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Sample records for code ifa-432 aecl

  1. Status of the USNRC/PNL Halden test IFA-432

    International Nuclear Information System (INIS)

    Bradley, E.R.; Cunningham, M.E.; Lanning, D.D.; Williford, R.E.

    1980-01-01

    The NRC/PNL fuel assembly IFA-432 began irradiation in December 1975 and as of January 1980 had reached an assembly average burnup of 2120 GJ/kgU (24.5 GWd/MTM). The rods in this assembly are heavily instrumented and this has allowed a fairly thorough analysis of fuel behavior. The emphasis of the analysis has been to evaluate the observed changes in thermal/mechanical behavior. These changes are related to estimates of fuel density changes, fission gas release, and fuel cracking and relocation. The following conclusions have been reached concerning the irradiation of IFA-432. Based on analysis of steady-state and transient thermal data, the fuel in all rods is extensively cracked and relocated. Significant reductions in the effective fuel thermal conductivity have been deduced from the analysis of the transient thermal data

  2. Irradiation history and final postirradiation data for IFA-432

    International Nuclear Information System (INIS)

    Lanning, D.D.

    1986-11-01

    The irradiation history and final postirradiation examination (PIE) results are presented for the Halden fuel assembly IFA-432. In particular, the three instrumented rods (Rods 2, 3, and 5) that continued to the highest burnup (46 MWd/kgM) are emphasized. The long survival rate of the fuel instrumentation allowed a continuous record to be kept of linear heat generation rate and fuel temperatures throughout the operating history of the asembly. Fission gas release was estimated based on a combination of gas retention and ceramographic data. The PIE data show that the postirradiation condition of the rods is qualitatively consistent with the power/temperature histories experienced. Fission gas release estimates are: Rod 2 (380 μm as-fabricated gap), 20-40%; Rod 5 (230 μm as-fabricated gap), 20-40%; and Rod 3 (76 μm as-fabricated gap), 0-20%

  3. Data report for the NRC/PNL Halden Assembly IFA-432

    International Nuclear Information System (INIS)

    Hann, C.R.; Bradley, E.R.; Cunningham, M.E.; Lanning, D.D.; Marshall, R.K.; Williford, R.E.

    1978-08-01

    The report presents the in-reactor data collected from the NRC/PNL Halden Assembly IFA-432 as a part of the program entitled ''Experimental Vertification of Steady State Fuel Codes,'' sponsored by the Fuel Behavior Research Branch of the USNRC. The purpose of this program is to reduce the uncertainties of calculating the thermal stored energy in an operating nuclear fuel rod. The report presents fuel centerline thermocouple readings, cladding elongation monitor readings, rod internal pressure readings, and neutron detector readings. The neutron detector readings were corrected to represent rod local powers at the thermocouple locations. These data are presented in the form of plots of the variables versus time during the portion of the irradiation period from December 1975 to January 1978. Also included are descriptions of the test rationale, assembly and rod designs, test facility, instrument array and calibration, and data processing methods. Topical reports discussing specific aspects and results of the data analysis are referenced. As of May 1978, the assembly burnup had reached its design goal of 20,000 MWd/MTM. However, it has been decided to leave the assembly in core to collect high burnup fission gas release data. The xenon-filled Rod 4 was replaced with the non-instrumented Rod 8 (Rod 1 design) after the first cycle. Six of the twelve original thermocouples, four of the six cladding elongation monitors, all SPND'S and all pressure transducers remain operable at this writing

  4. AECL's advanced code program

    Energy Technology Data Exchange (ETDEWEB)

    McGee, G.; Ball, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2012-07-01

    This paper discusses the advanced code project at AECL.Current suite of Analytical, Scientific and Design (ASD) computer codes in use by Canadian Nuclear Power Industry is mostly developed 20 or more years ago. It is increasingly difficult to develop and maintain. It consist of many independent tools and integrated analysis is difficult, time consuming and error-prone. The objectives of this project is to demonstrate that nuclear facility systems, structures and components meet their design objectives in terms of function, cost, and safety; demonstrate that the nuclear facility meets licensing requirements in terms of consequences of off-normal events; dose to public, workers, impact on environment and demonstrate that the nuclear facility meets operational requirements with respect to on-power fuelling and outage management.

  5. Final irradiation and postirradiation data from the NRC/PNL instrumented assembly IFA-432

    International Nuclear Information System (INIS)

    Lanning, D.D.; Bradley, E.R.

    1986-02-01

    The instrumented six-rod test assembly IFA-432, sponsored by USNRC, operated in the Halden Reactor from December 1975 to May 1984, with surviving fuel thermocouples, neutron detectors and pressure transducers. Peak burnups of 46 MWd/kgM were achieved. Interim destructive examination data were obtained at peak burnups of 24 and 34 MWd/kgM. This paper presents a synopsis of the irradiation histories and postirradiation examination data for the high burnup rods. The postirradiation condition of the rods correlates well with their individual design parameters and operating conditions

  6. IFPE/IFA-432, Fission Gas Release, Mechanical Interaction BWR Fuel Rods, Halden

    International Nuclear Information System (INIS)

    Turnbull, J.A.

    1996-01-01

    Description: It contains data from experiments that have been performed at the IFE/OECD Halden Reactor Project, available for use in fuel performance studies. It covers experiments on thermal performance, fission product release, clad properties and pellet clad mechanical interaction. It includes also experimental data relevant to high burn-up behaviour. IFA-432: Measurements of fuel temperature response, fission gas release and mechanical interaction on BWR-type fuel rods up to high burn-ups. The assembly featured several variations in rod design parameters, including fuel type, fuel/cladding gap size, fill gas composition (He and Xe) and fuel stability. It contained 6 BWR-type fuel rods with fuel centre thermocouples at two horizontal planes, rods were also equipped with pressure transducers and cladding extensometers. Only data from 6 rods are compiled here

  7. New capabilities of the lattice code WIMS-AECL

    International Nuclear Information System (INIS)

    Altiparmakov, Dimitar

    2008-01-01

    The lattice code WIMS-AECL has been restructured and rewritten in Fortran 95 in order to increase the accuracy of its responses and extend its capabilities. Significant changes of computing algorithms have been made in the following two areas: geometric calculations and resonance self-shielding. Among various geometry enhancements, the code is no longer restricted to deal with single lattice cell problems. The multi-cell capability allows modelling of various lattice structures such as checkerboard lattices, a de-fuelled channel, and core-reflector interface problems. The new resonance method performs distributed resonance self-shielding including the skin effect. This paper describes the main code changes and presents selected code verification results. (authors)

  8. Analysis of fuel relocation for the NRC/PNL Halden assemblies IFA-431, IFA-432, and IFA-513. Interim report

    International Nuclear Information System (INIS)

    Williford, R.E.; Mohr, C.L.; Lanning, D.D.; Cunningham, M.E.; Rausch, W.N.

    1980-06-01

    The effects of the thermally-induced cracking and subsequent relocation of UO2 fuel pellets on the thermal and mechanical behavior of light-water reactor fuel rods during irradiation are quantified in this report. Data from the Nuclear Regulatory Commission/Pacific Northwest Laboratory Halden experiments on instrumented fuel assemblies (IFA) IFA-431, IFA-432, and IFA-513 are analyzed. Beginning-of-life in-reactor measurements of fuel center temperatures, linear heat ratings, and cladding axial elongations are used in a new model to solve for the effective thermal conductivity and elastic moduli of the cracked fuel column. The primary assumptions of the new model are that (1) the cracked fuel is in a hydrostatic state of stress in the (r,theta) plane, and that (2) there is no axial slipping between fuel and cladding. Three basic parameters are used to describe the cracked fuel: (1) the crack pattern, (2) the crack roughness, and (3) the fuel surface (gap) roughness. Recommendations are made on refining the model

  9. Interface code between WIMS-AECL and RFSP-IST for coupling computing

    International Nuclear Information System (INIS)

    Xu Liangwang; Liu Yu; Jia Baoshan

    2007-01-01

    A code based on the protocols of Telnet and FTP is developed with C++ for coupling computing between WIMS-AECL and RFSP-IST. the input document of WIMS-AECL and RFSP-ISP cna be generated automatically and be submitted to server, the output document will be downloaded by the end of computing. the function of analyzing standard output document is also included in this code. After simple updating, this code can meet the requirement of other code using input document, e.g. CATHENA. A pilot study of the relation between void fraction and reactivity in TACR, some valuable conclusions has been achieved. (authors)

  10. The development, qualification and availability of AECL analytical, scientific and design codes

    International Nuclear Information System (INIS)

    Kupferschmidt, W.C.H.; Fehrenbach, P.J.; Wolgemuth, G.A.; McDonald, B.H.; Snell, V.G.

    2001-01-01

    Over the past several years, AECL has embarked on a comprehensive program to develop, qualify and support its key safety and licensing codes, and to make executable versions of these codes available to the international nuclear community. To this end, we have instituted a company-wide Software Quality Assurance (SQA) Program for Analytical, Scientific and Design Computer Programs to ensure that the design, development, maintenance, modification, procurement and use of computer codes within AECL is consistent with today's quality assurance standards. In addition, we have established a comprehensive Code Validation Project (CVP) with the goal of qualifying AECL's 'front-line' safety and licensing codes by 2001 December. The outcome of this initiative will be qualified codes, which are properly verified and validated for the expected range of applications, with associated statements of accuracy and uncertainty for each application. The code qualification program, based on the CSA N286.7 standard, is intended to ensure (1) that errors are not introduced into safety analyses because of deficiencies in the software, (2) that an auditable documentation base is assembled that demonstrates to the regulator that the codes are of acceptable quality, and (3) that these codes are formally qualified for their intended applications. Because AECL and the Canadian nuclear utilities (i.e., Ontario Power Generation, Bruce Power, Hydro Quebec and New Brunswick Power) generally use the same safety and licensing codes, the nuclear industry in Canada has agreed to work cooperatively together towards the development, qualification and maintenance of a common set of analysis tools, referred to as the Industry Standard Toolset (IST). This paper provides an overview of the AECL Software Quality Assurance Program and the Code Validation Project, and their associated linkages to the Canadian nuclear community's Industry Standard Toolset initiative to cooperatively qualify and support commonly

  11. Sensitivity analysis on various parameters for lattice analysis of DUPIC fuel with WIMS-AECL code

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Gyu Hong; Choi, Hang Bok; Park, Jee Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    The code WIMS-AECL has been used for the lattice analysis of DUPIC fuel. The lattice parameters calculated by the code is sensitive to the choice of number of parameters, such as the number of tracking lines, number of condensed groups, mesh spacing in the moderator region, other parameters vital to the calculation of probabilities and burnup analysis. We have studied this sensitivity with respect to these parameters and recommend their proper values which are necessary for carrying out the lattice analysis of DUPIC fuel.

  12. Sensitivity analysis on various parameters for lattice analysis of DUPIC fuel with WIMS-AECL code

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Gyu Hong; Choi, Hang Bok; Park, Jee Won [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    The code WIMS-AECL has been used for the lattice analysis of DUPIC fuel. The lattice parameters calculated by the code is sensitive to the choice of number of parameters, such as the number of tracking lines, number of condensed groups, mesh spacing in the moderator region, other parameters vital to the calculation of probabilities and burnup analysis. We have studied this sensitivity with respect to these parameters and recommend their proper values which are necessary for carrying out the lattice analysis of DUPIC fuel.

  13. Validation of DRAGON code in connection with WIMS-AECL/RFSP code system based on ENDF/B-VI library and two group model

    International Nuclear Information System (INIS)

    Hong, In Seob; Suk, Ho Chun; Kim, Soon Young; Jo, Chang Keun

    2002-06-01

    The major objective of this research is to validate the incremental cross section property of DRAGON code in connection with WIMS-AECL/DRAGON/RFSP code system with ENDF/B-VI library and full 2G calculation model. The direct comparison between the incremental cross section results calculated by DRAGON with ENDF/B-VI and ENDF/B-V and MULTICELL with ENDF/B-V indicate that there are not much differences between the incremental cross sections of DRAGON with ENDF/B-V and ENDF/B-VI, but there exists large discrepancies between the results of DRAGON and those of MULTICELL. In the analysis of the difference between calculated and measured reactivity worths of various types of control devices during Phase-B Post-Simulation of Wolsong Units 2, 3 and 4, WIMS-AECL/DRAGON/RFSP analysis well agrees with those of previous WIMS-AECL /MULTICELL/RFSP analysis within very small differences. From those results, we can conclude that DRAGON code can be used as a general purpose incremental cross section generation tool for not only the natural uranium fuel but also slightly enriched fuel such as RU or SEU, to cover the shortcomings of natural uranium based MULTICELL code

  14. AECL international standard problem ISP-41 FU/1 follow-up exercise (Phase 1): Containment Iodine Computer Code Exercise: Parametric Studies

    International Nuclear Information System (INIS)

    Ball, J.; Glowa, G.; Wren, J.; Ewig, F.; Dickenson, S.; Billarand, Y.; Cantrel, L.; Rydl, A.; Royen, J.

    2001-06-01

    This report describes the results of the second phase of International Standard Problem (ISP) 41, an iodine behaviour code comparison exercise. The first phase of the study, which was based on a simple Radioiodine Test Facility (RTF) experiment, demonstrated that all of the iodine behaviour codes had the capability to reproduce iodine behaviour for a narrow range of conditions (single temperature, no organic impurities, controlled pH steps). The current phase, a parametric study, was designed to evaluate the sensitivity of iodine behaviour codes to boundary conditions such as pH, dose rate, temperature and initial I- concentration. The codes used in this exercise were IODE (IPSN), IODE (NRIR), IMPAIR (GRS), INSPECT (AEAT), IMOD (AECL) and LIRIC (AECL). The parametric study described in this report identified several areas of discrepancy between the various codes. In general, the codes agree regarding qualitative trends, but their predictions regarding the actual amount of volatile iodine varied considerably. The largest source of the discrepancies between code predictions appears to be their different approaches to modelling the formation and destruction of organic iodides. A recommendation arising from this exercise is that an additional code comparison exercise be performed on organic iodide formation, against data obtained from intermediate-scale studies (two RTF (AECL, Canada) and two CAIMAN facility (IPSN, France) experiments have been chosen). This comparison will allow each of the code users to realistically evaluate and improve the organic iodide behaviour sub-models within their codes. (authors)

  15. AECL present and future

    International Nuclear Information System (INIS)

    Foster, J.S.

