone photovoltaic systems  

NASA Astrophysics Data System (ADS)

The all-vanadium redox-flow battery is a promising candidate for load leveling and seasonal energy storage in small grids and stand-alone photovoltaic systems. The reversible cell voltage of 1.3 to 1.4 V in the charged state allows the use of inexpensive active and structural materials. In this work, studies on the performance of inexpensive active materials for use in vanadium redox-flow batteries are reported. Additionally, a cost analysis for a load leveling and a seasonal energy storage system is given based on a flow battery technology well established in Zn-flow batteries.

Joerissen, Ludwig; Garche, Juergen; Fabjan, Ch.; Tomazic, G.

74

Stand-Alone Front-End System for High-Frequency, High-Frame-Rate Coded Excitation Ultrasonic Imaging  

PubMed Central

A stand-alone front-end system for high-frequency coded excitation imaging was implemented to achieve a wider dynamic range. The system included an arbitrary waveform amplifier, an arbitrary waveform generator, an analog receiver, a motor position interpreter, a motor controller and power supplies. The digitized arbitrary waveforms at a sampling rate of 150 MHz could be programmed and converted to an analog signal. The pulse was subsequently amplified to excite an ultrasound transducer, and the maximum output voltage level achieved was 120 Vpp. The bandwidth of the arbitrary waveform amplifier was from 1 to 70 MHz. The noise figure of the preamplifier was less than 7.7 dB and the bandwidth was 95 MHz. Phantoms and biological tissues were imaged at a frame rate as high as 68 frames per second (fps) to evaluate the performance of the system. During the measurement, 40-MHz lithium niobate (LiNbO3) single-element lightweight (<0.28 g) transducers were utilized. The wire target measurement showed that the ?6-dB axial resolution of a chirp-coded excitation was 50 µm and lateral resolution was 120 µm. The echo signal-to-noise ratios were found to be 54 and 65 dB for the short burst and coded excitation, respectively. The contrast resolution in a sphere phantom study was estimated to be 24 dB for the chirp-coded excitation and 15 dB for the short burst modes. In an in vivo study, zebrafish and mouse hearts were imaged. Boundaries of the zebrafish heart in the image could be differentiated because of the low-noise operation of the implemented system. In mouse heart images, valves and chambers could be readily visualized with the coded excitation. PMID:23443698

Park, Jinhyoung; Hu, Changhong; Shung, K. Kirk

2012-01-01

75

Optimal design of a reliable hydrogen-based stand-alone wind\\/PV generation system  

Microsoft Academic Search

A hybrid wind\\/photovoltaic\\/fuel cell generation system is designed to supply power demand. The aim of this design is minimization of overall cost of generation scheme over 20 years of operation. Optimization problem is subject to reliable supply of demand. The system components and radiation and wind speed datasets are assumed to be fully deterministic. System costs involve investments, operation and

A. Kashefi Kaviani; G. H. Riahy; S. M. Kouhsarj

2008-01-01

76

Supervisor control for a stand-alone hybrid generation system using wind and photovoltaic energy  

Microsoft Academic Search

A comprehensive supervisor control for a hybrid system that comprises wind and photovoltaic generation subsystems, a battery bank, and an ac load is developed in this paper. The objectives of the supervisor control are, primarily, to satisfy the load power demand and, second, to maintain the state of charge of the battery bank to prevent blackout and to extend the

Fernando Valenciaga; Paul F. Puleston

2005-01-01

77

Stand-alone development system using a KIM-1 microcomputer module  

NASA Technical Reports Server (NTRS)

A small microprocessor-based system designed to: contain all or most of the interface hardware, designed to be easy to access and modify the hardware, to be capable of being strapped to the seat of a small general aviation aircraft, and to be independent of the aircraft power system is described. The system is used to develop a low cost Loran C sensor processor, but is designed such that the Loran interface boards may be removed and other hardware interfaces inserted into the same connectors. This flexibility is achieved through memory-mapping techniques into the microprocessor.

Nickum, J. D.

1978-01-01

78

Control of Stand-Alone Photovoltaic System Using Fuzzy-Logic Controller  

E-print Network

and acceptable satisfactions rates they do not perform an optimisation of the PV plant for the local climate conditions. The power supplied by solar arrays depends on the radiation, temperature and array voltage, the operation point of a load connected...

Mellit, A.; Benghanme, M.; Arab, A. H.; Guessoum, A.

2004-01-01

79

Design of a predictive control strategy for integration of stand-alone wind\\/diesel system  

Microsoft Academic Search

Power control of variable speed wind turbines coupled with squirrel cage induction generators is difficult and suffers from some fundamental problems. If this type of wind turbines are applied to remote areas, they cannot stabilize frequency and voltage of the grid in acceptable limits. Changes in the load during one day also make this problem harder to deal with. In

Behzad Sedaghat; Abolfazl Jalilvand; Reza Noroozian

2010-01-01

80

5 Wp PV module-based stand-alone solar tracking system  

Microsoft Academic Search

5 Watt-PV module is utilized for tracking solar oven concentrator system with 2.6 kW\\/sub th\\/ capacity and 200 Kg weight. The tracking system follows the sun autonomously in altitude and azimuth using only 5 Watt-peak PV solar module as a tracking energy source. The tracking system is driven by means of two 12 DCV motors of 36 W each, and

J. A. Urbano; Y. Matsumoto; R. Asomoza; F. J. Aceves; A. Sotelo; A. Jacome

2003-01-01

81

Optimal sizing of stand-alone hybrid wind\\/PV system with battery storage  

Microsoft Academic Search

In this paper, a new methodology developed to design a hybrid wind\\/photovoltaic (wind\\/PV) system, is presented. Based on an optimization process using a deterministic algorithm, the developed methodology helps the authors to obtain the optimal number and type of PV panels, wind turbines and storage units ensuring that the system total cost is minimized while guaranteeing the permanent availability of

Rachid BELFKIRA; Omessad HAJJI; Cristian NICHITA; Georges BARAKAT

2007-01-01

82

Design and analysis of stand-alone hydrogen energy systems with different renewable sources  

Microsoft Academic Search

One of the most interesting developments of energy systems based on the utilization of hydrogen is their integration with renewable sources of energy (RES). In fact, hydrogen can operate as a storage and carrying medium of these primary sources. The design and operation of the system could change noticeably, depending on the type and availability of the primary source. In

Massimo Santarelli; Sara Macagno

2004-01-01

83

Robust optimal sizing of an hybrid energy stand-alone system  

E-print Network

Mar 24, 2014 ... tem composed of wind turbines, solar photovoltaic panels and batteries. To compensate for a ... account of the stochastic behavior of the solar and wind energy production and also of the ...... pv/wind system. Energy Policy,.

2014-03-24

84

Stand-alone Laboratory Information Systems Versus Laboratory Modules Incorporated in the Electronic Health Record.  

PubMed

The increasing availability of laboratory information management modules within enterprise electronic health record solutions has resulted in some institutional administrators deciding which laboratory information system will be used to manage workflow within the laboratory, often with minimal input from the pathologists. This article aims to educate pathologists on many of the issues and implications this change may have on laboratory operations, positioning them to better evaluate and represent the needs of the laboratory during this decision-making process. The experiences of the authors, many of their colleagues, and published observations relevant to this debate are summarized. There are multiple dimensions of the interdependency between the pathology laboratory and its information system that must be factored into the decision. Functionality is important, but management authority and gap-ownership are also significant elements to consider. Thus, the pathologist must maintain an active role in the decision-making process to ensure the success of the laboratory. PMID:25724027

Sinard, John H; Castellani, William J; Wilkerson, Myra L; Henricks, Walter H

2015-03-01

85

PORTABLE STAND-ALONE INSTRUMENTATION FOR INTRACELLULAR IN VITRO RECORDINGS  

E-print Network

PORTABLE STAND-ALONE INSTRUMENTATION FOR INTRACELLULAR IN VITRO RECORDINGS N. Peixoto, J. Mavoori of Washington, Friday Harbor, WA 98250, USA nathalia@lme.usp.br Abstract - A portable stand-alone system amplifier and the portable stand-alone circuit, intracellular signals are acquired for more than 20 hours

86

Honeywell Parallon Delta Measurement Stand-alone Tests Honeywell Stand-alone Delta Tests  

E-print Network

Appendix F Honeywell Parallon Delta Measurement Stand-alone Tests 6/20/2001 #12;Honeywell Stand-alone Delta Tests 6/20/2001 -10,000 0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 0 50 100 150 200 (VAR) Engine Speed Figure F-1: Ramp Tests ­ Power and Shaft Speed ­ Delta Measurements #12;Honeywell

87

Estimation of the potential array output charge in the performance analysis of stand-alone photovoltaic systems without MPPT (Case study: Mediterranean climate)  

SciTech Connect

The potential array output energy, E{sub P}, stated by the Joint Research Centre (JRC) in their European Guidelines for the Assessment of Photovoltaic Plants and the IEC Standard 61724 does not estimate properly the potential array output of stand-alone photovoltaic (SAPV) systems without maximum power point tracker (MPPT) as it is the case for SAPV systems with MPPT and grid connected systems. In this way, the main purpose of this paper is to validate an expression that compromises simplicity and accuracy when estimating the potential array output of SAPV systems without MPPT. This issue can be of high interest to photovoltaic (PV) practitioners and experts as it can improve the analysis performance of this type of systems, helping to discriminate better the different losses in this kind of systems. Furthermore, a study of the array potential estimation through different expressions will be developed in order to evaluate which matches better the array potential output in SAPV system without MPPT. Although the analysis will be focused especially in Mediterranean climates, it will be derived some general conclusions that can be considered in other climates. (author)

Munoz, F.J.; Echbarthi, I.; Nofuentes, G.; Fuentes, M.; Aguilera, J. [Grupo IDEA, Departamento de Ingenieria Electronica y Automatica, Universidad de Jaen, Campus las Lagunillas, 23071 - Jaen (Spain)

2009-11-15

88

Comparison between solar utilization of a closed microalgae-based bio-loop and that of a stand-alone photovoltaic system.  

PubMed

This study compared the solar energy utilization of a closed microalgae-based bio-loop for energy efficient production of biogas with fertilizer recovery against that of a stand-alone photovoltaic (PV) system. The comparison was made from the perspective of broad life cycle assessment, simultaneously taking exergy to be the functional unit. The results indicated that the bio-loop was more environmentally competitive than an equivalent stand-alone PV system, but had higher economic cost due to high energy consumption during the operational phase. To fix the problem, a patented, interior pressurization scheduling method was used to operate the bio-loop, with microalgae and aerobic bacterial placed together in the same reactor. As a result, the overall environmental impact and total investment were respectively reduced by more than 75% and 84%, a vast improvement on the bio-loop. PMID:25465781

Jin, Qiang; Chen, Lei; Li, Aimin; Liu, Fuqiang; Long, Chao; Shan, Aidang; Borthwick, Alistair G L

2015-05-01

89

STAND ALONE graphics; now more than ever  

Microsoft Academic Search

The role seen for computer graphics in studying proteins and in aiding their structure determination through interpretation of electron density maps resulting from x-ray (and now neutron) diffraction has changed little since the design of the first molecular graphics system by Leventhal?. The obvious definition of a STAND ALONE SYSTEM has likewise remained unchanged; computers, however, have not. The last

C. D. Barry

1975-01-01

90

Novel Technique of Sizing the Stand-Alone Photovoltaic Systems Using the Radial Basis Function Neural Networks: Application in Isolated Sites  

E-print Network

, longitude, the load, the characteristics of stand alone PV system, the inclination of the panels and to take very much computing time for estimation of optimal couple. On the other hand, the model that we developed allows estimating the PV-array area... and the storage capacity from a minimum input data (altitude, longitude) based on the optimal sizing couples and does not take much time for simulation. The advantage of this model is to estimate of the PV-array area and the storage capacity in any site...

Mellit, A.; Benghanme, M.; Arab, A. H.; Guessoum, A.

2004-01-01

91

A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system  

PubMed Central

One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt. PMID:25685507

Mohamed, Ahmed F.; Elarini, Mahdi M.; Othman, Ahmed M.

2013-01-01

92

A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system.  

PubMed

One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt. PMID:25685507

Mohamed, Ahmed F; Elarini, Mahdi M; Othman, Ahmed M

2014-05-01

93

Ris-R-1480(EN) Stand-alone version of the 11kW Gaia  

E-print Network

tested both as a stand- alone unit and in parallel with a diesel genset. For system wide power quality.2 Overall operating conditions requirements 7 3.3 Power quality requirements 8 3.4 Connection of large loads 8 3.5 Protection and other operating conditions 8 3.6 Power system configurations 8 4 Technical

94

The Compact Disk-Circulation System Interface at the Tacoma Public Library: Beyond Stand-Alone CD-ROM.  

ERIC Educational Resources Information Center

Describes the development of a CD-ROM public access catalog (CD-PAC)-circulation system interface at the Tacoma (Washington) Public Library. Cost considerations, advantages and disadvantages, access time, and currency of the CD-PAC are discussed. Sidebars cover CD-ROM and the library market, future technologies, and comparisons of prices for…

Hegarty, Kevin

1988-01-01

95

Evaluation of a stand-alone computer-aided detection system for acute intra-cranial hemorrhage in emergency environments  

NASA Astrophysics Data System (ADS)

Acute intra-cranial hemorrhage (AIH) may result from traumatic brain injury (TBI). Successful management of AIH depends heavily on the speed and accuracy of diagnosis. Timely diagnosis in emergency environments in both civilian and military settings is difficult primarily due to severe time restraints and lack of resources. Often, diagnosis is performed by emergency physicians rather than trained radiologists. As a result, added support in the form of computer-aided detection (CAD) would greatly enhance the decision-making process and help in providing faster and more accurate diagnosis of AIH. This paper discusses the implementation of a CAD system in an emergency environment, and its efficacy in aiding in the detection of AIH.

Fernandez, James; Deshpande, Ruchi; Wang, Ximing; Liu, Brent; Brazaitis, Michael; Munter, Fletcher; Liu, Margaret

2011-03-01

96

A stand-alone tree demography and landscape structure module for Earth system models: integration with global forest data  

NASA Astrophysics Data System (ADS)

Poorly constrained rates of biomass turnover are a key limitation of Earth system models (ESM). In light of this, we recently proposed a new approach encoded in a model called Populations-Order-Physiology (POP), for the simulation of woody ecosystem stand dynamics, demography and disturbance-mediated heterogeneity. POP is suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any ESM. POP bridges the gap between first generation Dynamic Vegetation Models (DVMs) with simple large-area parameterisations of woody biomass (typically used in current ESMs) and complex second generation DVMs, that explicitly simulate demographic processes and landscape heterogeneity of forests. The key simplification in the POP approach, compared with second-generation DVMs, is to compute physiological processes such as assimilation at grid-scale (with CABLE or a similar land surface model), but to partition the grid-scale biomass increment among age classes defined at sub grid-scale, each subject to its own dynamics. POP was successfully demonstrated along a savanna transect in northern Australia, replicating the effects of strong rainfall and fire disturbance gradients on observed stand productivity and structure. Here, we extend the application of POP to a range of forest types around the globe, employing paired observations of stem biomass and density from forest inventory data to calibrate model parameters governing stand demography and biomass evolution. The calibrated POP model is then coupled to the CABLE land surface model and the combined model (CABLE-POP) is evaluated against leaf-stem allometry observations from forest stands ranging in age from 3 to 200 yr. Results indicate that simulated biomass pools conform well with observed allometry. We conclude that POP represents a preferable alternative to large-area parameterisations of woody biomass turnover, typically used in current ESMs.

Haverd, V.; Smith, B.; Nieradzik, L. P.; Briggs, P. R.

2014-02-01

97

Capstone/Capstone Parallel Stand-alone Tests Capstone/Capstone Parallel Tests  

E-print Network

Appendix G Capstone/Capstone Parallel Stand-alone Tests 4/17/2001 #12;Capstone/Capstone Parallel Seconds Real(W)&Reactive(VAR)Power Load Bank 3Ã? Real Power (W) Load Bank 3Ã? Reactive Power (VAR) Stand-alone(W)&Reactive(VAR)Power Load Bank 3Ã? Real Power (W) Load Bank 3Ã? Reactive Power (VAR) Stand-alone Power (W) Grid-connect Power

98

DOE and AID stand-alone photovoltaic activities  

NASA Technical Reports Server (NTRS)

The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system activities sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, PV-powered medical refrigerators in six countries, PV system microprocessor control development activities and PV-hybrid system assessments. The AID project includes a large village system in Tunisia, a water pumping/grain grinding project in Upper Volta, five medical clinics in four countries, PV-powered remote earth station application. These PV activities and summarizes significant findings to data are reviewed.

Bifano, W. J.; Ratajczak, A. F.

1983-01-01

99

DOE and AID stand-alone photovoltaic activities  

NASA Astrophysics Data System (ADS)

The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system activities sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, PV-powered medical refrigerators in six countries, PV system microprocessor control development activities and PV-hybrid system assessments. The AID project includes a large village system in Tunisia, a water pumping/grain grinding project in Upper Volta, five medical clinics in four countries, PV-powered remote earth station application. These PV activities and summarizes significant findings to data are reviewed.

Bifano, W. J.; Ratajczak, A. F.

100

The Impact of Course Delivery Systems on Student Achievement and Sense of Community: A Comparison of Learning Community versus Stand-Alone Classroom Settings in an Open-Enrollment Inner City Public Community College  

ERIC Educational Resources Information Center

This study examined the effects of two types of course delivery systems (learning community classroom environments versus stand-alone classroom environments) on the achievement of students who were simultaneously enrolled in remedial and college-level social science courses at an inner city open-enrollment public community college. This study was…

Bandyopadhyay, Pamela

2010-01-01

101

Capstone Low Pressure Grid-connect Tests Capstone LP Stand-alone Tests  

E-print Network

Appendix B Capstone Low Pressure Grid-connect Tests 10/25/2000 #12;Capstone LP Stand-alone Tests 10) Figure B-1: Power and Shaft Speed ­ 10 kW Steps #12;Capstone LP Stand-alone Tests 10/25/2000 0 5000 10000) Figure B-2: Power and Turbine Exit Temperature ­ 10 kW Steps #12;Capstone LP Stand-alone Tests 10

102

Application of valve-regulated lead-acid batteries for storage of solar electricity in stand-alone photovoltaic systems in the northwest areas of China  

Microsoft Academic Search

Photovoltaic (PV) installations for solar electric power generation are being established rapidly in the northwest areas of China, and it is increasingly important for these power systems to have reliable and cost effective energy storage. The lead-acid battery is the more commonly used storage technology for PV systems due to its low cost and its wide availability. However, analysis shows

Shounan Hua; Qingshen Zhou; Delong Kong; Jianping Ma

2006-01-01

103

TESTING THE STAND-ALONE MICROBEAM AT COLUMBIA UNIVERSITY  

E-print Network

TESTING THE STAND-ALONE MICROBEAM AT COLUMBIA UNIVERSITY G. GartyÃ? , G. J. Ross, A. W. Bigelow, G. Broadway, Irvington, NY 10533, USA The stand-alone microbeam at Columbia University presents a novel or using an isotopic source, is being developed. The `so-called' stand alone microbeam (SAM) consists

104

Design requirements for a stand alone EUV interferometer  

NASA Astrophysics Data System (ADS)

EUV lithography is expected to be inserted for the 32/22 nm nodes with possible extension below. EUV resist availability remains one of the main issues to be resolved. There is an urgent need to provide suitable tools to accelerate resist development and to achieve resolution, LER and sensitivity specifications simultaneously. An interferometer lithography tool offers advantages regarding conventional EUV exposure tool. It allows the evaluation of resists, free from the deficiencies of optics and mask which are limiting the achieved resolution. Traditionally, a dedicated beam line from a synchrotron, with limited access, is used as a light source in EUV interference lithography. This paper identifies the technology locks to develop a stand alone EUV interferometer using a compact EUV source. It will describe the theoretical solutions adopted and especially look at the feasibility according to available technologies. EUV sources available on the market have been evaluated in terms of power level, source size, spatial coherency, dose uniformity, accuracy, stability and reproducibility. According to the EUV source characteristics, several optic designs were studied (simple or double gratings). For each of these solutions, the source and collimation optic specifications have been determined. To reduce the exposure time, a new grating technology will also be presented allowing to significantly increasing the transmission system efficiency. The optical grating designs were studied to allow multi-pitch resolution print on the same exposure without any focus adjustment. Finally micro mechanical system supporting the gratings was studied integrating the issues due to vacuum environment, alignment capability, motion precision, automation and metrology to ensure the needed placement control between gratings and wafer. A similar study was carried out for the collimation-optics mechanical support which depends on the source characteristics.

Michallon, Ph.; Constancias, C.; Lagrange, A.; Dalzotto, B.

2008-03-01

105

CAD-based stand-alone spacecraft radiation exposure analysis system: An application of the early man-tended Space Station  

NASA Technical Reports Server (NTRS)

Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A computer-aided design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. Shielding analysis is performed using a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design programs such as a Mars transfer habitat, pressurized lunar rover, and the redesigned international Space Station. Results of analysis performed for the Space Station astronaut exposure assessment are provided to demonastrate the applicability and versatility of the system.

Appleby, M. H.; Golightly, M. J.; Hardy, A. C.

1993-01-01

106

CAD-based stand-alone spacecraft radiation exposure analysis system: An application of the early man-tended Space Station  

NASA Astrophysics Data System (ADS)

Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A computer-aided design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. Shielding analysis is performed using a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design programs such as a Mars transfer habitat, pressurized lunar rover, and the redesigned international Space Station. Results of analysis performed for the Space Station astronaut exposure assessment are provided to demonastrate the applicability and versatility of the system.

Appleby, M. H.; Golightly, M. J.; Hardy, A. C.

107

A stand-alone tree demography and landscape structure module for Earth system models: integration with inventory data from temperate and boreal forests  

NASA Astrophysics Data System (ADS)

Poorly constrained rates of biomass turnover are a key limitation of Earth system models (ESMs). In light of this, we recently proposed a new approach encoded in a model called Populations-Order-Physiology (POP), for the simulation of woody ecosystem stand dynamics, demography and disturbance-mediated heterogeneity. POP is suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any ESM. POP bridges the gap between first-generation dynamic vegetation models (DVMs) with simple large-area parameterisations of woody biomass (typically used in current ESMs) and complex second-generation DVMs that explicitly simulate demographic processes and landscape heterogeneity of forests. The key simplification in the POP approach, compared with second-generation DVMs, is to compute physiological processes such as assimilation at grid-scale (with CABLE (Community Atmosphere Biosphere Land Exchange) or a similar land surface model), but to partition the grid-scale biomass increment among age classes defined at sub-grid-scale, each subject to its own dynamics. POP was successfully demonstrated along a savanna transect in northern Australia, replicating the effects of strong rainfall and fire disturbance gradients on observed stand productivity and structure. Here, we extend the application of POP to wide-ranging temporal and boreal forests, employing paired observations of stem biomass and density from forest inventory data to calibrate model parameters governing stand demography and biomass evolution. The calibrated POP model is then coupled to the CABLE land surface model, and the combined model (CABLE-POP) is evaluated against leaf-stem allometry observations from forest stands ranging in age from 3 to 200 year. Results indicate that simulated biomass pools conform well with observed allometry. We conclude that POP represents an ecologically plausible and efficient alternative to large-area parameterisations of woody biomass turnover, typically used in current ESMs.

Haverd, V.; Smith, B.; Nieradzik, L. P.; Briggs, P. R.

2014-08-01

108

29 CFR 778.104 - Each workweek stands alone.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Each workweek stands alone. 778.104 Section 778.104 Labor Regulations Relating...Requirements Introductory § 778.104 Each workweek stands alone. The Act takes a single workweek as its standard and...

2011-07-01

109

29 CFR 778.104 - Each workweek stands alone.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Each workweek stands alone. 778.104 Section 778.104 Labor Regulations Relating...Requirements Introductory § 778.104 Each workweek stands alone. The Act takes a single workweek as its standard and...

2014-07-01

110

29 CFR 778.104 - Each workweek stands alone.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Each workweek stands alone. 778.104 Section 778.104 Labor Regulations Relating...Requirements Introductory § 778.104 Each workweek stands alone. The Act takes a single workweek as its standard and...

2012-07-01

111

29 CFR 778.104 - Each workweek stands alone.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Each workweek stands alone. 778.104 Section 778.104 Labor Regulations Relating...Requirements Introductory § 778.104 Each workweek stands alone. The Act takes a single workweek as its standard and...

2013-07-01

112

Collaborative Eclipse Plug-in Integration Architecture for stand alone  

E-print Network

Collaborative Eclipse Plug-in Integration Architecture for stand alone programs (agents) A project Report Summary By Shajil K Kalathil (04/29/2005) #12;Table of Contents 1. Eclipse Platform Overview................................................................ 3 2. Eclipse Cross Section

Jones, Edward

113

Efficient line-connected voltage-conditioner with minimum disturbance transfer to stand-alone mode  

NASA Astrophysics Data System (ADS)

This thesis deals with a novel efficient line-connected voltage-conditioning system (VCS) with minimum disturbance transfer to stand-alone mode. The proposed VCS is used for conditioning a terminal voltage of the critical load on the equipment level. It offers advantages over a conventional rectifier-inverter system in terms of efficiency/harmonic generation and over existing line-connected systems in terms of transfer time/dynamic response. To the author's best knowledge, the concept of a solid-state breaker realized with the controlled turn-on/turn-off switch has been introduced for the first time in this thesis. By using the proposed power converter topology, controller structure independent of the load parameters and line-disturbance detection method, the system conforms to the different susceptibility requirements of the critical equipment. A detailed power circuit and controller description of the proposed current-source-inverter voltage-conditioning system (CSI-VCS) are given. A steady-state analysis of the proposed system is performed including the higher order harmonics. A system controller is designed in order to achieve the two objectives that follow. The first objective is to provide the fast transfer from the line-connected mode to the stand-alone mode in the case of line disturbance. The second objective is to obtain the fast transient response under load disturbance and to provide, in the steady-state, the output voltage of low total harmonic distortion. Proposed is one algorithm for synchronization to the line voltage fully implemented in software. A novel line-voltage. disturbance detection scheme is developed and implemented in software. A 1kVA DSP-controlled laboratory prototype is built to verify the theoretically obtained results. A systematic design procedure and design example are presented and validated using a computer simulation.

Baronijan, Armen

1998-12-01

114

Stand-alone Open Source Software  

E-print Network

Information Systems Applications (LISA) ­ Test set of full profiles to assure concordance using AFDIL's ASAP) ­ 752 Powerplex 16 profiles (52 duplicates) · 0 Discordancies identified ­ 1 non-concordant sample samples contained in LISA · Duplicate profiles were generated at NIST using both Powerplex16

Levin, Judith G.

115

21 CFR 801.50 - Labeling requirements for stand-alone software.  

Code of Federal Regulations, 2014 CFR

...false Labeling requirements for stand-alone software. 801.50 Section 801.50 Food and Drugs...50 Labeling requirements for stand-alone software. (a) Stand-alone software that is not distributed in packaged...

2014-04-01

116

39 CFR 122.2 - Stand-alone special services.  

Code of Federal Regulations, 2012 CFR

...FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services...commissions, correction and ZIP Code placement of mailing lists, and address sequencing...For the domestic market-dominant mail products identified above in part 121,...

2012-07-01

117

39 CFR 122.2 - Stand-alone special services.  

Code of Federal Regulations, 2013 CFR

...FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services...commissions, correction and ZIP Code placement of mailing lists, and address sequencing...For the domestic market-dominant mail products identified above in part 121,...

2013-07-01

118

39 CFR 122.2 - Stand-alone special services.  

Code of Federal Regulations, 2010 CFR

...FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services...commissions, correction and ZIP Code placement of mailing lists, and address sequencing...For the domestic market-dominant mail products identified above in part 121,...

2010-07-01

119

39 CFR 122.2 - Stand-alone special services.  

Code of Federal Regulations, 2011 CFR

...FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services...commissions, correction and ZIP Code placement of mailing lists, and address sequencing...For the domestic market-dominant mail products identified above in part 121,...

2011-07-01

120

39 CFR 122.2 - Stand-alone special services.  

Code of Federal Regulations, 2014 CFR

...FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services...commissions, correction and ZIP Code placement of mailing lists, and address sequencing...For the domestic market-dominant mail products identified above in part 121,...

2014-07-01

121

Hanford tank initiative cone penetrometer stand alone grouting module  

SciTech Connect

The HTI subsurface characterization task will use the Hanford Cone Penetrometer platform (CPP) to deploy contaminant sensor and soil sampling probes into the vadose zone surrounding SST 241-AX-104. Closure of the resulting penetration holes may be stipulated by WAC requirements. A stand alone grouting capability deployable by the CPP has been developed. This qualification test plan defines testing of this capability to be performed at the Immobilized Low Activity Waste Disposal Complex.

CALLAWAY, W.S.

1998-10-15

122

45 CFR 156.150 - Application to stand-alone dental plans inside the Exchange.  

Code of Federal Regulations, 2014 CFR

... false Application to stand-alone dental plans inside the Exchange. 156.150...156.150 Application to stand-alone dental plans inside the Exchange. (a) Annual...cost-sharing. For a stand-alone dental plan covering the pediatric dental...

2014-10-01

123

45 CFR 156.150 - Application to stand-alone dental plans inside the Exchange.  

Code of Federal Regulations, 2013 CFR

... false Application to stand-alone dental plans inside the Exchange. 156.150...156.150 Application to stand-alone dental plans inside the Exchange. (a) Annual...on cost-sharing. A stand-alone dental plan covering the pediatric...

2013-10-01

124

49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.  

Code of Federal Regulations, 2011 CFR

... false Procedural schedule in stand-alone cost cases. 1111.8 Section 1111...1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule...procedural schedule will apply in stand-alone cost cases: Day 0—Complaint...

2011-10-01

125

49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.  

Code of Federal Regulations, 2010 CFR

... false Procedural schedule in stand-alone cost cases. 1111.8 Section 1111...1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule...procedural schedule will apply in stand-alone cost cases: Day 0—Complaint...

2010-10-01

126

University of Essex Rules of Assessment for stand-alone Postgraduate Certificates Page 1 of 4  

E-print Network

University of Essex Rules of Assessment for stand-alone Postgraduate Certificates Page 1 of 4 as a stand-alone award) 1 PREAMBLE a) These rules apply to full-time postgraduate certificate courses Rules of Assessment for stand-alone Postgraduate Certificates Page 2 of 4 3.1.1 Pass with Merit a

Codling, Edward A.

127

University of Essex Rules of Assessment for stand-alone Graduate Certificates Page 1 of 3  

E-print Network

University of Essex Rules of Assessment for stand-alone Graduate Certificates Page 1 of 3 as a stand-alone award) 1 PREAMBLE a) These rules should be read in conjunction with the relevant Programme;University of Essex Rules of Assessment for stand-alone Graduate Certificates Page 2 of 3 4.1 If a student

Codling, Edward A.

128

Deformation Mechanisms in Compression-Loaded, Stand-Alone Plasma-Sprayed Alumina Coatings  

E-print Network

Deformation Mechanisms in Compression-Loaded, Stand-Alone Plasma-Sprayed Alumina Coatings Rodney W, Northwestern University, Evanston, Illinois 60208 Cylindrical, stand-alone tubes of plasma-sprayed alumina were-resistant coatings with extended lifetimes. Previous research has investigated stand-alone plasma-sprayed coatings

Trice, Rodney W.

129

49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.  

Code of Federal Regulations, 2014 CFR

... false Procedural schedule in stand-alone cost cases. 1111.8 Section 1111...1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule...procedural schedule will apply in stand-alone cost cases: Day 0—Complaint...

2014-10-01

130

49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.  

Code of Federal Regulations, 2013 CFR

... false Procedural schedule in stand-alone cost cases. 1111.8 Section 1111...1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule...procedural schedule will apply in stand-alone cost cases: Day 0—Complaint...

2013-10-01

131

49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.  

Code of Federal Regulations, 2012 CFR

... false Procedural schedule in stand-alone cost cases. 1111.8 Section 1111...1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule...procedural schedule will apply in stand-alone cost cases: Day 0—Complaint...

2012-10-01

132

University of Essex Rules of Assessment for stand-alone Graduate Diplomas Page 1 of 4  

E-print Network

University of Essex Rules of Assessment for stand-alone Graduate Diplomas Page 1 of 4 UNIVERSITY OF ESSEX GRADUATE SCHOOL RULES OF ASSESSMENT FOR GRADUATE DIPLOMAS 2011/12 (where offered as a stand-alone Rules of Assessment for stand-alone Graduate Diplomas Page 2 of 4 3.1.1 Pass with Merit a) Dominant

Codling, Edward A.

133

Design Considerations for Stand-alone Haptic Interfaces Communicating via UDP Protocol  

E-print Network

Design Considerations for Stand-alone Haptic Interfaces Communicating via UDP Protocol Ryan M for high speed communication between a stand-alone haptic interface and a computer running haptic rendering, there has been much work in recent years toward developing stand-alone and plug-and-play haptic interfaces

Tan, Hong Z.

134

Design Considerations for Stand-alone Haptic Interfaces Communicating via UDP Protocol  

E-print Network

Design Considerations for Stand-alone Haptic Interfaces Communicating via UDP Protocol Ryan M was motivated by the need for high-speed communication between a stand-alone haptic interface and an external more mature, there has been much work in recent years toward developing stand-alone and plug

Tan, Hong Z.

135

Probabilistic modeling of solar power systems  

Microsoft Academic Search

The author presents a probabilistic approach based on Markov chain theory to model stand-alone photovoltaic power systems and predict their long-term service performance. The major advantage of this approach is that it allows designers and developers of these systems to analyze the system performance as well as the battery subsystem performance in the long run and determine the system design

Fayssal M. Safie

1989-01-01

136

Market assessment of photovoltaic power systems for agricultural applications in Nigeria  

NASA Technical Reports Server (NTRS)

The market potential for stand-alone photovoltaic systems in agriculture was studied. Information is presented on technical and economically feasible applications, and assessments of the business, government and financial climate for photovoltaic sales. It is concluded that the market for stand-alone systems will be large because of the availability of captial and the high premium placed on high reliability, low maintenance power systems. Various specific applications are described, mostly related to agriculture.

Staples, D.; Steingass, H.; Nolfi, J.

1981-01-01

137

Market assessment of photovoltaic power systems for agricultural applications in Nigeria  

NASA Astrophysics Data System (ADS)

The market potential for stand-alone photovoltaic systems in agriculture was studied. Information is presented on technical and economically feasible applications, and assessments of the business, government and financial climate for photovoltaic sales. It is concluded that the market for stand-alone systems will be large because of the availability of captial and the high premium placed on high reliability, low maintenance power systems. Various specific applications are described, mostly related to agriculture.

Staples, D.; Steingass, H.; Nolfi, J.

