WorldWideScience

Sample records for conversion systems funded

  1. Analysis of the performance and cost effectiveness of nine small wind energy conversion systems funded by the DOE small grants program

    Energy Technology Data Exchange (ETDEWEB)

    Kay, Joshua [Univ. of California, Berkeley, CA (United States)

    1982-04-01

    This report presents an analysis of the technical performance and cost effectiveness of nine small wind energy conversion systems (SWECS) funded during FY 1979 by the U.S. Department of Energy. Chapter 1 gives an analytic framework with which to evaluate the systems. Chapter 2 consists of a review of each of the nine projects, including project technical overviews, estimates of energy savings, and results of economic analysis. Chapter 3 summarizes technical, economic, and institutional barriers that are likely to inhibit widespread dissemination of SWECS technology.

  2. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  3. Wind energy conversion system

    Science.gov (United States)

    Longrigg, Paul

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  4. Energy conversion system

    Science.gov (United States)

    Murphy, L.M.

    1985-09-16

    The energy conversion system includes a photo-voltaic array for receiving solar radiation and converting such radiation to electrical energy. The photo-voltaic array is mounted on a stretched membrane that is held by a frame. Tracking means for orienting the photo-voltaic array in predetermined positions that provide optimal exposure to solar radiation cooperate with the frame. An enclosure formed of a radiation transmissible material includes an inside containment space that accommodates the photo-voltaic array on the stretched membrane, the frame and the tracking means, and forms a protective shield for all such components. The enclosure is preferably formed of a flexible inflatable material and maintains its preferred form, such as a dome, under the influence of a low air pressure furnished to the dome. Under this arrangement the energy conversion system is streamlined for minimizing wind resistance, sufficiently weathproof for providing protection against weather hazards such as hail, capable of using diffused light, lightweight for low-cost construction and operational with a minimal power draw.

  5. South African pension fund conversions: Dealing with environmental change

    Directory of Open Access Journals (Sweden)

    D. T. George

    2007-12-01

    Full Text Available Purpose: The purpose of this paper is to analyse South African pension fund conversions from defined benefit to defined contribution structures and to develop a model for dealing with environmental change. Design/Methodology/Approach: Qualitative research methodology was used. Industry experts were interviewed to obtain a macro view of the phenomenon and specific manifestations of the phenomenon were also considered in case studies.Feedback from semi-structured interviews was categorised into several emergent themes. Within-case and cross-case analyses were conducted. Findings: Results indicated that an environmental shock exerted a substantial influence on the course of events. Under these: • Various factors combined to drive organisational evolution (i.e. adaptation to the environment. • Adaptation speed was inappropriate and exceeded that which was required for sufficient thought. • Uncertainty and vacuum circumstances arose leading to consequences that require redress. • The relative power of the stakeholders changed and influenced the strategic outcome. • An imbalance in stakeholder interests arose and ethical factors became consequential. • Business acted to restore certainty for itself. Implications: This paper provides insight into organisational behaviour during periods of environmental shock. Environmental shock can be defined as "a condition that arises where business or societal rules are inadequate, or do not exist, to deal with unfolding events". An environmental shock has greater magnitude than a competitive shock, and can include several competitive shocks. Originality/Value: Analysis of pension fund conversions revealed organisational behaviour during periods of environmental shock and the emerging model can be applied in other instances of environmental shock, such as broad-based black economic empowerment (B-B BEE, land redistribution, sanctions and constitutional development.

  6. HYDROKINETIC ENERGY CONVERSION SYSTEMS: PROSPECTS ...

    African Journals Online (AJOL)

    eobe

    hydro-to-electric power system, which is being strongly recognized as a unique and unconventional renewable energy solution, is the marine and hydrokinetic energy conversion technology [8]. Hydrokinetic (In Stream, or water current) energy conversion implies the utilization of the kinetic energy of rivers, streams, tidal ...

  7. Biological conversion system

    Science.gov (United States)

    Scott, C.D.

    A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

  8. Photovoltaic Energy Conversion Systems

    DEFF Research Database (Denmark)

    Kouro, Samir; Wu, Bin; Abu-Rub, Haitham

    2014-01-01

    This chapter presents a comprehensive overview of grid-connected PV systems, including power curves, grid-connected configurations, different converter topologies (both single- and three-phase), control schemes, MPPT, and anti-islanding detection methods. The focus of the chapter has been on the ...

  9. Offshore wind energy conversion systems

    Science.gov (United States)

    Kilar, L. A.; Stiller, P. H.; Anacona, D. F.

    The paper summarizes the findings of a comprehensive assessment of off-shore wind energy conversion systems. Eight generic types of support platforms are discussed, and their conceptual designs are given. Attention is given to the economics of such systems, emphasizing the busbar energy cost measures. Onshore energy costs are developed in terms of controlling environmental parameters, distance from shore and equipment type.

  10. A System for Retrospective Conversion.

    Science.gov (United States)

    Epstein, Hank

    1984-01-01

    The Apple-based MITINET system uses several forms of technology (Library of Congress MARC file in microfiche, microcomputers, COM vendor) to produce library database and COM catalog. Cost for MITINET software is based on number of branches or buildings performing conversion, and varies from $250 to $85 per building or branch. (EJS)

  11. HYDROKINETIC ENERGY CONVERSION SYSTEMS: PROSPECTS ...

    African Journals Online (AJOL)

    eobe

    Hydrokinetic energy conversion systems utilize the kinetic energy of flowing water bodies with little or no head to generate other useable forms of energy. In the last few years various research and development efforts have been made to bring out this technology from the proof of concept stage and to demonstrate its ...

  12. Photoelectrochemical based direct conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kocha, S.; Arent, D.; Peterson, M. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-09-01

    The goal of this research is to develop a stable, cost effective, photoelectrochemical based system that will split water upon illumination, producing hydrogen and oxygen directly, using sunlight as the only energy input. This type of direct conversion system combines a photovoltaic material and an electrolyzer into a single monolithic device. We report on our studies of two multifunction multiphoton photoelectrochemical devices, one based on the ternary semiconductor gallium indium phosphide, (GaInP{sub 2}), and the other one based on amorphous silicon carbide. We also report on our studies of the solid state surface treatment of GaInP{sub 2} as well as our continuing effort to develop synthetic techniques for the attachment of transition metal complexes to the surface of semiconductor electrodes. All our surface studies are directed at controlling the interface energetics and forming stable catalytic surfaces.

  13. Ocean energy conversion systems annual research report

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    Alternative power cycle concepts to the closed-cycle Rankine are evaluated and those that show potential for delivering power in a cost-effective and environmentally acceptable fashion are explored. Concepts are classified according to the ocean energy resource: thermal, waves, currents, and salinity gradient. Research projects have been funded and reported in each of these areas. The lift of seawater entrained in a vertical steam flow can provide potential energy for a conventional hydraulic turbine conversion system. Quantification of the process and assessment of potential costs must be completed to support concept evaluation. Exploratory development is being completed in thermoelectricity and 2-phase nozzles for other thermal concepts. Wave energy concepts are being evaluated by analysis and model testing with present emphasis on pneumatic turbines and wave focussing. Likewise, several conversion approaches to ocean current energy are being evaluated. The use of salinity resources requires further research in membranes or the development of membraneless processes. Using the thermal resource in a Claude cycle process as a power converter is promising, and a program of R and D and subsystem development has been initiated to provide confirmation of the preliminary conclusion.

  14. Wind Energy Conversion Systems Technology and Trends

    CERN Document Server

    2012-01-01

    Wind Energy Conversion System covers the technological progress of wind energy conversion systems, along with potential future trends. It includes recently developed wind energy conversion systems such as multi-converter operation of variable-speed wind generators, lightning protection schemes, voltage flicker mitigation and prediction schemes for advanced control of wind generators. Modeling and control strategies of variable speed wind generators are discussed, together with the frequency converter topologies suitable for grid integration. Wind Energy Conversion System also describes offshore farm technologies including multi-terminal topology and space-based wind observation schemes, as well as both AC and DC based wind farm topologies. The stability and reliability of wind farms are discussed, and grid integration issues are examined in the context of the most recent industry guidelines. Wind power smoothing, one of the big challenges for transmission system operators, is a particular focus. Fault ride th...

  15. NASA presentation. [wind energy conversion systems planning

    Science.gov (United States)

    Thomas, R. L.

    1973-01-01

    The development of a wind energy system is outlined that supplies reliable energy at a cost competitive with other energy systems. A government directed industry program with strong university support is recommended that includes meteorological studies to estimate wind energy potentials and determines favorable regions and sites for wind power installations. Key phases of the overall program are wind energy conversion systems, meteorological wind studies, energy storage systems, and environmental impact studies. Performance testing with a prototype wind energy conversion and storage system is projected for Fiscal 1977.

  16. A System for Electromagnetic Field Conversion

    DEFF Research Database (Denmark)

    2003-01-01

    A system is provided for conversion of a first electromagnetic field into a desired second electromagnetic field, for example for coupling modes between waveguides or into microstructured waveguides. The system comprises a complex spatial electromagnetic field converter that is positioned...... for reception of at least a part of the first electromagnetic field and that is adapted for conversion of the received field into the desired electromagnetic field, and wherein at least one of the first and second fields matches a mode of a microstructured waveguide. It is an important advantage of the present...

  17. Synchronous generator wind energy conversion control system

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)

    1996-12-31

    This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.

  18. Hydrokinetic Energy Conversion Systems: Prospects and ...

    African Journals Online (AJOL)

    Hydrokinetic energy conversion systems utilize the kinetic energy of flowing water bodies with little or no head to generate other useable forms of energy. In the last few years various research and development efforts have been made to bring out this technology from the proof of concept stage and to demonstrate its ...

  19. Systems and methods for wave energy conversion

    Science.gov (United States)

    MacDonald, Daniel G.; Cantara, Justin; Nathan, Craig; Lopes, Amy M.; Green, Brandon E.

    2017-02-28

    Systems for wave energy conversion that have components that can survive the harsh marine environment and that can be attached to fixed structures, such as a pier, and having the ability to naturally adjust for tidal height and methods for their use are presented.

  20. System Performance Projections for TPV Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    PF Baldasaro; MW Dashiell; JE Oppenlander; JL Vell; P Fourspring; K Rahner; LR Danielson; S Burger; E Brown

    2004-06-09

    TPV technology has advanced rapidly in the last five years, with diode conversion efficiency approaching >30%, and filter efficiency of {approx}80%. These achievements have enabled repeatable testing of 20% efficient small systems, demonstrating the potential of TPV energy conversion. Near term technology gains support a 25% efficient technology demonstration in the two year timeframe. However, testing of full size systems, which includes efficiency degradation mechanisms, such as: nonuniform diode illumination, diode and filter variability, temperature non-uniformities, conduction/convection losses, and lifetime reliability processes needs to be performed. A preliminary analysis of these differential effects has been completed, and indicates a near term integrated system efficiency of {approx}15% is possible using current technology, with long term growth to 18-20%. This report addresses the system performance issues.

  1. Optical Energy Transfer and Conversion System

    Science.gov (United States)

    Stone, William C. (Inventor); Hogan, Bartholomew P. (Inventor)

    2015-01-01

    An optical power transfer system comprising a fiber spooler, a fiber optic rotary joint mechanically connected to the fiber spooler, and an electrical power extraction subsystem connected to the fiber optic rotary joint with an optical waveguide. Optical energy is generated at and transferred from a base station through fiber wrapped around the spooler, through the rotary joint, and ultimately to the power extraction system at a remote mobility platform for conversion to another form of energy.

  2. Systems Requirement Document for the MSRE U-233 Conversion System

    Energy Technology Data Exchange (ETDEWEB)

    Aigner, R.D.

    2001-01-11

    The fissile material reclamation activities for the MSRE remediation project include the removal and recovery of uranium from the off-gas system, from the stored fuel salt, and finally, from the uranium-laden charcoal in the Auxiliary Charcoal Bed (ACB). Each of these operations produces an uranium/fluoride compound that is not suitable for long-term storage. The uranium-fluoride compounds can be stored for a limited period of time in pressure vessels. The interim-storage vessels are designed to handle the internal pressure buildup from gases formed by radiolysis of the uranium-fluoride compounds. The conversion process will take the pressurized vessels from interim storage and process the materials in a hot cell located at Building 4501. The gas in the vessels will be vented through chemical traps and then the traps will be processed to convert the various uranium-fluoride compounds to a stable uranium oxide form. This will be done one trap at a time. The chemical form of uranium being extracted from the off-gas system and from fuel salt fluorination process is uranium hexafluoride UF{sub 6}. During the operations at MSRE, the UF{sub 6} is chemisorbed onto sodium fluoride (NaF) traps where it forms the complex, 2NaF{center_dot}UF{sub 6}. The conversion process that will be installed in the Building 4501 Hot Cell D will recover the UF{sub 6} from the NaF traps by decomposition of the binary complex at elevated temperatures (>300 C). After the uranium is extracted from the NaF traps, it is collected in the conversion process reaction vessel. The reaction vessel is then hydrolized and heated through several step operations up to 900 C in order to convert the material to a stable uranium oxide. The ACB at MSRE contains uranium-laden charcoal with unstable C{sub x}F compounds. After extraction at MSRE, this material will be delivered to Building 4501 Hot Cell D for processing to a stable oxide. The charcoal conversion process is still under development, with mockup and

  3. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Neil Todreas; Pavel Hejzlar

    2008-06-30

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  4. Systems Engineering Model for ART Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Cruz, Carmen Margarita [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rochau, Gary E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, Mollye C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-02-01

    The near-term objective of the EC team is to establish an operating, commercially scalable Recompression Closed Brayton Cycle (RCBC) to be constructed for the NE - STEP demonstration system (demo) with the lowest risk possible. A systems engineering approach is recommended to ensure adequate requirements gathering, documentation, and mode ling that supports technology development relevant to advanced reactors while supporting crosscut interests in potential applications. A holistic systems engineering model was designed for the ART Energy Conversion program by leveraging Concurrent Engineering, Balance Model, Simplified V Model, and Project Management principles. The resulting model supports the identification and validation of lifecycle Brayton systems requirements, and allows designers to detail system-specific components relevant to the current stage in the lifecycle, while maintaining a holistic view of all system elements.

  5. Energy technology sources, systems and frontier conversion

    CERN Document Server

    Ohta, Tokio

    1994-01-01

    This book provides a concise and technical overview of energy technology: the sources of energy, energy systems and frontier conversion. As well as serving as a basic reference book for professional scientists and students of energy, it is intended for scientists and policy makers in other disciplines (including practising engineers, biologists, physicists, economists and managers in energy related industries) who need an up-to-date and authoritative guide to the field of energy technology.Energy systems and their elemental technologies are introduced and evaluated from the view point

  6. Education System Benefits of U.S. Metric Conversion.

    Science.gov (United States)

    Phelps, Richard P.

    1996-01-01

    U.S. metric conversion efforts are reviewed as they have affected education. Education system benefits and costs are estimated for three possible system conversion plans. The soft-conversion-to-metric plan, which drops all inch-pound instruction, appears to provide the largest net benefits. The primary benefit is in class time saved. (SLD)

  7. Mount Sinai Hospital's approach to Ontario's Health System Funding Reform.

    Science.gov (United States)

    Chalk, Tyler; Lau, Davina; Morgan, Matthew; Dietrich, Sandra; Beduz, Mary Agnes; Bell, Chaim M

    2014-01-01

    In April 2012, the Ontario government introduced Health System Funding Reform (HSFR), a transformational shift in how hospitals are funded. Mount Sinai Hospital recognized that moving from global funding to a "patient-based" model would have substantial operational and clinical implications. Adjusting to the new funding environment was set as a top corporate priority, serving as the strategic basis for re-examining and redesigning operations to further improve both quality and efficiency. Two years into HSFR, this article outlines Mount Sinai Hospital's approach and highlights key lessons learned. Copyright © 2014 Longwoods Publishing.

  8. ACCOUNTING SYSTEM OF THE MARKET OF UNIT INVESTMENT FUNDS

    Directory of Open Access Journals (Sweden)

    Olga A. Zhdanova

    2013-01-01

    Full Text Available Functions and interrelations of depositary, specialized depositary and registrar operating in the market of unit investment funds are presented and studied in the article. The conclusion is drawn on possibility of introduction of concept of accounting system in the market of unit investment funds.

  9. Technology assessment of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Meier, B. W.; Merson, T. J.

    1980-09-01

    Environmental data for wind energy conversion systems (WECSs) have been generated in support of the Technology Assessment of Solar Energy (TASE) program. Two candidates have been chosen to characterize the WECS that might be deployed if this technology makes a significant contribution to the national energy requirements. One WECS is a large machine of 1.5-MW-rated capacity that can be used by utilities. The other WECS is a small machine that is characteristic of units that might be used to meet residential or small business energy requirements. Energy storage systems are discussed for each machine to address the intermittent nature of wind power. Many types of WECSs are being studied and a brief review of the technology is included to give background for choosing horizontal axis designs for this study. Cost estimates have been made for both large and small systems as required for input to the Strategic Environmental Assessment Simulation (SEAS) computer program. Material requirements, based on current generation WECSs, are discussed and a general discussion of environmental impacts associated with WECS deployment is presented.

  10. Drinking Water State Revolving Fund National Information Management System Reports

    Science.gov (United States)

    The Drinking Water State Revolving Fund (DWSRF) National Information Management System collects information that provide a record of progress and accountability for the program at both the State and National level.

  11. Thermal Noise Can Facilitate Energy Conversion by Ratchet System?

    OpenAIRE

    Takagi, Fumiko; Hondou, Tsuyoshi

    1999-01-01

    Molecular motors in biological systems are expected to use ambient fluctuation. In a recent Letter [Phys. Rev. Lett. {\\bf 80}, 5251 (1998)], it was showed that the following question was unsolved, ``Can thermal noise facilitate energy conversion by ratchet system?'' We consider it using stochastic energetics, and show that there exist systems where thermal noise helps the energy conversion.

  12. Photoelectrochemical solar conversion systems molecular and electronic aspects

    CERN Document Server

    Munoz, Andres G

    2012-01-01

    Providing new insights into the molecular and electronic processes involved in the conversion of sunlight into chemical products, Photoelectrochemical Solar Conversion Systems: Molecular and Electronic Aspects begins with an historical overview and a survey of recent developments in the electrochemistry of semiconductors and spectroscopic techniques. It then provides a comprehensive introduction to the science of conversion cells, reviews current issues and potential directions, and covers a wide range of materials from organic to inorganic cells.Employing a tutorial organization with balanced

  13. Study of Systemic Risk Involved in Mutual Funds

    Science.gov (United States)

    Dash, Kishore C.; Dash, Monika

    Systemic risk, may be defined as the risk that contaminates to the whole system, consisting of many interacting agents that fail one after another. These agents, in an economic context, could be firms, banks, funds, or other financial institutions. Systemic risk is a macroscopic property of a system which emerges due to the nonlinear interaction of agents on a microscopic level. A stock market itself is a system in which there are many sub-systems, like Dowjones, Nifty, Sensex, Nasdaq, Nikkei and other market indices in global perspective. In Indian market, subsystems may be like Sensex, Nifty, BSE200, Bankex, smallcap index, midcap index, S&P CNX 500 and many others. Similarly there are many mutual funds, which have their own portfolio of different stocks, bonds etc. We have attempted to study the systemic risk involved in a fund as a macroscopic object with regard to its microscopic components as different stocks in its portfolio. It is observed that fund managers do manage to reduce the systemic risk just like we take precautions to control the spread of an epidemic.

  14. The school funding system and its discriminatory impact on ...

    African Journals Online (AJOL)

    South Africa in reality harbours two separate education systems in its public school domain: one consisting of the former white schools, which is adequately resourced, and the other constituting the township and rural schools entrenched in abject poverty. The current school funding system perpetuates this state of inequality ...

  15. Renewable energy systems advanced conversion technologies and applications

    CERN Document Server

    Luo, Fang Lin

    2012-01-01

    Energy conversion techniques are key in power electronics and even more so in renewable energy source systems, which require a large number of converters. Renewable Energy Systems: Advanced Conversion Technologies and Applications describes advanced conversion technologies and provides design examples of converters and inverters for renewable energy systems-including wind turbine and solar panel energy systems. Learn Cutting-Edge Techniques for Converters and Inverters Setting the scene, the book begins with a review of the basics of astronomy and Earth physics. It then systematically introduc

  16. Conversion of serial holdings into automated library system in ...

    African Journals Online (AJOL)

    Records conversion is a must in a newly automated library system. As a result of the recent development in automation at the University of Ilorin library, almost all the monograph collection have been converted to readable format, while the conversion of the serials records remain dormant. The article discusses the attempt ...

  17. Closed Brayton cycle power conversion systems for nuclear reactors :

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Steven A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vernon, Milton E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sanchez, Travis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2006-04-01

    This report describes the results of a Sandia National Laboratories internally funded research program to study the coupling of nuclear reactors to gas dynamic Brayton power conversion systems. The research focused on developing integrated dynamic system models, fabricating a 10-30 kWe closed loop Brayton cycle, and validating these models by operating the Brayton test-loop. The work tasks were performed in three major areas. First, the system equations and dynamic models for reactors and Closed Brayton Cycle (CBC) systems were developed and implemented in SIMULINKTM. Within this effort, both steady state and dynamic system models for all the components (turbines, compressors, reactors, ducting, alternators, heat exchangers, and space based radiators) were developed and assembled into complete systems for gas cooled reactors, liquid metal reactors, and electrically heated simulators. Various control modules that use proportional-integral-differential (PID) feedback loops for the reactor and the power-conversion shaft speed were also developed and implemented. The simulation code is called RPCSIM (Reactor Power and Control Simulator). In the second task an open cycle commercially available Capstone C30 micro-turbine power generator was modified to provide a small inexpensive closed Brayton cycle test loop called the Sandia Brayton test-Loop (SBL-30). The Capstone gas-turbine unit housing was modified to permit the attachment of an electrical heater and a water cooled chiller to form a closed loop. The Capstone turbine, compressor, and alternator were used without modification. The Capstone systems nominal operating point is 1150 K turbine inlet temperature at 96,000 rpm. The annular recuperator and portions of the Capstone control system (inverter) and starter system also were reused. The rotational speed of the turbo-machinery is controlled by adjusting the alternator load by using the electrical grid as the load bank. The SBL-30 test loop was operated at

  18. Research funding systems in Australia, New Zealand and the UK

    DEFF Research Database (Denmark)

    Lewis, Jenny; Ross, S

    2011-01-01

    . This article reports on a study involving interviews with 274 academics at universities in Australia (Melbourne), New Zealand (Auckland) and the UK (Birmingham). Perceptions of the three research funding systems demonstrated significant differences across universities, and some interesting gender and seniority...

  19. tate management of the mandatory funded pension system in Ukraine

    Directory of Open Access Journals (Sweden)

    V. M. Vereshchak

    2017-03-01

    According to the opinion of the author, the mechanism of creation and use of pension savings is an ongoing management decision. Its activity is controlled not only by the state but also by other actors and participants of the funded system.

  20. PERFORMANCE EVALUATION OF PENSION FUNDS WITH FUZZY EXPERT SYSTEM

    Directory of Open Access Journals (Sweden)

    SERDAR KORUKOĞLU

    2013-06-01

    Full Text Available Financial rating and ranking firms often use linguistic instead of numerical values. When input data are mostly qualitative and are based on subjective knowledge of experts, the Fuzzy Set Theory provides a solid mathematical model to represent and handle these data. The aim of this study is developing a fuzzy expert model to evaluate the performance of the pension funds by using their risk and return values. The method is used for evaluating the performance of the randomly selected of twenty seven Turkish pension funds. The obtained results proved that the fuzzy expert system is appropriate and consistent for performance evaluation.

  1. Light distribution system comprising spectral conversion means

    DEFF Research Database (Denmark)

    2012-01-01

    System (200, 300) for the distribution of white light, having a supply side (201, 301, 401) and a delivery side (202, 302, 402), the system being configured for guiding light with a multitude of visible wavelengths in a propagation direction P from the supply side to the distribution side, the sy...... of providing a light distribution system and a method of correcting the spectral transmission characteristics of a light distribution system are disclosed....

  2. Guest Editorial Advanced Distributed Control of Energy Conversion Devices and Systems

    DEFF Research Database (Denmark)

    Davoudi, Ali; Guerrero, Josep M.; Lewis, Frank

    2014-01-01

    The papers in this special issue on advanced distributed control of energy conversion devices and systems are loosely grouped into three categories: 1) ac energy conversion systems; 2) dc energy conversion systems; and 3) optimization and standards....

  3. Improvements of the One-to-Many Eigenvoice Conversion System

    Science.gov (United States)

    Ohtani, Yamato; Toda, Tomoki; Saruwatari, Hiroshi; Shikano, Kiyohiro

    We have developed a one-to-many eigenvoice conversion (EVC) system that allows us to convert a single source speaker's voice into an arbitrary target speaker's voice using an eigenvoice Gaussian mixture model (EV-GMM). This system is capable of effectively building a conversion model for an arbitrary target speaker by adapting the EV-GMM using only a small amount of speech data uttered by the target speaker in a text-independent manner. However, the conversion performance is still insufficient for the following reasons: 1) the excitation signal is not precisely modeled; 2) the oversmoothing of the converted spectrum causes muffled sounds in converted speech; and 3) the conversion model is affected by redundant acoustic variations among a lot of pre-stored target speakers used for building the EV-GMM. In order to address these problems, we apply the following promising techniques to one-to-many EVC: 1) mixed excitation; 2) a conversion algorithm considering global variance; and 3) adaptive training of the EV-GMM. The experimental results demonstrate that the conversion performance of one-to-many EVC is significantly improved by integrating all of these techniques into the one-to-many EVC system.

  4. Care and Conversing in Dialogical Systems

    DEFF Research Database (Denmark)

    Steffensen, Sune Vork

    2012-01-01

    This article promotes a point of view on human interaction in terms of dialogical systems. The approach draws on recent, so-called third wave, developments in cognitive science. After an introduction to three waves in cognitive science, and their counterparts in linguistics, the article is placed...... in a tradition that is ecological, embodied and distributed. Its specific take on human interaction pursues these perspectives by claiming that language can neither be reduced to social rules in the micro-sociological domain, nor to biological properties of the individual being. As an alternative to these two...... positions, a theory of dialogical systems is developed, on the basis of current thinking within the enactive program (e.g. De Jaegher and Di Paolo, 2007), the distributed language movement (e.g. Cowley, 2011b), and values-realizing theory (e.g. Hodges, 2009). Dialogical systems are systems of co...

  5. COMPARATIVE STUDY OF OWN FUNDS IN THE BANKING SYSTEM

    Directory of Open Access Journals (Sweden)

    Tesu Ramona

    2012-12-01

    Full Text Available The present article has as a reserch field theoretical, methodological and practical aspects of the own funds, taking into account the line-up attempts of the romanian banking system to the requirements of the European Union, materialised in the Basel Agreement. The objectives of the research theme, presented in this paper, are mainly oriented towards own funds. We also proposed the following secondary objectives: presenting the concept approaches concerning own funds, emphasysing the tipology of own funds and pointing out their purpose in the banking activity; presenting and analyse the evolution of the own funds in Romania, for a period of 8 years (2004-2011. Even though the actual stage of the research in this field is advanced, in the romanian and foreign literature which dedicate a lot of theoretical and empiric studies concerning own funds. In our study we will use a theoretical and a practical research. The theoretical research describes the laws, reglementations and rules of application in the banking field in our country. In the practical part we will use as a research method the quality-comparative analyse by presenting details regarding bank back-ups. Despite the global financial crisis, the Romanian banking system can be considered as stable as a whole, with levels of capitalization, solvency and liquidity in accordance with consistent with prudential requirements. Tier 1, defined as the core of their sources of credit institutions through the permanent criteria, payment flexibility and capacity to absorb losses continued to overwhelmingly support a total equity. Appropriate quality of own funds is on their structure. The most important component frame our capital plus capital frame attached. The second component in terms is still represented by legal reserves. An important challenge for banks was to maintain a level of own funds accordance, in the conditions witch they were eroded by the current period losses. Tier 2 support rate of

  6. Heat Rejection Concepts for Brayton Power Conversion Systems

    Science.gov (United States)

    Siamidis, John; Mason, Lee; Beach, Duane; Yuko, James

    2005-01-01

    This paper describes potential heat rejection design concepts for closed Brayton cycle (CBC) power conversion systems. Brayton conversion systems are currently under study by NASA for Nuclear Electric Propulsion (NEP) applications. The Heat Rejection Subsystem (HRS) must dissipate waste heat generated by the power conversion system due to inefficiencies in the thermal-to-electric conversion process. Space Brayton conversion system designs tend to optimize at efficiencies of about 20 to 25 percent with radiator temperatures in the 400 to 600 K range. A notional HRS was developed for a 100 kWe-class Brayton power system that uses a pumped sodium-potassium (NaK) heat transport loop coupled to a water heat pipe radiator. The radiator panels employ a sandwich construction consisting of regularly-spaced circular heat pipes contained within two composite facesheets. Heat transfer from the NaK fluid to the heat pipes is accomplished by inserting the evaporator sections into the NaK duct channel. The paper evaluates various design parameters including heat pipe diameter, heat pipe spacing, and facesheet thickness. Parameters were varied to compare design options on the basis of NaK pump pressure rise and required power, heat pipe unit power and radial flux, radiator panel areal mass, and overall HRS mass.

  7. Field Support System (FS-AID) and Working Capital Fund Tracking System (WCF-TS)

    Data.gov (United States)

    US Agency for International Development — The Field Support System (FS-AID) and Working Capital Fund Tracking System (WCF-TS) are two modules of a single data management system that share common tables and...

  8. Gate controlled high efficiency ballistic energy conversion system

    NARCIS (Netherlands)

    Xie, Yanbo; Bos, Diederik; de Boer, Hans L.; van den Berg, Albert; Eijkel, Jan C.T.; Zengerle, R.

    2013-01-01

    Last year we demonstrated the microjet ballistic energy conversion system[1]. Here we show that the efficiency of such a system can be further improved by gate control. With gate control the electrical current generation is enhanced a hundred times with respect to the current generated from the zeta

  9. A Prototype Greek Text to Greek Sign Language Conversion System

    Science.gov (United States)

    Kouremenos, Dimitris; Fotinea, Stavroula-Evita; Efthimiou, Eleni; Ntalianis, Klimis

    2010-01-01

    In this article, a prototype Greek text to Greek Sign Language (GSL) conversion system is presented. The system is integrated into an educational platform that addresses the needs of teaching GSL grammar and was developed within the SYNENNOESE project (Efthimiou "et al." 2004a. Developing an e-learning platform for the Greek sign…

  10. Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels: Conversion Pathway: Biological Conversion of Sugars to Hydrocarbons The 2017 Design Case

    Energy Technology Data Exchange (ETDEWEB)

    Kevin Kenney; Kara G. Cafferty; Jacob J. Jacobson; Ian J Bonner; Garold L. Gresham; William A. Smith; David N. Thompson; Vicki S. Thompson; Jaya Shankar Tumuluru; Neal Yancey

    2013-09-01

    The U.S. Department of Energy promotes the production of a range of liquid fuels and fuel blendstocks from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass collection, conversion, and sustainability. As part of its involvement in this program, the Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL conducted a campaign to quantify the economics and sustainability of moving biomass from standing in the field or stand to the throat of the biomass conversion process. The goal of this program was to establish the current costs based on conventional equipment and processes, design improvements to the current system, and to mark annual improvements based on higher efficiencies or better designs. The 2012 programmatic target was to demonstrate a delivered biomass logistics cost of $35/dry ton. This goal was successfully achieved in 2012 by implementing field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model. Looking forward to 2017, the programmatic target is to supply biomass to the conversion facilities at a total cost of $80/dry ton and on specification with in-feed requirements. The goal of the 2017 Design Case is to enable expansion of biofuels production beyond highly productive resource areas by breaking the reliance of cost-competitive biofuel production on a single, abundant, low-cost feedstock. If this goal is not achieved, biofuel plants are destined to be small and/or clustered in select regions of the country that have a lock on low-cost feedstock. To put the 2017 cost target into perspective of past accomplishments of the cellulosic ethanol pathway, the $80 target encompasses total delivered feedstock cost, including both grower payment and logistics costs, while meeting all

  11. Tandem filters using frequency selective surfaces for enhanced conversion efficiency in a thermophotovoltaic energy conversion system

    Science.gov (United States)

    Dziendziel, Randolph J [Middle Grove, NY; Baldasaro, Paul F [Clifton Park, NY; DePoy, David M [Clifton Park, NY

    2010-09-07

    This invention relates to the field of thermophotovoltaic (TPV) direct energy conversion. In particular, TPV systems use filters to minimize parasitic absorption of below bandgap energy. This invention constitutes a novel combination of front surface filters to increase TPV conversion efficiency by reflecting useless below bandgap energy while transmitting a very high percentage of the useful above bandgap energy. In particular, a frequency selective surface is used in combination with an interference filter. The frequency selective surface provides high transmission of above bandgap energy and high reflection of long wavelength below bandgap energy. The interference filter maintains high transmission of above bandgap energy and provides high reflection of short wavelength below bandgap energy and a sharp transition from high transmission to high reflection.

  12. 28 CFR 23.40 - Monitoring and auditing of grants for the funding of intelligence systems.

    Science.gov (United States)

    2010-07-01

    ... funding of intelligence systems. 23.40 Section 23.40 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL INTELLIGENCE SYSTEMS OPERATING POLICIES § 23.40 Monitoring and auditing of grants for the funding of intelligence systems. (a) Awards for the funding of intelligence systems will receive specialized...

  13. Recent Progress on Integrated Energy Conversion and Storage Systems.

    Science.gov (United States)

    Luo, Bin; Ye, Delai; Wang, Lianzhou

    2017-09-01

    Over the last few decades, there has been increasing interest in the design and construction of integrated energy conversion and storage systems (IECSSs) that can simultaneously capture and store various forms of energies from nature. A large number of IECSSs have been developed with different combination of energy conversion technologies such as solar cells, mechanical generators and thermoelectric generators and energy storage devices such as rechargeable batteries and supercapacitors. This review summarizes the recent advancements to date of IECSSs based on different energy sources including solar, mechanical, thermal as well as multiple types of energies, with a special focus on the system configuration and working mechanism. With the rapid development of new energy conversion and storage technologies, innovative high performance IECSSs are of high expectation to be realised for diverse practical applications in the near future.

  14. Design of video interface conversion system based on FPGA

    Science.gov (United States)

    Zhao, Heng; Wang, Xiang-jun

    2014-11-01

    This paper presents a FPGA based video interface conversion system that enables the inter-conversion between digital and analog video. Cyclone IV series EP4CE22F17C chip from Altera Corporation is used as the main video processing chip, and single-chip is used as the information interaction control unit between FPGA and PC. The system is able to encode/decode messages from the PC. Technologies including video decoding/encoding circuits, bus communication protocol, data stream de-interleaving and de-interlacing, color space conversion and the Camera Link timing generator module of FPGA are introduced. The system converts Composite Video Broadcast Signal (CVBS) from the CCD camera into Low Voltage Differential Signaling (LVDS), which will be collected by the video processing unit with Camera Link interface. The processed video signals will then be inputted to system output board and displayed on the monitor.The current experiment shows that it can achieve high-quality video conversion with minimum board size.

  15. National health management information system: issues of funding and support.

    Science.gov (United States)

    Akinde, A D; Soriyan, H A; Makanjuola, R O

    1997-02-01

    Information Technology has made a substantial inroad into Nigerian society, particularly since the late 1980s. It is, however, already being applied in the health sector. The Obafemi Awolowo University Teaching Hospitals Complex (OAUTHC), lle-lfe, Nigeria has adopted a systematic approach to the development of a Health Information System (HIS) for a typical specialist hospital. A review of the existing HIS in OAUIHC is presented, highlighting its attributes, problems, and limitations. In addition, the options of funding HIS on a national scale are identified and discussed. Finally, strategies to ensure ongoing support of a national HIS are presented.

  16. Inertial confinement fusion reaction chamber and power conversion system study

    Energy Technology Data Exchange (ETDEWEB)

    Maya, I.; Schultz, K.R.; Battaglia, J.M.; Buksa, J.J.; Creedson, R.L.; Erlandson, O.D.; Levine, H.E.; Roelant, D.F.; Sanchez, H.W.; Schrader, S.A.

    1984-09-01

    GA Technologies has developed a conceptual ICF reactor system based on the Cascade rotating-bed reaction chamber concept. Unique features of the system design include the use of low activation SiC in a reaction chamber constructed of box-shaped tiles held together in compression by prestressing tendons to the vacuum chamber. Circulating Li/sub 2/O granules serve as the tritium breeding and energy transport material, cascading down the sides of the reaction chamber to the power conversion system. The total tritium inventory of the system is 6 kg; tritium recovery is accomplished directly from the granules via the vacuum system. A system for centrifugal throw transport of the hot Li/sub 2/O granules from the reaction chamber to the power conversion system has been developed. A number of issues were evaluated during the course of this study. These include the response of first-layer granules to the intense microexplosion surface heat flux, cost effective fabrication of Li/sub 2/O granules, tritium inventory and recovery issues, the thermodynamics of solids-flow options, vacuum versus helium-medium heat transfer, and the tradeoffs of capital cost versus efficiency for alternate heat exchange and power conversion system option. The resultant design options appear to be economically competitive, safe, and environmentally attractive.

  17. Surface plasmon polaritons mode conversion via a coupled plasmonic system

    Science.gov (United States)

    Yang, Fan; Tian, Hao

    2016-05-01

    A coupled plasmonic system for effective mode conversion between single interface surface plasmon polaritons (SPP) in a metal-dielectric waveguide and gap SPP in a metal-dielectric-metal waveguide is proposed. With the modal analysis, it is shown that the interference of the two plasmonic modes in a metal-dielectric-metal-dielectric coupled structure plays the key role in the mode conversion. With typical parameters, the conversion efficiency is as high as 61% (equivalent to 87% of the output total energy flow) at 1μm wavelength, and 1 dB bandwidth is as broad as 300 nm. The proposed structure can be used to implement an SPP mode convertor, router and beam splitter, which enables the interconnection between two important waveguides in plasmonics. The method presented here is fully-analytical, and is tested against fully-vectorial numerical results.

  18. Thermodynamic limits to the conversion of blackbody radiation by quantum systems. [with application to solar energy conversion devices

    Science.gov (United States)

    Buoncristiani, A. M.; Smith, B. T.; Byvik, C. E.

    1982-01-01

    Using general thermodynamic arguments, we analyze the conversion of the energy contained in the radiation from a blackbody to useful work by a quantum system. We show that the energy available for conversion is bounded above by the change in free energy in the incident and reradiated fields and that this free energy change depends upon the temperature of the receiving device. Universal efficiency curves giving the ultimate thermodynamic conversion efficiency of the quantum system are presented in terms of the blackbody temperature and the temperature and threshold energy of the quantum system. Application of these results is made to a variety of systems including biological photosynthetic, photovoltaic, and photoelectrochemical systems.

  19. Physical Limits of Solar Energy Conversion in the Earth System.

    Science.gov (United States)

    Kleidon, Axel; Miller, Lee; Gans, Fabian

    2016-01-01

    Solar energy provides by far the greatest potential for energy generation among all forms of renewable energy. Yet, just as for any form of energy conversion, it is subject to physical limits. Here we review the physical limits that determine how much energy can potentially be generated out of sunlight using a combination of thermodynamics and observed climatic variables. We first explain how the first and second law of thermodynamics constrain energy conversions and thereby the generation of renewable energy, and how this applies to the conversions of solar radiation within the Earth system. These limits are applied to the conversion of direct and diffuse solar radiation - which relates to concentrated solar power (CSP) and photovoltaic (PV) technologies as well as biomass production or any other photochemical conversion - as well as solar radiative heating, which generates atmospheric motion and thus relates to wind power technologies. When these conversion limits are applied to observed data sets of solar radiation at the land surface, it is estimated that direct concentrated solar power has a potential on land of up to 11.6 PW (1 PW=10(15) W), whereas photovoltaic power has a potential of up to 16.3 PW. Both biomass and wind power operate at much lower efficiencies, so their potentials of about 0.3 and 0.1 PW are much lower. These estimates are considerably lower than the incoming flux of solar radiation of 175 PW. When compared to a 2012 primary energy demand of 17 TW, the most direct uses of solar radiation, e.g., by CSP or PV, have thus by far the greatest potential to yield renewable energy requiring the least space to satisfy the human energy demand. Further conversions into solar-based fuels would be reduced by further losses which would lower these potentials. The substantially greater potential of solar-based renewable energy compared to other forms of renewable energy simply reflects much fewer and lower unavoidable conversion losses when solar

  20. The Sardinia Radio Telescope conversion, distribution, and receiver control system

    Science.gov (United States)

    Monari, J.; Orfei, A.; Scalambra, A.; Mariotti, S.; Poloni, M.; Fiocchi, F.; Cattani, A.; Maccaferri, A.; Perini, F.; Boschi, M.

    The recent upgrade of the 32-m radio telescope located in Medicina (Bologna - Italy) has allowed us to gain a lot of know-how about ''frequency agility'' management. In this parabolic dish antenna the receiver change is now completely performed only using software controls and avoiding, in this way, human intervention. The acquired experience on this topic has been used to define the framework for the conversion/distribution system design for the SRT (Sardinia Radio Telescope), the new ''64-meter class'' Italian radio telescope. The suitably designed architectures for Local Oscillators (LOs), Intermediate Frequencies (IFs), Ground Unit (GU), Reference (REF) distribution systems and control system will be described in this paper.

  1. Spectral light management for solar energy conversion systems

    Directory of Open Access Journals (Sweden)

    Stanley Cameron

    2016-06-01

    Full Text Available Due to the inherent broadband nature of the solar radiation, combined with the narrow spectral sensitivity range of direct solar to electricity devices, there is a massive opportunity to manipulate the solar spectrum to increase the functionality and efficiency of solar energy conversion devices. Spectral splitting or manipulation facilitates the efficient combination of both high-temperature solar thermal systems, which can absorb over the entire solar spectrum to create heat, and photovoltaic cells, which only convert a range of wavelengths to electricity. It has only recently been possible, with the development of nanofabrication techniques, to integrate micro- and nano-photonic structures as spectrum splitters/manipulators into solar energy conversion devices. In this paper, we summarize the recent developments in beam splitting techniques, and highlight some relevant applications including combined PV-thermal collectors and efficient algae production, and suggest paths for future development in this field.

  2. ARGICULTURAL LAND PROTECTION FUND AND FOREST FUND AS ECOLOGICAL FUNDS

    OpenAIRE

    Bartosz Bartniczak

    2009-01-01

    Funds for environmental protection and water management, Agricultural Land Protection Fund and Forest Fund make up the Polish system of special fund in environment protection. The main aim of this article is to analyze the activity of two latest funds. The article tries to answer the question whether that funds could be considered as ecological funds. The author described incomes and outlays of that funds and showed which reform should be done in Polish special funds system.

  3. Standards for photovoltaic energy conversion systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schafft, H. A.

    1980-04-01

    This report provides the results of a search for existing domestic standards and related documents for possible application in the development of a standards base for photovoltaic energy conversion systems. The search resulted in locating about 150 test methods, recommended practices, standards, solar-thermal performance criteria, and other standards-related documents. They are listed by topic areas in the appendix. The listing was prepared to assist those involved in developing performance criteria for photovoltaic systems and in identifying methods to test system performance against these criteria. It is clear from the results of the search that few standards are directly applicable to terrestrial solar photovoltaic systems and that much standards development is required to support the commercialization of such systems.

  4. Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels Conversion Pathway: Fast Pyrolysis and Hydrotreating Bio-Oil Pathway "The 2017 Design Case"

    Energy Technology Data Exchange (ETDEWEB)

    Kevin L. Kenney; Kara G. Cafferty; Jacob J. Jacobson; Ian J. Bonner; Garold L. Gresham; J. Richard Hess; William A. Smith; David N. Thompson; Vicki S. Thompson; Jaya Shankar Tumuluru; Neal Yancey

    2014-01-01

    The U.S. Department of Energy promotes the production of liquid fuels from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass sustainable supply, logistics, conversion, and overall system sustainability. As part of its involvement in this program, Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL quantified and the economics and sustainability of moving biomass from the field or stand to the throat of the conversion process using conventional equipment and processes. All previous work to 2012 was designed to improve the efficiency and decrease costs under conventional supply systems. The 2012 programmatic target was to demonstrate a biomass logistics cost of $55/dry Ton for woody biomass delivered to fast pyrolysis conversion facility. The goal was achieved by applying field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model.

  5. Supercritical Carbon Dioxide Brayton Cycle Energy Conversion System

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jae Eun; Kim, S. O.; Seong, S. H.; Eoh, J. H.; Lee, T. H.; Choi, S. K.; Han, J. W.; Bae, S. W

    2007-12-15

    This report contains the description of the S-CO{sub 2} Brayton cycle coupled to KALIMER-600 as an alternative energy conversion system. For system development, a computer code was developed to calculate heat balance of 100% power operation condition. Based on the computer code, the S-CO{sub 2} Brayton cycle energy conversion system was constructed for the KALIMER-600. Using the developed turbomachinery models, the off-design characteristics and the sensitivities of the S-CO{sub 2} turbomachinery were investigated. For the development of PCHE models, a one-dimensional analysis computer code was developed to evaluate the performance of the PCHE. Possible control schemes for power control in the KALIMER-600 S-CO{sub 2} Brayton cycle were investigated by using the MARS code. Simple power reduction and recovery event was selected and analyzed for the transient calculation. For the evaluation of Na/CO{sub 2} boundary failure event, a computer was developed to simulate the complex thermodynamic behaviors coupled with the chemical reaction between liquid sodium and CO{sub 2} gas. The long term behavior of a Na/CO{sub 2} boundary failure event and its consequences which lead to a system pressure transient were evaluated.

  6. Design and Construction for Community Health Service Precision Fund Appropriation System Based on Performance Management.

    Science.gov (United States)

    Gao, Xing; He, Yao; Hu, Hongpu

    2017-01-01

    Allowing for the differences in economy development, informatization degree and characteristic of population served and so on among different community health service organizations, community health service precision fund appropriation system based on performance management is designed, which can provide support for the government to appropriate financial funds scientifically and rationally for primary care. The system has the characteristic of flexibility and practicability, in which there are five subsystems including data acquisition, parameter setting, fund appropriation, statistical analysis system and user management.

  7. Parallel photomask pattern data conversion and verification system

    Science.gov (United States)

    Kanai, Yasunori; Shimada, Toshiji; Sekigawa, Kazunari; Nishi, Makoto; Ishihara, Yasufumi; Mori, Jun-ichi; Akutagawa, Satoshi; Takahashi, Kazuhiko; Miyauchi, Touru

    1996-07-01

    This system is designed to convert and to verify different types of LSI layout design data and EB writer data, such as GDS-II, MEBES, and JEOL, with the help of its original internal format. The internal format data can be processed not only by a single workstation sequentially but also by network-linked workstations or a single workstation having two or more processing units concurrently. This parallel processing mechanism enables the system to reduce total processing time when handling large volume of data. The resultant internal format data produced by the conversion processes including logical operations, magnifications, and re-sizing operations can be immediately verified by built-in DRC program that is driven by a series of user commands, which consequently yields highly reliable output EB writer data. The built-in pattern viewer can graphically visualize any combination of the layout design data, the EB writer data, and the results of each conversion and verification in the same display window to provide users with an intuitive and easy method for verification. The features of the system and the parallel processing performance are described in this paper.

  8. Computer-Assisted English Learning System Based on Free Conversation by Topic

    Science.gov (United States)

    Choi, Sung-Kwon; Kwon, Oh-Woog; Kim, Young-Kil

    2017-01-01

    This paper aims to describe a computer-assisted English learning system using chatbots and dialogue systems, which allow free conversation outside the topic without limiting the learner's flow of conversation. The evaluation was conducted by 20 experimenters. The performance of the system based on a free conversation by topic was measured by the…

  9. Photoelectrochemical based direct conversion systems for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Kocha, S.; Peterson, M.; Arent, D. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-10-01

    Photon driven, direct conversion systems consist of a light absorber and a water splitting catalyst as a monolithic system; water is split directly upon illumination. This one-step process eliminates the need to generate electricity externally and subsequently feed it to an electrolyzer. These configurations require only the piping necessary for transport of hydrogen to an external storage system or gas pipeline. This work is focused on multiphoton photoelectrochemical devices for production of hydrogen directly using sunlight and water. Two types of multijunction cells, one consisting of a-Si triple junctions and the other GaInP{sub 2}/GaAs homojunctions, were studied for the photoelectrochemical decomposition of water into hydrogen and oxygen from an aqueous electrolyte solution. To catalyze the water decomposition process, the illuminated surface of the device was modified either by addition of platinum colloids or by coating with ruthenium dioxide. These colloids have been characterized by gel electrophoresis.

  10. Segregated tandem filter for enhanced conversion efficiency in a thermophotovoltaic energy conversion system

    Science.gov (United States)

    Brown, Edward J.; Baldasaro, Paul F.; Dziendziel, Randolph J.

    1997-01-01

    A filter system to transmit short wavelength radiation and reflect long wavelength radiation for a thermophotovoltaic energy conversion cell comprises an optically transparent substrate segregation layer with at least one coherent wavelength in optical thickness; a dielectric interference filter deposited on one side of the substrate segregation layer, the interference filter being disposed toward the source of radiation, the interference filter including a plurality of alternating layers of high and low optical index materials adapted to change from transmitting to reflecting at a nominal wavelength .lambda..sub.IF approximately equal to the bandgap wavelength .lambda..sub.g of the thermophotovoltaic cell, the interference filter being adapted to transmit incident radiation from about 0.5.lambda..sub.IF to .lambda..sub.IF and reflect from .lambda..sub.IF to about 2.lambda..sub.IF ; and a high mobility plasma filter deposited on the opposite side of the substrate segregation layer, the plasma filter being adapted to start to become reflecting at a wavelength of about 1.5.lambda..sub.IF.

  11. Designing Energy Conversion Systems for the Next Decade

    Directory of Open Access Journals (Sweden)

    Slobodan N. Vukosavić

    2012-12-01

    Full Text Available Sustainable growth in energy consumption requires transition to clean and green energy sources and energy systems. Environment friendly and renewable energy systems deal with electrical energy and rely on efficient electrical power converters. High power electronics is the key technology to deal with the next generation of electrical energy systems. The door to future breakthroughs in high power electronics is opened by major improvement in semiconductor power devices and their packaging technologies. New materials allow for much higher junction temperatures and higher operating voltages. Most importantly, advanced power semiconductor devices and novel converter topology open the possibility to increase the energy efficiency of power conversion and reduce the amount of heat. Although the waste heat created by high power converters can be put to use by adding on to heating systems, this option is not always available and the conversion losses are mostly wasted. At the same time, wasted heat is a form of pollution that threatens the environment. Another task for high power converters is efficient harvesting of renewable energy sources, such as the wind energy and the sun. Intermittent in nature, they pose a difficult task to power converter topology and controls. Eventually, high power converters are entering power distribution and transmission networks. With their quick reaction, with fast communication between the grid nodes and with advanced controllability of high power converters, a number of innovations can be introduced, facilitating the power system control and allowing for optimizations and loss reduction. Coined smart grid, this solution comprises two key elements, and these are intelligent controls and large static power converters. At virtually no cost, smart grids allow for a better utilization of available resources and it enlarges the stable operating range of the transmission systems. Therefore, it is of interest to review the

  12. 76 FR 53045 - Prevailing Rate Systems; Abolishment of Monmouth, NJ, as a Nonappropriated Fund Federal Wage...

    Science.gov (United States)

    2011-08-25

    ... 3206-AM49 Prevailing Rate Systems; Abolishment of Monmouth, NJ, as a Nonappropriated Fund Federal Wage System Wage Area AGENCY: U.S. Office of Personnel Management. ACTION: Interim rule with request for... Monmouth, New Jersey, nonappropriated fund (NAF) Federal Wage System (FWS) wage area and redefine Monmouth...

  13. Model predictive control of wind energy conversion systems

    CERN Document Server

    Yaramasu, Venkata Narasimha R

    2017-01-01

    The authors provide a comprehensive analysis on the model predictive control of power converters employed in a wide variety of variable-speed wind energy conversion systems (WECS). The contents of this book includes an overview of wind energy system configurations, power converters for variable-speed WECS, digital control techniques, MPC, modeling of power converters and wind generators for MPC design. Other topics include the mapping of continuous-time models to discrete-time models by various exact, approximate, and quasi-exact discretization methods, modeling and control of wind turbine grid-side two-level and multilevel voltage source converters. The authors also focus on the MPC of several power converter configurations for full variable-speed permanent magnet synchronous generator based WECS, squirrel-cage induction generator based WECS, and semi-variable-speed doubly fed induction generator based WECS.

  14. Modeling power electronics and interfacing energy conversion systems

    CERN Document Server

    Simões, Marcelo Godoy

    2017-01-01

    Discusses the application of mathematical and engineering tools for modeling, simulation and control oriented for energy systems, power electronics and renewable energy. This book builds on the background knowledge of electrical circuits, control of dc/dc converters and inverters, energy conversion and power electronics. The book shows readers how to apply computational methods for multi-domain simulation of energy systems and power electronics engineering problems. Each chapter has a brief introduction on the theoretical background, a description of the problems to be solved, and objectives to be achieved. Block diagrams, electrical circuits, mathematical analysis or computer code are covered. Each chapter concludes with discussions on what should be learned, suggestions for further studies and even some experimental work.

  15. Global health initiative investments and health systems strengthening: a content analysis of global fund investments.

    Science.gov (United States)

    Warren, Ashley E; Wyss, Kaspar; Shakarishvili, George; Atun, Rifat; de Savigny, Don

    2013-07-26

    Millions of dollars are invested annually under the umbrella of national health systems strengthening. Global health initiatives provide funding for low- and middle-income countries through disease-oriented programmes while maintaining that the interventions simultaneously strengthen systems. However, it is as yet unclear which, and to what extent, system-level interventions are being funded by these initiatives, nor is it clear how much funding they allocate to disease-specific activities - through conventional 'vertical-programming' approach. Such funding can be channelled to one or more of the health system building blocks while targeting disease(s) or explicitly to system-wide activities. We operationalized the World Health Organization health system framework of the six building blocks to conduct a detailed assessment of Global Fund health system investments. Our application of this framework framework provides a comprehensive quantification of system-level interventions. We applied this systematically to a random subset of 52 of the 139 grants funded in Round 8 of the Global Fund to Fight AIDS, Tuberculosis and Malaria (totalling approximately US$1 billion). According to the analysis, 37% (US$ 362 million) of the Global Fund Round 8 funding was allocated to health systems strengthening. Of that, 38% (US$ 139 million) was for generic system-level interventions, rather than disease-specific system support. Around 82% of health systems strengthening funding (US$ 296 million) was allocated to service delivery, human resources, and medicines & technology, and within each of these to two to three interventions. Governance, financing, and information building blocks received relatively low funding. This study shows that a substantial portion of Global Fund's Round 8 funds was devoted to health systems strengthening. Dramatic skewing among the health system building blocks suggests opportunities for more balanced investments with regard to governance, financing, and

  16. 77 FR 28471 - Prevailing Rate Systems; Abolishment of Montgomery, PA, as a Nonappropriated Fund Federal Wage...