    The history and present activities of the Crown corporation AECL are described. AECL owns limited interests in nuclear power plants and a Manitoba transmission system. AECL is the world's foremost producer of heavy water, and exports CANDU type reactors and radiation processing equipment. AECL backs up the Canadian nuclear power program wherever there is no conflict with private enterprise. (E.C.B.)

  16. WIMS-AECL/RFSP code validation of reactivity calculations following a long shutdown using the simple-cell history-based method

    International Nuclear Information System (INIS)

    Ardeshiri, F.; Donnelly, J.V.; Arsenault, B.

    1998-01-01

    The purpose of this analysis is to validate the Reactor Fuelling Simulation Program (RFSP) using the simple-cell model (SCM) history-based method in a startup simulation following a reactor shutdown period. This study is part of the validation work for history-based calculations, using the WIMS-AECL code with the ENDF/B-V library, and the SCM linked to the RFSP code. In this work, the RFSP code with the SCM history-based method was used to track a 1-year period of the Point Lepreau reactor operating history, that included a 12-day reactor shutdown and subsequent startup. Measured boron and gadolinium concentrations were used in the RFSP simulations, and the predicted values of core reactivity were compared to the reference (pre-shutdown) value. The discrepancies in core reactivity are shown to be better than ±2 milli-k at any time, and better than about ±0.5 milli-k towards the end of the startup transient. The results of this analysis also show that the calculated maximum channel and bundle powers are within an acceptable range during both the core-follow and the reactor startup simulations. (author)

  17. Description of the resonance treatment in WIMS-AECL

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, J V

    1993-05-01

    The Stamm`ler resonance treatment as applied within the WIMS-AECL lattice cell code is described. The validation work demonstrating the accuracy of the resonance treatment is reviewed and indicates that the methods used will be accurate for the current range of application within AECL. (author). 22 refs., 6 tabs.

  18. AECL's new environmental initiatives

    International Nuclear Information System (INIS)

    McDonnell, F.N.

    1993-01-01

    AECL's research and development expenditures in environmental sciences and waste management technology are about $50 M per year. The main focus of these programs is the Nuclear Fuel Waste Management Program. This research is supplemented by activities in support of laboratory, Environmental Authority and internal waste management requirements, as well as provision of non-nuclear services. AECL intends to become more involved in performing environmental research and development with broader application. The goal is to achieve a relationship with Canadian industry that would involve a substantial portion of AECL's environmental research capabilities. The research directions and priorities of the resulting partnership would be set by the private sector in accordance with their needs and requirements. It is expected that the activities associated with this new environmental initiative will start small and grow in response to perceived needs. AECL is now increasing its non-nuclear research efforts by targeting those markets that appear most attractive. The thrust can be divided into three broad categories: environmental research, environmental services, and environmental products. (Author)

  19. Final report of the AECL/SKB Cigar Lake analog study. AECL research No. AECL-10851

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, J J; Smellie, J A.T. [eds.

    1994-07-15

    AECL has conducted natural analog studies on the Cigar Lake uranium deposit in northern Saskatchewan since 1984 as part of the Canadian Nuclear Fuel Waste Management Program. This report provides background information and summarizes the results of the study, emphasizing the analog aspects and the implications of modelling activities related to the performance assessment of disposal concepts for nuclear fuel wastes developed in both Canada and Sweden. The study was undertaken to obtain an understanding of the process involved in, and the effects of, steady-state water-rock interaction and trace-element migration in and around the deposit, including paleo-migration processes since the deposit was formed. To achieve these objectives, databases and models were produced to evaluate the equilibrium thermodynamic codes and databases; the role of colloids, organics, and microbes in transport processes for radionuclides; and the stability of UO2 and the influence of radiolysis on UO2 dissolution and radionuclide migration.

  20. The AECL operator companion

    International Nuclear Information System (INIS)

    Lupton, L.R.; Anderson, L.L.; Basso, R.A.J.

    1989-11-01

    As CANDU plants become more complex, and are operated under tighter constraints and for longer periods between outages, plant operations staff will have to absorb more information to correctly and rapidly respond to upsets. A development program is underway at AECL to use expert systems and interactive media tools to assist operations staff of existing and future CANDU plants. The complete system for plant information access and display, on-line advice and diagnosis, and interactive operating procedures is called the Operator Companion. A prototype, consisting of operator consoles, expert systems and simulation modules in a distributed architecture, is currently being developed to demonstrate the concepts of the Operator Companion

  1. AECL's plant Information Technologies

    International Nuclear Information System (INIS)

    DeVerno, M.; Lupton, L.; Didsbury, R.; Judd, R.

    1998-01-01

    The competitiveness of the world-wide energy market is a continual driving force for improvements to CANDU performance and lower operating, maintenance, and administration costs. As in other industries, advanced Information Technologies (IT) are changing the way we work and conduct business. The nuclear industry is no different and there exists strong incentives to improve work processes and provide faster and more flexible access to the information needed to effectively manage and maintain nuclear plant assets. AECL has responded to these forces through the development of a vision of integrated IT systems addressing all phases of nuclear plant development and operations. This includes the initial engineering, design, and construction processes as well as support to the long-term operations and maintenance. Integral to the AECL vision is the need for cost-effective engineering and operational configuration management systems, proactive maintenance processes and systems, and advanced plant surveillance and diagnostics. This paper presents the vision and describes the integrated information systems needed to manage both the design basis and operating plant data systems to ensure the cost-effective, long-term viability of CANDU plants. (author)

  2. Thermalhydraulic analyses of AECL`s spent fuel dry storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Moffett, R; Sabourin, G [Atomic Energy of Canada Ltd., Montreal, PQ (Canada). CANDU Operations; Banas, A O [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

    1996-12-31

    This paper presents the validation of one- and three-dimensional thermalhydraulic models to be used to evaluate the thermal performance of AECL`s MACSTOR and CANSTOR spent fuel dry storage modules. For this purpose, we compared analytical results to results of experiments conducted at AECL`s Whiteshell Laboratories where mockups of the MACSTOR module and of a CANDU fuel storage basket were tested. The paper shows improvements to a simple one-dimensional model of the MACSTOR mock-up used previously. The replacement of constant heat transfer coefficients by free convection correlations, the addition of a storage cylinder model, and the addition of a radiation heat transfer model improved the predictions of concrete and storage cylinder temperatures. The paper also presents a new three-dimensional model for flow and heat transfer in the MACSTOR mock-up developed using CFDS-FLOW3D and -RAD3D computer programs. CFDS-FLOW3D code can estimate loss coefficients in complex geometry to an accuracy better than standard engineering correlations. The flow and temperature fields predicted using CFDS-FLOW3D are consistent with the measurements made during MACSTOR mock-up experiments (author). 5 refs., 4 tabs., 9 figs.

  3. AECL research programs in chemistry

    International Nuclear Information System (INIS)

    Crocker, I.H.; Eastwood, T.A.; Smith, D.R.; Stewart, R.B.; Tomlinson, M.; Torgerson, D.F.

    1980-09-01

    Fundamental or underlying research in chemistry is being done in AECL laboratories to further the understanding of processes involved in current nuclear energy systems and maintain an awareness of progress at the frontiers of chemical research so that new advances can be turned to advantage in future AECL endeavours. The report introduces the current research topics and describes them briefly under the following headings: radiation chemistry, isotope separation, high temperature solution chemistry, fuel reprocessing chemistry, and analytical chemistry. (auth)

  4. AECL annual review 1992 - 1993

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    1992/93 was a pivotal year for AECL, with the redirection of its strategic plan, the refocussing of its corporate mission, a change in its structural organization to meet new challenges, the contract with South Korea for Wolsong Units 3 and 4 and the Memorandum of Understanding with Saskatchewan. AECL looks forward to the next 12 months as a time of opportunity, confident in the knowledge that they possess the means to succeed. ills.

  5. AECL annual review 1992 - 1993

    International Nuclear Information System (INIS)

    1993-01-01

    1992/93 was a pivotal year for AECL, with the redirection of its strategic plan, the refocussing of its corporate mission, a change in its structural organization to meet new challenges, the contract with South Korea for Wolsong Units 3 and 4 and the Memorandum of Understanding with Saskatchewan. AECL looks forward to the next 12 months as a time of opportunity, confident in the knowledge that they possess the means to succeed. ills

  6. AECL's reliability and maintainability program

    International Nuclear Information System (INIS)

    Wolfe, W.A.; Nieuwhof, G.W.E.

    1976-05-01

    AECL's reliability and maintainability program for nuclear generating stations is described. How the various resources of the company are organized to design and construct stations that operate reliably and safely is shown. Reliability and maintainability includes not only special mathematically oriented techniques, but also the technical skills and organizational abilities of the company. (author)

  7. Analysis of flow-induced vibration of heat exchanger and steam generator tube bundles using the AECL computer code PIPEAU-2

    International Nuclear Information System (INIS)

    Gorman, D.J.

    1983-12-01

    PIPEAU-2 is a computer code developed at the Chalk River Nuclear Laboratories for the flow-induced vibration analysis of heat exchanger and steam generator tube bundles. It can perform this analysis for straight and 'U' tubes. All the theoretical work underlying the code is analytical rather than numerical in nature. Highly accurate evaluation of the free vibration frequencies and mode shapes is therefore obtained. Using the latest experimentally determined parameters available, the free vibration analysis is followed by a forced vibration analysis. Tube response due to fluid turbulence and vortex shedding is determined, as well as critical fluid velocity associated with fluid-elastic instability

  8. Hydrogen recombiner development at AECL

    International Nuclear Information System (INIS)

    Dewit, W.A.; Koroll, G.W.; Loesel Sitar, J.; Graham, W.R.C.

    1997-01-01

    Catalytic recombiners have been developed at AECL for the purpose of hydrogen removal in post-accident nuclear containment buildings. The recombiners are based on a particular catalyst designed by AECL which has extraordinary resistance to fouling from water and water vapour and a large thermodynamic range of operation. The catalysts were developed, originally, for the purpose of heavy water manufacturing by way of a catalytic exchange process. Application of these catalyst materials in recombiners for containment applications began in the late 1980's. The first application was a passive recombiner, qualified for use in control of radiolytic hydrogen in the headspace of a pool-type experimental reactor of AECL design in 1988. The passive, or natural convection recombiner concept has continued development to commercial stage for application in power reactor containments. This paper reviews the AECL recombiner development, describes the current model and shows results from tests of full-scale recombiners in the Large Scale Vented Combustion Test Facility at AECL-WL. The AECL recombiner is designed for compactness and ease of engineering into containment. The design is a simple, open-ended rectangular enclosure with catalyst elements arranged inside to promote optimum convective flow driven by heat of recombination at the catalyst surface. Self start, as evidenced by catalyst heating and initiation of flow, is achieved in less than 1% hydrogen, with available oxygen, at room temperature and 100% relative humidity. This low temperature start-up in condensing atmospheres is viewed as the most challenging condition for wet-proofing effectiveness. Cold start-up is a vital performance requirement in containments, such as CANDU, where engineered air-cooling systems are operating and where long-term hydrogen control is required, after containment atmospheres have cooled. Once started, the removal capacity scales linearly with the inlet cross-section area and the partial

  9. Radioactive waste management at AECL

    International Nuclear Information System (INIS)

    Gadsby, R.D.; Allan, C.J.

    2003-01-01

    AECL has maintained an active program in radioactive waste management since 1945, when the Canadian nuclear program commenced activities at the Chalk River Laboratories (CRL). Waste management activities have included operation of waste management storage and processing facilities at AECL's CRL and Whiteshell Laboratories (WL); operation of the Low Level Radioactive Waste Management Office on behalf of Natural Resources Canada to resolve historic radioactive waste problems (largely associated with radioactive ore recovery, transport and processing operations) that are the responsibility of the Federal Government; development of the concept and related technology for geological disposal of Canada's nuclear fuel waste; development of the Intrusion-Resistant Underground Structure (IRUS) disposal concept for low-level nuclear waste; development of dry storage technology for the interim storage of used fuel; and development and assessment of waste processing technology for application in CANDU nuclear power plants and at CRL and WL. Today these activities are continuing. In addition, AECL is: preparing to decommission the nuclear facilities at WL; carrying out a number of smaller decommissioning projects at CRL; putting in place projects to upgrade the low-level liquid waste processing capabilities of the CRL Waste Treatment Centre, recover and process highly active liquid wastes currently in storage, and recover, condition and improve the storage of selected fuel wastes currently stored in below-ground standpipes in the CRL waste management areas; and assessing options for additional remediation projects to improve the management of other wastes currently in storage and to address environmental contamination from past practices. (author)

  10. Annual report 1997--1998. AECL research number AECL-11964

    International Nuclear Information System (INIS)

    1998-01-01

    This is the Annual report of AECL, the legal name of Atomic Energy of Canada Limited. Its mandate is to undertake research into nuclear energy and to develop commercial applications for its developments. This annual report presents information on marketing and commercial operations, product development, CANDU research, waste management and nuclear sciences, environmental management and site refurbishment. A financial review is included, along with management responsibility, an Auditor's report, financial statements, a five-year financial summary, and a list of directors and locations

  11. Development of advanced ceramics at AECL

    International Nuclear Information System (INIS)

    Palmer, B.J.F.; MacEwen, S.R.; Sawicka, B.D.; Hayward, P.J.; Sridhar, S.

    1986-12-01

    Atomic Energy of Canada Limited (AECL) has a long history of developing ceramics for nuclear fission and fusion applications. AECL is now applying its multidisciplinary materials R and D capabilities, including unique capabilities in ceramic processing and nondestructive evaluation, to develop advanced ceramic materials for commercial and industrial applications. This report provides an overview of the facilities and programs associated with the development of advanced ceramics at AECL

  12. Development of square and hexagonal lattice analysis capability in WIMS-AECL

    International Nuclear Information System (INIS)

    Donnelly, J.V.

    1990-11-01

    WIMS, originally developed by the UKAEA (Winfrith), is a widely used computer code for reactor physics analysis of lattice cells. WIMS-AECL (Atomic Energy of Canada Limited) has been developed from a version of the code received from Winfrith in the early 1970s and is generally used within AECL. The facilities existing in the original version of WIMS were very capable for the analysis of reactor designs normally encountered within AECL at that time, such as CANDU fuel lattices, but had limitations in the analysis of more general reactor geometries, such as square light-reactor assemblies. This paper discusses the development and testing of modifications to the two-dimensional collision-probability calculation module in WIMS-AECL to enable more rigorous analysis of lattice geometries based on square or hexagonal cells

  13. AECL's mixed waste management program

    International Nuclear Information System (INIS)

    Peori, R.; Hulley, V.

