WorldWideScience

Sample records for large nuclear-electric powerplants

  1. Nuclear Electric's central dose record service

    International Nuclear Information System (INIS)

    Goldfinch, E.P.; Mullarkey, D.T.; McWhan, A.W.; Risk, G.; Vaughan, L.

    1991-01-01

    This paper describes the conception, development and operation of the Nuclear Electric Central Dose Record Service, including the initial philosophy considered necessary for a database for a large multi-site organisation, the setting up of the data and current routine operation. Lessons learned are briefly described. CDRS holds 35,000 records in a high security environment. The database includes records of radiation doses received by contractor's employees working at Nuclear Electric sites as well as dose records and dose histories for classified and non classified Nuclear Electric employees. (Author)

  2. Change in Nuclear Electric

    International Nuclear Information System (INIS)

    Smart, D.

    1996-01-01

    Activities of Nuclear Electric company (Great Britain) in 1990-1995, aimed at privatization of certain NPPs and services, are considered. The company introduced commercial principles of work and control in all areas of expenditures. Great attention was paid to the work with personnel according to the program Investments in Personnel. All these initiatives resulted in increase in the total electricity production by 39% during the period of time under consideration in the 100% increase in the output per man/hour. This made it possible for the government to introduce its proposal on privatization of greater part of companies

  3. Reactors for nuclear electric propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades.

  4. Reactors for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Buden, D.; Angelo, J.A. Jr.

    1981-01-01

    Propulsion is the key to space exploitation and power is the key to propulsion. This paper examines the role of nuclear fission reactors as the primary power source for high specific impulse electric propulsion systems for space missions of the 1980s and 1990s. Particular mission applications include transfer to and a reusable orbital transfer vehicle from low-Earth orbit to geosynchronous orbit, outer planet exploration and reconnaissance missions, and as a versatile space tug supporting lunar resource development. Nuclear electric propulsion is examined as an indispensable component in space activities of the next two decades

  5. Nuclear Electric looks to the private sector

    International Nuclear Information System (INIS)

    Varley, James.

    1995-01-01

    The state-owned utility Nuclear Electric, which is responsible for nuclear power generation in England and Wales, was created in 1990 following withdrawal of nuclear from electricity privatisation. Having successfully made itself much more commercial, Nuclear Electric would like the freedom of operating in the private sector. (author)

  6. 18 CFR 287.101 - Determination of powerplant design capacity.

    Science.gov (United States)

    2010-04-01

    ... powerplant design capacity. For the purpose of section 103 of the Powerplant and Industrial Fuel Use Act of... powerplant design capacity. 287.101 Section 287.101 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE POWERPLANT AND INDUSTRIAL FUEL USE ACT OF...

  7. Super Spool: An Experiment in Powerplant Design

    Science.gov (United States)

    Kesler, Ronald

    1974-01-01

    Discusses the use of rubberbands, an empty wooden thread spool, two wooden matches, a wax washer, and a small nail to conduct an experiment or demonstration in powerplant design. Detailed procedures and suggested activities are included. (CC)

  8. Nuclear Electric Visitor Centres - Innovation and inspiration

    International Nuclear Information System (INIS)

    Fenton, Bob

    1998-01-01

    Full text: This eight minute video demonstrates the approach taken by Nuclear Electric to exhibitions that are open to the public. The information is given both visually - with excerpts from some of the attractions on display at the centres - and in comments from interviews with visitors, the centre guides and the man responsible for many of the exhibits featured in the video. on one side are the schoolchildren who are visiting the exhibition and are seen both playing and learning as they press buttons, watch videos, 'meet' Michael Faraday, and learn about radiation - its disposal and its safe transportation. The headmaster of the school is interviewed and explains that the exhibition is helping his children understand the importance of electricity to their world. on the other side is Jackie Lucas, the visitor centre manager, explaining what the public make of the exhibition. We see her staff greeting the children and helping them to understand the show. The designer of the exhibition, Len Upton explains how you go about making an exhibition such as this both informative and fun. Also interviewed is the man behind many of the exhibitions featured at Nuclear Electric's visitor centres up and down the country, Nicholas Mullane. He explains the purpose of the exhibition and what messages it imparts. The video is presented in split-screen or composite format, whereby the interviewee and children are often presented together. Excerpts from the various videos on display are presented as both how they are seen from the floor, as well as the full screen effect of the various programmes. The video gives much of the feeling of fun to be gained at the exhibition, as well as showing the educational benefits to be gained from a couple of hours at one of Nuclear Electric's visitor centres. Copies of the video can be obtained from Bob Fenton at Nuclear Electric. (Fax: ++44 1 452 652 443). (author)

  9. Basic recognition on safety of nuclear electric power generation

    International Nuclear Information System (INIS)

    Miyazaki, Keiji

    1995-01-01

    The safety of nuclear electric power generation is not to inflict radiation damage on public. Natural radiation is about 1 mSv every year. As far as the core melting on large scale does not occur, there is not the possibility of exerting serious radiation effect to public. The way of thinking on ensuring the safety is defense in depth. The first protection is the prevention of abnormality, the second protection is the prevention of accidents, and the third protection is the relaxation of effect. As design base accidents, the loss of coolant accident due to the breakdown of inlet pipings of reactors and the breaking of fine tubes in steam generators are included. The suitability of location is evaluated. As the large scale accidents of nuclear power stations in the past, Chernobyl accident and Three Mile Island accident are explained. The features of the countermeasures to the accident in Mihama No. 2 plant are described. The countermeasures to severe accidents, namely accident management and general preventive maintenance are explained. The background of the nonconfidence feeling to nuclear electric power generation and the importance of opening information to public are shown. (K.I.)

  10. NASA program planning on nuclear electric propulsion

    International Nuclear Information System (INIS)

    Bennett, G.L.; Miller, T.J.

    1992-03-01

    As part of the focused technology planning for future NASA space science and exploration missions, NASA has initiated a focused technology program to develop the technologies for nuclear electric propulsion and nuclear thermal propulsion. Beginning in 1990, NASA began a series of interagency planning workshops and meetings to identify key technologies and program priorities for nuclear propulsion. The high-priority, near-term technologies that must be developed to make NEP operational for space exploration include scaling thrusters to higher power, developing high-temperature power processing units, and developing high power, low-mass, long-lived nuclear reactors. 28 refs

  11. Status report on nuclear electric propulsion systems

    Science.gov (United States)

    Stearns, J. W.

    1975-01-01

    Progress in nuclear electric propulsion (NEP) systems for a multipayload multimission vehicle needed in both deep-space missions and a variety of geocentric missions is reviewed. The space system power level is a function of the initial launch vehicle mass, but developments in out-of-core nuclear thermionic direct conversion have broadened design options. Cost, design, and performance parameters are compared for reusable chemical space tugs and NEP reusable space tugs. Improvements in heat pipes, ion engines, and magnetoplasmadynamic arc jet thrust subsystems are discussed.

  12. NASA's nuclear electric propulsion technology project

    International Nuclear Information System (INIS)

    Stone, J.R.; Sovey, J.S.

    1992-07-01

    The National Aeronautics and Space Administration (NASA) has initiated a program to establish the readiness of nuclear electric propulsion (NEP) technology for relatively near-term applications to outer planet robotic science missions with potential future evolution to system for piloted Mars vehicles. This program was initiated in 1991 with a very modest effort identified with nuclear thermal propulsion (NTP); however, NEP is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. The NEP Program will establish the feasibility and practicality of electric propulsion for robotic and piloted solar system exploration. The performance objectives are high specific impulse (200 greater than I(sub sp) greater than 10000 s), high efficiency (over 0.50), and low specific mass. The planning for this program was initially focussed on piloted Mars missions, but has since been redirected to first focus on 100-kW class systems for relatively near-term robotic missions, with possible future evolution to megawatt-and multi-megawatt-class systems applicable to cargo vehicles supporting human missions as well as to the piloted vehicles. This paper reviews current plans and recent progress for the overall nuclear electric propulsion project and closely related activities. 33 refs

  13. CO2 emissions of nuclear electricity generation

    International Nuclear Information System (INIS)

    Wissel, Steffen; Mayer-Spohn, Oliver; Fahl, Ulrich; Blesl, Markus; Voss, Alfred

    2008-01-01

    A survey of LCA studies on nuclear electricity generation revealed life cycle CO 2 emissions ranging between 3 g/kWhe to 60 g/kWhe and above. Firstly, this paper points out the discrepancies in studies by estimating the CO 2 emissions of nuclear power generation. Secondly, the paper sets out to provide critical review of future developments of the fuel cycle for light water reactors and illustrates the impact of uncertainties on the specific CO 2 emissions of nuclear electricity generation. Each step in the fuel cycle will be considered and with regard to the CO 2 emissions analysed. Thereby different assumptions and uncertainty levels are determined for the nuclear fuel cycle. With the impacts of low uranium ore grades for mining and milling as well as higher burn-up rates future fuel characteristics are considered. Sensitivity analyses are performed for all fuel processing steps, for different technical specifications of light water reactors as well as for further external frame conditions. (authors)

  14. Current training initiatives at Nuclear Electric plc

    International Nuclear Information System (INIS)

    Fowler, C.D.

    1993-01-01

    Nuclear Electric, one of the three generating companies to emerge from the demise of the U.K.'s Central Electricity Generating Board (CEGB), owns and operates the commercial nuclear power stations in England and Wales. The U.K. government proscribed further construction beyond Sizewell B, the United Kingdom's first pressurized water reactor (PWR) station, pending the outcome of a review of the future of nuclear power to be held in 1994. The major challenges facing Nuclear Electric at its formation in 1990 were therefore to demonstrate that nuclear power is safe, economical, and environmentally acceptable and to complete the PWR station under construction on time and within budget. A significant number of activities were started that were designed to increase output, reduce costs, and ensure that the previous excellent safety standards were maintained. A major activity was to reduce the numbers of staff employed, with a recognition from the outset that this reduction could only be achieved with a significant human resource development program. Future company staff would have to be competent in more areas and more productive. This paper summarizes some of the initiatives currently being pursued throughout the company and the progress toward ensuring that staff with the required competences are available to commission and operate the Sizewell B program in 1994

  15. 14 CFR 23.939 - Powerplant operating characteristics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Powerplant operating characteristics. 23... General § 23.939 Powerplant operating characteristics. (a) Turbine engine powerplant operating characteristics must be investigated in flight to determine that no adverse characteristics (such as stall, surge...

  16. Nuclear Powerplant Safety: Source Terms. Nuclear Energy.

    Science.gov (United States)

    Department of Energy, Washington, DC. Nuclear Energy Office.

    There has been increased public interest in the potential effects of nuclear powerplant accidents since the Soviet reactor accident at Chernobyl. People have begun to look for more information about the amount of radioactivity that might be released into the environment as a result of such an accident. When this issue is discussed by people…

  17. Designing powerplants for today's competitive environment

    International Nuclear Information System (INIS)

    Makansi, J.

    1994-01-01

    Deregulation continues to unfold. Certainty about what the impact will be is as scarce as new US powerplant development opportunities. But one thing industry observers seem clear on is that the priorities for powerplant design will shift as competitive forces are rolled out. Powerplants will have to be developed, designed, and operated as a bottom-line business, not as part of a regulated industry. Thus, the design must enable the facility to accomplish this goal. In the emerging fully competitive environment, that bottom line applies to both the kilowatt and the kilowatt-hour. The entrepreneurial and business skills and talents of the independent power producer (IPP) have mostly been brought to bear on capital costs and project development thus far, with electricity sold under long-term power-purchase agreements. If retail wheeling takes hold, future plants must also be designed to merchandise power to a variety of customers scattered around the grid. This article provides insight into how powerplant design will accommodate new priorities

  18. Evolutionary use of nuclear electric propulsion

    International Nuclear Information System (INIS)

    Hack, K.J.; George, J.A.; Riehl, J.P.; Gilland, J.H.

    1990-01-01

    Evolving new propulsion technologies through a rational and conscious effort to minimize development costs and program risks while maximizing the performance benefits is intuitively practical. A phased approach to the evolution of nuclear electric propulsion from use on planetary probes, to lunar cargo vehicles, and finally to manned Mars missions with a concomitant growth in technology is considered. Technology levels and system component makeup are discussed for nuclear power systems and both ion and magnetoplasmadynamic thrusters. Mission scenarios are described, which include analysis of a probe to Pluto, a lunar cargo mission, Martian split, all-up, and quick-trip mission options. Evolutionary progression of the use of NEP in such missions is discussed. 26 refs

  19. Nuclear-electric power in space

    International Nuclear Information System (INIS)

    Truscello, V.C.; Davis, H.S.

    1984-01-01

    Because direct-broadcast satellites, air-traffic-control radar satellites, industrial processing on subsequent versions of the space station, and long range excursions to other planets using nuclear-electric propulsion systems, all space missions for which current power-supply systems are not sufficient. NASA and the DOE therefore have formed a joint program to develop the technology required for nuclear-reactor space power plants. After investigating potential space missions in the given range, the project will develop the technology to build such systems. High temperatures pose problems, ''hot shoes'' and ''cold shoes'', a Stirling engine dynamic system, and critical heat-transfer problems are all discussed. The nuclear reactor system for space as now envisioned is schematicized

  20. NASA's progress in nuclear electric propulsion technology

    International Nuclear Information System (INIS)

    Stone, J.R.; Doherty, M.P.; Peecook, K.M.

    1993-01-01

    The National Aeronautics and Space Administration (NASA) has established a requirement for Nuclear Electric Propulsion (NEP) technology for robotic planetary science mission applications with potential future evolution to systems for piloted Mars vehicles. To advance the readiness of NEP for these challenging missions, a near-term flight demonstration on a meaningful robotic science mission is very desirable. The requirements for both near-term and outer planet science missions are briefly reviewed, and the near-term baseline system established under a recent study jointly conducted by the Lewis Research Center (LeRC) and the Jet Propulsion Laboratory (JPL) is described. Technology issues are identified where work is needed to establish the technology for the baseline system, and technology opportunities which could provide improvement beyond baseline capabilities are discussed. Finally, the plan to develop this promising technology is presented and discussed. 19 refs

  1. Nuclear Electric Propulsion Application: RASC Mission Robotic Exploration of Venus

    Science.gov (United States)

    McGuire, Melissa L.; Borowski, Stanley K.; Packard, Thomas W.

    2004-01-01

    The following paper documents the mission and systems analysis portion of a study in which Nuclear Electric Propulsion (NEP) is used as the in-space transportation system to send a series of robotic rovers and atmospheric science airplanes to Venus in the 2020 to 2030 timeframe. As part of the NASA RASC (Revolutionary Aerospace Systems Concepts) program, this mission analysis is meant to identify future technologies and their application to far reaching NASA missions. The NEP systems and mission analysis is based largely on current technology state of the art assumptions. This study looks specifically at the performance of the NEP transfer stage when sending a series of different payload package point design options to Venus orbit.

  2. Safety culture development in nuclear electric plc

    International Nuclear Information System (INIS)

    Gibson, G.P.; Low, M.B.J.

    1995-01-01

    Nuclear Electric plc (NE) has always given the highest priority to safety. However, past emphasis has been directed towards ensuring safety thorough engineering design and hazard control procedures. Whilst the company did achieve high safety standards, particularly with respect to accidents, it was recognized that further improvements could be obtained. Analysis of the safety performance across a wide range of industries showed that the key to improving safety performance lay in developing a strong safety culture within the company. Over the last five years, NE has made great strides to improve its safety culture. This has resulted in a considerable improvement in its measured safety performance indicators, such as the number of incidents at international nuclear event scale (INES) rating 1, the number of lost time accidents and the collective radiation dose. However, despite this success, the company is committed to further improvement and a means by which this process becomes self-sustaining. In this way the company will achieve its prime goal, to ''ensure the safety of people, plant and the environment''. The paper provides an overview of the development of safety culture in NE since its formation in November 1989. It describes the research and international developments that have influenced the company's understanding of safety culture, the key initiatives that the company has undertaken to enhance its safety culture and the future initiatives being considered to ensure continual improvement. (author). 5 refs, 2 figs, 2 tabs

  3. Regional analysis of the nuclear-electricity

    International Nuclear Information System (INIS)

    Parera, M. D.

    2011-11-01

    In this study was realized a regional analysis of the Argentinean electric market contemplating the effects of regional cooperation, the internal and international interconnections; and the possibilities of insert of new nuclear power stations were evaluated in different regions of the country, indicating the most appropriate areas to carry out these facilities to increase the penetration of the nuclear energy in the national energy matrix. Also was studied the interconnection of the electricity and natural gas markets, due to the existent linking among both energy forms. With this purpose the program Message (Model for energy supply strategy alternatives and their general environmental impacts) was used, promoted by the International Atomic Energy Agency. This model carries out an economic optimization level country, obtaining the minimum cost as a result for the modeling system. The division for regions realized by the Compania Administradora del Mercado Mayorista Electrico (CAMMESA) was used, which divides to the country in eight regions. They were considered the characteristics and necessities of each one of them, their respective demands and offers of electric power and natural gas, as well as their existent and projected interconnections, composed by the electric lines and gas pipes. According to the results obtained through the model, the nuclear-electricity is a competitive option. (Author)

  4. Robots in P.W.R. nuclear powerplants

    International Nuclear Information System (INIS)

    Dubourg, M.

    1987-01-01

    The satisfactory operation of 37 900-MWe PWR powerplants in France, Belgium and South-Africa and the start-up of 1300 MWe powerplants allowed the development of a wide range of automatic units and robots for the periodic maintenance of nuclear plants, reducing the risk of ionizing radiation for the personnel. A large number of automated tools have been built. Among them: - inspection and maintenance systems for the tube bundle of steam generators, - robotized arms ROTETA and ROMEO for the heavy maintenance and delicate operations such as tube extraction or shot peening of tubes to improve their resistance to corrosion; - the versatile manipulator T.A.M. with electrically controlled articulations. The development of functionally versatile tools and robots and the integration of new technologies such as 3-D vision allowed the construction of the self-guided vehicle FRASTAR capable of moving within a nuclear building and in a cluttered environment. This vehicle includes means for avoiding isolated obstacles and can move on stairs [fr

  5. Issues for the electric utilities posed by DT tokamak fusion powerplants

    International Nuclear Information System (INIS)

    Roth, J.R.

    1990-01-01

    The DT tokamak is the mainline approach to magnetic fusion energy in all industrialized countries with a major commitment to fusion research. It achieved this status largely through historical accident and not as the result of considered choice among alternatives. After twenty-five years of intensive tokamak research, it is appropriate to ask whether the path down which the tokamak concept is leading the fusion community is the way to an acceptable powerplant for the electric utilities, or an aberration which should be replaced with an approach more promising in the long term. Issues surrounding the DT tokamak can be grouped in three broad areas: physics; safety/environmental; and engineering/economic. In addition to these problems, detailed engineering design studies of DT tokamak fusion powerplants over a twenty year period have revealed a number of additional problems. Most of thee are related to the presence of tritium and energetic neutron fluxes, which tend to make the cost of electricity of DT tokamaks higher than that of fossil or fission powerplants. These safety and economic issues of the DT tokamak powerplant also appear to be intractable, and have not been made to go away by twenty years of progressively more detailed and extensive engineering design studies

  6. Rising to the challenge - the changing face of Nuclear Electric

    International Nuclear Information System (INIS)

    Hawley, R.

    1994-01-01

    When the electricity generation industry in the United Kingdom was privatised in 1989, the Government decided to withdraw the nuclear generating capacity from the programme. Nuclear power's poor track record on construction, operating and production costs and apparently crippling liabilities for decommissioning and radioactive waste management made it an unlikely success on the financial markets. Nuclear Electric was then formed, a public limited company, wholly owned by the Government to run England's and Wales' nuclear power industry. In four years since then the management and staff of Nuclear Electric have worked hard to improve performance; output has risen, costs are down and productivity has doubled. The Sizewell B power station has been completed remarkably ahead of time and within budget. It is argued that, with further improvements, Nuclear Electric may also be profitably privatised in the future should the Government wish it. (UK)

  7. Nuclear Electric - four years on and right on course

    International Nuclear Information System (INIS)

    Hawley, R.

    1994-01-01

    Since the Government's decision, four years ago, to withdraw the nuclear stations from the electricity supply industry privatisation, and place a moratorium on the construction of further nuclear plant, the newly formed nuclear generators, Nuclear Electric and Scottish Nuclear, have risen to the challenge of proving that nuclear power can be as competitive in the United Kingdom as it is elsewhere in the world. The Chief Executive of Nuclear Electric documents changes which have taken place within the organisation since privatisation, presenting data on output and market share and productivity to back his argument. (UK)

  8. Nuclear electric power safety, operation, and control aspects

    CERN Document Server

    Knowles, J Brian

    2013-01-01

    Assesses the engineering of renewable sources for commercial power generation and discusses the safety, operation, and control aspects of nuclear electric power From an expert who advised the European Commission and UK government in the aftermath of Three Mile Island and Chernobyl comes a book that contains experienced engineering assessments of the options for replacing the existing, aged, fossil-fired power stations with renewable, gas-fired, or nuclear plants. From geothermal, solar, and wind to tidal and hydro generation, Nuclear Electric Power: Safety, Operation, and Control Aspects ass

  9. Thermionic reactor power conditioner design for nuclear electric propulsion.

    Science.gov (United States)

    Jacobsen, A. S.; Tasca, D. M.

    1971-01-01

    Consideration of the effects of various thermionic reactor parameters and requirements upon spacecraft power conditioning design. A basic spacecraft is defined using nuclear electric propulsion, requiring approximately 120 kWe. The interrelationships of reactor operating characteristics and power conditioning requirements are discussed and evaluated, and the effects on power conditioner design and performance are presented.

  10. Advanced nuclear turbojet powerplant characteristics summary for supersonic aircraft

    International Nuclear Information System (INIS)

    Larson, John W.

    1959-01-01

    The estimated powerplant characteristics of an advanced nuclear powerplant intended for use in a nuclear supersonic manned airplane is contained in this report. This nuclear powerplant consists of a 575 MW, high temperature, lithium-cooled, solid fuel element-type reactor coupled to six turbojet engines especially designed for a supersonic nuclear airplane. The lithium coolant passes from the reactor at 2000F directly to the engine radiators without the use of an intermediate heat exchanger. The engines are fitted with burners enabling the thrust produced by the nuclear powerplant to be augmented by the use of chemical fuel for the take-off, transonic acceleration and landing portions of the flight. The powerplant components have been selected for a maximum thrust-to-weight ratio at Mach 3 and 55,000 feet altitude on nuclear heat only operation compromised for net thrust produced with chemical fuel augmentation during the transonic portion of flight. The power plant data presented, therefore, are primarily applicable to an all supersonic mission on nuclear heat alone. The powerplant data presented in this report are an extension of data contained in PWAC-243, 'NJ-14 All-Nuclear Supersonic Bomber Powerplant Characteristics Summary, March 11, 1958', to a higher reactor power. In addition, the engine compressor pressure ratio has been increased to improve transonic thrust characteristics. Weight data are tabulated for the 575 MW powerplant. The engine envelope based on preliminary radiator size estimates is illustrated. A liquid metal system flow schematic and piping data are included. Shield information including reactor shield outline, assumptions, weights, and direct dose pattern at 50 feet is also included. Estimated performance on nuclear heat only operation and nuclear heat plus burning is presented for an envelope of flight conditions.

  11. Additional improvements needed in physical security at nuclear powerplants

    International Nuclear Information System (INIS)

    1983-01-01

    Since the middle 1970's, the Nuclear Regulatory Commission and powerplant operators have taken measures to reduce the vulnerability of powerplants to attempted acts of sabotage. GAO's evaluation disclosed that further improvements can be made by screening nuclear plant employees to reduce the number of potential saboteurs and strengthening the physical security systems to ensure their compatibility with other plant safety systems. The Commission has taken two initiatives addressing these improvements. Therefore, GAO is not making recommendations at this time

  12. Projected cost comparison of nuclear electricity

    International Nuclear Information System (INIS)

    Juhn, P.E.; Hu, C.W.

    2000-01-01

    Comparison of electricity generation costs has been done in the late years through a large co-operation between several organisations. The studies are aiming to provide reliable comparison of electricity generating costs of nuclear and conventional base load power plants. This paper includes the result of the joint IAEA/OECD study published in 1997. (author)

  13. Costs and competitiveness of nuclear electricity

    International Nuclear Information System (INIS)

    Bennett, L.L.; Woite, G.

    1995-01-01

    The experienced and projected future construction costs and electricity generation costs of nuclear and fossil fired power plants are reviewed and compared. On the basis of actual operating experience, nuclear power has been demonstrated to be economically competitive with other base load generation options, and international studies project that this economic competitiveness will be largely maintained in the future, over a range of conditions and in a number of countries. However, retaining and improving this competitiveness position requires concerted efforts to ensure that nuclear plants are constructed within schedule and budget, and are operated reliably and efficiently. Relevant cost impacting factors are identified, and conclusions for successful nuclear power plant construction and operation are drawn. The desire to attain sustainable development with balanced resource use and control of the environmental and climatic impacts of energy systems could lead to renewed interest in nuclear power as an energy source that does not emit greenhouse gases, thus contributing to a revival of the nuclear option. In this regard also, mitigation of emissions from fossil fuelled power plants could lead to restrictions of fossil fuel use and/or result in higher costs of fossil based generation, thus improving the economic competitiveness of nuclear power. (author). 19 refs, 7 figs, 2 tabs

  14. Robotic planetary mission benefits from nuclear electric propulsion

    International Nuclear Information System (INIS)

    Kelley, J.H.; Yen, C.L.

    1992-01-01

    Several interesting planetary missions are either enabled or significantly enhanced by nuclear electric propulsion (NEP) in the 50 to 100 kW power range. These missions include a Pluto Orbiter/Probe with an 11-year flight time and several years of operational life in orbit versus a ballistic very fast (13 km/s) flyby which would take longer to get to Pluto and would have a very short time to observe the planet. (A ballistic orbiter would take about 40 years to get to Pluto.) Other missions include a Neptune Orbiter/Probe, a Jupiter Grand Tour orbiting each of the major moons in order, a Uranus Orbiter/Probe, a Multiple Mainbelt Asteroid Rendezvous orbiting six selected asteroids, and a Comet Nucleus Sample Return. This paper discusses potential missions and compares the nuclear electric propulsion option to the conventional ballistic approach on a parametric basis

  15. Facts against nuclear electricity generation. 2. enlarged ed.

    International Nuclear Information System (INIS)

    Buechele, C.

    1986-01-01

    The book destroys a legend. The nuclear cartel still goes on telling the tale of safety, environmental compatibility and economic efficiency of nuclear electricity generation. But nothing in this story stands the test: Bare facts destroy the legend. Up to now, only insiders have been able to state counterarguments. The book in hand now presents in a nutshell all results and experience and facts to be brought forward against nuclear electricity generation. The material is presented in a problem-oriented, reliable and comprehensible manner. Anyone who long since suspected lies and malinformation of the public will step by step find the arguments justifying his suspicion. In an annex, Harald Gaber explains the Chernobyl disaster and its consequences. A literature index with comments is a helpful guide for further reading. (orig.) [de

  16. Nuclear Electric and the environment 1990-1993

    International Nuclear Information System (INIS)

    1993-01-01

    The process of generating electricity has an impact on the environment in which we live, whatever form of generation is used. Nuclear generation, while it has the advantage of producing virtually no acid or greenhouse gases, is no exception. What Nuclear Electric can do, as the producer of over one-fifth of the electricity supplied in England and Wales, is to minimise and to control the adverse effects of our operations on the environment. This first environmental report covers the period since Nuclear Electric was formed in March 1990. It describes what we are doing to harmonise our activities both radiological and non-radiological with the natural environment, to limit environmental impacts and to make efficient use of natural resources and gives targets that we have set ourselves which we will report back on in future annual environmental reports. (author)

  17. Scoping calculations of power sources for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Difilippo, F.C.

    1994-05-01

    This technical memorandum describes models and calculational procedures to fully characterize the nuclear island of power sources for nuclear electric propulsion. Two computer codes were written: one for the gas-cooled NERVA derivative reactor and the other for liquid metal-cooled fuel pin reactors. These codes are going to be interfaced by NASA with the balance of plant in order to making scoping calculations for mission analysis

  18. Nuclear electric propulsion mission engineering study. Volume 2: Final report

    Science.gov (United States)

    1973-01-01

    Results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions are summarized. Critical technologies associated with the development of nuclear electric propulsion (NEP) are assessed, along with the impact of its availability on future space programs. Outer planet and comet rendezvous mission analysis, NEP stage design for geocentric and interplanetary missions, NEP system development cost and unit costs, and technology requirements for NEP stage development are studied.

  19. Multimission nuclear electric propulsion system for outer planet exploration missions

    International Nuclear Information System (INIS)

    Mondt, J.F.

    1981-01-01

    A 100-kW reactor power system with a specific mass of 15 to 30 kg/kW/sub e/ and an electric thrust system with a specific mass of 5 to 10 kg/kW/sub e/ can be combined into a nuclear electric propulsion system. The system can be used for outer planet missions as well as earth orbital transfer vehicle missions. 5 refs

  20. Nuclear powerplant standardization: light water reactors. Volume 2. Appendixes

    International Nuclear Information System (INIS)

    1981-06-01

    This volume contains working papers written for OTA to assist in preparation of the report, NUCLEAR POWERPLANT STANDARDIZATION: LIGHT WATER REACTORS. Included in the appendixes are the following: the current state of standardization, an application of the principles of the Naval Reactors Program to commercial reactors; the NRC and standardization, impacts of nuclear powerplant standardization on public health and safety, descriptions of current control room designs and Duke Power's letter, Admiral Rickover's testimony, a history of standardization in the NRC, and details on the impact of standardization on public health and safety

  1. Development costs for a nuclear electric propulsion stage.

    Science.gov (United States)

    Mondt, J. F.; Prickett, W. Z.

    1973-01-01

    Development costs are presented for an unmanned nuclear electric propulsion (NEP) stage based upon a liquid metal cooled, in-core thermionic reactor. A total of 120 kWe are delivered to the thrust subsystem which employs mercury ion engines for electric propulsion. This study represents the most recent cost evaluation of the development of a reactor power system for a wide range of nuclear space power applications. These include geocentric, and outer planet and other deep space missions. The development program is described for the total NEP stage, based upon specific development programs for key NEP stage components and subsystems.

  2. Nuclear electric propulsion mission engineering study. Volume 1: Executive summary

    Science.gov (United States)

    1973-01-01

    Results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions are summarized. Critical technologies associated with the development of nuclear electric propulsion (NEP) are assessed. Outer planet and comet rendezvous mission analysis, NEP stage design for geocentric and interplanetary missions, NEP system development cost and unit costs, and technology requirements for NEP stage development are studied. The NEP stage design provides both inherent reliability and high payload mass capability. The NEP stage and payload integration was found to be compatible with the space shuttle.

  3. Static and dynamic high power, space nuclear electric generating systems

    International Nuclear Information System (INIS)

    Wetch, J.R.; Begg, L.L.; Koester, J.K.

    1985-01-01

    Space nuclear electric generating systems concepts have been assessed for their potential in satisfying future spacecraft high power (several megawatt) requirements. Conceptual designs have been prepared for reactor power systems using the most promising static (thermionic) and the most promising dynamic conversion processes. Component and system layouts, along with system mass and envelope requirements have been made. Key development problems have been identified and the impact of the conversion process selection upon thermal management and upon system and vehicle configuration is addressed. 10 references

  4. Groundwater impact assessment report for the 284-WB Powerplant Ponds

    International Nuclear Information System (INIS)

    Alexander, D.J.; Johnson, V.G.; Lindsey, K.A.

    1993-09-01

    As required by the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement Milestone M-17-00A), this report assesses the impact of wastewater discharged to the 284-WB Powerplant Ponds on groundwater quality. The assessment reported herein expands upon the initial analysis conducted between 1989 and 1990 for the Liquid Effluent Study Final Project Plan

  5. Britain's Nuclear Electric pursues a major programme to enhance safety

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The UK state-owned nuclear utility, Nuclear Electric, is actively pursuing a major initiative inherited from its predecessor the Central Electricity Generating Board, known as the Station Enhancement Programme. The Enhancement Programme is a multi-million pound project and covers all Nuclear Electric's stations (including relevant aspects of the de-commissioning site at Berkeley). Its fundamental objective is to enhance the arrangements, practices and attitudes on the power stations to create an overall environment likely to promote ever safer and more reliable operation, and to take full account of the best international practices. The four year programme started in the spring of 1989, and is expected to be completed in 1993. Key elements of the programme include quality assurance based management systems; improvements to site and plant material conditions; a more formal approach to training; additional resources and controls to aid the management of maintenance defects; higher profile for the feedback of operational experience; management targets; a station evaluation programme; and formal feedback of lessons learned from the IAEA operational and safety review team visit to the Oldbury-on-Severn station in 1989. (author)

  6. Feasibility of the recent Russian nuclear electric propulsion concept: 2010

    International Nuclear Information System (INIS)

    Zakirov, Vadim; Pavshook, Vladimir

    2011-01-01

    Highlights: → The paper focuses on feasibility of the Russian nuclear electric propulsion (NEP) concept. → The Russian NEP concept is based on the past experience and is, therefore, technically feasible. → The big concern is that the program will be cancelled due to non-technical issues. - Abstract: The paper introduces recent Russian nuclear electric propulsion (NEP) concept for space exploration. The concept advantages are listed along with future missions. The current development status for the two main enabling technologies is presented and the feasibility analysis of the up-to-date experience is performed. The main features of NEP concept are discussed. Revision of these features and available technologies demonstrates that the NEP concept is a logical continuation of the previous efforts by the former Soviet Union. Because no breakthrough technologies are needed for NEP development while the existing technologies only need to be adapted to the megawatt (MW) class NEP the development is considered technically feasible, low risk program likely to succeed unless cancelled by the listed non-technical reasons. Successful NEP space vehicle development is going to bring practical space exploration of solar system to the new level as well as require supplementary payload program, supporting monitoring and communication radar networks. Nuclear safety during future NEP missions can be ensured by adherence to the United Nations guidelines in the same way it was done during the Soviet Topaz Nuclear Power System (NPS) missions.

  7. The cost of nuclear electricity: France after Fukushima

    International Nuclear Information System (INIS)

    Boccard, Nicolas

    2014-01-01

    The Fukushima disaster has lead the French government to release novel cost information relative to its nuclear electricity program allowing us to compute a levelized cost. We identify a modest escalation of capital cost and a larger than expected operational cost. Under the best scenario, the cost of French nuclear power over the last four decades is 59€/MWh (at 2010 prices) while in the worst case it is 83€/MWh. On the basis of these findings, we estimate the future cost of nuclear power in France to be at least 76€/MWh and possibly 117€/MWh. A comparison with the US confirms that French nuclear electricity nevertheless remains cheaper. Comparisons with coal, natural gas and wind power are carried out to find the advantage of these. - Highlights: • We compute the levelized cost of French nuclear power over 40 years using a novel court of audit report. • We include R and D, technology development, fissile fuel, financing cost, decommissioning and the back-end cycle. • We find a mild capital cost escalation and a high operation cost driven by a low fleet availability. • The levelized cost ranges between 59 and 83€/MWh (at 2010 prices) and compares favorably to the US. • A tentative cost for future nuclear power ranges between 76 and 117€/MWh and compares unfavorably against alternative fuels

  8. Feasibility of the recent Russian nuclear electric propulsion concept: 2010

    Energy Technology Data Exchange (ETDEWEB)

    Zakirov, Vadim, E-mail: v.zakirov@mail.tsinghua.edu.c [Room 3121, Yifu Building, School of Aerospace, Tsinghua University, Haidian District, Beijing 100084 (China); Pavshook, Vladimir, E-mail: vap_ki@mail.r [Russian Research Center ' Kurchatov Institute' , Kurchatov Sq. 1, Moscow 123182 (Russian Federation)

    2011-05-15

    Highlights: The paper focuses on feasibility of the Russian nuclear electric propulsion (NEP) concept. The Russian NEP concept is based on the past experience and is, therefore, technically feasible. The big concern is that the program will be cancelled due to non-technical issues. - Abstract: The paper introduces recent Russian nuclear electric propulsion (NEP) concept for space exploration. The concept advantages are listed along with future missions. The current development status for the two main enabling technologies is presented and the feasibility analysis of the up-to-date experience is performed. The main features of NEP concept are discussed. Revision of these features and available technologies demonstrates that the NEP concept is a logical continuation of the previous efforts by the former Soviet Union. Because no breakthrough technologies are needed for NEP development while the existing technologies only need to be adapted to the megawatt (MW) class NEP the development is considered technically feasible, low risk program likely to succeed unless cancelled by the listed non-technical reasons. Successful NEP space vehicle development is going to bring practical space exploration of solar system to the new level as well as require supplementary payload program, supporting monitoring and communication radar networks. Nuclear safety during future NEP missions can be ensured by adherence to the United Nations guidelines in the same way it was done during the Soviet Topaz Nuclear Power System (NPS) missions.

  9. Lightweight Radiator for in Space Nuclear Electric Propulsion

    Science.gov (United States)

    Craven, Paul; Tomboulian, Briana; SanSoucie, Michael

    2014-01-01

    Nuclear electric propulsion (NEP) is a promising option for high-speed in-space travel due to the high energy density of nuclear fission power sources and efficient electric thrusters. Advanced power conversion technologies may require high operating temperatures and would benefit from lightweight radiator materials. Radiator performance dictates power output for nuclear electric propulsion systems. Game-changing propulsion systems are often enabled by novel designs using advanced materials. Pitch-based carbon fiber materials have the potential to offer significant improvements in operating temperature, thermal conductivity, and mass. These properties combine to allow advances in operational efficiency and high temperature feasibility. An effort at the NASA Marshall Space Flight Center to show that woven high thermal conductivity carbon fiber mats can be used to replace standard metal and composite radiator fins to dissipate waste heat from NEP systems is ongoing. The goals of this effort are to demonstrate a proof of concept, to show that a significant improvement of specific power (power/mass) can be achieved, and to develop a thermal model with predictive capabilities making use of constrained input parameter space. A description of this effort is presented.

  10. The nuclear electricity generating industry in England and Wales post-privatisation

    International Nuclear Information System (INIS)

    Johnson, C.B.

    1992-01-01

    This paper presents an overview of the new legal framework within which the nuclear generating industry has operated in England and Wales since 31 March 1990. It describes the formation of Nuclear Electric plc and the licensing arrangements, including the various obligations which have been placed upon Nuclear Electric by virtue of its Generation Licence. The impact of competition law is outlined, together with the commercial arrangements including electricity pooling and some of the other more important agreements which Nuclear Electric has entered into. Finally, the Paper discusses some of the constraints under which Nuclear Electric operates, and summarises Government policy towards nuclear power and its future prospects in the United Kingdom. (author)

  11. Systems integration processes for space nuclear electric propulsion systems

    International Nuclear Information System (INIS)

    Olsen, C.S.; Rice, J.W.; Stanley, M.L.

    1991-01-01

    The various components and subsystems that comprise a nuclear electric propulsion system should be developed and integrated so that each functions ideally and so that each is properly integrated with the other components and subsystems in the optimum way. This paper discusses how processes similar to those used in the development and intergration of the subsystems that comprise the Multimegawatt Space Nuclear Power System concepts can be and are being efficiently and effectively utilized for these purposes. The processes discussed include the development of functional and operational requirements at the system and subsystem level; the assessment of individual nuclear power supply and thruster concepts and their associated technologies; the conduct of systems integration efforts including the evaluation of the mission benefits for each system; the identification and resolution of concepts development, technology development, and systems integration feasibility issues; subsystem, system, and technology development and integration; and ground and flight subsystem and integrated system testing

  12. Study of reactor Brayton power systems for nuclear electric spacecraft

    Science.gov (United States)

    1979-01-01

    The feasibility of using Brayton power systems for nuclear electric spacecraft was investigated. The primary performance parameters of systems mass and radiator area were determined for systems from 100 to 1000 kW sub e. Mathematical models of all system components were used to determine masses and volumes. Two completely independent systems provide propulsion power so that no single-point failure can jeopardize a mission. The waste heat radiators utilize armored heat pipes to limit meteorite puncture. The armor thickness was statistically determined to achieve the required probability of survival. A 400 kW sub e reference system received primary attention as required by the contract. The components of this system were defined and a conceptual layout was developed with encouraging results. An arrangement with redundant Brayton power systems having a 1500 K (2240 F) turbine inlet temperature was shown to be compatible with the dimensions of the space shuttle orbiter payload bay.

  13. Nuclear electric propulsion operational reliability and crew safety study

    International Nuclear Information System (INIS)

    Karns, J.J.; Fragola, J.R.; Kahan, L.; Pelaccio, D.

    1993-01-01

    The central purpose of this analysis is to assess the ''achievability'' of a nuclear electric propulsion (NEP) system in a given mission. ''Achievability'' is a concept introduced to indicate the extent to which a system that meets or achieves its design goals might be implemented using the existing technology base. In the context of this analysis, the objective is to assess the achievability of an NEP system for a manned Mars mission as it pertains to operational reliability and crew safety goals. By varying design parameters, then examining the resulting system achievability, the design and mission risk drivers can be identified. Additionally, conceptual changes in design approach or mission strategy which are likely to improve overall achievability of the NEP system can be examined

  14. Review of existing studies and unresolved problems associated with socio-economic impact of nuclear powerplants

    International Nuclear Information System (INIS)

    Hendrickson, P.L.; King, J.C.; O'Connell, M.S.

    1975-07-01

    Preparation of socio-economic impact statements for nuclear powerplants began only a few years ago. The number of these statements is increasing, and some states, such as Washington, now require them as a condition to state approval for thermal powerplants. The major purpose of this paper was to review existing socio-economic impact statements to identify where additional research to improve the impact analysis process would be useful and appropriate. A second purpose was to summarize the type of information included in existing statements. Toward this end a number of socio-economic impact statements were reviewed. Most of the statements are for nuclear power plants; however, some are for other large construction projects. The statements reviewed are largely predictive in nature; i.e., they attempt to predict socio-economic impacts based on the existing knowledge. A few of the reports contain retroactive case studies of plants already completed. One describes an ongoing monitoring analysis of plants under construction. As a result of this preliminary study, a need was identified for a better-defined impact statement methodology and for guidelines identifying appropriate areas for analysis and analytical techniques

  15. The development of direct core monitoring in Nuclear Electric plc

    International Nuclear Information System (INIS)

    Curtis, R.F.; Jones, S. Reed, J.; Wickham, A.J.

    1996-01-01

    Monitoring of graphite behaviour in Nuclear Electric Magnox and AGR reactors is necessary to support operating safety cases and to ensure that reactor operation is optimized to sustain the necessary core integrity for the economic life of the reactors. The monitoring programme combines studies for pre-characterized ''installed'' samples with studies on samples trepanned from within the cores and also with studies of core and channel geometry using specially designed equipment. Nuclear Electric has two trepanning machines originally designed for Magnox-reactor work which have been used for a substantial programme over many years. They have recently been upgraded to improve sampling speed, safety and versatility - the last being demonstrated by their adaptation for a recently-won contract associated with decommissioning the Windscale piles. Radiological hazards perceived when the AGR trepanning system was designed resulted in very cumbersome equipment. This has worked well but has been inconvenient in operation. The development of a smaller and improved system for deploying the equipment is now reported. Channel dimension monitoring equipment is discussed in detail with examples of data recovered from both Magnox and AGR cores. A resolution of ± 2 of arc (tilt) and ± 0.01 mm change in diameter in attainable. It is also theoretically possible to establish brick stresses by measuring geometry changes which result from trepanning. Current development work on a revolving scanning laser rangefinder which will enable the measurement of diameters to a resolution of 0.001 mm will also be discussed. This paper also discusses non-destructive techniques for crack detection employing ultrasound or resistance networks, the use of special manipulators to deliver inspection and repair equipment and recent developments to install displacement monitors in peripheral regions of the cores, to aid the understanding of the interaction of the restraint system with the core - the region

  16. Powerplant construction: the 20-year outlook

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    A summary of a report on Capital costs of projected power plants in the USA is provided. 125,000 MW of plant is under construction representing 100 billion dollars of investment. Twenty-seven large nuclear plants account for most of the investment and 34% (24 plants) are coal-fired. The capital costs of the power plants are surveyed

  17. Factors affecting the cost and competitiveness of nuclear electricity

    International Nuclear Information System (INIS)

    Bertel, E.; Stevens, G.H.

    1996-01-01

    The general context in which are carried out the investment choices of the electric sector has evolved in a significant way during these last years and the changes are to a certain extent irreversible. Economic globalization, deregulation of the electricity market, privatisation of electricity producers, and increasing awareness of environmental issues are modifying the policy-making landscape and the criteria and priorities of decision-makers in the power sector. Competitiveness remains a cornerstone for evaluating and choosing alternative technologies in the process of planning and decision-making for electricity system expansion or power plant replacement. Nevertheless, the production costs analysis inserts factors which were not taking before into account as for instance social impacts, health and environmental effects. These new approaches better reveal the total costs of the different production means. They will certainly lead to different choices than those based on the whole comparison of direct costs supported by producers. The economic studies carried out by the Nuclear Energy Agency of the OECD (NEA) cover all the preceding aspects and give objective information on the competitiveness of nuclear electricity. The nuclear industry has today the necessary means to take up the challenges of the electricity new markets. (O.M.)

  18. Radioactive waste management at nuclear electric power stations

    International Nuclear Information System (INIS)

    Gordelier, S.C.

    1993-01-01

    After suitable treatment, gaseous and liquid wastes are routinely discharged from Nuclear Electric's stations and are diluted and dispersed in the environment. The discharges are controlled and authorized under UK legislation and the environmental impact is minimal. Most solid wastes were originally accumulated at the site of origin, but since 1978 low level wastes (LLW) have been send to the UK's main disposal site at Drigg. Recent changes at Drigg have resulted in changed arrangements for the transport and disposal of low-level wastes, including volume reduction by supercompaction. Small amounts of intermediate-level waste (ILW) have been conditioned and disposed of in the sea but this route is now effectively closed and there is currently no disposal route for ILW in the UK. Spent ion exchange resins at one power station have been conditioned and are stored pending the availability of a disposal route. Most ILW will continue to be stored in retrievable form on the site of origin until a mobile waste treatment plant can be brought into use. The timing of this will be subject to agreement with the regulators. In the case of Magnox fuel element debris, a demonstration dissolution plant has been constructed and this will significantly reduce the volume of waste being stored while retaining the bulk of the activity on site for later treatment. A further development has been the construction of a new facility which will hold Magnox fuel element debris in 500 liter drums

  19. Parametric utility comparison of coal and nuclear electricity generation

    International Nuclear Information System (INIS)

    Maurer, K.M.

    1977-02-01

    The advantages and limitations of an explicit quantitative model for decision making are discussed. Several different quantitative models are presented, noting that the use of an expected utility maximization decision rule allows both the direct incorporation of multidimensional descriptions of the possible outcomes, and considerations of risk averse behavior. A broad class of utility functions, characterized by linear risk tolerance, was considered and extended to a multidimensional form. Choosing a multivariate risk neutral extension, using constant absolute risk aversion utility functions for monetary effects and for increased mortality, the author indicated how the parameters of this utility function can be selected to represent the decision maker's preferences, and suggest a reasonable range of values for the parameters. After describing an illustrative set of data on the risks inherent in coal burning and nuclear electricity generation facilities, the author used the chosen utility model to compare the overall risks associated with each technology, observing the effect of variations in the utility parameters and in the risk distributions on the implied preferences

  20. Effects of emission reductions at the Hayden powerplant on precipitation, snowpack, and surface-water chemistry in the Mount Zirkel Wilderness Area, Colorado, 1995-2003

    Science.gov (United States)

    Mast, M. Alisa; Campbell, Donald H.; Ingersoll, George P.

    2005-01-01

    Precipitation, snowpack, and surface-water samples collected during 1995-2003 were analyzed to evaluate the effects of emission reductions at the Hayden powerplant on water chemistry in the Mount Zirkel Wilderness Area. The Hayden powerplant, one of two large coal-fired powerplants in the Yampa Valley, was retrofitted with control systems during late 1998 and 1999 to reduce emissions of sulfur dioxide and nitrogen oxide--the primary precursors of haze and acidic precipitation. The U.S. Geological Survey, in cooperation with the Colorado Department of Public Health and Environment, evaluated three water-chemistry data sets: wet-only precipitation chemistry from the National Atmospheric Deposition Program, snowpack chemistry from the Rocky Mountain snowpack network, and surface-water chemistry from a U.S. Geological Survey long-term lakes monitoring program. Concentrations and deposition rates of selected constituents were compared for the periods before and after emission reductions at the Hayden powerplant. Data collected during 1995-98 were used to represent the pre-control period, and data collected during 2000-2003 were used to represent the post-control period. Ten stations in the National Atmospheric Deposition Program were evaluated including two that were directly downwind from the Hayden powerplant (Dry Lake and Buffalo Pass) and eight that were upwind or more distant (more than 100 kilometers) from the powerplant. Precipitation amount at all 10 precipitation stations was lower in the post-control period than the pre-control period as a result of a regional drought that persisted during the post-control period. In contrast to precipitation amount, there was no consistent pattern of change in sulfate concentrations between periods, indicating that the drought did not have a concentrating effect on sulfate or that trends in regional sulfur dioxide emissions masked its influence. Sulfate concentrations increased at three stations between periods, remained the

  1. Concept for a shuttle-tended reusable interplanetary transport vehicle using nuclear electric propulsion

    Science.gov (United States)

    Nakagawa, R. Y.; Elliot, J. C.; Spilker, T. R.; Grayson, C. M.

    2003-01-01

    NASA has placed new emphasis on the development of advanced propulsion technologies including Nuclear Electric Propulsion (NEP). This technology would provide multiple benefits including high delta-V capability and high power for long duration spacecraft operations.

  2. Development of a spatial nuclear electric system: RESPA sub-project

    International Nuclear Information System (INIS)

    Ishiguro, Y.

    1989-04-01

    Basic design and characteristics of a nuclear-electric system selected for future applications in the Brazilian space program is summarized. Technological difficulties are discussed and a preliminary program of research and development at IEAv is presented. (author)

  3. Dr. von Braun and Dr. Stuhlinger With a Model of the Nuclear-Electric Vehicles

    Science.gov (United States)

    2004-01-01

    In this photo, taken at the Walt Disney Studios in California, Dr. Wernher von Braun and Dr. Ernst Stuhlinger are shown discussing the concepts of nuclear-electric spaceships designed to undertake the mission to the planet Mars. As a part of the Disney 'Tomorrowland' series on the exploration of space, the nuclear-electric vehicles were shown in the last three television films, entitled 'Mars and Beyond,' which first aired in December 1957.

