The management procedure of a large PRISE (Primary-to-Secondary) leakage accident at Loviisa nuclear power plant taking into account the plant modifications which are expected to be realized during 1995-96 is described. The management procedure has been validated by performing thermal hydraulic analyses with the computer code RELAP5/MOD3 and the results from these analyses are also shortly discussed. (4 refs., 6 figs., 1 tab.).
During the past few years, the dual role that ozone plays in climate change has been becoming increasingly obvious. First, continuous thinning of the ozone layer has been evident, even in the high and middle latitudes in the northern hemisphere. Secondly, ozone is also a greenhouse gas, affecting radiative transfer. Increases in tropospheric ozone have a positive forcing, whereas decreases in stratospheric ozone cause a negative forcing. During the last six years, measurements on total ozone and the vertical distribution of ozone have been performed at the Sodankylae Observatory. At Jokioinen Observatory, measurements on total ozone have been performed since 1990 and measurements on the vertical distribution of ozone since 1993. The overall project has focused on extending the national data series on total ozone and the vertical distribution of ozone. At the same time, the study has contributed to the study of interannual variability of the ozone layer. This SILMU project took part in ...
Since 1994-95 the University of Applied Sciences Berne is working on weather-proof electric bicycles. The main drawbacks of bicycles, no weather-protection, little comfort of the saddle, the difficulty of climbing hills, are to be eliminated. The electro-mechanical drive-train of 'Ultraleichtmobil ULM BE 2000', developed in 1995-96, was mechanically complicated. This resulted in reduced energy-efficiency and intense maintenance. Too, the drive-train was expensive in production. A fully electrical human-power transmission seemed to be the solution to the problems mentioned above. It is appealing not only to the user of the vehicle, but also to the producer and to the persons doing the maintenance. Following an internal study showing the technical feasibility of such an electrical transmission, a controllable DC/DC-converter which allows to operate a pedal-driven generator at maximum efficiency has been developed. The electrical transmission is the ...
The Ohio State University Research Reactor (OSURR) is licensed to operate at a maximum power level of 500 kW. A pool-type reactor using flat-plate, low enriched fuel elements, the OSURR provides several experimental facilities including two 6-inch i.d. beam ports, a graphite thermal column, several graphite-isotope-irradiation elements, a pneumatic transfer system (Rabbit), various dry tubes, and a Central Irradiation Facility (CIF). The core arrangement and accessibility facilitates research programs involving material activation or core parameter studies. The OSURR control room is large enough to accommodate laboratory groups which can use control instrumentation for monitoring of experiments. The control instrumentation is relatively simple, without a large amount of duplication. This facilitates opportunities for hands-on experience in reactor operation by nuclear engineering students making reactor ...
An estimator for the load share parameters in an equal load-share model is derived based on observing k-component parallel systems of identical components that have a continuous...Full Text Available
Nuclear energy plays an important role in electricity generation, producing 16% of the world's electricity at the beginning of 1999. It has proven to be safe, reliable, economical and has only a minimal impact on the environment. Most of the world's energy consumption, however, is in the form of heat. The market potential for nuclear heat was recognized early. Some of the first reactors were used for heat supply, e.g. Calder Hall (United Kingdom), Obninsk (Russian Federation), and Agesta (Sweden). Now, over 60 reactors are supplying heat for district heating, industrial processes and seawater desalination. But the nuclear option could be better deployed if it would provide a larger share of the heat market. In particular, seawater desalination using nuclear heat is of increasing interest to some IAEA Member States. In consideration of the growing experience being accumulated, the IAEA periodically reviews the progress and ...
The procedure and operation-by-operation methods of the quality control of structural and fuel materials, mixed fuel pellets of UO_2-PuO_2, fuel element cans made of the AISI-316 steel and ready fuel elements are described as well as spacer wires (steel AISI-316), cases of fuel assemblies (FA) and completed FAs. The methods are used in manifacturing fuel elements and FAs for the FFTF reactor. The RDT standards that regulate the structure and functioning of the system of fuel element and FA production management are outlined. Destructive analytical methods characterized by sufficient accuracy but low productivity are noted to represent a considerable share of operations. Some specialized means of nondestructive testing are developed, such as the gauge to measure the total plutonium content in a fuel element, neutron radiography deVice and a laser gauge to measure the FA dimensions. The experience gained served as a basis for designing the ...
The procedure and operation-by-operation methods of the quality control of structural and fuel materials, mixed fuel pellets of UO/sub 2/-PuO/sub 2/, fuel element cans made of the AISI-316 steel and ready fuel elements are described as well as spacer wires (steel AISI-316), cases of fuel assemblies (FA) and completed FAs. The methods are used in manifacturing fuel elements and FAs for the FFTF reactor. The RDT standards that regulate the structure and functioning of the system of fuel element and FA production management are outlined. Destructive analytical methods characterized by sufficient accuracy but low productivity are noted to represent a considerable share of operations. Some specialized means of nondestructive testing are developed, such as the gauge to measure the total plutonium content in a fuel element, neutron radiography deVice and a laser gauge to measure the FA dimensions. The experience gained served as a basis for designing ...
BackgroundCo-flowering plant species frequently share pollinators. Pollinator sharing is often detrimental to one or more of these species, leading to competition for pollination....Full Text Available
The present work mainly involves bench scale studies to investigate partitioning of mercury in pulverized fuel co-combustion at 1000 and 1300{sup o}C. High volatile bituminous coal is used as a reference case and chicken manure, olive residue, and B quality (demolition) wood are used as secondary fuels with 10 and 20% thermal shares. The combustion experiments are carried out in an entrained flow reactor with a fuel input of 7-8 kWth. Elemental and total gaseous mercury concentrations in the flue gas of the reactor are measured on-line, and ash is analyzed for particulate mercury along with other elemental and surface properties. Animal waste like chicken manure behaves very differently from plant waste. The higher chlorine contents of chicken manure cause higher ionic mercury concentrations whereas even with high unburnt carbon, particulate mercury reduces with increase in the chicken manure share. ...
Aliasing, or sharing, is prominent in many domains, denoting that two differently-named objects are in fact identical: a change in one object (memory cell, circuit terminal, disk block) is instantly reflected in the other. Languages for modelling such domains should let the programmer explicitly define the sharing among objects or expressions. A DSL compiler may find other identical expressions and share them, implicitly. Such common subexpression elimination is crucial to the efficient implementation of DSLs. Sharing is tricky in embedded DSL, since host aliasing may correspond to copying of the underlying objects rather than their sharing. This tutorial summarizes discussions of implementing sharing in Haskell DSLs for automotive embedded systems and hardware description languages. The technique has since been used in a Haskell SAT solver and the DSL for music ...
Considering the present situation of thermal energy in Romania and having in view the fact that Romania is a Kyoto protocol signatory state one estimates that the development of the nuclear energy will have a promising growth. According with the statement of the National Energetic Observer, Romania became a net energy resource importer for the past 30 years and the estimations about the future are not optimistic. The finite reserves of fossil fuel (coal and natural gas), the gradual reduction of their share in the national energy balance with a tendency to become insignificant after 2025, as well as the present situation of the thermal power plants which are already beyond their operation life, all these indicate the nuclear energy as being the most reliable and sustainable future source for thermal energy production. Having in view these circumstances the paper aims at a short presentation of the existing nuclear solutions for district heating. Also, reviewed are ...
Standardization enhances: international cooperation; development of new nuclear techniques and technologies; characterization and checking procedures of equipment; sharing a common terminology. A historical sketch is given focussing: inception of standardization in electro-techniques at international scale; organization of the International Electrotechnical Commission, IEC; - current aspects of nuclear equipment standardization; activity of seven working groups devoted to nuclear reactor equipment; activity of seven groups working on radioprotection equipment; activity of four groups working on nuclear equipment. ISO organization and present issues concerning the nuclear technology development in Romania. It is presented the activity in the frame of CENELEC, CLC/TC45, for endorsing the IEC/TC45B standards. In 2007 a CENELEC/ BTT 127-1 working commission was formed to enhance assimilation of IEC /TC45 A standards in EU concerning the ...
A comparative and quantitative study of the tissue distribution of brain-thymus shared antigens was carried out using rabbit antisera to rat, dog and human brain homogenates, assayed on rat, dog and...Full Text Available
As the IC Information Sharing Executive (IC ISE), my main focus today concerns classified information--and, in particular, information that is derived from intelligence sources and methods, or information that is reflected in the analytic judgments and as...
The induction of voltages on pipelines and railroad signal wires can be a problem when high-voltage transmission lines share the right of way. A handbook and two computer programs provide the analytic tools for utilities to avoid the problem.
sharing data and computational resources, and accessing information in digital libraries." Bill Wulf (1989) In a Collaboratory, the presentation/meeting concept embodied...
To permit an assessment of the system presented in this paper the data collected up to this point should be complemented by further experience with its practical use in electromobiles and the recovery of zink and the electrolyte. To this end the system is to be tested in electromobiles in 1995 and 1996. If there are no serious problems in the course of these tests and the above-mentioned estimates on economic efficiency are confirmed, then there is much to be said for a large-scale trial of these battery systems in electromobiles in the framework of a pilot project in Karlsruhe. Because of the infrastructure required for recharging, such a project should first be carried out in cooperation with fleet operators. As the recharging technique employed is so simple as to require no great investment and cost-effectiveness should already be achievable with a few tens of vehicles, one can conceive of a whole variety of applications in cooperation with public utilities, municipalities, and ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts ...
In single-qubit quantum secret sharing, a secret is shared between N parties via manipulation and measurement of one qubit at a time. Each qubit is sent to all N parties in sequence; the secret is encoded in the first participant's preparation of the qubit state and the subsequent participants' choices of state rotation or measurement basis. We present a protocol for single-qubit quantum secret sharing using polarization entanglement of photon pairs produced in type-I spontaneous parametric downconversion. We investigate the protocol's security against eavesdropping attack under common experimental conditions: a lossy channel for photon transmission, and imperfect preparation of the initial qubit state. A protocol which exploits entanglement between photons, rather than simply polarization correlation, is more robustly secure. We implement the entanglement-based secret-sharing protocol with 87% ...
... These highly energy efficient panels of organic luminescence are far removed from the bulbs and filaments of current lighting technology. 28-04-11 Source : Star Projects Results: 1-10 of 251 Page(s) 1 of 26 Next Limit search to articles published within the last Month Quarter Year No limit Follow us on Facebook Share an article You can share any article via social networking sites or email it to friends. Click the SHARE icon, select from the list that appears, and the article ...
The role of computers has become increasingly important for oil and gas field research and operations support. Today, the computer network is an integral part of the increasingly complex computing environment that exists in many companies. Computer networks allow users to efficiently share information, software, and hardware to support critical global communication needs. Because users are able to share software and hardware, the use of computer networks can also result in significant cost savings. This paper describes typical network loading and demand levels for shared software applications on a computer network that has been used for several years.
The difficult economic circumstances with which almost the whole world had to contend, brought serious financial crisis in many countries. South Africa also had its own share of serious problems. Despite this situation, Transvaal Consolidated Land and Exploration Company, Limited, showed on increase in earnings of 24 per cent per share. The reason for this lies mainly in two areas. Firstly the company acquired the mining related business of Rand Mines, Limited. Included in the acquisition was a partfolio of shares mainly in the company's associated gold and uranium mining companies and additional shares in its listed coal mining subsidiaries. Secondly, the average gold price realised by producers in rand terms, was considerably higher than in the previous year. Consolidated profit attributable to members increased by 52 per cent to R82,6 million.
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The precautionary principle has provoked a spirited debate among environmentalists worldwide, but it is equally relevant to public health and shares much with primary prevention. Its central components...Full Text Available
A large group of diseases, termed protein misfolding disorders, share the common feature of the accumulation of misfolded proteins. The possibility of a common mechanism underlying either the pathogenesis...Full Text Available
brain Printer-friendly version Email this page to a friend Share Primary lymphoma of the brain is cancer of the lymph cells that starts in the brain. Causes The cause of primary...
Lens-induced glaucoma comprises a number of different glaucomatous processes occurring in the elderly that share in common the role of the crystalline lens in the mechanism of increase in intraocular...Full Text Available
Nativist and constructivist approaches to the study of development share a common emphasis on characterizing beginning and end states in development. This focus has highlighted the question...Full Text Available
of different transportation fuels (e.g., gasoline, diesel fuel, aviation gasoline, jet fuel, residual fuel oil). Subsequent calculations are performed to estimate the share...
Publications Science Highlights Researcher Profiles Internship Funding to push battery technology from Argonne Laboratory to marketplace Bookmark and Share (Download...
In natural ecosystems, hundreds of species typically share the same environment and are connected by a dense network of interactions such as predation or competition for resources. Much is known about...Full Text Available
BackgroundInternet-based depression communities provide a forum for individuals to communicate and share information and ideas. There has been little research into the health status...Full Text Available
The main aim of DNA barcoding is to establish a shared community resource of DNA sequences that can be used for organismal identification and taxonomic clarification. This approach was successfully...Full Text Available
Sep 1, 2011 ... Publication Information. Bookmark and Share. Title: Arc Habitat Suitability Index computer software. Author: Juntti, Thomas M.; Rumble, Mark A. ...
The concentrations of uranium, arsenic, and radium remain well below the maximum permissible values of < 0.1 mg/l (uranium), < 0.1 mg/l (arsenic) and < 100 mBq/l (radium) due to two separation stages with barium sulfate and GoPur 3000 precipitation and due to iron hydroxide/iron arsenate precipitation. The radioactive arsenates can be separated from the toxic ones by separating the sludge which is analyzed. Processing of radioactive sludges leaves reusable GoPur 3000, sulfuric solutions which contain uranium or solutions which contain carbonate, and radioactive barium sulfate whose radiation intensity of 12 mBq/g is due to the presence of radium. The sludge produced contains adsorbed salts in addition to the dosed chemicals (floated sludges: 40 g/m"3, iron sludges < 20 g/m"3). A solids content < 100 g/m"3 can be selected for both sludge portions. Static-mixer chemicals dosing and technical improvements of the tubular reactor are required for ...
As the result of 15 years of research (50 staff years of effort) Argonne National Laboratory (ANL), through its involvement in fluidized-bed combustion, magnetohydrodynamics, and a variety of environmental programs, has produced extensive computational fluid dynamics (CFD) software and models to predict the multiphase hydrodynamic and reactive behavior of fluid-solids motions and interactions in complex fluidized-bed reactors (FBRS) and slurry systems. This has resulted in the FLUFIX, IRF, and SLUFIX computer programs. These programs are based on fluid-solids hydrodynamic models and can predict information important to the designer of atmospheric or pressurized bubbling and circulating FBR, fluid catalytic cracking (FCC) and slurry units to guarantee optimum efficiency with minimum release of pollutants into the environment. This latter issue will become of paramount importance with the enactment of the Clean Air Act Amendment (CAAA) of 1995. Solids motion is also ...
Aging degradation is a phenomenon we all experience throughout life, both on a personal basis and in business. Many industries have been successful in postponing the inevitable impact on their related systems and components through programs to maintain long-term reliability, maintainability and safety. However, this has not always been the case for nuclear power. While all power plants are experiencing the world trend of increasing operating costs with age, few (if any) have been able to fully define the parameters that solve the aging equation, particularly in relation to major components. Inspection and preventive maintenance have not been effective in predicting life-limiting degradation and failure. In CANDU nuclear plants, utilities are taking a comprehensive approach in dealing with the aging problem. Programs have been established to identify the current condition and degradation mechanisms of critical components, the failure of which would impact negatively on station ...
A nuclear power plant engineering (NPP) simulator may include many system functions such as thermal-hydraulic calculation, 3D reactor neutron kinetics model, control and protection system, display and operational human-machine interface, intelligent alarm system, etc. If all those functions are simulated using a single code, the size of the program will cause structural or managerial problems, and the hardware requirement could be tremendous. Thus, any local function errors or changes may affect the whole code, which will make development and maintenance extremely costly. So the nondistributed code is not considered to be flexible and feasible. Currently, distributed and parallel technologies have been applied to develop NPPs engineering simulator for safety analysis, verification of advanced main control room display, operation and intelligent alarm design. The distributed simulation divides a huge task into several objects according to different functions. ...
This study validates a research model that examines usage of instant messaging (IM) from the aspect of online social support. Drawing on the social capital theory, this study postulates that IM usage is indirectly affected by social support via the mediation of the following six dimensions of social capital: commitment, reciprocity, shared codes and language, shared narratives, centrality, and network ties. The model tests data obtained from business organizations in Taiwan, and the results suggest that the indirect influence of social support on IM usage through shared codes and language is significant, and the indirect influence of social support on IM usage through centrality is also significant. Managerial implications and limitations of the empirical findings are provided.
Recent achievements and tendency on reactor physics activities in Japan are reviewed according to topics published in journals or discussed at the Japan Research Committee on Reactor Physics.
... and support cost, and post-retirement disposal cost) of ... from reactors, and the reactors and other ... the ship's hull and reactor compartment enough to ...
AECL Publications on Reactor Safety in CANDU Reactors are listed in this bibliography. The listing is chronological and the accompanying index is by subject. The bibliography will be brought up to date annually. (auth).
PURPOSECost-sharing, intended to control the “over-use” of healthcare resources, may also reduce utilization of necessary services. The influence...Full Text Available
The difficult economic circumstances with which almost the whole world had to contend, brought serious financial crisis in many countries. South Africa also had its own share of serious problems. Despite this situation, Transvaal Consolidated Land and Exploration Company, Limited, showed on increase in earnings of 24 per cent per share. The reason for this lies mainly in two areas. Firstly the company acquired the mining related business of Rand Mines, Limited. Included in the acquisition was a partfolio of shares mainly in the company's associated gold and uranium mining companies and additional shares in its listed coal mining subsidiaries. Secondly, the average gold price realised by producers in rand terms, was considerably higher than in the previous year. Consolidated profit attributable to members increased by 52 per cent to R82,6 million.
The neuronal networks in spinal cord can produce a diverse array of motor behaviors. In aquatic vertebrates such as fishes and tadpoles, these include escape behaviors, swimming across a range...Full Text Available
The phylogeny and taxonomy of mammalian species were originally based upon shared or derived morphological characteristics. However, genetic analyses have more recently played an increasingly important...Full Text Available
BackgroundSmall laboratory fish share many anatomical and histological characteristics with other vertebrates, yet can be maintained in large numbers at low cost for lifetime studies....Full Text Available
The history of the Arabian Gulf region shows a lot of commonality in the six states which form the Gulf Cooperation Council (GCC). Their shared heritage ranges from common colonial masters to common religion and language. Because of their oil wealth and, ...
The developing Integrated Academic Information System (IAIMS) at Columbia-Presbyterian Medical Center provides data sharing links between two separate corporate entities, namely Columbia University...Full Text Available
Petroleum is the unchallenged energy market leader in West Germany,having a share of 42%; natural gas accounts for 16-17%. West Germany imports 29% of its natural gas from the Soviet Union, 28% from the Netherlands, 14% from Norway, and 1% from Denmark. In West Germany many-branched natural gas distribution system is operated, equipped with a.o. 21 installations for underground storage which results in a great flexibility of the system. Because of the preferential treatment given to the use of coal as fuel for power plants the share of natural gas has decreased to the present 6% in the last ten years. In the indutrial sector the share is 18%. Strict air pollution abatement measures ('TA-Luft') favour the use of natural gas. However, duty has been levied on the use of natural gas per January 1st, 1989. For space heating of houses and commercial buildings the share of natural gas is 27%. ...
Equipped with terahertz sensors, the Aura mission will see far more ... We introduce you to a few amazing individuals, all sharing the dubious title of rocket scientist . And a ..... similar thing happens with incoming light. Astronomers call it the ...
Dyslexia (or reading disability) and specific language impairment (or SLI) are common childhood disorders that show considerable co-morbidity and diagnostic overlaps and have been suggested to share...Full Text Available
This paper describes Image Engine, an object-oriented, microcomputer-based, multimedia database designed to facilitate the storage and retrieval of digitized biomedical still images, video, and text...Full Text Available
efforts to work with other countries to solve shared problems. U.S. Condemns Alleged WikiLeaks Disclosures November 29, 2010: President Obama and Secretary of State Hillary Rodham...
Ovine and caprine lentiviruses share the capacity to induce slowly progressive and inflammatory diseases of the central nervous system (leukoencephalitis or visna), lungs (progressive pneumonia or maedi),...Full Text Available
This paper hopes to share the insights we experienced during designing, building, and running an indexing solution for a large set of radiological reports and images in a production environment for...Full Text Available
Tissue microarray technology (TMA) is a relatively new approach for efficiently and economically assessing protein and gene expression across large ensembles of tissue specimens. Tissue microarray technology...Full Text Available
Type 2 diabetes mellitus (DM2) is increasing in incidence, creating worldwide public health concerns and impacting morbidity and mortality rates. An increasing number of studies have demonstrated shared...Full Text Available
Published rates of comorbidity between pediatric bipolar disorder (PBD) and attention-deficit/hyperactivity disorder (ADHD) have been higher than would be expected if they were independent conditions,...Full Text Available
Oligopeptidic drugs such as β-lactams and angiotensin-converting enzyme inhibitors share the same carriers in humans and animals, which results in possible pharmacokinetic interactions. To model...Full Text Available
Amyloid proteins constitute a chemically heterogeneous group of proteins, which share some biophysical and biological characteristics, the principal of which are the high propensity to acquire an incorrect...Full Text Available
BackgroundThe first week of human pre-embryo development is characterized by the induction of totipotency and then pluripotency. The understanding of this delicate process will have...Full Text Available
...COMCAM forces document Air Force and air component activities...supported unified command or joint task force commander, through the...Force COMCAM forces in a joint environment. If an...share of Unified Command headquarters COMCAM and visual...
An overview is presented of the FFTF reactor and plant together with descriptions of core components, core internals, core system, primary and secondary control rod system, reactor instrumentation, reactor vessel and closure head, and supporting test programs. (DG)
An overview is presented of the FFTF reactor and plant together with descriptions of core components, core internals, core system, primary and secondary control rod system, reactor instrumentation, reactor vessel and closure head, and supporting test programs.
Purpose - The article shares insights from a program that was developed to address burnout, compassion fatigue and vicarious trauma. The program works from the premise that people and organizations thrive when they have shared values and common understandings. Design/methodology/approach - The approach draws together reflection at the organizational and person levels. Connecting business ethics and organizational analysis, improving understanding of the body's energy as well as inter-cultural understanding are all achievable while adopting the resilience development methods. Findings - The article concludes that reflective practice through the tools used on the program enhances understanding of the challenges faced by organizations and the individuals involved. It provides creative routes ...
This handbook breaks down the complex field of nuclear reactor calculations into major steps. Each step presents a detailed analysis of the problems to be solved, the parameters involved, and the elaborate computer programs developed to perform the calculations. This book bridges the gap between nuclear reactor theory and the implementation of that theory, including the problems to be encountered and the level of confidence that should be given to the methods described. Volume II: Monte Carlo Calculations for Nuclear Reactors. In-Core Management of Four Reactor Types. In-Core Management in CANDU-PHW Reactors. Reactor Dynamics. The Theory of Neutron Leakage in Reactor Lattices. Index.
Information is presented concerning reactor research activities; isotope geology; NERC radiocarbon laboratory; teaching activities; and reactor operation.
The MEX-15 is a conceptual design of a Multipurpose Reactor with thermal power of 15 MW and this reactor is pool type with fuel plates U{sub 3}0{sub 8}-Al of low enrichment uranium. This report presents the static calculation for the MEX-15 reactor using SRAC code system and was developed under the collaboration agreement between ININ-JAERI in Research Reactor Technology Development Division of Department of Research Reactor in Tokai Research Establishment. (Author)
The TVR heavy water research reactor was deployed at Moscow Institute of Theoretical and Experimental Physics. In 1990, the final batch of the spent nuclear fuel from this reactor was shipped to Production Association (PA) 'Mayak' for reprocessing. The SNF removal was a stage of the reactor decommissioning activities. The designs of the TVR reactor and its fuel elements are similar to the RA reactor designs. Two ways of the RA reactor SNF transportation to PA 'Mayak' have been considered: in aluminum barrels and in additional canisters using respectively TUK-32 and TUK-19 shipping casks. The practical experience and the equipment used to prepare for the TVR reactor SNF removal can be helpful to the RA reactor personnel in finding the best way to perform these engineering operations. (author)
This is the twenty-ninth edition of Reference Data Series No. 2, Nuclear Power Reactors in the World, which is published once per year, and presents the most recent reactor data available to the IAEA. It contains the following summarized information: - General information as of the end of 2008 on power reactors operating or under construction, and shut down; - Performance data on reactors operating in the Agency's Member States, as reported to the IAEA. The IAEA's Power Reactor Information System (PRIS) is a comprehensive data source on nuclear power reactors in the world. It includes specification and performance history data of operating reactors as well as reactors under construction or reactors being decommissioned. PRIS data are collected by the IAEA through the designated national ...