    Science.gov (United States)

    2012-05-15

    ... 3206-AM62 Prevailing Rate Systems; Abolishment of Montgomery, PA, as a Nonappropriated Fund Federal... the Montgomery, Pennsylvania, nonappropriated fund (NAF) Federal Wage System (FWS) wage area and redefine Chester, Montgomery, and Philadelphia Counties, PA, to the Burlington, NJ, NAF wage area and...

  17. 76 FR 31785 - Prevailing Rate Systems; Abolishment of Cumberland, ME, as a Nonappropriated Fund Federal Wage...

    Science.gov (United States)

    2011-06-02

    ... Nonappropriated Fund Federal Wage System Wage Area AGENCY: U.S. Office of Personnel Management. ACTION: Interim... rule ] to abolish the Cumberland, Maine, nonappropriated fund (NAF) Federal Wage System (FWS) wage area and redefine Cumberland, Kennebec, and Penobscot Counties, ME, to the York, ME, NAF wage area...

  18. Building High-Performing and Improving Education Systems. Systems and Structures: Powers, Duties and Funding. Review

    Science.gov (United States)

    Slater, Liz

    2013-01-01

    This Review looks at the way high-performing and improving education systems share out power and responsibility. Resources--in the form of funding, capital investment or payment of salaries and other ongoing costs--are some of the main levers used to make policy happen, but are not a substitute for well thought-through and appropriate policy…

  19. Pay as you Go System versus Fully Funded Pension in Peru

    Directory of Open Access Journals (Sweden)

    Jorge B. Guillén

    2013-06-01

    Full Text Available The following paper analyses the sustainability of the Peruvian “Pay as You Go System” which is provided by the Government. In Peru, the “Pay as you Go System” coexists with Private Pension Funds or “Fully Funded Pension”. Sometimes both systems compete with each other with advantages and disadvantages between them. We found that “Pay as You Go System” cannot be sustainable over a long period of time. In addition, based on a comparative analysis of advantages and disadvantages, we propose some recommendations to make Private Pension Funds (Fully Funded Pension the best alternative to Pay as You Go System.

  20. Progress on PEP-II magnet power conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Bellomo, P.; Genova, L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Jackson, T. [Lawrence Berkeley National Lab., CA (United States); Shimer, D. [Lawrence Livermore National Lab., CA (United States)

    1996-06-04

    The various power systems for supplying the PEP-II DC magnets rely exclusively on switchmode conversion, utilizing a variety of means depending on the requirements. All of the larger power supplies, ranging from 10 to 200 kW, are powered from DC sources utilizing rectified 480 V AC. Choppers can be used for the series connected strings, but for smaller groups and individual magnets, inverters driving high-frequency transformers with rectifiers comprise the best approach. All of the various systems use a ``building block`` approach of multiple standard-size units connected in series or parallel to most cost-effectively deal with a great range of voltage and current requirements. Utilization of existing infrastructure from PEP-I has been a cost-effective determinant. Equipment is being purchased either off-the-shelf, through performance specification, or by hardware purchase based on design-through-prototype. The corrector magnet power system, utilizing inexpensive, off-the-shelf, four-quadrant switching motor-controllers, has already proven very reliable: 120 of the total of 900 units have been running on the injection system for four months with no failures.

  1. Why increasing longevity may favour a PAYG pension system over a funded system.

    Science.gov (United States)

    Ediev, Dalkhat M

    2014-03-01

    When pension systems are contrasted it is common to use simplified demographic models, such as overlapping generation models with time-invariant mortality. Breaking with this tradition, we show that for a population with increasing longevity, the pay-as-you-go (PAYG) system may be more advantageous than a funded system (FS). Increasing longevity favours the PAYG system because for the workers living longer at retirement than current retirees, it is less costly to fund others' current pensions than their own. At present, the effect amounts to around 15 per cent in terms of the dependency ratio, or six more years at work in the FS, or 1 per cent per annum in terms of the real interest rate. In most developed countries the effect substantially exceeds that of the usually studied biological interest rate.

  2. Methods for locating ground faults and insulation degradation condition in energy conversion systems

    Science.gov (United States)

    Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

    2015-08-11

    Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

  3. 77 FR 34854 - Prevailing Rate Systems; Special Wage Schedules for Nonappropriated Fund Automotive Mechanics

    Science.gov (United States)

    2012-06-12

    ... Schedules for Nonappropriated Fund Automotive Mechanics AGENCY: U.S. Office of Personnel Management. ACTION... fund (NAF) automotive mechanics. These special wage schedules would replace the current commission pay practice covering DOD's NAF automotive mechanics with a flat rate pay system. Implementation of a flat rate...

  4. Experimental model of a wind energy conversion system

    Science.gov (United States)

    Vasar, C.; Rat, C. L.; Prostean, O.

    2018-01-01

    The renewable energy domain represents an important issue for the sustainable development of the mankind in the actual context of increasing demand for energy along with the increasing pollution that affect the environment. A significant quota of the clean energy is represented by the wind energy. As a consequence, the developing of wind energy conversion systems (WECS) in order to achieve high energetic performances (efficiency, stability, availability, competitive cost etc) represents a topic of permanent actuality. Testing and developing of an optimized control strategy for a WECS direct implemented on a real energetic site is quite difficult and not cost efficient. Thus a more convenient solution consists in a flexible laboratory setup which requires an experimental model of a WECS. Such approach would allow the simulation of various real conditions very similar with existing energetic sites. This paper presents a grid-connected wind turbine emulator. The wind turbine is implemented through a real-time Hardware-in-the-Loop (HIL) emulator, which will be analyzed extensively in the paper. The HIL system uses software implemented in the LabVIEW programming environment to control an ABB ACS800 electric drive. ACS800 has the task of driving an induction machine coupled to a permanent magnet synchronous generator. The power obtained from the synchronous generator is rectified, filtered and sent to the main grid through a controlled inverter. The control strategy is implemented on a NI CompactRIO (cRIO) platform.

  5. Catalytic systems used for polymerization, biomass conversion, and enhancing diffusion

    Science.gov (United States)

    Pong, Frances

    A significant amount of research has been dedicated towards the study and improvement of catalysts. A better understanding of how catalysts work can lead to developing more cost-efficient catalytic systems for a variety of applications. My research is focuses on catalytic systems used in three different fields, which are (i) organometallic polymerization catalysts, (ii) molecular motors and (iii) biomass conversion. Researchers have long studied and modified organometallic catalysts for use in the direct co- and homopolymerization of monomers with polar functional groups. The ability to add polar moieties to polymers, which can potentially yield materials with a wider range of physical properties, is highly desirable. In this study (i), a series of naphthoxyimine palladium(II) catalysts -- in which the naphthyl backbone had been functionalized with different moieties -- were synthesized and systematically studied to determine the ligand structure's impact on catalytic activity. The study showed that slight modifications of the naphthyl backbone led to significant changes in the polymer's molecular weight and polydispersity index. The catalysts were also displayed some ability to co-polymerize ethylene and functionalized norbornene. These positive results suggest that further exploration of naphthoxyimine palladium (II) catalysts may be fundamentally interesting. The effect of active, motile particles at the nanoscale has been vigorously researched during the past decade. By understanding how such active suspensions behave, researchers can gain new insights which can potentially provide new applications in many fields. Here (ii) the momentum transfer of active catalysts (Grubbs' 2nd generation catalyst with a hydrodynamic radius of 6A) to their immediate surroundings is observed in an organic suspension. This phenomenon, which has been coined "enhanced diffusion," has not been well studied at the angstrom scale until now. Diffusion-NMR spectroscopy surprisingly

  6. Some exploratory considerations of scale effects on the potential performance of wood energy conversion systems

    Science.gov (United States)

    Eggers, A. J., Jr.; Smith, B. A.; Tombaugh, L. W.

    1982-06-01

    Scale effects on the potential performance of wood energy conversion systems whose products might compete in many of the same diverse and dispersed markets as comparable products from fossil fuels are explored. The analytical approach is derived from the average total cost formulation of micro-economics which is configured to account for the factors of total cost rate for wood production, transportation, and conversion in systems with a given conversion efficiency and capacity. The exploratory systems analysis includes: systems elements and cost formulation; area production and associated transportation; point production and associated transportation; conversion system capacity effects; conversion plant learning curve effects; subsystem disaggregation, staging, and production rate effects, and conversion plant financing effects.

  7. Variable-speed systems for higher efficiencies. ALSTOM Power Conversion; Drehzahlvariable Systeme verbessern die Effizienz. ALSTOM Power Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, S. [ALSTOM Power Conversion GmbH, Berlin (Germany)

    2002-07-01

    Variable-speed generators can enhance power generation efficiencies depending on the plant type and site. For example, an offshore wind power system in the North Sea can utilize stronger and more constant winds than a plant in a low inland mountain range, i.e. the demands on the plant itself will differ. A variable-speed drive is recommended which adapts the plant to the available wind and provides optimum power quality with maximum energy yield and availability. Optimum adjustment of the system components is a key prerequisite for this. The central components of the energy conversion system, i.e. the generators and current inverters, convert rotational energy of the rotors into electric power which is supplied to the public grid. Both components have been optimized continually by ALSTOM for many years and have been used successfully in many different systems. [German] Ein drehzahlgeregelter Generator ermoeglicht je nach Anlagentyp und Standort die Steigerung der Energieausbeute. Eine Offshore-Windkraftanlage in der Nordsee kann staerkere und dauerhaftere Winde als eine Anlage, die im Mittelgebirge aufgestellt ist, nutzen. Daraus ergeben sich unterschiedliche Anforderungen an die Windkraftanlage selbst. Gefragt ist eine Steuerung, die das gesamte Antriebssystem, einschliesslich der Rotorblaetter, optimal an die gegebene Windsituation anpasst. Als Loesung bietet sich ein drehzahlgeregeltes Antriebssystem an, das sich auf die jeweilige Windsituation einstellt und bei maximaler Energieausbeute und Verfuegbarkeit die bestmoegliche Stromqualitaet zur Verfuegung stellt. Eine wichtige Voraussetzung dafuer ist die optimale Abstimmung der Systemkomponenten. Die zentralen Komponenten des Energieumwandlungssystems - Generatoren und Stromrichter - sorgen in Windkraftanlagen fuer die Umwandlung der Rotationsenergie in elektrischen Storm, der ins Netz gespeist wird. Beide Komponenten werden von ALSTOM schon seit Jahren kontinuierlich optimiert und haben sich in einer Vielzahl

  8. Near-infrared (NIR) optogenetics using up-conversion system

    Science.gov (United States)

    Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Yawo, Hiromu

    2015-03-01

    Non-invasive remote control technologies designed to manipulate neural functions for a comprehensive and quantitative understanding of the neuronal network in the brain as well as for the therapy of neurological disorders have long been awaited. Recently, it has become possible to optically manipulate the neuronal activity using biological photo-reactive molecules such as channelrhodopsin-2 (ChR2). However, ChR2 and its relatives are mostly reactive to visible light which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light penetrates deep into the tissues because biological systems are almost transparent to light within this so-called `imaging window'. Here we used lanthanide nanoparticles (LNPs), which are composed of rare-earth elements, as luminous bodies to activate channelrhodopsins (ChRs) since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Neuron-glioma-hybrid ND-7/23 cells were cultured with LNP(NaYF4:Sc/Yb/Er) particles (peak emission, 543 nm) and transfected to express C1V1 (peak absorbance, 539 nm), a chimera of ChR1 and VChR1. The photocurrents were generated in response to NIR laser light (976 nm) to a level comparable to that evoked by a filtered Hg lamp (530-550 nm). NIR light pulses also evoked action potentials in the cultured neurons that expressed C1V1. It is suggested that the green luminescent light emitted from LNPs effectively activated C1V1 to generate the photocurrent. With the optimization of LNPs, acceptor photo-reactive biomolecules and optics, this system could be applied to non-invasively actuate neurons deep in the brain.

  9. Ultra-capacitors in power conversion systems analysis, modeling and design in theory and practice

    CERN Document Server

    Grbovic, Petar J

    2014-01-01

    Divided into five parts, this book is focused on ultra-capacitors and their applications in power conversion systems. It discusses ultra-capacitor analysis, modelling and module design from a macroscopic (application) perspective. It also describes power conversion applications, interface dc-dc converter design and entire conversion system design. Part One covers the background of energy storage technologies, with particular attention on state-of-the-art ultra-capacitor energy storage technologies. In Chapter four of this part, power conversion systems with integrated energy storage is discus

  10. Process systems engineering issues and applications towards reducing carbon dioxide emissions through conversion technologies

    DEFF Research Database (Denmark)

    Roh, Kosan; Frauzem, Rebecca; Gani, Rafiqul

    2016-01-01

    This paper reviews issues and applications for design of sustainable carbon dioxide conversion processes, specifically through chemical conversion, and the integration of the conversion processes with other systems from a process systems engineering (PSE) view-point. Systematic and computer......-aided methods and tools for reaction network generation, processing route generation, process design/optimization, and sustainability analysis are reviewed with respect to carbon dioxide conversion. Also, the relevant gaps and opportunities are highlighted. In addition, the integration of carbon dioxide...... conversion processes with other systems including coexisting infrastructure and carbon dioxide sources is described.Then, the importance of PSE based studies for such application is discussed. Finally, some perspectives on the status and future directions of carbon dioxide conversion technology...

  11. Summary of State-of-the-Art Power Conversion Systems for Energy Storage Applications

    Energy Technology Data Exchange (ETDEWEB)

    Atcitty, S.; Gray-Fenner, A.; Ranade, S.

    1998-09-01

    The power conversion system (PCS) is a vital part of many energy storage systems. It serves as the interface between the storage device, an energy source, and an AC load. This report summarizes the results of an extensive study of state-of-the-art power conversion systems used for energy storage applications. The purpose of the study was to investigate the potential for cost reduction and performance improvement in these power conversion systems and to provide recommendations for fiture research and development. This report provides an overview of PCS technology, a description of several state-of-the-art power conversion systems and how they are used in specific applications, a summary of four basic configurations for l:he power conversion systems used in energy storage applications, a discussion of PCS costs and potential cost reductions, a summary of the stancku-ds and codes relevant to the technology, and recommendations for future research and development.

  12. Chart of conversion factors: From English to metric system and metric to English system

    Science.gov (United States)

    ,

    1976-01-01

    The conversion factors in the following tables are for conversion of our customary (English) units of measurement to SI*units, and for convenience, reciprocals are shown for converting SI units back to the English system. The first table contains rule-of-thumb figures, useful for "getting the feel" of SI units or mental estimation. The succeeding tables contain factors accurate to 3 or more significant figures. Please refer to known reference volumes for additional accuracy, as well as for factors dealing with other scientific notation involving SI units.

  13. Novel, Integrated Reactor / Power Conversion System (LMR-AMTEC)

    Energy Technology Data Exchange (ETDEWEB)

    Pablo Rubiolo, Principal Investigator

    2003-03-21

    The main features of this project were the development of a long life (up to 10 years) Liquid Metal Reactor (LMR) and a static conversion subsystem comprising an Alkali Metal Thermal-to-Electric (AMTEC) topping cycle and a ThermoElectric (TE) Bottom cycle. Various coupling options of the LMR with the energy conversion subsystem were explored and, base in the performances found in this analysis, an Indirect Coupling (IC) between the LMR and the AMTEC/TE converters with Alkali Metal Boilers (AMB) was chosen as the reference design. The performance model of the fully integrated sodium-and potassium-AMTEC/TE converters shows that a combined conversion efficiency in excess of 30% could be achieved by the plant. (B204)

  14. Integrated bioenergy conversion concepts for small scale gasification power systems

    Science.gov (United States)

    Aldas, Rizaldo Elauria

    microorganisms used to deal with tars are selected and pre-conditioned to the tar environment. Overall, the results provided a basis for operational and design strategy for a combined gasification system but further study is recommended such as determination of the impacts in terms of emissions, power, efficiency and costs associated with the use of producer gas-enriched biogas taking advantage of hydrogen enrichment to reduce NOx and other pollutants in reciprocating engines and other energy conversion systems.

  15. Program Funding Guide for Air Force Systems Command Space Programs

    Science.gov (United States)

    1975-11-01

    Robert O’Shaughnessy, USN. My special thanks are also due Major Lawrence J. Hildebrand, Headquarters, Air Force Systems Command/ SDSD , for providing in...and Engineering. Washington, D.C., May 1974. 14. Hildebrand, Lawrence J., MAJ USAF., Interview conducted at Air Force Systems Command, AFSC/ SDSD . 12 August 1975. C-2 I

  16. Biomass Feedstock and Conversion Supply System Design and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, Jacob J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Roni, Mohammad S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lamers, Patrick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cafferty, Kara G. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Idaho National Laboratory (INL) supports the U.S. Department of Energy’s bioenergy research program. As part of the research program INL investigates the feedstock logistics economics and sustainability of these fuels. A series of reports were published between 2000 and 2013 to demonstrate the feedstock logistics cost. Those reports were tailored to specific feedstock and conversion process. Although those reports are different in terms of conversion, some of the process in the feedstock logistic are same for each conversion process. As a result, each report has similar information. A single report can be designed that could bring all commonality occurred in the feedstock logistics process while discussing the feedstock logistics cost for different conversion process. Therefore, this report is designed in such a way that it can capture different feedstock logistics cost while eliminating the need of writing a conversion specific design report. Previous work established the current costs based on conventional equipment and processes. The 2012 programmatic target was to demonstrate a delivered biomass logistics cost of $55/dry ton for woody biomass delivered to fast pyrolysis conversion facility. The goal was achieved by applying field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model. The goal of the 2017 Design Case is to enable expansion of biofuels production beyond highly productive resource areas by breaking the reliance of cost-competitive biofuel production on a single, low-cost feedstock. The 2017 programmatic target is to supply feedstock to the conversion facility that meets the in-feed conversion process quality specifications at a total logistics cost of $80/dry T. The $80/dry T. target encompasses total delivered feedstock cost, including both grower payment and logistics costs, while meeting all conversion in-feed quality targets

  17. The potential for matrix conversion in marine electric propulsion systems.

    OpenAIRE

    Ciaramella, K. M.

    2006-01-01

    The growing interest in marine electric propulsion is driven by the need to improve ship performance. This thesis presents a review of existing marine electric propulsion technology and potential future variable speed drives. The matrix converter was found to be a promising alternative to existing technology and this thesis describes an investigation into its potential for marine electric propulsion. The matrix converter performs direct AC-AC conversion using a high switching frequency to pro...

  18. Debugging the Conversion Process: Lessons from an Administrative Information System Conversion.

    Science.gov (United States)

    Hibbler, Fritz; Mitchell, Linda

    1995-01-01

    The process of reengineering the administrative information system at the University of Idaho required careful planning, development of a set of philosophies, and several strategies for ensuring success. The latter included a humorous symbol (a jitter bug) to express concern, improved institutional communications, and a focus on logistical issues.…

  19. The 'diagonal' approach to Global Fund financing: a cure for the broader malaise of health systems?

    Directory of Open Access Journals (Sweden)

    Baker Brook K

    2008-03-01

    Full Text Available Abstract Background The potentially destructive polarisation between 'vertical' financing (aiming for disease-specific results and 'horizontal' financing (aiming for improved health systems of health services in developing countries has found its way to the pages of Foreign Affairs and the Financial Times. The opportunity offered by 'diagonal' financing (aiming for disease-specific results through improved health systems seems to be obscured in this polarisation. In April 2007, the board of the Global Fund to fight AIDS, Tuberculosis and Malaria agreed to consider comprehensive country health programmes for financing. The new International Health Partnership Plus, launched in September 2007, will help low-income countries to develop such programmes. The combination could lead the Global Fund to fight AIDS, Tuberculosis and Malaria to a much broader financing scope. Discussion This evolution might be critical for the future of AIDS treatment in low-income countries, yet it is proposed at a time when the Global Fund to fight AIDS, Tuberculosis and Malaria is starved for resources. It might be unable to meet the needs of much broader and more expensive proposals. Furthermore, it might lose some of its exceptional features in the process: its aim for international sustainability, rather than in-country sustainability, and its capacity to circumvent spending restrictions imposed by the International Monetary Fund. Summary The authors believe that a transformation of the Global Fund to fight AIDS, Tuberculosis and Malaria into a Global Health Fund is feasible, but only if accompanied by a substantial increase of donor commitments to the Global Fund. The transformation of the Global Fund into a 'diagonal' and ultimately perhaps 'horizontal' financing approach should happen gradually and carefully, and be accompanied by measures to safeguard its exceptional features.

  20. 5 CFR 9901.231 - Conversion of positions and employees to NSPS classification system.

    Science.gov (United States)

    2010-01-01

    ... in a pay band based on the level of work of the employee's position in the formerly applicable pay... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Conversion of positions and employees to... Provisions § 9901.231 Conversion of positions and employees to NSPS classification system. (a) Introduction...

  1. 77 FR 63205 - Prevailing Rate Systems; Abolishment of Montgomery, Pennsylvania, as a Nonappropriated Fund...

    Science.gov (United States)

    2012-10-16

    ... RIN 3206-AM62 Prevailing Rate Systems; Abolishment of Montgomery, Pennsylvania, as a Nonappropriated.... SUMMARY: The U.S. Office of Personnel Management is issuing a final rule to abolish the Montgomery, Pennsylvania, nonappropriated fund (NAF) Federal Wage System (FWS) wage area and redefine Chester, Montgomery...

  2. 77 FR 26245 - Household Water Well System Grant Program Announcement of Application Deadlines and Funding

    Science.gov (United States)

    2012-05-03

    ... with low to moderate incomes finance the costs of household water wells that they own or will own. The... Rural Utilities Service Household Water Well System Grant Program Announcement of Application Deadlines... in grant funds to be competitively awarded for the Household Water Well System (HWWS) Grant Program...

  3. 77 FR 11383 - Prevailing Rate Systems; Abolishment of Monmouth, NJ, as a Nonappropriated Fund Federal Wage...

    Science.gov (United States)

    2012-02-27

    ... Wage System Wage Area AGENCY: U.S. Office of Personnel Management. ACTION: Final rule. SUMMARY: The U.S..., nonappropriated fund (NAF) Federal Wage System (FWS) wage area and redefine Monmouth County, NJ, to the Burlington, NJ, NAF wage area. These changes are necessary because the closure of Fort Monmouth left the Monmouth...

  4. 45 CFR 1355.52 - Funding authority for statewide automated child welfare information systems (SACWIS).

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Funding authority for statewide automated child welfare information systems (SACWIS). 1355.52 Section 1355.52 Public Welfare Regulations Relating to... welfare information systems (SACWIS). (a) States may receive Federal reimbursement at the 75 percent match...

  5. Scientific-theoretical principles of the functioning insurance and funded pension system models

    Directory of Open Access Journals (Sweden)

    L. Khachumova

    2015-01-01

    Full Text Available Retracted articleThe main value of the pension system in the world is to improve the living standards of citizens in old age, and income replacement by smoothing consumption function. The article reveals the scien tific and theoretical apparatus and operation of the insurance models and funded pension system at the country level.

  6. Power conversion distribution system using a resonant high-frequency AC link

    Science.gov (United States)

    Sood, P. K.; Lipo, T. A.

    1986-01-01

    Static power conversion systems based on a resonant high frequency (HF) link offers a significant reduction in the size and weight of the equipment over that achieved with conventional approaches, especially when multiple sources and loads are to be integrated. A faster system response and absence of audible noise are the other principal characteristics of such systems. A conversion configuration based on a HF link which is suitable for applications requiring distributed power is proposed.

  7. The principles of electronic and electromechanic power conversion a systems approach

    CERN Document Server

    Ferreira, Braham

    2013-01-01

    Teaching the principles of power electronics and electromechanical power conversion through a unique top down systems approach, The Principles of Electromechanical Power Conversion takes the role and system context of power conversion functions as the starting point. Following this approach, the text defines the building blocks of the system and describes the theory of how they exchange power with each other. The authors introduce a modern, simple approach to machines, which makes the principles of field oriented control and space vector theory approachable to undergraduate students as well as

  8. The Design of the Rhode Island School Funding Formula: Toward a Coherent System of Allocating State Aid to Public Schools

    Science.gov (United States)

    Wong, Kenneth K.

    2011-01-01

    Reforming the way a state distributes its funding to local school districts is clearly a challenging task. This paper presents the Rhode Island story on school funding reform. First, the paper begins with a short history of Rhode Island's school finance system and the key factors that called for school funding reform. Second, the paper discusses…

  9. Evaluation of KFB-funded research on transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, D.; Knudsen, T.; Wegener, M.

    1999-09-01

    This report presents an evaluation of two research projects on transport systems, which have been financed fully or partially by KFB. The projects are: l. Systems analysis of transport markets at the Division of Transport and Location Analysis in the Department of Infrastructure and Planning of the Royal Institute of Technology, Stockholm; and 2. Planning, analysis and management in traffic networks - optimization models and methods at the Division of Optimization in the Department of Mathematics at Linkoeping University. The evaluation seeks to examine the scientific quality of the research and its relevance to the academic world and society. The two project teams prepared a self-assessment of their research activities and submitted copies of relevant publications. The evaluation committee visited both institutions and engaged the teams in discussions of their results and methodology. These visits occurred on June 1 and 2, 1999. This report is based on the self-assessments of the teams, the materials submitted and the meetings with the project teams. The evaluation and recommendations presented in the report are those of the reviewers and do not necessarily represent the views of KFB

  10. Request for Travel Funds for Systems Radiation Biology Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [NYU School of Medicine

    2014-03-22

    The 3rd International Systems Radiation Biology Workshop brought together the major European, US and Japanese research programs on radiation risk as well as selected experts representing systems biological approaches to discuss how the new methodologies could be best exploited for low dose research. A significant part of the workshop was devoted to discussions organised as breakout group sessions. To facilitate discussions number of participants was limited to 60 persons. To achieve the goals of this symposium in this international conference, support from DOE is vital. Hence, this proposal requested support in the amount of $15,000 to cover the travel expenses of international experts and radiation biology scientists from the United States. This supporting mechanism was clearly identified to the selected US participants as a conference support award from the DOE (See attached PDF). The workshop was an outstanding opportunity to strengthen interactions between leading experts in the emerging areas of radiation sciences, and will also provide opportunities for younger scientists to meet with experts and discuss their results. This workshop was designed to endorse active engagement in international collaboration. A major objective of this conference was to effectively communicate research results, in order to ensure that current thinking reflects sound science of radiation biology. Further, this international event addressed the use and success of scientific initiatives in radiation biology for policymakers, standard-setters, and the general public.

  11. Energy Storage System with Voltage Equalization Strategy for Wind Energy Conversion

    Directory of Open Access Journals (Sweden)

    Cheng-Tao Tsai

    2012-07-01

    Full Text Available In this paper, an energy storage system with voltage equalization strategy for wind energy conversion is presented. The proposed energy storage system provides a voltage equalization strategy for series-connected lead-acid batteries to increase their total storage capacity and lifecycle. In order to draw the maximum power from the wind energy, a perturbation-and-observation method and digital signal processor (DSP are incorporated to implement maximum power point tracking (MPPT algorithm and power regulating scheme. In the proposed energy storage system, all power switches have zero-voltage-switching (ZVS feature at turn-on transition. Therefore, the conversion efficiency can be increased. Finally, a prototype energy storage system for wind energy conversion is built and implemented. Experimental results have verified the performance and feasibility of the proposed energy storage system for wind energy conversion.

  12. An Integrated System for the Treatment of Coal Conversion Wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Henry Y. Wang; Keeran R. Srinivasan

    1999-02-25

    Treatment of mixed waste from coal conversion wastewaters involves the degradation of toxic organics and the removal of heavy metals. An integrated and cost-effective treatment scheme that can implement such a process is considered essential to promote continued development and growth of coal conversion processes without any deleterious effects on our ecosystem. We have recently developed a pH-dependent, reversible heavy metal adsorption/desorption process which promises to be a cost-effective alternative to the treatment and disposal options currently in place for these inorganic contaminants. Our work shows that: (1) Polydisperse, industrial-grade surfactants can be used in the development of novel, surfactant-coated smectitic clays containing up to 50% by weight of adsorbed surfactant, (2) Reversible adsorption and resorption of cationic (CU(II) and Cd(II)) and anionic (Cr(VI)) heavy metals from their respective aqueous solutions onto these surfactant-modified smectites can be effected using pH of the medium as a switch, and (3) These surfactant-modified smectites can be repeatedly used (up to 5 times) with only a minimal loss in their adsorption potency and with very little leaching of the adsorbed surfactants.

  13. Funding of Graduate Medical Education in a Market-Based Healthcare System.

    Science.gov (United States)

    Schuster, Barbara L

    2017-02-01

    The graduate medical education (GME) process in the United States is considered the most respected model for high-quality education of graduate physicians in the world. With substantial funding through government and private insurers and through structured educational accreditation standards, the American Board of Medical Specialists-certified physicians are recognized for their expertise in delivering high-quality medical care. However, under fiscal constraints and changing social expectations, questions are continually posed about the process of funding and whether the "physician outcomes" are sufficient to continue with the investment. This article reviews the history of postgraduate physician education, the multiple funding pathways, disruptions to a placid educational system and changing social expectations. The ultimate issues involve the core goals of GME and how much GME should shoulder responsibility for changing the healthcare system. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  14. Development of Electro-Microbial Carbon Capture and Conversion Systems

    KAUST Repository

    Al Rowaihi, Israa S.

    2017-05-01

    Carbon dioxide is a viable resource, if used as a raw material for bioprocessing. It is abundant and can be collected as a byproduct from industrial processes. Globally, photosynthetic organisms utilize around 6’000 TW (terawatt) of solar energy to fix ca. 800 Gt (gigaton) of CO2 in the planets largest carbon-capture process. Photosynthesis combines light harvesting, charge separation, catalytic water splitting, generation of reduction equivalents (NADH), energy (ATP) production and CO2 fixation into one highly interconnected and regulated process. While this simplicity makes photosynthetic production of commodity interesting, yet photosynthesis suffers from low energy efficiency, which translates in an extensive footprint for solar biofuels production conditions that store < 2% of solar energy. Electron transfer processes form the core of photosynthesis. At moderate light intensity, the electron transport chains reach maximum transfer rates and only work when photons are at appropriate wavelengths, rendering the process susceptible to oxidative damage, which leads to photo-inhibition and loss of efficiency. Based on our fundamental analysis of the specialized tasks in photosynthesis, we aimed to optimize the efficiency of these processes separately, then combine them in an artificial photosynthesis (AP) process that surpasses the low efficiency of natural photosynthesis. Therefore, by combining photovoltaic light harvesting with electrolytic water splitting or CO2 reduction in combination with microbiological conversion of electrochemical products to higher valuable compounds, we developed an electro-microbial carbon capture and conversion setups that capture CO2 into the targeted bioplastic; polyhydroxybutyrate (PHB). Based on the type of the electrochemical products, and the microorganism that either (i) convert products formed by electrochemical reduction of CO2, e.g. formate (using inorganic cathodes), or (ii) use electrochemically produced H2 to reduce CO2

  15. Energy and data conversion circuits for low power sensory systems

    Science.gov (United States)

    Ghosh, Suvradip

    This dissertation focuses on the problem of increasing the lifetime of wireless sensors. This problem is addressed from two different angles: energy harvesting and data compression. Energy harvesting enables a sensor to extract energy from its environment and use it to power itself or recharge its batteries. Data compression, on the other hand, allows a sensor to save energy by reducing the radio transmission bandwidth. This dissertation proposes a fractal-based photodiode fabricated on standard CMOS process as an energy harvesting device with increased efficiency. Experiments show that, the fractal based photodiodes are 6% more efficient compared to the conventional square shaped photodiode. The fractal shape photodiode has more perimeter-to-area ratio which increases the lateral response, improving its efficiency. With increased efficiency, more current is generated but the open-circuit voltage still remains low (0.3V--0.45V depending on illumination condition). These voltages have to be boosted up to higher values if they are going to be used to power up any sensory circuit or recharge a battery. We propose a switched-inductor DC-DC converter to boost the low voltage of the photodiodes to higher voltages. The proposed circuit uses two on-chip switches and two off-chip Components: an inductor and a capacitor. Experiments show a voltage up to 2.81V can be generated from a single photodiode of 1mm2 area. The voltage booster circuit achieved a conversion efficiency of 59%. Data compression was also explored in an effort to reduce energy consumption during radio transmission. An analog-to-digital converter (ADC), which can jointly perform the tasks of digital conversion and entropy encoding, has also been proposed in this dissertation. The joint data conversion/compression help savings in area and power resources, making it suitable for on-sensor compression. The proposed converter combines a cyclic converter architecture and Golomb-Rice entropy encoder. The

  16. Green farming systems for the Southeast USA using manure-to-energy conversion platforms

    Science.gov (United States)

    Livestock operations in the Southeastern USA are faced with implementing holistic solutions to address effective manure treatment through efficient energy management and safeguarding of supporting natural resources. By integrating waste-to-energy conversion platforms, future green farming systems ca...

  17. In-grid solar-to-electrical energy conversion system modeling and testing

    OpenAIRE

    Čorba Zoltan J.; Katić Vladimir A.; Dumnić Boris P.; Milićević Dragan M.

    2012-01-01

    In this study, a simulation model of in-grid solar-to-electrical energy conversion system is presented. In this case, the in-grid solar-to-electrical energy conversion system is small photovoltaic power plant, which was constructed by the Center for Renewable Energy and Power Quality from Faculty of Technical Sciences (FTS). Equivalent circuit diagram of photovoltaic cell is described which was used to develop the simulation model of modules. Possible types...

  18. 45 CFR 1355.55 - Review and assessment of the system developed with enhanced funds.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Review and assessment of the system developed with enhanced funds. 1355.55 Section 1355.55 Public Welfare Regulations Relating to Public Welfare (Continued... CHILDREN, YOUTH AND FAMILIES, FOSTER CARE MAINTENANCE PAYMENTS, ADOPTION ASSISTANCE, AND CHILD AND FAMILY...

  19. Critical interactions between the Global Fund-supported HIV programs and the health system in Ghana

    DEFF Research Database (Denmark)

    Atun, Rifat; Pothapregada, Sai Kumar; Kwansah, Janet

    2011-01-01

    of the strengths and weaknesses of the relationship between Global Fund-supported activities and the health system and to identify positive synergies and unintended consequences of integration. Ghana has a well-functioning sector-wide approach to financing its health system, with a strong emphasis on integrated...... exponentially. Global Fund-supported activities have been well integrated into key health system functions to strengthen them, especially financing, planning, service delivery, and demand generation. Yet, with governance and monitoring and evaluation functions, parallel structures to national systems have......The support of global health initiatives in recipient countries has been vigorously debated. Critics are concerned that disease-specific programs may be creating vertical and parallel service delivery structures that to some extent undermine health systems. This case study of Ghana aimed to explore...

  20. The health systems funding platform and World Bank legacy: the gap between rhetoric and reality.

    Science.gov (United States)

    Brown, Scott S; Sen, Kasturi; Decoster, Kristof

    2013-03-06

    Global health partnerships created to encourage funding efficiencies need to be approached with some caution, with claims for innovation and responsiveness to development needs based on untested assumptions around the potential of some partners to adapt their application, funding and evaluation procedures within these new structures. We examine this in the case of the Health Systems Funding Platform, which despite being set up some three years earlier, has stalled at the point of implementation of its key elements of collaboration. While much of the attention has been centred on the suspension of the Global Fund's Round 11, and what this might mean for health systems strengthening and the Platform more broadly, we argue that inadequate scrutiny has been made of the World Bank's contribution to this partnership, which might have been reasonably anticipated based on an historical analysis of development perspectives. Given the tensions being created by the apparent vulnerability of the health systems strengthening agenda, and the increasing rhetoric around the need for greater harmonization in development assistance, an examination of the positioning of the World Bank in this context is vital.

  1. Experimental Study of Heat Energy Absorber with Porous Medium for Thermoelectric Conversion System

    Directory of Open Access Journals (Sweden)

    Tzer-Ming Jeng

    2013-12-01

    Full Text Available The thermoelectric conversion system usually consists of the heat absorber, the thermoelectric generator (TEG and the heat sink, while the heat absorber collects the heat to increase the temperature on the hot surface of TEG and enhances the generating electricity. This study experimentally investigated the performance of the brass-beads packed-bed heat absorber for the thermoelectric conversion system. The packed-bed heat absorber is installed in a square channel with the various flow orientation systems and the small ratio of channel width to bead diameter. The flow orientation systems included the straight flow and jet flow systems. This study showed the local and average heat transfer characteristics for various parameters. The experimental results can be the base of designs for the novel porous heat absorber of the thermoelectric conversion system.

  2. Characterization of solid-waste conversion and cogeneration systems

    Energy Technology Data Exchange (ETDEWEB)

    Ritschard, R.L.; Haven, K.F.; Henriquez, M.; Kay, J.; Walzer, W.

    1978-08-15

    Recovery of municipal solid wastes (MSW) can reduce the mass of landfilled wastes by as much as 95% and can tap a vast new energy resource. The yearly collection of MSW is estimated to be 125 million tons nationwide. Three basic technologies for recovering energy from MSW are considered, namely: direct combustion using a waterwall incinerator in which heat from burning refuse is converted to steam by circulating water in steel tubes jacketing the interior of the incinerator; manufacture of a relatively uniform shredded, pulverized, or pelleted refuse-derived fuel for supplemental firing in a utility boiler; and pyrolysis or destructive distillation of MSW to extract a low-Btu fuel gas. While resource and energy recovery systems can be installed independently, the processes described here include both energy and resource-recovery systems as well as necessary pollution-control equipment for gaseous emissions. Three end-use applications of cogeneration systems are characterized, including: fluidized-bed cogeneration systems for use in the pulp and paper industry; diesel system using the digested sewage gas of a sewage treatment plant for electricity generation as well as heating and pumping; and an enhanced oil recovery system. Comparisons are made of system inputs per 10/sup 12/ Btu steam output for Landguard pyrolysis, Garrett flash pyrolysis, Union Carbide Purox process, direct combustion, refuse-derived fuels, fluidized-bed cogeneration, diesel cogeneration, and enhanced oil recovery (cogeneration). The RFD system is by far the cheapest to build and is also the most efficient in terms of energy recovery per ton of MSW. The fluidized-bed system has the highest overall system efficiency. However, the PUROX system uses the least ancillary energy and is the only system not requiring an input water flow. Thus the RFD is the most favorable for capital inputs and the PUROX is the most favorable for operational inputs.

  3. Preservice Mathematics Teachers' Solutions to Problems: Conversions within the Metric System

    OpenAIRE

    Jean E. Hallagan

    2013-01-01

    This paper reports on the results of a preliminary investigation to determine if preservice mathematics teachers solve conversion problems within the metric system in multiple ways. Here, four metric conversion problems of escalating difficulty were administered within a mathematics methods course at a comprehensive state university in the Northeastern United States. Results show that preservice teachers solved the problems in the same way that they were taught in high school, and that in hig...

  4. Online optimization of a multi-conversion-level DC home microgrid for system efficiency enhancement

    DEFF Research Database (Denmark)

    Boscaino, V.; Guerrero, J. M.; Ciornei, I.

    2017-01-01

    In this paper, an on-line management system for the optimal efficiency operation of a multi-bus DC home distribution system is proposed. The operation of the system is discussed with reference to a distribution system with two conversion stages and three voltage levels. In each of the conversion...... stages, three paralleled DC/DC converters are implemented. A Genetic Algorithm performs the on-line optimization of the DC network’s global efficiency, generating the optimal current sharing ratios of the concurrent power converters. The overall DC/DC conversion system including the optimization section...... for, such as: components loss parameters, components ageing, load currents, switching frequency and input voltage. Simulation results considering several case studies are presented and the benefits brought by the optimization algorithm in terms of power saving are widely discussed for each case study....

  5. The Health Systems Funding Platform: Is this where we thought we were going?

    Directory of Open Access Journals (Sweden)

    Ooms Gorik

    2011-05-01

    Full Text Available Abstract Background In March 2009, the Task Force for Innovative International Financing for Health Systems recommended "a health systems funding platform for the Global Fund, GAVI Alliance, the World Bank and others to coordinate, mobilize, streamline and channel the flow of existing and new international resources to support national health strategies." Momentum to establish the Health Systems Funding Platform was swift, with the World Bank convening a Technical Workshop on Health Systems Strengthening (HSS, and serial meetings organized to progress the agenda. Despite its potential significance, there has been little comment in peer-reviewed literature, though some disquiet in the international development community around the scope of the Platform and the capacity of the partners, which appears disproportionate to the available information. Methods This case study uses documentary analysis, participant observation and 24 in-depth interviews to examine the processes of development and key issues raised by the Platform. Results The findings show a fluid and volatile process, with debate over whether ongoing engagement in HSS by Global Fund and GAVI represents a dilution of organizational focus, risking ongoing support, or a paradigm shift that facilitates the achievement of targeted objectives, builds systems capacity, and will attract additional resources. Uncertainty in the development of the Platform reflects the flexibility of the recently formed global health initiatives, and the instability of donor commitments, particularly in the current financial climate. But implicit in the conflict is tension between key global stakeholders over defining and ownership of the health systems agenda. Conclusions The tensions appear to have been resolved through a focus on national planning, applying International Health Partnership principles, though the global financial crisis and key personnel changes may yet alter outcomes. Despite its dynamic

  6. The Health Systems Funding Platform: Is this where we thought we were going?

    Science.gov (United States)

    2011-01-01

    Background In March 2009, the Task Force for Innovative International Financing for Health Systems recommended "a health systems funding platform for the Global Fund, GAVI Alliance, the World Bank and others to coordinate, mobilize, streamline and channel the flow of existing and new international resources to support national health strategies." Momentum to establish the Health Systems Funding Platform was swift, with the World Bank convening a Technical Workshop on Health Systems Strengthening (HSS), and serial meetings organized to progress the agenda. Despite its potential significance, there has been little comment in peer-reviewed literature, though some disquiet in the international development community around the scope of the Platform and the capacity of the partners, which appears disproportionate to the available information. Methods This case study uses documentary analysis, participant observation and 24 in-depth interviews to examine the processes of development and key issues raised by the Platform. Results The findings show a fluid and volatile process, with debate over whether ongoing engagement in HSS by Global Fund and GAVI represents a dilution of organizational focus, risking ongoing support, or a paradigm shift that facilitates the achievement of targeted objectives, builds systems capacity, and will attract additional resources. Uncertainty in the development of the Platform reflects the flexibility of the recently formed global health initiatives, and the instability of donor commitments, particularly in the current financial climate. But implicit in the conflict is tension between key global stakeholders over defining and ownership of the health systems agenda. Conclusions The tensions appear to have been resolved through a focus on national planning, applying International Health Partnership principles, though the global financial crisis and key personnel changes may yet alter outcomes. Despite its dynamic evolution, the Platform may offer

  7. Double barrier system for an in situ conversion process

    Energy Technology Data Exchange (ETDEWEB)

    McKinzie, Billy John [Houston, TX; Vinegar, Harold J [Bellaire, TX; Cowan, Kenneth Michael [Sugar land, TX; Deeg, Wolfgang Friedrich Johann [Houston, TX; Wong, Sau-Wai [Rijswijk, NL

    2009-05-05

    A barrier system for a subsurface treatment area is described. The barrier system includes a first barrier formed around at least a portion of the subsurface treatment area. The first barrier is configured to inhibit fluid from exiting or entering the subsurface treatment area. A second barrier is formed around at least a portion of the first barrier. A separation space exists between the first barrier and the second barrier.

  8. Rectenna System Design. [energy conversion solar power satellites

    Science.gov (United States)

    Woodcock, G. R.; Andryczyk, R. W.

    1980-01-01

    The fundamental processes involved in the operation of the rectenna system designed for the solar power satellite system are described. The basic design choices are presented based on the desired microwave rf field concentration prior to rectification and based on the ground clearance requirements for the rectenna structure. A nonconcentrating inclined planar panel with a 2 meter minimum clearance configuration is selected as a representative of the typical rectenna.

  9. Photoelectrochemical based direct conversion systems for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Khaselev, O.; Bansal, A.; Kocha, S.; Turner, J.A. [National Renewable Energy Lab., Golden, CO (United States)

    1998-08-01

    With an eye towards developing a photoelectrochemical system for hydrogen production using sunlight as the only energy input, two types of systems were studied, both involving multijunction devices. One set of cells consisted of a-Si triple junctions and the other a GaInP{sub 2}/GaAs tandem cell combination. Additional investigations were carried out on semiconductor surface modifications to move semiconductor band edges to more favorable energetic positions.

  10. 77 FR 19521 - Prevailing Rate Systems; Redefinition of the Austin, TX and Waco, TX, Appropriated Fund Federal...

    Science.gov (United States)

    2012-04-02

    ... 3206-AM50 Prevailing Rate Systems; Redefinition of the Austin, TX and Waco, TX, Appropriated Fund... of the Austin, TX, and Waco, TX, appropriated fund Federal Wage System (FWS) wage areas. The final rule redefines Burleson and Lampasas Counties, TX, from the Austin wage area to the Waco wage area...

  11. 76 FR 70365 - Prevailing Rate Systems; Redefinition of the Austin, TX and Waco, TX, Appropriated Fund Federal...

    Science.gov (United States)

    2011-11-14

    ... Austin, TX and Waco, TX, Appropriated Fund Federal Wage System Wage Areas AGENCY: U.S. Office of... Waco, TX, appropriated fund Federal Wage System (FWS) wage areas. The proposed rule would redefine Burleson and Lampasas Counties, TX, from the Austin wage area to the Waco wage area. These changes are...

  12. Testing of an advanced thermochemical conversion reactor system

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    This report presents the results of work conducted by MTCI to verify and confirm experimentally the ability of the MTCI gasification process to effectively generate a high-quality, medium-Btu gas from a wider variety of feedstock and waste than that attainable in air-blown, direct gasification systems. The system's overall simplicity, due to the compact nature of the pulse combustor, and the high heat transfer rates attainable within the pulsating flow resonance tubes, provide a decided and near-term potential economic advantage for the MTCI indirect gasification system. The primary objective of this project was the design, construction, and testing of a Process Design Verification System for an indirectly heated, thermochemical fluid-bed reactor and a pulse combustor an an integrated system that can process alternative renewable sources of energy such as biomass, black liquor, municipal solid waste and waste hydrocarbons, including heavy oils into a useful product gas. The test objectives for the biomass portion of this program were to establish definitive performance data on biomass feedstocks covering a wide range of feedstock qualities and characteristics. The test objectives for the black liquor portion of this program were to verify the operation of the indirect gasifier on commercial black liquor containing 65 percent solids at several temperature levels and to characterize the bed carbon content, bed solids particle size and sulfur distribution as a function of gasification conditions. 6 refs., 59 figs., 29 tabs.

  13. Rice Pricing during Organic Conversion of the Honghe Hani Rice Terrace System in China

    Directory of Open Access Journals (Sweden)

    Moucheng Liu

    2018-01-01

    Full Text Available In 2002, the United Nations Food and Agriculture Organization initiated the Globally Important Agriculture Heritage Systems conservation program. Agricultural organic certification, based on traditional environmentally friendly technology, increases farmer income and encourages traditional agricultural heritage. However, during the organic conversion period, farmer income cannot be guaranteed; this period is also a bottleneck for heritage conservation via organic certification. Based on experiences at the Honghe Hani rice terrace system in Yunnan, China, we calculated and compared inputs and outputs of traditional and modern systems during organic conversion and developed a calculation method for determining opportunity costs of agricultural production. We found that the stability of farmer income during conversion can be guaranteed by setting the protective purchasing price at 6.93 CNY/kg, thereby achieving the goal of dynamic conservation of agricultural heritage systems.

  14. Limits to solar power conversion efficiency with applications to quantum and thermal systems

    Science.gov (United States)

    Byvik, C. E.; Buoncristiani, A. M.; Smith, B. T.

    1983-01-01

    An analytical framework is presented that permits examination of the limit to the efficiency of various solar power conversion devices. Thermodynamic limits to solar power efficiency are determined for both quantum and thermal systems, and the results are applied to a variety of devices currently considered for use in space systems. The power conversion efficiency for single-threshold energy quantum systems receiving unconcentrated air mass zero solar radiation is limited to 31 percent. This limit applies to photovoltaic cells directly converting solar radiation, or indirectly, as in the case of a thermophotovoltaic system. Photoelectrochemical cells rely on an additional chemical reaction at the semiconductor-electrolyte interface, which introduces additional second-law demands and a reduction of the solar conversion efficiency. Photochemical systems exhibit even lower possible efficiencies because of their relatively narrow absorption bands. Solar-powered thermal engines in contact with an ambient reservoir at 300 K and operating at maximum power have a peak conversion efficiency of 64 percent, and this occurs for a thermal reservoir at a temperature of 2900 K. The power conversion efficiency of a solar-powered liquid metal magnetohydrodydnamic generator, a solar-powered steam turbine electric generator, and an alkali metal thermoelectric converter is discussed.

  15. Harvesting and Conversation in a Predator-Prey System

    NARCIS (Netherlands)

    Hoekstra, Jeljer; Bergh, van den Jeroen C.J.M.

    2001-01-01

    Optimal harvesting of prey in a predator-prey ecosystem is studiedunder the condition that the existence of the predator has value. Predators (birds) and humans (fishers) compete for prey (shellfish). The behavior of the system is studied and conditions for optimal control are deduced. Various

  16. Solid waste information and tracking system client-server conversion project management plan

    Energy Technology Data Exchange (ETDEWEB)

    May, D.L.

    1998-04-15

    This Project Management Plan is the lead planning document governing the proposed conversion of the Solid Waste Information and Tracking System (SWITS) to a client-server architecture. This plan presents the content specified by American National Standards Institute (ANSI)/Institute of Electrical and Electronics Engineers (IEEE) standards for software development, with additional information categories deemed to be necessary to describe the conversion fully. This plan is a living document that will be reviewed on a periodic basis and revised when necessary to reflect changes in baseline design concepts and schedules. This PMP describes the background, planning and management of the SWITS conversion. It does not constitute a statement of product requirements. Requirements and specification documentation needed for the SWITS conversion will be released as supporting documents.

  17. Expanding Learning and Social Interaction through Intelligent Systems Design: Implementing a Reputation and Recommender System for the Claremont Conversation Online

    Science.gov (United States)

    Thoms, Brian

    2009-01-01

    In this dissertation I examine the design, construction and implementation of an online blog ratings and user recommender system for the Claremont Conversation Online (CCO). In line with constructivist learning models and practical information systems (IS) design, I implemented a blog ratings system (a system that can be extended to allow for…

  18. Energy harvesting solar, wind, and ocean energy conversion systems

    CERN Document Server

    Khaligh, Alireza

    2009-01-01

    Also called energy scavenging, energy harvesting captures, stores, and uses ""clean"" energy sources by employing interfaces, storage devices, and other units. Unlike conventional electric power generation systems, renewable energy harvesting does not use fossil fuels and the generation units can be decentralized, thereby significantly reducing transmission and distribution losses. But advanced technical methods must be developed to increase the efficiency of devices in harvesting energy from environmentally friendly, ""green"" resources and converting them into electrical energy.Recognizing t

  19. Topological Frequency Conversion in Strongly Driven Quantum Systems

    Directory of Open Access Journals (Sweden)

    Ivar Martin

    2017-10-01

    Full Text Available When a physical system is subjected to a strong external multifrequency drive, its dynamics can be conveniently represented in the multidimensional Floquet lattice. The number of Floquet lattice dimensions equals the number of irrationally-related drive frequencies, and the evolution occurs in response to a built-in effective “electric” field, whose components are proportional to the corresponding drive frequencies. The mapping allows us to engineer and study temporal analogs of many real-space phenomena. Here, we focus on the specific example of a two-level system under a two-frequency drive that induces topologically nontrivial band structure in the 2D Floquet space. The observable consequence of such a construction is the quantized pumping of energy between the sources with frequencies ω_{1} and ω_{2}. When the system is initialized into a Floquet band with the Chern number C, the pumping occurs at a rate P_{12}=-P_{21}=(C/2πℏω_{1}ω_{2}, an exact counterpart of the transverse current in a conventional topological insulator.

  20. Foreign Language Tutoring in Oral Conversations Using Spoken Dialog Systems

    Science.gov (United States)

    Lee, Sungjin; Noh, Hyungjong; Lee, Jonghoon; Lee, Kyusong; Lee, Gary Geunbae

    Although there have been enormous investments into English education all around the world, not many differences have been made to change the English instruction style. Considering the shortcomings for the current teaching-learning methodology, we have been investigating advanced computer-assisted language learning (CALL) systems. This paper aims at summarizing a set of POSTECH approaches including theories, technologies, systems, and field studies and providing relevant pointers. On top of the state-of-the-art technologies of spoken dialog system, a variety of adaptations have been applied to overcome some problems caused by numerous errors and variations naturally produced by non-native speakers. Furthermore, a number of methods have been developed for generating educational feedback that help learners develop to be proficient. Integrating these efforts resulted in intelligent educational robots — Mero and Engkey — and virtual 3D language learning games, Pomy. To verify the effects of our approaches on students' communicative abilities, we have conducted a field study at an elementary school in Korea. The results showed that our CALL approaches can be enjoyable and fruitful activities for students. Although the results of this study bring us a step closer to understanding computer-based education, more studies are needed to consolidate the findings.

  1. 5 CFR 9701.231 - Conversion of positions and employees to the DHS classification system.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Conversion of positions and employees to the DHS classification system. 9701.231 Section 9701.231 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMA...

  2. 5 CFR 9701.373 - Conversion of employees to the DHS pay system.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Conversion of employees to the DHS pay system. 9701.373 Section 9701.373 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT...

  3. Conversational Rate of a Non-Vocal Person with Motor Neurone Disease Using the 'TALK' System.

    Science.gov (United States)

    Todman, J.; Lewins, E.

    1996-01-01

    This study evaluated the use of TALK, a computer-based augmentative and alternative communication (AAC) system, in the social communications of a nonvocal woman with motor neurone disease. She was able to achieve an average conversational rate of 42 words per minute (wpm) using TALK, compared with 2 to 10 wpm with other AAC systems using…

  4. Characterization of solid waste conversion and cogeneration systems

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    The primary objective of the TASE program is to determine the probable consequences to the environment and to public health and safety resulting from widespread implementation of major solar and renewable resource technologies. The specific principal Phase I objective is to determine the levels of residuals most likely to result throughout the complete energy cycle from the utilization of each of the solar and renewable resource technologies. Three basic technologies for recovering energy from M SW are considered in this study. These are: (1) direct combustion using a waterwall incinerator in which the heat from burning refuse is converted to steam by circulating water in steel tubes jacketing the interior of the incinerator; (2) manufacture of a relatively uniform shredded, pulverized or pelleted refuse-derived fuel (RDF) for supplemental firing in a utility boiler; and (3) pyrolysis or destructive distillation of MSW to extract a low-Btu fuel gas. While resource recovery and energy recovery systems can be installed independently, the processes described here include both energy and resource recovery systems as well as necessary pollution control equipment for gaseous emissions. To meet the Phase I objective, LBL staff have characterized the individual application associated with each general technology; calculated operational residuals generated by each application; determined the input capital requirements and, when possible, annual operating input requirements; and have identified the technical and institutional constraints for the widespread implementation of each application. A description is presented of the energy and material development cycle required for the implementation of each technology. The capital requirements are compiled and presented in a SEAS system format.