  4. Assessing inundation hazards to nuclear powerplant sites using geologically extended histories of riverine floods, tsunamis, and storm surges

    Science.gov (United States)

    O'Connor, Jim; Atwater, Brian F.; Cohn, Timothy A.; Cronin, Thomas M.; Keith, Mackenzie K.; Smith, Christopher G.; Mason, Jr., Robert R.

    2014-01-01

    Most nuclear powerplants in the United States are near rivers, large lakes, or oceans. As evident from the Fukushima Daiichi, Japan, disaster of 2011, these water bodies pose inundation threats. Geologic records can extend knowledge of rare hazards from flooding, storm surges, and tsunamis. This knowledge can aid in assessing the safety of critical structures such as dams and energy plants, for which even remotely possible hazards are pertinent. Quantitative analysis of inundation from geologic records perhaps is most developed for and applied to riverine flood hazards, but because of recent natural disasters, geologic investigations also are now used widely for understanding tsunami hazards and coastal storm surges.

  5. Professor Jeffery on the real cost of nuclear electricity in the UK: a note; and reply

    International Nuclear Information System (INIS)

    McGuire, A.; Barclay, R.S.; Jeffery, J.W.

    1982-01-01

    Two letters published in reply to an earlier article on the real cost of nuclear electricity in the U.K. criticize the use of the Retail Price Index as a price deflator and the attempts to convert capital charges from historical to a current cost basis. Corrections are made to the corresponding results. The author of the original article replies. (U.K.)

  6. Strategies and tactics of the negotiation for powerplant siting

    International Nuclear Information System (INIS)

    Wakatani, Yoshifumi; Yamanaka, Yoshiro; Yamamoto, Kimio

    1983-01-01

    Recently, the negotiation with local inhabitants in powerplant siting area is apt to drag on and is becoming more intricate. The purpose of this study is to present strategies and tactics for stepping up the negotiation more smoothly, taking the case of the negotiation with a fishermen's union. In this report, a case study is made for ten cases regarding negotiation with local fishermen's unions in order to find out how the negotiations were carried out. The results of the study are summarized as follows. 1) The negotiations were classified into four types in accordance with the characteristics of each case (e.g. historical background, type of project). 2) An analysis was made about the relationship between the degree of difficulty of negotiation (e.g. period of time of the negotiation for fishery compensation) and the characteristics of the case. As a result, it was found that the degree of difficulty of negotiation has a close relationship to the historical background and the fishery productivity. 3) Persons concerned with the negotiation were classified into three groups. The interested party, the mediators and the supporters, according to the relationship among these persons and the roles played by them. 4) External events haveing an effect on the development of the negotiation were extracted and pigeonholed. 5) The behavior of the persons concerned was analyzed and thirty-eight measures were figured out which were considered to be effective to negotiate smoothly. (author)

  7. Economic prospective study of the nuclear electricity generation sector

    International Nuclear Information System (INIS)

    Pellat, R.; Charpin, J.M.; Dessus, B.

    2000-01-01

    In his letter dated May 7. 1999, the French Prime Minister Lionel Jospin asked Jean-Michel Charpin, Benjamin Dessus and Rene Pellat to carry out a 'study of the economic data for the whole of the nuclear sector, in particular downstream of the nuclear combustion cycle, including reprocessing'. This report had to include comparisons with other production methods for electricity and take account of environmental costs. The Prime Minister stressed in this same letter his wish to see the inquiry 'examine all of the factors forming the basis for a public decision, including intrinsic competitiveness, external factors and long-term effects, as well as the impact of different production methods upon our CO 2 gas emissions and control over the downstream part of the nuclear cycle'. Two series of questions are central to this study. The first concerns the existing nuclear facilities. In view of the inertia of a French electrical production system which is largely based upon nuclear energy and in which major investments have already been made, what room for manoeuvre remains for the public authorities and operators concerning the future of these stations? In particular: What are the economic conditions and consequences of possibly prolonging the average active life of the existing stations? What are the economic and environmental consequences of decisions concerning the continuation or stoppage of the reprocessing of irradiated fuel produced by the existing stations? The second concerns new investments likely to meet electrical demand under various scenarios. In particular: what are the technologies that may be envisaged (nuclear and non-nuclear) and in what timescale? What are the changes underway in the world that are likely to have an influence on the choices made in France? What will be the environmental consequences of these choices by the year 2050, in particular regarding greenhouse gas emissions and the quantities of transuranic elements to be stored? What will be

  8. Los Alamos Nuclear Plant Analyzer: an interactive power-plant simulation program

    International Nuclear Information System (INIS)

    Steinke, R.; Booker, C.; Giguere, P.; Liles, D.R.; Mahaffy, J.H.; Turner, M.R.

    1984-01-01

    The Nuclear Plant Analyzer (NPA) is a computer-software interface for executing the TRAC or RELAP5 power-plant systems codes. The NPA is designed to use advanced supercomputers, long-distance data communications, and a remote workstation terminal with interactive computer graphics to analyze power-plant thermal-hydraulic behavior. The NPA interface simplifies the running of these codes through automated procedures and dialog interaction. User understanding of simulated-plant behavior is enhanced through graphics displays of calculational results. These results are displayed concurrently with the calculation. The user has the capability to override the plant's modeled control system with hardware-adjustment commands. This gives the NPA the utility of a simulator, and at the same time, the accuracy of an advanced, best-estimate, power-plant systems code for plant operation and safety analysis

  9. Nuclear Plant Analyzer: an interactive TRAC/RELAP Power-Plant Simulation Program

    International Nuclear Information System (INIS)

    Steinke, R.; Booker, C.; Giguere, P.; Liles, D.; Mahaffy, J.; Turner, M.; Wiley, R.

    1984-01-01

    The Nuclear Plant Analyzer (NPA) is a computer-software interface for executing the TRAC or RELAP5 power-plant systems codes. The NPA is designed to use advanced supercomputers, long-distance data communications, and a remote workstation terminal with interactive computer graphics to analyze power-plant thermal-hydraulic behavior. The NPA interface simplifies the running of these codes through automated procedures and dialog interaction. User understanding of simulated-plant behavior is enhanced through graphics displays of calculational results. These results are displayed concurrently with the calculation. The user has the capability to override the plant's modeled control system with hardware adjustment commands. This gives the NPA the utility of a simulator, and at the same time, the accuracy of an advanced, best-estimate, power-plant systems code for plant operation and safety analysis

  10. Conceptual design study of a coal gasification combined-cycle powerplant for industrial cogeneration

    Science.gov (United States)

    Bloomfield, H. S.; Nelson, S. G.; Straight, H. F.; Subramaniam, T. K.; Winklepleck, R. G.

    1981-01-01

    A conceptual design study was conducted to assess technical feasibility, environmental characteristics, and economics of coal gasification. The feasibility of a coal gasification combined cycle cogeneration powerplant was examined in response to energy needs and to national policy aimed at decreasing dependence on oil and natural gas. The powerplant provides the steam heating and baseload electrical requirements while serving as a prototype for industrial cogeneration and a modular building block for utility applications. The following topics are discussed: (1) screening of candidate gasification, sulfur removal and power conversion components; (2) definition of a reference system; (3) quantification of plant emissions and waste streams; (4) estimates of capital and operating costs; and (5) a procurement and construction schedule. It is concluded that the proposed powerplant is technically feasible and environmentally superior.

  11. Nuclear Electric: the misuse of the subsidy and the case for the immediate closure of Magnox

    International Nuclear Information System (INIS)

    1992-11-01

    The nature and purpose of fossil fuel levy which creates a subsidy for the nuclear industry is discussed. It is claimed that without the subsidy the operation of Magnox and AGR stations generates electricity at a loss. This means that most of the fossil fuel levy is being used to make up Nuclear Electric's losses. The rest is mostly being used to build the Sizewell-B power plant. This is in contrast to the popular belief and understanding that the subsidy is for decommissioning old plants, and cleaning up accumulated spent fuels and other wastes. The economics of the Magnox stations are discussed and Nuclear Electric's claim that closing them would not stop the losses is challenged. (U.K.)

  12. Speeding up the construction of nuclear electricity in accordance with the practice of China

    International Nuclear Information System (INIS)

    Zhang Wenqing; Chen Shuyun

    1986-01-01

    In order to fulfil the developing plan of national economy in China, the lasting and stable energy resources are needed. According to the tendency and present status of developing nuclear electricity in the world and the conditions in China, this paper has expounded that while the coal-fired and hydroelectric power plants are being developed actively, the nuclear power plants should be built step by step. At present importance must be attached to build medium and small sized nuclear power stations

  13. Radioactive liquid waste discharged from Nuclear Electric licensed sites during 1991

    International Nuclear Information System (INIS)

    Austin, L.S.; Odell, K.J.

    1993-03-01

    This report presents the detailed isotopic composition of radioactive liquid waste discharged from Nuclear Electric licensed sites in 1991. Liquid discharges from those Magnox stations using pond storage of irradiated fuel contained low levels of activation and fission products, while those from Wylfa and the AGR stations contained lower levels of activation products with only traces of fission products. Discharges were similar to those observed in previous years, with any changes concordant with changes in stations' generation performance. (author)

  14. Nuclear electricity in the U.S.A. - A status report

    Energy Technology Data Exchange (ETDEWEB)

    Loewenstein, W B [American Nuclear Society, Hinsdale, IL (United States)

    1990-06-01

    The status of nuclear electricity programs in the USA is reviewed. About 20% of the electricity in the USA comes from nuclear generating stations. The potential impact of greenhouse concerns is prominent in plans for the future. Advanced reactor programs for water, liquid metal and gas cooled systems is reviewed. Safety and plant economics feature prominently in future considerations. The increasing average availability of nuclear stations in the USA provides some insights on lessons to be learned for the future. (author)

  15. Nuclear electricity in the U.S.A. - A status report

    International Nuclear Information System (INIS)

    Loewenstein, W.B.

    1990-01-01

    The status of nuclear electricity programs in the USA is reviewed. About 20% of the electricity in the USA comes from nuclear generating stations. The potential impact of greenhouse concerns is prominent in plans for the future. Advanced reactor programs for water, liquid metal and gas cooled systems is reviewed. Safety and plant economics feature prominently in future considerations. The increasing average availability of nuclear stations in the USA provides some insights on lessons to be learned for the future. (author)

  16. Report and recommendations of the Brilliant powerplant expansion project committee

    International Nuclear Information System (INIS)

    2001-01-01

    An application was submitted in December 2000 for a project approval certificate for the Brilliant Powerplant Expansion Project (BEP). It included the construction and operation of a new powerhouse with a generating capacity of close to 100 MW, a new intake and tailrace channels, as well as tailrace channel improvements, a powerhouse access bridge over the Kootenay River downstream from the Brilliant Dam, a 600 metre 230 kV transmission link and 230 kV switchyard (the switchyard is no longer part of the project), a construction site and excavation materials disposal areas, and access to the site from Highway 3A and also from Robson Road. Both before and during the environmental assessment review, comprehensive public consultation was undertaken. The issues that were examined were environmental effects, operations, socio-economic effects, health effects, and the cultural and heritage effects. It was concluded that the effects issues related to the construction of the project had been resolved, based on the information provided in the Application and on the mitigation and compensation measures. The potential impact on fish and fish habitat were examined under the operations heading. Again, the committee determined that the proponent had committed to target minimum flows and restrictions, and that the effects issues associated with the operations of the project had been resolved. Increased traffic through the community of Brilliant represented the main focus of the evaluation of the socio-economic effects. Positive economic and employment effects on local communities were expected, and the proponent was ready to address any potential negative social effects to the satisfaction of the committee. Groundwater resources were the only potentially significant effect identified under the heading health effects, and adequate compensation and mitigation measures were committed by the proponent to address the issue. The cultural and heritage effects identified archaeological

  17. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle

    The capability to perform fast load changes has been an important issue in the power market, and will become increasingly more so due to the incresing commercialisation of the European power market. An optimizing control system for improving the load-following capability of power-plant units has...... tests on a 265 MW coal-fired power-plant unit reveals that the maximum allowable load gradient that can be imposed on the plant, can be increased from 4 MW/min. to 8 MW/min....

  18. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle

    1998-01-01

    The capability to perform fast load changes has been an important issue in the power market, and will become increasingly more so due to the incresing commercialisation of the European power market. An optimizing control system for improving the load-following capability of power-plant units has...... tests on a 265 MW coal-fired power-plant unit reveals that the maximum allowable load gradient that can be imposed on the plant, can be increased from 4 MW/min. to 8 MW/min....

  19. Proton-Exchange-Membrane Fuel Cell Powerplants Developed and Tested for Exploration Missions

    Science.gov (United States)

    Hoberecht, Mark A.; Pham, Nang T.

    2005-01-01

    Proton-exchange-membrane fuel cell (PEMFC) technology has received major attention for terrestrial applications, such as the automotive and residential markets, for the past 20 years. This attention has significantly advanced the maturity of the technology, resulting in ever more compact, efficient, reliable, and inexpensive PEMFC designs. In comparison to the terrestrial operating environment, the space operating environment is much more demanding. Microgravity to high-gravity loads and the need to use pure oxygen (rather than air) as the fuel cell oxidizer place more stringent demands on PEMFC technology. NASA and its partners from industry are leveraging terrestrial PEMFC advancements by conducting parallel space technology development for future exploration missions. A team from the NASA Glenn Research Center, NASA Johnson Space Center, and NASA Kennedy Space Center recently completed the first phase of a PEMFC powerplant development effort for exploration missions. The industry partners for this phase of the development effort were ElectroChem, Inc., and Teledyne Energy Systems, Inc. Under contract to Glenn, both of these industry partners successfully designed, fabricated, and tested a breadboard PEMFC powerplant in the 1- to 5-kW power range. These powerplants were based on existing company-proprietary fuel cell stack designs, combined with off-the-shelf components, which formed the balance of the powerplant design. Subsequent to the contractor development efforts, both powerplants were independently tested at Johnson to verify operational and performance characteristics, and to determine suitability for further technology development in the second phase of the NASA-led effort. Following the independent NASA testing, Teledyne Energy Systems, Inc., was selected to develop an engineering model PEMFC powerplant. This effort was initiated by the 2nd Generation Reusable Launch Vehicle (RLV) Program Office in 2001; it transitioned to the Next Generation Launch

  20. Proton-Exchange-Membrane Fuel Cell Powerplants Developed and Tested for Exploration Missions

    Science.gov (United States)

    Hoberecht, Mark A.; Pham, Nang T.

    2005-06-01

    Proton-exchange-membrane fuel cell (PEMFC) technology has received major attention for terrestrial applications, such as the automotive and residential markets, for the past 20 years. This attention has significantly advanced the maturity of the technology, resulting in ever more compact, efficient, reliable, and inexpensive PEMFC designs. In comparison to the terrestrial operating environment, the space operating environment is much more demanding. Microgravity to high-gravity loads and the need to use pure oxygen (rather than air) as the fuel cell oxidizer place more stringent demands on PEMFC technology. NASA and its partners from industry are leveraging terrestrial PEMFC advancements by conducting parallel space technology development for future exploration missions. A team from the NASA Glenn Research Center, NASA Johnson Space Center, and NASA Kennedy Space Center recently completed the first phase of a PEMFC powerplant development effort for exploration missions. The industry partners for this phase of the development effort were ElectroChem, Inc., and Teledyne Energy Systems, Inc. Under contract to Glenn, both of these industry partners successfully designed, fabricated, and tested a breadboard PEMFC powerplant in the 1- to 5-kW power range. These powerplants were based on existing company-proprietary fuel cell stack designs, combined with off-the-shelf components, which formed the balance of the powerplant design. Subsequent to the contractor development efforts, both powerplants were independently tested at Johnson to verify operational and performance characteristics, and to determine suitability for further technology development in the second phase of the NASA-led effort. Following the independent NASA testing, Teledyne Energy Systems, Inc., was selected to develop an engineering model PEMFC powerplant. This effort was initiated by the 2nd Generation Reusable Launch Vehicle (RLV) Program Office in 2001; it transitioned to the Next Generation Launch

  1. Nuclear electric propulsion: A better, safer, cheaper transportation system for human exploration of Mars

    International Nuclear Information System (INIS)

    Clark, J.S.; George, J.A.; Gefert, L.P.; Doherty, M.P.; Sefcik, R.J.

    1994-03-01

    NASA has completed a preliminary mission and systems study of nuclear electric propulsion (NEP) systems for 'split-sprint' human exploration and related robotic cargo missions to Mars. This paper describes the study, the mission architecture selected, the NEP system and technology development needs, proposed development schedules, and estimated development costs. Since current administration policy makers have delayed funding for key technology development activities that could make Mars exploration missions a reality in the near future, NASA will have time to evaluate various alternate mission options, and it appears prudent to ensure that Mars mission plans focus on astronaut and mission safety, while reducing costs to acceptable levels. The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with 'reference' mission architectures. Thus, NEP systems offer short transit times for the astronauts, reducing the exposure of the crew to intergalactic cosmic radiation. The high specific impulse of the NEP system, which leads to very low propellant requirements, results in significantly lower 'initial mass in low earth orbit' (IMLEO). Launch vehicle packaging studies show that the NEP system can be launched, assembled, and deployed, with about one less 240-metric-ton heavy lift launch vehicle (HLLV) per mission opportunity - a very Technology development cost of the nuclear reactor for an NEP system would be shared with the proposed nuclear surface power systems, since nuclear systems will be required to provide substantial electrical power on the surface of Mars. The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw(e)) technology that has been developed for lunar and Mars surface nuclear power

  2. Nuclear Electric flask design and safety case development during the last ten years

    International Nuclear Information System (INIS)

    Dougall, I.; Jones, D.K.

    1994-01-01

    The scope of Nuclear Electric's (NE) requirements for irradiated fuel transport and the relevant safety and regulatory compliance standards are outlined. To illustrate NE's approach to demonstrating package design compliance the basis of the safety case for unbottled Magnox fuel transport in the Mk M2 Magnox flask is described. The considerations which lay behind the development of the Mk A2 AGR Flask are indicated and a description is given of the main design features of this flask. Finally there is a summary of progress in obtaining Type B(M) approvals, based on the 1985 IAEA Regulations, for the requisite range of flask contents. (author)

  3. A strategy for an advanced nuclear-electric sector - proliferation-proof, environmentally-sound, economical

    International Nuclear Information System (INIS)

    Walter, C.E.

    1995-01-01

    A strategy is proposed for deployment of an advanced nuclear-electric power sector that is ultimately fueled only by recycled uranium. The sector is optimized on a system basis to meet several objectives in the context of international safeguards against diversion of plutonium and proliferation of nuclear weapons. These objectives include: generation of electric power efficiently and economically; performance with utmost predictable safety; minimization of environmental impacts through conservation of natural resources, consumption of actinides and long-lived fission products, and responsible disposal of unavoidable waste; and consumption of spent fuel from currently used reactors. (author)

  4. The influence of Goiania radiological accident on Brazilian public opinion concerning new nuclear electric plants

    International Nuclear Information System (INIS)

    Meldonian, Nelson Leon; Mattos, Luis Antonio Terribile de

    1997-01-01

    The Brazilian society is against applications of nuclear energy, mainly respecting to construction of new nuclear power plants, believing that they are harmful to population's welfare and the environment. By this reason, Brazilian nuclear sector would promote a more intensive program of public discussion, not limited to technical and scientific community. Intending to contribute to a better judgment by society about the differences between diverse employment of nuclear energy, arguments concerned to its benefits are presented, pointing out that adverse accounts to nuclear electricity based on Goiania radiological accident, are not justified

  5. Nuclear electric propulsion for planetary science missions: NASA technology program planning

    International Nuclear Information System (INIS)

    Doherty, M.P.

    1993-01-01

    This paper presents the status of technology program planning to achieve readiness of Nuclear Electric Propulsion technologies needed to meet the advanced propulsion system requirements for planetary science missions in the next century. The technology program planning is based upon technologies of significant maturity: ion electric propulsion and the SP-100 space nulcear power technologies. Detailed plans are presented herein for the required ion electric propulsion technology development and demonstration. Closer coordination between space nuclear power and space electric propulsion technology programs is a necessity as technology plans are being further refined in light of NEP concept definition and possible early NEP flight activities

  6. Nuclear electric propulsion for planetary science missions: NASA technology program planning

    International Nuclear Information System (INIS)

    Doherty, M.P.

    1993-05-01

    This paper presents the status of technology program planning to develop those Nuclear Electric Propulsion technologies needed to meet the advanced propulsion system requirements for planetary science missions in the next century. The technology program planning is based upon technologies with significant development heritage: ion electric propulsion and the SP-100 space nuclear power technologies. Detailed plans are presented for the required ion electric propulsion technology development and demonstration. Closer coordination between space nuclear power and space electric propulsion technology programs is a necessity as technology plans are being further refined in light of NEP concept definition and possible early NEP flight activities

  7. Space nuclear power system and the design of the nuclear electric propulsion OTV

    International Nuclear Information System (INIS)

    Buden, D.; Garrison, P.W.

    1984-01-01

    Payload increases of three to five times that of the Shuttle/Centaur can be achieved using nuclear electric propulsion. Various nuclear power plant options being pursued by the SP-100 Program are described. These concepts can grow from 100 kW/sub e/ to 1MW/sub e/ output. Spacecraft design aspects are addressed, including thermal interactions, plume interactions, and radiation fluences. A baseline configuration is described accounting for these issues. Safety aspects of starting the OTV transfer from an altitude of 300 km indicate no significant additional risk to the biosphere

  8. Comparison of nuclear electric resonance and nuclear magnetic resonance in integer and fractional quantum Hall states

    International Nuclear Information System (INIS)

    Tomimatsu, Toru; Shirai, Shota; Hashimoto, Katsushi; Sato, Ken; Hirayama, Yoshiro

    2015-01-01

    Electric-field-induced nuclear resonance (NER: nuclear electric resonance) involving quantum Hall states (QHSs) was studied at various filling factors by exploiting changes in nuclear spins polarized at quantum Hall breakdown. Distinct from the magnetic dipole interaction in nuclear magnetic resonance, the interaction of the electric-field gradient with the electric quadrupole moment plays the dominant role in the NER mechanism. The magnitude of the NER signal strongly depends on whether electronic states are localized or extended. This indicates that NER is sensitive to the screening capability of the electric field associated with QHSs

  9. An effect of nuclear electric quadrupole moments in thermonuclear fusion plasmas

    Science.gov (United States)

    De, B. R.; Srnka, L. J.

    1978-01-01

    Consideration of the nuclear electric quadrupole terms in the expression for the fusion Coulomb barrier suggests that this electrostatic barrier may be substantially modified from that calculated under the usual plasma assumption that the nuclei are electric monopoles. This effect is a result of the nonspherical potential shape and the spatial quantization of the nuclear spins of the fully stripped ions in the presence of a magnetic field. For monopole-quadrupole fuel cycles like p-B-11, the fusion cross-section may be substantially increased at low energies if the protons are injected at a small angle relative to the confining magnetic field.

  10. Nuclear electricity generation a sustainable energy resource for Romania along the next two decades

    International Nuclear Information System (INIS)

    Prodea, Iosif; Margeanu, Cristina Alice; Aioanei, Corina; Prisecaru, Ilie; Danila, Nicolae

    2008-01-01

    The main goal of the paper is to evaluate different electricity generation costs inside of the National Romanian energy sector along the next two decades. The IAEA -MESSAGE code (Model for Energy Supply Strategy Alternatives and their General Environmental Impacts) will be used to accomplish these assessments. Due to the natural gas crisis started at the beginning of 2006, Romania has adopted a courageous energy policy based on increasing nuclear electricity share. Since then, the second nuclear Unit was commissioned at Cernavoda in 2007 and the other two CANDU-6 (700 MWe) were scheduled to be operational in 2015. On the other side the European integration of Romania asks for doubling the indigenous gas price during this year, 2008, and also for reducing the atmospheric gaseous emissions from the fossil fuel technologies. Therefore, we evaluated the economical competition between all electricity technologies in the Romanian energy sector in the next two decades for which our MESSAGE model was developed. We focused on coal, gas and, of course, nuclear electricity technologies. Some representative energy scenarios centered on nuclear share electricity growing were considered and MESSAGE results were analyzed from the energetic sustainable point of view. (authors)

  11. Cold shock to aquatic organisms: guidance for power-plant siting, design, and operation

    International Nuclear Information System (INIS)

    Coutant, C.C.

    1977-01-01

    Problems of cold-shock damages to aquatic organisms have arisen at some condenser cooling-water discharges of thermal power stations when the warm-water releases have suddenly terminated. The basis for such damage lies in the exposure of resident organisms to a rapid decrease in temperature and a sustained exposure to low temperature that induces abnormal behavioral or physiological performance and often leads to death. Although some spectacular fish kills from cold shock have occurred, the present knowledge of the hydraulic and biological processes involved can provide guidance for the siting, design, and operation of power-plant cooling systems to minimize the likelihood of significant cold-shock effects. Preventing cold-shock damages is one consideration in minimizing overall environmental impacts of power-plant cooling and in balancing plant costs with environmental benefits

  12. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    OpenAIRE

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle; Pedersen, Tom Søndergaard

    1998-01-01

    The capability to perform fast load changes has been an important issue in the power market, and will become increasingly more so due to the incresing commercialisation of the European power market. An optimizing control system for improving the load-following capability of power-plant units has therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advanta...

  13. Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at Grand Coulee Dam Third Powerplant Forebay

    International Nuclear Information System (INIS)

    Simmons, Mary Ann; Johnson, Robert L.; McKinstry, Craig A.; Simmons, Carver S.; Cook, Chris B.; Brown, Richard S.; Tano, Daniel K.; Thorsten, Susan L.; Faber, Derrek M.; Lecaire, Richard; Francis, Stephen

    2004-01-01

    This report documents the third year of a four-year study to assess the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee salmon (Oncorhynchus nerka) and rainbow trout (O. mykiss) in the forebay to the third powerplant at Grand Coulee Dam. This work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by Pacific Northwest National Laboratory (PNNL) in conjunction with the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes)

  14. Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at Grand Coulee Dam Third Powerplant Forebay

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Mary Ann; Johnson, Robert L.; McKinstry, Craig A.; Simmons, Carver S.; Cook, Chris B.; Brown, Richard S.; Tano, Daniel K.; Thorsten, Susan L.; Faber, Derrek M.; Lecaire, Richard; Francis, Stephen

    2004-01-01

    This report documents the third year of a four-year study to assess the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee salmon (Oncorhynchus nerka) and rainbow trout (O. mykiss) in the forebay to the third powerplant at Grand Coulee Dam. This work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by Pacific Northwest National Laboratory (PNNL) in conjunction with the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes).

  15. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in COAL IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2004-09-30

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, has been re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for Coal IGCC powerplants. The new program has been re-titled as ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants'' to better match the new scope. This technical progress report summarizes the work accomplished in the reporting period April 1, 2004 to August 31, 2004 on the revised Re-Directed and De-Scoped program activity. The program Tasks are: Task 1--IGCC Environmental Impact on high Temperature Materials: This first materials task has been refocused to address Coal IGCC environmental impacts on high temperature materials use in gas turbines and remains in the program. This task will screen material performance and quantify the effects of high temperature erosion and corrosion of hot gas path materials in Coal IGCC applications. The materials of interest will include those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: This second task develops and demonstrates new sensor technologies to determine the in-service health of advanced technology Coal IGCC powerplants, and remains in the program with a reduced scope. Its focus is now on only two critical sensor need areas for advanced Coal IGCC gas turbines: (1) Fuel Quality Sensor for detection of fuel impurities that could lead to rapid component degradation, and a Fuel Heating Value Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware.

  16. A closed Brayton power conversion unit concept for nuclear electric propulsion for deep space missions

    International Nuclear Information System (INIS)

    Joyner, Claude Russell II; Fowler, Bruce; Matthews, John

    2003-01-01

    In space, whether in a stable satellite orbit around a planetary body or traveling as a deep space exploration craft, power is just as important as the propulsion. The need for power is especially important for in-space vehicles that use Electric Propulsion. Using nuclear power with electric propulsion has the potential to provide increased payload fractions and reduced mission times to the outer planets. One of the critical engineering and design aspects of nuclear electric propulsion at required mission optimized power levels is the mechanism that is used to convert the thermal energy of the reactor to electrical power. The use of closed Brayton cycles has been studied over the past 30 or years and shown to be the optimum approach for power requirements that range from ten to hundreds of kilowatts of power. It also has been found to be scalable to higher power levels. The Closed Brayton Cycle (CBC) engine power conversion unit (PCU) is the most flexible for a wide range of power conversion needs and uses state-of-the-art, demonstrated engineering approaches. It also is in use with many commercial power plants today. The long life requirements and need for uninterrupted operation for nuclear electric propulsion demands high reliability from a CBC engine. A CBC engine design for use with a Nuclear Electric Propulsion (NEP) system has been defined based on Pratt and Whitney's data from designing long-life turbo-machines such as the Space Shuttle turbopumps and military gas turbines and the use of proven integrated control/health management systems (EHMS). An integrated CBC and EHMS design that is focused on using low-risk and proven technologies will over come many of the life-related design issues. This paper will discuss the use of a CBC engine as the power conversion unit coupled to a gas-cooled nuclear reactor and the design trends relative to its use for powering electric thrusters in the 25 kWe to 100kWe power level

  17. Proton Exchange Membrane Fuel Cell Engineering Model Powerplant. Test Report: Benchmark Tests in Three Spatial Orientations

    Science.gov (United States)

    Loyselle, Patricia; Prokopius, Kevin

    2011-01-01

    Proton exchange membrane (PEM) fuel cell technology is the leading candidate to replace the aging alkaline fuel cell technology, currently used on the Shuttle, for future space missions. This test effort marks the final phase of a 5-yr development program that began under the Second Generation Reusable Launch Vehicle (RLV) Program, transitioned into the Next Generation Launch Technologies (NGLT) Program, and continued under Constellation Systems in the Exploration Technology Development Program. Initially, the engineering model (EM) powerplant was evaluated with respect to its performance as compared to acceptance tests carried out at the manufacturer. This was to determine the sensitivity of the powerplant performance to changes in test environment. In addition, a series of tests were performed with the powerplant in the original standard orientation. This report details the continuing EM benchmark test results in three spatial orientations as well as extended duration testing in the mission profile test. The results from these tests verify the applicability of PEM fuel cells for future NASA missions. The specifics of these different tests are described in the following sections.

  18. Technology for Bayton-cycle powerplants using solar and nuclear energy

    Science.gov (United States)

    English, R. E.

    1986-01-01

    Brayton cycle gas turbines have the potential to use either solar heat or nuclear reactors for generating from tens of kilowatts to tens of megawatts of power in space, all this from a single technology for the power generating system. Their development for solar energy dynamic power generation for the space station could be the first step in an evolution of such powerplants for a very wide range of applications. At the low power level of only 10 kWe, a power generating system has already demonstrated overall efficiency of 0.29 and operated 38 000 hr. Tests of improved components show that these components would raise that efficiency to 0.32, a value twice that demonstrated by any alternate concept. Because of this high efficiency, solar Brayton cycle power generators offer the potential to increase power per unit of solar collector area to levels exceeding four times that from photovoltaic powerplants using present technology for silicon solar cells. The technologies for solar mirrors and heat receivers are reviewed and assessed. This Brayton technology for solar powerplants is equally suitable for use with the nuclear reactors. The available long time creep data on the tantalum alloy ASTAR-811C show that such Brayton cycles can evolve to cycle peak temperatures of 1500 K (2240 F). And this same technology can be extended to generate 10 to 100 MW in space by exploiting existing technology for terrestrial gas turbines in the fields of both aircraft propulsion and stationary power generation.

  19. Decree No. 77-1233 of 10 November 1977 setting up a Council for information on nuclear electricity generation

    International Nuclear Information System (INIS)

    1977-01-01

    This Decree sets up a Council for information on nuclear electricity generation directly under the authority of and appointed by the Prime Minister. It has 18 members who include, inter alia, mayors of the communes concerned by nuclear power plant siting, representatives of nature and environmental protection associations, science academicians and economics, energy and communications experts. The Council's purpose is to ensure that the public has access to infomation on nuclear electricity generation from the technical, health, ecological, economic and financial viewpoints. It advises the Government on the public's conditions of access to information and proposes methods for its dissemination. (NEA) [fr

  20. Multi-reactor power system configurations for multimegawatt nuclear electric propulsion

    Science.gov (United States)

    George, Jeffrey A.

    1991-01-01

    A modular, multi-reactor power system and vehicle configuration for piloted nuclear electric propulsion (NEP) missions to Mars is presented. Such a design could provide enhanced system and mission reliability, allowing a comfortable safety margin for early manned flights, and would allow a range of piloted and cargo missions to be performed with a single power system design. Early use of common power modules for cargo missions would also provide progressive flight experience and validation of standardized systems for use in later piloted applications. System and mission analysis are presented to compare single and multi-reactor configurations for piloted Mars missions. A conceptual design for the Hydra modular multi-reactor NEP vehicle is presented.

  1. Hyperfine structure in the Gd II spectrum and the nuclear electric quadrupole moment of 157Gd

    International Nuclear Information System (INIS)

    Clieves, H.P.; Steudel, A.

    1979-01-01

    The hyperfine structure of 157 Gd was investigated in 20 Gd II lines by means of a photoelectric recording Fabry-Perot interferometer with digital data processing. The hyperfine splitting factors, A and B, were obtained by computer fits to the observed line structures. Using a multiconfigurational set of wave functions in intermediate coupling derived by Wyart, mono-electronic parameters were deduced by a parametric treatment. The nuclear electric quadrupole moment of 157 Gd was evaluated from the quadrupole interaction of the 5d electron in 4f 7 5d6s, the 5d electron in 4f 7 5d6p, and the 6p electron in 4f 7 5d6p. The three values obtained for the quadrupole moment agree very well. The final result, corrected for Sternheimer shielding, is Q( 157 Gd) = 1.34(7) x 10 -24 cm 2 . (orig.) [de

  2. Nuclear electric propulsion: An integral part of NASA's nuclear propulsion project

    International Nuclear Information System (INIS)

    Stone, J.R.

    1992-01-01

    NASA has initiated a technology program to establish the readiness of nuclear propulsion technology for the Space Exploration Initiative (SEI). This program was initiated with a very modest effort identified with nuclear thermal propulsion (NTP); however, nuclear electric propulsion (NEP) is also an integral part of this program and builds upon NASA's Base Research and Technology Program in power and electric propulsion as well as the SP-100 space nuclear power program. Although the Synthesis Group On America's SEI has identified NEP only as an option for cargo missions, recent studies conducted by NASA-Lewis show that NEP offers the potential for early manned Mars missions as well. Lower power NEP is also of current interest for outer planetary robotic missions. Current plans are reviewed for the overall nuclear propulsion project, with emphasis on NEP and those elements of NTP program which have synergism with NEP

  3. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2005-12-01

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, was re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for coal/IGCC powerplants. The new program was re-titled ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants''. This final report summarizes the work accomplished from March 1, 2003 to March 31, 2004 on the four original tasks, and the work accomplished from April 1, 2004 to July 30, 2005 on the two re-directed tasks. The program Tasks are summarized below: Task 1--IGCC Environmental Impact on high Temperature Materials: The first task was refocused to address IGCC environmental impacts on high temperature materials used in gas turbines. This task screened material performance and quantified the effects of high temperature erosion and corrosion of hot gas path materials in coal/IGCC applications. The materials of interest included those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: The second task was reduced in scope to demonstrate new technologies to determine the inservice health of advanced technology coal/IGCC powerplants. The task focused on two critical sensing needs for advanced coal/IGCC gas turbines: (1) Fuel Quality Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and detection of fuel impurities that could lead to rapid component degradation. (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware. Task 3--Advanced Methods for Combustion Monitoring and Control: The third task was originally to develop and validate advanced monitoring and control methods for coal/IGCC gas

  4. Nuclear electricity and Canada's domestic response to the Kyoto Protocol: modeling the economics of alternative scenarios

    International Nuclear Information System (INIS)

    Kanudia, A.; Loulou, R.; Morrison, R.; Pendergast, D.

    2001-03-01

    Canada's National Climate Change Process has undertaken extensive analysis of the implications of implementing the greenhouse gas reduction commitments of the Kyoto Protocol. The results of work undertaken by the Issue Tables are documented on the National Climate Change Process Internet World Wide Web site. The final reports from the Analysis and Modeling Group have been interpreted by some as evidence that nuclear energy has no role to play in reducing greenhouse gas emissions in Canada as it is uneconomic. Yet nuclear energy is a proven means of generating electricity in Canada that does not emit greenhouse gases and that can be economic under a range of circumstances. This paper reviews the analysis and modeling work to establish the reasons for this apparent anomaly. It turns out that modeling of nuclear electricity production is highly constrained by some of the modeling input assumptions initiated with the modeling work of the Electricity Table. These constraints were subsequently carried through to modeling of the entire Canadian economy. The constraints are derived from consideration of historical political, social and economic limitations on nuclear energy deployment and development, which may be overcome in a greenhouse gas constrained Canada. These constraints, which were imposed on decision and construction time, are not technical in nature and do not realistically reflect newer technology. A key modeling scenario is re-evaluated to consider the effect of a shorter decision time and to reflect current nuclear industry capability with respect to construction time. We also take into account revised input parameters to account for a reduced capital cost system which is the goal of the CANDU designer. These changes result in the model choosing more nuclear energy as a least cost source of electricity. The increase in nuclear electricity is substantial for the scenarios that investigate the role of reduced capital cost nuclear power plant systems. The

  5. Simulation language of DSNP: dynamic simulator for nuclear power-plants

    International Nuclear Information System (INIS)

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

  6. Level-one modules library for DSNP: Dynamic Simulator for Nuclear Power-plants

    International Nuclear Information System (INIS)

    Saphier, D.

    1978-09-01

    The Dynamic Simulator for Nuclear Power-plants (DSNP) is a system of programs and data sets by which a nuclear power plant or part thereof can be simulated at different levels of sophistication. The acronym DSNP is used interchangeably for the DSNP language, for the DSNP precompiler, for the DSNP libraries, and for the DSNP document generator. The DSNP language is a set of simple block oriented statements, which together with the appropriate data, comprise a simulation of a nuclear power plant. The majority of the DSNP statements will result in the inclusion of a simulated physical module into the program. FORTRAN statements can be inserted with no restrictions among DSNP statements

  7. Labor supply of engineers and scientists for nuclear electric utilities, 1987-1992

    International Nuclear Information System (INIS)

    Blair, L.M.

    1988-01-01

    An assessment of the adequacy of the supply of health physicists, nuclear engineers, and other engineers for the nuclear electric utility industry is based on job openings for scientists and engineers in broader nuclear-power-related fields, which include engineering and design, manufacturing, fabrication, supporting services, and government. In assessing the likely adequacy of labor supplies for commercial nuclear power job openings over the next 5 yr, consideration has been given to competing sources of labor demands, including nuclear energy research and development activities, nuclear defense, and the total US economy, and to the likely supply of new graduates. In particular, over the last 3 yr, the number of degrees awarded and enrollments in nuclear engineering programs have declined 12 and 14%, respectively, and in health physics programs, 5 and 14%, respectively. For health physics and nuclear engineers, tight labor market conditions (i.e. labor supplies and demand balanced at relatively high salaries) are expected over the next 5 yr because of declining enrollments and slowly growing employment levels plus job replacement needs. The commercial nuclear power field is expected to face tight labor markets for electrical and materials engineers because of strong competing demands in the economy. Other engineering occupations are likely to have adequate supplies for the nuclear power field but at salaries that continue to be relatively higher than salaries for other professional occupations

  8. Maximizing the science return of interplanetary missions using nuclear electric power

    International Nuclear Information System (INIS)

    Zubrin, R.M.

    1995-01-01

    The multi-kilowatt power sources on the spaecraft also enables active sensing, including radar, which could be used to do topographic and subsurface studies of clouded bodies such as Titan, ground pentrating sounding of Pluto, the major planet's moons, and planetoids, and topside sounding of the electrically conductive atmospheres of Jupiter, Saturn, Uranus and Neptune to produce profiles of fluid density, conductivity, and horizontal and vertical velocity as a function of depth and global location. Radio science investigations of planetary atmospheres and ring systems would be greatly enhanced by increased transmitter power. The scientific benefits of utilizing such techniques are discussed, and a comparison is made with the quantity and quality of science that a low-powered spacecraft employing RTGs could return. It is concluded that the non-propulsive benefits of nuclear power for spacecraft exploring the outer solar system are enormous, and taken together with the well documented mission enhancements enabled by electric propulsion fully justify the expanditures needed to bring a space qualified nuclear electric power source into being. copyright 1995 American Institute of Physics

  9. Specification errors in estimating cost functions: the case of the nuclear-electric-generating industry

    International Nuclear Information System (INIS)

    Jorgensen, E.J.

    1987-01-01

    This study is an application of production-cost duality theory. Duality theory is reviewed for the competitive and rate-of-return regulated firm. The cost function is developed for the nuclear electric-power-generating industry of the United States using capital, fuel, and labor factor inputs. A comparison is made between the Generalized Box-Cox (GBC) and Fourier Flexible (FF) functional forms. The GBC functional form nests the Generalized Leontief, Generalized Square Root Quadratic and Translog functional forms, and is based upon a second-order Taylor-series expansion. The FF form follows from a Fourier-series expansion in sine and cosine terms using the Sobolev norm as the goodness-of-fit measure. The Sobolev norm takes into account first and second derivatives. The cost function and two factor shares are estimated as a system of equations using maximum-likelihood techniques, with Additive Standard Normal and Logistic Normal error distributions. In summary, none of the special cases of the GBC function form are accepted. Homotheticity of the underlying production technology can be rejected for both GBC and FF forms, leaving only the unrestricted versions supported by the data. Residual analysis indicates a slight improvement in skewness and kurtosis for univariate and multivariate cases when the Logistic Normal distribution is used

  10. An overview of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite

    International Nuclear Information System (INIS)

    Voss, S.S.; Reynolds, E.L.

    1994-01-01

    Early in 1992 the idea of purchasing a Russian designed and fabricated space reactor power system and integrating it with a US designed satellite went from fiction to reality with the purchase of the first two Topaz II reactors by the Strategic Defense Initiative Organization (now the Ballistic Missile Defense Organization (BMDO)). The New Mexico Alliance was formed to establish a ground test facility in which to perform nonnuclear systems testing of the Topaz II, and to evaluate the Topaz II system for flight testing with respect to safety, performance, and operability. In conjunction, SDIO requested that the Applied Physics Laboratory in Laurel, MD propose a mission and design a satellite in which the Topaz II could be used as the power source. The outcome of these two activities was the design of the Nuclear Electric Propulsion Space Test Program (NEPSTP) satellite which combines a modified Russian Topaz II power system with a US designed satellite to achieve a specified mission. Due to funding reduction within the SDIO, the Topaz II flight program was postponed indefinitely at the end of Fiscal year 1993. The purpose of this paper is to present an overview of the NEPSTP mission and the satellite design at the time the flight program ended

  11. Regional analysis of the nuclear-electricity; Analisis regional de la nucleoelectricidad

    Energy Technology Data Exchange (ETDEWEB)

    Parera, M. D., E-mail: dparera@cnea.gov.ar [CNEA, Gerencia de Planificacion, Coordinacion y Control, Subgerencia de Planificacion Estrategica, Av. Gral. Paz 1499, B1650KNA San Martin, Buenos Aires (Argentina)

    2011-11-15

    In this study was realized a regional analysis of the Argentinean electric market contemplating the effects of regional cooperation, the internal and international interconnections; and the possibilities of insert of new nuclear power stations were evaluated in different regions of the country, indicating the most appropriate areas to carry out these facilities to increase the penetration of the nuclear energy in the national energy matrix. Also was studied the interconnection of the electricity and natural gas markets, due to the existent linking among both energy forms. With this purpose the program Message (Model for energy supply strategy alternatives and their general environmental impacts) was used, promoted by the International Atomic Energy Agency. This model carries out an economic optimization level country, obtaining the minimum cost as a result for the modeling system. The division for regions realized by the Compania Administradora del Mercado Mayorista Electrico (CAMMESA) was used, which divides to the country in eight regions. They were considered the characteristics and necessities of each one of them, their respective demands and offers of electric power and natural gas, as well as their existent and projected interconnections, composed by the electric lines and gas pipes. According to the results obtained through the model, the nuclear-electricity is a competitive option. (Author)

  12. The NASA program on nuclear electric propulsion: Preparing for the future

    International Nuclear Information System (INIS)

    Bennett, G.L.; Doherty, M.P.; Miller, T.J.

    1993-01-01

    In 1990 NASA reestablished its nuclear electric propulsion (NEP) program with the overall objective of developing the technology to support piloted missions to Mars, cargo missions to Mars and the Moon, and robotic science missions. With changing mission requirements and fiscal constraints the NEP program is now focused on studies of robotic science missions which are enabled or enhanced by NEP. These studies are closely coupled with the ongoing work on the SP-100 space nuclear reactor power system and, as such, include consideration of an early, low-power flight to demonstrate the technology and to perform a science missions. These studies have identified some possible mission candidates such as missions to Mars (including a study of Phobos and Deimos), missions to near-Earth asteroids, and missions to the Jovian Trojan asteroids. In addition, work proceeded on high-temperature components for power processing units and on high-power magnetoplasmadynamic thrusters. The paper will summarize the work and indicate future directions being considered for the program

  13. Nuclear electric propulsion /NEP/ spacecraft for the outer planet orbiter mission

    International Nuclear Information System (INIS)

    Garrison, P.W.; Nock, K.T.

    1982-01-01

    The design, operating features, and a possible Neptune orbit for the spacecraft powered by the SP-100 nuclear electric propulsion (NEP) system under study by NASA and the DOE are described. The system features a reactor and a payload situated on opposite ends of a 0.5 m diam, 11 m long astromast. Mercury-ion thrusters are located beneath the reactor for side thrusting, and no contamination of the payload or obstruction of the viewing angles for scientific objectives occurs with the system, which would not degrade in performance even under high insolation during near-sun maneuvers. Results of a theoretical study of earth escapes are presented to show that an NEP powered spiral trajectory out of a 700 km Shuttle orbit and using a Triton gravity assist would be superior to departing from a 300 km orbit with a Centaur boost. The mission profile includes a 1249 kg Galileo payload. The SP-100 has a 1.4 MWth reactor with UO2 fuel tiles and weighs 19,904 kg

  14. Teledyne Energy Systems, Inc., Proton Exchange Member (PEM) Fuel Cell Engineering Model Powerplant. Test Report: Initial Benchmark Tests in the Original Orientation

    Science.gov (United States)

    Loyselle, Patricia; Prokopius, Kevin

    2011-01-01

    Proton Exchange Membrane (PEM) fuel cell technology is the leading candidate to replace the alkaline fuel cell technology, currently used on the Shuttle, for future space missions. During a 5-yr development program, a PEM fuel cell powerplant was developed. This report details the initial performance evaluation test results of the powerplant.

  15. MOA: Magnetic Field Oscillating Amplified Thruster and its Application for Nuclear Electric and Thermal Propulsion

    International Nuclear Information System (INIS)

    Frischauf, Norbert; Hettmer, Manfred; Grassauer, Andreas; Bartusch, Tobias; Koudelka, Otto

    2006-01-01

    More than 60 years after the later Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other terrestrial applications can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilisation strategy. (authors)

  16. Life Cycle Greenhouse Gas Emissions of Nuclear Electricity Generation: Systematic Review and Harmonization

    International Nuclear Information System (INIS)

    Warner, E.S.; Heath, G.A.

    2012-01-01

    A systematic review and harmonization of life cycle assessment (LCA) literature of nuclear electricity generation technologies was performed to determine causes of and, where possible, reduce variability in estimates of life cycle greenhouse gas (GHG) emissions to clarify the state of knowledge and inform decision making. LCA literature indicates that life cycle GHG emissions from nuclear power are a fraction of traditional fossil sources, but the conditions and assumptions under which nuclear power are deployed can have a significant impact on the magnitude of life cycle GHG emissions relative to renewable technologies. Screening 274 references yielded 27 that reported 99 independent estimates of life cycle GHG emissions from light water reactors (LWRs). The published median, interquartile range (IQR), and range for the pool of LWR life cycle GHG emission estimates were 13, 23, and 220 grams of carbon dioxide equivalent per kilowatt-hour (g CO 2 -eq/kWh), respectively. After harmonizing methods to use consistent gross system boundaries and values for several important system parameters, the same statistics were 12, 17, and 110 g CO 2 -eq/kWh, respectively. Harmonization (especially of performance characteristics) clarifies the estimation of central tendency and variability. To explain the remaining variability, several additional, highly influential consequential factors were examined using other methods. These factors included the primary source energy mix, uranium ore grade, and the selected LCA method. For example, a scenario analysis of future global nuclear development examined the effects of a decreasing global uranium market-average ore grade on life cycle GHG emissions. Depending on conditions, median life cycle GHG emissions could be 9 to 110 g CO 2 -eq/kWh by 2050.

  17. 10 CFR 503.8 - No alternate power supply-general requirement for certain exemptions for new powerplants.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false No alternate power supply-general requirement for certain exemptions for new powerplants. 503.8 Section 503.8 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.8 No alternate power supply—general...

  18. The effect of coal-fired power-plant SO2 and NOx control technologies on aerosol nucleation in the source plumes

    Directory of Open Access Journals (Sweden)

    E. M. Knipping

    2012-12-01

    Full Text Available Nucleation in coal-fired power-plant plumes can greatly contribute to particle number concentrations near source regions. The changing emissions rates of SO2 and NOx due to pollution-control technologies over recent decades may have had a significant effect on aerosol formation and growth in the plumes with ultimate implications for climate and human health. We use the System for Atmospheric Modeling (SAM large-eddy simulation model with the TwO-Moment Aerosol Sectional (TOMAS microphysics algorithm to model the nucleation in plumes of coal-fired plants. We test a range of cases with varying emissions to simulate the implementation of emissions-control technologies between 1997 and 2010. We start by simulating the W. A. Parish power plant (near Houston, TX during this time period, when NOx emissions were reduced by ~90% and SO2 emissions decreased by ~30%. Increases in plume OH (due to the reduced NOx produced enhanced SO2 oxidation and an order-of-magnitude increase in particle nucleation in the plume despite the reduction in SO2 emissions. These results suggest that NOx emissions could strongly regulate particle nucleation and growth in power-plant plumes. Next, we test a range of cases with varying emissions to simulate the implementation of SO2 and NOx emissions-control technologies. Particle formation generally increases with SO2 emission, while NOx shows two different regimes: increasing particle formation with increasing NOx under low-NOx emissions and decreasing particle formation with increasing NOx under high-NOx emissions. Next, we compare model results with airborne measurements made in the W. A. Parish power-plant plume in 2000 and 2006, confirming the importance of NOx emissions on new particle formation and highlighting the substantial effect of background aerosol loadings on this process (the more polluted background of the 2006 case caused more than an order-of-magnitude reduction in particle formation in the plume compared to

  19. Atmospheric ice nuclei: No detectable effects from a coal-fired powerplant plume

    International Nuclear Information System (INIS)

    Schnell, R.C.; Van Valin, C.C.; Pueschel, R.F.