JRR-3 is a research reactor of 10 MWt output, which attained the criticality in 1962. All the design, manufacture, installation and others of this reactor were carried out by Japanese technologies, except the fuel and heavy water as the moderator and coolant, therefore it is nicknamed Home-made No.1 Reactor. Recently, due to the change in the state of utilizing research reactors and the rise of quality in the utilization, JRR-3 has become to be unable to meet sufficiently the needs of users. The plan of reconstructing the JRR-3 was considered under such situation, and in order to reuse the reactor building, the reactor proper is removed, and an entirely new, high performance, versatile reactor is to be constructed. In this paper, as to the removal works of the JRR-3 reactor proper, the method of execution, design, the ...
Fusion energy has been studied in many countries such as U.S., France, Japan, Korea etc. Because it would provide much more energy for a given weight of fuel than any technology currently in use, and the fuel itself (primarily deuterium) exists abundantly in the Earth's ocean. Nuclear fusion reactor uses tritium and deuterium as fuel while nuclear fission reactor uses uranium and plutonium as fuel. Besides, inherent design characteristics and driving condition of nuclear fusion reactor is different from those of nuclear fission reactor. Therefore, we cannot apply the regulation rules of nuclear fission reactor to nuclear fusion reactor without change and thus it is needed to development of the safety regulation concept which reflects the characteristics of nuclear fusion reactor. Safety regulation of nuclear fusion ...
This handbook breaks down the complex field of nuclear reactor calculations into major steps. Each step presents a detailed analysis of the problems to be solved, the parameters involved, and the elaborate computer programs developed to perform the calculations. This book bridges the gap between nuclear reactor theory and the implementation of that theory, including the problems to be encountered and the level of confidence that should be given to the methods described. Volume III: Control Rods and Burnable Absorber Calculations. Perturbation Theory for Nuclear Reactor Analysis. Thermal Reactors Calculations. Fast Reactor Calculations. Seed-Blanket Reactors. Index.
The results for development of methods and computer programs for integrated optimization of parameters of perspective fast reactors are given. The possibilities of the program for the reactor campaign calculation are analysed. This program is based on utilisation of the Bubnov-Galerkin method and Wigner disturbance theory. The possibility of application of approximation methods for the optimization researches is discussed. The results of development of the programs for complex reactor computations with account of control rods system and change of physical parameters in the reactor campaign are discussed. (author).
The days of high-temperature reactors in the Federal Republic of Germany are numbered. The AVR has been decommissioned, and an application has been filed for licensing the decommissioning of the THTR. Nevertheless, Prof. Dr. Rudolf Schulten who is the director of Juelich Nuclear Research Center's Institute for Reactor Development, and also full professor of Aachen Technical University in the field of reactor safety, predicts a good future for the HTR reactor line on a worldwide level, due to the inherent safety of this reactor type. (orig.).
In the framework of a global analysis of the various available sources of energy, Japan has reserved a prominent place to the nuclear energy, and in the long-term view, to the breeder reactor which will be due for commercial deployment in 2010. To achieve these objectives, three stages are envisaged, one of the experimental reactor Joyo (in service), one of the demonstration reactor Monju (its construction has been decided), and one of the pre-commercial reactor (due to be taken in hand at the beginning of the Nineties). Efforts will be made in parallel concerning the fuel cycle.
As the U.S. Department of Energy's (DOE's) Solar Energy Technologies Program initiates new cost-shared solar energy R&D under the Solar America Initiative (SAI), it is useful to analyze the experience gained from cost-shared R&D projects that have been funded through the program to date. This report summarizes lessons learned from two DOE-sponsored photovoltaic (PV) projects: the Photovoltaic Manufacturing Technology/PV Manufacturing R&D (PVMaT/PVMR&D) project and the Thin-Film PV Partnership project. During the past 10-15 years, these two projects have invested roughly $330 million of government resources in cost-shared R&D and leveraged another $190 million in private-sector PV R&D investments. Following a description of key findings and brief descriptions of the PVMaT/PVMR&D and Thin-Film PV Partnership projects, this report presents lessons ...
The Neutron Radiography Reactor (NRAD) operated by Argonne National Laboratory is described in this paper. NRAD was designed to allow radiography of highly absorbing reactor fuel assemblies in the vertical position on the routine basis. 7 figs.
Quantities and compositions of non-tritium radioactive waste are estimated for some current conceptual fusion reactor designs, and disposal of large amounts of radioactive waste appears necessary. Although the initial radioactivity of fusion reactor and f...
This study assesses the feasibility of removing the FFTF reactor vessel from its current location in the reactor cavity inside the Containment vessel to a transporter for relocation to a burial pit in the 200 Area.
The device of the present invention improves reactor safety by suppressing lowering of water level in a shroud which surrounds a reactor core, even upon occurrence of rupture of pipelines in an emergency reactor core cooling system in a recycling pump-incorporated type reactor. Namely, an opening of each of cooling systems which forms the emergency reactor core cooling device in a reactor pressure vessel is disposed above the upper end of the reactor core. Further, it also comprises an independent high pressure water injection system, gravitational dropping type water injection system and an automatic depressurization system. With such a constitution, even if rupture of pipelines in the system should be assumed, coolants never flow directly from the shroud which surrounds the reactor core. In addition, there are no ...
THe high-temperature reactor is one of the alternatives for the now predominantly employed water-reactors. In a recently published book designer Rudolf Schulten outlines his concept. In this article the book is reviewed. (author). 1 ref.; 1 fig.
THe high-temperature reactor is one of the alternatives for the now predominantly employed water-reactors. In a recently published book designer Rudolf Schulten outlines his concept. In this article the book is reviewed. (author). 1 ref.; 1 fig.
The commissioning of four CANDU-600 reactors is discussed, with mention of some design features. The four are Point Lepreau, Gentilly-2, Wolsung and Cordoba reactors. The commissioning of Pickering-5 is also mentioned, and so are some events affecting other CANDU reactors.
For light water reactors, loss of coolant is an important point in safety analysis, whereas for gas-cooled reactors the ingress of water into the core region is an incident of safety relevance. The applicability of the computer code system GAMTEREX to pebble beds of spherical high-temperature gas-cooled reactor fuel elements with simulated water ingress is verified by experiment. The measurements were performed at a Siemens-Argonaut reactor, using its ring core as a driver zone for a pebble-bed core in the center of the reactor.
The days of high-temperature reactors in the Federal Republic of Germany are numbered. The AVR has been decommissioned, and an application has been filed for licensing the decommissioning of the THTR. Nevertheless, Prof. Dr. Rudolf Schulten who is the director of Juelich Nuclear Research Center's Institute for Reactor Development, and also full professor of Aachen Technical University in the field of reactor safety, predicts a good future for the HTR reactor line on a worldwide level, due to the inherent safety of this reactor type. (orig.).
Actinides other than the main uranium or plutonium isotopes take a growing part in the different stages of the nuclear cycle. For the French nuclear power program based on the development of light water reactors and fast breeders, many evaluations of the secondary actinides build up are made for the both reactor types using mainly the existing reactor codes. The comparison of these foreseen compositions with experimental results allows to perform some adjustments of the neutronic data. The secondary actinide compositions are given for some typical fuels and their consequences on the nuclear cycle are discussed. An hypothetical burning of these wastes in fast reactors has been studied and the main conclusions are reported.
Division of Remote Handling and Robotics (DRHR) at Bhabha Atomic Research Centre (BARC) has been working on design and development of Reactivity Control Mechanisms for Nuclear Research Reactors (Dhruva, KAMINI and recently Critical Facility of Advanced Heavy Water Reactor (AHWR)) as well as Power Reactors in India (Pressurized Heavy Water Reactors of 220 MWe at Narora and recently India's first 540 MWe PHWR Unit -1 and 2 at Tarapur). This paper gives a brief account of evolution of reactivity control mechanisms for nuclear research and power reactors in India. (author)
Chemical looping combustion is a novel technology that can be used to meet the demand on energy production without CO{sub 2} emission. To improve CO{sub 2} capture efficiency in the process of chemical looping combustion of coal, a prototype configuration for chemical looping combustion of coal is made in this study. It comprises a fast fluidized bed as an air reactor, a cyclone, a spout-fluid bed as a fuel reactor and a loop-seal. The loop-seal connects the spout-fluid bed with the fast fluidized bed and is fluidized by steam to prevent the contamination of the flue gas between the two reactors. The performance of chemical looping combustion of coal is experimentally investigated with a NiO/Al{sub 2}O{sub 3} oxygen carrier in a 1 kW{sub th} prototype. The experimental results show that the configuration can minimize the amount of residual char entering into the air reactor from the fuel ...
Korea Atomic Energy Research Institute (KAERI) has been developing the integral reactor. The reactor head structure assembly (RHSA) is the structure installed over the reactor cover. Due to the characteristics of an integral reactor, there are many instrument cables and power cables coming out from the reactor cover and main components. The RHSA provides an interface location to connect these cables from Architecture Engineer (AE) and System Designer (SD). It also prevents a pipe whip and it prohibits instruments from becoming missiles. In this research, the axiomatic design approach for the RHSA is performed.
Full text: The ITWG was first formed in 1995 for the purpose of fostering international cooperation for combating illicit trafficking of nuclear materials. The initial focus for the ITWG was on the development of nuclear forensics to help answer attribution questions regarding nuclear materials of unknown origin. More recently, the ITWG has also expanded its focus to include detection of nuclear materials during transit. This paper presents some of the key developments by this group and their potential impact for combating nuclear smuggling. The initial focus of the ITWG was to write a status report on international cooperation on nuclear smuggling forensic analysis. This 26-page report summarized previous work on nuclear forensics and gave an initial analysis on prioritizing techniques and methods for forensic analysis regarding source and route attribution. This report was submitted to the G-8 countries, and shortly thereafter, nuclear forensics was endorsed at the Moscow Summit in ...
The saturation of South Korea's at-reactor (AR) spent fuel storage pools will create a necessity for additional spent fuel storage capacity. Because the South Korean government has the plan to increase the number of nuclear power plants from 20 units (end of 2005) to 27 units by 2015, the increase of spent nuclear fuel generation will be accelerated. Because there is no clear national plan for spent nuclear fuel storage and disposal, the utility company (Korea Hydraulic Nuclear Power company) is planning to construct a spent fuel storage facility with 11 000 tHM capacity for Pressurised Water Reactor (PWR). This study is intended to predict the maximum allowable periods when the storage facility will be fully occupied with respect to the already fixed re-racking plan of spent fuel storage pools and construction of new nuclear power plants. The result from this study will be used as fundamental data for an efficient management of the spent fuel ...
Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our ...
A system model for transmission of computer user's data with a finite number of regular users in a resource-sharing mode in parallel distributed information-processing systems is considered. The mini/microcomputer included in the system model is considered to be receiving the mixed arrival data of the user from a picture-phone terminal with uniformly-distributed data arrivals and a teletypewriter terminal with Erlang-distributed data arrivals. The large-memory performance of the mini/microcomputer is analysed with the mixed input data, constant service-times, synchronous transmission and single server interruption through a first-order Markov process. A simple and general approach to calculate the data arrivals from picture-phone and teletypewriter terminals and their mixed data arrivals is presented. Expressions for memory content probability and average queueing delay are derived. The application of the model is illustrated by presenting an integrated ...
The present paper describes the investigation of the static and dynamic behaviour of an 20 kW pressure electrolyser. The suitability for a coupled operating regime with a wind power plant has been investigated. At first the static behaviour has been analysed. The share of oxygen in hydrogen gas is lower than 0.5 Vol%. But reaching the temperature limit of 80 deg C leads to a switch off of the electrolyser, accompanied by an increase of the oxygen share in hydrogen gas up to 1.3 Vol%. Therefore, an improvement of the cooling system is necessary. Secondly, the electrolyser was excited by different step signals for load changing and finally, the electrolyser has been controlled by the power output signal of the windmill. The investigation shows that the development of a direct coupled wind-hydrogen system will be only a small step. 3 refs.
The Seventh Meeting of the Conference of the Parties (2004) of the Convention on Biological Diversity established a mandate for the negotiation of an international regime on Access to Genetic Resources and Benefit Sharing arising from their utilization. Negotiations have been proceeding and have entered the final phase. Seven working group meetings have been held to date and there is expectation that an instrument will emerge by the final deadline - the Tenth Meeting of the Conference of the Parties in Nagoya, Japan in October 2010. A key component singled out for inclusion in the international regime relates to the recognition and protection of the rights of indigenous and local communities (ILCs) over their traditional knowledge (TK) associated with genetic resources. The Ninth Meeting o...
The authors have cloned and determined the entire nucleotide sequence of cDNAs corresponding to the putative {alpha} subunits of the human and rat mast cell high-affinity IgE receptors. Both human and rat cDNAs encode an NH{sub 2}-terminal signal peptide, two immunoglobulin-like extracellular domains (encoded by discrete exons), a hydrophobic transmembrane region, and a positively charged cytoplasmic tail. The human and rat {alpha} subunits share an overall homology with one another and the immunoglobulin gene family, suggesting that they arose from a common ancestral gene and continue to share structural homology with their ligands. In addition, the rat gene is transcribed into at least three distinct forms, each of which yields a somewhat different coding sequence.
The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.
Baxter (Australas J Philos 79:449?464, 2001) proposes an ingenious solution to the problem of instantiation based on his theory of cross-count identity. His idea is that where a particular instantiates a universal it shares an aspect with that universal. Both the particular and the universal are numerically identical with the shared aspect in different counts. Although Baxter does not say exactly what a count is, it appears that he takes ways of counting as mysterious primitives against which different numerical identities are defined. In contrast, I defend the idea?suggested, though not quite endorsed, by Baxter himself?that counts are independent dimensions of numerical identity. Different ways of counting are explained by the existence of these different sorts of identity (i.e., counts)...
In this paper, we present a very important primitive called Information Checking Protocol (ICP) which plays an important role in constructing statistical Verifiable Secret Sharing (VSS) and Weak Secret Sharing (WSS) protocols. Informally, ICP is a tool for authenticating messages in the presence of computationally unbounded corrupted parties. Here we extend the basic bare-bone definition of ICP, introduced by Rabin et al. and then present an ICP that attains the best communication complexity and round complexity among all the existing ICPs in the literature. We also show that our ICP satisfies several interesting properties such as linearity property which is an important requirement in many applications of ICP. Though not presented in this paper, we can design communication and round efficient statistical (i.e involves negligible error probability in computation) VSS and Multiparty Computation (MPC) protocol using our new ICP.
This paper uses selection criteria from various models in a bounds testing approach to cointegration to estimate the price and income elasticities of demand for total petroleum products (gasoline and diesel) and gasoline share in total products in Indonesia. The results suggest that both total products and gasoline share estimates are more responsive to changes in income than changes in the real price of petroleum products. These results have important policy implications as they suggest that policy makers may need to use market-based pricing policies and other policies such as public enlightenment in addition to regulations like minimum energy efficiency standards to promote efficiency and conservation and curb the rising consumption of petroleum products in Indonesia. (author)
In this paper Particle Bed Reactor (PBR) designs are discussed which use /sup 233/U and /sup 242m/Am as fissile materials. A constant total power of 100MW is assumed for all reactors in this study. Three broad aspects of these reactors is discussed. First, possible reactor designs are developed, second physics calculations are outlined and discussed and third mass estimates of the various candidates reactors are made. It is concluded that reactors with a specific mass of 1 kg/MW can be envisioned of /sup 233/U is used and approximately a quarter of this value can be achieved if /sup 242m/Am is used. If this power level is increased by increasing the power density lower specific mass values are achievable. The limit will be determined by uncertainties in the thermal-hydraulic analysis. 5 refs., 5 figs., 6 tabs.
Four low activation alloy classes, two austenitic and two ferritic, have been incorporated into the MOTA-1B experiment in the FFTF reactor to provide an early assessment of the suitability of such alloys for reactor service.
The FFTF reactor is described. Procedures and equipment used to protect personnel from potential hazards of oxygen deficient environments are described.
The location of defective LMFBR fuel pins by the determination of gas tag isotopic ratios is discussed. The application of this method to the FFTF Reactor briefly described.
This document is the annual update of the FFTF and Advanced Reactors Transition Program Resource Loaded Schedule for FY 2002 using current project direction and authorized funding levels
Of some interest is the comparison between the actinide nuclide burning up (fission) rates such as americium 241, americium 242, curium 244, and neptunium 237, in the reactors with fast or thermal neutron spectra.
Of some interest is the comparison between the actinide nuclide burning up (fission) rates such as americium 241, americium 242, curium 244, and neptunium 237, in the reactors with fast or thermal neutron spectra.
This article gives an account of the recent development of light water reactors new concepts in the world. Different projects are being studied. The CE80+ from Combustion Engineering (CE) is a 1350 MWe-PWR-type reactor whose primary circuit is confined in a spherical metallic containment. This reactor was certified by NRC (national regulatory commission) in mid-1996. The APWR (advanced pressurized water reactor) is developed by MHI (Mitsubishi heavy industries) in a collaboration with Westinghouse, this PWR-type reactor fitted with 4 loops derived from the SP90 model that was developed by Westinghouse during the eighties. 2 units of ABWR (advanced boiling water reactor) were commissioned in Japan in 1996 and 1997, ABWR was certified by NRC in mid-1996. The BWR90+ is developed by ABB-atom (Sweden) and it represents a cautious advanced version of the BWR75. ...
Epulopiscium sp. type B is an enormous intestinal symbiont of the surgeonfish Naso tonganus. Intracellular offspring production in Epulopiscium shares features with endospore formation. Here, we characterize the spoIIE homolog in Epulopiscium. The timing of spoIIE gene expression and presence of interacting partners suggest that the activation of ?(F) occurs early in Epulopiscium offspring development. PMID:21398534
Nuclear knowledge is the basis for almost all nuclear activities, and education and training are the most fundamental means to transfer knowledge from one generation to the next. Understanding means and trends in knowledge transfer through education and training thus deserves a closer examination. In the past years, a number of trends and questions in nuclear knowledge, education and training have emerged. With declining student enrolment numbers and a general stagnation of the use of nuclear power in some of the IAEA's Member States, the issue of a slow erosion of the knowledge base and the possibility of loosing knowledge has become increasingly important, in particular if seen against the background of a possible renaissance of nuclear power in the future. In other Member States, an expansion of nuclear power is expected, with a corresponding need for human resources. As a result, in many Member States education and training of the next generation and succession planning have become ...
In higher plants, three subfamilies of sucrose nonfermenting-1 (Snf1)-related protein kinases have evolved. While the Snf1-related protein kinase 1 (SnRK1) subfamily has been shown to share pivotal...Full Text Available
A new iron phosphate (NH4)4Fe3(OH)2F2[H3(PO4)4] has been synthesized hydrothermally at HF concentrations from 0.5 to 1.2 mL. Single-crystal X-ray diffraction analysis reveals its three-dimensional open-framework structure (monoclinic, space group P21/n (No. 14), a=6.2614(13) A, b=9.844(2) A, c=14.271(3) A, ?=92.11(1)o, V=879.0(3) A3). This structure is built from isolated linear trimers of corner-sharing Fe(III) octahedra, which are linked by (PO4) groups to form ten-membered-ring channels along [1 0 0]. This isolated, linear trimer of corner-sharing Fe(III) octahedra, [(FeO4)3(OH)2F2], is new and adds to the diverse linkages of Fe polyhedra as secondary building units in iron phosphates. The trivalent iron at octahedral sites for the title compound has been confirmed by synchrotron Fe K-edge XANES spectra and magnetic measurements. Magnetic measurements also show that this compound exhibit a strong antiferromagnetic exchange below TN=17 K, ...
The new collaborative exploitation of the JET Facilities requires suitable technical tools and infrastructure measures to enable the Remote Participation of scientists from all European Fusion labs. Such measures are being gradually introduced. They comprise of a toolkit for Remote Data Access, Remote Computer Access and for teleconferencing, and of infrastructure measures that address network connectivity, network security, shared documentation and technical support.
HIX, a recombinant derived from Moloney leukemia virus, has an envelope glycoprotein different from that of the Moloney virus. HIX and Moloney viruses share the majority of the large T1 oligonucleotides...Full Text Available
The yeast phosphatidylinositol transfer protein (Sec14p) is required for biogenesis of Golgi-derived transport vesicles and cell viability, and this essential Sec14p requirement is abrogated by inactivation...Full Text Available
We conducted a genome-wide association study of gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC) in ethnic Chinese subjects in which we genotyped 551,152 single nucleotide polymorphisms...Full Text Available
Genome-wide association studies (GWAS) have identified more than 2,000 trait-SNP associations, and the number continues to increase. GWAS have focused on traits with potential consequences for human...Full Text Available
We report the first experimental generation and characterization of a six-photon Dicke state and demonstrate its remarkable versatility by projecting out four- and five-photon Dicke states, in addition to four-photon GHZ- and W-states. These multipartite states are studied by developing experimentally favorable characterization tools. Furthermore, we show that Dicke states have interesting applications in multiparty quantum networking protocols such as open-destination teleportation, telecloning and quantum secret sharing.
We propose a scheme able to generate stationary continuous variable entanglement between an optical and a microwave cavity mode by means of their common interaction with a micro-mechanical resonator. We show that when both cavities are intensely driven one can generate bipartite entanglement between any pair of the tripartite system, and that, due to entanglement sharing, optical-microwave entanglement is efficiently generated at the expense of microwave-mechanical and opto-mechanical entanglement.
Using the Philips DRM distributed real-time multiprocessing system, designers can implement high-performance computer systems using VME hardware and the C programming language. The system provides a virtual-processing environment in which several 68000 CPUs share the workload. There are no centralized components, and tasks can be assumed by the rest of a system in the event of an individual processor's failure.
It is shown that recuperator in which the thermal energy of particles is transformed into electric oue under drift in crossed fields is naturally coupled with dragontype magnetic confinement system, so the recuperation process can be initiated in the dragon magnetic field. A number of questions occuring under analysis of recuperator-dragon system is considered, including the dynamics of particle transfer to the recuperator, the share of particles entering the recuperator, the effect of rotational transform and the recuperation efficiency.
Cystic fibrosis (CF) is a monogenic disease characterized by a high variability of disease severity and outcome that points to the role of environmental factors and modulating genes that shape the course...Full Text Available
The US Department of Energy, Office of Technical and Financial Assistance (OTFA) promotes the application of renewable energy and energy efficiency technologies and practices by working cooperatively with state and local governments and private and nonprofit organizations, providing technical and financial assistance and serving as network for sharing information. This report is an overview of some of the programs designed to aid in solving our national energy problems.
Discussion is presented of world CO{sub 2} emissions and the effect rising population and population distribution has on this. Possible ways of decreasing emissions are presented, including potential for heat recovery, exhaust-air purification as an energy supply, shared power supply in industry, the use of cogeneration, and multiple use of heat in industry. 9 refs., 10 figs., 3 tabs.
The development and experimental demonstration of a high-temperature seal for the SHARE ceramic dome cavity receiver is reported. The mechanical contact seal which was tested on one-foot-diameter silicon-carbide ceramic-dome hardware at pressure differentials to four atmospheres and dome temperatures to 2200/sup 0/F (1200/sup 0/C) showed negligible leakage at expected receiver operating conditions. Potential solar receiver applications for the technology are illustrated.
Increasingly, utility organizations recognize the value of sharing data and applications among their computing environments. A typical utility`s computing environment may consist of disparate computer platforms. The focus of this paper is to highlight importance of a documented information technology architecture for identifying business perspectives for interoperability, and to brief utility management about the Electric Power Research Institute`s (EPRI) accomplishment along these same lines.
BackgroundTrisomic variants of human embryonic stem cells (hESCs) arise spontaneously in culture. Although trisomic hESCs share many properties with diploid hESCs, they also exhibit...Full Text Available
A series of translocation break points found in a subset of human acute leukemias have one of the breaks on human chromosome 11q23. This region has recently been cloned and a large gene, ALL-1, with...Full Text Available
This program is designed in order to calculate electricity generation cost by different energy sources, and menu type is adopted for user convenience. This program also graphically shows the share of capital investment cost, O and M cost, and fuel cost. Sensitivity analysis about discount rate can also be carried out by this program, taking into consideration the important role of the discount rate in the generation costs calculation. (Author) 7 refs., 1 fig., 3 tabs.
The invention concerns a procedure for operating reactors in nuclear power plants. It aims at utilizing power reserves in nuclear power plants. This can be achieved by a steam-side connection of the steam generators of two reactors. The amount of steam exchanged between the units is chosen in such a way that power changes at the steam turbines feedback mainly to the corresponding reactor. In order to realize a high power transfer it is necessary to return the amount of condensate produced in the steam receiving unit and corresponding to the power transferred to the feedwater system of the steam donating unit.
The purpose of this paper is to describe instrumentation and control (I C) system improvements at Experimental Breeder Reactor 11 (EBR-11). The improvements are focused on three objectives; to keep the reactor and balance of plant (BOP) I C systems at a high level of reliability, to provide diagnostic systems that can provide accurate information needed for analysis of fuel performance, and to provide systems that will be prototypic of I C systems of the next generation of liquid metal reactor (LMR) plants.
The purpose of this paper is to describe instrumentation and control (I&C) system improvements at Experimental Breeder Reactor 11 (EBR-11). The improvements are focused on three objectives; to keep the reactor and balance of plant (BOP) I&C systems at a high level of reliability, to provide diagnostic systems that can provide accurate information needed for analysis of fuel performance, and to provide systems that will be prototypic of I&C systems of the next generation of liquid metal reactor (LMR) plants.