1981-10-01

138

A rule-based fuzzy logic controller for a PWM inverter in a stand alone wind energy conversion scheme  

Microsoft Academic Search

The paper presents a rule-based fuzzy logic controller to control the output power of a pulse width modulated (PWM) inverter used in a stand-alone wind energy conversion scheme (SAWECS). The self-excited induction generator used in SAWECS has the inherent problem of fluctuations in the magnitude and frequency of its terminal voltage with changes in wind velocity and load. To overcome

Rohin M. Hilloowala; Adel M. Sharaf

1996-01-01

139

Edinburgh Research Explorer A stand-alone solar adsorption refrigerator for humanitarian aid  

E-print Network

, versatile, solar driven ice maker operating with the activated carbon/methanol adsorption pair has beenEdinburgh Research Explorer A stand-alone solar adsorption refrigerator for humanitarian aid stand-alone solar adsorption refrigerator for humanitarian aid' Solar energy, vol 100, pp. 172-178., 10

Edinburgh, University of

140

University of Essex Rules of Assessment for stand-alone Postgraduate Diplomas Page 1 of 4  

E-print Network

University of Essex Rules of Assessment for stand-alone Postgraduate Diplomas Page 1 of 4 as a stand-alone award) 1 PREAMBLE a) These rules apply to full-time (9 months) postgraduate diploma courses alone diplomas may also be awarded with merit. d) It is for the Board of Examiners to determine whether

Codling, Edward A.

141

Stand alone induction generator with terminal impedance controller and no turbine controls  

Microsoft Academic Search

Induction generators with hydraulic turbines are often used for cogeneration. The same turbine generator configuration can be used for stand-alone generation if an impedance controller is connected to the generator terminals; this configuration requires no hydraulic controls on the turbine. The authors propose an electronic impedance controller to control the voltage and the frequency of a stand-alone induction generator. The

R. Bonert; G. Hoops

1990-01-01

142

A Task-Oriented Framework for Stand-Alone Technology Integration Classes  

ERIC Educational Resources Information Center

A long-standing challenge for schools of education is how to prepare teachers to effectively integrate technology into classroom instruction. A widespread practice in training preservice teachers is the stand-alone technology class. These classes have evolved over time. This article suggests a further development in stand-alone technology classes:…

Hammond, Thomas C.

2007-01-01

143

Study of Stand-Alone Microgrid under Condition of Faults on Distribution Line  

NASA Astrophysics Data System (ADS)

The behavior of stand-alone microgrid is analyzed under the condition of faults on distribution feeders. During fault since battery is not able to maintain dc-link voltage within limit, the resistive dump load control is presented to do so. An inverter control is proposed to maintain balanced voltages at PCC under the unbalanced load condition and to reduce voltage unbalance factor (VUF) at load points. The proposed inverter control also has facility to protect itself from high fault current. Existing maximum power point tracker (MPPT) algorithm is modified to limit the speed of generator during fault. Extensive simulation results using MATLAB/SIMULINK established that the performance of the controllers is quite satisfactory under different fault conditions as well as unbalanced load conditions.

Malla, S. G.; Bhende, C. N.

2014-10-01

144

Stand-alone microprocessor controlled fast sweep Langmuir probe driver  

Microsoft Academic Search

This article describes a power supply and data logger for a Langmuir probe interfaced to a personal computer. The system provides a voltage sweep range from ?125 to +100 V in 100 steps in a time ?0.15 s. Restricted sweep ranges and single point operation are also possible. Probe current measurements are in the range from ?1.0 to +100 mA

A. D. Cheetham; L. Davidson; J. Jakobsen; T. Lund; J. P. Rayner

1997-01-01

145

Stand-alone microprocessor controlled fast sweep Langmuir probe driver  

SciTech Connect

This article describes a power supply and data logger for a Langmuir probe interfaced to a personal computer. The system provides a voltage sweep range from {minus}125 to +100 V in 100 steps in a time {approximately}0.15 s. Restricted sweep ranges and single point operation are also possible. Probe current measurements are in the range from {minus}1.0 to +100 mA with a precision of 5 {mu}A on the most sensitive range, while the voltage may be set with a precision of 56 mV. Novel features of the system include: the use of integrate-and-dump techniques to implement the process of analog-to-digital conversion and to provide effective noise suppression; a solution to the problem of floating the power supply on top of the potential developed across the grounded current sensing resistor based on the power supply rejection ratio characteristics of a high voltage operational amplifier; and the development of an interface and control board employing the GPIB protocol to communicate with a host computer. Successful operation of the system has been demonstrated in the electrically noisy environment of a helicon plasma source. {copyright} {ital 1997 American Institute of Physics.}

Cheetham, A.D.; Davidson, L.; Jakobsen, J.; Lund, T.; Rayner, J.P. [Plasma Instrumentation Laboratory, University of Canberra, P.O. Box 1, Belconnen ACT 2616 (Australia)] [Plasma Instrumentation Laboratory, University of Canberra, P.O. Box 1, Belconnen ACT 2616 (Australia)

1997-09-01

146

The TIME: A Stand-Alone Measure of College Students' Test-Taking Attitudes.  

ERIC Educational Resources Information Center

Discusses the development of a stand-alone measure of college students' test-taking attitudes. Analysis of the TIME (Treatment Rejection, Infrequency, Minimizing, and Exaggeration) lends strong support to its validity, although more studies are needed. (MKA)

Kirklen, Leonard E.; Reed, James R.; Strozier, Anne L.; Cloak, Nancy L.

1998-01-01

147

Fundamental Frequency Modulated Multilevel Inverter for Three-Phase Stand-Alone  

E-print Network

technologies in PV utilization. Multilevel voltage source inverters offer several advantages comparedFundamental Frequency Modulated Multilevel Inverter for Three-Phase Stand-Alone Photovoltaic-6472, USA Abstract - This paper presents a fundamental frequency modulated multilevel inverter scheme

Tolbert, Leon M.

148

Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 2  

NASA Technical Reports Server (NTRS)

The Stand Alone Pressure Measurement Device (SAPMD) specifications are examined. The HP.SAPMD GSE software is listed; the HP/SGA readme program is presented; and the SPMD acceptance test procedure is described.

Tomlinson, Bill

1989-01-01

149

Casinos in context : the impacts of stand-alone casino development on urban neighborhoods  

E-print Network

As the stigma of gambling fades and governments seek more sources of revenue the urban casino is becoming more common. Many of these are legalized to operate with limited competition in their state, standing alone in their ...

Schray, Luke J. (Luke Joseph)

2007-01-01

150

49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.  

Code of Federal Regulations, 2010 CFR

...considered under the stand-alone cost methodology. 1109.4 Section 1109.4 Transportation...considered under the stand-alone cost methodology. (a) A shipper seeking rate relief...case involving the stand-alone cost methodology must engage in non-binding...

2010-10-01

151

49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.  

Code of Federal Regulations, 2011 CFR

...cases to be considered under the stand-alone cost methodology. 1109.4 Section...cases to be considered under the stand-alone cost methodology. (a) A shipper...railroads in a case involving the stand-alone cost methodology must engage in...

2011-10-01

152

49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.  

Code of Federal Regulations, 2012 CFR

...cases to be considered under the stand-alone cost methodology. 1109.4 Section...cases to be considered under the stand-alone cost methodology. (a) A shipper...railroads in a case involving the stand-alone cost methodology must engage in...

2012-10-01

153

49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.  

Code of Federal Regulations, 2014 CFR

...cases to be considered under the stand-alone cost methodology. 1109.4 Section...cases to be considered under the stand-alone cost methodology. (a) Mandatory use...railroads in a case involving the stand-alone cost methodology must engage in...

2014-10-01

154

49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.  

Code of Federal Regulations, 2013 CFR

...cases to be considered under the stand-alone cost methodology. 1109.4 Section...cases to be considered under the stand-alone cost methodology. (a) Mandatory use...railroads in a case involving the stand-alone cost methodology must engage in...

2013-10-01

155

Stand-Alone and Hybrid Positioning Using Asynchronous Pseudolites  

PubMed Central

global navigation satellite system (GNSS) receivers are usually unable to achieve satisfactory performance in difficult environments, such as open-pit mines, urban canyons and indoors. Pseudolites have the potential to extend GNSS usage and significantly improve receiver performance in such environments by providing additional navigation signals. This also applies to asynchronous pseudolite systems, where different pseudolites operate in an independent way. Asynchronous pseudolite systems require, however, dedicated strategies in order to properly integrate GNSS and pseudolite measurements. In this paper, several asynchronous pseudolite/GNSS integration strategies are considered: loosely- and tightly-coupled approaches are developed and combined with pseudolite proximity and receiver signal strength (RSS)-based positioning. The performance of the approaches proposed has been tested in different scenarios, including static and kinematic conditions. The tests performed demonstrate that the methods developed are effective techniques for integrating heterogeneous measurements from different sources, such as asynchronous pseudolites and GNSS. PMID:25609041

Gioia, Ciro; Borio, Daniele

2015-01-01

156

Stand-alone and hybrid positioning using asynchronous pseudolites.  

PubMed

global navigation satellite system (GNSS) receivers are usually unable to achieve satisfactory performance in difficult environments, such as open-pit mines, urban canyons and indoors. Pseudolites have the potential to extend GNSS usage and significantly improve receiver performance in such environments by providing additional navigation signals. This also applies to asynchronous pseudolite systems, where different pseudolites operate in an independent way. Asynchronous pseudolite systems require, however, dedicated strategies in order to properly integrate GNSS and pseudolite measurements. In this paper, several asynchronous pseudolite/GNSS integration strategies are considered: loosely- and tightly-coupled approaches are developed and combined with pseudolite proximity and receiver signal strength (RSS)-based positioning. The performance of the approaches proposed has been tested in different scenarios, including static and kinematic conditions. The tests performed demonstrate that the methods developed are effective techniques for integrating heterogeneous measurements from different sources, such as asynchronous pseudolites and GNSS. PMID:25609041

Gioia, Ciro; Borio, Daniele

2015-01-01

157

An intelligent stand-alone ultrasonic device for monitoring local structural damage: implementation and preliminary experiments  

NASA Astrophysics Data System (ADS)

Continuous structural health monitoring has the potential to significantly improve the safety management of aged, in-service civil structures. In particular, monitoring of local damage growth at hot-spot areas can help to prevent disastrous structural failures. Although ultrasonic nondestructive evaluation (NDE) has proved to be effective in monitoring local damage growth, conventional equipment and devices are usually bulky and only suitable for scheduled human inspections. The objective of this research is to harness the latest developments in embedded hardware and wireless communication for developing a stand-alone, compact ultrasonic device. The device is directed at the continuous structural health monitoring of civil structures. Relying on battery power, the device possesses the functionalities of high-speed actuation, sensing, signal processing, and wireless communication. Integrated with contact ultrasonic transducers, the device can generate 1 MHz Rayleigh surface waves in a steel specimen and measure response waves. An envelope detection algorithm based on the Hilbert transform is presented for efficiently determining the peak values of the response signals, from which small surface cracks are successfully identified.

Pertsch, Alexander; Kim, Jin-Yeon; Wang, Yang; Jacobs, Laurence J.

2011-01-01

158

High-responsivity thermoelectric infrared detectors with stand-alone sub-micrometer polysilicon wires  

NASA Astrophysics Data System (ADS)

A novel high-responsivity uncooled thermoelectric (TE) infrared (IR) detector is designed, fabricated and characterized. This detector features a single stand-alone polysilicon-based thermocouple (without a supporting membrane) covered by an umbrella-like optical cavity IR absorber. It is proved that the highest responsivity in the developed detectors can be achieved with only one thermocouple. Using a single thermocouple also results in a low resistance detector, which consequently limits the Johnson noise (e.g. less than 30?nv/?Hz in this work). Since the sub-micrometer polysilicon TE wires are the only heat path from the hot junction to the substrate, a superior thermal isolation is achieved. A responsivity of 1800?V?W?1 and a detectivity of 2* 108 (cm?Hz1/2 W?1) are measured from a 20? × ?20?µm detector comparable to the performance of detectors used in commercial focal planar arrays [1]. This performance in a compact and manufacturable design elevates the position of thermoelectric IR sensors as a candidate for low-power, high performance and inexpensive focal planar arrays.

Modarres-Zadeh, Mohammad J.; Abdolvand, Reza

2014-12-01

159

Array structure design handbook for stand alone photovoltaic applications  

NASA Technical Reports Server (NTRS)

This handbook will permit the user to design a low-cost structure for a variety of photovoltaic system applications under 10 kW. Any presently commercially available photovoltaic modules may be used. Design alternatives are provided for different generic structure types, structural materials, and electric interfaces. The use of a hand-held calculator is sufficient to perform the necessary calculations for the array designs.

Didelot, R. C.

1980-01-01

160

Comparison of stand-alone polyetheretherketone cages and iliac crest autografts for the treatment of cervical degenerative disc diseases  

Microsoft Academic Search

Background  Anterior cervical decompression and fusion (ACDF) is a widely accepted surgical procedure for the treatment of cervical degenerative\\u000a disc diseases. This retrospective study was designed to analyze and compare the efficacy and outcomes of anterior cervical\\u000a fusion using stand-alone polyetheretherketone (PEEK) cages and autogenous iliac crest grafts with the anterior cervical plating\\u000a system.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A total of 72 consecutive patients suffering

Jian Zhou; Qing Xia; Jian Dong; Xilei Li; Xiaogang Zhou; Taolin Fang; Hong Lin

2011-01-01

161

A Layerwise Shell Stiffener and Stand-Alone Curved Beam Element  

E-print Network

1 A Layerwise Shell Stiffener and Stand-Alone Curved Beam Element SAMUEL KINDE KASSEGNE* and J. N-dimensional stiffener element for laminated composite shells and plates is developed based on the Layerwise Theory of Reddy for composite laminates. The element has a displacement field compatible with that of a layerwise

Kassegne, Samuel Kinde

162

EVALUATION AND USE OF STAND-ALONE COMMERCIAL PHOTOLYTIC CONVERTERS FOR NO2 TO NO CONVERSION  

EPA Science Inventory

Two types of stand-alone commercial photolytic converters of NO2 to NO are now available for use with NO, O3 chemiluminescence monitors for the measurement of NO2. Both units have been tested for interferences resulting from photolysis of HONO or from decomposition of PAN. On...

163

Integrating a Redox Flow Battery System with a Wind-Diesel Power System  

Microsoft Academic Search

Energy storage devices are required for power quality maintenance in stand alone power systems like wind-diesel ones. A redox flow battery system has many virtues which make its integration with a wind-diesel power system attractive. This paper proposes the integration of a redox flow battery system with a typical multi-machine wind-diesel power system for simultaneous voltage and frequency regulation. The

S. A. Lone; M.-u-D. Mufti

2006-01-01

164

Stand-alone calculation tools are not the answer to embodied carbon assessment  

E-print Network

at the early stages of a design. An alternative to these stand-alone tools is offered through the functionality of Building Information Modelling (BIM) software, which is capable of incorporating embodied carbon assessments as part of the normal design... . Keywords: Embodied carbon; buildings; greenhouse gases; carbon dioxide; envionmental impact assessment Nomenclature LCA Life Cycle Assessment BIM Building Information Modelling 3D 3 Dimensional * Corresponding author. Tel.: +44 7905148580; fax...

Ariyaratne, Chamindika I.; Moncaster, Alice M.

2014-12-26

165

Control and analysis of a hybrid renewable energy-based power system  

Microsoft Academic Search

This paper proposes a methodology for the integration of various energy sources into a hybrid generation system for stand-alone power applications. The system employs a wind generator (WG) and photovoltaic (PV) arrays as main energy sources while a fuel cell (FC) is included for supplying excess power demand. An ultra-capacitor (UC) bank is also implemented in order to cover rapid

C. Patsios; M. Antonakopoulos; A. Chaniotis; A. Kladas

2010-01-01

166

SADIST (the SAndia Data Index STructure): a stand-alone data base for computer-aided design and general use  

SciTech Connect

A file structure has been designed that fills the needs of multilevel hierarchical design of integrated circuits (ICs). Since the structure is actualized by a stand-alone FORTRAN program, it is applicable to general-purpose use in situations where the structure of the data modeled is similar to that of IC data. Though the structure itself is a FORTRAN direct-access file, its interface with user programs is a small sequential subfile accessible to FORTRAN, PASCAL, and most other languages. This ability facilitates linkup to systems already in use and requires minimal recoding. Backup, restore, and other data base recovery and integrity operations are automatic, but may be initiated by the user if desired. 3 figures.

Stauffer, J D

1980-11-01

167

Quick and reliable technology for fabrication of stand-alone BSCCO mesas  

NASA Astrophysics Data System (ADS)

The technology of wet etching allowing fabrication of stand-alone BSCCO mesa structures was proposed. The produced mesas can be made much thicker than ones usually being studied. The time required for the fabrication is much smaller in comparison with the standard method of ion milling. The process used is controllable which provides acceptable precision of mesa fabrication. The IV characteristics of the sample showing Josephson nature were obtained. The qualitative comparison with characteristics of similar structures fabricated by other groups was carried out.

Vopilkin, E. A.; Chiginev, A. V.; Revin, L. S.; Tropanova, A. N.; Shuleshova, I. Yu; Okhapkin, A. I.; Shovkun, A. D.; Kulakov, A. B.; Pankratov, A. L.

2015-04-01

168

77 FR 14006 - Proposed Development of the Alaska Stand Alone Gas Pipeline Project (ASAP), From the North Slope...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Proposed Development of the Alaska Stand Alone Gas Pipeline Project (ASAP), From the North Slope to South Central Alaska, Draft Environmental Impact...1, 2012. William Keller, North Branch Chief, Alaska...

2012-03-08

169

Design Considerations for StandDesign Considerations for Stand--alone Haptic Interfacesalone Haptic Interfaces Communicating via UDP ProtocolCommunicating via UDP Protocol  

E-print Network

Design Considerations for StandDesign Considerations for Stand--alone Haptic Interfacesalone Haptic discussed in the paper "Design Considerations for StandDesign Considerations for Stand--alone Haptic-speed communication between a stand-alone haptic interface and an external computer running haptic rendering

Tan, Hong Z.

170

Photoinduced Postsynthetic Polymerization of a Metal-Organic Framework toward a Flexible Stand-Alone Membrane.  

PubMed

Metal-organic frameworks (MOFs) are a promising class of nanoporous polymeric materials. However, the processing of such fragile crystalline powders into desired shapes for further applications is often difficult. A photoinduced postsynthetic polymerization (PSP) strategy was now employed to covalently link MOF crystals by flexible polymer chains, thus endowing the MOF powders with processability and flexibility. Nanosized UiO-66-NH2 was first functionalized with polymerizable functional groups, and its subsequent copolymerization with monomers was easily induced by UV light under solvent-free and mild conditions. Because of the improved interaction between MOF particles and polymer chains, the resulting stand-alone and elastic MOF-based PSP-derived membranes possess crack-free and uniform structures and outstanding separation capabilities for Cr(VI) ions from water. PMID:25736697

Zhang, Yuanyuan; Feng, Xiao; Li, Haiwei; Chen, Yifa; Zhao, Jingshu; Wang, Shan; Wang, Lu; Wang, Bo

2015-03-27

171

Biomechanical comparison of three stand-alone lumbar cages — a three-dimensional finite element analysis  

PubMed Central

Background For anterior lumbar interbody fusion (ALIF), stand-alone cages can be supplemented with vertebral plate, locking screws, or threaded cylinder to avoid the use of posterior fixation. Intuitively, the plate, screw, and cylinder aim to be embedded into the vertebral bodies to effectively immobilize the cage itself. The kinematic and mechanical effects of these integrated components on the lumbar construct have not been extensively studied. A nonlinearly lumbar finite-element model was developed and validated to investigate the biomechanical differences between three stand-alone (Latero, SynFix, and Stabilis) and SynCage-Open plus transpedicular fixation. All four cages were instrumented at the L3-4 level. Methods The lumbar models were subjected to the follower load along the lumbar column and the moment at the lumbar top to produce flexion (FL), extension (EX), left/right lateral bending (LLB, RLB), and left/right axial rotation (LAR, RAR). A 10 Nm moment was applied to obtain the six physiological motions in all models. The comparison indices included disc range of motion (ROM), facet contact force, and stresses of the annulus and implants. Results At the surgical level, the SynCage-open model supplemented with transpedicular fixation decreased ROM (>76%) greatly; while the SynFix model decreased ROM 56-72%, the Latero model decreased ROM 36-91%, in all motions as compared with the INT model. However, the Stabilis model decreased ROM slightly in extension (11%), lateral bending (21%), and axial rotation (34%). At the adjacent levels, there were no obvious differences in ROM and annulus stress among all instrumented models. Conclusions ALIF instrumentation with the Latero or SynFix cage provides an acceptable stability for clinical use without the requirement of additional posterior fixation. However, the Stabilis cage is not favored in extension and lateral bending because of insufficient stabilization. PMID:24088294

2013-01-01

172

Power Systems Integration Laboratory (Fact Sheet)  

SciTech Connect

This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Power Systems Integration Laboratory at the Energy Systems Integration Facility. At NREL's Power Systems Integration Laboratory in the Energy Systems Integration Facility (ESIF), research focuses on developing and testing large-scale distributed energy systems for grid-connected, stand-alone, and microgrid applications. The laboratory can accommodate large power system components such as inverters for photovoltaic (PV) and wind systems, diesel and natural gas generators, battery packs, microgrid interconnection switchgear, and vehicles. Closely coupled with the research electrical distribution bus at the ESIF, the Power Systems Integration Laboratory will offer power testing capability of megawatt-scale DC and AC power systems, as well as advanced hardware-in-the-loop and model-in-the-loop simulation capabilities. Thermal heating and cooling loops and fuel also allow testing of combined heating/cooling and power systems (CHP).

Not Available

2011-10-01

173

Metabolomic analysis via reversed-phase ion-pairing liquid chromatography coupled to a stand alone orbitrap mass spectrometer  

PubMed Central

We present a liquid chromatography-mass spectrometry (LC-MS) method that capitalizes on the mass-resolving power of the orbitrap to enable sensitive and specific measurement of known and unanticipated metabolites in parallel, with a focus on water soluble species involved in core metabolism. The reversed phase LC method, with a cycle time 25 min, involves a water-methanol gradient on a C18 column with tributylamine as the ion pairing agent. The MS portion involves full scans from 85 – 800 m/z at 1 Hz and 100,000 resolution in negative ion mode on a stand alone orbitrap (“Exactive”). The median limit of detection, across 80 metabolite standards, was 5 ng/mL with linear range typically ? 100-fold. For both standards and a cellular extract from Saccharomyces cerevisiae (Baker’s yeast), the median inter-run relative standard deviation in peak intensity was 8%. In yeast exact, we detected 137 known compounds, whose 13C-labeling patterns could also be tracked to probe metabolic flux. In yeast engineered to lack a gene of unknown function (YKL215C), we observed accumulation of an ion of m/z 128.0351, which we subsequently confirmed to be oxoproline, resulting in annotation of YKL215C as an oxoprolinase. These examples demonstrate the suitability of the present method for quantitative metabolomics, fluxomics, and discovery metabolite profiling. PMID:20349993

Lu, Wenyun; Clasquin, Michelle F.; Melamud, Eugene; Amador-Noguez, Daniel; Caudy, Amy A.; Rabinowitz, Joshua D.

2010-01-01

174

Utilizing the heat content of gas-to-liquids by-product streams for commercial power generation  

E-print Network

plant thermal efficiency. A detailed economic analysis on the LNG, stand-alone GTL, and Integrated GTL Power-Generation plants indicates that the integrated system is more profitable than the other options considered. Justifying...

Adegoke, Adesola Ayodeji

2006-10-30

175

Serial endovascular embolization as stand-alone treatment of a sacral aneurysmal bone cyst.  

PubMed

Aneurysmal bone cysts (ABCs) are destructive cystic lesions of the bone and are common in children. They are expansile in nature and, therefore, may become symptomatic. These have traditionally been treated surgically; but recently, endovascular embolization has shown promise as a stand-alone therapy. The authors describe a case of an ABC highlighting the effectiveness and efficiency of endovascular treatment. A 16-year-old boy was referred for a 4-month history of radiating back pain and urinary hesitancy. Findings from his neurological examination were normal, but he had problems ambulating because of pain. Magnetic resonance imaging and CT scanning showed a cystic mass in the sacrum; a biopsy was performed and diagnosis of ABC was confirmed. Treatment options were then discussed with the family. The patient underwent 2 endovascular embolizations in approximately 1 month: Onyx 18 was involved in the first session, and N-butyl cyanoacrylate glue was used in the second session. After the first treatment, the patient experienced a dramatic decrease in pain and concomitant improvement in function. The patient went from being mildly symptomatic after the first treatment to completely asymptomatic after the second treatment. Clinical and radiographic follow-up obtained at 2, 6, and 18 months after initial treatment revealed the patient to be asymptomatic with progressive ossification. Endovascular treatment can be effective in treating symptomatic cases of ABC in which surgery would carry significant risk. Selective arterial embolization can promote sclerosis and result in an immediate and significant decrease in pain. PMID:24328760

Doss, Vinodh T; Weaver, Jason; Didier, Scott; Arthur, Adam S

2014-02-01

176

SAPT units turn-on in an interference-dominant environment. [Stand Alone Pressure Transducer  

NASA Technical Reports Server (NTRS)

A stand alone pressure transducer (SAPT) is a credit-card-sized smart pressure sensor inserted between the tile and the aluminum skin of a space shuttle. Reliably initiating the SAPT units via RF signals in a prelaunch environment is a challenging problem. Multiple-source interference may exist if more than one GSE (ground support equipment) antenna is turned on at the same time to meet the simultaneity requirement of 10 ms. A polygon model for orbiter, external tank, solid rocket booster, and tail service masts is used to simulate the prelaunch environment. Geometric optics is then applied to identify the coverage areas and the areas which are vulnerable to multipath and/or multiple-source interference. Simulation results show that the underside areas of an orbiter have incidence angles exceeding 80 deg. For multipath interference, both sides of the cargo bay areas are found to be vulnerable to a worst-case multipath loss exceeding 20 dB. Multiple-source interference areas are also identified. Mitigation methods for the coverage and interference problem are described. It is shown that multiple-source interference can be eliminated (or controlled) using the time-division-multiplexing method or the time-stamp approach.

Peng, W.-C.; Yang, C.-C.; Lichtenberg, C.

1990-01-01

177

On the storage batteries used in solar electric power systems and development of an algorithm for determining their ampere–hour capacity  

Microsoft Academic Search

Storage batteries are indispensable in all stand alone solar electric systems (PV power systems). Their efficiencies and life times affect significantly the overall PV system performance and economics. Batteries specified especially for use in PV systems have to be distinguished with standing of very deep discharge rate and high cycling stability.Ordinary batteries being marketed world wide for use in automobile,

Marwan M. Mahmoud

2004-01-01

178

Vector controlled induction machines for stand-alone wind energy applications  

Microsoft Academic Search

This paper describes the system and control structures for vector controlled induction generators used for variable speed, wind energy conversion (WEC) systems. The paper focuses on WEC systems feeding an isolated load or weak grid since for such systems the generated voltage and power flow must be regulated by the WEC system itself and the control structures are not trivial.

R. S. Pena; R. J. Cardenas; G. M. Asher; J. C. Clare

2000-01-01

179

Improving Indoor Air Quality in Hospital Environments and Dental Practices with Modular Stand-Alone Air Cleaning Devices  

Microsoft Academic Search

The goal of this study was to investigate the effectiveness of stand-alone modular air purification sys- tems in improving air quality in dental practices, hospital and laboratory environments. As air pollu- tant make-up and concentration may vary significantly in different indoor environments, the air clean- ing technologies utilised should be optimised for the pollutants targeted in a particular environment. Reduction

L. Erdinger; P. Rezvani; F. Hammes; H.-G. Sonntag

180

Water Wisdom: 23 Stand-Alone Activities on Water Supply and Water Conservation for High School Students. 2nd Edition.  

ERIC Educational Resources Information Center

This water conservation education program for high schools consists of both stand-alone activities and teacher support materials. Lessons are divided into six broad categories: (1) The Water Cycle; (2) Water and Society; (3) Keeping Water Pure; (4) Visualizing Volumes; (5) The Economics of Water Use; and (6) Domestic Water Conservation. The…

Massachusetts State Water Resources Authority, Boston.

181

EVALUATION AND USE OF STAND-ALONE COMMERCIAL PHOTOLYTIC CONVERTERS FOR CONVERSION OF NO2 AND NO  

EPA Science Inventory

Two types of stand-alone photolytic converters of nitrogen dioxide (NO2) to nitric oxide (NO) are now commercially available for use with NO, ozone (O3) chemiluminescence detector (CLD) monitors for the measurement of NO2. Both units have been tested for interferences resulting...

182

Review of stand-alone photovoltaic application projects sponsored by US DOE and US AID  

NASA Astrophysics Data System (ADS)

Experience with dc photovoltaic systems (without backup power) and ranging in output from 23 to 3,500 peak watts, in a wide range of environmental conditions and with a wide range of insolation, is described. Cooperation of NASA with other government agencies resulted in the installation of an air pollution monitor in New Jersey, a seismic sensor in Hawaii, power for lookout towers in national forests in California, an electric power system for a Papago Indian village in Arizona, and a power system for a grain mill and water pump in Tangaye, Upper Volta. Significant operational results are discussed and system reliability is assessed for the 20 experimental systems installed since 1976. Additional systems to be installed overseas are highlighted, and economic factors are considered.

Bifano, W. J.

183

Review of stand-alone photovoltaic application projects sponsored by US DOE and US AID  

NASA Technical Reports Server (NTRS)

Experience with dc photovoltaic systems (without backup power) and ranging in output from 23 to 3,500 peak watts, in a wide range of environmental conditions and with a wide range of insolation, is described. Cooperation of NASA with other government agencies resulted in the installation of an air pollution monitor in New Jersey, a seismic sensor in Hawaii, power for lookout towers in national forests in California, an electric power system for a Papago Indian village in Arizona, and a power system for a grain mill and water pump in Tangaye, Upper Volta. Significant operational results are discussed and system reliability is assessed for the 20 experimental systems installed since 1976. Additional systems to be installed overseas are highlighted, and economic factors are considered.

Bifano, W. J.

1981-01-01

184

Multiloop control of Z-source inverter for single-phase power conditioning systems  

Microsoft Academic Search

This paper presents a Z-source inverter as a power conditioning system, which has bucking and boosting feature, for a single-phase stand-alone AC system. The bucking as well as boosting feature is possible because of additional shoot through state introduced in zero state of the conventional inverter pulse width modulation. A small DG system requires power conditioning units with low cost,

Thelukuntla Chandra Shekar; Mummadi Veerachary

2009-01-01

185

A mobile renewable house using PV\\/wind\\/fuel cell hybrid power system  

Microsoft Academic Search

A photovoltaic\\/wind\\/fuel cell hybrid power system for stand-alone applications is proposed and demonstrated with a mobile house. This concept shows that different renewable sources can be used simultaneously to power off-grid applications. The presented mobile house can produce sufficient power to cover the peak load. Photovoltaic and wind energy are used as primary sources and a fuel cell as backup

Mehmed Eroglu; Erkan Dursun; Suat Sevencan; Junseok Song; Suha Yazici; Osman Kilic

2011-01-01

186

Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications  

DOEpatents

An illumination source comprising a porous silicon having a source of electrons on the surface and/or interticies thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon.

Tam, Shiu-Wing (Downers Grove, IL)

1998-01-01

187

Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications  

DOEpatents

An illumination source comprising a porous silicon having a source of electrons on the surface and/or interticies thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon.

Tam, Shiu-Wing (Downers Grove, IL)

1997-01-01

188

Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications  

DOEpatents

An illumination source is disclosed comprising a porous silicon having a source of electrons on the surface and/or interstices thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon. 1 fig.

Tam, S.W.

1998-06-16

189

Porous silicon with embedded tritium as a stand-alone prime power source for optoelectronic applications  

DOEpatents

Disclosed is an illumination source comprising a porous silicon having a source of electrons on the surface and/or interstices thereof having a total porosity in the range of from about 50 v/o to about 90 v/o. Also disclosed are a tritiated porous silicon and a photovoltaic device and an illumination source of tritiated porous silicon. 1 fig.

Tam, S.W.

1997-02-25

190

A simple mathematical description of an off-grid hybrid solar-wind power generating system  

NASA Astrophysics Data System (ADS)

We give a detailed description of the energy balance equation for a stand-alone hybrid solar-wind power generating system. The dimensions of the power generator and the energy capacity of a buffer battery (used as an energy storage system) are chosen to suit a known consumer's profile. Future applications of the mathematical model developed and analogies with a similar hydrodynamic problem are discussed.

Blasone, M.; Dell'Anno, F.; De Luca, R.; Torre, G.

2013-05-01

191

Stress-Relaxation and Creep Behavior of Heat-Treated Stand-Alone Plasma-Sprayed 7 wt.% Y2O3-ZrO2 Coatings  

E-print Network

Stress-Relaxation and Creep Behavior of Heat-Treated Stand-Alone Plasma- Sprayed 7 wt.% Y2O3-ZrO2 Lafayette, Indiana, USA Abstract Plasma-sprayed 7 wt.% Y2O3-ZrO2 (YSZ) stand-alone coatings were subjected

Trice, Rodney W.

192

Peer-produced systems can achieve what might be infeasible for stand-alone systems developed  

E-print Network

and a cab dispatch back-end automatically requests from commuters with cell-phone cameras images of flooded of information. Coordinated effectively, the sum of the compositions yields something of far greater value than transformers; and applications. 8 1070-986X/07/$25.00 © 2007 IEEE Published by the IEEE Computer Society Media

Zhao, Feng

193

Energy storage considerations for a stand-alone wave energy plant  

Microsoft Academic Search

Despite several wave energy plants based on oscillating water column concept having been tested worldwide, wave energy has not yet gained popularity as a renewable energy source because of highly intermittent nature of available wave power. Still maintaining a constant voltage and frequency at the output, requires embedding of energy storage devices of sufficient capacity into the system. As the

S. Muthukumar; S. Kakumanu; S. Sriram; V. Jayashankar

2005-01-01

194

Design and fabrication of a photovoltaic power system for the Papago Indian village of Schuchuli (Gunsight), Arizona  

NASA Technical Reports Server (NTRS)

A stand alone photovoltaic power system for installation in the Papago Indian village of Schuchuli is being designed and fabricated to provide electricity for village water pumping and basic domestic needs. The system will consist of a 3.5 kW (peak) photovoltaic array; controls, instrumentations, and storage batteries located in an electrical equipment building and a 120 volt dc village distribution network. The system will power a 2 HP dc electric motor.

Bifano, W. J.; Ratajczak, A. F.; Ice, W. J.