    1976-01-01

    Atmospheric ice nuclei were measured upwind and within the effluent plume of a coalfired powerplant during February 1976. Aerosol particles were captured on two types of membrane filters (Nuclepore and Millipore) and processed in two different thermal diffusion chambers, one calibrated to produce a 100% saturation relative to water and the other to produce a slight supersaturation relative to water. Consequently, the ice nuclei measured were active in the modes that are dominant in diffusion chambers, viz., deposition nucleation and condensation-followed-by-freezing nucleation. Results indicate that plume particles do not act as ice nuclei between the temperatures of -10 and -20degreeC, nor do combustion gases in the plume deactivate natural ice nuclei

  20. Supplement 1: Advanced nuclear turbojet powerplant characteristics summary for supersonic aircraft

    International Nuclear Information System (INIS)

    Larson, John W.

    1959-01-01

    The powerplant characteristics previously described in PWAC-275 were based on the use of low compressor pressure ratio nuclear turbojet engines equipped with interburners but without afterburners. The performance of an afterburning version of the same engine is presented in Section B of this supplement. The engine selection for the previous report and for Section B of this supplement was based on best engine performance at Mach No. 3 on nuclear heat alone. For this reason a low compression turbojet engine was selected. However, it is desirable that the nuclear data in report PWAC-275 be useful for both subsonic and supersonic missions. Therefore, the engine performance has been computed for a nuclear conversion of the Pratt & Whitney Aircraft J-58 turbojet engine which has a higher compressor pressure ratio. The performance of this engine is outlined in Section C of this supplement.

  1. Exergetic analysis and optimization of a solar-powered reformed methanol fuel cell micro-powerplant

    Science.gov (United States)

    Hotz, Nico; Zimmerman, Raúl; Weinmueller, Christian; Lee, Ming-Tsang; Grigoropoulos, Costas P.; Rosengarten, Gary; Poulikakos, Dimos

    The present study proposes a combination of solar-powered components (two heaters, an evaporator, and a steam reformer) with a proton exchange membrane fuel cell to form a powerplant that converts methanol to electricity. The solar radiation heats up the mass flows of methanol-water mixture and air and sustains the endothermic methanol steam reformer at a sufficient reaction temperature (typically between 220 and 300 °C). In order to compare the different types of energy (thermal, chemical, and electrical), an exergetic analysis is applied to the entire system, considering only the useful part of energy that can be converted to work. The effect of the solar radiation intensity and of different operational and geometrical parameters like the total inlet flow rate of methanol-water mixture, the size of the fuel cell, and the cell voltage on the performance of the entire system is investigated. The total exergetic efficiency comparing the electrical power output with the exergy input in form of chemical and solar exergy reaches values of up to 35%, while the exergetic efficiency only accounting for the conversion of chemical fuel to electricity (and neglecting the 'cost-free' solar input) is increased up to 59%. At the same time, an electrical power density per irradiated area of more than 920 W m -2 is obtained for a solar heat flux of 1000 W m -2.

  2. Epoxy-coal hydraulic insulation for structures of the Nurek Hydroelectric Powerplant

    Energy Technology Data Exchange (ETDEWEB)

    Sakharov, V I; Segal, M S; Solov' ev, I N; Yazev, R E

    1978-03-01

    The design of the Nurek Powerplant exposed the base of the core of the dam to a head of 270 m. To avoid seepage, it was decided to construct an antiseepage screen. Given the total hydraulic insulation area required, 26,540 m/sup 2/, the use of a metal screen would be quite expensive. It was therefore decided to use an epoxy-coal material consisting of a primer, varnish and enamel based on epoxy resins modified by the addition of coal tar, a waste product from the dry distillation of coal. A typical hydraulic insulation layer consists of a coat of primer, three or four coats of varnish and a coat of enamel. Glass-reinforced fabric is used with the first through third coats of varnish to increase crack resistance. The coating thus produced is found to be resistant to overbearing soil pressure of up to 600 t/m/sup 2/, hydrostatic head of up to 300 m and constant shear forces of up to 100 t/m/sup 2/. The method also saves labor and expensive metal.

  3. Development of a unified transport approach for the assessment of power-plant impact

    International Nuclear Information System (INIS)

    Akin, E.J.; Barton, J.M.; Bledsoe, J.L.

    1977-01-01

    Progress during the first 18 months in implementation of the Unified Transport Approach (UTA) is summarized in this report, which covers the period through December 1976. The goal of this project is to develop mathematical models for fast-transient, one-and two-dimensional transport of thermal, radiological, chemical, and biological properties in rivers, estuaries, lakes, and coastal regions for assessing the impact of power-plant operations. Development and validation of these models are illustrated in applications at several sites where data is available. The models include submodels for sediment transport, exchange of a soluble isotope with sediment, and zone-matching models to connect near-field problems of reentrainment and recirculation with far-field convective transport. Several types of automated data preparation have been introduced, and the codes have been designed to allow input of specified plant operating conditions for given durations. The UTA provides a common basis for calculating the transport of intensive quantities that depend on basic flow properties, which can be obtained from a common set of data for geometry, bathymetry, and meteorology that must be prepared only once. The formulation and calculation are based on a stable set of algorithms that have been tested and proven valid. The user can then focus on understanding and interpreting thermal, chemical, or radiological transport results with confidence that the basic calculations are direct, efficient, and meaningful. Recent work in each of the three areas is described

  4. Chief Joseph Kokanee Enhancement Project : Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at Grond Coulee Dam Third Powerplant Forebay.

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, M.A.; McKinstry, C.A.; Simmons, C.S.

    2002-01-01

    region or upstream. Fish were also swimming faster and straighter when the lights were on compared to off. (3) The behavioral results were most pronounced for medium- and large-sized fish at night. Medium-sized fish, based on acoustic target strength, were similar to the size of kokanee and rainbow trout released upstream of Grand Coulee Dam. Based on this study and general review of strobe lights, the researchers recommend several modifications and enhancements to the follow-on study in 2002. The recommendations include: (1) modifying the study design to include only the 24-hr on/off treatments, and controlling the discharge at the third powerplant, so it can be included as a design variable; and (2) providing additional data by beginning the study earlier (mid-May) to better capture the kokanee population, deploying an additional splitbeam transducer to sample the region close to the lights, and increasing the number of lights to provide better definition of the lit and unlit region.

  5. The development of the Nuclear Electric core performance and fault transient analysis code package in support of Sizewell B

    International Nuclear Information System (INIS)

    Hall, P.; Hutt, P.

    1994-01-01

    This paper describes Nuclear Electric's (NE) development of an integrated code package in support of all its reactors including Sizewell B, designed for the provision of fuel management design, core performance studies, operational support and fault transient analysis. The package uses the NE general purpose three-dimensional transient reactor physics code PANTHER with cross-sections derived in the PWR case from the LWRWIMS LWR lattice neutronics code. The package also includes ENIGMA a generic fuel performance code and for PWR application VIPRE-01 a subchannel thermal hydraulics code, RELAP5 the system thermal hydraulics transient code and SCORPIO an on-line surveillance system. The paper describes the capabilities and validation of the elements of this package for PWR, how they are coupled within the package and the way in which they are being applied for Sizewell B to on-line surveillance and fault transient analysis. (Author)

  6. Fuel switching in power-plants: Modelling and impact on the analysis of energy projects

    International Nuclear Information System (INIS)

    Varympopiotis, G.; Tolis, A.; Rentizelas, A.

    2014-01-01

    Highlights: • The impact of fuel-switching in electricity generation is researched. • 15 Scenarios of fuel-technology combinations are compared using a computational model. • Fuel-switching results to higher yields compared to single-fuelled plants. • Plants with natural gas combined cycle and solid fuel supercritical boilers are optimal. • Fuel-switching, offers higher flexibility and security of fuel supply. - Abstract: In electricity markets, where conditions are uncertain, the choice of the best technology and the optimisation of production processes may not anymore be enough to ensure optimal investment yield of energy business plans. Providing some aspects of flexibility might enhance their financial performance; fuel switching may prove to be an alternative option, offering operational flexibility over time, as well as significant financial benefits. Traditional investment analysis methods are considered marginally useful to analyse this case. Instead, the recent tools of time-dependent investment analysis are more appropriate, since they are not inherently restricted to immediate, irreversible decisions. In the present work, a time-dependent computational model is presented and applied in the case study of the Greek Power Sector, in order to estimate the potential advantages of the fuel switching concept. Moreover, the optimal timing of switching is derived, to ensure increasing yields of an average-capacity power-plant. The results of the research indicate significant financial benefits anticipated in most scenarios from applying fuel switching, compared to single-fuelled electricity generation units. Security of fuel supply and enhanced flexibility may also be offered to the power plant since more than one technology and fuels may be engaged

  7. TVA reaps big savings by letting powerplant work to outside firms

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This abstract is the entire text of the article. In a report to Congress, the Tennessee Valley Authority says its shift to full reliance on outside contractors for powerplant construction and modification work saved a net $54M in the first half of 1992. TVA says that total savings from lower overhead and increased efficiency were $75M, but that was partially offset by $21M in one-time mobilization/de-mobilization charges. TVA has a budget of $1.7B this year for new plant and equipment. That will rise to over $2B in the next two years. About 70% of the work involves nuclear plant work. Several members of Congress from the area criticized TVA in mid-1991 when it cut more than 5,000 hourly construction jobs and several hundred salaried construction jobs. The agency said the cuts let it concentrate on power production and promised to make semi-annual reports to Congress detailing the results of contracting out. In the agency's first report, TVA Chairman John Waters says that it saved $19.2M in personnel costs and staff overhead over the six-month period ending June 30, 1992. At the same time, $21.8M was saved through increased construction efficiency and productivity. Waters also says that the switch caused minimal impact on the local work force. Contractors employed 6,166 craft workers on their TVA projects at mid-year, compared with the 5,200 dropped by the agency in mid-1991

  8. Effects of effluents from a coal-fired, electric-generating powerplant on local ground water near Hayden, Colorado

    Science.gov (United States)

    Ellis, S.R.; Mann, P.G.

    1981-01-01

    Data were collected at the Hayden, Colo., powerplant for about a year during 1978-79 to monitor the effects of effluent and raw-water storage ponds on the local ground water, Sage Creek, and the Yampa River. The concentration of boron in wells downgradient from the effluent ponds indicated that the ponds were leaking, increasing the average boron concentrations in the ground water to a level in excess of the standards for agricultural use of water. Water from seeps, probably the best indicators of downgradient water quality, had average concentrations of boron two times that of the Colorado Department of Health (1977) standard for agricultural use of water. Chemical analyses of water from wells and the discharge weir downgradient from the raw-water storage ponds indicated these ponds are leaking. The effect of this leakage is that the water in wells downgradient from these ponds has a lower specific conductance and a lower boron concentration than the water in wells downgradient from the effluent ponds. The concentration of trace elements in the water from the wells and the discharge weir generally declined during the study, probably because the ground water was recovering from the effects of a plume from the raw-water pond previously used for fly-ash disposal. The effluents from the Hayden powerplant lowered the specific conductance and the iron and manganese concentrations, increased the concentration of boron, and had little or no effect on the selenium concentration in Sage Creek. Sage Creek had no discernible effect on the Yampa River because the volume of water in the Yampa River was so much greater. The effluents from the powerplant also had no discernible effect on the Yampa River. (USGS)

  9. Prediction of powerplant vibration using FRF data of FE model; Dentatsu kansu wo mochiita power plant shindo yosoku

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, T; Tsukahara, M; Sakaguchi, M; Takahashi, Y [Honda R and D Co. Ltd., Tokyo (Japan)

    1997-10-01

    For the purpose of shortening the development period, the estimation of powerplant vibration has become more important in the early design stage, and eigenvalue analysis by FEM is commonly used to solve this problem. Eigenvalue Analysis cannot directly predict vibration levels under running conditions that affect the durability of each component and the vibration of a car body. This paper presents a new approach using FRF data from FE models for accurate prediction of engine vibration under running conditions. By applying this approach to an in-line four cylinder engine, the predicted vibration is reasonably comparable with experimental results. 3 refs., 8 figs.

  10. Economic principles of optimizing mixed nuclear and non-nuclear electricity systems

    International Nuclear Information System (INIS)

    Gouni, L.

    1984-01-01

    In this chapter, an attempt will be made to show how and why, viewed from the economic angle, nuclear energy and electricity systems supplement each other, since the former requires large size facilities, and the latter provide already existing networks for the supply of all users. Consequently, it is primarily through the electric vector that the rational development of the nuclear industry may be ensured. Section 2.1 sets forth the essential rules for economic calculation. In Section 2.2 we discuss the competitive factors among final-use forms of energy in regard to utilization, and we attempt to show how nuclear energy transmitted through electricity systems may meet such terms. Finally, Section 2.3 deals with, and specifies the characteristics of, electricity systems based on nuclear energy and, in particular, the rates to which they lead. (author)

  11. Neutronics and Thermal Hydraulics Analysis of a Conceptual Ultra-High Temperature MHD Cermet Fuel Core for Nuclear Electric Propulsion

    Directory of Open Access Journals (Sweden)

    Jian Song

    2018-04-01

    Full Text Available Nuclear electric propulsion (NEP offers unique advantages for the interplanetary exploration. The extremely high conversion efficiency of magnetohydrodynamics (MHD conversion nuclear reactor makes it a highly potential space power source in the future, especially for NEP systems. Research on ultra-high temperature reactor suitable for MHD power conversion is performed in this paper. Cermet is chosen as the reactor fuel after a detailed comparison with the (U,ZrC graphite-based fuel and mixed carbide fuel. A reactor design is carried out as well as the analysis of the reactor physics and thermal-hydraulics. The specific design involves fuel element, reactor core, and radiation shield. Two coolant channel configurations of fuel elements are considered and both of them can meet the demands. The 91 channel configuration is chosen due to its greater heat transfer performance. Besides, preliminary calculation of nuclear criticality safety during launch crash accident is also presented. The calculation results show that the current design can meet the safety requirements well.

  12. Replacement energy costs for nuclear electricity-generating units in the United States: 1997--2001. Volume 4

    International Nuclear Information System (INIS)

    VanKuiken, J.C.; Guziel, K.A.; Tompkins, M.M.; Buehring, W.A.

    1997-09-01

    This report updates previous estimates of replacement energy costs for potential short-term shutdowns of 109 US nuclear electricity-generating units. This information was developed to assist the US Nuclear Regulatory Commission (NRC) in its regulatory impact analyses, specifically those that examine the impacts of proposed regulations requiring retrofitting of or safety modifications to nuclear reactors. Such actions might necessitate shutdowns of nuclear power plants while these changes are being implemented. The change in energy cost represents one factor that the NRC must consider when deciding to require a particular modification. Cost estimates were derived from probabilistic production cost simulations of pooled utility system operations. Factors affecting replacement energy costs, such as random unit failures, maintenance and refueling requirements, and load variations, are treated in the analysis. This report describes an abbreviated analytical approach as it was adopted to update the cost estimates published in NUREG/CR-4012, Vol. 3. The updates were made to extend the time frame of cost estimates and to account for recent changes in utility system conditions, such as change in fuel prices, construction and retirement schedules, and system demand projects

  13. The nuclear safety regulation in Japan and the response to changes of circumstances surrounding the nuclear electricity generation

    International Nuclear Information System (INIS)

    Hombu, K.; Hirota, M.; Taniguchi, T.; Tanaka, N.; Akimoto, S.

    2001-01-01

    The influences of external factors on nuclear safety are discussed in this paper, based on the views on the circumstances of nuclear electricity generation. The following external factors, which might have some potential impacts on nuclear safety, are selected for discussion: (1) The deregulation in the electricity generation industry; (2) The modification of approval/certification system in the regulation of electricity generation; (3) The influences on social atmosphere due to the occurrence of a series of troubles; (4) The government reform and the structural adjustment of industry and (5) Others. Our further discussion seems to focus on the following 2 issues: (a) Whether nuclear power and the other electrical sources should compete with each other for short term economical cost, or whether factors of cost stability and competitiveness as well as longer term energy supply security and global environmental issues ranging over several decades should be considered; (b) How to realize the appropriate regulation from the perspective of public acceptance and confidence (when a series of troubles occur) without imposing unnecessary burdens on industry and without jeopardizing safety. These issues may be common among many countries and can be widely discussed. (author)

  14. Nuclear Electric Propulsion mission engineering study covering the period April 1971 to January 1973. Volume I. Executive summary. Final report

    International Nuclear Information System (INIS)

    1973-03-01

    The results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions are presented. Critical technologies assessed are associated with the development of Nuclear Electric Propulsion (NEP), and the impact of its availability on future space programs. Specific areas of investigation include outer planet and comet rendezvous mission analysis, NEP Stage design for geocentric and interplanetary missions, NEP system development cost and unit costs, and technology requirements for NEP Stage development. A multimission NEP Stage can be developed to perform both multiple geocentric and interplanetary missions. Development program costs for a 1983 launch would be of the order of $275 M, including hardware and reactor development, flight system hardware, and mission support. Recurring unit costs for flight NEP systems would be of the order of $25 M for a 120 kWe NEP Stage. Identified pacing NEP technology requirements are the development of 20,000 full power hour ion thrusters and thermionic reactor, and the development of related power conditioning. The resulting NEP Stage design provides both inherent reliability and high payload mass capability. High payload mass capability can be translated into both low payload cost and high payload reliability. NEP Stage and payload integration is compatible with the Space Shuttle

  15. Nuclear Electric Propulsion mission engineering study covering the period April 1971 to January 1973. Volume II. Final report

    International Nuclear Information System (INIS)

    1973-03-01

    The results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions are summarized. Critical technologies assessed are associated with the development of Nuclear Electric Propulsion (NEP), and the impact of its availability on future space programs. Specific areas of investigation include outer planet and comet rendezvous mission analysis, NEP Stage design for geocentric and interplanetary missions NEP system development cost and unit costs, and technology requirements for NEP Stage development. A multi-mission NEP Stage can be developed to perform both multiple geocentric and interplanetary missions. Development program costs for a 1983 launch would be of the order of $275 M, including hardware and reactor development, flight system hardware, and mission support. Recurring unit costs for flight NEP systems would be of the order of $25 M for a 120kWe NEP Stage. Identified pacing NEP technology requirements are the development of 20,000 full power hour ion thrusters and thermionic reactor, and the development of related power conditioning. The resulting NEP Stage design provides both inherent reliability and high payload mass capability. High payload mass capability can be translated into both low payload cost and high payload reliability. NEP Stage and payload integration is compatible with the Space Shuttle

  16. Dungeness 'A' Nuclear Power Station. The findings of NII's assessment of Nuclear Electric's long term safety review

    International Nuclear Information System (INIS)

    1994-01-01

    The assessment is reported of Nuclear Electrics' Long Term Safety Reviews (LTSR) of the Dungeness A magnox reactors. The assessment was undertaken by the Health and Safety Executive's Nuclear Installations Inspectorate (NII) which is responsible for regulating the safety of nuclear installations in the United Kingdom. This was one of a programme of LTSRs for all the UK magnox reactors. The LTSR for each plant was proceeded by a Generic Issues programme. The results of both the LTSR and the Generic Issues programme have been used by NII in forming the conclusions of this assessment. Overall the safety case for Dungeness A is satisfactory for continued operation. A programme of additional modifications and inspections has been put in place which further enhances the safety justification. Reactor operations will continue to be monitored and regulated in accordance with the inspections required under the licensing arrangements. Provided these requirements and the agreed further analysis, improvements and inspections give satisfactory results it is expected that the station will be able to operate safely till each reactor is at least 30 years old. Beyond this point a further Periodic Safety Review will be required. (UK)

  17. Facts against nuclear electricity generation. An analysis of the current situation. 2. Enlarged ed. Fakten gegen den Atomstrom. Eine aktuelle Bestandsaufnahme

    Energy Technology Data Exchange (ETDEWEB)

    Buechele, C

    1986-01-01

    The book destroys a legend. The nuclear cartel still goes on telling the tale of safety, environmental compatibility and economic efficiency of nuclear electricity generation. But nothing in this story stands the test: Bare facts destroy the legend. Up to now, only insiders have been able to state counterarguments. The book in hand now presents in a nutshell all results and experience and facts to be brought forward against nuclear electricity generation. The material is presented in a problem-oriented, reliable and comprehensible manner. Anyone who long since suspected lies and malinformation of the public will step by step find the arguments justifying his suspicion. In an annex, Harald Gaber explains the Chernobyl disaster and its consequences. A literature index with comments is a helpful guide for further reading.

  18. The impossible dream? How Nuclear Electric, Ltd. pulled itself out of the ashes of government ownership and became highly competitive in a privatized and deregulating British power market

    International Nuclear Information System (INIS)

    Maycock, P.

    1998-01-01

    The day was dark for Nuclear Electric plc. when the British government decided it would privatize and deregulate the electric utility industry. For years, Nuclear Electric and other UK-based fossil power producers had been operating in a regulated market where the state set and guaranteed the price of electricity. All that was changing in Britain as the government introduced competition and as customers looked forward to purchasing power from the lowest bidder. Essentially the situation in England was much the same as it is now in the US: there was major momentum toward deregulation. The reality of competition in Britain came as good news to many power producers--in particular those who kept the lights on cost effectively. Others, However, weren't so optimistic, especially nuclear plants that traditionally bear higher safety and maintenance costs than their fossil counterparts. Taking its cues from the City (Britain's Wall Street), the British government simply considered nuclear generators to be unreliable, high cost, unprofitable organizations incapable of surviving in a privatized environment. It therefore left its nuclear power plants off the docket when selling (privatizing) its generating capacity. This paper describes how Nuclear Electric Ltd. became competitive in a deregulated environment

  19. Use of High-Power Brayton Nuclear Electric Propulsion (NEP) for a 2033 Mars Round-Trip Mission

    International Nuclear Information System (INIS)

    McGuire, Melissa L.; Martini, Michael C.; Packard, Thomas W.; Weglian, John E.; Gilland, James H.

    2006-01-01

    The Revolutionary Aerospace Systems Concepts (RASC) team, led by the NASA Langley Research Center, is tasked with exploring revolutionary new approaches to enabling NASA to achieve its strategic goals and objectives in future missions. This paper provides the details from the 2004-2005 RASC study of a point-design that uses a high-power nuclear electric propulsion (NEP) based space transportation architecture to support a manned mission to Mars. The study assumes a high-temperature liquid-metal cooled fission reactor with a Brayton power conversion system to generate the electrical power required by magnetoplasmadynamic (MPD) thrusters. The architecture includes a cargo vehicle with an NEP system providing 5 MW of electrical power and a crewed vehicle with an NEP system with two reactors providing a combined total of 10 MW of electrical power. Both vehicles use a low-thrust, high-efficiency (5000 sec specific impulse) MPD system to conduct a spiral-out of the Earth gravity well, a low-thrust heliocentric trajectory, and a spiral-in at Mars with arrival late in 2033. The cargo vehicle carries two moon landers to Mars and arrives shortly before the crewed vehicle. The crewed vehicle and cargo vehicle rendezvous in Mars orbit and, over the course of the 60-day stay, the crew conducts nine-day excursions to Phobos and Deimos with the landers. The crewed vehicle then spirals out of Martian orbit and returns via a low-thrust trajectory to conduct an Earth flyby. The crew separates from the vehicle prior to Earth flyby and aerobrakes for a direct-entry landing

  20. Recent activities within Nuclear Electric related to the qualification of digital systems and the extension of maintenance intervals

    International Nuclear Information System (INIS)

    Holt, G.P.

    1993-01-01

    Nuclear Electric is pursuing a program of modernization and enhancement of existing control and safety (C ampersand I) systems to improve power plant availability and increase power output. This paper describes recent experience in qualifying digital systems for safety applications. Also, described is the work currently in hand to reduce the frequency of maintenance periods for safety C ampersand I equipment. The qualification of digital systems is shown to be a more rigorous and much more extensive (and thus costly) exercise than the qualification of conventional equipment. This is illustrated by brief references to two software-based safety systems, the Single Channel Trip System at the Dungeness open-quotes Bclose quotesAGR and the Primary Protection System for the new PWR at Sizewell open-quotes Bclose quotes. The emphasis of the paper is on the use of Application Specific Integrated Circuits (ASICs) in safety systems, to reduce, or eliminate dependence on software for the fulfillment of requirements which need implementations that are complex or of a high functional density. Recent experience in the development of a prototype safety system based on ASICs, The Gaseous Activity Monitor and Trip Equipment (GAM), is used to illustrate their possible benefits and potential problems. When using complex integrated circuits like microprocessors or ASICs in digital systems a difficulty arises in analyzing the failure modes of the system. Efforts to overcome this difficulty led to the development of a method for performing failure analyses based on functional blocks. The techniques and benefits of such an approach are outlined. Finally, efforts to reduce maintenance costs, yet at the same time enhance safety, are leading towards an extension of maintenance intervals, for some safety equipment, from 3 months to 4 months and also towards lengthening the period between AGR outages from 2 years to 3 years

  1. Potential Role of Land Use and Land Cover Information in Powerplant Siting: Example of Three Mile Island

    Science.gov (United States)

    Wray, J. R.

    1982-01-01

    Selecting a site for a nuclear powerplant can be helped by digitizing land use and land cover data, population data, and other pertinent data sets, and then placing them in a geographic information system. Such a system begins with a set of standardized maps for location reference and then provides for retrieval and analysis of spatial data keyed to the maps. This makes possible thematic mapping by computer, or interactive visual display for decisionmaking. It also permits correlating land use area measurements with census and other data (such as fallout dosages), and the updating of all data sets. The system is thus a tool for dealing with resource management problems and for analyzing the interaction between people and their environment. An explanation of a computer-plotted map of land use and cover for Three Mile Island and vicinity is given.

  2. Independent Orbiter Assessment (IOA): Assessment of the electrical power generation/fuel cell powerplant subsystem FMEA/CIL

    Science.gov (United States)

    Brown, K. L.; Bertsch, P. J.

    1987-01-01

    Results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Generation/Fuel Cell Powerplant (EPG/FCP) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPG/FCP hardware.

  3. Compliance problems of small utility systems with the Powerplant and Industrial Fuel Use Act of 1978: volume II - appendices

    Energy Technology Data Exchange (ETDEWEB)

    None

    1981-01-01

    A study of the problems of compliance with the Powerplant and Industrial Fuel Use Act of 1978 experienced by electric utility systems which have a total generating capacity of less than 2000 MW is presented. This volume presents the following appendices: (A) case studies (Farmington, New Mexico; Lamar, Colorado; Dover, Delaware; Wolverine Electric Cooperative, Michigan; Central Telephone and Utilities, Kansas; Sierra Pacific Power Company, Nevada; Vero Beach, Florida; Lubbock, Texas; Western Farmers Cooperative, Oklahoma; and West Texas Utilities Company, Texas); (B) contacts and responses to study; (C) joint action legislation chart; (D) Texas Municipal Power Agency case study; (E) existing generating units jointly owned with small utilities; (F) future generating units jointly owned with small utilities; (G) Federal Register Notice of April 17, 1980, and letter of inquiry to utilities; (H) small utility responses; and (I) Section 744, PIFUA. (WHK)

  4. Nuclear electricity. 5. ed.

    International Nuclear Information System (INIS)

    Hore-Lacy, I.

    1999-01-01

    This new edition is updated, expanded and in a larger format than its predecessors. Also it is a joint undertaking with Canada, rather than simply an Australian perspective. It has a much expanded chapter on nuclear wastes and reprocessing, as well as more on the advanced reactors which are now coming into service. It also discusses nuclear reactor safety and safeguards issues. A final chapter looks at Australian and Canadian uranium mining

  5. Economics of nuclear electricity

    International Nuclear Information System (INIS)

    Frederick, G.

    1997-01-01

    On the sites of Tihange and Doel in Belgium, a total of seven nuclear generating units with an aggregate installed power of 5807 MWe are operated. Construction of another unit at Doel was postponed indefinitely in 1988 after the Chernobyl accident. Electrabel holds a 25% interest in the Chooz B-1 and B-2 nuclear generating units under construction in France near the Belgian border. In terms of gross installed nuclear generating capacity worldwide, Belgium holds twelfth place; when ranked according to the contribution to public electricity supply, the country holds third place with a 57% share. Before decisions are taken about future nuclear power plants, above all the fuel costs of gas-fired cogeneration plants and the capital costs of nuclear power plants must be weighed. Current evaluation of all costs shows the use of nuclear power for electricity generation to be ten percent more expensive than that of natural gas. However, those responsible in the power supply industry feel that this short-term competitive situation is only one factor out of many others, such as safety issues, diversification in sourcing and deliveries, climatic influences, and employment. The development and construction of advanced reactors will result in the desired cost reduction and lead to a new era of nuclear power, also in Europe. (orig.) [de

  6. Nuclear electricity from France?

    International Nuclear Information System (INIS)

    Harms, W.

    1987-01-01

    This second volume of the Berlin series presents the papers and discussion of the eleventh discussion meeting on energy law, for the first time held in Berlin, on May 12-13, 1987. The leading subject of the first conference day, namely electricity imports from France, has since then widely been discussed in the media or at other meetings, although the legal problems or obstacles revealed at this Berlin meeting are far from being solved. There is EdF's wish to export electricity to West Germany on the other hand, and there is the West German coal industry's scepticism on the other hand. Much is at stake for West Germany's national concept of enhanced use of coal for electricity generation, and the related system of subventions. Supply concepts and franchise charges, a standing topic of the power sector for quite a time now, have been discussed on the second conference day. The papers read there gave an account of the situation and also presented some new aspects. (orig./UA) [de

  7. Decree no. 487/72 of 5 December defining the rules to be complied with when setting up nuclear electricity generating plants

    International Nuclear Information System (INIS)

    1972-01-01

    This Decree was made in implementation of Decree-Law no. 49398 of 24 November 1969 establishing the licensing system for nuclear activities of an industrial nature in Portugal; it determines the licensing procedure for nuclear electricity-generating plants. The Decree lays down the conditions to be complied with for obtaining a licence, which is issued in three stages, prior to the activity. The three stages are: site approval; construction licence and operating licence. The operating licence is delivered by the competent authorities after they are satisfied that the final safety report conforms to requirements. (NEA) [fr

  8. Nuclear powerplant safety systems. Hearings before the Subcommittee on Energy Research and Production of the Committee on Science and Technology, House of Representatives, Ninety-Sixth Congress

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    The main objective of holding these hearings is to help the committee, and the Congress, and members of the public to understand the questions associated with nuclear powerplant safety. Also, to help the committee and the Congress to take what steps it feels necessary in assuring that our nuclear powerplants will be even safer in the future than they are today. Learning the lessons from Three Mile Island, asking the tough questions, and providing responsible answers to them will be part of the functioning of this committee. This committee has the responsibility for energy research, development, and demonstration associated with our nuclear powerplant research, development, and demonstration programs which ultimately will lead to commercialization. In conducting these hearings, the subcommittee intends to explore every aspect of safety technology and to conduct a thorough review of the status of the technology. The subcommittee wants to develop a detailed understanding of nuclear safety and operating philosophy as well as the implications of the Three Mile Island accident and any other accident

  9. Analysis of the performance of a passive hybrid powerplant to power a lightweight unmanned aerial vehicle for a high altitude mission

    Science.gov (United States)

    Renau, Jordi; Sánchez, Fernando; Lozano, Antonio; Barroso, Jorge; Barreras, Félix

    2017-07-01

    The objective of this research is to analyze the performance of a passive hybrid powerplant control system to be implemented in a lightweight unmanned aerial vehicle capable to ascend up to the high troposphere (10,000 m). The powerplant is based on a high-temperature PEM fuel cell connected in parallel to a set of lithium-polymer batteries and regulated by two power diodes. Test performed in steady state demonstrates that the use of the hybrid system increases the efficiency of the stack by more than 7% because the voltage at the main DC bus is limited by the batteries. The robustness of the passive control system is proved in a long-term test in which random perturbations of ±15% are applied to the average power that would be demanded during the ascent flight. The hybridization of the stack with the batteries eliminates sudden peaks in the current generated by the stack, which are responsible for prompt degradation phenomena that drastically reduce its useful lifetime. The study demonstrates that with the passive hybrid powerplant it is possible to reach the target height with the gas storage system considered in the application, contrary to what happens with the simple power plant.

  10. Inspecting operating nuclear powerplants: shortcomings in the Nuclear Regulatory Commission program. Fourth report by the Committee on Government Operations together with additional views

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Workers at every one of this Nation's 69 operating commercial nuclear powerplants conduct a constant vigil of great importance to this country's economy and to the health and safety of its citizens. They must constantly observe, assess and respond to the subtle and complex changes in the operating conditions of a reactor facility. They must do so skillfully enough to prevent major accidents and outages. It is for that reason that extraordinary efforts to train people to anticipate and understand unexpected events are necessary in the nuclear industry. It is for that reason that nuclear powerplant systems must be designed with unusually intricate safeguards against failure, that their maintenance must be meticulous and incessant, and that the condition of those systems must be constantly understood by nuclear plan management to prevent unanticipated degradation or breakdowns. Regrettably, facts disclosed by an oversight investigation by the Government Operations Subcommittee on Environment, Energy and Natural Resources indicate that those high standards have not yet been consistently attained by the nuclear industry or by the NRC. Significant mistakes in judgment and operational errors continue to occur at many operating nuclear powerplants, and the NRC inspection program too often fails to backstop the licensee. Utility failings are not discovered by the NRC in time to prevent costly and even dangerous mistakes from being made

  11. Systems analysis of radiation safety during dismantling of power-plant equipment at a nuclear power station

    International Nuclear Information System (INIS)

    Bylkin, B.K.; Shpitser, V.Ya.

    1993-01-01

    A systems analysis of the radiation safety makes possible an ad hoc determination of the elements forming the system, as well as the establishment of the characteristics of their interaction with radiation-effect factors. Here the authors will present part of the hierarchical analysis procedure, consisting in general of four separate procedures. The purpose is to investigate and analyze the mean and stable (on the average) indices of radiation safety, within the framework of alternative mathematical models of dismantling the power-plant equipment of a nuclear power station. The following three of the four procedures are discussed: (1) simulated projection, of the processing of radioactive waste; (2) analysis of the redistribution of radionuclides during the industrial cycle of waste treatment; (3) planning the collective dose load during the dismantling operation. Within the framework of the first of these procedures, the solutions to the problem of simulating a waste-treatment operation of maximum efficiency are analyzed. This analysis is based on the use of a data base for the parameters of the installations, assemblies, and equipment, enabling the integration of these in a simulation of a complex automated facility. The results were visualized in an AUTOCAD-10 medium using a graphical data base containing an explanation of the rooms

  12. Strategies and tactics of the negotiation for powerplant siting, model analysis of negotiation with the local fishermen's union, 2

    International Nuclear Information System (INIS)

    Wakatani, Yoshifumi; Yamanaka, Yoshiro

    1983-01-01

    Recently, the negotiation with local inhabitants in powerplant siting area is apt to drag on and is becoming more intricate. The purpose of this study is to present strategies and tactics for stepping up the negotiation more smoothly, taking the case of the negotiation with a fishermen's union. In this report, we obtained knowledge about the negotiation regarding compensation by the process as follows. (1) A gaming simulation model of the negotiation was built from the case study. This model reenacted the negotiation by having role-players represent the role of a power industry and fishermen's union. (2) Applying this model, 16 cases of simulated negotiations were carried out. As a result, similarities to actual negotiations were observed in the development of the negotiations and in the behavior of the interested party. We confirmed the model's ability to reproduce the negotiations. (3) Knowledge and information was also obtained by this simulation, concerning the developmental pattern of the negotiations, the effectiveness of measures for the promotion of fishery, the role of mediation, the utilization of preliminary negotiation, and so on. (author)

  13. Oil drilling rig diesel power-plant fuel efficiency improvement potentials through rule-based generator scheduling and utilization of battery energy storage system

    International Nuclear Information System (INIS)

    Pavković, Danijel; Sedić, Almir; Guzović, Zvonimir

    2016-01-01

    Highlights: • Isolated oil drilling rig microgrid power flows are analyzed over 30 days. • Rule-based diesel generator scheduling is proposed to reduce fuel consumption. • A battery energy storage is parameterized and used for peak load leveling. • The effectiveness of proposed hybrid microgrid is verified by simulations. • Return-of-investment might be expected within 20% of battery system lifetime. - Abstract: This paper presents the development of a rule-based energy management control strategy suitable for isolated diesel power-plants equipped with a battery energy storage system for peak load shaving. The proposed control strategy includes the generator scheduling strategy and peak load leveling scheme based on current microgrid active and reactive power requirements. In order to investigate the potentials for fuel expenditure reduction, 30 days-worth of microgrid power flow data has been collected on an isolated land-based oil drilling rig powered by a diesel generator power-plant, characterized by highly-variable active and reactive load profiles due to intermittent engagements and disengagements of high-power electric machinery such as top-drive, draw-works and mud-pump motors. The analysis has indicated that by avoiding the low-power operation of individual generators and by providing the peak power requirements (peak shaving) from a dedicated energy storage system, the power-plant fuel efficiency may be notably improved. An averaged power flow simulation model has been built, comprising the proposed rule-based power flow control strategy and the averaged model of a suitably sized battery energy storage system equipped with grid-tied power converter and state-of-charge control system. The effectiveness of the proposed rule-based strategy has been evaluated by means of computer simulation analysis based on drilling rig microgrid active and reactive power data recorded during the 30 day period. The analysis has indicated that fuel consumption of

  14. The production tax credit for wind turbine powerplants is an ineffective incentive

    International Nuclear Information System (INIS)

    Kahn, E.; California Univ., Berkeley, CA

    1996-01-01

    The US Energy Policy Act (EPAct) of 1992 created a production tax credit of 1.5c/kWh available for 10 years to promote certain renewable energy technologies, including wind turbines. This paper argues that the impact of the wind turbine production tax credit will be minimal. The argument depends entirely on the nature of the project finance structure used by the private power industry for wind turbine development. We show that tax credits can only be absorbed by equity investors if there is a large fraction of equity in the project capital structure. This raises the financing cost of wind turbine projects compared to conventional power technology, which relies on a large fraction of low cost debt. If the tax credit were paid as a cash subsidy, the capital structure could be shifted to low cost debt and financing costs could be significantly reduced. (Author)

  15. All 36 exactly solvable solutions of eigenvalues for nuclear electric quadrupole interaction Hamiltonian and equivalent rigid asymmetric rotor with expanded characteristic equation listing

    Energy Technology Data Exchange (ETDEWEB)

    Menke, Lorenz Harry, E-mail: lnz2004@mindspring.com [University of Pittsburgh (United States)

    2012-05-15

    This paper derives all 36 analytical solutions of the energy eigenvalues for nuclear electric quadrupole interaction Hamiltonian and equivalent rigid asymmetric rotor for polynomial degrees 1 through 4 using classical algebraic theory. By the use of double-parameterization the full general solution sets are illustrated in a compact, symmetric, structural, and usable form that is valid for asymmetry parameter {eta} is an element of (- {infinity}, + {infinity}). These results are useful for code developers in the area of Perturbed Angular Correlation (PAC), Nuclear Quadrupole Resonance (NQR) and rotational spectroscopy who want to offer exact solutions whenever possible, rather that resorting to numerical solutions. In addition, by using standard linear algebra methods, the characteristic equations of all integer and half-integer spins I from 0 to 15, inclusive are represented in a compact and naturally parameterized form that illustrates structure and symmetries. This extends Nielson's listing of characteristic equations for integer spins out to I = 15, inclusive.

  16. Powerplant and Industrial Fuel Use Act, PL 95-620: legislative history, 1978

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    Hearings continued on H.R. 6831, the President's proposed National Energy Act. Witnesses aired views on the impacts that industries would experience on converting boilers to coal. The final hearing of the three-week session was held on June 1, 1977. The June 1 session took a step back from the details of the many components of the President's plan and took a broad and longer term view of the plan as a whole. The hearings elicited substantial criticism of the many costs and burdens that would accompany the President's program. This is largely because the costs of conservation and conversion to coal precede the benefits by several years. A summary of the National Energy Plan is presented. (MCW)

  17. Short-term regulation of hydro powerplants. Studies on the environmental effects

    International Nuclear Information System (INIS)

    Sinisalmi, T.; Riihimaeki, J.; Vehanen, T.; Yrjaenae, T.

    1997-01-01

    The publication is a final report on a project studying effects of short-term regulation of hydro power plants. The project consists of two parts: (1) examining and developing methods for evaluation, (2) applying methods in a case study at the Oulujoki River. The economic value of short-term regulation was studied with a model consisting of an optimization model and a river simulation model. Constraints on water level or discharge variations could be given to the power plants and their economical influence could be studied. Effects on shoreline recreation use due to water level fluctuation were studied with a model where various effects are made commensurable and expressed in monetary terms. A literature survey and field experiments were used to study the methods for assessing effects of short-term regulation on river habitats. The state and development needs of fish stocks and fisheries in large regulated rivers were studied and an environmental classification was made. Remedial measures for the short-term regulated rivers were studied with a literature survey and enquiries. A comprehensive picture of the various effects of short-term regulation was gained in the case study in Oulujoki River (110 km long, 7 power plants). Harmful effects can be reduced with the given recommendations of remedial measures on environment and the usage of the hydro power plants. (orig.) 52 refs

  18. Community leaders' perspectives on socio-economic impacts of power-plant development

    International Nuclear Information System (INIS)

    Hastings, M.; Cawley, M.E.

    1981-01-01

    The primary focus of this research effort was to identify and measure the socioeconomic impacts of power plant development on non-metropolitan host communities. A mail survey, distributed to community leaders in 100 power plant communities east of the Mississippi River, was utilized to gather information from 713 respondents. Community leaders were questioned as to the plant's impact on (a) community groups, (b) aspects of community life, (c) overall community acceptance and (d) attitudes toward power plant development. Overall, the trends and patterns of plant impact on the host communities were found to be largely positive. Specifically, local employment opportunities were generally enhanced with the advent of the power plant. Directly related to power plant development was the overall improvement of the local economic situation. Off-shoots from such in the economic area included related general improvements in the community quality of life. While the vast majority of community leaders responded with positive comments on power plant presence, adverse impacts were also mentioned. Negative comments focused on environmental problems, deterioration of roads and traffic conditions, and the possibility of nuclear accidents. Despite these negative impacts, almost two-thirds of the community leaders would definitely support the reconstruction of the same energy facility. Power plant development, therefore, is generally perceived as both a positive and beneficial asset for the host area. (author)

  19. Short-term regulation of hydro powerplants. Studies on the environmental effects

    Energy Technology Data Exchange (ETDEWEB)

    Sinisalmi, T. [ed.; Forsius, J.; Muotka, J.; Soimakallio, H. [Imatran Voima Oy, Vantaa (Finland); Riihimaeki, J. [VTT, Espoo (Finland); Vehanen, T. [Finnish Game and Fisheries Research Inst. (Finland); Yrjaenae, T. [North Ostrobothnia Regional Environmental Centre, Oulu (Finland)

    1997-12-31

    The publication is a final report on a project studying effects of short-term regulation of hydro power plants. The project consists of two parts: (1) examining and developing methods for evaluation, (2) applying methods in a case study at the Oulujoki River. The economic value of short-term regulation was studied with a model consisting of an optimization model and a river simulation model. Constraints on water level or discharge variations could be given to the power plants and their economical influence could be studied. Effects on shoreline recreation use due to water level fluctuation were studied with a model where various effects are made commensurable and expressed in monetary terms. A literature survey and field experiments were used to study the methods for assessing effects of short-term regulation on river habitats. The state and development needs of fish stocks and fisheries in large regulated rivers were studied and an environmental classification was made. Remedial measures for the short-term regulated rivers were studied with a literature survey and enquiries. A comprehensive picture of the various effects of short-term regulation was gained in the case study in Oulujoki River (110 km long, 7 power plants). Harmful effects can be reduced with the given recommendations of remedial measures on environment and the usage of the hydro power plants. (orig.) 52 refs.

  20. Chief Joseph Kokanee Enhancement Project; Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at the Grand Coulee Dam Third Powerplant Forebay, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, M.; McKinstry, C.; Cook, C.

    2004-01-01

    Since 1995, the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes) have managed the Chief Joseph Kokanee Enhancement Project as part of the Northwest Power Planning Council (NWPPC) Fish and Wildlife Program. Project objectives have focused on understanding natural production of kokanee (a land-locked sockeye salmon) and other fish stocks in the area above Grand Coulee and Chief Joseph Dams on the Columbia River. A 42-month investigation from 1996 to 1999 determined that from 211,685 to 576,676 fish were entrained annually at Grand Coulee Dam. Analysis of the entrainment data found that 85% of the total entrainment occurred at the dam's third powerplant. These numbers represent a significant loss to the tribal fisheries upstream of the dam. In response to a suggestion by the NWPPC Independent Scientific Review Panel, the scope of work for the Chief Joseph Kokanee Enhancement Project was expanded to include a multiyear pilot test of a strobe light system to help mitigate fish entrainment. This report details the work conducted during the third year of the strobe light study by researchers of the Colville Confederated Tribes in collaboration with the Pacific Northwest National Laboratory. The objective of the study is to determine the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee and rainbow trout under field conditions. The prototype system consists of six strobe lights affixed to an aluminum frame suspended 15 m vertically underwater from a barge secured in the center of the entrance to the third powerplant forebay. The lights, controlled by a computer, illuminate a region directly upstream of the barge. The 2003 study period extended from June 16 through August 1. Three light treatments were used: all six lights on for 24 hours, all lights off for 24 hours, and three of six lights cycled on and off every hour for 24 hours. These three treatment conditions were assigned randomly

  1. Chief Joseph Kokanee Enhancement Project; Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at the Grand Coulee Dam Third Powerplant Forebay, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.; McKinstry, C.; Cook, C. [Pacific Northwest National Laboratory

    2005-02-01

    This report documents a four-year study(a) to assess the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee (Oncorhynchus nerka kennerlyi) and rainbow trout (O. mykiss) at the entrance to the forebay of the third powerplant at Grand Coulee Dam. The work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by Pacific Northwest National Laboratory (PNNL) in conjunction with the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes). In this report, emphasis is placed on the methodology and results associated with the fourth project year and compared with findings from the previous years to provide an overall project summary. Since 1995, the Colville Confederated Tribes have managed the Chief Joseph Kokanee Enhancement Project as part of the Northwest Power and Conservation Council Fish and Wildlife Program. Project objectives have focused on understanding natural production of kokanee (a land-locked sockeye salmon) and other fish stocks in the area above Grand Coulee and Chief Joseph dams on the Columbia River (Figure S.1). A 42-month investigation from 1996 to 1999 determined that from 211,685 to 576,676 fish, including kokanee and rainbow trout, were entrained annually at Grand Coulee Dam. Analysis of the data found that 85% of the total entrainment occurred at the dam's third powerplant. Because these entrainment rates represent a significant loss to the tribal fisheries upstream of the dam, they have been judged unacceptable to fishery managers responsible for perpetuating the fishery in Lake Roosevelt. In an effort to reduce fish entrainment rates, the scope of work for the Chief Joseph Kokanee Enhancement Project was modified in 2001 to include a multiyear study of the efficacy of using strobe lights to deter fish from entering the third powerplant forebay. Pacific Northwest National Laboratory initiated the four-year study in collaboration with Colville

  2. Coal and nuclear electricity fuels

    International Nuclear Information System (INIS)

    Rahnama, F.

    1982-06-01

    Comparative economic analysis is used to contrast the economic advantages of nuclear and coal-fired electric generating stations for Canadian regions. A simplified cash flow method is used with present value techniques to yield a single levelized total unit energy cost over the lifetime of a generating station. Sensitivity analysis illustrates the effects of significant changes in some of the cost data. The analysis indicates that in Quebec, Ontario, Manitoba and British Columbia nuclear energy is less costly than coal for electric power generation. In the base case scenario the nuclear advantage is 24 percent in Quebec, 29 percent in Ontario, 34 percent in Manitoba, and 16 percent in British Columbia. Total unit energy cost is sensitive to variations in both capital and fuel costs for both nuclear and coal-fuelled power stations, but are not very sensitive to operating and maintenance costs

  3. Nuclear electricity - a progress report

    International Nuclear Information System (INIS)

    England, G.

    1980-01-01

    A survey of the progress of nuclear power over the past three years reveals three major features: (i) the continued operation of the first generation of commercial nuclear power stations, based on the Magnox gas-cooled reactor; (ii) the introduction and operation of the first of the second-generation stations, based on the advanced gas-cooled reactor (AGR); and (iii) the commitment of two successive Governments to a flexible thermal reactor strategy. Each of these features is considered and a number of related issues, including the safety record and cost savings to the electricity consumer, are discussed. (author)

  4. Chief Joseph Kokanee Enhancement Project; Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at the Grand Coulee Dam Third Powerplant Forebay, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, R.; McKinstry, C.; Simmons, C. (Pacific Northwest National Laboratory)

    2003-01-01

    Since 1995, the Confederated Tribes of the Colville Reservation (Colville Confederated Tribes) have managed the Chief Joseph Kokanee Enhancement Project as part of the Northwest Power Planning Council (NWPPC) Fish and Wildlife Program. Project objectives have focused on understanding natural production of kokanee (a land-locked sockeye salmon) and other fish stocks in the area above Grand Coulee and Chief Joseph Dams on the Columbia River. A 42-month investigation concluded that entrainment at Grand Coulee Dam ranged from 211,685 to 576,676 fish annually. Further analysis revealed that 85% of the total entrainment occurred at the dam's third powerplant. These numbers represent a significant loss to the tribal fisheries upstream of the dam. In response to a suggestion by the NWPPC Independent Scientific Review Panel, the scope of work for the Chief Joseph Kokanee Enhancement Project was expanded to include a multiyear pilot test of a strobe light system to help mitigate fish entrainment. This report details the work conducted during the second year of the study by researchers of the Colville Confederated Tribes in collaboration with the Pacific Northwest National Laboratory. The 2002 study period extended from May 18 through July 30. The objective of the study was to determine the efficacy of a prototype strobe light system to elicit a negative phototactic response in kokanee and rainbow trout. The prototype system consisted of six strobe lights affixed to an aluminum frame suspended vertically underwater from a barge secured in the center of the entrance to the third powerplant forebay. The lights, controlled by a computer, were aimed to illuminate a specific region directly upstream of the barge. Three light level treatments were used: 6 of 6 lights on, 3 of 6 lights on, and all lights off. These three treatment conditions were applied for an entire 24-hr day and were randomly assigned within a 3-day block throughout the study period. A seven

  5. The influence of Goiania radiological accident on Brazilian public opinion concerning new nuclear electric plants; A influencia do acidente radiologico de Goiania na aceitacao publica de novas usinas nucleoeletricas

    Energy Technology Data Exchange (ETDEWEB)

    Meldonian, Nelson Leon; Mattos, Luis Antonio Terribile de [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Grupo de Energia e Ambiente

    1997-12-31

    The Brazilian society is against applications of nuclear energy, mainly respecting to construction of new nuclear power plants, believing that they are harmful to population`s welfare and the environment. By this reason, Brazilian nuclear sector would promote a more intensive program of public discussion, not limited to technical and scientific community. Intending to contribute to a better judgment by society about the differences between diverse employment of nuclear energy, arguments concerned to its benefits are presented, pointing out that adverse accounts to nuclear electricity based on Goiania radiological accident, are not justified 10 refs., 5 tabs.; e-mail: meldonia at net.ipen.br

  6. Changes in engineering-geological conditions in the foundation of the Bratsk hydroelectric powerplant dam during 15 years of operation

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, G K; Savinskaya, M K; Tizdel, R R; Sotnikova, N P

    1978-04-01

    Field observations of the rock foundation beneath the Bratsk Hydropower Dam have been conducted continuously and carefully, beginning during the period of construction. The dam is a concrete gravity dam with expanded seams, 125 m in height and 924 m in length. The head is 106 m. The dam was constructed in 42 column sections which were subsequently cemented together. The anchor of the dam is up to 15 m deep. Two rows of drainage wells 30 m deep and 3 m apart were drilled into the foundation beneath the dam. The observations indicate that the status of the foundation and the stability of the channel and left bank earth dam are quite satisfactory. The changes in engineering and geological conditions that are unavoidable upon construction of a large dam have apparently been completed, and the new conditions in the foundation of the dam have stabilized. The drainage devices are operating normally. However, observations should be continued at full volume.