Results of tests on the 1 kg/h continuous reactor for the hydroliquefaction of coal are described. The reactor was operated at 415-435 C and 21 MPa using a continuous stirred reactor with a retention time of about 2 hours. All product oils were recovered by distillation. Sub-bituminous coal was found to give the best product yield. Tests using 5% red mud and 3% improved red mud showed significant increases in oil yield. (4 refs.)
A new reactor concept is described which would enable fission fragments to be continuously extracted from the reactor. Such a reactor has the potential of enabling extremely energetic and ambitious deep space missions. In this talk the basic physics issues involved in the operation of this type of reactor are outlined, and some possible applications to space exploration are described. 3 refs., 2 figs., 3 tabs.
The kinetic parameters, ..cap alpha.. the coupling coefficient and tau-bar the mean neutron transit time have been determined using a reactor oscillator on the coupled-core of the Queen Mary College research reactor. By using correlation techniques it has proved possible to use detectors small enough to be inserted in the fuel tanks. It is shown that the simplified Baldwin model with one-group diffusion theory is inadequate to describe the kinetic behaviour and the experimentally-determined parameters are dependent upon the positioning of the detectors.
An experimental plan for improving the problems of failed fuel location system in Wolsung Unit-2 reactors was established. It is not possible to make an experiment on the failed fuel monitoring nuclides in the cold laboratories because they have very short half life. Therefore, the experiments can be only carried out at the existing monitoring system under reactor operation. For that reason, an experimental plan was drawn up for installing the radiation detection system on reactor site.
Dr. Rudolf Schulten of West Germany and expert witnesses from national laboratories, utilities, and the nuclear industry testified on reactor safety issues as they relate to the Chernobyl accident and public concern that modern technology has not paid enough attention to public safety. Each of the witnesses contributed safety-related information based on what has been learned from the Soviet incident. Particular focus went to similarities and differences between the Chernobyl and US reactors in safety design and engineering and to the environmental effects of the accident. The N reactor near Richland and a commercial reactor at Fort St. Vrain, Colorado are the only two operating graphite reactors, but neither is a boiling water reactor.
Dr. Rudolf Schulten of West Germany and expert witnesses from national laboratories, utilities, and the nuclear industry testified on reactor safety issues as they relate to the Chernobyl accident and public concern that modern technology has not paid enough attention to public safety. Each of the witnesses contributed safety-related information based on what has been learned from the Soviet incident. Particular focus went to similarities and differences between the Chernobyl and US reactors in safety design and engineering and to the environmental effects of the accident. The N reactor near Richland and a commercial reactor at Fort St. Vrain, Colorado are the only two operating graphite reactors, but neither is a boiling water reactor.
Since the first round of conceptual fusion reactor designs in 1973 - 1974, there has been considerable progress in design improvement. Two recent tokamak designs of the Wisconsin and Culham groups, with increased plasma beta and wall loading (power density), lead to more compact reactors with easier maintenance. The Reference Theta-Pinch Reactor has undergone considerable upgrading in the design of the first wall insulator and blanket. In addition, a conceptual homopolar energy storage and transfer system has been designed. In the case of the mirror reactor, there are design changes toward improved modular construction and ease of handling, as well as improved direct converters. Conceptual designs of toroidal-multiple-mirror, liner-compression, and reverse-field pinch reactors are also discussed. A design is presented of a toroidal multiple-mirror reactor that ...
This paper presents the results of a series of experiments performed to study the effect of initial pressure vessel conditions on the extent of melt dispersal from scaled reactor cavities and describes progress in development of a mathematical model which is designed to predict the melt mass dispersed from reactor cavities as a function of reactor vessel initial conditions and on the vessel breach area. The model, which is being developed to also characterize the heat transfer and chemical reaction phenomena which would take place within the reactor cavity, is designed to be incorporated into a lumped-parameter containment analysis computer code.
The invention concerns an integrated nuclear reactor comprising natural convection cooling of the supporting skirt on which rests the shield closing the reactor vessel. Cooling is achieved by making the air circulate from the bottom to the top around the skirt and removing this air by a stack. The air can be atmospheric air or air taken from the low parts of the reactor. In the latter case, the stack emerges near a metal roof releasing its heat to the atmosphere by radiation, the air then dropping to the low parts. Application to fast nuclear reactors.
This paper discusses the remote plugging of leaks in inaccessible pipework, with main reference to small leaks which frequently appear in ancillary cooling water circuits of nuclear reactors. Initially developed to cure problems of the pre-stressed concrete pressure vessels of UK reactors, the ZORIC sealant has been used to repair leaking biological shield pipework on six CANDU reactors. ZORIC is based on a water-soluble epoxy resin and an aqueous suspension of a refined mineral clay. This paper describes the evolution of the sealant, the qualification and testing program, and their application to CANDU reactor systems. 2 refs., 6 figs.
The most important and difficult part of materials research for fusion reactor is realized to be irradiation studies of fusion reactor materials. Irradiation studies of fusion reactor materials utilizing FFTF/MOTA, as one of Japan/U.S.A. Fusion Collaboration Programs, have important role to establish fundamental understanding of heavy irradiation effects on materials behavior and properties and to develop methods and technologies for advanced irradiation studies under fusion reactor environment. This paper briefly reviews the history, the state of the art, and the future of the FFTF/MOTA program. (author).
RELAP5 (Reactor Excursion and Leak Analysis Program) is a system code developed at the Idaho National Environmental and Engineering Laboratory for thermal hydraulic analysis of nuclear reactors. The code RELAP5 is widely used for safety analysis studies of commercial nuclear power plants. However, recent released version of RELAP5/3.2 and over present significant capabilities for analysis of nuclear reactor research systems. As a contribution to the assessment of RELAP5/3.3 for research reactor safety analysis, experimental data from the University of Massachusetts Lowell Research Reactor UMLRR are used. The UMLRR is a 1 MW, light water moderated and cooled, graphite-reflected, open-pool type research reactor. This paper presents the development and the validation of a UMLRR-RELAP model using experimental data. For this purpose, a series of experiments were ...
The United State Domestic Research Reactor Infrastructure Program at the Idaho National Laboratory manages and provides project management, technical, quality engineering, quality inspection and nuclear material support for the United States Department of Energy sponsored University Reactor Fuels Program. This program provides fresh, unirradiated nuclear fuel to Domestic University Research Reactor Facilities and is responsible for the return of the DOE-owned, irradiated nuclear fuel over the life of the program. This presentation will introduce the program management team, the universities supported by the program, the status of the program and focus on the return process of irradiated nuclear fuel for long term storage at DOE managed receipt facilities. It will include lessons learned from research reactor facilities that have successfully shipped spent fuel elements to DOE receipt facilities.
The operation of a nuclear power reactor necessarily implies the consumption or burnup of reactor fuel by fission and capture, which gives rise to a decrease in the reactivity of the reactor. The effect of americium formation on the criticality of a thermal power reactor using two types of fuel is studied. The three-dimensional core calculation is used to calculate the production of the transuranium isotopes and their effect on the effective multiplication factor (K[sub eff]). This effect cannot be neglected for thermal power reactors with UO[sub 2]-PuO[sub 2] fuel (3.11% after 70 weeks of operation). The effect of the transuranium isotopes on the K[sub eff] for a thermal power reactor with UO[sub 2] fuel is about 0.0018% and can be ignored. (author).
The operation of a nuclear power reactor necessarily implies the consumption or burnup of reactor fuel by fission and capture, which gives rise to a decrease in the reactivity of the reactor. The effect of americium formation on the criticality of a thermal power reactor using two types of fuel is studied. The three-dimensional core calculation is used to calculate the production of the transuranium isotopes and their effect on the effective multiplication factor (K_e_f_f). This effect cannot be neglected for thermal power reactors with UO_2-PuO_2 fuel (3.11% after 70 weeks of operation). The effect of the transuranium isotopes on the K_e_f_f for a thermal power reactor with UO_2 fuel is about 0.0018% and can be ignored. (author).
In allusion to the explosion of a urea reactor took place in a fertilizer plant at Pingyin, Shandong, China, a series of evidence collection and inspection jobs which includes collecting operation condition and parameters, sampling the explosion fracture, reactor body apart from explosion fracture, and leak detection medium and its hangover, etc., had been carried out firstly. Based on these jobs, farther analysis and computation work has been done to the structural and materials characteristics and the operation condition of the urea reactor, including compositions, metallographic phases, tensile properties, impact energy, strain ageing characteristics, and fracture toughness of the urea reactor steels, the compositions of leak detection medium and its hangover in the urea reactor, and ex...
High-flux neutron sources are continuing to be of interest both in Canada and internationally to support materials testing for advanced power reactors, new developments in extracted-neutron-beam applications, and commercial production of selected radioisotopes. The advanced MAPLE reactor concept has been developed to meet these needs. The advanced MAPLE reactor is a new tank-type D_2O reactor that uses rodded low-enrichment uranium fuel in a compact annular core to generate peak thermal-neutron fluxes of 1 x 10"1"9 n#centre dot#s"-"1 in a central irradiation rig with a thermal power output of 50 MW. Capital and incremental development costs are minimized by using MAPLE reactor technology to the greatest extent practicable.
The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are unusually rapid.
The testing of candidate fuel elements at prototypic operating conditions with respect to temperature, power density, hydrogen coolant flow rate, etc., a crucial component in the development and qualification of nuclear rocket engines based on the Particle Bed Reactor (PBR), NERVA-derivative, and other concepts. Such testing may be performed at existing reactors, or at new facilities. A scoping study has been performed to assess the feasibility of testing PBR based fuel elements at the TREAT reactor. initial results suggest that full-scale PBR, elements could be tested at an average energy deposition of {approximately}60--80 MW-s/L in the current TREAT reactor. If the TREAT reactor was upgraded to include fuel elements with a higher temperature limit, average energy deposition of {approximately}100 MW/L may be achievable.
SCDAP/RELAP5 code has been developed in US for best-estimate simulation of light water reactors transients during nuclear accidents. The code models the coupled behaviour of the cooling system, reactor core and fission products release during the accident. It is the result of the coupling between RELAP5, modelling thermal hydraulic, control system, reactor kinetics and the transport of noncondensable gases, and SCDAP code modelling the behaviour of the reactor core during severe accidents. The paper briefly presents the application of SCDAP/RELAP5 code to CANDU severe accident analysis. Also, the paper proposes a summary of the needs for development that could enhance the quality of the severe accidents related predictions in CANDU reactors. (authors)
The objective of the study is to improve the volume of nuclear power plant which adopts passive safety system concept. The passive safety system reactor is characterized by excellent safety and reliability. But the volume of NSSS (Nuclear Steam Supply System) of the passive safety system reactor is so small that it should be upgraded for commercial operation. For volume upgrade, detailed analyses are performed as follows; core design, hydraulics, design and mechnical structures, and safety analysis. In addition to above analysis, some investigations must be supplied as follows: power density vs. DNB margin decrease, outlet temperature vs. EPRI-URD, additional tests for upgraded reactor, dynamic analysis of mechanical vibration according to expanded reactor vessel and expanded in-core structures, and Merit loss of passive safety system reactor according to design margin decrease. ...
The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only material out of reactor at least one year is considered. The total activity in Ci/W(th) of the Starfire tokamak is slightly greater than that of the PWR during the active lifetimes of the two reactors and beyond 1000 years. However, using reduced activation materials in Starfire can result in about 1/2000 as much long-lived radioactivity as in the fission reactor. It is stressed that comparison of wastes on this basis is not straightforward, since the radioisotopes and methods required for their disposal are different for fusion and fission reactors. 2 refs., 1 fig., 2 tabs.
Today TBP and TBAs are the compounds which have the highest potential to replace the hydrides arsine and phosphine in the MOVPE process. The authors have demonstrated the entire material system Ga-In-As-P can be grown without any loss of quality using TBP and TBAs not only in one reactor, but in a complete family of reactors. These reactors range from small-scale single wafer R and D reactors to multiwafer Planetary Reactor systems. Both InP based and GaAs based materials could be grown with an excellent quality. Thus all growth processes for III-V devices--long and short wavelength lasers, LEDs, high speed transistors, etc.--can be switched to TBP and TBAs. This will drastically reduce safety hazards and lead to processes that have advantages both from the ecological and economical point of view.
Two sodium cooled reactors are currently being operated in the United States of America for the US Department of Energy. These are Experimental Breeder Reactor 11, EBR-11, and the Fast Flux Test Facility, FFTF. EBR-11 is located near Idaho Falls, Idaho, and the FFTF is near Richland, Washington. These reactors are currently engaged in a wide range of testing including fuels and materials tests, and plant system performance and safety development. The US DOE program also includes designs of a next generation sodium cooled power reactor. The FFTF and EBR-11 communities are providing input to these designs. This paper discusses the efforts to develop and operate cover gas systems for the sodium cooled nuclear reactor program in the USA.
Encapsulation of a unique isotopic blend of krypton and xenon gas employs a special application of laser technology. The encapsulated gas is then used as the primary medium for detection and identification of failed nuclear fuel rods. The use of gas tagging as a means of detecting and identifying failed nuclear fuel rods has been successfully demonstrated and used by the Argonne National Laboratory, Experimental Breeder Reactor (EBR-2) Project, and the Westinghouse Hanford Company (WHC), Fast Flux Test Facility (FFTF) Fast Breeder Reactor Program. The Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan has selected this leak detection system for use in their MONJU Prototype Reactor fuel assemblies. The MONJU reactor is almost identical in design to the highly successful FFTF reactor, which is currently in standby status.
The Fast Flux Test Facility (FFTF) is a 400 Mw(t), loop-type, sodium-cooled, fast neutron reactor. It is operated by the Westinghouse Hanford Company for the United States Department of Energy at Richland, Washington. The FFTF is a multipurpose test reactor used to irradiate fuels and materials for programs such as Liquid Metal Reactor (LMR) research, fusion research, space power systems, isotope production and international research. FFTF is also used for testing concepts to be used in Advanced Reactors which will be designed to maximize passive safety features and not require complex shutdown systems to assure safe shutdown and heat removal. The FFTF also provides experience in the operation and maintenance of a reactor having prototypic components and systems typical of large LMR (LMFBR) power plants. The 5 year operational performance of the FFTF reactor is ...
The Fast Flux Test Facility (FFTF) is a 400 Mw(t), loop-type, sodium-cooled, fast neutron reactor. It is operated by the Westinghouse Hanford Company for the United States Department of Energy at Richland, Washington. The FFTF is a multipurpose test reactor used to irradiate fuels and materials for programs such as Liquid Metal Reactor (LMR) research, fusion research, space power systems, isotope production and international research. FFTF is also used for testing concepts to be used in Advanced Reactors which will be designed to maximize passive safety features and not require complex shutdown systems to assure safe shutdown and heat removal. The FFTF also provides experience in the operation and maintenance of a reactor having prototypic components and systems typical of large LMR (LMFBR) power plants. The 5 year operational performance of the FFTF reactor is ...
The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment ...
The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects are calculated, with reference to ITER/NET (International Thermonuclear Experiment ...
In this paper, we describe our vectorized and parallelized adaptive mesh refinement (AMR) N-body code with shared time steps, and report its performance on a Fujitsu VPP5000 vector-parallel supercomputer. Our AMR N-body code puts hierarchical meshes recursively where higher resolution is required and the time step of all particles are the same. The parts which are the most difficult to vectorize are loops that access the mesh data and particle data. We vectorized such parts by changing the loop structure, so that the innermost loop steps through the cells instead of the particles in each cell, in other words, by changing the loop order from the depth-first order to the breadth-first order. Mass assignment is also vectorizable using this loop order exchange and splitting the loop into $2^{N_{dim}}$ loops, if the cloud-in-cell scheme is adopted. Here, $N_{dim}$ is the number of dimension. These vectorization schemes which eliminate the unvectorized loops are ...
This study uses a multi-part, split-sample contingent valuation method (CVM) and fair share (FS) survey to better understand the public's valuation of mitigating global climate change through its willingness to pay for biomass or 'cellulosic' ethanol. In addition to a basic CVM question, a related scenario was developed that asked half of the survey respondents to state their fair share cost to lessen a potential food shortage in the next decade, also through the expanded use of cellulosic ethanol. Three alternative biomass feedstocks were assessed: farming residues, forestry residues and paper mill wastes, and municipal solid wastes. Overall a slightly larger proportion of respondents were WTP extra for cellulosic ethanol in the basic CVM scenario than in the FS scenario, though no significant differences were found in the WTP for the different feedstocks. Bid curve lognormal regression results for the two models ...
This paper presents an uplink capacity analysis and interference avoidance technique for a femtocell based two-tier DS-CDMA network using shared spectrum. Assuming randomly distributed macrocell users and femtocell base stations (BS), we evaluate a network-wide area spectral efficiency metric called the operating contour (OC) defined as the feasible combinations of the average macrocell users and femtocell BS per cell-site that meet a target outage constraint $\\epsilon$. A contribution of this work is an accurate characterization of the uplink outage probability taking cross-tier power control, path-loss and shadowing effects into account. We show that a time-hopped CDMA physical layer coupled with sectorized receive antennas shows dramatic performance improvements in both light and heavily loaded two-tier networks, relative to a split spectrum two-tier network with omnidirectional femtocell antennas. These results provide insights into design of robust ...
This paper highlights some of the conceptual and methodological problems involved in the compilation of statistics on economic aid to developing countries. Figures from the OECD Development Assistance Committee (DAC) and the Organization of Petroleum Exporting Countries (OPEC) member states are compared to point up problems in the interpretation of the statistics. One area of concern is the listing of funds provided by financial institutions located in the DAC countries. OPEC capital often forms a majority of such institutions; yet the figures do not measure the OPEC share of the capital nor its share of the risk borne in its provision of the loans. Another area of concern is bond purchases and subscriptions to syndicated loans by OPEC financial institutions in the financial markets of DAC countries. The flows in these instances, originating from OPEC sources, are merely channeled through the DAC financial markets. Based on origin and risk ...
Several nuclear power plant sites have been wounded in the crossfire between two distinct corporate cultures. The traditional utility culture lies on one side and that of the nuclear navy on the other. The two corporate cultures lead to different perceptions of open-quotes safety culture.close quotes This clash of safety cultures obscures a very important point about nuclear plant operations: Safety depends on organizational learning. Organizational learning provides the foundation for a perception of safety culture that transcends the conflict between utility and nuclear navy cultures. Corporate culture may be defined as the knowledge, attitudes, and beliefs shared by employees of a given company. Safety culture is the part of corporate culture concerning shared attitudes and beliefs affecting individual or public safety. If the safety culture promotes behaviors that lead to greater safety, employees will tend to open-quotes do the right ...
This paper examines the global impacts of a policy that internalizes the external costs (related to air pollution damage, excluding climate costs) of electricity generation using a combined energy systems and macroeconomic model. Starting point are estimates of the monetary damage costs for SO{sub 2}, NO {sub X} , and PM per kWh electricity generated, taking into account the fuel type, sulfur content, removal technology, generation efficiency, and population density. Internalizing these externalities implies that clean and advanced technologies increase their share in global electricity production. Particularly, advanced coal power plants, natural gas combined cycles, natural gas fuel cells, wind and biomass technologies gain significant market shares at the expense of traditional coal- and gas-fired plants. Global carbon dioxide emissions are lowered by 3% to 5%. Sulfur dioxide emissions drop significantly below the already low level. The ...
This paper examines the global impacts of a policy that internalizes the external costs (related to air pollution damage, excluding climate costs) of electricity generation using a combined energy systems and macroeconomic model. Starting point are estimates of the monetary damage costs for SO{sub 2}, NOX, and PM per kWh electricity generated, taking into account the fuel type, sulfur content, removal technology, generation efficiency, and population density. Internalizing these externalities implies that clean and advanced technologies increase their share in global electricity production. Particularly, advanced coal power plants, natural gas combined cycles, natural gas fuel cells, wind and biomass technologies gain significant market shares at the expense of traditional coal- and gas-fired plants. Global carbon dioxide emissions are lowered by 3% to 5%. Sulfur dioxide emissions drop significantly below the already low level. The policy ...
Estimates of annual rates of change of fuel switching are constructed using logistic curve models fitted to often sparse historical data on fuel use in the USA. The estimated annual rate of loss of market share of an old fuel is then shown to be correlated with five-year averages of declines in the rate of growth of affected vehicle numbers. Other statistical tests show a positive correlation between five-year average changes in the rate of growth of the vehicle numbers and of macroeconomic activity when the affected vehicles are directly responsible for a large share of that activity. The vehicle types shown to have this effect are locomotives from 1885-1915 and automobiles thereafter. The third set of tests supports an interpretation that the indirect effects of fuel switches are significant and consistent with GNP throughout the 1880-1980 period. It is shown that a pronounced drop in GNP growth occurs at the time when the important fuel ...
Heterogeneous base stations (e.g. picocells, microcells, femtocells and distributed antennas) will become increasingly essential for cellular network capacity and coverage. Up until now, little basic research has been done on the fundamentals of managing so much infrastructure -- much of it unplanned -- together with the carefully planned macro-cellular network. Inter-cell coordination is in principle an effective way of ensuring different infrastructure components behave in a way that increases, rather than decreases, the key quality of service (QoS) metrics. The success of such coordination depends heavily on how the overhead is shared, and the rate and delay of the overhead sharing. We develop a novel framework to quantify overhead signaling for inter-cell coordination, which is usually ignored in traditional 1-tier networks, and assumes even more importance in multi-tier heterogeneous cellular networks (HCNs). We derive the overhead quality ...
Project finance is asset-based financing, meaning that the project lenders have recourse only to the underlying assets of a project. It involves both debt and equity, where the debt-to-equity ratio is typically large (e.g., 70% debt to 30% equity). Debt is used when available and when it is the least expensive form of financing, with equity still needed for credit worthiness. Most important, revenue from the project must be able to generate a return to the equity investors, and pay for interest and principal on the debt, transaction costs associated with developing and structuring the project, and operations and maintenance costs. Successful project financing must provide a structure to manage and share risks in an optimal way that benefits all participants, allocating risks to those entities that are able to mitigate each specific risk, and to share information about putting risk management in the proper hands at the proper stage of project ...
High precision, fast computation speed, as well as a good capability of fault tolerant and reconstruction are required more and more for spacecraft attitude determination system. To realize the above requirement, an approach was presented to the synthesis of federated filters using sigma point technique. In this algorithm, the sigma point technique brought the algorithm a high precision, while the federated structure significantly enhanced the filters' capability of multi-rate information fusion, fault tolerance, and system modularity. Within consideration of computation consumption, a simple information-sharing formulation was derived to adapt to the special property of sigma point distribution, and a dynamical information sharing strategy for multi-rate fusion was developed. A numerical simulation example was employed to give the algorithm a test, where the simulated system contained a suit of gyroscopes; a three-axis magnetometer and a sun ...
Shared memory multiprocessors come back to popularity thanks to rapid spreading of commodity multi-core architectures. As ever, shared memory programs are fairly easy to write and quite hard to optimise; providing multi-core programmers with optimising tools and programming frameworks is a nowadays challenge. Few efforts have been done to support effective streaming applications on these architectures. In this paper we introduce FastFlow, a low-level programming framework based on lock-free queues explicitly designed to support high-level languages for streaming applications. We compare FastFlow with state-of-the-art programming frameworks such as Cilk, OpenMP, and Intel TBB. We experimentally demonstrate that FastFlow is always more efficient than all of them in a set of micro-benchmarks and on a real world application; the speedup edge of FastFlow over other solutions might be bold for fine grain tasks, as an example +35% on OpenMP, +226% on ...
The 'high-tension distribution line design support system' was developed for the 'work design support system'. This support system is composed of the work outline editor for preparing work details and facility data and the inference engine for preparing practical design plans, and can check system conditions such as voltage drop and deviation from technical standards automatically. The work outline editor takes charge of selection of work items, selective input of system information, and setting of some conditions such as pole position and reserved load onto a system diagram. The inference engine provides the design plan automatically based on the information inputted by the editor. For the design of high-tension distribution line, such various factors as local condition and load sharing of distribution systems should be considered. This design support system attains efficient processing by not total automation of design works ...
We present a deterministic secure direct communication scheme via entanglement swapping, where a set of ordered maximally entangled three-particle states (GHZ states), initially shared by three spatially separated parties, Alice, Bob and Charlie, functions as a quantum information channel. After ensuring the safety of the quantum channel, Alice and Bob apply a series of local operations on their respective particles according to the tripartite stipulation and the secret message they both want to send to Charlie. By three of Alice, Bob and Charlie's Bell measurement results, Charlie is able to infer the secret messages directly. The secret messages are faithfully transmitted from Alice and Bob to Charlie via initially shared pairs of GHZ states without revealing any information to a potential eavesdropper. Since there is no transmission of the qubits carrying the secret message between any two of them in the public channel, it is completely ...
GAO's review of the H-Coal and Exxon projects showed inadequacies in DOE's contracting practices and a failure by DOE to properly plan, manage, and monitor, especially the H-Coal project. The initial Government-industry H-Coal agreements regarding the level of investment by private sponsors and the ceilings imposed on sharing in cost growth were imbalanced. Larger investments by private sponsors and sharing of cost growth provides an incentive to private sponsors to control costs and helps to assure that each party is fully committed to the success of the project. DOE started the H-Coal project prematurely before sufficiently detailed designs were available and without adequate project planning for functions such as construction scheduling, materials handling, inventory systems, and quality control. DOE staffing was inadequate at both projects to effectively monitor progress and contribute to timely decisions. Its contracts ...