  5. THE PAYG VARIANT VERSUS THE FULLY FUNDED VARIANT IN CONFIGURING AN EFFECTIVE PENSION SYSTEM

    Directory of Open Access Journals (Sweden)

    CIPRIAN PANZARU

    2011-04-01

    Full Text Available The actual situation is characterized by a major transformation of economical structures, such as: the decrease of population, the increase of participation rate of younger people in higher education and most important, massive retirements and migration. These aspects have generated a drastic decrease in labor force and have brought imbalance in Romanian pension system. Now, the Romanian system of pensions based the principle of social solidarity (support by those who have an income now for the people who worked in the past known as a „pay as you go” system – PAYG has demonstrated its limits, especially due to the current demographic context. This system is an un-funded one not based on economizing. On the other side, private pension systems, either obligatory or optional, are fully funded and based on process of economizing. PAYG pension systems are more vulnerable to demographic changes than pension systems base on accumulation and capitalization. This paper presents, in comparative approach, these two pension systems and corroborating them with present sociodemographic situation try to disclose whichever is more viable in ensuring sustainability of pension system from Romania.

  6. HVDC transmission power conversion applications in power systems

    CERN Document Server

    Kim, Chan-Ki; Jang, Gil-Soo; Lim, Seong-Joo; Lee, Seok-Jin

    2009-01-01

    HVDC is a critical solution to several major problems encountered when trying to maintain systemic links and quality in large-scale renewable energy environments. HDVC can resolve a number of issues, including voltage stability of AC power networks, reducing fault current, and optimal management of electric power, ensuring the technology will play an increasingly important role in the electric power industry. To address the pressing need for an up-to-date and comprehensive treatment of the subject, Kim, Sood, Jang, Lim and Lee have collaborated to produce this key text and reference.  Combin

  7. Application of Circuit Model for Photovoltaic Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Natarajan Pandiarajan

    2012-01-01

    Full Text Available Circuit model of photovoltaic (PV module is presented in this paper that can be used as a common platform by material scientists and power electronic circuit designers to develop better PV power plant. Detailed modeling procedure for the circuit model with numerical dimensions is presented using power system blockset of MATLAB/Simulink. The developed model is integrated with DC-DC boost converter with closed-loop control of maximum power point tracking (MPPT algorithm. Simulation results are validated with the experimental setup.

  8. Paying for pensions: An international comparison of administrative charges in funded retirement-income systems

    OpenAIRE

    Whitehouse, Edward

    2000-01-01

    High charges for personal pensions were one factor in the personal pensions mis-selling debacle in the United Kingdom. They continued to arouse concern among politicians and commentators. The Labour government, with its new flagship ‘stakeholder’ pension, chose to regulate both the structure of charges and their level. This paper assesses the international experience of charges in funded retirement-income systems, drawing on evidence from fourteen countries with very diverse policies. Measuri...

  9. A comparison and conversion table of 'the House-Brackmann facial nerve grading system' and 'the Yanagihara grading system'.

    Science.gov (United States)

    Satoh, Y; Kanzaki, J; Yoshihara, S

    2000-07-01

    A comparison between the House-Brackmann facial nerve grading system (the HB-system) and the Yanagihara grading system (the Y-system) was studied with 199 evaluations of 62 cases of postoperative unilateral acoustic neuroma. In the beginning, an original draft of the conversion table was formulated according to the 199 evaluations, in which, 0-6, 8-14, 16-20, 22-28, 30-38, and 40 points in the Y-system were matched with grade VI, V, IV, III, II, and I in the HB-system respectively. The result of the present study for prediction of sequelae showed that it was not necessary to consider the sequelae in a conversion table. And more, the study of an inter-observer variation showed that the lower and upper limits of the scores in the Y-system may shift within about a 2-point range in the draft table. From these aspects, a newly revised conversion table was proposed as a revised conversion table, in which, 0-6, 8-14, 16-22, 24-30, 32-38, and 40 points in the Y-system were matched with grade VI, V, IV, III, II, and I in the HB-system. This revised conversion table is much easier to remember for clinical use, because the score of the lower limit of each grade is simply in multiples of 8, that is, 0, 8, 16, 24, 32 and 40.

  10. Feedstock and Conversion Supply System Design and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mohammad, R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cafferty, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kenney, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Searcy, E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hansen, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    The success of the earlier logistic pathway designs (Biochemical and Thermochemical) from a feedstock perspective was that it demonstrated that through proper equipment selection and best management practices, conventional supply systems (referred to in this report as “conventional designs,” or specifically the 2012 Conventional Design) can be successfully implemented to address dry matter loss, quality issues, and enable feedstock cost reductions that help to reduce feedstock risk of variable supply and quality and enable industry to commercialize biomass feedstock supply chains. The caveat of this success is that conventional designs depend on high density, low-cost biomass with no disruption from incremental weather. In this respect, the success of conventional designs is tied to specific, highly productive regions such as the southeastern U.S. which has traditionally supported numerous pulp and paper industries or the Midwest U.S for corn stover.

  11. MHD conversion of solar energy. [space electric power system

    Science.gov (United States)

    Lau, C. V.; Decher, R.

    1978-01-01

    Low temperature plasmas wherein an alkali metal vapor is a component are uniquely suited to simultaneously absorb solar radiation by coupling to the resonance lines and produce electrical power by the MHD interaction. This work is an examination of the possibility of developing space power systems which take advantage of concentrated solar power to produce electricity. It is shown that efficient cycles in which expansion work takes place at nearly constant top cycle temperature can be devised. The power density of the solar MHD generator is lower than that of conventional MHD generators because of the relatively high seed concentration required for radiation absorption and the lower flow velocity permitted to avoid total pressure losses due to heating.

  12. Hydrokinetic energy conversion systems: A technology status review

    Energy Technology Data Exchange (ETDEWEB)

    Gueney, M.S. [Machinery Programm of Machinery of Undergraduate School, Giresun University, 28100 Giresun (Turkey); Kaygusuz, K. [Department of Chemistry, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2010-12-15

    The growing demand for electrical energy is one of the most important subjects today. Decreasing amount and environmental effect of fossil fuels does not seem to surmount this challenge. Renewable energies give a good perspective to be an alternative to fossil and nuclear-fueled power plants, in order to meet growing demand for electrical energy. Hydropower is well known in this category. Hydrokinetic energy technologies are relatively new than other hydropower systems. In this work has been investigated these kinds of hydrokinetic energy, and given some detailed information about current base of hydrokinetic. It has tried to give some knowledge in order to familiarize with the hydrokinetic turbine and generator. The selection information of a suitable turbine has been mentioned. (author)

  13. Design of a simple, effective and low cost micro wind energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Luna, Massimiliano; Pucci, Marcello; Vitale, Gianpaolo

    2011-07-01

    The installation of micro-wind energy conversion systems (MWECS) depends on the system's performance and cost. The aim of this study is to present a MWECS developed for low power applications connected to the grid. The system containing a micro-wind turbine, a PMSM machine, a diode bridge, a boost DC/DC converter and a grid connected single phase inverter was developed and then tested. The results showed a good performance of the system, it can deliver up to twice as much energy as a conventional system in the same conditions. This technology is also cheaper and simpler than its concurrents. This study developed a simple effective and low cost micro wind energy conversion system.

  14. Energy Conversion Loop: A Testbed for Nuclear Hybrid Energy Systems Use in Biomass Pyrolysis

    Science.gov (United States)

    Verner, Kelley M.

    Nuclear hybrid energy systems are a possible solution for contemporary energy challenges. Nuclear energy produces electricity without greenhouse gas emissions. However, nuclear power production is not as flexible as electrical grids demand and renewables create highly variable electricity. Nuclear hybrid energy systems are able to address both of these problems. Wasted heat can be used in processes such as desalination, hydrogen production, or biofuel production. This research explores the possible uses of nuclear process heat in bio-oil production via biomass pyrolysis. The energy conversion loop is a testbed designed and built to mimic the heat from a nuclear reactor. Small scale biomass pyrolysis experiments were performed and compared to results from the energy conversion loop tests to determine future pyrolysis experimentation with the energy conversion loop. Further improvements must be made to the energy conversion loop before more complex experiments may be performed. The current conditions produced by the energy conversion loop are not conducive for current biomass pyrolysis experimentation.tion.

  15. Coordinated Operation of the Electricity and Natural Gas Systems with Bi-directional Energy Conversion

    DEFF Research Database (Denmark)

    Zeng, Qing; Zhang, Baohua; Fang, Jiakun

    2017-01-01

    A coordinated operation of the natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables. This work focuses on the unified optimal operation of the integrated natural gas and electricity system considering the network...

  16. Loss comparison of different nine-switch and twelve-switch energy conversion systems

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Loh, Poh Chiang; Qin, Zian

    2014-01-01

    with an answer only available after performing a thorough analysis. For that, it is the intention now to compare the nine-switch and twelve-switch converters when they are used in ac-ac, ac-dc, dc-ac or dc-dc energy conversion systems. Their losses will be compared to identify when the nine-switch converter...

  17. Understanding Power Electronics and Electrical Machines in Multidisciplinary Wind Energy Conversion System Courses

    Science.gov (United States)

    Duran, M. J.; Barrero, F.; Pozo-Ruz, A.; Guzman, F.; Fernandez, J.; Guzman, H.

    2013-01-01

    Wind energy conversion systems (WECS) nowadays offer an extremely wide range of topologies, including various different types of electrical generators and power converters. Wind energy is also an application of great interest to students and with a huge potential for engineering employment. Making WECS the main center of interest when teaching…

  18. Dynamic modelling and robust control of a wind energy conversion system

    NARCIS (Netherlands)

    Steinbuch, M.

    1989-01-01

    The application of wind energy conversion systems for the production of electrical energy requires a cheap and reliable operation. Especially at high wind velocities fluctuations from the wind field result in large mechanical loads of the wind turbine. Also fluctuations in the grid voltage may yield

  19. Robust Sliding Mode Control of Permanent Magnet Synchronous Generator-Based Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Guangping Zhuo

    2016-12-01

    Full Text Available The subject of this paper pertains to sliding mode control and its application in nonlinear electrical power systems as seen in wind energy conversion systems. Due to the robustness in dealing with unmodeled system dynamics, sliding mode control has been widely used in electrical power system applications. This paper presents first and high order sliding mode control schemes for permanent magnet synchronous generator-based wind energy conversion systems. The application of these methods for control using dynamic models of the d-axis and q-axis currents, as well as those of the high speed shaft rotational speed show a high level of efficiency in power extraction from a varying wind resource. Computer simulation results have shown the efficacy of the proposed sliding mode control approaches.

  20. Collaborative role construction in a conversation with dementia: an application of systemic functional linguistics.

    Science.gov (United States)

    Müller, Nicole; Wilson, Brent T

    2008-01-01

    This study applies the tools provided by Systemic Functional Linguistics (SFL) to the description of patterns in a conversation between a person with dementia and a person without. It shows how, in the presence of, on the one hand, considerable communicative and cognitive deficits, and on the other, a collaborative interlocutor, a person with dementia succeeds in leading and sustaining a lengthy conversation, and of constructing for himself a positive role in the interaction, namely that of the elder advising a much younger man.

  1. Preservice Mathematics Teachers' Solutions to Problems: Conversions within the Metric System

    Directory of Open Access Journals (Sweden)

    Jean E. Hallagan

    2013-10-01

    Full Text Available This paper reports on the results of a preliminary investigation to determine if preservice mathematics teachers solve conversion problems within the metric system in multiple ways. Here, four metric conversion problems of escalating difficulty were administered within a mathematics methods course at a comprehensive state university in the Northeastern United States. Results show that preservice teachers solved the problems in the same way that they were taught in high school, and that in high school they were only taught one way.

  2. Greenhouse Gas Conversion by Homogeneous Salen Catalyst Systems under Very Mild Reaction Condition

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Hyungsock; Song, Sanghoon; Ahn, Sunghyun; Kim, Taesoon; Kim, Beomsik; Chang, Taesun [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of)

    2013-08-15

    Homogeneous salen catalyt systems were investigated for the conversion of greenhouse gas into cyclic carbonate under room temperature and atmospheric pressure. Salen complexes were more active than salophen complexes. Neither electron withdrawing nor donating group showed lower conversion efficiency. Co-catalysts such as moisture or ammonium salt increased the conversion efficiency dramatically. These results have potential to decrease carbon dioxide emitted from fossil fuel combustions under mild condition. One of the main scientific challenges in the 21st century is the global warming due to the increasing level of carbon dioxide. The consumption of fossil fuels is continue to increase with emitting substantial amount of green house gas. The solution currently considered is capturing and storing of carbon dioxide which compressing carbon dioxide and then storing it into oil wells or under the ocean. The other solution include converting the carbon dioxide into useful chemicals with significant commercial demand, but low chemical reactivity of carbon dioxide restricts the chemical reactions.

  3. Experimental self-etching HEMA-free adhesive systems: cytotoxicity and degree of conversion.

    Science.gov (United States)

    Barbosa, Marília Oliveira; de Carvalho, Rodrigo Varella; Demarco, Flávio Fernando; Ogliari, Fabrício Aulo; Zanchi, Cesar Henrique; Piva, Evandro; da Silva, Adriana Fernandes

    2015-01-01

    The aim of this study was to evaluate the effect of replacing 2-hydroxyethyl methacrylate (HEMA) by methacrylate surfactant monomers on the cytotoxicity and degree of conversion of two-step self-etching dentin adhesive systems. Five HEMA-free adhesive systems were tested: Bis-EMA 10, Bis-EMA 30, PEG400, PEG400UDMA, PEG1000, and a HEMA group was used as positive control. The cytotoxicity of the experimental primers, with different monomer concentrations (2 or 20 wt%), and bond resins, containing 25 wt% surfactant, was assessed using murine fibroblast cell line 3T3 and the tetrazolium assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)). The degree of conversion of the bond resins was analyzed using Fourier transform infrared spectroscopy. The data were submitted to statistical analysis using level of significance set at P cytotoxic than HEMA. With regard to the eluate from bond resin, the data showed that the groups BIS-EMA 10, BIS-EMA 30 and PEG400UDMA were less cytotoxic than HEMA. No statistically significant difference was found among degrees of conversion of the experimental groups and HEMA. PEG 1000, BIS-EMA 10 and 30 monomers showed the biological potential for use in new adhesive system formulations since they showed lower cytotoxicity and similar degree of conversion when compared with the HEMA-containing group.

  4. Critical interactions between Global Fund-supported programmes and health systems: a case study in Lao People's Democratic Republic.

    Science.gov (United States)

    Mounier-Jack, Sandra; Rudge, James W; Phetsouvanh, Rattanaxay; Chanthapadith, Chansouk; Coker, Richard

    2010-11-01

    In Lao PDR, investment by the Global Fund to Fight AIDS, Tuberculosis and Malaria has played an important role in scaling up the response to HIV and tuberculosis (TB). As part of a series of case studies on how Global Fund-supported programmes interact with national health systems, we assessed the nature and extent of integration of the Global Fund portfolios within the national HIV and TB programmes, the integration of the HIV and TB programmes within the general health system, and system-wide effects of Global Fund support in Lao PDR. The study relied on a literature review and 35 interviews with key stakeholders using the Systemic Rapid Assessment Toolkit and thematic analysis. In Lao PDR, the HIV and TB programmes remain vertical and mostly weakly integrated with the general health system. However, Global Fund investments have extended the network of facilities delivering care at local level, resulting in greater integration with primary care and improved access for patients, particularly for TB. For HIV, as the prevalence remains low, services primarily target high-risk groups in urban areas. Less integrated functions include procurement and drug supply, and monitoring and evaluation. HIV and TB programmes are only starting to coordinate with each other. Global Fund-supported activities are generally integrated within the national disease programmes, except for monitoring and evaluation. Synergies of Global Fund support with the health system include improved access to services, institutional strengthening and capacity building, improved family planning (with wider condom distribution through HIV/AIDS social marketing programmes), and the delivery of add-on interventions, such as vaccinations and health education, alongside Global Fund-supported interventions at community level. Unintended consequences concern the lack of alignment between national stated priorities (maternal and child health) and the strong focus of external partners, such as the Global Fund

  5. Plasma heating due to X-B mode conversion in a cylindrical ECR plasma system

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, V.K.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat (India)

    2004-07-01

    Extra Ordinary (X) mode conversion to Bernstein wave near Upper Hybrid Resonance (UHR) layer plays an important role in plasma heating through cyclotron resonance. Wave generation at UHR and parametric decay at high power has been observed during Electron Cyclotron Resonance (ECR) heating experiments in toroidal magnetic fusion devices. A small linear system with ECR and UHR layer within the system has been used to conduct experiments on X-B conversion and parametric decay process as a function of system parameters. Direct probing in situ is conducted and plasma heating is evidenced by soft x-ray emission measurement. Experiments are performed with hydrogen plasma produced with 160-800 W microwave power at 2.45 GHz of operating frequency at 10{sup -3} mbar pressure. The axial magnetic field required for ECR is such that the resonant surface (B = 875 G) is situated at the geometrical axis of the plasma system. Experimental results will be presented in the paper. (authors)

  6. Megawatt Class Nuclear Space Power Systems (MCNSPS) conceptual design and evaluation report. Volume 3, technologies 2: Power conversion

    Science.gov (United States)

    Wetch, J. R.

    1988-01-01

    The major power conversion concepts considered for the Megawatt Class Nuclear Space Power System (MCNSPS) are discussed. These concepts include: (1) Rankine alkali-metal-vapor turbine alternators; (2) in-core thermionic conversion; (3) Brayton gas turbine alternators; and (4) free piston Stirling engine linear alternators. Considerations important to the coupling of these four conversion alternatives to an appropriate nuclear reactor heat source are examined along with the comparative performance characteristics of the combined systems meeting MCNSPS requirements.

  7. Autonomous wind energy conversion system with a simple controller for maximum-power transfer

    Energy Technology Data Exchange (ETDEWEB)

    Ermis, M.; Ertan, H.B. (Middle East Technical Univ., Ankara (Turkey). Dept. of Electrical and Electronic Engineering); Akpinar, E. (New Orleans Univ., LA (United States). Dept. of Electrical Engineering); Uelguet, F. (Aselsan Military Electronic Ind. Inc., Ankara (Turkey))

    1992-09-01

    The paper describes a small autonomous wind energy conversion system. A simple, closed-loop control system assures maximum-power transfer by the aid of a lookup table which relates the electrical power output of the system to the shaft speed. A directly-coupled, wound-rotating field synchronous generator is used for energy conversion. The generator speed in this system is variable while the terminal voltage is substantially constant. The terminal voltage is kept under control by varying the field current to meet various load and battery conditions. In the paper a new criterion for determining optimum dimensions of a generator for wind energy conversion system applications is introduced. This criterion envisages a maximisation of the energy output for the chosen wind regime while keeping the generator cost at a minimum. To obtain the optimum solution of the cost minimisation problem, the constrained optimisation problem is first converted to the unconstrained form by using the external penalty approach and then solved using the Devidon-Fletcher-Powel method. Results of the optimisation are presented and evaluated. (author)

  8. Research and Technology Activities Supporting Closed-Brayton-Cycle Power Conversion System Development

    Science.gov (United States)

    Barrett, Michael J.

    2004-01-01

    The elements of Brayton technology development emphasize power conversion system risk mitigation. Risk mitigation is achieved by demonstrating system integration feasibility, subsystem/component life capability (particularly in the context of material creep) and overall spacecraft mass reduction. Closed-Brayton-cycle (CBC) power conversion technology is viewed as relatively mature. At the 2-kWe power level, a CBC conversion system Technology Readiness Level (TRL) of six (6) was achieved during the Solar Dynamic Ground Test Demonstration (SD-GTD) in 1998. A TRL 5 was demonstrated for 10 kWe-class CBC components during the development of the Brayton Rotating Unit (BRU) from 1968 to 1976. Components currently in terrestrial (open cycle) Brayton machines represent TRL 4 for similar uses in 100 kWe-class CBC space systems. Because of the baseline component and subsystem technology maturity, much of the Brayton technology task is focused on issues related to systems integration. A brief description of ongoing technology activities is given.

  9. Evaluation testing of a closed Brayton-cycle electrical-power-conversion system.

    Science.gov (United States)

    Redding, T. E.; Mcgee, J. M.; Luksa, N. C.

    1972-01-01

    Description of the design and testing of a recuperated, closed Brayton-cycle, electrical power conversion system designated the Brayton Cycle Demonstrator (BCD). The system uses electrical heaters as a heat source, argon as the cycle working fluid, and gas-lubricated foil-type bearings. Objectives of the test program include (1) evaluation of the overall system performance characteristics and influences on spacecraft integration, (2) familiarization of personnel with operational methods, and (3) determination of system flexibility by operating at a number of off-design conditions. Results obtained to date are discussed.

  10. Electric utility application of wind energy conversion systems on the island of Oahu

    Energy Technology Data Exchange (ETDEWEB)

    Lindley, C.A.; Melton, W.C.

    1979-02-23

    This wind energy application study was performed by The Aerospace Corporation for the Wind Systems Branch of the Department of Energy. The objective was to identify integration problems for a Wind Energy Conversion System (WECS) placed into an existing conventional utility system. The integration problems included environmental, institutional and technical aspects as well as economic matters, but the emphasis was on the economics of wind energy. The Hawaiian Electric Company utility system on the island of Oahu was selected for the study because of the very real potential for wind energy on that island, and because of the simplicity afforded in analyzing that isolated utility.

  11. Leveraging Federal Funding for Longitudinal Data Systems: A Roadmap for States. Fiscal Year 2011

    Science.gov (United States)

    Data Quality Campaign, 2011

    2011-01-01

    States should use this roadmap to identify and leverage federal funding sources for data-related activities. This roadmap presents such opportunities for FY 2011, and provides guidance on some of the ways the funds may be used.

  12. A Family Systems Nursing Approach for Families Following a Stroke: Family Health Conversations.

    Science.gov (United States)

    Östlund, Ulrika; Bäckström, Britt; Saveman, Britt-Inger; Lindh, Viveca; Sundin, Karin

    2016-05-01

    Stroke in midlife is a life altering, challenging experience for the whole family thereby necessitating a family approach to intervention. The aim of this study was to describe the experiences of 17 family members living in Sweden, including seven adult stroke patients (six males; one female) under the age of 65 who participated in a series of three nurse-led family conversations that were offered in each family's home. These Family Health Conversations (FamHC) were guided by the conceptual lens of Family System Nursing. Individual, semi-structured, evaluative interviews conducted with each participant one month after the FamHC were analyzed by qualitative content analysis. The FamHC were described by family members as a unique conversation that they had not previously experienced in health care contexts. Family members described possibilities for relational sharing and meaningful conversations as well as changes in family functioning that support the suitability of FamHC for family stroke care. © The Author(s) 2016.

  13. A space-based combined thermophotovoltaic electric generator and gas laser solar energy conversion system

    Science.gov (United States)

    Yesil, Oktay

    1989-01-01

    This paper describes a spaceborne energy conversion system consisting of a thermophotovoltaic electric generator and a gas laser. As a power source for the converson, the system utilizes an intermediate blackbody cavity heated to a temperature of 2000-2400 K by concentrated solar radiation. A double-layer solar cell of GaAs and Si forms a cylindrical surface concentric to this blackbody cavity, receiving the blackbody radiation and converting it into electricity with cell conversion efficiency of 50 percent or more. If the blackbody cavity encloses a laser medium, the blackbody radiation can also be used to simultaneously pump a lasing gas. The feasibility of blackbody optical pumping at 4.3 microns in a CO2-He gas mixture was experimentally demonstrated.

  14. Two Level Versus Matrix Converters Performance in Wind Energy Conversion Systems Employing DFIG

    Science.gov (United States)

    Reddy, Gongati Pandu Ranga; Kumar, M. Vijaya

    2017-10-01

    Wind power capacity has received enormous growth during past decades. With substantial development of wind power, it is expected to provide a fifth of world's electricity by the end of 2030. In wind energy conversion system, the power electronic converters play an important role. This paper presents the two level and matrix converters performance in wind energy conversion system employing Doubly Fed Induction Generator (DFIG). The DFIG is a wound rotor induction generator. Because of the advantages of the DFIG over other generators it is being used for most of the wind applications. This paper also discusses control of converters using the space vector pulse width modulation technique. The MATLAB/SIMULINK ® software is used to study the performance of the converters.

  15. Two Level Versus Matrix Converters Performance in Wind Energy Conversion Systems Employing DFIG

    Science.gov (United States)

    Reddy, Gongati Pandu Ranga; Kumar, M. Vijaya

    2017-05-01

    Wind power capacity has received enormous growth during past decades. With substantial development of wind power, it is expected to provide a fifth of world's electricity by the end of 2030. In wind energy conversion system, the power electronic converters play an important role. This paper presents the two level and matrix converters performance in wind energy conversion system employing Doubly Fed Induction Generator (DFIG). The DFIG is a wound rotor induction generator. Because of the advantages of the DFIG over other generators it is being used for most of the wind applications. This paper also discusses control of converters using the space vector pulse width modulation technique. The MATLAB/SIMULINK ® software is used to study the performance of the converters.

  16. An adaptive feedback linearization strategy for variable speed wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, F.; Puleston, P.F.; Battaiotto, P.E.; Mantz, R.J. [Universidad Nacional de La Plata, Depto. de Electrotecnia, La Plata (Argentina)

    2000-07-01

    This paper presents a control strategy based on adaptive feedback linearization intended for variable speed grid-connected wind energy conversion systems (WECS). The proposed adaptive control law accomplishes energy capture maximization by tracking the wind speed fluctuations. In addition, it linearizes the system even in the presence of turbine model uncertainties, allowing the closed-loop dynamic behaviour to be determined by a simple tuning of the controller parameters. Particularly, the attention is focused on WECS with slip power recovery, which use a power conversion stage as a rotor-controlled double-output induction generator. However, the concepts behind the proposed control strategy are general and can be easily extended to other WECS configurations. (Author)

  17. Legal-institutional arrangements facilitating offshore wind energy conversion systems (WECS) utilization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mayo, L.H.

    1977-09-01

    Concern for the continuing sufficiency of energy supplies in the U.S. has tended to direct increasing attention to unconventional sources of supply, including wind energy. Some of the more striking proposals for the utilization of wind energy relate to offshore configurations. The legal-institutional arrangements for facilitating the utilization of offshore wind energy conversion systems (WECS) are examined by positioning three program alternatives and analyzing the institutional support required for the implementation of each.

  18. Generators for Wind Energy Conversion Systems: State of the Art and Coming Attractions

    OpenAIRE

    Y. Amirat*; M. E. H. Benbouzid; B. Bensaker; R. Wamkeue

    2007-01-01

    Wind Energy Conversion Systems (WECS) have become a focal point in the research of renewable energy sources. This paper provides then a comparative study of past and present generator technologies used in WECS. This study is based on an exhaustive review of the state of the art and on an effective comparison of the performances of the four main topologies that are permanent magnet generators, synchronous generators, induction generators and doubly-fed induction generators. The different gener...

  19. Novel Control for Voltage Boosted Matrix Converter based Wind Energy Conversion System with Practicality

    Science.gov (United States)

    Kumar, Vinod; Joshi, Raghuveer Raj; Yadav, Dinesh Kumar; Garg, Rahul Kumar

    2017-04-01

    This paper presents the implementation and investigation of novel voltage boosted matrix converter (MC) based permanent magnet wind energy conversion system (WECS). In this paper, on-line tuned adaptive fuzzy control algorithm cooperated with reversed MC is proposed to yield maximum energy. The control system is implemented on a dSPACE DS1104 real time board. Feasibility of the proposed system has been experimentally verified using a laboratory 1.2 kW prototype of WECS under steady-state and dynamic conditions.

  20. Geo-spatial multi-criteria analysis for wave energy conversion system deployment

    Energy Technology Data Exchange (ETDEWEB)

    Nobre, Ana; Pacheco, Miguel [Data Centre, Instituto Hidrografico, Portuguese Navy, Rua das Trinas 49, 1249-093 Lisboa (Portugal); Jorge, Raquel; Lopes, M.F.P.; Gato, L.M.C. [IDMEC, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais 1, 1049-001, Lisboa (Portugal)

    2009-01-15

    The growing requirements for renewable energy production lead to the development of a new series of systems, including wave energy conversion systems. Due to their sensitivity and the impact of the aggressive marine environment, the selection of the most adequate location for these systems is a major and very important task. Several factors, such as technological limitations, environmental conditions, administrative and logistic conditions, have to be taken into account in order to support the decision for best location. This paper describes a geo-spatial multi-criteria analysis methodology, based on geographic information systems technology, for identification of the best location to deploy a wave energy farm. This methodology is not conversion system dependent and therefore can be easily customized for different systems and implementation conditions. Selection factors can include, for example, ocean depth, sea bottom type, existing underwater cables, marine protected areas, ports location, shoreline, power grid location, military exercise areas, climatology of wave significant height, period and power. A case study demonstrating this methodology is presented, for an area offshore the Portuguese southwest coast. The system output allows a clear differential identification of the best spots for implementing a wave energy farm. It is not just a simple Boolean result showing valid and invalid locations, but a layer with a valued suitability for farm deployment. (author)

  1. Solid Waste Information and Tracking System Client Server Conversion Project Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    GLASSCOCK, J.A.

    2000-02-10

    The Project Management Plan governing the conversion of SWITS to a client-server architecture. The PMP describes the background, planning and management of the SWITS conversion. Requirements and specification documentation needed for the SWITS conversion

  2. Ocean Current Energy Conversion System in Wallacea Region Using Variable Speed Control Approach

    Directory of Open Access Journals (Sweden)

    Aditya Sukma Nugraha

    2012-03-01

    Full Text Available Ocean Current Energy Conversion System (OCECS is a promising green energy resource in this globe. The Thermohaline circulation data indicates that the Wallacea region has the potential of ocean current energy resources. This paper is aimed to propose research and development of OCECSs to be implemented in the Wallacea region. Firstly, four types of green energy conversion systems extracted from ocean are reviewed. Their advantages and disadvantages are discussed. Secondly, the potential of OCECS in the Wallacea region is described. Third, many types of turbines used for OCECS are reviewed and the turbine type for OCECS is selected to be implemented in the Wallacea region. Fourth, control strategy is proposed.From the work reported in this paper it is concluded that it is appropriate to implement OCECSs using axial flow water turbines in the Wallacea region, and that to maximize energy conversion variable speed control approach is selected together with control of mechanism to move the turbine vertically as well as to rotate the turbine in yaw direction. 

  3. Control of modular multilevel converters for grid integration of full-scale wind energy conversion systems

    Science.gov (United States)

    Debnath, Suman

    The growing demand for wind power generation has pushed the capacity of wind turbines towards MW power levels. Higher capacity of the wind turbines necessitates operation of the generators and power electronic conversion systems at higher voltage/power levels. The power electronic conversion system of a wind energy conversion system (WECS) needs to meet the stringent requirements in terms of reliability, efficiency, scalability and ease of maintenance, power quality, and dv/dt stress on the generator/transformer. Although the multilevel converters including the neutral point clamped (NPC) converter and the active NPC converter meet most of the requirements, they fall short in reliability and scalability. Motivated by modularity/scalability feature of the modular multilevel converter (MMC), this research is to enable the MMC to meet all of the stringent requirements of the WECS by addressing their unique control challenges. This research presents systematic modeling and control of the MMC to enable it to be a potential converter topology for grid integration of full-scale WECSs. Based on the developed models, appropriate control systems for control of circulating current and capacitor voltages under fixed- and variable-frequency operations are proposed. Using the developed MMC models, a gradient-based cosimulation algorithm to optimize the gains of the developed control systems, is proposed. Performance/effectiveness of the developed models and the proposed control systems for the back-to-back MMC-based WECS are evaluated/verified based on simulations studies in the PSCAD/EMTDC software environment and experimental case studies on a laboratory-scale hardware prototype.

  4. Construction of biomimetic smart nanochannels with polymer membranes and application in energy conversion systems.

    Science.gov (United States)

    Wen, Liping; Tian, Ye; Ma, Jie; Zhai, Jin; Jiang, Lei

    2012-03-28

    Learning from nature has inspired the creation of intelligent devices to meet the increasing needs of the advanced community and also to better understand how to imitate biology. As one of biomimetic nanodevices, nanochannels or nanopores aroused particular interest because of their potential applications in nanofluidic devices, biosensing, filtration, and energy conversions. In this review we have summarized some recent results mainly focused on the design, construction and application in energy conversion systems. Like biological nanochannels, the prepared smart artificial nanochannels fabricated by ion track-etched polymer membranes and smart molecules show a great potential in the field of bioengineering and biotechnology. And these applications can not only help people to know and understand the living processes in nature, but can also inspire scientists to study and develop novel nanodevices with better performance for the mankind.

  5. Smart Bioinspired Nanochannels and their Applications in Energy-Conversion Systems.

    Science.gov (United States)

    Li, Ruirui; Fan, Xia; Liu, Zhaoyue; Zhai, Jin

    2017-12-01

    Smart bioinspired nanochannels exhibiting ion-transport properties similar to biological ion channels have attracted extensive attention. Like ion channels in nature, smart bioinspired nanochannels can respond to various stimuli, which lays a solid foundation for mass transport and energy conversion. Fundamental research into smart bioinspired nanochannels not only furthers understanding of life processes in living bodies, but also inspires researchers to construct smart nanodevices to meet the increasing demand for the use of renewable resources. Here, a brief summary of recent research progress regarding the design and preparation of smart bioinspired nanochannels is presented. Moreover, representative applications of smart bioinspired nanochannels in energy-conversion systems are also summarized. Finally, an outlook for future challenges in this field is given. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Making sense of the emerging conversation in evaluation about systems thinking and complexity science.

    Science.gov (United States)

    Gates, Emily F

    2016-12-01

    In the last twenty years, a conversation has emerged in the evaluation field about the potential of systems thinking and complexity science (STCS) to transform the practice of evaluating social interventions. Documenting and interpreting this conversation are necessary to advance our understanding of the significance of using STCS in planning, implementing, and evaluating social interventions. Guided by a generic framework for evaluation practice, this paper reports on an inter-disciplinary literature review and argues that STCS raises some new ways of thinking about and carrying out the following six activities: 1) supporting social problem solving; 2) framing interventions and contexts; 3) selecting and using methods; 4) engaging in valuing; 5) producing and justifying knowledge; and 6) facilitating use. Following a discussion of these issues, future directions for research and practice are suggested. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Experimental and Analytical Performance of a Dual Brayton Power Conversion System

    Science.gov (United States)

    Lavelle, Thomas A.; Hervol, David S.; Briggs, Maxwell; Owen, A. Karl

    2009-01-01

    The interactions between two closed Brayton cycle (CBC) power conversion units (PCU) which share a common gas inventory and heat source have been studied experimentally using the Dual Brayton Power Conversion System (DBPCS) and analytically using the Closed- Cycle System Simulation (CCSS) computer code. Selected operating modes include steady-state operation at equal and unequal shaft speeds and various start-up scenarios. Equal shaft speed steady-state tests were conducted for heater exit temperatures of 840 to 950 K and speeds of 50 to 90 krpm, providing a system performance map. Unequal shaft speed steady-state testing over the same operating conditions shows that the power produced by each Brayton is sensitive to the operating conditions of the other due to redistribution of gas inventory. Startup scenarios show that starting the engines one at a time can dramatically reduce the required motoring energy. Although the DBPCS is not considered a flight-like system, these insights, as well as the operational experience gained from operating and modeling this system provide valuable information for the future development of Brayton systems.

  8. Progress of conversion system from CAD data to MCNP geometry data in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Sato, S., E-mail: sato.satoshi92@jaea.go.jp [Japan Atomic Energy Agency, 2-4 Shirakatashirane, Tokai-Mura, Ibaraki-ken 319-1195 (Japan); Nashif, H.; Masuda, F.; Morota, H.; Iida, H. [MHI Nuclear Engineering Company Ltd., Minatoku, Tokyo 108-0075 (Japan); Konno, C. [Japan Atomic Energy Agency, 2-4 Shirakatashirane, Tokai-Mura, Ibaraki-ken 319-1195 (Japan)

    2010-12-15

    Automatic conversion systems from CAD data to MCNP geometry input data have been developed to convert the CAD data of the fusion reactor with very complicated structure. So far, two conversion systems (GEOMIT-1 and ARCMCP) have been developed and the third system (GEOMIT-2) is under developing. The void data can be created in these systems. GEOMIT-1 was developed in 2007, but a lot of manual shape splitting work for the CAD data was required to convert the complicated geometry. ARCMCP was developed in 2008. The algorithm has been drastically improved on automatic creation of ambiguous surface in ARCMCP, but it still required a little manual shape splitting work. The latest system, GEOMIT-2, does not require additional commercial software packages, though the previous systems require them. It also has functions of the CAD data healing and the automatic shape splitting. Geometrical errors of CAD data can be automatically revised by the healing function, and complicated geometries can be automatically split into simple geometries by the shape splitting function. Any manual works for CAD data are not required in GEOMIT-2. GEOMIT-2 is very useful for nuclear analyses of fusion reactors.

  9. Urban Waste Conversion Systems. IGT Project 61030 final report, October 1, 1978-March 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Cowen, D.S.; Daniels, E.J.; Novil, M.

    1980-02-01

    The purpose of this study was to assess the market potential of the various systems available, or under development, for converting urban wastes into synthetic gas or liquids. The primary data base for this assessment is a survey which IGT has sent out to experts in this field. The experts were asked to evaluate various conversion systems by assigning point totals to an evaluation matrix. They were also asked to summarize their work in urban waste conversion, to list critical paths which represent obstacles to be surmounted by R and D, and to assess the effect of those obstacles on the market potential of that process. Critical areas for R and D work focus on materials handling and separation techniques, and protection of equipment from abrasive, caustic, or corrosive chemicals in the wastes. Also, prohibitive capital and operating costs in some existing systems must be cited, since investor confidence is eroded by evidence of such experiences. Downtime has been excessive with many systems, stemming from feed problems brought on by the heterogeneous nature of the feedstock. Systems using homogeneous feeds have shown considerably less problems. Perhaps a critical area from a social impact point of view is, can garbage separation be instituted for the home, factory, etc. If so, the chances for waste converison systems to overcome technical problems on the front end are greatly improved, and so is the potential for market penetration.

  10. New Multiphase Hybrid Boost Converter with Wide Conversion Ratio for PV System

    Directory of Open Access Journals (Sweden)

    Ioana-Monica Pop-Calimanu

    2014-01-01

    Full Text Available A new multiphase hybrid boost converter, with wide conversion ratio as a solution for photovoltaic energy system, is presented in this paper. To ensure that all the phases of the converter operate at the same switching frequency we use interleaving topology. The proposed converter can be used as an interface between the PV system and the DC load/inverter. This multiphase converter has the advantage of reduced value and physical size of the input and output capacitor as well as the effort for the inductors. To validate the operation of the converter we provide the analyses and the simulation results of the converter.

  11. Electrical energy conversion system design with single-phase inverter and H5 transformerless topology

    OpenAIRE

    Colina Morles, Eliézer

    2014-01-01

    This paper presents the design of an electrical energy conversion system (EECS) for the use of solar energy and its conditioning for injection of energy to the commercial power grid. A single-phase full-bridge inverter with transformerless H5 topology coupled to a LCL filter is used. The system is identified using an averaged small-signal state space model; while the used cascade control scheme is tuned by pole placement and includes a maximum power disturb-observe tracking type algorithm of ...

  12. The Return-risk Performance of Selected Pension Fund in OECD with Focus on the Czech Pension System

    Directory of Open Access Journals (Sweden)

    Petr Kupčík

    2016-01-01

    Full Text Available This paper focuses on the measuring and comparing investment performance of pension funds in selected European countries. Comparison of the investment performance of pension funds is determined by means of the Sharpe ratio and the Sortino ratio. We used data of nominal appreciation of pension funds from the Czech Republic, Slovakia, Poland, Sweden, Switzerland and the Netherlands in the period 2005−2013. These countries were selected because they have many common features but Sweden, Switzerland and the Netherlands were added to the analysis because we wanted to show the differences between a developed and less developed fully funded system. The last part of this article presents the main causes of the differences in investment performance of pension funds. Conclusions of the paper are focused on a comparison of the results of the Sharpe ratio and the Sortino ratio of pension funds from selected countries and recommendations for the Czech pension system. The article proposes a mechanism for determining the order of the negative Sharpe ratio and the Sortino ratio.

  13. Performance-Based Funding & Online Learning: Maximizing Resources for Student Success

    Science.gov (United States)

    Patrick, Susan; Myers, John; Silverstein, Justin; Brown, Amanda; Watson, John

    2015-01-01

    There is a new conversation taking place in public education on creating systemic incentives through school finance to encourage schools to innovate and be rewarded for positive student outcomes and performance. What if education funding was not based on seat-time, but on rewarding student performance? Performance-based funding is a term that…

  14. Efficiency enhancement of the ocean thermal energy conversion system with a vapor–vapor ejector

    Directory of Open Access Journals (Sweden)

    Ho-Saeng Lee

    2015-03-01

    Full Text Available In this article, 20 kW ocean thermal energy conversion with a vapor–vapor ejector is newly proposed. As a vapor–vapor ejector is installed in the system, the pressure difference between the turbine inlet and outlet increases. Therefore, the amount of the working fluid required for the total turbine work of 20 kW is less than when no vapor–vapor ejector is installed. Therefore, installing a vapor–vapor ejector in the system decreases the evaporation capacity and the pump work. The performance analysis considered the outlet pressure of the high-stage turbine, the mass flow ratio of the working fluid at the outlet of a separator just after the high-stage turbine, and the nozzle diameters of the vapor–vapor ejector. As the outlet pressure of high-stage turbine becomes lower, the turbine gross power of high-stage turbine and system efficiency increase although lower outlet pressure of high-stage turbine results in lower ejector performance. Similarly, in terms of mass flow ratio, the highest system efficiency was shown at mass flow ratio of 0.4 at the outlet of a separator just after the high-stage turbine. On the other hand, the performance of the ejector at mass flow ratio of 0.5 at the outlet of a separator was largest. When the nozzle diameters of the vapor–vapor ejector are properly designed, the vapor–vapor ejector shows the highest performance. After the optimization of the operation parameters, system efficiency of the proposed ocean thermal energy conversion power cycle was 2.47%, relatively 15% higher than that of the basic ocean thermal energy conversion power cycle (2.2%.

  15. Assessment of control strategies for fault ride through of SCIG-based wind energy conversion systems

    Directory of Open Access Journals (Sweden)

    Manaullah

    2016-01-01

    Full Text Available With increasing penetration of wind energy into the power grid, researchers have started focusing more on control and coordination of wind energy conversion systems (WECS with the other components at system level, especially during fault. It is important to implement a suitable fault ride through control strategy to avoid tripping of the generators when the power system is subjected to voltage dips normally below 90% of nominal voltage. The dips below 90% may lead to a significant loss of generation and frequency collapse, followed by a blackout. This article implements and assesses the methodologies to deal with such situations for squirrel cage induction generator-based wind energy conversion systems employing fully rated power electronic converters. Three distinct control techniques—namely, balanced positive sequence control, positive negative sequence control, and dual current control—have been simulated and applied to grid side converter of SCIG-based WECS. The performance of all the three control strategies has been compared and presented in this work. During this study, the system is subjected to the most common unsymmetrical line to ground (LG fault and most severe symmetrical LLL fault on grid for the purpose of anaysis.

  16. High-temperature nuclear closed Brayton cycle power conversion system for the space exploration initiative

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, D.J. (Allied-Signal Aerospace Company, Garrett Fluid Systems Division, 1300 West Warner Road, Tempe, Arizona 85284-2896 (US))

    1991-01-05

    The Space Exploration Initiative (SEI) has stated goals of colonizing the moon and conducting manned exploration of the planet Mars. Unlike previous ventures into space, both manned and unmanned, large quantities of electrical power will be required to provide the energy for lunar base sustenance and for highly efficient propulsion systems for the long trip to mars and return. Further, the requirement for electrical power of several megawatts will necessitate the use of nuclear reactor driven power conversion systems. This paper discusses a particle bed reactor closed Brayton cycle space power system that uses advanced materials technology to achieve a high-temperature, low-specific-weight modular system capable of providing the requisite electrical power for both a lunar base and a Mars flight vehicle propulsion system.

  17. Modeling Business Processes of the Social Insurance Fund in Information System Runa WFE

    Science.gov (United States)

    Kataev, M. Yu; Bulysheva, L. A.; Xu, Li D.; Loseva, N. V.

    2016-08-01

    Introduction - Business processes are gradually becoming a tool that allows you at a new level to put employees or to make more efficient document management system. In these directions the main work, and presents the largest possible number of publications. However, business processes are still poorly implemented in public institutions, where it is very difficult to formalize the main existing processes. Us attempts to build a system of business processes for such state agencies as the Russian social insurance Fund (SIF), where virtually all of the processes, when different inputs have the same output: public service. The parameters of the state services (as a rule, time limits) are set by state laws and regulations. The article provides a brief overview of the FSS, the formulation of requirements to business processes, the justification of the choice of software for modeling business processes and create models of work in the system Runa WFE and optimization models one of the main business processes of the FSS. The result of the work of Runa WFE is an optimized model of the business process of FSS.

  18. Permanent Magnet Synchronous Generator Driven Wind Energy Conversion System Based on Parallel Active Power Filter

    Directory of Open Access Journals (Sweden)

    FERDI Brahim

    2014-05-01

    Full Text Available This paper proposes a novel application of the instantaneous P-Q theory in a wind energy conversion system (WECS. The proposed WECS is formed by permanent magnet synchronous generator (PMSG wind turbine system connected to the grid through parallel active power filter (PAPF. PAPF uses the generated wind energy to feed loads connected at the point of common coupling (PPC, compensates current harmonics and injects the excess of this energy into the grid using P-Q theory as control method. To demonstrate the feasibility and the performance of the proposed control scheme, simulation of this wind system has been realized using MATLAB/SIMULINK software. Simulation results show the accuracy and validity of the proposed control scheme for the PMSGPAPF system.

  19. Speed-sensorless control strategy for multi-phase induction generator in wind energy conversion systems

    Directory of Open Access Journals (Sweden)

    Dumnić Boris P.

    2016-01-01

    Full Text Available Renewable energy sources, especially wind energy conversion systems (WECS, exhibit constant growth. Increase in power and installed capacity led to advances in WECS topologies. Multi-phase approach presents a new development direction, with several key advantages over three-phase systems. Paired with a sensorless control strategy, multi-phase machines are expected to take primacy over standard solutions. This paper presents speed sensorless vector control of an asymmetrical six-phase induction generator based on a model reference adaptive system (MRAS. Suggested topology and developed control algorithm show that sensorless control can yield appropriate dynamic characteristics for the use in WECS with increase in reliability and robustness. [Projekat Ministarstva nauke Republike Srbije, br. III 042004: Smart Electricity Distribution Grids Based on Distribution Management System and Distributed Generation

  20. Systems analysis research for energy conversion and utilization technologies (ECUT). FY 1985 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, J.J.; Gunn, M.E.; Levinson, T.M.

    1985-11-01

    This Annual Report highlights ECUT accomplishments in the Systems Analysis Project for FY 1985. The Systems Analysis Project was established in 1980 along with the ECUT Division. The Systems Analysis mission is to identify, analyze, and assess R and D needs and research program strategies for advanced conservation technologies. The PNL Systems Analysis staff conducts topical research, provides technical studies, and plans program activities in three areas related to energy conversion and utilization technologies: (1) technology assessment, (2) engineering analysis, and (3) project evaluation and review. This report summarizes the technical results and accomplishments of the FY 1985 projects. They relate mostly to tribology, improved ctalysts, regenerative heat exchangers, robotics and electronics industries, and bioprocessing.

  1. Evaluation of maximum power point tracking in hydrokinetic energy conversion systems

    Directory of Open Access Journals (Sweden)

    Jahangir Khan

    2015-11-01

    Full Text Available Maximum power point tracking is a mature control issue for wind, solar and other systems. On the other hand, being a relatively new technology, detailed discussion on power tracking of hydrokinetic energy conversion systems are generally not available. Prior to developing sophisticated control schemes for use in hydrokinetic systems, existing know-how in wind or solar technologies can be explored. In this study, a comparative evaluation of three generic classes of maximum power point scheme is carried out. These schemes are (a tip speed ratio control, (b power signal feedback control, and (c hill climbing search control. In addition, a novel concept for maximum power point tracking: namely, extremum seeking control is introduced. Detailed and validated system models are used in a simulation environment. Potential advantages and drawbacks of each of these schemes are summarised.

  2. Applying systemic functional linguistics to conversations with dementia: the linguistic construction of relationships between participants.

    Science.gov (United States)

    Müller, Nicole; Mok, Zaneta

    2012-02-01

    Social isolation in dementia is a growing concern as the incidence and prevalence of dementing conditions is on the rise in many societies. Positive social interactions, which foster the construction and enactment of positive interpersonal relationships and therefore positive discursive identities, make an important contribution to emotional well-being. In this article, we investigate how two women diagnosed with dementia of the Alzheimer's type use language to relate to each other and two visiting graduate students. We use Systemic Functional Linguistics as an analytical framework, specifically investigating the use of vocatives and naming, and conversational moves and exchanges. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. A statistical analysis of wind speed data used in installation of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kavak Akpinar, E. [Firat University, Elazig (Turkey). Mechanical Engineering Dept.; Akpinar, S. [Firat University, Elazig (Turkey). Physics Dept.

    2005-03-01

    Wind speed is the most important parameter in the design and study of wind energy conversion systems. In this study, statistical methods were used to analyze the wind speed data of Keban-Elazig in the east region of Turkey. Measured hourly time series of wind speed data were obtained from the State Meteorological Station in Keban-Elazig over a five-year period from 1998 to 2002. The probability density distributions are derived from the time series data and the distributional parameters are identified. Two probability density functions are fitted to the measured probability distributions on a yearly basis. (author)

  4. Generators for Wind Energy Conversion Systems: State of the Art and Coming Attractions

    Directory of Open Access Journals (Sweden)

    Y. Amirat*

    2007-03-01

    Full Text Available Wind Energy Conversion Systems (WECS have become a focal point in the research of renewable energy sources. This paper provides then a comparative study of past and present generator technologies used in WECS. This study is based on an exhaustive review of the state of the art and on an effective comparison of the performances of the four main topologies that are permanent magnet generators, synchronous generators, induction generators and doubly-fed induction generators. The different generator-WECS schemes are compared on the basis of topology, cost, efficiency, power consumption and control complexity. Moreover, attempts are made to highlight future issues so as to index some emerging solutions.

  5. Glossary of terms and table of conversion factors used in design of chemical propulsion systems

    Science.gov (United States)

    Keller, R. B., Jr. (Compiler)

    1979-01-01

    The glossary presented is based entirely on terms used in the monographs on Chemical Propulsion. Significant terms relating to material properties and to material fabrication are presented. The terms are arranged in alphabetical order, with multiple word terms appearing in the normal sequence of usage; for example, ablative cooling appears as such, not as cooling, ablative, and lip seal appears as such, not as seal, lip. Conversion Factors for converting U.S. customary units to the International System of Units are presented in alphabetical order of the physical quantity (e.g., density, heat flux, specific impulse) involved.

  6. Bioenergy conversion and storage systems: from conventional electrochemical cells to hybrid bioelectronic devices

    DEFF Research Database (Denmark)

    Pankratov, Dmitrii; Chi, Qijin

    2017-01-01

    machinery for direct conversion of solar energy into electric power, is one of the most promising prospects for green and selfsustainablev energy harvesting. In addition, utilizing the inherent capacitance of electrodes as an activecharge-storing element enables to enhance the efficiency of electron...... transfer processes proceeding in the system and further miniaturization and simplification of a full-function device by elimination of internal capacitors in the electronic circuit. Remarkably, some pioneering attempts to design and create hybrid bioelectrochemical cells have already shown the positive...

  7. Flexible Mode Control of Grid Connected Wind Energy Conversion System Using Wavelet

    Directory of Open Access Journals (Sweden)

    Bhavna Jain

    2015-01-01

    Full Text Available Small wind turbine systems offer services to critical loads during grid faults and also connected back to grid in normal condition. The connection of a wind energy conversion system to the grid requires a robust phase locked loop (PLL and continuous monitoring of the grid conditions such as overvoltage, undervoltage, overfrequency, underfrequency, and grid outages. This paper describes a flexible control operation to operate a small wind turbine in both stand-alone mode via planned islanding and grid connected mode as well. In particular, a proper monitoring and control algorithm is required for transition between the modes. A wavelet based energy function is used for detection of grid disturbances as well as recovery of grid so that transition between the modes is made. To obtain good power quality LCL filter is used to reduce ripples. PLL is used for synchronization whenever mode changes from stand-alone to grid connected. Simulation results from a 10 kW wind energy conversion system are included to show the usefulness of the proposed methods. The control method is tested by generated gate pulses for single phase bridge inverter using field programmable gate array (FPGA.

  8. Conversion between EIT and Fano spectra in a microring-Bragg grating coupled-resonator system

    Science.gov (United States)

    Zhang, Zecen; Ng, Geok Ing; Hu, Ting; Qiu, Haodong; Guo, Xin; Wang, Wanjun; Rouifed, Mohamed Saïd; Liu, Chongyang; Wang, Hong

    2017-08-01

    A conversion between the electromagnetically induced transparency (EIT) transmission and Fano transmission is theoretically and experimentally demonstrated in an all-pass microring-Bragg grating (APMR-BG) coupled-resonator system. In this work, the coupling between the two resonators (the microring resonator and the Fabry-Perot resonator formed by two Bragg gratings) gives rise to the EIT and Fano transmissions. The resonant status strongly depends on the round-trip attenuation of the microring and the coupling strength. By tuning the coupling strength, the EIT and Fano transmissions can be controlled and converted. The device performance has been theoretically calculated and analyzed with a specially developed numerical model based on the transfer matrix method. The APMR-BG coupled-resonator systems with different gap widths were designed, fabricated, and characterized on a silicon-on-insulator (SOI) platform. The conversion of resonance was experimentally observed and verified. In addition, this on-chip system has the advantage of a small footprint, and the fabrication process is compatible with the planar waveguide fabrication process.