1978-01-01

195

Hybrid solar\\/wind power system probabilistic modelling for long-term performance assessment  

Microsoft Academic Search

This paper presents a probabilistic approach based on the convolution technique to assess the long-term performance of a hybrid solar–wind power system (HSWPS) for both stand-alone and grid-linked applications. To estimate energy performance of HSWPS the reliability analysis is performed by the use of the energy index of reliability (EIR) directly related to energy expected not supplied (EENS). Analytical expressions

G. Tina; S. Gagliano; S. Raiti

2006-01-01

196

Performance of a stand-alone wind-electric ice maker for remote villages  

SciTech Connect

Two ice makers in the 1.1 metric tons per 24 hours (1.2 tons per day) size range were tested to determine their performance when directly coupled to a variable-frequency wind turbine generator. Initial tests were conducted using a dynamometer to simulate to wind to evaluate whether previously determined potential problems were significant and to define basic performance parameters. Field testing in Norman, Oklahoma, was completed to determine the performance of one of the ice makers under real wind conditions. As expected, the ice makers produced more ice at a higher speed than rated, and less ice at a lower speed. Due to the large start-up torque requirement of reciprocating compressors, the ice making system experienced a large start-up current and corresponding voltage drop which required a larger wind turbine that expected to provide the necessary current and voltage. Performance curves for ice production and power consumption are presented. A spreadsheet model was constructed to predict ice production at a user-defined site given the wind conditions for that location. Future work should include long-term performance tests and research on reducing the large start-up currents the system experiences when first coming on line.

Davis, H.C. [National Renewable Energy Lab., Golden, CO (United States); Brandemuehl, M.J. [University of Colorado, Boulder, CO (United States). Joint Center for Energy Management; Bergey, M.L.S. [Bergey Windpower Co., Norman, OK (United States)

1995-01-01

197

Stress Relaxation of Compression Loaded Plasma-Sprayed 7 Wt% Y2O3ZrO2 Stand-Alone Coatings  

E-print Network

Stress Relaxation of Compression Loaded Plasma-Sprayed 7 Wt% Y2O3­ZrO2 Stand-Alone Coatings Graeme, Purdue University, West Lafayette, Indiana 47907 Stand-alone plasma-sprayed tubes of 7 wt% Y2O3­ZrO2 made with a composition of 7 wt% Y2O3­93 wt% ZrO2 (YSZ). Plasma-sprayed coatings of YSZ have a layered lamel- lar

Trice, Rodney W.

198

Six-phase induction machine operating as a stand-alone self-excited induction generator  

E-print Network

generators are particularly used in small and isolated power plants based on wind turbine or hydroelectric of multiphase induction machines in renewable energy applications such as wind and hydropower. Thus, some exploitation conditions as in wind and hydro energy conversion. The main criteria are simple and rigid

Brest, Université de

199

Microstructure of high c-axis oriented stand-alone ZnO self-assembled film.  

PubMed

Stand-alone ZnO films were fabricated at air-liquid interfaces. The Microstructures of the films were observed precisely using a transmission electron microscope (TEM) in this study. They were assemblies of nano-sheets having uniform film thickness. The nano-sheets grew down toward the bottom of solutions by the supply of Zn ions from the solutions. X-ray diffraction patterns indicated high c-axis orientation of the films perpendicular to the air-liquid interface. An area of the nano-sheets was magnified for further observation. Electron diffraction patterns and lattice images indicated that the nano-sheets consisted of ZnO crystals. A slight amount of co-precipitated zinc carbonate hydroxide (Zn5(CO3)2(OH)6) was also observed. Their morphologies were drastically changed by electron beam irradiation because of dehydration and crystallization to ZnO. PMID:19441339

Masuda, Yoshitake; Kato, Kazumi

2009-01-01

200

Ultra-Compact Power Conversion Based on a CMOS-Compatible Microfabricated Power Inductor with Minimized Core Losses  

E-print Network

generation, with a higher-voltage distribution bus; and, a shift from larger, system-capable power supplies heads, integrated air-core inductor technology for RF systems, and stand-alone power inductor electronic systems, has resisted full integration primarily due to the difficulty of integrating inductors on

201

Optimal Variable Structure Self Regulating PSO-Controller for Stand-Alone Wave Energy Conversion Scheme  

Microsoft Academic Search

The paper presents a novel stabilization controller scheme system for a Wave Energy Converter (WEC). The proposed controller of WEC-Battery renewable energy system is based on Multi Objective Particle Swarm Optimization MOPSO technique. The optimization algorithm is implemented to control a novel low cost dynamic AC side filter\\/capacitor compensation scheme. The novel Dynamic Modulated Filter Capacitor Compensation scheme (MPFC) serves

Adel M. Sharaf; Adel A. A. El-Gammal

2010-01-01

202

Maximum power throughput in the multiphase BLDC generator  

Microsoft Academic Search

This paper presents an advanced control technique for maximum power throughput of the multiphase Brushless DC (BLDC) generator of given design. In a generator of given rating, the weight and size of the system affect the fuel consumption directly. Therefore, maximum power density is one of the most important issues in a stand-alone generator. BLDC generator has high power density

H.-W. Lee; T. Kim; M. Ehsani

2004-01-01

203

Power conditioning: The link between solar conversion and consumer  

Microsoft Academic Search

The power conditioning for two forms of renewable energy, wind and photovoltaics (PV) links electric power generation to the consumer with requirements that provide the main control inputs for the power flow. In addition to the coupling of PV and wind energy plants to existing grids, stand-alone systems are described. The latter offer early potential for market introduction of renewable

S. Heier; W. Kleinkauf; J. Sachau

1994-01-01

204

Control strategies for enhanced power smoothing in wind energy systems using a flywheel driven by a vector-controlled induction machine  

Microsoft Academic Search

This paper presents a novel control strategy for power smoothing in wind energy applications, especially those feeding a stand-alone load. The system is based on a vector-controlled induction machine driving a flywheel and addresses the problem of regulating the DC-link system voltage against both input power surges\\/sags from a wind turbine or sudden changes in load demand. The control is

Roberto Cárdenas; Rubén Peña; Greg Asher; Jon Clare

2001-01-01

205

Alignment of the CMS silicon strip tracker during stand-alone commissioning  

Microsoft Academic Search

The results of the CMS tracker alignment analysis are presented using the data from cosmic tracks, optical survey information, and the laser alignment system at the Tracker Integration Facility at CERN. During several months of operation in the spring and summer of 2007, about five million cosmic track events were collected with a partially active CMS Tracker. This allowed us

W. Adam; T. Bergauer; M. Dragicevic; M. Friedl; R. Frühwirth; S. Hänsel; J. Hrubec; M. Krammer; M. Oberegger; M. Pernicka; S. Schmid; R. Stark; H. Steininger; D. Uhl; W. Waltenberger; E. Widl; P. Van Mechelen; M. Cardaci; W. Beaumont; E. de Langhe; E. A. de Wolf; E. Delmeire; M. Hashemi; O. Bouhali; O. Charaf; B. Clerbaux; J.-P. Dewulf; S. Elgammal; G. Hammad; G. de Lentdecker; P. Marage; C. Vander Velde; P. Vanlaer; J. Wickens; V. Adler; O. Devroede; S. DeWeirdt; J. D'Hondt; R. Goorens; J. Heyninck; J. Maes; Matthias Ulrich Mozer; S. Tavernier; L. Van Lancker; P. Van Mulders; I. Villella; C. Wastiels; J.-L. Bonnet; G. Bruno; B. DeCallatay; B. Florins; A. Giammanco; G. Gregoire; Th Keutgen; D. Kcira; V. Lemaitre; D. Michotte; O. Militaru; K. Piotrzkowski; L. Quertermont; V. Roberfroid; X. Rouby; D. Teyssier; E. Daubie; E. Anttila; S. Czellar; P. Engström; J. Härkönen; V. Karimäki; J. Kostesmaa; A. Kuronen; T. Lampén; T. Lindén; P.-R. Luukka; T. Mäenää; S. Michal; E. Tuominen; J. Tuominiemi; M. Ageron; G. Baulieu; A. Bonnevaux; G. Boudoul; E. Chabanat; E. Chabert; R. Chierici; D. Contardo; R. Della Negra; T. Dupasquier; G. Gelin; N. Giraud; G. Guillot; N. Estre; R. Haroutunian; N. Lumb; S. Perries; F. Schirra; B. Trocme; S. Vanzetto; J.-L. Agram; R. Blaes; F. Drouhin; J.-P. Ernenwein; J.-C. Fontaine; J.-D. Berst; J.-M. Brom; F. Didierjean; U. Goerlach; P. Graehling; L. Gross; J. Hosselet; P. Juillot; A. Lounis; C. Maazouzi; C. Olivetto; R. Strub; P. Van Hove; G. Anagnostou; R. Brauer; H. Esser; L. Feld; W. Karpinski; K. Klein; C. Kukulies; J. Olzem; A. Ostapchuk; D. Pandoulas; G. Pierschel; F. Raupach; S. Schael; G. Schwering; D. Sprenger; M. Thomas; M. Weber; B. Wittmer; M. Wlochal; F. Beissel; E. Bock; G. Flugge; C. Gillissen; T. Hermanns; D. Heydhausen; D. Jahn; G. Kaussen; A. Linn; L. Perchalla; M. Poettgens; O. Pooth; A. Stahl; M. H. Zoeller; P. Buhmann; E. Butz; G. Flucke; R. Hamdorf; J. Hauk; R. Klanner; U. Pein; P. Schleper; G. Steinbrück; P. Blüm; W. DeBoer; A. Dierlamm; G. Dirkes; M. Fahrer; M. Frey; A. Furgeri; F. Hartmann; S. Heier; K.-H. Hoffmann; J. Kaminski; B. Ledermann; T. Liamsuwan; S. Müller; Th Müller; F.-P. Schilling; H.-J. Simonis; P. Steck; V. Zhukov; P. Cariola; G. DeRobertis; R. Ferorelli; L. Fiore; M. Preda; G. Sala; L. Silvestris; P. Tempesta; G. Zito; D. Creanza; N. DeFilippis; M. DePalma; D. Giordano; G. Maggi; N. Manna; S. My; G. Selvaggi; S. Albergo; M. Chiorboli; S. Costa; M. Galanti; N. Giudice; N. Guardone; F. Noto; R. Potenza; M. A. Saizu; V. Sparti; C. Sutera; A. Tricomi; C. Tuvè; M. Brianzi; C. Civinini; F. Maletta; F. Manolescu; M. Meschini; S. Paoletti; G. Sguazzoni; B. Broccolo; V. Ciulli; R. D'Alessandro E. Focardi; S. Frosali; C. Genta; G. Landi; P. Lenzi; A. Macchiolo; N. Magini; G. Parrini; E. Scarlini; G. Cerati; P. Azzi; N. Bacchetta; A. Candelori; T. Dorigo; A. Kaminsky; S. Karaevski; V. Khomenkov; S. Reznikov; M. Tessaro; D. Bisello; M. DeMattia; P. Giubilato; M. Loreti; S. Mattiazzo; M. Nigro; A. Paccagnella; D. Pantano; N. Pozzobon; M. Tosi; G. M. Bilei; B. Checcucci; L. Fanò; L. Servoli; F. Ambroglini; E. Babucci; D. Benedetti; M. Biasini; B. Caponeri; R. Covarelli; M. Giorgi; P. Lariccia; G. Mantovani; M. Marcantonini; V. Postolache; A. Santocchia; D. Spiga; G. Bagliesi; G. Balestri; L. Berretta; S. Bianucci; T. Boccali; F. Bosi; F. Bracci; R. Castaldi; M. Ceccanti; R. Cecchi; C. Cerri; A. S. Cucoanes; R. Dell'Orso; D. Dobur; S. Dutta; A. Giassi; S. Giusti; D. Kartashov; A. Kraan; T. Lomtadze; G. A. Lungu; G. Magazzù; P. Mammini; F. Mariani; G. Martinelli; A. Moggi; F. Palla; F. Palmonari; G. Petragnani; A. Profeti; F. Raffaelli; D. Rizzi; G. Sanguinetti; S. Sarkar; D. Sentenac; A. T. Serban; A. Soldani; P. Spagnolo; R. Tenchini; S. Tolaini; A. Venturi; P. G. Verdini; M. Vos; L. Zaccarelli; C. Avanzini; A. Basti; L. Benucci; A. Bocci; U. Cazzola; F. Fiori; S. Linari; M. Massa; A. Messineo; G. Segneri; G. Tonelli; P. Azzurri; J. Bernardini; L. Borrello; F. Calzolari; L. Foà; S. Gennai; F. Ligabue; G. Petrucciani; A. Rizzi; Z. Yang; F. Benotto; N. Demaria; F. Dumitrache; R. Farano; M. A. Borgia; R. Castello; M. Costa; E. Migliore; A. Romero; D. Abbaneo; M. Abbas; I. Ahmed; I. Akhtar; E. Albert; C. Bloch; H. Breuker; S. Butt; O. Buchmuller; A. Cattai; C. Delaere; M. Delattre; L. M. Edera; M. Eppard; M. Gateau; K. Gill; A.-S. Giolo-Nicollerat; R. Grabit; A. Honma; M. Huhtinen; K. Kloukinas; J. Kortesmaa; L. J. Kottelat; N. Leonardo; C. Ljuslin; M. Mannelli; L. Masetti; A. Marchioro; S. Mersi; L. Mirabito; J. Muffat-Joly; A. Onnela; C. Paillard; I. Pal; J. F. Pernot; P. Petagna; C. Piccut; M. Pioppi; H. Postema; R. Ranieri; D. Ricci; G. Rolandi; F. Ronga; C. Sigaud; A. Syed; P. Siegrist; P. Tropea; J. Troska; A. Tsirou; M. Vander Donckt; F. Vasey; E. Alagoz; C. Amsler; V. Chiochia; C. Regenfus; P. Robmann; J. Rochet

2009-01-01

206

Alignment of the CMS silicon strip tracker during stand-alone commissioning  

SciTech Connect

The results of the CMS tracker alignment analysis are presented using the data from cosmic tracks, optical survey information, and the laser alignment system at the Tracker Integration Facility at CERN. During several months of operation in the spring and summer of 2007, about five million cosmic track events were collected with a partially active CMS Tracker. This allowed us to perform first alignment of the active silicon modules with the cosmic tracks using three different statistical approaches; validate the survey and laser alignment system performance; and test the stability of Tracker structures under various stresses and temperatures ranging from +15C to -15C. Comparison with simulation shows that the achieved alignment precision in the barrel part of the tracker leads to residual distributions similar to those obtained with a random misalignment of 50 (80) microns in the outer (inner) part of the barrel.

Adam, W.; et al.

2009-07-01

207

TeraHz tuning of whispering gallery modes in a PDMS, stand-alone, stretchable microsphere  

E-print Network

We report on tuning the optical whispering gallery modes in a poly dimethyl siloxane-based (PDMS) microsphere resonator by more than a THz. The PDMS microsphere system consists of a solid spherical resonator directly formed with double stems on either side. The stems act like tie-rods for simple mechanical stretching of the microresonator over tens of microns, resulting in tuning of the whispering gallery modes by one free spectral range. Further investigations demonstrate that the whispering gallery mode shift has a higher sensitivity (0.13 nm/{\\mu}N) to an applied force when the resonator is in its maximally stretched state compared to its relaxed state.

Madugani, Ramgopal; Ward, Jonathan M; Riordan, John Daniel; Coppola, Sara; Vespini, Veronica; Grilli, Simonetta; Finizio, Andrea; Ferraro, Pietro; Chormaic, Síle Nic

2012-01-01

208

A stand-alone alphanumeric CRT teleprocessor unit for a Hewlett-Packard 2114B minicomputer  

E-print Network

DAC. C DESIGN FOR 3-BIT DAC. D DESIGN FOR DAC SUMMER NETWORKS. Y ITA 85 92 99 106 113 LIST OF FIGURES FIGURE 2. 1 System block diagram. 2. 2 Memory section block diagram. 2. 3 Display processor block diagram . 2. 4 CRT beam racetrack. 2... selected. Nap~ Peoceaaoa The display processor can be broken down into four functional blocks. As shown in Fig. 2. 3, they are a character generator, a video amplifier, a carriage control section, and a dig1tal-to- analog conversion (DAC) section...

Burrage, George Richard

1973-01-01

209

COMPARING UTILITY CONNECTED TO STAND ALONE MICRO-GRIDS: FROM THE VIEWPOINT OF A UTILITY ENGINEER  

SciTech Connect

Project examples of grid connected micro grid & example of grid isolated micro grid: drivers – economic, environmental and financial tools to plan/design modeling software resource options, tools to plan/design generation types, fuel options and services to provide smooth transitions required equipment and software controls minimal expense to maximum functionality, real time operational interfaces, getting it built real world complications and advice. This paper is an attempt to present a broad overview of micro grids, project examples, modeling tools, technology options, practical and business insights to enable those interested in micro-grids to quickly come up to speed on the basics and potentially move forward on their own projects with the tools and resources presented. Knowledge and experience with electrical distribution systems will make such an effort easier.

Hoffman, Michael G.; Russo, Bryan J.

2011-06-23

210

Continuous stand-alone controllable aerosol/cloud droplet dryer for atmospheric sampling  

NASA Astrophysics Data System (ADS)

We describe a general-purpose dryer designed for continuous sampling of atmospheric aerosol, where a specified relative humidity (RH) of the sample flow (lower than the atmospheric humidity) is required. It is often prescribed to measure the properties of dried aerosol, for instance for monitoring networks. The specific purpose of our dryer is to dry cloud droplets (maximum diameter approximately 25 ?m, highly charged, up to 5 × 102 charges). One criterion is to minimise losses from the droplet size distribution entering the dryer as well as on the residual dry particle size distribution exiting the dryer. This is achieved by using a straight vertical downwards path from the aerosol inlet mounted above the dryer, and removing humidity to a dry, closed loop airflow on the other side of a semi-permeable GORE-TEX membrane (total area 0.134 m2). The water vapour transfer coefficient, k, was measured to be 4.6 × 10-7 kg m-2 s-1% RH-1 in the laboratory (temperature 294 K) and is used for design purposes. A net water vapour transfer rate of up to 1.2 × 10-6 kg s-1 was achieved in the field. This corresponds to drying a 5.7 L min-1 (0.35 m3 h-1) aerosol sample flow from 100% RH to 27% RH at 293 K (with a drying air total flow of 8.7 L min-1). The system was used outdoors from 9 May until 20 October 2010, on the mountain Brocken (51.80° N, 10.67° E, 1142 m a.s.l.) in the Harz region in central Germany. Sample air relative humidity of less than 30% was obtained 72% of the time period. The total availability of the measurement system was >94% during these five months.

Sjogren, S.; Frank, G. P.; Berghof, M. I. A.; Martinsson, B. G.

2013-02-01

211

Standing Alone in Judgment  

ERIC Educational Resources Information Center

In this article, Mark Freado and Howard Bath present the case of an 11 year boy who had been arrested and charged with the murder of his two-year-old cousin. Because of the severity of the criminal charge against this boy, and despite his age, a transfer hearing was set to determine whether he would be tried as a juvenile or an adult. Such…

Freado, Mark D.; Bath, Howard I.

2014-01-01

212

Design description of the Schuchuli Village photovoltaic power system  

NASA Astrophysics Data System (ADS)

A stand alone photovoltaic (PV) power system for the village of Schuchuli (Gunsight), Arizona, on the Papago Indian Reservation is a limited energy, all 120 V (d.c.) system to which loads cannot be arbitrarily added and consists of a 3.5 kW (peak) PV array, 2380 ampere-hours of battery storage, an electrical equipment building, a 120 V (d.c.) electrical distribution network, and equipment and automatic controls to provide control power for pumping water into an existing water system; operating 15 refrigerators, a clothes washing machine, a sewing machine, and lights for each of the homes and communal buildings. A solar hot water heater supplies hot water for the washing machine and communal laundry. Automatic control systems provide voltage control by limiting the number of PV strings supplying power during system operation and battery charging, and load management for operating high priority at the expense of low priority loads as the main battery becomes depleted.

Ratajczak, A. F.; Vasicek, R. W.; Delombard, R.

1981-05-01

213

Design description of the Schuchuli Village photovoltaic power system  

NASA Technical Reports Server (NTRS)

A stand alone photovoltaic (PV) power system for the village of Schuchuli (Gunsight), Arizona, on the Papago Indian Reservation is a limited energy, all 120 V (d.c.) system to which loads cannot be arbitrarily added and consists of a 3.5 kW (peak) PV array, 2380 ampere-hours of battery storage, an electrical equipment building, a 120 V (d.c.) electrical distribution network, and equipment and automatic controls to provide control power for pumping water into an existing water system; operating 15 refrigerators, a clothes washing machine, a sewing machine, and lights for each of the homes and communal buildings. A solar hot water heater supplies hot water for the washing machine and communal laundry. Automatic control systems provide voltage control by limiting the number of PV strings supplying power during system operation and battery charging, and load management for operating high priority at the expense of low priority loads as the main battery becomes depleted.

Ratajczak, A. F.; Vasicek, R. W.; Delombard, R.

1981-01-01

214

Design description of the Schuchuli village photovoltaic power system  

SciTech Connect

The engineering design of a stand-alone photovoltaic (PV) power system for the village of Schuchuli (Gunsight), Arizona, on the Papago Indian Reservation is described. The purpose of this experiment was to demonstrate that a stand-alone photovoltaic power system could provide dependable power for basic human needs in a remote village environment. The power system was designed as a limited energy, all 120-V(d.c.) system to which loads cannot be arbitrarily added. The system consists of a 3.5-kW (peak) PV array, 2380 ampere-hours of battery storage, an Electrical Equipment Building, a 120-V(d.c.) electrical distribution network, and equipment and automatic controls to provide control power for pumping water into an existing water system; operating 15 refrigerators, a clothes washing machine, and a sewing machine in the Domestic Services Building; and lights for each of the homes and communal buildings. In addition, a solar hot water heater was provided to supply hot water for the washing machine and communal laundry. The system employs automatic control systems which provide voltage control by limiting the number of PV strings supplying power during system operation and battery charging, and load management for operating high priority loads at the expense of low priority loads as the main battery becomes depleted. The engineering design includes loads profiles and loads descriptions; an explanation of the PV array and battery sizing methodology; descriptions of the mechanical designs; electrical designs and descriptions of the array, battery, controls, instrumentation and distribution system; and a discussion of safety features.

Ratajczak, A.F.; Vasicek, R.W.; DeLombard, R.

1981-05-01

215

Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States. (UNH)  

EPA Science Inventory

The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

216

Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States  

EPA Science Inventory

The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

217

Development of a fuel cell power conditioner system  

Microsoft Academic Search

The fuel cell is an alternative power generation method which is envisaged to be environmentally friendly and efficient. It can be an attractive solution for various “clean power” applications such as an electric vehicle. It can also be suitably used as a stand alone power generator. The fuel cell converts chemical energy into electrical energy by means of an electrochemical

K. M. Salim; Zainal Salam; Faridah Taha; A. H. M. Yatim

1999-01-01

218

Numerical simulations of a low power microchannel thermal cycling reactor  

Microsoft Academic Search

A roadblock to the development of stand-alone microscale biomedical and chemical analysis systems is the relatively high heating power requirement of the microscale reactors, which typically exceeds the capability of low cost batteries. In this study, a microchannel thermal cycling reactor design using in-channel heating and passive cooling is proposed and a numerical model has been developed. Numerical simulations were

David Erickson; Dongqing Li

2002-01-01

219

Outcomes for Elderly Patients with Mental Illness Following Relocation from a Stand-Alone Psychiatric Hospital to Community-Based Extended Care Units  

Microsoft Academic Search

Objective: To assess the outcomes for a group of elderly patients with mental illness following their discharge from a stand-alone psychiatric facility to seven extended care units (ECUs).Method: All patients (n = 60) who were relocated to the ECUs were assessed using a number of standardized clinical and general functioning instruments at 6 months and 6 weeks pre-move, and again

Tom Meehan; Samantha Robertson; Terry Stedman; Gerard Byrne

2004-01-01

220

Injury of the right and left inferior epigastric artery during the implantation of a stand-alone ALIF cage through a left retroperitoneal approach: a case report  

Microsoft Academic Search

Various perioperative vascular complications of anterior lumbar spine procedures have been described in orthopaedic literature.\\u000a We report the unusual case of a perioperative bleeding from the right and left epigastric inferior artery occurring when using\\u000a a stand-alone ALIF device (Synfix, Synthes, Oberdorf, Switzerland) at the L5\\/S1 level through an anterior left retroperitoneal\\u000a approach. The primary stability of the Synfix is

Martin Thaler; E. Mayr; M. Liebensteiner; C. M. Bach

2010-01-01

221

Photovoltaic Power System and Power Distribution Demonstration for the Desert RATS Program  

NASA Technical Reports Server (NTRS)

A stand alone, mobile photovoltaic power system along with a cable deployment system was designed and constructed to take part in the Desert Research And Technology Studies (RATS) lunar surface human interaction evaluation program at Cinder Lake, Arizona. The power system consisted of a photovoltaic array/battery system. It is capable of providing 1 kW of electrical power. The system outputs were 48 V DC, 110 V AC, and 220 V AC. A cable reel with 200 m of power cable was used to provide power from the trailer to a remote location. The cable reel was installed on a small trailer. The reel was powered to provide low to no tension deployment of the cable. The cable was connected to the 220 V AC output of the power system trailer. The power was then converted back to 110 V AC on the cable deployment trailer for use at the remote site. The Scout lunar rover demonstration vehicle was used to tow the cable trailer and deploy the power cable. This deployment was performed under a number of operational scenarios, manned operation, remote operation and tele-robotically. Once deployed, the cable was used to provide power, from the power system trailer, to run various operational tasks at the remote location.

Colozza, Anthony; Jakupca, Ian; Mintz, Toby; Herlacher, Mike; Hussey, Sam

2012-01-01

222

Market assessment of photovoltaic power systems for agricultural applications in Nigeria  

SciTech Connect

The results of a month-long study in Nigeria conducted in February 1981 are detailed. The study was aimed at assessing in the 1981 to 1986 market potential for stand-alone photovoltaic systems in agriculture. Information on technically and economically feasible applications, and assessments of business, government and financial climate for photovoltaic sales are provided. The study concluded that the market for stand-alone photovoltaic power systems will be large, the primary reasons being the availability of capital and the high premium placed on high reliability, low maintenance power systems. A market exists for such agricultural/rural applications as: micro-irrigation, veterinary units, grain grinding, dryers, produce coolers, ice makers, water/boreholes, and health, education and extension services. Other markets with high PV sales potential include: remote local government centers, public and private communication systems, TV battery chargers, domestic power supply and cathodic protection. The potential market for photovoltaics in the 1981 to 1986 time frame is estimated at about 1.9 to 4.7 MW. The major purchaser in the near-term would be the federal and state governments.

Staples, D.; Steingass, H.; Nolfi, J.

1981-10-01

223

Adaptive wide area protection of power systems  

NASA Astrophysics Data System (ADS)

Studies of major blackouts reveal that power system protection devices have contributed to a majority of system disturbances. This leads to efforts of improving protection philosophy. Analysis shows that conventional protection relies on coordination among stand-alone relays to obtain a dependability-biased component-protection scheme. Whereas it is more desirable and also feasible nowadays for an integrated approach to both component and system protection, provided modern relays possessing the ability of sharing information and applying intelligence in decision-making. This dissertation proposes the adaptive protection concept for wide area systems. The scope of the research includes identifying and developing the desired architecture, intelligent algorithms and communication needs that facilitate the protection system to avoid and reduce the impact of system emergencies. The purpose of this research work is to conceptualize and nurture adaptive protection concept for wide area systems, and to conduct feasibility studies to make this concept practically viable. Several case studies are conducted to show the effectiveness of the proposed adaptive protection scheme. In addition, voltage stability, which is a classic wide area problem, can be alleviated with the proposed concept. Steady state and transient simulation studies provided encouraging results. The detailed decision-making algorithms are simulated in several examples for validation of the concept.

Huang, Jiang

224

ANALYSIS OF THE TURBULENT HEAT TRANSFER IN SOLAR POWER TOWER MOLTEN SALT RECEIVER TUBE  

Microsoft Academic Search

Central Receiver System (CRS) with molten salt (MS) technology represents the most cost effective and leading candidate technology for electricity generation for stand-alone Solar Power Plants. But MS has a high freezing point, and the tube alloy also can not stand long time with high temperature in MS circumstances. Tube freezing, leaking and salt decomposing are very likely to happen

Chun Chang; Zhifeng Wang; Xin Li; Fengwu Bai; Yong-Heack Kang; Jong-Kyu Kim

225

Single inductor quad-input-dual-output buck converter for photovoltaic systems  

Microsoft Academic Search

Stand-alone photovoltaic (SAPV) system is more favourable than grid connected photovoltaic (PV) system in areas where extension of power grid is impracticable. However, the high set up cost of a SAPV system requires cost efficient solar energy harvesting methods. To improve the energy harvesting efficiency of a PV system, a large, centrally controlled PV array can be rearranged into smaller

K. W. R. Chew; L. Siek

2010-01-01

226

Power Systems Development Facility. Environmental Assessment  

SciTech Connect

The objective of the PSDF would be to provide a modular facility which would support the development of advanced, pilot-scale, coal-based power systems and hot gas clean-up components. These pilot-scale components would be designed to be large enough so that the results can be related and projected to commercial systems. The facility would use a modular approach to enhance the flexibility and capability for testing; consequently, overall capital and operating costs when compared with stand-alone facilities would be reduced by sharing resources common to different modules. The facility would identify and resolve technical barrier, as well as-provide a structure for long-term testing and performance assessment. It is also intended that the facility would evaluate the operational and performance characteristics of the advanced power systems with both bituminous and subbituminous coals. Five technology-based experimental modules are proposed for the PSDF: (1) an advanced gasifier module, (2) a fuel cell test module, (3) a PFBC module, (4) a combustion gas turbine module, and (5) a module comprised of five hot gas cleanup particulate control devices. The final module, the PCD, would capture coal-derived ash and particles from both the PFBC and advanced gasifier gas streams to provide for overall particulate emission control, as well as to protect the combustion turbine and the fuel cell.

Not Available

1993-06-01

227

Renewable Energy Systems With Photovoltaic Power Generators: Operation and Modeling  

Microsoft Academic Search

A substantial increase of photovoltaic (PV) power generators installations has taken place in recent years, due to the increasing efficiency of solar cells as well as the improvements of manufacturing technology of solar panels. These generators are both grid-connected and stand-alone applications. We present an overview of the essential research results. The paper concentrates on the operation and modeling of

Jan T. Bialasiewicz

2008-01-01

228

Prospective Randomized Controlled Trial of The Stabilis Stand Alone Cage (SAC) Versus Bagby and Kuslich (BAK) Implants for Anterior Lumbar Interbody Fusion  

PubMed Central

Background Degenerative disc disease is common and debilitating for many patients. If conservative extensive care fails, anterior lumbar interbody fusion has proven to be an alternative form of surgical management. The Stabilis Stand Alone Cage(SAC) was introduced as a method to obtain stability and fusion. The purpose of this study was to determine whether the Stabilis Stand Alone Cage (SAC) is comparable in safety and efficacy to the Bagby and Kuslich (BAK) device. Methods As part of a prospective, randomized, controlled FDA trial, 73 patients underwent anterior interbody fusion using either the SAC(56%) or the BAK device (44%). Results Background characteristics were similar between the two groups. There was no significant difference between the SAC and BAK groups in mean operative time or mean blood loss during surgery. Adverse event rates did not differ between the groups. Assessment of plain radiographs could not confirm solid fusion in 63% of control and 71% of study patients. Functional scores from Owestry and SF-36 improved in both groups by the two-year follow-up. There were no significant differences between the SAC and BAK patients with respect to outcome. Conclusions Both the Stabilis Stand Alone Cage and the BAK Cage provided satisfactory improvement in function and pain relief, despite less than expected radiographic fusion rates. The apparent incongruency between fusion rates and functional outcomes suggests that either radiographs underestimate the true incidence of fusion, or that patients are obtaining good pain relief and improved function despite a lower rate of fusion than previously reported. This was a Level III study. PMID:25694930

Lavelle, William; McLain, Robert F.; Rufo-Smith, Candace; Gurd, David P.

2014-01-01

229

Description of photovoltaic village power systems in the United States and Africa  

NASA Technical Reports Server (NTRS)

The paper describes the designs, hardware, and installations of NASA photovoltaic power systems in the village of Schuchuli in Arizona and Tangaye in Upper Volta, Africa. The projects were designed to demonstrate that current photovoltaic system technology can provide electrical power for domestic services for small, remote communities. The Schuchuli system has a 3.5 kW peak solar array which provides power for water pumping, a refrigerator for each family, lights, and community washing and sewing machines. The 1.8 kW Tangaye system provides power for pumping, flour milling, and lights in the milling building. Both are stand-alone systems operated by local personnel, and they are monitored by NASA to measure design adequacy and refine future designs.

Ratajczak, A. F.; Bifano, W. J.

1979-01-01

230

Modelling and control of standalone solar photovoltaic charging system  

Microsoft Academic Search

The photovoltaic (PV) stand-alone system requires a battery charger for energy storage. This paper presents the modelling and control design of the PV charger system using Buck-Boost converter. The voltage command is determined by both the PV module maximum power point tracking (MPPT) control loop and the battery charging loop. Here the controller is designed so as to balance the

B. Sree Manju; R. Ramaprabha; B. L. Mathur

2011-01-01

231

Current demand of high performance inverters for renewable energy systems  

Microsoft Academic Search

This paper points out that versatile stand-alone renewable energy systems demand on at least one robust battery inverter. Despite of the employed system configuration, it is shown that the battery inverter should be capable to practically support all load demand. In practice, improved characteristics of reliability, surge power capability and efficiency are essential to guarantee long term and flexible operation

Sérgio Daher; Jürgen Schmid; Fernando Antunes

2007-01-01

232

The Hardware Helper: Taking the Guesswork out of Multimedia Systems.  

ERIC Educational Resources Information Center

A computer expert describes two stand-alone, multimedia CD-ROM computer systems suitable for school and public libraries: a budget version for less than $2000 and a power version for about $3000. Recommends specific personal computer models, monitors, operating systems, processors, RAM (random access memory), hard drives, video subsystems, CD-ROM…

Jacso, Peter

1996-01-01

233

Determining the optimum solar water pumping system for domestic use, livestock water, or irrigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

For several years we have field tested many different types of solar powered water pumping systems. In this paper, several steps are given to select a solar-PV water pumping system. The steps for selection of stand-alone water pumping system were: deciding whether a wind or solar water pumping sys...