The LHCb Muon detector system is made of several (1368) Multi Wire Proportional Chambers (MWPCs). Those chambers differ in size, readout and constructing materials and are built in various countries: their assembly takes place in different sites and foresee many steps. To ensure the production quality and keep track of panels/chambers production an on-line database has been set up. This web based tool allows an easy sharing of the information: the database update is made possible trough a web interface. The update is easy and reliable. The interface helps the information sharing in different sites and helps optimizing the production rate by allowing feedback on production needs and quality between sites contributing to the production chain. The planning is made using the information on the material availability. Quality tests and crosschecks are made easier, as well as the overall production monitoring. The tool has been developed using mySQL, ...
The purpose of the conversion process is to convert the {sup 233}U fluoride compounds that are being extracted from the Molten Salt Reactor Experiment (MSRE) equipment to a stable oxide for long-term storage at Bldg. 3019.
In order to reduce the air concentration of (sup 3)H in the reactor buiIding of Wolsung Heavy Water Reactor, a computer code for estimation of adsorption behavior was programmed based on an equation derived for analysis of water vapor adsorption, and a ba...
The main aspects of the present WWER-440 reactors spent fuel management are described in the paper. Experimental results of fuel integrity studies which are carried out under conditions of a long-term storage are also presented. (author). 5 refs, 5 figs.
Starting from the Molten Salt Breeder Reactor project of Oak-Ridge, we have performed parametric studies in terms of safety coefficients, reprocessing requirements and breeding capabilities. In the frame of this major re-evaluation of the molten salt reactor (MSR), we have developed a new concept called Molten Salt Fast Reactor or MSFR, based on the Thorium fuel cycle and a fast neutron spectrum. This concept has been selected for further studies by the MSR steering committee of the Generation IV International Forum in 2009. Our reactor's studies of the MSFR concept rely on numerical simulations making use of the MCNP neutron transport code coupled with a code for materials evolution which resolves the Bateman's equations giving the population of each nucleus inside each part of the reactor at each moment. Because of MSR's fundamental characteristics compared to classical ...
This report is the final report on the seismic testing of reactor components conducted since 1977 with opening of the vibration laboratory at KAERI. In 1979, forced vibration testing of Wolsung-1 steam generator model using sine dwell and white nosie rand...
The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only materi...
The paper briefly describes the nuclear reactor facilities at Sandia Laboratories which are used for simulating nuclear weapon produced neutron environments. These reactor facilities are used principally in support of continuing R and D programs for the Department of Energy/Office of Military Application (DOE/OMA) in studying the effects of radiation on nuclear weapon systems and components. As such, the reactors are available to DOE and DOD agencies and their contractors responsible for the radiation hardening of advanced nuclear weapon systems. Emphasis is placed upon two new reactor simulation sources; the Sandia Pulse Reactor-III (SPR-III) Facility which enhances the neutron exposure volume capabilities over those presently available with the existing SPR-II Facility, and the Upgraded Annular Core Pulse Reactor (ACPR) Facility which enhances the neutron ...
Based on a generalized theory of perturbations and on non-linear programming an approach to the quantitative determination of necessary accuracies for nuclear data is described. It is used to calculate transactinide isotope build-up in reactors.
A reactor was proposed in which the breeder mantel would consist of a charge of homogeneous cast breeder elements, so that the breeder element has the same shape as the fuel elements. By this method it would be possible to use the breeder element after its irradiation immediately for the charging of the fuel elements.
The Sp-100 reactor is a lithium-cooled high-temperature fast-spectrum reactor. The fuel is UN. The cladding is fabricated from PWC-11, a Nb alloy, as are all the primary structural components. A reactor lifetime of up to ten years with an operating temperature of 1370 K is required. The accumulated fluence is expected to be 6 x10"2"2 n/cm"2. The damage, which could result in swelling or embrittlement, anneals out as fast as it occurs for the majority of the structure. This has been confirmed by earlier radiation testing. A number of components, however, are exposed to lower temperatures and the reactor design and materials selection for these components must take this into consideration. Radiation effects must also be considered for the UN fuel, bearing materials, etc. To data an instrumented experiment, MOTO 1000A, has been conducted in the FFTF reactor and as uninstrumented ...
The Fast Flux Test Facility (FFTF) reactor, which started operating in 1982, is a 400 MWt sodium-cooled fast neutron reactor located in Hanford, Washington State, and operated by Westinghouse Hanford Co. under contract with U.S. Department of Energy. The reactor has a wide variety of functions for irradiation tests and special tests, and its major purpose is the irradiation of fuel and material for liquid metal reactor, nuclear reactor and space reactor projects. The review first describes major technical specifications and current conditions of the FFTF reactor. Then the plan for irradiation testing is outlined focusing on general features, fuel pin/assembly irradiation tests, and absorber irradiation tests. Assemblies for special tests include the material open test assembly (MOTA), fuel open test assembly (FOTA), closed loop ...
The Fast Flux Test Facility (FFTF) reactor, which started operating in 1982, is a 400 MWt sodium-cooled fast neutron reactor located in Hanford, Washington State, and operated by Westinghouse Hanford Co. under contract with U.S. Department of Energy. The reactor has a wide variety of functions for irradiation tests and special tests, and its major purpose is the irradiation of fuel and material for liquid metal reactor, nuclear reactor and space reactor projects. The review first describes major technical specifications and current conditions of the FFTF reactor. Then the plan for irradiation testing is outlined focusing on general features, fuel pin/assembly irradiation tests, and absorber irradiation tests. Assemblies for special tests include the material open test assembly (MOTA), fuel open test assembly (FOTA), closed loop ...
This is the final Report for the technical ''on-the-job traning'' for the Wolsung CANDU nuclear power plant which is the first Pressurized Heavy Water Reactor setting up in Korea. The technical ''on-the-job traning'' was established to increase the capabi...
Coke consumption may be cut as much as fifty percent using a coal reactor to furnish carbon monoxide for ore reduction in a blast furnace while lowering the sulfur content of pig iron accompanied by a smaller slag volume.
The primary scope of this study is to establish the analysis technology for the advanced reactor designed on the basis of the passive and inherent safety concepts. This study is extended to the application of these technology to the safety analysis of the passive reactor. The study was performed for the small and medium sized reactor and the large sized reactor by focusing on the development of the analysis technology for the passive components. Among the identified concepts the once-through steam generator, the natural circulation of the integral reactor, heat pipe for containment cooling, and hydraulic valve were selected as the high priority items to be developed and the related studies are being performed for these items. For the large sized passive reactor, the study plans to extend the applicability of the best estimate computer code RELAP5/MOD3 which is ...
To propose a new design concept of a nuclear reactor used in the space, research has been conducted on the conceptual design of a new nuclear reactor on the basis of the following three main concepts: (1) Thermionic generation by thermionic fuel elements (TFE), (2) reactivity control by rotary reflector, and (3) reactor cooling by liquid metal. The outcomes of the research are: (1) A calculation algorithm was derived for obtaining convergent conditions by repeating nuclear characteristic calculation and thermal flow characteristic calculation for the space nuclear reactor. (2) Use of this algorithm and the parametric study established that a space nuclear reactor using 97% enriched uranium nitride as the fuel and lithium as the coolant and having a core with a radius of about 25 cm, a height of about 50 cm and a generation efficiency of about 7% can probably be operated continuously ...
The Wind2H2 system is fully functional and continues to gather performance data. In this report, specifications of the Wind2H2 equipment (electrolyzers, compressor, hydrogen storage tanks, and the hydrogen fueled generator) are summarized. System operational experience and lessons learned are discussed. Valuable operational experience is shared through running, testing, daily operations, and troubleshooting the Wind2H2 system and equipment errors are being logged to help evaluate the reliability of the system.
Web portals are nowadays very popular. This type of web sites let users to share information, request advice or help in a particular field, and furthermore allow them to create and extend sites content. Combined with instant messaging systems, used to send messages or files instantaneously to a user or a group of users, and with various kinds of chat programs, which connect two or more individuals simulating a conversation, it is now possible to create "web communities". In this paper we present the opensource tools used to create the "Grid Support Community" of the National Institute for Nuclear Physics in Italy.
Ventilation systems must ensure high room air quality with minimum energy consumption in all states of operation. Systems for ventilation on demand are increasing their market share. (orig./MSK) [Deutsch] Oberste Aufgabe von Raumlufttechnischen Anlagen ist die Sicherstellung guter Raumluftqualitaet bei minimalem Energieverbrauch unter allen Betriebsbedingungen. Um dieses Ziel zu erreichen, setzt sich am Markt zunehmend die bedarfsgeregelte Lueftung durch. (orig./MSK)
Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.
Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein Podolsky Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.
Search engine researchers typically depict search as the solitary activity of an individual searcher. In contrast, results from our critical-incident survey of 150 users on Amazon's Mechanical Turk service suggest that social interactions play an important role throughout the search process. Our main contribution is that we have integrated models from previous work in sensemaking and information seeking behavior to present a canonical social model of user activities before, during, and after search, suggesting where in the search process even implicitly shared information may be valuable to individual searchers.
This study examines the degree of price-integration of equity indices between the major markets of Africa, namely Morocco, Tunisia, Egypt, Kenya, Nigeria, Namibia and South Africa with the European markets of London and Paris. Vector Autoregressive and Autoregressive Distributed Lag methods reveal that African markets are largely price-segmented. The only markets that are price-integrated have shared economic and financial institutions, such as Namibia and South Africa, and Egypt, Tunisia and France. The evidence suggests that development policy should be focussed on enhancing existing institutions rather than embarking prematurely on regional integration.
Convexity/concavity properties of symbol error rates (SER) of the maximum likelihood detector operating in the AWGN channel (non-fading and fading) are studied. Generic conditions are identified under which the SER is a convex/concave function of the SNR. Universal bounds for the SER 1st and 2nd derivatives are obtained, which hold for arbitrary constellations and are tight for some of them. Applications of the results are discussed, which include optimum power allocation in spatial multiplexing systems, optimum power/time sharing to decrease or increase (jamming problem) error rate, and implication for fading channels.
The Schmidt decomposition is an important tool in the study of quantum systems especially for the quantification of the entanglement of pure states. However, the Schmidt decomposition is only unique for bipartite pure states, and {\\it some} multipartite pure states. Here a generalized Schmidt decomposition is given for a class of mixed quantum states. It is shown that it shares some desirable properties with its pure-state counterpart, but lacks some properties which make the pure-state decomposition so important. Experimental methods for the identification of this class of mixed states are provided and some examples are discussed which show the utility of this description.
In this paper, we address the problem of K-out-of-L exclusion, a generalization of the mutual exclusion problem, in which there are $\\ell$ units of a shared resource, and any process can request up to $\\mathtt k$ units ($1\\leq\\mathtt k\\leq\\ell$). We propose the first deterministic self-stabilizing distributed K-out-of-L exclusion protocol in message-passing systems for asynchronous oriented tree networks which assumes bounded local memory for each process.
A quantum secure direct communication scheme using dense coding is proposed. At first, the sender (Alice) prepares four-particle genuine entangled states and shares them with the receiver (Bob) by sending two particles in each entangled state to him. Secondly, Alice encodes secret information by performing the unitary transformations on her particles and transmits them to Bob. Finally, Bob performs the joint measurements on his particles to decode the secret information. The two-step security test guarantees the security of communication.
A simple but powerful inter-process communication machine is presented for programming direct shared memory multiprocessor machines in medium and low level application areas and in particular, for the programming of embedded systems such as intelligent instrumentation and online controllers. The primitives are based on hoare's concept of tightly synchronised data transfer to provide mutual exclusion and synchronisation in a single mechanism. The design of these primitives is discussed with reference to a number of criteria considered appropriate to the application area and their implementation in the Cyba-M multi-microprocessor research is described. 10 references.
In this paper, we proposed a novel quantum secure direct communication scheme with one-time pad in stabilizer formalism. Based on the reuse of qubit sequence, an efficient secure communication of secret messages without first producing a shared secret key can be achieved. One hence may find that the amount of private key needed for quantum communication is smaller than that in the general case. Therefore, the present protocol which is feasible with the present-day techniques may be applied to quantum communication with short-length encoding.
Considerable discussion has taken place during the last decade regarding the role of economic growth in determining environmental quality. Using data from 30 OECD countries for the period 1960-2003 and the nonparametric method of generalized additive models, which enables us to use flexible functional forms, this paper examines the environmental Kuznets curve hypothesis for carbon dioxide (CO2). We find that the reduction of coal share in energy use has a significant effect on CO2. Our results imply that economic growth is not sufficient to decrease CO2 emissions.
Strategic management of key accounts has become an important component of many companies' sales efforts. This research introduces a strategic framework of key account performance that integrates theory from relationship marketing, key account management, and customer equity. Using the three drivers of customer equity - value equity, brand equity, and relationship equity - the framework captures both the relational outcomes (relationship commitment and trust) and financial performance outcomes (profitability and share of spend) of strategic decisions made in key account programs. Implications and future research are then discussed.
Chronic benign pain is commonly associated with chronic fatigue and depression. Depression and chronic fatigue syndrome are also associated with each other and often include pain. Psychologic factors are prominent in these conditions, and they may share neurobiologic factors as well. Management requires separately addressing each component of patients' distress and usually includes physical rehabilitation, education, administration of nonhabituating medications and often counseling. Depression may be a favorable prognostic sign, as it suggests a treatable condition and provides incentive for recovery. PMID:1876618
Data from many measuring devices throughout the Savannah River Site (SRS) is transmitted to a central location for processing as a vital component in the SRS emergency preparedness and response program. The data processing is currently accomplished using VAX-based FORTRAN programs with the data stored in Digital's Record Management System (RMS) files which is shared using global COMMON. A program is underway to store and process this data using a Structured Query Language (SQL)-based Database Management System (DBMS). The advantages of replacing the current system with one using an SQL-based DBMS are discussed.
An ideal introduction to the entire process of setting up a Web site using PHP (a scripting language), MySQL (a database management system), and Apache (a Web server)* Programmers will be up and running in no time, whether they're using Linux or Windows servers* Shows readers step by step how to create several Web sites that share common themes, enabling readers to use these examples in real-world projects* Invaluable reading for even the experienced programmer whose current site has outgrown the traditional static structure and who is looking for a way to upgrade to a more efficient, user-f
This study identifies the environmental conditions under which less CO{sub 2}-emitting and more expensive automobile technology might enter the North American transportation sector. For that purpose, different exogenous CO{sub 2}-reduction targets are imposed and the resulting market shares of hypothetical future automobile technologies calculated. The criteria for the selection of different types of automobiles/fuels is the minimisation of discounted, cumulative transport sector costs over the scenario time horizon. (author) 1 tab., 6 refs.
I formulate a model in which money coexists with equity shares on a risky aggregate endowment. Agents can use equity as a means of payment, so shocks to equity prices translate into aggregate liquidity shocks that disrupt the mechanism of exchange. I characterize a family of optimal monetary policies and find that the resulting equity prices are independent of monetary considerations. I also study a perturbation of the family of optimal policies that targets a positive constant nominal interest rate and find that in this case the real equity return includes a liquidity return that depends on monetary considerations.
The long term objective of the Oil Sands Business Unit of Alberta Energy is to pave the way for Alberta's bitumen production to reach 3 million barrels per day by 2020. This presentation described the national government's role in resource development. It was emphasized that since the Crown is the owner of the oil sands resource, it would benefit by providing strategic leadership and by generating a larger royalty base. The oil sands fiscal regime was described with reference to generic royalty, risk sharing, investment, and project economics. Business rule principles were also outlined along with criteria for project expansions. Both upstream and downstream challenges and opportunities were listed. 4 figs.
The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by the California Energy Commission Public Interest Energy Research program and organized by the National Renewable Energy Laboratory, was held Aug. 24, 2006, in Sacramento, Calif. The workshop provided a forum for industry stakeholders to share their knowledge and experience about technologies, manufacturing approaches, markets, and issues in power electronics for a range of distributed energy resources. It focused on the development of advanced power electronic interfaces for distributed energy applications and included discussions of modular power electronics, component manufacturing, and power electronic applications.
Ubiquitous computing based on small mobile devices using wireless communication links is becoming very attractive. The computational power and storage capacities provided allow the execution of sophisticated applications. Due to the fact that sharing of information is a central problem for distributed applications, the development of self organizing middleware services providing high level interfaces for information managing is essential. ADS is a directory service for mobile ad-hoc networks dealing with local and nearby information as well as providing access to distant information. The approach discussed throughout this paper is based upon the concept of information markets.
To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.
To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.
Comments are made on the Public Inquiry into CEGB's proposal to construct a pressurized water reactor (PWR) at Sizewell, UK. Aspects discussed include: time elapsed and its possible effect on the result; economics of nuclear power plants compared with coal-fired power plants; changes in real sterling/dollar exchange rates; effect of mineworkers' strike; the UK electric power generating system; AGR reactors compared with PWR reactors; extension of Magnox reactor life; radioactive waste management; political decisions.
Utility interest has recently increased in potential future nuclear units that combine the characteristics of smaller size, greater simplicity, and more passive safety features. In response to such interest, General Electric (GE) began development in 1982 of a 600-MW(electric) reactor with simplified power generation and safety systems. This paper provides an overview of the simplified boiling water reactor (SBWR) design, with emphasis on the thermal-hydraulic aspects of the design. The SBWR is a natural circulation reactor requiring no pumps to circulate the water through the core.
Nuclear physics parameters of the Wolsung CANDU-PHW reactor are computed by use of the PHWCELL computer code that is an improved version of LATREP. The PHWCELL code mainly computes cell parameters of heavy water moderated reactors, and modeling scheme of heavy water reactor cell calculations has been developed with the PHWCELL computer code. The reactor operating conditions considered in the study are cold zero power (CZP) and hot full power (HFP) with equilibrium poison. The cell parameters are also computed as a function of fuel burnup and the numerical results are compared with the results in PSR of the Wolsung unit and in the previous study. (author).
The risk analysis was carried out in consideration of conditions prevailing at the Kalkar site analogous to the investigations in phase A of DRS (German Reactor Study). Earthquake design loads include the probabilities of upper deviations of the site intensities to be expected. The calculations of dynamic loads for select buildings are made using models and computational methods. Component analyses were performed analogous to DRS for the supports of large components, supports of the roof construction of the reactor building taking into account support reserves due to plastic work capacity, wall disks in steam generator buildings and switchboard plant buildings. (DG).
Object: To limit the discharge amount of reactor water in a primary system at the time of scram to prevent excessive outflow of reactor water outside the system. Structure: A signal from an upper limit position indicator detects the fact that control rods are completely inserted when the reactor is urgently stopped and the detection signal causes a valve in an outflow line of the discharge water from a control rod driving mechanism to be closed to limit the amount of discharge flown into the scram discharge vessel, thus preventing outflow of reactor water in the primary system after the scram has been initiated. (Kamimura, M.).
Modelling the behaviour of fission product (FP) in a nuclear reactor coolant system (RCS) undergoing a hypothetical severe accident is an important step in the evaluation of radioactive release outside a nuclear power plant. This paper scrutinize Small Break LOCA sequence for WWER1000 reactor in order to investigate the possible paths for release of FP from fuel pallets to the reactor containment. Contemporaneous computer code for simulation of RCS will be use for the analysis. The results from analysis of fuel damage and release of FP trough the break of cold leg are present. (author)
... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...
Since January, 1981, the project of development of nuclear fuel fabrication technology for Wolsung reactor (CANDU type) was undertaken by KAERI(Korea Advanced Energy Research Institute) and successfully fulfilled with loading 24 fuel bundles made by KAERI in Wolsung reactor in September, 1984. On the basis of this accumulated technology and experience, mass production plan to supply all the nuclear fuels for Wolsung reactor is under way. In this presentation, the Korean experience in the development of the nuclear fuel fabrication technology, safety and performance evaluation of KAERI fuel and the results of irradiation of KAERI fuels in Wolsung reactor will be described.
Since January, 1981, the project of development of nuclear fuel fabrication technology for Wolsung reactor (CANDU type) was undertaken by KAERI(Korea Advanced Energy Research Institute) and successfully fulfilled with loading 24 fuel bundles made by KAERI in Wolsung reactor in September, 1984. On the basis of this accumulated technology and experience, mass production plan to supply all the nuclear fuels for Wolsung reactor is under way. In this presentation, the Korean experience in the development of the nuclear fuel fabrication technology, safety and performance evaluation of KAERI fuel and the results of irradiation of KAERI fuels in Wolsung reactor will be described.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
Purpose : To obtain an emergency core cooling device in a FBR type reactor by utilizing heat pipes which are not actuated at usual operation condition but actuated reliably upon emergency. Constitution : A system for injecting heat medium into heat pipes is provided. By injecting the heat medium into the heat pipes upon emergency to actuate the heat pipes, the reactor core is cooled. During normal reactor operation, the inside of the heat pipes is evacuated from a vacuum pump and no heat medium is filled therein, whereby unnecessary heat loss during the normal operation can be prevented. (Ikeda, J.).
Conceptual fusion reactor studies over the past 10 to 15 years have projected systems that may be too large, complex, and costly to be of commercial interest. One main direction for improved fusion reactors points towards smaller, higher-power-density approaches. First-order economic issues (i.e., unit direct cost and cost of electricity) are used to support the need for more compact fusion reactors. A generic fusion physics/engineering/costing model is used to provide a quantiative basis for these arguments for specific fusion concepts.
In 1980 Sasol completed its very large coal conversion complex, Sasol Two and Three in South Africa. This complex, the largest coal-to-liquids facility in the world, utilizes Sasol's proprietary Fischer-Tropsch technology, the Synthol Process. The two key elements of the Synthol Process are its catalyst and its unique fluidized bed reactor, the Synthol Circulating Fluidized Bed Reactor. Details on the catalytic aspects and reaction mechanism have been given elsewhere. In this paper, the history of the development of the reactor is discussed.
The addition of ZnO, depleted in the Zn-64 isotope, to the water of boiling water nuclear reactors lessens the accumulation of Co-60 on the reactor interior surfaces, reduces radioactive wastes and increases the reactor service-life because of the inhibitory action of zinc on inter-granular stress corrosion cracking. To the same effect depleted zinc in the form of acetate dihydrate is used in pressurized water reactors. Gas centrifuge isotope separation method is applied for production of depleted zinc on the industrial scale. More than 20 years of depleted zinc application history demonstrates its benefits for reduction of NPP personnel radiation exposure and combating construction materials corrosion.
This paper reports that, to obtain better simulation results for a Canada deuterium uranium (CANDU) reactor operation, a new simulation method is developed that uses actual detector readings as a correction factor. Detector readings from a CANDU reactor are used to correct the calculated flux distribution during core calculation iterations. A suitable function is found to describe the relationship between the detector flux and the fluxes of mesh points around the detector. The new simulation method is tested by performing numerical calculations for the Wolsung reactor (a CANDU-600). The results show that the new method predicts the core state more accurately with fewer iterations.
The Fast Flux Test Facility near Richland, Washington, utilizes computer control for reactor refueling and other related core component handling and processing tasks. The computer controlled tasks described in this paper include core component transfers within the reactor vessel, core component transfers into and out of the reactor vessel, remote duct measurements of irradiated core components, remote duct cutting, and finally, transferring irradiated components out of the reactor containment building for off-site shipments or to long term storage. 3 refs., 16 figs.
Progress in the construction of Candu reactors at home and abroad is surveyed. Some A.E.C.L. research projects are also mentioned. During 1979, Candu reactors again showed their superior capacity factors, four of them being among the ten most reliable reactors in the world. Progress in construction at Pickering B, Bruce B, Point Lepreau, Gentilly-2, Darlington, Wolsung (Korea), Cordoba (Argentina), and Cernavoda (Romania) is recounted. In 1979, it was unfortunately necessary to replace installed steam generators at Pickering B, Bruce B, Point Lepreau and Gentilly-2. At Wolsung, the reactor was pre-assembled before installation, which is a new technique. (N.D.H.).
... be easily replaceable, and its compartment or container ... in a simple, efficient manner for storage or disposal. ... and enters the reactor at approximatel ...
Various schemes of cooling have been investigated for the purpose of assessing potential benefits on the operational characteristics of the Syrian MNSR reactor. A detailed thermal hydraulic model for the analysis of MNSR has been developed. The analysis shows that an auxiliary cooling system, installed in the pool which surrounds the lower section of the reactor vessel, will significantly offset the consumption of excess reactivity due to the negative reactivity temperature coefficient, Hence, the maximum operating time of the reactor is extended. Compared with experimental data, the suggested model proves to be valid for the analysis of MNSR behavior under both steady state and transient conditions. (author)
A novel device called the gas expansion model (GEM) is being developed at the Hanford Engineering Development Laboratory for testing in the 400-MW(th) fast flux test facility (FFTF) reactor. Incorporation of the GEM into liquid-metal reactor designs is intended to measurably contribute to the achievement of inherent safety, by allowing the reactor to passively shut down even in the extremely remote (hypothetical) event of an unprotected (no scram) loss-of-flow accident. The purpose of this paper is to describe the GEM and present predictive analyses of the effectiveness of the device during unprotected loss-of-flow experiments in the FFTF.