  7. An application of the Proper Orthogonal Decomposition method to the thermo-economic optimization of a dual pressure, combined cycle powerplant

    International Nuclear Information System (INIS)

    Melli, Roberto; Sciubba, Enrico; Toro, Claudia

    2014-01-01

    Highlights: • The CCGT is modelled and simulated in CAMEL-Pro. • Economic costs of the system product are computed. • The POD–RBF procedure is applied to the thermoeconomic optimization of a CCGT power plant. • Economic optimal configuration is identified with POD–RBF procedure. - Abstract: This paper presents a thermo-economic optimization of a combined cycle power plant obtained via the Proper Orthogonal Decomposition–Radial Basis Functions (POD–RBF) procedure. POD, also known as “Karhunen–Loewe decomposition” or as “Method of Snapshots” is a powerful mathematical method for the low-order approximation of highly dimensional processes for which a set of initial data is known in the form of a discrete and finite set of experimental (or simulated) data: the procedure consists in constructing an approximated representation of a matricial operator that optimally “represents” the original data set on the basis of the eigenvalues and eigenvectors of the properly re-assembled data set. By combining POD and RBF it is possible to construct, by interpolation, a functional (parametric) approximation of such a representation. In this paper the set of starting data for the POD–RBF procedure has been obtained by the CAMEL-Pro™ process simulator. The proposed procedure does not require the generation of a complete simulated set of results at each iteration step of the optimization, because POD constructs a very accurate approximation to the function described by a relatively small number of initial simulations, and thus “new” points in design space can be extrapolated without recurring to additional and expensive process simulations. Thus, the often taxing computational effort needed to iteratively generate numerical process simulations of incrementally different configurations is substantially reduced by replacing much of it by easy-to-perform matrix operations. The object of the study was a fossil-fuelled, combined cycle powerplant of

  8. Advanced technology for nuclear powerplants

    International Nuclear Information System (INIS)

    Rohm, H.H.

    1987-01-01

    Advanced technology offers significant potential benefit to the nuclear industry. Improvements can be anticipated in plant performance, reliability, and overall plant safety as well as reduced life cycle costs. Utilizing artificial intelligence and expert systems, robotics, advanced instruments and controls, and modularization technologies can enhance plant operations and provide new insights and perspectives to plant risk and thus focus resources to areas of importance. Plant reliability, operability, availability, accident interdiction and limitation, and plant recovery are expected to improve. However, utilizing these technologies is not an automatic process. In addition to the actual costs associated with developing and implementing the technologies, operator training and acceptance represents a potential significant problem. Traditional plant operators have little or no experience with computer technology. There has already been some difficulty getting nuclear plant operators to accept and use the new technologies that have been implemented to accept and use the new technologies that have been implemented thus far

  9. Phase 9 update (1987) report for the Energy Economic Data Base Program EEDB-IX

    International Nuclear Information System (INIS)

    1988-07-01

    This document is a review of the 1987 update of detailed reference powerplant cost estimates. This distribution is the latest in a series published since 1978. The overall program purpose is to provide periodically updated, detailed base construction cost estimates for large nuclear electric operating plants. These data, which are representative of current US powerplant construction cost experience, are a useful contribution to program planning by the Office of the Assistant Secretary for Nuclear Energy. The ninth update includes three new models as a basis for projecting future costs of both small and large nuclear power plants and examining the potential for cost reduction by incorporation of improved and advanced design features. The models designated as improved include the advantages of modular construction and standardized approach to design and construction. The advanced model includes many of the features of the improved data models as well as application of passive or near-passive safety systems and design simplification

  10. Some ecological guidelines for large-scale biomass plantations

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, W.; Cook, J.H.; Beyea, J. [National Audubon Society, Tavernier, FL (United States)

    1993-12-31

    The National Audubon Society sees biomass as an appropriate and necessary source of energy to help replace fossil fuels in the near future, but is concerned that large-scale biomass plantations could displace significant natural vegetation and wildlife habitat, and reduce national and global biodiversity. We support the development of an industry large enough to provide significant portions of our energy budget, but we see a critical need to ensure that plantations are designed and sited in ways that minimize ecological disruption, or even provide environmental benefits. We have been studying the habitat value of intensively managed short-rotation tree plantations. Our results show that these plantations support large populations of some birds, but not all of the species using the surrounding landscape, and indicate that their value as habitat can be increased greatly by including small areas of mature trees within them. We believe short-rotation plantations can benefit regional biodiversity if they can be deployed as buffers for natural forests, or as corridors connecting forest tracts. To realize these benefits, and to avoid habitat degradation, regional biomass plantation complexes (e.g., the plantations supplying all the fuel for a powerplant) need to be planned, sited, and developed as large-scale units in the context of the regional landscape mosaic.

  11. Technical reference book for the Energy Economic Data Base Program: EEDB Phase 9 (1987)

    International Nuclear Information System (INIS)

    1988-07-01

    This document provides the current technical design bases for each technical data model (of and electric generating plant) in the eighth update. It contains a set of detailed system design descriptions (supplemented with engineering drawings) for the technical data models. This distribution is the latest in a series published since 1978. The overall program purpose is to provide periodically updated, detailed base construction cost estimates for large nuclear electric operating plants. These data, which are representative of current US powerplant construction cost experience, are a useful contribution to program planning by the Office of the Assistant Secretary for Nuclear Energy

  12. Perspectives for nuclear electricity in Central Africa

    International Nuclear Information System (INIS)

    Wa Kalenga, M.

    1977-01-01

    The paper analyses the energy system of the Central African countries and evaluates the projected global demand of energy. It compares the economy of the nuclear solution for satisfying future demands in relation to other forms of energy available in the region. Finally, it discusses the role that the countries involved can play in the fuel cycle (supply of raw material, possibilities of fuel enrichment). (author)

  13. Reactor design for nuclear electric propulsion

    International Nuclear Information System (INIS)

    Koenig, D.R.; Ranken, W.A.

    1979-01-01

    Conceptual design studies of a nuclear power plant for electric propulsion of spacecrafts have been on going for several years. An attractive concept which has evolved from these studies and which has been described in previous publications, is a heat-pipe cooled, fast spectrum nuclear reactor that provides 3 MW of thermal energy to out-of-core thermionic converters. The primary motivation for using heat pipes is to provide redundancy in the core cooling system that is not available in gas or liquid-metal cooled reactors. Detailed investigation of the consequences of heat pipe failures has resulted in modifications to the basic reactor design and has led to consideration of an entirely different core design. The new design features an integral laminated core configuration consisting of alternating layers of UO 2 and molybdenum sheets that span the entire diameter of the core. Design characteristics are presented and compared for the two reactors

  14. Protocol for a nuclear-electric battery

    International Nuclear Information System (INIS)

    Schachter, M.M.

    1993-01-01

    Carbon-14 exists in all living things in the amount capable of 3.8 picoCuries disintegrations per second to nitrogen-14. The emission are beta-rays, which are electrons of translational energy of approximately half million electron-Volts. By themselves these electrons are capable of excitation of luminescence from a phosphor. If the carbon-14 is within Angstroms of an element heavier than calcium, the emitted electrons will excite X-rays if they impinge on these vicinal atoms. The phenomenon is known as the Compton effect (recoil electrons). The X-rays are also capable of excitation of luminescence from phosphors. Anilin-aniliniumfluran chloride a fluorophor that emits near infrared radiation peaking at the 9,000 through 12,000 Angstroms band. Copper-copper(I)oxide having a monomolecular silver epitaxial coating will act as a photovoltaic cell producing approximately 0.238 Volt at 10 milliamperes in zenith sunlight per square centimeter. One gram of finely pulverized oyster shell (99% calcium carbonate) when mixed intimately with a substance containing a heavy element such as lead sulfide will bring the emitted electrons at relativistic velocity close enough to produce recoil electrons when they impinge on the lead atoms to produce X-rays. Spreading this mixture evenly on a 25 millimeter copper-copper(I)oxide silver epitaxially coated photocell produces a current of approximately 100 picoAmperes at 0.199 Volt detectable with an eleven megOhm impedance cathode-ray oscilloscope

  15. Perspectives for nuclear electricity in central Africa

    International Nuclear Information System (INIS)

    Wa Kalenga, M.

    1977-01-01

    The paper analyses the energetic system of Central African countries and evaluate the projected global demand of energy. It compares the economy of the nuclear solution for the satisfaction of future demand versus other forms of energy available in the region. It appreciates finally the role that the countries involved can play in the fuel cycle (supply of raw material, possibilities of fuel enrichment) [fr

  16. Table of Nuclear Electric Quadrupole Moments

    International Nuclear Information System (INIS)

    Stone, N.J.

    2013-12-01

    This Table is a compilation of experimental measurements of static electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin and parity are given, along with a brief indication of the method and any reference standard used in the particular measurement. Experimental data from all quadrupole moment measurements actually provide a value of the product of the moment and the electric field gradient [EFG] acting at the nucleus. Knowledge of the EFG is thus necessary to extract the quadrupole moment. A single recommended value of the moment is given for each state, based, for each element, wherever possible, upon a standard reference moment for a nuclear state of that element studied in a situation in which the electric field gradient has been well calculated. For several elements one or more subsidiary reference EFG/moment references are required and their use is specified. The literature search covers the period to mid-2013. (author)

  17. Large deviations

    CERN Document Server

    Varadhan, S R S

    2016-01-01

    The theory of large deviations deals with rates at which probabilities of certain events decay as a natural parameter in the problem varies. This book, which is based on a graduate course on large deviations at the Courant Institute, focuses on three concrete sets of examples: (i) diffusions with small noise and the exit problem, (ii) large time behavior of Markov processes and their connection to the Feynman-Kac formula and the related large deviation behavior of the number of distinct sites visited by a random walk, and (iii) interacting particle systems, their scaling limits, and large deviations from their expected limits. For the most part the examples are worked out in detail, and in the process the subject of large deviations is developed. The book will give the reader a flavor of how large deviation theory can help in problems that are not posed directly in terms of large deviations. The reader is assumed to have some familiarity with probability, Markov processes, and interacting particle systems.

  18. Large deviations

    CERN Document Server

    Deuschel, Jean-Dominique; Deuschel, Jean-Dominique

    2001-01-01

    This is the second printing of the book first published in 1988. The first four chapters of the volume are based on lectures given by Stroock at MIT in 1987. They form an introduction to the basic ideas of the theory of large deviations and make a suitable package on which to base a semester-length course for advanced graduate students with a strong background in analysis and some probability theory. A large selection of exercises presents important material and many applications. The last two chapters present various non-uniform results (Chapter 5) and outline the analytic approach that allow

  19. Perspectives at the East European engineering companies in the field of power industry in the power-plant construction globalization conditions

    International Nuclear Information System (INIS)

    Ganchev, R.

    2001-01-01

    A large group of companies, institutes, boiler and power engineering work ect. from East European countries, currently in process of reorganization or already transformed into new-established private companies and corporations possess significant intellectual property in the field of thermal power technologies and equipment and broad experience in the design and the erection of thermal power plants. In many cases this know-how is not only competitive to that of the large companies of the West and of the Far East, but frequently it also proves to have a number of advantages. However, in the years of transition in these countries and simultaneous globalization, the owners of this potentials meet with difficulties and restrictions to realize it fully. Large investment projects - for new or replacement capacities or comprehensive rehabilitation or refurbishment of TPPs - are accessible only for the financially powerful EPC-contractors and key equipment suppliers, for which large bank credits are accessible. The near future perspective, for the scientists and experts that have accumulated this capital, is in the opportunity to employ the extensive experience and know-how of this firms in the forthcoming large-scale rehabilitation projects in these countries, and primarily, in the solution of specific problems, that have not been solved so far, provided that the projects are awarded not on the basis of the financial power of the contractors but on the basis of the efficiency of the proposed original solutions

  20. Large ethics.

    Science.gov (United States)

    Chambers, David W

    2008-01-01

    This essay presents an alternative to the traditional view that ethics means judging individual behavior against standards of right and wrong. Instead, ethics is understood as creating ethical communities through the promises we make to each other. The "aim" of ethics is to demonstrate in our own behavior a credible willingness to work to create a mutually better world. The "game" of ethics then becomes searching for strategies that overlap with others' strategies so that we are all better for intending to act on a basis of reciprocal trust. This is a difficult process because we have partial, simultaneous, shifting, and inconsistent views of the world. But despite the reality that we each "frame" ethics in personal terms, it is still possible to create sufficient common understanding to prosper together. Large ethics does not make it a prerequisite for moral behavior that everyone adheres to a universally agreed set of ethical principles; all that is necessary is sufficient overlap in commitment to searching for better alternatives.

  1. Technical reference book for the Energy Economic Data Base Program (EEDB)

    International Nuclear Information System (INIS)

    1986-12-01

    This distribution is the latest in a series published since 1978. The overall program purpose is to provide periodically updated, detailed base construction cost estimates for large nuclear electric operating plants. These data, which are representative of current US powerplant construction cost experience, are a useful contribution to program planning by the Office of the Assistant Secretary for Nuclear Energy. The eighth update incorporates the results of a comprehensive update of the technical and cost information for the pressurized water reactor (PWR), large scale prototype breeder reactor nuclear powerplant (LSPB), and 488 MWe high sulfur, coal-fired powerplant (HS5) data models. During the Phase VIII update, the LSPB, which was first incorporated into the previous update, was brought into full conformance with EEDB ground rules, and the level of detail of the data models was extended to the EEDB fully detailed level. We remind the user that the LSPB must still be considered a second-of-a-kind, pre-commercial unit, and any comparisons of it with other EEDB data models should be carefully made recognizing dissimilarity achievement of design and cost maturity, particularly for the nuclear steam supply system and other equipment

  2. Advanced Control Systems for Aircraft Powerplants

    Science.gov (United States)

    1980-02-01

    should have some immediate visual effect. Hence for both psychological and practical reasons the ’GO’ placard was made to flash at about 1/4 sec...2i 1’cpar atar d’ ’n r arose ja rlevelurp_,rrnt su., las graupas A at R. Sorn funutiarnrmnt en tumbs r~E-i r ’aist pds a-jtcris(A p~ r I-i ’JL ,C

  3. Impact loading of a space nuclear powerplant

    Directory of Open Access Journals (Sweden)

    Evgeny I. Kraus

    2013-04-01

    Full Text Available Preferred formulation of the problem in two space dimensions are described for solving the three fundamental equations of mechanics (conservation of mass, conservation of momentum, and conservation of energy. Models of the behavior of materials provide the closure to the three fundamentals equations for applications to problems in compressible fluid flow and solid mechanics. Models of fracture and damage are described. A caloric model of the equation of state is proposed to describe thermodynamic properties of solid materials with the phase transitions. Two-dimensional problems of a high-velocity impact of a space nuclear propulsion system reactor are solved. High-velocity impact problems of destruction of reactor are solved for the two cases: 1 at its crash landing on the Earth surface (the impact velocity being up to 400 m/s; 2 at its impact (with velocity up to 16 km/s with the space debris fragments.

  4. Seismic design criteria for nuclear powerplants

    International Nuclear Information System (INIS)

    Jennings, P.C.; Guzman, R.A.

    1975-01-01

    There are three main aspects of the problem of selection of seismic design criteria for major projects such as nuclear power plants. These are the description of the appropriate level of shaking to be considered, usually given in the form of design spectra; the allowable response of the structure, usually specified in terms of allowable stresses and deflections; and the capability of the structure to dissipate energy, commonly given in the form of fractions of critical damping. In this presentation only the first of these features is examined, with particular application to nuclear power plants. Under these restrictions, the most important parts of the problem become the determination of the amplitude of the design spectra corresponding to the safe shutdown earthquake (SSE) and the question of whether the shape of the spectra recommended by Regulatory Guide 1.60 (U. S. Atomic Energy Commission, 1973) is appropriate for the particular application. In the course of working out the details of the approach, it was found useful to reexamine a number of concepts including the use of response spectra or peak values of ground motion parameters, the shape of the design spectra, problems in attenuation and scaling, and the use of motions on the ground surface or bedrock motions. There is nothing fundamentally new in the suggested approach, although some of the features may not have been applied to the problem of selecting design spectra for nuclear power plants in the way suggested. The approach is applied only to nuclear power plants but it is not limited to this application

  5. 1996 Portfolio of leading powerplants worldwide

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    This report covers activity in the electric power industry worldwide. The report is divided into three sections: Asia; Europe, Middle East, and Africa; and the Americas. The topics of the articles include major expansion programs for the primary power generating options, selected plant profiles; effect of the availability of natural gas on plans for coal-fired plants; and the pioneering of technologies in North America

  6. Opportunities for the power-plant industry

    International Nuclear Information System (INIS)

    Zeltmann, E.W.

    1992-01-01

    The author considers the major factors that will affect future demand for electricity in Europe, North America, Asia, Latin America, Africa and the Middle East. Worldwide growth in generating capacity in the next ten years is anticipated to be between 800 and 900 gigawatts, with the biggest growth rate being in Asia, and Europe requiring a quarter of the total worldwide additional capacity. The energy sources and technologies available to meet these demands are discussed. The author foresees a 'technology mix' with hydro and nuclear power contributing about one quarter of the additional capacity and systems based on gas or steam turbines contributing the remainder. Of the steam turbine based systems, basically burning coal in a boiler, an increasing share of coal-fueled generation will involve combined-cycle systems burning gasified coal. 5 figs

  7. Nuclear powerplant functions: quality assurance, construction

    International Nuclear Information System (INIS)

    Karpa, P.

    1984-01-01

    The author proposes that multilayer Quality Control is burdensome and ineffective. He proposes that the earlier approaches of having responsible field engineers back on the job site instead of at a home office be reinitiated to speed up necessary design changes and hold down costs. It is then the job of the quality control personnel to assure that the field engineer is doing his job. The idea of using the reactor start-up process as part of the quality assurance program is also proposed. Also discussed is the idea of Operating License Contracts or One Step Licensing Approach

  8. Nuclear powerplant design and issues of operation

    International Nuclear Information System (INIS)

    Howard, E.

    1984-01-01

    Various alternatives being looked at by electric utilities management considering additional or replacement nuclear power units are noted. Examples are sizing of units, service life extension of equipment, incremental capacity improvements, load management and pricing, robotics for reduction of occupational exposure, technical advances in water chemistry management and materials, information systems, reactor safety and emergency planning

  9. Behind the UK nuclear flip-flop

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Because it failed to attract commercial investors on acceptable terms, the British government has exempted the nation's nuclear powerplants from privatization, lopping off about 8,000 MW from National Power - the larger of the two successors to the broken-up Central Electricity Generating Board - and whipping up an antiprivatization political storm in the process. A new state company - to be called the Nuclear Electric Co - will be set up to control nuclear powerplants

  10. Instantons and Large N

    Science.gov (United States)

    Mariño, Marcos

    2015-09-01

    Preface; Part I. Instantons: 1. Instantons in quantum mechanics; 2. Unstable vacua in quantum field theory; 3. Large order behavior and Borel summability; 4. Non-perturbative aspects of Yang-Mills theories; 5. Instantons and fermions; Part II. Large N: 6. Sigma models at large N; 7. The 1=N expansion in QCD; 8. Matrix models and matrix quantum mechanics at large N; 9. Large N QCD in two dimensions; 10. Instantons at large N; Appendix A. Harmonic analysis on S3; Appendix B. Heat kernel and zeta functions; Appendix C. Effective action for large N sigma models; References; Author index; Subject index.

  11. Large Neighborhood Search

    DEFF Research Database (Denmark)

    Pisinger, David; Røpke, Stefan

    2010-01-01

    Heuristics based on large neighborhood search have recently shown outstanding results in solving various transportation and scheduling problems. Large neighborhood search methods explore a complex neighborhood by use of heuristics. Using large neighborhoods makes it possible to find better...... candidate solutions in each iteration and hence traverse a more promising search path. Starting from the large neighborhood search method,we give an overview of very large scale neighborhood search methods and discuss recent variants and extensions like variable depth search and adaptive large neighborhood...

  12. Large scale electrolysers

    International Nuclear Information System (INIS)

    B Bello; M Junker

    2006-01-01

    Hydrogen production by water electrolysis represents nearly 4 % of the world hydrogen production. Future development of hydrogen vehicles will require large quantities of hydrogen. Installation of large scale hydrogen production plants will be needed. In this context, development of low cost large scale electrolysers that could use 'clean power' seems necessary. ALPHEA HYDROGEN, an European network and center of expertise on hydrogen and fuel cells, has performed for its members a study in 2005 to evaluate the potential of large scale electrolysers to produce hydrogen in the future. The different electrolysis technologies were compared. Then, a state of art of the electrolysis modules currently available was made. A review of the large scale electrolysis plants that have been installed in the world was also realized. The main projects related to large scale electrolysis were also listed. Economy of large scale electrolysers has been discussed. The influence of energy prices on the hydrogen production cost by large scale electrolysis was evaluated. (authors)

  13. Large Pelagics Intercept Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Intercept Survey (LPIS) is a dockside survey of private and charterboat captains who have just completed fishing trips directed at large pelagic...

  14. The competitivity of nuclear electricity: the past and prospects

    International Nuclear Information System (INIS)

    Ferrari, A.; Bendell, F.

    1984-01-01

    This article attempts to answer the following questions: What has been the evolution during the past ten years of the costs of a kWh. Can the causes of this evolution be identified with certitude. Are costs now under control and are the present forecasts reliable. What is the situation concerning the competition between coal and nuclear energy [fr

  15. Nuclear Electrical and Optical Studies of Hydrogen in Semiconductors.

    CERN Multimedia

    Dietrich, M; Toulemonde, M

    2002-01-01

    During the last years, the understanding of H and its interaction with dopant atoms in Si, Ge and III-V semiconductors has improved considerably concerning the stability of the formed complexes their structural arrangements, and the implications of this interaction on the electrical properties of the semiconductors " passivation " The perturbed angular correlation technique (PAC) has contributed to the understanding of this phenomena on an atomistic scale using radioactive isotopes provided by ISOLDE. \\\\ \\\\The aim of the proposed experiments is twofold: \\\\ \\\\\\begin{enumerate} \\item The H passivation mechanism of acceptors in GaN and ternary III-V compounds (AlGaAs, GaInP, AlGaN) shall be investigated, using the PAC probe atom $^{111m}$Cd as a 'representative' of group II-B metal acceptors. The problems addressed in these technological important systems are microscopic structure, formation and stability of the hydrogen correlated complexes as function of doping and stoichiometry (i.e. the size of the band gap)...

  16. Reactor/Brayton power systems for nuclear electric spacecraft

    Science.gov (United States)

    Layton, J. P.

    1980-01-01

    Studies are currently underway to assess the technological feasibility of a nuclear-reactor-powered spacecraft propelled by electric thrusters. This vehicle would be capable of performing detailed exploration of the outer planets of the solar system during the remainder of this century. The purpose of this study was to provide comparative information on a closed cycle gas turbine power conversion system. The results have shown that the performance is very competitive and that a 400 kWe space power system is dimensionally compatible with a single Space Shuttle launch. Performance parameters of system mass and radiator area were determined for systems from 100 to 1000 kWe. A 400 kWe reference system received primary attention. The components of this system were defined and a conceptual layout was developed with encouraging results. The preliminary mass determination for the complete power system was very close to the desired goal of 20 kg/kWe. Use of more advanced technology (higher turbine inlet temperature) will substantially improve system performance characteristics.

  17. Nuclear electric quadrupole interactions in liquids entrapped in cavities

    Energy Technology Data Exchange (ETDEWEB)

    Furman, Gregory B., E-mail: gregoryf@bgu.ac.il; Meerovich, Victor M.; Sokolovsky, Vladimir L. [Ben Gurion University of the Negev, Physics Department (Israel)

    2016-12-15

    Liquids entrapped in cavities and containing quadrupole nuclei are considered. The interaction of the quadrupole moment of a nucleus with the electric field gradient is studied. In such a system, molecules are in both rotational and translational Brownian motions which are described by the diffusion equation. Solving this equation, we show that the intra- and intermolecular nuclear quadrupole interactions are averaged to zero in cavities with the size larger than several angstroms.

  18. PEGASUS: a multi-megawatt nuclear electric propulsion system

    International Nuclear Information System (INIS)

    Coomes, E.P.; Cuta, J.M.; Webb, B.J.; King, D.Q.

    1985-06-01

    With the Space Transportation System (STS), the advent of space station Columbus and the development of expertise at working in space that this will entail, the gateway is open to the final frontier. The exploration of this frontier is possible with state-of-the-art hydrogen/oxygen propulsion but would be greatly enhanced by the higher specific impulse of electric propulsion. This paper presents a concept that uses a multi-megawatt nuclear power plant to drive an electric propulsion system. The concept has been named PEGASUS, PowEr GenerAting System for Use in Space, and is intended as a ''work horse'' for general space transportation needs, both long- and short-haul missions. The recent efforts of the SP-100 program indicate that a power system capable of producing upwards of 1 megawatt of electric power should be available in the next decade. Additionally, efforts in other areas indicate that a power system with a constant power capability an order of magnitude greater could be available near the turn of the century. With the advances expected in megawatt-class space power systems, the high specific impulse propulsion systems must be reconsidered as potential propulsion systems. The power system is capable of meeting both the propulsion system and spacecraft power requirements

  19. Optimization of extended propulsion time nuclear-electric propulsion trajectories

    Science.gov (United States)

    Sauer, C. G., Jr.

    1981-01-01

    This paper presents the methodology used in optimizing extended propulsion time NEP missions considering realistic thruster lifetime constraints. These missions consist of a powered spiral escape from a 700-km circular orbit at the earth, followed by a powered heliocentric transfer with an optimized coast phase, and terminating in a spiral capture phase at the target planet. This analysis is most applicable to those missions with very high energy requirements such as outer planet orbiter missions or sample return missions where the total propulsion time could greatly exceed the expected lifetime of an individual thruster. This methodology has been applied to the investigation of NEP missions to the outer planets where examples are presented of both constrained and optimized trajectories.

  20. Power systems with nuclear-electric generators - Modelling methods

    International Nuclear Information System (INIS)

    Valeca, Serban Constantin

    2002-01-01

    This is a vast analysis on the issue of sustainable nuclear power development with direct conclusions regarding the Nuclear Programme of Romania. The work is targeting specialists and decision making boards. Specific to the nuclear power development is its public implication, the public being most often misinformed by non-professional media. The following problems are debated thoroughly: - safety, nuclear risk, respectively, is treated in chapter 1 and 7 aiming at highlighting the quality of nuclear power and consequently paving the way to public acceptance; - the environment considered both as resource of raw materials and medium essential for life continuation, which should be appropriately protected to ensure healthy and sustainable development of human society; its analysis is also presented in chapter 1 and 7, where the problem of safe management of radioactive waste is addressed too; - investigation methods based on information science of nuclear systems, applied in carrying out the nuclear strategy and planning are widely analyzed in the chapter 2, 3 and 6; - optimizing the processes by following up the structure of investment and operation costs, and, generally, the management of nuclear units is treated in the chapter 5 and 7; - nuclear weapon proliferation as a possible consequence of nuclear power generation is treated as a legal issue. The development of Romanian NPP at Cernavoda, practically, the core of the National Nuclear Programme, is described in chapter 8. Actually, the originality of the present work consists in the selection and adaptation from a multitude of mathematical models applicable to the local and specific conditions of nuclear power plant at Cernavoda. The Romanian economy development and power development oriented towards reduction of fossil fuel consumption and protection of environment, most reliably ensured by the nuclear power, is discussed in the frame of the world trends of the energy production. Various scenarios are considered. The author makes use of various predictive models, search-forecasting, catastrophic, chaotic and risk approaches to select the most suitable analytic apparatus applicable to the nuclear power plant at Cernavoda. Recognizing in costs the most the essential element in decision making the author stresses the current aspects of nuclear systems engineering and refurbishment, aiming at raising the cost-efficiency and competitiveness of the nuclear power systems. Management and personnel aspects are also reviewed. By taking Cernavoda NPP as a case study for CANDU type reactors the author has worked out a valuable methodology for following up nuclear power issue starting from investment, construction, operation and development

  1. Nuclear electric power and the proliferation of nuclear weapon states

    International Nuclear Information System (INIS)

    Walske, C.

    1977-01-01

    Control and elimination of the strategic nuclear weapons held by the nuclear weapon states remains the central problem in the arms control and disarmament field. Whether the proliferation of nations with nuclear weapons can be stopped is dubious. A sovereign nation will launch a nuclear weapons program if it has the motivation and resource. Motivation depends on military and political considerations. The necessary resources are economic and technological. Conditions in some sovereign states explain this issue. A survey of commercial nuclear power programs outside the USA lists 45 countries using or planning to use nuclear reactors for power generation. There are currently 112 reactors now operating outside the United States, 117 more under construction, 60 on order, and 180 planned. The U. S. as of December 1976 has 64 operating reactors, 72 under construction, 84 on order, and 8 planned. Nuclear trade and export policies are discussed. In this article, Mr. Walske says that American industry is convinced that the need for nuclear energy abroad is more urgent than in the United States; that in the long run, the breeder reactor must be developed to enable the supply of nuclear fuel to last for centuries; and that the experience of American industry abroad has convinced it that emphasis on restrictive, denial type policies will almost certainly fail--a collapse of what has been gained through the test ban treaty and the nonproliferation treaty

  2. Nuclear electricity for sustainable development: Egypt a case study

    Energy Technology Data Exchange (ETDEWEB)

    Comsan, M.N.H. [Projects and Consultation Unit, Afaq Scientific, 12 Qurash St., 6th Zone, Nasr City, Cairo 11371 (Egypt)

    2010-09-15

    Egypt is a fast growing country with 78.9 million population and annual per capita installed power 0.286 MW as of July 2008. Moderate to mature population and economic growth trends forecast population and annual per capita installed power to reach 111 millions and 0.63 MW, respectively by 2032; and 128 millions at per capita power of 1.02 MW by 2052. With these trends in consideration installed electricity generation capacity are forecasted at 70 GW by 2032 and 132 GW by 2052 as compared to the 2008 installed power of 22.6 GW. Meeting these demands is almost impossible using known limited national fossil fuel reserves. Current electricity generation policy exhausts about 65% of country's total fossil production. Crude oil reserves are expected to deplete by 2012, while gas reserves will be overstrained starting from 2030. A major policy shift towards the use of non-fossil resources is to be adopted. In the article Egypt's major primary energy resources are evaluated. Electricity generation plans till 2022 are presented and an electricity generation strategy based on gradual introduction of nuclear power starting from 2018 is outlined. A balanced generation mix based on 72.7% fossil, 13% nuclear and 14.3% renewables is targeted by 2052. The mix is supposed to meet Egypt's electricity needs by 2052 and to improve country's energy sustainability. (author)

  3. Renewable and nuclear electricity: Comparison of environmental impacts

    International Nuclear Information System (INIS)

    McCombie, Charles; Jefferson, Michael

    2016-01-01

    Given the widely acknowledged negative impacts of fossil fuels, both on human health and on potential climate change, it is of interest to compare the impacts of low carbon alternative energy sources such as nuclear energy, hydropower, solar, wind and biomass. In this paper, we review the literature in order to summarise the impacts of the different technologies in terms of their materials and energy requirements, their emissions during operation, their health effects during operation, the accident risks, and the associated waste streams. We follow up these comparisons with some more anecdotal evidence on selected impacts that are either particularly topical or are important but less commonly addressed. These include impacts of wind turbines on persons and on bird life, the underestimated problems with biomass, and concerns about biodiversity reduction. Finally we address the public attitudes towards both renewable energy technologies and to nuclear power. The conclusion is drawn that energy policies of many countries are perhaps more strongly influenced by public and political perceptions of available technologies than they are by rational assessment of the actual benefits and drawbacks. Policy recommendations follow from this conclusion. - Highlights: •Given the acknowledged hazards of fossil fuels, it is important to compare the impacts of low-carbon alternatives. •This report reviews published data to compare nuclear with hydro, wind, solar and biomass electricity production. •Environmental impacts and risks to humans are compared. •Specific impacts of wind turbines on bird populations are examined. •Conclusions and recommendations for future energy choices are presented.

  4. Nuclear electric power plants. [Journal, in Russian]. Atomnye elektricheskie stantsii

    Energy Technology Data Exchange (ETDEWEB)

    Voronin, L M [ed.

    1980-01-01

    Separate articles are concerned with experience gained in the planning, exploitation, and adjustment of nuclear power plants with channel reactors. An examination is made of measures to be taken for assuring equipment reliability for nuclear power plants during the planning stage. Also examined is the experience gained in the operation of the pilot plants of the Kursk and Chernobyl' nuclear power plants, and the Bilibin nuclear thermal electric power plant. Considerable attention is given to the reprocessing and disposal of radioactive waste, the quality control of metal ducts in nuclear power plants, and the development of methods and means of controlling technological processes and equipment. The journal is intended for engineering-technical personnel of power plants, power supply administrations, adjustment, repair, and planning organizations.

  5. The Church, too, is to pay for 'nuclear electricity'

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The Regional Court (LG) of Essen in an appeal lodged by the plaintiff (electric utility company) against a protestant parish for payment of electricity rates retained (10 per cent) and for further declaration of the defendant's obligation to pay, by ruling dated September 30, 1981 - 15 S 136/81 - has modified the decree issued at first instance by the District Court (AG) of Gelsenkirchen on March 30, 81, to the effect that the defendant has the obligation to pay also in future to the plaintiff without curtailment such electricity rates and advance payments as will be invoiced by the latter in accordance with the power supply contracts concluded between plaintiff and defendant in writing in connection with the general conditions governing the supply of electric power from the low-voltage power supply systems, and also if the plaintiff should continue to provide the defendant with electric power generated by nuclear power plants'. The defendant was not adjudged the right to refuse payment on grounds of conscience. (orig./HP) [de

  6. CENTRAL NUCLEAR ELECTRIC, A FUTURE OF ROMANIAN ENERGY

    Directory of Open Access Journals (Sweden)

    Gabriel I. NĂSTASE

    2010-05-01

    Full Text Available Official statistics show the year increasing the share of electricity produced in nuclear power plants. The most developed nuclear energy programs are: the United States, France, Japan, Germany and Canada. Although Romania was among the first countries in Eastern Europe that had a nuclear research program, switching to nuclear power reactors has been extremely difficult and slow. The implications of this decisionmaking process were the first political and then economic. There were a series of oscillations between Wer system offered by the USSR and the CANDU-PHWR supplied by Canada. Considering nuclear reactors Wer insufficiently protected against a nuclear accident, and the total requested by the former Soviet Union on the nuclear fuel cycle, the decision of us have opted for CANDU reactor, fueled with natural uranium, moderated and cooled with heavy water.

  7. Renewal of nuclear electricity production: an economic trend

    International Nuclear Information System (INIS)

    Debontride, B.; Bouteille, F.; Goebel, A.; Czech, J.

    2004-01-01

    2004 price evolution on the market asks on nuclear generation profitability and competitiveness. There were over installed capacities in Europe since several years, but electricity consumption is steadily increasing and over capacities will disappear more or less at the end of the decade. On a world basis, electricity demand grows twice as much as energy demand, so that there is a need to invest in new electricity generation capacities. The recent US black out events shows the need for securing energy supply in capacities as well as in transmission and distribution. Competitiveness of the different possible sources of energy thus needs to be carefully assessed by all the worldwide decision makers in the field of power generation. In France, the economy of the electricity production is regularly assessed by a French Government study called 'Reference costs for Electricity production' which compares the levelized cost for base load power produced by a nuclear unit (latest design available) and other conventional power stations. In the latest release published in 2003 the nuclear option (the EPR) is compared with three fossil-fired units: A twin 400 MW combined-cycle gas plant, a twin 900 MW pulverized coal station and a 400 MW fluidized bed combustion coal plant. In all cases the nuclear option is the cheapest. If external costs, based on the EU studies (ExternE), are taken into account, the advantage of the nuclear option is significantly increased. In Finland a study performed by the Lappeenranta University in 2000 concluded also in the competitiveness of the Nuclear option. This result was important in the decision making process which resulted in the decision in principle of the Finnish Parliament to allow for the construction of the fifth Nuclear power station for which the EPR was selected. In China, the same kind of economical studies recently led the governmental authorities to launch new nuclear projects. These three examples, in three countries where political decision makers have recently confirmed the need to rely on the nuclear option, show that the situation is changing in Europe and more generally in the world. The paper will discuss this new context. (author)

  8. Social and economic impact of nuclear electricity in Britain

    International Nuclear Information System (INIS)

    White, D.

    1985-01-01

    The paper concerns a study of the social and economic impact of nuclear energy in the U.K., undertaken by an independent writer. Fears and risks; nuclear power is proven; cost comparisons; the nuclear industry; social impact and public relations; are all discussed. (U.K.)

  9. Production of concentrates for supplying a national nuclear electric program

    International Nuclear Information System (INIS)

    Delgado, C.M.

    An analysis was made of the yearly requirements of natural U to satisfy a nuclear power program in Mexico. On the basis of these requirements an evaluation was made of the concentrate production necessary to supply those needs. The lack of known commercial reserves to satisfy the concentrate needs is shown. An estimation is made of the costs for the discovery and exploitation of sufficient reserves. In evaluating the U needs and associated costs, three cases were considered: all BWR or PWR or HWR

  10. The Spanish Nuclear Electricity Generating Capacity since 1982

    International Nuclear Information System (INIS)

    Garcia de Ubieta, A.

    2000-01-01

    The article describes the evolution of Spain's nuclear power plants since 1982, the year in which the journal of the Spanish Nuclear Society first appeared, underlining those events that have had a special impact on this evolution at national and international level. At present, there are 9 nuclear groups operating in the country, of the total 17 that were at different stages of their life cycle at that time. This reduction in the number of groups that finally managed to initiated and indefinitely continue their operating lifetime contrasts with the growth of electricity consumption over the period, which has practically doubled. During these 18 years have been profound transformations in the social, economic and political context of Spain, both in general and in the Electricity Industry in particular. Nevertheless, there are now reasons, old new, to feel confident as regards the future of this energy source. (Author)

  11. US central station nuclear electric generating units: significant milestones

    International Nuclear Information System (INIS)

    1979-09-01

    Listings of US nuclear power plants include significant dates, reactor type, owners, and net generating capacity. Listings are made by state, region, and utility. Tabulations of status, schedules, and orders are also presented

  12. Nuclear electric dipole moments in chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Bsaisou, J.; Vries, J. de [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Hanhart, C. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany); Liebig, S. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Meißner, Ulf-G. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - High Performance Computing,Forschungszentrum Jülich, D-52425 Jülich (Germany); Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics,Universität Bonn,D-53115 Bonn (Germany); Minossi, D. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Nogga, A.; Wirzba, A. [Institute for Advanced Simulation, Institut für Kernphysik, and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - Forces and Matter Experiments,Forschungszentrum Jülich, D-52425 Jülich (Germany)

    2015-03-19

    We provide a consistent and complete calculation of the electric dipole moments of the deuteron, helion, and triton in the framework of chiral effective field theory. The CP-conserving and CP-violating interactions are treated on equal footing and we consider CP-violating one-, two-, and three-nucleon operators up to next-to-leading-order in the chiral power counting. In particular, we calculate for the first time EDM contributions induced by the CP-violating three-pion operator. We find that effects of CP-violating nucleon-nucleon contact interactions are larger than those found in previous studies based on phenomenological models for the CP-conserving nucleon-nucleon interactions. Our results which apply to any model of CP violation in the hadronic sector can be used to test various scenarios of CP violation. As examples, we study the implications of our results on the QCD θ-term and the minimal left-right symmetric model.

  13. Proposal of space reactor for nuclear electric propulsion system

    International Nuclear Information System (INIS)

    Nishiyama, Takaaki; Nagata, Hidetaka; Nakashima, Hideki

    2009-01-01

    A nuclear reactor installed in spacecrafts is considered here. The nuclear reactor could stably provide an enough amount of electric power in deep space missions. Most of the nuclear reactors that have been developed up to now in the United States and the former Soviet Union have used uranium with 90% enrichment of 235 U as a fuel. On the other hand, in Japan, because the uranium that can be used is enriched to below 20%, the miniaturization of the reactor core is difficult. A Light-water nuclear reactor is an exception that could make the reactor core small. Then, the reactor core composition and characteristic are evaluated for the cases with the enrichment of the uranium fuel as 20%. We take up here Graphite reactor, Light-water reactor, and Sodium-cooled one. (author)

  14. The cost of nuclear electricity: economic values and political calculations

    International Nuclear Information System (INIS)

    Stauffer, T.

    1985-01-01

    The subject is covered in sections: introduction (monetary inflation; US-style rate-base formula; cost escalation); electricity generation costs (rate-base calculation formula; regulatory versus economic costs; inflationary case; cost-of-service rates versus inflation; first year electricity costs); rate shock (A. comparison with oil; B. nuclear case; C. comparison with coal/nuclear system; vintaged electricity costs versus growth and inflation); conclusions. (U.K.)

  15. Large electrostatic accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1984-01-01

    The paper is divided into four parts: a discussion of the motivation for the construction of large electrostatic accelerators, a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year

  16. Large mass storage facility

    International Nuclear Information System (INIS)

    Peskin, A.M.

    1978-01-01

    The report of a committee to study the questions surrounding possible acquisition of a large mass-storage device is presented. The current computing environment at BNL and justification for an online large mass storage device are briefly discussed. Possible devices to meet the requirements of large mass storage are surveyed, including future devices. The future computing needs of BNL are prognosticated. 2 figures, 4 tables

  17. Large N Scalars

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2016-01-01

    We construct effective Lagrangians, and corresponding counting schemes, valid to describe the dynamics of the lowest lying large N stable massive composite state emerging in strongly coupled theories. The large N counting rules can now be employed when computing quantum corrections via an effective...

  18. Large bowel resection

    Science.gov (United States)

    ... blockage in the intestine due to scar tissue Colon cancer Diverticular disease (disease of the large bowel) Other reasons for bowel resection are: Familial polyposis (polyps are growths on the lining of the colon or rectum) Injuries that damage the large bowel ...

  19. Adaptive Large Neighbourhood Search

    DEFF Research Database (Denmark)

    Røpke, Stefan

    Large neighborhood search is a metaheuristic that has gained popularity in recent years. The heuristic repeatedly moves from solution to solution by first partially destroying the solution and then repairing it. The best solution observed during this search is presented as the final solution....... This tutorial introduces the large neighborhood search metaheuristic and the variant adaptive large neighborhood search that dynamically tunes parameters of the heuristic while it is running. Both heuristics belong to a broader class of heuristics that are searching a solution space using very large...... neighborhoods. The tutorial also present applications of the adaptive large neighborhood search, mostly related to vehicle routing problems for which the heuristic has been extremely successful. We discuss how the heuristic can be parallelized and thereby take advantage of modern desktop computers...

  20. EPRI nuclear fuel-cycle accident risk assessment

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    The present results of the nuclear fuel-cycle accident risk assessment conducted by the Electric Power Research Institute show that the total risk contribution of the nuclear fuel cycle is only approx. 1% of the accident risk of the power plant; hence, with little error, the accident risk of nuclear electric power is essentially that of the power plant itself. The power-plant risk, assuming a very large usage of nuclear power by the year 2005 is only approx. 0.5% of the radiological risk of natural background. The smallness of the fuel-cycle risk relative to the power-plant risk may be attributed to the lack of internal energy to drive an accident and the small amount of dispersible material. This work aims at a realistic assessment of the process hazards, the effectiveness of confinement and mitigation systems and procedures, and the associated likelihood of errors and the estimated size of errors. The primary probabilistic estimation tool is fault-tree analysis, with the release source terms calculated using physicochemical processes. Doses and health effects are calculated with CRAC (Consequences of Reactor Accident Code). No evacuation or mitigation is considered; source terms may be conservative through the assumption of high fuel burnup (40,000 MWd/t) and short cooling period (90 to 150 d); high-efficiency particulate air filter efficiencies are derived from experiments

  1. ERP inside Large Organizations

    Directory of Open Access Journals (Sweden)

    Constantin Daniel AVRAM

    2010-01-01

    Full Text Available Many large companies in Romania are still functioning without an ERP system. Instead they are using traditional application systems built around the strong boundaries of specific functions: finance, selling, HR, production. An ERP will offer lots of advantages among which the integration of functionalities and support for top management decisions. Although the total cost of ownership is not small and there are some risks when implementing an ERP inside large and very large organizations, having such a system is mandatory. Choosing the right product and vendor and using a correct risk management strategy, will ensure a successful implementation.

  2. Large Pelagics Telephone Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Telephone Survey (LPTS) collects fishing effort information directly from captains holding Highly Migratory Species (HMS) permits (required by...

  3. Large Customers (DR Sellers)

    Energy Technology Data Exchange (ETDEWEB)

    Kiliccot, Sila [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2011-10-25

    State of the large customers for demand response integration of solar and wind into electric grid; openADR; CAISO; DR as a pseudo generation; commercial and industrial DR strategies; California regulations

  4. Large Pelagics Biological Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Biological Survey (LPBS) collects additional length and weight information and body parts such as otoliths, caudal vertebrae, dorsal spines, and...

  5. Large Rotor Test Apparatus

    Data.gov (United States)

    Federal Laboratory Consortium — This test apparatus, when combined with the National Full-Scale Aerodynamics Complex, produces a thorough, full-scale test capability. The Large Rotor Test Apparatus...

  6. Large transverse momentum phenomena

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1977-09-01

    It is pointed out that it is particularly significant that the quantum numbers of the leading particles are strongly correlated with the quantum numbers of the incident hadrons indicating that the valence quarks themselves are transferred to large p/sub t/. The crucial question is how they get there. Various hadron reactions are discussed covering the structure of exclusive reactions, inclusive reactions, normalization of inclusive cross sections, charge correlations, and jet production at large transverse momentum. 46 references

  7. Large Retailers’ Financial Services

    OpenAIRE

    Risso, Mario

    2010-01-01

    Over the last few years, large retailers offering financial services have considerably grown in the financial services sector. Retailers are increasing the wideness and complexity of their offer of financial services. Large retail companies provide financial services to their customers following different strategic ways. The provision of financial services in the retailers offer is implemented in several different ways related to the strategies, the structures and the degree of financial know...

  8. Large momentum transfer phenomena

    International Nuclear Information System (INIS)

    Imachi, Masahiro; Otsuki, Shoichiro; Matsuoka, Takeo; Sawada, Shoji.

    1978-01-01

    The large momentum transfer phenomena in hadron reaction drastically differ from small momentum transfer phenomena, and are described in this paper. Brief review on the features of the large transverse momentum transfer reactions is described in relation with two-body reactions, single particle productions, particle ratios, two jet structure, two particle correlations, jet production cross section, and the component of momentum perpendicular to the plane defined by the incident protons and the triggered pions and transverse momentum relative to jet axis. In case of two-body process, the exponent N of the power law of the differential cross section is a value between 10 to 11.5 in the large momentum transfer region. The breaks of the exponential behaviors into the power ones are observed at the large momentum transfer region. The break would enable to estimate the order of a critical length. The large momentum transfer phenomena strongly suggest an important role of constituents of hadrons in the hard region. Hard rearrangement of constituents from different initial hadrons induces large momentum transfer reactions. Several rules to count constituents in the hard region have been proposed so far to explain the power behavior. Scale invariant quark interaction and hard reactions are explained, and a summary of the possible types of hard subprocess is presented. (Kato, T.)

  9. Large electrostatic accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Jones, C.M.

    1984-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of large electrostatic accelerators designed to operate at terminal potentials of 20 MV or above. In this paper, the author briefly discusses the status of these new accelerators and also discusses several recent technological advances which may be expected to further improve their performance. The paper is divided into four parts: (1) a discussion of the motivation for the construction of large electrostatic accelerators, (2) a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, (3) a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and (4) a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year. Due to time and space constraints, discussion is restricted to consideration of only tandem accelerators.