234

Power system  

DOEpatents

A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

Hickam, Christopher Dale (Glasford, IL)

2008-03-18

235

Comparison between Two Different Cervical Interbody Fusion Cages in One Level Stand-alone ACDF: Carbon Fiber Composite Frame Cage Versus Polyetheretherketone Cage  

PubMed Central

Objective The authors conducted a retrospective study to compare the implantation of carbon fiber composite frame cages (CFCFCs) to the implantation of polyetheretherketone (PEEK) cages after anterior cervical discectomy for cervical degenerative disc disease. In addition, the predictive factors that influenced fusion or subsidence were investigated. Methods A total of 58 patients with single-level degenerative disc disease were treated with anterior cervical discectomy and implantation of stand-alone cages; CFCFCs were used in 35 patients, and PEEK cages were used in 23 patients. Preoperative and postoperative radiological and clinical assessments were performed. Results During the mean follow-up period of 41 months, fusion occurred in 43 patients (74.1%), and subsidence developed in 18 patients (31.0%). Pain decreased in all patients, and the patients' satisfaction rate was 75.9%. Neither fusion nor subsidence was related to the clinical outcome. There were no significant differences in the clinical and radiological outcomes between the CFCFC and the PEEK cage groups. Smoking history (p=0.023) was significantly associated with pseudarthrosis, and cage height (?7mm) (p=0.037) were significantly associated with subsidence. Conclusion The clinical and radiological results were similar between the CFCFC and the PEEK cage groups. Fusion or subsidence did not affect the clinical outcomes. Smoking history and cage height (?7mm) were predictive factors for pseudarthrosis or subsidence in anterior cervical discectomy and fusion with stand-alone cages. PMID:25346758

Yoo, Minwook; Kim, Wook-Ha; Hyun, Seung-Jae; Jahng, Tae-Ahn; Kim, Hyun-Jib

2014-01-01

236

Control of solid oxide fuel cell for stand-alone and grid connection using fuzzy logic technique  

Microsoft Academic Search

Fuel cells are very promising sources of electricity; environmentally safe and very efficient. The fuel cells have numerous applications: houses, industries, hospitals, vehicles etc. Another facet of these fuel cell applications is distributed generation, the implementation of various power generating resources, near the site of need, for reducing reliance on grid power. Fuel cells generate electricity from hydrogen by a

A. R. Sakehare; Asad Davari; Ali Feliachi

2004-01-01

237

Low-frequency switching voltage regulators for terrestrial photovoltaic systems  

NASA Technical Reports Server (NTRS)

The photovoltaic technology project and the stand alone applications project are discussed. Two types of low frequency switching type regulators were investigated. The design, operating characteristics and field application of these regulators is described. The regulators are small in size, low in cost, very low in power dissipation, reliable and allow considerable flexibility in system design.

Delombard, R.

1984-01-01

238

Integrating an embedded system in a microwave moisture meter  

Technology Transfer Automated Retrieval System (TEKTRAN)

The conversion of a PC- or laptop-controlled microwave moisture meter to a stand-alone meter hosting its own embedded system is discussed. The moisture meter measures the attenuation and phase shift of low power microwaves traversing the sample, from which the dielectric properties are calculated. T...

239

Integrating an Embedded System within a Microwave Moisture Meter  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this paper, the conversion of a PC or laptop-controlled microwave moisture meter to a stand-alone meter hosting its own embedded system is discussed. The moisture meter uses low-power microwaves to measure the attenuation and phase shift of the sample, from which the dielectric properties are cal...

240

Design considerations for a 48 V fuel cell to split single phase inverter system with ultracapacitor energy storage  

Microsoft Academic Search

Fuel cells are a versatile, renewable energy source that can be used in a wide range of applications. In this paper, topologies for a 10 kW inverter system with a low voltage fuel cell input are evaluated based on simplicity, performance, and cost. This particular fuel cell system is intended for household stand-alone power generation. The inverter proposed has a

Troy A. Nergaard; Jeremy F. Ferrell; Leonard G. Leslie; Jih-Sheng Lai

2002-01-01

241

Power systems  

NASA Astrophysics Data System (ADS)

Significant events in current, prototype, and experimental utility power generating systems in 1981 are reviewed. The acceleration of licensing and the renewal of plans for reprocessing of fuel for nuclear power plants are discussed, including the rise of French reactor-produced electricity to over 40% of the country's electrical output. A 4.5 MW fuel cell neared completion in New York City, while three 2.5 MW NASA-designed windpowered generators began producing power in the state of Washington. Static bar compensators, nonflammable-liquid cooled power transformers, and ZnO surge arrestors were used by utilities for the first time, and the integration of a coal gasifier-combined cycle power plant approached the planning phase. An MHD generator was run for 1000 hours and produced 50-60 kWe, while a 20 MVA superconducting generator was readied for testing.

Kaplan, G.

1982-01-01

242

Embedding video in stand alone test equipment to eliminate training for low-volume, high mix manufacturing and field diagnostics  

Microsoft Academic Search

A common problem in supporting system readiness is the training required to operate test and diagnostic systems. Newly enlisted personnel, or multinationals not fluent in English, are often called upon to operate and maintain complex, high-value, low-volume systems with a minimum of training. Cost and availability of highly skilled technicians versus user interface development is frequently a major consideration in

K. K. Johnson

2003-01-01

243

Solution and crystal structure of BA42, a protein from the Antarctic bacterium Bizionia argentinensis comprised of a stand-alone TPM domain.  

PubMed

The structure of the BA42 protein belonging to the Antarctic flavobacterium Bizionia argentinensis was determined by nuclear magnetic resonance and X-ray crystallography. This is the first structure of a member of the PF04536 family comprised of a stand-alone TPM domain. The structure reveals a new topological variant of the four ?-strands constituting the central ?-sheet of the ??? architecture and a double metal binding site stabilizing a pair of crossing loops, not observed in previous structures of proteins belonging to this family. BA42 shows differences in structure and dynamics in the presence or absence of bound metals. The affinity for divalent metal ions is close to that observed in proteins that modulate their activity as a function of metal concentration, anticipating a possible role for BA42. PMID:25116514

Aran, Martin; Smal, Clara; Pellizza, Leonardo; Gallo, Mariana; Otero, Lisandro H; Klinke, Sebastián; Goldbaum, Fernando A; Ithurralde, Esteban R; Bercovich, Andrés; Mac Cormack, Walter P; Turjanski, Adrián G; Cicero, Daniel O

2014-11-01

244

Alternative energy facilities based on site matching and generation unit sizing for remote area power supply  

Microsoft Academic Search

This paper presents the decision support technique and influencing factors in the design of an integrated solar-wind power system for stand-alone applications. Results of investigations on application of alternative energy facility like wind, photovoltaic (PV), and Integration of wind–PV power generating systems for Remote Area Power Supply have been presented. A weather model-based site matching of equipment and a simple

Pradeep K. Katti; Mohan K. Khedkar

2007-01-01

245

Effects of ozone as a stand-alone and coagulation-aid treatment on the reduction of trihalomethanes precursors from high DOC and hardness water.  

PubMed

This study investigates the effect of ozone as a stand-alone and coagulation aid on the removal of dissolved organic carbon (DOC) from the water with a high level of DOC (13.8 mgL(-1)) and calcium hardness (270 mgL(-1)) CaCO3. Natural water collected from the Assiniboine River (Manitoba, Canada) was used in this study. Effectiveness of ozone treatment was evaluated by measurement of DOC, DOC fractions, UV254, and trihalomethane formation potential (THMFP). Additionally, zeta potential and dissolved calcium concentration were measured to discern the mechanism of ozone reactions. Results indicated that 0.8 mg O3/mg DOC ozone stand-alone can cause up to 86% UV254 reduction and up to 27% DOC reduction. DOC fractionation results showed that ozone can change the composition of DOC in the water samples, converting the hydrophobic fractions into hydrophilic ones and resulting in the reduction of THMFP. Also, ozone caused a decrease in particle stability and dissolved calcium concentration. These simultaneous ozonation effects caused improved water flocculation and enhanced removal of DOC. This resulted in reduction of the coagulant dosage when ozone doses higher than 0.2 mg O3/mg DOC were applied prior to coagulation with ferric sulfate. Also, pre-ozonation-coagulation process achieved preferential THMFP removal for all of the ozone doses tested (0-0.8 mg O3/mg DOC), leading to a lower specific THMFP in pre-ozonated-coagulated waters than in the corresponding ozonated waters. PMID:25659964

Sadrnourmohamadi, Mehrnaz; Gorczyca, Beata

2015-04-15

246

LCL Filter Design and Performance Analysis for Grid Interconnected Systems , M.Godoy Simes*  

E-print Network

--filter; harmonics; inverter; power quality; pulse width-modulated (PWM) inverters; I. INTRODUCTION Voltage source inverters (VSI) are used for energy conversion from a DC source to an AC output, both in a stand- alone mode, and are inductors resistances, voltages and are the input and output (inverter voltage and output system voltage

Simões, Marcelo Godoy

247

Study on Cosmic Ray Background Rejection with a 30 m Stand-Alone IACT using Non-parametric Multivariate Methods in a sub-100 GeV Energy Range  

E-print Network

During the last decade ground-based very high-energy gamma-ray astronomy achieved a remarkable advancement in the development of the observational technique for the registration and study of gamma-ray emission above 100 GeV. It is widely believed that the next step in its future development will be the construction of telescopes of substantially larger size than the currently used 10 m class telescopes. This can drastically improve the sensitivity of the ground-based detectors for gamma rays of energy from 10 to 100 GeV. Based on Monte Carlo simulations of the response of a single stand-alone 30 m imaging atmospheric Cherenkov telescope (IACT) the maximal rejection power against background cosmic ray showers for low energy gamma-rays was investigated in great detail. An advanced Bayesian multivariate analysis has been applied to the simulated Cherenkov light images of the gamma-ray- and proton-induced air showers. The results obtained here quantitatively testify that the separation between the signal and background images degrades substantially at low energies, and consequently the maximum overall quality factor can only be about 3.1 for gamma rays in the 10-30 GeV energy range. Various selection criteria as well as optimal combinations of the standard image parameters utilized for effective image separation have been also evaluated.

A. Konopelko; A. Chilingarian; A. Reimers

2006-11-29

248

Community health workers and stand-alone or integrated case management of malaria: a systematic literature review.  

PubMed

A systematic literature review was conducted to assess the effectiveness of strategies to improve community case management (CCM) of malaria. Forty-three studies were included; most (38) reported indicators of community health worker (CHW) performance, 14 reported on malaria CCM integrated with other child health interventions, 16 reported on health system capacity, and 13 reported on referral. The CHWs are able to provide good quality malaria care, including performing procedures such as rapid diagnostic tests. Appropriate training, clear guidelines, and regular supportive supervision are important facilitating factors. Crucial to sustainable success of CHW programs is strengthening health system capacity to support commodity supply, supervision, and appropriate treatment of referred cases. The little evidence available on referral from community to health facility level suggests that this is an area that needs priority attention. The studies of integrated CCM suggest that additional tasks do not reduce the quality of malaria CCM provided sufficient training and supervision is maintained. PMID:24957538

Smith Paintain, Lucy; Willey, Barbara; Kedenge, Sarah; Sharkey, Alyssa; Kim, Julia; Buj, Valentina; Webster, Jayne; Schellenberg, David; Ngongo, Ngashi

2014-09-01

249

Three-Dimensional Virtual Model of the Human Temporal Bone: A Stand-Alone, Downloadable Teaching Tool  

PubMed Central

Objective To develop a three-dimensional virtual model of a human temporal bone based on serial histologic sections. Background The three-dimensional anatomy of the human temporal bone is complex, and learning it is a challenge for students in basic science and in clinical medicine. Methods Every fifth histologic section from a 14-year-old male was digitized and imported into a general purpose three-dimensional rendering and analysis software package called Amira (version 3.1). The sections were aligned, and anatomic structures of interest were segmented. Results The three-dimensional model is a surface rendering of these structures of interest, which currently includes the bone and air spaces of the temporal bone; the perilymph and endolymph spaces; the sensory epithelia of the cochlear and vestibular labyrinths; the ossicles and tympanic membrane; the middle ear muscles; the carotid artery; and the cochlear, vestibular, and facial nerves. For each structure, the surface transparency can be individually controlled, thereby revealing the three-dimensional relations between surface landmarks and underlying structures. The three-dimensional surface model can also be “sliced open” at any section and the appropriate raw histologic image superimposed on the cleavage plane. The image stack can also be resectioned in any arbitrary plane. Conclusion This model is a powerful teaching tool for learning the complex anatomy of the human temporal bone and for relating the two-dimensional morphology seen in a histologic section to the three-dimensional anatomy. The model can be downloaded from the Eaton-Peabody Laboratory web site, packaged within a cross-platform freeware three-dimensional viewer, which allows full rotation and transparency control. PMID:16791035

Wang, Haobing; Northrop, Clarinda; Burgess, Barbara; Liberman, M. Charles; Merchant, Saumil N.

2007-01-01

250

Determination of tropospheric aerosol characteristics by spectral measurements of solar radiation using a compact, stand-alone spectroradiometer.  

PubMed

We developed a method for characterizing atmospheric properties from ground-based, spectral measurements of direct and scattered solar radiation under clear sky conditions. A compact spectroradiometer is employed for radiation measurement in the wavelength range between 350 and 1050 nm with a resolution of 10 nm. Spectral matching of measured and simulated spectra yields a set of optical parameters that describe optical characteristics of tropospheric aerosols. We utilize the radiative transfer code MODTRAN4 for constructing realistic atmospheric models. Details of the system calibration, analysis procedure, and the results of its performance test are described. PMID:20220902

Manago, Naohiro; Kuze, Hiroaki

2010-03-10

251

JChainsAnalyser: an ImageJ-based stand-alone application for the study of magneto-rheological fluids  

NASA Astrophysics Data System (ADS)

JChainsAnalyser is a Java-based program for the analysis of two-dimensional images of magneto-rheological fluids (MRF) at low concentration of particles obtained using the video-microscopy technique. MRF are colloidal dispersions of micron-sized polarizable particles in a carrier fluid with medium to low viscosity. When a magnetic field is applied to the suspension, the particles aggregate forming chains or clusters. Aggregation dynamics [P. Domínguez-García, S. Melle, J.M. Pastor, M.A. Rubio, Phys. Rev. E 76 (2007) 051403] and morphology of the aggregates [P. Domínguez-García, S. Melle, M.A. Rubio, J. Colloid Interface Sci. 333 (2009) 221-229] have been studied capturing images of the fluid and analyzing them by using this software. The program allows to analyze automatically the MRF images by means of an adequate combination of different imaging methods, while magnitudes and statistics are calculated and saved in data files. It is possible to run the program on a desktop computer, using the GUI (graphical user interface), or in a cluster of processors or remote computer by means of command-line instructions. Program summaryProgram title: JChainsAnalyser Catalogue identifier: AEDT_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDT_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 79 071 No. of bytes in distributed program, including test data, etc.: 4 367 909 Distribution format: tar.gz Programming language: Java 2 Computer: Any computer with Java Runtime Environment (JRE) installed Operating system: Any OS with Java Runtime Environment (JRE) installed RAM: Typically, 3.3 MB Classification: 23 External routines: ImageJ, ij-imageIO, jdom, L2FProd Nature of problem: The video-microscopy technique usually produces quite a big quantity of images to analyze. Although ImageJ gives the required filters and methods for image analysis, it fails when a large number of images is used. Moreover, an adequate combination of filters is needed for the segmentation and binarization of this kind of images. Solution method: JChainsAnalyser filters and analyses any quantity of MRF images automatically, so the application can be run on a desktop computer or using a cluster of processors. It can be run in a desktop computer using the GUI (graphical user interface) or by a command-line interface. JChainsAnalyser uses XML files to define input/output data and Java to ensure portability between operating systems. It also utilizes an image algorithm based on the application of different and adaptative ImageJ's filters. Running time: The test run provided takes only a few seconds.

Domínguez-García, P.; Rubio, M. A.

2009-10-01

252

Optimal dispatch strategy in remote hybrid power systems  

SciTech Connect

For small villages in developing countries, local stand-alone power systems are often more cost-effective than utility grid extension. Various combinations of wind turbine generators, photovoltaic arrays, diesel gensets, and batteries - remote hybrid power systems - may be preferred to diesel-only systems. Dispatch strategy is the aspect of control strategy that pertains to energy flows among components. In systems with both batteries and diesel genset(s), dispatch affects the life-cycle cost through both the fuel usage and the battery life. In this study, dispatch strategies are compared using (1) an analysis of cost trade-offs, (2) a simple, quasi-steady-state time-series model, and finally (3) HYBRID2, a more sophisticated stochastic time-series model. An idealized predictive dispatch strategy, based on assumed perfect knowledge of future load and wind conditions, is developed and used as a benchmark in evaluating simple, non-predictive strategies. The results illustrate the nature of the optimal strategy and indicate that one of two simple diesel dispatch strategies - either load-following or full power for a minimum run time - can, in conjunction with the frugal use of stored energy (the Frugal Discharge Strategy), be virtually as cost-effective as the Ideal Predictive Strategy. The optimal choice of these two simple charging strategies is correlated to three dimensionless parameters, yielding a generalized dispatch design chart for an important class of systems. 30 refs., 17 figs., 3 tabs.

Barley, C.D.; Winn, C.B. [Colorado State Univ., Fort Collins, CO (United States)

1996-10-01

253

Design description of the Tangaye Village photovoltaic power system  

NASA Astrophysics Data System (ADS)

The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

Martz, J. E.; Ratajczak, A. F.

1982-06-01

254

Design description of the Tangaye Village photovoltaic power system  

NASA Technical Reports Server (NTRS)

The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

Martz, J. E.; Ratajczak, A. F.

1982-01-01

255

Market assessment of photovoltaic power systems for agricultural applications in the Philippines  

NASA Technical Reports Server (NTRS)

The market potential in the Philippines for stand alone photovoltaic (P/V) systems in agriculture was assessed. Applications include: irrigation, postharvest operation, food and fiber processing and storage, and livestock and fisheries operations. Power and energy use profiles for many applications as well as assessments of business, government and financial climate for P/V sales are described. Many characteristics of the Philippine agriculture and energy sector favorably influence the use of P/V systems. However, serious and significant barriers prevent achieving the technically feasible, cost competitive market for P/V systems in the agricultural sector. The reason for the small market is the limited availability capital for financing P/V systems. It is suggested that innovative financing schemes and promotional campaigns should be devised.

Cabraal, R. A.; Delasanta, D.; Burrill, G.

1981-01-01

256

Market assessment of photovoltaic power systems for agricultural applications in the Philippines  

NASA Astrophysics Data System (ADS)

The market potential in the Philippines for stand alone photovoltaic (P/V) systems in agriculture was assessed. Applications include: irrigation, postharvest operation, food and fiber processing and storage, and livestock and fisheries operations. Power and energy use profiles for many applications as well as assessments of business, government and financial climate for P/V sales are described. Many characteristics of the Philippine agriculture and energy sector favorably influence the use of P/V systems. However, serious and significant barriers prevent achieving the technically feasible, cost competitive market for P/V systems in the agricultural sector. The reason for the small market is the limited availability capital for financing P/V systems. It is suggested that innovative financing schemes and promotional campaigns should be devised.

Cabraal, R. A.; Delasanta, D.; Burrill, G.

1981-04-01

257

Market assessment of photovoltaic power systems for agricultural applications worldwide  

NASA Astrophysics Data System (ADS)

Agricultural sector PV market assessments conducted in the Phillippines, Nigeria, Mexico, Morocco, and Colombia are extrapolated worldwide. The types of applications evaluated are those requiring less than 15 kW of power and operate in a stand alone mode. The major conclusions were as follows: PV will be competitive in applications requiring 2 to 3 kW of power prior to 1983; by 1986 PV system competitiveness will extend to applications requiring 4 to 6 kW of power, due to capital constraints, the private sector market may be restricted to applications requiring less than about 2 kW of power; the ultimate purchase of larger systems will be governments, either through direct purchase or loans from development banks. Though fragmented, a significant agriculture sector market for PV exists; however, the market for PV in telecommunications, signalling, rural services, and TV will be larger. Major market related factors influencing the potential for U.S. PV Sales are: lack of awareness; high first costs; shortage of long term capital; competition from German, French and Japanese companies who have government support; and low fuel prices in capital surplus countries. Strategies that may aid in overcoming some of these problems are: setting up of a trade association aimed at overcoming problems due to lack of awareness, innovative financing schemes such as lease arrangements, and designing products to match current user needs as opposed to attempting to change consumer behavior.

Cabraal, A.; Delasanta, D.; Rosen, J.; Nolfi, J.; Ulmer, R.

1981-11-01

258

Market assessment of photovoltaic power systems for agricultural applications worldwide  

NASA Technical Reports Server (NTRS)

Agricultural sector PV market assessments conducted in the Phillippines, Nigeria, Mexico, Morocco, and Colombia are extrapolated worldwide. The types of applications evaluated are those requiring less than 15 kW of power and operate in a stand alone mode. The major conclusions were as follows: PV will be competitive in applications requiring 2 to 3 kW of power prior to 1983; by 1986 PV system competitiveness will extend to applications requiring 4 to 6 kW of power, due to capital constraints, the private sector market may be restricted to applications requiring less than about 2 kW of power; the ultimate purchase of larger systems will be governments, either through direct purchase or loans from development banks. Though fragmented, a significant agriculture sector market for PV exists; however, the market for PV in telecommunications, signalling, rural services, and TV will be larger. Major market related factors influencing the potential for U.S. PV Sales are: lack of awareness; high first costs; shortage of long term capital; competition from German, French and Japanese companies who have government support; and low fuel prices in capital surplus countries. Strategies that may aid in overcoming some of these problems are: setting up of a trade association aimed at overcoming problems due to lack of awareness, innovative financing schemes such as lease arrangements, and designing products to match current user needs as opposed to attempting to change consumer behavior.

Cabraal, A.; Delasanta, D.; Rosen, J.; Nolfi, J.; Ulmer, R.

1981-01-01

259

How Does Drug Treatment for Diabetes Compare between Medicare Advantage Prescription Drug Plans (MAPDs) and Stand-Alone Prescription Drug Plans (PDPs)?  

PubMed Central

Objective To compare the use of guideline-recommended prescription medications for diabetes among Medicare beneficiaries enrolled in stand-alone prescription drug plans (PDPs) with Medicare Advantage prescription drug plans (MAPDs) in the presence of potential selection bias. Data Sources/Study Setting Centers for Medicare and Medicaid Services' Chronic Condition Data Warehouse (2006, 2007). Study Design Retrospective cross-sectional comparison of drug use and proportion of days covered (PDC) for oral-antidiabetics, ACE-inhibitors/ARBs, and antihyperlipidemics among PDP and MAPD enrollees with diabetes. We estimated “naïve” regression models assuming exogenous plan choice and two-stage residual inclusion (2SRI) models to study endogeneity in choice of Part D plan type. Data Collection/Extraction Methods We identified 111,290 diabetics based on ICD-9 codes in Medicare claims from a random 5 percent sample of Medicare beneficiaries in 2005 excluding dual eligibles. Principal Findings The naïve regression models indicated lower probability of drug use for oral-antidiabetics (?4 percent; p < .001) and ACE-inhibitors/ARBS (?2 percent; p = .004) among PDP enrollees, but their PDC was higher (3–5 percent) for all drug classes (p < .001). 2SRI models produced no significant differences in any-use equations, but significantly higher PDC values for PDP enrollees for oral-antidiabetics and ACE-inhibitors/ARBs. Conclusions We found similar overall use of recommended drugs in diabetes treatment and no consistent evidence of favorable or adverse selection into PDPs and MAPDs. PMID:23205568

Erten, Mujde Z; Stuart, Bruce; Davidoff, Amy J; Shoemaker, J Samantha; Bryant-Comstock, Lynda; Shenolikar, Rahul

2013-01-01

260

DESIGN OF HYBRID-PHOTOVOLTAIC POWER GENERATOR, WITH OPTIMIZATION OF ENERGY MANAGEMENT  

Microsoft Academic Search

A methodology is developed for calculating the correct size of a photovoltaic (PV)-hybrid system and for optimizing its management. The power for the hybrid system comes from PV panels and an engine-generator – that is, a gasoline or diesel engine driving an electrical generator. The combined system is a stand-alone or autonomous system, in the sense that no third energy

M. Muselli; G. Notton; A. Louche

1999-01-01

261

Distributed-dispersed renewable energy systems and novel control strategies  

NASA Astrophysics Data System (ADS)

Renewable green-energy systems are re-emerging as viable economic alternative sources of environmentally safe power generation in place of conventional fossil fuels. In terms of power quality and safety, this research investigates a number of renewable green-energy (wind, photovoltaic and fuel cells) interface schemes and control strategies that ensure maximum energy utilization, voltage and frequency stabilization and minimum impact on the host electric grid systems. The research key objectives are to study efficient and robust renewable energy converter schemes with associated control strategies and validate their operations for both stand-alone and electric utility grid interfacing. The research work investigates both stand-alone and grid connected renewable green-energy utilization schemes with a number of power electronic converter topologies and robust control schemes for both dispersed and hybrid renewable energy systems. Different sample study systems and control strategies are digitally simulated and fully validated using the MATLAB-Simulink-SimPower environment.

Aljankawey, Abdualah S.

262

Phase 1 of the First Solar Small Power System Experiment (experimental System No. 1). Volume 1: Technical Studies for Solar Point-focusing, Distributed Collector System, with Energy Conversion at the Collector, Category C  

NASA Technical Reports Server (NTRS)

The technical and economic feasibility of a solar electric power plant for a small community is evaluated and specific system designs for development and demonstration are selected. All systems investigated are defined as point focusing, distributed receiver concepts, with energy conversion at the collector. The preferred system is comprised of multiple parabolic dish concentrators employing Stirling cycle engines for power conversion. The engine, AC generator, cavity receiver, and integral sodium pool boiler/heat transport system are combined in a single package and mounted at the focus of each concentrator. The output of each concentrator is collected by a conventional electrical distribution system which permits grid-connected or stand-alone operation, depending on the storage system selected.

Clark, T. B. (editor)

1979-01-01

263

System and Battery Charge Control for PV-Powered AC Lighting Systems  

SciTech Connect

This report reviews a number of issues specific to stand-alone AC lighting systems. A review of AC lighting technology is presented, which discusses the advantages and disadvantages of various lamps. The best lamps for small lighting systems are compact fluorescent. The best lamps for intermediate-size systems are high- or low-pressure sodium. Specifications for battery charging and load control are provided with the goal of achieving lamp lifetimes on the order of 16,000 to 24,000 hours and battery lifetimes of 4 to 5 years. A rough estimate of the potential domestic and global markets for stand-alone AC lighting systems is presented. DC current injection tests were performed on high-pressure sodium lamps and the test results are presented. Finally, a prototype system was designed and a prototype system controller (with battery charger and DC/AC inverter) was developed and built.

Kern, G.

1999-04-01

264

Description of photovoltaic village power systems in the United States and Africa  

NASA Technical Reports Server (NTRS)

Photovoltaic power systems in remote villages in the United States and Africa are described. These projects were undertaken to demonstrate that existing photovoltaic system technology is capable of providing electrical power for basic domestic services for the millions of small, remote communities in both developed and developing countries. One system is located in the Papago Indian Village of Schuchuli in southwest Arizona (U. S.) and became operational 16 December 1978. The other system is located in Tangaye, a rural village in Upper Volta, Africa. It became operational 1 March 1979. The Schuchuli system has a 3.5 kW (peak) solar array which provides electric power for village water pumping, a refrigerator for each family, lights in the village buildings, and a community washing machine and sewing machine. The 1.8 kW (peak) Tangaye system provides power for community water pumping, flour milling and lights in the milling building. These are both stand-alone systems (i.e., no back-up power source) which are being operated and maintained by local personnel. Both systems are instrumented. Systems operations are being monitored by NASA to measure design adequacy and to refine designs for future systems.

Ratajczak, A. F.; Bifano, W. J.

1979-01-01

265

Economic assessment of advanced central-receiver solar-thermal power systems  

Microsoft Academic Search

The value and potential electric utility impact of several advanced central receiver solar thermal plant concepts in the role of electric generating stations were estimated. The impact of interest included economics, the cost of producing electricity, fuels displaced, and utility system reliability. The central receiver plants evaluated included solar\\/fossil hybrid concepts and solar stand alone plants with thermal storage. Liquid

J. T. Day; R. F. Boyle; M. J. Malone; D. W. Doar; W. G. Parker

1980-01-01

266

Power management system  

DOEpatents

A method of managing power resources for an electrical system of a vehicle may include identifying enabled power sources from among a plurality of power sources in electrical communication with the electrical system and calculating a threshold power value for the enabled power sources. A total power load placed on the electrical system by one or more power consumers may be measured. If the total power load exceeds the threshold power value, then a determination may be made as to whether one or more additional power sources is available from among the plurality of power sources. At least one of the one or more additional power sources may be enabled, if available.

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

2007-10-02

267

Control System for a Diesel Generator and UPS Based Microgrid  

NASA Astrophysics Data System (ADS)

In this paper a microgrid composed of a diesel generator and two uninterruptible power supply systems with separate battery banks is introduced. The microgrid located in three academic buildings of Tallinn University of Technology. A three-level control and monitoring system for the microgrid based on the EtherNet/IP communication network is developed. In addition, a control strategy of the microgrid in the grid-connected and stand-alone mode of operation is proposed.

Palamar, Andriy; Pettai, Elmo; Beldjajev, Viktor

2010-01-01

268

Dynamic modeling of a photovoltaic hydrogen fuel cell hybrid system  

Microsoft Academic Search

The objective of this paper is to mathematically model a stand-alone renewable power system, referred to as “Photovoltaic–Fuel Cell (PVFC) hybrid system”, which maximizes the use of a renewable energy source. It comprises a photovoltaic generator (PV), a water electrolyzer, a hydrogen tank, and a proton exchange membrane (PEM) fuel cell generator. A multi-domain simulation platform Simplorer is employed to

J. J. Hwang; L. K. Lai; W. Wu; W. R. Chang

2009-01-01

269

An Overview of Power Electronics Applications in Fuel Cell Systems: DC and AC Converters  

PubMed Central

Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter. PMID:25478581

Ali, M. S.; Kamarudin, S. K.; Masdar, M. S.; Mohamed, A.

2014-01-01

270

An overview of power electronics applications in fuel cell systems: DC and AC converters.  

PubMed

Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter. PMID:25478581

Ali, M S; Kamarudin, S K; Masdar, M S; Mohamed, A

2014-01-01

271

Development of a Multi-bus, Multi-source Reconfigurable Stirling Radioisotope Power System Test Bed  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) has typically used Radioisotope Thermoelectric Generators (RTG) as their source of electric power for deep space missions. A more efficient and potentially more cost effective alternative to the RTG, the high efficiency 110 watt Stirling Radioisotope Generator 110 (SRG110) is being developed by the Department of Energy (DOE), Lockheed Martin (LM), Stirling Technology Company (STC) and NASA Glenn Research Center (GRC). The SRG110 consists of two Stirling convertors (Stirling Engine and Linear Alternator) in a dual-opposed configuration, and two General Purpose Heat Source (GPHS) modules. Although Stirling convertors have been successfully operated as a power source for the utility grid and as a stand-alone portable generator, demonstration of the technology required to interconnect two Stirling convertors for a spacecraft power system has not been attempted. NASA GRC is developing a Power System Test Bed (PSTB) to evaluate the performance of a Stirling convertor in an integrated electrical power system application. This paper will describe the status of the PSTB and on-going activities pertaining to the PSTB in the NASA Thermal-Energy Conversion Branch of the Power and On-Board Propulsion Technology Division.

Coleman, Anthony S.

2004-01-01

272

Electrification with solar powered mini-grids, a case study for the island of Kythnos  

Microsoft Academic Search

A study was prepared regarding the viability and potential of electrifying remote houses and settlements with stand alone PV systems in remote areas. The financial and technical factors that affect the implementation of stand alone PV systems in the Greek islands, and particularly for the island of Kythnos, are presented. The patterns of energy consumption of the users electrified by

S. Tselepis

2003-01-01

273

Surgical Outcome of a Zero-profile Device Comparing with Stand-alone Cage and Anterior Cervical Plate with Iliac Bone Graft in the Anterior Cervical Discectomy and Fusion  

PubMed Central

Objective A Zero-profile device is a cervical stand-alone cage with integrated segmental fixation device. We characteristically evaluated the radiological changes as well as clinical outcomes in the application of Zero-profile devices compared with stand-alone cages and anterior cervical plates with iliac bone grafts for the cervical disease. Methods Retrospectively, total 60 patients at least more than one year follow-up were enrolled. Twenty patients were treated with Zero-profile devices (Group A), twenty patients with stand-alone cages (Group B) and twenty patients with anterior cervical plates and iliac bone grafts (Group C) for a single level cervical disease. The clinical outcomes were evaluated by Odom's criteria and Bazaz-Yoo dysphagia index. The radiologic parameters were by subsidence and the changes of the midpoint interbody height (IBH), the segmental kyphotic angle (SKA), the overall kyphotic angle (OKA) in index level. Results Although there was no significant clinical difference according to the Odom's criteria among them(p=0.766), post-operative dysphagia was significantly decreased in the Group A and B compared with the Group C (p=0.04). From the immediate postoperative to the last follow-up time, the mean change of IBH decrement and SKA increment were significant in the Group B compared with the Group A (p=0.025, p=0.033) and the Group C (p=0.001, p=0.000). The subsidence rate was not significant among all groups (p=0.338). Conclusion This Zero-profile device is a valuable alternative to the anterior cervical discectomy and fusion with a low incidence of postoperative dysphagia and without segmental kyphotic change. PMID:25346764

Shin, Jae Sik; Cho, Pyoung Goo

2014-01-01

274

A Modular Plasma System Combining Ion Thrusters, Inertial Electrostatic Confinement, and Theta Pinch Devices  

Microsoft Academic Search

This system is designed to improve the effectiveness and investigate the synergy between several types of ion thrusters and fusion devices, which have typically been used as stand-alone systems. The experimental apparatus is powered by a 45kV capacitor bank, which can be discharged simultaneously through 2 separate cylindrical copper theta pinch coils. In addition 60kV can be applied to the

Jeffrey E. Norman; David N. Ruzic

1999-01-01

275

The FAST-AIMS Clinical Mass Spectrometry Analysis System  

PubMed Central

Within clinical proteomics, mass spectrometry analysis of biological samples is emerging as an important high-throughput technology, capable of producing powerful diagnostic and prognostic models and identifying important disease biomarkers. As interest in this area grows, and the number of such proteomics datasets continues to increase, the need has developed for efficient, comprehensive, reproducible methods of mass spectrometry data analysis by both experts and nonexperts. We have designed and implemented a stand-alone software system, FAST-AIMS, which seeks to meet this need through automation of data preprocessing, feature selection, classification model generation, and performance estimation. FAST-AIMS is an efficient and user-friendly stand-alone software for predictive analysis of mass spectrometry data. The present resource review paper will describe the features and use of the FAST-AIMS system. The system is freely available for download for noncommercial use. PMID:19956420

Fananapazir, Nafeh; Statnikov, Alexander; Aliferis, Constantin F.