    2006-01-01

    Every nuclear facility has it, they wish that they didn't but they have generated and do possess m ixed waste , and until now there has been no permanent disposition option; it has been for the most been simply maintained in interim storage. The nuclear industry has been responsibly developing permanent solutions for solid radioactive waste for over fifty years and for non-radioactive, chemically hazardous waste, for the last twenty years. Mixed waste (radioactive and chemically hazardous waste) however, because of its special, duo-hazard nature, has been a continuing challenge. The Hazardous Waste and Segregation Program (HW and SP) at AECL's CRL has, over the past ten years, been developing solutions to deal with their own in-house mixed waste and, as a result, have developed solutions that they would like to share with other generators within the nuclear industry. The main aim of this paper is to document and describe the early development of the solutions for both aqueous and organic liquid wastes and to advertise to other generators of this waste type how these solutions can be implemented to solve their mixed waste problems. Atomic Energy of Canada Limited (AECL) and in particular, CRL has been satisfactorily disposing of mixed waste for the last seven years. CRL has developed a program that not only disposes of mixed waste, but offers a full service mixed waste management program to customers within Canada (that could eventually include U.S. sites as well) that has developed the experience and expertise to evaluate and optimize current practices, dispose of legacy inventories, and set up an efficient segregation system to reduce and effectively manage, both the volumes and expense of, the ongoing generation of mixed waste for all generators of mixed waste. (author)

  14. The AECL reactor development programme

    International Nuclear Information System (INIS)

    Menelely, D.A.

    1997-01-01

    The modem CANDU-PHWR power reactor is the result of more than 50 years of evolutionary design development in Canada. It is one of only three commercially successful designs in the world to this date. The basis for future development is the CANDU 6 and CANDU 9 models. Four of the first type are operating and four more will go an line before the end of this decade. The CANDU 9 is a modernized single-unit version of the twelve large multi-unit plants operated by Ontario Hydro. All of these plants use proven technology which resulted from research, development, design construction, and operating experience over the past 25 years. Looking forward another 25 years, AECL plans to retain all of the essential features that distinguish today's CANDU reactors (heavy water moderation, on-power fuelling simple bundle design, horizontal fuel channels, etc.). The end product of the planned 25-year development program is more than a specific design - it is a concept which embodies advanced features expected from ongoing R and D programs. To carry out the evolutionary work we have selected seven main areas for development: Safety Technology, Fuel and Fuel Cycles, Fuel Channels, Systems and Components, Heavy Water and Tritium Information Technology, and Construction. There are three strategic measures of success for each of these work areas: improved economics, advanced fuel cycle utilization, and enhanced safety/plant robustness. The paper describes these work programs and the overall goals of each of them. (author)

  15. The Y2K program for scientific-analysis computer programs at AECL

    International Nuclear Information System (INIS)

    Popovic, J.; Gaver, C.; Chapman, D.

    1999-01-01

    The evaluation of scientific-analysis computer programs for year-2000 compliance is part of AECL' s year-2000 (Y2K) initiative, which addresses both the infrastructure systems at AECL and AECL's products and services. This paper describes the Y2K-compliance program for scientific-analysis computer codes. This program involves the integrated evaluation of the computer hardware, middleware, and third-party software in addition to the scientific codes developed in-house. The project involves several steps: the assessment of the scientific computer programs for Y2K compliance, performing any required corrective actions, porting the programs to Y2K-compliant platforms, and verification of the programs after porting. Some programs or program versions, deemed no longer required in the year 2000 and beyond, will be retired and archived. (author)

  16. The Y2K program for scientific-analysis computer programs at AECL

    International Nuclear Information System (INIS)

    Popovic, J.; Gaver, C.; Chapman, D.

    1999-01-01

    The evaluation of scientific analysis computer programs for year-2000 compliance is part of AECL's year-2000 (Y2K) initiative, which addresses both the infrastructure systems at AECL and AECL's products and services. This paper describes the Y2K-compliance program for scientific-analysis computer codes. This program involves the integrated evaluation of the computer hardware, middleware, and third-party software in addition to the scientific codes developed in-house. The project involves several steps: the assessment of the scientific computer programs for Y2K compliance, performing any required corrective actions, porting the programs to Y2K-compliant platforms, and verification of the programs after porting. Some programs or program versions, deemed no longer required in the year 2000 and beyond, will be retired and archived. (author)

  17. AECL annual review 1991-1992

    International Nuclear Information System (INIS)

    1992-01-01

    Formed as a Crown Corporation in 1952, AECL consists of two main divisions: AECL CANDU, based in Missisauga and Montreal, responsible for the development, design, marketing and project management of CANDU nuclear power projects; and AECL Research, with its head office in Ottawa and laboratories in Chalk River, Ontario and Pinawa, Manitoba, which supports CANDU and performs the research, development, demonstration and marketing required to apply nuclear sciences and their associated technologies. A strategic plan is under development, which will address the issues of market identification, key partnerships, securing the CANDU technology base, export financing and optimum business structure. In 1991/92 operating income was $16.4 million, up from $7.8 million in 1990/91. Good progress was made on goals to revitalize and upgrade AECL employee's skills and productivity. Key goals for AECL CANDU were: launching the Wolsung 2 reactor project in south Korea; closing the timing and product options for Wolsong 3 and 4; securing new business for Cernavoda 1; and attaining an agreement with either Saskatchewan Power Corp. or the New Brunswick Electric Power Commission regarding the timing of their CANDU 3 projects. Some success was achieved in the first three goals; Saskatchewan has chosen not to proceed with its CANDU 3 plant, but negotiations are continuing in New Brunswick. Key goals for AECL Research were: securing an advanced CANDU research and development program outside the CANDU Owners Group; Disposing of remaining non-nuclear technologies by spin-off, licensing or close-out; rationalizing commercial operations to generate increased revenues; and obtaining the Atomic Energy Control Board's approval of the NRU reactor assessment basis document. Progress was made on all goals

  18. Feasibility study on application of WIMS-AECL to Wolsong-1 refueling simulation

    International Nuclear Information System (INIS)

    Kim, Y.; Lee, S.

    2005-01-01

    'Full text:' At present, in Wolsong nuclear power plant, all of the reactor physics calculations are based on the cell code POWDERPUFS-V (PPV). PPV code use semi-empirical approximation rather than direct solving of transport equation with robust methodology. Switch from PPV to more robust transport solver is world-wide trend in addition to GAI issued from Canadian regulatory body (CNSC). In this paper, feasibility study on the replacement of cell code POWDERPUFS-V (PPV) with WIMS-AECL was performed for Wolsong-1 NPP. The impact of the cell code replacement on physics design parameters and refueling simulation was assessed. First, fuel isotopic composition affecting core reactivity is compared between PPV and WIMS-AECL. Generally it was shown that WIMS-AECL predicts higher uranium fissile concentration while less plutonium concentration as fuel burnup increases compared with prediction of PPV. Infinite multiplication factor of WIMS-AECL is slightly less predicted than that of PPV. Also core reactivity change from operating condition change such as moderator temperature, coolant temperature, fuel temperature and coolant density were compared for both fresh fuel and equilibrium fuel. Specially the analysis of void reactivity which is current hot issue for positive reactivity insertion in LOCA was also performed. As a result of this study, all of WIMS-AECL results were similar to PPV based calculation in the fresh fuel. However, there is a tendency that the deviation between the two codes increases as the fuel burn-up increases. This is because PPV code was made from the laboratory condition with fresh fuel and low fuel temperature. Second, refueling simulation with WIMS-AECL based RFSP was tried to compare with current PPV based RFSP simulation for about 20 months (5775FPD ∼ 6324FPD). To cover wide range of operating parameter condition such as purity of moderator and coolant and boron concentration, tremendous amount of computation time is needed with WIMS-AECL

  19. Validation of WIMS-AECL/(MULTICELL)/RFSP system by the results of phase-B test at Wolsung-II unit

    Energy Technology Data Exchange (ETDEWEB)

    Hong, In Seob; Min, Byung Joo; Suk, Ho Chun [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-03-01

    The object of this study is the validation of WIMS-AECL lattice code which has been proposed for the substitution of POWDERPUFS-V(PPV) code. For the validation of this code, WIMS-AECL/(MULTICELL)/RFSP (lattice calculation/(incremental cross section calculation)/core calculation) code system has been used for the Post-Simulation of Phase-B physics Test at Wolsung-II unit. This code system had been used for the Wolsong-I and Point Lepraeu reactors, but after a few modifications of WIMS-AECL input values for Wolsong-II, the results of WIMS-AECL/RFSP code calculations are much improved to those of the old ones. Most of the results show good estimation except moderator temperature coefficient test. And the verification of this result must be done, which is one of the further work. 6 figs., 15 tabs. (Author)

  20. Advancing CANDU technology AECL's Development program

    International Nuclear Information System (INIS)

    Torgerson, D.F.

    1997-01-01

    AECL has a comprehensive product development program that is advancing all aspects of CANDU technology including fuel and fuel cycles, fuel channels, heavy water and tritium technology, safety technology, components and systems, constructability, health and environment, and control and instrumentation. The technology arising from these programs is being incorporated into the CANDU design through an evolutionary process. This evolutionary process is focused on improving economics, enhancing safety and ensuring fuel cycle flexibility to secure fuel supply for the foreseeable future. This strategic thrusts are being used by CANDU designers and researchers to set priorities and goals for AECL's development activities. The goals are part of a 25-year development program that culminates in the 'CANDU X'. The 'CANDU X' is not a specific design - it is a concept that articulates our best extrapolation of what is achievable with the CANDU design over the next 25 years, and includes the advanced features arising from the R and D and engineering to be done over that time. AECL's current product, the 700 MWe class CANDU 6 and the 900 MWe class CANDU 9, both incorporate output from the development programs as the technology become available. A brief description of each development areas is given below. The paper ends with the conclusion that AECL has a clear vision of how CANDU technology and products will evolve over the next several years, and has structured a comprehensive development program to take full advantage of the inherent characteristics of heavy water reactors. (author)

  1. AECL annual report 1996-1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The 1996/1997 Annual Report of Atomic Energy of Canada Ltd. (AECL) is published and submitted to the Honourable member of parliament, Minister of Natural Resources. Included in this report are messages from marketing, commercial operations, product development, CANDU research, waste management, environmental management, financial review and copies of financial statements.

  2. AECL annual report 1996-1997

    International Nuclear Information System (INIS)

    1997-01-01

    The 1996/1997 Annual Report of Atomic Energy of Canada Ltd. (AECL) is published and submitted to the Honourable member of parliament, Minister of Natural Resources. Included in this report are messages from marketing, commercial operations, product development, CANDU research, waste management, environmental management, financial review and copies of financial statements

  3. Thermalhydraulic analyses of AECL's spent fuel dry storage systems

    International Nuclear Information System (INIS)

    Moffett, R.; Sabourin, G.

    1995-01-01

    This paper presents the validation of one- and three-dimensional thermalhydraulic models to be used to evaluate the thermal performance of AECL's MACSTOR and CANSTOR spent fuel dry storage modules. For this purpose, we compared analytical results to results of experiments conducted at AECL's Whiteshell Laboratories where mockups of the MACSTOR module and of a CANDU fuel storage basket were tested. The paper shows improvements to a simple one-dimensional model of the MACSTOR mock-up used previously. The replacement of constant heat transfer coefficients by free convection correlations, the addition of a storage cylinder model, and the addition of a radiation heat transfer model improved the predictions of concrete and storage cylinder temperatures. The paper also presents a new three-dimensional model for flow and heat transfer in the MACSTOR mock-up developed using CFDS-FLOW3D and -RAD3D computer programs. CFDS-FLOW3D code can estimate loss coefficients in complex geometry to an accuracy better than standard engineering correlations. The flow and temperature fields predicted using CFDS-FLOW3D are consistent with the measurements made during MACSTOR mock-up experiments (author). 5 refs., 4 tabs., 9 figs

  4. AECL's waste management and decommissioning program

    International Nuclear Information System (INIS)

    Kupferschmidt, W.C.H.

    2006-01-01

    Full text: Canada has developed significant expertise in radioactive waste management since the mid 1940s, when the Canadian nuclear program commenced activities at Chalk River Laboratories (CRL). Atomic Energy of Canada Limited (AECL), created as a Federal Crown Corporation in 1952, continues to manage wastes from these early days, as well as other radioactive wastes produced by Canadian hospitals, universities, industry, and operational wastes from AECL's current programs. AECL is also carrying out decommissioning of nuclear facilities and installations in Canada, predominantly at its own sites in Ontario (CRL, and the Douglas Point and Nuclear Power Demonstration prototype reactors), Manitoba (Whiteshell Laboratories) and Quebec (Gentilly-1 prototype reactor). At the CRL site, several major waste management enabling facilities are being developed to facilitate both the near- and long-term management of radioactive wastes. For example, the Liquid Waste Transfer and Storage Project is underway to recover and process highly radioactive liquid wastes, currently stored in underground tanks that, in some cases, date back to the initial operations of the site. This project will stabilize the wastes and place them in modern, monitored storage for subsequent solidification and disposal. Another initiative, the Fuel Packaging and Storage Project, has been initiated to recover and condition degraded used fuel that is currently stored in below-ground standpipes. The fuel will be then be stored in new facilities based on an adaptation of AECL's proven MACSTOR TM * dry storage system, originally designed for intermediate-term above-ground storage of used CANDU fuel bundles. Other commercial-based development work is underway to improve the storage density of the MACSTOR TM design, and to extend its application to interim storage of used LWR fuels as well as to the storage of intermediate-level radioactive waste arising from upcoming reactor refurbishment activities in Canada

  5. Compendium of the data used with the SYVAC3-CC3 system model. AECL research No. AECL-11013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    AECL is evaluating a concept for disposing of nuclear fuel waste from CANDU reactors deep in plutonic rock of the Canadian Shield. As part of this evaluation, models of the physical, chemical, geological, and biological processes that could occur in a sealed disposal vault designed to limit transport of contaminants to the accessible environment were developed. The mathematical models of the transport of radionuclides and toxic chemicals from nuclear fuel waste are incorporated into a computer model named the Systems Variability Analysis Code, Generation 3, and Canadian Concept Model, Generation 3 (SYVAC3-CC3). The report presents the data in the master database used by SYVAC3-CC3 for the postclosure assessment of deep geological disposal, derived from a major program of laboratory and field studies conducted by AECL Research over the past 15 years. The data represents characteristics of a hypothetical vault, certain geologic characteristics of the Whiteshell Research Area, and a general surface environment with a human population living a rural lifestyle on a portion of the Canadian Shield in central Canada.