  10. Large electrostatic accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1984-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of large electrostatic accelerators designed to operate at terminal potentials of 20 MV or above. In this paper, the author briefly discusses the status of these new accelerators and also discusses several recent technological advances which may be expected to further improve their performance. The paper is divided into four parts: (1) a discussion of the motivation for the construction of large electrostatic accelerators, (2) a description and discussion of several large electrostatic accelerators which have been recently completed or are under construction, (3) a description of several recent innovations which may be expected to improve the performance of large electrostatic accelerators in the future, and (4) a description of an innovative new large electrostatic accelerator whose construction is scheduled to begin next year. Due to time and space constraints, discussion is restricted to consideration of only tandem accelerators

  11. Report on the behalf of the inquiry commission related to past, present and future costs of the nuclear sector, to the reactor exploitation duration, and to various economic and financial aspects of production and commercialization of nuclear electricity within the frame of the French and European electric mix, as well as to the consequences of the shutting down and dismantling of nuclear reactors, notably the Fessenheim power plant - Nr 2007

    International Nuclear Information System (INIS)

    Brottes, Francois; Baupin, Denis

    2014-01-01

    This official report first describes the role of nuclear energy in the European electric system: economic context (pricing mode, interconnection leading to a European price), similar situations and different policies in Germany, Belgium and UK. It proposes the contribution of the inquiry commission: a constrained energy transition, a shared diagnosis on the status of the European electric system but two possible solutions, nuclear as an economy on its own requiring a strong commitment of public authorities. The next part addresses the front end of the nuclear cycle, i.e. how to ensure the supply of the French nuclear fleet (world resources, demand-supply balance, weak relationship between uranium price and nuclear electricity price). The inquiry commission outlines and discusses the roles of AREVA for the front end, EDF which tries to be less vulnerable, and the State (EDF's regulator and Areva's support). The third part addresses the maintenance and subcontracting expenses: maintenance as a major challenge to control costs, subcontracting as a choice of industrial policy. The inquiry commission notices that EDF has not yet reached a full control of maintenance and that subcontracting remains a matter of controversy. The fourth part discusses the fleet evolution: entry in the fourth decade, a life extension project which requires safety improvement. The inquiry commission discusses the numerous uncertainties of the industrial project, outlines that the construction of a new fleet requires huge investments, that the future of the nuclear fleet requires a global approach, and that shutting down nuclear plants requires support. The fifth part discusses the correct assessment of the amount of future expenses and how to secure their funding: the main future expenses are those related to installation dismantling and to nuclear wastes. The inquiry commission outlines the uncertainties about this funding. The sixth chapter addresses reprocessing activities, MOX fuel and

  12. Large field radiotherapy

    International Nuclear Information System (INIS)

    Vanasek, J.; Chvojka, Z.; Zouhar, M.

    1984-01-01

    Calculations may prove that irradiation procedures, commonly used in radiotherapy and represented by large-capacity irradiation techniques, do not exceed certain limits of integral doses with favourable radiobiological action on the organism. On the other hand integral doses in supralethal whole-body irradiation, used in the therapy of acute leukemia, represent radiobiological values which without extreme and exceptional further interventions and teamwork are not compatible with life, and the radiotherapeutist cannot use such high doses without the backing of a large team. (author)

  13. Developing Large Web Applications

    CERN Document Server

    Loudon, Kyle

    2010-01-01

    How do you create a mission-critical site that provides exceptional performance while remaining flexible, adaptable, and reliable 24/7? Written by the manager of a UI group at Yahoo!, Developing Large Web Applications offers practical steps for building rock-solid applications that remain effective even as you add features, functions, and users. You'll learn how to develop large web applications with the extreme precision required for other types of software. Avoid common coding and maintenance headaches as small websites add more pages, more code, and more programmersGet comprehensive soluti

  14. Choice of large projects

    Energy Technology Data Exchange (ETDEWEB)

    Harris, R

    1978-08-01

    Conventional cost/benefit or project analysis has generally not taken into account circumstances in which the project under consideration is large enough that its introduction to the economy would have significant general equilibrium effects. In this paper, rules are examined that would indicate whether such large projects should be accepted or rejected. The rules utilize information yielded by before-project and after-project equilibrium prices and production data. Rules are developed for the undistorted ''first-best'' case, the case in which the fixed costs of the project are covered by distortionary taxation, and for the case of projects producing public goods. 34 references.

  15. Licensing process at Grand Gulf Nuclear Powerplant. Oversight hearing before the Subcommittee on Energy and the Environment of the Committee on Interior and Insular Affairs, House of Representatives, Ninety-Eighth Congress, Second Session, July 24, 1984

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    A panel of Commissioners from the Nuclear Regulatory Commission (NRC) headed by Nunzio Palladino and a panel of witnesses from the Jacksonians United for Livable Energy Policies and the Union of Concerned Scientists testified at a hearing on licensing of the Grand Gulf nuclear plant for low-power operation and the reasons for delaying its application for full-power licensing. At issue were a number of irregularities during the design and construction stages and the integrity of the regulatory systems. Panelists were asked to limit their comments to licensing procedures, and not to debate safety issues. Witnesses were critical of NRC's handling of the licensing in view of the large number of errors, unqualified personnel, mishaps, and other problems which have plagued the plant. An appendix with additional material from the witnesses and others follows the testimony

  16. LARGE SCALE GLAZED

    DEFF Research Database (Denmark)

    Bache, Anja Margrethe

    2010-01-01

    OF SELECTED EXISTING BUILDINGS IN AND AROUND COPENHAGEN COVERED WITH MOSAIC TILES, UNGLAZED OR GLAZED CLAY TILES. ITS BUILDINGS WHICH HAVE QUALITIES THAT I WOULD LIKE APPLIED, PERHAPS TRANSFORMED OR MOST PREFERABLY, INTERPRETED ANEW, FOR THE LARGE GLAZED CONCRETE PANELS I AM DEVELOPING. KEYWORDS: COLOR, LIGHT...

  17. Large hydropower generating units

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    This document presents the Brazilian experience with the design, fabrication, construction, commissioning and operation of large scale and generation capacity unities. The experience had been acquired with the implementation of Itumbiara, Paulo Afonso IV, Tucurui, Itaipu and Xingo power plants, which are among the largest world unities.

  18. Large Data Set Mining

    NARCIS (Netherlands)

    Leemans, I.B.; Broomhall, Susan

    2017-01-01

    Digital emotion research has yet to make history. Until now large data set mining has not been a very active field of research in early modern emotion studies. This is indeed surprising since first, the early modern field has such rich, copyright-free, digitized data sets and second, emotion studies

  19. Representing Large Virtual Worlds

    NARCIS (Netherlands)

    Kol, T.R.

    2018-01-01

    The ubiquity of large virtual worlds and their growing complexity in computer graphics require efficient representations. This means that we need smart solutions for the underlying storage of these complex environments, but also for their visualization. How the virtual world is best stored and how

  20. The large hadron computer

    CERN Multimedia

    Hirstius, Andreas

    2008-01-01

    Plans for dealing with the torrent of data from the Large Hadron Collider's detectors have made the CERN particle-phycis lab, yet again, a pioneer in computing as well as physics. The author describes the challenges of processing and storing data in the age of petabyt science. (4 pages)

  1. LARGE BUILDING HVAC SIMULATION

    Science.gov (United States)

    The report discusses the monitoring and collection of data relating to indoor pressures and radon concentrations under several test conditions in a large school building in Bartow, Florida. The Florida Solar Energy Center (FSEC) used an integrated computational software, FSEC 3.0...

  2. Large Hadron Collider

    CERN Multimedia

    2007-01-01

    "In the spring 2008, the Large Hadron Collider (LHC) machine at CERN (the European Particle Physics laboratory) will be switched on for the first time. The huge machine is housed in a circular tunnel, 27 km long, excavated deep under the French-Swiss border near Geneva." (1,5 page)

  3. Large reservoirs: Chapter 17

    Science.gov (United States)

    Miranda, Leandro E.; Bettoli, Phillip William

    2010-01-01

    Large impoundments, defined as those with surface area of 200 ha or greater, are relatively new aquatic ecosystems in the global landscape. They represent important economic and environmental resources that provide benefits such as flood control, hydropower generation, navigation, water supply, commercial and recreational fisheries, and various other recreational and esthetic values. Construction of large impoundments was initially driven by economic needs, and ecological consequences received little consideration. However, in recent decades environmental issues have come to the forefront. In the closing decades of the 20th century societal values began to shift, especially in the developed world. Society is no longer willing to accept environmental damage as an inevitable consequence of human development, and it is now recognized that continued environmental degradation is unsustainable. Consequently, construction of large reservoirs has virtually stopped in North America. Nevertheless, in other parts of the world construction of large reservoirs continues. The emergence of systematic reservoir management in the early 20th century was guided by concepts developed for natural lakes (Miranda 1996). However, we now recognize that reservoirs are different and that reservoirs are not independent aquatic systems inasmuch as they are connected to upstream rivers and streams, the downstream river, other reservoirs in the basin, and the watershed. Reservoir systems exhibit longitudinal patterns both within and among reservoirs. Reservoirs are typically arranged sequentially as elements of an interacting network, filter water collected throughout their watersheds, and form a mosaic of predictable patterns. Traditional approaches to fisheries management such as stocking, regulating harvest, and in-lake habitat management do not always produce desired effects in reservoirs. As a result, managers may expend resources with little benefit to either fish or fishing. Some locally

  4. Large Hadron Collider manual

    CERN Document Server

    Lavender, Gemma

    2018-01-01

    What is the universe made of? How did it start? This Manual tells the story of how physicists are seeking answers to these questions using the world’s largest particle smasher – the Large Hadron Collider – at the CERN laboratory on the Franco-Swiss border. Beginning with the first tentative steps taken to build the machine, the digestible text, supported by color photographs of the hardware involved, along with annotated schematic diagrams of the physics experiments, covers the particle accelerator’s greatest discoveries – from both the perspective of the writer and the scientists who work there. The Large Hadron Collider Manual is a full, comprehensive guide to the most famous, record-breaking physics experiment in the world, which continues to capture the public imagination as it provides new insight into the fundamental laws of nature.

  5. [Large benign prostatic hiperplasia].

    Science.gov (United States)

    Soria-Fernández, Guillermo René; Jungfermann-Guzman, José René; Lomelín-Ramos, José Pedro; Jaspersen-Gastelum, Jorge; Rosas-Nava, Jesús Emmanuel

    2012-01-01

    the term prostatic hyperplasia is most frequently used to describe the benign prostatic growth, this being a widely prevalent disorder associated with age that affects most men as they age. The association between prostate growth and urinary obstruction in older adults is well documented. large benign prostatic hyperplasia is rare and few cases have been published and should be taken into account during the study of tumors of the pelvic cavity. we report the case of an 81-year-old who had significant symptoms relating to storage and bladder emptying, with no significant elevation of prostate specific antigen. this is a rare condition but it is still important to diagnose and treat as it may be related to severe obstructive uropathy and chronic renal failure. In our institution, cases of large prostatic hyperplasia that are solved by suprapubic adenomectomy are less than 3%.

  6. [Large vessel vasculitides].

    Science.gov (United States)

    Morović-Vergles, Jadranka; Puksić, Silva; Gracanin, Ana Gudelj

    2013-01-01

    Large vessel vasculitis includes Giant cell arteritis and Takayasu arteritis. Giant cell arteritis is the most common form of vasculitis affect patients aged 50 years or over. The diagnosis should be considered in older patients who present with new onset of headache, visual disturbance, polymyalgia rheumatica and/or fever unknown cause. Glucocorticoides remain the cornerstone of therapy. Takayasu arteritis is a chronic panarteritis of the aorta ant its major branches presenting commonly in young ages. Although all large arteries can be affected, the aorta, subclavian and carotid arteries are most commonly involved. The most common symptoms included upper extremity claudication, hypertension, pain over the carotid arteries (carotidynia), dizziness and visual disturbances. Early diagnosis and treatment has improved the outcome in patients with TA.

  7. Large tandem accelerators

    International Nuclear Information System (INIS)

    Jones, C.M.

    1976-01-01

    The increasing importance of energetic heavy ion beams in the study of atomic physics, nuclear physics, and materials science has partially or wholly motivated the construction of a new generation of tandem accelerators designed to operate at maximum terminal potentials in the range 14 to 30 MV. In addition, a number of older tandem accelerators are now being significantly upgraded to improve their heavy ion performance. Both of these developments have reemphasized the importance of negative heavy ion sources. The new large tandem accelerators are described, and the requirements placed on negative heavy ion source technology by these and other tandem accelerators used for the acceleration of heavy ions are discussed. First, a brief description is given of the large tandem accelerators which have been completed recently, are under construction, or are funded for construction, second, the motivation for construction of these accelerators is discussed, and last, criteria for negative ion sources for use with these accelerators are presented

  8. Large scale reflood test

    International Nuclear Information System (INIS)

    Hirano, Kemmei; Murao, Yoshio

    1980-01-01

    The large-scale reflood test with a view to ensuring the safety of light water reactors was started in fiscal 1976 based on the special account act for power source development promotion measures by the entrustment from the Science and Technology Agency. Thereafter, to establish the safety of PWRs in loss-of-coolant accidents by joint international efforts, the Japan-West Germany-U.S. research cooperation program was started in April, 1980. Thereupon, the large-scale reflood test is now included in this program. It consists of two tests using a cylindrical core testing apparatus for examining the overall system effect and a plate core testing apparatus for testing individual effects. Each apparatus is composed of the mock-ups of pressure vessel, primary loop, containment vessel and ECCS. The testing method, the test results and the research cooperation program are described. (J.P.N.)

  9. Large scale model testing

    International Nuclear Information System (INIS)

    Brumovsky, M.; Filip, R.; Polachova, H.; Stepanek, S.

    1989-01-01

    Fracture mechanics and fatigue calculations for WWER reactor pressure vessels were checked by large scale model testing performed using large testing machine ZZ 8000 (with a maximum load of 80 MN) at the SKODA WORKS. The results are described from testing the material resistance to fracture (non-ductile). The testing included the base materials and welded joints. The rated specimen thickness was 150 mm with defects of a depth between 15 and 100 mm. The results are also presented of nozzles of 850 mm inner diameter in a scale of 1:3; static, cyclic, and dynamic tests were performed without and with surface defects (15, 30 and 45 mm deep). During cyclic tests the crack growth rate in the elastic-plastic region was also determined. (author). 6 figs., 2 tabs., 5 refs

  10. Large mass storage facility

    Energy Technology Data Exchange (ETDEWEB)

    Peskin, Arnold M.

    1978-08-01

    This is the final report of a study group organized to investigate questions surrounding the acquisition of a large mass storage facility. The programatic justification for such a system at Brookhaven is reviewed. Several candidate commercial products are identified and discussed. A draft of a procurement specification is developed. Some thoughts on possible new directions for computing at Brookhaven are also offered, although this topic was addressed outside of the context of the group's deliberations. 2 figures, 3 tables.

  11. The Large Hadron Collider

    CERN Document Server

    Juettner Fernandes, Bonnie

    2014-01-01

    What really happened during the Big Bang? Why did matter form? Why do particles have mass? To answer these questions, scientists and engineers have worked together to build the largest and most powerful particle accelerator in the world: the Large Hadron Collider. Includes glossary, websites, and bibliography for further reading. Perfect for STEM connections. Aligns to the Common Core State Standards for Language Arts. Teachers' Notes available online.

  12. Large Right Pleural Effusion

    Directory of Open Access Journals (Sweden)

    Robert Rowe

    2016-09-01

    Full Text Available History of present illness: An 83-year-old male with a distant history of tuberculosis status post treatment and resection approximately fifty years prior presented with two days of worsening shortness of breath. He denied any chest pain, and reported his shortness of breath was worse with exertion and lying flat. Significant findings: Chest x-ray and bedside ultrasound revealed a large right pleural effusion, estimated to be greater than two and a half liters in size. Discussion: The incidence of pleural effusion is estimated to be at least 1.5 million cases annually in the United States.1 Erect posteroanterior and lateral chest radiography remains the mainstay for diagnosis of a pleural effusion; on upright chest radiography small effusions (>400cc will blunt the costophrenic angles, and as the size of an effusion grows it will begin to obscure the hemidiphragm.1 Large effusions will cause mediastinal shift away from the affected side (seen in effusions >1000cc.1 Lateral decubitus chest radiography can detect effusions greater than 50cc.1 Ultrasonography can help differentiate large pulmonary masses from effusions and can be instrumental in guiding thoracentesis.1 The patient above was comfortable at rest and was admitted for a non-emergent thoracentesis. The pulmonology team removed 2500cc of fluid, and unfortunately the patient subsequently developed re-expansion pulmonary edema and pneumothorax ex-vacuo. It is generally recommended that no more than 1500cc be removed to minimize the risk of re-expansion pulmonary edema.2

  13. Large litter sizes

    DEFF Research Database (Denmark)

    Sandøe, Peter; Rutherford, K.M.D.; Berg, Peer

    2012-01-01

    This paper presents some key results and conclusions from a review (Rutherford et al. 2011) undertaken regarding the ethical and welfare implications of breeding for large litter size in the domestic pig and about different ways of dealing with these implications. Focus is primarily on the direct...... possible to achieve a drop in relative piglet mortality and the related welfare problems. However, there will be a growing problem with the need to use foster or nurse sows which may have negative effects on both sows and piglets. This gives rise to new challenges for management....

  14. Large lithium loop experience

    International Nuclear Information System (INIS)

    Kolowith, R.; Owen, T.J.; Berg, J.D.; Atwood, J.M.

    1981-10-01

    An engineering design and operating experience of a large, isothermal, lithium-coolant test loop are presented. This liquid metal coolant loop is called the Experimental Lithium System (ELS) and has operated safely and reliably for over 6500 hours through September 1981. The loop is used for full-scale testing of components for the Fusion Materials Irradiation Test (FMIT) Facility. Main system parameters include coolant temperatures to 430 0 C and flow to 0.038 m 3 /s (600 gal/min). Performance of the main pump, vacuum system, and control system is discussed. Unique test capabilities of the ELS are also discussed

  15. Large coil test facility

    International Nuclear Information System (INIS)

    Nelms, L.W.; Thompson, P.B.

    1980-01-01

    Final design of the facility is nearing completion, and 20% of the construction has been accomplished. A large vacuum chamber, houses the test assembly which is coupled to appropriate cryogenic, electrical, instrumentation, diagnostc systems. Adequate assembly/disassembly areas, shop space, test control center, offices, and test support laboratories are located in the same building. Assembly and installation operations are accomplished with an overhead crane. The major subsystems are the vacuum system, the test stand assembly, the cryogenic system, the experimental electric power system, the instrumentation and control system, and the data aquisition system

  16. Large orbit neoclassical transport

    International Nuclear Information System (INIS)

    Lin, Z.; Tang, W.M.; Lee, W.W.

    1997-01-01

    Neoclassical transport in the presence of large ion orbits is investigated. The study is motivated by the recent experimental results that ion thermal transport levels in enhanced confinement tokamak plasmas fall below the open-quotes irreducible minimum levelclose quotes predicted by standard neoclassical theory. This apparent contradiction is resolved in the present analysis by relaxing the basic neoclassical assumption that the ions orbital excursions are much smaller than the local toroidal minor radius and the equilibrium scale lengths of the system. Analytical and simulation results are in agreement with trends from experiments. The development of a general formalism for neoclassical transport theory with finite orbit width is also discussed. copyright 1997 American Institute of Physics

  17. Large Superconducting Magnet Systems

    CERN Document Server

    Védrine, P.

    2014-07-17

    The increase of energy in accelerators over the past decades has led to the design of superconducting magnets for both accelerators and the associated detectors. The use of Nb−Ti superconducting materials allows an increase in the dipole field by up to 10 T compared with the maximum field of 2 T in a conventional magnet. The field bending of the particles in the detectors and generated by the magnets can also be increased. New materials, such as Nb$_{3}$Sn and high temperature superconductor (HTS) conductors, can open the way to higher fields, in the range 13–20 T. The latest generations of fusion machines producing hot plasma also use large superconducting magnet systems.

  18. Large Scale Solar Heating

    DEFF Research Database (Denmark)

    Heller, Alfred

    2001-01-01

    The main objective of the research was to evaluate large-scale solar heating connected to district heating (CSDHP), to build up a simulation tool and to demonstrate the application of the simulation tool for design studies and on a local energy planning case. The evaluation was mainly carried out...... model is designed and validated on the Marstal case. Applying the Danish Reference Year, a design tool is presented. The simulation tool is used for proposals for application of alternative designs, including high-performance solar collector types (trough solar collectors, vaccum pipe collectors......). Simulation programs are proposed as control supporting tool for daily operation and performance prediction of central solar heating plants. Finaly the CSHP technolgy is put into persepctive with respect to alternatives and a short discussion on the barries and breakthrough of the technology are given....

  19. Large Superconducting Magnet Systems

    Energy Technology Data Exchange (ETDEWEB)

    Védrine, P [Saclay (France)

    2014-07-01

    The increase of energy in accelerators over the past decades has led to the design of superconducting magnets for both accelerators and the associated detectors. The use of Nb−Ti superconducting materials allows an increase in the dipole field by up to 10 T compared with the maximum field of 2 T in a conventional magnet. The field bending of the particles in the detectors and generated by the magnets can also be increased. New materials, such as Nb3Sn and high temperature superconductor (HTS) conductors, can open the way to higher fields, in the range 13–20 T. The latest generations of fusion machines producing hot plasma also use large superconducting magnet systems.

  20. Large forging manufacturing process

    Science.gov (United States)

    Thamboo, Samuel V.; Yang, Ling

    2002-01-01

    A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750.degree. F. and 1800.degree. F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750.degree. F. and 1800.degree. F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725.degree. F. and 1750.degree. F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

  1. Large scale tracking algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ross L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Love, Joshua Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Melgaard, David Kennett [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Karelitz, David B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pitts, Todd Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zollweg, Joshua David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Anderson, Dylan Z. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nandy, Prabal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Whitlow, Gary L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bender, Daniel A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Byrne, Raymond Harry [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  2. The large binocular telescope.

    Science.gov (United States)

    Hill, John M

    2010-06-01

    The Large Binocular Telescope (LBT) Observatory is a collaboration among institutions in Arizona, Germany, Italy, Indiana, Minnesota, Ohio, and Virginia. The telescope on Mount Graham in Southeastern Arizona uses two 8.4 m diameter primary mirrors mounted side by side. A unique feature of the LBT is that the light from the two Gregorian telescope sides can be combined to produce phased-array imaging of an extended field. This cophased imaging along with adaptive optics gives the telescope the diffraction-limited resolution of a 22.65 m aperture and a collecting area equivalent to an 11.8 m circular aperture. This paper describes the design, construction, and commissioning of this unique telescope. We report some sample astronomical results with the prime focus cameras. We comment on some of the technical challenges and solutions. The telescope uses two F/15 adaptive secondaries to correct atmospheric turbulence. The first of these adaptive mirrors has completed final system testing in Firenze, Italy, and is planned to be at the telescope by Spring 2010.

  3. Large Format Radiographic Imaging

    International Nuclear Information System (INIS)

    Rohrer, J. S.; Stewart, Lacey; Wilke, M. D.; King, N. S.; Baker A, S.; Lewis, Wilfred

    1999-01-01

    Radiographic imaging continues to be a key diagnostic in many areas at Los Alamos National Laboratory (LANL). Radiographic recording systems have taken on many form, from high repetition-rate, gated systems to film recording and storage phosphors. Some systems are designed for synchronization to an accelerator while others may be single shot or may record a frame sequence in a dynamic radiography experiment. While film recording remains a reliable standby in the radiographic community, there is growing interest in investigating electronic recording for many applications. The advantages of real time access to remote data acquisition are highly attractive. Cooled CCD camera systems are capable of providing greater sensitivity with improved signal-to-noise ratio. This paper begins with a review of performance characteristics of the Bechtel Nevada large format imaging system, a gated system capable of viewing scintillators up to 300 mm in diameter. We then examine configuration alternatives in lens coupled and fiber optically coupled electro-optical recording systems. Areas of investigation include tradeoffs between fiber optic and lens coupling, methods of image magnification, and spectral matching from scintillator to CCD camera. Key performance features discussed include field of view, resolution, sensitivity, dynamic range, and system noise characteristics

  4. Large Ventral Hernia

    Directory of Open Access Journals (Sweden)

    Meryl Abrams, MD

    2018-04-01

    Full Text Available History of present illness: A 46-year-old female presented to the emergency department (ED with diffuse abdominal pain and three days of poor oral intake associated with non-bilious, non-bloody vomiting. Initial vital signs consisted of a mild resting tachycardia of 111 with a temperature of 38.0 degrees Celsius (°C. On examination, the patient had a large pannus extending to the knees, which contained a hernia. She was tender in this region on examination. Laboratory values included normal serum chemistries and mild leukocytosis of 12.2. The patient reports that her abdomen had been enlarging over the previous 8 years but had not been painful until 3 days prior to presentation. The patient had no associated fever, chills, diarrhea, constipation, chest pain or shortness of breath. Significant findings: Computed tomography (CT scan with intravenous (IV contrast of the abdomen and pelvis demonstrated a large pannus containing a ventral hernia with abdominal contents extending below the knees (white circle, elongation of mesenteric vessels to accommodate abdominal contents outside of the abdomen (white arrow and air fluid levels (white arrow indicating a small bowel obstruction. Discussion: Hernias are a common chief complaint seen in the emergency department. The estimated lifetime risk of a spontaneous abdominal hernia is 5%.1 The most common type of hernia is inguinal while the next most common type of hernia is femoral, which are more common in women.1 Ventral hernias can be epigastric, incisional, or primary abdominal. An asymptomatic, reducible hernia can be followed up as outpatient with a general surgeon for elective repair.2 Hernias become problematic when they are either incarcerated or strangulated. A hernia is incarcerated when the hernia is irreducible and strangulated when its blood supply is compromised. A complicated hernia, especially strangulated, can have a mortality of greater than 50%.1 It is key to perform a thorough history

  5. Tender in power-plants back to starting point

    International Nuclear Information System (INIS)

    TREND

    2003-01-01

    Even though there was no progress in privatisation of a 40-percent stake in Slovenske elektrarne (SE), a.s., Bratislava a government decree on re-opening of the tender issued in July will allow more prospects to participate. New prospects that are expected to submit their offers are Czech CEZ and American AES. At the same time the original eight prospects that submitted their offers earlier will have the opportunity to withdraw from the tender or review their offers. The new prospects can show their interest in requesting a information memorandum that will be published shortly and then PricewaterhouseCoopers (PwC) will state a date when the offers have to be submitted. After the original offers are updated and the new ones submitted, the offers will be evaluated. Representative of PwC, Peter Mitka refused to discuss the evaluation deadlines and the consecutive due diligence in SE to be conducted by selected investors. The company to have restarted the whole process was the Czech CEZ that had announces its intention to privatise not only the conventional part of SE but the nuclear part as well. The remaining prospects only show interest in hydraulic power plants or conventional power plants but none of them is interested in nuclear power plants. Even though the process is still open and theoretically other prospects could show their interest in the future, Minister of Economy, Robert Nemcsics does not expect that this step would be repeated. And so the number of prospects is ten. In the past the Minister expressed his view that the most suitable solution would be so sell the SE as a whole and during the first press conference given together with privatisation advisor the Minister explained that there was no time-pressure in regards to the privatisation process as an internal restructuring of the company had to be completed first

  6. Nuclear powerplant with closed gas-cooling circuit

    International Nuclear Information System (INIS)

    Haferkamp, D.; Hodzic, A.; Winter, U.

    1976-01-01

    Disclosed is a nuclear power plant comprising a pressure-tight safety vessel surrounding the entire plant, an inner vessel of reinforced concrete, a high-temperature reactor contained in the inner vessel, a gas turbine assembly having a turbine and a high- and low-pressure compressor located in a horizontally oriented chamber below the reactor, a plurality of heat exchange units positioned in a plurality of vertically oriented pods spaced radially symmetrically about the reactor and suitable conduits for carrying the reactive gas between the system components. The conduits are arranged in generally horizontally and vertically oriented straight lines, and the conduits for carrying low-pressure gas comprise a horizontal system positioned beneath the turbine assembly having a plurality of coaxial connecting tubes, collectors and distributors as well as normal conduits, so that high pressure gas flows in the internal passage and low-pressure gas flows in the outer passage. 22 claims, 7 figures

  7. Preparation of footing bottom of Temelin nuclear powerplant reactors

    International Nuclear Information System (INIS)

    Vyleta, M.

    1988-01-01

    The Temelin nuclear power site geologically belongs to the so-called monotonous moldanubium deposit. The site features a range of rocks, from easy to sort out rocks and rocks that can be mined using excavators, to difficult to sort out rocks that are necessary to be broken down, to rocks that are difficult to blast. The table in the main building site area was first lowered by 7 m to a ground elevation of 507.3 m, this in an area of 800x500 m. On the main four production unit sites, the working level of the reactor rooms and the engine rooms was lowered to a ground elevation of 502.3 m. The space of the first main production unit in an area of 70x70 m was excavated down to an elevation of 501.2 m, i.e. 1.1 m above the footing bottom of the first reactor. The technology is described in detail of building the footing bottom, based on the division of the whole area in 70 working fields (7x10 m) in which all working operations proceed in a closed cycle. It was thus guaranteed that the footing bottom would not disturbed with blasting operations or damaged as a result of the movement of building machines and vehicles on exposed rock. (Z.M.). 7 figs., 1 refs

  8. Study of fuel cell powerplant with heat recovery

    Science.gov (United States)

    King, J. M.; Grasso, A. P.; Clausi, J. V.

    1975-01-01

    It was shown that heat can be recovered from fuel cell power plants by replacing the air-cooled heat exchangers in present designs with units which transfer the heat to the integrated utility system. Energy availability for a 40-kW power plant was studied and showed that the total usable energy at rated power represents 84 percent of the fuel lower heating value. The effects of design variables on heat availability proved to be small. Design requirements were established for the heat recovery heat exchangers, including measurement of the characteristics of two candidate fuel cell coolants after exposure to fuel cell operating conditions. A heat exchanger test program was defined to assess fouling and other characteristics of fuel cell heat exchangers needed to confirm heat exchanger designs for heat recovery.

  9. LCA from Biomass Powerplants: from Soil to Electricity

    OpenAIRE

    François , Jessica; Fortin , Mathieu; Patisson , Fabrice; Mauviel , Guillain; Feidt , Michel; Rogaume , Caroline; Rogaume , Yann; Mirgaux , Olivier; Dufour , Anthony

    2013-01-01

    International audience; Biomass is one of the most promising renewable energy. The sustainability of biomass to energy chains needs to be assessed from the soil, including forest management, to the biomass valorization process. A strategy is presented to model the whole life cycle inventory of power production from biomass (beech). The forest growth, management and the wood valorization chain (including pulp, timber, etc., and energy) are modeled by a dedicated platform (called "CAPSIS"). It ...

  10. Biofouling of power-plant service systems by Corbicula

    International Nuclear Information System (INIS)

    Page, T.L.; Neitzel, D.A.; Simmons, M.A.; Hayes, P.F.

    1983-08-01

    Corbicula sp. foul the service water systems at nuclear power plants because the environment within these systems is compatible with the ecological requirements of the species. To reduce Corbicula fouling, components of service water systems and operating procedures that enhance the potential for fouling need to be identified. Factors important in mediating biofouling of service water systems appear to be screening potential, minimum and maximum velocities and the operational procedures employed during power plant biofoulant control and downtime. These conclusions are based on the results of a categorical model we used to correlate information from power plants with that on Corbicula life history. Power plant parameters in the model include temperature, dissolved oxygen concentration, screen and strainer size, maximum and minimum velocities, and elements of the biofouling control procedures. Parameters for Corbicula include tolerances to temperature, dissolved oxygen, biofouling control chemicals, velocity preferences, and optimal temperatures for each life stage and behavior. 13 references, 5 figures

  11. Experience with managing, operating and maintaining gas turbine powerplants

    International Nuclear Information System (INIS)

    Wadman, B.

    1994-01-01

    Stewart ampersand Stevenson, a major supplier of gas turbine powered cogeneration systems to worldwide markets, established plant management, operations and maintenance capabilities in 1985 in order to provide complete service capability to the customer. As of the fall of 1993, twenty-two individual cogeneration facilities are now being operated and maintained by this company with a total capacity of 1100+ MW. More than 300 plant management and operating personnel are employed in this operation. To date, activities have been concentrated in North and South America. Negotiations are in process in a number of other areas including the Pacific Rim, China, and several Middle East countries. 7 figs

  12. Computing and cognition in future power-plant operations

    International Nuclear Information System (INIS)

    Kisner, R.A.; Sheridan, T.B.

    1983-01-01

    The intent of this paper is to speculate on the nature of future interactions between people and computers in the operation of power plants. In particular, the authors offer a taxonomy for examining the differing functions of operators in interacting with the plant and its computers, and the differing functions of the computers in interacting with the plant and its operators

  13. 10 CFR 504.9 - Environmental requirements for certifying powerplants.

    Science.gov (United States)

    2010-01-01

    ... information. In addition, OFP will have the authority to approve and modify any statement, analysis, and... the costs of preparing any necessary Environmental Assessment (EA) or Environmental Impact Statement... review and prepare an EA or EIS, as appropriate, and who does not have a financial or other interest in...

  14. A chicken in every pot, a new boiler in every powerplant, a new powerplant at every industrial site

    Energy Technology Data Exchange (ETDEWEB)

    Bessette, R.D. [Council of Industrial Boiler Owners, Burke, VA (United States)

    1997-12-31

    The paper discusses the pressures on the industrial boiler owner today which affect how he meets his energy needs. As a result of these pressures, especially the environmental regulations, the author sees some major trends which may be indicative of what the future will hold and he discusses these. The author finally describes what the industrial power plant will be in the next 10--20 years.

  15. Unification, small and large

    Energy Technology Data Exchange (ETDEWEB)

    Fritzsch, Harald

    1993-04-15

    Full text: Fruitful exchanges between particle physics, astrophysics and cosmology have become a common feature in the last decade. In January, Coral Gables near Miami was the stage for a 'Unified Symmetry in the Small and the Large' meeting. Coral Gables is a famous physics venue. In January 1964, the year that the quark model of hadrons emerged, Behram Kursunoglu initiated a series of particle physics meetings that continued for 20 years and formed a regular focus for this development. The final such meeting was in 1983, coinciding with both the 80th birthday of field theory pioneer Paul Dirac, who worked in Florida towards the end of his career, and the discovery of the W bosons at CERN. The resurrected Coral Gables meeting began with historical accounts of the emergence of Big Bang cosmology, by Robert Ralph and Herman Alpher, while Andrei Linde proposed our expanding universe as a small part of a stationary system, infinite both in space and in time. The observational status of Big Bang cosmology was reviewed by Bruce Partridge, John Mather and Martin Harwit, emphasizing the cosmic background radiation, where temperature is now measured by the COBE satellite detectors to 2.726 ± 0.01 OK. The tiny fluctuations observed by COBE pose problems for standard cold dark matter models. Edward ('Rocky') Kolb reported on new studies on the electroweak phase transition, based on an analogy with the physics of liquid crystals. Richard Holman discussed the fate of global symmetries at energies near the Planck (grand unification) energy, and Paul Steinhardt talked about tensorial and scalar metric fluctuations in the light of the COBE results. Anthony Tyson gave an impressive description of dark matter studies using gravitational lensing, now emerging as a unique tool for indirectly observing intervening dark matter. A neutrino mass of 10 electronvolts could account for observed dark matter distributions, but fails to provide the necessary seeds for galaxy formation. A

  16. Unification, small and large

    International Nuclear Information System (INIS)

    Fritzsch, Harald

    1993-01-01

    Full text: Fruitful exchanges between particle physics, astrophysics and cosmology have become a common feature in the last decade. In January, Coral Gables near Miami was the stage for a 'Unified Symmetry in the Small and the Large' meeting. Coral Gables is a famous physics venue. In January 1964, the year that the quark model of hadrons emerged, Behram Kursunoglu initiated a series of particle physics meetings that continued for 20 years and formed a regular focus for this development. The final such meeting was in 1983, coinciding with both the 80th birthday of field theory pioneer Paul Dirac, who worked in Florida towards the end of his career, and the discovery of the W bosons at CERN. The resurrected Coral Gables meeting began with historical accounts of the emergence of Big Bang cosmology, by Robert Ralph and Herman Alpher, while Andrei Linde proposed our expanding universe as a small part of a stationary system, infinite both in space and in time. The observational status of Big Bang cosmology was reviewed by Bruce Partridge, John Mather and Martin Harwit, emphasizing the cosmic background radiation, where temperature is now measured by the COBE satellite detectors to 2.726 ± 0.01 OK. The tiny fluctuations observed by COBE pose problems for standard cold dark matter models. Edward ('Rocky') Kolb reported on new studies on the electroweak phase transition, based on an analogy with the physics of liquid crystals. Richard Holman discussed the fate of global symmetries at energies near the Planck (grand unification) energy, and Paul Steinhardt talked about tensorial and scalar metric fluctuations in the light of the COBE results. Anthony Tyson gave an impressive description of dark matter studies using gravitational lensing, now emerging as a unique tool for indirectly observing intervening dark matter. A neutrino mass of 10 electronvolts could account for observed dark matter distributions, but fails to provide the necessary seeds for

  17. Laboratory for Large Data Research

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The Laboratory for Large Data Research (LDR) addresses a critical need to rapidly prototype shared, unified access to large amounts of data across both the...

  18. Large-D gravity and low-D strings.

    Science.gov (United States)

    Emparan, Roberto; Grumiller, Daniel; Tanabe, Kentaro

    2013-06-21

    We show that in the limit of a large number of dimensions a wide class of nonextremal neutral black holes has a universal near-horizon limit. The limiting geometry is the two-dimensional black hole of string theory with a two-dimensional target space. Its conformal symmetry explains the properties of massless scalars found recently in the large-D limit. For black branes with string charges, the near-horizon geometry is that of the three-dimensional black strings of Horne and Horowitz. The analogies between the α' expansion in string theory and the large-D expansion in gravity suggest a possible effective string description of the large-D limit of black holes. We comment on applications to several subjects, in particular to the problem of critical collapse.

  19. Quenches in large superconducting magnets

    International Nuclear Information System (INIS)

    Eberhard, P.H.; Alston-Garnjost, M.; Green, M.A.; Lecomte, P.; Smits, R.G.; Taylor, J.D.; Vuillemin, V.

    1977-08-01

    The development of large high current density superconducting magnets requires an understanding of the quench process by which the magnet goes normal. A theory which describes the quench process in large superconducting magnets is presented and compared with experimental measurements. The use of a quench theory to improve the design of large high current density superconducting magnets is discussed

  20. Health impacts of large dams

    International Nuclear Information System (INIS)

    Lerer, L.B.

    1999-01-01

    Large dams have been criticized because of their negative environmental and social impacts. Public health interest largely has focused on vector-borne diseases, such as schistosomiasis, associated with reservoirs and irrigation projects. Large dams also influence health through changes in water and food security, increases in communicable diseases, and the social disruption caused by construction and involuntary resettlement. Communities living in close proximity to large dams often do not benefit from water transfer and electricity generation revenues. A comprehensive health component is required in environmental and social impact assessments for large dam projects

  1. Large deviations and idempotent probability

    CERN Document Server

    Puhalskii, Anatolii

    2001-01-01

    In the view of many probabilists, author Anatolii Puhalskii''s research results stand among the most significant achievements in the modern theory of large deviations. In fact, his work marked a turning point in the depth of our understanding of the connections between the large deviation principle (LDP) and well-known methods for establishing weak convergence results.Large Deviations and Idempotent Probability expounds upon the recent methodology of building large deviation theory along the lines of weak convergence theory. The author develops an idempotent (or maxitive) probability theory, introduces idempotent analogues of martingales (maxingales), Wiener and Poisson processes, and Ito differential equations, and studies their properties. The large deviation principle for stochastic processes is formulated as a certain type of convergence of stochastic processes to idempotent processes. The author calls this large deviation convergence.The approach to establishing large deviation convergence uses novel com...

  2. Large-scale grid management

    International Nuclear Information System (INIS)

    Langdal, Bjoern Inge; Eggen, Arnt Ove

    2003-01-01

    The network companies in the Norwegian electricity industry now have to establish a large-scale network management, a concept essentially characterized by (1) broader focus (Broad Band, Multi Utility,...) and (2) bigger units with large networks and more customers. Research done by SINTEF Energy Research shows so far that the approaches within large-scale network management may be structured according to three main challenges: centralization, decentralization and out sourcing. The article is part of a planned series

  3. Large-scale solar purchasing

    International Nuclear Information System (INIS)

    1999-01-01

    The principal objective of the project was to participate in the definition of a new IEA task concerning solar procurement (''the Task'') and to assess whether involvement in the task would be in the interest of the UK active solar heating industry. The project also aimed to assess the importance of large scale solar purchasing to UK active solar heating market development and to evaluate the level of interest in large scale solar purchasing amongst potential large scale purchasers (in particular housing associations and housing developers). A further aim of the project was to consider means of stimulating large scale active solar heating purchasing activity within the UK. (author)

  4. Physics with large extra dimensions

    Indian Academy of Sciences (India)

    can then be accounted by the existence of large internal dimensions, in the sub- ... strongly coupled heterotic theory with one large dimension is described by a weakly ..... one additional U(1) factor corresponding to an extra 'U(1)' D-brane is ...

  5. MPQS with three large primes

    NARCIS (Netherlands)

    Leyland, P.; Lenstra, A.K.; Dodson, B.; Muffett, A.; Wagstaff, S.; Fieker, C.; Kohel, D.R.

    2002-01-01

    We report the factorization of a 135-digit integer by the triple-large-prime variation of the multiple polynomial quadratic sieve. Previous workers [6][10] had suggested that using more than two large primes would be counterproductive, because of the greatly increased number of false reports from

  6. Querying Large Biological Network Datasets

    Science.gov (United States)

    Gulsoy, Gunhan

    2013-01-01

    New experimental methods has resulted in increasing amount of genetic interaction data to be generated every day. Biological networks are used to store genetic interaction data gathered. Increasing amount of data available requires fast large scale analysis methods. Therefore, we address the problem of querying large biological network datasets.…

  7. Large-scale data analytics

    CERN Document Server

    Gkoulalas-Divanis, Aris

    2014-01-01

    Provides cutting-edge research in large-scale data analytics from diverse scientific areas Surveys varied subject areas and reports on individual results of research in the field Shares many tips and insights into large-scale data analytics from authors and editors with long-term experience and specialization in the field

  8. Mobility and powering of large detectors. Moving large detectors

    International Nuclear Information System (INIS)

    Thompson, J.

    1977-01-01

    The possibility is considered of moving large lepton detectors at ISABELLE for readying new experiments, detector modifications, and detector repair. A large annex (approximately 25 m x 25 m) would be built adjacent to the Lepton Hall separated from the Lepton Hall by a wall of concrete 11 m high x 12 m wide (for clearance of the detector) and approximately 3 m thick (for radiation shielding). A large pad would support the detector, the door, the cryogenic support system and the counting house. In removing the detector from the beam hall, one would push the pad into the annex, add a dummy beam pipe, bake out the beam pipe, and restack and position the wall on a small pad at the door. The beam could then operate again while experimenters could work on the large detector in the annex. A consideration and rough price estimate of various questions and proposed solutions are given

  9. Measuring happiness in large population

    Science.gov (United States)

    Wenas, Annabelle; Sjahputri, Smita; Takwin, Bagus; Primaldhi, Alfindra; Muhamad, Roby

    2016-01-01

    The ability to know emotional states for large number of people is important, for example, to ensure the effectiveness of public policies. In this study, we propose a measure of happiness that can be used in large scale population that is based on the analysis of Indonesian language lexicons. Here, we incorporate human assessment of Indonesian words, then quantify happiness on large-scale of texts gathered from twitter conversations. We used two psychological constructs to measure happiness: valence and arousal. We found that Indonesian words have tendency towards positive emotions. We also identified several happiness patterns during days of the week, hours of the day, and selected conversation topics.

  10. Large Hadron Collider nears completion

    CERN Multimedia

    2008-01-01

    Installation of the final component of the Large Hadron Collider particle accelerator is under way along the Franco-Swiss border near Geneva, Switzerland. When completed this summer, the LHC will be the world's largest and most complex scientific instrument.

  11. Phenomenology of large Nc QCD

    International Nuclear Information System (INIS)

    Lebed, R.F.

    1999-01-01

    These lectures are designed to introduce the methods and results of large N c QCD in a presentation intended for nuclear and particle physicists alike. Beginning with definitions and motivations of the approach, we demonstrate that all quark and gluon Feynman diagrams are organized into classes based on powers of 1/N c . We then show that this result can be translated into definite statements about mesons and baryons containing arbitrary numbers of constituents. In the mesons, numerous well-known phenomenological properties follow as immediate consequences of simply counting powers of N c , while for the baryons, quantitative large N c analyses of masses and other properties are seen to agree with experiment, even when 'large' N c is set equal to its observed value of 3. Large N c reasoning is also used to explain some simple features of nuclear interactions. (author)

  12. Phenomenology of large Nc QCD

    International Nuclear Information System (INIS)

    Richard Lebed

    1998-01-01

    These lectures are designed to introduce the methods and results of large N c QCD in a presentation intended for nuclear and particle physicists alike. Beginning with definitions and motivations of the approach, they demonstrate that all quark and gluon Feynman diagrams are organized into classes based on powers of 1/N c . They then show that this result can be translated into definite statements about mesons and baryons containing arbitrary numbers of constituents. In the mesons, numerous well-known phenomenological properties follow as immediate consequences of simply counting powers of N c , while for the baryons, quantitative large N c analyses of masses and other properties are seen to agree with experiment, even when ''large'' N c is set equal to its observed value of 3. Large N c reasoning is also used to explain some simple features of nuclear interactions

  13. Community Detection for Large Graphs

    KAUST Repository

    Peng, Chengbin; Kolda, Tamara G.; Pinar, Ali; Zhang, Zhihua; Keyes, David E.

    2014-01-01

    Many real world networks have inherent community structures, including social networks, transportation networks, biological networks, etc. For large scale networks with millions or billions of nodes in real-world applications, accelerating current

  14. Physics with large extra dimensions

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 62; Issue 2 ... The recent understanding of string theory opens the possibility that the string scale can be as ... by the existence of large internal dimensions, in the sub-millimeter region.

  15. Utility unbundling : large consumer's perspective

    International Nuclear Information System (INIS)

    Block, C.

    1997-01-01

    The perspectives of Sunoco as a large user of electric power on utility unbundling were presented. Sunoco's Sarnia refinery runs up an energy bill of over $60 million per year for electricity, natural gas (used both as a feedstock as well as a fuel), natural gas liquids and steam. As a large customer Sunoco advocates unbundling of all services, leaving only the 'pipes and wires' as true monopolies. In their view, regulation distorts the market place and prevents the lower prices that would result from competition as has been seen in the airline and telephone industries. Sunoco's expectation is that in the post-deregulated environment large and small consumers will have a choice of energy supplier, and large consumers will increasingly turn to co-generation as the most desirable way of meeting their power needs

  16. LSD: Large Survey Database framework

    Science.gov (United States)

    Juric, Mario

    2012-09-01

    The Large Survey Database (LSD) is a Python framework and DBMS for distributed storage, cross-matching and querying of large survey catalogs (>10^9 rows, >1 TB). The primary driver behind its development is the analysis of Pan-STARRS PS1 data. It is specifically optimized for fast queries and parallel sweeps of positionally and temporally indexed datasets. It transparently scales to more than >10^2 nodes, and can be made to function in "shared nothing" architectures.

  17. Large-scale solar heat

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics

    1998-12-31

    In this project a large domestic solar heating system was built and a solar district heating system was modelled and simulated. Objectives were to improve the performance and reduce costs of a large-scale solar heating system. As a result of the project the benefit/cost ratio can be increased by 40 % through dimensioning and optimising the system at the designing stage. (orig.)

  18. Optimization theory for large systems

    CERN Document Server

    Lasdon, Leon S

    2002-01-01

    Important text examines most significant algorithms for optimizing large systems and clarifying relations between optimization procedures. Much data appear as charts and graphs and will be highly valuable to readers in selecting a method and estimating computer time and cost in problem-solving. Initial chapter on linear and nonlinear programming presents all necessary background for subjects covered in rest of book. Second chapter illustrates how large-scale mathematical programs arise from real-world problems. Appendixes. List of Symbols.

  19. Hidden supersymmetry and large N

    International Nuclear Information System (INIS)

    Alfaro, J.

    1988-01-01

    In this paper we present a new method to deal with the leading order in the large-N expansion of a quantum field theory. The method uses explicitly the hidden supersymmetry that is present in the path-integral formulation of a stochastic process. In addition to this we derive a new relation that is valid in the leading order of the large-N expansion of the hermitian-matrix model for any spacetime dimension. (orig.)

  20. Large transverse momentum hadronic processes

    International Nuclear Information System (INIS)

    Darriulat, P.

    1977-01-01

    The possible relations between deep inelastic leptoproduction and large transverse momentum (psub(t)) processes in hadronic collisions are usually considered in the framework of the quark-parton picture. Experiments observing the structure of the final state in proton-proton collisions producing at least one large transverse momentum particle have led to the following conclusions: a large fraction of produced particles are uneffected by the large psub(t) process. The other products are correlated to the large psub(t) particle. Depending upon the sign of scalar product they can be separated into two groups of ''towards-movers'' and ''away-movers''. The experimental evidence are reviewed favouring such a picture and the properties are discussed of each of three groups (underlying normal event, towards-movers and away-movers). Some phenomenological interpretations are presented. The exact nature of away- and towards-movers must be further investigated. Their apparent jet structure has to be confirmed. Angular correlations between leading away and towards movers are very informative. Quantum number flow, both within the set of away and towards-movers, and between it and the underlying normal event, are predicted to behave very differently in different models

  1. The large-s field-reversed configuration experiment

    International Nuclear Information System (INIS)

    Hoffman, A.L.; Carey, L.N.; Crawford, E.A.; Harding, D.G.; DeHart, T.E.; McDonald, K.F.; McNeil, J.L.; Milroy, R.D.; Slough, J.T.; Maqueda, R.; Wurden, G.A.

    1993-01-01

    The Large-s Experiment (LSX) was built to study the formation and equilibrium properties of field-reversed configurations (FRCs) as the scale size increases. The dynamic, field-reversed theta-pinch method of FRC creation produces axial and azimuthal deformations and makes formation difficult, especially in large devices with large s (number of internal gyroradii) where it is difficult to achieve initial plasma uniformity. However, with the proper technique, these formation distortions can be minimized and are then observed to decay with time. This suggests that the basic stability and robustness of FRCs formed, and in some cases translated, in smaller devices may also characterize larger FRCs. Elaborate formation controls were included on LSX to provide the initial uniformity and symmetry necessary to minimize formation disturbances, and stable FRCs could be formed up to the design goal of s = 8. For x ≤ 4, the formation distortions decayed away completely, resulting in symmetric equilibrium FRCs with record confinement times up to 0.5 ms, agreeing with previous empirical scaling laws (τ∝sR). Above s = 4, reasonably long-lived (up to 0.3 ms) configurations could still be formed, but the initial formation distortions were so large that they never completely decayed away, and the equilibrium confinement was degraded from the empirical expectations. The LSX was only operational for 1 yr, and it is not known whether s = 4 represents a fundamental limit for good confinement in simple (no ion beam stabilization) FRCs or whether it simply reflects a limit of present formation technology. Ideally, s could be increased through flux buildup from neutral beams. Since the addition of kinetic or beam ions will probably be desirable for heating, sustainment, and further stabilization of magnetohydrodynamic modes at reactor-level s values, neutral beam injection is the next logical step in FRC development. 24 refs., 21 figs., 2 tabs

  2. Large aperture optical switching devices

    International Nuclear Information System (INIS)

    Goldhar, J.; Henesian, M.A.