2009-01-01

276

Stand-alone groundwater desalination system using reverse osmosis combined with a cooled greenhouse for use in arid and semi-arid zones of India  

Microsoft Academic Search

In many areas of northern India, salinity renders groundwater unsuitable for drinking and even for irrigation. Though membrane treatment can be used to remove the salt, there are some drawbacks to this approach e.g. (1) depletion of the groundwater due to over-abstraction, (2) saline contamination of surface water and soil caused by concentrate disposal and (3) high electricity usage. To

P. A. Davies; A. K. Hossain; P. Vasudevan

2009-01-01

277

Solar powered desalination system  

E-print Network

of fresh water? Table 1.19: Solar Desalination Systemssolar desalination systems with a variety of power sources, desalination processes, and fresh watersolar-powered reverse osmosis system can be taken to a fresh water

Mateo, Tiffany Alisa

2011-01-01

278

DSN Monitor and Control System, Mark III-80  

NASA Technical Reports Server (NTRS)

The Deep Space Network monitor and control system, Mark III-80 is described. The major implementations required to evolve from the Mark III-78 to the Mark III-80 configuration are identified. The affected facilities are the deep space stations and the network operations control center (NOCC). At the deep space stations a stand-alone host processor is implemented. Included are software (host software) changes which provide downline loading to the stand-alone host processor from a disc unit of any idle data system computer. At deep space stations with a 34 m antenna, the microwave subsystem is provided with an interface which allows remote configuration selection at the central monitor and control operator's position. In the NOCC, software changes are implemented to provide precision power monitor and GCF monitor displays.

Leflang, J. G.

1980-01-01

279

Performance characteristics of solar-photovoltaic flywheel-storage systems  

NASA Astrophysics Data System (ADS)

A solar photovoltaic energy flywheel storage and conversion system for residential applications was tested. Performance and efficiency measurements were conducted on the system, which utilizes low loss magnetic bearings, maximum power point tracking of the photovoltaic array, integrated permanent magnet motor generator, and output power conditioning sections of either the stand alone cycloconverter or utility interactive inverter type. The overall in/out electrical storage efficiency of the flywheel system was measured along with the power transfer efficiencies of the individual components and the system spin down tare losses. The system compares favorably with systems which use batteries and inverters.

Jarvinen, P. O.; Brench, B. L.; Rasmussen, N. E.

280

A knowledge-based approach to the design of integrated renewable energy systems  

Microsoft Academic Search

Integrated renewable systems utilize two or more renewable energy resources and end-use technologies to supply a variety of energy needs, often in a stand-alone mode. A knowledge-based design approach that minimizes the total capital cost at a preselected reliability level is presented. The reliability level is quantified by the loss of power supply probability. The procedure includes some resource-need matching

R. Ramakumar; I. Abouzahr; K. Ashenayi

1992-01-01

281

Designing cost-effective seawater reverse osmosis system under optimal energy options  

Microsoft Academic Search

Today, three billion people around the world have no access to clean drinking water and about 1.76 billion people live in areas already facing a high degree of water stress. This paper analyzes the cost-effectiveness of a stand alone small-scale renewable energy-powered seawater reverse osmosis (SWRO) system for developing countries. In this paper, we have introduced a new methodology; an

Asmerom M. Gilau; Mitchell J. Small

2008-01-01

282

Design, fabrication, and certification of advanced modular PV power systems. Final technical progress report  

SciTech Connect

Solar Electric Specialties Company (SES) has completed a two and a half year effort under the auspices of the US Department of Energy (DOE) PVMaT (Photovoltaic Manufacturing Technology) project. Under Phase 4A1 of the project for Product Driven System and Component Technology, the SES contract ``Design, Fabrication and Certification of Advanced Modular PV Power Systems`` had the goal to reduce installed system life cycle costs through development of certified (Underwriters Laboratories or other listing) and standardized prototype products for two of the product lines, MAPPS{trademark} (Modular Autonomous PV Power Supply) and Photogensets{trademark}. MAPPS are small DC systems consisting of Photovoltaic modules, batteries and a charge controller and producing up to about a thousand watt-hours per day. Photogensets are stand-alone AC systems incorporating a generator as backup for the PV in addition to a DC-AC inverter and battery charger. The program tasks for the two-year contract consisted of designing and fabricating prototypes of both a MAPPS and a Photogenset to meet agency listing requirements using modular concepts that would support development of families of products, submitting the prototypes for listing, and performing functionality testing at Sandia and NREL. Both prototypes were candidates for UL (Underwriters Laboratories) listing. The MAPPS was also a candidate for FM (Factory Mutual) approval for hazardous (incendiary gases) locations.

Lambarski, T.; Minyard, G. [Solar Electric Specialties Co., Willits, CA (United States)

1998-10-01

283

[Application of a stand-alone interbody fusion cage based on a novel porous TiO2/glass ceramic--2: Biomechanical evaluation after implantation in the sheep cervical spine].  

PubMed

Animals are becoming more and more common as in vivo models for the human spine. Especially the sheep cervical spine is stated to be of good comparability and usefulness in the evaluation of in vivo radiological, biomechanical and histological behaviour of new bone replacement materials, implants and cages for cervical spine interbody fusion. In preceding biomechanical in vitro examinations human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO2/glass composite (Ecopore) or polymethylmethacrylate (PMMA) after discectomy. Following our first experience with the use of the new material and its influence on the primary stability after in vitro application we carried out fusions of 20 sheep cervical spines levels with either PMMA or an Ecopore-cage, and performed radiological examinations during the following 2-4 months. In this second part of the study we intended the biomechanical evaluation of the spine segments with reference to the previously determined morphological findings, like subsidence of the implants, significant increase of the kyphosis angle and degree of the bony fusion along with the interpretation of the results. 20 sheep cervical spines segments with either PMMA- or Ecopore-fusion in the levels C2/3 and C4/5 were tested, in comparison to 10 native corresponding sheep cervical spine segments. Non-destructive biomechanical testing was performed, including flexion/extension, lateral bending and axial rotation using a spine testing apparatus. Three-dimensional range of motion (ROM) was evaluated using an ultrasound measurement system. In the native spine segments C2/3 and C4/5 the ROM increased in cranio-caudal direction particulary in flexion/extension, less pronounced in lateral flexion and axial rotation (p < 0.05). The overall ROM of both tested segments was greatest in lateral flexion, reduced to 52% in flexion/extension and to 16% in axial rotation. After 2 months C2/3- and C4/5-segments with PMMA-fusion and C2/3-segments with Ecopore-interposition showed decrease of ROM in lateral flexion in comparison to the native segments, indicating increasing stiffening. However, after 4 months all operated segments, independent from level or implanted material, were stiffer than the comparable native segments. The decrease of the ROM correlated with the radiological-morphological degree of fusion. Our evaluation of the new porous TiO2/glass composite as interbody fusion cage has shown satisfactory radiological results as well as distinct biomechanical stability and fusion of the segments after 4 months in comparison to PMMA. After histological analysis of the bone-biomaterial-interface, further examinations of this biomaterial previous to an application as alternative to other customary cages in humans are necessary. PMID:15884708

Korinth, M C; Hero, T; Pandorf, T; Zell, D

2005-04-01

284

Cogeneration power systems  

NASA Technical Reports Server (NTRS)

Cogeneration is defined as the combination of electrical generation and process heat for more efficient use of fuel. Comparisons of energy utilization in conventional electric power plants and cogeneration electric power plants are presented. Characteristics of various cogeneration systems are also presented. Systems are analyzed for use in utility systems and industrial systems. Economic and cost analysis are reviewed.

Davis, H. S.

1978-01-01

285

Space station power system  

NASA Technical Reports Server (NTRS)

The major requirements and guidelines that affect the space station configuration and power system are explained. The evolution of the space station power system from the NASA program development-feasibility phase through the current preliminary design phase is described. Several early station concepts are described and linked to the present concept. Trade study selections of photovoltaic system technologies are described in detail. A summary of present solar dynamic and power management and distribution systems is also given.

Baraona, Cosmo R.

1987-01-01

286

Advanced photovoltaic power systems  

NASA Astrophysics Data System (ADS)

The state-of-the-art of synchronous orbit photovoltaic power systems is characterized including performance of solar arrays, batteries and power control components. Advanced developments in each of these areas are reviewed and projections are made for performance improvements in the 1980-1985 time period. It is estimated that overall photovoltaic power system specific weight could decrease from a present value of 126 kg/kW to approximately 43 kg/kW in 1985. These performance predictions are compared to projections of nuclear system performance over the same period. The analysis indicates that advanced photovoltaic power systems will exhibit specific weights which are lower than isotope and reactor nuclear systems at all power levels up to approximately 25 kW. At higher power levels, higher energy density batteries would be required to compete with the projected performance of advanced nuclear systems.

Goldsmith, P.; Reppucci, G. M.

1977-03-01

287

Stand-alone anchored cage versus cage with plating for single-level anterior cervical discectomy and fusion: a prospective, randomized, controlled study with a 2-year follow-up.  

PubMed

To avoid complications associated with plating in anterior cervical discectomy and fusion (ACDF), stand-alone anchored PEEK cage was developed and favourable outcomes with a low rate of dysphasia have been described. The objective of this study was to compare the clinical and radiological outcomes of ACDF using a standalone anchored PEEK cage (PREVAIL; Medtronic Sofamor Danek, Memphis, TN) with those of a PEEK cage with plating in a prospective randomized manner. Fifty patients with single-level cervical radiculopathy were randomly assigned to a PREVAIL or a PEEK cage with plating. Following 3, 6, 12, and 24 months, clinical and radiological outcomes were assessed. The mean surgical time for the patients with a PREVAIL was significantly shorter than that for those with a PEEK cage with plating. The clinical outcomes evaluated by visual analogue scale for pain and the Odom's criteria were comparable between both the groups. Both the groups demonstrated the high fusion rate (92 % in PREVAIL; 96 % in PEEK cage with plating). The subsidence rate and the improvement of cervical alignment were comparable between both the groups. The incidence of adjacent-level ossification was significantly lower for patients with a PREVAIL than that for those with a PEEK cage with plating. The rate of dysphasia graded by the method of Bazaz and measurement of prevertebral soft tissue swelling indicated no significant differences between both the groups. Our prospective randomized study confirmed that stand-alone anchored PEEK cage is a valid alternative to plating in ACDF with a low rate of adjacent-level ossification. However, the potential to reduce the incidence of dysphasia was not confirmed. PMID:25283362

Nemoto, Osamu; Kitada, Akira; Naitou, Satoko; Tachibana, Atsuko; Ito, Yuya; Fujikawa, Akira

2014-10-01

288

Economical space power systems  

NASA Astrophysics Data System (ADS)

A commercial approach to design and fabrication of an economical space power system is investigated. Cost projections are based on a 2 kW space power system conceptual design taking into consideration the capability for serviceability, constraints of operation in space, and commercial production engineering approaches. A breakdown of the system design, documentation, fabrication, and reliability and quality assurance estimated costs are detailed.

Burkholder, J. H.

1980-01-01

289

Market assessment of photovoltaic power systems for agricultural applications in Morocco  

NASA Astrophysics Data System (ADS)

Results of a month-long study in Morocco aimed at assessing the market potential for stand-alone photovoltaic systems in agriculture and rural service applications are presented. The following applications, requiring less than 15 kW of power, are described: irrigation, cattle watering, refrigeration, crop processing, potable water and educational TV. Telecommunications and transportation signalling applications, descriptions of power and energy use profiles, assessments of business environment, government and private sector attitudes towards photovoltaics, and financing were also considered. The Moroccan market presents both advantages and disadvantages for American PV manufacturers. The principle advantages of the Moroccan market are: a limited grid, interest in and present use of PV in communications applications, attractive investment incentives, and a stated policy favoring American investment. Disadvantages include: lack of government incentives for PV use, general unfamiliarity with PV technology, high first cost of PV, a well-established market network for diesel generators, and difficulty with financing. The market for PV in Morocco (1981-1986), will be relatively small, about 340 kwp. The market for PV is likely to be more favorable in telecommunications, transport signalling and some rural services. The primary market appears to be in the public (i.e., government) rather than private sector, due to financial constraints and the high price of PV relative to conventional power sector.

Steingass, H.; Asmon, I.

1981-09-01

290

Market assessment of photovoltaic power systems for agricultural applications in Morocco  

NASA Technical Reports Server (NTRS)

Results of a month-long study in Morocco aimed at assessing the market potential for stand-alone photovoltaic systems in agriculture and rural service applications are presented. The following applications, requiring less than 15 kW of power, are described: irrigation, cattle watering, refrigeration, crop processing, potable water and educational TV. Telecommunications and transportation signalling applications, descriptions of power and energy use profiles, assessments of business environment, government and private sector attitudes towards photovoltaics, and financing were also considered. The Moroccan market presents both advantages and disadvantages for American PV manufacturers. The principle advantages of the Moroccan market are: a limited grid, interest in and present use of PV in communications applications, attractive investment incentives, and a stated policy favoring American investment. Disadvantages include: lack of government incentives for PV use, general unfamiliarity with PV technology, high first cost of PV, a well-established market network for diesel generators, and difficulty with financing. The market for PV in Morocco (1981-1986), will be relatively small, about 340 kwp. The market for PV is likely to be more favorable in telecommunications, transport signalling and some rural services. The primary market appears to be in the public (i.e., government) rather than private sector, due to financial constraints and the high price of PV relative to conventional power sector.

Steingass, H.; Asmon, I.

1981-01-01

291

Power system commonality study  

NASA Astrophysics Data System (ADS)

A limited top level study was completed to determine the commonality of power system/subsystem concepts within potential lunar and Mars surface power system architectures. A list of power system concepts with high commonality was developed which can be used to synthesize power system architectures which minimize development cost. Examples of potential high commonality power system architectures are given in this report along with a mass comparison. Other criteria such as life cycle cost (which includes transportation cost), reliability, safety, risk, and operability should be used in future, more detailed studies to select optimum power system architectures. Nineteen potential power system concepts were identified and evaluated for planetary surface applications including photovoltaic arrays with energy storage, isotope, and nuclear power systems. A top level environmental factors study was completed to assess environmental impacts on the identified power system concepts for both lunar and Mars applications. Potential power system design solutions for commonality between Mars and lunar applications were identified. Isotope, photovoltaic array (PVA), regenerative fuel cell (RFC), stainless steel liquid-metal cooled reactors (less than 1033 K maximum) with dynamic converters, and in-core thermionic reactor systems were found suitable for both lunar and Mars environments. The use of SP-100 thermoelectric (TE) and SP-100 dynamic power systems in a vacuum enclosure may also be possible for Mars applications although several issues need to be investigated further (potential single point failure of enclosure, mass penalty of enclosure and active pumping system, additional installation time and complexity). There are also technical issues involved with development of thermionic reactors (life, serviceability, and adaptability to other power conversion units). Additional studies are required to determine the optimum reactor concept for Mars applications. Various screening criteria (availability, environmental compatibility, mass competitiveness of energy storage, safety, and practicality for the application) were used to define concept applicability for each lunar and Mars application. A screening study resulted in 13 power systems for lunar applications and 15 for Mars applications. A commonality analysis showed several power systems with potentially high commonality (across both lunar and Mars applications). These high commonality systems include d PVA/RFC, dynamic isotope (1033 K Stirling, 1133 K Brayton, and 1300 K Brayton PCU's), SP-100 TE and dynamic derivatives (Mars systems required vacuum enclosure), in-core thermionic reactor, and liquid metal cooled reactor/Stirling cycle (1033 K). The generic commonality results were used to synthesize 3 high commonality power system architectures: (1) predominantly PV (limited nuclear and isotope), (2) predominantly in-core thermionic reactor/DIPS, and (3) predominantly SP-100 reactor/DIPS. The in-core thermionic reactor/DIPS power system architecture had the lowest total mass. Specific outputs from this study included lists of power system requirements, power system candidates, a power system application matrix, power system characteristics (mass), power system commonality ratings, example high commonality power system architectures, architecture masses, and issues/design solutions for lunar/Mars commonality.

Littman, Franklin D.

1992-07-01

292

Space Nuclear Power Systems  

NASA Technical Reports Server (NTRS)

Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

Houts, Michael G.

2012-01-01

293

Personal power systems  

Microsoft Academic Search

The lack of compact, efficient, human compatible, lightweight power sources impedes the realization of machine-enhanced human endeavor. Electronic and communication devices, as well as mobile robotic devices, need new power sources that will allow them to operate autonomously for periods of hours. In this work, a personal power system implies an application of interest to an individual person. The human-compatible

Derek Dunn-Rankin; Elisângela Martins Leal; David C. Walther

2005-01-01

294

Power systems (review of \\  

Microsoft Academic Search

This book covers a variety of issues related to the integration and operation of renewable energy (RE) in power systems. Given the steady increase in demand for electricity, increased interest in protecting the environment and deployment of RE power generation sources, and their increased penetration into the power grid worldwide, the subject book is very timely. Congratulations to the authors!

Hashem Nehrir

2009-01-01

295

Solar powered desalination system  

E-print Network

solar power more efficient and cost effective. Figure 1.13: Californiasolar power is not yet cost competitive to fossil fuel. In California,California 2008 Total System Generation…………………………………..32 Table 1.18: Largest PV Power Plants……………………………………………………32 Table 1.19: Solar

Mateo, Tiffany Alisa

2011-01-01

296

Electrical power generating system  

NASA Technical Reports Server (NTRS)

A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced.

Nola, F. J. (inventor)

1983-01-01

297

MODULAR BAYESIAN INFERENCE AND LEARNING OF DECISION NETWORKS AS STAND-ALONE MECHANISMS OF THE MABEL MODEL: IMPLICATIONS FOR VISUALIZATION, COMPREHENSION, AND POLICY MAKING  

Microsoft Academic Search

This paper describes a modular component of the MABEL model agents' cognitive inference mechanism. The probabilistic and probabilogic representation of the agents' environment and state space is coupled with a Bayesian belief and decision network functionality, which in fact holds Markovian semiparametric properties. Different approaches to modeling multi-agent systems are described and analyzed; problem-, model-, and knowledge-driven approaches to agent

K. ALEXANDRIDIS; B. PIJANOWSKI

298

A Low Distortion PWM DC-AC Inverter, with Active Current and Voltage Control, Allowing Line-Interfaced and Stand-Alone Photovoltaic Applications  

Microsoft Academic Search

The energy transfer between a photovoltaic solar panel and the grid can be realized by means of a DC-AC inverter, which is described in this paper. A reliability study of the entire system (i.e. the solar panels and the inverter) shows that the voltage generated by the solar panel matrix has to be low (? 100 V). The stability conditions

1982-01-01

299

Crowd-powered systems  

E-print Network

Crowd-powered systems combine computation with human intelligence, drawn from large groups of people connecting and coordinating online. These hybrid systems enable applications and experiences that neither crowds nor ...

Bernstein, Michael Scott

2012-01-01

300

Laboratory evaluation of a pilot cell battery protection system for photovoltaic applications  

NASA Technical Reports Server (NTRS)

An energy storage method for the 3.5 kW battery power system was investigated. The Pilot Cell Battery Protection System was tested for use in photovoltaic power systems and results show that this is a viable method of storage battery control. The method of limiting battery depth of discharge has the following advantages: (1) temperature sensitivity; (2) rate sensitivity; and (3) state of charge indication. The pilot cell concept is of interest in remote stand alone photovoltaic power systems. The battery can be protected from damaging overdischarge by using the proper ratio of pilot cell capacities to main battery capacity.

Cataldo, R. L.; Thomas, R. D.

1981-01-01

301

Lunar solar-power system: Commerical power  

Microsoft Academic Search

The proposed Lunar Solar-Power (LSP) System collects solar power on the moon. The power is converted to beams of microwaves and transmitted to fields of microwave receivers (rectennas) on Earth that provide electric power to local and regional power grids. LSP can provide abundant and low cost energy to Earth to sustain several centuries of economic development on Earth and

David R. Criswell

1995-01-01

302

TROPIX power system architecture  

NASA Astrophysics Data System (ADS)

This document contains results obtained in the process of performing a power system definition study of the TROPIX power management and distribution system (PMAD). Requirements derived from the PMADs interaction with other spacecraft systems are discussed first. Since the design is dependent on the performance of the photovoltaics, there is a comprehensive discussion of the appropriate models for cells and arrays. A trade study of the array operating voltage and its effect on array bus mass is also presented. A system architecture is developed which makes use of a combination of high efficiency switching power convertors and analog regulators. Mass and volume estimates are presented for all subsystems.

Manner, David B.; Hickman, J. Mark

1995-09-01

303

TROPIX Power System Architecture  

NASA Technical Reports Server (NTRS)

This document contains results obtained in the process of performing a power system definition study of the TROPIX power management and distribution system (PMAD). Requirements derived from the PMADs interaction with other spacecraft systems are discussed first. Since the design is dependent on the performance of the photovoltaics, there is a comprehensive discussion of the appropriate models for cells and arrays. A trade study of the array operating voltage and its effect on array bus mass is also presented. A system architecture is developed which makes use of a combination of high efficiency switching power convertors and analog regulators. Mass and volume estimates are presented for all subsystems.

Manner, David B.; Hickman, J. Mark

1995-01-01

304

Power Systems Decentralized Optimization  

NASA Astrophysics Data System (ADS)

The paper's aim is to explore both active and reactive power losses minimization and voltage stability by a decentralized strategy. The approach assumes that the grid is split into sub-systems; each sub-system is in charge of its own optimal solution using equivalents for the neighbors, so that information exchange is not required. Schedule interchanges among sub-systems have been added as constraints into the optimal formulation. Once the individual solutions are available, the corresponding settings are allocated to the corresponding equipment and a full power flow study is carried out to assure the steady-state preservation. Results are exhibited on two test power systems.

Ramirez, Juan M.; Vargas-Marín, Javier; Correa-Gutiérrez, Rosa E.

2014-12-01

305

2012 International Symposium on Communications and Information Technologies (ISCIT) On a New Weighting Matrix to Enhance the Accuracy of Stand-Alone GNSS Positioning  

E-print Network

Abstract — This paper focuses on location accuracy enhancement and performance comparison for global navigation satellite systems (GNSS) based positioning in light multipath propagation environments. The well-known linear iterative least-squares (LS) estimator algorithm performs the location of a ground (mobile) terminal. A sliding window and subspace decomposition (SD) based approach is proposed to generate coefficients for weighting the pseudorange measurements between the ground receiver and a set of satellites. Simulation results with real pseudorange measurement data (recorded at two different scenarios) demonstrate that the proposed SD-based LS algorithm significantly outperforms the existing LS algorithm, with root mean square error (RMSE) reduced by more than 0.7m. Keywords-GNSS; satellite positioning; subspace decomposition; least-squares; I.

Kegen Yu

306

Autonomous power expert system  

NASA Technical Reports Server (NTRS)

The goal of the Autonomous Power System (APS) program is to develop and apply intelligent problem solving and control technologies to the Space Station Freedom Electrical Power Systems (SSF/EPS). The objectives of the program are to establish artificial intelligence/expert system technology paths, to create knowledge based tools with advanced human-operator interfaces, and to integrate and interface knowledge-based and conventional control schemes. This program is being developed at the NASA-Lewis. The APS Brassboard represents a subset of a 20 KHz Space Station Power Management And Distribution (PMAD) testbed. A distributed control scheme is used to manage multiple levels of computers and switchgear. The brassboard is comprised of a set of intelligent switchgear used to effectively switch power from the sources to the loads. The Autonomous Power Expert System (APEX) portion of the APS program integrates a knowledge based fault diagnostic system, a power resource scheduler, and an interface to the APS Brassboard. The system includes knowledge bases for system diagnostics, fault detection and isolation, and recommended actions. The scheduler autonomously assigns start times to the attached loads based on temporal and power constraints. The scheduler is able to work in a near real time environment for both scheduling and dynamic replanning.

Ringer, Mark J.; Quinn, Todd M.

1990-01-01

307

Power Systems Control Architecture  

SciTech Connect

A diagram provided in the report depicts the complexity of the power systems control architecture used by the national power structure. It shows the structural hierarchy and the relationship of the each system to those other systems interconnected to it. Each of these levels provides a different focus for vulnerability testing and has its own weaknesses. In evaluating each level, of prime concern is what vulnerabilities exist that provide a path into the system, either to cause the system to malfunction or to take control of a field device. An additional vulnerability to consider is can the system be compromised in such a manner that the attacker can obtain critical information about the system and the portion of the national power structure that it controls.

James Davidson

2005-01-01

308

Effect of Initial Powder Morphology and Thermal and Mechanical Properties of Stand-Alone Plasma-Sprayed 7 wt%Y2O3-ZrO2 Coatings  

SciTech Connect

The effects of starting powder morphology on the thermal and mechanical properties of stand-alone plasma-sprayed 7 wt.% Y{sub 2}O{sub 3}-ZrO{sub 2}(YSZ) coatings were studied. Two powder morphologies were investigated: an agglomerated and sintered powder (referred to presently as 'AS') and a powder manufactured using plasma spheroidization to create hollow spheres (referred to presently as 'HS'). Coatings made from AS powders contained 0.21 wt.% SiO{sub 2} impurity, twice as much as observed in coatings made from HS powders. Properties of coatings made from each powder type were compared in the as-sprayed state and after 50 h heat treatments at temperatures ranging from 1000 to 1400 C. SEM microstructural investigations revealed significant differences in the porosity and distribution of pores in the coatings. In coatings made with AS powders the majority of the high aspect ratio pores were located between lamella (interlamellar porosity). In addition to interlamellar pores, coatings made with HS powders demonstrated 1.5 times more spherical-shaped globular pores by number located within lamella. Globular pores were shown to still exist in coatings made with HS powders after 50 h heat treatments at 1400 C. Archimedes porosity measurements showed that coatings made with AS powders typically contained 4-5% less total porosity than coatings made with HS powders. Thermal conductivity experiments using laser flash showed that there was no difference in the thermal conductivity of coatings made from either powder type in the as-sprayed state despite higher porosity in the coatings made from HS powders. After a 50 h heat treatment at 1000 and 1200 C, coatings made from both powder types still demonstrated statistically similar thermal conductivities. However, after a 50 h heat treatment at 1400 C the thermal conductivity of coatings made from AS powders was found to be 0.3 W/m/K higher than coatings made from HS powders. Microstructural differences in the coatings made from the two powder types that affected sintering rates, including the increased level of SiO{sub 2} impurities and fewer globular pores, were used to explain variations in properties. In uniaxial compression tests on stand-alone samples at 1000, 1100, and 1200 C, coatings made from AS powders typically relaxed more stress than coatings made from HS powders. Differences in coating relaxation became more apparent as the test temperature increased through 1200 C. The higher percentage of impurity SiO{sub 2} in the AS coatings is believed to contribute to increased relaxation via formation of a glassy phase at the grain boundaries which assists grain boundary sliding during elevated temperature deformation.

Ercan, Batur [ORNL; Bowman, Keith [ORNL; Trice, Rodney [ORNL; Wang, Hsin [ORNL; Porter, Wallace D [ORNL

2006-01-01

309

Chapter 2: Stand-alone Applications - TOPCAT  

Microsoft Academic Search

Tool for OPerations on Catalogues And Tables or TOPCAT is a graphical viewer for table data. It offers a variety of ways to work with data tables, including a browser for the cell data, viewers for information about table and column metadata, dataset visualization, and even analysis. We discuss a small subset of TOPCAT's functionalities in this chapter. TOPCAT was

C. J. Miller

2007-01-01

310

Chapter 2: Stand-alone Applications - TOPCAT  

NASA Astrophysics Data System (ADS)

Tool for OPerations on Catalogues And Tables or TOPCAT is a graphical viewer for table data. It offers a variety of ways to work with data tables, including a browser for the cell data, viewers for information about table and column metadata, dataset visualization, and even analysis. We discuss a small subset of TOPCAT's functionalities in this chapter. TOPCAT was originally developed as part of the Starlink program in the United Kingdom. It is now maintained by AstroGrid. The program is written in pure Java and available under the GNU General Public License. It is available for download and a version is included in the software distribution accompanying this book. TOPCAT is a GUI interface on top of the STIL library. A command line interface to this library, STILTS, described in Chapter 21 provides scriptable access to many of the capabilities described here. The purpose of this tutorial is to provide an overview of TOPCAT to the novice user. The best place to look for and learn about TOPCAT is the web page maintained by Mark B. Taylor. There, TOPCAT documentation is provided in HTML, PDF, via screen shots, etc. In this chapter we take the user through a few examples that give the general idea of how TOPCAT works. The majority of the functionality of TOPCAT is not included in this short tutorial. Our goal in this tutorial is to lead the reader through an exercise that would result in a publication quality figure (e.g. for a journal article). Specifically, we will use TOPCAT to show how the color-magnitude relation of a galaxy cluster compares to that of all galaxies in the Sloan Digital Sky Survey (York et al. 2000). This diagnostic is used not only in cluster finding, but its linear fit can provide insight into the age and/or metallicity of the oldest galaxies in galaxy clusters (which are some of the oldest galaxies in the Universe). The data we need for this exercise are: 1) the entire spectroscopic galaxy catalog from the SDSS, with galaxy positions, galaxy redshifts, and galaxy magnitudes and 2) galaxy members of a known galaxy cluster. For the former, we will download data directly from the SDSS servers to our local machine for analysis. For the latter, we will use TOPCAT's ability to call live cone search services.

Miller, C. J.

311

Stand alone biofuel production from algae  

Microsoft Academic Search

In this feature, leading researchers in the field of microbial biotechnology speculate on the technical and conceptual developments that will drive innovative research and open new vistas over the next few years

R. H. Wijffels; M. G. J. Janssen; M. J. Barbosa

2011-01-01

312

A Stand-Alone Interactive Physics Showcase  

ERIC Educational Resources Information Center

We present a showcase with interactive exhibits of basic physical experiments that constitutes a complementary method for teaching physics and interesting students in physical phenomena. Our interactive physics showcase, shown in Fig. 1, stimulates interest for science by letting the students experience, firsthand, surprising phenomena and…

Pfaff, Daniel; Hagelgans, Anja; Weidemuller, Matthias; Bretzer, Klaus

2012-01-01

313

Evolution of a Medical School Library Circulation System from a Batch to an Online System  

PubMed Central

The circulation system at the Health Sciences Library, George Washington University Medical Center has evolved from a stand alone batch process to an online system which is integrated into an automated library system called HAL (Himmelfarb Automated Library-System).

Larson, Robert H.

1982-01-01

314

Modeling and sizing optimization of hybrid photovoltaic/wind power generation system  

NASA Astrophysics Data System (ADS)

The rapid industrialization and growth of world's human population have resulted in the unprecedented increase in the demand for energy and in particular electricity. Depletion of fossil fuels and impacts of global warming caused widespread attention using renewable energy sources, especially wind and solar energies. Energy security under varying weather conditions and the corresponding system cost are the two major issues in designing hybrid power generation systems. In this paper, the match evaluation method (MEM) is developed based on renewable energy supply/demand match evaluation criteria to size the proposed system in lowest cost. This work is undertaken with triple objective function: inequality coefficient, correlation coefficient, and annualized cost of system. It provides optimum capacity of as many numbers of supplies as required to match with a load demand in lowest investment, so it can handle large-scale design problems. Meteorological data were collected from the city of Zabol, located in south-east of Iran, as a case study. Six types of wind turbine and also six types of PV modules, with different output powers and costs, are considered for this optimization procedure. A battery storage system is used to even out irregularities in meteorological data. A multi-objective particle swarm optimization algorithm has been used for the prediction of an optimized set of design based on the MEM technique. The results of this study are valuable for evaluating the performance of future stand-alone hybrid power system. It is worth mentioning that the proposed methodology can be effectively employed for any composition of hybrid energy systems in any locations taking into account the meteorological data and the consumer's demand.

Yazdanpanah, Mohammad-Ali

2014-03-01

315

Solar total energy project at Shenandoah, Georgia system design  

NASA Astrophysics Data System (ADS)

The solar total energy system (STES) was to provide 50% of the total electrical and thermal energy requirements of the 25,000 sq ft Bleyle of America knitwear plant located at the Shenandoah Site. The system will provide 400 kilowatts electrical and 3 megawatts of thermal energy. The STES has a classical, cascaded total energy system configuration. It utilizes one hundred twenty (120), parabolic dish collectors, high temperature (750 F) trickle oil thermal energy storage and a steam turbine generator. The electrical load shaving system was designed for interconnected operation with the Georgia Power system and for operation in a stand alone mode.

Poche, A. J.

1980-05-01

316

Automated Power-Distribution System  

NASA Technical Reports Server (NTRS)

Autonomous power-distribution system includes power-control equipment and automation equipment. System automatically schedules connection of power to loads and reconfigures itself when it detects fault. Potential terrestrial applications include optimization of consumption of power in homes, power supplies for autonomous land vehicles and vessels, and power supplies for automated industrial processes.

Ashworth, Barry; Riedesel, Joel; Myers, Chris; Miller, William; Jones, Ellen F.; Freeman, Kenneth; Walsh, Richard; Walls, Bryan K.; Weeks, David J.; Bechtel, Robert T.

1992-01-01

317

The power supply system for the DEPFET pixel detector at BELLE II  

NASA Astrophysics Data System (ADS)

The upgrade of the KEKB accelerator towards 8×1035 cm-2 s-1 poses several challenges for the BELLE II detector. Especially the innermost detector will be faced with a significant radiation of several MRad per year as well as a high hit density. To cope with this a silicon pixel detector will be used for the inner layers of the silicon tracker. The pixel detector (PXD) consists of two layers of DEPFET active pixel sensors. The DEPFET technology has an unique set of advantages like low power dissipation in the active area, flexible device size, radiation hardness and a thinning procedure allowing to adjust the thickness of the device over a wide range. The two layers close to the interaction point together with a low material budget will improve the IP resolution by a factor of 2 compared to the previous installed silicon detector. In addition silicon stand-alone pattern recognition will be possible together with the four layers of double sided strip detectors (DSSD) of the strip detector. The PXD detector system consists of the DEPFET modules with integrated readout chips, the data handling hybrid receiving the data and sending them to compute nodes performing an online pattern recognition. Moreover the power supply system provides the supply voltages for the DEPFET from a position outside of the detector. The power distribution is designed to provide low output impedance over all frequencies and transient response with appropriate overshoots. The PXD pose several challenges to the power distribution system—number of voltages, tight requirements on regulation and noise.