  9. Pension Fund

    CERN Multimedia

    2004-01-01

    The Governing Board of the Pension Fund held its one-hundred-and-twenty-second meeting on 3 February 2004. Opening the meeting, the Chairman, J. Bezemer, welcomed W. Zapf's alternate T. Lagrange, A. Naudi's alternate P. Geeraert, and M. Goossens' alternate M. Vitasse, who were attending the Governing Board for the first time. The Governing Board heard a report from its Chairman on the meeting of the CERN Council on 19 December 2003, at which, under Pension Fund matters, the Council had approved a pensions adjustment of 0.7%. The Governing Board then heard a report on the main elements of the Investment Committee's meeting on 3 December 2003. During a presentation, Expert Timing System (Madrid) and the Compagnie de Trésorerie Benjamin de Rothschild (Geneva) had proposed a bond portfolio investment following the same quantitative investment principles as the equities portfolio they already managed for the Fund. After some deliberation, the Investment Committee had decided, on that basis, to award t...

  10. Coordinated Operation of the Electricity and Natural Gas Systems with Bi-directional Energy Conversion

    DEFF Research Database (Denmark)

    Zeng, Qing; Zhang, Baohua; Fang, Jiakun

    2017-01-01

    A coordinated operation of the natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables. This work focuses on the unified optimal operation of the integrated natural gas and electricity system considering the network...... constraints in both systems. An iterative method is proposed to deal with the nonlinearity in the proposed model. The models of the natural gas and power system are linearized in every iterative step. Simulation results demonstrate the effectiveness of the approach. Applicability of the proposed method...... is tested in the sample case. Finally, the effect of Power to Gas (P2G) on the daily economic dispatch is also investigated....

  11. Does laser diode irradiation improve the degree of conversion of simplified dentin bonding systems?

    Directory of Open Access Journals (Sweden)

    Leticia Ferreira de Freitas BRIANEZZI

    Full Text Available Abstract Simplified dentin-bonding systems are clinically employed for most adhesive procedures, and they are prone to hydrolytic degradation. Objective This study aimed to investigate the effect of laser diode irradiation on the degree of conversion (DC, water sorption (WS, and water solubility (WSB of these bonding systems in an attempt to improve their physico-mechanical resistance. Material and Methods Two bonding agents were tested: a two-step total-etch system [Adper™ Single Bond 2, 3M ESPE (SB] and a universal system [Adper™ Single Bond Universal, 3M ESPE (SU]. Square-shaped specimens were prepared and assigned into 4 groups (n=5: SB and SU (control groups – no laser irradiation and SB-L and SU-L [SB and SU laser (L – irradiated groups]. DC was assessed using Fourier transform infrared spectroscopy with attenuated total reflectance. Additional uncured resin samples (≈3.0 µL, n=5 of each adhesive were also scanned for final DC calculation. For WS/WSB tests, similar specimens (n=10 were prepared and measured by monitoring the mass changes after dehydration/water storage cycles. For both tests, adhesive fluids were dropped into standardized Teflon molds (6.0×6.0×1.0 mm, irradiated with a 970-nm laser diode, and then polymerized with an LED-curing unit (1 W/cm2. Results Laser irradiation immediately before photopolymerization increased the DC (% of the tested adhesives: SB-L>SB>SU-L>SU. For WS/WSB (μg/mm3, only the dentin bonding system (DBS was a significant factor (pSU. Conclusion Irradiation with a laser diode improved the degree of conversion of all tested simplified dentin bonding systems, with no impact on water sorption and solubility.

  12. Assessment of materials technology of pressure vessels and piping for coal conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Canonico, D.A.; Cooper, R.H.; Foster, B.E.; McClung, R.W.; Nanstad, R.K.; Robinson, G.C.; Slaughter, G.M.

    1978-08-01

    The current technology of the materials, fabrication, and inspection of pressure vessels and piping for commercial coal conversion systems is reviewed. Comparison is made between the various codes applicable to these conversion systems. Areas of concern, such as material compatibility and fracture toughness, are cited. Recommendations are made that should increase the reliability of these components, the failure of which would result in a major outage of the plant. We believe that to date most of the current studies of various competing processes have emphasized the capital cost aspects to show potential competition with other energy sources but have not adequately examined the influence of design features on both potential maintenance and disruptive failure costs. It appears, for example, that the choice of vessel size (which is dictated by single vs multiple train process designs) has been examined primarily from the standpoint of capital costs. Maintenance, operation, relative part load capability, and relative probability of failure are unanswered questions. The materials having the most favorable mechanical properties and costs, unfortunately, are sensitive to various embrittling phenomena.

  13. Initial Test Results of a Dual Closed-Brayton-Cycle Power Conversion System

    Science.gov (United States)

    Johnson, Paul K.; Mason, Lee S.

    2007-01-01

    The dual Brayton power conversion system constructed for NASA Glenn Research Center (GRC) was acceptance tested April 2007 at Barber-Nichols, Inc., Arvada, Colorado. This uniquely configured conversion system is built around two modified commercial Capstone C30 microturbines and employs two closed-Brayton-cycle (CBC) converters sharing a common gas inventory and common heat source. Because both CBCs share the gas inventory, behavior of one CBC has an impact on the performance of the other CBC, especially when one CBC is standby or running at a different shaft speed. Testing performed to date includes the CBCs operating at equal and unequal shaft speeds. A test was also conducted where one CBC was capped off and the other was operated as a single CBC converter. The dual Brayton configuration generated 10.6 kWe at 75 krpm and a turbine inlet temperature of 817 K. Single Brayton operation generated 14.8 kWe at 90 krpm and a turbine inlet temperature of 925 K.

  14. Hybrid photovoltaic-thermoelectric system for concentrated solar energy conversion: Experimental realization and modeling

    Science.gov (United States)

    Beeri, Ofer; Rotem, Oded; Hazan, Eden; Katz, Eugene A.; Braun, Avi; Gelbstein, Yaniv

    2015-09-01

    An experimental demonstration of the combined photovoltaic (PV) and thermoelectric conversion of concentrated sunlight (with concentration factor, X, up to ˜300) into electricity is presented. The hybrid system is based on a multi-junction PV cell and a thermoelectric generator (TEG). The latter increases the electric power of the system and dissipates some of the excessive heat. For X ≤ 200, the system's maximal efficiency, ˜32%, was mostly due to the contribution from the PV cell. With increasing X and system temperature, the PV cell's efficiency decreased while that of the TEG increased. Accordingly, the direct electrical contribution of the TEG started to dominate in the total system power, reaching ˜20% at X ≈ 290. Using a simple steady state finite element modeling, the cooling effect of the TEG on the hybrid system's efficiency was proved to be even more significant than its direct electrical contribution for high solar concentrations. As a result, the total efficiency contribution of the TEG reached ˜40% at X ≈ 200. This suggests a new system optimization concept that takes into account the PV cell's temperature dependence and the trade-off between the direct electrical generation and cooling capabilities of the TEG. It is shown that the hybrid system has a real potential to exceed 50% total efficiency by using more advanced PV cells and TE materials.

  15. Funding and organisation of emergency preparedness in telecommunications and electrical power supply systems

    Energy Technology Data Exchange (ETDEWEB)

    #Latin Capital Letter O With Stroke#stby, Eirik; Hagen, Janne Merete; Nystuen, Kjell Olav

    2000-01-15

    A series of two joint projects between the Directorate for Civil Defence and Emergency Planning and FFI have as main objectives to identify critical vulnerabilities in the national Telecommunications and Electrical Power Supply infrastructures. These objectives include to clarify consequences of service outages, and to evaluate various efforts to reduce the vulnerabilities and the consequences. This report presents the results of a study on the following subjects with respect to emergency preparedness within the two sectors: Legislation and organisation, Historical funding, Discussion of future models for funding. The study concludes that fundings for emergency preparedness have been reduced during the last years. This is worrying in relation to the fact that these infrastructures are increasing vulnerable, and are natural targets for incidents in peacetime as well as in war. The funding models ought to be reviewed in accordance to the ongoing transitions in market and technical developments. (author)

  16. Experimental demonstration of information to energy conversion in a quantum system at the Landauer limit.

    Science.gov (United States)

    Peterson, J P S; Sarthour, R S; Souza, A M; Oliveira, I S; Goold, J; Modi, K; Soares-Pinto, D O; Céleri, L C

    2016-04-01

    Landauer's principle sets fundamental thermodynamical constraints for classical and quantum information processing, thus affecting not only various branches of physics, but also of computer science and engineering. Despite its importance, this principle was only recently experimentally considered for classical systems. Here we employ a nuclear magnetic resonance set-up to experimentally address the information to energy conversion in a quantum system. Specifically, we consider a three nuclear spins [Formula: see text] (qubits) molecule-the system, the reservoir and the ancilla-to measure the heat dissipated during the implementation of a global system-reservoir unitary interaction that changes the information content of the system. By employing an interferometric technique, we were able to reconstruct the heat distribution associated with the unitary interaction. Then, through quantum state tomography, we measured the relative change in the entropy of the system. In this way, we were able to verify that an operation that changes the information content of the system must necessarily generate heat in the reservoir, exactly as predicted by Landauer's principle. The scheme presented here allows for the detailed study of irreversible entropy production in quantum information processors.

  17. Robust Fault Detection of Wind Energy Conversion Systems Based on Dynamic Neural Networks

    Directory of Open Access Journals (Sweden)

    Nasser Talebi

    2014-01-01

    Full Text Available Occurrence of faults in wind energy conversion systems (WECSs is inevitable. In order to detect the occurred faults at the appropriate time, avoid heavy economic losses, ensure safe system operation, prevent damage to adjacent relevant systems, and facilitate timely repair of failed components; a fault detection system (FDS is required. Recurrent neural networks (RNNs have gained a noticeable position in FDSs and they have been widely used for modeling of complex dynamical systems. One method for designing an FDS is to prepare a dynamic neural model emulating the normal system behavior. By comparing the outputs of the real system and neural model, incidence of the faults can be identified. In this paper, by utilizing a comprehensive dynamic model which contains both mechanical and electrical components of the WECS, an FDS is suggested using dynamic RNNs. The presented FDS detects faults of the generator's angular velocity sensor, pitch angle sensors, and pitch actuators. Robustness of the FDS is achieved by employing an adaptive threshold. Simulation results show that the proposed scheme is capable to detect the faults shortly and it has very low false and missed alarms rate.

  18. Robust fault detection of wind energy conversion systems based on dynamic neural networks.

    Science.gov (United States)

    Talebi, Nasser; Sadrnia, Mohammad Ali; Darabi, Ahmad

    2014-01-01

    Occurrence of faults in wind energy conversion systems (WECSs) is inevitable. In order to detect the occurred faults at the appropriate time, avoid heavy economic losses, ensure safe system operation, prevent damage to adjacent relevant systems, and facilitate timely repair of failed components; a fault detection system (FDS) is required. Recurrent neural networks (RNNs) have gained a noticeable position in FDSs and they have been widely used for modeling of complex dynamical systems. One method for designing an FDS is to prepare a dynamic neural model emulating the normal system behavior. By comparing the outputs of the real system and neural model, incidence of the faults can be identified. In this paper, by utilizing a comprehensive dynamic model which contains both mechanical and electrical components of the WECS, an FDS is suggested using dynamic RNNs. The presented FDS detects faults of the generator's angular velocity sensor, pitch angle sensors, and pitch actuators. Robustness of the FDS is achieved by employing an adaptive threshold. Simulation results show that the proposed scheme is capable to detect the faults shortly and it has very low false and missed alarms rate.

  19. A current controlled matrix converter for wind energy conversion systems based on permanent magnet synchronous generator

    Directory of Open Access Journals (Sweden)

    Naggar H. Saad

    2016-05-01

    Full Text Available The main challenges of wind energy conversion systems (WECS are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG based WECS with the grid. To achieve fast dynamic response with reduced current ripples, a hysteresis current control is utilized. The proposed control system decouples the active and reactive components of the PMSG current to extract the maximum power from the wind at a given wind velocity and to inject reactive power to the grid. Reactive power injection during the fault satisfying the grid-codes requirement. The proposed WECS has been modeled and simulated using PSCAD/EMTDC software package.

  20. Geographic Information Systems-Transportation ISTEA management systems server-net prototype pooled fund study: Phase B summary

    Energy Technology Data Exchange (ETDEWEB)

    Espinoza, J. Jr.; Dean, C.D.; Armstrong, H.M. [and others

    1997-06-01

    The Geographic Information System-Transportation (GIS-T) ISTEA Management Systems Server Net Prototype Pooled Fund Study represents the first national cooperative effort in the transportation industry to address the management and monitoring systems as well as the statewide and metropolitan transportation planning requirements of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA). The Study was initiated in November 1993 through the Alliance for Transportation Research and under the leadership of the New Mexico State Highway and Transportation Department. Sandia National Laboratories, an Alliance partner, and Geographic Paradigm Computing. Inc. provided technical leadership for the project. In 1992, the Alliance for Transportation Research, the New Mexico State Highway and Transportation Department, Sandia National Laboratories, and Geographic Paradigm Computing, Inc., proposed a comprehensive research agenda for GIS-T. That program outlined a national effort to synthesize new transportation policy initiatives (e.g., management systems and Intelligent Transportation Systems) with the GIS-T server net ideas contained in the NCHRP project {open_quotes}Adaptation of GIS to Transportation{close_quotes}. After much consultation with state, federal, and private interests, a project proposal based on this agenda was prepared and resulted in this Study. The general objective of the Study was to develop GIS-T server net prototypes supporting the ISTEA requirements for transportation planning and management and monitoring systems. This objective can be further qualified to: (1) Create integrated information system architectures and design requirements encompassing transportation planning activities and data. (2) Encourage the development of functional GIS-T server net prototypes. (3) Demonstrate multiple information systems implemented in a server net environment.

  1. Ocean Thermal Energy Conversion power system development. Phase I: preliminary design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-04

    Westinghouse has completed the Preliminary Design Phase for the Power System Development of the Ocean Thermal Energy Conversion (OTEC) Demonstration Plant project. This study included the development of a preliminary design for a Modular Application scaled power system (10MWe) and Heat Exchanger Test Articles, both based on the concept developed in the Conceptual Design Phase. The results of this study were used to improve the baseline design of the 50MWe module for the Commercial Size Power System, which was recommended for the demonstration plant by the conceptual design study. The 50MWe module was selected since it has the lowest cost, and since its size convincingly demonstrates that future economically viable commercial plants, having reliable operation with credible anticipated costs, are possible. Additional optimization studies on the size of the power system plus hull continue to identify 50MWe as the preferred minimum cost configuration. This study was limited to a closed cycle ammonia power system module, using a seawater temperature difference of 40/sup 0/F, and a surface platform/ship reference hull. This volume describes system operation, a complete test program to verify mechanical reliability and thermal performance, fabrication and installation operations, and a cost analysis. (WHK)

  2. Ocean Thermal Energy Conversion power system development. Phase I: preliminary design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-04

    Westinghouse has completed the Preliminary Desigh Phase for the Power System Development of the Ocean Thermal Energy Conversion (OTEC) Demonstration Plant project. This study included the development of a preliminary design for a Modular Application scaled power system (10MWe) and Heat Exchanger Test Articles, both based on the concept developed in the Conceptual Design Phase. The results of this study were used to improve the baseline design of the 50MWe module for the Commercial Size Power System, which was recommended for the demonstration plant by the conceptual design study. The 50MWe module was selected since it has the lowest cost, and since its size convincingly demonstrates that future economically viable commercial plants, having reliable operation with credible anticipated costs, are possible. Additional optimization studies on the size of the power system plus hull continue to identify 50MWe as the preferred minimum cost configuration. This study was limited to a closed cycle ammonia power system module, using a seawater temperature difference of 40/sup 0/F, and a surface platform/ship reference hull. This volume presents the preliminary design configuration and system optimization. (WHK)

  3. Exploring the influence of the Global Fund and the GAVI Alliance on health systems in conflict-affected countries.

    Science.gov (United States)

    Patel, Preeti; Cummings, Rachael; Roberts, Bayard

    2015-01-01

    Global Health Initiatives (GHIs) respond to high-impact communicable diseases in resource-poor countries, including health systems support, and are major actors in global health. GHIs could play an important role in countries affected by armed conflict given these countries commonly have weak health systems and a high burden of communicable disease. The aim of this study is to explore the influence of two leading GHIs, the Global Fund and the GAVI Alliance, on the health systems of conflict-affected countries. This study used an analytical review approach to identify evidence on the role of the Global Fund and the GAVI Alliance with regards to health systems support to 19 conflict-affected countries. Primary and secondary published and grey literature were used, including country evaluations from the Global Fund and the GAVI Alliance. The WHO heath systems building blocks framework was used for the analysis. There is a limited evidence-base on the influence of GHIs on health systems of conflict-affected countries. The findings suggest that GHIs are increasingly investing in conflict-affected countries which has helped to rapidly scale up health services, strengthen human resources, improve procurement, and develop guidelines and protocols. Negative influences include distorting priorities within the health system, inequitable financing of disease-specific services over other health services, diverting staff away from more essential health care services, inadequate attention to capacity building, burdensome reporting requirements, and limited flexibility and responsiveness to the contextual challenges of conflict-affected countries. There is some evidence of increasing engagement of the Global Fund and the GAVI Alliance with health systems in conflict-affected countries, but this engagement should be supported by more context-specific policies and approaches.

  4. Ocean Thermal Energy Conversion power system development. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-04

    This report covers the conceptual and preliminary design of closed-cycle, ammonia, ocean thermal energy conversion power plants by Westinghouse Electric Corporation. Preliminary designs for evaporator and condenser test articles (0.13 MWe size) and a 10 MWe modular experiment power system are described. Conceptual designs for 50 MWe power systems, and 100 MWe power plants are also descirbed. Design and cost algorithms were developed, and an optimized power system design at the 50 MWe size was completed. This design was modeled very closely in the test articles and in the 10 MWe Modular Application. Major component and auxiliary system design, materials, biofouling, control response, availability, safety and cost aspects are developed with the greatest emphasis on the 10 MWe Modular Application Power System. It is concluded that all power plant subsystems are state-of-practice and require design verification only, rather than continued research. A complete test program, which verifies the mechanical reliability as well as thermal performance, is recommended and described.

  5. Line filter design of parallel interleaved VSCs for high power wind energy conversion systems

    DEFF Research Database (Denmark)

    Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus

    2015-01-01

    The Voltage Source Converters (VSCs) are often connected in parallel in a Wind Energy Conversion System (WECS) to match the high power rating of the modern wind turbines. The effect of the interleaved carriers on the harmonic performance of the parallel connected VSCs is analyzed in this paper....... In order to achieve low switching losses, the 60 clamp Discontinuous PulseWidth Modulation (DPWM1) is used to modulate the VSCs. A step-by-step design procedure of the line filter, which ensures the desired harmonic performance under all operating conditions, is presented. The analytical harmonic solution...... limit. In order to achieve the desired filter performance with optimal values of the filter parameters, the use of a LC trap branch with the conventional LCL filter is proposed. The expressions for the resonant frequencies of the proposed line filter are derived and used in the design to selectively...

  6. Online Data Conversion for the LHCb Active Radiation Monitor System (ARMS)

    CERN Document Server

    Farrugia, Julia

    2015-01-01

    Active radiation monitors are distributed in and around the LHCb experiment in order to monitor the evolution of radiation dose and 1 MeV equivalent neutron fluence. The active monitors are connected to an online network and their raw voltage measurement can be read out via WinCC panels. However, the raw voltage measurements must be corrected before conversion into correct dose or fluence. Previous work by [1] included a signal correction algorithm that corrects the values offline. The aim of this work is to understand how the signal correction algorithm works, archive previously corrected values into a new database system that will be integrated to a WinCC graphical interface and modify the algorithm so that it may process new values online while using less time and computing resources.

  7. Ocean Thermal Energy Conversion program. EPFFEP program for OTEC structural systems

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, H.; Chen, W. F.

    1976-01-01

    A constitutive relation and failure criterion for concrete material under general three-dimensional stress states has been developed using the work-hardening theory of plasticity. The formulation has all the required properties of concrete and gives a close estimate to experimental stresses for complete general stress states. In order that the results of research be readily usable in the analysis of suboceanic structures such as the large shells proposed for adoption in the Ocean Thermal Energy Conversion program (OTEC), corresponding computer code called EPFFEP (Elastic Plastic Fracture Finite Element Program) is developed here to reflect this material response. This report describes the details of this program and its implementation on the computer system CDC 6400. It defines all the input and output of the program along with an example illustrating a typical application of EPFFEP modeling. Detail computer algorithm for the constitutive relations of concrete is also given in the form of flow charts.

  8. Recent progress in solution plasma-synthesized-carbon-supported catalysts for energy conversion systems

    Science.gov (United States)

    Lun Li, Oi; Lee, Hoonseung; Ishizaki, Takahiro

    2018-01-01

    Carbon-based materials have been widely utilized as the electrode materials in energy conversion and storage technologies, such as fuel cells and metal–air batteries. In these systems, the oxygen reduction reaction is an important step that determines the overall performance. A novel synthesis route, named the solution plasma process, has been recently utilized to synthesize various types of metal-based and heteroatom-doped carbon catalysts. In this review, we summarize cutting-edge technologies involving the synthesis and modeling of carbon-supported catalysts synthesized via solution plasma process, followed by current progress on the electrocatalytic performance of these catalysts. This review provides the fundamental and state-of-the-art performance of solution-plasma-synthesized electrode materials, as well as the remaining scientific and technological challenges for this process.

  9. The direct conversion of sugars into 2,5-furandicarboxylic acid in a triphasic system.

    Science.gov (United States)

    Yi, Guangshun; Teong, Siew Ping; Zhang, Yugen

    2015-04-13

    A one-pot conversion of sugars into 2,5-furandicarboxylic acid (FDCA) is demonstrated in a triphasic system: tetraethylammonium bromide (TEAB) or water-methyl isobutyl ketone (MIBK)-water. In this reaction, sugars are first converted into 5-hydroxymethylfurfural (HMF) in TEAB or water (Phase I). The HMF in Phase I is then extracted to MIBK (Phase II) and transferred to water (Phase III), where HMF is converted into FDCA. Phase II plays multiple roles: as a bridge for HMF extraction, transportation and purification. Overall FDCA yields of 78 % and 50 % are achieved from fructose and glucose respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Exergy analysis for resource conversion of the Chinese Society 1993 under the material product system

    Energy Technology Data Exchange (ETDEWEB)

    Chen, B.; Chen, G.Q. [National Laboratory for Complex Systems and Turbulence, Department of Mechanics and Engineering Science, Peking University, Beijing 100871 (China)

    2006-07-15

    The resource exergy conversion in Chinese society in 1993 under the material product system (MPS) was investigated. Major resources that entered the society were divided into subgroups and analyzed in detail. The end use was broken down into ten end-use sectors: the forestry industry, food industry, iron and steel industry, nonferrous metal industry, chemical industry, textile industry, transportation, households, commerce, other industry. The total exergy input was 62.9EJ, which was 53.3GJ/cap. The total exergy output contained 11.66EJ or 9.88GJ/cap, which was 19% of the total exergy input. One RMB (Chinese Renminbi) yuan ($ 0.17) corresponded to 3.37MJ resource exergy output. (author)

  11. The UTRC wind energy conversion system performance analysis for horizontal axis wind turbines (WECSPER)

    Science.gov (United States)

    Egolf, T. A.; Landgrebe, A. J.

    1981-01-01

    The theory for the UTRC Energy Conversion System Performance Analysis (WECSPER) for the prediction of horizontal axis wind turbine performance is presented. Major features of the analysis are the ability to: (1) treat the wind turbine blades as lifting lines with a prescribed wake model; (2) solve for the wake-induced inflow and blade circulation using real nonlinear airfoil data; and (3) iterate internally to obtain a compatible wake transport velocity and blade loading solution. This analysis also provides an approximate treatment of wake distortions due to tower shadow or wind shear profiles. Finally, selected results of internal UTRC application of the analysis to existing wind turbines and correlation with limited test data are described.

  12. Nonlinear Predictive Control of Wind Energy Conversion System Using Dfig with Aerodynamic Torque Observer

    Science.gov (United States)

    Kamel, Ouari; Mohand, Ouhrouche; Toufik, Rekioua; Taib, Nabil

    2015-01-01

    In order to improvement of the performances for wind energy conversions systems (WECS), an advanced control techniques must be used. In this paper, as an alternative to conventional PI-type control methods, a nonlinear predictive control (NPC) approach is developed for DFIG-based wind turbine. To enhance the robustness of the controller, a disturbance observer is designed to estimate the aerodynamic torque which is considered as an unknown perturbation. An explicitly analytical form of the optimal predictive controller is given consequently on-line optimization is not necessary The DFIG is fed through the rotor windings by a back-to-back converter controlled by Pulse Width Modulation (PWM), where the stator winding is directly connected to the grid. The presented simulation results show a good performance in trajectory tracking of the proposed strategy and rejection of disturbances is successfully achieved.

  13. Financial problems facing the manufacturers of small wind energy conversion systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bolle, T G

    1979-11-01

    The financial barriers faced by the manufacturers of small wind energy conversion systems (SWECS) are assessed and found to be similar to those faced by other start up businesses. However, these problems are found to be aggravated by the high expectations for accelerated SWECS industry growth in the face of moderate government support and lack of investment capital. The underlying conditions of limited SWECS entrepreneur business experience, the highly competitive venture capital market, the inability of existing financial institutions to aid infant busineses and public unawareness of SWECS are reviewed. Specific manufacturer-oriented recommendations and federal, state and regulatory policy-oriented recommendations are made. In addition, the dynamics of the SWECS commercialization process are assessed and the variety of financial institutions playing a role in this process is detailed. Issues related to inflation, tax policy, regulation and federal R and D procurement policies are analyzed.

  14. Clean energy systems in the subsurface. Production, storage and conversion. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Zhengmeng Michael; Were, Patrick (eds.) [Clausthal Univ. of Technology, Goslar (Germany). Energie-Forschungszentrum Niedersachsen (EFZN); Xie, Heping [Sichuan Univ., Chengdu (China)

    2013-04-01

    Recent research on Integrated Energy and Environmental Utilization of Deep Underground Space. Results of the 3{sup rd} Sino-German Conference ''Underground Storage of CO{sub 2} and Energy'', held at Goslar, Germany, 21-23 May 2013. Researchers and professionals from academia and industry discuss the future of deep underground space technologies for an integrated energy and environmental utilization. Anthropogenic greenhouse gas emissions, energy security and sustainability are three of the greatest contemporary global challenges today. This year the Sino-German Cooperation Group ''Underground Storage of CO{sub 2} and Energy'', is meeting on the 21-23 May 2013 for the second time in Goslar, Germany, to convene its 3{sup rd} Sino-German conference on the theme ''Clean Energy Systems in the Subsurface: Production, Storage and Conversion''.

  15. Bismarck meets Beveridge on the Silk Road: coordinating funding sources to create a universal health financing system in Kyrgyzstan

    Science.gov (United States)

    Ibraimova, Ainura; Jakab, Melitta; O’Dougherty, Sheila

    2009-01-01

    Abstract Options for health financing reform are often portrayed as a choice between general taxation (known as the Beveridge model) and social health insurance (known as the Bismarck model). Ten years of health financing reform in Kyrgyzstan, since the introduction of its compulsory health insurance fund in 1997, provide an excellent example of why it is wrong to reduce health financing policy to a choice between the Beveridge and Bismarck models. Rather than fragment the system according to the insurance status of the population, as many other low- and middle-income countries have done, the Kyrgyz reforms were guided by the objective of having a single system for the entire population. Key features include the role and gradual development of the compulsory health insurance fund as the single purchaser of health-care services for the entire population using output-based payment methods, the complete restructuring of pooling arrangements from the former decentralized budgetary structure to a single national pool, and the establishment of an explicit benefit package. Central to the process was the transformation of the role of general budget revenues – the main source of public funding for health – from directly subsidizing the supply of services to subsidizing the purchase of services on behalf of the entire population by redirecting them into the health insurance fund. Through their approach to health financing policy, and pooling in particular, the Kyrgyz health reformers demonstrated that different sources of funds can be used in an explicitly complementary manner to enable the creation of a unified, universal system. PMID:19649370

  16. Mass, Energy, Space And Time Systemic Theory--MEST--photoelectric conversion equation

    Science.gov (United States)

    Cao, Dayong

    2010-03-01

    Things have their physical system of the mass, energy, space and time of themselves-MEST. The time is from the frequency of wave, the space is from the amplitude of wave. In the system, the mass-energy is center and the space-time is around. In the general relativity, there is the equation: ma=mg . So get the equation: mar=mv^2=mgr. We use the data of the planets into this equation, and find it is right. (see the figure 1 and table 2) But the kinetic energy's equation is: Ek=mv^2/2mgr. How do explain it? Because the other kinetic energy's equations: Ek=δmc^2 like the wave's energy equation: E'=m'c^2. And things have both of the matter and the wave. So the equation belong to the wave. So the δm can be see like the increased mass of wave of the things. The matter's kinetic energy equal the wave's energy: mv^2/2=δmc^2=δm'c^2. And them give the things the repulsion force together. So the repulsion energy equation is: Er=mv^2=mv^2/2+δm'c^2=mar. The repulsion energy of the planets equal it's potential energy: Er=Ep=GMm/r=mgr. In photoelectron conversion, Not only there is a relationship between the wave and the kinetic energy of the photoelectron, but also there is a relationship between the wave and the mass of the photoelectron. So get the photoelectric conversion equation: m ev^2/2=δm'c^2-E= hν-E, and δm e= h/c λ-m e. The mass of the photoelectron is bigger than the electron's mass.

  17. Modeling of the interplay between single-file diffusion and conversion reaction in mesoporous systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jing [Iowa State Univ., Ames, IA (United States)

    2013-01-11

    We analyze the spatiotemporal behavior of species concentrations in a diffusion-mediated conversion reaction which occurs at catalytic sites within linear pores of nanometer diameter. A strict single-file (no passing) constraint occurs in the diffusion within such narrow pores. Both transient and steady-state behavior is precisely characterized by kinetic Monte Carlo simulations of a spatially discrete lattice–gas model for this reaction–diffusion process considering various distributions of catalytic sites. Exact hierarchical master equations can also be developed for this model. Their analysis, after application of mean-field type truncation approximations, produces discrete reaction–diffusion type equations (mf-RDE). For slowly varying concentrations, we further develop coarse-grained continuum hydrodynamic reaction–diffusion equations (h-RDE) incorporating a precise treatment of single-file diffusion (SFD) in this multispecies system. Noting the shortcomings of mf-RDE and h-RDE, we then develop a generalized hydrodynamic (GH) formulation of appropriate gh-RDE which incorporates an unconventional description of chemical diffusion in mixed-component quasi-single-file systems based on a refined picture of tracer diffusion for finite-length pores. The gh-RDE elucidate the non-exponential decay of the steady-state reactant concentration into the pore and the non-mean-field scaling of the reactant penetration depth. Then an extended model of a catalytic conversion reaction within a functionalized nanoporous material is developed to assess the effect of varying the reaction product – pore interior interaction from attractive to repulsive. The analysis is performed utilizing the generalized hydrodynamic formulation of the reaction-diffusion equations which can reliably capture the complex interplay between reaction and restricted transport for both irreversible and reversible reactions.

  18. A Power Supply System with ZVS and Current-Doubler Features for Hybrid Renewable Energy Conversion

    Directory of Open Access Journals (Sweden)

    Jye-Chau Su

    2013-09-01

    Full Text Available In this paper, a power supply system for hybrid renewable energy conversion is proposed, which can process PV (photovoltaic power and wind-turbine energy simultaneously for step-down voltage and high current applications. It is a dual-input converter and mainly contains a PV energy source, a wind turbine energy source, a zero-voltage-switching (ZVS forward converter, and a current-doubler rectifier. The proposed power supply system has the following advantages: (1 PV-arrays and wind-energy sources can alternatively deliver power to the load during climate or season alteration; (2 maximum power point tracking (MPPT can be accomplished for both different kinds of renewable-energy sources; (3 ZVS and synchronous rectification techniques for the active switches of the forward converter are embedded so as to reduce switching and conducting losses; and (4 electricity isolation is naturally obtained. To achieve an optimally dynamic response and to increase control flexibility, a digital signal processor (DSP is investigated and presented to implement MPPT algorithm and power regulating scheme. Finally, a 240 W prototype power supply system with ZVS and current-doubler features to deal with PV power and wind energy is built and implemented. Experimental results are presented to verify the performance and the feasibility of the proposed power supply system.

  19. [Conversion of L-cystine and L-cysteine to taurin by the enzyme systems of liver cells].

    Science.gov (United States)

    Soboleva, A V; Krasnoshtanova, A A; Krylov, I A

    2004-01-01

    The kinetics of conversion of sulfur-containing amino acids L-cystine and L-cysteine to taurin by the enzyme system of cattle liver cells was studied, and a mathematical model was developed. It was shown that L-cystine and L-cysteine conversion obeyed the Michaelis-Menten equations of serial-sequential conversions with regard to inhibition by the final product and inactivation. The yield of taurin under the optimized conditions of L-cystine and L-cysteine conversion (temperature, 40 degrees C; pH 1.5 and 3.0, respectively; and addition of enzyme preparations in five equal portions at 2-h intervals) was in the range 80-85% of the substrate weight.

  20. Designing research funding schemes to promote global health equity: An exploration of current practice in health systems research.

    Science.gov (United States)

    Pratt, Bridget; Hyder, Adnan A

    2016-11-23

    International research is an essential means of reducing health disparities between and within countries and should do so as a matter of global justice. Research funders from high-income countries have an obligation of justice to support health research in low and middle-income countries (LMICs) that furthers such objectives. This paper investigates how their current funding schemes are designed to incentivise health systems research in LMICs that promotes health equity. Semi-structured in-depth interviews were performed with 16 grants officers working for 11 funders and organisations that support health systems research: the Alliance for Health Policy and Systems Research, Comic Relief, Doris Duke Foundation, European Commission, International Development Research Centre, Norwegian Agency for Development Cooperation, Research Council of Norway, Rockefeller Foundation, UK Department of International Development, UK Medical Research Council, and Wellcome Trust. Thematic analysis of the data demonstrates their funding schemes promote health systems research with (up to) five key features that advance health equity: being conducted with worst-off populations, focusing on research topics that advance equitable health systems, having LMIC ownership of the research agenda, strengthening LMIC research capacity, and having an impact on health disparities. The different types of incentives that encouraged proposed projects to have these features are identified and classified by their strength (strong, moderate, weak). It is suggested that research funders ought to create and maintain funding schemes with strong incentives for the features identified above in order to more effectively help reduce global health disparities. © 2016 John Wiley & Sons Ltd.

  1. Self Adaptive Air Turbine for Wave Energy Conversion Using Shutter Valve and OWC Heoght Control System

    Energy Technology Data Exchange (ETDEWEB)

    Di Bella, Francis A

    2014-09-29

    An oscillating water column (OWC) is one of the most technically viable options for converting wave energy into useful electric power. The OWC system uses the wave energy to “push or pull” air through a high-speed turbine, as illustrated in Figure 1. The turbine is typically a bi-directional turbine, such as a Wells turbine or an advanced Dennis-Auld turbine, as developed by Oceanlinx Ltd. (Oceanlinx), a major developer of OWC systems and a major collaborator with Concepts NREC (CN) in Phase II of this STTR effort. Prior to awarding the STTR to CN, work was underway by CN and Oceanlinx to produce a mechanical linkage mechanism that can be cost-effectively manufactured, and can articulate turbine blades to improve wave energy capture. The articulation is controlled by monitoring the chamber pressure. Funding has been made available from the U.S. Department of Energy (DOE) to CN (DOE DE-FG-08GO18171) to co-share the development of a blade articulation mechanism for the purpose of increasing energy recovery. However, articulating the blades is only one of the many effective design improvements that can be made to the composite subsystems that constitute the turbine generator system.

  2. A Condensed Introduction to the Doubly Fed Induction Generator Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Julius Mwaniki

    2017-01-01

    Full Text Available The increase in wind power penetration, at 456 GW as of June 2016, has resulted in more stringent grid codes which specify that the wind energy conversion systems (WECS must remain connected to the system during and after a grid fault and, furthermore, must offer grid support by providing reactive currents. The doubly fed induction generator (DFIG WECS is a well-proven technology, having been in use in wind power generation for many years and having a large world market share due to its many merits. Newer technologies such as the direct drive gearless permanent magnet synchronous generator have come up to challenge its market share, but the large number of installed machines ensures that it remains of interest in the wind industry. This paper presents a concise introduction of the DFIG WECS covering its construction, operation, merits, demerits, modelling, control types, levels and strategies, faults and their proposed solutions, and, finally, simulation. Qualities for the optimal control strategy are then proposed. The paper is intended to cover major issues related to the DFIG WECS that are a must for an overview of the system and hence serve as an introduction especially for new entrants into this area of study.

  3. Hybrid Intelligent Control Method to Improve the Frequency Support Capability of Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Shin Young Heo

    2015-10-01

    Full Text Available This paper presents a hybrid intelligent control method that enables frequency support control for permanent magnet synchronous generators (PMSGs wind turbines. The proposed method for a wind energy conversion system (WECS is designed to have PMSG modeling and full-scale back-to-back insulated-gate bipolar transistor (IGBT converters comprising the machine and grid side. The controller of the machine side converter (MSC and the grid side converter (GSC are designed to achieve maximum power point tracking (MPPT based on an improved hill climb searching (IHCS control algorithm and de-loaded (DL operation to obtain a power margin. Along with this comprehensive control of maximum power tracking mode based on the IHCS, a method for kinetic energy (KE discharge control of the supporting primary frequency control scheme with DL operation is developed to regulate the short-term frequency response and maintain reliable operation of the power system. The effectiveness of the hybrid intelligent control method is verified by a numerical simulation in PSCAD/EMTDC. Simulation results show that the proposed approach can improve the frequency regulation capability in the power system.

  4. Impact of thermal energy storage properties on solar dynamic space power conversion system mass

    Science.gov (United States)

    Juhasz, Albert J.; Coles-Hamilton, Carolyn E.; Lacy, Dovie E.

    1987-01-01

    A 16 parameter solar concentrator/heat receiver mass model is used in conjunction with Stirling and Brayton Power Conversion System (PCS) performance and mass computer codes to determine the effect of thermal energy storage (TES) material property changes on overall PCS mass as a function of steady state electrical power output. Included in the PCS mass model are component masses as a function of thermal power for: concentrator, heat receiver, heat exchangers (source unless integral with heat receiver, heat sink, regenerator), heat engine units with optional parallel redundancy, power conditioning and control (PC and C), PC and C radiator, main radiator, and structure. Critical TES properties are: melting temperature, heat of fusion, density of the liquid phase, and the ratio of solid-to-liquid density. Preliminary results indicate that even though overall system efficiency increases with TES melting temperature up to 1400 K for concentrator surface accuracies of 1 mrad or better, reductions in the overall system mass beyond that achievable with lithium fluoride (LiF) can be accomplished only if the heat of fusion is at least 800 kJ/kg and the liquid density is comparable to that of LiF (1800 kg/cu m).

  5. 75 FR 7464 - Energy Efficient Building Systems Regional Innovation Cluster Initiative-Joint Federal Funding...

    Science.gov (United States)

    2010-02-19

    ... interested parties to learn about the Joint Federal Funding Opportunity Announcement (see http:// ] www... the area, the E-RIC will create an economically dynamic region focused on energy efficient buildings... webcast, and what organization you represent (if appropriate). Reasonable provision will be made to answer...

  6. High Quality Factor 80 MHz Microelectromechanical Systems Resonator Utilizing Torsional-to-Transverse Vibration Conversion

    Science.gov (United States)

    Kiso, Masaya; Okada, Mitsuhiro; Fujiura, Hideaki; Miyauchi, Hideo; Niki, Kazuya; Tanigawa, Hiroshi; Suzuki, Kenichiro

    2012-06-01

    A silicon microelectromechanical systems (MEMS) resonator utilizing torsional-to-transverse vibration conversion with quarter-wavelength torsional support beams is designed, fabricated, and evaluated. The resonant frequency for torsional modes mostly depends only on beam length, providing a large tolerance in the fabrication process. However, the following have remained critical issues: the increase in the quality factor (Q-factor) and the reduction in the motional resistance. We propose a new beam structure, in which the MEMS resonator utilizing torsional-to-transverse vibration conversion is anchored by four quarter-wavelength torsional support beams. First, the fabricated resonators are measured with a laser-Doppler (LD) vibrometer. The measured resonant frequency of 78.224 MHz has been in good agreement with the simulated one. The Q-factor has also been measured to be as high as 3.0×104 in vacuum. Then, the electrical characteristic is evaluated with an impedance analyzer. The Q-factor has been electrically measured to be as high as 3.1×104 in vacuum, which agrees well with the mechanically measured one of 3.0×104. The Q-factor has also been electrically measured to be as high as 1.3×104 at atmospheric pressure. In the measurement, a spring softening effect has been clearly observed. By increasing the DC bias voltage from 20 to 40 V, the resonant frequency has decreased by 640 Hz. The extracted motional resistance for a 0.1-µm-gap resonator has been greatly reduced to 0.039 MΩ at 5 V DC, owing to the narrow-gap effect, from that of a 0.25-µm-gap resonator. The tolerance in the fabrication process has also been evaluated and successfully verified from the measurement of the fabricated MEMS resonators.

  7. Modeling and Coordinated Control Strategy of Large Scale Grid-Connected Wind/Photovoltaic/Energy Storage Hybrid Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Lingguo Kong

    2015-01-01

    Full Text Available An AC-linked large scale wind/photovoltaic (PV/energy storage (ES hybrid energy conversion system for grid-connected application was proposed in this paper. Wind energy conversion system (WECS and PV generation system are the primary power sources of the hybrid system. The ES system, including battery and fuel cell (FC, is used as a backup and a power regulation unit to ensure continuous power supply and to take care of the intermittent nature of wind and photovoltaic resources. Static synchronous compensator (STATCOM is employed to support the AC-linked bus voltage and improve low voltage ride through (LVRT capability of the proposed system. An overall power coordinated control strategy is designed to manage real-power and reactive-power flows among the different energy sources, the storage unit, and the STATCOM system in the hybrid system. A simulation case study carried out on Western System Coordinating Council (WSCC 3-machine 9-bus test system for the large scale hybrid energy conversion system has been developed using the DIgSILENT/Power Factory software platform. The hybrid system performance under different scenarios has been verified by simulation studies using practical load demand profiles and real weather data.

  8. A multi-agent conversational system with heterogeneous data sources access

    KAUST Repository

    Eisman, Eduardo M.

    2016-01-28

    In many of the problems that can be found nowadays, information is scattered across different heterogeneous data sources. Most of the natural language interfaces just focus on a very specific part of the problem (e.g. an interface to a relational database, or an interface to an ontology). However, from the point of view of users, it does not matter where the information is stored, they just want to get the knowledge in an integrated, transparent, efficient, effective, and pleasant way. To solve this problem, this article proposes a generic multi-agent conversational architecture that follows the divide and conquer philosophy and considers two different types of agents. Expert agents are specialized in accessing different knowledge sources, and decision agents coordinate them to provide a coherent final answer to the user. This architecture has been used to design and implement SmartSeller, a specific system which includes a Virtual Assistant to answer general questions and a Bookseller to query a book database. A deep analysis regarding other relevant systems has demonstrated that our proposal provides several improvements at some key features presented along the paper.

  9. A Concise Presentation of Doubly Fed Induction Generator Wind Energy Conversion Systems Challenges and Solutions

    Directory of Open Access Journals (Sweden)

    Julius Mwaniki

    2017-01-01

    Full Text Available There is increased worldwide wind power generation, a large percentage of which is grid connected. The doubly fed induction generator (DFIG wind energy conversion system (WECS has many merits and, as a result, large numbers have been installed to date. The DFIG WECS operation, under both steady state and fault conditions, is of great interest since it impacts on grid performance. This review paper presents a condensed look at the various applied solutions to the challenges of the DFIG WECS including maximum power point tracking, common mode voltages, subsynchronous resonance, losses, modulation, power quality, and faults both internal and from the grid. It also looks at approaches used to meet the increasingly stringent grid codes requirements for the DFIG WECS to not only ride through faults but also provide voltage support. These are aspects of the DFIG WECS that are critical for system operators and prospective investors and can also serve as an introduction for new entrants into this area of study.

  10. Maximum-power-point tracking with reduced mechanical stress applied to wind-energy-conversion-systems

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, L.G. [Departamento de Electronica y Comunicaciones, Universidad de los Andes, nucleo la Hechicera, 5101 Merida (Venezuela); Figueres, E.; Garcera, G. [Grupo de Sistemas Electronicos Industriales, Universidad Politecnica de Valencia, Camino de vera s/n, 46022 Valencia (Spain); Carranza, O. [Escuela Superior de Computo, Instituto Politecnico Nacional, Av. Juan de Dios Batiz s/n, 07738 DF (Mexico)

    2010-07-15

    This paper presents an improved maximum-power-point tracking algorithm for wind-energy-conversion-systems. The proposed method significantly reduces the turbine mechanical stress with regard to conventional techniques, so that both the maintenance needs and the medium time between failures are expected to be improved. To achieve these objectives, a sensorless speed control loop receives its reference signal from a modified Perturb and Observe algorithm, in which the typical steps on the reference speed have been substituted by a fixed and well-defined slope ramp signal. As a result, it is achieved a soft dynamic response of both the torque and the speed of the wind turbine, so that the whole system suffers from a lower mechanical stress than with conventional P and O techniques. The proposed method has been applied to a wind turbine based on a permanent magnet synchronous generator operating at variable speed, which is connected to the distribution grid by means of a back to back converter. (author)

  11. The preparation of high conversion polymeric systems containing eugenol residues and their rheological characterization.

    Science.gov (United States)

    Rojo, Luis; Borzacchiello, Assunta; Parra, Juan; Deb, Sanjukta; Vázquez, Blanca; San Román, Julio

    2008-04-01

    Copolymeric systems bearing eugenol covalently linked to the macromolecular chains have been prepared and characterised in terms of thermal, rheological and in vitro behaviour. Eugenyl methacrylate (EgMA) and ethoxyeugenyl methacrylate (EEgMA) were polymerized and copolymerized with ethyl methacrylate (EMA) in a wide range of feed composition by bulk at high conversion. Glass transition temperature (Tg) increased with the content of EgMA in the copolymer whereas Tg decreased with the content of EEgMA. The presence of any of the eugenyl monomers in the copolymer increased the thermal stability of the materials. Rheological analysis showed that EMA-co-EgMA copolymers present a higher density of crosslinking or entanglements among the chains compared with EMA-co-EEgMA materials, and copolymers containing more than 40% EgMA exhibited a pseudo-solid like behaviour with G' relatively independent of the frequency. The average molecular weight between cross-links (Mc) for the latter copolymers was in the order of 10(4) Da. For EEgMA copolymers, tan delta was lower than unity and G' showed a gradual and slight dependency with frequency over the whole range of composition. In vitro behaviour showed a higher hydrophilicity of the EEgMA containing copolymers manifested in higher water sorption values, lower water contact angle values and higher surface free energy due to an increase in polarity. All systems presented a good cytocompatibility with human fibroblasts assessed through direct and indirect assays.

  12. Ecological and socio-economic functions across tropical land use systems after rainforest conversion.

    Science.gov (United States)

    Drescher, Jochen; Rembold, Katja; Allen, Kara; Beckschäfer, Philip; Buchori, Damayanti; Clough, Yann; Faust, Heiko; Fauzi, Anas M; Gunawan, Dodo; Hertel, Dietrich; Irawan, Bambang; Jaya, I Nengah S; Klarner, Bernhard; Kleinn, Christoph; Knohl, Alexander; Kotowska, Martyna M; Krashevska, Valentyna; Krishna, Vijesh; Leuschner, Christoph; Lorenz, Wolfram; Meijide, Ana; Melati, Dian; Nomura, Miki; Pérez-Cruzado, César; Qaim, Matin; Siregar, Iskandar Z; Steinebach, Stefanie; Tjoa, Aiyen; Tscharntke, Teja; Wick, Barbara; Wiegand, Kerstin; Kreft, Holger; Scheu, Stefan

    2016-05-19

    Tropical lowland rainforests are increasingly threatened by the expansion of agriculture and the extraction of natural resources. In Jambi Province, Indonesia, the interdisciplinary EFForTS project focuses on the ecological and socio-economic dimensions of rainforest conversion to jungle rubber agroforests and monoculture plantations of rubber and oil palm. Our data confirm that rainforest transformation and land use intensification lead to substantial losses in biodiversity and related ecosystem functions, such as decreased above- and below-ground carbon stocks. Owing to rapid step-wise transformation from forests to agroforests to monoculture plantations and renewal of each plantation type every few decades, the converted land use systems are continuously dynamic, thus hampering the adaptation of animal and plant communities. On the other hand, agricultural rainforest transformation systems provide increased income and access to education, especially for migrant smallholders. Jungle rubber and rubber monocultures are associated with higher financial land productivity but lower financial labour productivity compared to oil palm, which influences crop choice: smallholders that are labour-scarce would prefer oil palm while land-scarce smallholders would prefer rubber. Collecting long-term data in an interdisciplinary context enables us to provide decision-makers and stakeholders with scientific insights to facilitate the reconciliation between economic interests and ecological sustainability in tropical agricultural landscapes. © 2016 The Authors.

  13. Speech-To-Text Conversion STT System Using Hidden Markov Model HMM

    Directory of Open Access Journals (Sweden)

    Su Myat Mon

    2015-06-01

    Full Text Available Abstract Speech is an easiest way to communicate with each other. Speech processing is widely used in many applications like security devices household appliances cellular phones ATM machines and computers. The human computer interface has been developed to communicate or interact conveniently for one who is suffering from some kind of disabilities. Speech-to-Text Conversion STT systems have a lot of benefits for the deaf or dumb people and find their applications in our daily lives. In the same way the aim of the system is to convert the input speech signals into the text output for the deaf or dumb students in the educational fields. This paper presents an approach to extract features by using Mel Frequency Cepstral Coefficients MFCC from the speech signals of isolated spoken words. And Hidden Markov Model HMM method is applied to train and test the audio files to get the recognized spoken word. The speech database is created by using MATLAB.Then the original speech signals are preprocessed and these speech samples are extracted to the feature vectors which are used as the observation sequences of the Hidden Markov Model HMM recognizer. The feature vectors are analyzed in the HMM depending on the number of states.

  14. Solar-energy conversion system provides electrical power and thermal control for life-support systems

    Science.gov (United States)

    Davis, B. K.

    1974-01-01

    System utilizes Freon cycle and includes boiler turbogenerator with heat exchanger, regenerator and thermal-control heat exchangers, low-pressure and boiler-feed pumps, and condenser. Exchanger may be of interest to engineers and scientists investigating new energy sources.

  15. Comparative Analysis of TIAA/CREF and North Dakota Public Employee Retirement System Pension Fund. North Dakota Economic Studies Number 55.

    Science.gov (United States)

    Lee, Jeong W.

    Quantitative financial measures were applied to evaluate the performance of the North Dakota Public Employee Retirement System (NDPERS) pension fund portfolios and the Teachers Insurance and Annuity Association (TIAA)/College Retirement Equities Fund (CREF) portfolios, thus providing a relative performance assessment. Ten years of data were…

  16. Gambling on change. Five big systems buy into a venture capital fund to try to reap profits from the transformation of healthcare.

    Science.gov (United States)

    Evans, Melanie

    2011-01-31

    Five healthcare systems have financed a venture-capital fund with hopes for a financial and operational return. Executives say the investment is a way to influence technological developments and evaluate products and software. James Bosscher, chief investment officer at Trinity Health, left, said Heritage fund investments will target health information technology.

  17. Demonstrating Hybrid Heat Transport and Energy Conversion System Performance Characterization Using Intelligent Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ostrum, Lee [Univ. of Idaho and Idaho Falls Center, Idaho Falls, ID (United States); Manic, Milos [Virginia Commonwealth Univ., Richmond, VA (United States)

    2017-09-28

    The debate continues on the magnitude and validity of climate change caused by human activities. However, there is no debate about the need to make buildings, modes of transportation, factories, and homes as energy efficient as possible. Given that climate change could occur with the wasteful use of fossil fuel and the fact that fossil energy costs could and will swing wildly, it is imperative that every effort be made to utilize energy sources to their fullest. Hybrid energy systems (HES) are two or more separate energy producers used together to produce energy commodities. The HES this report focuses on is the use of nuclear reactor waste heat as a source of further energy utilization. Nuclear reactors use a fluid to cool the core and produce the steam needed for the production of electricity. Traditionally this steam, or coolant, is used to convert the energy then cooled elsewhere. The heat is released into the environment without being used further. By adding technologies to nuclear reactors to use the wasted heat, a system can be developed to make more than just electricity and allow for loading following capabilities.

  18. Thermophotovoltaic energy conversion system having a heavily doped n-type region

    Science.gov (United States)

    DePoy, David M.; Charache, Greg W.; Baldasaro, Paul F.

    2000-01-01

    A thermophotovoltaic (TPV) energy conversion semiconductor device is provided which incorporates a heavily doped n-type region and which, as a consequence, has improved TPV conversion efficiency. The thermophotovoltaic energy conversion device includes an emitter layer having first and second opposed sides and a base layer in contact with the first side of the emitter layer. A highly doped n-type cap layer is formed on the second side of the emitter layer or, in another embodiment, a heavily doped n-type emitter layer takes the place of the cap layer.

  19. Maintenance for power conversion system of gas turbine high temperature reactor (GTHTR300). Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Kosugiyama, Shinichi; Takada, Shoji; Katanishi, Shoji; Yan, Xing; Takizuka, Takakazu; Kunitomi, Kazuhiko [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2002-11-01

    In order to be a suitable next generation nuclear power plant from reliable and economical points of view, it is necessary for GTHTR300 to have good maintenability and inspectability. Appropriate maintenance concept for the power conversion system of GTHTR300 consisting of a gas turbine, a compressor, a generator, a recuperator, a precooler and so on was studied based on results of the basic design of GTHTR300 in fiscal 2001. Considering degradation phenomena which could occur on each objective equipment, it is technically possible to reduce several maintenance items and extend maintenance interval for some equipment compared to those for existing LWR power plants and combined cycle fossil power plants. But owing to structural feature and installed location of each equipment, and fission product plate-out on each equipment, it became clear that some problems must be solved for making the maintenance works realistic and efficient. Solving the problems and confirming appropriateness of the proposed maintenance concept and plans will be done in coming detailing work of GTHTR300 design. (author)

  20. Rapid cell-surface prion protein conversion revealed using a novel cell system

    Science.gov (United States)

    Goold, R.; Rabbanian, S.; Sutton, L.; Andre, R.; Arora, P.; Moonga, J.; Clarke, A.R.; Schiavo, G.; Jat, P.; Collinge, J.; Tabrizi, S.J.