    1983-01-01

    We have developed a new approach to constructing large aperture optical switches for next generation inertial confinement fusion lasers. A transparent plasma electrode formed in low pressure ionized gas acts as a conductive coating to allow the uniform charging of the optical faces of an electro-optic material. In this manner large electric fields can be applied longitudinally to large aperture, high aspect ratio Pockels cells. We propose a four-electrode geometry to create the necessary high conductivity plasma sheets, and have demonstrated fast (less than 10 nsec) switching in a 5x5 cm aperture KD*P Pockels cell with such a design. Detaid modelling of Pockels cell performance with plasma electrodes has been carried out for 15 and 30 cm aperture designs

  3. Assembling large, complex environmental metagenomes

    Energy Technology Data Exchange (ETDEWEB)

    Howe, A. C. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Plant Soil and Microbial Sciences; Jansson, J. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Earth Sciences Division; Malfatti, S. A. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Tringe, S. G. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States); Tiedje, J. M. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Plant Soil and Microbial Sciences; Brown, C. T. [Michigan State Univ., East Lansing, MI (United States). Microbiology and Molecular Genetics, Computer Science and Engineering

    2012-12-28

    The large volumes of sequencing data required to sample complex environments deeply pose new challenges to sequence analysis approaches. De novo metagenomic assembly effectively reduces the total amount of data to be analyzed but requires significant computational resources. We apply two pre-assembly filtering approaches, digital normalization and partitioning, to make large metagenome assemblies more computationaly tractable. Using a human gut mock community dataset, we demonstrate that these methods result in assemblies nearly identical to assemblies from unprocessed data. We then assemble two large soil metagenomes from matched Iowa corn and native prairie soils. The predicted functional content and phylogenetic origin of the assembled contigs indicate significant taxonomic differences despite similar function. The assembly strategies presented are generic and can be extended to any metagenome; full source code is freely available under a BSD license.

  4. Large scale structure and baryogenesis

    International Nuclear Information System (INIS)

    Kirilova, D.P.; Chizhov, M.V.

    2001-08-01

    We discuss a possible connection between the large scale structure formation and the baryogenesis in the universe. An update review of the observational indications for the presence of a very large scale 120h -1 Mpc in the distribution of the visible matter of the universe is provided. The possibility to generate a periodic distribution with the characteristic scale 120h -1 Mpc through a mechanism producing quasi-periodic baryon density perturbations during inflationary stage, is discussed. The evolution of the baryon charge density distribution is explored in the framework of a low temperature boson condensate baryogenesis scenario. Both the observed very large scale of a the visible matter distribution in the universe and the observed baryon asymmetry value could naturally appear as a result of the evolution of a complex scalar field condensate, formed at the inflationary stage. Moreover, for some model's parameters a natural separation of matter superclusters from antimatter ones can be achieved. (author)

  5. Large ceramics for fusion applications

    International Nuclear Information System (INIS)

    Hauth, W.E.; Stoddard, S.D.

    1979-01-01

    Prominent ceramic raw materials and products manufacturers were surveyed to determine the state of the art for alumina ceramic fabrication. This survey emphasized current capabilities and limitations for fabrication of large, high-density, high-purity, complex shapes. Some directions are suggested for future needs and development. Ceramic-to-ceramic sealing has applications for several technologies that require large and/or complex vacuum-tight ceramic shapes. Information is provided concerning the assembly of complex monolithic ceramic shapes by bonding of subassemblies at temperatures ranging from 450 to 1500 0 C. Future applications and fabrication techniques for various materials are presented

  6. Dijets at large rapidity intervals

    CERN Document Server

    Pope, B G

    2001-01-01

    Inclusive diet production at large pseudorapidity intervals ( Delta eta ) between the two jets has been suggested as a regime for observing BFKL dynamics. We have measured the dijet cross section for large Delta eta in pp collisions at square root s = 1800 and 630 GeV using the DOE detector. The partonic cross section increases strongly with the size of Delta eta . The observed growth is even stronger than expected on the basis of BFKL resummation in the leading logarithmic approximation. The growth of the partonic cross section can be accommodated with an effective BFKL intercept of alpha /sub BFKL/(20 GeV) = 1.65 +or- 0.07.

  7. Large Eddy Simulation of turbulence

    International Nuclear Information System (INIS)

    Poullet, P.; Sancandi, M.

    1994-12-01

    Results of Large Eddy Simulation of 3D isotropic homogeneous turbulent flows are presented. A computer code developed on Connexion Machine (CM5) has allowed to compare two turbulent viscosity models (Smagorinsky and structure function). The numerical scheme influence on the energy density spectrum is also studied [fr

  8. The Large Vector Multiplet Action

    OpenAIRE

    Ryb, Itai

    2007-01-01

    We discuss possible actions for the d=2, N=(2,2) large vector multiplet that gauges isometries of generalized Kahler geometries. We explore two scenarios that allow us to write kinetic and superpotential terms for the scalar field-strengths, and write kinetic terms for the spinor invariants that can introduce topological terms for the connections.

  9. Qatar - large capital investment planned

    International Nuclear Information System (INIS)

    Roberts, J.

    1996-01-01

    Large capital investments are planned throughout Qatar's energy industry over the next five years totalling $25 billion. This article describes the successful commissioning of Qatar's first liquefied natural gas (LNG) project on time and within budget. The second LNG plant is well underway and plans for a third are under negotiation. (UK)

  10. Large deviations and portfolio optimization

    Science.gov (United States)

    Sornette, Didier

    Risk control and optimal diversification constitute a major focus in the finance and insurance industries as well as, more or less consciously, in our everyday life. We present a discussion of the characterization of risks and of the optimization of portfolios that starts from a simple illustrative model and ends by a general functional integral formulation. A major item is that risk, usually thought of as one-dimensional in the conventional mean-variance approach, has to be addressed by the full distribution of losses. Furthermore, the time-horizon of the investment is shown to play a major role. We show the importance of accounting for large fluctuations and use the theory of Cramér for large deviations in this context. We first treat a simple model with a single risky asset that exemplifies the distinction between the average return and the typical return and the role of large deviations in multiplicative processes, and the different optimal strategies for the investors depending on their size. We then analyze the case of assets whose price variations are distributed according to exponential laws, a situation that is found to describe daily price variations reasonably well. Several portfolio optimization strategies are presented that aim at controlling large risks. We end by extending the standard mean-variance portfolio optimization theory, first within the quasi-Gaussian approximation and then using a general formulation for non-Gaussian correlated assets in terms of the formalism of functional integrals developed in the field theory of critical phenomena.

  11. Inconsistency in large pharmacogenomic studies

    DEFF Research Database (Denmark)

    Haibe-Kains, Benjamin; El-Hachem, Nehme; Birkbak, Nicolai Juul

    2013-01-01

    Two large-scale pharmacogenomic studies were published recently in this journal. Genomic data are well correlated between studies; however, the measured drug response data are highly discordant. Although the source of inconsistencies remains uncertain, it has potential implications for using...

  12. Strategic Management of Large Projects

    Institute of Scientific and Technical Information of China (English)

    WangYingluo; LiuYi; LiYuan

    2004-01-01

    The strategic management of large projects is both theoretically and practically important. Some scholars have advanced flexible strategy theory in China. The difference of strategic flexibility and flexible strategy is pointed out. The supporting system and characteristics of flexible strategy are analyzed. The changes of flexible strategy and integration of strategic management are discussed.

  13. Mass spectrometry of large molecules

    International Nuclear Information System (INIS)

    Facchetti, S.

    1985-01-01

    The lectures in this volume were given at a course on mass spectrometry of large molecules, organized within the framework of the Training and Education programme of the Joint Research Centre of the European Communities. Although first presented in 1983, most of the lectures have since been updated by their authors. (orig.)

  14. Large for Gestational Age (LGA)

    Science.gov (United States)

    ... mother Other risk factors for having large-for-gestational-age newborns include Maternal obesity Having had previous LGA babies Genetic abnormalities or syndromes (for example, Beckwith-Wiedemann syndrome or Sotos syndrome) Excessive weight gain during pregnancy (the fetus gets more calories as ...

  15. Large-scale pool fires

    Directory of Open Access Journals (Sweden)

    Steinhaus Thomas

    2007-01-01

    Full Text Available A review of research into the burning behavior of large pool fires and fuel spill fires is presented. The features which distinguish such fires from smaller pool fires are mainly associated with the fire dynamics at low source Froude numbers and the radiative interaction with the fire source. In hydrocarbon fires, higher soot levels at increased diameters result in radiation blockage effects around the perimeter of large fire plumes; this yields lower emissive powers and a drastic reduction in the radiative loss fraction; whilst there are simplifying factors with these phenomena, arising from the fact that soot yield can saturate, there are other complications deriving from the intermittency of the behavior, with luminous regions of efficient combustion appearing randomly in the outer surface of the fire according the turbulent fluctuations in the fire plume. Knowledge of the fluid flow instabilities, which lead to the formation of large eddies, is also key to understanding the behavior of large-scale fires. Here modeling tools can be effectively exploited in order to investigate the fluid flow phenomena, including RANS- and LES-based computational fluid dynamics codes. The latter are well-suited to representation of the turbulent motions, but a number of challenges remain with their practical application. Massively-parallel computational resources are likely to be necessary in order to be able to adequately address the complex coupled phenomena to the level of detail that is necessary.

  16. Active Learning in Large Classes

    DEFF Research Database (Denmark)

    Gørtz, Inge Li

    2011-01-01

    teaching large classes (more than 50 students), and describe how we successfully have in a second semester course in the Bachelor of Engineering (BEng) and Bachelor of Science Engineering (BSc Eng) program at the Technical University of Denmark (DTU). Approximately 200 students is attending...

  17. Adding large EM stack support

    KAUST Repository

    Holst, Glendon

    2016-12-01

    Serial section electron microscopy (SSEM) image stacks generated using high throughput microscopy techniques are an integral tool for investigating brain connectivity and cell morphology. FIB or 3View scanning electron microscopes easily generate gigabytes of data. In order to produce analyzable 3D dataset from the imaged volumes, efficient and reliable image segmentation is crucial. Classical manual approaches to segmentation are time consuming and labour intensive. Semiautomatic seeded watershed segmentation algorithms, such as those implemented by ilastik image processing software, are a very powerful alternative, substantially speeding up segmentation times. We have used ilastik effectively for small EM stacks – on a laptop, no less; however, ilastik was unable to carve the large EM stacks we needed to segment because its memory requirements grew too large – even for the biggest workstations we had available. For this reason, we refactored the carving module of ilastik to scale it up to large EM stacks on large workstations, and tested its efficiency. We modified the carving module, building on existing blockwise processing functionality to process data in manageable chunks that can fit within RAM (main memory). We review this refactoring work, highlighting the software architecture, design choices, modifications, and issues encountered.

  18. Protection of large capacitor banks

    International Nuclear Information System (INIS)

    Sprott, J.C.; Lovell, T.W.

    1982-06-01

    Large capacitor banks, as used in many pulsed plasma experiments, are subject to catastrophic failure in the event of a short in the output or in an individual capacitor. Methods are described for protecting such banks to minimize the damage and down-time caused by such a failure

  19. CERN's Large Hadron Collider project

    Science.gov (United States)

    Fearnley, Tom A.

    1997-03-01

    The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B.

  20. CERN's Large Hadron Collider project

    International Nuclear Information System (INIS)

    Fearnley, Tom A.

    1997-01-01

    The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B

  1. Large area CMOS image sensors

    International Nuclear Information System (INIS)

    Turchetta, R; Guerrini, N; Sedgwick, I

    2011-01-01

    CMOS image sensors, also known as CMOS Active Pixel Sensors (APS) or Monolithic Active Pixel Sensors (MAPS), are today the dominant imaging devices. They are omnipresent in our daily life, as image sensors in cellular phones, web cams, digital cameras, ... In these applications, the pixels can be very small, in the micron range, and the sensors themselves tend to be limited in size. However, many scientific applications, like particle or X-ray detection, require large format, often with large pixels, as well as other specific performance, like low noise, radiation hardness or very fast readout. The sensors are also required to be sensitive to a broad spectrum of radiation: photons from the silicon cut-off in the IR down to UV and X- and gamma-rays through the visible spectrum as well as charged particles. This requirement calls for modifications to the substrate to be introduced to provide optimized sensitivity. This paper will review existing CMOS image sensors, whose size can be as large as a single CMOS wafer, and analyse the technical requirements and specific challenges of large format CMOS image sensors.

  2. The large hadron collider project

    International Nuclear Information System (INIS)

    Maiani, L.

    1999-01-01

    Knowledge of the fundamental constituents of matter has greatly advanced, over the last decades. The standard theory of fundamental interactions presents us with a theoretically sound picture, which describes with great accuracy known physical phenomena on most diverse energy and distance scales. These range from 10 -16 cm, inside the nucleons, up to large-scale astrophysical bodies, including the early Universe at some nanosecond after the Big-Bang and temperatures of the order of 10 2 GeV. The picture is not yet completed, however, as we lack the observation of the Higgs boson, predicted in the 100-500 GeV range - a particle associated with the generation of particle masses and with the quantum fluctuations in the primordial Universe. In addition, the standard theory is expected to undergo a change of regime in the 10 3 GeV region, with the appearance of new families of particles, most likely associated with the onset of a new symmetry (supersymmetry). In 1994, the CERN Council approved the construction of the large hadron collider (LHC), a proton-proton collider of a new design to be installed in the existing LEP tunnel, with an energy of 7 TeV per beam and extremely large luminosity, of ∝10 34 cm -2 s -1 . Construction was started in 1996, with the additional support of the US, Japan, Russia, Canada and other European countries, making the LHC a really global project, the first one in particle physics. After a short review of the physics scenario, I report on the present status of the LHC construction. Special attention is given to technological problems such as the realization of the super-conducting dipoles, following an extensive R and D program with European industries. The construction of the large LHC detectors has required a vast R and D program by a large international community, to overcome the problems posed by the complexity of the collisions and by the large luminosity of the machine. (orig.)

  3. Degassing a large LHe cryopump

    International Nuclear Information System (INIS)

    Denhoy, B.S.; Batzer, T.H.; Call, W.R.

    1977-01-01

    A method has been developed and successfully tested to degas a large LHe cryopump. Use of this method inhibits the normally excessive pressure rise during the degassing cycle when the degassing rate exceeds the external pumping capabilities of the system. A small appendage pump, installed close to the main cryopump, absorbs all the gas, as it is desorbed from the main cryopump, with no rise in the system pressure. The appendage pump can then be isolated from the main vacuum system and degassed at high pressure. We pumped 15 to 20 x 10 3 Torr . 1 of H 2 on a 1.25 m 2 panel. During the degassing cycle the system pressure never rose above 1 x 10 -4 Torr. In large vacuum systems for future fusion machines that contain cryopump panels as well as cryogenic magnets, this method is a unique and very useful tool. It will allow the degassing of cryopumps without affecting the temperature equilibrium of cryogenic magnets

  4. Large-capacity current leads

    International Nuclear Information System (INIS)

    Ballarino, A.

    2008-01-01

    Feeding superconducting magnets with reliable low-loss devices is a key issue for any cryo-electrical system. Conventional or HTS current leads can be used, and cooling methods, materials, and geometries can be chosen to optimize the thermo-electrical performance of the system. The LHC magnets are powered via more than 3000 current leads transporting altogether about 3 MA of current. With thousands of leads, the LHC lead project represents today the largest project of its kind ever undertaken. Following a review of the LHC lead project, an overview of the choices that can be made for the optimization of large capacity current leads is presented. Examples are given of other leads for large scale magnet systems for which the use of HTS is being envisaged

  5. Large Aspect Ratio Tokamak Study

    International Nuclear Information System (INIS)

    Reid, R.L.; Holmes, J.A.; Houlberg, W.A.; Peng, Y.K.M.; Strickler, D.J.; Brown, T.G.; Wiseman, G.W.

    1980-06-01

    The Large Aspect Ratio Tokamak Study (LARTS) at Oak Ridge National Laboratory (ORNL) investigated the potential for producing a viable longburn tokamak reactor by enhancing the volt-second capability of the ohmic heating transformer through the use of high aspect ratio designs. The plasma physics, engineering, and economic implications of high aspect ratio tokamaks were assessed in the context of extended burn operation. Using a one-dimensional transport code plasma startup and burn parameters were addressed. The pulsed electrical power requirements for the poloidal field system, which have a major impact on reactor economics, were minimized by optimizing the startup and shutdown portions of the tokamak cycle. A representative large aspect ratio tokamak with an aspect ratio of 8 was found to achieve a burn time of 3.5 h at capital cost only approx. 25% greater than that of a moderate aspect ratio design tokamak

  6. Parametric instabilities in large plasmas

    International Nuclear Information System (INIS)

    Brambilla, Marco; Liberman, Bernardo.

    1979-01-01

    Parametric decay processes in large plasmas are considered as the linear stage of a three wave interaction (pump, sideband and beat wave) in which the amplitude of the externally excited pump is sufficiently large to neglect pump depletion to first order, yet sufficiently small to allow a linearized treatment of the pump propagation to zeroth order. The coupling coefficients are then obtained from an iterative solution of Vlasov equation, and a compact expression is derived, in which the multiple series over Bessel functions is explicitly summed. Even in the limit of a very long wavelength pump, the dispersion relation obtained in this way does not coincide with the one obtained using the well-known ''dipole'' approximation, unless both the sideband and beat wave are resonant modes of the plasma. An analysis of the origin of this discrepancy allows us to conclude that ''quasimodes'' (evanescent waves driven absolutely unstable by the pump) are more correctly described by the iterative approach

  7. Plasma diagnostics on large tokamaks

    International Nuclear Information System (INIS)

    Orlinskij, D.V.; Magyar, G.

    1988-01-01

    The main tasks of the large tokamaks which are under construction (T-15 and Tore Supra) and of those which have already been built (TFTR, JET, JT-60 and DIII-D) together with their design features which are relevant to plasma diagnostics are briefly discussed. The structural features and principal characteristics of the diagnostic systems being developed or already being used on these devices are also examined. The different diagnostic methods are described according to the physical quantities to be measured: electric and magnetic diagnostics, measurements of electron density, electron temperature, the ion components of the plasma, radiation loss measurements, spectroscopy of impurities, edge diagnostics and study of plasma stability. The main parameters of the various diagnostic systems used on the six large tokamaks are summarized in tables. (author). 351 refs, 44 figs, 22 tabs

  8. Foam rheology at large deformation

    Science.gov (United States)

    Géminard, J.-C.; Pastenes, J. C.; Melo, F.

    2018-04-01

    Large deformations are prone to cause irreversible changes in materials structure, generally leading to either material hardening or softening. Aqueous foam is a metastable disordered structure of densely packed gas bubbles. We report on the mechanical response of a foam layer subjected to quasistatic periodic shear at large amplitude. We observe that, upon increasing shear, the shear stress follows a universal curve that is nearly exponential and tends to an asymptotic stress value interpreted as the critical yield stress at which the foam structure is completely remodeled. Relevant trends of the foam mechanical response to cycling are mathematically reproduced through a simple law accounting for the amount of plastic deformation upon increasing stress. This view provides a natural interpretation to stress hardening in foams, demonstrating that plastic effects are present in this material even for minute deformation.

  9. Physics with large extra dimensions

    CERN Document Server

    Antoniadis, Ignatios

    2004-01-01

    The recent understanding of string theory opens the possibility that the string scale can be as low as a few TeV. The apparent weakness of gravitational interactions can then be accounted by the existence of large internal dimensions, in the submillimeter region. Furthermore, our world must be confined to live on a brane transverse to these large dimensions, with which it interacts only gravitationally. In my lecture, I describe briefly this scenario which gives a new theoretical framework for solving the gauge hierarchy problem and the unification of all interactions. I also discuss its main properties and implications for observations at both future particle colliders, and in non-accelerator gravity experiments. Such effects are for instance the production of Kaluza-Klein resonances, graviton emission in the bulk of extra dimensions, and a radical change of gravitational forces in the submillimeter range.

  10. Chunking of Large Multidimensional Arrays

    Energy Technology Data Exchange (ETDEWEB)

    Rotem, Doron; Otoo, Ekow J.; Seshadri, Sridhar

    2007-02-28

    Data intensive scientific computations as well on-lineanalytical processing applications as are done on very large datasetsthat are modeled as k-dimensional arrays. The storage organization ofsuch arrays on disks is done by partitioning the large global array intofixed size hyper-rectangular sub-arrays called chunks or tiles that formthe units of data transfer between disk and memory. Typical queriesinvolve the retrieval of sub-arrays in a manner that accesses all chunksthat overlap the query results. An important metric of the storageefficiency is the expected number of chunks retrieved over all suchqueries. The question that immediately arises is "what shapes of arraychunks give the minimum expected number of chunks over a query workload?"In this paper we develop two probabilistic mathematical models of theproblem and provide exact solutions using steepest descent and geometricprogramming methods. Experimental results, using synthetic workloads onreal life data sets, show that our chunking is much more efficient thanthe existing approximate solutions.

  11. Large Extremity Peripheral Nerve Repair

    Science.gov (United States)

    2016-12-01

    These antimicrobial peptides are implicated in the resistance of epithelial surfaces to microbial colonisation and have been shown to be upregulated...be equivalent to standard autograft repair in rodent models. Outcomes have now been validated in a large animal (swine) model with 5 cm ulnar nerve...Goals of the Project Task 1– Determine mechanical properties, seal strength and resistance to biodegradation of candidate photochemical nerve wrap

  12. Community Detection for Large Graphs

    KAUST Repository

    Peng, Chengbin

    2014-05-04

    Many real world networks have inherent community structures, including social networks, transportation networks, biological networks, etc. For large scale networks with millions or billions of nodes in real-world applications, accelerating current community detection algorithms is in demand, and we present two approaches to tackle this issue -A K-core based framework that can accelerate existing community detection algorithms significantly; -A parallel inference algorithm via stochastic block models that can distribute the workload.

  13. Large floating structures technological advances

    CERN Document Server

    Wang, BT

    2015-01-01

    This book surveys key projects that have seen the construction of large floating structures or have attained detailed conceptual designs. This compilation of key floating structures in a single volume captures the innovative features that mark the technological advances made in this field of engineering, and will provide a useful reference for ideas, analysis, design, and construction of these unique and emerging urban projects to offshore and marine engineers, urban planners, architects and students.

  14. Visualising large hierarchies with Flextree

    Science.gov (United States)

    Song, Hongzhi; Curran, Edwin P.; Sterritt, Roy

    2003-05-01

    One of the main tasks in Information Visualisation research is creating visual tools to facilitate human understanding of large and complex information spaces. Hierarchies, being a good mechanism in organising such information, are ubiquitous. Although much research effort has been spent on finding useful representations for hierarchies, visualising large hierarchies is still a difficult topic. One of the difficulties is how to show both tructure and node content information in one view. Another is how to achieve multiple foci in a focus+context visualisation. This paper describes a novel hierarchy visualisation technique called FlexTree to address these problems. It contains some important features that have not been exploited so far. In this visualisation, a profile or contour unique to the hierarchy being visualised can be gained in a histogram-like layout. A normalised view of a common attribute of all nodes can be acquired, and selection of this attribute is controllable by the user. Multiple foci are consistently accessible within a global context through interaction. Furthermore it can handle a large hierarchy that contains several thousand nodes in a PC environment. In addition results from an informal evaluation are also presented.

  15. The large sample size fallacy.

    Science.gov (United States)

    Lantz, Björn

    2013-06-01

    Significance in the statistical sense has little to do with significance in the common practical sense. Statistical significance is a necessary but not a sufficient condition for practical significance. Hence, results that are extremely statistically significant may be highly nonsignificant in practice. The degree of practical significance is generally determined by the size of the observed effect, not the p-value. The results of studies based on large samples are often characterized by extreme statistical significance despite small or even trivial effect sizes. Interpreting such results as significant in practice without further analysis is referred to as the large sample size fallacy in this article. The aim of this article is to explore the relevance of the large sample size fallacy in contemporary nursing research. Relatively few nursing articles display explicit measures of observed effect sizes or include a qualitative discussion of observed effect sizes. Statistical significance is often treated as an end in itself. Effect sizes should generally be calculated and presented along with p-values for statistically significant results, and observed effect sizes should be discussed qualitatively through direct and explicit comparisons with the effects in related literature. © 2012 Nordic College of Caring Science.

  16. Large nuclear steam turbine plants

    International Nuclear Information System (INIS)

    Urushidani, Haruo; Moriya, Shin-ichi; Tsuji, Kunio; Fujita, Isao; Ebata, Sakae; Nagai, Yoji.

    1986-01-01

    The technical development of the large capacity steam turbines for ABWR plants was partially completed, and that in progress is expected to be completed soon. In this report, the outline of those new technologies is described. As the technologies for increasing the capacity and heightening the efficiency, 52 in long blades and moisture separating heaters are explained. Besides, in the large bore butterfly valves developed for making the layout compact, the effect of thermal efficiency rise due to the reduction of pressure loss can be expected. As the new technology on the system side, the simplification of the turbine system and the effect of heightening the thermal efficiency by high pressure and low pressure drain pumping-up method based on the recent improvement of feed water quality are discussed. As for nuclear steam turbines, the actual records of performance of 1100 MW class, the largest output at present, have been obtained, and as a next large capacity machine, the development of a steam turbine of 1300 MWe class for an ABWR plant is in progress. It can be expected that by the introduction of those new technologies, the plants having high economical efficiency are realized. (Kako, I.)

  17. Perturbation theory in large order

    International Nuclear Information System (INIS)

    Bender, C.M.

    1978-01-01

    For many quantum mechanical models, the behavior of perturbation theory in large order is strikingly simple. For example, in the quantum anharmonic oscillator, which is defined by -y'' + (x 2 /4 + ex 4 /4 - E) y = 0, y ( +- infinity) = 0, the perturbation coefficients, A/sub n/, in the expansion for the ground-state energy, E(ground state) approx. EPSILON/sub n = 0//sup infinity/ A/sub n/epsilon/sup n/, simplify dramatically as n → infinity: A/sub n/ approx. (6/π 3 )/sup 1/2/(-3)/sup n/GAMMA(n + 1/2). Methods of applied mathematics are used to investigate the nature of perturbation theory in quantum mechanics and show that its large-order behavior is determined by the semiclassical content of the theory. In quantum field theory the perturbation coefficients are computed by summing Feynman graphs. A statistical procedure in a simple lambda phi 4 model for summing the set of all graphs as the number of vertices → infinity is presented. Finally, the connection between the large-order behavior of perturbation theory in quantum electrodynamics and the value of α, the charge on the electron, is discussed. 7 figures

  18. Foreshock occurrence before large earthquakes

    Science.gov (United States)

    Reasenberg, P.A.

    1999-01-01

    Rates of foreshock occurrence involving shallow M ??? 6 and M ??? 7 mainshocks and M ??? 5 foreshocks were measured in two worldwide catalogs over ???20-year intervals. The overall rates observed are similar to ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide rates were compared to a generic model of earthquake clustering based on patterns of small and moderate aftershocks in California. The aftershock model was extended to the case of moderate foreshocks preceding large mainshocks. Overall, the observed worldwide foreshock rates exceed the extended California generic model by a factor of ???2. Significant differences in foreshock rate were found among subsets of earthquakes defined by their focal mechanism and tectonic region, with the rate before thrust events higher and the rate before strike-slip events lower than the worldwide average. Among the thrust events, a large majority, composed of events located in shallow subduction zones, had a high foreshock rate, while a minority, located in continental thrust belts, had a low rate. These differences may explain why previous surveys have found low foreshock rates among thrust events in California (especially southern California), while the worldwide observations suggests the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low rate apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich. If this is so, then the California generic model may significantly underestimate the conditional probability for a very large (M ??? 8) earthquake following a potential (M ??? 7) foreshock in Cascadia. The magnitude differences among the identified foreshock-mainshock pairs in the Harvard catalog are consistent with a uniform

  19. Large number discrimination by mosquitofish.

    Directory of Open Access Journals (Sweden)

    Christian Agrillo

    Full Text Available BACKGROUND: Recent studies have demonstrated that fish display rudimentary numerical abilities similar to those observed in mammals and birds. The mechanisms underlying the discrimination of small quantities (<4 were recently investigated while, to date, no study has examined the discrimination of large numerosities in fish. METHODOLOGY/PRINCIPAL FINDINGS: Subjects were trained to discriminate between two sets of small geometric figures using social reinforcement. In the first experiment mosquitofish were required to discriminate 4 from 8 objects with or without experimental control of the continuous variables that co-vary with number (area, space, density, total luminance. Results showed that fish can use the sole numerical information to compare quantities but that they preferentially use cumulative surface area as a proxy of the number when this information is available. A second experiment investigated the influence of the total number of elements to discriminate large quantities. Fish proved to be able to discriminate up to 100 vs. 200 objects, without showing any significant decrease in accuracy compared with the 4 vs. 8 discrimination. The third experiment investigated the influence of the ratio between the numerosities. Performance was found to decrease when decreasing the numerical distance. Fish were able to discriminate numbers when ratios were 1:2 or 2:3 but not when the ratio was 3:4. The performance of a sample of undergraduate students, tested non-verbally using the same sets of stimuli, largely overlapped that of fish. CONCLUSIONS/SIGNIFICANCE: Fish are able to use pure numerical information when discriminating between quantities larger than 4 units. As observed in human and non-human primates, the numerical system of fish appears to have virtually no upper limit while the numerical ratio has a clear effect on performance. These similarities further reinforce the view of a common origin of non-verbal numerical systems in all

  20. Radiosurgery for Large Brain Metastases

    International Nuclear Information System (INIS)

    Han, Jung Ho; Kim, Dong Gyu; Chung, Hyun-Tai; Paek, Sun Ha; Park, Chul-Kee; Jung, Hee-Won

    2012-01-01

    Purpose: To determine the efficacy and safety of radiosurgery in patients with large brain metastases treated with radiosurgery. Patients and Methods: Eighty patients with large brain metastases (>14 cm 3 ) were treated with radiosurgery between 1998 and 2009. The mean age was 59 ± 11 years, and 49 (61.3%) were men. Neurologic symptoms were identified in 77 patients (96.3%), and 30 (37.5%) exhibited a dependent functional status. The primary disease was under control in 36 patients (45.0%), and 44 (55.0%) had a single lesion. The mean tumor volume was 22.4 ± 8.8 cm 3 , and the mean marginal dose prescribed was 13.8 ± 2.2 Gy. Results: The median survival time from radiosurgery was 7.9 months (95% confidence interval [CI], 5.343–10.46), and the 1-year survival rate was 39.2%. Functional improvement within 1–4 months or the maintenance of the initial independent status was observed in 48 (60.0%) and 20 (25.0%) patients after radiosurgery, respectively. Control of the primary disease, a marginal dose of ≥11 Gy, and a tumor volume ≥26 cm 3 were significantly associated with overall survival (hazard ratio, 0.479; p = .018; 95% CI, 0.261–0.880; hazard ratio, 0.350; p = .004; 95% CI, 0.171–0.718; hazard ratio, 2.307; p = .006; 95% CI, 1.274–4.180, respectively). Unacceptable radiation-related toxicities (Radiation Toxicity Oncology Group central nervous system toxicity Grade 3, 4, and 5 in 7, 6, and 2 patients, respectively) developed in 15 patients (18.8%). Conclusion: Radiosurgery seems to have a comparable efficacy with surgery for large brain metastases. However, the rate of radiation-related toxicities after radiosurgery should be considered when deciding on a treatment modality.

  1. Large-bore pipe decontamination

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system

  2. The IEA Large Coil Task

    International Nuclear Information System (INIS)

    Beard, D.S.; Klose, W.; Shimamoto, S.; Vecsey, G.

    1988-01-01

    A multinational program of cooperative research, development, demonstrations, and exchanges of information on superconducting magnets for fusion was initiated in 1977 under an IEA agreement. The first major step in the development of TF magnets was called the Large Coil Task. Participants in LCT were the U.S. DOE, EURATOM, JAERI, and the Departement Federal de l'Interieur of Switzerland. The goals of LCT were to obtain experimental data, to demonstrate reliable operation of large superconducting coils, and to prove design principles and fabrication techniques being considered for the toroidal magnets of thermonuclear reactors. These goals were to be accomplished through coordinated but largely independent design, development, and construction of six test coils, followed by collaborative testing in a compact toroidal test array at fields of 8 T and higher. Under the terms of the IEA Agreement, the United States built and operated the test facility at Oak Ridge and provided three test coils. The other participants provided one coil each. Information on design and manufacturing and all test data were shared by all. The LCT team of each participant included a government laboratory and industrial partners or contractors. The last coil was completed in 1985, and the test assembly was completed in October of that year. Over the next 23 months, the six-coil array was cooled down and extensive testing was performed. Results were gratifying, as tests achieved design-point performance and well beyond. (Each coil reached a peak field of 9 T.) Experiments elucidated coil behavior, delineated limits of operability, and demonstrated coil safety. (orig./KP)

  3. Large block test status report

    International Nuclear Information System (INIS)

    Wilder, D.G.; Lin, W.; Blair, S.C.

    1997-01-01

    This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved

  4. Large volume cryogenic silicon detectors

    International Nuclear Information System (INIS)

    Braggio, C.; Boscardin, M.; Bressi, G.; Carugno, G.; Corti, D.; Galeazzi, G.; Zorzi, N.

    2009-01-01

    We present preliminary measurements for the development of a large volume silicon detector to detect low energy and low rate energy depositions. The tested detector is a one cm-thick silicon PIN diode with an active volume of 31 cm 3 , cooled to the liquid helium temperature to obtain depletion from thermally-generated free carriers. A thorough study has been done to show that effects of charge trapping during drift disappears at a bias field value of the order of 100V/cm.

  5. Large volume cryogenic silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Braggio, C. [Dipartimento di Fisica, Universita di Padova, via Marzolo 8, 35131 Padova (Italy); Boscardin, M. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy); Bressi, G. [INFN sez. di Pavia, via Bassi 6, 27100 Pavia (Italy); Carugno, G.; Corti, D. [INFN sez. di Padova, via Marzolo 8, 35131 Padova (Italy); Galeazzi, G. [INFN lab. naz. Legnaro, viale dell' Universita 2, 35020 Legnaro (Italy); Zorzi, N. [Fondazione Bruno Kessler (FBK), via Sommarive 18, I-38100 Povo (Italy)

    2009-12-15

    We present preliminary measurements for the development of a large volume silicon detector to detect low energy and low rate energy depositions. The tested detector is a one cm-thick silicon PIN diode with an active volume of 31 cm{sup 3}, cooled to the liquid helium temperature to obtain depletion from thermally-generated free carriers. A thorough study has been done to show that effects of charge trapping during drift disappears at a bias field value of the order of 100V/cm.

  6. Large area and flexible electronics

    CERN Document Server

    Caironi, Mario

    2015-01-01

    From materials to applications, this ready reference covers the entire value chain from fundamentals via processing right up to devices, presenting different approaches to large-area electronics, thus enabling readers to compare materials, properties and performance.Divided into two parts, the first focuses on the materials used for the electronic functionality, covering organic and inorganic semiconductors, including vacuum and solution-processed metal-oxide semiconductors, nanomembranes and nanocrystals, as well as conductors and insulators. The second part reviews the devices and applicatio

  7. Japanese large-scale interferometers

    CERN Document Server

    Kuroda, K; Miyoki, S; Ishizuka, H; Taylor, C T; Yamamoto, K; Miyakawa, O; Fujimoto, M K; Kawamura, S; Takahashi, R; Yamazaki, T; Arai, K; Tatsumi, D; Ueda, A; Fukushima, M; Sato, S; Shintomi, T; Yamamoto, A; Suzuki, T; Saitô, Y; Haruyama, T; Sato, N; Higashi, Y; Uchiyama, T; Tomaru, T; Tsubono, K; Ando, M; Takamori, A; Numata, K; Ueda, K I; Yoneda, H; Nakagawa, K; Musha, M; Mio, N; Moriwaki, S; Somiya, K; Araya, A; Kanda, N; Telada, S; Sasaki, M; Tagoshi, H; Nakamura, T; Tanaka, T; Ohara, K

    2002-01-01

    The objective of the TAMA 300 interferometer was to develop advanced technologies for kilometre scale interferometers and to observe gravitational wave events in nearby galaxies. It was designed as a power-recycled Fabry-Perot-Michelson interferometer and was intended as a step towards a final interferometer in Japan. The present successful status of TAMA is presented. TAMA forms a basis for LCGT (large-scale cryogenic gravitational wave telescope), a 3 km scale cryogenic interferometer to be built in the Kamioka mine in Japan, implementing cryogenic mirror techniques. The plan of LCGT is schematically described along with its associated R and D.

  8. Large spin systematics in CFT

    Energy Technology Data Exchange (ETDEWEB)

    Alday, Luis F.; Bissi, Agnese; Łukowski, Tomasz [Mathematical Institute, University of Oxford,Andrew Wiles Building, Radcliffe Observatory Quarter,Woodstock Road, Oxford, OX2 6GG (United Kingdom)

    2015-11-16

    Using conformal field theory (CFT) arguments we derive an infinite number of constraints on the large spin expansion of the anomalous dimensions and structure constants of higher spin operators. These arguments rely only on analyticity, unitarity, crossing-symmetry and the structure of the conformal partial wave expansion. We obtain results for both, perturbative CFT to all order in the perturbation parameter, as well as non-perturbatively. For the case of conformal gauge theories this provides a proof of the reciprocity principle to all orders in perturbation theory and provides a new “reciprocity' principle for structure constants. We argue that these results extend also to non-conformal theories.

  9. Large spin systematics in CFT

    International Nuclear Information System (INIS)

    Alday, Luis F.; Bissi, Agnese; Łukowski, Tomasz

    2015-01-01

    Using conformal field theory (CFT) arguments we derive an infinite number of constraints on the large spin expansion of the anomalous dimensions and structure constants of higher spin operators. These arguments rely only on analyticity, unitarity, crossing-symmetry and the structure of the conformal partial wave expansion. We obtain results for both, perturbative CFT to all order in the perturbation parameter, as well as non-perturbatively. For the case of conformal gauge theories this provides a proof of the reciprocity principle to all orders in perturbation theory and provides a new “reciprocity' principle for structure constants. We argue that these results extend also to non-conformal theories.

  10. Quick Mining of Isomorphic Exact Large Patterns from Large Graphs

    KAUST Repository

    Almasri, Islam

    2014-12-01

    The applications of the sub graph isomorphism search are growing with the growing number of areas that model their systems using graphs or networks. Specifically, many biological systems, such as protein interaction networks, molecular structures and protein contact maps, are modeled as graphs. The sub graph isomorphism search is concerned with finding all sub graphs that are isomorphic to a relevant query graph, the existence of such sub graphs can reflect on the characteristics of the modeled system. The most computationally expensive step in the search for isomorphic sub graphs is the backtracking algorithm that traverses the nodes of the target graph. In this paper, we propose a pruning approach that is inspired by the minimum remaining value heuristic that achieves greater scalability over large query and target graphs. Our testing on various biological networks shows that performance enhancement of our approach over existing state-of-the-art approaches varies between 6x and 53x. © 2014 IEEE.

  11. Quick Mining of Isomorphic Exact Large Patterns from Large Graphs

    KAUST Repository

    Almasri, Islam; Gao, Xin; Fedoroff, Nina V.

    2014-01-01

    The applications of the sub graph isomorphism search are growing with the growing number of areas that model their systems using graphs or networks. Specifically, many biological systems, such as protein interaction networks, molecular structures and protein contact maps, are modeled as graphs. The sub graph isomorphism search is concerned with finding all sub graphs that are isomorphic to a relevant query graph, the existence of such sub graphs can reflect on the characteristics of the modeled system. The most computationally expensive step in the search for isomorphic sub graphs is the backtracking algorithm that traverses the nodes of the target graph. In this paper, we propose a pruning approach that is inspired by the minimum remaining value heuristic that achieves greater scalability over large query and target graphs. Our testing on various biological networks shows that performance enhancement of our approach over existing state-of-the-art approaches varies between 6x and 53x. © 2014 IEEE.

  12. Quantum chromodynamics at large distances

    International Nuclear Information System (INIS)

    Arbuzov, B.A.

    1987-01-01

    Properties of QCD at large distances are considered in the framework of traditional quantum field theory. An investigation of asymptotic behaviour of lower Green functions in QCD is the starting point of the approach. The recent works are reviewed which confirm the singular infrared behaviour of gluon propagator M 2 /(k 2 ) 2 at least under some gauge conditions. A special covariant gauge comes out to be the most suitable for description of infrared region due to absence of ghost contributions to infrared asymptotics of Green functions. Solutions of Schwinger-Dyson equation for quark propagator are obtained in this special gauge and are shown to possess desirable properties: spontaneous breaking of chiral invariance and nonperturbative character. The infrared asymptotics of lower Green functions are used for calculation of vacuum expectation values of gluon and quark fields. These vacuum expectation values are obtained in a good agreement with the corresponding phenomenological values which are needed in the method of sum rules in QCD, that confirms adequacy of the infrared region description. The consideration of a behaviour of QCD at large distances leads to the conclusion that at contemporary stage of theory development one may consider two possibilities. The first one is the well-known confinement hypothesis and the second one is called incomplete confinement and stipulates for open color to be observable. Possible manifestations of incomplete confinement are discussed

  13. Large scale cluster computing workshop

    International Nuclear Information System (INIS)

    Dane Skow; Alan Silverman

    2002-01-01

    Recent revolutions in computer hardware and software technologies have paved the way for the large-scale deployment of clusters of commodity computers to address problems heretofore the domain of tightly coupled SMP processors. Near term projects within High Energy Physics and other computing communities will deploy clusters of scale 1000s of processors and be used by 100s to 1000s of independent users. This will expand the reach in both dimensions by an order of magnitude from the current successful production facilities. The goals of this workshop were: (1) to determine what tools exist which can scale up to the cluster sizes foreseen for the next generation of HENP experiments (several thousand nodes) and by implication to identify areas where some investment of money or effort is likely to be needed. (2) To compare and record experimences gained with such tools. (3) To produce a practical guide to all stages of planning, installing, building and operating a large computing cluster in HENP. (4) To identify and connect groups with similar interest within HENP and the larger clustering community

  14. Nonlinear electrokinetics at large voltages

    Energy Technology Data Exchange (ETDEWEB)

    Bazant, Martin Z [Department of Chemical Engineering and Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Sabri Kilic, Mustafa; Ajdari, Armand [Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Storey, Brian D [Franklin W Olin College of Engineering, Needham, MA 02492 (United States)], E-mail: bazant@mit.edu

    2009-07-15

    The classical theory of electrokinetic phenomena assumes a dilute solution of point-like ions in chemical equilibrium with a surface whose double-layer voltage is of order the thermal voltage, k{sub B}T/e=25 mV. In nonlinear 'induced-charge' electrokinetic phenomena, such as ac electro-osmosis, several volts {approx}100k{sub B}T/e are applied to the double layer, and the theory breaks down and cannot explain many observed features. We argue that, under such a large voltage, counterions 'condense' near the surface, even for dilute bulk solutions. Based on simple models, we predict that the double-layer capacitance decreases and the electro-osmotic mobility saturates at large voltages, due to steric repulsion and increased viscosity of the condensed layer, respectively. The former suffices to explain observed high-frequency flow reversal in ac electro-osmosis; the latter leads to a salt concentration dependence of induced-charge flows comparable to experiments, although a complete theory is still lacking.

  15. Large shaft development test plan

    International Nuclear Information System (INIS)

    Krug, A.D.

    1984-03-01

    This test plan proposes the conduct of a large shaft development test at the Hanford site in support of the repository development program. The purpose and objective of the test plan is to obtain the information necessary to establish feasibility and to predict the performance of the drilling system used to drill large diameter shafts. The test plan is based upon drilling a 20 ft diameter shaft to a depth of 1,000 feet. The test plan specifies series of tests to evaluate the performance of the downhole assembly, the performance of the rig, and the ability of the system to cope with geologic hazards. The quality of the hole produced will also be determined. This test plan is considered to be preliminary in that it was prepared as input for the decision to determine if development testing is required in this area. Should the decision be made to proceed with development testing, this test plan shall be updated and revised. 6 refs., 2 figs., 3 tabs

  16. How Large Asexual Populations Adapt

    Science.gov (United States)

    Desai, Michael

    2007-03-01

    We often think of beneficial mutations as being rare, and of adaptation as a sequence of selected substitutions: a beneficial mutation occurs, spreads through a population in a selective sweep, then later another beneficial mutation occurs, and so on. This simple picture is the basis for much of our intuition about adaptive evolution, and underlies a number of practical techniques for analyzing sequence data. Yet many large and mostly asexual populations -- including a wide variety of unicellular organisms and viruses -- live in a very different world. In these populations, beneficial mutations are common, and frequently interfere or cooperate with one another as they all attempt to sweep simultaneously. This radically changes the way these populations adapt: rather than an orderly sequence of selective sweeps, evolution is a constant swarm of competing and interfering mutations. I will describe some aspects of these dynamics, including why large asexual populations cannot evolve very quickly and the character of the diversity they maintain. I will explain how this changes our expectations of sequence data, how sex can help a population adapt, and the potential role of ``mutator'' phenotypes with abnormally high mutation rates. Finally, I will discuss comparisons of these predictions with evolution experiments in laboratory yeast populations.

  17. Creating Large Scale Database Servers

    International Nuclear Information System (INIS)

    Becla, Jacek

    2001-01-01

    The BaBar experiment at the Stanford Linear Accelerator Center (SLAC) is designed to perform a high precision investigation of the decays of the B-meson produced from electron-positron interactions. The experiment, started in May 1999, will generate approximately 300TB/year of data for 10 years. All of the data will reside in Objectivity databases accessible via the Advanced Multi-threaded Server (AMS). To date, over 70TB of data have been placed in Objectivity/DB, making it one of the largest databases in the world. Providing access to such a large quantity of data through a database server is a daunting task. A full-scale testbed environment had to be developed to tune various software parameters and a fundamental change had to occur in the AMS architecture to allow it to scale past several hundred terabytes of data. Additionally, several protocol extensions had to be implemented to provide practical access to large quantities of data. This paper will describe the design of the database and the changes that we needed to make in the AMS for scalability reasons and how the lessons we learned would be applicable to virtually any kind of database server seeking to operate in the Petabyte region

  18. Creating Large Scale Database Servers

    Energy Technology Data Exchange (ETDEWEB)

    Becla, Jacek

    2001-12-14

    The BaBar experiment at the Stanford Linear Accelerator Center (SLAC) is designed to perform a high precision investigation of the decays of the B-meson produced from electron-positron interactions. The experiment, started in May 1999, will generate approximately 300TB/year of data for 10 years. All of the data will reside in Objectivity databases accessible via the Advanced Multi-threaded Server (AMS). To date, over 70TB of data have been placed in Objectivity/DB, making it one of the largest databases in the world. Providing access to such a large quantity of data through a database server is a daunting task. A full-scale testbed environment had to be developed to tune various software parameters and a fundamental change had to occur in the AMS architecture to allow it to scale past several hundred terabytes of data. Additionally, several protocol extensions had to be implemented to provide practical access to large quantities of data. This paper will describe the design of the database and the changes that we needed to make in the AMS for scalability reasons and how the lessons we learned would be applicable to virtually any kind of database server seeking to operate in the Petabyte region.

  19. Histotripsy Liquefaction of Large Hematomas.

    Science.gov (United States)

    Khokhlova, Tatiana D; Monsky, Wayne L; Haider, Yasser A; Maxwell, Adam D; Wang, Yak-Nam; Matula, Thomas J

    2016-07-01

    Intra- and extra-muscular hematomas result from repetitive injury as well as sharp and blunt limb trauma. The clinical consequences can be serious, including debilitating pain and functional deficit. There are currently no short-term treatment options for large hematomas, only lengthy conservative treatment. The goal of this work was to evaluate the feasibility of a high intensity focused ultrasound (HIFU)-based technique, termed histotripsy, for rapid (within a clinically relevant timeframe of 15-20 min) liquefaction of large volume (up to 20 mL) extra-vascular hematomas for subsequent fine-needle aspiration. Experiments were performed using in vitro extravascular hematoma phantoms-fresh bovine blood poured into 50 mL molds and allowed to clot. The resulting phantoms were treated by boiling histotripsy (BH), cavitation histotripsy (CH) or a combination in a degassed water tank under ultrasound guidance. Two different transducers operating at 1 MHz and 1.5 MHz with f-number = 1 were used. The liquefied lysate was aspirated and analyzed by histology and sized in a Coulter Counter. The peak instantaneous power to achieve BH was lower than (at 1.5 MHz) or equal to (at 1 MHz) that which was required to initiate CH. Under the same exposure duration, BH-induced cavities were one and a half to two times larger than the CH-induced cavities, but the CH-induced cavities were more regularly shaped, facilitating easier aspiration. The lysates contained a small amount of debris larger than 70 μm, and 99% of particulates were smaller than 10 μm. A combination treatment of BH (for initial debulking) and CH (for liquefaction of small residual fragments) yielded 20 mL of lysate within 17.5 minutes of treatment and was found to be most optimal for liquefaction of large extravascular hematomas. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  20. Book review: Large igneous provinces

    Science.gov (United States)

    du Bray, Edward A.

    2015-01-01

    This book presents a comprehensive compilation of all aspects of large igneous provinces (LIPs). Published in 2014, the book is now the definitive source of information on the petrogenesis of this type of globally important, voluminous magmatic activity. In the first few pages, LIPs are characterized as magmatic provinces with areal extents >0.1 Mkm2 that are dominated by mafic magmas emplaced or erupted in intraplate settings during relatively short (1–5 m.y.) time intervals. Given these parameters, particularly areal extent, LIPs clearly represent significant contributions to global geologic evolution through time. This point is underscored, also in the introductory chapter, by a series of figures that aptly characterize the global time-space distribution of LIPs; an accompanying, particularly useful table identifies individual LIPs, quantifies their basic characteristics, and enumerates pertinent references. Accordingly, this compilation is a welcome addition to the geologic literature.

  1. Large errors and severe conditions

    CERN Document Server

    Smith, D L; Van Wormer, L A

    2002-01-01

    Physical parameters that can assume real-number values over a continuous range are generally represented by inherently positive random variables. However, if the uncertainties in these parameters are significant (large errors), conventional means of representing and manipulating the associated variables can lead to erroneous results. Instead, all analyses involving them must be conducted in a probabilistic framework. Several issues must be considered: First, non-linear functional relations between primary and derived variables may lead to significant 'error amplification' (severe conditions). Second, the commonly used normal (Gaussian) probability distribution must be replaced by a more appropriate function that avoids the occurrence of negative sampling results. Third, both primary random variables and those derived through well-defined functions must be dealt with entirely in terms of their probability distributions. Parameter 'values' and 'errors' should be interpreted as specific moments of these probabil...