A novel device called the gas expansion model (GEM) is being developed at the Hanford Engineering Development Laboratory for testing in the 400-MW(th) fast flux test facility (FFTF) reactor. Incorporation of the GEM into liquid-metal reactor designs is intended to measurably contribute to the achievement of inherent safety, by allowing the reactor to passively shut down even in the extremely remote (hypothetical) event of an unprotected (no scram) loss-of-flow accident. The purpose of this paper is to describe the GEM and present predictive analyses of the effectiveness of the device during unprotected loss-of-flow experiments in the FFTF.
This is the sixth book on reactor materials published under sponsorship of the Naval Reactors Office of the United States Department of Energy, formerly the United States Atomic Energy Commission. This book presents a comprehensive compilation of the most significant properties of thorium dioxide, much like the book Uranium Dioxide: Properties and Nuclear Applications presented information on the fuel material used in the Shippingport Pressurized Water Reactor core.
This document presents the integrated reactors concepts by a presentation of four reactors: PIUS, SIR, IRIS and CAREM. The core conception, the operating, the safety, the economical aspects and the possible users are detailed. From the performance of the classical integrated PWR, the necessity of new innovative fuels utilization, the research of a simplified design to make easier the safety and the KWh cost decrease, a new integrated reactor is presented: SCAR 600. (A.L.B.)
The heavy water reactor such as Wolsung No.1 and No.2 has a purification system to purify the reactor coolant. The control system regulates the coolant temperature to protect the ion exchanger. After the fuel exchanges of operating plant, the increase of the coolant pressure makes the purification temperature control difficult. In this paper, the controllability of the control dynamics of the purification system was analysed and the optimal parameters were proposed. To reduce the effects of the flow disturbance, the feedforward control structure was proposed and analysed.
The status of neutron activation cross sections for some threshold reactions important for reactor materials dosimetry is reviewed. An attempt is made to understand and explain discrepancies between integral and differential data, using recent available experimental results. The importance of standard and benchmark neutron fields for testing differential data for reactor dosimetry is emphasized and the Interlaboratory Reaction Rate (ILRR) program, as well as a similar program pursued by the IAEA, are briefly described.
The availability of reactor-produced radioisotopes in the United States for use in medical research and nuclear medicine has traditionally depended on facilities which are an integral part of the US national laboratories and a few reactors at universities. One exception is the reactor in Sterling Forest, New York, originally operated as part of the Cintichem (Union Carbide) system, which is currently in the process of permanent shutdown. Since there are no industry-run reactors in the US, the national laboratories and universities thus play a critical role in providing reactor-produced radioisotopes for medical research and clinical use. The goal of this survey is to provide a comprehensive summary of these production capabilities. With the temporary shutdown of the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) in November 1986, the ...
Field reversed configuration (FRC) is a prospective high ? magnetic system for high efficiency D- 3He fusion reactor. Self-consistent FRC plasma profiles and static electric field for reactor calculations are discussed in framework of the model including flow equilibrium and collisionless transport equations. The extrapolations to reactor regimes of plasma confinement scaling laws are considered.
As part of a handbook on the efficient use of energy a chapter is included which is intended to give an appreciation of the principles and problems involved in the generation of nuclear power. The subject is discussed under the following headings: introductory nuclear physics; basic reactor physics; thermal reactors; fast reactors; fuel reserves and utilization; environmental considerations; nuclear fusion. (U.K.).
High pressure experiments in a jet-stirred reactor have been performed to study the NO{sub x} formation in lean premixed combustion of methane/air mixtures. The experimental results are compared with numerical predictions using four well known reaction mechanisms and a model which consists of a series of two perfectly stirred reactors and a plug flow reactor. (author) 2 figs., 7 refs.
The European Research and Development Program on decay heat removal by natural convection for the European Fast Reactor (EFR) covers the calculational methods and the model experiments performed for code validation. The studies concentrate on important physical effects of the cooling modes within the primary system and the direct reactor cooling circuits and include fundamental tests as well as reactor experiments. (author)
Wolsung nuclear power plant has experienced four occasions of reactor shutdown owing to heavy water leaks since its commercial operation. Among these heavy water leaks, only one case was acute and brought about reactor shutdown but the other cases listed below were chronic and repaired after manual reactor shutdown. (author). 4 tabs., 10 figs.
To seek for a promising concept of a heavy liquid metal coolant (HLMC) fast reactor plant, Japan Nuclear Cycle Development Institute (JNC) and the electric utilities conducted conceptual design study on various types of plant concepts and compared these concepts based on technical feasibility and economical perspective. The Pb-Bi cooled complete natural circulation reactor concept may attain high safety level and construction cost goal (Yen 200,000/kWe) (authors)
The Department of Energy Office of Fissile Materials Disposition (DOE/MD) initiated a detailed analysis activity to evaluate each of ten plutonium disposition alternatives that survived an initial screening process. This document, Volume 2 of a four volume report, summarizes the results of these analyses for the CANDU reactor based plutonium disposition alternative.
The concept of preliminary transmutation of minor actinides before placement to the long-term storage is considered. The purpose of such preliminary transmutation before ultimate storage is to incinerate a part of actinides and to transform another part into new actinides providing low level of radiotoxicity accumulated in the storage. Modes of transmutation in reactors of PWR, PHWR (CANDU), and Superfenix types are compared. Among power reactors, heavy-water PHWR type reactor is most acceptable for preliminary transmutation. (author)
The Fast Flux Test Facility (FFTF) bottom-loading transfer cask (BLTC) system is designed to provide ex-vessel fuel transfers of irradiated reactor components between the reactor containment building and the LMFBR shipping cask in the reactor service building. This system is being procured from National Lead Industries, Wilmington, Delaware, under management of Aerojet Manufacturing Company.
Afterheat represents an important consideration in design of conceptual fusion power reactors, particularly during normal or unplanned shutdown. Afterheat calculations have been undertaken for various generic designs, but with special reference to the Culham DEMO reactor. These calculations have included the redistribution of heating by gamma ray transport. Selected temperature response calculations have been undertaken. (author).
The Integral Fast Reactor is an innovative liquid metal reactor concept that is being developed by Argonne National Laboratory. It takes advantage of the properties of metallic fuel and liquid metal cooling to offer significant improvements in reactor safety, operation, fuel cycle economics, environmental protection, and safeguards. The plans for demonstrating the IFR fuel cycle, including its waste processing options, by processing irradiated fuel from the Experimental Breeder Reactor-II fuel in its associated Fuel Cycle Facility have been developed for the first refining series. This series has been designed to provide the data needed for the further development of the IFR program. An important piece of the data needed is the recovery of TRU material during the reprocessing and waste operations.
The Integral Fast Reactor is an innovative liquid metal reactor concept that is being developed by Argonne National Laboratory. It takes advantage of the properties of metallic fuel and liquid metal cooling to offer significant improvements in reactor safety, operation, fuel cycle economics, environmental protection, and safeguards. The plans for demonstrating the IFR fuel cycle, including its waste processing options, by processing irradiated fuel from the Experimental Breeder Reactor-II fuel in its associated Fuel Cycle Facility have been developed for the first refining series. This series has been designed to provide the data needed for the further development of the IFR program. An important piece of the data needed is the recovery of TRU material during the reprocessing and waste operations.
One of the characteristic safety features of a pool type research reactor is a safety flapper valve. The valve enables natural convection cooling mechanism in one of the following events. (a) Opening flapper valve promote decay heat removal following reactor's shutdown. (b) Also the valve is gravity driven. There is a possibility that the valve fails to open when it is required to do so. In the present paper the cooling characteristics of the core are analyzed for this event. A steady state study was performed for 5 MW power and 18 FE following a reactor shutdown. It is shown that enough margin exists to assure adequate reactor core cooling should the safety flapper valve fails to open. (authors)
Conceptual fusion reactor studies over the past 10-15 yr have projected systems that may be too large, complex, and costly to be of commercial interest. One main direction for improved fusion reactors points toward smaller, higher-power-density approaches. First-order economic issues (i.e., unit direct cost and cost of electricity) are used to support the need for more compact fusion reactors. The results of a number of recent conceptual designs of reversed-field pinch, spheromak, and tokamak fusion reactors are summarized as examples of more compact approaches. While a focus has been placed on increasing the fusion-power-core mass power density beyond the minimum economic threshold of 100-200 kWe/tonne, other means by which the overall attractiveness of fusion as a long-term energy source are also addressed.
This paper discusses how the U.S. Liquid Metal Reactor Development Program has been restructured to carry out R and D on advanced reactor technology. The program gives particular emphasis to improvements to reactor safety. The new directions are based on the technology of the integral fast reactor (IFR). Much of the basis for superior safety performance using IFR technology has been experimentally verified and aggressive programs continue in EBR-II and TREAT. Progress has been made in demonstrating both the metallic fuel and the new electrochemical processes of the IFR. The FFTF facility is converting to metallic fuel; however, FFTF also maintains a considerable U.S. program in oxide fuels. In addition, generic programs are continuing in steam generator testing, materials development, and with international cooperation, aqueous reprocessing.
The Advanced MAPLE is a research reactor design under development as a high-flux neutron source. The main performance goals for the reactor are a high peak thermal neutron flux in a heavy-water reflector tank, and a high average fast neutron flux in a central irradiation facility, with a maximum linear fuel rod rating of less than 120 kW/m. This study investigated the neutronic and reactor design consequences of the use of H_2O coolant as opposed to D_2O. The neutronics results, and several other considerations, indicate that H_2O coolant has a number of advantages. It is suggested that the H_2O coolant option be considered in the design of the Advanced MAPLE reactor. (L.L.) 9 refs., 4 figs., tab.
A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and experimentally verified, which uses a mid-ranging control structure to increase the operating range of the hydraulic equipment. A Model Predictive Controller is proposed to maximize the conversion under hard input and state constraints. An extended Kalman filter is designed to estimate unmeasured concentrations and parameters. Simulations show that the designed control system gives high conversion ...
The PERMCAT is a membrane reactor proposed for processing fusion reactor plasma exhaust gas: tritium removal is obtained by isotopic swamping operating in counter-current mode. In this work, a membrane reactor using a permeator tube of length about 500 mm produced via diffusion welding of Pd-Ag thin foils is described. An appropriate mechanical design of the membrane module has been developed in order to avoid any significant compressive and bending stresses on the very long and thin wall permeator tube: two expanded bellows have been applied to the Pd-Ag tube, so that it has been pre-tensioned before operating. The elongation of the metal permeator under hydrogenation has been theoretically estimated and experimentally verified for properly designing the membrane reactor.
SMART (System-Integrated Modular Advanced Reactor) is a first-of-the-kind integral reactor with 330 MW thermal power under active development by Korea Atomic Energy Research Institute (KAERI) for power generation and seawater desalination. SMART employs various design features that are not typically found in other nuclear power plants. Examples include a unique passive residual heat removal system (PRHRS), and enclosure of a pressurizer, eight helical steam generators, and eight canned reactor coolant pumps inside the reactor pressure vessel. This paper presents risk insights on the SMART reactor gained during the development of a regulatory PSA model by Korea Institute of Nuclear Safety (KINS)
Purpose: To stably control the reactor water level so as not to cause excess water feeding in a BWR type reactor. Constitution: A flow control valve is disposed to the exit of a feedwater pump for a nuclear reactor and the valve is controlled by a flow regulator to maintain the water level constant in the reactor. A signal from a water level controller is inputted to the flow regulator to thereby control the flow rate control valve. In this case, the flow regulator remains in a saturated state just after the starting of the feedwater pump, in which the pump flowrate is at 100% to result in an excess water feeding condition. In view of the above, a feedback circuit is provided to the flow regulator so that the saturated state is eliminated and the water feeding can be controlled directly from the water level controller. (Kamimura, M.).
As an integral part of the Fast Test Reactor Vibration Program for Reactor Internals, the flow-induced vibrational characteristics of scaled Fast Test Reactor core internal and peripheral components were assessed under scaled and simulated prototype flow conditions in the Hydraulic Core Mockup. The Hydraulic Core Mockup, a 0.285 geometric scale model, was designed to model the vibrational and hydraulic characteristics of the Fast Test Reactor. Model component vibrational characteristics were measured and determined over a range of 36 percent to 111 percent of the scaled prototype design flow. Selected model and prototype components were shaker tested to establish modal characteristics. The dynamic response of the Hydraulic Core Mockup components exhibited no anomalous flow-rate dependent or modal characteristics, and prototype response predictions were adjudged acceptable.
A series of experiments is to be made during the acceptance test program of the Fast Flux Test Facility (FFTF) to measure the gamma ray characteristics of the Fast Test Reactor (FTR) and to establish the performance characteristics of the reactor shield. These measurements are a part of the FFTF Reactor Characterization Program (RCP). Detailed plans have been developed for these experiments. During the initial phase of the Characteristics Program, which will be carried out in the In-Reactor Thimble (IRT), both active and passive measurement methods will be employed to obtain as much information concerning the gamma ray environment as is practical. More limited active gamma ray measurements also will be made in the Vibration Open Test Assembly (VOTA).
Preparations are under way for the initial startup and testing of the Fast Flux Test Facility (FFTF). The FFTF Reactor Characterization Program is that part of the startup test plan that deals with the determination of the neutron, gamma ray and thermal hydraulic characteristics of the reactor. This program encompasses measurements and calculations of: neutron spectra, flux and fluence; gamma-ray spectra, dose and heating; fission rate distributions; capture rate distributions; other reaction rates of interest; fission product yields; and thermal hydraulic data. Measurements of these parameters will be made in the reactor core and reflectors, will extend vertically downward to the vicinity of the core support structure and upward to the top of the sodium pool, and will extend radially outward to include in-vessel fuel storage locations and the cavity between the reactor vessel and the concrete wall.
The deliveration by the Nuclear Safety Commission was commenced on the alteration in reactor installation, as it had been inquired by the Ministry of International Trade and Industry. The alteration is the additional installation of the reactor No. 2 in the Sendai Nuclear Power Station, Kyushu Electric Power Co., Inc. It is a PWR power plant with thermal output of about 2,660 MW (electric output of 890 MW), to be installed, adjoining to the reactor No. 1 of the same type and capacity under construction. In the examination by MITI, it was confirmed that the technological capabilities for its construction and operation and the radiation protection measures in power generation are both sufficient. The contents of the examination include the siting conditions, the location and construction of reactor facilities, etc. (J.P.N.).
The deliberation by the Nuclear Safety Commission was initiated on the alteration in reactor installation, as was required by the Ministry of International Trade and Industry. The alteration is the additional installation of the reactor No. 2 in the Sendai Nuclear Power Station, Kyushu Electric Power Co., Inc. It is a PWR power plant with thermal output of about 2,660 MW (electric output of 890 MW), to be installed, adjoining to the reactor No. 1 of the same type and capacity under construction. In the examination by MITI, it was confirmed that the technological capabilities for its construction and operation and the radiation protection measures in power generation are both sufficient. The contents of the examination include the siting conditions, the location and construction of reactor facilities, etc.
The swelling and in-reactor creep behaviors of the PCA alloy have been determined from the irradiation of pressurized tube specimens in the FFTF reactor. These data have been obtained to a peak neutron fluence corresponding to approximately 80 dpa in the FFTF reactor for irradiation temperatures between 400 and 750/sup 0/C. Diametral measurements performed on the unstressed specimens indicate the possible onset of swelling in the PCA alloy for irradiation temperatures between 400 and 550/sup 0/C and at a neutron fluence corresponding to approx.50 dpa. The creep data suggest a non-linear fluence dependence and linear stress dependence (for hoop stresses less than 100 MPa) which is consistent with the in-reactor creep behavior of many cold worked austenitic stainless steels. These PCA creep data are compared to available 316 SS in-reactor creep data. The ...
The swelling and in-reactor creep behaviors of the PCA alloy have been determined from the irradiation of pressurized tube specimens in the FFTF reactor. These data have been obtained to a peak neutron fluence corresponding to approximately 80 dpa in the FFTF reactor for irradiation temperatures between 400 and 750"0C. Diametral measurements performed on the unstressed specimens indicate the possible onset of swelling in the PCA alloy for irradiation temperatures between 400 and 550"0C and at a neutron fluence corresponding to #approx#50 dpa. The creep data suggest a non-linear fluence dependence and linear stress dependence (for hoop stresses less than 100 MPa) which is consistent with the in-reactor creep behavior of many cold worked austenitic stainless steels. These PCA creep data are compared to available 316 SS in-reactor creep data. The in-reactor creep ...
SMART (System integrated Modular Advanced ReacTor) , is under development at the Korea Atomic Energy Research Institute (KAERI). SMART is an integral type pressurized water reactor which contains a pressurizer, 4 reactor coolant pumps (RCPs), and 8 steam generator cassettes(S/Gs) in a single reactor vessel. This reactor has substantially enhanced its safety with an integral layout of its major components, 4 trains of safety injection system (SIS), and an adoption of 4 trains of passive residual heat removal system (PRHRS) instead of an active auxiliary feedwater system . The thermal power is 330 MWth. During the conceptual design stage, a preliminary PSA was performed. PSA results identified that a steam generator tube rupture (SGTR) is one of the most important initiating events which results in a high core damage frequency. Clear understanding of accident progression with various ...
The long operating cycle simplified boiling water reactor is a reactor concept that pursues both safety and the economy by employing a natural circulation reactor core without a refueling, a passive decay heat removal, and an integrated building for the reactor and turbine. Throughout the entire spectrum of the design basis accident, the reactor core is kept covered by the passive emergency core cooling system. The decay heat is removed by the conventional active low-pressure residual heat removal system. As for a postulated severe accident, the suppression pool water floods the lower part of the reactor pressure vessel (RPV) in the case when core damage occurs, and the in-vessel retention that keeps the melt inside the RPV is achieved by supplying the coolant. The containment adopts a parallel-double-steel-plate structure similar to a hull structure, which ...
A study has been made of the reactor blockages occurring in the course of direct hydroliquefaction of Miike coal, Taiheiyo coal and Yallourn coal briquets in a tubular reactor. The liquefaction tests were carried out at 450 C under 24.6 MPa hydrogen pressure, with red mud and sulfur catalyst. From the observed balances for catalyst and coal ash, it was inferred that reactor blockages are due to sedimentation of catalyst and ash. The conditions for catalyst and coal ash run-off were determined after solvent and slurry flow rates had been altered to suit the type of coal being tested. It was found that ash run-off occurred more readily as the difference between the slurry flow velocity and the natural sedimentation velocity of red mud in the coal liquids increased. Even when ash run-off was occurring, however, the ash concentration of the slurry in the reactor was higher than the concentration in the feed ...
One of the key features of ANL's Integral Fast Reactor (IFR) concept is a close-coupled fuel cycle. The proposed fuel cycle is similar to that demonstrated over the first five to six years of operation of EBR-II, when a fuel cycle facility adjacent to EBR-II was operated to reprocess and refabricate rapidly fuel discharged from the EBR-II. Locating the IFR and its fuel cycle facility on the same site makes the IFR a self-contained system. Because the reactor fuel and the uranium blanket are metals, pyrometallurgical processes (shortned to ''pyroprocesses'') have been chosen. The objectives of the IFR processes for the reactor fuel and blanket materials are to (1) recover fissionable materials in high yield; (2) remove fission products adequately from the reactor fuel, e.g., a decontamination factor of 10 to 100; and (3) upgrade the concentration of plutonium ...
Calculations have been made to determine the production of "1"8"8W from "1"8"6W in several US fission reactor systems, e.g., Fast Flux Test Facility (FFTF), the High Flux Isotope Reactor (HFIR), and the Advanced Test Reactor (ATR). Important input to these calculations are the cross-section parameters for "1"8"6W, "1"8"7W, and "1"8"8W. Only two values have been measured for "1"8"7W and none for "1"8"8W. Consequently, results from integral measurements play a crucial role in determining the "1"8"7W and "1"8"8W values. This has been studied for irradiations in the FFTF and the Oregon State Univ. (OSU) research reactor. Short irradiation of enriched "1"8"6W in both the FFTF and the OSU reactors have produced #mu#Ci/g quantities of "1"8"8W/"1"8"8Re. Measurements were made of the "1"8"8W gamma ray emission. These results were incorporated with other available data to provide more ...
With the objective to improve the reactor physics calculation on a 2D and 3D nuclear reactor via the Diffusion Equation, an adaptive automatic finite element remeshing method, based on the elementary area (2D) or volume (3D) constraints, has been developed. The adaptive remeshing technique, guided by a posteriori error estimator, makes use of two external mesh generator programs: Triangle and TetGen. The use of these free external finite element mesh generators and an adaptive remeshing technique based on the current field continuity show that they are powerful tools to improve the neutron flux distribution calculation and by consequence the power solution of the reactor core even though they have a minor influence on the critical coefficient of the calculated reactor core examples. Two numerical examples are presented: the 2D IAEA reactor core numerical benchmark and the 3D model ...
A generic reactor model is used to examine the economic viability of electricity generation by magnetic fusion. The simple model uses components which are representative of those used in previous reactor studies of deuterium-tritium burning tokamaks, stellarators, bumpy tori, reverse field pinches and tandem mirrors. Conservative costing assumptions are made. The generic reactor is not a tokamak but rather it is intended to emphasize what is common to all magnetic fusion reactors. The reactor uses a superconducting toroidal coil set to produce the dominant magnetic field. To this extent it is a less good approximation to systems, such as the reversed field pinch in which the main field is produced by a plasma current. The main output of the study is the cost of electricity as a function of the weight and size of the fusion core - blanket, shield, structure and coils. The model shows ...
The steam generator low water level trip setpoint of KORI NPP units 3 and 4(KNU 3 and 4), three-loop Westinghouse pressurized water reactor, is higher than that of OPR1000. In addition, steam generator downcomer water level in KNU 3 and 4 could fluctuate easily during a transient because of smaller downcomer water inventory, compared to the total water inventory in the steam generator. Due to these reasons, there is a higher possibility of unnecessary reactor trips caused by the steam generator low-low water level in KNU 3 and 4. Its operating history shows that most of reactor trips were caused by steam generator low-low level reactor trip signal. Such reactor trips, especially unnecessary ones, result in time and economic losses. In this paper, a feasibility study was performed to reduce unnecessary reactor trip by changing steam generator low-low water level ...
The steam generator low water level trip setpoint of KORI NPP units 3 and 4(KNU 3 and 4), three-loop Westinghouse pressurized water reactor, is higher than that of OPR1000. In addition, steam generator downcomer water level in KNU 3 and 4 could fluctuate easily during a transient because of smaller downcomer water inventory, compared to the total water inventory in the steam generator. Due to these reasons, there is a higher possibility of unnecessary reactor trips caused by the steam generator low-low water level in KNU 3 and 4. Its operating history shows that most of reactor trips were caused by steam generator low-low level reactor trip signal. Such reactor trips, especially unnecessary ones, result in time and economic losses. In this paper, a feasibility study was performed to reduce unnecessary reactor trip by changing steam generator low-low water level ...
The experience base regarding fission product behavior developed during the Rover program, the nuclear rocket development program of 1955--1972, will be useful in planning a renewed nuclear rocket program. During the Rover program, 20 reactors were tested at the Nuclear Rocket Development Station in Nevada. Nineteen of these discharged effluent directly into the atmosphere; the last reactor tested, a non-flight-prototypic, fuel-element-testing reactor called the Nuclear Furnace (NF-1) was connected to an effluent cleanup system that removed fission products before the hydrogen coolant (propellant) was discharged to the atmosphere. In general, we are able to increase both test duration and fuel temperature during the test series. Therefore fission product data from the later part of the program are more interesting and more applicable to future reactors. We have collected fission product retention (and ...
This report discusses Test Campaign TC07 of the Kellogg Brown & Root, Inc. (KBR) Transport Reactor train with a Siemens Westinghouse Power Corporation (Siemens Westinghouse) particle filter system at the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama. The Transport Reactor is an advanced circulating fluidized-bed reactor designed to operate as either a combustor or a gasifier using a particulate control device (PCD). The Transport Reactor was operated as a pressurized gasifier during TC07. Prior to TC07, the Transport Reactor was modified to allow operations as an oxygen-blown gasifier. Test Run TC07 was started on December 11, 2001, and the sand circulation tests (TC07A) were completed on December 14, 2001. The coal-feed tests (TC07B-D) were started on January 17, 2002 and completed on April 5, 2002. Due to operational difficulties with the ...
The liquefaction reaction system of an NEDOL process coal liquefaction 1t/d PSU was opened and checked to investigate the cause of the rise of differential pressure between liquefaction reactors of the PSU. The liquefaction test at a coal concentration of 50 wt% using Tanito Harum coal was conducted, and it was found that the differential pressure between reactors was on the increase. By the two-phase flow pressure loss method, deposition thickness of deposit in pipelines was estimated at 4.4mm at the time of end operation, which agreed with a measuring value obtained from a {gamma} ray. The rise of differential pressure was caused by deposit formation in pipelines connecting reactors. The main component of the deposit is calcite (CaCO3 60-70%) and is the same as the usual one. It is also the same type as the deposit on the reactor wall. Ca in coal ash is concerned with this. To withdraw solid matters ...