  6. AECL's strategy for decommissioning Canadian nuclear facilities

    International Nuclear Information System (INIS)

    Joubert, W.M.; Pare, F.E.; Pratapagiri, G.

    1992-01-01

    The Canadian policy on decommissioning of nuclear facilities as defined in the Atomic Energy Control Act and Regulations is administered by the Atomic Energy Control Board (AECB), a Federal Government agency. It requires that these facilities be decommissioned according to approved plans which are to be developed by the owner of the nuclear facility during its early stages of design and to be refined during its operating life. In this regulatory environment, Atomic Energy of Canada (AECL) has developed a decommissioning strategy for power stations which consists of three distinctive phases. After presenting AECL's decommissioning philosophy, its foundations are explained and it is described how it has and soon will be applied to various facilities. A brief summary is provided of the experience gained up to date on the implementation of this strategy. (author) 3 figs.; 1 tab

  7. AECL's support to operating plants world wide

    International Nuclear Information System (INIS)

    Azeez, S.; Kakaria, B.K.; Hinchley, E.M.

    1998-01-01

    Through their operating records, CANDU reactors have established themselves as a successful and cost-effective source of electricity in Canada and abroad. They have proven to be safe, reliable and economical. A variety of factors have contributed to the enviable CANDU record, such as a sound design based on proven principles supported by effective development programs, along with dedicated plant owners committed to excellence in safely maintaining and operating their plants. Atomic Energy of Canada Limited (AECL), the CANDU designer, has continuously maintained a close relationship with owners/operators of the plants in Canada, Argentina, Romania and South Korea. AECL and the plant operators have all benefited from this strengthening relationship by sharing experience and information. CANDU plant operators have been required to respond decisively to the economic realities of downward cost pressures and deregulation. Operating, Maintenance and Administration (OM and A) costs are being given a new focus as plant owners review each cost element to improve the economic returns from their investments. Amongst the three main OM and A constituents, plant maintenance costs are the most variable and have the largest influence on effective plant operations. The correlation between effective plant maintenance and high capacity factors shows clearly the importance of proactive maintenance planning to reduce the frequency and duration of forced plant outages and their negative impacts on plant economics. This paper describes the management processes and organizational structures m AECL that support plant operations and maintenance in operating CANDU plants with cost effective products and services. (author)

  8. Validation of MCNP and WIMS-AECL/DRAGON/RFSP for ACR-1000 applications

    International Nuclear Information System (INIS)

    Bromley, Blair P.; Adams, Fred P.; Zeller, Michael B.; Watts, David G.; Shukhman, Boris V.; Pencer, Jeremy

    2008-01-01

    This paper gives a summary of the validation of the reactor physics codes WIMS-AECL, DRAGON, RFSP and MCNP5, which are being used in the design, operation, and safety analysis of the ACR-1000 R . The standards and guidelines being followed for code validation of the suite are established in CSA Standard N286.7-99 and ANS Standard ANS-19.3-2005. These codes are being validated for the calculation of key output parameters associated with various reactor physics phenomena of importance during normal operations and postulated accident conditions in an ACR-1000 reactor. Experimental data from a variety of sources are being used for validation. The bulk of the validation data is from critical experiments in the ZED-2 research reactor with ACR-type lattices. To supplement and complement ZED-2 data, qualified and applicable data are being taken from other power and research reactors, such as existing CANDU R units, FUGEN, NRU and SPERT research reactors, and the DCA critical facility. MCNP simulations of the ACR-1000 are also being used for validating WIMS-AECL/ DRAGON/RFSP, which involves extending the validation results for MCNP through the assistance of TSUNAMI analyses. Code validation against commissioning data in the first-build ACR-1000 will be confirmatory. The code validation is establishing the biases and uncertainties in the calculations of the WIMS-AECL/DRAGON/RFSP suite for the evaluation of various key parameters of importance in the reactor physics analysis of the ACR-1000. (authors)

  9. AECL's advanced CANDU reactor - the ACR

    International Nuclear Information System (INIS)

    Alizadeh, Ala; Allsop, Peter; Hedges, Ken; Hopwood, Jerry; Yu, Stephen

    2003-01-01

    The ACR, the next generation CANDU design, represents the next step in development of the CANDU family of designs. AECL has achieved significant incremental improvements to the mid-size CANDU 6 nuclear power plant through successive projects, both in design and in project delivery. Building on this knowledge base, AECL is continuing to adapt the CANDU design to develop the ACR. This paper summarizes the ACR design features, which include major improvements in economics, inherent safety characteristics, performance and construction methods. Aimed at producing electrical power at a capital cost significantly less than that of the current reactor designs, the ACR is an evolutionary design based on the very successful CANDU 6 reactor. The new ACR product is specifically designed to produce power at a cost competitive with other forms of power generation while achieving short construction times, improved safety, international licensability, high investor returns, and low investor risk. It achieves these targets by taking advantage of the latest advances in both pressure-tube and pressure-vessel reactor technologies and experience. The flexibility and development potential of the fuel channel approach also enables designs to be developed that address priorities identified in international long-term specification programs such as the US Department of Energy (DOE) sponsored Generation IV program and IAEA hosted INPRO program. ACR-700 can be built in 36 months with a 48 month project duration, and deliver a lifetime capacity factor in excess of 90%. Overall, the ACR design represents a balance of proven design basis and innovations to give step improvements in safety, reliability and economics. The ACR development program, now well into the detail design stage, includes parallel formal licensing in the USA and Canada. Based on the status of the ACR design and AECL's on-going experience delivering reactor projects on-time and on-budget, the first ACR could be in service by

  10. AECL experience in fuel channel inspection

    Energy Technology Data Exchange (ETDEWEB)

    Van Drunen, G. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Gunn, R. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada); Mayo, W.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Scott, D.A. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)

    1999-06-01

    Inspection of CANDU fuel channels (FC) is performed to ensure safe and economic reactor operation. CANDU reactor FCs have features that make them a unique non-destructive testing (NDT) challenge. The thin, 4 mm pressure-tube wall means flaws down to about 0.1 mm deep must be reliably detected and characterized. This is one to two orders of magnitude smaller than is usually considered of significant concern for steel piping and pressure vessels. A second unique feature is that inspection sensors must operate in the reactor core--often within 20 cm of highly radioactive fuel. Work on inspection of CANDU reactor FCs at AECL dates back over three decades. In that time, AECL staff have provided equipment and conducted or supervised in-service inspections in about 250 FCs, in addition to over 8000 pre-service FCs. These inspections took place at every existing CANDU reactor except those in India and Romania. Early FC inspections focussed on measurement of changes in dimensions (gauging) resulting from exposure to a combination of neutrons, stress and elevated temperature. Expansion of inspection activities to include volumetric inspection (for flaws) started in the mid-1970s with the discovery of delayed hydride cracking in Pickering 3 and 4 rolled joints. Recognition of other types of flaw mechanisms in the 1980s led to further expansion in both pre-service and in-service inspections. These growing requirements, to meet regulatory as well as economic needs, led to the development of a wide spectrum of inspection technology that now includes tests for hydrogen concentration, structural integrity of core components, flaws, and dimensional change. This paper reviews current CANDU reactor FC inspection requirements. The equipment and techniques developed to satisfy these requirements are also described. The paper concludes with a discussion of work in progress in AECL aimed at providing state-of-the-art FC inspection services. (author)

  11. AECL research programmes in materials science

    International Nuclear Information System (INIS)

    Cox, B.; Eastwood, T.A.; Mitchell, I.V.; Dutton, R.

    1980-10-01

    The high capacity factors achieved by CANDU nuclear power reactors can be attributed in part to the careful attention which has been paid in the concept and design phases to the selection of materials. Improved tolerance of these materials to the hostile conditions of a reactor core depends upon our understanding of such phenomena as radiation damage, corrosion and cracking. This report is an introduction to some of the fundamental and underlying research programmes that have evolved at the AECL laboratories in response to this need. The interactions of energetic atomic particles with solids on a microscopic scale are considered, first under the general heading of radiation effects, followed by sections on energy loss processes, ion channeling, and crystal lattice defects. The latter section leads into the important programmes on deformation processes (creep and growth) in zirconium. The final section discusses the extensive work on the oxidation and environmental cracking of zirconium alloys. (auth)

  12. AECL's progress in DUPIC fuel development

    International Nuclear Information System (INIS)

    Sullivan, J.D.; Ryz, M.A.; Lee, J.W.

    1997-01-01

    Previous papers described progress in choosing a fabrication route for the DUPIC (Direct Use of Spent PWR Fuel in CANDU) fuel cycle [1], details of the OREOX (Oxidation Reduction of Oxide fuel) process, and preliminary results of out-cell and small-scale in-cell experiments [2]. AECL's project to develop the DUPIC fuel cycle has now progressed to the stage of fabricating DUPIC fuel elements for irradiation testing in a research reactor. Because of the high radiation fields around the spent PWR fuel, all work is being done in hot cells. The equipment used for fabrication of the DUPIC fuel elements is described in this paper. The commissioning, in-cell installation and current status of the fabrication process are also described and plans for the completion of this phase of the DUPIC project are outlined. The goal of this phase of the project is demonstration of the technical feasibility of the DUPIC fuel cycle. (author)

  13. A bibliography of AECL publications on reactor safety

    International Nuclear Information System (INIS)

    Hawley, N.J.

    1979-12-01

    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)

  14. A bibliography of AECL publications on environmental research

    International Nuclear Information System (INIS)

    Hawley, N.J.

    1978-12-01

    Publications in the open literature on environmental research performed by AECL personnel are listed chronologically with the first entry dated 1951. It is intended that the bibliography should be brought up to date yearly. (author)

  15. Research reactor fuel development at AECL

    International Nuclear Information System (INIS)

    Sears, D.F.; Wang, N.

    2000-09-01

    This paper reviews recent U 3 Si 2 and U-Mo dispersion fuel development activities at AECL. The scope of work includes fabrication development, irradiation testing, post-irradiation examination and performance qualification. U-Mo alloys with a variety of compositions, ranging from 6 to 10 wt % Mo, have been fabricated with high purity and homogeneity in the product. The alloys and powders were characterized using optical and scanning electron microscopy, chemical analysis, and X-ray diffraction and neutron diffraction analysis. U-Mo powder samples have been supplied to the Argonne National Laboratory for irradiation testing in the ATR reactor. Low-enriched uranium fuel elements containing U-7 wt % Mo and U-10 wt % Mo with loadings up to 4.5 gU/cm 3 have been fabricated at CRL for irradiation testing in the NRU reactor. The U-Mo fuel elements will be tested in NRU at linear powers up to 145 kW/m, and to 85 atom % 235 U burnup. (author)

  16. Research reactor fuel development at AECL

    International Nuclear Information System (INIS)

    Sears, D.F.; Wang, N.

    2000-01-01

    This paper reviews recent U 3 Si 2 and U-Mo dispersion fuel development activities at AECL. The scope of work includes fabrication development, irradiation testing, postirradiation examination and performance qualification. U-Mo alloys with a variety of compositions, ranging from 6 to 10 wt % Mo, have been fabricated with high purity and homogeneity in the product. The alloys and powders were characterized using optical and scanning electron microscopy, chemical analysis, and X-ray diffraction and neutron diffraction analysis. U-Mo powder samples have been supplied to the Argonne National Laboratory for irradiation testing in the ATR reactor. Low-enriched uranium fuel elements containing U-7 wt % Mo and U-10 wt % Mo with loadings up to 4.5 gU/cm 3 have been fabricated at CRL for irradiation testing in the NRU reactor. The U-Mo fuel elements will be tested in NRU at linear powers up to 145 kW/m, and to 85 atom % 235 U burnup. (author)

  17. AECL IMPELA electron beam industrial irradiators

    International Nuclear Information System (INIS)

    Labrie, J.P.; Drewell, N.H.; Ebrahim, N.A.; Lawrence, C.B.; Mason, V.A.; Ungrin, J.; White, B.F.

    1989-01-01

    A family of industrial irradiators is being developed by AECL to cover an electron-beam energy range from 5 to 18 MeV at beam powers between 20 and 250 kW. The IMPELA family of irradiators is designed for push button, reliable operation. The major irradiator components are modular, allowing for later upgrades to meet increased demands in either electron or X-ray mode. Interface between the control system, irradiator availability and dose quality assurance is in conformance with the most demanding specifications. The IMPELA irradiators use a klystron-driven, standing-wave, L-band accelerator structure with direct injection from a rugged, triode electron gun. Direct control of the accelerating field during the beam pulse ensures constant output beam energy, independent of beam power. The first member of the family, the IMPELA 10/50 (10 MeV, 50 kW), is in the final stages of assembly at Chalk River Nuclear Laboratories. The IMPELA 10/50 is constructed around a 3.25 m long, high-power-capacity accelerator structure operated at a duty factor of 5%. Beam loading exceeds 60%. The rf power is provided by a 2 MW/150 kW modulated-anode klystron protected from load mismatches by a circulator. This prototype will be used to demonstrate the reliability and dose uniformity targets of the IMPELA family. Full beam operation of the IMPELA 10/50 is scheduled for early 1989. (orig.)

  18. Decommissioning of AECL Whiteshell laboratories - 16311

    International Nuclear Information System (INIS)

    Koroll, Grant W.; Bilinsky, Dennis M.; Swartz, Randall S.; Harding, Jeff W.; Rhodes, Michael J.; Ridgway, Randall W.