  2. Large shaft development test plan

    International Nuclear Information System (INIS)

    Krug, A.D.

    1984-03-01

    This test plan proposes the conduct of shaft liner tests as part of the large shaft development test proposed for the Hanford Site in support of the repository development program. The objectives of these tests are to develop techniques for measuring liner alignment (straightness), both construction assembly alignment and downhole cumulative alignment, and to assess the alignment information as a real time feedback to aid the installation procedure. The test plan is based upon installing a 16 foot ID shaft liner into a 20 foot diameter shaft to a depth of 1000 feet. This test plan is considered to be preliminary in that it was prepared as input for the decision to determine if development testing is required in this area. Should the decision be made to proceed with development testing, this test plan shall be updated and revised. 6 refs., 2 figs

  3. Large scale biomimetic membrane arrays

    DEFF Research Database (Denmark)

    Hansen, Jesper Søndergaard; Perry, Mark; Vogel, Jörg

    2009-01-01

    To establish planar biomimetic membranes across large scale partition aperture arrays, we created a disposable single-use horizontal chamber design that supports combined optical-electrical measurements. Functional lipid bilayers could easily and efficiently be established across CO2 laser micro......-structured 8 x 8 aperture partition arrays with average aperture diameters of 301 +/- 5 mu m. We addressed the electro-physical properties of the lipid bilayers established across the micro-structured scaffold arrays by controllable reconstitution of biotechnological and physiological relevant membrane...... peptides and proteins. Next, we tested the scalability of the biomimetic membrane design by establishing lipid bilayers in rectangular 24 x 24 and hexagonal 24 x 27 aperture arrays, respectively. The results presented show that the design is suitable for further developments of sensitive biosensor assays...

  4. Model of large pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

    2006-08-21

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

  5. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  6. Large-scale solar heating

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    Solar heating market is growing in many European countries and annually installed collector area has exceeded one million square meters. There are dozens of collector manufacturers and hundreds of firms making solar heating installations in Europe. One tendency in solar heating is towards larger systems. These can be roof integrated, consisting of some tens or hundreds of square meters of collectors, or they can be larger centralized solar district heating plants consisting of a few thousand square meters of collectors. The increase of size can reduce the specific investments of solar heating systems, because e.g. the costs of some components (controllers, pumps, and pipes), planning and installation can be smaller in larger systems. The solar heat output can also be higher in large systems, because more advanced technique is economically viable

  7. Large aspect ratio tokamak study

    International Nuclear Information System (INIS)

    Reid, R.L.; Holmes, J.A.; Houlberg, W.A.; Peng, Y.K.M.; Strickler, D.J.; Brown, T.G.; Sardella, C.; Wiseman, G.W.

    1979-01-01

    The Large Aspect Ratio Tokamak Study (LARTS) investigated the potential for producing a viable long burn tokamak reactor through enhanced volt-second capability of the ohmic heating transformer by employing high aspect ratio designs. The plasma physics, engineering, and economic implications of high aspect ratio tokamaks were accessed in the context of extended burn operation. Plasma startup and burn parameters were addressed using a one-dimensional transport code. The pulsed electrical power requirements for the poloidal field system, which have a major impact on reactor economics, were minimized by optimizing the field in the ohmic heating coil and the wave shape of the ohmic heating discharge. A high aspect ratio reference reactor was chosen and configured

  8. LARGE BLOCK TEST STATUS REPORT

    International Nuclear Information System (INIS)

    D.G. WILDER, W. LIN, S.C. BLAIR, T. BUSCHECK, R.C. CARLSON, K. LEE, A. MEIKE, A.L. RAMIREZ, J.L. WAGONER, AND J. WANG

    1997-01-01

    This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved. The United States Department of Energy (DOE) is investigatinq the suitability of Yucca Mountain (YM) as a potential site for the nation's first high-level nuclear waste repository. As shown in Fig. 1-1, the site is located about 120 km northwest of Las Vegas, Nevada, in an area of uninhabited desert

  9. Large Aperture Electrostatic Dust Detector

    International Nuclear Information System (INIS)

    Skinner, C.H.; Hensley, R.; Roquemore, A.L.

    2007-01-01

    Diagnosis and management of dust inventories generated in next-step magnetic fusion devices is necessary for their safe operation. A novel electrostatic dust detector, based on a fine grid of interlocking circuit traces biased to 30 or 50 v has been developed for the detection of dust particles on remote surfaces in air and vacuum environments. Impinging dust particles create a temporary short circuit and the resulting current pulse is recorded by counting electronics. Up to 90% of the particles are ejected from the grid or vaporized suggesting the device may be useful for controlling dust inventories. We report measurements of the sensitivity of a large area (5x5 cm) detector to microgram quantities of dust particles and review its applications to contemporary tokamaks and ITER.

  10. Conference on Large Scale Optimization

    CERN Document Server

    Hearn, D; Pardalos, P

    1994-01-01

    On February 15-17, 1993, a conference on Large Scale Optimization, hosted by the Center for Applied Optimization, was held at the University of Florida. The con­ ference was supported by the National Science Foundation, the U. S. Army Research Office, and the University of Florida, with endorsements from SIAM, MPS, ORSA and IMACS. Forty one invited speakers presented papers on mathematical program­ ming and optimal control topics with an emphasis on algorithm development, real world applications and numerical results. Participants from Canada, Japan, Sweden, The Netherlands, Germany, Belgium, Greece, and Denmark gave the meeting an important international component. At­ tendees also included representatives from IBM, American Airlines, US Air, United Parcel Serice, AT & T Bell Labs, Thinking Machines, Army High Performance Com­ puting Research Center, and Argonne National Laboratory. In addition, the NSF sponsored attendance of thirteen graduate students from universities in the United States and abro...

  11. Large scale nuclear structure studies

    International Nuclear Information System (INIS)

    Faessler, A.

    1985-01-01

    Results of large scale nuclear structure studies are reported. The starting point is the Hartree-Fock-Bogoliubov solution with angular momentum and proton and neutron number projection after variation. This model for number and spin projected two-quasiparticle excitations with realistic forces yields in sd-shell nuclei similar good results as the 'exact' shell-model calculations. Here the authors present results for a pf-shell nucleus 46 Ti and results for the A=130 mass region where they studied 58 different nuclei with the same single-particle energies and the same effective force derived from a meson exchange potential. They carried out a Hartree-Fock-Bogoliubov variation after mean field projection in realistic model spaces. In this way, they determine for each yrast state the optimal mean Hartree-Fock-Bogoliubov field. They apply this method to 130 Ce and 128 Ba using the same effective nucleon-nucleon interaction. (Auth.)

  12. Analysis of large urban fires

    International Nuclear Information System (INIS)

    Kang, S.W.; Reitter, T.A.; Takata, A.N.

    1984-11-01

    Fires in urban areas caused by a nuclear burst are analyzed as a first step towards determining their smoke-generation chacteristics, which may have grave implications for global-scale climatic consequences. A chain of events and their component processes which would follow a nuclear attack are described. A numerical code is currently being developed to calculate ultimately the smoke production rate for a given attack scenario. Available models for most of the processes are incorporated into the code. Sample calculations of urban fire-development history performed in the code for an idealized uniform city are presented. Preliminary results indicate the importance of the wind, thermal radiation transmission, fuel distributions, and ignition thresholds on the urban fire spread characteristics. Future plans are to improve the existing models and develop new ones to characterize smoke production from large urban fires. 21 references, 18 figures

  13. Large-scale river regulation

    International Nuclear Information System (INIS)

    Petts, G.

    1994-01-01

    Recent concern over human impacts on the environment has tended to focus on climatic change, desertification, destruction of tropical rain forests, and pollution. Yet large-scale water projects such as dams, reservoirs, and inter-basin transfers are among the most dramatic and extensive ways in which our environment has been, and continues to be, transformed by human action. Water running to the sea is perceived as a lost resource, floods are viewed as major hazards, and wetlands are seen as wastelands. River regulation, involving the redistribution of water in time and space, is a key concept in socio-economic development. To achieve water and food security, to develop drylands, and to prevent desertification and drought are primary aims for many countries. A second key concept is ecological sustainability. Yet the ecology of rivers and their floodplains is dependent on the natural hydrological regime, and its related biochemical and geomorphological dynamics. (Author)

  14. Large-order perturbation theory

    International Nuclear Information System (INIS)

    Wu, T.T.

    1982-01-01

    The original motivation for studying the asymptotic behavior of the coefficients of perturbation series came from quantum field theory. An overview is given of some of the attempts to understand quantum field theory beyond finite-order perturbation series. At least is the case of the Thirring model and probably in general, the full content of a relativistic quantum field theory cannot be recovered from its perturbation series. This difficulty, however, does not occur in quantum mechanics, and the anharmonic oscillator is used to illustrate the methods used in large-order perturbation theory. Two completely different methods are discussed, the first one using the WKB approximation, and a second one involving the statistical analysis of Feynman diagrams. The first one is well developed and gives detailed information about the desired asymptotic behavior, while the second one is still in its infancy and gives instead information about the distribution of vertices of the Feynman diagrams

  15. Great expectations: large wind turbines

    International Nuclear Information System (INIS)

    De Vries, E.

    2001-01-01

    This article focuses on wind turbine product development, and traces the background to wind turbines from the first generation 1.5 MW machines in 1995-6, plans for the second generation 3-5 MW class turbines to meet the expected boom in offshore wind projects, to the anticipated installation of a 4.5 MW turbine, and offshore wind projects planned for 2000-2002. The switch by the market leader Vestas to variable speed operation in 2000, the new product development and marketing strategy taken by the German Pro + Pro consultancy in their design of a 1.5 MW variable speed pitch control concept, the possible limiting of the size of turbines due to logistical difficulties, opportunities offered by air ships for large turbines, and the commissioning of offshore wind farms are discussed. Details of some 2-5 MW offshore wind turbine design specifications are tabulated

  16. Perspectives on large linear colliders

    International Nuclear Information System (INIS)

    Richter, B.

    1987-11-01

    Three main items in the design of large linear colliders are presented. The first is the interrelation of energy and luminosity requirements. These two items impose severe constraints on the accelerator builder who must design a machine to meet the needs of experimentl high energy physics rather than designing a machine for its own sake. An introduction is also given for linear collider design, concentrating on what goes on at the collision point, for still another constraint comes here from the beam-beam interaction which further restricts the choices available to the accelerator builder. The author also gives his impressions of the state of the technology available for building these kinds of machines within the next decade. The paper concludes with a brief recommendation for how we can all get on with the work faster, and hope to realize these machines sooner by working together. 10 refs., 9 figs

  17. Nuclear Energy Center Site Survey, 1975. Executive summary

    International Nuclear Information System (INIS)

    1976-01-01

    The Nuclear Energy Center Site Survey is a study of a potential alternative siting approach for nuclear power and fuel-cycle facilities, an approach that would cluster sizable groups of such facilities on a relatively small number of sites. The largest aggregation of reactors on a single site being planned today is four, and this quad is assumed (for comparative study purposes) to be the typical dispersed site by the year 2000. Three basic types of nuclear energy centers are considered: power-plant centers, consisting of 10 to 40 nuclear electric generating units of 1200-megawatt electric capacity each; fuel-cycle centers, consisting of fuel reprocessing plants, mixed-oxide fuel fabrication facilities, and radioactive waste management facilities; and combined centers, containing both power plants and fuel-cycle facilities. The results of the general site-location screening efforts are shown on a United States map that shows the locations of large areas identified as likely to contain suitable candidate sites for power NECs, on the basis of four coarse screening criteria: water resources, seismic activity, population density, and statutory excluded lands

  18. Joint studies on large CANDU

    International Nuclear Information System (INIS)

    Lee, Ikhwan; Yu, S. K. W.

    1994-01-01

    from economic, safety and strategic viewpoints. A large number of research and development programs are now in place at AECL and KAERI that will permit substantial improvements to be realized in the next generation of CANDU okabts, Furthermore, opportunities exist for engineered improvements based on the research and development in advancing the generic CANDU Technology. Final Large CANDU joint study report with technical deliverables will be issued 1994 October. Phase 2 R and D program of the joint studies will be determined this year and implemented in next year. CANDU neutron economy permits versatility in choices of fuel cycles. This allows a utility to choose fuel cycle options for lower fuelling cost, better security of supply, and ultimately for much lower spent-fuel volume, than with PWR's alone. To meet Korea's strategic requirements, CANDU should be an integral part of the electricity supply mix.

  19. Large Volcanic Rises on Venus

    Science.gov (United States)

    Smrekar, Suzanne E.; Kiefer, Walter S.; Stofan, Ellen R.

    1997-01-01

    Large volcanic rises on Venus have been interpreted as hotspots, or the surface manifestation of mantle upwelling, on the basis of their broad topographic rises, abundant volcanism, and large positive gravity anomalies. Hotspots offer an important opportunity to study the behavior of the lithosphere in response to mantle forces. In addition to the four previously known hotspots, Atla, Bell, Beta, and western Eistla Regiones, five new probable hotspots, Dione, central Eistla, eastern Eistla, Imdr, and Themis, have been identified in the Magellan radar, gravity and topography data. These nine regions exhibit a wider range of volcano-tectonic characteristics than previously recognized for venusian hotspots, and have been classified as rift-dominated (Atla, Beta), coronae-dominated (central and eastern Eistla, Themis), or volcano-dominated (Bell, Dione, western Eistla, Imdr). The apparent depths of compensation for these regions ranges from 65 to 260 km. New estimates of the elastic thickness, using the 90 deg and order spherical harmonic field, are 15-40 km at Bell Regio, and 25 km at western Eistla Regio. Phillips et al. find a value of 30 km at Atla Regio. Numerous models of lithospheric and mantle behavior have been proposed to interpret the gravity and topography signature of the hotspots, with most studies focusing on Atla or Beta Regiones. Convective models with Earth-like parameters result in estimates of the thickness of the thermal lithosphere of approximately 100 km. Models of stagnant lid convection or thermal thinning infer the thickness of the thermal lithosphere to be 300 km or more. Without additional constraints, any of the model fits are equally valid. The thinner thermal lithosphere estimates are most consistent with the volcanic and tectonic characteristics of the hotspots. Estimates of the thermal gradient based on estimates of the elastic thickness also support a relatively thin lithosphere (Phillips et al.). The advantage of larger estimates of

  20. Reviving large-scale projects

    International Nuclear Information System (INIS)

    Desiront, A.

    2003-01-01

    For the past decade, most large-scale hydro development projects in northern Quebec have been put on hold due to land disputes with First Nations. Hydroelectric projects have recently been revived following an agreement signed with Aboriginal communities in the province who recognized the need to find new sources of revenue for future generations. Many Cree are working on the project to harness the waters of the Eastmain River located in the middle of their territory. The work involves building an 890 foot long dam, 30 dikes enclosing a 603 square-km reservoir, a spillway, and a power house with 3 generating units with a total capacity of 480 MW of power for start-up in 2007. The project will require the use of 2,400 workers in total. The Cree Construction and Development Company is working on relations between Quebec's 14,000 Crees and the James Bay Energy Corporation, the subsidiary of Hydro-Quebec which is developing the project. Approximately 10 per cent of the $735-million project has been designated for the environmental component. Inspectors ensure that the project complies fully with environmental protection guidelines. Total development costs for Eastmain-1 are in the order of $2 billion of which $735 million will cover work on site and the remainder will cover generating units, transportation and financial charges. Under the treaty known as the Peace of the Braves, signed in February 2002, the Quebec government and Hydro-Quebec will pay the Cree $70 million annually for 50 years for the right to exploit hydro, mining and forest resources within their territory. The project comes at a time when electricity export volumes to the New England states are down due to growth in Quebec's domestic demand. Hydropower is a renewable and non-polluting source of energy that is one of the most acceptable forms of energy where the Kyoto Protocol is concerned. It was emphasized that large-scale hydro-electric projects are needed to provide sufficient energy to meet both

  1. Conclusions of a study for the large scale melting of radioactive steel scrap arising from the dismantling of nuclear installations

    International Nuclear Information System (INIS)

    Cross, M.T.

    1992-01-01

    This Summary Paper gives an overview of the feasibility assessment carried out by AEA Technology for the evaluation of melting as a waste conditioning method for metallic Low-Level Wastes (LLW). The assessment wa carried out on behalf of BNFL, Nuclear Electric (NE) and the Department of Energy (DEn) in a work programme started in 1987 and completed during 1990. The salient technical findings and economic arguments for the method are presented in this brief appraisal of the study

  2. Large Scale Glazed Concrete Panels

    DEFF Research Database (Denmark)

    Bache, Anja Margrethe

    2010-01-01

    Today, there is a lot of focus on concrete surface’s aesthitic potential, both globally and locally. World famous architects such as Herzog De Meuron, Zaha Hadid, Richard Meyer and David Chippenfield challenge the exposure of concrete in their architecture. At home, this trend can be seen...... in the crinkly façade of DR-Byen (the domicile of the Danish Broadcasting Company) by architect Jean Nouvel and Zaha Hadid’s Ordrupgård’s black curved smooth concrete surfaces. Furthermore, one can point to initiatives such as “Synlig beton” (visible concrete) that can be seen on the website www.......synligbeton.dk and spæncom’s aesthetic relief effects by the designer Line Kramhøft (www.spaencom.com). It is my hope that the research-development project “Lasting large scale glazed concrete formwork,” I am working on at DTU, department of Architectural Engineering will be able to complement these. It is a project where I...

  3. The Large Hadron Collider project

    CERN Document Server

    Maiani, Luciano

    1999-01-01

    Knowledge of the fundamental constituents of matter has greatly advanced, over the last decades. The standard theory of fundamental interactions presents us with a theoretically sound picture, which describes with great accuracy known physical phenomena on most diverse energy and distance scales. These range from 10/sup -16/ cm, inside the nucleons, up to large-scale astrophysical bodies, including the early Universe at some nanosecond after the Big-Bang and temperatures of the order of 10/sup 2/ GeV. The picture is not yet completed, however, as we lack the observation of the Higgs boson, predicted in the 100-500 GeV range-a particle associated with the generation of particle masses and with the quantum fluctuations in the primordial Universe. In addition, the standard theory is expected to undergo a change of regime in the 10/sup 3/ GeV region, with the appearance of new families of particles, most likely associated with the onset of a new symmetry (supersymmetry). In 1994, the CERN Council approved the con...

  4. MALIGNANCY IN LARGE COLORECTAL LESIONS

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Oliveira dos SANTOS

    2014-09-01

    Full Text Available Context The size of colorectal lesions, besides a risk factor for malignancy, is a predictor for deeper invasion Objectives To evaluate the malignancy of colorectal lesions ≥20 mm. Methods Between 2007 and 2011, 76 neoplasms ≥20 mm in 70 patients were analyzed Results The mean age of the patients was 67.4 years, and 41 were women. Mean lesion size was 24.7 mm ± 6.2 mm (range: 20 to 50 mm. Half of the neoplasms were polypoid and the other half were non-polypoid. Forty-two (55.3% lesions were located in the left colon, and 34 in the right colon. There was a high prevalence of III L (39.5% and IV (53.9% pit patterns. There were 72 adenomas and 4 adenocarcinomas. Malignancy was observed in 5.3% of the lesions. Thirty-three lesions presented advanced histology (adenomas with high-grade dysplasia or early adenocarcinoma, with no difference in morphology and site. Only one lesion (1.3% invaded the submucosa. Lesions larger than 30 mm had advanced histology (P = 0.001. The primary treatment was endoscopic resection, and invasive carcinoma was referred to surgery. Recurrence rate was 10.6%. Conclusions Large colorectal neoplasms showed a low rate of malignancy. Endoscopic treatment is an effective therapy for these lesions.

  5. Large-area photonic crystals

    Science.gov (United States)

    Ruhl, Tilmann; Spahn, Peter; Hellmann, Gotz P.; Winkler, Holger

    2004-09-01

    Materials with a periodically modulated refractive index, with periods on the scale of light wavelengths, are currently attracting much attention because of their unique optical properties which are caused by Bragg scattering of the visible light. In nature, 3d structures of this kind are found in the form of opals in which monodisperse silica spheres with submicron diameters form a face-centered-cubic (fcc) lattice. Artificial opals, with the same colloidal-crystalline fcc structure, have meanwhile been prepared by crystallizing spherical colloidal particles via sedimentation or drying of dispersions. In this report, colloidal crystalline films are introduced that were produced by a novel technique based on shear flow in the melts of specially designed submicroscopic silica-polymer core-shell hybrid spheres: when the melt of these spheres flows between the plates of a press, the spheres crystallize along the plates, layer by layer, and the silica cores assume the hexagonal order corresponding to the (111) plane of the fcc lattice. This process is fast and yields large-area films, thin or thick. To enhance the refractive index contrast in these films, the colloidal crystalline structure was inverted by etching out the silica cores with hydrofluoric acid. This type of an inverse opal, in which the fcc lattice is formed by mesopores, is referred to as a polymer-air photonic crystal.

  6. Shutdown problems in large tokamaks

    International Nuclear Information System (INIS)

    Weldon, D.M.

    1978-01-01

    Some of the problems connected with a normal shutdown at the end of the burn phase (soft shutdown) and with a shutdown caused by disruptive instability (hard shutdown) have been considered. For a soft shutdown a cursory literature search was undertaken and methods for controlling the thermal wall loading were listed. Because shutdown computer codes are not widespread, some of the differences between start-up codes and shutdown codes were discussed along with program changes needed to change a start-up code to a shutdown code. For a hard shutdown, the major problems are large induced voltages in the ohmic-heating and equilibrium-field coils and high first wall erosion. A literature search of plasma-wall interactions was carried out. Phenomena that occur at the plasma-wall interface can be quite complicated. For example, material evaporated from the wall can form a virtual limiter or shield protecting the wall from major damage. Thermal gradients that occur during the interaction can produce currents whose associated magnetic field also helps shield the wall

  7. Large scale cross hole testing

    International Nuclear Information System (INIS)

    Ball, J.K.; Black, J.H.; Doe, T.

    1991-05-01

    As part of the Site Characterisation and Validation programme the results of the large scale cross hole testing have been used to document hydraulic connections across the SCV block, to test conceptual models of fracture zones and obtain hydrogeological properties of the major hydrogeological features. The SCV block is highly heterogeneous. This heterogeneity is not smoothed out even over scales of hundreds of meters. Results of the interpretation validate the hypothesis of the major fracture zones, A, B and H; not much evidence of minor fracture zones is found. The uncertainty in the flow path, through the fractured rock, causes sever problems in interpretation. Derived values of hydraulic conductivity were found to be in a narrow range of two to three orders of magnitude. Test design did not allow fracture zones to be tested individually. This could be improved by testing the high hydraulic conductivity regions specifically. The Piezomac and single hole equipment worked well. Few, if any, of the tests ran long enough to approach equilibrium. Many observation boreholes showed no response. This could either be because there is no hydraulic connection, or there is a connection but a response is not seen within the time scale of the pumping test. The fractional dimension analysis yielded credible results, and the sinusoidal testing procedure provided an effective means of identifying the dominant hydraulic connections. (10 refs.) (au)

  8. Mapping change in large networks.

    Directory of Open Access Journals (Sweden)

    Martin Rosvall

    2010-01-01

    Full Text Available Change is a fundamental ingredient of interaction patterns in biology, technology, the economy, and science itself: Interactions within and between organisms change; transportation patterns by air, land, and sea all change; the global financial flow changes; and the frontiers of scientific research change. Networks and clustering methods have become important tools to comprehend instances of these large-scale structures, but without methods to distinguish between real trends and noisy data, these approaches are not useful for studying how networks change. Only if we can assign significance to the partitioning of single networks can we distinguish meaningful structural changes from random fluctuations. Here we show that bootstrap resampling accompanied by significance clustering provides a solution to this problem. To connect changing structures with the changing function of networks, we highlight and summarize the significant structural changes with alluvial diagrams and realize de Solla Price's vision of mapping change in science: studying the citation pattern between about 7000 scientific journals over the past decade, we find that neuroscience has transformed from an interdisciplinary specialty to a mature and stand-alone discipline.

  9. Tipping device for large components

    International Nuclear Information System (INIS)

    Guigon, J.P.; Beraudier, D.

    1984-01-01

    For large components machining as components of a pressurized water reactor, it is necessary to have means allowing to present them in a position determined with regard to the machine tool used. The aim of the invention is a tipping device which consists of a base resting on the ground, a support-table mounted on this base, moving in rotation with the aid of at least a pivot joint of which axis is horizontal and parallel to the table and a gear pivot allowing to get a very good precision for the orientation of the piece and a very good stability whatever the orientation may be. The output shaft pinion of the base meshes with a gear wheel segment fixed to the table structure. Safety straps fasten the table structure to the base, as they are secured by horizontal pins. The toe pins run in straight slot holes incorporated in base jaws. The table rotation may be controlled by a spring-loaded braking mechanism which acts on the pivot axis and can be released by a hydraulic jack. The hydraulic pressure is used to prevent motor operation, unless the brakes have been released [fr

  10. Natural Selection in Large Populations

    Science.gov (United States)

    Desai, Michael

    2011-03-01

    I will discuss theoretical and experimental approaches to the evolutionary dynamics and population genetics of natural selection in large populations. In these populations, many mutations are often present simultaneously, and because recombination is limited, selection cannot act on them all independently. Rather, it can only affect whole combinations of mutations linked together on the same chromosome. Methods common in theoretical population genetics have been of limited utility in analyzing this coupling between the fates of different mutations. In the past few years it has become increasingly clear that this is a crucial gap in our understanding, as sequence data has begun to show that selection appears to act pervasively on many linked sites in a wide range of populations, including viruses, microbes, Drosophila, and humans. I will describe approaches that combine analytical tools drawn from statistical physics and dynamical systems with traditional methods in theoretical population genetics to address this problem, and describe how experiments in budding yeast can help us directly observe these evolutionary dynamics.

  11. Assembly considerations for large reflectors

    Science.gov (United States)

    Bush, H.

    1988-01-01

    The technologies developed at LaRC in the area of erectable instructures are discussed. The information is of direct value to the Large Deployable Reflector (LDR) because an option for the LDR backup structure is to assemble it in space. The efforts in this area, which include development of joints, underwater assembly simulation tests, flight assembly/disassembly tests, and fabrication of 5-meter trusses, led to the use of the LaRC concept as the baseline configuration for the Space Station Structure. The Space Station joint is linear in the load and displacement range of interest to Space Station; the ability to manually assemble and disassemble a 45-foot truss structure was demonstrated by astronauts in space as part of the ACCESS Shuttle Flight Experiment. The structure was built in 26 minutes 46 seconds, and involved a total of 500 manipulations of untethered hardware. Also, the correlation of the space experience with the neutral buoyancy simulation was very good. Sections of the proposed 5-meter bay Space Station truss have been built on the ground. Activities at LaRC have included the development of mobile remote manipulator systems (which can traverse the Space Station 5-meter structure), preliminary LDR sun shield concepts, LDR construction scenarios, and activities in robotic assembly of truss-type structures.

  12. Large superconducting coil fabrication development

    International Nuclear Information System (INIS)

    Brown, R.L.; Allred, E.L.; Anderson, W.C.; Burn, P.B.; Deaderick, R.I.; Henderson, G.M.; Marguerat, E.F.

    1975-01-01

    Toroidal fields for some fusion devices will be produced by an array of large superconducting coils. Their size, space limitation, and field requirements dictate that they be high performance coils. Once installed, accessibility for maintenance and repairs is severely restricted; therefore, good reliability is an obvious necessity. Sufficient coil fabrication will be undertaken to develop and test methods that are reliable, fast, and economical. Industrial participation will be encouraged from the outset to insure smooth transition from development phases to production phases. Initially, practice equipment for three meter bore circular coils will be developed. Oval shape coil forms will be included in the practice facility later. Equipment that is more automated will be developed with the expectation of winding faster and obtaining good coil quality. Alternate types of coil construction, methods of winding and insulating, will be investigated. Handling and assembly problems will be studied. All technology developed must be feasible for scaling up when much larger coils are needed. Experimental power reactors may need coils having six meter or larger bores

  13. Large earthquakes and creeping faults

    Science.gov (United States)

    Harris, Ruth A.

    2017-01-01

    Faults are ubiquitous throughout the Earth's crust. The majority are silent for decades to centuries, until they suddenly rupture and produce earthquakes. With a focus on shallow continental active-tectonic regions, this paper reviews a subset of faults that have a different behavior. These unusual faults slowly creep for long periods of time and produce many small earthquakes. The presence of fault creep and the related microseismicity helps illuminate faults that might not otherwise be located in fine detail, but there is also the question of how creeping faults contribute to seismic hazard. It appears that well-recorded creeping fault earthquakes of up to magnitude 6.6 that have occurred in shallow continental regions produce similar fault-surface rupture areas and similar peak ground shaking as their locked fault counterparts of the same earthquake magnitude. The behavior of much larger earthquakes on shallow creeping continental faults is less well known, because there is a dearth of comprehensive observations. Computational simulations provide an opportunity to fill the gaps in our understanding, particularly of the dynamic processes that occur during large earthquake rupture and arrest.

  14. Pressing technology for large bottoms

    International Nuclear Information System (INIS)

    Jilek, L.

    1986-01-01

    The technology has been selected of a circular plate bent into the shape of a trough, for pressing bottoms of pressure vessels from a circular plate of large diameter. The initial sheet is first bent in the middle by heating with the edges remaining straight. These are then welded longitudinally by electroslag welding and the circular shape is flame cut. The result will be a plate with a straight surface in the middle with raised edges which may be pressed into the desired shape. In this manner it is also possible to press pressure vessel bottoms with tube couplings from plates which are thickened in the middle and drilled; additional welding is then eliminated. Deformation from heat treatment may be avoided by the use of a fixture in the shape of a ring with a groove into which is fixed the edge of the bottom. During hardening of the bottom it will be necessary to care for the withdrawal of vapours and gases which would hamper uniform cooling. Bottom hardening with the grill and the cupola downwards has been proven. Deformation which occurs during treatment may to a certain extent be removed by calibration which cannot, however, be made without special fixtures and instruments. (J.B.)

  15. Relaxing a large cosmological constant

    International Nuclear Information System (INIS)

    Bauer, Florian; Sola, Joan; Stefancic, Hrvoje

    2009-01-01

    The cosmological constant (CC) problem is the biggest enigma of theoretical physics ever. In recent times, it has been rephrased as the dark energy (DE) problem in order to encompass a wider spectrum of possibilities. It is, in any case, a polyhedric puzzle with many faces, including the cosmic coincidence problem, i.e. why the density of matter ρ m is presently so close to the CC density ρ Λ . However, the oldest, toughest and most intriguing face of this polyhedron is the big CC problem, namely why the measured value of ρ Λ at present is so small as compared to any typical density scale existing in high energy physics, especially taking into account the many phase transitions that our Universe has undergone since the early times, including inflation. In this Letter, we propose to extend the field equations of General Relativity by including a class of invariant terms that automatically relax the value of the CC irrespective of the initial size of the vacuum energy in the early epochs. We show that, at late times, the Universe enters an eternal de Sitter stage mimicking a tiny positive cosmological constant. Thus, these models could be able to solve the big CC problem without fine-tuning and have also a bearing on the cosmic coincidence problem. Remarkably, they mimic the ΛCDM model to a large extent, but they still leave some characteristic imprints that should be testable in the next generation of experiments.

  16. The LUVOIR Large Mission Concept

    Science.gov (United States)

    O'Meara, John; LUVOIR Science and Technology Definition Team

    2018-01-01

    LUVOIR is one of four large mission concepts for which the NASA Astrophysics Division has commissioned studies by Science and Technology Definition Teams (STDTs) drawn from the astronomical community. We are currently developing two architectures: Architecture A with a 15.1 meter segmented primary mirror, and Architecture B with a 9.2 meter segmented primary mirror. Our focus in this presentation is the Architecture A LUVOIR. LUVOIR will operate at the Sun-Earth L2 point. It will be designed to support a broad range of astrophysics and exoplanet studies. The initial instruments developed for LUVOIR Architecture A include 1) a high-performance optical/NIR coronagraph with imaging and spectroscopic capability, 2) a UV imager and spectrograph with high spectral resolution and multi-object capability, 3) a high-definition wide-field optical/NIR camera, and 4) a high resolution UV/optical spectropolarimeter. LUVOIR will be designed for extreme stability to support unprecedented spatial resolution and coronagraphy. It is intended to be a long-lifetime facility that is both serviceable, upgradable, and primarily driven by guest observer science programs. In this presentation, we will describe the observatory, its instruments, and survey the transformative science LUVOIR can accomplish.

  17. Emergency preparedness for nuclear electric generating facilities in foreign countries: A brief survey of practices

    Energy Technology Data Exchange (ETDEWEB)

    Schuller, C R [Battelle Human Affairs Research Centers, Seattle, WA (United States); Marcus, A A; Hanhardt, Jr, A M; Selvin, M; Huelshoff, M [Pacific Northwest Laboratory, Richland, WA (United States)

    1980-12-01

    This report summarizes the emergency plans for accidents at nuclear power plants in Germany, Sweden, Switzerland, the United Kingdom, Canada, and France. Soviet Union documents were examined, but no published information was found on the subject. The study of foreign plans was to determine what U.S. planners might learn that could be useful to them. Plans of the foreign countries were published before the nuclear accident at Three Mile Island and reflected a generally accepted premise that a serious nuclear emergency would never occur. Therefore, there are few ideas of immediate use to U.S. planners. Most countries have since begun to re-examine their emergency planning. The study also discusses the emergency action levels, warning systems, evacuation management and procedures, and public information and education for people living near nuclear power plants and defines roles of nuclear facility operators and roles of the government. (author)

  18. Are uranium resources sufficient to face the expected revival of nuclear electricity production in the world?

    International Nuclear Information System (INIS)

    Seyve, C.

    2007-11-01

    This article proposes a table containing assessments of uranium resources in 2005 in different countries, and comments the evolution of uranium prices between 1968 and 2008. It discusses whether it would be possible to cope with a dramatic increase of uranium prices, whether it would be already possible to save uranium with the same level of electricity production, whether there is still some uranium resources to be discovered, whether we could rely on non conventional uranium sources (phosphates, sea water), and the role of future reactors

  19. Nuclear Energy Scientific, technical and social perspectives of nuclear-electrical conversion

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    2009-01-01

    The book begins with a brief review of basic knowledge historic milestones, radiation physics, biological effects of radiation and radioprotection, and nuclear physics. Then, several subjects in nuclear reactor engineering and nuclear power plants are introduced: a brief description of nuclear reactors and systems in a nuclear power plant, neutron physics, thermal hydraulics (including the thermodynamics of the whole nuclear power plant), nuclear fuels and fuel cycles, dynamic and control of nuclear reactors and nuclear power plant, safety of nuclear reactors, operation of power plants, decisions related with a nuclear power station (including sitting, economic and financial aspects, risks and detriments assessment), and a brief survey of future technologies. In the last chapter, the book enters into other subjects (in part of a philosophical nature) that relate, from the standpoint of energy, social and environmental problems with political issues and current world views

  20. Wish me luck as you wave me goodbye [UK nuclear electrical industry

    International Nuclear Information System (INIS)

    Holmes, Andrew.

    1989-01-01

    The British Department of Energy has finally decided that the privatisation of the country's nuclear capacity is feasible. The City will have nothing to do with it. This is not a surprise. What is a surprise is that the illusion that it could be sold has continued for so long. The Financial Times Energy Economist pointed out the difficulties of decommissioning some years ago. (author)

  1. Mission operations for unmanned nuclear electric propulsion outer planet exploration with a thermionic reactor spacecraft.

    Science.gov (United States)

    Spera, R. J.; Prickett, W. Z.; Garate, J. A.; Firth, W. L.

    1971-01-01

    Mission operations are presented for comet rendezvous and outer planet exploration NEP spacecraft employing in-core thermionic reactors for electric power generation. The selected reference missions are the Comet Halley rendezvous and a Jupiter orbiter at 5.9 planet radii, the orbit of the moon Io. The characteristics of the baseline multi-mission NEP spacecraft are presented and its performance in other outer planet missions, such as Saturn and Uranus orbiters and a Neptune flyby, are discussed. Candidate mission operations are defined from spacecraft assembly to mission completion. Pre-launch operations are identified. Shuttle launch and subsequent injection to earth escape by the Centaur D-1T are discussed, as well as power plant startup and the heliocentric mission phases. The sequence and type of operations are basically identical for all missions investigated.

  2. Nuclear electric dipole moment with relativistic effects in Xe and Hg atoms

    International Nuclear Information System (INIS)

    Oshima, Sachiko; Fujita, Takehisa; Asaga, Tomoko

    2007-01-01

    The atomic electric dipole moment (EDM) is evaluated by considering the relativistic effects as well as nuclear finite size effects in Xe and Hg atomic systems. Due to Schiff's theorem, the first order perturbation energy of EDM is canceled out by the second order perturbation energy for the point nucleus. The nuclear finite size effects arising from the intermediate atomic excitations may be finite for deformed nucleus but it is extremely small. The finite size contribution of the intermediate nuclear excitations in the second order perturbation energy is completely canceled by the third order perturbation energy. As the results, the finite contribution to the atomic EDM comes from the first order perturbation energy of relativistic effects, and it amounts to around 0.3 and 0.4 percents of the neutron EDM d n for Xe and Hg, respectively, though the calculations are carried out with a simplified single-particle nuclear model. From this relation in Hg atomic system, we can extract the neutron EDM which is found to be just comparable with the direct neutron EDM measurement

  3. The nuclear electric option in developing countries: Technical, economic, and political problems

    International Nuclear Information System (INIS)

    Andrade, F.A.

    1984-01-01

    During this century and the first half of the next, energy will be obtained principally from fossil fuels (coal, petroleum, and gas); in about 20 years, the production of petroleum will start to diminish due to the exhaustion of reserves, and the principal energy source will become coal, whose world reserves are ten times greater than hydrocarbons. In spite of its' petroleum reserves, Mexico should consider itself as a country poor in fossil fuel because its reserves of mineral coal are small. Petroleum and gas provide, at present more than 85% of the energy that the country uses and an amount similar to that which they consume is exported. Apart from burning it, petroleum has other very important applications such as petrochemicals and the production of fertilizers. At present, countries like Mexico which are poor in fossil fuels are sending fuels to countries rich in fossil fuels. They are doing this to achieve their development and to satisfy urgent needs. Faced with this situation which is irreversible, there is an obligation to programming the development of energy not in a six year period but 50 years or more, and to revise the program continually, due to the existing uncertainties; only in this way can the energy resources which will be left to new generations for their survival be planned

  4. Ultrahigh temperature vapor core reactor-MHD system for space nuclear electric power

    Science.gov (United States)

    Maya, Isaac; Anghaie, Samim; Diaz, Nils J.; Dugan, Edward T.

    1991-01-01

    The conceptual design of a nuclear space power system based on the ultrahigh temperature vapor core reactor with MHD energy conversion is presented. This UF4 fueled gas core cavity reactor operates at 4000 K maximum core temperature and 40 atm. Materials experiments, conducted with UF4 up to 2200 K, demonstrate acceptable compatibility with tungsten-molybdenum-, and carbon-based materials. The supporting nuclear, heat transfer, fluid flow and MHD analysis, and fissioning plasma physics experiments are also discussed.

  5. Nuclear electric energy in Romania - present status and long term prospects

    International Nuclear Information System (INIS)

    Fulga, V.

    1996-01-01

    The paper presents an analysis of the option for nuclear power in view of the decreasing energy demand in Romania, following industrial restructuring and abandonment of highly consuming industrial capacities. The costs of Cernavoda NPP based on CANDU type reactors amounted up to USD 2.2 billions, 160 % higher than the real price. Even though this reactor type is positioned among the highest as the safety is concerned, it could be assumed that even small incidents (predictable as well as repairable) would result in a decay of the tourism on Romanian sea shore or Danube delta. The paper raises also five questions and asks for updating the data necessary for a renewal of governmental decision concerning the Romanian nuclear power program

  6. The technical-economic problems concerning the search for sites for nuclear electricity generation facilities

    International Nuclear Information System (INIS)

    Zimmer, H.J.

    1976-01-01

    An outline of technical-physical fundamentals, of the design and the mode of operation of LWR reactors is followed by a brief description of the licensing procedure. It is pointed out that safety cannot be a criterion for a site because nuclear power plants have to be safe on every site. The problem of nuclear power plants in the vicinity of towns or densely populated areas is dealt with briefly, too. A method is proposed which allows to find a possible site while investing little time on search and evaluation and which stores this site in a site provision plan. The choice of possible sites is made on three levels which are independent of each other. Possible nuclear power plant sites, on the first level, are considered on the basis of the dominating influence of waste heat discharge and network integration. On the second level, macro-sites are determined by examining the realizability of these possible sites by looking at negative criteria, and, on the third level, the 'fine points' planning stage, a pool of potential micro-sites is determined by applying the 'measure of value' analysis. This is followed by citing an analytical method with which the order of priority amongst 8 possible sites in the USA was determined. (orig./HP) [de

  7. Nuclear Electricity in the United States : Providing Energy For The Nation's Security and Well-Being

    International Nuclear Information System (INIS)

    Finger, Harold B.

    1988-01-01

    Nuclear energy in the United States has made major contributions since the small Shippingport prototype power plant began operating in 1957. Recent legislative and regulatory actions, as well as research an development, are indicating that additional nuclear capacity can be available in the years ahead. These actions reflect the public's recognition of the importance of nuclear energy. In addition, recent regulatory actions are reaffirming the health and safety of our current nuclear plants, as well as of those being completed. The performance of our current plants is being improved through the conscious dedication of the entire industry to excellence. There is increasing discussion in the United States of the importance of advanced reactor concepts development. The next generation of nuclear plants is already being ordered outside of the United States for example, here in Korea, in Japan, in the United Kingdom and those plants all use light water reactors. We are pleased that U. S. companies are working with you on these new plants. That continues to mean that we never let up on our drive for excellence. Excellence in operations must continue to be the conscious target of all operators. Excellence in communications to the public of the need for electrical capacity, of the benefits of nuclear energy, and of the excellence being achieved in operations is also essential. And excellence in communication to decision makers at all levels of government is also required to assure that sound legalisation and regulation is established and implemented

  8. Nuclear electric capacity expansion in Mexico: system effects of reactor size and cost

    International Nuclear Information System (INIS)

    Thayer, G.R.; Abbey, D.S.; Hardie, R.W.; Enriquez, R.P.; Uria, E.G.

    1984-01-01

    Mexico's electrical generation capacity could more than double over the next ten years - from about 15 GWe currently to as much as 35 GWe in 1990. While new capacity additions will be predominantly oil-fired in the 1980's, nuclear power will become increasingly important in the 1990's. This study investigated the appropriate size of new, nuclear capacity additions by assessing the implications of installing different size reactors into Mexico's electrical grid. Included in the assessments of reactor sizes are estimates of electrical generation costs and comparisons of the effective load-carrying capability of a 10 GWe nuclear capacity expansion

  9. The cost of nuclear electricity in France over the last ten years

    International Nuclear Information System (INIS)

    Moynet, G.

    1984-01-01

    The author analyzes developments for the main components in production costs of the nuclear kWh over the past ten years: investment, operation, fuel. Progression is 93% expressed in constant currency unit. But to assess this prima facie impressive figure correctly, it should be realised that the cost of the coal kWh has risen by more than 100% over the same period. The author comments on the main factors in this development [fr

  10. Radioactive waste assessment using 'moderate growth in nuclear electricity generation' scenario

    International Nuclear Information System (INIS)

    Richardson, J.A.; Goodill, D.R.; Tymons, B.J.

    1985-05-01

    This report describes an assessment of radioactive waste management arisings from a defined nuclear power generation scenario -Scheme 3. Scheme 3 assumes a moderate growth in nuclear generation scenario with raw waste arisings from 3 main groups: (i) existing and committed commercial reactors; (ii) fuel reprocessing plants; (iii) research, industry and medicine. No decommissioning wastes are considered except for arisings from the final fuel cores from decommissioned reactors. The study uses the SIMULATION2 code which models waste material flows through the system. With a knowledge of the accumulations and average production rates of the raw wastes and their isotopic compositions (or total activities), the rates at which conditioned wastes become available for transportation and disposal are calculated, with specific activity levels. The data bases for the inventory calculations and the assumptions concerning future operation of nuclear facilities were those current in 1983. Both the inventory data and plans for the future of existing nuclear installations have been updated since these calculations were completed. Therefore the results from this assessment do not represent the most up-to-date information available. The report does, however, illustrate the methodology of assessment, and indicates the type of information that can be generated. (author)

  11. Constraining climate change with nuclear electricity and hydrogen (N + H2)

    International Nuclear Information System (INIS)

    Miller, A.I.; Duffey, R.B.

    2003-08-01

    Electricity produced from non-carbon-based sources is the only available technology to curb the rise of CO 2 levels in the Earth's atmosphere. While it is comparatively easy to replace carbon-fuelled electricity production with nuclear and other non-carbon sources, electricity will also have to penetrate deeply into transportation to achieve sufficient leverage to displace existing carbon-based energy use. The use of hydrogen, produced by water electrolysis, resolves the intractability of on-board storage of electricity, and provides a distributed source. This paper first reviews the scenarios for future energy use and supply created by the Intergovernmental Panel on Climate Change (IPCC), which are also representative of the main IAEA/NEA scenarios. It then discusses ways in which non-carbon-based energy can be applied to the transportation sector in the form of hydrogen. Finally, the potential effects of this application have been calculated for the key IPCC marker scenarios using the MAGICC-SCENGEN software package. A mechanism inherent in the model can provide quite accurate prediction of the effect of CO 2 concentration on global temperatures 20 years later. This provides a useful and new way to estimate the effects of delayed action to reduce CO 2 emissions. The IPCC's scenarios already include considerable expansion of energy from nuclear and other sustainable energy sources (e.g. wind, solar, biomass), but the extent is generally too small to substantially restrain the build-up of greenhouse gases in the Earth's atmosphere and to diminish the consequent projected rate of rise of average global temperatures. Much greater substitution is needed, and this paper argues that only nuclear power can provide the preponderant source of energy for a sufficient and sustainable switch away from carbon. Though the storage of spent-fuel wastes is now developed technology, waste disposal is often cited as a constraint on nuclear power. It is a strange objection given that the technology to handle the damaging wastes from carbon-based energy is almost non-existent. The best estimates of increases of a few degrees in global average temperature sound innocuous; they can be further muffled by invoking uncertainties over the details of the modeling. The consequent complacency is all too evident in Society's hesitant response. Yet, we believe complacency is dangerously inappropriate given the potential for exceedingly dangerous, long-lived and likely irreversible effects on our planetary habitat. (author)

  12. Constraining climate change with nuclear electricity and hydrogen (N + H{sub 2})

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.I.; Duffey, R.B

    2003-08-01

    Electricity produced from non-carbon-based sources is the only available technology to curb the rise of CO{sub 2} levels in the Earth's atmosphere. While it is comparatively easy to replace carbon-fuelled electricity production with nuclear and other non-carbon sources, electricity will also have to penetrate deeply into transportation to achieve sufficient leverage to displace existing carbon-based energy use. The use of hydrogen, produced by water electrolysis, resolves the intractability of on-board storage of electricity, and provides a distributed source. This paper first reviews the scenarios for future energy use and supply created by the Intergovernmental Panel on Climate Change (IPCC), which are also representative of the main IAEA/NEA scenarios. It then discusses ways in which non-carbon-based energy can be applied to the transportation sector in the form of hydrogen. Finally, the potential effects of this application have been calculated for the key IPCC marker scenarios using the MAGICC-SCENGEN software package. A mechanism inherent in the model can provide quite accurate prediction of the effect of CO{sub 2} concentration on global temperatures 20 years later. This provides a useful and new way to estimate the effects of delayed action to reduce CO{sub 2} emissions. The IPCC's scenarios already include considerable expansion of energy from nuclear and other sustainable energy sources (e.g. wind, solar, biomass), but the extent is generally too small to substantially restrain the build-up of greenhouse gases in the Earth's atmosphere and to diminish the consequent projected rate of rise of average global temperatures. Much greater substitution is needed, and this paper argues that only nuclear power can provide the preponderant source of energy for a sufficient and sustainable switch away from carbon. Though the storage of spent-fuel wastes is now developed technology, waste disposal is often cited as a constraint on nuclear power. It is a strange objection given that the technology to handle the damaging wastes from carbon-based energy is almost non-existent. The best estimates of increases of a few degrees in global average temperature sound innocuous; they can be further muffled by invoking uncertainties over the details of the modeling. The consequent complacency is all too evident in Society's hesitant response. Yet, we believe complacency is dangerously inappropriate given the potential for exceedingly dangerous, long-lived and likely irreversible effects on our planetary habitat. (author)

  13. The PEGASUS Drive: A nuclear electric propulsion system for the space exploration initiative

    International Nuclear Information System (INIS)

    Coomes, E.P.; Dagle, J.E.