Rummel, Stefan; Depfet Collaboration

2013-01-01

318

Autonomous power system brassboard  

NASA Technical Reports Server (NTRS)

The Autonomous Power System (APS) brassboard is a 20 kHz power distribution system which has been developed at NASA Lewis Research Center, Cleveland, Ohio. The brassboard exists to provide a realistic hardware platform capable of testing artificially intelligent (AI) software. The brassboard's power circuit topology is based upon a Power Distribution Control Unit (PDCU), which is a subset of an advanced development 20 kHz electrical power system (EPS) testbed, originally designed for Space Station Freedom (SSF). The APS program is designed to demonstrate the application of intelligent software as a fault detection, isolation, and recovery methodology for space power systems. This report discusses both the hardware and software elements used to construct the present configuration of the brassboard. The brassboard power components are described. These include the solid-state switches (herein referred to as switchgear), transformers, sources, and loads. Closely linked to this power portion of the brassboard is the first level of embedded control. Hardware used to implement this control and its associated software is discussed. An Ada software program, developed by Lewis Research Center's Space Station Freedom Directorate for their 20 kHz testbed, is used to control the brassboard's switchgear, as well as monitor key brassboard parameters through sensors located within these switches. The Ada code is downloaded from a PC/AT, and is resident within the 8086 microprocessor-based embedded controllers. The PC/AT is also used for smart terminal emulation, capable of controlling the switchgear as well as displaying data from them. Intelligent control is provided through use of a T1 Explorer and the Autonomous Power Expert (APEX) LISP software. Real-time load scheduling is implemented through use of a 'C' program-based scheduling engine. The methods of communication between these computers and the brassboard are explored. In order to evaluate the features of both the brassboard hardware and intelligent controlling software, fault circuits have been developed and integrated as part of the brassboard. A description of these fault circuits and their function is included. The brassboard has become an extremely useful test facility, promoting artificial intelligence (AI) applications for power distribution systems. However, there are elements of the brassboard which could be enhanced, thus improving system performance. Modifications and enhancements to improve the brassboard's operation are discussed.

Merolla, Anthony

1992-01-01

319

Autonomous power system brassboard  

NASA Astrophysics Data System (ADS)

The Autonomous Power System (APS) brassboard is a 20 kHz power distribution system which has been developed at NASA Lewis Research Center, Cleveland, Ohio. The brassboard exists to provide a realistic hardware platform capable of testing artificially intelligent (AI) software. The brassboard's power circuit topology is based upon a Power Distribution Control Unit (PDCU), which is a subset of an advanced development 20 kHz electrical power system (EPS) testbed, originally designed for Space Station Freedom (SSF). The APS program is designed to demonstrate the application of intelligent software as a fault detection, isolation, and recovery methodology for space power systems. This report discusses both the hardware and software elements used to construct the present configuration of the brassboard. The brassboard power components are described. These include the solid-state switches (herein referred to as switchgear), transformers, sources, and loads. Closely linked to this power portion of the brassboard is the first level of embedded control. Hardware used to implement this control and its associated software is discussed. An Ada software program, developed by Lewis Research Center's Space Station Freedom Directorate for their 20 kHz testbed, is used to control the brassboard's switchgear, as well as monitor key brassboard parameters through sensors located within these switches. The Ada code is downloaded from a PC/AT, and is resident within the 8086 microprocessor-based embedded controllers. The PC/AT is also used for smart terminal emulation, capable of controlling the switchgear as well as displaying data from them. Intelligent control is provided through use of a T1 Explorer and the Autonomous Power Expert (APEX) LISP software. Real-time load scheduling is implemented through use of a 'C' program-based scheduling engine. The methods of communication between these computers and the brassboard are explored. In order to evaluate the features of both the brassboard hardware and intelligent controlling software, fault circuits have been developed and integrated as part of the brassboard. A description of these fault circuits and their function is included. The brassboard has become an extremely useful test facility, promoting artificial intelligence (AI) applications for power distribution systems. system performance. &Modifications and enhancements to improve the brassboard's operation are discussed.

Merolla, Anthony

1992-10-01

320

Mission Benefits of Gridded Ion and Hall Thruster Hybrid Propulsion Systems  

NASA Technical Reports Server (NTRS)

The NASA In-Space Propulsion Technology (ISPT) Project Office has been developing the NEXT gridded ion thruster system and is planning to procure a low power Hall system. The new ion propulsion systems will join NSTAR as NASA's primary electric propulsion system options. Studies have been performed to show mission benefits of each of the stand alone systems. A hybrid ion propulsion system (IPS) can have the advantage of reduced cost, decreased flight time and greater science payload delivery over comparable homogeneous systems. This paper explores possible advantages of combining various thruster options for a single mission.

Dankanich, John W.; Polsgrove, Tara

2006-01-01

321

Laser satellite power systems  

SciTech Connect

A laser satellite power system (SPS) converts solar power captured by earth-orbiting satellites into electrical power on the earth's surface, the satellite-to-ground transmission of power being effected by laser beam. The laser SPS may be an alternative to the microwave SPS. Microwaves easily penetrate clouds while laser radiation does not. Although there is this major disadvantage to a laser SPS, that system has four important advantages over the microwave alternative: (1) land requirements are much less, (2) radiation levels are low outside the laser ground stations, (3) laser beam sidelobes are not expected to interfere with electromagnetic systems, and (4) the laser system lends itself to small-scale demonstration. After describing lasers and how they work, the report discusses the five lasers that are candidates for application in a laser SPS: electric discharge lasers, direct and indirect solar pumped lasers, free electron lasers, and closed-cycle chemical lasers. The Lockheed laser SPS is examined in some detail. To determine whether a laser SPS will be worthy of future deployment, its capabilities need to be better understood and its attractiveness relative to other electric power options better assessed. First priority should be given to potential program stoppers, e.g., beam attenuation by clouds. If investigation shows these potential program stoppers to be resolvable, further research should investigate lasers that are particularly promising for SPS application.

Walbridge, E.W.

1980-01-01

322

Power line detection system  

DOEpatents

A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard. 4 figs.

Latorre, V.R.; Watwood, D.B.

1994-09-27

323

Power line detection system  

DOEpatents

A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard.

Latorre, Victor R. (Tracy, CA); Watwood, Donald B. (Tracy, CA)

1994-01-01

324

NASA: Radioisotope Power Systems  

NSDL National Science Digital Library

This is a multimedia overview of RPS (radioisotope power systems), a type of nuclear energy technology that uses heat to produce electricity for powering spacecraft. The heat is produced by the natural radioactive decay of plutonium-238. RPS systems have been in use for more than 50 years, and could continue to support missions to some of the most extreme environments in the solar system. Advantages of RPS include: continuous operation over long-duration space missions, largely independent of changes in sunlight, temperature, charged particle radiation, or surface conditions like thick clouds or dust. This resource is part of NASA's Solar System Exploration website. It includes videos, 3D interactive animations, illustrations, schematics of RPS components, and fact sheets about how the technology has been used in past missions.

325

Sensitivity in Power Systems  

Microsoft Academic Search

Sensitivity is defined as the ratio ¿x\\/¿y relating small changes ¿x of some dependent variable to small changes ¿y of some independent or controllable variable y. In power systems, two dominant types of sensitivity relations are defined, namely 1) sensitivity of one electrical variable, such as the voltage Vi at node i, with respect to another electrical variable, such as

John Peschon; Dean Piercy; William Tinney; Odd Tveit

1968-01-01

326

Autonomously managed electrical power systems  

NASA Technical Reports Server (NTRS)

The electric power systems for future spacecraft such as the Space Station will necessarily be more sophisticated and will exhibit more nearly autonomous operation than earlier spacecraft. These new power systems will be more reliable and flexible than their predecessors offering greater utility to the users. Automation approaches implemented on various power system breadboards are investigated. These breadboards include the Hubble Space Telescope power system test bed, the Common Module Power Management and Distribution system breadboard, the Autonomusly Managed Power System (AMPS) breadboard, and the 20 kilohertz power system breadboard. Particular attention is given to the AMPS breadboard. Future plans for these breadboards including the employment of artificial intelligence techniques are addressed.

Callis, Charles P.

1986-01-01

327

Financial study of commercialization of solar central receiver power systems  

NASA Astrophysics Data System (ADS)

Commercialization requires that central receiver (CR) systems meet the economic criteria used by industry to select systems for capital ventures. Quantitative estimates are given of the investment required by government, utilities, and the manufacturing sector to meet the energy displacement goals for central receiver technology. Initial solar repowering and stand-alone electric utility plants will not have economic comparability with competitive energy sources. A major factor for this is that initial (first of a kind) heliostat costs will be high. As heliostat costs are reduced due to automated manufacturing economies, learning, and high volume production, central receiver technology will become more competitive. Under this task, several scenarios (0.1, 0.5, and 1.0 quad/y) were evaluated to determine the effect on commercial attractiveness and to determine the cost to government to bring about commercialization of solar central receivers.

1981-03-01

328

Power systems testing  

NASA Technical Reports Server (NTRS)

The Space Station Freedom (SSF) will give the U.S. a permanent manned presence in space in 1999. The SSF underwent its final design concept in 1991. Launches of hardware will begin in late 1995, and the SSF will become operational in the man tended configuration in 1997. Additional Space Shuttle flights between 1997 and 1999 will complete the SSF. Along with international partners, a crew of four astronauts will conduct long-term experimentation in the microgravity environment of the orbiting spacecraft. Lewis Research Center, along with its prime contractor, will provide the electrical power system (EPS) for SSF. Two major testing facilities at the Lewis Research Center will support the Lewis EPS. The Power Systems Facility provides test beds for life testing the station batteries and the power management distribution system testbed. This testbed simulates two channels of the EPS. The Space Power Facility at the Lewis Plum Brook Station is the largest vacuum chamber in the world. Within this chamber, a simulated space environment, testing of full-size EPS components will occur.

1991-01-01

329

Heatpipe power system development  

SciTech Connect

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to develop a design approach that could enable the development of near-term, low-cost, space fission-power systems. Sixteen desired attributes were identified for such systems and detailed analyses were performed to verify that they are feasible. Preliminary design work was performed on one concept, the Heatpipe Power system (HPS). As a direct result of this project, funding was obtained from the National Aeronautics and Space Administration to build and test an HPS module. The module tests went well, and they now have funding to build a bimodal module.

Houts, M.G.; Poston, D.I.

1998-12-31

330

High power connection system  

DOEpatents

A high power connection system adapted for automotive environments which provides environmental and EMI shielding includes a female connector, a male connector, and a panel mount. The female connector includes a female connector base and a snap fitted female connector cover. The male connector includes a male connector base and a snap fitted male connector cover. The female connector base has at least one female power terminal cavity for seatably receiving a respective female power terminal. The male connector base has at least one male power terminal cavity for seatably receiving a respective male power terminal. The female connector is covered by a cover seal and a conductive shroud. A pair of lock arms protrude outward from the front end of the male connector base, pass through the panel mount and interface with a lever of a lever rotatably connected to the shroud to thereby mechanically assist mating of the male and female connectors. Safety terminals in the male and female connectors provide a last-to-connect-first-to-break connection with an HVIL circuit.

Schaefer, Christopher E. (Warren, OH); Beer, Robert C. (Noblesville, IN); McCall, Mark D. (Youngstown, OH)

2000-01-01

331

Power systems facility  

NASA Technical Reports Server (NTRS)

In 1984, the President directed NASA to undertake the development of Space Station Freedom, the next step in a broad-based U.S. civil space program to develop space-flight capabilities and to exploit space for scientific, technological, and commercial purposes. Under that direction, NASA awarded contracts in 1985 for concept definition and preliminary design studies. Those studies have been completed and the Space Station Freedom Program is now in the final design and development phase, leading to a permanently manned space station that will be operational in the mid-1990's. Here at the Lewis Research Center, with Rocketdyne, we are developing and building the S.S. Freedom electric power system (EPS) hardware and software. A major portion of the EPS will be tested at Lewis. The Power Systems Facility was specifically designed for testing the EPS and uses the latest in testing equipment.

1989-01-01

332

Power control system and method  

DOEpatents

A power system includes an energy harvesting device, a battery coupled to the energy harvesting device, and a circuit coupled to the energy harvesting device and the battery. The circuit is adapted to deliver power to a load by providing power generated by the energy harvesting device to the load without delivering excess power to the battery and to supplement the power generated by the energy harvesting device with power from the battery if the power generated by the energy harvesting device is insufficient to fully power the load. A method of operating the power system is also provided.

Steigerwald, Robert Louis (Burnt Hills, NY) [Burnt Hills, NY; Anderson, Todd Alan (Niskayuna, NY) [Niskayuna, NY

2008-02-19

333

Power control system and method  

DOEpatents

A power system includes an energy harvesting device, a battery coupled to the energy harvesting device, and a circuit coupled to the energy harvesting device and the battery. The circuit is adapted to deliver power to a load by providing power generated by the energy harvesting device to the load without delivering excess power to the battery and to supplement the power generated by the energy harvesting device with power from the battery if the power generated by the energy harvesting device is insufficient to fully power the load. A method of operating the power system is also provided.

Steigerwald, Robert Louis; Anderson, Todd Alan

2006-11-07

334

Lunar power systems  

NASA Technical Reports Server (NTRS)

The findings of a study on the feasibility of several methods of providing electrical power for a permanently manned lunar base are provided. Two fundamentally different methods for lunar electrical power generation are considered. One is the use of a small nuclear reactor and the other is the conversion of solar energy to electricity. The baseline goal was to initially provide 300 kW of power with growth capability to one megawatt and eventually to 10 megawatts. A detailed, day by day scenario for the establishment, build-up, and operational activity of the lunar base is presented. Also presented is a conceptual approach to a supporting transportation system which identifies the number, type, and deployment of transportation vehicles required to support the base. An approach to the use of solar cells in the lunar environment was developed. There are a number of heat engines which are applicable to solar/electric conversions, and these are examined. Several approaches to energy storage which were used by the electric power utilities were examined and those which could be used at a lunar base were identified.

1986-01-01

335

Active power conditioner system  

SciTech Connect

A system is described for power conditioning a line of supply of AC power from an AC source to an AC load, comprising: a first array of static power switches mounted across one AC source and AC load; a second array of static power switches coupled in series with the AC supply line; a DC source connected between the first and second arrays; first controlling means operative upon the first array in one of two modes to effect conversion between one of the AC source and AC load on one side and the DC source on the other side; second controlling means operative upon the second array in one of two modes to effect conversion between the DC source on one side and the AC supply line on the other side; the first array operating as a rectifier when the second array operates an an inverter, and the first array operating as an inverter when the second array operates as a rectifier; whereby the first and second controlling means provide one of a buck and boost voltage on the AC supply line while maintaining the DC source constant.

Stacey, E.J.; Brennen, M.B.

1987-03-17

336

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

337

Storage systems for tidal power  

Microsoft Academic Search

The effective use of tidal power by a typical electrical power system requires energy storage to retime the input to meet load demand. The cost of tidal power generation is relatively high and cannot be economically absorbed by the power system as secondary energy. Its constitution is more valuable when delivered at intermediate load factors. Traditional modes of \\

J. Warnock

1974-01-01

338

Use of super capacitors to reduce the fast fluctuations of power of a hybrid system composed of photovoltaic and micro turbine  

Microsoft Academic Search

In this paper, we propose to study the possibility of using a photovoltaic system combined with a high speed micro-turbine. This hybrid system can work as stand-alone system or grid connected system as it will be a part of a micro-grid. Initially, we propose simple dynamic models of photovoltaic and micro turbine systems. Then, we carry out a comparison between

Ph. Degobert; S. Kreuawan; X. Guillaud

2006-01-01

339

Power Systems Development Facility  

SciTech Connect

This report discusses Test Campaign TC12 of the Kellogg Brown & Root, Inc. (KBR) Transport Gasifier train with a Siemens Westinghouse Power Corporation (SW) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Gasifier is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using a particulate control device (PCD). While operating as a gasifier, either air or oxygen can be used as the oxidant. Test run TC12 began on May 16, 2003, with the startup of the main air compressor and the lighting of the gasifier start-up burner. The Transport Gasifier operated until May 24, 2003, when a scheduled outage occurred to allow maintenance crews to install the fuel cell test unit and modify the gas clean-up system. On June 18, 2003, the test run resumed when operations relit the start-up burner, and testing continued until the scheduled end of the run on July 14, 2003. TC12 had a total of 733 hours using Powder River Basin (PRB) subbituminous coal. Over the course of the entire test run, gasifier temperatures varied between 1,675 and 1,850 F at pressures from 130 to 210 psig.

None

2003-07-01

340

Wind Energy System Time-domain (WEST) analyzers using hybrid simulation techniques  

NASA Technical Reports Server (NTRS)

Two stand-alone analyzers constructed for real time simulation of the complex dynamic characteristics of horizontal-axis wind energy systems are described. Mathematical models for an aeroelastic rotor, including nonlinear aerodynamic and elastic loads, are implemented with high speed digital and analog circuitry. Models for elastic supports, a power train, a control system, and a rotor gimbal system are also included. Limited correlation efforts show good comparisons between results produced by the analyzers and results produced by a large digital simulation. The digital simulation results correlate well with test data.

Hoffman, J. A.

1979-01-01

341

Power flow for spacecraft power systems  

NASA Technical Reports Server (NTRS)

A method for constructing the generalized system-level admittance matrix for use with a Newton-Raphson power flow is presented. The network modeling technique presented does not use the standard pi-equivalent models, which assume a lossless return path, for the transmission line and transformer. If the return path cannot be assumed lossless, then the standard algorithms for constructing the system admittance matrix cannot be used. The method presented here uses concepts from linear graph theory to combine network modules to form the system-level admittance matrix. The modeling technique is presented, and the resulting matrix is used with a standard Newton-Raphson power flow to calculate all system voltages and current (power) flows.

Halpin, S. M.; Grigsby, L. L.; Sheble, G. B.; Nelms, R. M.

1989-01-01

342

Automated mapping system for the Igliniit (Trails) Project   

E-print Network

The goal of this research is to investigate the potential for creating a stand-alone mapping system for the Igliniit Project. An original application, called the “Igliniit Viewer” has been developed as proof of concept. ...

Wilson, Karl-Erik

2010-11-24

343

Introduction to Spectroscopy PowerPoint Presentation  

NSDL National Science Digital Library

This is a downloadable PowerPoint presentation about spectroscopy. Learners read and/or hear about the science of spectroscopy, what a spectrum is, and how spectroscopy is important to astronomy. This PowerPoint accompanies the Stanford Solar Center's Build Your Own Spectroscope activity, but it can be used as a stand-alone presentation for learners.

2013-02-15

344

Automated Power Systems Management (APSM)  

NASA Technical Reports Server (NTRS)

A breadboard power system incorporating autonomous functions of monitoring, fault detection and recovery, command and control was developed, tested and evaluated to demonstrate technology feasibility. Autonomous functions including switching of redundant power processing elements, individual load fault removal, and battery charge/discharge control were implemented by means of a distributed microcomputer system within the power subsystem. Three local microcomputers provide the monitoring, control and command function interfaces between the central power subsystem microcomputer and the power sources, power processing and power distribution elements. The central microcomputer is the interface between the local microcomputers and the spacecraft central computer or ground test equipment.

Bridgeforth, A. O.

1981-01-01

345

POWER SYSTEMS DEVELOPMENT FACILITY  

SciTech Connect

This report discusses test campaign GCT4 of the Kellogg Brown & Root, Inc. (KBR) transport reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The transport reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using one of two possible particulate control devices (PCDs). The transport reactor was operated as a pressurized gasifier during GCT4. GCT4 was planned as a 250-hour test run to continue characterization of the transport reactor using a blend of several Powder River Basin (PRB) coals and Bucyrus limestone from Ohio. The primary test objectives were: Operational Stability--Characterize reactor loop and PCD operations with short-term tests by varying coal-feed rate, air/coal ratio, riser velocity, solids-circulation rate, system pressure, and air distribution. Secondary objectives included the following: Reactor Operations--Study the devolatilization and tar cracking effects from transient conditions during transition from start-up burner to coal. Evaluate the effect of process operations on heat release, heat transfer, and accelerated fuel particle heat-up rates. Study the effect of changes in reactor conditions on transient temperature profiles, pressure balance, and product gas composition. Effects of Reactor Conditions on Synthesis Gas Composition--Evaluate the effect of air distribution, steam/coal ratio, solids-circulation rate, and reactor temperature on CO/CO{sub 2} ratio, synthesis gas Lower Heating Value (LHV), carbon conversion, and cold and hot gas efficiencies. Research Triangle Institute (RTI) Direct Sulfur Recovery Process (DSRP) Testing--Provide syngas in support of the DSRP commissioning. Loop Seal Operations--Optimize loop seal operations and investigate increases to previously achieved maximum solids-circulation rate.

Unknown

2002-11-01

346

Continuous hydrino thermal power system  

Microsoft Academic Search

The specifics of a continuous hydrino reaction system design are presented. Heat from the hydrino reactions within individual cells provide both reactor power and the heat for regeneration of the reactants. These processes occur continuously and the power from each cell is constant. The conversion of thermal power to electrical power requires the use of a heat engine exploiting a

Randell L. Mills; Guibing Zhao; William Good

2011-01-01

347

Development of a multiplane multispeed balancing system for turbine systems  

NASA Technical Reports Server (NTRS)

A prototype high speed balancing system was developed for assembled gas turbine engine modules. The system permits fully assembled gas turbine modules to be operated and balanced at selected speeds up to full turbine speed. The balancing system is a complete stand-alone system providing all necesary lubrication and support hardware for full speed operation. A variable speed motor provides the drive power. A drive belt and gearbox provide rotational speeds up to 21,000 rpm inside a vacuum chamber. The heart of the system is a dedicated minicomputer with attendant data acquisition, storage and I/O devices. The computer is programmed to be completely interactive with the operator. The system was installed at CCAD and evaluated by testing 20 T55 power turbines and 20 T53 power turbines. Engine test results verified the performance of the high speed balanced turbines.

Martin, M. R.

1984-01-01

348

Solar thermal power system  

DOEpatents

A solar thermal power generator includes an inclined elongated boiler tube positioned in the focus of a solar concentrator for generating steam from water. The boiler tube is connected at one end to receive water from a pressure vessel as well as connected at an opposite end to return steam back to the vessel in a fluidic circuit arrangement that stores energy in the form of heated water in the pressure vessel. An expander, condenser, and reservoir are also connected in series to respectively produce work using the steam passed either directly (above a water line in the vessel) or indirectly (below a water line in the vessel) through the pressure vessel, condense the expanded steam, and collect the condensed water. The reservoir also supplies the collected water back to the pressure vessel at the end of a diurnal cycle when the vessel is sufficiently depressurized, so that the system is reset to repeat the cycle the following day. The circuital arrangement of the boiler tube and the pressure vessel operates to dampen flow instabilities in the boiler tube, damp out the effects of solar transients, and provide thermal energy storage which enables time shifting of power generation to better align with the higher demand for energy during peak energy usage periods.

Bennett, Charles L.

2010-06-15

349

Satellite Power System (SPS)  

NASA Technical Reports Server (NTRS)

Potential organizational options for a solar power satellite system (SPS) were investigated. Selection and evaluation criteria were determined to include timeliness, reliability, and adequacy to contribute meaningfully to the U.S. supply; political feasibility (both national and international); and cost effectiveness (including environmental and other external costs). Based on these criteria, four organizational alternatives appeared to offer reasonable promise as potential options for SPS. A large number of key issues emerged as being factors which would influence the final selection process. Among these issues were a variety having to do with international law, international institutions, environmental controls, economics, operational flexibility, congressional policies, commercial-vs-governmental ownership, national dedication, and national and operational stategic issues.

Edler, H. G.

1978-01-01

350

Batteries and Power Systems  

NSDL National Science Digital Library

All About Circuits is a website that â??provides a series of online textbooks covering electricity and electronics.â? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Batteries and Power Systems, is the eleventh chapter in Volume I â??Direct Current. A few of the topics covered in this chapter include: Battery construction, Battery ratings, Special-purpose batteries, and Electron activity in chemical reactions. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

Kuphaldt, Tony R.

351

Operational performance of the photovoltaic-powered grain mill and water pump at Tangaye, Upper Volta  

NASA Technical Reports Server (NTRS)

The first two years of operation of a stand alone photovoltaic (PV) power system for the village of Tangaye, Upper Volta in West Africa are described. The purpose of the experiment was to demonstrate that PV systems could provide reliable electrical power for multiple use applications in remote areas where local technical expertise is limited. The 1.8 kW (peak) power system supplies 120-V (d.c.) electrical power to operate a grain mill, a water pump, and mill building lights for the village. The system was initially sized to pump a part of the village water requirements from an existing improved well, and to meet a portion of the village grain grinding requirements. The data, observations, experiences, and conclusions developed during the first two years of operation are discussed. Reports of tests of the mills used in the project are included.

Martz, J. E.; Ratajczak, A. F.; Delombard, R.

1982-01-01

352

Operational performance of the photovoltaic-powered grain mill and water pump at Tangaye, Upper Volta  

SciTech Connect

The first two years of operation of a stand alone photovoltaic (PV) power system for the village of Tangaye, Upper Volta in West Africa are described. The purpose of the experiment was to demonstrate that PV systems could provide reliable electrical power for multiple use applications in remote areas where local technical expertise is limited. The 1.8 kW (peak) power system supplies 120-V (d.c.) electrical power to operate a grain mill, a water pump, and mill building lights for the village. The system was initially sized to pump a part of the village water requirements from an existing improved well, and to meet a portion of the village grain grinding requirements. The data, observations, experiences, and conclusions developed during the first two years of operation are discussed. Reports of tests of the mills used in the project are included.

Martz, J.E.; Ratajczak, A.F.; Delombard, R.

1982-02-01

353

Overview of MC Power`s MCFC power generation system  

Microsoft Academic Search

The IMHEX{reg_sign} fuel cell power generation system is a skid mounted power plant which efficiently generates electricity and useful thermal energy. The primary benefits are its high electric generation efficiency (50% or greater), modular capacities (500 kW to 3 MW per unit) and minimal environmental impacts (less than 1 ppM NOâ). A cost effective, modular capacity fuel cell power plant

T. G. Benjamin; R. R. Woods

1993-01-01

354

Simulation of the performance of a 100-kW-peak photovoltaic system  

SciTech Connect

MIT Lincoln Laboratory designed and is currently constructing a 100-kW-peak photovoltaic (PV) power system for the Natural Bridges National Monument (NBNM). NBNM is located in a remote part of southeastern Utah and the PV system will operate in a stand-alone mode (i.e., no tie-in with a utility grid). Backup power will be supplied by an existing diesel-powered generator. The PV system and its individual components are being analyzed through the use of a computer simulation. Useful relationships have been found for system operating characteristics, array output, generator power usage, generator control strategy, storage losses and battery charge/discharge cycles. The system operating voltage can be set to extract maximum power from the array during the winter when that power is needed most. The generator operating strategy can be designed to minimize adverse effects on the batteries. Losses due to storage are offset by surplus array energy and by generator power.

Grossman, B.L.; Brench, B.L.; Bucciarelli, L.L.; Solman, F.J.

1980-01-01

355

Body powered thermoelectric systems  

E-print Network

Great interest exists for and progress has be made in the effective utilization of the human body as a possible power supply in hopes of powering such applications as sensors and continuously monitoring medical devices ...

Settaluri, Krishna Tej

2012-01-01

356

Performance evaluation of adding ethanol production into an existing combined heat and power plant.  

PubMed

In this paper, the configuration and performance of a polygeneration system are studied by modelling the integration of a lignocellulosic wood-to-ethanol process with an existing combined heat and power (CHP) plant. Data from actual plants are applied to validate the simulation models. The integrated polygeneration system reaches a total efficiency of 50%, meeting the heating load in the district heating system. Excess heat from the ethanol production plant supplies 7.9 MW to the district heating system, accounting for 17.5% of the heat supply at full heating load. The simulation results show that the production of ethanol from woody biomass is more efficient when integrated with a CHP plant compared to a stand-alone production plant. The total biomass consumption is reduced by 13.9% while producing the same amounts of heat, electricity and ethanol fuel as in the stand-alone configurations. The results showed that another feature of the integrated polygeneration system is the longer annual operating period compared to existing cogeneration. Thus, the renewable electricity production is increased by 2.7% per year. PMID:19758800

Starfelt, F; Thorin, E; Dotzauer, E; Yan, J

2010-01-01

357

Enhancing small signal power system stability by coordinating unified power flow controller with power system stabilizer  

Microsoft Academic Search

Advancement of power electronic technologies makes ac systems to be more adaptive and flexible as new forms of power controller emerges in recent years. Though not yet well developed, underpinned research suggests that unified power flow controller (UPFC) is a promising power system controller. This paper proposes a method to coordinate UPFC with power system stabilizer (PSS) so as to

Wanliang Fang; H. W. Ngan

2003-01-01

358

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.

359

Switching power pulse system  

DOEpatents

A switching system for delivering pulses of power from a source to a load using a storage capacitor charged through a rectifier, and maintained charged to a reference voltage level by a transistor switch and voltage comparator. A thyristor is triggered to discharge the storage capacitor through a saturable reactor and fractional turn saturable transformer having a secondary to primary turn ratio N of n:l/n = n[sup 2]. The saturable reactor functions as a soaker'' while the thyristor reaches saturation, and then switches to a low impedance state. The saturable transformer functions as a switching transformer with high impedance while a load coupling capacitor charges, and then switches to a low impedance state to dump the charge of the storage capacitor into the load through the coupling capacitor. The transformer is comprised of a multilayer core having two secondary windings tightly wound and connected in parallel to add their output voltage and reduce output inductance, and a number of single turn windings connected in parallel at nodes for the primary winding, each single turn winding linking a different one of the layers of the multilayer core. The load may be comprised of a resistive beampipe for a linear particle accelerator and capacitance of a pulse forming network. To hold off discharge of the capacitance until it is fully charged, a saturable core is provided around the resistive beampipe to isolate the beampipe from the capacitance until it is fully charged. 5 figs.

Aaland, K.

1983-08-09

360

Automated application-specific optimisation of interconnects in multi-core systems   

E-print Network

In embedded computer systems there are often tasks, implemented as stand-alone devices, that are both application-specific and compute intensive. A recurring problem in this area is to design these application-specific ...

Almer, Oscar Erik Gabriel

2012-11-29

361

Power recovery and feedback system  

Microsoft Academic Search

A system for recovering otherwise lost power from a compressor and prime mover utilizing a Rankine cycle is disclosed. While heat recovery from prime movers has been done, much energy is wasted by compressors which convert all the driving power to heat which has not been recovered. Thus, this invention provides for power recovery from both the prime mover and

Johnson

1980-01-01

362

POWER SYSTEMS DEVELOPMENT FACILITY  

SciTech Connect

This report discusses test campaign GCT3 of the Halliburton KBR transport reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The transport reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using one of two possible particulate control devices (PCDs). The transport reactor was operated as a pressurized gasifier during GCT3. GCT3 was planned as a 250-hour test run to commission the loop seal and continue the characterization of the limits of operational parameter variations using a blend of several Powder River Basin coals and Bucyrus limestone from Ohio. The primary test objectives were: (1) Loop Seal Commissioning--Evaluate the operational stability of the loop seal with sand and limestone as a bed material at different solids circulation rates and establish a maximum solids circulation rate through the loop seal with the inert bed. (2) Loop Seal Operations--Evaluate the loop seal operational stability during coal feed operations and establish maximum solids circulation rate. Secondary objectives included the continuation of reactor characterization, including: (1) Operational Stability--Characterize the reactor loop and PCD operations with short-term tests by varying coal feed, air/coal ratio, riser velocity, solids circulation rate, system pressure, and air distribution. (2) Reactor Operations--Study the devolatilization and tar cracking effects from transient conditions during transition from start-up burner to coal. Evaluate the effect of process operations on heat release, heat transfer, and accelerated fuel particle heat-up rates. Study the effect of changes in reactor conditions on transient temperature profiles, pressure balance, and product gas composition. (3) Effects of Reactor Conditions on Syngas Composition--Evaluate the effect of air distribution, steam/coal ratio, solids circulation rate, and reactor temperature on CO/CO{sub 2} ratio, H{sub 2}/converted carbon ratio, gasification rates, carbon conversion, and cold and hot gas efficiencies. Test run GCT3 was started on December 1, 2000, with the startup of the thermal oxidizer fan, and was completed on February 1, 2001. This test was conducted in two parts; the loop seal was commissioned during the first part of this test run from December 1 through 15, which consisted of hot inert solids circulation testing. These initial tests provided preliminary data necessary to understand different parameters associated with the operation and performance of the loop seal. The loop seal was tested with coal feed during the second part of the test run and additional data was gathered to analyze reactor operations and to identify necessary modifications to improve equipment and process performance. In the second part of GCT3, the gasification portion of the test, from January 20 to February 1, 2001, the mixing zone and riser temperatures were varied between 1,675 and 1,825 F at pressures ranging from 200 to 240 psig. There were 306 hours of solid circulation and 184 hours of coal feed attained in GCT3.

Unknown

2002-05-01

363

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

364

Optimal design and control strategies for novel combined heat and power (CHP) fuel cell systems. Part II of II, case study results.  

SciTech Connect

Innovative energy system optimization models are deployed to evaluate novel fuel cell system (FCS) operating strategies, not typically pursued by commercial industry. Most FCS today are installed according to a 'business-as-usual' approach: (1) stand-alone (unconnected to district heating networks and low-voltage electricity distribution lines), (2) not load following (not producing output equivalent to the instantaneous electrical or thermal demand of surrounding buildings), (3) employing a fairly fixed heat-to-power ratio (producing heat and electricity in a relatively constant ratio to each other), and (4) producing only electricity and no recoverable heat. By contrast, models discussed here consider novel approaches as well. Novel approaches include (1) networking (connecting FCSs to electrical and/or thermal networks), (2) load following (having FCSs produce only the instantaneous electricity or heat demanded by surrounding buildings), (3) employing a variable heat-to-power ratio (such that FCS can vary the ratio of heat and electricity they produce), (4) co-generation (combining the production of electricity and recoverable heat), (5) permutations of these together, and (6) permutations of these combined with more 'business-as-usual' approaches. The detailed assumptions and methods behind these models are described in Part I of this article pair.

Colella, Whitney G.

2010-06-01

365

Optimizal design and control strategies for novel Combined Heat and Power (CHP) fuel cell systems. Part II of II, case study results.  

SciTech Connect

Innovative energy system optimization models are deployed to evaluate novel fuel cell system (FCS) operating strategies, not typically pursued by commercial industry. Most FCS today are installed according to a 'business-as-usual' approach: (1) stand-alone (unconnected to district heating networks and low-voltage electricity distribution lines), (2) not load following (not producing output equivalent to the instantaneous electrical or thermal demand of surrounding buildings), (3) employing a fairly fixed heat-to-power ratio (producing heat and electricity in a relatively constant ratio to each other), and (4) producing only electricity and no recoverable heat. By contrast, models discussed here consider novel approaches as well. Novel approaches include (1) networking (connecting FCSs to electrical and/or thermal networks), (2) load following (having FCSs produce only the instantaneous electricity or heat demanded by surrounding buildings), (3) employing a variable heat-to-power ratio (such that FCS can vary the ratio of heat and electricity they produce), (4) co-generation (combining the production of electricity and recoverable heat), (5) permutations of these together, and (6) permutations of these combined with more 'business-as-usual' approaches.