    2009-01-01

    Whiteshell Laboratories (WL) is a Nuclear Research and Test Establishment near Winnipeg, Canada, operated by AECL since the early 1960's and now under decommissioning. WL occupies approximately 4400 hectares of land and employed more than 1000 staff up to the late-1990's, when the closure decision was made. Nuclear facilities at WL included a research reactor, hot cell facilities and radiochemical laboratories. Programs carried out at the WL site included high level nuclear fuel waste management research, reactor safety research, nuclear materials research, accelerator technology, biophysics, and industrial radiation applications. In preparation for decommissioning, a comprehensive environmental assessment was successfully completed [1] and the Canadian Nuclear Safety Commission issued a six-year decommissioning licence for WL starting in 2003 - the first decommissioning licence issued for a Nuclear Research and Test Establishment in Canada. This paper describes the progress in this first six-year licence period. A significant development in 2006 was the establishment of the Nuclear Legacy Liabilities Program (NLLP), by the Government of Canada, to safely and cost effectively reduce, and eventually eliminate the nuclear legacy liabilities and associated risks, using sound waste management and environmental principles. The NLLP endorsed an accelerated approach to WL Decommissioning, which meant advancing the full decommissioning of buildings and facilities that had originally been planned to be decontaminated and prepared for storage-with-surveillance. As well the NLLP endorsed the construction of enabling facilities - facilities that employ modern waste handling and storage technology on a scale needed for full decommissioning of the large radiochemical laboratories and other nuclear facilities. The decommissioning work and the design and construction of enabling facilities are fully underway. Several redundant non-nuclear buildings have been removed and redundant

  19. The AECL study for an intense neutron - generator (technical details)

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, G A; Tunnicliffe, P R

    1966-07-01

    The AECL study for an intense neutron-generator has been in progress for two years. Recently the scientific and technical details and the conceptual designs were compiled in a report supporting proposals addressed to AECL's Board of Directors for further work. The compilation is being issued in this form to permit further discussion of the technical aspects. However readers are asked to appreciate that it was written primarily for an AECL audience, and specifically that those chapters giving tentative information about costs, the rate of investment and similar items have been omitted or modified, many references have been made to interim internal reports in order to complete the local documentation, but these references do not imply that the reports themselves can be made generally available. (author)

  20. The AECL study for an intense neutron - generator (technical details)

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomew, G.A.; Tunnicliffe, P.R

    1966-07-01

    The AECL study for an intense neutron-generator has been in progress for two years. Recently the scientific and technical details and the conceptual designs were compiled in a report supporting proposals addressed to AECL's Board of Directors for further work. The compilation is being issued in this form to permit further discussion of the technical aspects. However readers are asked to appreciate that it was written primarily for an AECL audience, and specifically that those chapters giving tentative information about costs, the rate of investment and similar items have been omitted or modified, many references have been made to interim internal reports in order to complete the local documentation, but these references do not imply that the reports themselves can be made generally available. (author)

  1. The AECL study for an intense neutron - generator (technical details)

    International Nuclear Information System (INIS)

    Bartholomew, G.A.; Tunnicliffe, P.R.

    1966-01-01

    The AECL study for an intense neutron-generator has been in progress for two years. Recently the scientific and technical details and the conceptual designs were compiled in a report supporting proposals addressed to AECL's Board of Directors for further work. The compilation is being issued in this form to permit further discussion of the technical aspects. However readers are asked to appreciate that it was written primarily for an AECL audience, and specifically that those chapters giving tentative information about costs, the rate of investment and similar items have been omitted or modified, many references have been made to interim internal reports in order to complete the local documentation, but these references do not imply that the reports themselves can be made generally available. (author)

  2. Expert panel on hydrogeology; report to AECL Research (1992)

    International Nuclear Information System (INIS)

    Domenico, P.A.; Grisak, G.E.; Schwartz, F.W.

    1995-02-01

    In 1992 AECL Research convened a panel of external hydrogeological experts consisting of P.A. Domenico, G.E. Grisak, and F.W. Schwartz, to review AECL's proposed approach to siting a geological repository in the rocks of the Canadian Shield for the safe disposal of Canada's nuclear fuel wastes. In particular the panel was asked to provide its opinion on 1) the soundness of the technical approach developed to characterize the groundwater flow systems for the purpose of selecting a location for a disposal vault, 2) the validity and effectiveness of the geological case study used to demonstrate the performance assessment methodology based on the hydrogeological conditions observed at the Whiteshell Research Area, and 3) the adequacy of the hydrogeological information that AECL proposes to use in its Environmental Impact Statement (EIS) of the disposal concept. This report presents the findings, conclusions and recommendations of the hydrogeology review panel. The report was submitted to AECL Research in 1992 December. (author). 24 refs., 2 tabs., 4 figs

  3. The year 2000 (Y2k) Programme at AECL

    International Nuclear Information System (INIS)

    Pauksens, J.; Jung, D.

    1998-01-01

    In the nuclear industry we make, in total, very extensive use of digital computers and equipment. While use of dates in our application may not be quite so extensive as in other businesses such as banking or insurance, dates are nonetheless employed, and are important in a variety of applications. Furthermore, date-related problems can sometimes propagate into overall system failures or computer crashes. Digital system or digital infrastructure failure can have serious potential consequences in a power plant, utility, or engineering design office. This in turn can have potential impact on public safety or the reliability of power production and delivery of electrical power to the public. A concerted effort is needed, and is underway by nuclear design organizations, and the nuclear utilities in order to identify and fix or avoid the problems in the short time that remains between now and the Year 2000. AECL have a substantial Year 2000 programme underway, addressing both the infrastructure systems at AECL, and AECL's products and services. High priority is placed, in the programme, on assisting AECL's customers with the Year 2000 issue. The programme, and some of the lesson learned to date, are described in this paper. The relationship to equipment vendors' and customers' Year 2000 programs is explained, and the importance of Year 2000 programmes conducted by the customers, to address systems and equipment which are under their control, is highlighted. (authors)

  4. Evaluation of the in-pile pressure data from instrumented fuel assemblies IFA-431 and IFA-432

    International Nuclear Information System (INIS)

    Bradley, E.R.; Cunningham, M.E.; Lanning, D.D.; Williford, R.E.

    1979-10-01

    This report includes results of the examination of the in-pile pressure data from instrumented test assemblies IFA-431 and 432. The pressure data have been used to estimate the fission gas release fraction as a function of fuel burnup. Included are comparisons of the estimated release functions and those predicted by three fission gas release models using the experimental temperature histories of the fuel rods. These comparisons show that fuel temperature is the primary factor in determining fission gas release and that burnup-enhanced fission gas release is not important in UO 2 fuels irradiated to 1700 GJ/kgU

  5. Controlled drill ampersand blast excavation at AECL's Underground Research Laboratory

    International Nuclear Information System (INIS)

    Kuzyk, G.W.; Onagi, D.P.; Thompson, P.M.

    1996-01-01

    A controlled drill and blast method has been developed and used to excavate the Underground Research Laboratory, a geotechnical facility constructed by Atomic Energy of Canada Limited (AECL) in crystalline rock. It has been demonstrated that the method can effectively reduce the excavation disturbed zone (EDZ) and is suitable for the construction of a used fuel disposal vault in the plutonic rock of the Canadian Shield

  6. Comparison of Wims-Aecl / Dragon / RFSP and MCNP results with Zed-2 measurements for control device worth and reactor kinetics - 037

    International Nuclear Information System (INIS)

    Pencer, J.; Choy Wong, F.; Bromley, B.P.; Atfield, J.; Zeller, M.

    2010-01-01

    This paper summarizes comparisons between MCNP5 and WIMS-AECL / DRAGON / RFSP calculations and experimental results obtained from the Zero Energy Deuterium (ZED-2) critical facility at AECL Chalk River Laboratories. MCNP5 and WIMS-AECL / DRAGON / RFSP were used to calculate reactivity worths for two reactivity devices, a mechanical zone controller (MZC) and shut-off rod (SOR) in a lattice similar to that of the ACR-1000 R . WIMS-AECL / DRAGON / RFSP was also used to obtain kinetics parameters for a transient based on a rod drop of a ZED-2 standby absorber rod (SAR). ZED-2 experiments were performed using 43-element ACR Low Enriched Uranium (ACR-LEU) fuel bundles with H 2 O- or air-cooled fuel bundles arranged in a 24-cm pitch square lattice. Calculations with MCNP5 gave biases in device worths that were within 0.2 mk of measured values, while WIMS-AECL / DRAGON / RFSP gave values that were within 0.3 mk of measured values. Transient analyses using the CERBERUS module within RFSP yielded a total delayed neutron fraction (β) that was within 4% of the value derived by point kinetics analysis of experimental data. The corresponding delayed photo-neutron fraction (β photo-neutron ) from CERBERUS was within 5% of that derived by point kinetics. This study has helped quantify the agreement between calculation and measurement for codes that are used in the safety analysis of the ACR-1000 reactor. Results demonstrate good agreement in code predictions. (authors)

  7. Radiation protection aspects of AECL's retube/refurbishment projects

    International Nuclear Information System (INIS)

    Zhuang, Y.; Boss, C.R.; Pontikakis, N.

    2007-01-01

    In contrast to the construction of a new nuclear reactor, Retube/Refurbishment of nuclear reactors that have been in operation for many years will involve fabrication of a new core in a radiation environment. Careful planning of the radiation protection (RP) program is crucial to ensure the protection of workers and the environment, and the success of the projects. This paper describes the key RP activities currently underway in AECL's Retube/Refurbishment projects, covering RP during retubing tooling and system designs, retubing work planning, retubing operation, and waste transfer and management. The discussion will focus on RP initiatives from engineering design aspects of the projects. (author)

  8. The Atomic Energy of Canada Limited (AECL) employee health study

    International Nuclear Information System (INIS)

    Myers, D.K.; Werner, M.M.

    1985-01-01

    A preliminary examination of records relating to past Chalk River employees provides some reassurance that large numbers of cancer deaths that might be related to occupational radiation exposure do not exist in the groups of employees studied to the end of 1982. The lack of reliable information on deaths of ex-employees who left AECL for other employment prevented the inclusion of this group in this preliminary study. This information will presumably be obtained during the course of the more comprehensive Atomic Energy of Canada Ltd. employee health study. 6 refs

  9. On the difference between DRAGON and WIMS-AECL calculations of the coolant void reactivity

    International Nuclear Information System (INIS)

    Altiparmakov, D.; Roubtsov, D.; Irish, J.D.

    2009-01-01

    A difference in the shape of the burnup dependence of the coolant void reactivity (CVR) has been observed between DRAGON and WIMS-AECL calculations. This paper discusses the root cause of the difference and assesses the impact on burnup and full-core reactor calculations. A Fortran procedure has been developed to run WIMS-AECL as necessary in order to mimic DRAGON burnup calculations with leakage effects included. The comparison of standard WIMS-AECL results and simulated DRAGON results demonstrated that the difference is due to different definitions of CVR. If the same CVR definition is used, then the results of both WIMS-AECL and DRAGON analyses are essentially indistinguishable. The discrepancies in the fuel composition and cell-averaged two-group cross sections that are due to differences in WIMS-AECL and DRAGON leakage treatments are insignificant. (author)

  10. ZZ CANDULIB-AECL, Burnup-Dependent ORIGEN-S Cross-Section Libraries for Candu Reactor Fuels

    International Nuclear Information System (INIS)

    2002-01-01

    1 - Historical background and information: - 28-element fuel cross-section library: Format: Designed for use with the ORIGEN-S isotope generation and depletion code. Materials: Co, Ge, As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Lu, Ta, W, Re, Au, Th, Pa, U, Np, Pu, Am, Cm. Origin: ENDSF, ENDF/B-IV, -V and -VI Weighting spectrum: determined using WIMS-AECL transport code. - 37-element fuel cross-section library: Format: Designed for use with the ORIGEN-S isotope generation and depletion code. Materials: Co, Ge, As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Lu, Ta, W, Re, Au, Th, Pa, U, Np, Pu, Am, Cm. Origin: ENDSF, ENDF/B-IV, -V and -VI Weighting spectrum: determined using WIMS-AECL transport code. In 1995, updated ORIGEN-S cross-section libraries were created as part of a program to upgrade and standardize the computer codes and nuclear data employed for used fuel characterization. This effort was funded through collaboration between Atomic Energy of Canada Limited and the Canadian Nuclear Power Utilities, under the Candu Owners Group (COG). The updated cross sections were generated using the WIMS-AECL lattice code and ENDF/B-V and -VI based data to provide cross section consistency with reactor physics codes. 2 - Application of the data: The libraries in this data collection are designed for characterising used fuel from Candu pressurized heavy water reactors. Two libraries are provided: one for the standard 28-element fuel bundle design, the other for the 37-element fuel bundle design. The libraries were generated for typical reactor operating conditions. The libraries are designed for use with the ORIGEN-S isotope generation and depletion code. 3 - Source and scope of data: The Candu libraries are updated with cross sections from a variety of different sources. Capture

  11. Some highlights of research and development at AECL

    International Nuclear Information System (INIS)

    Langford, W.J.; Rae, H.K.

    1980-06-01

    The research and development programs of AECL have as their goal the strengthening of the knowledge and ability necessary to achieve national objectives in the field of nuclear energy. These objectives include a nuclear reactor system appropriate to Canada's industrial capabilities, now realized, and the extension of that system, through scientific and technological development, to serve the nation's needs for the forseeable future. The Company's programs are carefully integrated and focused to use the available funding to maximum advantage. The research facilities on which the program depends are among the best in the world, and support a full spectrum of research from fundamental nuclear physics to full-scale power reactor component irradiation and testing. In this report it has only been possible to high-light some important facets of the programs in each of the principal areas currently employing our energies. (auth)

  12. AECL's research and development program in environmental science and technology

    International Nuclear Information System (INIS)

    Cornett, R.J.

    1998-07-01

    AECL's radiological research and development (R and D) program encompasses work on sources of radiation exposure, radionuclide transport through the environment and potential impacts on biota and on human health. The application of the radiation protection knowledge and technology developed in this program provides cradle-to-grave management for CANDU and related nuclear technologies. This document provides an overview of the Environmental Science and Technology (ES and T) program which is one of the technical areas of R and D within the radiological R and D program. The ES and T program uses science from three main areas: radiochemistry, mathematical modelling and environmental assessment. In addition to providing an overview of the program, this summary also gives specific examples of recent technical work in each of the three areas. These technical examples illustrate the applied nature of the ES and T program and the close coupling of the program to CANDU customer requirements. (author)

  13. AECL experience with low-level radioactive waste technologies

    International Nuclear Information System (INIS)

    Buckley, L.P.; Charlesworth, D.H.