    1991-01-01

    The advantages of using electric propulsion for propulsion are well-known in the aerospace community. The high specific impulse, lower propellant requirements, and lower system mass make it a very attractive propulsion option for the Space Exploration Initiative (SEI), especially for the transport of cargo. One such propulsion system is the PEGASUS Drive (Coomes et al. 1987). In its original configuration, the PEGASUS Drive consisted of a 10-MWe power source coupled to a 6-MW magnetoplasmadynamic (MPD) thruster system. The PEGASUS Drive propelled a manned vechicle to Mars and back in 601 days. By removing the crew and their associated support systems from the space craft and by incorporating technology advances in reactor design and heat rejection systems, a second generation PEGASUS Drive can be developed with an alpha less than two. Utilizing this propulsion system, a 400-MT cargo vechicle, assembled and loaded in low Earth orbit (LEO), could deliver 262 MT of supplies and hardware to MARS 282 days after escaping Earth orbit. Upon arrival at Mars the transport vehicle would place its cargo in the desired parking orbit around Mars and then proceed to synchronous orbit above the desired landing sight. Using a laser transmitter, PEGASUS could provide 2-MW on the surface to operate automated systems deployed earlier and then provide surface power to support crew activities after their arrival. The additional supplies and hardware, coupled with the availability of megawatt levels of electric power on the Mars surface, would greatly enhance and even expand the mission options being considered under SEI

  14. The method research of the simulator training and examination of the nuclear electricity staff

    International Nuclear Information System (INIS)

    Huang Fangzhi; Zhang Yuanfang

    1994-01-01

    The simulator training and examination of nuclear power plant operator are of an important guarantee for the nuclear power plant operation safety. The authors introduce various training courses which have been held in the Nuclear Power Plant Simulation Training Center of Tsinghua University since 1988, and analyze the different requirements and features for different classes such as operator candidate training course, operator retraining course and nuclear and electricity staff course. The lesson arrangement, examination method and mark standard are presented, which is carried out in the Nuclear Power Plant Simulation Training Center of Tsinghua University

  15. Review of nuclear electricity generation and desalination plants and evaluation of SMART application

    International Nuclear Information System (INIS)

    Kang, Han Ok; Kang, Hyung Suk; Cho, Bong Hyun; Yoon, Ju Hyeon; Kim, Hwan Yeol; Lee, Young Jin; Kim, Joo Pyung; Lee, Doo Jeong; Chang, Moon Hee

    1998-03-01

    KAERI are developing a new advanced integral reactor named SMART for dual application purpose of the electric power generation and seawater desalination. This report are describing the general desalting methods with its technology development and the coupling schemes between electricity generation system and desalting system. Though MSF takes the most part of currently operating seawater desalination plants, MED and RO has been preferred in the past decade. MED has a advantage over MSF with the view to investment costs and energy efficiency. The coupling between electricity generation system and desalination system can be realized by using one of back pressure cycle, extraction cycle, and multi-shaft cycle. New design and operating strategy has to be established for various environment and load conditions. To evaluate the candidate desalination systems of SMART and the coupling method of it with other secondary systems, the desalted water and electricity were calculated through the several options. The result shows that back pressure cycle is preferred at the high water/power ratio and extraction cycle at the low value. If energy efficiency are only considered, RO will be best choice. (author). 17 refs., 12 tabs., 31 figs

  16. Study and development of equipment supervision technique system and its management software for nuclear electricity production

    International Nuclear Information System (INIS)

    Zhang Liying; Zou Pingguo; Zhu Chenghu; Lu Haoliang; Wu Jie

    2008-01-01

    The equipment supervision technique system, which standardized the behavior of supervision organizations in planning and implementing of equipment supervision, is built up based on equipment supervision technique documents, such as Quality Supervision Classifications, Special Supervision Plans and Supervision Guides. Furthermore, based on the research, the equipment supervision management information system is developed by Object Oriented Programming, which consists of supervision information, supervision technique, supervision implementation, quality statistics and analysis module. (authors)

  17. Comparison of Direct and Indirect Gas Reactor Brayton Systems for Nuclear Electric Space Propulsion

    International Nuclear Information System (INIS)

    M Postlehwait; P DiLorenzo; S Belanger; J Ashcroft

    2005-01-01

    Gas reactor systems are being considered as candidates for use in generating power for the Prometheus-1 spacecraft, along with other NASA missions as part of the Prometheus program. Gas reactors offer a benign coolant, which increases core and structural materials options. However, the gas coolant has inferior thermal transport properties, relative to other coolant candidates such as liquid metals. This leads to concerns for providing effective heat transfer and for minimizing pressure drop within the reactor core. In direct gas Brayton systems, i.e. those with one or more Brayton turbines in the reactor cooling loop, the ability to provide effective core cooling and low pressure drop is further constrained by the need for a low pressure, high molecular weight gas, typically a mixture of helium and xenon. Use of separate primary and secondary gas loops, one for the reactor and one or more for the Brayton system(s) separated by heat exchanger(s), allows for independent optimization of the pressure and gas composition of each loop. The reactor loop can use higher pressure pure helium, which provides improved heat transfer and heat transport properties, while the Brayton loop can utilize lower pressure He-Xe. However, this approach requires a separate primary gas circulator and also requires gas to gas heat exchangers. This paper focuses on the trade-offs between the direct gas reactor Brayton system and the indirect gas Brayton system. It discusses heat exchanger arrangement and materials options and projects heat exchanger mass based on heat transfer area and structural design needs. Analysis indicates that these heat exchangers add considerable mass, but result in reactor cooling and system resiliency improvements

  18. Constraining climate change with nuclear electricity and hydrogen (N + H{sub 2})

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A I; Duffey, R B

    2003-08-01

    Electricity produced from non-carbon-based sources is the only available technology to curb the rise of CO{sub 2} levels in the Earth's atmosphere. While it is comparatively easy to replace carbon-fuelled electricity production with nuclear and other non-carbon sources, electricity will also have to penetrate deeply into transportation to achieve sufficient leverage to displace existing carbon-based energy use. The use of hydrogen, produced by water electrolysis, resolves the intractability of on-board storage of electricity, and provides a distributed source. This paper first reviews the scenarios for future energy use and supply created by the Intergovernmental Panel on Climate Change (IPCC), which are also representative of the main IAEA/NEA scenarios. It then discusses ways in which non-carbon-based energy can be applied to the transportation sector in the form of hydrogen. Finally, the potential effects of this application have been calculated for the key IPCC marker scenarios using the MAGICC-SCENGEN software package. A mechanism inherent in the model can provide quite accurate prediction of the effect of CO{sub 2} concentration on global temperatures 20 years later. This provides a useful and new way to estimate the effects of delayed action to reduce CO{sub 2} emissions. The IPCC's scenarios already include considerable expansion of energy from nuclear and other sustainable energy sources (e.g. wind, solar, biomass), but the extent is generally too small to substantially restrain the build-up of greenhouse gases in the Earth's atmosphere and to diminish the consequent projected rate of rise of average global temperatures. Much greater substitution is needed, and this paper argues that only nuclear power can provide the preponderant source of energy for a sufficient and sustainable switch away from carbon. Though the storage of spent-fuel wastes is now developed technology, waste disposal is often cited as a constraint on nuclear power. It is a strange objection given that the technology to handle the damaging wastes from carbon-based energy is almost non-existent. The best estimates of increases of a few degrees in global average temperature sound innocuous; they can be further muffled by invoking uncertainties over the details of the modeling. The consequent complacency is all too evident in Society's hesitant response. Yet, we believe complacency is dangerously inappropriate given the potential for exceedingly dangerous, long-lived and likely irreversible effects on our planetary habitat. (author)

  19. US central station nuclear electric generating units: significant milestones (status as of January 1, 1979)

    International Nuclear Information System (INIS)

    1979-03-01

    Construction and operational milestones are tabulated for US nuclear power plants. Data are presented on nuclear steam supply system orders. A schedule of commercial operation and projected capital costs through 1990 is given

  20. Recent developments of the MOA thruster concerning its application for nuclear electric and thermal propulsion

    International Nuclear Information System (INIS)

    Frischauf, N.; Hettmer, M.; Grassauer, A.; Bartusch, T.; Koudelka, O.

    2007-01-01

    The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA for Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of 2 coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. Several prototypes have been built and tested, the results that were obtained are promising: with an overall power consumption of 400 W, 6 to 11 mN of thrust could be obtained, leading on the average to a specific power of about 50 W/mN. Better results are expected for optimised prototypes in terms of power consumption

  1. US central station nuclear electric generating units: significant milestones (status as of July 1, 1980)

    International Nuclear Information System (INIS)

    1980-09-01

    The status of 189 US nuclear power plants is reported in a table which gives the name, owner, capacity, type, NSSS architect and contractor and data of public announcement, NSSS order, licensing, and initial operation. The plants are also indexed according to state, region, utility, and alphabetical name. The utility nuclear steam supply system orders are also listed

  2. Economic aspects of peaceful use of nuclear technology in Iran with emphasis on nuclear electricity

    International Nuclear Information System (INIS)

    Zara, Abdolreza

    1995-09-01

    Since fossil fuel resources are limited from the point of view of supply in Iran and on the other hand the pressure due to population growth, have all increased demand for energy in the industry, service and domestic sections. Since the capacity of hydroelectric energy is limited and these capacities will be soon completely used, and using other energy resources as solar energy, wind power, biomass and tidal energy are not economically efficient on national scale, the only choice to gain cheap and clean energy source is to develop multipurpose nuclear power plants for generation of electric power. Since the technical studies have been done on nuclear energy and the subject of peaceful uses of nuclear technology is virgin in this country, therefore, we intended to introduce the usefulness of nuclear technique; and its role in economic development. In this respect, since electric energy is one of the factors that runs the industrial wheel, therefore, the emphasis is placed on the economic generation of electric power through nuclear energy

  3. The development of on-line thermal performance monitors in Nuclear Electric Company's stations

    International Nuclear Information System (INIS)

    Conner, A.S.

    1992-01-01

    The paper examines the economic benefits of using on-line monitoring techniques in assisting Station Staff with the task of optimising the efficient use of reactor fuel. The role of thermal performance monitoring for detecting changes in plant condition is also examined and the way in which the data can be used by engineers to assist with the preparation of operating and maintenance programmes. To enable genuine gradual changes in plant performance to be detected when operating against a background of changing plant signal accuracy conditions, plant transducers have to be calibrated on a regular basis. This can be both costly and labour intensive. To reduce this requirement for regular calibrations, an automatic software signal verification program has been developed for use in on-line monitoring schemes. It forms part of the total unit performance calculation package and uses a whole plant model to verify plant signals. All plant signals used to calculate unit heat rate are verified typically every 15 minutes with signals going outside predetermined limits being automatically reported to the user. The program is interactive allowing the user to interrogate the condition of the signal, with respect to both its error magnitude and rate of drift outside signal limits. The program runs in real time mode on a Workstation connected directly to the plant

  4. Concept of a large-capacity irradiated-fuel-reprocessing plant

    International Nuclear Information System (INIS)

    Buck, C.; Couture, J.; Issel, W.; Mamelle, J.

    The processing of LWR fuels in recent years has run into difficulties due to the adaptation of the Purex process to these fuels with a high irradiation rate. This has led to development of new technological techniques. High-capacity plants should, in the future, limit their discharge of liquid and gaseous effluents to values comparable to those of nuclear electric stations. Investment costs necessary for processing the effluents and for temporary storage of the wastes are part of the total cost of these plants. However, the investments remain within acceptable limits. The 1500-ton/year plant presented is an example of what can be done in the 1980's

  5. Large-scale galaxy bias

    Science.gov (United States)

    Desjacques, Vincent; Jeong, Donghui; Schmidt, Fabian

    2018-02-01

    This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy statistics. We then review the excursion-set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  6. Large-scale galaxy bias

    Science.gov (United States)

    Jeong, Donghui; Desjacques, Vincent; Schmidt, Fabian

    2018-01-01

    Here, we briefly introduce the key results of the recent review (arXiv:1611.09787), whose abstract is as following. This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a detailed derivation of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which include the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in its general form, which elucidates the physical meaning of the bias parameters, and a detailed description of the connection between bias parameters and galaxy (or halo) statistics. We then review the excursion set formalism and peak theory which provide predictions for the values of the bias parameters. In the remainder of the review, we consider the generalizations of galaxy bias required in the presence of various types of cosmological physics that go beyond pressureless matter with adiabatic, Gaussian initial conditions: primordial non-Gaussianity, massive neutrinos, baryon-CDM isocurvature perturbations, dark energy, and modified gravity. Finally, we discuss how the description of galaxy bias in the galaxies' rest frame is related to clustering statistics measured from the observed angular positions and redshifts in actual galaxy catalogs.

  7. One to Large N Gradiometry

    Science.gov (United States)

    Langston, C. A.

    2017-12-01

    The seismic wave gradient tensor can be derived from a variety of field observations including measurements of the wavefield by a dense seismic array, strain meters, and rotation meters. Coupled with models of wave propagation, wave gradients along with the original wavefield can give estimates of wave attributes that can be used to infer wave propagation directions, apparent velocities, spatial amplitude behavior, and wave type. Compact geodetic arrays with apertures of 0.1 wavelength or less can be deployed to provide wavefield information at a localized spot similar to larger phased arrays with apertures of many wavelengths. Large N, spatially distributed arrays can provide detailed information over an area to detect structure changes. Key to accurate computation of spatial gradients from arrays of seismic instruments is knowledge of relative instrument responses, particularly component sensitivities and gains, along with relative sensor orientations. Array calibration has been successfully performed for the 14-element Pinyon Flat, California, broadband array using long-period teleseisms to achieve relative precisions as small as 0.2% in amplitude and 0.35o in orientation. Calibration has allowed successful comparison of horizontal seismic strains from local and regional seismic events with the Plate Boundary Observatory (PBO) borehole strainmeter located at the facility. Strains from the borehole strainmeter in conjunction with ground velocity from a co-located seismometer are used as a "point" array in estimating wave attributes for the P-SV components of the wavefield. An effort is underway to verify the calibration of PBO strainmeters in southern California and their co-located borehole seismic sensors to create an array of point arrays for use in studies of regional wave propagation and seismic sources.

  8. Large capacity temporary visual memory

    Science.gov (United States)

    Endress, Ansgar D.; Potter, Mary C.

    2014-01-01

    Visual working memory (WM) capacity is thought to be limited to three or four items. However, many cognitive activities seem to require larger temporary memory stores. Here, we provide evidence for a temporary memory store with much larger capacity than past WM capacity estimates. Further, based on previous WM research, we show that a single factor — proactive interference — is sufficient to bring capacity estimates down to the range of previous WM capacity estimates. Participants saw a rapid serial visual presentation (RSVP) of 5 to 21 pictures of familiar objects or words presented at rates of 4/s or 8/s, respectively, and thus too fast for strategies such as rehearsal. Recognition memory was tested with a single probe item. When new items were used on all trials, no fixed memory capacities were observed, with estimates of up to 9.1 retained pictures for 21-item lists, and up to 30.0 retained pictures for 100-item lists, and no clear upper bound to how many items could be retained. Further, memory items were not stored in a temporally stable form of memory, but decayed almost completely after a few minutes. In contrast, when, as in most WM experiments, a small set of items was reused across all trials, thus creating proactive interference among items, capacity remained in the range reported in previous WM experiments. These results show that humans have a large-capacity temporary memory store in the absence of proactive interference, and raise the question of whether temporary memory in everyday cognitive processing is severely limited as in WM experiments, or has the much larger capacity found in the present experiments. PMID:23937181

  9. Seismic analysis of large pools

    Energy Technology Data Exchange (ETDEWEB)

    Dong, R.G.; Tokarz, F.J.

    1976-11-17

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

  10. Seismic analysis of large pools

    International Nuclear Information System (INIS)

    Dong, R.G.; Tokarz, F.J.

    1976-01-01

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

  11. Large optics inspection, tilting, and washing stand

    Science.gov (United States)

    Ayers, Marion Jay [Brentwood, CA; Ayers, Shannon Lee [Brentwood, CA

    2010-08-24

    A large optics stand provides a risk free means of safely tilting large optics with ease and a method of safely tilting large optics with ease. The optics are supported in the horizontal position by pads. In the vertical plane the optics are supported by saddles that evenly distribute the optics weight over a large area.

  12. Large dams and risk management

    International Nuclear Information System (INIS)

    Cazelais, N.

    2003-01-01

    In July 1996, Quebec's Saguenay region was subjected to intensive rainfall which caused severe floods and uncontrolled release of several reservoirs, resulting in extensive damage to dam structures and reservoirs. The probability of occurrence for that disaster was 1:10,000. Following the disaster, the Quebec government established a dam management body entitled the Commission scientifique et technique sur la gestion des barrages, which pointed out several safety shortcomings of existing dams. Many were either very old or had undergone significant function change without being subsequently re-evaluated. A report by the Commission stated that damage following the floods could have been limited if the design and operating standards of the dams had been more stringent. A Dam Safety Act was adopted by the Quebec National Assembly on May 30, 2000 following recommendations to retain safer structures. The Act demands regular reporting of operating procedures. Seismic activity was noted as being a topic that requires in-depth examination since Quebec's St. Lawrence Valley, particularly the Charlevoix region, is one of Canada's largest seismic zones. The other is on the west coast in British Columbia. Earthquakes in Quebec are less intense than the ones in British Columbia, but they have higher frequency content which exerts a quasi-resonance wave effect which impacts roads, bridges, buildings and hydroelectric generating facilities. Hydro-Quebec is a public utility which owns 563 retaining structures, of which 228 are ranked as large dams that measure more than 15 metres high, 400 metres long and with a reservoir capacity of more than 1 million cubic metres of water. Hydro-Quebec addresses hydrological, seismic, technological and human risks through a dam safety procedure that includes structured plans for choosing best alternatives through staged exercises. Hazard levels are minimized through the adoption of emergency, prevention and alleviation measures. The utility

  13. Large truck and bus crash facts, 2010.

    Science.gov (United States)

    2012-09-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2010. Selected crash statistics on passenger : vehicles are also presen...

  14. Large truck and bus crash facts, 2012.

    Science.gov (United States)

    2014-06-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2012. Selected crash statistics on passenger vehicles are also presented ...

  15. Large truck and bus crash facts, 2013.

    Science.gov (United States)

    2015-04-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and property damage only crashes involving large trucks and buses in 2013. Selected crash statistics on passenger vehicles are also presented ...

  16. Large truck and bus crash facts, 2009.

    Science.gov (United States)

    2011-10-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2009. Selected crash statistics on passenger : vehicles are also presen...

  17. Large truck and bus crash facts, 2011.

    Science.gov (United States)

    2013-10-01

    This annual edition of Large Truck and Bus Crash Facts contains descriptive statistics about fatal, injury, and : property damage only crashes involving large trucks and buses in 2011. Selected crash statistics on passenger : vehicles are also presen...

  18. Superconducting materials for large scale applications

    International Nuclear Information System (INIS)

    Dew-Hughes, D.

    1975-01-01

    Applications of superconductors capable of carrying large current densities in large-scale electrical devices are examined. Discussions are included on critical current density, superconducting materials available, and future prospects for improved superconducting materials. (JRD)

  19. Investing in a Large Stretch Press

    Science.gov (United States)

    Choate, M.; Nealson, W.; Jay, G.; Buss, W.

    1986-01-01

    Press for forming large aluminum parts from plates provides substantial economies. Study assessed advantages and disadvantages of investing in large stretch-forming press, and also developed procurement specification for press.

  20. Large-scale energy consumers pay less

    International Nuclear Information System (INIS)

    Denneman, A.

    2012-01-01

    The price of electricity in the Netherlands rose with 6 percent in the first quarter of 2012, whereas large business consumers are paying less. The natural gas price has risen with about 10 percent in the last year, both for households and for large business consumers. Meanwhile, households are paying twice as much for electricity and gas as large business consumers. [nl

  1. 27 CFR 19.915 - Large plants.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Large plants. 19.915... OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Distilled Spirits For Fuel Use Permits § 19.915 Large plants. Any person wishing to establish a large plant shall make application for and obtain an...

  2. 75 FR 73983 - Assessments, Large Bank Pricing

    Science.gov (United States)

    2010-11-30

    ... 327 RIN 3064-AD66 Assessments, Large Bank Pricing AGENCY: Federal Deposit Insurance Corporation (FDIC... Pricing. This correction clarifies that the comment period for the Assessments, Large Bank Pricing ends January 3, 2011. FOR FURTHER INFORMATION CONTACT: Lisa Ryu, Chief, Large Bank Pricing Section, Division of...

  3. 76 FR 10671 - Assessments, Large Bank Pricing

    Science.gov (United States)

    2011-02-25

    ... 327 Assessments, Large Bank Pricing; Final Rule #0;#0;Federal Register / Vol. 76 , No. 38 / Friday... Part 327 RIN 3064-AD66 Assessments, Large Bank Pricing AGENCY: Federal Deposit Insurance Corporation..., (202) 898-6796; Lisa Ryu, Chief, Large Bank Pricing Section, Division of Insurance and Research, (202...

  4. Why did humans develop a large brain?

    OpenAIRE

    Muscat Baron, Yves

    2012-01-01

    "Of all animals, man has the largest brain in proportion to his size"- Aristotle. Dr Yves Muscat Baron shares his theory on how humans evolved large brains. The theory outlines how gravity could have helped humans develop a large brain- the author has named the theory 'The Gravitational Vascular Theory'. http://www.um.edu.mt/think/why-did-humans-develop-a-large-brain/

  5. Large N baryons, strong coupling theory, quarks

    International Nuclear Information System (INIS)

    Sakita, B.

    1984-01-01

    It is shown that in QCD the large N limit is the same as the static strong coupling limit. By using the static strong coupling techniques some of the results of large N baryons are derived. The results are consistent with the large N SU(6) static quark model. (author)

  6. Forecasting distribution of numbers of large fires

    Science.gov (United States)

    Haiganoush K. Preisler; Jeff Eidenshink; Stephen Howard; Robert E. Burgan

    2015-01-01

    Systems to estimate forest fire potential commonly utilize one or more indexes that relate to expected fire behavior; however they indicate neither the chance that a large fire will occur, nor the expected number of large fires. That is, they do not quantify the probabilistic nature of fire danger. In this work we use large fire occurrence information from the...

  7. Large-group psychodynamics and massive violence

    Directory of Open Access Journals (Sweden)

    Vamik D. Volkan

    2006-06-01

    Full Text Available Beginning with Freud, psychoanalytic theories concerning large groups have mainly focused on individuals' perceptions of what their large groups psychologically mean to them. This chapter examines some aspects of large-group psychology in its own right and studies psychodynamics of ethnic, national, religious or ideological groups, the membership of which originates in childhood. I will compare the mourning process in individuals with the mourning process in large groups to illustrate why we need to study large-group psychology as a subject in itself. As part of this discussion I will also describe signs and symptoms of large-group regression. When there is a threat against a large-group's identity, massive violence may be initiated and this violence in turn, has an obvious impact on public health.

  8. Ethics of large-scale change

    OpenAIRE

    Arler, Finn

    2006-01-01

      The subject of this paper is long-term large-scale changes in human society. Some very significant examples of large-scale change are presented: human population growth, human appropriation of land and primary production, the human use of fossil fuels, and climate change. The question is posed, which kind of attitude is appropriate when dealing with large-scale changes like these from an ethical point of view. Three kinds of approaches are discussed: Aldo Leopold's mountain thinking, th...

  9. Large Display Interaction Using Mobile Devices

    OpenAIRE

    Bauer, Jens

    2015-01-01

    Large displays become more and more popular, due to dropping prices. Their size and high resolution leverages collaboration and they are capable of dis- playing even large datasets in one view. This becomes even more interesting as the number of big data applications increases. The increased screen size and other properties of large displays pose new challenges to the Human- Computer-Interaction with these screens. This includes issues such as limited scalability to the number of users, diver...

  10. Large transverse momentum behavior of gauge theories

    International Nuclear Information System (INIS)

    Coquereaux, Robert; De Rafael, Eduardo.

    1977-05-01

    The large transverse momentum behavior of Compton scattering and Moeller scattering in Quantum Electrodynamics; and of elastic quark-quark scattering in Quantum Chromodynamics are examined in perturbation theory. The results strongly suggest that the large transverse momentum regime in gauge theories is governed by a differential equation of the Callan-Symanzik type with a suitable momentum dependent anomalous dimension term. An explicit solution for the quark-quark elastic scattering amplitude at large transverse momentum is given

  11. Large-scale grid management; Storskala Nettforvaltning

    Energy Technology Data Exchange (ETDEWEB)

    Langdal, Bjoern Inge; Eggen, Arnt Ove

    2003-07-01

    The network companies in the Norwegian electricity industry now have to establish a large-scale network management, a concept essentially characterized by (1) broader focus (Broad Band, Multi Utility,...) and (2) bigger units with large networks and more customers. Research done by SINTEF Energy Research shows so far that the approaches within large-scale network management may be structured according to three main challenges: centralization, decentralization and out sourcing. The article is part of a planned series.

  12. Reliability of large and complex systems

    CERN Document Server

    Kolowrocki, Krzysztof

    2014-01-01

    Reliability of Large and Complex Systems, previously titled Reliability of Large Systems, is an innovative guide to the current state and reliability of large and complex systems. In addition to revised and updated content on the complexity and safety of large and complex mechanisms, this new edition looks at the reliability of nanosystems, a key research topic in nanotechnology science. The author discusses the importance of safety investigation of critical infrastructures that have aged or have been exposed to varying operational conditions. This reference provides an asympt

  13. Implementing Large Projects in Software Engineering Courses

    Science.gov (United States)

    Coppit, David

    2006-01-01

    In software engineering education, large projects are widely recognized as a useful way of exposing students to the real-world difficulties of team software development. But large projects are difficult to put into practice. First, educators rarely have additional time to manage software projects. Second, classrooms have inherent limitations that…

  14. Asian Eden : large herbivore ecology in India

    NARCIS (Netherlands)

    Ahrestani, F.S.

    2009-01-01

    The study of large mammalian herbivore ecology has a strong allometric tradition. The
    majority of studies that have helped better understand how body mass affects large herbivore
    ecology in the tropics, from a biological, functional, and ecological perspective, are from
    Africa.

  15. The large deviation approach to statistical mechanics

    International Nuclear Information System (INIS)

    Touchette, Hugo

    2009-01-01

    The theory of large deviations is concerned with the exponential decay of probabilities of large fluctuations in random systems. These probabilities are important in many fields of study, including statistics, finance, and engineering, as they often yield valuable information about the large fluctuations of a random system around its most probable state or trajectory. In the context of equilibrium statistical mechanics, the theory of large deviations provides exponential-order estimates of probabilities that refine and generalize Einstein's theory of fluctuations. This review explores this and other connections between large deviation theory and statistical mechanics, in an effort to show that the mathematical language of statistical mechanics is the language of large deviation theory. The first part of the review presents the basics of large deviation theory, and works out many of its classical applications related to sums of random variables and Markov processes. The second part goes through many problems and results of statistical mechanics, and shows how these can be formulated and derived within the context of large deviation theory. The problems and results treated cover a wide range of physical systems, including equilibrium many-particle systems, noise-perturbed dynamics, nonequilibrium systems, as well as multifractals, disordered systems, and chaotic systems. This review also covers many fundamental aspects of statistical mechanics, such as the derivation of variational principles characterizing equilibrium and nonequilibrium states, the breaking of the Legendre transform for nonconcave entropies, and the characterization of nonequilibrium fluctuations through fluctuation relations.

  16. Large Scale Computations in Air Pollution Modelling

    DEFF Research Database (Denmark)

    Zlatev, Z.; Brandt, J.; Builtjes, P. J. H.

    Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998......Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998...

  17. Reflections on Teaching a Large Class.

    Science.gov (United States)

    Miner, Rick

    1992-01-01

    Uses an analysis of small- and large-class differences as a framework for planning for and teaching a large class. Analyzes the process of developing and offering an organizational behavior class to 141 college students. Suggests ways to improve teaching effectiveness by minimizing psychological and physical distances, redistributing resources,…

  18. Superconducting magnets technologies for large accelerator

    International Nuclear Information System (INIS)

    Ogitsu, Toru

    2017-01-01

    The first hadron collider with superconducting magnet technologies was built at Fermi National Accelerator Laboratory as TEVATRON. Since then, the superconducting magnet technologies are widely used in large accelerator applications. The paper summarizes the superconducting magnet technologies used for large accelerators. (author)

  19. Automating large-scale reactor systems

    International Nuclear Information System (INIS)

    Kisner, R.A.

    1985-01-01

    This paper conveys a philosophy for developing automated large-scale control systems that behave in an integrated, intelligent, flexible manner. Methods for operating large-scale systems under varying degrees of equipment degradation are discussed, and a design approach that separates the effort into phases is suggested. 5 refs., 1 fig

  20. Comb-drive actuators for large displacements

    NARCIS (Netherlands)

    Legtenberg, Rob; Legtenberg, R.; Groeneveld, A.W.; Elwenspoek, Michael Curt

    The design, fabrication and experimental results of lateral-comb-drive actuators for large displacements at low driving voltages is presented. A comparison of several suspension designs is given, and the lateral large deflection behaviour of clamped-clamped beams and a folded flexure design is

  1. Large-scale perspective as a challenge

    NARCIS (Netherlands)

    Plomp, M.G.A.

    2012-01-01

    1. Scale forms a challenge for chain researchers: when exactly is something ‘large-scale’? What are the underlying factors (e.g. number of parties, data, objects in the chain, complexity) that determine this? It appears to be a continuum between small- and large-scale, where positioning on that

  2. Computing in Large-Scale Dynamic Systems

    NARCIS (Netherlands)

    Pruteanu, A.S.

    2013-01-01

    Software applications developed for large-scale systems have always been difficult to de- velop due to problems caused by the large number of computing devices involved. Above a certain network size (roughly one hundred), necessary services such as code updating, topol- ogy discovery and data

  3. Decentralized Large-Scale Power Balancing

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Jørgensen, John Bagterp; Poulsen, Niels Kjølstad

    2013-01-01

    problem is formulated as a centralized large-scale optimization problem but is then decomposed into smaller subproblems that are solved locally by each unit connected to an aggregator. For large-scale systems the method is faster than solving the full problem and can be distributed to include an arbitrary...

  4. Large Mines and the Community : Socioeconomic and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 janv. 2001 ... Large Mines and the Community : Socioeconomic and Environmental Effects in Latin America, Canada, and Spain. Couverture du livre Large Mines and the Community : Socioeconomic and Environmental Effects in Latin America. Directeur(s):. Gary McMahon et Felix Remy. Maison(s) d'édition: Banque ...

  5. The algebras of large N matrix mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Halpern, M.B.; Schwartz, C.

    1999-09-16

    Extending early work, we formulate the large N matrix mechanics of general bosonic, fermionic and supersymmetric matrix models, including Matrix theory: The Hamiltonian framework of large N matrix mechanics provides a natural setting in which to study the algebras of the large N limit, including (reduced) Lie algebras, (reduced) supersymmetry algebras and free algebras. We find in particular a broad array of new free algebras which we call symmetric Cuntz algebras, interacting symmetric Cuntz algebras, symmetric Bose/Fermi/Cuntz algebras and symmetric Cuntz superalgebras, and we discuss the role of these algebras in solving the large N theory. Most important, the interacting Cuntz algebras are associated to a set of new (hidden!) local quantities which are generically conserved only at large N. A number of other new large N phenomena are also observed, including the intrinsic nonlocality of the (reduced) trace class operators of the theory and a closely related large N field identification phenomenon which is associated to another set (this time nonlocal) of new conserved quantities at large N.

  6. The large deviation approach to statistical mechanics

    Science.gov (United States)

    Touchette, Hugo

    2009-07-01

    The theory of large deviations is concerned with the exponential decay of probabilities of large fluctuations in random systems. These probabilities are important in many fields of study, including statistics, finance, and engineering, as they often yield valuable information about the large fluctuations of a random system around its most probable state or trajectory. In the context of equilibrium statistical mechanics, the theory of large deviations provides exponential-order estimates of probabilities that refine and generalize Einstein’s theory of fluctuations. This review explores this and other connections between large deviation theory and statistical mechanics, in an effort to show that the mathematical language of statistical mechanics is the language of large deviation theory. The first part of the review presents the basics of large deviation theory, and works out many of its classical applications related to sums of random variables and Markov processes. The second part goes through many problems and results of statistical mechanics, and shows how these can be formulated and derived within the context of large deviation theory. The problems and results treated cover a wide range of physical systems, including equilibrium many-particle systems, noise-perturbed dynamics, nonequilibrium systems, as well as multifractals, disordered systems, and chaotic systems. This review also covers many fundamental aspects of statistical mechanics, such as the derivation of variational principles characterizing equilibrium and nonequilibrium states, the breaking of the Legendre transform for nonconcave entropies, and the characterization of nonequilibrium fluctuations through fluctuation relations.

  7. Efficient querying of large process model repositories

    NARCIS (Netherlands)

    Jin, Tao; Wang, Jianmin; La Rosa, M.; Hofstede, ter A.H.M.; Wen, Lijie

    2013-01-01

    Recent years have seen an increased uptake of business process management technology in industries. This has resulted in organizations trying to manage large collections of business process models. One of the challenges facing these organizations concerns the retrieval of models from large business

  8. Evaluation Of Electricity Production Cost Of Commercial Nuclear Power Plant Models

    OpenAIRE

    DÖNER, Nimeti

    2017-01-01

    The level of the development of countries is being measured by thecountry’s quantity of production and consumption energy. Concerning Turkey,according to an energy report of The World Energy Council Turkish NationalCommittee in order to meet the electricity needs of the country in 2010, there should befounded a 2000 MW(e) capacity nuclear power plant. For the nuclear electric powerplant considered to be founded in Turkey, three types of commercial reactor models,that are Pressiued Water React...

  9. Environmental effects and large space systems

    Science.gov (United States)

    Garrett, H. B.

    1981-01-01

    When planning large scale operations in space, environmental impact must be considered in addition to radiation, spacecraft charging, contamination, high power and size. Pollution of the atmosphere and space is caused by rocket effluents and by photoelectrons generated by sunlight falling on satellite surfaces even light pollution may result (the SPS may reflect so much light as to be a nuisance to astronomers). Large (100 Km 2) structures also will absorb the high energy particles that impinge on them. Altogether, these effects may drastically alter the Earth's magnetosphere. It is not clear if these alterations will in any way affect the Earth's surface climate. Large structures will also generate large plasma wakes and waves which may cause interference with communications to the vehicle. A high energy, microwave beam from the SPS will cause ionospheric turbulence, affecting UHF and VHF communications. Although none of these effects may ultimately prove critical, they must be considered in the design of large structures.

  10. Entanglement transitions induced by large deviations

    Science.gov (United States)

    Bhosale, Udaysinh T.

    2017-12-01

    The probability of large deviations of the smallest Schmidt eigenvalue for random pure states of bipartite systems, denoted as A and B , is computed analytically using a Coulomb gas method. It is shown that this probability, for large N , goes as exp[-β N2Φ (ζ ) ] , where the parameter β is the Dyson index of the ensemble, ζ is the large deviation parameter, while the rate function Φ (ζ ) is calculated exactly. Corresponding equilibrium Coulomb charge density is derived for its large deviations. Effects of the large deviations of the extreme (largest and smallest) Schmidt eigenvalues on the bipartite entanglement are studied using the von Neumann entropy. Effect of these deviations is also studied on the entanglement between subsystems 1 and 2, obtained by further partitioning the subsystem A , using the properties of the density matrix's partial transpose ρ12Γ. The density of states of ρ12Γ is found to be close to the Wigner's semicircle law with these large deviations. The entanglement properties are captured very well by a simple random matrix model for the partial transpose. The model predicts the entanglement transition across a critical large deviation parameter ζ . Log negativity is used to quantify the entanglement between subsystems 1 and 2. Analytical formulas for it are derived using the simple model. Numerical simulations are in excellent agreement with the analytical results.

  11. Analysis of large databases in vascular surgery.

    Science.gov (United States)

    Nguyen, Louis L; Barshes, Neal R

    2010-09-01

    Large databases can be a rich source of clinical and administrative information on broad populations. These datasets are characterized by demographic and clinical data for over 1000 patients from multiple institutions. Since they are often collected and funded for other purposes, their use for secondary analysis increases their utility at relatively low costs. Advantages of large databases as a source include the very large numbers of available patients and their related medical information. Disadvantages include lack of detailed clinical information and absence of causal descriptions. Researchers working with large databases should also be mindful of data structure design and inherent limitations to large databases, such as treatment bias and systemic sampling errors. Withstanding these limitations, several important studies have been published in vascular care using large databases. They represent timely, "real-world" analyses of questions that may be too difficult or costly to address using prospective randomized methods. Large databases will be an increasingly important analytical resource as we focus on improving national health care efficacy in the setting of limited resources.

  12. Recent quality of ultra large rotor shafts

    International Nuclear Information System (INIS)

    Suzuki, Akira; Kinoshita, Shushi; Morita, Kikuo; Kikuchi, Hideo; Takada, Masayoshi

    1983-01-01

    Large size and high quality are required for rotor shafts accompanying recent trend of thermal and nuclear power generation toward large capacity. As for the low pressure rotor shafts for large capacity turbines, the disks and a shaft tend to be made into one body instead of conventional shrink fit construction, because of the experience of rotor accidents and the improvement of reliability. Therefore the ingots required become more and more large, and excellent production techniques are required for steel making, forging and heat treatment. Kobe Steel Ltd. have made about 20 large generator shafts from 420 t and 500 t ingots, and confirmed their stable high quality. Also a one-body low pressure rotor of 2600 mm diameter was made for trial, and its quality was examined. It was confirmed that the effect of forging and heat treatment was given sufficiently, and the production techniques for super-large one-body rotors were established. In steel making, vacuum degassing was applied twice to decrease hydrogen content, and VV restriction forging and pre-stage treatment were carried out. The properties of large rotors are reported. (Kako, I.)

  13. Distributed simulation of large computer systems

    International Nuclear Information System (INIS)

    Marzolla, M.

    2001-01-01

    Sequential simulation of large complex physical systems is often regarded as a computationally expensive task. In order to speed-up complex discrete-event simulations, the paradigm of Parallel and Distributed Discrete Event Simulation (PDES) has been introduced since the late 70s. The authors analyze the applicability of PDES to the modeling and analysis of large computer system; such systems are increasingly common in the area of High Energy and Nuclear Physics, because many modern experiments make use of large 'compute farms'. Some feasibility tests have been performed on a prototype distributed simulator

  14. Large scale network-centric distributed systems

    CERN Document Server

    Sarbazi-Azad, Hamid

    2014-01-01

    A highly accessible reference offering a broad range of topics and insights on large scale network-centric distributed systems Evolving from the fields of high-performance computing and networking, large scale network-centric distributed systems continues to grow as one of the most important topics in computing and communication and many interdisciplinary areas. Dealing with both wired and wireless networks, this book focuses on the design and performance issues of such systems. Large Scale Network-Centric Distributed Systems provides in-depth coverage ranging from ground-level hardware issu

  15. The Amateurs' Love Affair with Large Datasets

    Science.gov (United States)

    Price, Aaron; Jacoby, S. H.; Henden, A.

    2006-12-01

    Amateur astronomers are professionals in other areas. They bring expertise from such varied and technical careers as computer science, mathematics, engineering, and marketing. These skills, coupled with an enthusiasm for astronomy, can be used to help manage the large data sets coming online in the next decade. We will show specific examples where teams of amateurs have been involved in mining large, online data sets and have authored and published their own papers in peer-reviewed astronomical journals. Using the proposed LSST database as an example, we will outline a framework for involving amateurs in data analysis and education with large astronomical surveys.

  16. Electronic and atomic impacts on large clusters

    International Nuclear Information System (INIS)

    Gspann, J.

    1982-01-01

    Describing first the generation and properties of molecular beams of large Van der Waals clusters such as speed distribution, cluster size distribution, and internal temperature of the clusters, the review then features the results of electronic impacts on large clusters: metastable electronic cluster excitations, ejection of positive cluster ions of less than 100 atoms from much larger parent clusters, and ionization of the large clusters. Atomic impacts at thermal energies are treated with respect to the scattering cross section of the clusters, their drag coefficient in free molecular flow, and the peculiarities of impacts on helium clusters of either isotope. (Auth.)

  17. Large polarons in lead halide perovskites

    OpenAIRE

    Miyata, Kiyoshi; Meggiolaro, Daniele; Trinh, M. Tuan; Joshi, Prakriti P.; Mosconi, Edoardo; Jones, Skyler C.; De Angelis, Filippo; Zhu, X.-Y.

    2017-01-01

    Lead halide perovskites show marked defect tolerance responsible for their excellent optoelectronic properties. These properties might be explained by the formation of large polarons, but how they are formed and whether organic cations are essential remain open questions. We provide a direct time domain view of large polaron formation in single-crystal lead bromide perovskites CH3NH3PbBr3 and CsPbBr3. We found that large polaron forms predominantly from the deformation of the PbBr3 ? framewor...

  18. Laparoscopic transperitoneal ureterolithotomy for large ureteric stones

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Sayyad

    2012-01-01

    Conclusion: Laparoscopic transperitoneal ureterolithotomy is a safe and effective approach for selected patients with large proximal ureteric stones with reduced postoperative pain and short hospital stay, and should be considered as a treatment option for such stones.

  19. Large-scale numerical simulations of plasmas

    International Nuclear Information System (INIS)

    Hamaguchi, Satoshi

    2004-01-01

    The recent trend of large scales simulations of fusion plasma and processing plasmas is briefly summarized. Many advanced simulation techniques have been developed for fusion plasmas and some of these techniques are now applied to analyses of processing plasmas. (author)

  20. Large Truck Crash Causation Study (LTCCS)

    Data.gov (United States)

    Department of Transportation — The Large Truck* Crash Causation Study (LTCCS) is based on a three-year data collection project conducted by the Federal Motor Carrier Safety Administration (FMCSA)...

  1. A large-scale study of misophonia

    NARCIS (Netherlands)

    Rouw, R.; Erfanian, M.

    2018-01-01

    Objective We aim to elucidate misophonia, a condition in which particular sounds elicit disproportionally strong aversive reactions. Method A large online study extensively surveyed personal, developmental, and clinical characteristics of over 300 misophonics. Results Most participants indicated

  2. The Expanded Very Large Array Project

    Science.gov (United States)

    Perley, Rick

    2012-10-01

    The Expanded Very Large Array Project, begun in 2001, is now completed -- on time, on budget, and ``on spec.'' The major goal of the project was to multiply the key observational capabilities of the Very Large Array -- the world's most powerful, versatile, and productive radio telescope -- by a factor of at least an order of magnitude by implementation of modern technologies. The result of the project is an operationally new telescope -- renamed the Jansky Very Large Array -- which is capable of new science unimagined in 1980, when the original VLA was completed. In this talk, I will review the goals of the project, and describe the new capabilities of the Jansky Very Large Array. Already, the array is providing fabulous new insights into the physics of the universe,and I will spend the majority of the time describing examples of new results.

  3. Nonlinear continuum mechanics and large inelastic deformations

    CERN Document Server

    Dimitrienko, Yuriy I

    2010-01-01

    This book provides a rigorous axiomatic approach to continuum mechanics under large deformation. In addition to the classical nonlinear continuum mechanics - kinematics, fundamental laws, the theory of functions having jump discontinuities across singular surfaces, etc. - the book presents the theory of co-rotational derivatives, dynamic deformation compatibility equations, and the principles of material indifference and symmetry, all in systematized form. The focus of the book is a new approach to the formulation of the constitutive equations for elastic and inelastic continua under large deformation. This new approach is based on using energetic and quasi-energetic couples of stress and deformation tensors. This approach leads to a unified treatment of large, anisotropic elastic, viscoelastic, and plastic deformations. The author analyses classical problems, including some involving nonlinear wave propagation, using different models for continua under large deformation, and shows how different models lead t...

  4. Large-scale computing with Quantum Espresso

    International Nuclear Information System (INIS)

    Giannozzi, P.; Cavazzoni, C.

    2009-01-01

    This paper gives a short introduction to Quantum Espresso: a distribution of software for atomistic simulations in condensed-matter physics, chemical physics, materials science, and to its usage in large-scale parallel computing.

  5. Swarm Manipulation of Large Surface Vessels

    National Research Council Canada - National Science Library

    Smith, Erik T

    2007-01-01

    The goal of this Trident project was to develop an independent control scheme to allow a team of autonomous tugboats to move a large disabled vessel, such as a barge, to a desired position and orientation...

  6. South African red data book - large mammals

    CSIR Research Space (South Africa)

    Skinner, JD

    1977-11-01

    Full Text Available Data sheets are provided for 22 threatened South African large mammals, one exterminated (Liechtenstein1s hartebeest), eight endangered (cheetah, hunting dog, dugong, Cape mountain zebra, black rhinoceros, tsessebe, roan antelope, suni), one...

  7. Computational Modeling of Large Wildfires: A Roadmap

    KAUST Repository

    Coen, Janice L.; Douglas, Craig C.

    2010-01-01

    Wildland fire behavior, particularly that of large, uncontrolled wildfires, has not been well understood or predicted. Our methodology to simulate this phenomenon uses high-resolution dynamic models made of numerical weather prediction (NWP) models

  8. Remotely controlled large container disposal methodology

    International Nuclear Information System (INIS)

    Amir, S.J.

    1994-09-01

    Remotely Handled Large Containers (RHLC), also called drag-off boxes, have been used at the Hanford Site since the 1940s to dispose of large pieces of radioactively contaminated equipment. These containers are typically large steel-reinforced concrete boxes, which weigh as much as 40 tons. Because large quantities of high-dose waste can produce radiation levels as high as 200 mrem/hour at 200 ft, the containers are remotely handled (either lifted off the railcar by crane or dragged off with a cable). Many of the existing containers do not meet existing structural and safety design criteria and some of the transportation requirements. The drag-off method of pulling the box off the railcar using a cable and a tractor is also not considered a safe operation, especially in view of past mishaps

  9. Large-bandwidth planar photonic crystal waveguides

    DEFF Research Database (Denmark)

    Søndergaard, Thomas; Lavrinenko, Andrei

    2002-01-01

    A general design principle is presented for making finite-height photonic crystal waveguides that support leakage-free guidance of light over large frequency intervals. The large bandwidth waveguides are designed by introducing line defects in photonic crystal slabs, where the material in the line...... defect has appropriate dispersion properties relative to the photonic crystal slab material surrounding the line defect. A three-dimensional theoretical analysis is given for large-bandwidth waveguide designs based on a silicon-air photonic crystal slab suspended in air. In one example, the leakage......-free single-mode guidance is found for a large frequency interval covering 60% of the photonic band-gap....

  10. Large Area Sputter Coating on Glass

    Science.gov (United States)

    Katayama, Yoshihito

    Large glass has been used for commercial buildings, housings and vehicles for many years. Glass size for flat displays is getting larger and larger. The glass for the 8th generation is more than 5 m2 in area. Demand of the large glass is increasing not only in these markets but also in a solar cell market growing drastically. Therefore, large area coating is demanded to plus something else on glass more than ever. Sputtering and pyrolysis are the major coating methods on large glass today. Sputtering process is particularly popular because it can deposit a wide variety of materials in good coating uniformity on the glass. This paper describes typical industrial sputtering system and recent progress in sputtering technology. It also shows typical coated glass products in architectural, automotive and display fields and comments on their functions, film stacks and so on.

  11. Large-scale regions of antimatter

    International Nuclear Information System (INIS)

    Grobov, A. V.; Rubin, S. G.

    2015-01-01

    Amodified mechanism of the formation of large-scale antimatter regions is proposed. Antimatter appears owing to fluctuations of a complex scalar field that carries a baryon charge in the inflation era

  12. Large-scale regions of antimatter

    Energy Technology Data Exchange (ETDEWEB)

    Grobov, A. V., E-mail: alexey.grobov@gmail.com; Rubin, S. G., E-mail: sgrubin@mephi.ru [National Research Nuclear University MEPhI (Russian Federation)

    2015-07-15

    Amodified mechanism of the formation of large-scale antimatter regions is proposed. Antimatter appears owing to fluctuations of a complex scalar field that carries a baryon charge in the inflation era.

  13. Innovation Initiatives in Large Software Companies

    DEFF Research Database (Denmark)

    Edison, Henry; Wang, Xiaofeng; Jabangwe, Ronald

    2018-01-01

    empirical studies on innovation initiative in the context of large software companies. A total of 7 studies are conducted in the context of large software companies, which reported 5 types of initiatives: intrapreneurship, bootlegging, internal venture, spin-off and crowdsourcing. Our study offers three......Context: To keep the competitive advantage and adapt to changes in the market and technology, companies need to innovate in an organised, purposeful and systematic manner. However, due to their size and complexity, large companies tend to focus on the structure in maintaining their business, which...... can potentially lower their agility to innovate. Objective:The aims of this study are to provide an overview of the current research on innovation initiatives and to identify the challenges of implementing those initiatives in the context of large software companies. Method: The investigation...

  14. Production of baryons with large transverse momentum

    International Nuclear Information System (INIS)

    Landshoff, P.V.; Polkinghorne, J.C.; Scott, D.M.

    1975-01-01

    The multiple scattering of constituent quarks provides a natural mechanism for fairly copious production of large-transverse-momentum baryons in nucleon--nucleon collisions. The predicted scaling law agrees well with available data, and the mechanism provides a qualitative explanation of nuclear-target effects. In comparison with previous parton models, correlations are predicted to be qualitatively different, and large-p/sub T/ baryon production by meson beams is relatively suppressed

  15. Neutrino bi-large mixings and family

    International Nuclear Information System (INIS)

    Bando, Masako; Obara, Midori

    2004-01-01

    After a brief review of quark-lepton relations in grand unified theories (GUT), we show that the Pati-Salam relation with only one type of Higgs field configuration with ''four zero symmetric texture'' can reproduce two large neutrino mixings as well as observed mass differences. This is quite in contrast to the case of SU(5) where bi-large mixings essentially come from the charged lepton sector with non-symmetric charged lepton mass matrix. (author)

  16. Cruas site: inception of 'large jobsite' procedure

    International Nuclear Information System (INIS)

    Bottini, R.

    1980-01-01

    In France, the construction sites of nuclear plants are governed by a series of government decisions approved in July 1975 relating to so-called 'large jobsites of territorial improvements'. Using as an example the 'large jobsite' of the Cruas plant, now under construction, the author illustrates the practical application of the considered procedure, amongst others from the standpoints of organization measures and the quality of the living conditions of workers [fr

  17. LYCORIS - A Large Area Strip Telescope

    CERN Document Server

    Krämer, U; Stanitzki, M; Wu, M

    2018-01-01

    The LYCORIS Large Area Silicon Strip Telescope for the DESY II Test Beam Facility is presented. The DESY II Test Beam Facility provides elec- tron and positron beams for beam tests of up to 6 GeV. A new telescope with a large 10 × 20 cm2 coverage area based on a 25 μm pitch strip sensor is to be installed within the PCMAG 1 T solenoid. The current state of the system is presented.

  18. Transport Coefficients from Large Deviation Functions

    OpenAIRE

    Gao, Chloe Ya; Limmer, David T.

    2017-01-01

    We describe a method for computing transport coefficients from the direct evaluation of large deviation functions. This method is general, relying on only equilibrium fluctuations, and is statistically efficient, employing trajectory based importance sampling. Equilibrium fluctuations of molecular currents are characterized by their large deviation functions, which are scaled cumulant generating functions analogous to the free energies. A diffusion Monte Carlo algorithm is used to evaluate th...

  19. A very large multigap resistive plate chamber

    CERN Document Server

    Cerron-Zeballos, E; Hatzifotiadou, D; Kim, D W; Lamas-Valverde, J; Lee, S C; Platner, E D; Roberts, J; Williams, M C S; Zichichi, A

    1999-01-01

    We have built and tested a very large multigap resistive plate chamber (MRPC). We discuss the suitability of the multigap RPC for the construction of large area modules. We give details of the construction technique and results from a scan across the surface of the chamber. We also report on the implementation of `half-strip resolution', where we improve the spatial resolution by a factor 2 without increasing the number of read-out channels. (9 refs).

  20. Vanishing large ovarian cyst with thyroxine therapy

    OpenAIRE

    Dharmshaktu, Pramila; Kutiyal, Aditya; Dhanwal, Dinesh

    2013-01-01

    Summary A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the cond...