    2011-01-01

    Prion diseases are fatal neurodegenerative disorders with unique transmissible properties. The infectious and pathological agent is thought to be a misfolded conformer of the prion protein. Little is known about the initial events in prion infection because the infecting prion source has been immunologically indistinguishable from normal cellular prion protein (PrPC). Here we develop a unique cell system in which epitope-tagged PrPC is expressed in a PrP knockdown (KD) neuroblastoma cell line. The tagged PrPC, when expressed in our PrP-KD cells, supports prion replication with the production of bona fide epitope-tagged infectious misfolded PrP (PrPSc). Using this epitope-tagged PrPSc, we study the earliest events in cellular prion infection and PrP misfolding. We show that prion infection of cells is extremely rapid occurring within 1 min of prion exposure, and we demonstrate that the plasma membrane is the primary site of prion conversion. PMID:21505437

  1. Analysis Of Functional Stability Of The Triphased Asynchronous Generator Used In Conversion Systems Of A Eolian Energy Into Electric Energy

    Directory of Open Access Journals (Sweden)

    Ion VONCILA

    2003-12-01

    Full Text Available This paper presents a study of the influence of the main perturbation agent over the functional stability of the triphased asynchronous generator (for the two alternative: with coiled and short circuit rotor, used for the conversion systems from a eolian energy into electric energy.

  2. L1 Adaptive Speed Control of a Small Wind Energy Conversion System for Maximum Power Point Tracking

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Rasmussen, Claus Nygaard

    2014-01-01

    This paper presents the design of an L1 adaptive controller for maximum power point tracking (MPPT) of a small variable speed Wind Energy Conversion System (WECS). The proposed controller generates the optimal torque command for the vector controlled generator side converter (GSC) based on the wind...

  3. Robust performance of self-scheduled LPV control of doubly-fed induction generator in wind energy conversion systems

    NARCIS (Netherlands)

    Nguyen Tien, H.; Scherer, C. W.; Scherpen, J. M. A.

    2007-01-01

    This paper describes the design of a self-scheduled current controller for doubly-fed induction generators in wind energy conversion systems (WECS). The design is based on viewing the mechanical angular speed as an uncertain yet online measurable parameter and on subsuming the problem into the

  4. Steady-state analysis of the integrated natural gas and electric power system with bi-directional energy conversion

    DEFF Research Database (Denmark)

    Zeng, Qing; Fang, Jiakun; Li, Jinghua

    2016-01-01

    Nowadays, the electric power system and natural gas network are becoming increasingly coupled and interdependent. A harmonized integration of natural gas and electricity network with bi-directional energy conversion is expected to accommodate high penetration levels of renewables in terms of system...... flexibility. This work focuses on the steady-state analysis of the integrated natural gas and electric power system with bi-directional energy conversion. A unified energy flow formulation is developed to describe the nodal balance and branch flow in both systems and it is solved with the Newton...... series of wind power and power load are used to investigate the mitigation effect of the integrated energy system. At last, the effect of wind power and power demand on the output of Power to Gas (P2G) and gas-fired power generation (GPG) has also been investigated....

  5. Converse Piezoelectricity

    Science.gov (United States)

    Springborg, Michael; Kirtman, Bernard

    2013-03-01

    Piezoelectricity results from a coupling between responses to mechanical and electric perturbations and leads to changes in the polarization due to strain or stress or, alternatively, the occurrence of strain as a function of an applied external, electrostatic field (i.e., converse piezoelectricity). Theoretical studies of those properties for extended systems require accordingly that their dipole moment or polarization can be calculated. However, whereas the definition of the operator for the dipole moment for any finite system is trivial, it is only within the last 2 decades that the expressions for the equivalent operator in the independent-particle approximation for the infinite and periodic system have been presented. Here, we demonstrate that the so called branch dependence of the polarization for the infinite, periodic system is related to physical observables in contrast to what often is assumed. This is related to the finding that converse piezoelectric properties depend both on the surfaces of the samples of interest even for samples with size well above the thermodynamic limit. However, we shall demonstrate that these properties can be calculated without explicitly taking the surfaces into account. Both the foundations and results for real system shall be presented.

  6. Energy Conversion and Transmission Characteristics Analysis of Ice Storage Air Conditioning System Driven by Distributed Photovoltaic Energy System

    Directory of Open Access Journals (Sweden)

    Yongfeng Xu

    2016-01-01

    Full Text Available In order to reduce the investment and operation cost of distributed PV energy system, ice storage technology was introduced to substitute batteries for solar energy storage. Firstly, the ice storage air conditioning system (ISACS driven by distributed photovoltaic energy system (DPES was proposed and the feasibility studies have been investigated in this paper. And then, the theoretical model has been established and experimental work has been done to analyze the energy coupling and transferring characteristics in light-electricity-cold conversion process. In addition, the structure optimization analysis was investigated. Results revealed that energy losses were high in ice making process of ice slide maker with only 17.38% energy utilization efficiency and the energy efficiency and exergy efficiency of ISACS driven by DPES were 5.44% and 67.30%, respectively. So the immersed evaporator and cointegrated exchanger were adopted for higher energy utilization efficiency and better financial rewards in structure optimization. The COP and exergy efficiency of ice maker can be increased to 1.48 and 81.24%, respectively, after optimization and the energy utilization efficiency of ISACS driven by DPES could be improved 2.88 times. Moreover, ISACS has the out-of-the-box function of ordinary air conditioning system. In conclusion, ISACS driven by DPES will have good application prospects in tropical regions without power grid.

  7. The use of conversation mapping to frame key perceptual issues facing the general dental practice system in England.

    Science.gov (United States)

    Harris, R V; Dancer, J M; Smith, D; Campbell, S

    2009-06-01

    To demonstrate the use of a novel qualitative methodology namely conversation mapping, which can be used to capture differences in stakeholder perspectives and give a root definition of the problem in a complex policy area. The methodology is used in the context of the changes introduced in the English general dental practice system in April 2006, to investigate the key issues facing the system, as perceived by general dental practitioners (GDPs). From a broad trigger statement, three transformational statements were produced. Each participant recorded their contribution on a hard diagrammatic form as a 'map', with others responding with their own written comment, thus generating three conversation maps. Thematic analysis resulted in the generation of a preliminary model summarising key perceptual issues. The five emergent themes identified were: financing, dentists' wants/needs, the role of the public and patients, system goals and policy level decision making. Financing was identified as the core category to which all other categories were related. Conversation mapping, a methodology arising from a systems approach, can be used to develop a 'rich picture' of an oral health care system in order to define the core problem within this policy area. Findings suggest that GDPs identify the financing of the system as a fundamental source of problems within the general dental practice system. This appears to be at variance with the perception of policy makers, who report a more limited view, identifying the system of remuneration as the 'heart of the problem'.

  8. Tribromoisocyanuric acid/triphenylphosphine: a new system for conversion of alcohols into alkyl bromides

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Vitor S.C. de; Mattos, Marcio C.S. de, E-mail: mmattos@iq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Quimica. Departamento de Quimica Organica

    2014-05-15

    An efficient and facile method has been developed for the conversion of alcohols into alkyl bromides under neutral conditions using tribromoisocyanuric acid and triphenylphosphine (molar ratio 1.0:0.7:2.0, alcohol/tribromoisocyanuric acid/triphenylphosphine) in dichloromethane at room temperature. This method can be applied for the conversion of primary, secondary, benzilic and allylic alcohols, and their corresponding bromides are obtained in 67-82 % yield. Tertiary alcohols do not react under these conditions. (author)

  9. Pension Fund

    CERN Multimedia

    HR Department

    2009-01-01

    In line with the decisions concerning the new governance of the Pension Fund taken by the Council in June and September 2007, amendments to Section 2 "Structure and Functions" of the Rules of the Fund (Article I 2.08 – Composition of the Investment Committee and Article I 2.08b – Chairman of the Investment Committee) entered into force on 1st January 2009. These articles replace the provisions of the existing Regulations of the Investment Committee of the Pension Fund relating to the composition and chairman of the Investment Committee. Amendment No. 27 (PDF document) may be downloaded directly from the Pension Fund website: http://pensions.web.cern.ch/Pensions/statuts___rules.htm or obtained from the Administration of the Fund (Tel. 022 7672742, mailto:Barbara.Bordjah@cern.ch).

  10. Conversational sensemaking

    Science.gov (United States)

    Preece, Alun; Webberley, Will; Braines, Dave

    2015-05-01

    Recent advances in natural language question-answering systems and context-aware mobile apps create opportunities for improved sensemaking in a tactical setting. Users equipped with mobile devices act as both sensors (able to acquire information) and effectors (able to act in situ), operating alone or in collectives. The currently- dominant technical approaches follow either a pull model (e.g. Apple's Siri or IBM's Watson which respond to users' natural language queries) or a push model (e.g. Google's Now which sends notifications to a user based on their context). There is growing recognition that users need more flexible styles of conversational interaction, where they are able to freely ask or tell, be asked or told, seek explanations and clarifications. Ideally such conversations should involve a mix of human and machine agents, able to collaborate in collective sensemaking activities with as few barriers as possible. Desirable capabilities include adding new knowledge, collaboratively building models, invoking specific services, and drawing inferences. As a step towards this goal, we collect evidence from a number of recent pilot studies including natural experiments (e.g. situation awareness in the context of organised protests) and synthetic experiments (e.g. human and machine agents collaborating in information seeking and spot reporting). We identify some principles and areas of future research for "conversational sensemaking".

  11. Microbial community response to chlorine conversion in a chloraminated drinking water distribution system.

    Science.gov (United States)

    Wang, Hong; Proctor, Caitlin R; Edwards, Marc A; Pryor, Marsha; Santo Domingo, Jorge W; Ryu, Hodon; Camper, Anne K; Olson, Andrew; Pruden, Amy

    2014-09-16

    Temporary conversion to chlorine (i.e., "chlorine burn") is a common approach to controlling nitrification in chloraminated drinking water distribution systems, yet its effectiveness and mode(s) of action are not fully understood. This study characterized occurrence of nitrifying populations before, during and after a chlorine burn at 46 sites in a chloraminated distribution system with varying pipe materials and levels of observed nitrification. Quantitative polymerase chain reaction analysis of gene markers present in nitrifying populations indicated higher frequency of detection of ammonia oxidizing bacteria (AOB) (72% of samples) relative to ammonia oxidizing archaea (AOA) (28% of samples). Nitrospira nitrite oxidizing bacteria (NOB) were detected at 45% of samples, while presence of Nitrobacter NOB could not be confirmed at any of the samples. During the chlorine burn, the numbers of AOA, AOB, and Nitrospira greatly reduced (i.e., 0.8-2.4 log). However, rapid and continued regrowth of AOB and Nitrospira were observed along with nitrite production in the bulk water within four months after the chlorine burn, and nitrification outbreaks appeared to worsen 6-12 months later, even after adopting a twice annual burn program. Although high throughput sequencing of 16S rRNA genes revealed a distinct community shift and higher diversity index during the chlorine burn, it steadily returned towards a condition more similar to pre-burn than burn stage. Significant factors associated with nitrifier and microbial community composition included water age and sampling location type, but not pipe material. Overall, these results indicate that there is limited long-term effect of chlorine burns on nitrifying populations and the broader microbial community.

  12. Real time implementation and control validation of the wind energy conversion system

    Science.gov (United States)

    Sattar, Adnan

    The purpose of the thesis is to analyze dynamic and transient characteristics of wind energy conversion systems including the stability issues in real time environment using the Real Time Digital Simulator (RTDS). There are different power system simulation tools available in the market. Real time digital simulator (RTDS) is one of the powerful tools among those. RTDS simulator has a Graphical User Interface called RSCAD which contains detail component model library for both power system and control relevant analysis. The hardware is based upon the digital signal processors mounted in the racks. RTDS simulator has the advantage of interfacing the real world signals from the external devices, hence used to test the protection and control system equipments. Dynamic and transient characteristics of the fixed and variable speed wind turbine generating systems (WTGSs) are analyzed, in this thesis. Static Synchronous Compensator (STATCOM) as a flexible ac transmission system (FACTS) device is used to enhance the fault ride through (FRT) capability of the fixed speed wind farm. Two level voltage source converter based STATCOM is modeled in both VSC small time-step and VSC large time-step of RTDS. The simulation results of the RTDS model system are compared with the off-line EMTP software i.e. PSCAD/EMTDC. A new operational scheme for a MW class grid-connected variable speed wind turbine driven permanent magnet synchronous generator (VSWT-PMSG) is developed. VSWT-PMSG uses fully controlled frequency converters for the grid interfacing and thus have the ability to control the real and reactive powers simultaneously. Frequency converters are modeled in the VSC small time-step of the RTDS and three phase realistic grid is adopted with RSCAD simulation through the use of optical analogue digital converter (OADC) card of the RTDS. Steady state and LVRT characteristics are carried out to validate the proposed operational scheme. Simulation results show good agreement with real

  13. Conversational Dominance.

    Science.gov (United States)

    Esau, Helmut; Poth, Annette

    Details of conversational behavior can often not be interpreted until the social interaction, including the rights and obligations of the participants, their intent, the topic, etc., has been defined. This paper presents a model of conversation in which the conversational image a person presents in a given conversational situation is a function of…

  14. The evolution of the federal funding policies for the public health surveillance component of Brazil's Unified Health System (SUS

    Directory of Open Access Journals (Sweden)

    Vitor Laerte Pinto Junior

    2014-12-01

    Full Text Available Health surveillance (HS is one of the key components of the Brazilian Unified Health System (SUS. This article describes recent changes in health surveillance funding models and the role these changes have had in the reorganization and decentralization of health actions. Federal law no. 8.080 of 1990 defined health surveillance as a fundamental pillar of the SUS, and an exclusive fund with equitable distribution criteria was created in the Basic Operational Norm of 1996 to pay for health surveillance actions. This step facilitated the decentralization of health care at the municipal level, giving local authorities autonomy to plan and provide services. The Health Pact of 2006 and its regulation under federal decree No. 3252 in 2009 bolstered the processes of decentralization, regionalization and integration of health care. Further changes in the basic concepts of health surveillance around the world and in the funding policies negotiated by different spheres of government in Brazil have been catalysts for the process of HS institutionalization in recent years.

  15. Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs

    Energy Technology Data Exchange (ETDEWEB)

    Yoder, G.L.

    2005-10-03

    This report documents the work performed during the first phase of the National Aeronautics and Space Administration (NASA), National Research Announcement (NRA) Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs. The document includes an optimization of both 100-kW{sub e} and 250-kW{sub e} (at the propulsion unit) Rankine cycle power conversion systems. In order to perform the mass optimization of these systems, several parametric evaluations of different design options were investigated. These options included feed and reheat, vapor superheat levels entering the turbine, three different material types, and multiple heat rejection system designs. The overall masses of these Nb-1%Zr systems are approximately 3100 kg and 6300 kg for the 100- kW{sub e} and 250-kW{sub e} systems, respectively, each with two totally redundant power conversion units, including the mass of the single reactor and shield. Initial conceptual designs for each of the components were developed in order to estimate component masses. In addition, an overall system concept was presented that was designed to fit within the launch envelope of a heavy lift vehicle. A technology development plan is presented in the report that describes the major efforts that are required to reach a technology readiness level of 6. A 10-year development plan was proposed.

  16. The creation of management systems for funding priorities in wastewater project in rural communities in the Islamic Republic of Iran.

    Science.gov (United States)

    Farrokhi, M; Hajrasoliha, M; Meemari, G; Fahiminia, M; Talebi, M; Kohansal, M

    2008-01-01

    For sustainable development an integrated cost-effective approach focused on the goal of health and environmental protection is necessary. In Iran more than 22 million people live in rural communities. A little more than 92% of the rural population in Iran have access to safe drinking water supply, but only less than 0.2% have sanitary wastewater disposal system. Groundwater is the main resource of water supply in rural communities in Iran and contaminated or untreated groundwater can be the major reason for waterborne diseases outbreak and wastewater discharge is the main cause of groundwater contamination. In new strategy in Iran's wastewater company, the importance of wastewater treatment is equal to water treatment in rural communities and the main goal in this section is providing sanitary wastewater disposal system for 8% of rural areas until 2010 and 30% until 2020. One of the most important limitations for establishment of wastewater disposal system is the limitation of governmental funds. For this reason, a national program was performed for ranking of rural communities with the goal of improving the funding effectiveness in wastewater management in rural communities. Many important criteria were considered for determination of priorities, these criteria include: population, population density, water consumption and wastewater generation, wastes disposal systems at present, environmental and health risks, agricultural and industrial wastewater, social conditions specially public participation, investment simplicity and type of living (seasonal or permanent). For collection of information about rural community, according to the criteria, a questionnaire was designed with 40 quantified questions. Questionnaires completed for all rural areas with more than 400 people population (more than 77% of rural population of the country). Completed questionnaires were analyzed with specific software for ranking of villages according to above mentioned criteria. Right

  17. Microencapsulated Phase Change Materials in Solar-Thermal Conversion Systems: Understanding Geometry-Dependent Heating Efficiency and System Reliability.

    Science.gov (United States)

    Zheng, Zhaoliang; Chang, Zhuo; Xu, Guang-Kui; McBride, Fiona; Ho, Alexandra; Zhuola, Zhuola; Michailidis, Marios; Li, Wei; Raval, Rasmita; Akhtar, Riaz; Shchukin, Dmitry

    2017-01-24

    The performance of solar-thermal conversion systems can be improved by incorporation of nanocarbon-stabilized microencapsulated phase change materials (MPCMs). The geometry of MPCMs in the microcapsules plays an important role for improving their heating efficiency and reliability. Yet few efforts have been made to critically examine the formation mechanism of different geometries and their effect on MPCMs-shell interaction. Herein, through changing the cooling rate of original emulsions, we acquire MPCMs within the nanocarbon microcapsules with a hollow structure of MPCMs (h-MPCMs) or solid PCM core particles (s-MPCMs). X-ray photoelectron spectroscopy and atomic force microscopy reveals that the capsule shell of the h-MPCMs is enriched with nanocarbons and has a greater MPCMs-shell interaction compared to s-MPCMs. This results in the h-MPCMs being more stable and having greater heat diffusivity within and above the phase transition range than the s-MPCMs do. The geometry-dependent heating efficiency and system stability may have important and general implications for the fundamental understanding of microencapsulation and wider breadth of heating generating systems.

  18. Exploratory analysis of real personal emergency response call conversations: considerations for personal emergency response spoken dialogue systems.

    Science.gov (United States)

    Young, Victoria; Rochon, Elizabeth; Mihailidis, Alex

    2016-11-14

    The purpose of this study was to derive data from real, recorded, personal emergency response call conversations to help improve the artificial intelligence and decision making capability of a spoken dialogue system in a smart personal emergency response system. The main study objectives were to: develop a model of personal emergency response; determine categories for the model's features; identify and calculate measures from call conversations (verbal ability, conversational structure, timing); and examine conversational patterns and relationships between measures and model features applicable for improving the system's ability to automatically identify call model categories and predict a target response. This study was exploratory and used mixed methods. Personal emergency response calls were pre-classified according to call model categories identified qualitatively from response call transcripts. The relationships between six verbal ability measures, three conversational structure measures, two timing measures and three independent factors: caller type, risk level, and speaker type, were examined statistically. Emergency medical response services were the preferred response for the majority of medium and high risk calls for both caller types. Older adult callers mainly requested non-emergency medical service responders during medium risk situations. By measuring the number of spoken words-per-minute and turn-length-in-words for the first spoken utterance of a call, older adult and care provider callers could be identified with moderate accuracy. Average call taker response time was calculated using the number-of-speaker-turns and time-in-seconds measures. Care providers and older adults used different conversational strategies when responding to call takers. The words 'ambulance' and 'paramedic' may hold different latent connotations for different callers. The data derived from the real personal emergency response recordings may help a spoken dialogue system

  19. The adhesive system and root canal region do not influence the degree of conversion of dual resin cement

    Science.gov (United States)

    PEREIRA, Priscilla Cristoforides; de MELO, Renata Marques; CHAVES, Carolina; GALHANO, Graziela A. P.; BOTTINO, Marco Antonio; BALDUCCI, Ivan

    2010-01-01

    Objectives The aim of this study was to evaluate the influence of two adhesive systems and the post space region on the degree of conversion of dual resin cement and its bond strength to root dentin. Material and Methods One three-step etch-andrinse (All-bond 2, Bisco) and another one-step self-etch (Xeno III, Dentsply) adhesive systems were applied on 20 (n=10) crownless bovine incisors, at 12-mm-deep post space preparation, and a fiber post (DT Light Post, Bisco) was cemented using a dual cure resin cement (Duo-Link, Bisco). Three transverse sections (3 mm) were obtained, being one from each study region (cervical, middle and apical). The degree of conversion of the dual cure resin cement was determined by a micro-Raman spectrometer. The data (%) were submitted to repeated-measures analysis of variance and Tukey's test (p<0.05). Results For both groups, the degree of conversion means (%) (All bond 2cervical = 69.3; All bond 2middle = 55.1; All bond 2apical= 56; Xeno IIIcervical = 68.7; Xeno IIImiddle = 68.8; Xeno IIIapical = 54.3) were not significantly different along the post space regions (p<0.05). Conclusion Neither the adhesive nor the post space region influenced the degree of conversion of the cement layer. PMID:21085803

  20. The adhesive system and root canal region do not influence the degree of conversion of dual resin cement

    Directory of Open Access Journals (Sweden)

    Priscilla Cristoforides Pereira

    2010-10-01

    Full Text Available OBJECTIVES: The aim of this study was to evaluate the influence of two adhesive systems and the post space region on the degree of conversion of dual resin cement and its bond strength to root dentin. MATERIAL AND METHODS: One three-step etch-and-rinse (All-bond 2, Bisco and another one-step self-etch (Xeno III, Dentsply adhesive systems were applied on 20 (n=10 crownless bovine incisors, at 12-mm-deep post space preparation, and a fiber post (FRC Postec, Ivoclar was cemented using a dual cure resin cement (Duo-Link, Bisco. Three transverse sections (3 mm were obtained, being one from each study region (cervical, middle and apical. The degree of conversion of the dual cure resin cement was determined by a micro-Raman spectrometer. The data (% were submitted to repeated-measures analysis of variance and Tukey's test (p<0.05. RESULTS: For both groups, the degree of conversion means (% (All bond 2cervical = 69.3; All bond 2middle = 55.1; All bond 2apical= 56; Xeno III cervical = 68.7; Xeno IIImiddle = 68.8; Xeno III apical = 54.3 were not significantly different along the post space regions (p<0.05. CONCLUSION: Neither the adhesive nor the post space region influenced the degree of conversion of the cement layer.

  1. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  2. Gas Turbine Energy Conversion Systems for Nuclear Power Plants Applicable to LiFTR Liquid Fluoride Thorium Reactor Technology

    Science.gov (United States)

    Juhasz, Albert J.

    2014-01-01

    This panel plans to cover thermal energy and electric power production issues facing our nation and the world over the next decades, with relevant technologies ranging from near term to mid-and far term.Although the main focus will be on ground based plants to provide baseload electric power, energy conversion systems (ECS) for space are also included, with solar- or nuclear energy sources for output power levels ranging tens of Watts to kilo-Watts for unmanned spacecraft, and eventual mega-Watts for lunar outposts and planetary surface colonies. Implications of these technologies on future terrestrial energy systems, combined with advanced fracking, are touched upon.Thorium based reactors, and nuclear fusion along with suitable gas turbine energy conversion systems (ECS) will also be considered by the panelists. The characteristics of the above mentioned ECS will be described, both in terms of their overall energy utilization effectiveness and also with regard to climactic effects due to exhaust emissions.

  3. Funding innovation

    CERN Multimedia

    Marina Giampietro

    2012-01-01

    For the first time, six knowledge and technology transfer activities are set to benefit from a dedicated fund made available by the Knowledge Transfer group. This initiative cements CERN’s commitment to sharing its technological knowledge and expertise with society.   GEM detectors for flame detection and early earthquake prediction, radio-frequency absorbers for energy recovery, and exotic radioisotopes for medical applications are among the projects funded by the recently introduced KT Fund. “CERN’s scientific programme generates a considerable amount of intellectual property, a natural driver for innovation,” explains Giovanni Anelli, Head of the Knowledge Transfer Group. “Very often, though, financial support is needed to bring the newly-born technologies a step further and make them ready for transfer to other research institutes or to companies.” This is where the KT fund comes into play. It provides vital support in the early sta...

  4. Pension Fund

    CERN Document Server

    HR Department

    2009-01-01

    In line with the decisions taken by the Council in June and September 2007 concerning the new governance of the Pension Fund, amendments to Section 2 «Structure and Functions» of the Rules of the Fund entered into force on 1st January 2009 (Article I 2.08 – Composition of the Investment Committee and Article I 2.08bis – Chairman of the Investment Committee). Amendment n°27 may be downloaded (PDF document) directly from the Pension Fund website: http://pensions.web.cern.ch/Pensions/statuts___rules.htm or obtained from the Administration of the Fund (Tel. 022 767 2742, mailto:Barbara.Bordjah@cern.ch).

  5. Development of a system for characterizing biomass quality of lignocellulosic feedstocks for biochemical conversion

    Science.gov (United States)

    Murphy, Patrick Thomas

    The purpose of this research was twofold: (i) to develop a system for screening lignocellulosic biomass feedstocks for biochemical conversion to biofuels and (ii) to evaluate brown midrib corn stover as feedstock for ethanol production. In the first study (Chapter 2), we investigated the potential of corn stover from bm1-4 hybrids for increased ethanol production and reduced pretreatment intensity compared to corn stover from the isogenic normal hybrid. Corn stover from hybrid W64A X A619 and respective isogenic bm hybrids was pretreated by aqueous ammonia steeping using ammonium hydroxide concentrations from 0 to 30%, by weight, and the resulting residues underwent simultaneous saccharification and cofermentation (SSCF) to ethanol. Dry matter (DM) digested by SSCF increased with increasing ammonium hydroxide concentration across all genotypes (P>0.0001) from 277 g kg-1 DM in the control to 439 g kg-1 DM in the 30% ammonium hydroxide pretreatment. The bm corn stover materials averaged 373 g kg-1 DM of DM digested by SSCF compared with 335 g kg-1 DM for the normal corn stover (Pcorn stover, (ii) the lowest initial cell-wall carbohydrate concentration, (iii) the lowest dry matter remaining after pretreatment, and (iv) the highest amount of monosaccharides released during enzymatic hydrolysis. However, bm corn stover did not reduce the severity of aqueous ammonia steeping pretreatment needed to maximize DM hydrolysis during SSCF compared with normal corn stover. In the remaining studies (Chapters 3 thru 5), a system for analyzing the quality of lignocellulosic biomass feedstocks for biochemical conversion to biofuels (i.e., pretreatment, enzymatic hydrolysis, and fermentation) was developed. To accomplish this, a carbohydrate availability model was developed to characterize feedstock quality. The model partitions carbohydrates within a feedstock material into fractions based on their availability to be converted to fermentable sugars, including non

  6. Characterisation of Systems for Raman-Assisted High-Speed Wavelength Conversion

    DEFF Research Database (Denmark)

    Galili, Michael; Oxenløwe, Leif Katsuo; Zibar, Darko

    2005-01-01

    Raman-assisted wavelength conversion for ultra-high speed data is characterised in approaches: a novel scheme based on cross-phase modulation using specially designed notch filters and a 160 Gb/s experiment based on self-phase modulation......Raman-assisted wavelength conversion for ultra-high speed data is characterised in approaches: a novel scheme based on cross-phase modulation using specially designed notch filters and a 160 Gb/s experiment based on self-phase modulation...

  7. Hydrothermal conversion of FAU zeolite into RUT zeolite in TMAOH system

    OpenAIRE

    Jon, Hery; Takahashi, Shoutarou; Sasaki, Hitoshi; Oumi, Yasunori; Sano, Tsuneji

    2008-01-01

    The highly crystalline and pure RUT (RUB-10) zeolite could be obtained from the hydrothermal conversion of FAU zeolite used as a crystalline Si/Al source in tetramethylammonium hydroxide (TMAOH) media. As compared to amorphous silica/Al(OH)3 and amorphous silica/γ-Al2O3 sources, the crystallization rate for the formation of RUT zeolite was clearly faster when FAU zeolite was employed as the Si/Al source. Moreover, it was found that the hydrothermal conversion of FAU zeolite into RUT zeolite d...

  8. Pension Fund

    CERN Multimedia

    HR Department

    2008-01-01

    The Pension Fund Governing Board (PFGB) held two meetings over the summer, the first on 9 June and the second on 1st September. The agendas of the two meetings had several items in common, including progress reports on the work of the four working groups. Group 1, which is responsible for the revision of Chapter I, Section 2 of the Rules of the Fund, has made good progress but will need more time to complete its terms of reference in view of the number and complexity of the articles to be amended. In parallel, the Group has approved a code of conduct for the Pension Fund, which is based, in particular, on the new charter introduced for Swiss pension funds by the Swiss Association of Provident Institutions (ASIP) and the CFA (Chartered Financial Analyst) code of ethics applicable to members of pension fund bodies. The PFGB took note that the Group had also been working on the rules relating to the status of the personnel of the Fund and the composition of the Investment Committee. The work of Group 2, responsi...

  9. Bulk single crystal ternary substrates for a thermophotovoltaic energy conversion system

    Science.gov (United States)

    Charache, Greg W.; Baldasaro, Paul F.; Nichols, Greg J.

    1998-01-01

    A thermophotovoltaic energy conversion device and a method for making the device. The device includes a substrate formed from a bulk single crystal material having a bandgap (E.sub.g) of 0.4 eVternary or quaternary III-V semiconductor active layers.

  10. Identification of an Enzyme System for Daidzein-to-Equol Conversion in Slackia sp. Strain NATTS

    Science.gov (United States)

    Moriyama, Kaoru; Nomoto, Koji; Akaza, Hideyuki

    2012-01-01

    An Escherichia coli library comprising 8,424 strains incorporating gene fragments of the equol-producing bacterium Slackia sp. strain NATTS was constructed and screened for E. coli strains having daidzein- and dihydrodaidzein (DHD)- metabolizing activity. We obtained 3 clones that functioned to convert daidzein to DHD and 2 clones that converted DHD to equol. We then sequenced the gene fragments inserted into plasmids contained by these 5 clones. All of the gene fragments were contiguous, encoding three open reading frames (ORF-1, -2, and -3). Analysis of E. coli strains containing an expression vector incorporating one of the orf-1, -2, or -3 genes revealed that (i) the protein encoded by orf-1 was involved in the conversion of cis/trans-tetrahydrodaidzein (cis/trans-THD) to equol, (ii) the protein encoded by orf-2 was involved in the conversion of DHD to cis/trans-THD, and (iii) the protein encoded by orf-3 was involved in the conversion of daidzein to DHD. ORF-1 had a primary amino acid structure similar to that of succinate dehydrogenase. ORF-2 was presumed to be an enzyme belonging to the short-chain dehydrogenase/reductase superfamily. ORF-3 was predicted to have 42% identity to the daidzein reductase of Lactococcus strain 20-92 and belonged to the NADH:flavin oxidoreductase family. These findings showed that the daidzein-to-equol conversion reaction in the Slackia sp. NATTS strain proceeds by the action of these three enzymes. PMID:22179235

  11. ANALOG-TO-DIGITAL CONVERSION OF SIGNALS WITH ANGULAR MANIPULATION FOR SOFTWARE DEFINED RADIO SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Y. Tsvetkov

    2016-05-01

    Full Text Available The paper deals with the search of ways for speeding up and accuracy increase of conversion of modern analog-to-digital converters. The main shortcomings interfering a solution of this task including the field of optoelectronic analog-to-digital converters are provided. The proposed solution gives the chance to increase high-speed performance of analog-to-digital converters on the basis of holographic interferometry principles without reducing their accuracy of conversion. The optical scheme of interferential and holographic method of analog-to-digital conversion and results of its mathematical modeling are provided. Some recommendations about hardware implementation of this analog data digitizer are formulated. The physical principles and approaches to a choice of the converter structural elements are explained. An example of forming the functional scheme of a decoder for a luminous flux intensity in terms of registration of analog-to-digital converter is reviewed. The practical importance of the provided method consists in possibility of creation of analog-to-digital converters with high-speed performance about 600 MHz and with an accuracy of conversion up to 12 bits.

  12. Evaluation of Switch Currents in Nine-Switch Energy Conversion Systems

    DEFF Research Database (Denmark)

    Loh, Poh Chiang; Bahman, Amir Sajjad; Qin, Zian

    2013-01-01

    since been shown to experience a higher voltage stress, which can be lowered in some cases. A corresponding evaluation of its current stress is however lacking, and is hence addressed now by computing its switch currents when used for ac-ac, ac-dc, dc-ac and dc-dc energy conversions. Relevant...

  13. Evaluation of current stresses in nine-switch energy conversion systems

    DEFF Research Database (Denmark)

    Qin, Zian; Loh, Poh Chiang; Bahman, Amir Sajjad

    2014-01-01

    since been shown to experience a higher voltage stress, which can be lowered in some cases. A corresponding evaluation of its current stress is however lacking, and is hence addressed now by computing its switch currents when used for ac-ac, ac-dc, dc-ac and dc-dc energy conversions. Relevant...

  14. Manipulating Stress and Cognitive Load in Conversational Interactions with a Multimodal System for Crisis Management Support

    NARCIS (Netherlands)

    Niculescu, A.I.; Cao, Y.; Esposito, A.; Campbell, N.; Vogel, C.; Hussain, A.; Nijholt, Antinus

    2010-01-01

    The quality assessment of multimodal conversational interfaces is influenced by many factors. Stress and cognitive load are two of most important. In the literature, these two factors are considered as being related and accordingly summarized under the single concept of ‘cognitive demand’. However,

  15. Loneliness and the social monitoring system: Emotion recognition and eye gaze in a real-life conversation.

    Science.gov (United States)

    Lodder, Gerine M A; Scholte, Ron H J; Goossens, Luc; Engels, Rutger C M E; Verhagen, Maaike

    2016-02-01

    Based on the belongingness regulation theory (Gardner et al., 2005, Pers. Soc. Psychol. Bull., 31, 1549), this study focuses on the relationship between loneliness and social monitoring. Specifically, we examined whether loneliness relates to performance on three emotion recognition tasks and whether lonely individuals show increased gazing towards their conversation partner's faces in a real-life conversation. Study 1 examined 170 college students (Mage = 19.26; SD = 1.21) who completed an emotion recognition task with dynamic stimuli (morph task) and a micro(-emotion) expression recognition task. Study 2 examined 130 college students (Mage = 19.33; SD = 2.00) who completed the Reading the Mind in the Eyes Test and who had a conversation with an unfamiliar peer while their gaze direction was videotaped. In both studies, loneliness was measured using the UCLA Loneliness Scale version 3 (Russell, 1996, J. Pers. Assess., 66, 20). The results showed that loneliness was unrelated to emotion recognition on all emotion recognition tasks, but that it was related to increased gaze towards their conversation partner's faces. Implications for the belongingness regulation system of lonely individuals are discussed. © 2015 The British Psychological Society.

  16. Simulating the Conversion of Rural Settlements to Town Land Based on Multi-Agent Systems and Cellular Automata

    Science.gov (United States)

    Liu, Yaolin; Kong, Xuesong; Liu, Yanfang; Chen, Yiyun

    2013-01-01

    Rapid urbanization in China has triggered the conversion of land from rural to urban use, particularly the conversion of rural settlements to town land. This conversion is the result of the joint effects of the geographic environment and agents involving the government, investors, and farmers. To understand the dynamic interaction dominated by agents and to predict the future landscape of town expansion, a small town land-planning model is proposed based on the integration of multi-agent systems (MAS) and cellular automata (CA). The MAS-CA model links the decision-making behaviors of agents with the neighbor effect of CA. The interaction rules are projected by analyzing the preference conflicts among agents. To better illustrate the effects of the geographic environment, neighborhood, and agent behavior, a comparative analysis between the CA and MAS-CA models in three different towns is presented, revealing interesting patterns in terms of quantity, spatial characteristics, and the coordinating process. The simulation of rural settlements conversion to town land through modeling agent decision and human-environment interaction is very useful for understanding the mechanisms of rural-urban land-use change in developing countries. This process can assist town planners in formulating appropriate development plans. PMID:24244472

  17. What are Middle School Students Talking About During Clicker Questions? Characterizing Small-Group Conversations Mediated by Classroom Response Systems

    Science.gov (United States)

    Barth-Cohen, Lauren A.; Smith, Michelle K.; Capps, Daniel K.; Lewin, Justin D.; Shemwell, Jonathan T.; Stetzer, MacKenzie R.

    2016-02-01

    There is a growing interest in using classroom response systems or clickers in science classrooms at both the university and K-12 levels. Typically, when instructors use this technology, students are asked to answer and discuss clicker questions with their peers. The existing literature on using clickers at the K-12 level has largely focused on the efficacy of clicker implementation, with few studies investigating collaboration and discourse among students. To expand on this work, we investigated the question: Does clicker use promote productive peer discussion among middle school science students? Specifically, we collected data from middle school students in a physical science course. Students were asked to answer a clicker question individually, discuss the question with their peers, answer the same question again, and then subsequently answer a new matched-pair question individually. We audio recorded the peer conversations to characterize the nature of the student discourse. To analyze these conversations, we used a grounded analysis approach and drew on literature about collaborative knowledge co-construction. The analysis of the conversations revealed that middle school students talked about science content and collaboratively discussed ideas. Furthermore, the majority of conversations, both ones that positively and negatively impacted student performance, contained evidence of collaborative knowledge co-construction.

  18. Enhanced Capability of Photoelectrochemical CO2 Conversion System Using an AlGaN/GaN Photoelectrode

    Science.gov (United States)

    Deguchi, Masahiro; Yotsuhashi, Satoshi; Hashiba, Hiroshi; Yamada, Yuka; Ohkawa, Kazuhiro

    2013-08-01

    We report significantly improved photosynthesis system based on AlGaN/GaN photochemical process. The resultant energy conversion efficiency is 0.13% which is the same level as that of real plants. The capability of this system is enhanced by high cathode potential due to the reduction of energy loss while utilizing the piezoelectric effect in the AlGaN/GaN heterostructure. The Faradaic efficiency of the CO2 conversion to organic materials is enhanced, accompanied by an increment in photocurrent by modification of the AlGaN/GaN photoelectrode structure and electrolytes. Furthermore, reaction products such as C2H4 and C2H5OH are generated by light illumination alone.

  19. Photoactivation studies of zinc porphyrin-myoglobin system and its application for light-chemical energy conversion.

    Science.gov (United States)

    Chang, Chin-Hao; Hu, Yi-Ting; Lo, Chen-Fu; Luo, Liyang; Lin, Hung-Ming; Chang, Cheng-Hsiang; Lin, Ching-Yao; Diau, Eric Wei-Guang; Wu, Tung-Kung

    2011-01-01

    An artificial zinc porphyrin-myoglobin-based photo-chemical energy conversion system, consisting of ZnPP-Mb or ZnPE(1)-Mb as a photosensitizer, NADP(+) as an electron acceptor, and triethanolamine as an electron donor, has been constructed to mimic photosystem I. The photoirradiated product is able to reduce a single-electron acceptor protein cytochrome c, but cannot catalyze the two-electron reduction of acetaldehyde by alcohol dehydrogenase, thus demonstrating a single electron transfer mechanism. Furthermore, the artificial system can bifunctionally promote oxidoredox reactions, depending on the presence or absence of a sacrificial electron donor, thus suggesting its potential application in electrochemical regeneration steps involved in chemical transformation and/or energy conversion.

  20. 2D materials. Graphene, related two-dimensional crystals, and hybrid systems for energy conversion and storage.

    Science.gov (United States)

    Bonaccorso, Francesco; Colombo, Luigi; Yu, Guihua; Stoller, Meryl; Tozzini, Valentina; Ferrari, Andrea C; Ruoff, Rodney S; Pellegrini, Vittorio

    2015-01-02

    Graphene and related two-dimensional crystals and hybrid systems showcase several key properties that can address emerging energy needs, in particular for the ever growing market of portable and wearable energy conversion and storage devices. Graphene's flexibility, large surface area, and chemical stability, combined with its excellent electrical and thermal conductivity, make it promising as a catalyst in fuel and dye-sensitized solar cells. Chemically functionalized graphene can also improve storage and diffusion of ionic species and electric charge in batteries and supercapacitors. Two-dimensional crystals provide optoelectronic and photocatalytic properties complementing those of graphene, enabling the realization of ultrathin-film photovoltaic devices or systems for hydrogen production. Here, we review the use of graphene and related materials for energy conversion and storage, outlining the roadmap for future applications. Copyright © 2015, American Association for the Advancement of Science.

  1. Bayesian Zero-Failure (BAZE) reliability demonstration testing procedure and its application to a Rankine dynamic radioisotope power conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Martz, H.F. Jr.; Waller, R.A.

    1976-07-01

    A Bayesian Zero-Failure (BAZE) reliability demonstration testing procedure is developed. The procedure may be used to verify component failure rates associated with both real-time dependent and cycle-dependent chance failure mechanisms. A constant falure-rate model with a gamma prior distribution is assumed. The procedure is used to obtain sample test plans for components of a proposed Rankine power conversion system.

  2. Modelling of a 5-kW wind energy conversion system with induction generator and comparison with experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Surgevil, T.; Akpinar, E. [Dokuz Surgevil University, Izmir (Turkey). Dept. of Electrical and Electronics Engineering

    2005-05-01

    A 5-kW wind energy conversion system (WECS) having induction generator is designed and implemented. The induction machine is connected to the power system through PWM inverter and PWM rectifier. Two digital PI controllers are used, one of them is for regulating dc link voltage and the other is for speed control of induction machine. The whole system is governed by a single fixed-point digital signal-processing unit (DSP). A detailed simulation program is prepared by using Matlab facilities in order to predict the performance of the controllers before implementation. (author)

  3. Pension Fund

    CERN Multimedia

    HR Department

    2008-01-01

    The PFGB held two meetings over the summer, the first on 9 June and the second on 1st September. The agendas of the two meetings had several items in common, including progress reports on the work of the four working groups. Group 1, which is responsible for the revision of Chapter I, Section 2 of the Rules of the Fund, has made good progress but will need more time to complete its terms of reference in view of the number and complexity of the articles to be amended. In parallel, the Group has approved a code of conduct for the Pension Fund, which is based, in particular, on the new charter introduced for Swiss pension funds by the Swiss Association of Provident Institutions (ASIP) and the CFA (Chartered Financial Analyst) code of ethics applicable to members of pension fund bodies. The PFGB took note that the Group had also been working on the rules relating to the status of the personnel of the Fund and the composition of the Investment Committee. The work of Group 2, resp...

  4. PENSION FUND

    CERN Multimedia

    1999-01-01

    The Governing Board of the Pension Fund held its first three meetings of the year on 2 February, 2 March and 13 April.At the first of these meetings the Board first heard a presentation by Mrs H. Richmond of JP Morgan on the results of the currency overlay programme applied to the Fund's assets. Thanks to the policy pursued by this company, volatility, i.e. portfolio risk for assets denominated in currencies other than the Swiss franc, has been reduced. However, despite the fact that JP Morgan has considerable expertise in this field, no gain has been achieved over the past year. The Governing Board heard a report by the Investment Committee Chairman G. Maurin on the meetings of 21-22 and 28 January at which the Pension Fund's various fund managers had been interviewed on their results. Decisions were taken on benchmarks aimed at optimising management and on the terms of reference of the Internal Management Unit. It was also decided to place two fund managers on a watching list and to request them to make eve...

  5. Pension Fund

    CERN Multimedia

    2003-01-01

    All members and beneficiaries of the Pension Fund are invited to attend the Annual General Asssembly to be held in the CERN Auditorium on Wednesday 8 October 2003 at 14.30 hrs The Agenda comprises: 1. Opening RemarksJ. Bezemer 2. Annual Report 2002: Presentation and results Copies of the Report are available from divisional secretariats. C. Cuénoud 3. Overview of the present situation with regard to pension funds C. Cuénoud 4. Performance of the Fund since the year 2000 and aspects of the ongoing asset/liability modelling exercise G. Maurin 5. Questions from members and beneficiariesPersons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund. 6. Conclusions J. Bezemer As usual, participants are invited to drinks after the assembly. NB The minutes of the 2002 General Assembly are available from the Administration of the Fund tel.(+4122)767 27 42; e-mail Sophia.Revol@cern.ch)

  6. Computers and conversation

    CERN Document Server

    Luff, Paul; Gilbert, Nigel G

    1986-01-01

    In the past few years a branch of sociology, conversation analysis, has begun to have a significant impact on the design of human*b1computer interaction (HCI). The investigation of human*b1human dialogue has emerged as a fruitful foundation for interactive system design.****This book includes eleven original chapters by leading researchers who are applying conversation analysis to HCI. The fundamentals of conversation analysis are outlined, a number of systems are described, and a critical view of their value for HCI is offered.****Computers and Conversation will be of interest to all concerne

  7. PEPFAR Investments In Governance And Health Systems Were One-Fifth Of Countries' Budgeted Funds, 2004-14.

    Science.gov (United States)

    Moucheraud, Corrina; Sparkes, Susan; Nakamura, Yoriko; Gage, Anna; Atun, Rifat; Bossert, Thomas J

    2016-05-01

    Launched in 2003, the US President's Emergency Plan for AIDS Relief (PEPFAR) is the largest disease-focused assistance program in the world. We analyzed PEPFAR budgets for governance and systems for the period 2004-14 to ascertain whether PEPFAR's stated emphasis on strengthening health systems has been manifested financially. The main outcome variable in our analysis, the first of its kind using these data, was the share of PEPFAR's total annual budget for a country that was designated for governance and systems. The share of planned PEPFAR funding for governance and systems increased from 14.9 percent, on average, in 2004 to 27.5 percent in 2013, but it declined in 2014 to 20.8 percent. This study shows that the size of a country's PEPFAR budget was negatively associated with the share allocated for governance and systems (compared with other budget program areas); it also shows that there was no significant relationship between budgets for governance and systems and HIV prevalence. It is crucial for the global health policy community to better understand how such investments are allocated and used for health systems strengthening. Project HOPE—The People-to-People Health Foundation, Inc.

  8. Performance-based financing with GAVI health system strengthening funding in rural Cambodia: a brief assessment of the impact.

    Science.gov (United States)

    Matsuoka, Sadatoshi; Obara, Hiromi; Nagai, Mari; Murakami, Hitoshi; Chan Lon, Rasmey

    2014-07-01

    Though Cambodia made impressive gains in immunization coverage between the years 2000 and 2005, it recognized several health system challenges to greater coverage of immunization and sustainability. The Global Alliance for Vaccines and Immunization (GAVI) opened a Health System Strengthening (HSS) funding window in 2006. To address the health system challenges, Cambodia has been receiving the GAVI HSS fund since October 2007. The major component of the support is performance-based financing (PBF) for maternal, neonatal and child health (MNCH) services. To examine the impact of the PBF scheme on MNCH services and administrative management in rural Cambodia. Quantitative and qualitative studies were conducted in Kroch Chhmar Operational District (OD), Cambodia. Quantitative analyses were conducted on the trends of the numbers of MNCH services. A brief analysis was conducted using qualitative data. After the commencement of the PBF support, the volume of MNCH services was significantly boosted. In addition, strengthened financial and operational management was observed in the study area. However, the quality of the MNCH services was not ensured. Technical assistance, rather than the PBF scheme, was perceived by stakeholders to play a vital role in increasing the quality of the services. To improve the quality of the health services provided, it is better to include indicators on the quality of care in the PBF scheme. Mutual co-operation between PBF models and technical assistance may ensure better service quality while boosting the quantity. A robust but feasible data validation mechanism should be in place, as a PBF could incentivize inaccurate reporting. The capacity for financial management should be strengthened in PBF recipient ODs. To address the broader aspects of MNCH, a balanced input of resources and strengthening of all six building blocks of a health system are necessary. Published by Oxford University Press in association with The London School of Hygiene

  9. Pension Fund

    CERN Multimedia

    2003-01-01

    Amendment No 19 to the Rules and Regulations of the Pension Fund has just been published and can be obtained from Divisional secretariats or, in the case of pensioners, directly from the Administration of the Fund (tel. 767-91 94/27 38), bldg 5, 1-030. This Amendment, which entered into force on 1.1.2003, concerns 1) the fixed sums and allowances adjusted at same date (Annex B) and 2) the articles which have been amended, in accordance with the Finance Committee's decision, regarding voting rules of the Governing Board and the role and composition of the Investment Committee.

  10. Dentin bond strength and degree of conversion evaluation of experimental self-etch adhesive systems

    OpenAIRE

    Yazdi, Fatemeh Maleknejad; Moosavi, Horieh; Atai,Mohammad; Zeynali, Mahsa

    2015-01-01

    Background The aim of this study was to investigate the effect of different concentrations of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) monomer in one-step self-etch experimental adhesives on dentinal microshear bond strength (?SBS), their degree of conversion and bonded micro structure. Material and Methods Composite resin cylinders (Clearfil AP-X) were bonded on human sound molar dentinal surfaces by using five experimental one-step self-etching adhesives (1-SEAs) containing 0% ...

  11. Dentin bond strength and degree of conversion evaluation of experimental self-etch adhesive systems.

    Science.gov (United States)

    Yazdi, Fatemeh-Maleknejad; Moosavi, Horieh; Atai, Mohammad; Zeynali, Mahsa

    2015-04-01

    The aim of this study was to investigate the effect of different concentrations of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) monomer in one-step self-etch experimental adhesives on dentinal microshear bond strength (µSBS), their degree of conversion and bonded micro structure. Composite resin cylinders (Clearfil AP-X) were bonded on human sound molar dentinal surfaces by using five experimental one-step self-etching adhesives (1-SEAs) containing 0% (E0), 5% (E5), 10% (E10), 15% (E15), 20% (E20) (by weight) 10-MDP monomer and Clearfil S3 Bond (CS3) as a control. After 24 hours, microshear bond strength was tested. The degree of conversion was also measured using Fourier transform infrared spectroscopy. Interfacial ultrastructure was observed under a scanning electron microscope in all the groups. A higher microshear bond strength was observed with adhesives containing 10% and 15% 10-MDP in comparison to study groups (PSelf-etch adhesives, 10-MDP, bond strength, degree of conversion.

  12. Dentin bond strength and degree of conversion evaluation of experimental self-etch adhesive systems

    Science.gov (United States)

    Yazdi, Fatemeh-Maleknejad; Atai, Mohammad; Zeynali, Mahsa

    2015-01-01

    Background The aim of this study was to investigate the effect of different concentrations of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) monomer in one-step self-etch experimental adhesives on dentinal microshear bond strength (µSBS), their degree of conversion and bonded micro structure. Material and Methods Composite resin cylinders (Clearfil AP-X) were bonded on human sound molar dentinal surfaces by using five experimental one-step self-etching adhesives (1-SEAs) containing 0% (E0), 5% (E5), 10% (E10), 15% (E15), 20% (E20) (by weight) 10-MDP monomer and Clearfil S3 Bond (CS3) as a control. After 24 hours, microshear bond strength was tested. The degree of conversion was also measured using Fourier transform infrared spectroscopy. Interfacial ultrastructure was observed under a scanning electron microscope in all the groups. Results A higher microshear bond strength was observed with adhesives containing 10% and 15% 10-MDP in comparison to study groups (PSelf-etch adhesives, 10-MDP, bond strength, degree of conversion. PMID:26155340

  13. Development of optimal enzymatic and microbial conversion systems for biofuel production

    Science.gov (United States)

    Aramrueang, Natthiporn

    The increase in demand for fuels, along with the concerns over the depletion of fossil fuels and the environmental problems associated with the use of the petroleum-based fuels, has driven the exploitation of clean and renewable energy. Through a collaboration project with Mendota Bioenergy LLC to produce advanced biofuel from sugar beet and other locally grown crops in the Central Valley of California through demonstration and commercial-scale biorefineries, the present study focused on the investigation of selected potential biomass as biofuel feedstock and development of bioconversion systems for sustainable biofuel production. For an efficient biomass-to-biofuel conversion process, three important steps, which are central to this research, must be considered: feedstock characterization, enzymatic hydrolysis of the feedstock, and the bioconversion process. The first part of the research focused on the characterization of various lignocellulosic biomass as feedstocks and investigated their potential ethanol yields. Physical characteristics and chemical composition were analyzed for four sugar beet varieties, three melon varieties, tomato, Jose tall wheatgrass, wheat hay, and wheat straw. Melons and tomato are those products discarded by the growers or processors due to poor quality. The mass-based ethanol potential of each feedstock was determined based on the composition. The high sugar-containing feedstocks are sugar beet roots, melons, and tomato, containing 72%, 63%, and 42% average soluble sugars on a dry basis, respectively. Thus, for these crops, the soluble sugars are the main substrate for ethanol production. The potential ethanol yields, on average, for sugar beet roots, melons, and tomato are 591, 526, and 448 L ethanol/metric ton dry basis (d.b.), respectively. Lignocellulosic biomass, including Jose Tall wheatgrass and wheat straw, are composed primarily of cellulose (27-39% d.b.) and hemicellulose (26-30% d.b.). The ethanol yields from these

  14. Solar thermal conversion

    Science.gov (United States)

    Selcuk, M. K.

    1978-01-01

    A brief review of the fundamentals of the conversion of solar energy into mechanical work (or electricity via generators) is given. Both past and present work on several conversion concepts are discussed. Solar collectors, storage systems, energy transport, and various types of engines are examined. Ongoing work on novel concepts of collectors, energy storage and thermal energy conversion are outlined and projections for the future are described. Energy costs for various options are predicted and margins and limitations are discussed.

  15. Solar electric and thermal conversion system in close proximity to the consumer. [solar panels on house roofs

    Science.gov (United States)

    Boeer, K. W.

    1975-01-01

    Solar cells may be used to convert sunlight directly into electrical energy and into lowgrade heat to be used for large-scale terrestrial solar-energy conversion. Both forms of energy can be utilized if such cells are deployed in close proximity to the consumer (rooftop). Cadmium-sulfide/copper-sulfide (CdS/Cu2S) solar cells are an example of cells which may be produced inexpensively enough to become economically attractive. Cell parameters relevant for combined solar conversion are presented. Critical issues, such as production yield, life expectancy, and stability of performance, are discussed. Systems-design parameters related to operating temperatures are analyzed. First results obtained on Solar One, the experimental house of the University of Delaware, are given. Economic aspects are discussed. Different modes of operation are discussed in respect to the power utility and consumer incentives.

  16. Influence of the photoinitiator system and light photoactivation units on the degree of conversion of dental composites

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Celerino de Moraes Porto

    2010-12-01

    Full Text Available The aim of this study was to observe the influence of two light polymerization units (LED or halogen light on the degree of conversion (DC of three dental composites with lighter shades and a different photoinitiator system. The top (T and bottom (B surfaces of 60 discs of composite resin (Filtek™ Supreme, Filtek™ Z250, Tetric™ Ceram Bleach cured either by LED or by halogen lamp (HL were studied using an FT-Raman spectrometer. The degree of conversion (DC was evaluated by following the changes in the intensity of the methacrylate C=C stretching mode at 1640 cm-1. The calculated DC ranged from 54.2% (B to 73.4% (T and from 60.2% (B to 76.6% (T for the LED and HL, respectively. LED and halogen devices were able to produce an adequate DC for all the resins tested.