The neutron data required to completely analyze fission reactors includes many isotopes and covers a broad energy range. In both fast and thermal reactors, the neutron inventory is a fine balance determined by the fission properties of "2"3"5U, "2"3"9Pu and "2"3"8U and by the capture cross sections of "2"3"8U, fuel materials, structural materials and coolant materials. In fast reactors, the spectrum of neutrons ranges from 1 keV to 3 MeV and is influenced by the elastic and inelastic scattering properties of "2"3"8U and the structural and coolant materials. For neutron shielding applications, the important neutron data include the total cross sections of structural and coolant materials in the MeV range. The impact of these basic nuclear data in fission reactor applications is most suitably described by sensitivity analysis. For example, sensitivity coefficients computed for a typical large plutonium ...
The Fixed Bed Nuclear Reactor (FBNR) is a small 40 MWe reactor based on the Pressurized Water Reactor (PWR) technology. FBNR is an integrated primary circuit and simple in design. It has the characteristics of being small, modular, proliferation resistant, inherently safe and passively cooled reactor with reduced adverse environmental impact. It utilizes the fuel designed for high temperature reactors operating in a relatively low temperature of PWR environment The 15 mm diameter spherical fuel elements are made of TRISO type microspheres embedded in graphite and cladded by SiC. The coolant flow transfers them from the fuel chamber into the core and become fixed forming a suspended core. Any accident signal will cut off the power to the coolant pump causing a stop in the flow. This results in making the fuel elements fall out of the reactor core by the force of ...
In March 2007 in-pile testing of LEU U-Mo full-size IRT type fuel elements was started in the MIR reactor. Four prototype fuel elements for Uzbekistan WWR SM reactor are being tested simultaneously - two of tube type design and two of pin type design. The dismountable irradiation devices were constructed for intermediate reloading and inspection of fuel elements during reactor testing. The objective of the test is to obtain the experimental results for determination of more reliable design and licensing fuel elements for conversion of the WWR SM reactor. The heat power of fuel elements is measured on-line by thermal balance method. The distribution of fission density and burn-up of uranium in the volume of elements are calculated by using the MIR reactor MCU code (Monte-Carlo) model. In this paper the design of fuel elements, the technique, main parameters and preliminary results ...
Decay heat removal analyses for lead-bismuth cooled natural circulation reactors are described in this paper. A combined multi-dimensional plant dynamics code (MSG-COPD) has been developed to conduct the system analysis for the natural circulation reactors. For the preliminary study, transient analysis has been performed for a 100 MWe lead-bismuth-cooled reactor designed by Argonne National Laboratory (ANL). In addition, decay heat removal characteristics of a 400 MWe lead-bismuth-cooled natural circulation reactor designed by Japan Nuclear Cycle Development Institute (JNC) has been evaluated by using MSG-COPD. PRACS (Primary Reactor Auxiliary Cooling System) is prepared for the JNC's concept to get sufficient heat removal capacity. During 2000 sec after the transient, the outlet temperature shows increasing tendency up to the maximum temperature of 430 Centigrade, because ...
Validation of nuclear power reactor signals is often performed by comparing signal prototypes with the actual reactor signals. The signal prototypes are often computed based on empirical data. The implementation of an estimation algorithm which can make predictions on limited data is an important issue. A new machine learning algorithm called support vector machines (SVMS) recently developed by Vladimir Vapnik and his coworkers enables a high level of generalization with finite high-dimensional data. The improved generalization in comparison with standard methods like neural networks is due mainly to the following characteristics of the method. The input data space is transformed into a high-dimensional feature space using a kernel function, and the learning problem is formulated as a convex quadratic programming problem with a unique solution. In this paper the authors have applied the SVM method for data-based state estimation in nuclear ...
Tarapur Atomic Power Station Unit-3 and 4 (TAPS -3 and 4) are the 540 MWe reactors. Unit-4 attained first criticality on 06th March 2005 and operated for about 230 effective full power days (EFPD). Unit-3 attained first criticality on 21st May 2006 and operated for about 20 EFPD. With the reactor operation radiation field increases on the Primary Heat Transport system equipments, Moderator system equipments and auxiliary system equipments due to deposition of fission products and activation products in different reactor systems. These dose rates significantly contributes to the external exposure and stations collective dose during reactor operation, refueling operation and maintenance activities. A study was undertaken at TAPS 3 and 4 to identify the system equipments showing the significant dose rates and identify the radionuclides present in the primary heat transport system, Moderator systems, cover ...
A review of the status of integral measurements is presented for "2"4"0Pu, "2"4"1Pu, "2"4"2Pu, "2"4"1Am and "2"4"3Am. This review includes integral measurements pertinent to thermal reactor systems, i.e., thermal cross sections and resonance integrals, as well as measurements for fast reactor systems. It appears that for these nuclides the data for thermal reactors are in good shape; however, more work is recommended in defining the branching ratio of the capture cross section of "2"4"1Am to the isomeric and ground states of "2"4"2Am. Also, benchmark irradiation data are needed for cross section data testing using depletion/production codes. For fast reactors, experiments are in progress, in the UK, in France, and also in the US, with partial results available at this time. Fast integral data obtained from these measurements will be very beneficial. The recommendation pertaining to "2"4"1Am and proper ...
Atomic Energy Regulatory Board carries out the regulatory review of the reactor physics design, commissioning and operational aspects through Project Design Safety Committee and Specialist Group of reactor physicists with wide experience in the design, commissioning and operational safety review of NPPs. TAPP-3 and 4 PHWRs, being the first indigenous design of 540 MWe Units, are quite different than the standard 220 MWe PHWRs. The safety review of reactor physics design was quite complex, as majority of the systems were new. The Reactor Physics Specialist Group carried out extensive safety review of 540 MWe PHWR reactor physics design and made significant contributions of design modifications and improvements in the operational procedures. Some salient contributions include: Monitoring the core during bulk addition of moderator without the availability of shutdown systems. Logics ...
This study describes the mechanical compatibility of the direct use of spent pressurized water reactor (PWR) fuel in Canada deuterium uranium (CANDU) reactors (DUPIC) fuel, when it is loaded into a CANDU reactor. The mechanical compatibility can be assessed for the fuel management, primary heat transport system, fuel channel, and the fuel handling system in the reactor core by both the experimental and analytic methods. Because the physical dimensions of the DUPIC fuel bundle adopt the CANDU flexible (CANFLEX) fuel bundle design which has already been demonstrated for a commercial use in CANDU reactors, the experimental compatibility analyses focused on the generation of material property data and the irradiation tests of the DUPIC fuel, which are used for the computational analysis. The intermediate results of the mechanical compatibility analysis have shown that the integrity of ...
This report has reviewed the construction of a cooling tower for the K reactor at the DOE Savannah River Site in Aiken, South Carolina. It has been found that the cooling tower would prevent further destruction of cypress and tupelo trees, would maintain a more consistent flow from site streams, and would allow earlier recovery of stream corridors inside a portion of the site. About 630 acres of wetlands have already been affected by the hot water discharged by the K reactor during the past 35 years. GAO believes that about 10 to 12 acres of additional damage would be prevented by the tower for every year the reactor is operated, and if current plans for re-start and retirement of the reactor are followed, less than 100 acres would be preserved. As requested, GAO also identified an example of a project that could be funded as compensation to the public for the damage the K reactor ...
Since the 1970's, global efforts have been going on to replace the high-enriched (>90% "2"3"5U), low-density UAlx research reactor fuel with high-density, low enriched (<20% "2"3"5U) replacements. This search is driven by the attempt to reduce the civil use of high-enriched material because of proliferation risks and terrorist threats. American initiatives, such as the Global Threat Reduction Initiative (GTRI) and the Reduced Enrichment for Research and Test Reactors (RERTR) program have triggered the development of reliable low-enriched fuel types for these reactors, which can replace the high enriched ones without loss of performance. Most success has presently been obtained with U_3Si_2 dispersion fuel, which is currently used in many research reactors in the world. However, efforts to search for a replacement with even higher density, which will also allow the conversion of some high flux ...
The Fast Flux Test Facility (FFTF) was designed to test fast-reactor fuels and other nonfuel materials. In its 37 reactor cycles of operations, the FFTF reactor has performed very well and successfully completed all the irradiation testings with an operating efficiency factor as high as 98%. Since FFTF is an experimental reactor, its core loading changed from cycle to cycle. Depending on the number of test assemblies in the core and their location, the core loading can change significantly from an essentially homogeneous core loading to a relatively nonhomogeneous or even highly localized heterogeneous loading. Consequently, the core reload design and initial criticality analyses were required for each operating cycle. The zero power initial critical control rod bank height was predicted before each reactor startup. The initial critical prediction depends on the reactivity ...
This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors from January 1997 to June 1997. Topics that have been investigated include (a) fatigue of carbon, low-alloy, and austenitic stainless steels (SSs) used in reactor piping and pressure vessels, (b) irradiation-assisted stress corrosion cracking of Types 304 and 304L SS, and (c) EAC of Alloys 600 and 690. Fatigue tests were conducted on ferritic and austenitic SSs in water that contained various concentrations of dissolved oxygen (DO) to determine whether a slow strain rate applied during various portions of a tensile-loading cycle is equally effective in decreasing fatigue life. Slow-strain-rate-tensile tests were conducted in simulated boiling water reactor (BWR) water at 288 C on SS specimens irradiated to a low fluence in the Halden reactor and the results ...
In an existent emergency reactor core cooling device, if a ruptures should occure in a pipeline of a gravitational dropping type reactor core cooling system pool (GDCS) due to some or other causes, a portion of GDCS pool water was flown out of the ruptured port and could not be used for reactor core cooling. Then, a difference pressure detector is disposed to a GDCS pipeline at the inlet of a reactor pressure vessel. When it is judged by the detector, that coolants flow to the outside of the injection pipeline, an injection value disposed to the GDCS pipeline is closed by the difference pressure signal. Even if a rupture should occur on the side of the pressure vessel at downstream to the check value of the GDCS pipeline, since backflow is caused at the pressure container inlet of the GDCS pipeline with the rupture port, the rupture is detected by the difference pressure detector to close the injection ...
A highly reliable control rod drive mechanism (CRDM) installed inside the reactor vessel has developed for use of an advanced marine reactor. This CRDM contributes to compactness and simplicity of the reactor system, and it can eliminate the possibility of a rod ejection accident. The CRDM works in the high temperature and high pressure water - 310degC and 12 MPa, the same atmosphere as the primary loop. Driving force is produced by a synchronous motor with the rotor of a permanent magnet, which has been developed. An innovative latch mechanism using separable ball nuts can latch driving shaft connecting the control rod and de-latch it for scram. The rod position detector using a magnetostrictive wire type sensor on the principle of Wiedeman effect has been developed, accuracy of which is verified to have a detecting error within 1.2 mm. Ball bearings for thrust and radial supports in rotation have been developed to be ...
Korea Atomic Energy Research Institute(KAERI) launched a project to develop an integral reactor in 1996. The reactor called as System Integrated Modular Advanced Reactor(SMART) which is a kind of small modular reactors (SMRs). Since the early 1990s, there has been renewed interest in the development and application of small and medium sized integral reactors. 2009 assessment by the IAEA under its Innovative Nuclear Power Reactor and Fuel Cycle (INPRO) program concluded that there could be 96 SMRs in operation around the world by 2030 in its 'high' case, and 43 units in the 'low' case, none of them in the USA. The reason of the increased demand mostly comes from the fact that SMRs are thought to be more suitable for developing countries with small electrical grid capacity, insufficient infrastructure and limited investment capability than developed ones. However, ...
A novel scheme is proposed to drive a low-power subcritical fuel assembly by means of a long Cylindrical Radially-convergent Inertial Electrostatic Confinement (CRIEC) used as a neutron source. The concept is inherently safe in the sense that the fuel assembly remains subcritical at all times. Previous work has been done for the possible implementation of CRIEC as a subcritical assembly driver for power reactors. However, it has been found that the present technology and stage of development of IEC-based neutron sources can not meet the neutron flux requirements to drive a system as big as a power reactor. Nevertheless, smaller systems, such as research and training reactors, could be successfully driven with levels of neutron flux that seem more reasonable to be achieved in the near future by IEC devices. The need for custom-made expensive nuclear fission fuel, as in the case of the TRIGA reactors, is ...
Sr3In0.9Co1.1O6, isostructural to Ca3Co2O6, is revealed by the study of the phase relations in the system SrO-InO1.5-CoOx (1000 oC). The structure of Sr3In0.9Co1.1O6 is refined by the combination of powder X-ray and neutron diffraction. Sr3In0.9Co1.1O6 crystallizes in a trigonal lattice with the cell parameters a=b=9.59438(3) A, c=11.02172(4) A with the space group R-3c. Its structure possesses 1D (In/Co)O3 chains running along the c-axis constructed by alternating face-sharing CoO6 octahedra and (In0.9Co0.1)O6 trigonal prisms. The co-occupation of In3+ and Co3+ at the trigonal prismatic site is evidenced by elementary analysis and determined by the structure refinement. Sr3In0.9Co1.1O6 is paramagnetic, and the susceptibility is consistent with the occupation of Co3+ at 10% of the trigonal prismatic positions in a high spin state (HS, S=2). The HS Co3+ is well separated by diamagnetic CoO6 octahedra and InO6 trigonal prisms and shows a g factor of 2.0 in the ...
Two US DOE projects in the Pacific Northwest offer unique on-the-scene training opportunities at sodium-cooled fast-reactor plants: the Fast Flux Test Facility (FFTF) near Richland, Washington, which has operated successfully in a wide range of irradiation test programs since 1980; and the Experimental Breeder Reactor II (EBR-II) near Idaho Falls, Idaho, which has been in operation for approximately 20 years. Training programs have been especially designed to take advantage of this plant experience. Available courses are described.
There is growing interest in using {sup 242m}Am as a nuclear fuel for space reactors and nuclear batteries. In this paper, we discuss different {sup 242m}Am enrichments, as well as fuel weight requirements, to produce a critical reactor. It was found that relatively low enrichments of {sup 242m}Am, about 10 w/o, are enough to guarantee criticality. Such low enrichments might eliminate the need for a {sup 242m}Am enrichment process. It was also found that the best results for low {sup 242m}Am requirements are obtained with a moderator to fuel volume ratio of 10,000.
Tritium dose management is an important aspect of the radiation protection program at CANDU type reactor sites. This paper describes the bioassay and dosimetry of tritium at CANDU reactor sites, especially for Wolsung Nuclear Power Plant. It presents a compilation of information drawn from published papers, technical reports, international and national guidelines as well as practical experience both in Korean and Canadian CANDU Nuclear Power Plants. The implementation of this program would provide a technical basis for calculations and records should be of acceptable quality and should meet overall radiation protection program objectives.
Search for the value of ?13 mixing angle is of importance in understanding the lepton flavor mixing matrix, and in motivating future experiments to probe CP violation in the lepton sector. Among the present experimental approaches, reactor experiment can provide a clean laboratory for the ?13-measurement. The Daya Bay experiment will start civil construction this year at Daya Bay, Guangdong, China. The goal of this experiment is to reach a sensitivity in sin2 2?13 of < 0.01 at 90% C.L. by precisely measuring the disappearance and spectral distortion of reactor electron anti-neutrinos with multiple identical detectors at different baselines. The talk will present the current status and prospects of the experiment.
A review of the performance of steam generator tubes in 116 water-cooled nuclear power reactors showed that tubes were plugged at 54 (46 percent) of the reactors. The number of tubes removed from service decreased from 4 692 (0.30 percent) in 1981 to 3 222 (0.20 percent) in 1982. The leading causes of tube failures were stress corrosion cracking from the primary side, stress corrosion cracking (or intergranular attack) from the secondary side and pitting corrosion. The lowest incidence of corrosion-induced defects from the secondary side occurred in reactors that have used only volatile treatment, with or without condensate demineralization.
Criticality was first achieved with the Fast Flux Test Facility (FFTF) a little more than 10 yr ago on February 9, 1980. Although the FFTF was designed and built primarily for testing fuels, materials, and components for the liquid-metal fast breeder reactor program, it has, over its first 10 yr of operation, provided valuable information in many other areas. This paper provides a summary of the contributions to the physics of liquid-metal reactors (LMRs) obtained from operation of and testing in the FFTF, with emphasis on some of the more significant and interesting accomplishments.
Precisely measuring $\\theta_{13}$ is one of the highest priority in neutrino oscillation study. Reactor experiments can cleanly determine $\\theta_{13}$. Past reactor neutrino experiments are reviewed and status of next precision $\\theta_{13}$ experiments are presented. Daya Bay is designed to measure $\\sin^22\\theta_{13}$ to better than 0.01 and Double Chooz and RENO are designed to measure it to 0.02-0.03. All are heading to full operation in 2010. Recent improvements in neutrino moment measurement are also briefed.
The reactor fuel cycle based on uranium is described. The various stages in the cycle include mining of uranium ores followed by crushing and grinding, leaching and purification of leach liquor by ion exchange resin process or solvent extraction process, refining of uranium concentrate (yellow cake) by digesting with HNO_3 and then solvent extracting uranyl nitrate with TBP, conversion of uranyl nitrate to uranium hexafluoride, production of uranium metal, uranium enrichment, fabrication of reactor fuel elements and reprocessing of the spent fuel. Chemical reactions wherever they are involved are explained. (M.G.B.).
A non-linear mathematical model of dynamics of horizontal steam generator for nuclear power unit with WWER type reactor is presented. To realize this model the GEMMA-120 simulation language for computer Odra-1204 has been used. Necessity of taking into account disposited thermal storage capacities along tubulation of a primary cycle is demonstrated. A number of lumped elements of reactor division against a required static accuracy of calculations has been determined. (author).
We study non-standard interactions (NSIs) at reactor neutrino experiments, and in particular, the mimicking effects on \\theta_13. We present generic formulas for oscillation probabilities including NSIs from sources and detectors. Instructive mappings between the fundamental leptonic mixing parameters and the effective leptonic mixing parameters are established. In addition, NSI corrections to the mixing angles \\theta_13 and \\theta_12 are discussed in detailed. Finally, we show that, even for a vanishing \\theta_13, an oscillation phenomenon may still be observed in future short baseline reactor neutrino experiments, such as Double Chooz and Daya Bay, due to the existences of NSIs.
A nonlinear dynamic transient analysis merging hand calculations and the NASTRAN structural analysis computer code was conducted for a Fast Flux Test Facility in-reactor test assembly during an extremely unlikely design basis accidental event which is considered a Hypothetical Core Disruptive Accident (HCDA). The finite element modeling of the problem took advantage of NASTRAN's versatility to create loads and nonlinear elements not previously found in NASTRAN's library. The structural criteria for the test assembly to withstand an HCDA stipulates that the test assembly and its spoolpiece shall remain integral with the reactor head such that missiles are not generated.
Norwegian authorities regard with some disquiet the possibility of a criticality accident in a ship propulsion reactor core at the Kola coast. Along this coast, in land storages, floating storages and in submarines taken out of service, the total number of spent fuel reactor cores amount to two hundred. The total Cs-137 radioactivity in spent ship propulsion reactor fuel at the Kola peninsula can be assessed to 600,000 TBq. A worst case release may amount to more than 5,000 TBq Cs-137, a quantity which under unfavourable conditions might cause serious contamination locally and even across the border to Norway.
This report presents a general investigation of the transport requirements associated with the construction and operation of conceptual fusion reactors. Projections of amounts of construction and operating materials requiring transportation are presented for several proposed designs. The material to be shipped is described along with the shipping containers that might be used, the transport modes and the expected impact of transporting these materials. Transportation of both radioactive and nonradioactive materials will be required. Most of these materials are routinely shipped by the transportation industry. Transportation requirements of a representative fusion reactor are also compared with Liquid Metal Fast Breeder Reactor (LMFBR) requirements.
The Fast Flux Test Facility (FFTF) is a 400 MWt sodium-cooled fast reactor operated by Westinghouse Hanford Company for the US Department of Energy to conduct fuels and materials testing in support of the US Liquid Metal Fast Breeder Reactor programme. Early in 1982, the FFTF began its first 100 day irradiation cycle. Since that time the plant has operated very well, achieving a cycle capacity factor of 94 per cent in the most recent irradiation cycle. The authors describe the results achieved in the first three cycles of operation and carrying through to the fourth reactor cycle which began in January 1984. (author).
The report presents a summary of the work of the Department of Nuclear Safety Research and Nuclear Facilities in 1995. The department`s research and development activities are organized in three research programmes: Radiation Protection, Reactor Safety, and Radioanalytical Chemistry. The nuclear facilities operated by the department include the Research Reactor DR3, the Isotope Laboratory, the Waste Treatment Plant, and the Educational Reactor DR1. Lists of staff and publications are included together with a summary of the staff`s participation in national and international committees. (au) 5 tabs., 21 ills.
The Daya Bay Reactor Anti-Neutrino Experiment is a neutrino oscillation experiment designed to observe and measure the neutrino mixing angle ?13. The sensitivity goal is 0.01 in sin 22?13 at the 90% confidence level, a significant improvement over the current limit. This will be accomplished by measuring the relative rates and energy spectra of reactor electron antineutrinos with multiple detectors positioned at different baselines. Civil construction is currently under-way as detector designs and planning near completion. Commissioning activities should be completed by the end of 2010, followed by a three-year run.
The paper provides a brief description of the fuel characterization for Fast Breeder Test Reactor (FBTR) and Prototype Fast Breeder Reactor (PFBR). The development and characterization of mechanical properties of Alloy D9 clad and wrapper tubes are discussed. The problems associated with fusion welding of Alloy D9 are outlined. Non-destructive characterization of cladding tubes by optimum encircling eddy current probes, on-line and off-line neural network methods is presented. Both the on-line and off-line neural network methods could readily detect and size defects specified by the designers
Existing applications of Alloy 800 are summarized, with particular reference to its use in various types of reactor. The need for a co-ordinated research and development programme is stressed, and the variables to be explored are outlined. The papers relating to the problem of corrosion and cracking in water and steam are considered. the strength and ductility of Alloy 800 is considered. Finally, sections of the summary deal with the use of Alloy 800 for (a) sodium cooled fast reactor boiler tubes; (b) the high temperature gas cooled reactor; and (c) PWR steam generator tubes. (U.K.).
Abstract It is now widely accepted that remembering the past and imagining the future rely on a number of shared processes and recruit a similar set of brain regions. However, memory and future thinking place different demands on a range of processes. For instance, although remembering should lead to early associative retrieval of event details, event construction may be slower for future events, for which details from different memories are combined. In order to shed light on the question of how the brain distinguishes between memories and future thoughts, we investigated the differences in the electrophysiological correlates of the vivid elaboration of future and past events. In the slow cortical potentials of 24 healthy human participants, differences during early elaboration were obser...
Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, we implemented an application where users can upload data and immediately navigate through its ad hoc dimensions. To support social networking, views can be easily shared and embedded in other Web sites. Algorithmically, our tag-cloud views are approximate range top-k queries over spontaneous data cubes. We present experimental evidence that iceberg cuboids provide adequate online approximations. We benchmark several browser-oblivious tag-cloud layout optimizations.
For almost 150 years, the two monotypic genera Trochodendron and Tetracentron (Trochodendraceae) have been considered to share an unusual and primitive feature in angiosperms - the lack of vessels in their wood. Therefore, they have been classified in a basal position in the angiosperms. Our observations by light microscopy, low-vacuum environmental scanning electron microscopy (ESEM) and high-vacuum scanning electron microscopy (SEM) both in fresh and FAA-fixed materials consistently showed the presence of tracheary elements differentiated into two types in both genera. In Trochodendron, the tracheary elements can be divided into perforate vessel elements and imperforate fiber-tracheids and tracheids. The vessel elements show end and lateral walls. The pits on the end walls are elongate- ...
Climate change represents the largest social dilemma humans have ever faced, where individual actors maximise their personal gain by emitting greenhouse gases into the atmosphere even though this is detrimental to the collective global good. Cooperation on a global scale is urgently required if we are to overcome this problem. However, this is difficult to achieve because cooperators pay the cost of reducing emissions while any benefits are shared between cooperators and free-riders alike. In a risk-free, rational world cooperative behaviour can be promoted through mechanisms that increase the benefit of cooperating relative to free-riding, such as rewards or sanctions. In reality, however, outcomes are seldom certain and humans rarely behave rationally when confronted with risky prospects...
Our investigation concerns the class of Josephson-like systems, sharing the same nonlinear Hamiltonian. Among the latter a Josephson junction with an external biasing circuit is considered. We diagonalize the fully nonlinear Hamiltonian (in the superconductive regime of the junction) in the Fock space of the TBHA (two-boson Heisenberg algebra) and prove that such algebra leads quite naturally to the theoretical realization of codewords and logical operators: the codewords are defined as the even and odd coherent states of the TBHA, while the logical operators are expressed in terms of operators in the same algebra. Our theoretical construction corresponds to a continuous variable quantum computation scheme; the continuous variables are identified in terms of the physical operators of the junction. The link between this scheme and the technique of fermionization of bosonic systems is also discussed.