Colella, Whitney G.

2010-04-01

366

Switching power pulse system  

DOEpatents

A switching system for delivering pulses of power from a source (10) to a load (20) using a storage capacitor (C3) charged through a rectifier (D1, D2), and maintained charged to a reference voltage level by a transistor switch (Q1) and voltage comparator (12). A thyristor (22) is triggered to discharge the storage capacitor through a saturable reactor (18) and fractional turn saturable transformer (16) having a secondary to primary turn ratio N of n:l/n=n.sup.2. The saturable reactor (18) functions as a "soaker" while the thyristor reaches saturation, and then switches to a low impedance state. The saturable transformer functions as a switching transformer with high impedance while a load coupling capacitor (C4) charges, and then switches to a low impedance state to dump the charge of the storage capacitor (C3) into the load through the coupling capacitor (C4). The transformer is comprised of a multilayer core (26) having two secondary windings (28, 30) tightly wound and connected in parallel to add their output voltage and reduce output inductance, and a number of single turn windings connected in parallel at nodes (32, 34) for the primary winding, each single turn winding linking a different one of the layers of the multilayer core. The load may be comprised of a resistive beampipe (40) for a linear particle accelerator and capacitance of a pulse forming network (42). To hold off discharge of the capacitance until it is fully charged, a saturable core (44) is provided around the resistive beampipe (40) to isolate the beampipe from the capacitance (42) until it is fully charged.

Aaland, Kristian (Livermore, CA)

1983-01-01

367

Advanced Power System Analysis Capabilities  

NASA Technical Reports Server (NTRS)

As a continuing effort to assist in the design and characterization of space power systems, the NASA Lewis Research Center's Power and Propulsion Office developed a powerful computerized analysis tool called System Power Analysis for Capability Evaluation (SPACE). This year, SPACE was used extensively in analyzing detailed operational timelines for the International Space Station (ISS) program. SPACE was developed to analyze the performance of space-based photovoltaic power systems such as that being developed for the ISS. It is a highly integrated tool that combines numerous factors in a single analysis, providing a comprehensive assessment of the power system's capability. Factors particularly critical to the ISS include the orientation of the solar arrays toward the Sun and the shadowing of the arrays by other portions of the station.

1997-01-01

368

Photovoltaic power system reliability considerations  

NASA Technical Reports Server (NTRS)

An example of how modern engineering and safety techniques can be used to assure the reliable and safe operation of photovoltaic power systems is presented. This particular application is for a solar cell power system demonstration project designed to provide electric power requirements for remote villages. The techniques utilized involve a definition of the power system natural and operating environment, use of design criteria and analysis techniques, an awareness of potential problems via the inherent reliability and FMEA methods, and use of fail-safe and planned spare parts engineering philosophy.

Lalli, V. R.

1980-01-01

369

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

370

Mobile nuclear power systems  

NASA Astrophysics Data System (ADS)

Nuclear reactors where the energy comes from nuclear fission and isotopic generators utilizing the energy of the decay of suitable isotopes are discussed. The reactors are used as power sources on board nuclear submarines and other warships, as well as in space and in remote places. Their thermal power ranges from 30 KWth in a satellite to 175 MWth on board an aircraft carrier. Isotopic generators are suitable only for small power demands and are used on board satellites and spaceprobes, automatic weather stations, lighthouses, and marine installations for navigation and observation.

Andersson, Bengt

1988-11-01

371

Nanosatellite Power System Considerations  

NASA Technical Reports Server (NTRS)

The capability to build complex electronic functions into compact packages is opening the path to miniature satellites on the order of 1 kg mass, 10 cm across, packed with the computing processors, motion controllers, measurement sensors, and communications hardware necessary for operation. Power generation will be from short strings of silicon or gallium arsenide-based solar photovoltaic cells with the array power maximized by a peak power tracker (PPT). Energy storage will utilize a low voltage battery with nickel cadmium or lithium ion cells as the most likely selections for rechargeables and lithium (MnO2-Li) primary batteries for one shot short missions.

Robyn, M.; Thaller, L.; Scott, D.

1995-01-01

372

Power Systems of the Future  

E-print Network

Electric power is a vital ingredient of modern society. This paper in conjunction with previous papers was written to provide an insight into the physics and engineering that go into electric power systems and their modernization. Topics covered here are Direct Current; Superconducting Generators; Energy Storage; Voltage Sags; Grid Stability, Power System Planning and Operations; Biological Effects of Electromagnetic Fields; Dispersed Generation; Information Superhighway Synergy; Distribution Automation; Conclusion.

Mario Rabinowitz

2003-04-30

373

Electrical power systems for Mars  

NASA Technical Reports Server (NTRS)

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.

1986-01-01

374

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

375

Research and simulation on photovoltaic power system maximum power control  

Microsoft Academic Search

Photovoltaic power generation system implements an effective utilization of solar energy, but generally has very low conversion efficiency. Maximum power point tracker (MPPT) control is essential to ensure the output of photovoltaic power generation system at the maximum power output as possible. Photovoltaic cells model of photovoltaic power generation system and basic control algorithm is discussed in this paper. MPPT

Ling Lu; Ping Liu

2011-01-01

376

Overview of power loss measurement techniques in power electronics systems  

Microsoft Academic Search

Measuring power loss accurately is of great importance for power electronics systems design and for assessing system performance and reliability. This paper reviews various power loss measurement techniques in power electronics systems. A brief overview of electrical methods for loss measurements is given. Calorimetric methods, the most accurate of all instruments for measuring power loss, are described along with their

Chucheng Xiao; Gang Chen; W. G. Odendaal

2002-01-01

377

Wave power systems  

Microsoft Academic Search

Ocean wave power was investigated as a usable, renewable, alternative energy source. The results suggest that both Salter cams and Cockerell rafts can be designed to convert wave motion to relative mechanical motion and mechanical forces. Mooring problems and costs suggest that Salter cams will be much more expensive than Cockerell rafts. A major problem is converting the available mechanical

N. Doelling

1979-01-01

378

Reactive power compensating system  

DOEpatents

The reactive power of an induction machine is compensated by providing fixed capacitors on each phase line for the minimum compensation required, sensing the current on one line at the time its voltage crosses zero to determine the actual compensation required for each phase, and selecting switched capacitors on each line to provide the balance of the compensation required.

Williams, Timothy J. (Redondo Beach, CA); El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Seattle, WA)

1987-01-01

379

Reactive Power Compensating System.  

DOEpatents

The circuit was designed for the specific application of wind-driven induction generators. It has great potential for application in any situation where a varying reactive power load is present, such as with induction motors or generators, or for transmission network compensation.

Williams, Timothy J.; El-Sharkawi, Mohamed A.; Venkata, Subrahmanyam S.

1985-01-04

380

Information System Security Critical Elements Please note that prior to including this language in the performance plans of employees covered by  

E-print Network

Information System Security Critical Elements Please note that prior to including this language fulfilled. Stand-Alone Critical Elements Senior Agency Information Security Officer/Chief Information Security Officer/ Information Technology Security Officer Critical Element and Objective · Senior Agency

381

Space power systems technology  

NASA Technical Reports Server (NTRS)

Reported here is a series of studies which examine several potential catalysts and electrodes for some fuel cell systems, some materials for space applications, and mathematical modeling and performance predictions for some solid oxide fuel cells and electrolyzers. The fuel cell systems have a potential for terrestrial applications in addition to solar energy conversion in space applications. Catalysts and electrodes for phosphoric acid fuel cell systems and for polymer electrolyte membrane (PEM) fuel cell and electrolyzer systems were examined.

Coulman, George A.

1994-01-01

382

Power generation systems and methods  

NASA Technical Reports Server (NTRS)

A power generation system includes a plurality of submerged mechanical devices. Each device includes a pump that can be powered, in operation, by mechanical energy to output a pressurized output liquid flow in a conduit. Main output conduits are connected with the device conduits to combine pressurized output flows output from the submerged mechanical devices into a lower number of pressurized flows. These flows are delivered to a location remote of the submerged mechanical devices for power generation.

Jones, Jack A. (Inventor); Chao, Yi (Inventor)

2011-01-01

383

Power systems for future missions  

NASA Technical Reports Server (NTRS)

A comprehensive scenario of future missions was developed and applicability of different power technologies to these missions was assessed. Detailed technology development roadmaps for selected power technologies were generated. A simple methodology to evaluate economic benefits of current and future power system technologies by comparing Life Cycle Costs of potential missions was developed. The methodology was demonstrated by comparing Life Cycle Costs for different implementation strategies of DIPS/CBC technology to a selected set of missions.

Gill, S. P.; Frye, P. E.; Littman, Franklin D.; Meisl, C. J.

1994-01-01

384

Hybrid electric power generating system  

Microsoft Academic Search

A hybrid power system is described which consists of: (a) a first energy converter operating on a closed Rankine cycle and including a vapor generator for vaporizing an organic working fluid in response to heat furnished from a heat source associated with the vapor generator. A turbogenerator is responsive to vaporized working fluid for generating electrical power and a condenser

Bronicki

1986-01-01

385

Hybrid electric power generating system  

Microsoft Academic Search

A hybrid power system is described which comprises a pair of energy converters operating on a closed Rankine cycle, each energy converter having a vapor generator for vaporizing a high molecular weight working fluid in response to heat furnished from a burner associated with the generator, a turbo-generator responsive to vaporized working fluid for generating electrical power, a condenser responsive

Bronicki

1978-01-01

386

Power enhanced frequency conversion system  

NASA Technical Reports Server (NTRS)

A frequency conversion system includes at least one source providing a first near-IR wavelength output including a gain medium for providing high power amplification, such as double clad fiber amplifier, a double clad fiber laser or a semiconductor tapered amplifier to enhance the power output level of the near-IR wavelength output. The NFM device may be a difference frequency mixing (DFM) device or an optical parametric oscillation (OPO) device. Pump powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Ra-man/Brillouin amplifier or oscillator between the high power source and the NFM device.

Sanders, Steven (Inventor); Lang, Robert J. (Inventor); Waarts, Robert G. (Inventor)

2001-01-01

387

Power turbine ventilation system  

NASA Technical Reports Server (NTRS)

Air control mechanism within a power turbine section of a gas turbine engine. The power turbine section includes a rotor and at least one variable pitch propulsor blade. The propulsor blade is coupled to and extends radially outwardly of the rotor. A first annular fairing is rotatable with the propulsor blade and interposed between the propulsor blade and the rotor. A second fairing is located longitudinally adjacent to the first fairing. The first fairing and the second fairing are differentially rotatable. The air control mechanism includes a platform fixedly coupled to a radially inner end of the propulsor blade. The platform is generally positioned in a first opening and a first fairing. The platform and the first fairing define an outer space. In a first position corresponding with a first propulsor blade pitch, the platform is substantially conformal with the first fairing. In a second position corresponding with the second propulsor blade pitch, an edge portion of the platform is displaced radially outwardly from the first fairing. When the blades are in the second position and rotating about the engine axis, the displacement of the edge portion with respect to the first fairing allows air to flow from the outer space to the annular cavity.

Wakeman, Thomas G. (Inventor); Brown, Richard W. (Inventor)

1991-01-01

388

Power System Stability Enhancement using Interline Power Flow Controller  

Microsoft Academic Search

FACTS technology improves the power system stability by providing the necessary compensation to transmission lines. Interline Power Flow Controller (IPFC) is one such unique concept for exchange of power flow in case of interconnected systems. In this paper, an IPFC is proposed to improve the voltage stability of a given power system network consisting of three transmission lines. The gate

R. SARAVANA KUMAR; M. PRABHAKAR

389

Overview of Power Loss Measurement Techniques in Power Electronics Systems  

Microsoft Academic Search

Measuring power loss accurately is of great importance for power electronics systems design and for assessing system performance and reliability. This paper reviews various power loss measurement techniques in power electronics systems. A brief overview of electrical methods for loss measurements is given. Calorimetric methods, which are considered the most accurate of this purpose, are described along with their implementations.

Chucheng Xiao; Gang Chen; Willem G. H. Odendaal

2007-01-01

390

Locating unified power flow controller for enhancing power system loadability  

Microsoft Academic Search

In a power system transmission network, there are some corridors which are lightly loaded whereas some of the corridors are critically loaded and thus power system is operating near to critical state. Flexible AC transmission systems (FACTS) plays a vital role in improving the power system performance, both the static and dynamic, and enhanced the system loading capability by rerouting

S. N. Singh; I. Erlich

2005-01-01

391

Analysis methods for wind turbine control and electrical system dynamics  

NASA Astrophysics Data System (ADS)

The integration of new energy technologies into electric power systems requires methods which recognize the full range of dynamic events in both the new generating unit and the power system. Since new energy technologies are initially perceived as small contributors to large systems, little attention is generally paid to system integration, i.e. dynamic events in the power system are ignored. As a result, most new energy sources are only capable of base-load operation, i.e. they have no load following or cycling capability. Wind turbines are no exception. Greater awareness of this implicit (and often unnecessary) limitation is needed. Analysis methods are recommended which include very low penetration (infinite bus) as well as very high penetration (stand-alone) scenarios.

Hinrichsen, E. N.

1995-05-01

392

Analysis methods for wind turbine control and electrical system dynamics  

NASA Technical Reports Server (NTRS)

The integration of new energy technologies into electric power systems requires methods which recognize the full range of dynamic events in both the new generating unit and the power system. Since new energy technologies are initially perceived as small contributors to large systems, little attention is generally paid to system integration, i.e. dynamic events in the power system are ignored. As a result, most new energy sources are only capable of base-load operation, i.e. they have no load following or cycling capability. Wind turbines are no exception. Greater awareness of this implicit (and often unnecessary) limitation is needed. Analysis methods are recommended which include very low penetration (infinite bus) as well as very high penetration (stand-alone) scenarios.

Hinrichsen, E. N.

1995-01-01

393

Thruster models for NEP system analysis  

NASA Technical Reports Server (NTRS)

There are currently no thruster modeling codes that can be integrated with power system codes for full propulsion system modeling. Most existing thruster models were written from a 'stand alone' viewpoint, assuming the user is performing analyses on thruster performance alone. The goal of the present modeling effort is to develop thruster codes that model performance and scaling as a function of mission and system inputs, rather than in terms of more elemental physical parameters. System level parameters of interest are as follows: performance, such as specific impulse and efficency; terminal characteristics, such as voltage or current; and mass. Specific impulse and efficiency couple with mission analyses, while terminal characteristics allow integration with power systems. Additional information on lifetime and operation may be required for detailed designs.

Gilland, Jim

1993-01-01

394

Power management of multi-hundred kilowatt spacecraft power systems  

NASA Astrophysics Data System (ADS)

A NASA-sponsored study of space power distribution system technology is in progress to develop an Autonomously Managed Power System (AMPS) for large space power platforms. The conceptual design of a 250 kW photovoltaic power system, including the power management subsystem (PMS), is presented. A PMS concept is derived based on the need to accommodate the increased complexity of a utility-type power system, and to minimize Shuttle resupply and ground station operational costs. The main PMS functions are discussed along with the control strategies of the autonomously managed power system.

Decker, D. K.; Fleck, G. W.; Graves, J.

395

Solar-Powered Refrigeration System  

NASA Technical Reports Server (NTRS)

A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure. and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

2001-01-01

396

Power system interface and umbilical system study  

NASA Technical Reports Server (NTRS)

System requirements and basic design criteria were defined for berthing or docking a payload to the 25 kW power module which will provide electrical power and attitude control, cooling, data transfer, and communication services to free-flying and Orbiter sortie payloads. The selected umbilical system concept consists of four assemblies and command and display equipment to be installed at the Orbiter payload specialist station: (1) a movable platen assembly which is attached to the power system with EVA operable devices; (2) a slave platen assembly which is attached to the payload with EVA operable devices; (3) a fixed secondary platen permanently installed in the power system; and (4) a fixed secondary platen permanently installed on the payload. Operating modes and sequences are described.

1980-01-01

397

Power Systems Advanced Research  

SciTech Connect

In the 17 quarters of the project, we have accomplished the following milestones - first, construction of the three multiwavelength laser scattering machines for different light scattering study purposes; second, build up of simulation software package for simulation of field and laboratory particulates matters data; third, carried out field online test on exhaust from combustion engines with our laser scatter system. This report gives a summary of the results and achievements during the project's 16 quarters period. During the 16 quarters of this project, we constructed three multiwavelength scattering instruments for PM2.5 particulates. We build up a simulation software package that could automate the simulation of light scattering for different combinations of particulate matters. At the field test site with our partner, Alturdyne, Inc., we collected light scattering data for a small gas turbine engine. We also included the experimental data feedback function to the simulation software to match simulation with real field data. The PM scattering instruments developed in this project involve the development of some core hardware technologies, including fast gated CCD system, accurately triggered Passively Q-Switched diode pumped lasers, and multiwavelength beam combination system. To calibrate the scattering results for liquid samples, we also developed the calibration system which includes liquid PM generator and size sorting instrument, i.e. MOUDI. In this report, we give the concise summary report on each of these subsystems development results.

California Institute of Technology

2007-03-31

398

Solar-powered cooling system  

DOEpatents

A solar-powered adsorption-desorption refrigeration and air conditioning system uses nanostructural materials made of high specific surface area adsorption aerogel as the adsorptive media. Refrigerant molecules are adsorbed on the high surface area of the nanostructural material. A circulation system circulates refrigerant from the nanostructural material to a cooling unit.

Farmer, Joseph C

2013-12-24

399

ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

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

M. Maniyar

2004-01-01

400

Power conditioning unit for photovoltaic power systems  

Microsoft Academic Search

Operational features and components of a power conditioning unit for interconnecting solar cell module powers with a utility grid are outlined. The two-stage unit first modifies the voltage to desired levels on an internal dc link, then inverts the current in 2 power transformers connected to a vector summation control to neutralize harmonic distortion up to the 11th harmonic. The

G. Beghin; V. T. Nguyen Phuoc

1981-01-01

401

Power Take-Off Systems  

Microsoft Academic Search

In this chapter the main mechanisms that can be implemented to convert wave into mechanical and\\/or electrical energy are discussed.\\u000a Such mechanisms are often called power take-off (PTO) or power conversion systems (the first is adopted throughout the book).\\u000a The review is directly linked with the most commonly used options and to those which are linked with the technologies described

Richard Curran; Matthew Folley; Oskar Danielsson; Karin Thorburn; Mats Leijon; Jamie Taylor

402

Impact of Power Generation Uncertainty on Power System Static Performance  

E-print Network

Impact of Power Generation Uncertainty on Power System Static Performance Yu Christine Chen, Xichen uncer- tainties on the generation side of power systems. We propose a method to assess whether static determined by the forecasted renewable power injection. In our methodology, the uncertainty in generation can

Liberzon, Daniel

403

Models for multimegawatt space power systems  

SciTech Connect

This report describes models for multimegawatt, space power systems which Sandia's Advanced Power Systems Division has constructed to help evaluate space power systems for SDI's Space Power Office. Five system models and models for associated components are presented for both open (power system waste products are exhausted into space) and closed (no waste products) systems: open, burst mode, hydrogen cooled nuclear reactor -- turboalternator system; open, hydrogen-oxygen combustion turboalternator system; closed, nuclear reactor powered Brayton cycle system; closed, liquid metal Rankine cycle system; and closed, in-core, reactor therminonic system. The models estimate performance and mass for the components in each of these systems. 17 refs., 8 figs., 15 tabs.

Edenburn, M.W.

1990-06-01

404

PSS Controller for Wind Power Generation Systems  

NASA Astrophysics Data System (ADS)

Small signal stability analysis for power systems with wind farm interaction is presented. Power systems oscillation modes can be excited by disturbance or fault in the grid. Variable speed wind turbines can be regulated to reduce these oscillations, stabilising the power system. A power system stabiliser (PSS) control loop for wind power is designed in order to increase the damping of the oscillation modes. The proposed power system stabiliser controller is evaluated by small signal analysis.

Domínguez-García, J. L.; Gomis-Bellmunt, O.; Bianchi, F.; Sumper, A.

2012-10-01

405

Nanosat Intelligent Power System Development  

NASA Technical Reports Server (NTRS)

NASA Goddard Space Flight Center is developing a class of satellites called nano-satellites. The technologies developed for these satellites will enable a class of constellation missions for the NASA Space Science Sun-Earth Connections theme and will be of great benefit to other NASA enterprises. A major challenge for these missions is meeting significant scientific- objectives with limited onboard and ground-based resources. Total spacecraft power is limited by the small satellite size. Additionally, it is highly desirable to minimize operational costs by limiting the ground support required to manage the constellation. This paper will describe how these challenges are met in the design of the nanosat power system. We will address the factors considered and tradeoffs made in deriving the nanosat power system architecture. We will discuss how incorporating onboard fault detection and correction capability yields a robust spacecraft power bus without the mass and volume penalties incurred from redundant systems and describe how power system efficiency is maximized throughout the mission duration.

Johnson, Michael A.; Beaman, Robert G.; Mica, Joseph A.; Truszkowski, Walter F.; Rilee, Michael L.; Simm, David E.

1999-01-01

406

A Nonlinear Digital Control Solution for a DC/DC Power Converter  

NASA Technical Reports Server (NTRS)

A digital Nonlinear Proportional-Integral-Derivative (NPID) control algorithm was proposed to control a 1-kW, PWM, DC/DC, switching power converter. The NPID methodology is introduced and a practical hardware control solution is obtained. The design of the controller was completed using Matlab (trademark) Simulink, while the hardware-in-the-loop testing was performed using both the dSPACE (trademark) rapid prototyping system, and a stand-alone Texas Instruments (trademark) Digital Signal Processor (DSP)-based system. The final Nonlinear digital control algorithm was implemented and tested using the ED408043-1 Westinghouse DC-DC switching power converter. The NPID test results are discussed and compared to the results of a standard Proportional-Integral (PI) controller.

Zhu, Minshao

2002-01-01

407

Computer Center: CIBE Systems.  

ERIC Educational Resources Information Center

Differentiates between computer systems and Computers in Biological Education (CIBE) systems (computer system intended for use in biological education). Describes several CIBE stand alone systems: single-user microcomputer; single-user microcomputer/video-disc; multiuser microcomputers; multiuser maxicomputer; and local and long distance computer…

Crovello, Theodore J.

1982-01-01

408

Model for energy conversion in renewable energy system with hydrogen storage  

NASA Astrophysics Data System (ADS)

A dynamic model for a stand-alone renewable energy system with hydrogen storage (RESHS) is developed. In this system, surplus energy available from a photovoltaic array and a wind turbine generator is stored in the form of hydrogen, produced via an electrolyzer. When the energy production from the wind turbine and the photovoltaic array is not enough to meet the load demand, the stored hydrogen can then be converted by a fuel cell to produce electricity. In this system, batteries are used as energy buffers or for short time storage. To study the behavior of such a system, a complete model is developed by integrating individual sub-models of the fuel cell, the electrolyzer, the power conditioning units, the hydrogen storage system, and the batteries (used as an energy buffer). The sub-models are valid for transient and steady state analysis as a function of voltage, current, and temperature. A comparison between experimental measurements and simulation results is given. The model is useful for building effective algorithms for the management, control and optimization of stand-alone RESHSs.

Kélouwani, S.; Agbossou, K.; Chahine, R.

409

Homopolar generator power supply system  

SciTech Connect

A high-energy, high-current homopolar generator pulsed power supply system that is compact and field portable. The power supply system includes a homopolar generator (HPG), an auxiliary supply and drive system, both mounted on a skid frame, and a control system coupled to the HPG and drive system. The homopolar generator has a split rotor with insulation between the halves and a recess in the periphery. A stator ring and field coil, for producing a magnetic field through which the rotor halves make two simultaneous voltage-generating passes, are disposed within the recess in the rotor. Air-actuated brush mechanisms inside and outside the recess contact surfaces of the rotor and collect discharge current. The auxiliary supply and drive system includes a motoring system comprising hydraulic motors for driving the HPG to speed, a bearing lubrication system, a generator for energizing the field coil, and a brush actuator air supply system, all of which are driven by a prime mover. The control system comprises a logic controller for executing a prescribed sequence of steps including turning on the prime mover, initiating motoring of the HPG, energizing the field coil, and initiating the discharge of electrical current.

Weldon, W. F.; Gully, J. H.

1985-10-01

410

2002CALIFORNIAPOWERMIX 2002 NET SYSTEM POWER CALCULATION  

E-print Network

Power Mix Fuel Type Net System Power Coal 15% Large Hydroelectric 23% Natural Gas 42% Nuclear 11CALIFORNIA ENERGY COMMISSION APRIL 2003 300-03-002 2002CALIFORNIAPOWERMIX 2002 NET SYSTEM POWER and report net system power, annually (Senate Bill 1305, Sher, Chapter 796, statue of 1997)1 . Net system

411

MEMS Rotary Engine Power System  

Microsoft Academic Search

This work presents a project overview and recent research results for the MEMS Rotary Engine Power System project at the Berkeley Sensor & Actuator Center of the University of California at Berkeley. The research motivation for the project is the high specific energy density of hydrocarbon fuels. When compared with the energy density of batteries, hydrocarbon fuels may have as

A. Carlos Fernandez-Pello; Albert P. Pisano; Kelvin Fu; David C. Walther; Aaron Knobloch; Fabian Martinez; Matt Senesky; Conrad Stoldt; Roya Maboudian; Seth Sanders; Dorian Liepmann

2003-01-01

412

Robotic monitoring of power systems  

Microsoft Academic Search

Monitoring of electric power systems in real time for reliability, aging status, and presence of incipient faults requires distributed and centralized processing of large amounts of data from distributed sensor networks. To solve this task, cohesive multidisciplinary efforts are needed from such fields as sensing, signal processing, control, communications, optimization theory, and, more recently, robotics. This review paper focuses on

Bing Jiang; Alexander Mamishev

2004-01-01

413

Analysis of Hybrid Power Systems  

Microsoft Academic Search

The paper contains the modelling of system comprising, the diesel generator, wind energy source, photovoltaic cell, solar power cells in source side domestic load, Industrial load in load side. The diesel generator is considered as a controlled energy source, and the wind is an uncontrolled energy source and the domestic load as an uncontrolled energy sink. All the components are

Vivek Venkoba Rao; Chellamuthu Chinnagounder

2007-01-01

414

Hydrocarbon fueled UUV power systems  

Microsoft Academic Search

Two hydrocarbon fueled internal combustion unmanned undersea vehicles (UUV) power sources incorporating a high-speed turbo-alternator are described, and their performance variation with operating depth and total energy is discussed. Turbine performance data is also discussed. These systems require only the refilling of tanks without disassembly between runs. They have overall system specific energies 3 to 4 times that of silver-zinc

D. H. Kiely; J. T. Moore

2002-01-01

415

Bonneville, Power Administration Timing System  

NASA Technical Reports Server (NTRS)

Time is an integral part of the Bonneville Power Administration's (BPA) operational systems. Generation and power transfers are planned in advance. Utilities coordinate with each other by making these adjustments on a timed schedule. Price varies with demand, so billing is based on time. Outages for maintenance are scheduled to assure they do not interrupt reliable power delivery. Disturbance records are aligned with recorded timetags for analysis and comparison with related information. Advanced applications like traveling wave fault location and real-time phase measurement require continuous timing with high precision. Most of BPA is served by a Central Time System (CTS) at the Dittmer Control Center near Portland, OR. This system keeps time locally and supplies time to both the control center systems and field locations via a microwave signal. It is kept synchronized to national standard time and coordinated with interconnected utilities. It is the official BPA time. Powwer system control and operation is described, followed by a description of BPA timing systems including CTS, the Fault Location Acquisition Reporter, time dissemination, and phasor measurements. References are provided for further reading.

Martin, Kenneth E.

1996-01-01

416

Power invariance transformation in power systems  

Microsoft Academic Search

Many textbooks describe a balanced three-phase circuit by a single-phase equivalent representation. Confusion may arise amongst students regarding per-unit values of line-to-line voltages and phase voltages and, therefore, about the magnitudes of currents and powers. This paper proposes that students must first be taught symmetrical components based on power invariance transformation. A balanced three-phase circuit is to be described only

J. Heydeman; W. W. Schongs

417

Solar energy power generation system  

SciTech Connect

A solar energy power generation system is described which consists of: (a) means for collecting and concentrating solar energy; (b) heat storage means; (c) Stirling engine means for producing power; (d) first heat transfer means for receiving the concentrated solar energy and for transferring heat to the heat storage means; and (e) second heat transfer means for controllably transferring heat from the storage means to the Stirling engine means and including a discharge heat pipe means for transferring heat to the Stirling engine means and further including means for inserting and withdrawing the discharge heat pipe means into and out of the heat storage means.

Nilsson, J.E.; Cochran, C.D.

1986-05-06

418

Introduction to Electric Power Systems  

NSDL National Science Digital Library

This fine course is offered as a welcome addition to MIT's OpenCourseWare initiative. The materials from this version of "Introduction to Electric Power Systems" are from the iteration taught by Professor James Kirtley in Spring 2011. On the site, visitors can look over the syllabus, the course calendar, readings, assignments, and quizzes. The topics covered here include load flow, power electric motor drives, and polyphase networks. The site also includes a number of problem sets, along with their accompanying solutions. Visitors can look over the readings and provide feedback on the course to the site administrators.

419

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

420

Electrical power systems for space station  

SciTech Connect

Major challenges in power system development are described. Evolutionary growth, operational lifetime, and other design requirements are discussed. A pictorial view of weightoptimized power system applications shows which systems are best for missions of various lengths and required power level. Following definition of the major elements of the electrical power system, an overview of element options and a brief technology assessment are presented. Selected trade-study results show end-to-end system efficiencies, required photovoltaic power capability as a function of energy storage system efficiency, and comparisons with other systems such as a solar dynamic power system.

Simon, W.E.

1984-08-01

421

Power management of hybrid photovoltaic - fuel cell power systems  

Microsoft Academic Search

Photovoltaic (PV) solar energy systems are widely used as an important alternative energy source. To overcome the problem of intermittent power generation, PV power systems may be integrated with other power sources. Fuel cells are an attractive option because of high efficiency, modularity and fuel flexibility; however, one main week point is their slow dynamics. On the other hand, current

Zhenhua Jiang

2006-01-01

422

Dynamic Isotope Power System, Integrated System Test  

NASA Astrophysics Data System (ADS)

The Dynamic Isotope Power System (DIPS) can supply three to four times more electrical power than Radioisotope Thermoelectric Generators (RTGs) for the same amount of Pu-238 fuel. The available electrical power can be used to drive propellant-efficient electric thrusters, which would enable and/or significantly enhance the capabilities of interplanetary missions. Because of this, the DIPS program has been reviewing the application of DIPS technology to the interplanetary missions in the 500 We to 1.0 kWe power range. Such a DIPS program would focus on completing an Integrated System Test (IST) of the DIPS in a simulated space environment. The DIPS IST would fully demonstrate DIPS integrated operation, long-term containment boundary integrity, and, most importantly, DIPS flight readiness. To reduce cost, schedule, and risk of the DIPS development, the design would use the DOE-developed Brayton Isotope Power System (BIPS) turboalternator compressor (TAC), which is currently being refurbished for use in the NASA-LeRC Solar Dynamic Ground Test Demonstration (SD GTD) Program. The DIPS IST, which would follow the SD GTD testing, would make use of common elements with the SD GTD wherever practical to reduce the IST cost and schedule. The components demonstrated in the IST would be flight prototypical except that full flight qualification would not be performed. For future interplanetary applications, the DIPS system would employ the identical TAC design demonstrated in the IST for all applications. Power level scalability would be achieved by scaling other loop components in a straightforward manner without technology development or requalification. This will significantly reduce costs while providing only a small scalability performance penalty.

Otting, William D.; Hunt, Maribeth E.; Ashe, Thomas L.

1994-07-01

423

An Analysis of Space Power System Masses  

Microsoft Academic Search

This paper analyzes various space electrical power system masses with particular emphasis on the power management and distribution (PMAD) portion. The electrical power system (EPS) is divided into functional blocks: source, interconnection, storage, transmission, distribution, system control and load. The PMAD subsystem is defined as all the blocks between the source, storage and load, plus the power conditioning equipment required

Barbara H. Kenny; Ronald C. Cull; M. David Kankam

1990-01-01

424

Global swing instability of multimachine power systems  

Microsoft Academic Search

This paper studies global instability in swing equations of multimachine power systems. Global instability is related to the undesirable phenomenon of power system, implying that most of all generators in a system coherently lose synchronism with the remaining generators of the system. By analyzing a power system with the loop transmission network, we analytically show that global instability can occur

Yoshihiko Susuki; Igor Mezic; Takashi Hikihara

2008-01-01

425

Multi-Mission Power Analysis Tool (MMPAT) Version 3  

NASA Technical Reports Server (NTRS)

The Multi-Mission Power Analysis Tool (MMPAT) simulates a spacecraft power subsystem including the power source (solar array and/or radioisotope thermoelectric generator), bus-voltage control, secondary battery (lithium-ion or nickel-hydrogen), thermostatic heaters, and power-consuming equipment. It handles multiple mission types including heliocentric orbiters, planetary orbiters, and surface operations. Being parametrically driven along with its user-programmable features can reduce or even eliminate any need for software modifications when configuring it for a particular spacecraft. It provides multiple levels of fidelity, thereby fulfilling the vast majority of a project s power simulation needs throughout the lifecycle. It can operate in a stand-alone mode with a graphical user interface, in batch mode, or as a library linked with other tools. This software can simulate all major aspects of a spacecraft power subsystem. It is parametrically driven to reduce or eliminate the need for a programmer. Added flexibility is provided through user-designed state models and table-driven parameters. MMPAT is designed to be used by a variety of users, such as power subsystem engineers for sizing power subsystem components; mission planners for adjusting mission scenarios using power profiles generated by the model; system engineers for performing system- level trade studies using the results of the model during the early design phases of a spacecraft; and operations personnel for high-fidelity modeling of the essential power aspect of the planning picture.

Wood, Eric G.; Chang, George W.; Chen, Fannie C.

2012-01-01

426

Study on photovoltaic power system on ships  

SciTech Connect

This paper presents the application of photovoltaic power systems to ships. Two types of leisure or fishing boats powered by photovoltaics are designed. The boats described are single hull and catamaran type with twin hulls. The design of a new electric power system using a photovoltaic power system in a harbor ship having 20 tons is also proposed. The results of this study show that the photovoltaic power system can apply to small ships.