  17. Conversion of radioactive and hazardous chemical wastes into borosilicate glass using the glass material oxidation and dissolution system

    Energy Technology Data Exchange (ETDEWEB)

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.; Elam, K.R. [Oak Ridge National Lab., TN (United States)

    1996-12-31

    A new vitrification process has been invented. The Glass Material Oxidation and Dissolution System (GMODS) allows direct conversion of radioactive and hazardous chemical wastes to borosilicate glass. GMODS directly converts metals, ceramics and amorphous solids to glass, oxidizes organics with the residue converted to glass, and converts halides (such as chlorides) to borosilicate glass and a secondary sodium halide stream. The glass is designed to meet EPA criteria for chemically non-hazardous waste forms. Laboratory work has demonstrated the conversion of stainless steel, aluminum, cerium (a plutonium surrogate), uranium, Zircaloy, multiple oxides and other materials to glass. Equipment options have been identified for processing rates between 1 and 100,000 t/y. Significant work, including a pilot plant, is required to develop GMODS for applications at an industrial scale.

  18. Evaluating Monitoring Systems in the European Social Fund Context: A Sociotechnical Approach

    Science.gov (United States)

    Iannacci, Federico; Cornford, Tony; Cordella, Antonio; Grillo, Francesco

    2009-01-01

    In contrast to the prevailing image of monitoring systems as technical systems, it is proposed that they should rather be conceived of as social endeavors at exchanging information. Drawing on the monitoring and evaluation framework of Cornford, Doukidis, and Forster, the concept of information agreement is suggested as a way of assessing the…

  19. Conversion of Hanford site well locations to Washington coordinate system of 1983, South Zone 1991 (WCS83S)

    Energy Technology Data Exchange (ETDEWEB)

    Burnett, R.A.; Tzemos, S. [Pacific Northwest Lab., Richland, WA (United States); Dietz, L.A. [Westinghouse Hanford Co., Richland, WA (United States)

    1993-12-01

    Past construction and survey practices have resulted in the use of multiple local coordinate systems for measuring and reporting the horizontal position of wells and other facilities and locations on the Hanford Site. This report describes the development of a coordinate transformation process and algorithm and its application to the conversion of the horizontal coordinates of Hanford site wells from the various local coordinate systems and datums to a single standard coordinate system, the Washington Coordinate system of 1983, South Zone 1991 (WCS83S). The coordinate transformation algorithm, implemented as a computer program called CTRANS, uses standard two-dimensional translation, rotation, and scaling transformation equations and can be applied to any set of horizontal point locations. For each point to be transformed, the coefficients of the transformation equations are calculated locally, using the coordinates of the three nearest registration points (points with known locations in both coordinate systems). The report contains a discussion of efforts to verify and validate both the software and the well location data, a description of the methods used to estimate transformation and registration point accuracy, instructions for using the computer program, and a summary of the Hanford well conversion results for each local coordinate system and datum. Also included are the results of using recent U.S. Army Corps of Engineers survey data to obtain estimated measures of location errors in wells for which the local coordinate data source is undocumented, unverified, and therefore of unknown accuracy.

  20. Comparison of simulations and offshore measurement data of a prototype of a floating combined wind and wave energy conversion system

    DEFF Research Database (Denmark)

    Yde, Anders; Larsen, Torben J.; Hansen, Anders Melchior

    2015-01-01

    In this paper, results from comparisons of simulations and measured offshore data from a floating combined wind and wave energy conversion system are presented. The device is a downscaled prototype that consists of a floating platform equipped with ten wave energy absorbers and three wind turbines....... The numerical model of the platform is based on the aeroelastic code, HAWC2, developed by DTU Wind Energy, which is coupled with a special external system that reads the output generated directly by the wave analysis software, WAMIT. The model also includes models for the dynamic mooring lines as well...

  1. Digital computer study of nuclear reactor thermal transients during startup of 60-kWe Brayton power conversion system

    Science.gov (United States)

    Jefferies, K. S.; Tew, R. C.

    1974-01-01

    A digital computer study was made of reactor thermal transients during startup of the Brayton power conversion loop of a 60-kWe reactor Brayton power system. A startup procedure requiring the least Brayton system complication was tried first; this procedure caused violations of design limits on key reactor variables. Several modifications of this procedure were then found which caused no design limit violations. These modifications involved: (1) using a slower rate of increase in gas flow; (2) increasing the initial reactor power level to make the reactor respond faster; and (3) appropriate reactor control drum manipulation during the startup transient.

  2. Pension Fund

    CERN Multimedia

    2006-01-01

    Following the approval by the CERN Council, at its Session in March 2006, of the amendments to Administrative Circular No. 14 (Protection of the members of the personnel against the financial consequences of illness, accident and disability) and the resulting amendments to the Rules and Regulations of the Pension Fund, which entered into force on 1st July 2006, the Administration of the Fund has decided to publish a complete new edition of the Rules and Regulations incorporating all amendments up to 1st July 2006. Members of the Fund will be informed once the new edition of the Rules and Regulations is available from Departmental secretariats.In the meantime, the amendments to the text of the Pension Fund Rules and Regulations, which entered into force on 1st July 2006, are presented below (Previous text/Amended text): Chapter II - Section 1: Contributions and benefits Article II 1.04 - Reference Salary - Part-time Work OLD TEXT: The reference salary of a member with a contract for part-time work shall b...

  3. Pension Fund

    CERN Multimedia

    2006-01-01

    Following the approval by the CERN Council, at its Session in March 2006, of the amendments to Administrative Circular No. 14 (Protection of the members of the personnel against the financial consequences of illness, accident and disability) and the resulting amendments to the Rules and Regulations of the Pension Fund, which entered into force on 1st July 2006, the Administration of the Fund has decided to publish a complete new edition of the Rules and Regulations incorporating all amendments up to 1st July 2006. Members of the Fund will be informed once the new edition of the Rules and Regulations is available from Departmental secretariats. In the meantime, the amendments to the text of the Pension Fund Rules and Regulations, which entered into force on 1st July 2006, are presented below (Previous text/Amended text) : Chapter II - Section 1: Contributions and benefits Article II 1.04 - Reference Salary - Part-time Work OLD TEXT: the reference salary of a member with a contract for part-time work shall be e...

  4. PENSION FUND

    CERN Multimedia

    2002-01-01

    The Governing Board of the Pension Fund held its 104th and 105th meetings on 8th November and 4th December 2001, respectively. The agenda of the 8th November meeting was devoted to a single item, namely the outcome of the Finance Committee's meeting the previous day. The Governing Board noted with satisfaction that both its proposed amendments to the Rules and Regulations of the Fund - allowing, in particular, the award of a deferred retirement pension after five years of service - and its proposal for the adjustment of pensions on 1.1.2002 had been approved for recommendation to the Council in December. At its meeting on 4th December, the Governing Board dealt mainly with the items examined at the latest meeting of the Investment Committee. The Committee's chairman, G. Maurin, stated that the 2001 return on the Fund's overall investments was likely to be between -2% and -3%. He also noted that a new study of the Fund's cash flows (incomings and outgoings) had been performed. He underlined that, while the flo...

  5. Half-time Tc-99m sestamibi imaging with a direct conversion molecular breast imaging system.

    Science.gov (United States)

    Hruska, Carrie B; Conners, Amy Lynn; Jones, Katie N; Weinmann, Amanda L; Lingineni, Ravi K; Carter, Rickey E; Rhodes, Deborah J; O'Connor, Michael K

    2014-01-15

    In an effort to reduce necessary acquisition time to perform molecular breast imaging (MBI), we compared diagnostic performance of MBI performed with standard 10-min-per-view acquisitions and half-time 5-min-per-view acquisitions, with and without wide beam reconstruction (WBR) processing. Eighty-two bilateral, two-view MBI studies were reviewed. Studies were performed with 300 MBq Tc-99 m sestamibi and a direct conversion molecular breast imaging (DC-MBI) system. Acquisitions were 10 min-per-view; the first half of each was extracted to create 5-min-per-view datasets, and WBR processing was applied.The 10-min-, 5-min-, and 5-min-per-view WBR studies were independently interpreted in a randomized, blinded fashion by two radiologists. Assessments of 1 to 5 were assigned; 4 and 5 were considered test positive. Background parenchymal uptake, lesion type, distribution of non-mass lesions, lesion intensity, and image quality were described. Considering detection of all malignant and benign lesions, 5 min-per-view MBI had lower sensitivity (mean of 70% vs. 85% (p ≤ 0.04) for two readers) and lower area under curve (AUC) (mean of 92.7 vs. 99.6, p ≤ 0.01) but had similar specificity (p = 1.0). WBR processing did not alter sensitivity, specificity, or AUC obtained at 5 min-per-view.Overall agreement in final assessment between 5-min-per-view and 10-min-per-view acquisition types was near perfect (κ = 0.82 to 0.89); however, fair to moderate agreement was observed for assessment category 3 (probably benign) (κ = 0.24 to 0.48). Of 33 malignant lesions, 6 (18%) were changed from assessment of 4 or 5 with 10-min-per-view MBI to assessment of 3 with 5-min-per-view MBI. Image quality of 5-min-per-view studies was reduced compared to 10-min-per-view studies for both readers (3.24 vs. 3.98, p < 0.0001 and 3.60 vs. 3.91, p < 0.0001). WBR processing improved image quality for one reader (3.85 vs. 3.24, p < 0.0001). Although similar

  6. Motor starting a Brayton cycle power conversion system using a static inverter

    Science.gov (United States)

    Curreri, J. S.; Edkin, R. A.; Kruchowy, R.

    1973-01-01

    The power conversion module of a 2- to 15-kWe Brayton engine was motor started using a three-phase, 400-hertz static inverter as the power source. Motor-static tests were conducted for initial gas loop pressures of 10, 14, and 17 N/sq cm (15, 20, and 25 psia) over a range of initial turbine inlet temperatures from 366 to 550 K (200 to 530 F). The data are presented to show the effects of temperature and pressure on the motor-start characteristics of the rotating unit. Electrical characteristics during motoring are also discussed.

  7. Hydrogen Production from Water by Photosynthesis System I for Use as Fuel in Energy Conversion Devices (a.k.a. Understanding Photosystem I as a Biomolecular Reactor for Energy Conversion)

    Science.gov (United States)

    2014-04-01

    Hydrogen Production from Water by Photosynthesis System I for Use as Fuel in Energy Conversion Devices (a.k.a. Understanding Photosystem I as...Laboratory Adelphi, MD 20783-1197 ARL-TR-6904 April 2014 Hydrogen Production from Water by Photosynthesis System I for Use as Fuel in Energy...Final 3. DATES COVERED (From - To) 10/1/2010–10/1/2013 4. TITLE AND SUBTITLE Hydrogen Production from Water by Photosynthesis System I for Use as Fuel

  8. Energy systems programs funded by the Assistant Secretary for Environment, Safety and Health: FY 1993--FY 1994

    Energy Technology Data Exchange (ETDEWEB)

    Buttram, A.W. [ed.

    1994-12-31

    This document presents an overview of work at Martin Marietta Energy Systems, Inc., (Energy Systems) during FY 1993--FY 1994 that was funded by the Department of Energy`s (DOE`s) Assistant Secretary for Environment, Safety and Health (ASEH). To illustrate the programmatic breadth of Energy Systems and to establish the context within which this work was accomplished, this document also includes representative descriptions of ASEH-related work at Energy Systems done for other sponsors. Activities for ASEH cover a wide variety of subjects that are geared towards the environmental, safety, and health aspects of DOE operations. Subjects include the following: environmental compliance, environmental guidance, environmental audits, NEPA oversight, epidemiology and health surveillance, transportation and packaging safety, safety and quality assurance; technical standards, performance indicators, occurrence reporting, health physics instrumentation, risk management, security evaluations, and medical programs. The technical support section describes work in progress for ASEH, including specific program accomplishments. The work for others section describes work for non-ASEH sponsors that reinforces and supplements the ASEH work. Appendix A includes a list of FY 1993--FY 1994 publications related to the ASEH work.

  9. Analysis of Central Design Agency Alternatives for Navy Industrial Fund Accounting Systems: A Proposed Methodology.

    Science.gov (United States)

    1980-03-01

    advances in computer software and hardware tecnology , has rendered the systems development efforts for individual ADP applications by similiar functional...Resource Management Education Center Naval Postgraduate School Monterey, California 93940 5. CDR E. A. Fincke, SC, USN Code 54FI Department of

  10. EPA Funds Coastal Observation System for Indicators of Ocean Acidification in Casco Bay

    Science.gov (United States)

    The U.S. Environmental Protection Agency provided a total of $85 thousand toward establishing a state-of-the-art coastal observing system in Casco Bay Maine to help coastal managers evaluate the threat of coastal acidification from excess CO 2.

  11. Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion

    Directory of Open Access Journals (Sweden)

    Narang Prineha

    2016-06-01

    Full Text Available Surface plasmons provide a pathway to efficiently absorb and confine light in metallic nanostructures, thereby bridging photonics to the nano scale. The decay of surface plasmons generates energetic ‘hot’ carriers, which can drive chemical reactions or be injected into semiconductors for nano-scale photochemical or photovoltaic energy conversion. Novel plasmonic hot carrier devices and architectures continue to be demonstrated, but the complexity of the underlying processes make a complete microscopic understanding of all the mechanisms and design considerations for such devices extremely challenging.Here,we review the theoretical and computational efforts to understand and model plasmonic hot carrier devices.We split the problem into three steps: hot carrier generation, transport and collection, and review theoretical approaches with the appropriate level of detail for each step along with their predictions.We identify the key advances necessary to complete the microscopic mechanistic picture and facilitate the design of the next generation of devices and materials for plasmonic energy conversion.

  12. Pension Fund

    CERN Multimedia

    Pension Fund

    2006-01-01

    Amendment No. 22 to the Rules and Regulations of the Pension Fund has just been published and can be obtained from Department/Unit secretariats or, in the case of pensioners, directly from the Administration of the Fund (tel. 767-91 94/27 38), bldg 5, 1-030. This Amendment, which entered into force following the CERN Council's decisions of 16 December 2005, includes the following new articles: Art. II 5.08 : Non-entitlement to Pension for Surviving Spouse Art. II 5.09 : Procurement of an entitlement to Pension for Surviving Spouse Art. II 6.09 : Non-entitlement to Pension for Orphans Art. II 7.01 c) : Entitlement to Allowances Art. III 1.07 : Extension of the contract beyond the age limit of 65 as well as the following amended articles : Article II 1.07 - Contributions Annex B - Fixed sums and allowances

  13. Using Federally Funded Curricular Materials to meet Next Geneartion Science Standards in Earth System Science

    Science.gov (United States)

    McAuliffe, C.

    2015-12-01

    The Next Generation Science Standards (NGSS) describe teaching and learning goals for Earth system science at all levels of K-12, including elementary, middle school, and high school. Teachers must consider science and engineering practices, cross-cutting concepts, and disciplinary core ideas. The National Science Foundation and other federal organizations have supported the development of reformed curricular materials at the K-12 level for many years. Although developed before the adoption of NGSS, many of these Earth system science resources are, in fact, NGSS congruent. Such resources include those developed by TERC, SERC, EDC, NASA, NOAA, USGS, and others. This session features NGSS congruent materials, carefully examining and dissecting the performance expectations that embody these materials. It also shares a process of tagging these materials via NSTA's, NGSS portal guidelines.

  14. Pension Fund

    CERN Multimedia

    2003-01-01

    The Governing Board of the Pension Fund held its hundred and seventeenth meeting on 3 June 2003. On that occasion, it examined the recommendations made by the External Auditors in their report on their audit of the 2002 annual accounts and the replies by the Pension Fund's Administration. The Governing Board was gratified by the small number of remarks by the External Auditors. It also confirmed its agreement to the procedure followed by the Administration of the Pension Fund in the handling of transfer values. Under other items on the agenda, the Board once again examined ESO's request relating to the terms and conditions of membership by its staff members. In this regard, the Board wishes to receive from ESO a definitive request (following the necessary consultation procedures with the representatives of the personnel and discussions within ESO's governing bodies) so that the working group can continue its work on a clear basis and so that the Governing Board is in a position to take up a position in the m...

  15. PENSION FUND

    CERN Document Server

    Administration of the Fund

    2001-01-01

    The Administration of the Fund has just signed a contract with the 'La Suisse' insurance company, making life insurance available to persons leaving CERN under very similar conditions to those offered to the members of the CERN personnel. From now on, persons retiring from the Organization will be able to take out this new insurance at the moment of retirement, provided that they have been members of CERN's collective life insurance scheme for the last five years of service. Exceptionally, until the end of 2001, 'La Suisse' has agreed to allow persons who are already retired to take out this insurance, subject to their state of health (health questionnaire to be completed) and with a maximum insured amount set at 150,000 CHF. We therefore invite any retired persons interested in this insurance to consult the detailed terms and conditions, either on the Pension Fund's Web site (http://pensions.web.cern.ch/pensions) or by writing to the Administration of the Fund. For those wishing to apply, the documents to be...

  16. Applied research on energy storage and conversion for photovoltaic and wind energy systems. Volume II. Photovoltaic systems with energy storage. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    This volume of the General Electric study was directed at an evaluation of those energy storage technologies deemed best suited for use in conjunction with a photovoltaic energy conversion system in utility, residential and intermediate applications. Break-even cost goals are developed for several storage technologies in each application. These break-even costs are then compared with cost projections presented in Volume I of this report to show technologies and time frames of potential economic viability. The form of the presentation allows the reader to use more accurate storage system cost data as they become available. The report summarizes the investigations performed and presents the results, conclusions and recommendations pertaining to use of energy storage with photovoltaic energy conversion systems. Candidate storage concepts studied include (1) above ground and underground pumped hydro, (2) underground compressed air, (3) electric batteries, (4) flywheels, and (5) hydrogen production and storage. (WHK)

  17. Ocean Thermal Energy Conversion: An overview

    Energy Technology Data Exchange (ETDEWEB)

    1989-11-01

    Ocean thermal energy conversion, or OTEC is a technology that extracts power from the ocean's natural thermal gradient. This technology is being pursued by researchers from many nations; in the United States, OTEC research is funded by the US Department of Energy's Ocean Energy Technology program. The program's goal is to develop the technology so that industry can make a competent assessment of its potential -- either as an alternative or as a supplement to conventional energy sources. Federally funded research in components and systems will help OTEC to the threshold of commercialization. This publication provides an overview of the OTEC technology. 47 refs., 25 figs.

  18. Design Concepts for RF-DC Conversion in Particle Accelerator Systems

    CERN Document Server

    Caspers, F; Grudiev, A; Sapotta, H

    2010-01-01

    In many particle accelerators considerable amounts of RF power reaching the megawatt level are converted into heat in dummy loads. After an overview of RF power in the range 200 MHz to 1 GHz dissipated at CERN we discuss several developments that have come up in the past using vacuum tube technology for RF-DC conversion. Amongst those the developments of the cyclotron wave converter CWC appears most suitable. With the availability of powerful Schottky diodes the solid state converter aspect has to be addressed as well. One of the biggest problems of Schottky diode based structures is the junction capacity. GaAs and GaN Schottky diodes show a significant reduction of this junction capacity as compared to silicon. Small rectenna type converter units which have been already developed for microwave powered helicopters can be used in waveguides or with coaxial power dividers.

  19. A comparison of Stirling engines for use with a 25 kW dish-electric conversion system

    Science.gov (United States)

    Shaltens, Richard K.

    1987-01-01

    Two designs for an advanced Stirling conversion system (ASCS) are described. The objective of the ASCS is to generate about 25 kW of electric power to an electric utility grid at an engine/alternator target cost of $300.00/kW at the manufacturing rate of 10,000 unit/yr. Both designs contain a free-piston Stirling engine (FPSE), a heat transport system, solar receiver, a means to generate electric power, the necessary auxiliaries, and a control system. The major differences between the two concepts are: one uses a 25 kWe single-piston FPSE which incorporates a linear alternator to directly convert the energy to electricity on the utility grid; and in the second design, electrical power is generated indirectly using a hydraulic output to a ground based hydraulic motor coupled to a rotating alternator. Diagrams of the two designs are presented.

  20. Demonstration of simultaneous mode conversion and demultiplexing for mode and wavelength division multiplexing systems based on tilted few-mode fiber Bragg gratings.

    Science.gov (United States)

    Gao, Ya; Sun, Junqiang; Chen, Guodong; Sima, Chaotan

    2015-04-20

    We experimentally demonstrate mode conversion by exploiting optical reflection of tilted few-mode fiber Bragg grating (FM-FBG). Mode conversions from LP(01) mode to higher symmetric and asymmetric modes are achieved, and more than 99.5% conversion efficiency from LP(01) to LP(11) mode is obtained using a 1.6°-tilted FM-FBG. Influences of the weakly tilted FM-FBG parameters on the property of mode conversion is analyzed and discussed. A simultaneous mode conversion and demultiplexing scheme for 4-mode × 3-wavelength multiplexing transmission is proposed and the modal crosstalk is analyzed based on the transmission spectra of the tilted FM-FBGs. The proposed approach shows potential applications in mode and wavelength division multiplexing communication systems.

  1. How do hospital administrators perceive cardiac rehabilitation in a publicly-funded health care system?

    Science.gov (United States)

    Grace, Sherry L; Scarcello, Sabrina; Newton, Janet; O'Neill, Blair; Kingsbury, Kori; Rivera, Tiziana; Chessex, Caroline

    2013-03-28

    Patient and provider-related factors affecting access to cardiac rehabilitation (CR) have been extensively studied, but health-system administration factors have not. The objectives of this study were to investigate hospital administrators' (HA) awareness and knowledge of cardiac rehabilitation (CR), perceptions regarding resources for and benefit of CR, and attitudes toward and implementation of inpatient transition planning for outpatient CR. A cross-sectional and observational design was used. A survey was administered to 679 HAs through Canadian and Ontario databases. A descriptive examination was performed, and differences in HAs' perceptions by role, institution type and presence of within-institution CR were compared using t-tests. 195 (28.7%) Canadian HAs completed the survey. Respondents reported good knowledge of what CR entails (mean=3.42±1.15/5). Awareness of the closest site was lower among HAs working in community versus academic institutions (3.88±1.24 vs. 4.34±0.90/5 respectively; p=.01). HAs in non-executive roles (4.77±0.46/5) perceived greater CR importance for patients' care than executives (4.52±0.57; p=.001). HAs perceived CR programs should be situated in both hospitals and community settings (n=134, 71.7%). HAs value CR as part of patients' care, and are supportive of greater CR provision. Those working in community settings and executives may not be as aware of, or less-likely to value, CR services. CR leaders from academic institutions might consider liaising with community hospitals to raise awareness of CR benefits, and advocate for it with the executives in their home institutions.

  2. Resolving the International Monetary Fund's Legitimacy Crisis

    DEFF Research Database (Denmark)

    Seabrooke, Leonard

    2006-01-01

    Since the Asian financial crisis of 1997-1998 the International Monetary Fund (the Fund) has been embroiled in an international crisis of legitimacy. Assertions of a crisis are premised on the notions that the Fund's voting system is unfair, and that the Fund enforces homogenous policies onto...

  3. 12 CFR 619.9185 - Funding Corporation.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Funding Corporation. 619.9185 Section 619.9185 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM DEFINITIONS § 619.9185 Funding Corporation. The term Funding Corporation refers to the Federal Farm Credit Banks Funding Corporation...

  4. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Credit conversion factors-off-balance sheet items. 615.5212 Section 615.5212 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM FUNDING...-market value, if positive) to the potential future credit exposure, determined by multiplying the...

  5. Mutual Fund Exit and Mutual Fund Fees

    OpenAIRE

    Philip C. English II; Ilhan Demiralp; William P. Dukes

    2011-01-01

    We examine the effect of mutual fund fee structure on mutual fund exit mode and timing. The evidence presented herein is consistent with fee maximization by mutual fund sponsors or managers, increased conflicts of interest for funds charging 12b-1 fees and higher management fees, and a pecking order for mutual fund exit method. Specifically, mutual fund exits that result in decreased fee income are delayed relative to exits that do not and exit strategies that retain fee income are more likel...

  6. PENSION FUND

    CERN Multimedia

    Administration of the Fund

    2001-01-01

    The Administration of the Fund has just signed a contract with the 'La Suisse' insurance company, making life insurance available to persons leaving CERN under very similar conditions to those offered to the members of the CERN personnel. From now on, persons retiring from the Organization will be able to take out this new insurance at the moment of retirement, provided that they have been members of CERN's collective life insurance scheme for the last five years of service. Exceptionally, until the end of 2001, 'La Suisse' has agreed to allow persons who are already retired to take out this insurance, provided that they are less than 70 years old and subject to their state of health (health questionnaire to be completed) and with a maximum insured amount set at 150,000 CHF. We therefore invite any retired persons interested in this insurance to consult the detailed terms and conditions, either on the Pension Fund's Web site (http://pensions.web.cern.ch/pensions) or contacting to the Administration of the Fun...

  7. High Efficiency Three Phase Resonant Conversion for Standardized Architecture Power System Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A low-cost, standardized-architecture power system is proposed for NASA electric propulsion (EP) applications. Three approaches are combined to develop a system that...

  8. GEO-TEP. Development of thermoelectric materials for geothermal energy conversion systems. Final report 2008

    Energy Technology Data Exchange (ETDEWEB)

    Bocher, L.; Weidenkaff, A.

    2008-07-01

    Geothermal heat can be directly converted into electricity by using thermoelectric converters. Thermoelectric conversion relies on intrinsic materials properties which have to be optimised. In this work novel environmentally friendly and stable oxide ceramics were developed to fulfil this task. Thus, manganate phases were studied regarding their potential thermoelectric properties for converting geothermal heat into electricity. Perovskite-type phases were synthesized by applying different methods: the ceramic route, and innovative synthesis routes such as the 'chimie douce' method by bulk thermal decomposition of the citrate precursor or using an USC process, and also the polyol-mediated synthesis route. The crystal structures of the manganate phases are evaluated by XRPD, NPD, and ED techniques while specific microstructures such as twinned domains are highlighted by HRTEM imaging. Besides, the thermal stability of the Mn-oxide phases in air atmosphere are controlled over a wide temperature range (T < 1300 K). The thermoelectric figure of merit ZT was enhanced from 0.021 to 0.3 in a broad temperature range for the studied phases which makes these phases the best perovskitic candidates as n-type polycrystalline thermoelectric materials operating in air at high temperatures. (author)

  9. Spin-symmetry conversion and internal rotation in high J molecular systems

    Science.gov (United States)

    Mitchell, Justin; Harter, William

    2006-05-01

    Dynamics and spectra of molecules with internal rotation or rovibrational coupling is approximately modeled by rigid or semi-rigid rotors with attached gyroscopes. Using Rotational Energy (RE)^1 surfaces, high resolution molecular spectra for high angular momentum show two distinct but related phenomena; spin-symmetry conversion and internal rotation. For both cases the high total angular momentum allows for transitions that would otherwise be forbidden. Molecular body-frame J-localization effects associated with tight energy level-clusters dominate the rovibronic spectra of high symmetry molecules, particularly spherical tops at J>10. ^2 The effects include large and widespread spin-symmetry mixing contrary to conventional wisdom^3 about weak nuclear moments. Such effects are discussed showing how RE surface plots may predict them even at low J. Classical dynamics of axially constrained rotors are approximated by intersecting rotational-energy-surfaces (RES) that have (J-S).B.(J-S) forms in the limit of constraints that do no work. Semi-classical eigensolutions are compared to those found by direct diagonalization. ^1 W.G Hater, in Handbook of Atomic, Molecular and Optical Physics, edited by G.W.F Drake (Springer, Germany 2006) ^2 W. G. Harter, Phys. Rev. A24,192-262(1981). ^3 G. Herzberg, Infrared and Raman Spectra (VanNostrand 1945) pp. 458,463.

  10. Design and Properties of an Immobilization Enzyme System for Inulin Conversion.

    Science.gov (United States)

    Hang, Hua; Wang, Changbao; Cheng, Yiqun; Li, Ning; Song, Liuli

    2018-02-01

    A commercial inulinase could convert inulin into fructose, which was optimized to be entrapped in the calcium alginate-gelatin beads with the immobilization yield of 86% for free inulinase activities. The optimum pH values and temperatures were 4.5 and 40 °C for the free enzyme and 5.0-5.5 and 45-50 °C for the immobilized enzyme. The kinetic parameters of V max and K m were 5.24 μmol/min and 57.6 mg/mL for the free inulinase and 4.32 μmol/min and 65.8 mg/mL for the immobilized inulinase, respectively. The immobilized enzyme retained 80% of its initial activities at 45 °C for 4 days, which could exhibit better thermal stability. The reuse of immobilized inulinase throughout the continuous batch operations was explored, which had better reusability of the immobilized biocatalyst. At the same time, the stability of immobilized enzyme in the continuous packed-bed bioreactor was estimated, which showed the better results and had its potential scale-up fructose production for inulin conversion.

  11. Environmental studies related to the operation of wind energy conversion systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, S.E.; Cornaby, B.W.; Rodman, C.W.; Sticksel, P.R.; Tolle, D.A.

    1977-12-01

    This biophysical impact assessment explores the environmental consequences of the emerging wind energy conversion technology through field studies done at the DOE/NASA 100-kW Experimental Wind Turbine located at NASA Lewis Research Center's Plum Brook Station near Sandusky, Ohio. A micrometeorological field program monitored changes in the downwind wake of the wind turbine. Horizontal and/or vertical measurements of wind speed, temperature, carbon dioxide concentration, precipitation, and incident solar radiation showed measurable variation within the wake only for precipitation and wind speed. The changes were minor and not likely to result in any secondary effects to vegetation, including crops, because they are within the natural range of variability in the site environment. Effects are negligible beyond the physically altered area of the tower pad, access, and control structures. The wind turbine has not proved to be a high risk to airborne fauna, including the most vulnerable night-migrating songbirds. Behavioral studies indicate the birds will avoid the turbine if they can see it.

  12. Modelling Of Converter Characteristics of Wind Energy Conversion System during Voltage Sags

    OpenAIRE

    Pratyusha Dikkala,; B. Srinivasa Rao

    2014-01-01

    The proposed system presents power-control strategies of a grid-connected hybrid generation system with versatile power transfer. This hybrid system allows maximum utilization of freely available renewable energy sources like wind and photovoltaic energies. For this, an adaptive maximum power point tracking (MPPT) algorithm along with standard perturbs and observe method will be used for the system. The turbine rotor speed is the main determinant of mechanical output from wind energy and Sola...

  13. Proceedings of the fourth biennial conference and workshop on wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Kottler, Jr., R. J. [ed.

    1980-06-01

    Separate abstracts are included for papers presented concerning research and development requirements and utility interface and institutional issues for small-scale systems; design requirements and research and development requirements for large-scale systems; economic and operational requirements of large-scale wind systems; wind characteristics and wind energy siting; international activities; wind energy applications in agriculture; federal commercialization and decentralization plans; and wind energy innovative systems.

  14. An integrated, semi-automated approach to thermochemical conversion research for sustainable farming systems

    Science.gov (United States)

    An integrated, semi-automated system is presented for the rapid and efficient testing and production of research-scale quantities of biochar. This biochar, produced from agricultural waste materials, can easily be incorporated in future sustainable livestock farming systems. These farming systems wi...

  15. High conversion self-curing sealer based on a novel injectable polyurethane system for root canal filling

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Bin [Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu 610064 (China); Zuo, Yi, E-mail: zoae@scu.edu.cn [Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu 610064 (China); Li, Jidong; Wang, Li [Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu 610064 (China); Tang, Kuangyun [The State Key Laboratory of Oral Diseases and Orthognathic Surgery, Sichuan University West China College of Stomatology, Chengdu 610064 (China); Huang, Di; Du, Jingjing; Luo, Peipei; Li, Yubao [Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu 610064 (China)

    2013-08-01

    Low monomer–polymer conversion is the key factor leading to cytotoxicity for resin-containing restorative materials. This paper provides a new root canal filling system based on self-curing injectable polyurethane which can achieve high conversion in a short time. Traced FTIR spectra show more than 90% NCO group participated in the curing reaction after 4 h, and only about 5% remained after 24 h. The calculated data also testified the curing process supports a third-order reaction, and this efficient and sufficient reaction is postulated to weaken the toxic stimulation. By culturing with L929 murine fibroblasts, the PU sealer is shown to be favorable for cell attachment and proliferation. Then physicochemical properties of the injectable PU-based sealer were evaluated according to the Standard [ISO 6876:2001 (E)] for clinical application. A series of physicochemical properties of PU sealer have been tested comparing with AH Plus and Apexit Plus. And the results present that the self-curing PU sealer could not only match the clinic requirements, but even has better properties than the other two commercial sealers. We expect the high conversion PU sealer has a tremendous potential in the field of root canal filling after further biological evaluation. - Highlights: • A new root canal sealer based on self-curing injectable polyurethane was provided. • More than 90% NCO group reacted after 4h, and only about 5% remained after 24 h. • By culturing with L929 murine fibroblasts, the PU sealer showed perfect cytocompatibility. • Volumetric dilatancy after curing will make the sealer achieve a tight seal.

  16. Computational modelling of Yorùbá numerals in a number-to-text conversion system

    Directory of Open Access Journals (Sweden)

    Olúgbénga O. Akinadé

    2014-08-01

    Full Text Available In this paper, we examine the processes underlying the Yorùbá numeral system and describe a computational system that is capable of converting cardinal numbers to their equivalent Standard Yorùbá number names. First, we studied the  mathematical and linguistic basis of the Yorùbá numeral system so as to formalise its arithmetic and syntactic procedures. Next, the process involved in formulating a Context-Free Grammar (CFG to capture the structure of the Yorùbá numeral system was highlighted.  Thereafter, the model was reduced into a set of computer programs to implement the numerical to lexical conversion process. System evaluation was done by ranking the output from the software and comparing the output with the representations given by a group of Yorùbá native speakers. The result showed that the system gave correct representation for numbers and produced a recall of 100% with respect to the collected corpus. Our future study is focused on developing a text normalisation system that will produce number names for other numerical expressions such as ordinal numbers, date, time, money, ratio, etc. in Yorùbá text.

  17. Advanced energy conversion and application - Decentralized energy systems. Papers; Fortschrittliche Energiewandlung und -anwendung - Schwerpunkt: Dezentrale Energiesysteme. Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Decentralized energy systems is the major topic of this VDI report which contains the proceedings of the VDI conference on advanced energy conversion and application. The decentralized energy systems are in the focus because it is expected that they will gain in significance in the course of restructuring and liberalisation of the energy markets and growing commitment to greenhouse gas mitigation. The subjects of the papers are the cogeneration technology in general, and specific systems for combined generation of heat, power and cold,(CHPC systems), systems for renewable energy generation, industrial energy technology, and analysis and optimization of energy systems. The report is intended to serve as a source of guidance and reference for manufacturers and operators of decentralized energy systems, for decision-making on energy policy, and for the energy industry, counselling firms and regulatory/surveillance bodies, and members of universities involved in relevant research and development work. (orig./CB) [German] Themenschwerpunkt des VDI-Berichts sind die dezentralen Energiesysteme, die im Spannungsfeld von fortschreitender Liberalisierung der Energiemaerkte und der Bemuehungen um die Reduzierung von Emissionen an Bedeutung gewinnen. Dabei widmen sich die Beitraege den Systemen zur Kraft-Waerme-Kaelte-Kopplung und zur Nutzung erneuerbarer Energie sowie der industriellen Energietechnik und der Analyse und Optimierung von Energiesystemen. Der Bericht wendet sich an Hersteller und Betreiber dezentraler Energieanlagen, an Entscheidungstraeger aus Politik und Wirtschaft, an Berater und Ueberwachungsinstitutionen sowie an auf diesem Gebiet taetige Hochschullehrer und -mitarbeiter. (orig.)

  18. Mass-energy balance analysis for estimation of light energy conversion in an integrated system of biological H2 production

    Directory of Open Access Journals (Sweden)

    A.I. Gavrisheva

    2015-12-01

    Full Text Available The present study investigated an integrated system of biological H2 production, which includes the accumulation of biomass of autotrophic microalgae, dark fermentation of biomass, and photofermentation of the dark fermentation effluent. Particular emphasis was placed on the estimation of the conversion efficiency of light into hydrogen energy at each stage of this system. For this purpose, the mass and energy balance regularities were applied. The efficiency of the energy transformation from light into the microalgal biomass did not exceed 5%. The efficiency of the energy transformation from biomass to biological H2 during the dark fermentation stage stood at about 0.3%. The photofermentation stage using the model fermentation effluent could improve this estimation to 11%, resulting in an overall efficiency 0.55%. Evidently, this scheme is counterproductive for light energy bioconversion due to numerous intermediate steps even if the best published data would be taken into account.

  19. Multivariable H{sub 2} and H{infinity} control for a wind energy conversion system - a comparison

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Ronilson; Coutinho, Gilmar Alves; Ferreira, Alexandre Jose; Torga, Flavio Allison [Universidade Federal de Ouro Preto (EM/DECAT/UFOP), MG (Brazil). Escola de Minas. Dept. de Engenharia de Controle e Automacao e de Tecnicas Fundamentais], Emails: rocha@em.ufop.br, gacoutinho@gmail.com, aleengaut@yahoo.com.br, torgautomacao@yahoo.com.br

    2010-10-15

    The Wind Energy Conversion System (WECS) is a nonlinear system, highly dependent on a stochastic variable characterized by sudden variations, and subjected to cyclical disturbances caused by operational phenomena. Thus, the quality of a WECS controller is measured by its capacity to deal with unmodeled dynamics, stochastic signals, and periodic, as well as non-periodic disturbances. Since the WECS' objectives can be easily specified in terms of maximum allowable gain in the disturbance-to-output transfer functions, H2 and H{infinity} methodologies can be good options for designing a WECS stabilizing controller, combining specifications such as: disturbance attenuation, asymptotic tracking, bandwidth limitation, robust stability, and trade-off between performance and control effort. Designs for WECS multivariable feedback controllers based on H2 and H{infinity} methodologies are presented in this paper. The performances of both controllers are computationally simulated, analyzed and compared in order to identify the advantages and drawbacks of each controller design. (author)

  20. Conversation Analysis.

    Science.gov (United States)

    Schiffrin, Deborah

    1990-01-01

    Summarizes the current state of research in conversation analysis, referring primarily to six different perspectives that have developed from the philosophy, sociology, anthropology, and linguistics disciplines. These include pragmatics; speech act theory; interactional sociolinguistics; ethnomethodology; ethnography of communication; and…

  1. Design techniques for modular integrated utility systems. [energy production and conversion efficiency

    Science.gov (United States)

    Wolfer, B. M.

    1977-01-01

    Features basic to the integrated utility system, such as solid waste incineration, heat recovery and usage, and water recycling/treatment, are compared in terms of cost, fuel conservation, and efficiency to conventional utility systems in the same mean-climatic area of Washington, D. C. The larger of the two apartment complexes selected for the test showed the more favorable results in the three areas of comparison. Restrictions concerning the sole use of currently available technology are hypothetically removed to consider the introduction and possible advantages of certain advanced techniques in an integrated utility system; recommendations are made and costs are estimated for each type of system.

  2. Prospects for the development of independent power supply systems on the basis of solid fuel thermal conversion technology

    Science.gov (United States)

    Sultanguzin, I. A.; Fedyukhin, A. V.; Kurzanov, S. Yu.; Gyulmaliev, A. M.; Stepanova, T. A.; Tumanovsky, V. A.; Titov, D. P.

    2015-05-01

    Theoretical principles of using solid fuel for organizing independent power supply to small settlements and industrial consumers are considered. Thermogravimetric experiments have been carried out for a few types of wood with determining the universal kinetic parameters characterizing the pyrolysis process. A procedure for describing the solid fuel thermal decomposition process has been proposed that is based on writing the equations of four independent parallel thermal decomposition reactions for each component of the initial raw material. A software package has been developed using which the calorific value, composition, and volume of the gas produced in the thermal conversion of solid fuels can be estimated. The impact of operating parameters on the synthesis gas composition has been evaluated. It has been found that increasing the thermal conversion temperature results in a higher calorific value of the obtained gas per unit weight of the feedstock. A qualitative and quantitative comparison of the computational model and the results obtained during experimental studies on the existing gasifier has been carried out. It is shown that the parameters of gas obtained on the test bench are consistent with the calculated ones in both the amount of gas and its chemical energy. The combined-cycle power plant flow chart involving the biomass gasification process has been numerically simulated in the Aspen Plus computer program, and calculations aimed at determining the optimal operating parameters of different thermal process circuit components and of the entire CCP system were performed.

  3. Conversion therapy of gastric cancer with massive malignant ascites and ovarian metastases by systemic and intraperitoneal chemotherapy.

    Science.gov (United States)

    Kondo, Tomohiro; Kitayama, Hiromitsu; Sugiyama, Junko; Hirayama, Michiaki; Suzuki, Yoshinori; Oyamada, Yumiko; Tsuji, Yasushi

    2016-12-01

    Intravenous and intraperitoneal paclitaxel with S-1 is showing promising results in gastric cancer with peritoneal metastases. We herein report a successful conversion of unresectable to resectable disease using combination chemotherapy with trastuzumab. The patient was a 39-year-old woman with human epidermal growth factor receptor 2-positive gastric cancer with peritoneal, pulmonary and bilateral ovarian metastases. After 6 cycles of S-1 plus cisplatin with trastuzumab, followed by 15 cycles of intravenous and intraperitoneal paclitaxel with S-1 and trastuzumab, the pulmonary and peritoneal metastases exhibited complete response and no evidence of malignancy was found on diagnostic laparoscopy. We performed metastasectomy of the bilateral sizeable ovaries, followed by total gastrectomy. The patient had no recurrence for 16 months after the gastrectomy. Therefore, satisfactory response to systemic and intraperitoneal chemotherapy may convert unresectable to resectable disease, and primary tumor resection with ovarian metastasectomy may prolong survival. This combination chemotherapy has the potential of becoming a conversion therapy for gastric cancer with peritoneal metastases, even if ascites and ovarian metastases are extensive.

  4. Proceedings of the third biennial conference and workshop on wind energy conversion systems. Volume I

    Energy Technology Data Exchange (ETDEWEB)

    Kornreich, T R [ed.

    1978-05-01

    Separate abstracts are included for 38 papers presented concerning large scale wind systems, small scale wind systems, regional and economic analysis, wind characteristics research, environmental and institutional considerations, and international activities. Four papers were previously input into the energy data base.

  5. Stability Constrained Efficiency Optimization for Droop Controlled DC-DC Conversion System

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2013-01-01

    implementing tertiary regulation. Moreover, system dynamic is affected when shifting VRs. Therefore, the stability is considered in optimization by constraining the eigenvalues arising from dynamic state space model of the system. Genetic algorithm is used in searching for global efficiency optimum while...

  6. Pension Fund governing board

    CERN Multimedia

    HR Department

    2008-01-01

    On 16 March and 7 May, the Pension Fund Governing Board (PFGB) held its fourth and fifth meetings The first of these meetings was primarily dedicated to the examination of the strategic asset allocation. The PFGB reaffirmed the main goal of the new strategic asset allocation: to improve the Pension Fund’s position with regard to risk by lowering overall portfolio volatility through suitable investments in less volatile asset classes such as real estate and absolute return strategies, where the return does not depend on market trends and negative growth is extremely unlikely. The finalised document will be presented to the Finance Committee and the Council at their June meetings for approval, in accordance with the provisions of the Levaux report. The PFGB also took note of the Internal Audit’s report on Pension Fund operations and decided to refer it to Working Group I as a working document for establishing a control and internal monitoring system for Pension Fund oper...

  7. Free-Piston Stirling Power Conversion Unit for Fission Power System, Phase II Final Report

    Science.gov (United States)

    Wood, J. Gary; Stanley, John

    2016-01-01

    In Phase II, the manufacture and testing of two 6-kW(sub e)Stirling engines was completed. The engines were delivered in an opposed 12-kW(sub e) arrangement with a common expansion space heater head. As described in the Phase I report, the engines were designed to be sealed both hermetically and with a bolted O-ring seal. The completed Phase II convertor is in the bolted configuration to allow future disassembly. By the end of Phase II, the convertor had passed all of the final testing requirements in preparation for delivery to the NASA Glenn Research Center. The electronic controller also was fabricated and tested during Phase II. The controller sets both piston amplitudes and maintains the phasing between them. It also sets the operating frequency of the machine. Details of the controller are described in the Phase I final report. Fabrication of the direct-current to direct-current (DC-DC) output stage, which would have stepped down the main controller output voltage from 700 to 120 V(sub DC), was omitted from this phase of the project for budgetary reasons. However, the main controller was successfully built, tested with the engines, and delivered. We experienced very few development issues with this high-power controller. The project extended significantly longer than originally planned because of yearly funding delays. The team also experienced several hardware difficulties along the development path. Most of these were related to the different thermal expansions of adjacent parts constructed of different materials. This issue was made worse by the large size of the machine. Thermal expansion problems also caused difficulties in the brazing of the opposed stainless steel sodium-potassium (NaK) heater head. Despite repeated attempts Sunpower was not able to successfully braze the opposed head under this project. Near the end of the project, Glenn fabricated an opposed Inconel NaK head, which was installed prior to delivery for testing at Glenn. Engine

  8. Risk analytics for hedge funds

    Science.gov (United States)

    Pareek, Ankur

    2005-05-01

    The rapid growth of the hedge fund industry presents significant business opportunity for the institutional investors particularly in the form of portfolio diversification. To facilitate this, there is a need to develop a new set of risk analytics for investments consisting of hedge funds, with the ultimate aim to create transparency in risk measurement without compromising the proprietary investment strategies of hedge funds. As well documented in the literature, use of dynamic options like strategies by most of the hedge funds make their returns highly non-normal with fat tails and high kurtosis, thus rendering Value at Risk (VaR) and other mean-variance analysis methods unsuitable for hedge fund risk quantification. This paper looks at some unique concerns for hedge fund risk management and will particularly concentrate on two approaches from physical world to model the non-linearities and dynamic correlations in hedge fund portfolio returns: Self Organizing Criticality (SOC) and Random Matrix Theory (RMT).Random Matrix Theory analyzes correlation matrix between different hedge fund styles and filters random noise from genuine correlations arising from interactions within the system. As seen in the results of portfolio risk analysis, it leads to a better portfolio risk forecastability and thus to optimum allocation of resources to different hedge fund styles. The results also prove the efficacy of self-organized criticality and implied portfolio correlation as a tool for risk management and style selection for portfolios of hedge funds, being particularly effective during non-linear market crashes.

  9. Computational Analysis of Igbo Numerals in a Number-to-text Conversion System

    Directory of Open Access Journals (Sweden)

    Olufemi Deborah NINAN

    2017-12-01

    Full Text Available System for converting Arabic numerals to their textual equivalence is an important tool in Natural Language processing (NLP especially in high-level speech processing and machine translation. Such system is scarcely available for most African languages including the Igbo language. This translation system is essential as Igbo language is one of the three major Nigerian languages feared to be among the endangered African languages. The system was designed using sequence as well as activity diagram and implemented using the python programming language and PyQt. The qualitative evaluation was done by administering questionnaires to selected native Igbo speakers and experts to provide preferred representation of some random numbers. The responses were compared with the output of the system. The result of the qualitative evaluation showed that the system was able to generate correct and accurate representations for Arabic numbers between 1-1000 in Igbo language being the scope of this study. The resulting system can serve as an effective teaching and learning tool of the Igbo language.

  10. Direct Conversion of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R

    1964-01-01

    Topics include: direct versus dynamic energy conversion; laws governing energy conversion; thermoelectricity; thermionic conversion; magnetohydrodynamic conversion; chemical batteries; the fuel cell; solar cells; nuclear batteries; and advanced concepts including ferroelectric conversion and thermomagnetic conversion.

  11. Multi-criteria assessment of energy conversion systems by means of thermodynamic, economic and environmental parameters

    Science.gov (United States)

    Becerra Lopez, Humberto Ruben

    2007-12-01

    High expansion of power demand is expected in the Upper Rio Grande region (El Paso, Hudspeth, Culberson, Jeff Davis, Presidio and Brewster counties) as a result of both electrical demand growth and decommissioning of installed capacity. On the supply side a notable deployment of renewable power technologies can be projected owing to the recent introduction of a new energy policy in Texas, which attempts to reach 10,000 installed-MWe of renewable capacity for 2025. Power generation fueled by natural-gas might consistently expand due to the encouraged use of this fuel. In this context the array of participating technologies can be optimized, which, within a sustainability framework, translates into a multidimensional problem. The solution to the problem is presented through this dissertation in two main parts. The first part solves the thermodynamic-environmental problem through developing a dynamic model to project maximum allowable expansion of technologies. Predetermined alternatives include diverse renewable energy technologies (wind turbine, photovoltaic conversion, hybrid solar thermal parabolic trough, and solid oxide fuel cells), a conventional fossil-fuel technology (natural gas combined-cycle), and a breakthrough fossil-fuel technology (solid oxide fuel cells). The analysis is based on the concept of cumulative exergy consumption, expanded to include abatement of emissions. A Gompertz sigmoid growth is assumed and constrained by both exergetic self-sustenance and regional energy resource availability. This part of the analysis assumes that power demand expansion is met by full deployment of alternative technologies backed up by conventional technology. Results show that through a proper allowance for exergy reinvestment the power demand expansion may be met largely by alternative technologies minimizing the primary resource depletion. The second part of the study makes use of the dynamic model to support a multi-objective optimization routine, where the

  12. Evaluation of the awareness and effectiveness of IT security programs in a large publicly funded health care system.

    Science.gov (United States)

    Hepp, Shelanne L; Tarraf, Rima C; Birney, Arden; Arain, Mubashir Aslam

    2017-01-01

    Electronic health records are becoming increasingly common in the health care industry. Although information technology (IT) poses many benefits to improving health care and ease of access to information, there are also security and privacy risks. Educating health care providers is necessary to ensure proper use of health information systems and IT and reduce undesirable outcomes. This study evaluated employees' awareness and perceptions of the effectiveness of two IT educational training modules within a large publicly funded health care system in Canada. Semi-structured interviews and focus groups included a variety of professional roles within the organisation. Participants also completed a brief demographic data sheet. With the consent of participants, all interviews and focus groups were audio recorded. Thematic analysis and descriptive statistics were used to evaluate the effectiveness of the IT security training modules. Five main themes emerged: (i) awareness of the IT training modules, (ii) the content of modules, (iii) staff perceptions about differences between IT security and privacy issues, (iv) common breaches of IT security and privacy, and (v) challenges and barriers to completing the training program. Overall, nonclinical staff were more likely to be aware of the training modules than were clinical staff. We found e-learning was a feasible way to educate a large number of employees. However, health care providers required a module on IT security and privacy that was relatable and applicable to their specific roles. Strategies to improve staff education and mitigate against IT security and privacy risks are discussed. Future research should focus on integrating health IT competencies into the educational programs for health care professionals.

  13. CONKUB: A Conversational Path-Follower for Systems of Nonlinear Equations

    Science.gov (United States)

    Mejia, R.

    1986-03-01

    We describe an interactive computer program to trace solutions of systems of nonlinear algebraic equations and illustrate its application to solve several difficult problems. Turning points and bifurcations are located and solution branches are identified and traced interactively. Of special interest is its application to study solutions of large, sparse systems of non-linear equations that result from the discretization of boundary value problems. Such systems arise in the description of physical, biological, and chemical phenomena. As an example, we show a model of urine formation in the mammalian kidney [13], where path-following in a subspace makes tracing the solution surface possible.

  14. Ocean thermal energy conversion (OTEC). Power system development. Preliminary design report, final

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-04

    The preliminary design of the 10 MWe OTEC power module and the 200 kWe test articles is given in detail. System operation and performance; power system cost estimates; 10 MWe heat exchangers; 200 kWe heat exchanger articles; biofouling control;ammonia leak detection, and leak repair; rotating machinery; support subsystem; instrumentation and control; electrical subsystem; installation approach; net energy and resource analysis; and operability, maintainability, and safety are discussed. The conceptual design of the 40 MWe electrical power system includes four or five 10 MWe modules as designed for the 10 MWe pilot plant. (WHK)

  15. Second order sliding power control for a variable speed-constant frequency energy conversion system

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, Fernando, E-mail: fval@ing.unlp.edu.a [CONICET, Laboratorio de Electronica Industrial Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, CC.91, C.P. 1900 La Plata (Argentina)

    2010-12-15

    This paper presents a decoupled active and reactive power control for a variable speed-constant frequency generation system based on a brushless doubly fed reluctance machine. The control design is approached using multi-input second order sliding techniques which are specially appropriate to deal with nonlinear system models in presence of external disturbances and model inaccuracies. The controller synthesized through this theoretical framework presents very good robustness features, a finite reaching time and a chattering-free behavior. The performance of the closed loop system is assessed through representative computer simulations.

  16. Perspective and investments in health system strengthening of Gavi, the Vaccine Alliance: a content analysis of health system strengthening-specific funding.

    Science.gov (United States)

    Tsai, Feng-Jen; Lee, Howard; Fan, Victoria Y

    2016-07-01

    This paper aimed to compare the health systems strengthening (HSS) framework of Gavi and WHO and to analyze resource allocation in HSS by Gavi. Among 76 countries which received HSS funding from Gavi from 2006 to 2013, summary reports of 44 countries and approved proposals of 10 countries were collected. After comparing the HSS framework of WHO and Gavi, each activity described in documents was categorized according to Gavi's framework and funding allocation was analyzed. Compared with WHO's HSS framework, Gavi's has a distinctive function within the building block 'Drugs, Equipment, Supplies, Facilities' and a distinctive function of 'providing incentive and bonuses' under the building block 'Human Resource/Performance Management'. Gavi has steadily invested 10% of their total budget on HSS, but 47% were allocated in these categories, whereas 78% were for activities arguably not covered by WHO's HSS framework. In Africa, 70% of Gavi's budget fell under 'Drugs, Equipment, Supplies, Facilities' and 92.8% were for activities arguably not deemed as HSS by WHO. Gavi's HSS support emphasized inputs with short-term measurable outcomes. Harmonization of the concept of HSS and collaboration between Gavi and multilateral international agencies, such as World Bank and WHO, are needed. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Laser energy conversion

    Science.gov (United States)

    Jalufka, N. W.

    1989-01-01

    The conversion of laser energy to other, more useful, forms is an important element of any space power transmission system employing lasers. In general the user, at the receiving sight, will require the energy in a form other than laser radiation. In particular, conversion to rocket power and electricity are considered to be two major areas where one must consider various conversion techniques. Three systems (photovoltaic cells, MHD generators, and gas turbines) have been identified as the laser-to-electricity conversion systems that appear to meet most of the criteria for a space-based system. The laser thruster also shows considerable promise as a space propulsion system. At this time one cannot predict which of the three laser-to-electric converters will be best suited to particular mission needs. All three systems have some particular advantages, as well as disadvantages. It would be prudent to continue research on all three systems, as well as the laser rocket thruster. Research on novel energy conversion systems, such as the optical rectenna and the reverse free-electron laser, should continue due to their potential for high payoff.