Two days of hearings on Titles V and X of the Water Resources Development Act of 1983 brought comments from representatives of several states, farm and transport industries, environmental groups, and concerned taxpayers. Title V requires the collection of new funds from users beyond a ceiling set for annual spending on water projects, while Title X proposes a cost-sharing partnership for certain navigation projects. Witnesses were requested to confine their comments to constructive alternatives to the proposed legislation. Additional material on the deep river study and statements submitted for the record follow the testimony of 28 witnesses.
Local communities in southern Africa derive many benefits from marula [Sclerocarya birrea (A. Rich.) Hochst. subsp. caffra (Sond.) Kokwaro]. These include the contribution of this species towards health, nutrition, food security and conservation by sharing local skills and knowledge related to it. Marula fruits can be eaten fresh, squeezed to make juice, brewed in traditional beer or used to make jam and jelly. The kernels are also edible and can be pressed to extract oil for cooking and cosmetics, i.e., for skin and hair application. The bark, roots, seeds and leaves are exploited for traditional medicinal purposes. Marula has acquired significant commercial value since its fruits and other products have entered local, regional and international trade in southern Africa. To diversify frui...
Previous family and twin studies have indicated that Graves' disease has a heritable component. Family studies have also shown that some autoimmune disease cluster in families and genetic studies have been able to show shared susceptibility genes. In the present nation-wide study we describe familial risk for Graves' disease among parents and offspring, singleton siblings, twins and spouses with regard to age of onset, gender and number and type of affected family members. Additionally familial association of Graves' disease with any of 33 other autoimmune and related conditions was analyzed. The Swedish Multigeneration Register on 0-75-year-old subjects was linked to the Hospital Discharge Register from years 1987-2007. Standardized incidence ratios (SIRs) were calculated for individuals ...
This paper is about two arrangements of hyperplanes. The first --- the Shi arrangement --- was introduced by Jian-Yi Shi to describe the Kazhdan-Lusztig cells in the affine Weyl group of type $A$. The second --- the Ish arrangement --- was recently defined by the first author who used the two arrangements together to give a new interpretation of the $q,t$-Catalan numbers of Garsia and Haiman. In the present paper we will define a mysterious "combinatorial symmetry" between the two arrangements and show that this symmetry preserves a great deal of information. For example, the Shi and Ish arrangements share the same characteristic polynomial, the same numbers of regions, bounded regions, dominant regions, regions with $c$ "ceilings" and $d$ "degrees of freedom", etc. Moreover, all of these results hold in the greater generality of "deleted" Shi and Ish arrangements corresponding to an arbitrary subgraph of the complete graph. Our proofs are based on nice ...
Phenomenological sociology was founded at the beginning of 1930s by Alfred Schutz. His mundane phenomenology sought to combine impulses drawn from Husserl's transcendental phenomenology and Weber's action theory. It was made famous at the turn of 1960s and 1970s by Garfinkel's ethnomethodology and Berger & Luckmann's social constructionism. This paper deals with the notable accomplishments of Schutz and his followers and then proceeds to a shared shortcoming, which is that the phenomenological approach is unable to understand meaning in any other way but as actors's knowledge. Therefore, phenomenological sociologists are forced to describe the actor's interpretations of meaning as transparent to the actor him/herself, even if they sometimes make heroic attempts to escape the limitations of...
In the context of the LHC computing grid (LCG) project, the applications area develops and maintains that part of the physics applications software and associated infrastructure that is shared among the LHC experiments. The "physicist interface" (PI) project of the LCG application area encompasses the interfaces and tools by which physicists will directly use the software, providing implementations based on agreed standards like the analysis systems subsystem (AIDA) interfaces for data analysis. In collaboration with users from the experiments, work has started with implementing the AIDA interfaces for (binned and unbinned) histogramming, fitting and minimization as well as manipulation of tuples. These implementations have been developed by re-using existing packages either directly or by using a (thin) layer of wrappers. In addition, bindings of these interfaces to the Python interpreted language have been done using the dictionary subsystem of the LCG ...
In the context of the LHC Computing Grid (LCG) project, the Applications Area develops and maintains that part of the physics applications software and associated infrastructure that is shared among the LHC experiments. The "Physicist Interface" (PI) project of the LCG Application Area encompasses the interfaces and tools by which physicists will directly use the software, providing implementations based on agreed standards like the AIDA interfaces for data analysis. In collaboration with users from the experiments, work has started with implementing the AIDA interfaces for (binned and unbinned) histogramming, fitting and minimization as well as manipulation of tuples. These implementations have been developed by re-using existing packages either directly or by using a (thin) layer of wrappers. In addition, bindings of these interfaces to the Python interpreted language have been done using the dictionary subsystem of the LCG-AA/SEAL project. The actual status and ...
The Low Power and Shutdown (LPSD) PRA (Probabilistic Risk Assessment) Standard (ANS-58.22) is currently being drafted by a Writing Group under the auspices of the Risk Informed Standards Committee of the American Nuclear Society (ANS). The Writing Group includes representatives from nuclear utilities, US Nuclear Regulatory Commission (NRC), national laboratories, universities, and consultants with substantial experience producing LPSD PRAs. This draft standard is scheduled to be released for public comment in the second quarter of 2004, with publication by the end of 2004. The LPSD PRA Standard is based on a mature technology that shares many requirements with full power PRAs. It will provide specific methods and criteria whereby PRAs of appropriate quality and scope can be used in the conduct of plant decision-making and other activities, including addressing NRC requirements. This paper presents the current status of this standard.
Summary 1. In the Greater Yellowstone Ecosystem, bison Bison bison and elk Cervus canadensis nelsoni act as hosts for Brucella abortus. The presence of B. abortus within wildlife populations is an important conservation issue because of the risk of brucellosis transmission from wildlife to cattle. 2. We investigated conditions facilitating contact between bison (40-60% seroprevalence) and elk on a shared winter range in the Madison headwaters area of Yellowstone National Park. We evaluated the effects of snow pack, season, elk and bison population sizes, and wolf Canis lupus predation risk on the degree of spatial overlap between bison and elk from 1991 to 2006. 3. Sixty-eight per cent of 10 093 independent elk observations occurred within the known bison wintering range, 29% occurred with...
This is a thought piece on data-intensive science requirements for databases and science centers. It argues that peta-scale datasets will be housed by science centers that provide substantial storage and processing for scientists who access the data via smart notebooks. Next-generation science instruments and simulations will generate these peta-scale datasets. The need to publish and share data and the need for generic analysis and visualization tools will finally create a convergence on common metadata standards. Database systems will be judged by their support of these metadata standards and by their ability to manage and access peta-scale datasets. The procedural stream-of-bytes-file-centric approach to data analysis is both too cumbersome and too serial for such large datasets. Non-procedural query and analysis of schematized self-describing data is both easier to use and allows much more parallelism.
The ALICE experimental area management team faces various challenges when it comes to sharing scarce resources, indispensable to any efficient installation in a category one worksite. Space, cranes, jigs, and personnel with key competences have to be carefully allocated to activities so as to avoid slowing down work progress. To this intent, a resource loaded planning has been developed that allows highlighting coactivities and prioritizing critical tasks. It uses the built-in capabilities of Microsoft Project. The use of this scheduling tool leads to a more efficient use of time and a safer work environment. The installation sequence resulting from this schedule is presented in this paper. The first part of the sequence focuses on the revision of the coils in the SX2 building. The dipole has then to be installed in the RB26 side of the UX25 cavern. This complex and resource intensive activity has to be performed in parallel with the services installation inside ...
Wind power is a maturing technology that in a number of countries is likely to contribute a major share to fully renewable energy systems. Denmark has a comparably long history of wind power development and is planning to continue expanding the existing capacity. If a large-scale penetration of wind power is to be achieved, an integrated framework is needed that can respond to the associated challenges. This paper argues for adopting an integrated macro perspective when evaluating and building frameworks to support wind power development. This macro perspective is applied to the case of Denmark, and more specifically to concrete wind power projects in the region of Northern Jutland. The results suggest although certain elements in the legislation have been improved, the feasibility of wind power projects cannot be guaranteed, and there is a tendency to exclude smaller turbines from the development.
The return on investment for the chemical/petrochemical industrial is getting worse in comparison with other industrials. For example, in the last five years, the NASDAQ index has increased its value from 770 to 2200 (314%). Especially, in the areas of internet business, certain stock values has increased by five time in less than 3 years. However, the average changes in stock values for the chemical/petrochemical/oil industrials are between -50% to +230%. This is far too small for the expectation of today`s investors. Consequently, many companies diversified to pharmaceutical business where the profit margins are higher. Lately there have been many mergers for a better share of capitals and manpower, hence improving the profit margins. However, what is the bottom-line problems? What role can process integration play to better our future? (au)
Personal health information management (PHIM) refers to activities that support consumers' access, integration, organization, and use of their personal health information. We investigated PHIM in the health consumer population using a focus group and participatory design. In collaboration with health consumers, we identified PHIM activities and explored the design of new supportive technology. Our findings describe prominent PHIM activities such as monitoring and assessing health, as well as health-related decision making, planning, and action. We describe design principles our participants used during the participatory design of a PHIM tool. These include individual control, sharing, integration, security and flexibility. These findings provide new insights into emerging ideas in consumer health informatics research and technology design. Understanding health consumers' PHIM needs is an important step in creating technology to support these needs. PMID:17238322
Multi-fiber WDM networks are becoming the major telecommunication platforms for transmitting exponentially increasing data traffic. While today's networks are mainly providing circuit-switched connections, optical packet-switching technologies have been investigated for years, aiming at achieving more efficient utilizations of network resources. In this paper, we have evaluated, for the first time, the packet-loss performance of multi-fiber optical packet switches (MOPS). Our main contributions are threefold. Firstly, we have proposed simple and accurate analytical models for analyzing packet-loss performance of (i) the most fundamental MOPS configuration, (ii) MOPS equipped with fiber delay lines (FDLs) and (iii) shared wavelength converters (SWCs). Secondly, we have shown that the MOPS n...
This issue of Carbon Market Perspectives on 'Pathways for implementing REDD+: Experience from carbon markets and communities' discusses the role of carbon markets in scaling up investments for REDD+ in developing countries. Nine articles authored by experienced negotiators on REDD+, carbon market actors, project developers and other leading experts share experiences and make suggestions on the key elements of a future international REDD+ regime: Architecture and underlying principles, measuring, reporting and verification (MRV), private-sector involvement, the rights of indigenous people and local communities, biodiversity conservation and environmental integrity. The articles are grouped under three main topics: the lessons of existing REDD+ projects; the future REDD+ regime and the role of carbon markets; and experiences and ideas about the involvement of indigenous people and local communities. (LN)
One of the most common types of functions in mathematics, physics, and engineering is a sum of products, sometimes called a partition function. After "normalization," a sum of products has a natural graphical representation, called a normal factor graph (NFG), in which vertices represent factors, edges represent internal variables, and half-edges represent the external variables of the partition function. In physics, so-called trace diagrams share similar features. We believe that the conceptual framework of representing sums of products as partition functions of NFGs is an important and intuitive paradigm that, surprisingly, does not seem to have been introduced explicitly in the previous factor graph literature. Of particular interest are NFG modifications that leave the partition function invariant. A simple subclass of such NFG modifications offers a unifying view of the Fourier transform, tree-based reparameterization, loop calculus, and the Legendre ...
China's fast-growing online consumer-to-consumer (C2C) market merits widespread research efforts. However, it has so far received little research attention. In this exploratory study, we chose Taobao - a leading online C2C auction company in China with more than 70% of market shares - as our research context. We focus on the general market structure of Taobao in terms of three factors: market distribution, market growth, and market concentration. Based on these factors, we reveal the differences between Taobao and eBay. In our preliminary data analyses, we adopt total online reputation scores to measure the transaction volumes of online sellers. We also propose the sample-based Herfindal-Hirschman Index as a measure in the comparison of concentration levels between the two markets and at d...
Currently many service providers offer their services on a private and proprietary hard- and software infrastructure. These infrastructures often share many similarities. Hence we believe a generic service management architecture, that allows service providers to offer a large array of different services on a single infrastructure or multiple providers to offer their services cooperatively, would provide many advantages over current silo-based approaches. Additionally, by allowing the distributed service management components to cooperate in a peer-to-peer overlay network, scalability and resilience of the system could be greatly improved. In this paper we propose an optimal algorithm, based on an integer linear programming (ILP) formulation, and several heuristics to support such a generi...
Availability of a natural gas-powered van that meets California`s ultra low emission vehicle requirements and has a 300-km range was reported. A similar van with an electric system giving a range of 240 km was also within sight. Regarding the limitations of electric batteries it was suggested that a super capacitor may allow systems to achieve higher energy densities; a refuelable zinc-air battery could be considered for vehicle use. While the prospect for emissions improvement of gasoline vehicles has clearly improved in recent years, the relative costs of infrastructure, vehicle and fuel for the the alternative fuels compared with gasoline demonstrate the difficulty the alternative fuels have in taking market share from gasoline. For the next decade, gasoline, propane and CNG are expected to be the dominant fuels for vehicles. After that, the leading fuel will be the one that has been most extensively researched and developed during the decade. 17 refs.
Two constructions due to Dr\\'apal produce a group by modifying exactly one quarter of the Cayley table of another group. We present these constructions in a compact way, and generalize them to Moufang loops, using loop extensions. Both constructions preserve associators, the associator subloop, and the nucleus. We conjecture that two Moufang 2-loops of finite order $n$ with equivalent associator can be connected by a series of constructions similar to ours, and offer empirical evidence that this is so for $n=16$, 24, 32; the only interesting cases with $n\\le 32$. We further investigate the way the constructions affect code loops and loops of type $M(G, 2)$. The paper closes with several conjectures and research questions concerning the distance of Moufang loops, classification of small Moufang loops, and generalizations of the two constructions.
Research shows that comment spamming (comments which are unsolicited, unrelated, abusive, hateful, commercial advertisements etc) in online discussion forums has become a common phenomenon in Web 2.0 applications and there is a strong need to counter or combat comment spamming. We present a method to automatically detect comment spammer in YouTube (largest and a popular video sharing website) forums. The proposed technique is based on mining comment activity log of a user and extracting patterns (such as time interval between subsequent comments, presence of exactly same comment across multiple unrelated videos) indicating spam behavior. We perform empirical analysis on data crawled from YouTube and demonstrate that the proposed method is effective for the task of comment spammer detection.
Episodic memory can be regarded as part of a more general system, unique to humans, for mental time travel, and the construction of future episodes. This allows more detailed planning than is afforded by the more general mechanisms of instinct, learning, and semantic memory. To be useful, episodic memory need not provide a complete or even a faithful record of past events, and may even be part of a process whereby we construct fictional accounts. The properties of language are aptly designed for the communication and sharing of episodes, and for the telling of stories; these properties include symbolic representation of the elements of real-world events, time markers, and combinatorial rules. Language and mental time travel probably co-evolved during the Pleistocene, when brain size increased dramatically. PMID:18641975
The purpose of this paper is to communicate how new and established management techniques are applied to environmental restoration projects at the Savannah River Site. Specifically, the paper discusses application of four (4) management approaches: Total Quality Principles; Task Team Structure; Cost Time Management; SAFER (Streamlined Approach for Environmental Restoration). The objective is to share Savannah River Site experience and document case studies where certain approaches have enhanced projects at hand. Each management approach is demonstrated by its project application and impact on performance. The visibility given the project is discussed to emphasize communications as avenues for public information, technical exchange, and employee motivation.
The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. The Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently-operating low-level radioactive waste facilities. This report contains information synthesizing the accomplishments of the Forum, as well as any new advances that have been made in the management of low-level radioactive wastes.
The determination of Li and proton-capture element abundances in globular cluster (GC) giants allows us to constrain several key questions on the multiple population scenarios in GCs, from formation and early evolution to pollution and dilution mechanisms. In this Letter, we present our results on Li abundances for a large sample of giants in the intermediate-metallicity GC NGC 6121 (M4), for which Na and O have been already determined by Marino et al. The stars analyzed are both below and above the red giant branch bump luminosity. We found that the first and second generation stars share the same Li content, suggesting that a Li production must have occurred. This provides strong observational evidence supporting the scenario in which asymptotic giant branch stars are GC polluters.
KEPCO (Korean Electric Power Corp.) with the support of AECL and other Korean and Canadian subcontractors has created a strong multi-company team to execute design and construction of the Wolsung-2 CANDU 6 power plant. Key concepts of the project team are: 1. KEPCO is the project manager, and AECL is the major engineering and supply contractor; 2. Significant participation by Korean companies in design work in Canada and Korea; 3. Significant manufacturing in both Canada and Korea; 4. Construction by Korean contractors. Key concepts of the Wolsung 2 design are: 1. Evolutionary improvement of the Wolsung-1 plant which balances proven technology and necessary design improvements including current codes and standards. 2. Sharing some structures with the Wolsung-1 plant. This paper describes the successful establishment and operation of the complex project interfaces along with the current project status and plans.
Cache locking technique is often utilized to guarantee a tighter prediction of Worst-Case Execution Time (WCET) which is one of the most important performance metrics for embedded systems. However, in Multi-Processor Systems-on-Chip (MPSoC) systems with multi-tasks, Level 2 (L2) cache is often shared among different tasks and cores, which leads to extended unpredictability of cache. Task assignment has inherent relevancy for cache behavior, while cache behavior also affects the efficiency of task assignment. Task assignment and cache behavior have dramatic influences on the overall WCET of MPSoC. This paper proposes joint task assignment and cache partitioning techniques to minimize the overall WCET for MPSoC systems. Cache locking is applied to each task to guarantee a precise WCET. We pr...
The present conference on lens design encompasses physical and geometrical optics, diffractive optics, the optimization of optical design, software packages, ray tracing, the use of artificial intelligence, the achromatization of materials, zoom optics, microoptics and GRIN lenses, and IR lens design. Specific issues addressed include diffraction-performance calculations in lens design, the optimization of the optical transfer function, a rank-down method for automatic lens design, applications of quadric surfaces, the correction of aberrations by using HOEs in UV and visible imaging systems, and an all-refractive telescope for intersatellite communications. Also addressed are automation techniques for optics manufacturing, all-reflective phased-array imaging telescopes, the thermal aberration analysis of a Nd:YAG laser, the analysis of illumination systems, athermalized FLIR optics, and the design of array systems using shared symmetry.
An increasing share of natural gas supplies distributed to residential appliances in the U.S. may come from liquefied natural gas (LNG) imports. The imported gas will be of a higher Wobbe number than domestic gas, and there is concern that it could produce more pollutant emissions at the point of use. This report will review recently undertaken studies, some of which have observed substantial effects on various appliances when operated on different mixtures of imported LNG. While we will summarize findings of major studies, we will not try to characterize broad effects of LNG, but describe how different components of the appliance itself will be affected by imported LNG. This paper considers how the operation of each major component of the gas appliances may be impacted by a switch to LNG, and how this local impact may affect overall safety, performance and pollutant emissions.
Co-combustion of chicken litter with coal was performed in a laboratory-scale fluidized bed combustor to investigate the effect of chicken litter addition on the partitioning behavior of mercury. Gaseous total and elemental mercury concentrations in the flue gas were measured online, and ash was analyzed for particle-bound mercury along with other elemental and surface properties. The mercury mass balance was between 85 and 105%. The experimental results show that co-combustion of chicken litter decreases the amount of elemental and total mercury in the gas phase. Mercury content in fly ash increases with an increasing chicken litter share. 22 refs., 6 figs., 5 tabs.
An initial public offering (IPO) can often provide a powerful stimulus to private companies seeking to pursue an acquisition-driven growth strategy. Based on a comprehensive analysis of U.S. IPOs, the authors show that newly public companies are prolific acquirers. Over 30% of companies conducting an IPO make at least one acquisition in their IPO year, and the typical IPO firm makes about four acquisitions during its first five years as a public company. IPOs facilitate M&A not only by providing infusions of capital but also by creating ongoing access to equity and debt markets for cash-financed deals. In addition, IPOs create an acquisition currency that can prove valuable in stock-financed deals when the shares are attractively priced. The authors also argue that IPOs improve the ability...
To discuss and share knowledge around advances in the care of patients with thrombotic disorders, the Third International Symposium of Thrombosis and Anticoagulation was held in S?o Paulo, Brazil, from October 14?16, 2010. This scientific program was developed by clinicians for clinicians, and was promoted by four major clinical research institutes: the Brazilian Clinical Research Institute, the Duke Clinical Research Institute of the Duke University School of Medicine, the Canadian VIGOUR Centre, and the Uppsala Clinical Research Center. Comprising 3?days of academic presentations and open discussion, the symposium had as its primary goal to educate, motivate, and inspire internists, cardiologists, hematologists, and other physicians by convening national and international visionaries, th...
Entanglement swapping allows to establish entanglement between independent particles that never have interacted nor share a common past. This feature makes it an integral constituent of quantum repeaters and a promising tool for future tests of the foundations of quantum physics. Here, we demonstrate entanglement swapping with time-synchronized independent sources with a fidelity high enough to violate a Clauser-Horne-Shimony-Holt (CHSH) inequality by more than four standard deviations. The fact that both entangled photon pairs are created by fully independent laser sources, which are only electronically connected, ensures that this technique is suitable for future long-distance entanglement swapping and quantum-repeater experiments.
Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the polymorphs'' of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes worm holes'' in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100[degrees]C lock in the mechanical twins.
Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the ``polymorphs`` of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes ``worm holes`` in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100{degrees}C lock in the mechanical twins.
Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot ...
In cluster-based routing protocol (CBRP), two-level hierarchical structure is successfully used to reduce over-flooding in wireless Ad Hoc networks. As it is vulnerable to a single point of failure, we propose a new adaptive distributed threshold scheme to replace the cluster head by a group of cluster heads within each cluster, called COUNCIL, and distribute the service of single cluster head to multiple cluster heads using (k,n) threshold secret sharing scheme. An Ad Hoc network formed by COUNCIL based clusters can work correctly when the number of compromised cluster heads is smaller than k. To implement this adaptive threshold scheme in wireless Ad Hoc Networks, membership of the clusters should be defined in an adaptive way. In this paper, we mainly discuss our algorithm for forming COUNCIL based clusters using the concept of dominating set from graph theory.
The use of natural gas in China is still relatively immature, as gas production only supplies a low percentage of the domestic energy system. In contrast, Chinese economy mainly relies on coal with a 67% share of the total primary energy supply. The environmental impact from this high coal dependence is significant and planners have sought for cleaner energy sources. Natural gas is both cleaner and generally more efficient than coal and gas consumption is rising quickly due to these facts. The growth tendency indicates that natural gas will become an important substitution for coal in some parts of the Chinese primary energy consumption. To quantify this tendency, this paper uses a system dynamics model to create a possible outlook. The results show that the gas consumption in China will c...
Levin KA, Jones CM, Wight C, Valentine C, Topping GVA, Naysmith R. Fluoride rinsing and dental health inequalities in 11-year-old children: an evaluation of a supervised school-based fluoride rinsing programme in Edinburgh. Community Dent Oral Epidemiol 2009; 37: 19-26. Copyright 2009 The Authors. Journal compilation Copyright 2009 John Wiley &Sons A/S Abstract - Objectives: Previous studies have shown that fluoride mouthrinsing programmes are effective in reducing caries among children and adolescents. National surveys of child dental health in the UK confirm that there is variation in oral health. In particular, children of low socioeconomic status in Scotland have a disproportionately high share of dental disease. This study aimed to evaluate an existing school-based fluoride mouthrinsi...
Abstract The benthic marine worm Xenoturbella is frequently contaminated with molluscan DNA, which had earlier caused confusion resulting in a suggested bivalve relationship. In order to find the source of the contaminant, we have used molluscan sequences derived from Xenoturbella and compared them to barcodes obtained from several individuals of the nonmicroscopic molluscs sharing the same environment as Xenoturbella. Using cytochrome oxidase 1, we found the contaminating sequences to be 98% similar to the bivalve Ennucula tenuis. Using the highly variable D1-D2 region of the large ribosomal subunit in Xenoturbella, we found three distinct species of contaminating molluscs, one of which is 99% similar to the bivalve Abra nitida, one of the most abundant bivalves in the Gullmarsfjord where...
Entanglement is the essential quantum resource for a potential speed-up of information processing, as well as for sophisticated quantum communication. Quantum information networks will be required to convey information from one place to another, by using entangled light beams. Many physical systems are under consideration as building blocks, with different merits and faults, so that hybrid systems are likely to be developed. Here we present an important tool for connecting systems that share no common resonance frequencies: we demonstrate the first direct generation of entanglement among more than two bright beams of light, all of different wavelengths (532.251 nm, 1062.102 nm, and 1066.915 nm). We also observe, for the first time, disentanglement for finite channel losses, the continuous variable counterpart to entanglement sudden death.
In this paper we present a model and simulator for many clusters of heterogeneous PCs belonging to a local network. These clusters are assumed to be connected to each other through a global network and each cluster is managed via a local scheduler which is shared by many users. We validate our simulator by comparing the experimental and analytical results of a M/M/4 queuing system. These studies indicate that the simulator is consistent. Next, we do the comparison with a real batch system and we obtain an average error of 10.5\\% for the response time and 12\\% for the makespan. We conclude that the simulator is realistic and well describes the behaviour of a large-scale system. Thus we can study the scheduling of our system called \\dirac in a high throughput context. We justify our decentralized, adaptive and opportunistic approach in comparison to a centralized approach in such a context.