    1988-08-01

    Atomic Energy of Canada Limited (AECL), as the Canadian government agency responsible for research and development of peaceful uses of nuclear energy, has had experience in handling a wide variety of radioactive wastes for over 40 years. Low-level radioactive waste (LLRW) is generated in Canada from nuclear fuel manufacturers and nuclear power facilities, from medical and industrial uses of radioisotopes and from research facilities. The technologies with which AECL has strength lie in the areas of processing, storage, disposal and safety assessment of LLRW. While compaction and incineration are the predominant methods practised for solid wastes, purification techniques and volume reduction methods are used for liquid wastes. The methods for processing continue to be developed to improve and increase the efficiency of operation and to accommodate the transition from storage of the waste to disposal. Site-specific studies and planning for a LLRW disposal repository to replace current storage facilities are well underway with in-service operation to begin in 1991. The waste will be disposed of in an intrusion-resistant underground structure designed to have a service life of over 500 years. Beyond this period of time the radioactivity in the waste will have decayed to innocuous levels. Safety assessments of LLRW disposal are performed with the aid of a series of interconnected mathematical models developed at Chalk River specifically to predict the movement of radionuclides through and away from the repository after its closure and the subsequent health effects of the released radionuclides on the public. The various technologies for dealing with radioactive wastes from their creation to disposal will be discussed. 14 refs

  14. Rationalization and future planning for AECL's research reactor capability

    International Nuclear Information System (INIS)

    Slater, J.B.

    1990-01-01

    AECL's research reactor capability has played a crucial role in the development of Canada's nuclear program. All essential concepts for the CANDU reactors were developed and tested in the NRX and NRU reactors, and in parallel, important contributions to basic physics were made. The technical feasibility of advanced fuel cycles and of the organic-cooled option for CANDU reactors were also demonstrated in the two reactors and the WR-1 reactor. In addition, an important and growing radio-isotope production industry was established and marketed on a world-wide basis. In 1984, however, it was recognized that a review and rationalization of the research reactor capability was required. The commercial success of the CANDU reactor system had reduced the scope and size of the required development program. Limited research and development funding and competition from other research facilities and programs, required that the scope be reduced to a support basis essential to maintain strategic capability. Currently, AECL, is part-way through this rationalization program and completion should be attained during 1992/93 when the MAPLE reactor is operational and decisions on NRX decommissioning will be made. A companion paper describes some of the unique operational and maintenance problems which have resulted from this program and the solutions which have been developed. Future planning must recognize the age of the NRU reactor (currently 32 years) and the need to plan for eventual replacement. Strategy is being developed and supporting studies include a full technical assessment of the NRU reactor and the required age-related upgrading program, evaluation of the performance characteristics and costs of potential future replacement reactors, particularly the advanced MAPLE concept, and opportunities for international co-operation in developing mutually supportive research programs

  15. A study of the mortality of AECL employees. V

    International Nuclear Information System (INIS)

    Gribbin, M.A.; Howe, G.R.; Weeks, J.L.

    1992-09-01

    A study has been underway since 1980 on the mortality of past and present AECL employees. The study population consists of 13,491 persons, 9997 males and 3494 females, for a total of 262,403.5 person-years at risk. During the period 1950-1985, 1299 deaths occurred in this population. The number of female deaths (121) is too few for detailed analysis, but the 1178 deaths in the male population represent a useful basis for this study. The present report examines mortality patterns in the AECL cohort between 1950 and 1985 by comparing the observed mortality with that expected in the general population for three groups of workers: those with no exposure, those with up to 50 mSv, and those with more than 50 mSv. Comparisons among the three groups of employees are discussed. The number of deaths is fewer than would be expected on the basis of general population statistics for both males who were exposed to ionizing radiation and those who were not exposed. The findings were similar for the 'all cancer' and 'all other deaths' groupings. In the group of exposed males, elevated Standardized Mortality Ratios (SMRs) are seen for non-Hodgkin's lymphoma and for buccal cavity, rectum and rectosigmoid junction, and prostate cancers. There are elevated SMRs for lymphatic and myeloid leukemias and for large intestine, prostate, brain and biliary system cancers in the 'unexposed' male group. The number of cases identified in all of these cancers is small and the confidence intervals are wide, such that none of the elevated SMRs is statistically significant. The report compares the findings of this study with those of similar studies published in the past decade. (Author) (28 tabs., 33 refs., 2 figs.)

  16. Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

    International Nuclear Information System (INIS)

    Sabourin, G.

    1998-01-01

    This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

  17. Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

    Energy Technology Data Exchange (ETDEWEB)

    Sabourin, G. [Atomic Energy of Canada Limited, Montreal, PQ (Canada)

    1998-07-01

    This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

  18. AECL's underground research laboratory: technical achievements and lessons learned

    International Nuclear Information System (INIS)

    Ohta, M.M.; Chandler, N.A.

    1997-03-01

    During the development of the research program for the Canadian Nuclear Fuel Waste Management Program in the 1970's, the need for an underground facility was recognized. AECL constructed an Underground Research Laboratory (URL) for large-scale testing and in situ engineering and performance-assessment-related experiments on key aspects of deep geological disposal in a representative geological environment. Ale URL is a unique geotechnical research and development facility because it was constructed in a previously undisturbed portion of a granitic pluton that was well characterized before construction began, and because most of the shaft and experimental areas are below the water table. The specific areas of research, development and demonstration include surface and underground characterization; groundwater and solute transport; in situ rock stress conditions; temperature and time-dependent deformation and failure characteristics of rock; excavation techniques to minimize damage to surrounding rock and to ensure safe working conditions; and the performance of seals and backfills. This report traces the evolution of the URL and summarizes the technical achievements and lessons learned during its siting, design and construction, and operating phases over the last 18 years. (author)

  19. Development, irradiation testing and PIE of UMo fuel at AECL

    International Nuclear Information System (INIS)

    Sears, D.F.

    2005-01-01

    This paper reviews recent U-Mo dispersion fuel development, irradiation testing and postirradiation examination (PIE) activities at AECL. Low-enriched uranium fuel alloys and powders have been fabricated at Chalk River Labs, with compositions ranging from U-7Mo to U-10Mo. The bulk alloys and powders were characterized using optical and scanning electron microscopy, chemical analysis, X-ray diffraction and neutron diffraction analysis. The analyses confirmed that the powders were of high quality, and in the desired gamma phase. Subsequently, kilogram quantities of DU-Mo and LEU-Mo powder have been manufactured for commercial customers. Mini-elements have been fabricated with LEU-7Mo and LEU-10Mo dispersed in aluminum, with a nominal loading of 4.5 gU/cm 3 . These have been irradiated in the NRU reactor at linear powers up to 100 kW/m. The mini-elements achieved 60 atom% 235 U burnup in 2004 March, and the irradiation is continuing to a planned discharge burnup of 80 atom% 235 U. Interim PIE has been conducted on mini-elements that were removed after 20 atom% 235 U burnup. The PIE results are presented in this paper. (author)

  20. Evaluation of AECL catalysts for hydrogen fuel-cell applications. Paper no. IGEC-1-073

    International Nuclear Information System (INIS)

    Li, J.; Suppiah, S.; Li, H.; Kutchcoskie, K.J.; Strikwerda, S.

    2005-01-01

    AECL has been engaged in the promotion of the nuclear-hydrogen economy, which envisions that hydrogen fuel cells will generate power using hydrogen as fuel produced by nuclear energy. Since AECL's catalysts developed for the production, upgrading and detritiation of heavy water are very similar to commercial fuel-cell catalysts, a program was initiated to evaluate AECL catalysts for fuel-cell applications. As a first step in this effort, a half-cell test facility was set up to characterize the performance of catalysts for hydrogen fuel cells. This paper outlines the results obtained from cathodic reduction of oxygen in a 0.5 M sulphuric acid solution on a rotating disc electrode at 65 o C. The performance of the catalysts was characterized using standard electrochemical methods including cyclic voltammetry, Voltammogram/Tafel plots and short-term stability plots. Several monometallic Pt and Pt-based bimetallic catalysts were tested and compared with a commercially available catalyst for fuel-cell applications. AECL's monometallic Pt catalysts showed comparable or better activities than commercial catalysts with similar Pt loading. An AECL Pt-based bimetallic catalyst has shown superior performance to a monometallic Pt catalyst with similar Pt loading. Evaluation of various catalyst formulations is ongoing on the half-cell facility at AECL. Further investigation of promising catalysts identified from half-cell test is also being carried out in single fuel cell on test stations under normal fuel-cell operating conditions. (author)

  1. DEMONSTRATION SOLIDIFICATION TESTS CONDUCTED ON RADIOACTIVELY CONTAMINATED ORGANIC LIQUIDS AT THE AECL WHITESHELL LABORATORIES

    International Nuclear Information System (INIS)

    Ryz, R. A.; Brunkow, W. G.; Govers, R.; Campbell, D.; Krause, D.

    2002-01-01

    The AECL, Whiteshell Laboratory (WL) near Pinawa Manitoba, Canada, was established in the early 1960's to carry out AECL research and development activities for higher temperature versions of the CANDU(reg s ign) reactor. The initial focus of the research program was the Whiteshell Reactor-1 (WR-1) Organic Cooled Reactor (OCR) that began operation in 1965. The OCR program was discontinued in the early 1970's in favor of the successful heavy-water-cooled CANDU system. WR-1 continued to operate until 1985 in support of AECL nuclear research programs. A consequence of the Federal government's recent program review process was AECL's business decision to discontinue research programs and operations at the Whiteshell Laboratories and to consolidate its' activities at the Chalk River Laboratories. As a result, AECL received government concurrence in 1998 to proceed to plan actions to achieve closure of WL. The planning actions now in progress address the need to safely and effectively transition the WL site from an operational state, in support of AECL's business, to a shutdown and decommissioned state that meets the regulatory requirements for a licensed nuclear site. The decommissioning program that will be required at WL is unique within AECL and Canada since it will need to address the entire research site rather than individual facilities declared redundant. Accordingly, the site nuclear facilities are being systematically placed in a safe shutdown state and planning for the decommissioning work to place the facilities in a secure monitoring and surveillance state is in progress. One aspect of the shutdown activities is to deal with the legacy of radioactively contaminated organic liquid wastes. Use of a polymer powder to solidify these organic wastes was identified as one possibility for improved interim storage of this material pending final disposition

  2. AECL's concept for the disposal of nuclear fuel waste and the importance of its implementation

    International Nuclear Information System (INIS)

    Allan, C.J.

    1993-07-01

    Since 1978, Canada has been investigating a concept for permanently dealing with the nuclear fuel waste from Canadian CANDU (Canada Deuterium Uranium) nuclear generating stations. The concept is based on disposing of the waste in a vault excavated 500 to 1000 m deep in intrusive igneous rock of the Canadian Shield. AECL Research will soon be submitting an environmental impact statement (EIS) on the concept for review by a Panel through the federal environmental assessment and review process (EARP). In accordance with AECL Research's mandate and in keeping with the detailed requirements of the review Panel, AECL Research has conducted extensive studies on a wide variety of technical and socio-economic issues associated with the concept. If the concept is accepted, we can and should continue our responsible approach and take the next steps towards constructing a disposal facility for Canada's used nuclear fuel waste

  3. AECL's participation in the commissioning of Point Lepreau generating station unit 1

    International Nuclear Information System (INIS)

    Chawla, S.; Singh, K.; Yerramilli, S.

    1983-05-01

    Support from Atomic Energy of Canada Ltd. (AECL) to Point Lepreau during the commissioning program has been in the form of: seconded staff for commissioning program management, preparation of commissioning procedures, and hands-on commissioning of several systems; analysis of test results; engineering service for problem solving and modifications; design engineering for changes and additions; procurement of urgently-needed parts and materials; technological advice; review of operational limits; interpretation of design manuals and assistance with and preparation of submissions to regulatory authorities; and development of equipment and procedures for inspection and repairs. This, together with AECL's experience in the commissioning of other 600 MWe stations, Douglas Point and Ontario Hydro stations, provides AECL with a wide range of expertise for providing operating station support services for CANDU stations

  4. Follow-up of AECL employees involved in the decontamination of NRU in 1958

    International Nuclear Information System (INIS)

    Werner, M.M.; Myers, D.K.; Morrison, D.P.

    1982-09-01

    In May 1958 the NRU reactor hall was badly contaminated by a damaged fuel rod that broke apart during its removal from the reactor. Radioactive fission products were spread around the reactor hall and into adjacent areas when a piece of the fuel rod fell into the maintenance pit and burned. AECL staff and others completed the decontamination in 2 1/2 months. This paper reports the results of a follow-up study of the AECL participants. No statistically significant increases in deaths from cancer or other diseases were found in this group

  5. Planning a new research reactor for AECL: The MAPLE-MTR concept

    International Nuclear Information System (INIS)

    Lee, A.G.; Lidstone, R.F.; Donnelly, J.V.

    1992-01-01

    AECL Research is assessing its needs and options for future irradiation research facilities. A planning team has been assembled to identify the irradiation requirements for AECL's research programs and compile options for satisfying the irradiation requirements. The planning team is formulating a set of criteria to evaluate the options and will recommend a plan for developing an appropriate research facility. Developing the MAPLE Materials Test Reactor (MAPLE-MTR) concept to satisfy AECL's irradiation requirements is one option under consideration by the planning team. AECL is undertaking this planning phase because the NRU reactor is 35 years old and many components are nearing the end of their design life. This reactor has been a versatile facility for proof testing CANDU components and fuel designs because the CANDU irradiation environment was simulated quite well. However, the CANDU design has matured and the irradiation requirements have changed. Future research programs will emphasize testing CANDU components near or beyond their design limits. To provide these irradiation conditions, the NRU reactor needs to be upgraded. Upgrading and refurbishing the NRU reactor is being considered, but the potentially large costs and regulatory uncertainties make this option very challenging. AECL is also developing the MAPLE-MTR concept as a potential replacement for the NRU reactor. The MAPLE-MTR concept starts from the recent MAPLE-X10 design and licensing experience and adapts this technology to satisfy the primary irradiation requirements of AECL's research programs. This approach should enable AECL to minimize the need for major advances in nuclear technology (e.g., fuel design, heat transfer). The preliminary considerations for developing the MAPLE-MTR concept are presented in this report. A summary of AECL's research programs is presented along with their irradiation requirements. This is followed by a description of safety criteria that need to be taken into

  6. Status and Plans for work on pressure tube creep at AECL

    International Nuclear Information System (INIS)

    Bickel, Grant A.