  18. Uncertainties in Classification System Conversion and an Analysis of Inconsistencies in Global Land Cover Products

    National Research Council Canada - National Science Library

    Miao Zhang; Mingguo Ma; Philippe De Maeyer; Alishir Kurban

    2017-01-01

    ... (vegetation, wetlands and others only), we studied spatial and areal inconsistencies in the three most recent multi-resource land cover products in a complex mountain-oasis-desert system and quantitatively discussed the uncertainties...

  19. Novel, Integrated Reactor/Power Conversion System. Quarterly Report, September 1 - November 30, 1999

    Energy Technology Data Exchange (ETDEWEB)

    None

    1999-12-06

    The desired design objectives and operation parameters were determined and system characteristics to be investigated were identified together with critical issues. Specific tasks were outlined and communicated to the performing personnel.

  20. Demonstration of Silicon Carbide Power Devices in Practical Power Conversion Systems

    National Research Council Canada - National Science Library

    Cooper, James A., Jr; Sudhoff, Scott D; Kwon, C; Glover, S. F

    2005-01-01

    ...) with blocking voltages above 1,000 V and on-state currents above 25 A; (2) to fabricate and package sufficient quantities of these devices to implement a demonstration motor control system; (3...

  1. Proceedings of the third biennial conference and workshop on wind energy conversion systems. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Kornreich, T R [ed.

    1978-05-01

    Separate abstracts are included for 34 papers presented concerning technology development, meteorological siting considerations, multi-unit applications, and innovative and advanced systems concepts. Two papers were previously input into the energy data base.

  2. Variable-speed wind power system with improved energy capture via multilevel conversion

    Science.gov (United States)

    Erickson, Robert W.; Al-Naseem, Osama A.; Fingersh, Lee Jay

    2005-05-31

    A system and method for efficiently capturing electrical energy from a variable-speed generator are disclosed. The system includes a matrix converter using full-bridge, multilevel switch cells, in which semiconductor devices are clamped to a known constant DC voltage of a capacitor. The multilevel matrix converter is capable of generating multilevel voltage wave waveform of arbitrary magnitude and frequencies. The matrix converter can be controlled by using space vector modulation.

  3. Develop the dual fuel conversion system for high output, medium speed diesel engines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-16

    The original plan for the project involved design modifications to an existing system to enhance its performance and increase the limit of power that was achieved by the original design and to apply the higher performance product to the full sized engine and test its performance. The new system would also be applied to a different engine model. The specific work would include the redesign of gas injectors, piston configurations and two types of igniters, engine instrumentation, monitoring and testing.

  4. Advanced Control of Permanent Magnet Synchronous Generators for Variable Speed Wind Energy Conversion Systems

    Science.gov (United States)

    Hostettler, Jacob

    Various environmental and economic factors have lead to increased global investment in alternative energy technologies such as solar and wind power. Although methodologies for synchronous generator control are well researched, wind turbines present control systems challenges not presented by traditional generation. The varying nature of wind makes achieving synchronism with the existing electrical power grid a greater challenge. Departing from early use of induction machines, permanent magnet synchronous generators have become the focus of power systems and control systems research into wind energy systems. This is due to their self excited nature, along with their high power density. The problem of grid synchronism is alleviated through the use of high performance power electronic converters. In achievement of the optimal levels of efficiency, advanced control systems techniques oer promise over more traditional approaches. Research into sliding mode control, and linear matrix inequalities with nite time boundedness and Hinfinity performance criteria, when applied to the dynamical models of the system, demonstrate the potential of these control methodologies as future avenues for achieving higher levels of performance and eciency in wind energy.

  5. Information on the Conversion of the Rental Contract of the Siemens 7.880 System into a Purchase Contract and Request for Approval to Purchase, without a Call for Tenders, Peripheral Equipment compatible with this system

    CERN Document Server

    1982-01-01

    Information on the Conversion of the Rental Contract of the Siemens 7.880 System into a Purchase Contract and Request for Approval to Purchase, without a Call for Tenders, Peripheral Equipment compatible with this system

  6. Systems Based Approaches for Thermochemical Conversion of Biomass to Bioenergy and Bioproducts

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Steven [Auburn Univ., AL (United States)

    2016-07-11

    Auburn’s Center for Bioenergy and Bioproducts conducts research on production of synthesis gas for use in power generation and the production of liquid fuels. The overall goal of our gasification research is to identify optimal processes for producing clean syngas to use in production of fuels and chemicals from underutilized agricultural and forest biomass feedstocks. This project focused on construction and commissioning of a bubbling-bed fluidized-bed gasifier and subsequent shakedown of the gasification and gas cleanup system. The result of this project is a fully commissioned gasification laboratory that is conducting testing on agricultural and forest biomass. Initial tests on forest biomass have served as the foundation for follow-up studies on gasification under a more extensive range of temperatures, pressures, and oxidant conditions. The laboratory gasification system consists of a biomass storage tank capable of holding up to 6 tons of biomass; a biomass feeding system, with loss-in-weight metering system, capable of feeding biomass at pressures up to 650 psig; a bubbling-bed fluidized-bed gasification reactor capable of operating at pressures up to 650 psig and temperatures of 1500oF with biomass flowrates of 80 lb/hr and syngas production rates of 37 scfm; a warm-gas filtration system; fixed bed reactors for gas conditioning; and a final quench cooling system and activated carbon filtration system for gas conditioning prior to routing to Fischer-Tropsch reactors, or storage, or venting. This completed laboratory enables research to help develop economically feasible technologies for production of biomass-derived synthesis gases that will be used for clean, renewable power generation and for production of liquid transportation fuels. Moreover, this research program provides the infrastructure to educate the next generation of engineers and scientists needed to implement these technologies.

  7. Vulnerability of pension fund balances

    Directory of Open Access Journals (Sweden)

    Ólafur Ísleifsson

    2012-12-01

    Full Text Available Although the Icelandic general labour market pension funds are built on the proviso that pension schemes are fully funded these funds are still grappling with the devastating financial effects of the 2008 economic collapse that rendered most of them in a significant actuarial deficit. The public sector pension funds are based on an employer guarantee that makes up for any lack of funding that historically has been quite significant. We identify the relatively high actuarial discount rate and increasing longevity as two factors that add to the vulnerability of the Icelandic pension system. We present a stochastic model in order to obtain reasonably sound estimates of the effect of revising such key parameters of the actuarial assessments of the pension funds and thus obtain a view of the viability of the Icelandic pension system when confronted with the potential necessity of such parameter shifts. We present results of stochastic simulations of this models made to assess effects of changes in these major financial and demographic assumptions in actuarial evaluations of pension fund balances. Our results suggest that the Icelandic pension funds may be significantly less well funded than is generally perceived.

  8. A Neural Network Controller for Variable-Speed Variable-Pitch Wind Energy Conversion Systems Using Generalized Minimum Entropy Criterion

    Directory of Open Access Journals (Sweden)

    Mifeng Ren

    2014-01-01

    Full Text Available This paper considers the neural network controller design problem for variable pitch wind energy conversion systems (WECS with non-Gaussian wind speed disturbances in the stochastic distribution control framework. The approach here is used to directly model the unknown control law based on a fixed neural network (the number of layers and nodes in a neural network is fixed without the need to construct a separate model for the WECS. In order to characterize the randomness of the WECS, a generalized minimum entropy criterion is established to train connection weights of the neural network. For the train purpose, both kernel density estimation method and sliding window technique are adopted to estimate the PDF of tracking error and entropies. Due to the unknown process dynamics, the gradient of the objective function in a gradient-descent-type algorithm is estimated using an incremental perturbation method. The proposed approach is illustrated on a simulated WECS with non-Gaussian wind speed.

  9. High-temperature corrosion and applications of nickel and iron aluminides in coal-conversion power systems

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K. [Argonne National Lab., IL (United States); Tortorelli, P.F. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    Nickel and iron aluminide intermetallics are being developed for use as structural materials and/or as cladding for conventional engineering alloys. In addition to strength advantages, these materials exhibit excellent resistance to corrosion in single- and multioxidant environments at elevated temperatures by the formation of slow-growing, adherent alumina scales. Corrosion resistance in a given environment is strongly dependent on the composition of the alloy and on the nature of the corrosive species prevalent in the service environment. This paper presents a comprehensive review of the current status of the corrosion performance of these intermetallics in oxidizing, sulfidizing, and multicomponent gas environments of typical coal-conversion systems. Mechanisms of scale development/breakdown, performance envelopes for long-term usage of these materials, approaches to modifying the surfaces of engineering alloys by cladding or coating them with intermetallics, and in-service experience with these materials are emphasized.

  10. Model Predictive Control-based Power take-off Control of an Oscillating Water Column Wave Energy Conversion System

    Science.gov (United States)

    Rajapakse, G.; Jayasinghe, S. G.; Fleming, A.; Shahnia, F.

    2017-07-01

    Australia’s extended coastline asserts abundance of wave and tidal power. The predictability of these energy sources and their proximity to cities and towns make them more desirable. Several tidal current turbine and ocean wave energy conversion projects have already been planned in the coastline of southern Australia. Some of these projects use air turbine technology with air driven turbines to harvest the energy from an oscillating water column. This study focuses on the power take-off control of a single stage unidirectional oscillating water column air turbine generator system, and proposes a model predictive control-based speed controller for the generator-turbine assembly. The proposed method is verified with simulation results that show the efficacy of the controller in extracting power from the turbine while maintaining the speed at the desired level.

  11. Model for energy conversion in renewable energy system with hydrogen storage

    Science.gov (United States)

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

    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.

  12. Proportional Systems in the History of Architecture: A Conversation with James S. Ackerman

    Directory of Open Access Journals (Sweden)

    Matthew A Cohen

    2014-06-01

    Full Text Available In November 2010, James S. Ackerman, today the only living participant of the conference ‘De divina proportione’, which was held in Milan in 1951, sat for a video interview that was later shown at the conference ‘Proportional Systems in the History of Architecture’ in Leiden in 2011 to mark the sixtieth anniversary of the Milan conference. In this interview, conducted by Matthew A. Cohen, Ackerman discusses how the study of proportional systems has changed over the past six decades, and thereby provides a unique link between the two conferences. The interview begins with Ackerman’s experiences in northern Italy at the close of World War II, and a few years later at the Milan conference. It considers prevailing twentieth-century attitudes toward proportion up to the time of the conference, and compares them with prevailing medieval and Renaissance attitudes. Ackerman then shares his thoughts on the works and legacies of Rudolf Wittkower, Le Corbusier and Colin Rowe, before exploring the influences of architectural proportional theory on architectural design, and possible relationships between proportional systems and architectural beauty. After exploring changes in the uses of proportional systems that accompanied the rise of Abstract Expressionism, the arc of the interview concludes with Ackerman’s thoughts about the future of proportional systems in light of the evolving role of the computer in architectural practice today.

  13. Ocean thermal energy conversion (OTEC) power system development. Preliminary design report, Appendices, Part 1 (Final)

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-04

    The objective of this project is the development of a preliminary design for a full-sized, closed cycle, ammonia power system module for the 100 MWe OTEC demonstration plant. In turn, this demonstration plant is to demonstrate, by 1984, the operation and performance of an Ocean Thermal Power Plant having sufficiently advanced heat exchanger design to project economic viability for commercial utilization in the late 1980's and beyond. Included in this power system development are the preliminary designs for a proof-of-concept pilot plant and test article heat exchangers which are scaled in such a manner as to support a logically sequential, relatively low-cost development of the full-scale power system module. The conceptual designs are presented for the demonstration plant power module, the proof-of-concept pilot plant, and for a pair of test article heat exchangers. Costs associated with the design, development, fabrication, checkout, delivery, installation, and operation are included. The accompanying design and producibilty studies on the full-scale power system module project the performance/economics for the commercial plant. This section of the report contains appendices on the developed computer models, water system dynamic studies, miscellaneous performance analysis, materials and processes, detailed equipment lists, turbine design studies, tube cleaner design, ammonia leak detection, and heat exchanger design supporting data. (WHK)

  14. Power system development: Ocean Thermal Energy Conversion (OTEC). Preliminary design report: appendices, Part 2 (Final)

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-12-04

    The objective of this project is the development of a preliminary design for a full-sized, closed cycle, ammonia power system module for the 100 MWe OTEC demonstration plant. In turn, this demonstration plant is to demonstrate, by 1984, the operation and performance of an Ocean Thermal Power Plant having sufficiently advanced heat exchanger design to project economic viability for commercial utilization in the late 1980's and beyond. Included in this power system development are the preliminary designs for a proof-of-concept pilot plant and test article heat exchangers which are scaled in such a manner as to support a logically sequential, relatively low-cost development of the full-scale power system module. The conceptual designs are presented for the demonstration plant power module, the proof-of-concept pilot plant, and for a pair of test article heat exchangers. Costs associated with the design, development, fabrication, checkout, delivery, installation, and operation are included. The accompanying design and producibilty studies on the full-scale power system module project the performance/economics for the commercial plant. This section of the report contains appendices on the electrical system, instrumentation and control, ammonia pump evaluation study, ammonia and nitrogen support subsystems, piping and support design calculations, and plant availability. (WHK)

  15. Efficient Photocurrent Enhancement from Porphyrin Molecules on Plasmonic Copper Arrays: Beneficial Utilization of Copper Nanoanntenae on Plasmonic Photoelectric Conversion Systems.

    Science.gov (United States)

    Sugawa, Kosuke; Yamaguchi, Daisuke; Tsunenari, Natsumi; Uchida, Koji; Tahara, Hironobu; Takeda, Hideyuki; Tokuda, Kyo; Jin, Shota; Kusaka, Yasuyuki; Fukuda, Nobuko; Ushijima, Hirobumi; Akiyama, Tsuyoshi; Watanuki, Yasuhiro; Nishimiya, Nobuyuki; Otsuki, Joe; Yamada, Sunao

    2017-01-11

    We demonstrated the usefulness of Cu light-harvesting plasmonic nanoantennae for the development of inexpensive and efficient artificial organic photoelectric conversion systems. The systems consisted of the stacked structures of layers of porphyrin as a dye molecule, oxidation-suppressing layers, and plasmonic Cu arrayed electrodes. To accurately evaluate the effect of Cu nanoantenna on the porphyrin photocurrent, the production of Cu2O by the spontaneous oxidation of the electrode surfaces, which can act as a photoexcited species under visible light irradiation, was effectively suppressed by inserting the ultrathin linking layers consisting of 16-mercaptohexadecanoic acid, titanium oxide, and poly(vinyl alcohol) between the electrode surface and porphyrin molecules. The reflection spectra in an aqueous environment of the arrayed electrodes, which were prepared by thermally depositing Cu on two-dimensional colloidal crystals of silica with diameters of 160, 260, and 330 nm, showed clear reflection dips at 596, 703, and 762 nm, respectively, which are attributed to the excitation of localized surface plasmon resonance (LSPR). While the first dip lies within the wavelengths where the imaginary part of the Cu dielectric function is moderately large, the latter two dips lie within a region of a quite small imaginary part. Consequently, the LSPR excited at the red region provided a particularly large enhancement of porphyrin photocurrent at the Q-band (ca. 59-fold), compared to that on a Cu planar electrode. These results strongly suggest that the plasmonic Cu nanoantennae contribute to the substantial improvement of photoelectric conversion efficiency at the wavelengths, where the imaginary part of the dielectric function is small.

  16. Design of a system for conversion of gyrotron output into a gaussian beam

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, I. [Faculty of Engineering, Fukui Univ., Fukui (Japan); Idehara, T.; Sabchevski, S.; Glyavin, M.; Mitsudo, S. [Research Center for Development of Far-Infrared Region, Fukui Univ., Fukui (Japan); Sato, M.; Kawahata, K. [National Inst. for Fusion Science, Toki, Gifu (Japan); Brand, G.F. [School of Physics, Univ. of Sydney, NSW (Australia)

    2000-03-01

    A quasi-optical system consisting of a quasi-optical antenna, two ellipsoidal mirrors and a filter to block sidelobes can convert four TE{sub 1n} mode outputs of the Gyrotron FU IVA into gaussian-like beams with waist size of 16.3 mm. This system can convert three TE{sub 0n} mode outputs into bigaussian-like beams with waist size of 23.5 mm in width and 16.4 mm in length. (author)

  17. Micro/Nano-Scale Phase Change Systems for Thermal Management and Solar Energy Conversion Applications

    Science.gov (United States)

    Coso, Dusan

    The first part of the dissertation presents a study that implements micro and nano scale engineered surfaces for enhancement of evaporation and boiling phase change heat transfer in both capillary wick structures and pool boiling systems. Capillary wicking surfaces are integral components of heat pipes and vapor chamber thermal spreaders often used for thermal management of microelectronic devices. In addition, pool boiling systems can be encountered in immersion cooling systems which are becoming more commonly investigated for thermal management applications of microelectronic devices and even data centers. The latent heat associated with the change of state from liquid to vapor, and the small temperature differences required to drive this process yield great heat transfer characteristics. Additionally, since no external energy is required to drive the phase change process, these systems are great for portable devices and favorable for reduction of cost and energy consumption over alternate thermal management technologies. Most state of the art capillary wicks used in these devices are typically constructed from sintered copper media. These porous structures yield high surface areas of thin liquid film where evaporation occurs, thus promoting phase change heat transfer. However, thermal interfaces at particle point contacts formed during the sintering process and complex liquid/vapor flow within these wick structures yield high thermal and liquid flow resistances and limit the maximum heat flux they can dissipate. In capillary wicks the maximum heat flux is typically governed by the capillary or boiling limits and engineering surfaces that delay these limitations and yield structures with large surface areas of thin liquid film where phase change heat transfer is promoted is highly desired. In this study, biporous media consisting of microscale pin fins separated by microchannels are examined as candidate structures for the evaporator wick of a vapor chamber heat

  18. Converse Barrier Certificate Theorems

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2016-01-01

    This paper shows that a barrier certificate exists for any safe dynamical system. Specifically, we prove converse barrier certificate theorems for a class of structurally stable dynamical systems. Other authors have developed a related result by assuming that the dynamical system has neither...... singular points nor closed orbits. In this paper, we redefine the standard notion of safety to comply with dynamical systems with multiple singular elements. Hereafter, we prove the converse barrier certificate theorems and highlight the differences between our results and previous work by a number...

  19. Converse Barrier Certificate Theorem

    DEFF Research Database (Denmark)

    Wisniewski, Rafael; Sloth, Christoffer

    2013-01-01

    This paper presents a converse barrier certificate theorem for a generic dynamical system.We show that a barrier certificate exists for any safe dynamical system defined on a compact manifold. Other authors have developed a related result, by assuming that the dynamical system has no singular...... points in the considered subset of the state space. In this paper, we redefine the standard notion of safety to comply with generic dynamical systems with multiple singularities. Afterwards, we prove the converse barrier certificate theorem and illustrate the differences between ours and previous work...

  20. A Fast linking approach for CMYK to CMYK conversion preserving black separation in ICC color management system

    Science.gov (United States)

    Zeng, Huanzhao

    2003-12-01

    In the linking step of the standard ICC color management workflow for CMYK to CMYK conversion, a CMM takes an AToBn tag (n = 0, 1, or 2) from a source ICC profile to convert a color from the source color space to PCS (profile connection space), and then takes a BToAn tag from the destination ICC profile to convert the color from PCS to the destination color space. This approach may give satisfactory result perceptually or colorimetrically. However, it does not preserve the K channel for CMYK to CMYK conversion, which is often required in graphic art"s market. The problem is that the structure of a BtoAn tag is designed to convert colors from PCS to a device color space ignoring the K values from the source color space. Different approaches have been developed to control K in CMYK to CMYK printing, yet none of them well fits into the "Profile - PCS - Profile" model in the ICC color management system. A traditional approach is to transform the source CMYK to the destination CMYK by 1-D TRC curves and GCR/UCR tables. This method is so simple that it cannot accurately transform colors perceptually or colorimetrically. Another method is to build a 4-D CMYK to CMYK closed-loop lookup table (LUT) (or a deviceLink ICC profile) for the color transformation. However, this approach does not fit into opened color management workflows for it ties the source and the destination color spaces in the color characterization step. A specialized CMM may preserve K for a limit number of colors by mapping those CMYK colors to some carefully chosen PCS colors in both the AToBi tag and the BToAi tag. A more complete solution is to move to smart linking in which gamut mapping is performed in the real-time linking at a CMM. This method seems to solve all problems existed in the CMYK to CMYK conversion. However, it introduces new problems: 1) gamut mapping at real-time linking is often unacceptable slow; 2) gamut mapping may not be optimized or may be unreliable; 3) manual adjustment for

  1. Determining the Optimal Capacities of Renewable-Energy-Based Energy Conversion Systems for Meeting the Demands of Low-Energy District Heating, Electricity, and District Cooling

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend; Dincer, Ibrahim

    2015-01-01

    This chapter presents a method for determining the optimal capacity of a renewable-energy-based energy conversion system for meeting the energy requirements of a given district as considered on a monthly basis, with use of a low-energy district heating system operating at a low temperature, as low......, and the other for the Greater Toronto Area. Various climate conditions of the case areas in question caused different observations of nominal capacities for the energy conversion systems considered with single-production and multi-production based on different renewable energy sources....

  2. Pension fund

    CERN Multimedia

    Staff Association

    2014-01-01

    Letter sent on Monday 8 December 2014 to the delegates of the Member States to CERN Council An item on the agenda of the CERN Council of Thursday 11 December concerned the CERN Pension Fund, namely a discussion of a document that proposes how to respond to the many questions concerning pensions that had been submitted by thirteen Member State delegations. That document lists all these questions and proposes, as a first step, to consider the legal feasibility and the actuarial cost to transform our current defined-benefit pension scheme into a defined-contribution scheme. Once again, several delegates show their determination to worsen our pension conditions. The Staff Association’s Pension Commission, in a special meeting on Thursday, 4 December, has decided to send an open letter to the delegates of the CERN Council. In this letter (shown below) the Staff Association and CERN-ESO Pensions’ Association express their opposition to these intentions. We underline, once more, that the 2010...

  3. DEVELOPMENT OF AUTOMATED SPEECH RECOGNITION SYSTEM FOR EGYPTIAN ARABIC PHONE CONVERSATIONS

    Directory of Open Access Journals (Sweden)

    A. N. Romanenko

    2016-07-01

    Full Text Available The paper deals with description of several speech recognition systems for the Egyptian Colloquial Arabic. The research is based on the CALLHOME Egyptian corpus. The description of both systems, classic: based on Hidden Markov and Gaussian Mixture Models, and state-of-the-art: deep neural network acoustic models is given. We have demonstrated the contribution from the usage of speaker-dependent bottleneck features; for their extraction three extractors based on neural networks were trained. For their training three datasets in several languageswere used:Russian, English and differentArabic dialects.We have studied the possibility of application of a small Modern Standard Arabic (MSA corpus to derive phonetic transcriptions. The experiments have shown that application of the extractor obtained on the basis of the Russian dataset enables to increase significantly the quality of the Arabic speech recognition. We have also stated that the usage of phonetic transcriptions based on modern standard Arabic decreases recognition quality. Nevertheless, system operation results remain applicable in practice. In addition, we have carried out the study of obtained models application for the keywords searching problem solution. The systems obtained demonstrate good results as compared to those published before. Some ways to improve speech recognition are offered.

  4. Systems and processes for conversion of ethylene feedstocks to hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, Michael A.; Hallen, Richard T.; Albrecht, Karl O.; Cooper, Alan R.; Frye, John G.; Ramasamy, Karthikeyan Kallupalayam

    2017-09-26

    Systems, processes, and catalysts are disclosed for obtaining fuels and fuel blends containing selected ratios of open-chain and closed-chain fuel-range hydrocarbons suitable for production of alternate fuels including gasolines, jet fuels, and diesel fuels. Fuel-range hydrocarbons may be derived from ethylene-containing feedstocks and ethanol-containing feedstocks.

  5. A THERMAL-HYDRAULIC SYSTEM FOR THE CONVERSION AND THE STORAGE OF ENERGY

    OpenAIRE

    MITRAN Tudor; CHIOREANU Nicolae; ABAITANCAI Horia; RUS Alexandru

    2016-01-01

    The paper proposes the concept design of a thermal-hydraulic system that converts the thermal energy (from the geothermal water, from the cooling water of power equipment, from exhaust gasses, and so.) in hydrostatic energy, that is stored in a hydraulic accumulator. The hydraulic energy can be converted into electrical energy when needed.

  6. A THERMAL-HYDRAULIC SYSTEM FOR THE CONVERSION AND THE STORAGE OF ENERGY

    Directory of Open Access Journals (Sweden)

    MITRAN Tudor

    2016-05-01

    Full Text Available The paper proposes the concept design of a thermal-hydraulic system that converts the thermal energy (from the geothermal water, from the cooling water of power equipment, from exhaust gasses, and so. in hydrostatic energy, that is stored in a hydraulic accumulator. The hydraulic energy can be converted into electrical energy when needed.

  7. Systems and processes for conversion of ethylene feedstocks to hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, Michael A.; Hallen, Richard T.; Albrecht, Karl O.; Cooper, Alan R.; Frye, John G.; Ramasamy, Karthikeyan Kallupalayam

    2017-05-30

    Systems, processes, and catalysts are disclosed for obtaining fuel and fuel blends containing selected ratios of open-chain and closed-chain fuel-range hydrocarbons suitable for production of alternate fuels including gasolines, jet fuels, and diesel fuels. Fuel-range hydrocarbons may be derived from ethylene-containing feedstocks and ethanol-containing feedstocks.

  8. Convincing Conversations : Using a Computer-Based Dialogue System to Promote a Plant-Based Diet

    NARCIS (Netherlands)

    Zaal, Emma; Mills, Gregory; Hagen, Afke; Huisman, Carlijn; Hoeks, Jacobus

    2017-01-01

    In this study, we tested the effectiveness of a computer-based persuasive dialogue system designed to promote a plant-based diet. The production and consumption of meat and dairy has been shown to be a major cause of climate change and a threat to public health, bio-diversity, animal rights and

  9. Design methodology for flexible energy conversion systems accounting for dynamic performance

    DEFF Research Database (Denmark)

    Pierobon, Leonardo; Casati, Emiliano; Casella, Francesco

    2014-01-01

    of power systems for base- and part-load operation. Thus, it is crucial to discard, in an early phase of the design process, plant configurations which feature unacceptable dynamic performance. The test case is the preliminary design of an off-grid power plant serving an off-shore platform where one...

  10. The economics of a mechanized multiproduct harvesting system for stand conversion of northern hardwoods.

    Science.gov (United States)

    John A. Sturos; Edwin S. Miyata; Helmuth M. Steinhilb; Robert M. Barron

    1983-01-01

    Describes chip and saw log yields, production, costs, and potential profits of clearcutting, down to a 2-inch diameter, a northern hardwood poletimber stand by a conventional whole-tree harvesting system and three sawtimber stands by several combinations of whole-tree chipping and saw log recovery.

  11. Investing in Their Future: Portland’s Purchase and Conversion of an LED Street Lighting System

    Energy Technology Data Exchange (ETDEWEB)

    Kinzey, B. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rosinbum, T. [Portland Bureau of Transportation, Portland, OR (United States)

    2015-08-28

    During the ongoing process of converting its streetlights from high-pressure sodium to LED, the city of Portland, Oregon, purchased a large portion of its street lighting system and encountered a range of issues among the stakeholders. This report identifies some of the challenges involved and discusses how they were addressed, in order to help inform and facilitate future lighting transitions elsewhere.

  12. Ocean thermal energy conversion power system development-I. Phase I. Preliminary design report. Volume 1. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-18

    The results of a conceptual and preliminary design study of Ocean Thermal Energy Conversion (OTEC) closed loop ammonia power system modules performed by Lockheed Missiles and Space Company, Inc. (LMSC) are presented. This design study is the second of 3 tasks in Phase I of the Power System Development-I Project. The Task 2 objectives were to develop: 1) conceptual designs for a 40 to 50-MW(e) closed cycle ammonia commercial plant size power module whose heat exchangers are immersed in seawater and whose ancillary equipments are in a shirt sleeve environment; preliminary designs for a modular application power system sized at 10-MW(e) whose design, construction and material selection is analogous to the 50 MW(e) module, except that titanium tubes are to be used in the heat exchangers; and 3) preliminary designs for heat exchanger test articles (evaporator and condenser) representative of the 50-MW(e) heat exchangers using aluminum alloy, suitable for seawater service, for testing on OTEC-1. The reference ocean platform was specified by DOE as a surface vessel with the heat exchanger immersed in seawater to a design depth of 0 to 20 ft measured from the top of the heat exchanger. For the 50-MW(e) module, the OTEC 400-MW(e) Plant Ship, defined in the Platform Configuration and Integration study, was used as the reference platform. System design, performance, and cost are presented. (WHK)

  13. Phase 1: conceptual design. Ocean thermal energy conversion power system development. Volume 2 of 3. Technical details. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-30

    Westinghouse has completed the conceptual design of the Power System for the Ocean Thermal Energy Conversion (OTEC) Demonstration Plant project. This study included the development of a conceptual design for the following three items: first, a full-size power system module for the 100 MWe Demonstration Plant; second, a scaled proof of concept power system; and third, a heat exchanger test article. The study was limited to a closed cycle ammonia power system module, using a water temperature difference of 40/sup 0/F., and a surface platform/ship reference hull. Two power module of 50 MWe each are recommended for the demonstration plant. The 50 MWe module was selected since it has the lowest cost, and since it is of a size which convincingly demonstrates that future economically viable commercial plants, having reliable operation with credible anticipated costs, are possible. A modular, tube bundle approach to heat exchanger design makes large heat exchangers practical and economical. Other power module elements are considered to be within state-of-practice. Technological assessments of all subsystems indicate requirements for verification only, rather than continued research. A complete test program, which will verify the mechanical reliability as well as thermal performance, is recommended.

  14. Design, simulation, analysis and optimization of transportation system for a biomass to ethanol conversion plant

    Science.gov (United States)

    Ravula, Poorna P.

    The US Department of Energy has set an ambitious goal of replacing 30% of current petroleum consumption with biomass and its products by the year 2030. To achieve this goal, various systems capable of handling biomass at this magnitude have to be designed and built. The transportation system for a cotton gin was studied and modeled with the current management policy (FIFO) used by the gin to gain understanding of a logistic system where the processing plant (gin) pays for the transportation of the feedstock. Alternate management policies for transporting cotton modules showed significant time savings of 24% in days-to-haul. To design a logistics system and management strategy that will minimize the cost of biomass delivery (round bales of switchgrass), a seven-county region in southern Piedmont region of Virginia was selected as the location for a 50 Mg/h bioprocessing plant which operates 24 h/day, 7 days/week. Some of the equipment are not be commercially available and need to be developed. The transport equipment (trucks, loaders and unloaders) was defined and the operational parameters estimated. One hundred and fifty-five secondary storage locations (SSLs) along with a 3.2-km procurement area for each SSL were determined for the region. The travel time from each SSL to the plant was calculated based on a network flow analysis. Seven different policies (strategies) for scheduling loaders were studied. The two key variables were maximum number of trucks required and the maximum at-plant inventory. Five policies were based on "Shortest Travel Time - Longest Travel Time" allocation and two policies were based on "Sector-based" allocation. Policies generating schedules with minimum truck requirement and at-plant storage were simulated. A discrete event simulation model for the logistic system was constructed and the productive operating times for system equipment and inventory was computed. Lowest delivered cost was 14.68/Mg with truck cost averaging 8.44/Mg and

  15. Conversion to Resection in Patients Receiving Systemic Chemotherapy for Unresectable and/or Metastatic Colorectal Cancer-Predictive Factors and Prognosis.

    Science.gov (United States)

    Nozawa, Hiroaki; Ishihara, Soichiro; Kawai, Kazushige; Hata, Keisuke; Kiyomatsu, Tomomichi; Tanaka, Toshiaki; Nishikawa, Takeshi; Otani, Kensuke; Yasuda, Koji; Sasaki, Kazuhito; Kaneko, Manabu; Murono, Koji

    2017-10-19

    Systemic chemotherapy increases the possibility of resection in patients with initially unresectable colorectal cancer (CRC), especially patients with hepatic metastasis. However, the predictive factors and prognosis of conversion to resection after chemotherapy in patients with various organ metastases remain largely unknown. We reviewed the data from metastatic CRC (mCRC) patients who had received oxaliplatin- or irinotecan-based systemic chemotherapy from 2005 to 2016. The predictors for conversion to surgery were assessed by multivariate analyses. Cancer-free survival and overall survival after the initiation of treatment were compared between patients who had undergone successful conversion therapy and those who had undergone surgery first for resectable stage IV CRC. Of 99 mCRC patients receiving first-line chemotherapy, 23 underwent secondary surgical resection. Single organ metastasis, the presence of liver metastases, and the use of biologic agents were independent predictors of successful conversion therapy. The long-term survival of patients who underwent successful secondary surgery did not differ significantly from that of the 112 patients with resectable stage IV CRC who had undergone surgery first. Liver metastases and single organ metastasis were more likely to be resected after chemotherapy than were other metastatic lesions in mCRC. The use of biologic agents contributed to the increased conversion rate. Successful conversion resulted in outcomes similar to those of resectable stage IV CRC. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Did the first Global Fund grant (2003–2006) contribute to malaria control and health system strengthening in Timor-Leste?

    Science.gov (United States)

    2012-01-01

    Background In 2003, Timor-Leste successfully obtained its first Global Fund grant for a three-year programme for malaria control. The grant aimed to reduce malaria-related morbidity and mortality by 30 % by the end of the implementation. Methods A mixed-methods approach was used to assess the impact of the grant implementation. Fifty-eight in-depth interviews, eight group interviews, 16 focus group discussions, and on-site observations were used. Morbidity data reported to the Ministry of Health were also examined to assess trends. Results The National Malaria Programme with funding support from the Global Fund grant and other development partners contributed considerably to strengthening malaria control and the general health system. It also brought direct and indirect benefits to pregnant women and to the community at large. However, it failed to achieve the stated objective of reducing malaria morbidity and mortality by 30 %. The implementation was hampered by inadequate human resources, the rigidity of Global Fund rules, weak project management and coordination, and inadequate support from external stakeholders. Conclusion Despite limitations, the grant was implemented until the agreed closing date. Considerable contributions to malaria control, health system, and the community have been made and the malaria programme was sustained. PMID:22823965

  17. Did the first Global Fund grant (2003–2006 contribute to malaria control and health system strengthening in Timor-Leste?

    Directory of Open Access Journals (Sweden)

    Martins João

    2012-07-01

    Full Text Available Abstract Background In 2003, Timor-Leste successfully obtained its first Global Fund grant for a three-year programme for malaria control. The grant aimed to reduce malaria-related morbidity and mortality by 30 % by the end of the implementation. Methods A mixed-methods approach was used to assess the impact of the grant implementation. Fifty-eight in-depth interviews, eight group interviews, 16 focus group discussions, and on-site observations were used. Morbidity data reported to the Ministry of Health were also examined to assess trends. Results The National Malaria Programme with funding support from the Global Fund grant and other development partners contributed considerably to strengthening malaria control and the general health system. It also brought direct and indirect benefits to pregnant women and to the community at large. However, it failed to achieve the stated objective of reducing malaria morbidity and mortality by 30 %. The implementation was hampered by inadequate human resources, the rigidity of Global Fund rules, weak project management and coordination, and inadequate support from external stakeholders. Conclusion Despite limitations, the grant was implemented until the agreed closing date. Considerable contributions to malaria control, health system, and the community have been made and the malaria programme was sustained.

  18. In situ conversion process systems utilizing wellbores in at least two regions of a formation

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J [Bellaire, TX; Hsu, Chia-Fu [Granada Hills, CA

    2011-09-27

    A system for heating a subsurface formation is described. The system includes a plurality of elongated heaters located in a plurality of openings in the formation. At least two of the heaters are substantially parallel to each other for at least a portion of the lengths of the heaters. At least two of the heaters have first end portions in a first region of the formation and second end portions in a second region of the formation. A source of time-varying current is configured to apply time-varying current to at least two of the heaters. The first end portions of at least two heaters are configured to have substantially the same voltage applied to them. The second portions of at least two heaters are configured to have substantially the same voltage applied to them.

  19. Droop Control with Improved Disturbance Adaption for PV System with Two Power Conversion Stages

    DEFF Research Database (Denmark)

    Liu, Hongpeng; Loh, Poh Chiang; Wang, Xiongfei

    2016-01-01

    with no or insufficient storage for cushioning climatic changes. In addition, most droop-controlled literatures have assumed a single dc-ac inverter with its input dc source fixed. Front-end dc-dc converter added to a two-stage photovoltaic (PV) system has therefore usually been ignored. To address these unresolved...... issues, an improved droop scheme for a two-stage PV system has been developed in the paper. The developed scheme uses the same control structure in both grid-connected and islanded modes, which together with properly tuned synchronizers, allows mode transfer to be seamlessly triggered. Moreover......, the proposed scheme adapts well with internal PV and external grid fluctuations, and is hence more precise with its tracking, as compared with the traditional droop scheme. Simulation and experimental results have verified these expectations, and hence the effectiveness of the proposed scheme....

  20. Combined hydrothermal liquefaction and catalytic hydrothermal gasification system and process for conversion of biomass feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.; Neuenschwander, Gary G.; Hart, Todd R.

    2017-09-12

    A combined hydrothermal liquefaction (HTL) and catalytic hydrothermal gasification (CHG) system and process are described that convert various biomass-containing sources into separable bio-oils and aqueous effluents that contain residual organics. Bio-oils may be converted to useful bio-based fuels and other chemical feedstocks. Residual organics in HTL aqueous effluents may be gasified and converted into medium-BTU product gases and directly used for process heating or to provide energy.

  1. Conversion of the NOLAPS (Navy Operational Local Atmospheric Prediction System) Model to the HP9845.

    Science.gov (United States)

    1986-02-01

    Kolmogoroff (1942), Prandt and Wieghardt (1945), Rotta (1951), and others), Mellcr and Yarmda (1974) of the Geophysical Fluid Dynamics Program at...they are not written to the history tape to save space . This capability would require code charges to the existing software. b) In the plot of the...S.D., and W.T. Thorrpson, 1982: QCerational evaluation of a turbulence closure model forecast system. Mon. Wea. Rev., 110, 1535 -1543. 2. Kolmogoroff

  2. Conversion of cold beverage dispenser's refrigeration system to R744 refrigerant

    OpenAIRE

    Visek, Matej; Elbel, Stefan; Hrnjak, Pega

    2016-01-01

    Cold beverage dispensers belong to the group of light commercial refrigeration machines that includes beverage coolers, ice machines and storage units for food items. Beverage dispensers use a vapor compression system to charge a thermal storage, usually an ice bank, which is used to indirectly cool tap water and beverage concentrate. For these machines, R290 (propane) and R744 (carbon dioxide) are among the favorite candidates to completely replace high GWP HFC refrigerants in the future. Be...

  3. Combined Production and Conversion of Energy in an Urban Integrated System

    Directory of Open Access Journals (Sweden)

    Davide Borelli

    2016-10-01

    Full Text Available Within the framework of the European Combined Efficient Large Scale Integrated Urban Systems (CELSIUS project, the Genoa demonstrator involves the insertion of a turbo expander (TE to substitute the standard throttling process in a natural gas expansion station. In this way, the currently wasted mechanical energy will be recovered, while an internal combustion combined heat and power (CHP unit will be used to meet the heating requirements of the gas before the expansion and to serve a small district heating network (DHN. Both TE and CHP are capable of delivering electric power (EP up to 1 MW. In order to match the EP production vs demand is highly desirable to use the EP extra capacity for local EP final users, such as a nearby public school and a gas refueling station (RS. For limiting the school’s consumption of fossil fuel, it is possible to use the EP surplus generated by the demonstrator to feed a heat pump in parallel to the heating conventional system. With regard to the RS, the compressors are currently driven by electric motors, with a high-energy consumption. The integrated system gives the possibility of exploiting the surplus of electricity production and of recovering heat, which would be otherwise wasted, from the intercooling of compressed gas, thus powering the DHN through a preheating system. The result expected from this strategy is a relevant energy and emissions saving due to an integrated use of the electricity generated by the Genoese demonstrator for feeding the nearby school and RS.

  4. Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems

    OpenAIRE

    Ho, Tony

    2012-01-01

    The Organic Flash Cycle (OFC) is proposed as a vapor power cycle that could potentially increase power generation and improve the utilization efficiency of renewable energy and waste heat recovery systems. A brief review of current advanced vapor power cycles including the Organic Rankine Cycle (ORC), the zeotropic Rankine cycle, the Kalina cycle, the transcritical cycle, and the trilateral flash cycle is presented. The premise and motivation for the OFC concept is that essentially by impro...

  5. Experimental Study of a Small Scale Hydraulic System for Mechanical Wind Energy Conversion into Heat

    Directory of Open Access Journals (Sweden)

    Tadas Zdankus

    2016-07-01

    Full Text Available Significant potential for reducing thermal energy consumption in buildings of moderate and cold climate countries lies within wind energy utilisation. Unlike solar irradiation, character of wind speeds in Central and Northern Europe correspond to the actual thermal energy demand in buildings. However, mechanical wind energy undergoes transformation into electrical energy before being actually used as thermal energy in most wind energy applications. The study presented in this paper deals with hydraulic systems, designed for small-scale applications to eliminate the intermediate energy transformation as it converts mechanical wind energy into heat directly. The prototype unit containing a pump, flow control valve, oil tank and piping was developed and tested under laboratory conditions. Results of the experiments showed that the prototype system is highly efficient and adjustable to a broad wind velocity range by modifying the definite hydraulic system resistance. Development of such small-scale replicable units has the potential to promote “bottom-up” solutions for the transition to a zero carbon society.

  6. A comparison of producer gas, biochar, and activated carbon from two distributed scale thermochemical conversion systems used to process forest biomass

    Science.gov (United States)

    Nathaniel Anderson; J. Greg Jones; Deborah Page-Dumroese; Daniel McCollum; Stephen Baker; Daniel Loeffler; Woodam Chung

    2013-01-01

    Thermochemical biomass conversion systems have the potential to produce heat, power, fuels and other products from forest biomass at distributed scales that meet the needs of some forest industry facilities. However, many of these systems have not been deployed in this sector and the products they produce from forest biomass have not been adequately described or...

  7. Systems Description; Sperry Low Temperature Geothermal Conversion System - Phase I and Phase II; Final Report, Volume III

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, Hugh B.

    1982-01-01

    This Volume should be considered the introductory volume to the series of six volumes even though numbered out of sequence. Volumes I and II were completed first and released in 1981 while a staff member was available to do the work. Volumes III through VI are being written and released some two years later as DOE funding became available for the purpose. They are as complete as possible considering that almost all the people involved in the program are now unavailable. This Volume III is an overview of the entire program, and many of the items presented herein briefly will be found in expanded form in one of the other five volumes. It will be noticed that assumptions and parameters such as well flow, well temperature, wet bulb temperatures, etc., involved in the several different performance calculations in the volume vary somewhat. These calculations were made at different times for different purposes and no attempt has been made to bring them into exact agreement.

  8. PVUSA experience with power conversion for grid-connected photovoltaic systems

    Energy Technology Data Exchange (ETDEWEB)

    Stolte, W.

    1995-11-01

    The Photovoltaics for Utility Scale Application (PVUSA) project was established to demonstrate photovoltaic (PV) systems in grid-connected utility applications. One of PVUSA`s key objectives is to evaluate the performance, reliability, and cost of the PV balance of system (BOS). Power conditioning units (PCUs) are the interface between the dc PV arrays and the ac utility lines, and have proved to be the most critical element in grid-connected PV systems. There are five different models of PCUs at PVUSA`s Davis and Kerman sites. This report describes the design, testing, performance characteristics, and maintenance history of each of these PCUs. PVUSA required PCUs in the power range 25 kW to 500 kW which could operate automatically and reliably under changing conditions of sunlight and changing conditions on the utility grid. Although a number of manufacturers can provide PCUs in this power range, none of these PCUs have been produced in sufficient quantity to allow refinement of a particular model into the highly reliable unit needed for long-term, unattended operation. Factory tests were useful but limited by the inability to test under full power and changing power conditions. The inability to completely test PCUs at the factory resulted in difficulty during startup, field testing, and subsequent operation. PVUSA has made significant progress in understanding the requirements for PCUs in grid-connected PV applications and improving field performance. This record of PVUSA`s experience with a variety of PCUs is intended to help utilities and their suppliers identify and retain the good performance characteristics of PCUs, and to make improvements where necessary to meet the needs of utilities.

  9. Ocean thermal energy conversion (OTEC) platform configuration and integration. Final report. Volume I. Systems requirements and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-06-01

    Studies leading to the development of two 400 MW Offshore Thermal Energy Conversion Commercial Plants are presented. This volume includes a summary of three tasks: task IIA--systems evaluation and requirements; task IIB--evaluation plan; task III--technology review; and task IV--systems integration evaluation. Task IIA includes the definition of top level requirements and an assessment of factors critical to the selection of hull configuration and size, quantification of payload requirements and characteristics, and sensitivity of system characteristics to site selection. Task IIB includes development of a methodology for systematically evaluating the candidate hullforms, based on interrelationships and priorities developed during task IIA. Task III includes the assessment of current technology and identification of deficiencies in relation to OTEC requirements and the development of plans to correct such deficiencies. Task IV involves the formal evaluation of the six candidate hullforms in relation to sit and plant capacity to quantify cost/size/capability relationships, leading to selection of an optimum commercial plant. (WHK)

  10. On the rejection of internal and external disturbances in a wind energy conversion system with direct-driven PMSG.

    Science.gov (United States)

    Li, Shengquan; Zhang, Kezhao; Li, Juan; Liu, Chao

    2016-03-01

    This paper deals with the critical issue in a wind energy conversion system (WECS) based on a direct-driven permanent magnet synchronous generator (PMSG): the rejection of lumped disturbance, including the system uncertainties in the internal dynamics and unknown external forces. To simultaneously track the motor speed in real time and capture the maximum power, a maximum power point tracking strategy is proposed based on active disturbance rejection control (ADRC) theory. In real application, system inertia, drive torque and some other parameters change in a wide range with the variations of disturbances and wind speeds, which substantially degrade the performance of WECS. The ADRC design must incorporate the available model information into an extended state observer (ESO) to compensate the lumped disturbance efficiently. Based on this principle, a model-compensation ADRC is proposed in this paper. Simulation study is conducted to evaluate the performance of the proposed control strategy. It is shown that the effect of lumped disturbance is compensated in a more effective way compared with the traditional ADRC approach. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Off-axis holographic lens spectrum-splitting photovoltaic system for direct and diffuse solar energy conversion.

    Science.gov (United States)

    Vorndran, Shelby D; Chrysler, Benjamin; Wheelwright, Brian; Angel, Roger; Holman, Zachary; Kostuk, Raymond

    2016-09-20

    This paper describes a high-efficiency, spectrum-splitting photovoltaic module that uses an off-axis volume holographic lens to focus and disperse incident solar illumination to a rectangular shaped high-bandgap indium gallium phosphide cell surrounded by strips of silicon cells. The holographic lens design allows efficient collection of both direct and diffuse illumination to maximize energy yield. We modeled the volume diffraction characteristics using rigorous coupled-wave analysis, and simulated system performance using nonsequential ray tracing and PV cell data from the literature. Under AM 1.5 illumination conditions the simulated module obtained a 30.6% conversion efficiency. This efficiency is a 19.7% relative improvement compared to the more efficient cell in the system (silicon). The module was also simulated under a typical meteorological year of direct and diffuse irradiance in Tucson, Arizona, and Seattle, Washington. Compared to a flat panel silicon module, the holographic spectrum splitting module obtained a relative improvement in energy yield of 17.1% in Tucson and 14.0% in Seattle. An experimental proof-of-concept volume holographic lens was also fabricated in dichromated gelatin to verify the main characteristics of the system. The lens obtained an average first-order diffraction efficiency of 85.4% across the aperture at 532 nm.

  12. Overview of condition monitoring and operation control of electric power conversion systems in direct-drive wind turbines under faults

    Science.gov (United States)

    Huang, Shoudao; Wu, Xuan; Liu, Xiao; Gao, Jian; He, Yunze

    2017-09-01

    Electric power conversion system (EPCS), which consists of a generator and power converter, is one of the most important subsystems in a direct-drive wind turbine (DD-WT). However, this component accounts for the most failures (approximately 60% of the total number) in the entire DD-WT system according to statistical data. To improve the reliability of EPCSs and reduce the operation and maintenance cost of DD-WTs, numerous researchers have studied condition monitoring (CM) and fault diagnostics (FD). Numerous CM and FD techniques, which have respective advantages and disadvantages, have emerged. This paper provides an overview of the CM, FD, and operation control of EPCSs in DD-WTs under faults. After introducing the functional principle and structure of EPCS, this survey discusses the common failures in wind generators and power converters; briefly reviewed CM and FD methods and operation control of these generators and power converters under faults; and discussed the grid voltage faults related to EPCSs in DD-WTs. These theories and their related technical concepts are systematically discussed. Finally, predicted development trends are presented. The paper provides a valuable reference for developing service quality evaluation methods and fault operation control systems to achieve high-performance and high-intelligence DD-WTs.

  13. Energy conversion system involving change in the density of an upwardly moving liquid

    Science.gov (United States)

    Petrick, Michael

    1989-01-01

    A system for converting thermal energy into electrical energy includes a fluid reservoir, a relatively high boiling point fluid such as lead or a lead alloy within the reservoir, a downcomer defining a vertical fluid flow path communicating at its upper end with the reservoir and an upcomer defining a further vertical fluid flow path communicating at its upper end with the reservoir. A variable area nozzle of rectangular section may terminate the upper end of the upcomer and the lower end of the of the downcomer communicates with the lower end of the upcomer. A mixing chamber is located at the lower end portion of the upcomer and receives a second relatively low boiling point fluid such as air, the mixing chamber serving to introduce the low boiling point fluid into the upcomer so as to produce bubbles causing the resultant two-phase fluid to move at high velocity up the upcomer. Means are provided for introducing heat into the system preferably between the lower end of the downcomer and the lower end of the upcomer. Power generating means are associated with the one of the vertical fluid flow paths one such power generating means being a magneto hydrodynamic electrical generator.

  14. A Two-Stage Continuous Fermentation System for Conversion of Syngas into Ethanol

    Directory of Open Access Journals (Sweden)

    Hanno Richter

    2013-08-01

    Full Text Available We have established a two-stage continuous fermentation process for production of ethanol from synthesis gas (syngas with Clostridium ljungdahlii. The system consists of a 1-L continuously stirred tank reactor as a growth stage and a 4-L bubble column equipped with a cell recycle module as an ethanol production stage. Operating conditions in both stages were optimized for the respective purpose (growth in stage one and alcohol formation in stage two. The system was fed with an artificial syngas mixture, mimicking the composition of syngas derived from lignocellulosic biomass (60% CO, 35% H2, and 5% CO2. Gas recycling was used to increase the contact area and retention time of gas in the liquid phase, improving mass transfer and metabolic rates. In stage two, the biocatalyst was maintained at high cell densities of up to 10 g DW/L. Ethanol was continuously produced at concentrations of up to 450 mM (2.1% and ethanol production rates of up to 0.37 g/(L·h. Foam control was essential to maintain reactor stability. A stoichiometric evaluation of the optimized process revealed that the recovery of carbon and hydrogen from the provided carbon monoxide and hydrogen in the produced ethanol was 28% and 74%, respectively.

  15. Cascaded Thermoelectric Conversion-Advanced Radioisotope Power Systems (CTC-ARPSs)

    Science.gov (United States)

    El-Genk, Mohamed S.; Saber, Hamed H.

    2004-02-01

    Conceptual designs of Advanced Radioisotope Power System (ARPS) with Cascaded Thermoelectric Converters (CTCs) are developed and optimized for maximum efficiency operation for End-Of Mission (EOM) electrical power of at least 100 We. These power systems each employs four General Purpose Heat Source (GPHS) bricks generating 1000 Wth at Beginning-of-Life (BOL) and 32 Cascaded Thermoelectric Modules (CTMs). Each CTM consists of a top and a bottom array of thermoelectric unicouples, which are thermally, but not electrically, coupled. The top and bottom arrays of the CTMs are connected electrically in series in two parallel strings with the same nominal voltage of > 28 VDC. The SiGe unicouples in the top array of the CTMs are optimized for nominal hot shoe temperature of 1273 K and constant cold shoe temperature of either 780 K or 980 K, depending on the thermoelectric materials of the unicouples in the bottom array. For a SiGe cold junction temperature of 780 K, the unicouples in the bottom array have p-legs of TAGS-85 and n-legs of 2N-PbTe and operate at constant hot junction temperature of 765 K and nominal cold junction temperature of 476.4 K. When the SiGe cold junction temperature is 980 K, the unicouples in the bottom arrays of CTMs have p-legs of CeFe3.5Co0.5Sb12 or CeFe3.5Co0.5Sb12 and Zn4Sb3, segments and n-legs of CoSb3 and operate at constant hot junction temperature of 965 K and nominal cold junction temperatures of 446.5 K or 493.5 K, respectively. The CTC-ARPSs have a nominal efficiency of 10.82% - 10.85% and generate BOL power of 108 We. This system efficiency is ~ 80% higher than that of State-of-the-Art (SOA) Radioisotope Thermoelectric Generators (RTGs), requiring 7 GHPS bricks and generating 105 We at BOL. The CTC-ARPSs have specific powers of 8.2 We/kg to 8.8 We/kg, which are 71% to 83% higher, respectively, than that of the SOA-RTGs, and use ~ 43% less 238PuO2 fuel.

  16. A control strategy for a variable-speed wind energy conversion system

    Science.gov (United States)

    Jacob, A.; Rajagopalan, V.; Veillette, D.

    1980-01-01

    In this article, a method of calculating an optimal control strategy for a variable-speed wind power generation scheme incorporating a squirrel cage induction machine and operating in a self-excited induction generator mode is discussed. This scheme also uses a conventional three-phase thyristor rectifier, a line-commutated inverter and an economical auxiliary commutated-voltage-source inverter. The three regulated variables are: (1) drive speed as a function of available mechanical energy by manipulating the resistive torque developed by induction generator; (2) induction motor power consumption during start-up of the wind machine of vertical axis type; (3) operating slip of the induction machine, thereby limiting start-up and braking currents. The developed strategy is also suitable for any other variable-speed drive system incorporating an induction machine.

  17. Fuel processor for fuel cell power system. [Conversion of methanol into hydrogen

    Science.gov (United States)

    Vanderborgh, N.E.; Springer, T.E.; Huff, J.R.