The LHCb experiment has chosen to use the SAM framework (Service Availability Monitoring Environment from EGEE-II) [1] make extensive tests of the LHCb environment at all the accessible grid resources. The availability and the proper definition of the local Computing and Storage Elements, user interfaces as well as the WLCG software environment are checked. The SAM framework is also used to pre-install the LHCb applications in the shared software area provided by each site. The deployment of the LHCb applications is based on a python tool developed inside the experiment. It is used for software management including incremental installation of interdependent packages and clean package removal. After the application software is installed a validation test of the whole MC chain is run. According to the results of the experiment specific SAM tests, the sites are (re)integrated into the LHCb production system managed by DIRAC [2]. The possibility of automated dynamic ...
Competitive bidding for ancillary services (A/S), in addition to bidding for energy, is increasingly recognized as an important part of electricity markets. In this paper, an LP-based approach is presented for solving the multi-product (i.e. energy and A/S products), multi-zone/area physical market dispatch problem. The approach can explicitly represent various constraints, such as reserve requirement constraints, network security limits, and sharing of constrained resource capacity (e.g. maximum unit generation) between energy and reserve. The joint dispatch method, which dispatches energy and reserve market concurrently, is extended to allow inter-zonal reserve trading in multi-zone competitive pool. Numerical examples are included to demonstrate the salient characteristics of the joint dispatch solution.
Virtualized infrastructure providers demand new methods to increase the accuracy of the accounting models used to charge their customers. Future data centers will be composed of many-core systems that will host a large number of virtual machines (VMs) each. While resource utilization accounting can be achieved with existing system tools, energy accounting is a complex task when per-VM granularity is the goal. In this paper, we propose a methodology that brings new opportunities to energy accounting by adding an unprecedented degree of accuracy on the per-VM measurements. We present a system - which leverages CPU and memory power models based in performance monitoring counters (PMCs) - to perform energy accounting in virtualized systems. The contribution of this paper is threefold. First, w...
IHI has developed a new Three-Dimensional Computer-Aided Design (3D-CAD) system to improve the design efficiency and quality of the steel structure of nuclear power plants. This system covers every design phase from the initial arrangement of structure to the production design sharing the same database. The system incorporates the design rules and professional expertise of designers, and enable easy and efficient design. The system can easily generate the three-dimensional data for structures, model data for stress analyses and composite arrangement data. The system has already been applied to several plants under construction and has achieved excellent results. The outline of the new CAD system is introduced. (author)
XMRV or xenotropic murine leukemia virus-related retrovirus, a recently discovered retrovirus, has been linked to both prostate cancer and chronic fatigue syndrome (CFS). Recently, the teams of Drs. Shyh-Ching Lo and Harvey Alter discovered the presence of sequences closely related to XMRV in the blood of 86.5% of patients with CFS [1]. These findings are important because since the initial discovery of XMRV in CFS, several studies have failed to find XMRV in specimens collected from CFS patients. While the current study also did not find XMRV in CFS, Lo et al. did detect sequences that belong to polytropic mouse endogenous retroviruses (PMV), which share considerable similarity with XMRV. Criteria for future studies that will help bring greater clarity to the issue of retroviral sequences in CFS are proposed below. PMID:21994623
Delayed Afterdepolarization in Sinoatrial Node. Introduction: Recent evidence indicates that spontaneous sarcoplasmic reticulum Ca release and Na-Ca exchanger current activation contribute to the sinoatrial node (SAN) automaticity. These findings suggest that SAN activity may share mechanisms that underlie both automaticity and triggered activity. The aim of this study is to test the hypothesis that spontaneous, nonvoltage gated, intracellular Ca (Cai) elevation may induce delayed afterdepolarization (DAD) in intact SAN during isoproterenol infusion. Methods and Results: We simultaneously mapped Cai and membrane potential in 31 isolated Langendorff-perfused canine right atriums (RA). Isoproterenol increased heart rate and late diastolic Cai elevation (LDCAE) of the superior SAN, leading to...
Explicitly defining virtual collections in a digital library can benefit both users and contributors. This paper outlines the costs and benefits for defining virtual collections and describes an implementation of collection-level metadata in two digital libraries. Our work suggests that component repositories of NSDL would profit by describing their collection, and sub-collections, using a schema such as the one we implemented. This would enable NSDL to provide a rich, cross-linked hierarchy of virtual collections. By sharing collection-level, rather than item-level, metadata, collections would provide detailed resource information, presumably keeping most of their viewership, while NSDL would provide a broad description of resources.
Effective teamwork among station work groups is essential for plant production and safety in all phases of plant operation. To achieve effective teamwork, all contributing work groups must have ongoing access to and share a common perspective on station work priorities, and recognize how their individual contributions fit with and support the contributions of other groups in support of the larger station goals. Achieving and maintaining this alignment in perspective across all workgroups can be a challenge in large organizations. This paper discusses the experience at Darlington in building and maintaining station teamwork among the station workgroups in support of day-to-day plant operations. The issues encountered and the resource impacts of specific teamwork supporting practices adopted are outlined. (author)
Increasingly, business projects are ephemeral. New Business Intelligence tools must support ad-lib data sources and quick perusal. Meanwhile, tag clouds are a popular community-driven visualization technique. Hence, we investigate tag-cloud views with support for OLAP operations such as roll-ups, slices, dices, clustering, and drill-downs. As a case study, we implemented an application where users can upload data and immediately navigate through its ad hoc dimensions. To support social networking, views can be easily shared and embedded in other Web sites. Algorithmically, our tag-cloud views are approximate range top-k queries over spontaneous data cubes. We present experimental evidence that iceberg cuboids provide adequate online approximations. We benchmark several browser-oblivious tag-cloud layout optimizations.
Today's building industry is promoting the use of renewable sources of energy to heat, cool, and illuminate commercial buildings. Societies such as the International Solar Energy Society sponsor conferences such as this one to share knowledge and experience in the area of solar energy. However, the technologies presented here assume a need for heating, cooling or illumination. A simple technique is presented for determining the actual heating, cooling, and lighting requirements for commercial buildings, and for reducing those requirements through proper building design before applying solar technologies. The energy nomographs are a graphic energy design tool developed to aid designers in making cost effective decisions about energy alternatives early in the design process. Reducing loads at this point can help reduce the expense of a passive or active solar system which is usually sized to meet a certain percentage of the annual loads.
Microbonding of the CMS Tracker Inner Barrel (TIB) and Tracker Inner Disks (TID) modules was shared among six different Italian Institutes. The organization devised and the infrastructure deployed to handle this task is illustrated. Microbonding specifications and procedures for the different types of TIB and TID modules are given. The tooling specially designed and developed for these types of modules is described. Experience of production is presented. Attained production rates are given. An analysis of the microbonding quality achieved is presented, based on bond strengths measured in sample bond pull tests as well as on rates of bonding failures. Italian Bonding Centers routinely performed well above minimum specifications and a very low global introduced failure rate, at the strip level, of only $\\sim$0.015 \\% is observed.
The necessity of supporting more and more social interaction (and not only the mere information sharing) in online environments is the disruptive force upon which phenomena ascribed to the Web2.0 paradigm continuously bud. People interacting in online socio-technical environments mould technology on their needs, seamlessly integrating it into their everyday life. MUVEs (Multi User Virtual Environments) are no exception and, in several cases, represent the new frontier in this field. In this work we analyze if and how MUVEs can be considered a mean for augmenting communities (and more in general people) life. We trace a framework of analysis based on four main observations, and through these lenses we look at Second Life and at several projects we are currently developing in that synthetic world.
Three complementary impact welding technologies are described in this paper. They are explosive welding, magnetic pulse welding, and laser impact welding, which have been used to provide metallurgical bonds between both similar and dissimilar metal pairs. They share the physical principle that general impact-driven welding can be carried out by oblique impact but are used at different length scales from meters to sub-millimeter. The different length scales require different kinds of systems to drive the process, and the scales themselves can give different weld morphologies. Metallographic analysis on cross-sections shows a wavy interface morphology which is likely the result of an instability associated with jetting, which scours the surfaces clean during impact. The normalized period and...
The difficulty in information communication and sharing are major problems for forest fire monitoring and early warning in China. As authors, we applied web service technology to a personal digital assistant (PDA) forest fire monitoring system and propose the framework of a monitoring system based on service-oriented architecture (SOA). At the same time, we describe the composition and function of web services from a server side and a client side. The method for developing a web service invocation engine on the PDA is introduced in detail. Finally, an example of a fire danger rating and fire weather services system are established, based on the Beijing Forest Fire Control System. The results show that the PDA forest fire monitoring system based on web services can effectively take advantag...
The author applies the GO methodology to reliability analysis of the offsite power supply system of Daya Bay NPP. The direct quantitative calculation formulas of the stable reliability target of the system with shared signals and the dynamic calculation formulas of the state probability for the unit with two states are derived. The method to solve the fault event sets of the system is also presented and all the fault event sets of the outer power supply system and their failure probability are obtained. The resumption reliability of the offsite power supply system after the stability failure of the power net is also calculated. The result shows that the GO methodology is very simple and useful in the stable and dynamic reliability analysis of the repairable system
An anthropologist shares with the ?SNA and data mining community? his own anthropological perspective framed during more than five decades of network thinking about a broad range of anthropological problems. For 50?years he has viewed all people, things, and ideas in dynamic relationships. That perspective is a network perspective and at the same time anthropological, combining ethnographic, historical, holistic, and comparative views. It is valuable and beneficial to the community of scholars who use network analysis to try to understand what is going on, what went on before, and what the future prospects are. As an anthropologist, his interest is more in the wholes generated by network linkages?systems of households, bands, lineages, communities, corporations, governments?than in the ind...
In this paper an efficient quantum secure direct communication (QSDC) scheme with authentication is presented, which is based on quantum entanglement and polarized single photons. The present protocol uses Einstein-Podolsky-Rosen (EPR) pairs and polarized single photons in batches. A particle of the EPR pairs is retained in the sender's station, and the other is transmitted forth and back between the sender and the receiver, similar to the ``ping-pong'' QSDC protocol. According to the shared information beforehand, these two kinds of quantum states are mixed and then transmitted via a quantum channel. The EPR pairs are used to transmit secret messages and the polarized single photons used for authentication and eavesdropping check. Consequently, because of the dual contributions of the polarized single photons, no classical information is needed. The intrinsic efficiency and total efficiency are both 1 in this scheme as almost all of the instances are useful and ...
Due to recent advancements in mobile computing and communication technologies, mobile ad hoc computational Grids are emerging as a new computing paradigm, enabling innovative applications through sharing of computing resources among mobile devices without any pre-existing network infrastructure. Energy-efficient resource allocation is one of the key issues in mobile ad hoc computational Grids due to limited battery life of mobile nodes. To reduce energy consumption, we propose a hybrid power-based resource allocation scheme for allocation of interdependent tasks to nodes within mobile ad hoc computational Grid. The basic idea is to exploit dependencies and task type, and allocate interdependent tasks to nodes accessible at minimum transmission power. We also propose a power-based algorithm...
Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man syndrome, a neurological autoimmune ...
Abstract in english Functional properties of soy proteins for food are closely related to the composition of their storage protein subunits. Using base excision sequence scanning (BESS), we show that the absence of the A4 peptide in the G4 glycinin subunit of the soybean (Glycine max L.) cultivar Enrei was caused by the same point mutation in the Gy4 gene as previously reported in the soybean cultivar Raiden. Although the genetic relationship between Raiden and Enrei is not known, the same p (more) oint mutation in their Gy4 genes may indicate that they probably share a related origin. The application of BESS to identify single nucleotide polymorphisms (SNPs) as co-dominant markers for marker-assisted selection (MAS) of a recessive null allele is also discussed.
In this paper, we propose a bid optimizer for sponsored keyword search auctions which leads to better retention of advertisers by yielding attractive utilities to the advertisers without decreasing the revenue to the search engine. The bid optimizer is positioned as a key value added tool the search engine provides to the advertisers. The proposed bid optimizer algorithm transforms the reported values of the advertisers for a keyword into a correlated bid profile using many ideas from cooperative game theory. The algorithm is based on a characteristic form game involving the search engine and the advertisers. Ideas from Nash bargaining theory are used in formulating the characteristic form game to provide for a fair share of surplus among the players involved. The algorithm then computes the nucleolus of the characteristic form game since we find that the nucleolus is an apt way of allocating the gains of cooperation among the search engine and the advertisers. The ...
Logic Programming languages and combinational circuit synthesis tools share a common "combinatorial search over logic formulae" background. This paper attempts to reconnect the two fields with a fresh look at Prolog encodings for the combinatorial objects involved in circuit synthesis. While benefiting from Prolog's fast unification algorithm and built-in backtracking mechanism, efficiency of our search algorithm is ensured by using parallel bitstring operations together with logic variable equality propagation, as a mapping mechanism from primary inputs to the leaves of candidate Leaf-DAGs implementing a combinational circuit specification. After an exhaustive expressiveness comparison of various minimal libraries, a surprising first-runner, Strict Boolean Inequality "<" together with constant function "1" also turns out to have small transistor-count implementations, competitive to NAND-only or NOR-only libraries. As a practical outcome, a more realistic ...
Reactor Power Measurement is an essential part of the Reactor Power Control Loop in PHWRs. None of the available power measuring sensor offers characteristics which allow their direct use in the Reactor Power Control Loop. Thermal power, which is considered as relatively accurate, suffers from measurement delays and is used only as reference. Neutronic power sensors like Ion Chambers and Self Powered Neutron Detectors (SPNDs) which sense instantaneous power suffer from inaccuracies. A technique is required which makes use of both types-reference power and instantaneous power to extract real power information from the signals. This paper describes techniques to calibrate (correct) neutronic power that with the thermal reference power signals. The paper also brings out limitation of the calibration technique. (author)
Tarapur Atomic Power Station unit-4 is first 540 MWe pressurized heavy water reactor. Heavy water is used as the coolant and moderator. With reactor operation tritium is formed by absorption of neutron by Deuterium atoms. Experience in the 220 MWe indicates that tritium is main contributor to the internal dose of radiation workers. Study on Tritium build up in Primary Heat Transport (PHT) and Moderator (MOD) system was carried out at the initial stage of the operation of the unit-3 and 4. This paper brings out tritium activity buildup in the PHT and MOD systems and its comparison with 220 MWe reactors. This paper helps in estimation of the internal dose contribution to the radiation workers at TAPS 3 and 4. (author)
Tarapur Atomic Power Station unit-4 is first 540 MWe pressurized heavy water reactor. Heavy water is used as the coolant and moderator. With reactor operation tritium is formed by absorption of neutron by deuterium atoms. Experience in the 220 MWe indicates that tritium is main contributor to the internal dose of radiation workers. Study on tritium build up in Primary Heat Transport (PHT) and Moderator (MOD) system was carried out at the initial stage of the operation of the unit-4. This paper brings out tritium activity buildup in the PHT and MOD systems and its comparison with 220 MWe reactors. This paper helps in estimation of the internal dose contribution to the radiation workers at TAPS 3 and 4. (author)
Two neutrino mixing angles have been measured, and much of the neutrino community is turning its attention to the unmeasured mixing angle, $\\quq$, whose best limit comes from the reactor neutrino experiment CHOOZ.\\cite{bib:chooz} New two detector reactor neutrino experiments are being planned, along with more ambitious accelerator experiments, to measure or further limit $\\quq$. Here I will overview how to measure $\\quq$ using reactor neutrinos, mention some experiments that were considered and are not going forward, and review the current status of four projects: Double Chooz in France, Daya Bay in China, RENO in South Korea and Angra in Brazil. Finally I will mention how the neutrino observer can gauge progress in these projects two years from now as we approach the times corresponding to early estimates for new results.
A total of 86 experimental fuel pins with various fuel, liner, and cladding candidate materials have been irradiated in the Experimental Breeder Reactor-II (EBR-II) and the Fast Flux Test Facility (FFTF) reactor as part of the SP-100 fuel pin irradiation testing program. Postirradiation examination results from these fuel pin are key in establishing performance correlations and demonstrating the lifetime and safety of the reactor fuel system. This paper provides a brief description of the in-reactor fuel pin tests and presents the most recent irradiation data on the performance of wrought rhenium (Re) liner material and high density UN fuel at goal burnup of 6 atom percent (at. %). It also provides an overview of the significant variety of other fuel/liner/cladding combinations which were irradiated as part of this program and which may be of interest to more advanced efforts.
A series of tests was recently completed at the 400-MW (thermal) Fast Flux Test Facility (FFTF) to further demonstrate the passive safety characteristics of liquid-metal-cooled fast reactors. Earlier FFTF testing of decay heat removal by sodium natural circulation was reported in 1981. The main purpose of the 1986 test series was to demonstrate passive reactor shutdown during a loss-of-flow event when several inherent shutdown devices called gas expansion modules (GEMs) were installed in the reactor. However, these tests also provide further data on the natural circulation performance of the primary system, in particular the reactor core, and thus add to the data base available for checking the validity of available analytical tools.
Radiological and environmental protection experience associated with the reactor cover gas processing system at the Fast Flux Test Facility (FFTF) has been excellent. Personnel radiation exposures received from operating and maintaining the reactor cover gas processing system have been very low, the system has remained free of radioactive particulate contamination through the first seven operating cycles (cesium contamination was detected at the end of Cycle 8A), and releases of radioactivity to the environment have been very low, well below environmental standards. This report discusses these three aspects of fast reactor cover gas purification over the first eight operating cycles of the FFTF (a duration of a little more than four years, from April 1982 through July 1986).
The ability of the /sup 252/Cf-source-driven neutron noise analysis method to measure subcriticality has been demonstrated in a variety of experimental configurations of fissile materials. Calculations for an approximately 4-m-dia configuration of light water reactor (LWR) fuel elements indicated the feasibility of measuring the subcriticality of large, loosely coupled arrays of LWR fuel elements by this same method. These analysis suggested application to the initial loading of both pressurized and boiling water reactors, zero-power testing of reactors (such as shutdown margin measurements after initial loading), light water reactor refueling, and safe storage of LWR spent fuel. In the fuel storage application, direct measurement of subcriticality in the actual fuel storage facilities provides the parameter which is directly related to criticality safety.
Development of Scientific Foundations of the Technology of the Metal Matrix Packing of Leaky Unreprocessible Spent Nuclear Fuel of Different Purpose Reactors for a Long-term Environmentally Safe Storage.
Theoretical models of the decontamination process are developed and combined with an existing model of "6"0Co production in CANDU PHW reactors to predict the effects of decontamination on long term "6"0Co build-up in reactor primary heat transport systems. The effects of decontamination interval, decontamination factor, and post-decontamination corrosion release are calculated. An optimum decontamination strategy for a Pickering G.S. type reactor is developed on the basis of a cost-benefit analysis. This study indicates that the optimum decontamination interval is approximately six years. This optimum interval is relatively insensitive to variations in the costs of personnel exposure, the cost of a decontamination, the decontamination factor, and the post-decontamination corrosion model used. (author).
The ORR operated at an average power level of 29.7 MW for 85.3% of the time during this period. The reactor was shut down on fifteen occasions, nine of which were unscheduled. Reactor downtime needed for refueling and checks was normal. The reactor remained available for operation 88.3% of the time. Special tests completed during the quarter included: (1) transfer of LEU fuel elements CLE-202 and NLE-201 from core positions B-9 and B-2 to core positions C-5 and C-6 for continued operation; and (2) calculation of maximum heat flux in LEU elements CLE-201 and NLE-202 in core positions A-2 and A-8. In-service inspections included inspections of ORR decay tank, primary heat exchanger No. 4, and the 24-in. strainer.
An emergency shutdown system for high-temperature gas-cooled pebble-bed reactors is proposed in addition to the common absorber rod shutdown system. This system is based on the strongly absorbing effect of small boronated graphite spheres (called KLAK), which trickle in case of emergency by gravity from the top reflector into the reactor core. The inner reflector of the Siemens-Argonaut reactor was substituted by an assembly of spherical Arbeitsgemeinschaft Versuchsreaktor fuel elements, and the shutdown effect was examined by installing well-defined KLAK nests inside this assembly. The purpose was to develop and prove a calculational procedure for determining criticality values for assemblies of large fuel spheres and small absorbing spheres.
Monte Carlo neutron transport methods can be used to verify the applicability of point kinetics for safety analysis of nuclear reactors. KENO-NR was used to obtain the transfer function of the Advanced Neutron Source reactor and the time delay between the core power production and the external detectors, a parameter of interest to the safety systems design. The good agreement between the Monte Carlo generated transfer function and the point kinetics transfer function validates that the uncommon ANS geometry does not preclude the use of point kinetics in the frequency range that was investigated. Various features of the power spectral densities also demonstrated the applicability of point kinetics. The time delay was obtained from the cross-power spectral density (CPSD) and is {approximately}15 ms. These analyses show that frequency analysis can be used experimentally to investigate the validity of the use of point kinetics models in critical ...
The results obtained from experimental investigations and mathematical simulation of horizontal steam generators are considered. Recommendations for continuing these works are given.
Purpose: To eliminate the water level deviation due to the recycling flowrate, as well as enable a stable control to a reference value even upon changes in the recycling flowrate caused by the variation in the opening degree of a minimum flow valve. Constitution: Reactor recycling system comprises a feedwater pump, a flowrate control valve, a reactor water level detector, and a minimum flow line and a minimum flow valve for preventing the overheating of the feedwater pump at a low flowrate. A flowrate compensator is further disposed, in which a recycling flowrate signal is subtracted from a pump flow rate signal and the result is fedback as a compensated pump flowrate signal. This enables the control system to operate at a rapid response for suppressing the effect of the recycling flowrate as external disturbance, whereby the water level in the reactor can be controlled stably to the reference level and the possibility ...
The document presented defines the plan to be used to coordinate the preparation, review, approval, and issuance of the operating procedure documents required to ensure safe and efficient operation of FFTF.
Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)
The development of an electrolytic reduction technology for spent fuels in the form of oxide is of essence to introduce LWR SFs to a pyroprocessing. In this research, the technology was investigated to scale a reactor up, the electrochemical behaviors of FPs were studied to understand the process and a reaction rate data by using U{sub 3}O{sub 8} was obtained with a bench scale reactor. In a scale of 20 kgHM/batch reactor, U{sub 3}O{sub 8} and Simfuel were successfully reduced into metals. Electrochemical characteristics of LiBr, LiI and Li{sub 2}Se were measured in a bench scale reactor and an electrolytic reduction cell was modeled by a computational tool.
Purpose: To secure the reactor operation safety by the provision of a fluid pressure detecting section for control rod driving fluid and a control rod interlock at the midway of the flow pass for supplying driving fluid to the control rod drives. Constitution: Between a driving line and a direction control valve are provided a pressure detecting portion, an alarm generating device, and a control rod inhibition interlock. The driving fluid from a driving fluid source is discharged by way of a pump and a manual valve into the reactor in which the control rods and reactor fuels are contained. In addition, when the direction control valve is switched and the control rods are inserted and extracted by the control rod drives, the pressure in the driving line is always detected by the pressure detection section, whereby if abnormal pressure is resulted, the alarm generating device is actuated to warn the abnormality and the ...
Progress reports are presented for the following two areas: catalytic cracking studies with water-wet silica-alumina catalysts; and Fischer-Tropsch reactor studies where similarities and differences between fixed bed and slurry type reactors are investigated and further experiments conducted to measure mass transfer coefficients and reaction kinetics which are to be used in a model slurry reactor. The following are some of the conclusions. (1) The premise that the presence of liquid water might increase catalytic cracking activity was found to be invalid. It was demonstrated that cracking can occur at previously unobserved low temperatures (though at low conversions) and that an anomaly exists in that one of the catalysts tested shows an entirely different cracking behavior and probably follows a different cracking mechanism. (2) the diameter of a fixed-bed Fischer-Tropsch reactor critically affected ...
In this work, long-term operation of a pilot scale mixed anaerobic reactor processing crude glycerol and rapeseed meal is discussed. These materials are generated as by-products of biodiesel production. Mixed reactor was operated under mesophilic conditions for the period of 654 days. Total cumulative production of biogas reached 379 m3 (at atmospheric pressure and ambient temperature). Maximum volumetric loading achieved during the operation was 2.17 kg m?3 d?1 for the crude glycerol dose of 2 L. When dosing crude glycerol as a single substrate, average specific production of biogas of 0.76 m3 per L of the g-phase was achieved. The lack of nutrients in the g-phase had to be compensated by an addition of ammonium nitrogen in the form of urea into the reactor. Long term processing of crude ...
The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this ...
Human errors have been reported as one of the most significant causes of major events in nuclear power plants (NPPs). For example, Kim and Park found that about 23% of the major events that occurred at NPPs in Republic of Korea from 1986 to 2006 were caused by human errors. For this reason, a detailed analysis on human errors is an important task for increasing the safety of NPPs. Kim and Choi?2 analyzed 100 human-related unplanned reactor trip events in the Republic of Korea from 1986 to 2006 to consider the type of human errors based on the simple path model for human-induced unplanned reactor trips developed by Kim and Park. In this paper, we will investigate and perform a detailed analysis of the data to identify human-related unplanned reactor trip trends