    2013-01-01

    AECL research goals: • Develop empirical models to: – regress out operating conditions/extrinsic factors – rank relative strain behavior of measured in-service pressure tubes; • Correlate the ranked strains to manufacturing variables and the microstructure to: – Develop mechanistic insights – Optimize manufacturing/microstructure for improved pressure tube performance

  7. Advanced fuel development at AECL: What does the future hold for CANDU fuels/fuel cycles?

    Energy Technology Data Exchange (ETDEWEB)

    Kupferschmidt, W.C.H. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2013-07-01

    This paper outlines advanced fuel development at AECL. It discusses expanding the limits of fuel utilization, deploy alternate fuel cycles, increase fuel flexibility, employ recycled fuels; increase safety and reliability, decrease environmental impact and develop proliferation resistant fuel and fuel cycle.

  8. PEAR code review

    International Nuclear Information System (INIS)

    De Wit, R.; Jamieson, T.; Lord, M.; Lafortune, J.F.

    1997-07-01

    As a necessary component in the continuous improvement and refinement of methodologies employed in the nuclear industry, regulatory agencies need to periodically evaluate these processes to improve confidence in results and ensure appropriate levels of safety are being achieved. The independent and objective review of industry-standard computer codes forms an essential part of this program. To this end, this work undertakes an in-depth review of the computer code PEAR (Public Exposures from Accidental Releases), developed by Atomic Energy of Canada Limited (AECL) to assess accidental releases from CANDU reactors. PEAR is based largely on the models contained in the Canadian Standards Association (CSA) N288.2-M91. This report presents the results of a detailed technical review of the PEAR code to identify any variations from the CSA standard and other supporting documentation, verify the source code, assess the quality of numerical models and results, and identify general strengths and weaknesses of the code. The version of the code employed in this review is the one which AECL intends to use for CANDU 9 safety analyses. (author)

  9. Co-operative projects with AECL in the fields of hydrogeology and geochemistry

    International Nuclear Information System (INIS)

    1985-01-01

    The report covers collaborative study with Atomic Energy of Canada Limited on geological aspects of waste disposal in crystalline rocks. A field test of the sinusoidal hydraulic pressure pulse method was carried out at the URL site to try to define hydraulic properties of major horizontal fractures. The trials were generally successful and observable sine and square wave signals were transmitted. Owing to the limited scale of the programme, and some equipment problems, the results proved difficult to interpret, although the speed and flexibility of the method was demonstrated. A second aspect of collaboration was to be the field comparison of the AECL and NERC/BGS borehole geochemical probes. In the event, the AECL probe development programme was curtailed and a Swedish design selected for purchase. Effort thus switched to technical comparison of the SGAB probe with the NERC/BGS design. Since both are still at various development points the collaboration was limited to technical exchange. The results are presented. (author)

  10. AECL hot-cell facilities and post-irradiation examination services

    International Nuclear Information System (INIS)

    Schankula, M.H.; Plaice, E.L.; Woodworth, L.G.

    1995-01-01

    This paper presents an overview of the post-irradiation examination (PIE) services available at AECL's hot-cell facilities (HCF). The HCFs are used primarily to provide PIE support for operating CANDU power reactors in Canada and abroad, and for the examination of experimental fuel bundles and core components irradiated in research reactors at the Chalk River Laboratories (CRL) and off-shore. A variety of examinations and analysis are performed ranging from non-destructive visual and dimensional inspections to detailed optical and scanning electron microscopic examinations. Several hot cells are dedicated to mechanical property testing of structural materials and to determine the fitness-for-service of reactor core components. Facility upgrades and the development of innovative examination techniques continue to improve AECL's PIE capabilities. (author)

  11. AECL hot-cell facilities and post-irradiation examination services

    International Nuclear Information System (INIS)

    Schankula, M.H.; Plaice, E.L.; Woodworth, L.G.

    1998-04-01

    This paper presents an overview of the post-irradiation examination (PIE) services available at AECL's hot-cell facilities (HCF). The HCFs are used primarily to provide PIE support for operating CANDU power reactors in Canada and abroad, and for the examination of experimental fuel bundles and core components irradiated in research reactors at the Chalk River Laboratories (CRL) and off-shore. A variety of examinations and analyses are performed ranging from non-destructive visual and dimensional inspections to detailed optical and scanning electron microscopic examinations. Several hot cells are dedicated to mechanical property testing of structural materials and to determine the fitness-for-service of reactor core components. Facility upgrades and the development of innovative examination techniques continue to improve AECL's PIE capabilities. (author)

  12. Microbial analysis of the buffer/container experiment at AECL's underground research laboratory

    International Nuclear Information System (INIS)

    Stroes-Gascoyne, S.

    1996-07-01

    The Buffer/Container Experiment (BCE) was carried out at AECL's Underground Research Laboratory (URL) for 2.5 years to examine the in situ performance of compacted buffer material in a single emplacement borehole under vault-relevant conditions. During decommissioning of this experiment, numerous samples were taken for microbial analysis to determine if the naturally present microbial population in buffer material survived the conditions (i.e., compaction, heat and desiccation) in the BCE and to determine which group(s) of microorganisms would be dominant in such a simulated vault environment. Such knowledge will be very useful in assessing the potential effects of microbial activity on the concept for deep disposal of Canada's nuclear fuel waste, proposed by AECL. 46 refs., 31 tabs., 35 figs

  13. Antibiotics from bacillus subtilis AECL90 - effect of trace elements and carbohydrates on antibiotic production

    International Nuclear Information System (INIS)

    Malik, M.A.; Shaukat, G.A.; Ahmed, M.S.

    1990-01-01

    Three types of antibiotics S, X and F characteristically bioactive against staphylococcic, xanthomonas and fungi are elaborated by Bacillus Subtilis AECL 69 when grown in molasses peptone malt extract sucrose. No antibiotic production was observed when molasses was omitted from the growth medium. A mineral salt mixture was devised that could replace molasses and restore the production of antibiotics. Influence of various carbohydrates on the production of antibiotics was also studied. Mannose and mannitol had inhibitory effect on the antibiotic production. (author)

  14. Comparison of MCNP and WIMS-AECL/RFSP calculations against critical heavy water experiments in ZED-2 with CANFLEX-LVRF and CANFLEX-LEU fuels

    International Nuclear Information System (INIS)

    Bromley, B. P.; Watts, D. G.; Pencer, J.; Zeller, M.; Dweiri, Y.

    2009-01-01

    This paper summarizes calculations of MCNP5 and WIMS-AECL/RFSP compared against measurements in coolant void substitution experiments in the ZED-2 critical facility with CANFLEX R-LEU/RU (Low Enriched Uranium, Recovered Uranium) reference fuels and CANFLEX-LVRF (Low Void Reactivity Fuel) test fuel, and H 2 O/air coolants. Both codes are tested for the prediction of the change in reactivity with complete voiding of all fuel channels, and that for a checkerboard voiding pattern. Understanding these phenomena is important for the ACR-1000 R reactor. Comparisons are also made for the prediction of the axial and radial neutron flux distributions, as measured by copper foil activation. The experimental data for these comparisons were obtained from critical mixed lattice / substitution experiments in AECL's ZED-2 critical facility using CANFLEX-LEU/RU and CANFLEX-LVRF fuel in a 24-cm square lattice pitch at 25 degrees C. Substitution analyses were performed to isolate the properties (buckling, bare critical lattice dimensions) of the CANFLEX-LVRF fuel. This data was then used to further test the lattice physics codes. These comparisons establish biases/uncertainties and errors in the calculation of k eff , coolant void reactivity, checkerboard coolant void reactivity, and flux distributions. Results show small to modest biases in void reactivity and very good agreement for flux distributions. The importance of boundary conditions and the modeling of un-moderated fuel in the critical experiments are demonstrated. This comparison study provides data that supports code validation and gives good confidence in the reactor physics tools used in the design and safety analysis of the ACR-1000 reactor. (authors)

  15. AECL strategy for surface-based investigations of potential disposal sites and the development of a geosphere model for a site

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, S H; Brown, A; Davison, C C; Gascoyne, M; Lodha, G S; Stevenson, D R; Thorne, G A; Tomsons, D [AECL Research, Whiteshell Labs., Pinawa, MB (Canada)

    1994-05-01

    The objective of this report is to summarize AECL`s strategy for surface-based geotechnical site investigations used in screening and evaluating candidate areas and candidate sites for a nuclear fuel waste repository and for the development of geosphere models of sites. The report is one of several prepared by national nuclear fuel waste management programs for the Swedish Nuclear Fuel and Waste Management Co. (SKB) to provide international background on site investigations for SKB`s R and D programme on siting.The scope of the report is limited to surface-based investigations of the geosphere, those done at surface or in boreholes drilled from surface. The report discusses AECL`s investigation strategy and the methods proposed for use in surface-based reconnaissance and detailed site investigations at potential repository sites. Site investigations done for AECL`s Underground Research Laboratory are used to illustrate the approach. The report also discusses AECL`s strategy for developing conceptual and mathematical models of geological conditions at sites and the use of these models in developing a model (Geosphere Model) for use in assessing the performance of the disposal system after a repository is closed. Models based on the site data obtained at the URL are used to illustrate the approach. Finally, the report summarizes the lessons learned from AECL`s R and D program on site investigations and mentions some recent developments in the R and D program. 120 refs, 33 figs, 7 tabs.

  16. The use of HANDIDET{reg_sign} non-electric detonator assemblies to reduce blast-induced overpressure at AECL`s Underground Research Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Onagi, D.P.; Keith, S.G.; Kuzyk, G.W. [AECL, Pinawa, Manitoba (Canada). Underground Research Lab.; Proudfoot, D.F. [ICI Explosives Canada, North Delta, British Columbia (Canada)

    1996-12-01

    A number of aspects of the Canadian concept for nuclear fuel waste disposal are being assessed by Atomic Energy of Canada Limited (AECL) in a series of experiments at its Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, Canada. One of the major objectives of the work being carried out at the URL is to develop and evaluate the methods and technology to ensure safe, permanent disposal of Canada`s nuclear fuel waste. In 1994, AECL excavated access tunnels and a laboratory room for the Quarried Block Fracture Migration Experiment (QBFME) at the 240 Level of the URL. This facility will be used to study the transport of radionuclides in natural fractures in quarried blocks of granite under in-situ groundwater conditions. The experiment is being carried out under a cooperative agreement with the Japan Atomic Energy Research Institute. The excavation of the QBFME access tunnels and laboratory was carried out using controlled blasting techniques that minimized blast-induced overpressure which could have damaged or interrupted other ongoing experiments in the vicinity. The majority of the blasts used conventional long delay non-electric detonators but a number of blasts were carried out using HANDIDET 250/6000 non-electric long delay detonator assemblies and HTD{reg_sign} non-electric short delay trunkline detonator assemblies. The tunnel and laboratory excavation was monitored to determine the levels of blast-induced overpressure. This paper describes the blasting and monitoring results of the blasts using HANDIDET non-electric detonator assemblies and the effectiveness of these detonators in reducing blast-induced overpressure.

  17. Sensitivity of 238U resonance absorption to library multigroup structure as calculated by WIMS-AECL

    International Nuclear Information System (INIS)

    Laughton, P.J.; Donnelly, J.V.

    1995-01-01

    In simulations of the TRX-1 experimental lattice, WIMS-AECL overpredicts, relative to MCNP, resonance absorption in neutron-energy groups containing the three large, low-lying resonances of 238 U when a standard ENDF/B-V-based library is used. A total excess in these groups of 4.0 neutron captures by 238 U per thousand fission neutrons has been observed. Similar comparisons are made in this work for the MIT-4 experimental lattice and simplified CANDU lattice cells containing 37-element fuel, with and without heavy-water coolant. Eleven different 89-group cross-section libraries were constructed for WIMS-AECL from ENDF/B-V data: only the neutron-energy-group boundaries used in generating multigroup cross sections and the Goldstein-Cohen correction factors differ from one library to the next. The first library uses the original 89-group structure, and the other ten involve energy groups of varying widths centred on the three large, low-lying resonances of 238 U. For TRX-1, some reduction in total discrepancy in 238 U capture can be achieved by using a new structure, although the improvement is small. The discrepancies in 238 U capture are of the same order for the MIT-4 case as those observed for TRX-1 for both the original group structure and the ten new structures. The WIMS-AECL calculation of 238 U resonance absorption in the same ranges of energy for the simplified CANDU 37-element lattice are in better agreement with MCNP than they are for TRX-1 and MIT-4: when the original structure is used, WIMS-AECL underpredicts total capture rate by 238 U in the energy range of interest by only 0.56 per thousand fission neutrons (coolant present) and 0.88 per thousand fission neutrons (voided coolant channel). The discrepancies are reduced when some of the new structures are used. For almost all of the cases considered here-TRX-1, MIT-4 and CANDU with coolant-better group-by-group agreement of 238 U capture around the 6.67-eV resonance is achieved by using a new library

  18. Implementing the AECL decommissioning quality assurance program at the Chalk River and Whiteshell Laboratories

    International Nuclear Information System (INIS)

    Colotelo, C.A.; Attas, E.M.; Stephens, M.E.