    1986-01-28

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  18. Index of manufacturers, researchers, and distributors currently involved in the development of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-02-01

    This index or manufacturers, distributors, researchers and others was prepared by the American Wind Energy Association (AWEA) under contract to Rockwell International Corporation. Rockwell International, in turn, is contracted with the Department of Energy to provide management and technical support for the development of wind systems for farm and rural use. The index is organized into two sections. The first section lists only names of individuals and organizations by category of interest: Manufacturer, distributor, researcher or other. Where a respondent listed more than one category that respondent's name appears under each. The second section is a compilation of all information supplied by respondents to the questionnaire. Entries are in alphabetical order by organization or individual name.

  19. Effect of increased dwell times for solvent evaporation on the bond strength and degree of conversion of an ethanol-based adhesive system.

    Science.gov (United States)

    Argolo, Saryta; Oliveira, Denise C; Fontes, Céres M; Lima, Adriano F; de Freitas, Anderson P; Cavalcanti, Andrea N

    2012-01-01

    This study evaluated the influence of the prolonged setting time of an ethanol-based adhesive system on the dentin bond strength and degree of conversion. Labial and lingual surfaces of fifteen human third molars were flattened until the dentin was exposed and randomly allocated to 3 groups (n = 10), according to the dwell time between the application of two consecutive layers of the adhesive system (Adper Single Bond Plus, 3M ESPE) and light activation: G1--control (no extra dwell time); G2 and G3--dwell time of 30 seconds and 60 seconds, respectively. After light curing, two cylinders (1.4 x 1 mm) of composite resin (Filtek Flow, 3M ESPE) were bonded to each surface and submitted to micro-shear testing, 24 hours after light curing. A similar adhesive procedure was used for the degree of conversion evaluation using Fourier transform infrared spectroscopy (FTIR). Significant differences between bond strength values (p = 0.0003) and degrees of conversion (p = 0.0004) were detected. The bond strength of G3 (60-second dwell time) was statistically higher than that of other groups. G1 (control) and G2 (30-second dwell time) presented similar results. Values of degree of conversion indicated that both the 30-second and 60-second dwell times resulted in similar and greater percentages of conversion. The use of a longer dwell time (60 seconds) might provide better solvent volatilization and monomer infiltration; bringing benefits to dentin bonding using simplified etch & rinse adhesive systems.

  20. Conversion-Integration of MSFC Nonlinear Signal Diagnostic Analysis Algorithms for Realtime Execution of MSFC's MPP Prototype System

    Science.gov (United States)

    Jong, Jen-Yi

    1996-01-01

    NASA's advanced propulsion system Small Scale Magnetic Disturbances/Advanced Technology Development (SSME/ATD) has been undergoing extensive flight certification and developmental testing, which involves large numbers of health monitoring measurements. To enhance engine safety and reliability, detailed analysis and evaluation of the measurement signals are mandatory to assess its dynamic characteristics and operational condition. Efficient and reliable signal detection techniques will reduce the risk of catastrophic system failures and expedite the evaluation of both flight and ground test data, and thereby reduce launch turn-around time. During the development of SSME, ASRI participated in the research and development of several advanced non- linear signal diagnostic methods for health monitoring and failure prediction in turbomachinery components. However, due to the intensive computational requirement associated with such advanced analysis tasks, current SSME dynamic data analysis and diagnostic evaluation is performed off-line following flight or ground test with a typical diagnostic turnaround time of one to two days. The objective of MSFC's MPP Prototype System is to eliminate such 'diagnostic lag time' by achieving signal processing and analysis in real-time. Such an on-line diagnostic system can provide sufficient lead time to initiate corrective action and also to enable efficient scheduling of inspection, maintenance and repair activities. The major objective of this project was to convert and implement a number of advanced nonlinear diagnostic DSP algorithms in a format consistent with that required for integration into the Vanderbilt Multigraph Architecture (MGA) Model Based Programming environment. This effort will allow the real-time execution of these algorithms using the MSFC MPP Prototype System. ASRI has completed the software conversion and integration of a sequence of nonlinear signal analysis techniques specified in the SOW for real

  1. Kinetic modeling of a bi-enzymatic system for efficient conversion of lactose to lactobionic acid.

    Science.gov (United States)

    Van Hecke, Wouter; Bhagwat, Aditya; Ludwig, Roland; Dewulf, Jo; Haltrich, Dietmar; Van Langenhove, Herman

    2009-04-01

    A model has been developed to describe the interaction between two enzymes and an intermediary redox mediator. In this bi-enzymatic process, the enzyme cellobiose dehydrogenase oxidizes lactose at the C-1 position of the reducing sugar moiety to lactobionolactone, which spontaneously hydrolyzes to lactobionic acid. 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt is used as electron acceptor and is continuously regenerated by laccase. Oxygen is the terminal electron acceptor and is fully reduced to water by laccase, a copper-containing oxidase. Oxygen is added to the system by means of bubble-free oxygenation. Using the model, the productivity of the process is investigated by simultaneous solution of the rate equations for varying enzyme quantities and redox mediator concentrations, solved with the aid of a numerical solution. The isocharts developed in this work provide an easy-to-use graphical tool to determine optimal process conditions. The model allows the optimization of the employed activities of the two enzymes and the redox mediator concentration for a given overall oxygen mass transfer coefficient by using the isocharts. Model predictions are well in agreement with the experimental data.

  2. Technology of VAr Compensators for Induction Generator Applications in Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    A. F. Zobaa

    2006-09-01

    Full Text Available Many of today utility interconnected wind farms use induction generator (IG to convert the captured wind mechanical power into electricity. Induction generator has some advantages over the synchronous generator (SG. The main advantages are its robustness and its capability to be synchronized directly to the grid. The main disadvantage, however, is its dependency on the grid for supplying its own reactive power ‘VAr’. Whether fixed or adjustable VAr systems are connected across its terminal, IG must operate at unity power factor at the rated loading while the wind power varies. With supervised control and appropriate coordination, VAr can be used to the benefits of both the wind farm developer and the hosting utility. The incorporation of today adjustable reactive power compensators such as the Static VAr Compensation (SVC and Static Synchronous Compensator (STATCOM with IG are vital ingredient toward a successful penetration of wind energy in today distribution grid to ensure voltage stability during the steady state and transient periods.

  3. A Direct Conversion Receiver Adopting Balanced Three-Phase Analog System

    Science.gov (United States)

    Yamaji, Takafumi; Ueno, Takeshi; Itakura, Tetsuro

    Recent advanced technology makes digital circuits small and the number of digital functional blocks that can be integrated on a single chip is increasing rapidly. On the other hand, reduction in the size of analog circuits has been insufficient. This means that the analog circuit area is relatively large, and reducing analog circuit area can be effective to make a low cost radio receiver. In this paper, a new wireless receiver architecture that occupies small analog area is proposed, and measured results of the core analog blocks are described. To reduce the analog area, a balanced 3-phase analog system is adopted and the functions of analog baseband filters and VGAs are moved to the digital domain. The test chip consists of a 3-phase downconverter and a 3-phase ADC. There is no analog baseband filter on the chip and the analog filter is assumed to be replaced with a digital filter. The downconverter and ADC occupy 0.28mm2. The measured results show the possibility that the requirements for IMT-2000 are fulfilled even with a small chip area.

  4. Systemic Oxidative Stress and Conversion to Dementia of Elderly Patients with Mild Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Carlo Cervellati

    2014-01-01

    Full Text Available Mild cognitive impairment (MCI is regarded as a prodromal phase of late onset Alzheimer’s disease (LOAD. It has been proposed that oxidative stress (OxS might be implicated in the pathogenesis of LOAD. The aim of this study was to investigate whether a redox imbalance measured as serum level of hydroperoxides (i.e., by-products of lipid peroxidation and/or serum antioxidant capacity might be predictive of the clinical progression of MCI to LOAD. The levels of these two markers were measured in 111 patients with MCI (follow-up: 2.0 ± 0.6 years, 105 patients with LOAD, and 118 nondemented healthy controls. Multivariate analysis adjusted for potential confounding factors, including age, gender, smoking, and comorbidities, showed a significant increase (P<0.05 in baseline levels of OxS in MCI and LOAD as compared to cognitive healthy controls. No differences in either of OxS markers were found by comparing MCI patients who converted (n = 29 or not converted (n = 82 to LOAD. Overall, these results suggest that systemic OxS might be a precocious feature of MCI and LOAD. However, the role of OxS as an early prognostic marker of progression to LOAD needs further investigations.

  5. Utilization of non-conventional systems for conversion of biomass to food components

    Science.gov (United States)

    Karel, M.; Nakhost, Z.

    1989-01-01

    Described here is work accomplished in investigating the potential use of micro-algae in yielding useful macronutrients for closed ecological life support systems in space habitats. Analysis of the chemical composition of the blue-green alga Synechoccus 6311 was done in the present work, and was compared to values found in previous work on the green algae Scenedesmus obliquus. Similar values were obtained for proteins, and lower values for nucleic acids and lipids. A second part of the work involved fabrication of food products containing various levels of incorporated algae (S. obliquus) proteins and/or lipids. Protein isolate was incorporated into a variety of food products such as bran muffins, fettuccine (spinach noodle imitation), and chocolate chip cookies. In the sensory analysis, the greenish color of the bran muffins and cookies was not found to be objectionable. The mild spinachy flavor was less detectable in chocolate chip cookies than in bran muffins. The color and taste of the algae noodles were found to be pleasant and compared well with commercially available spinach noodles.

  6. Investigation of heat exchangers for energy conversion systems of megawatt-class space power plants

    Science.gov (United States)

    Ilmov, D. N.; Mamontov, Yu. N.; Skorohodov, A. S.; Smolyarov, V. A.; Filatov, N. I.

    2016-01-01

    The specifics of operation (high temperatures in excess of 1000 K and large pressure drops of several megapascals between "hot" and "cold" coolant paths) of heat exchangers in the closed circuit of a gasturbine power converter operating in accordance with the Brayton cycle with internal heat recovery are analyzed in the context of construction of space propulsion systems. The design of a heat-exchange matrix made from doubly convex stamped plates with a specific surface relief is proposed. This design offers the opportunity to construct heat exchangers with the required parameters (strength, rigidity, weight, and dimensions) for the given operating conditions. The diagram of the working area of a test bench is presented, and the experimental techniques are outlined. The results of experimental studies of heat exchange and flow regimes in the models of heat exchangers with matrices containing 50 and 300 plates for two pairs of coolants (gas-gas and gas-liquid) are detailed. A criterion equation for the Nusselt number in the range of Reynolds numbers from 200 to 20 000 is proposed. The coefficients of hydraulic resistance for each coolant path are determined as functions of the Reynolds number. It is noted that the pressure in the water path in the "gas-liquid" series of experiments remained almost constant. This suggests that no well-developed processes of vaporization occurred within this heat-exchange matrix design even when the temperature drop between gas and water was as large as tens or hundreds of degrees. The obtained results allow one to design flight heat exchangers for various space power plants.

  7. Conversion of native terrestrial ecosystems in Hawai‘i to novel grazing systems: a review

    Science.gov (United States)

    Leopold, Christina R.; Hess, Steven C.

    2017-01-01

    The remote oceanic islands of Hawai‘i exemplify the transformative effects that non-native herbivorous mammals can bring to isolated terrestrial ecosystems. We reviewed published literature containing systematically collected, analyzed, and peer-reviewed original data specifically addressing direct effects of non-native hoofed mammals (ungulates) on terrestrial ecosystems, and indirect effects and interactions on ecosystem processes in Hawai‘i. The effects of ungulates on native vegetation and ecosystems were addressed in 58 original studies and mostly showed strong short-term regeneration of dominant native trees and understory ferns after ungulate removal, but unassisted recovery was dependent on the extent of previous degradation. Ungulates were associated with herbivory, bark-stripping, disturbance by hoof action, soil erosion, enhanced nutrient cycling from the interaction of herbivory and grasses, and increased pyrogenicity and competition between native plants and pasture grasses. No studies demonstrated that ungulates benefitted native ecosystems except in short-term fire-risk reduction. However, non-native plants became problematic and continued to proliferate after release from herbivory, including at least 11 species of non-native pasture grasses that had become established prior to ungulate removal. Competition from non-native grasses inhibited native species regeneration where degradation was extensive. These processes have created novel grazing systems which, in some cases, have irreversibly altered Hawaii’s terrestrial ecology. Non-native plant control and outplanting of rarer native species will be necessary for recovery where degradation has been extensive. Lack of unassisted recovery in some locations should not be construed as a reason to not attempt restoration of other ecosystems.

  8. Stochastic Model Predictive Fault Tolerant Control Based on Conditional Value at Risk for Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Yun-Tao Shi

    2018-01-01

    Full Text Available Wind energy has been drawing considerable attention in recent years. However, due to the random nature of wind and high failure rate of wind energy conversion systems (WECSs, how to implement fault-tolerant WECS control is becoming a significant issue. This paper addresses the fault-tolerant control problem of a WECS with a probable actuator fault. A new stochastic model predictive control (SMPC fault-tolerant controller with the Conditional Value at Risk (CVaR objective function is proposed in this paper. First, the Markov jump linear model is used to describe the WECS dynamics, which are affected by many stochastic factors, like the wind. The Markov jump linear model can precisely model the random WECS properties. Second, the scenario-based SMPC is used as the controller to address the control problem of the WECS. With this controller, all the possible realizations of the disturbance in prediction horizon are enumerated by scenario trees so that an uncertain SMPC problem can be transformed into a deterministic model predictive control (MPC problem. Finally, the CVaR object function is adopted to improve the fault-tolerant control performance of the SMPC controller. CVaR can provide a balance between the performance and random failure risks of the system. The Min-Max performance index is introduced to compare the fault-tolerant control performance with the proposed controller. The comparison results show that the proposed method has better fault-tolerant control performance.

  9. A Two-Level Sensorless MPPT Strategy Using SRF-PLL on a PMSG Wind Energy Conversion System

    Directory of Open Access Journals (Sweden)

    Amina Echchaachouai

    2017-01-01

    Full Text Available In this paper, a two-level sensorless Maximum Power Point Tracking (MPPT strategy is presented for a variable speed Wind Energy Conversion System (WECS. The proposed system is composed of a wind turbine, a direct-drive Permanent Magnet Synchronous Generator (PMSG and a three phase controlled rectifier connected to a DC load. The realised generator output power maximization analysis justifies the use of the Field Oriented Control (FOC giving the six Pulse Width Modulation (PWM signals to the active rectifier. The generator rotor speed and position required by the FOC and the sensorless MPPT are estimated using a Synchronous Reference Frame Phase Locked Loop (SRF-PLL. The MPPT strategy used consists of two levels, the first level is a power regulation loop and the second level is an extremum seeking bloc generating the coefficient gathering the turbine characteristics. Experimental results validated on a hardware test setup using a DSP digital board (dSPACE 1104 are presented. Figures illustrating the estimated speed and angle confirm that the SRF-PLL is able to give an estimated speed and angle which closely follow the real ones. Also, the power at the DC load and the power at the generator output indicate that the MPPT gives optimum extracted power. Finally, other results show the effectiveness of the adopted approach in real time applications.

  10. Image quality evaluation of direct-conversion digital mammography system with new dual a-Se layer detector

    Science.gov (United States)

    Kuwabara, Takao; Iwasaki, Nobuyuki; Sendai, Tomonari; Furue, Ryosuke; Agano, Toshitaka

    2009-02-01

    To increase the detection performance of breast cancers in mammograms, we need to improve shape delineation of micro calcifications and tumors. We accomplished this by developing a direct-conversion mammography system with an optical reading method and a new dual a-Se layer detector. The system achieved both small pixel size (50 micrometer) and a high Detective Quantum Efficiency (DQE) realized by 100 % of fill factor and noise reduction. We evaluated image quality performance and determined the best exposure conditions. We measured DQE and Modulation Transfer Function(MTF) according to the IEC62220-1-2. High DQE was maintained at a low radiation dosage, indicating that the optical reading method accompanies low noises. Response of MTF was maintained at up to the Nyquist frequency of 10 cyc/mm, which corresponds to 50 micrometer pixel size. To determine the best exposure conditions, we measured Contrast to Noise Ratio (CNR) and visually evaluated images of a resected breast under conditions of MoMo, MoRh, and WRh. There were occasional disagreements between the exposure conditions for achieving the maximum CNR and those for the best image graded by the visual evaluation. This was probably because CNR measurement does not measure effects of scattered X-ray. The images verified the improvement in detection and delineation performance of micro calcifications and tumors.

  11. Comparison of Stirling engines for use with a 25-kW disk-electric conversion system

    Science.gov (United States)

    Shaltens, Richard K.

    1987-01-01

    Heat engines were evaluated for terrestrial solar heat receivers. The Stirling Engine was identified as one of the most promising engines for terrestrial applications. The potential to meet the Department of Energy (DOE) goals for performance and cost can be met by the free-piston Stirling engine. NASA Lewis is providing technical management for an Advanced Stirling Conversion System (ASCS) through a cooperative interagency agreement with DOE. Parallel contracts were awarded for conceptual designs of an ASCS. Each design will feature a free-piston Stirling engine, a liquid-metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting long-term performance and goals. The Mechanical Technology, Ins. (MTI) design incorporates a linear alternator to directly convert the solar energy to electricity while the Stirling Technology Company (STC) generates electrical power indirectly by using a hydraulic output to a ground-bases hydraulic pump/motor coupled to a rotating alternator. Both designs use technology which can reasonably be expected to be available in the 1980's. The ASCS designs using a free-piston Stirling engine, a heat transport system, a receiver, and the methods of providing electricity to the utility grid will be discussed.

  12. Test Requirements and Conceptual Design for a Potassium Test Loop to Support an Advanced Potassium Rankine Cycle Power Conversion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Yoder, JR.G.L.

    2006-03-08

    Parameters for continuing the design and specification of an experimental potassium test loop are identified in this report. Design and construction of a potassium test loop is part of the Phase II effort of the project ''Technology Development Program for an Advanced Potassium Rankine Power Conversion System''. This program is supported by the National Aeronautics and Space Administration. Design features for the potassium test loop and its instrumentation system, specific test articles, and engineered barriers for ensuring worker safety and protection of the environment are described along with safety and environmental protection requirements to be used during the design process. Information presented in the first portion of this report formed the basis to initiate the design phase of the program; however, the report is a living document that can be changed as necessary during the design process, reflecting modifications as additional design details are developed. Some portions of the report have parameters identified as ''to be determined'' (TBD), reflecting the early stage of the overall process. In cases where specific design values are presently unknown, the report attempts to document the quantities that remain to be defined in order to complete the design of the potassium test loop and supporting equipment.

  13. Drinking Water State Revolving Fund

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Drinking Water State Revolving Fund (DWSRF) National Information Management System collects information that provide a record of progress and accountability for...

  14. Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 6: Closed-cycle gas turbine systems. [energy conversion efficiency in electric power plants

    Science.gov (United States)

    Amos, D. J.; Fentress, W. K.; Stahl, W. F.

    1976-01-01

    Both recuperated and bottomed closed cycle gas turbine systems in electric power plants were studied. All systems used a pressurizing gas turbine coupled with a pressurized furnace to heat the helium for the closed cycle gas turbine. Steam and organic vapors are used as Rankine bottoming fluids. Although plant efficiencies of over 40% are calculated for some plants, the resultant cost of electricity was found to be 8.75 mills/MJ (31.5 mills/kWh). These plants do not appear practical for coal or oil fired plants.

  15. A Study of Mars Dust Environment Simulation at NASA Johnson Space Center Energy Systems Test Area Resource Conversion Test Facility

    Science.gov (United States)

    Chen, Yuan-Liang Albert

    1999-01-01

    The dust environment on Mars is planned to be simulated in a 20 foot thermal-vacuum chamber at the Johnson Space Center, Energy Systems Test Area Resource Conversion Test Facility in Houston, Texas. This vacuum chamber will be used to perform tests and study the interactions between the dust in Martian air and ISPP hardware. This project is to research, theorize, quantify, and document the Mars dust/wind environment needed for the 20 foot simulation chamber. This simulation work is to support the safety, endurance, and cost reduction of the hardware for the future missions. The Martian dust environment conditions is discussed. Two issues of Martian dust, (1) Dust Contamination related hazards, and (2) Dust Charging caused electrical hazards, are of our interest. The different methods of dust particles measurement are given. The design trade off and feasibility were studied. A glass bell jar system is used to evaluate various concepts for the Mars dust/wind environment simulation. It was observed that the external dust source injection is the best method to introduce the dust into the simulation system. The dust concentration of 30 Mg/M3 should be employed for preparing for the worst possible Martian atmosphere condition in the future. Two approaches thermal-panel shroud for the hardware conditioning are discussed. It is suggested the wind tunnel approach be used to study the dust charging characteristics then to be apply to the close-system cyclone approach. For the operation cost reduction purpose, a dehumidified ambient air could be used to replace the expensive CO2 mixture for some tests.

  16. Conversational sensing

    Science.gov (United States)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  17. Legacy2Drupal - Conversion of an existing oceanographic relational database to a semantically enabled Drupal content management system

    Science.gov (United States)

    Maffei, A. R.; Chandler, C. L.; Work, T.; Allen, J.; Groman, R. C.; Fox, P. A.

    2009-12-01

    Content Management Systems (CMSs) provide powerful features that can be of use to oceanographic (and other geo-science) data managers. However, in many instances, geo-science data management offices have previously designed customized schemas for their metadata. The WHOI Ocean Informatics initiative and the NSF funded Biological Chemical and Biological Data Management Office (BCO-DMO) have jointly sponsored a project to port an existing, relational database containing oceanographic metadata, along with an existing interface coded in Cold Fusion middleware, to a Drupal6 Content Management System. The goal was to translate all the existing database tables, input forms, website reports, and other features present in the existing system to employ Drupal CMS features. The replacement features include Drupal content types, CCK node-reference fields, themes, RDB, SPARQL, workflow, and a number of other supporting modules. Strategic use of some Drupal6 CMS features enables three separate but complementary interfaces that provide access to oceanographic research metadata via the MySQL database: 1) a Drupal6-powered front-end; 2) a standard SQL port (used to provide a Mapserver interface to the metadata and data; and 3) a SPARQL port (feeding a new faceted search capability being developed). Future plans include the creation of science ontologies, by scientist/technologist teams, that will drive semantically-enabled faceted search capabilities planned for the site. Incorporation of semantic technologies included in the future Drupal 7 core release is also anticipated. Using a public domain CMS as opposed to proprietary middleware, and taking advantage of the many features of Drupal 6 that are designed to support semantically-enabled interfaces will help prepare the BCO-DMO database for interoperability with other ecosystem databases.

  18. Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 10: Liquid-metal MHD systems. [energy conversion efficiency of electric power plants using liquid metal magnetohydrodynamics

    Science.gov (United States)

    Holman, R. R.; Lippert, T. E.

    1976-01-01

    Electric Power Plant costs and efficiencies are presented for two basic liquid-metal cycles corresponding to 922 and 1089 K (1200 and 1500 F) for a commercial applications using direct coal firing. Sixteen plant designs are considered for which major component equipment were sized and costed. The design basis for each major component is discussed. Also described is the overall systems computer model that was developed to analyze the thermodynamics of the various cycle configurations that were considered.

  19. Edmonton Obesity Staging System Prevalence and Association with Weight Loss in a Publicly Funded Referral-Based Obesity Clinic

    OpenAIRE

    Canning, Karissa L.; Brown, Ruth E.; Wharton, Sean; Sharma, Arya M.; Kuk, Jennifer L.

    2015-01-01

    Objectives. To determine the distribution of EOSS stages and differences in weight loss achieved according to EOSS stage, in patients attending a referral-based publically funded multisite weight management clinic. Subjects/Methods. 5,787 obese patients were categorized using EOSS staging using metabolic risk factors, medication use, and severity of doctor diagnosis of obesity-related physiological, functional, and psychological comorbidities from electronic patient files. Results. The preval...

  20. 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

    Science.gov (United States)

    Clark, T. B. (Editor)

    1979-01-01

    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.

  1. Degree of conversion and leached monomers of urethane dimethacrylate-hydroxypropyl methacrylate-based dental resin systems.

    Science.gov (United States)

    Zhang, Meng; Puska, Mervi A; Botelho, Michael G; Säilynoja, Eija S; Matinlinna, Jukka P

    2016-01-01

    The degree of conversion (DC) and monomer leaching of three experimental urethane dimethacrylate (UEDMA)-hydroxypropyl methacrylate (HPMA)-based resin systems were studied. Three experimental resins (E1: 70.6 wt% UEDMA + 27.4 wt% HPMA, E2: 80.6 wt% UEDMA + 17.4 wt% HPMA, E3: 90.6 wt% UEDMA + 7.4 wt% HPMA) and one control resin [C: 70.6 wt% bis-phenol A glycidyl methacrylate (bis-GMA) + 27.4 wt% methyl methacrylate (MMA)] were prepared. For the DC test, cylindrical specimens [1.5 mm (h) × 6 mm (d)] were scanned with an ATR-FTIR instrument before and after light-curing (n = 5). For the monomer leaching test, block-shaped specimens [5.67 mm (l) × 2.00 mm (w) × 2.00 mm (h)] were light-cured (n = 6), stored in a 75% ethanol:water solution for 3 days, and then analyzed with HPLC. The UEDMA-HPMA-based experimental groups showed higher DC (62-78%) than the bis-GMA-MMA-based control group (58-66%), and the DC decreased as the UEDMA content increased (P HPMA) and dimethacrylate (HPMA-based resins, therefore, exhibited higher DC and less monomer leaching compared to the bis-GMA-MMA-based resin. (J Oral Sci 58, 15-22, 2016).

  2. Verification of a 2 kWe Closed-Brayton-Cycle Power Conversion System Mechanical Dynamics Model

    Science.gov (United States)

    Ludwiczak, Damian R.; Le, Dzu K.; McNelis, Anne M.; Yu, Albert C.; Samorezov, Sergey; Hervol, Dave S.

    2005-01-01

    Vibration test data from an operating 2 kWe closed-Brayton-cycle (CBC) power conversion system (PCS) located at the NASA Glenn Research Center was used for a comparison with a dynamic disturbance model of the same unit. This effort was performed to show that a dynamic disturbance model of a CBC PCS can be developed that can accurately predict the torque and vibration disturbance fields of such class of rotating machinery. The ability to accurately predict these disturbance fields is required before such hardware can be confidently integrated onto a spacecraft mission. Accurate predictions of CBC disturbance fields will be used for spacecraft control/structure interaction analyses and for understanding the vibration disturbances affecting the scientific instrumentation onboard. This paper discusses how test cell data measurements for the 2 kWe CBC PCS were obtained, the development of a dynamic disturbance model used to predict the transient torque and steady state vibration fields of the same unit, and a comparison of the two sets of data.

  3. Self-phase modulation induced transmission penalty reduction in a 5 Gbit/s FM/AM conversion system experiment over 205 km of standard fiber

    DEFF Research Database (Denmark)

    Jørgensen, Bo Foged; Pedersen, Rune Johan Skullerud; Jørgensen, Carsten Gudmann

    1994-01-01

    The transmission penalty of a standard non-dispersion shifted fiber is experimentally demonstrated to be reduced by self-phase modulation due to the optical Kerr effect. A 2 dB reduction of transmission penalty is achieved in a 5 Gbit/s FM/AM conversion system experiment over 205 km of fiber...

  4. Beef Cattle Farms’ Conversion to the Organic System. Recommendations for Success in the Face of Future Changes in a Global Context

    Directory of Open Access Journals (Sweden)

    Alfredo J. Escribano

    2016-06-01

    Full Text Available Dehesa is a remarkable agroforestry system, which needs the implementation of sustainable production systems in order to reduce its deterioration. Moreover, its livestock farms need to adapt to a new global market context. As a response, the organic livestock sector has expanded not only globally but also in the region in search for increased overall sustainability. However, conversions to the organic system have been commonly carried out without analyzing farms’ feasibility to do so. This analysis is necessary before implementing any new production system in order to reduce both the diversity of externalities that the variety of contexts leads to and the vulnerability of the DDehesa ecosystem to small management changes. Within this context and in the face of this gap in knowledge, the present paper analyzes the ease of such conversions and the farms’ chances of success after conversion in the face of global changes (market and politics. Different aspects (“areas of action” were studied and integrated within the Global Conversion Index (GCI, and the legal requirement for European organic farming, organic principles, future challenges for ruminants’ production systems, as well as the lines of action for the post-2013 CAP (Common Agricultural Policy and their impacts on the beef cattle sector were taken into account. Results revealed that farms must introduce significant changes before initiating the conversion process, since they had very low scores on the GCI (42.74%, especially with regard to health and agro-ecosystem management (principle of Ecology. Regarding rearing and animal welfare (principle of justice/fairness, farms were close to the organic system. From the social point of view, active participation in manufacturing and marketing of products should be increased.

  5. 13 CFR 130.500 - Funding.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Funding. 130.500 Section 130.500 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS DEVELOPMENT CENTERS § 130.500 Funding. The SBA funds Cooperative Agreements through its internal Letter of Credit Replacement System...

  6. PVMaT - OMNION Series 3000: Photovoltaic Power Conversion System for Utility Interconnected Application; Annual Report, May 1997 - February 1999

    Energy Technology Data Exchange (ETDEWEB)

    Porter, D.

    2000-09-13

    This report details the work performed which was geared towards making advancements in three major areas (cost, reliability and performance) of three-phase, utility interconnected and photovoltaic power conversion.

  7. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system.

    Science.gov (United States)

    Ohtomo, Yoko; Ijiri, Akira; Ikegawa, Yojiro; Tsutsumi, Masazumi; Imachi, Hiroyuki; Uramoto, Go-Ichiro; Hoshino, Tatsuhiko; Morono, Yuki; Sakai, Sanae; Saito, Yumi; Tanikawa, Wataru; Hirose, Takehiro; Inagaki, Fumio

    2013-01-01

    Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in-situ pressure (0-100 MPa) and temperature (0-70°C) conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 ml/min, respectively) were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa) at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ(13)Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to acetate.

  8. Biological CO2 conversion to acetate in subsurface coal-sand formation using a high-pressure reactor system

    Directory of Open Access Journals (Sweden)

    Yoko eOhtomo

    2013-12-01

    Full Text Available Geological CO2 sequestration in unmineable subsurface oil/gas fields and coal formations has been proposed as a means of reducing anthropogenic greenhouse gasses in the atmosphere. However, the feasibility of injecting CO2 into subsurface depends upon a variety of geological and economic conditions, and the ecological consequences are largely unpredictable. In this study, we developed a new flow-through-type reactor system to examine potential geophysical, geochemical and microbiological impacts associated with CO2 injection by simulating in situ pressure (0–100 MPa and temperature (0–70°C conditions. Using the reactor system, anaerobic artificial fluid and CO2 (flow rate: 0.002 and 0.00001 mL/min, respectively were continuously supplemented into a column comprised of bituminous coal and sand under a pore pressure of 40 MPa (confined pressure: 41 MPa at 40°C for 56 days. 16S rRNA gene analysis of the bacterial components showed distinct spatial separation of the predominant taxa in the coal and sand over the course of the experiment. Cultivation experiments using sub-sampled fluids revealed that some microbes survived, or were metabolically active, under CO2-rich conditions. However, no methanogens were activated during the experiment, even though hydrogenotrophic and methylotrophic methanogens were obtained from conventional batch-type cultivation at 20°C. During the reactor experiment, the acetate and methanol concentration in the fluids increased while the δ13Cacetate, H2 and CO2 concentrations decreased, indicating the occurrence of homo-acetogenesis. 16S rRNA genes of homo-acetogenic spore-forming bacteria related to the genus Sporomusa were consistently detected from the sandstone after the reactor experiment. Our results suggest that the injection of CO2 into a natural coal-sand formation preferentially stimulates homo-acetogenesis rather than methanogenesis, and that this process is accompanied by biogenic CO2 conversion to

  9. Competition preparation guideline in undergraduate program of information system school of Industrial Engineering Telkom University based on knowledge conversion

    Science.gov (United States)

    Darmawan, F. R.; Soesanto, R. P.; Kurniawati, A.; Kurniawan, M. T.

    2017-12-01

    The role of higher education in the development of science and technology is not only from the contribution of the high-quality alumni but also from the research and relevant competition with the needs of development in such a country. In a competition, the student can improve their soft skill and academic skill such as analytical and critical thinking, communication skills and mental. The number of relevant competition by students is also included in accreditation clause, therefore student involvement in competition is seen as important for the undergraduate program in University. The most problem in university is the high turnover from the student. Bachelor program in Indonesia usually takes 4 years to complete, and the high turnover causes the student come and go as they are a graduate from the institution without preserving the knowledge and experience from the competition to other students. This research aims to develop a guidance for competition preparation in the university by using knowledge conversion. The object of this research is an information system undergraduate program in the school of industrial engineering Telkom University. The best practice selection is done by using factor rating method. Delphi method is used to identify the criteria, and AHP method is used to calculate the weight of each criterion. From the factor rating result it is known that from 3 respondent, best practice from respondent A (7.321) is used for preparing the programming competition in an undergraduate program of information system in the school of industrial engineering Telkom University. FGD is done to disseminate the selected best practice into the process stakeholder which is head of the student affair of the school of industrial engineering, students, and laboratory assistants. Future research can be done to create more comprehensive criteria for selecting the best practice.

  10. Roadmap on optical energy conversion

    Science.gov (United States)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-07-01

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  11. Mechanochemical Energy Conversion

    Science.gov (United States)

    Pines, E.; And Others

    1973-01-01

    Summarizes the thermodynamics of macromolecular systems, including theories and experiments of cyclic energy conversion with rubber and collagen as working substances. Indicates that an early introduction into the concept of chemical potential and solution thermodynamics is made possible through the study of the cyclic processes. (CC)

  12. Predicting AD conversion

    DEFF Research Database (Denmark)

    Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz

    2013-01-01

    To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...

  13. Interview series focuses on IDRC-funded research on climate ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    In Conversation is a series of interviews and videos of research partners working on climate change adaptation projects in Africa, Asia, and Latin America and the Caribbean, funded through IDRC's Climate Change and Water program.

  14. Danish mutual fund performance

    DEFF Research Database (Denmark)

    Christensen, Michael

    2013-01-01

    This article provides the first independent performance analysis of Danish mutual funds. We analyse selectivity and market timing abilities for 71 mutual funds that have been in operation from 2001 to 2010. The results show great fund performance diversity. Half the funds have performed neutrally...

  15. Comparative study of energy conversion system dedicated to a small wind turbine; Etude comparative de chaines de conversion d'energie dediees a une eolienne de petite puissance

    Energy Technology Data Exchange (ETDEWEB)

    Mirecki, A

    2005-07-01

    This study presents a comparison of architectures and strategies of energy management dedicated to VAWT turbines such as Savonius. A Maximum Power Point Tracking must be implemented in order to optimize the energetic behavior. A torque or a speed control, or an indirect control of the DC bus current is possible. In the fact that the wind turbine characteristic is unknown, an operational research based on fuzzy logic is proposed. Aiming to minimize the cost of the static conversion structure, simple structures (diode bridge inverter, associated with DC-DC chopper) are analyzed and compared with a system based on a PWM Voltage Source Inverter. A test bench has been realized in the meantime as a system simulation. Comparisons of the provided energy are made for different wind speeds allowing to evaluate the performance of each structure and of the control strategies. (author)

  16. National strategy for suicide prevention in Japan: impact of a national fund on progress of developing systems for suicide prevention and implementing initiatives among local authorities.

    Science.gov (United States)

    Nakanishi, Miharu; Yamauchi, Takashi; Takeshima, Tadashi

    2015-01-01

    In Japan, the Cabinet Office released the 'General Principles of Suicide Prevention Policy' in 2007 and suggested nine initiatives. In 2009, a national fund was launched to help prefectures (the administrative divisions of Japan) and local authorities implement five categories of suicide-prevention programs. This paper examines the impact of the national fund on the establishment of the systems for suicide prevention and the implementation of these initiatives among local authorities. The present study included 1385 local authorities (79.5%) from all 47 prefectures that responded to the cross-sectional questionnaire survey. Improved suicide-prevention systems and the implementation of nine initiatives in April 2013 were observed among 265 local authorities (19.1%) that implemented 'Training of community service providers' and 'Public awareness campaigns'; 178 local authorities (12.9%) that implemented 'Face-to-face counseling', 'Training of community service providers' and 'Public awareness campaigns'; and 324 local authorities (23.4%) that implemented 'Trauma-informed policies and practices'. There was no significant difference in suicide-prevention systems and the implementation of nine initiatives between 203 local authorities (14.7%) that implemented only 'Public awareness campaigns' and 231 local authorities (16.7%) that did not implement any suicide-prevention programs. The results of our study suggest that the national fund promoted the establishment of community systems for suicide prevention and helped implement initiatives among local authorities. The national suicide-prevention strategy in Japan should explore a standard package of programs to guide community suicide-prevention efforts with a sustained workforce among local authorities. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

  17. KNOWLEDGE CONVERSION PADA PROSES PERENCANAAN PROYEK DI PT. LEN RAILWAY SYSTEM UNTUK STANDARDISASI PROSES DENGAN METODE SECI

    Directory of Open Access Journals (Sweden)

    Atikah Sayyidatu Nisaa

    2013-04-01

    Full Text Available PT LEN Railway System bergerak pada pembangunan proyek pensinyalan kereta api, namun pada proses perencanaan proyek pada perusahaan tersebut masih berupa tacit knowledge (pengalaman pekerja yang akan hilang. Oleh karena itu, diperlukan adanya konversi knowledge pekerja yang masih berbentuk tacit knowledge menjadi knowledge yang terdokumentasikan ke dalam bentuk explicit knowledge. Penelitian ini menggunakan metode SECI (Socialization, Externalization, Combination, Internalization. Pada tahap socialization dilakukan eksplorasi data kepada pelaku proyek yang bersangkutan mengenai proses bisnis suatu aktivitas maupun tacit dan explicit knowledge dari masing-masing aktivitas. Pada tahap externalization dilakukan pendokumentasian dari hasil eksplorasi data. Pada tahap combination dilakukan pemilihan best practice dengan menggunakan beberapa tools yaitu: metode Delphi, metode AHP dan pemilihan best practice menggunakan metode factor rating. Best practice yang didapatkan akan dikombinasikan dengan proses aktivitas dari PMBOK. Pada tahap internalization dilakukan penginformasian kepada pekerja mengenai best practice yang telah didapatkan dari hasil penelitian. Best practice yang terpilih dari hasil perhitungan factor rating didapatkan sebagai berikut best practice pembuatan WBS adalah proses bisnis dari responden 2 dengan nilai sebesar 8,710, untuk penentuan jadwal proyek dari responden 2 dengan nilai sebesar 8,067, untuk penentuan biaya proyek dari responden 3 sebesar 9,554, untuk pemilihan supplier dari responden 1 sebesar 8,330, untuk pembuatan desain proyek dari responden 1 sebesar 8,368 dan untuk pengadaan barang dari responden 1 dengan nilai sebesar 8,195. Kata Kunci : knowledge conversion, knowledge management, metode SECI Abstract The economic foundation movement of industrial era into the knowledge era has involved the project PT LEN Railway System which operates in the construction of the railway signaling project. This research uses SECI

  18. LoMA-B: a simple and versatile lab-on-a-chip system based on single-channel bisulfite conversion for DNA methylation analysis.

    Science.gov (United States)

    Yoon, Jaeyun; Park, Mi Kyoung; Lee, Tae Yoon; Yoon, Yong-Jin; Shin, Yong

    2015-09-07

    Miniaturized lab-on-a-chip (LOC) systems have been developed for genetic and epigenetic analyses in clinical applications because of advantages such as reduced sample size and reagent consumption, rapid processing speed, simplicity, and enhanced sensitivity. Despite tremendous efforts made towards developing LOC systems for use in the clinical setting, the development of LOC systems to analyze DNA methylation, which is an emerging epigenetic marker causing the abnormal silencing of genes including tumor suppressor genes, is still challenging because of the gold standard methods involving a bisulfite conversion step. Existing bisulfite conversion-based techniques are not suitable for clinical use due to their long processing time, labor intensiveness, and the purification steps involved. Here, we present a lab-on-a-chip system for DNA methylation analysis based on bisulfite conversion (LoMA-B), which couples a sample pre-processing module for on-chip bisulfite conversion and a label-free, real-time detection module for rapid analysis of DNA methylation status using an isothermal DNA amplification/detection technique. The methylation status of the RARβ gene in human genomic DNA extracted from MCF-7 cells was analyzed by the LoMA-B system within 80 min (except 16 h for sensor preparation) compared to conventional MS-PCR within 24 h. Furthermore, the LoMA-B system is highly sensitive and can detect as little as 1% methylated DNA in a methylated/unmethylated cell mixture. Therefore, the LoMA-B system is an efficient diagnostic tool for the simple, versatile, and quantitative evaluation of DNA methylation patterns for clinical applications.

  19. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J. [Tampella Power Inc., Tampere (Finland)

    1996-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  20. Implications of metric conversion.

    Science.gov (United States)

    Laros, R K

    1980-11-01

    The international scientific community is rapidly achieving conversion to the metric system, and the Système International (SI system) has been chosen for use by health scientists. Because the United States remains 1 of only 4 countries not now using part or all of the SI system, there is now a systematic effort toward rapid conversion. Although most of the SI system is not controversial, several SI units are highly so. Examples include joules instead of calories, pascals instead of millimeters of mercury, and moles per liter instead of milligrams per 100 milliliters. Obstetrician-gynecologists need to be familiar with the SI units and to voice their feelings about the various controversial units. There are decisions still to be made, and the time for discussion and advice is now.

  1. Transition age youth in publicly funded systems: identifying high-risk youth for policy planning and improved service delivery.

    Science.gov (United States)

    Heflinger, Craig Anne; Hoffman, Cheri

    2008-10-01

    Youth with Serious Emotional Disturbances (SED) face many challenges as they approach the transition to adulthood and adult services. This study examines publicly funded transition-age youth in order to describe the numbers and type of youth in need of policy and service planning in one state. Using Medicaid enrollment and claims/encounter data, youth with high risk of transition difficulties were identified in the following groups: SED, state custody/foster care or risk of custody, users of intensive or frequent mental health services, or having diagnoses of major mental disorders, conduct disorders, or developmental disabilities. Almost one quarter of all enrolled 14 to 17-year olds met criteria for at least one of the high risk groups, and three-quarters of these were youth with SED. High risk youth are described, with greater detail on those with SED, and implications for policy, services, and research are discussed.

  2. 7 CFR 3560.53 - Eligible use of funds.

    Science.gov (United States)

    2010-01-01

    ... housing is located. (j) Household furnishings (Section 514/516). For farm labor housing sections 514 and 516 only, funds may be used to purchase household furnishings. (k) Initial operating capital. Loan... section 502 properties. In accordance with § 3560.506, loan funds may be used to finance the conversion of...

  3. Pressure effect in syngas conversion to ethylene glycol. A behavior of rhodium-tributylphosphine-N-methylpyrrolidone system under 1000 atm

    Energy Technology Data Exchange (ETDEWEB)

    Murata, K.; Matsuda, A.; Masuda, T.; Watanabe, E.; Wada, K.

    1987-05-01

    In syngas (CO+H/sub 2/) conversion to ethylene glycol (EG), rhodium catalyst modified by tributylphosphine (P/sup n/Bu/sub 3/) was found to be ca. 20 times more active under 1000 atm at 210/sup 0/C than under 500 atm. This unusual pressure effect was discussed on the basis of IR spectral data. 8 references, 2 figures.

  4. Conversion and Validation of Distribution System Model from a QSTS-Based Tool to a Real-Time Dynamic Phasor Simulator: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan; Baggu, Murali M.

    2017-04-11

    A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source to enable use by others.

  5. Voltage Gain Derivation Based on Energy-Balanced Criterion for a Novel Hybrid-Input PV-Wind Power Conversion System

    Directory of Open Access Journals (Sweden)

    Chih-Lung Shen

    2015-01-01

    Full Text Available This paper applies energy-balanced criterion to a novel hybrid-input PV-wind power conversion system (HPWPCS for voltage gain derivation. With the energy-balanced concept, complicated mathematical problems related to voltage gain derivation can be readily resolved. Based on the derived results, it is proven that the proposed HPWPCS is able to process two different kinds of renewable energy resources simultaneously. Even though the HPWPCS includes seven capacitors and three magnetic components, its voltage gain still can be found by the mathematical analysis. In the theoretical derivation, only the energy status of output inductor is dealt with such that complicated derivation procedure is avoided. This analysis method can also be applied to other hybrid green-energy conversion systems. In this paper, a 200 W 50 kHz prototype of HPWPCS is built and examined to verify the mathematical results.

  6. Process Design and Economics for the Production of Algal Biomass: Algal Biomass Production in Open Pond Systems and Processing Through Dewatering for Downstream Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Ryan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Markham, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kinchin, Christopher [National Renewable Energy Lab. (NREL), Golden, CO (United States); Grundl, Nicholas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tan, Eric C.D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Humbird, David [DWH Process Consulting, Denver, CO (United States)

    2016-02-17

    This report describes in detail a set of aspirational design and process targets to better understand the realistic economic potential for the production of algal biomass for subsequent conversion to biofuels and/or coproducts, based on the use of open pond cultivation systems and a series of dewatering operations to concentrate the biomass up to 20 wt% solids (ash-free dry weight basis).

  7. Engineering manual. A practical reference of design methods and data in building systems, chemical, civil, electrical, mechanical, and environmental engineering and energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Perry, R.H. (ed.)

    1976-01-01

    Following 3 chapters of general reference information for engineers which include mathematics and mathematical tables, heat transfer, fluid flow, and basic thermodynamics, and data on the chemical, mechanical, and physical properties of materials, 7 chapters of data and design methods for specific engineering fields, i.e., architectural or building systems, chemical, civil, electrical, mechanical, environmental, and for energy conversion are presented. A subject index is included. (LCL)

  8. Power energy. Systems for energy conversion. Compact knowledge for study and profession. 5. rev. and enl. ed.; Energietechnik. Systeme zur Energieumwandlung. Kompaktwissen fuer Studium und Beruf

    Energy Technology Data Exchange (ETDEWEB)

    Zahoransky, Richard A. (ed.); Allelein, Hans-Josef; Bollin, Elmar; Oehler, Helmut; Schelling, Udo

    2010-07-01

    This textbook imparts to the reader a fundamental understanding for relations of energy conversion processes. It comprises the total spectra of energy engineering, starting with fundamentals of energy process engineering via description of operating power plants (all types) to energy distribution and - storage. Main topics are sustainable energy systems from renewable energy sources. combined systems (e.g. Gas/steam turbine power plants) and plants with cogeneration (e.g. modular cogeneration plants). A new chapter Kyoto-Protocol was created as a concept of emissions-free coal-fired power plants. A new wording for deregulation of energy markets was received. Numerous texts and graphs were been revised. Chapter 18 ''Deregulation of Energy Markets'' is newly revised. The 5th edition was actualized by new trends in energy engineering, chapter wind energy revised, and deregulation topics in the energy market extended. Due to its didactic concepts the book directs not only to students but also everybody, who is inerested into actual questions of energy engineering. (orig./GL)

  9. Optimization of supercritical phase and combined supercritical/subcritical conversion of lignocellulose for hexose production by using a flow reaction system.

    Science.gov (United States)

    Zhao, Yan; Lu, Wen-Jing; Wu, Hua-Yong; Liu, Jin-Wen; Wang, Hong-Tao

    2012-12-01

    A flow reaction system was utilized to investigate lignocellulose conversion using combined supercritical/subcritical conditions for hexose production. Initially, investigation of cellulose hydrolysis in supercritical water and optimization of reaction parameters were done. Oligosaccharide yields reached over 30% at cellulose concentrations of 3-5 gL(-1) and reaction times of 6-10s at 375 °C, and 2.5-4 gL(-1) and 8-10s at 380 °C. Temperatures above 380 °C were not appropriate for the supercritical phase in the combined process. Subsequently, conversion of lignocellulosic materials under combined supercritical/subcritical conditions was studied. Around 30% hexose was produced from corn stalks under the optimal parameters for supercritical (380 °C, 23-24 MPa, 9-10s) and subcritical (240 °C, 8-9 MPa, 45-50s) phases. Flow systems utilizing the combined supercritical/subcritical technology present a promising method for lignocellulosic conversion. The results of this study provide an important guide for the operational optimization and practical application of the proposed system. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Sperry Low Temperature Geothermal Conversion System, Phase I and Phase II. Volume IV. Field activities. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, C.

    1984-01-01

    This volume describes those activities which took place at the Sperry DOE Gravity Head plant site at the East Mesa Geothermal Reservoir near Holtville, California between February 1980, when site preparation was begun, and November 1982, when production well 87-6 was permanently abandoned. Construction activities were terminated in July 1981 following the liner collapse in well 87-6. Large amounts of program time manpower, materials, and funds had been diverted in a nine-month struggle to salvage the production well. Once these efforts proved futile, there was no rationale for continuing with the site work unless and until sufficient funding to duplicate well 87-6 was obtained. Activities reported here include: plant construction and pre-operational calibration and testing, drilling and completion of well 87-6, final repair effort on well 87-6, abandonment of well 87-6, and performance evaluation of well 87.6. (MHR)

  11. Fanconi Anemia Research Fund

    Science.gov (United States)

    ... Support Publications Fundraising News What is the Fanconi Anemia Research Fund? Fanconi anemia is an inherited disease that can lead to ... population. Lynn and Dave Frohnmayer started the Fanconi Anemia Research Fund, in 1989 to find effective treatments ...

  12. The funding black hole

    CERN Multimedia

    2008-01-01

    Two physics students at the University of Bristol have organised a petition against the recently-announced funding cut of 80 million by the body that funds physics research in the UK, the Science and Technology Facilities Council (STFC).

  13. Rating mutual funds

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Rangvid, Jesper

    2007-01-01

    obtained a risk-adjusted excess return that is approximately 3-4 percentage points higher per annum than if the funds with the highest costs had been invested in. We compare the atpRating with the Morningstar Rating. We show that one reason why the atpRating and the Morningstar Rating contain different...... the return of a fund in a certain year generally contains only little information about the future return that the fund will generate. Finally, we have information on the investments in different mutual funds made by a small subgroup of investors known to have been exposed to both the atp......We develop a new rating of mutual funds: the atpRating. The atpRating assigns crowns to each individual mutual fund based upon the costs an investor pays when investing in the fund in relation to what it would cost to invest in the fund's peers. Within each investment category, the rating assigns...

  14. Rating mutual funds

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Rangvid, Jesper

    obtained an annual risk-adjusted excess return that is approximately 3-4 percentage points higher per annum than if the funds with the highest costs had been invested in. We compare the atpRating with the Morningstar Rating. We show that one reason why the atpRating and the Morningstar Rating contain......, whereas the return of a fund in a certain year generally contains only little information about the future return that the fund will generate. Finally, we have information on the investments in different mutual funds made by a small subgroup of investors known to have been exposed to both the atp......We develop a new rating of mutual funds: the atpRating. The atpRating assigns crowns to each individual mutual fund based upon the costs an investor pays when investing in the fund in relation to what it would cost to invest in the fund's peers. Within each investment category, the rating assigns...

  15. Metrics, Dollars, and Systems Change: Learning from Washington State's Student Achievement Initiative to Design Effective Postsecondary Performance Funding Policies. A State Policy Brief

    Science.gov (United States)

    Jenkins, Davis; Shulock, Nancy

    2013-01-01

    The Student Achievement Initiative (SAI), adopted by the Washington State Board for Community and Technical Colleges in 2007, is one of a growing number of performance funding programs that have been dubbed "performance funding 2.0." Unlike previous performance funding models, the SAI rewards colleges for students' intermediate…

  16. 77 FR 27781 - Non-Competitive One-Year Extension With Funds for State Early Childhood Comprehensive Systems...

    Science.gov (United States)

    2012-05-11

    ... service systems. The State team activities associated with these plans, and the comprehensive systems they... systems-building activities with HRSA's Maternal, Infant, and Early Childhood Home Visiting (MIECHV...-building activities with early childhood investments within HRSA, including the MIECHV program, and with...

  17. Picking Funds with Confidence

    DEFF Research Database (Denmark)

    Grønborg, Niels Strange; Lunde, Asger; Timmermann, Allan

    identified ex-ante as being superior earn substantially higher risk-adjusted returns than top funds identified by conventional alpha ranking methods. Importantly, we find strong evidence of variation in the breadth of the set of funds identified as superior, as well as fluctuations in the style and industry...... exposures of such funds over time and across different volatility states....

  18. Clinical evaluation of digital angiographic system equipped with the Safire' flat-panel detector of a direct conversion type

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Yoshiaki; Miura, Yusuke; Goto, Keiichi [Shimadzu Corporation, Medical Systems Division, Research and Development, Kyoto (JP)] [and others

    2003-06-01

    This report presents a report on clinical evaluation of our newly developed flat-panel X-ray detector of a direct conversion type, designed to provide images of a resolution higher than, or at least equal to, that ensured by X-ray photographic films, in clinical digital X-ray cinematography. This new detector was named 'Safire' the acronym of 'Shimadzu advanced flat imaging receptor', emphasizing its high technological level, such as the capability to ensure high quality of images. The clinical evaluation of Shimadzu DIGITEX Premier digital angiography system, equipped with this new flat-panel X-ray detector of a direct conversion type, has been started in March, 2003, at the Kokura Memorial Hospital in Kyushu, Japan. (author)

  19. Development of a high temperature solar receiver for high-efficient thermionic conversion systems; Fukugo netsuden henkan system yo chokoon taiyo junetsuki no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Umeoka, T.; Naito, H.; Yugami, H.; Arashi, H. [Tohoku University, Sendai (Japan). Faculty of Engineering

    1996-10-27

    For thermionic conversion systems (TIC) using concentrated sunlight as heat source, the newly developed solar receiver was tested. Concentrated sunlight aims at the inner surface of the cavity type solar receiver. The emitter of TIC installed in the rear of the solar receiver is uniformly heated over 1700K by thermal radiation from the rear of the solar receiver, emitting thermion. Electric power is generated by collecting the thermion by collector. Mo is used as emitter material, however, because of poor heat absorption of Mo, high-absorptive TiC is used for heat absorption surface to heat Mo by thermal conduction from high-temperature TiC. Functionally gradient material (FGM) with an intermediate layer of gradient TiC/Mo ratios between TiC and Mo is used as emitter material. The emitter is thus uniformly heated at high temperatures of 1723{plus_minus}12K. As a result, the developed solar receiver is applicable to heat the emitter of TIC. Heat flux measurement at the graphite cavity clarified that cavity temperature of as high as 1780K and heat flow of 50W/cm{sup 2} are obtained at 4.7kW in input. 6 figs.

  20. Are fund of hedge fund returns asymmetric?

    OpenAIRE

    Lynch, Margaret; Hutson, Elaine; Stevenson, Max

    2004-01-01

    We examine the return distributions of 332 funds of hedge funds and associated indices. Over half of the sample is significantly skewed according to the skewness statistic, and these are split 50/50 positive and negative. However, we argue that the skewness statistic can lead to erroneous inferences regarding the nature of the return distribution, because the test statistic is based on the normal distribution. Using a series of tests that make minimal assumptions about the shape of the ...