Katagi, Takeshi; Fujii, Yoshimi; Nishikawa, Eiichi; Hashimoto, Takeshi [Kobe Univ. of Mercantile Marine (Japan)

1995-11-01

427

Advanced secondary power system for transport aircraft  

NASA Technical Reports Server (NTRS)

A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent.

Hoffman, A. C.; Hansen, I. G.; Beach, R. F.; Plencner, R. M.; Dengler, R. P.; Jefferies, K. S.; Frye, R. J.

1985-01-01

428

Radioisotope Power System Pool Concept  

NASA Technical Reports Server (NTRS)

Advanced Radioisotope Power Systems (RPS) for NASA deep space science missions have historically used static thermoelectric-based designs because they are highly reliable, and their radioisotope heat sources can be passively cooled throughout the mission life cycle. Recently, a significant effort to develop a dynamic RPS, the Advanced Stirling Radioisotope Generator (ASRG), was conducted by NASA and the Department of Energy, because Stirling based designs offer energy conversion efficiencies four times higher than heritage thermoelectric designs; and the efficiency would proportionately reduce the amount of radioisotope fuel needed for the same power output. However, the long term reliability of a Stirling based design is a concern compared to thermoelectric designs, because for certain Stirling system architectures the radioisotope heat sources must be actively cooled via the dynamic operation of Stirling converters throughout the mission life cycle. To address this reliability concern, a new dynamic Stirling cycle RPS architecture is proposed called the RPS Pool Concept.

Rusick, Jeffrey J.; Bolotin, Gary S.

2015-01-01

429

Power system dynamics influenced by a power electronic interface for variable speed wind energy conversion systems  

Microsoft Academic Search

A study of the influence of a wind energy conversion system on power system dynamics is presented in this paper. The wind energy conversion system is interfaced into a power system through a power electronic system including a voltage source converter (VSC) at the grid side. This paper investigates the system performance during a power system disturbance; a voltage sag

Z. Chen; Y. Hu

2004-01-01

430

Remote platform power conserving system  

NASA Technical Reports Server (NTRS)

A system is described where an unattended receiver and transmitter equipped data collection platform is interrogated by a substantially polar orbiting satellite. The method and apparatus involve physically representing the orbit of the satellite and the spin of the planetary body with timers, and using these representations to turn on the platform's receiver only when the satellite should be in radio range of the platform, whereby battery power at the platform is conserved.

Kurvin, C. W. (inventor)

1974-01-01

431

Stand-alone cage for posterior lumbar interbody fusion in the treatment of high-degree degenerative disc disease: design of a new device for an “old” technique. A prospective study on a series of 116 patients  

Microsoft Academic Search

Chronic lumbar pain due to degenerative disc disease affects a large number of people, including those of fully active age.\\u000a The usual self-repair system observed in nature is a spontaneous attempt at arthrodesis, which in most cases leads to pseudoarthrosis.\\u000a In recent years, many possible surgical fusion techniques have been introduced; PLIF is one of these. Because of the growing

Francesco Costa; Marco Sassi; Alessandro Ortolina; Andrea Cardia; Roberto Assietti; Alberto Zerbi; Martin Lorenzetti; Fabio Galbusera; Maurizio Fornari

2011-01-01

432

Systems Geobiology Powers of 10  

NSDL National Science Digital Library

The newly emerging field of Systems Geobiology requires linkage of biological processes with geological processes across broad scales of time (nanoseconds to eons) and space (nanometers to light years). Students are asked to specifically identify the scales of time and space across which Systems Geobiology research needs to be completed. They do this by making direct observations of a field photograph taken at Mammoth Hot Springs in Yellowstone National Park. Students then translate 10 of their observations onto Powers of 10 charts. This is followed by a class discussion of their results on topics such as: What is missing? How will these analyses be synthesized across such broad scales?

Bruce Fouke

433

78 FR 39280 - Integrated System Power Rates  

Federal Register 2010, 2011, 2012, 2013, 2014

...Southwestern markets power from 24 multi-purpose reservoir projects with hydroelectric power facilities constructed...and replacements in hydroelectric generating facilities...system. The Revised Power Repayment Study...

2013-07-01

434

Electrical power generating system. [for windpowered generation  

NASA Technical Reports Server (NTRS)

An alternating current power generation system adopted to inject power in an already powered power line is discussed. The power generating system solves to adjustably coup an induction motor, as a generator, to an ac power line wherein the motor and power line are connected through a triac. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced. The principal application will be for windmill powered generation.

Nola, F. J. (inventor)

1981-01-01

435

MEMS Rotary Engine Power System  

NASA Astrophysics Data System (ADS)

This work presents a project overview and recent research results for the MEMS Rotary Engine Power System project at the Berkeley Sensor & Actuator Center of the University of California at Berkeley. The research motivation for the project is the high specific energy density of hydrocarbon fuels. When compared with the energy density of batteries, hydrocarbon fuels may have as much as 20x more energy. However, the technical challenge is the conversion of hydrocarbon fuel to electricity in an efficient and clean micro engine. A 12.9 mm diameter Wankel engine will be shown that has already generated 4 Watts of power at 9300rpm. In addition, the 1mm and 2.4 mm Wankel engines that BSAC is developing for power generation at the microscale will be discussed. The project goal is to develop electrical power output of 90milliwatts from the 2.4 mm engine. Prototype engine components have already been fabricated and these will be described. The integrated generator design concept utilizes a nickel-iron alloy electroplated in the engine rotor poles, so that the engine rotor also serves as the generator rotor.

Fernandez-Pello, A. Carlos; Pisano, Albert P.; Fu, Kelvin; Walther, David C.; Knobloch, Aaron; Martinez, Fabian; Senesky, Matt; Stoldt, Conrad; Maboudian, Roya; Sanders, Seth; Liepmann, Dorian

436

Hybrid electric power generating system  

SciTech Connect

A hybrid power system is described which consists of: (a) a first energy converter operating on a closed Rankine cycle and including a vapor generator for vaporizing an organic working fluid in response to heat furnished from a heat source associated with the vapor generator. A turbogenerator is responsive to vaporized working fluid for generating electrical power and a condenser is responsive to vapor exhausted from the turbo-generator for converting such vapor to a condensed liquid. A means is included for returning the liquid to the vapor generator; (b) a second energy converter including a thermo-electric generator having a junction, a heat source for heating the junction whereby such thermo-electric generator generates electrical power; (c) a heat pipe for conveying heat from the heat source of the second converter to the vapor generator of the first converter and to the junction; and (d) means for applying the electrical power generated by the first and second converters to an electrical load.

Bronicki, L.Y.

1986-11-11

437

Visualizations for Power System Contingency Analysis Data  

E-print Network

and market analyses to show potential problems with the system. Due to the tremendous and yet increasing power system and power market analyses, such as ATC evaluation, security assessment and transaction whether the system is secure. With the global trend towards deregulation in the power system industry

438

SITE ELECTRICAL POWER SYSTEM DESCRIPTION DOCUMENT  

Microsoft Academic Search

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

E. P. McCann

1999-01-01

439

System and method for advanced power management  

DOEpatents

A power management system is provided that includes a power supply means comprising a plurality of power supply strings, a testing means operably connected to said plurality of power supply strings for evaluating performance characteristics of said plurality of power supply strings, and a control means for monitoring power requirements and comprising a switching means for controlling switching of said plurality of power supply strings to said testing means.

Atcitty, Stanley (Albuquerque, NM); Symons, Philip C. (Surprise, AZ); Butler, Paul C. (Albuquerque, NM); Corey, Garth P. (Albuquerque, NM)

2009-07-28

440

Artificial Intelligence and Spacecraft Power Systems  

NASA Technical Reports Server (NTRS)

This talk will present the work which has been done at NASA Marshall Space Flight Center involving the use of Artificial Intelligence to control the power system in a spacecraft. The presentation will include a brief history of power system automation, and some basic definitions of the types of artificial intelligence which have been investigated at MSFC for power system automation. A video tape of one of our autonomous power systems using co-operating expert systems, and advanced hardware will be presented.

Dugel-Whitehead, Norma R.

1997-01-01

441

Device system and method for miniaturized radiation spectrometer  

NASA Technical Reports Server (NTRS)

A device/system for radiation sensing is configured to detect high and low LET radiation. The radiation sensing system may include a high LET detector and a low LET detector coupled to the high LET detector by a CPU, wherein the high LET detector and the low LET detector are assembled within a single unit. The device/system may also include a high LET and low LET detector that may be coupled together without an internal CPU. Overall, the device/system may be a stand-alone system and/or coupled to an external processing device. The device/system may also be approximately 6.times.6.times.2 cm.sup.3 in size, making it hand portable and may weigh less or equal to approximately ninety (90) grams, and operate on less than or approximately 0.25 watts of power.

Stassinopoulos, Epaminondas G. (Inventor)

2008-01-01

442

TPV Power Source Using Infrared-Sensitive Cells with Commercially Available Radiant Tube Burner  

NASA Astrophysics Data System (ADS)

Over the last several years, JX Crystals has invented and systematically developed the key components for thermophotovoltaic systems. These key components include GaSb infrared sensitive cells, high power density shingle circuits, dielectric filters, and hydrocarbon-fueled radiant tube burners. Most recently, we invented and demonstrated an antireflection (AR)-coated tungsten IR emitter which when integrated with the other key components should make TPV systems with efficiencies over 10% practical. However, the use of the AR tungsten emitter requires an oxygen-free hermetic seal enclosure. During a 2003 Small Business Innovative Research (SBIR) Phase I contract, we integrated a tungsten emitter foil and a commercial SiC radiant tube burner within an emitter thermos and successfully demonstrated its operation at high temperature. We also designed a complete stand alone 500 W TPV generator. During the upcoming SBIR Phase II, we plan to implement this design in hardware.

Fraas, Lewis; Minkin, Leonid; Hui, She; Avery, James; Howells, Christopher

2004-11-01

443

Nuclear power plant computer replacement  

SciTech Connect

Consumers Power Company (CPCo) has recently completed an ambitious project to replace the non-safety-related plant process computer for the Palisades Nuclear Plant. The replacement computer retains the functions of the old plant computer system with minor exceptions. However, the architecture of the new computer system is vastly improved from the old plant computer. The hardware and software components of the new computer system are the state of the art. The old system consisted of five stand-alone computers, each performing their intended function separately. The new architecture employs a number of computing and data acquisition nodes networked together to gather, share, process, present, and store data more efficiently. For cost efficiency, some of the old hardware, such as the Critical Functions Monitoring System multiplexer, has been retained. The new computer system has a significantly higher availability, and lower maintenance cost. It performs certain functions that were not possible with the old system, such as real-time validation of rod position monitored by the Plant Information Processor and the Secondary Position Indicator. While the new computer system is more capable, more reliable, more user friendly, and easier to maintain, taking it to operability status presented CPCo with some new and challenging issues.

Stevens, K. [Consumers Power Co., Covert, MI (United States). Palisades Nuclear Plant; Raychaudhuri, R. [Sargent and Lundy, Chicago, IL (United States)

1996-11-01

444

Molecular mechanics and dynamics characterization of an in silico mutated protein: a stand-alone lab module or support activity for in vivo and in vitro analyses of targeted proteins.  

PubMed

Over the past 20 years, the biological sciences have increasingly incorporated chemistry, physics, computer science, and mathematics to aid in the development and use of mathematical models. Such combined approaches have been used to address problems from protein structure-function relationships to the workings of complex biological systems. Computer simulations of molecular events can now be accomplished quickly and with standard computer technology. Also, simulation software is freely available for most computing platforms, and online support for the novice user is ample. We have therefore created a molecular dynamics laboratory module to enhance undergraduate student understanding of molecular events underlying organismal phenotype. This module builds on a previously described project in which students use site-directed mutagenesis to investigate functions of conserved sequence features in members of a eukaryotic protein kinase family. In this report, we detail the laboratory activities of a MD module that provide a complement to phenotypic outcomes by providing a hypothesis-driven and quantifiable measure of predicted structural changes caused by targeted mutations. We also present examples of analyses students may perform. These laboratory activities can be integrated with genetics or biochemistry experiments as described, but could also be used independently in any course that would benefit from a quantitative approach to protein structure-function relationships. PMID:24259335

Chiang, Harry; Robinson, Lucy C; Brame, Cynthia J; Messina, Troy C

2013-01-01

445

The design of the NEPTUNE power system  

Microsoft Academic Search

The proposed NEPTUNE observatory will include about 30 locations on the Juan de Fuca plate where scientific instruments can be connected for communication and power. The NEPTUNE power system is required to make available at each location the largest amount of power possible, using conventional submarine telecommunications cable. The power delivery system is based on the use of a standard

Harold Kirkham; Bruce M. Howeb; Vatché Vorpérian; Paul Bowerman

2001-01-01

446

Autonomous power system intelligent diagnosis and control  

NASA Technical Reports Server (NTRS)

The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution hardware. Knowledge-based software provides a robust method of control for highly complex space-based power systems that conventional methods do not allow. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis and control, the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space based power system. The operation of the Autonomous Power System as a whole is described and the responsibilities of the three elements - APEX, AIPS, and Brassboard - are characterized. A discussion of the methodologies used in each element is provided. Future plans are discussed for the growth of the Autonomous Power System.

Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony

1991-01-01

447

Autonomous Power System intelligent diagnosis and control  

NASA Technical Reports Server (NTRS)

The Autonomous Power System (APS) project at NASA Lewis Research Center is designed to demonstrate the abilities of integrated intelligent diagnosis, control, and scheduling techniques to space power distribution hardware. Knowledge-based software provides a robust method of control for highly complex space-based power systems that conventional methods do not allow. The project consists of three elements: the Autonomous Power Expert System (APEX) for fault diagnosis and control, the Autonomous Intelligent Power Scheduler (AIPS) to determine system configuration, and power hardware (Brassboard) to simulate a space based power system. The operation of the Autonomous Power System as a whole is described and the responsibilities of the three elements - APEX, AIPS, and Brassboard - are characterized. A discussion of the methodologies used in each element is provided. Future plans are discussed for the growth of the Autonomous Power System.

Ringer, Mark J.; Quinn, Todd M.; Merolla, Anthony

1991-01-01

448

Estimating the incidence, prevalence and true cost of asthma in the UK: secondary analysis of national stand-alone and linked databases in England, Northern Ireland, Scotland and Wales—a study protocol  

PubMed Central

Introduction Asthma is now one of the most common long-term conditions in the UK. It is therefore important to develop a comprehensive appreciation of the healthcare and societal costs in order to inform decisions on care provision and planning. We plan to build on our earlier estimates of national prevalence and costs from asthma by filling the data gaps previously identified in relation to healthcare and broadening the field of enquiry to include societal costs. This work will provide the first UK-wide estimates of the costs of asthma. In the context of asthma for the UK and its member countries (ie, England, Northern Ireland, Scotland and Wales), we seek to: (1) produce a detailed overview of estimates of incidence, prevalence and healthcare utilisation; (2) estimate health and societal costs; (3) identify any remaining information gaps and explore the feasibility of filling these and (4) provide insights into future research that has the potential to inform changes in policy leading to the provision of more cost-effective care. Methods and analysis Secondary analyses of data from national health surveys, primary care, prescribing, emergency care, hospital, mortality and administrative data sources will be undertaken to estimate prevalence, healthcare utilisation and outcomes from asthma. Data linkages and economic modelling will be undertaken in an attempt to populate data gaps and estimate costs. Separate prevalence and cost estimates will be calculated for each of the UK-member countries and these will then be aggregated to generate UK-wide estimates. Ethics and dissemination Approvals have been obtained from the NHS Scotland Information Services Division's Privacy Advisory Committee, the Secure Anonymised Information Linkage Collaboration Review System, the NHS South-East Scotland Research Ethics Service and The University of Edinburgh's Centre for Population Health Sciences Research Ethics Committee. We will produce a report for Asthma-UK, submit papers to peer-reviewed journals and construct an interactive map. PMID:25371419

Mukherjee, Mome; Gupta, Ramyani; Farr, Angela; Heaven, Martin; Stoddart, Andrew; Nwaru, Bright I; Fitzsimmons, Deborah; Chamberlain, George; Bandyopadhyay, Amrita; Fischbacher, Colin; Dibben, Christopher; Shields, Michael; Phillips, Ceri; Strachan, David; Davies, Gwyneth; McKinstry, Brian; Sheikh, Aziz

2014-01-01

449

Solid state remote power controllers for 120 VDC power systems  

NASA Technical Reports Server (NTRS)

Solid state remote power controllers can be applied to any dc power system up to 120 Vdc and distribute power up to 3.6 kW per hour. Devices have demonstrated total electrical efficiencies of 98.5 percent to 99.0 percent at rated load currents.

Sundberg, G. R.; Baker, D. E.

1975-01-01

450

Impacts of large scale wind power integration on power system  

Microsoft Academic Search

In China, many of the best resources for wind generation are located far away from load centers. Large generating facilities connected to distant load centers by long AC transmission lines face numerous technical challenges. Oriented by the current state and development of wind power generation in China, impacts of large scale wind power integration on power system are addressed in

Yanhua Liu; Yongning Chi; Weisheng Wang; Huizhu Dai

2011-01-01

451

Small Solar Power Systems /SSPS/  

NASA Astrophysics Data System (ADS)

A detailed description is given of the project organization, hardware, and projected performance of the distributed collector and central receiver solar thermal research facilities comprising the Small Power Systems (SSPS) plants in Almeria, Spain. The Distributed Collector System (DCS) is rated at 500 kWe and employs two fields of line-focusing parabolic trough collectors. The Central Receiver System (CRS) has the same rating and uses liquid sodium as a heat-transfer medium to circulate the 530 C heat yielded by a concentration factor of 450 from 4000 sq m of reflective surface. The purpose of the plant's dual configuration is the comparison of the two concentration methods under identical environmental conditions and the responsibility of a single operator/evaluator.

Grasse, W.

1981-05-01

452

Uninterruptible power supply (UPS) systems  

SciTech Connect

Use of this purchase specification is not mandatory. User should review the document and determine if it meets the user`s purpose. This document contains a fill-in-the-blanks guide specification for the procurement of uninterruptible power supply (UPS) systems greater than 10 kVA, organized as follows: Parts 1 through 7--technical requirements; Appendix A--technical requirements to be included in the proposal; Appendix B--UPS system data sheets to be completed by each bidder (Seller) and submitted with the proposal; Appendix C--general guidelines giving the specifier parameters for selecting a UPS system; it should be read before preparing an actual specification, and is not attached to the specification; Attachment 1--sketches prepared by the purchaser (Owner); Attachment 2--sample title page.

NONE

1997-04-01

453

Operation experience of a solar- and wind-powered desalination demonstration plant  

Microsoft Academic Search

The present work outlines the designing, erection and operation process of a stand-alone desalination plant powered by both solar photovoltaic and wind energy. Such a plant will serve small isolated communities in remote areas devoid of water resources. A specially customized code was built to simulate the operation of the installation in order to allow appropriate choice of components specifications.

Dan Weiner; David Fisher; Eduard J. Moses; Baruch Katz; Giora Meron

2001-01-01

454

Design and Control of A Low Power DC-DC Converter fed by a Photovoltaic array  

Microsoft Academic Search

In this paper, we present a DC-DC converter fed by a PV array for stand alone applications up to 50 W. It is dedicated to rural areas in countries having abundant sunshine and where there is no grid connection to the utility network or the power supply is weak as in many underdeveloped countries. Using a single PV array of

D. Diallo; F. Belkacem; E. Berthelot

2007-01-01

455

25 kW solar photovoltaic flat panel power supply for an electrodialysis water desalination unit in New Mexico. Final report, 1 October 1978-31 May 1979  

SciTech Connect

The stand-alone system designed by Mobil Tyco Solar Energy Corporation consists of a 25 kW flat panel array employing silicon ribbon solar cells, used in conjunction with a lead-acid battery bank to provide the complete power requirements of an electrodialysis water desalination unit. The Mobil Tyco system design is intended to be prototypical of part of the drinking water supply for a remote village. The specific task which this system will perform during Phase III is to aid in the restoration of an aquifer following a uranium leaching operation by the Energy Minerals Division of Mobil Oil Corporation at a site which is approximately four miles from the township of Crownpoint in northwestern New Mexico. System design is described, and a detailed description of a mathematical model and computerized simulation of the system is included. (WHK)

Wood, J.R.; Crutcher, J.L.

1980-06-01

456

Wind Speed Forecasting for Power System Operation  

E-print Network

In order to support large-scale integration of wind power into current electric energy system, accurate wind speed forecasting is essential, because the high variation and limited predictability of wind pose profound challenges to the power system...

Zhu, Xinxin

2013-07-22

457

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

458

Dc power supplies and hard-tube power conditioning systems  

SciTech Connect

In this lecture, we shall discuss some of the major characteristics of dc power supplies and hard-tube pulsers, along with many of their PCS limiting properties and several of the more powerful vacuum tubes that are currently available for larger hard-tube pulsers systems. The initial topic will be elementary dc power supplies, operating with standard 60 Hz AC input power. The full-wave bridge design will be discussed in detail, illustrating the majority of the significant circuit parameters.

Sarjeant, W.J.

1980-01-01

459

Heat and Power Systems Design  

E-print Network

specifications and not analyzed to determine whether they can be reduced or altered. The basis for selecting a cogeneration system should not be limited to the power-to-heat ratio, the fuel-use efficiency or the incremental heat rate. Rather, the analysis.... The exothermic heat of reaction is removed by a hot oil belt which is used to reboil the adjacent stripper. Hot utility, QH' is applied to the fractionator reboiler by means of 515 psig steam from the central boiler house. Examination of this process...

Spriggs, H. D.; Shah, J. V.

460

Bulk power system reliability assessment considering protection system hidden failures  

Microsoft Academic Search

In power system planning and operation procedures, bulk power system reliability assessment plays an important role. The current practice of such assessment generally assumes that protection systems are perfect, and the effects of protection system hidden failures are ignored. Recent research, however, shows that protection system hidden failures have been recognized as a contributing factor to power system cascading outages.

Fang Yang; A. P. Sakis Meliopoulos; George J. Cokkinides; Q. Binh Dam

2007-01-01

461

Impact of Security on Power Systems Operation  

Microsoft Academic Search

This paper reviews the status of security analyses in vertically integrated utilities and discusses the impact of system security on the operation and the planning of restructured power systems. The paper is focused on the static security rather than the dynamic security of power systems. The paper also discusses assumptions, functions, and calculation tools that are considered for satisfying power

MOHAMMAD SHAHIDEHPOUR; F. Tinney; Yong Fu

2005-01-01

462

Options for Affordable Fission Surface Power Systems  

NASA Technical Reports Server (NTRS)

Fission surface power systems could provide abundant power anywhere on free surface of the moon or Mars. Locations could include permanently shaded regions on the moon and high latitudes on Mars. To be fully utilized; however, fission surface power systems must be safe, have adequate performance, and be affordable. This paper discusses options for the design and development of such systems.

Houts, Mike; Gaddis, Steve; Porter, Ron; VanDyke, Melissa; Martin Jim; Godfroy, Tom; Bragg-Sitton, Shannon; Garber, Anne; Pearson, Boise

2006-01-01

463

Wind Power Systems 1.0 Overview  

E-print Network

Wind Power Systems 1.0 Overview 2.0 Simulation model for wind farm operation 3.0 Research topics #12;Contents 1. Overview of wind power systems 2. Simulation model of wind farm operations 3. Research area of wind power systems 3.0 Overview 3.1 Economic dispatch 3.2 Correlation analysis 3.3 Energy

Ding, Yu

464

Security schemes of power systems against blackouts  

Microsoft Academic Search

A security scheme of the power systems should protect the integrity of the electric networks and carry out fast operations on the entire power system to prevent a possible blackout. Blackouts started as local failures led to electrical disturbances, and the complete collapse of the power systems. This work proposes a security scheme based in two stages. In the first

R. Moreno; M. A. Rios; A. Torres

2010-01-01

465

Laser power conversion system analysis, volume 1  

NASA Technical Reports Server (NTRS)

The orbit-to-orbit laser energy conversion system analysis established a mission model of satellites with various orbital parameters and average electrical power requirements ranging from 1 to 300 kW. The system analysis evaluated various conversion techniques, power system deployment parameters, power system electrical supplies and other critical supplies and other critical subsystems relative to various combinations of the mission model. The analysis show that the laser power system would not be competitive with current satellite power systems from weight, cost and development risk standpoints.

Jones, W. S.; Morgan, L. L.; Forsyth, J. B.; Skratt, J. P.

1979-01-01

466

Aircraft Fuel Cell Power Systems  

NASA Technical Reports Server (NTRS)

In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results when it is finally ready for testing. Another of my goals is to test new membranes for use in proton-exchange membrane fuel cells, in the hope that these membranes can increase the electricity that is produced by he1 cells. Producing more electricity means that fewer fuel cells are needed, thus reducing the weight and volume of an APU based on fuel cells, making such an APU much more viable.

Needham, Robert

2004-01-01

467

Automated load management for spacecraft power systems  

NASA Technical Reports Server (NTRS)

An account is given of the results of a study undertaken by NASA's Marshall Space Flight Center to design and implement the load management techniques for autonomous spacecraft power systems, such as the Autonomously Managed Power System Test Facility. Attention is given to four load-management criteria, which encompass power bus balancing on multichannel power systems, energy balancing in such systems, power quality matching of loads to buses, and contingency load shedding/adding. Full implementation of these criteria calls for the addition of a second power channel.

Lollar, Louis F.

1987-01-01

468

45 CFR 155.1065 - Stand-alone dental plans.  

Code of Federal Regulations, 2012 CFR

...REQUIREMENTS RELATING TO HEALTH CARE ACCESS EXCHANGE...STANDARDS UNDER THE AFFORDABLE CARE ACT Exchange Functions...Certification of Qualified Health Plans § 155...dental essential health benefit as defined...J) of the Affordable Care Act, provided...

2012-10-01

469

45 CFR 155.1065 - Stand-alone dental plans.  

Code of Federal Regulations, 2014 CFR

...REQUIREMENTS RELATING TO HEALTH CARE ACCESS EXCHANGE...STANDARDS UNDER THE AFFORDABLE CARE ACT Exchange Functions...Certification of Qualified Health Plans § 155...dental essential health benefit as defined...J) of the Affordable Care Act, provided...

2014-10-01

470

45 CFR 155.1065 - Stand-alone dental plans.  

Code of Federal Regulations, 2013 CFR

...REQUIREMENTS RELATING TO HEALTH CARE ACCESS EXCHANGE...STANDARDS UNDER THE AFFORDABLE CARE ACT Exchange Functions...Certification of Qualified Health Plans § 155...dental essential health benefit as defined...J) of the Affordable Care Act, provided...

2013-10-01

471

Developing a Stand Alone Sun Photometer for Ships and Buoys  

NASA Technical Reports Server (NTRS)

During November and December 1995 the first Aerosol Characterization Experiment (ACE 1) was carried to characterize the aerosol physical and optical properties in the clean marine atmosphere near Tasmania in the South Pacific. As part of this effort, and with funding from this proposal, we installed a sun photometer on the R/V Discoverer and a spectro-photometer on the NOAA C-130 aircraft.

Porter, John N.

1997-01-01

472

29 CFR 778.104 - Each workweek stands alone.  

Code of Federal Regulations, 2010 CFR

...he must receive overtime compensation for the overtime...and employees paid on a commission basis. It is therefore...the hours worked and the compensation earned by pieceworkers and commission employees on a weekly...

2010-07-01

473

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

474

Power system characteristics for more electric aircraft  

NASA Technical Reports Server (NTRS)

It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.

Hansen, Irving G.

1993-01-01

475

Integration of stochastic generation in power systems  

Microsoft Academic Search

Stochastic generation, i.e., electrical power production by an uncontrolled primary energy source, is expected to play an important role in future power systems. A new power system structure is created due to the large-scale implementation of this small-scale, distributed, non-dispatchable generation; the ‘horizontally-operated’ system. Modeling methodologies that can deal with the operational uncertainty introduced by these power units should be

G. Papaefthymiou; P. H. Schavemaker; L. van der Sluis; W. L. Kling; D. Kurowicka; R. M. Cooke

2006-01-01

476

Tailoring SCADA systems for standby power applications  

SciTech Connect

Supervisory control and data acquisition (SCADA) systems have been used by the manufacturing and process industries and many electric power utilities for energy management systems, including economic dispatch and the interconnection processing of energy. However, the use of SCADA in smaller power generation systems is not quite so wide spread. This article explains how a SCADA system was custom developed for a stand-by power generation system recently installed in a commercial office building.

Leslie, D.; Hlushko, A.; Abughazaleh, S.; Garza, F.

1994-04-01

477

Next generation cooled long range thermal sights with minimum size, weight, and power  

NASA Astrophysics Data System (ADS)

Situational awareness and precise targeting at day, night and severe weather conditions are key elements for mission success in asymmetric warfare. To support these capabilities for the dismounted soldier, AIM has developed a family of stand-alone thermal weapon sights based on high performance cooled IR-modules which are used e.g. in the infantryman of the future program of the German army (IdZ). The design driver for these sights is a long ID range <1500m for the NATO standard target to cover the operational range of a platoon with the engagement range of .50 cal rifles, 40mm AGLs or for reconnaissance tasks. The most recent sight WBZG has just entered into serial production for the IdZ enhanced system of the German army with additional capabilities like a wireless data link to the soldier backbone computer. Minimum size, weight and power (SWaP) are most critical requirements for the dismounted soldiers' equipment and sometimes push a decision towards uncooled equipment with marginal performance referring to the outstanding challenges in current asymmetric warfare, e.g. the capability to distinguish between combatants and non-combatants in adequate ranges. To provide the uncompromised e/o performance with SWaP parameters close to uncooled, AIM has developed a new thermal weapon sight based on high operating temperature (HOT) MCT MWIR FPAs together with a new low power single piston stirling cooler. In basic operation the sight is used as a clip-on in front of the rifle scope. An additional eyepiece for stand-alone targeting with e.g. AGLs or a biocular version for relaxed surveillance will be available. The paper will present details of the technologies applied for such long range cooled sights with size, weight and power close to uncooled.

Breiter, R.; Ihle, T.; Wendler, J.; Rühlich, I.; Ziegler, J.

2013-06-01

478

Low power systems for wireless microsensors  

Microsoft Academic Search

Low power wireless sensor networks pro- vide a new monitoring and control capability for civil and military applications in transportation, manufactur- ing, biomedical, environmental management, and safety and security systems. Wireless microsensor network nodes, operating at average and peak power levels con- strained by compact power sources, offer a range of important challenges for low power methods. This paper reports

K. Bult; Amit Burstein; D. Chang; Michael J. Dong; M. Fielding; E. Kruglick; J. Ho; F. Lin; T. H. Lin; William J. Kaiser; H. Marcy; R. Mukai; Phyllis R. Nelson; F. L. Newburg; Kristofer S. J. Pister; Gregory J. Pottie; Henry Sanchez; Oscar M. Stafsudd; K. Tan; S. Xue; J. Yao

1996-01-01

479

Power Control Algorithms for Satellite Communication Systems  

Microsoft Academic Search

Three different ground terminal transmit power control concepts for a Satcom system are examined. The effectiveness of constant satellite power (CSP) sharing among the carriers and adaptive satellite power (ASP) sharing is compared with constant ground terminal transmit power (CTP). It is shown that ASP offers substantial advantages over CSP in combating environmental degradations and that both can increase link

A. Ince; D. Brown; J. Midgley

1976-01-01

480

POWER GRID DYNAMICS: ENHANCING POWER SYSTEM OPERATION THROUGH PRONY ANALYSIS  

SciTech Connect

Prony Analysis is a technique used to decompose a signal into a series consisting of weighted complex exponentials and promises to be an effi cient way of recognizing sensitive lines during faults in power systems such as the U.S. Power grid. Positive Sequence Load Flow (PSLF) was used to simulate the performance of a simple two-area-four-generator system and the reaction of the system during a line fault. The Dynamic System Identifi cation (DSI) Toolbox was used to perform Prony analysis and use modal information to identify key transmission lines for power fl ow adjustment to improve system damping. The success of the application of Prony analysis methods to the data obtained from PSLF is reported, and the key transmission line for adjustment is identifi ed. Future work will focus on larger systems and improving the current algorithms to deal with networks such as large portions of the Western Electricity Coordinating Council (WECC) power grid.

Ray, C.; Huang, Z.

2007-01-01

481

Grid-Tied Photovoltaic Power System  

NASA Technical Reports Server (NTRS)

A grid-tied photovoltaic (PV) power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. Operating costs of a PV power system are low compared to conventional power technologies. This method can displace the highest-cost electricity during times of peak demand in most climatic regions, and thus reduce grid loading. Net metering is often used, in which independent power producers such as PV power systems are connected to the utility grid via the customers main service panels and meters. When the PV power system is generating more power than required at that location, the excess power is provided to the utility grid. The customer pays the net of the power purchased when the on-site power demand is greater than the onsite power production, and the excess power is returned to the utility grid. Power generated by the PV system reduces utility demand, and the surplus power aids the community. Modern PV panels are readily available, reliable, efficient, and economical, with a life expectancy of at least 25 years. Modern electronics have been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy equal to the modern PV panels. The grid-tied PV power system was successfully designed and developed, and this served to validate the basic principles developed, and the theoretical work that was performed. Grid-tied PV power systems are reliable, maintenance- free, long-life power systems, and are of significant value to NASA and the community. Of particular value are the analytical tools and capabilities that have been successfully developed. Performance predictions can be made confidently for grid-tied PV systems of various scales. The work was done under the NASA Hybrid Power Management (HPM) Program, which is the integration of diverse power devices in an optimal configuration for space and terrestrial applications.

Eichenberg, Dennis J.

2011-01-01

482

Environmental Control and Life Support Systems and Power Systems ...  

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

Environmental Control and Life Support Systems and Power Systems - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

483

Power-Invariant Magnetic System Modeling  

E-print Network

POWER-INVARIANT MAGNETIC SYSTEM MODELING A Dissertation by GUADALUPE GISELLE GONZALEZ DOMINGUEZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of DOCTOR OF PHILOSOPHY August 2011 Major Subject: Electrical Engineering Power-Invariant Magnetic System Modeling Copyright 2011 Guadalupe Giselle González Domínguez POWER-INVARIANT MAGNETIC...

Gonzalez Dominguez, Guadalupe Giselle

2012-10-19

484

14 CFR 27.695 - Power boost and power-operated control system.  

Code of Federal Regulations, 2010 CFR

...Power boost and power-operated control system. 27.695 Section 27.695...ROTORCRAFT Design and Construction Control Systems § 27.695 Power boost and power-operated control system. (a) If a power boost...

2010-01-01

485

14 CFR 29.695 - Power boost and power-operated control system.  

Code of Federal Regulations, 2010 CFR

...Power boost and power-operated control system. 29.695 Section 29.695...ROTORCRAFT Design and Construction Control Systems § 29.695 Power boost and pow