    2006-01-01

    This paper describes the approach and progress in developing, implementing and maintaining a quality assurance (QA) program for decommissioning at the nuclear facilities managed by Atomic Energy of Canada Limited (AECL). Decommissioning activities conducted by AECL are varied in nature, so the QA program must provide adequate flexibility, while maintaining consistency with accepted quality standards. Well-written documentation adhering to the applicable decommissioning standards is a key factor. Manager commitment and input during the writing of the documentation are also important to ensure relevance of the QA program and effectiveness of implementation. Training in the use of the quality assurance plan and procedures is vital to the understanding of the QA program. Beyond the training aspect there is a need for the quality assurance program to be supported by a QA subject expert who is able to advise the group in implementing the Quality Program with consistency over the range of decommissioning work activities and to provide continual assessment of the quality assurance program for efficiency and effectiveness, with a concomitant continuous improvement process. (author)

  19. Radiochemistry Lab Decommissioning and Dismantlement. AECL, Chalk River Labs, Ontario, Canada

    International Nuclear Information System (INIS)

    Kenny, Stephen

    2008-01-01

    Atomic Energy of Canada (AECL) was originally founded in the mid 1940's to perform research in radiation and nuclear areas under the Canadian Defense Department. In the mid 50's The Canadian government embarked on several research and development programs for the development of the Candu Reactor. AECL was initially built as a temporary site and is now faced with many redundant buildings. Prior to 2004 small amounts of Decommissioning work was in progress. Many reasons for deferring decommissioning activities were used with the predominant ones being: 1. Reduction in radiation doses to workers during the final dismantlement, 2. Development of a long-term solution for the management of radioactive wastes in Canada, 3. Financial constraints presented by the number of facilities shutdown that would require decommissioning funds and the absence of an approved funding strategy. This has led to the development of a comprehensive decommissioning plan that is all inclusive of AECL's current and legacy liabilities. Canada does not have a long-term disposal site; therefore waste minimization becomes the driving factor behind decontamination for decommissioning before and during dismantlement. This decommissioning job was a great learning experience for decommissioning and the associated contractors who worked on this project. Throughout the life of the project there was a constant focus on waste minimization. This focus was constantly in conflict with regulatory compliance primarily with respect to fire regulations and protecting the facility along with adjacent facilities during the decommissioning activities. Discrepancies in historical documents forced the project to treat every space as a contaminated space until proven differently. Decommissioning and dismantlement within an operating site adds to the complexity of the tasks especially when it is being conducted in the heart of the plant. This project was very successful with no lost time accidents in over one hundred

  20. Decommissioning of AECL Whiteshell Laboratories: progress from first five years of legacy funding

    International Nuclear Information System (INIS)

    Swartz, R.S.; Bilinsky, D.M.; Harding, J.W.; Ridgway, W.R.

    2011-01-01

    In 2006, the Government of Canada adopted a new long-term strategy to deal with the nuclear legacy liabilities and initiated a five-year start-up phase. The objective is to safely and cost-effectively reduce these liabilities, and associated risks, based on sound waste management and environmental principles in the best interests of Canadians. AECL's Whiteshell Laboratories is part of the long-term strategy and decommissioning activities are underway. Several redundant non-nuclear buildings have been removed/decommissioned, and redundant nuclear facilities (hot cell facilities, radiochemical laboratories) are being decontaminated and prepared for demolition. This paper describes the progress in the first five-year funding period (2006 April to 2011 March). (author)

  1. AECL R and D's role in promoting nuclear research and education

    International Nuclear Information System (INIS)

    Sadhankar, R.

    2009-01-01

    Nuclear renaissance has created new opportunities for new technology development and has also brought along the challenge of meeting the growing demand of trained personnel in the nuclear science and engineering. Towards meeting this challenge, AECL R and D organization is actively promoting and supporting the creation of nuclear research capabilities at the universities and also effectively leveraging the R and D at the universities. It has also put in place several new initiatives to attract and develop the talented young people for careers in nuclear science and engineering. This paper describes various interactions and collaborations with the universities that supports the nuclear R and D at the universities and develop highly qualified personnel for the future nuclear R and D needs. (author)

  2. Fretting wear of steam generator tubes: high-temperature tests on AECL rig

    International Nuclear Information System (INIS)

    Guerout, F.; Zbinden, M.

    1993-07-01

    The R and DD has undertaken the study of fretting-wear of Alloy 600 S.G. tubes which occurs by contact with migrating items. The test series was performed in Canada at AECL Research (Atomic Energy of Canada Limited) as part of an exchange program. Four types of configuration were envisaged: a tube-to-drilled hole support contact which provides reference results and three types of tube-to-support contacts which simulate the tube fretting-wear induced by a welding rod, a threaded rod and a knife-edge rod support. This programme is completed by the study of the contact between a S.G. tube and a neighbouring S.G. tube which has been broken after plugging. (authors). 1 tab., 3 refs

  3. Final report of the AECL/SKB Cigar Lake analog study

    International Nuclear Information System (INIS)

    Cramer, J.

    1994-05-01

    The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The Cigar Lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. The study of these natural structures and processes provides valuable insight toward the eventual design and site selection of a nuclear fuel waste repository. The main feature of this analog is the absence of any indication on the surface of the rich uranium ore 450 m below. This indicates that the combination of natural barriers has been effective in isolating the uranium ore from the surface environment. More specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar Lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summery of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety

  4. Final report of the AECL/SKB Cigar Lake analog study

    International Nuclear Information System (INIS)

    Cramer, J.J.

    1994-07-01

    The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The uranium mineralization, consisting primarily of uraninite (UO 2 ), is surrounded by a clay-rich halo in both sandstone and basement rocks, and remains extremely well preserved and intact. The average grade of the mineralization is ∼ 8 wt.% U; locally grades are as high as ∼ 55 wt.%U. The Cigar lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. Specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summary of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety assessment of the Canadian, Swedish and United States disposal concepts. 15 refs., 25 figs., 55 tabs

  5. International standard problem (ISP) no. 41 follow up exercise: Containment iodine computer code exercise: parametric studies

    Energy Technology Data Exchange (ETDEWEB)

    Ball, J.; Glowa, G.; Wren, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Ewig, F. [GRS Koln (Germany); Dickenson, S. [AEAT, (United Kingdom); Billarand, Y.; Cantrel, L. [IPSN (France); Rydl, A. [NRIR (Czech Republic); Royen, J. [OECD/NEA (France)

    2001-11-01

    This report describes the results of the second phase of International Standard Problem (ISP) 41, an iodine behaviour code comparison exercise. The first phase of the study, which was based on a simple Radioiodine Test Facility (RTF) experiment, demonstrated that all of the iodine behaviour codes had the capability to reproduce iodine behaviour for a narrow range of conditions (single temperature, no organic impurities, controlled pH steps). The current phase, a parametric study, was designed to evaluate the sensitivity of iodine behaviour codes to boundary conditions such as pH, dose rate, temperature and initial I{sup -} concentration. The codes used in this exercise were IODE(IPSN), IODE(NRIR), IMPAIR(GRS), INSPECT(AEAT), IMOD(AECL) and LIRIC(AECL). The parametric study described in this report identified several areas of discrepancy between the various codes. In general, the codes agree regarding qualitative trends, but their predictions regarding the actual amount of volatile iodine varied considerably. The largest source of the discrepancies between code predictions appears to be their different approaches to modelling the formation and destruction of organic iodides. A recommendation arising from this exercise is that an additional code comparison exercise be performed on organic iodide formation, against data obtained front intermediate-scale studies (two RTF (AECL, Canada) and two CAIMAN facility, (IPSN, France) experiments have been chosen). This comparison will allow each of the code users to realistically evaluate and improve the organic iodide behaviour sub-models within their codes. (author)

  6. International standard problem (ISP) no. 41 follow up exercise: Containment iodine computer code exercise: parametric studies

    International Nuclear Information System (INIS)

    Ball, J.; Glowa, G.; Wren, J.; Ewig, F.; Dickenson, S.; Billarand, Y.; Cantrel, L.; Rydl, A.; Royen, J.

    2001-11-01

    This report describes the results of the second phase of International Standard Problem (ISP) 41, an iodine behaviour code comparison exercise. The first phase of the study, which was based on a simple Radioiodine Test Facility (RTF) experiment, demonstrated that all of the iodine behaviour codes had the capability to reproduce iodine behaviour for a narrow range of conditions (single temperature, no organic impurities, controlled pH steps). The current phase, a parametric study, was designed to evaluate the sensitivity of iodine behaviour codes to boundary conditions such as pH, dose rate, temperature and initial I - concentration. The codes used in this exercise were IODE(IPSN), IODE(NRIR), IMPAIR(GRS), INSPECT(AEAT), IMOD(AECL) and LIRIC(AECL). The parametric study described in this report identified several areas of discrepancy between the various codes. In general, the codes agree regarding qualitative trends, but their predictions regarding the actual amount of volatile iodine varied considerably. The largest source of the discrepancies between code predictions appears to be their different approaches to modelling the formation and destruction of organic iodides. A recommendation arising from this exercise is that an additional code comparison exercise be performed on organic iodide formation, against data obtained front intermediate-scale studies (two RTF (AECL, Canada) and two CAIMAN facility, (IPSN, France) experiments have been chosen). This comparison will allow each of the code users to realistically evaluate and improve the organic iodide behaviour sub-models within their codes. (author)

  7. Qualification of FEAST 3.0 and FEAT 4.0 computer codes

    International Nuclear Information System (INIS)

    Xu, Z.; Lai, L.; Sim, K.-S.; Huang, F.; Wong, B.

    2005-01-01

    FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. FEAST models the thermo-elastic, thermo-elasto-plastic and creep deformations in CANDU fuel. FEAT (Finite Element Analysis for Temperature) is another AECL computer code and is used to assess the thermal integrity of fuel elements. FEAT models the steady-state and transient heat flows in CANDU fuel, under conditions such as flux depression, end flux peaking, temperature-dependent thermal conductivity, and non-uniform time-dependent boundary conditions. Both computer programs are used in design and qualification analyses of CANDU fuel. Formal qualifications (including coding verification and validation) of both codes were performed, in accordance with AECL software quality assurance (SQA) manual and procedures that are consistent with CSA N286.7-99. Validation of FEAST 3.0 shows very good agreement with independent analytical solutions or measurements. Validation of FEAT 4.0 also shows very good agreement with independent WIMS-AECL calculations, analytical solutions, ANSYS calculations and measurement. (author)

  8. Qualification of FEAST 3.0 and FEAT 4.0 computer codes

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Lai, L.; Sim, K.-S.; Huang, F.; Wong, B. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)

    2005-07-01

    FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. FEAST models the thermo-elastic, thermo-elasto-plastic and creep deformations in CANDU fuel. FEAT (Finite Element Analysis for Temperature) is another AECL computer code and is used to assess the thermal integrity of fuel elements. FEAT models the steady-state and transient heat flows in CANDU fuel, under conditions such as flux depression, end flux peaking, temperature-dependent thermal conductivity, and non-uniform time-dependent boundary conditions. Both computer programs are used in design and qualification analyses of CANDU fuel. Formal qualifications (including coding verification and validation) of both codes were performed, in accordance with AECL software quality assurance (SQA) manual and procedures that are consistent with CSA N286.7-99. Validation of FEAST 3.0 shows very good agreement with independent analytical solutions or measurements. Validation of FEAT 4.0 also shows very good agreement with independent WIMS-AECL calculations, analytical solutions, ANSYS calculations and measurement. (author)

  9. Studies on groundwater flow and radionuclide migration at underground environments. Final report of collaboration research between JAERI and AECL

    International Nuclear Information System (INIS)

    Ogawa, Hiromichi; Nagao, Seiya; Yamaguchi, Tetsuji

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) conducted a collaboration program Phase II with the Atomic Energy of Canada Limited (AECL) from 1994 to 1998. The program was started to contribute the establishment of safety assessment methodology for the geological disposal of high-level radioactive wastes on the basis of the results from the Phase I program (1987-1993). The Phase II program consisted of following experimental items: (1) radionuclide migration experiments for quarried blocks (1m x 1m x 1m) of granite with natural fracture under in-situ geochemical conditions at 240 m level of Underground Research Laboratory of AECL; (2) study on the effects of dissolved organic materials extracted from natural groundwaters on radionuclide migration; (3) study on groundwater flow using environmental isotopes at two different geologic environments; (4) development of groundwater flow and radionuclide transport model for heterogeneous geological media. The mobility of radionuclides was retarded in the fracture by the deep geological conditions and the fracture paths. The groundwater humic substances with high molecular size were enhanced for the mobility of radionuclides in the sand and granitic media due to the complexation. The application of 36 Cl and 129 I for the analysis on the long-term groundwater flow can be validated on the basis of investigation at the URL site. Moreover, the geostatistical model for the analysis on groundwater flow and radionuclide migration was developed, and was able to describe the groundwater flow and the migration of environmental tracers at AECL sites. This report summaries the results of the Phase II program between JAERI and AECL. (author)

  10. Studies on groundwater flow and radionuclide migration at underground environments. Final report of collaboration research between JAERI and AECL

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Hiromichi; Nagao, Seiya; Yamaguchi, Tetsuji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) conducted a collaboration program Phase II with the Atomic Energy of Canada Limited (AECL) from 1994 to 1998. The program was started to contribute the establishment of safety assessment methodology for the geological disposal of high-level radioactive wastes on the basis of the results from the Phase I program (1987-1993). The Phase II program consisted of following experimental items: (1) radionuclide migration experiments for quarried blocks (1m x 1m x 1m) of granite with natural fracture under in-situ geochemical conditions at 240 m level of Underground Research Laboratory of AECL; (2) study on the effects of dissolved organic materials extracted from natural groundwaters on radionuclide migration; (3) study on groundwater flow using environmental isotopes at two different geologic environments; (4) development of groundwater flow and radionuclide transport model for heterogeneous geological media. The mobility of radionuclides was retarded in the fracture by the deep geological conditions and the fracture paths. The groundwater humic substances with high molecular size were enhanced for the mobility of radionuclides in the sand and granitic media due to the complexation. The application of {sup 36}Cl and {sup 129}I for the analysis on the long-term groundwater flow can be validated on the basis of investigation at the URL site. Moreover, the geostatistical model for the analysis on groundwater flow and radionuclide migration was developed, and was able to describe the groundwater flow and the migration of environmental tracers at AECL sites. This report summaries the results of the Phase II program between JAERI and AECL. (author)

  11. AECL'S approach to managing long term liabilities at Chalk River Laboratories. Annex II

    International Nuclear Information System (INIS)

    Audet, M.C.

    2006-01-01

    Chalk River Laboratories (CRL) is a large nuclear research and development/ industrial site operated by Atomic Energy of Canada Limited (AECL). Construction of the site started in 1944, and it now includes over 100 buildings/facilities operating in various nuclear fields. A well developed decommissioning programme exists at CRL, with progress being made on decommissioning older redundant buildings, in parallel with ongoing site operations and development. The decommissioning programme is predicated on the assumption that the current nuclear operations will continue over a 100 year operating period, but with a decline towards the end of the period. Although decommissioning and remediation work will be carried out throughout the operational period, residual levels of activity remaining in a few areas will require institutional control (IC) for an assumed period of 300 years. The intention is to complete all necessary active remediation work before the start of the IC period and thereafter rely only on passive means to reduce residual contamination to levels that do not require IC measures. The latter include environmental monitoring, active and passive controls to prevent intrusion, and management controls to prohibit access or development. A formal information and records management programme at CRL has been initiated. (author)

  12. Retrofit of AECL CAN6 seals into the Pickering shutdown cooling pumps

    International Nuclear Information System (INIS)

    Rhodes, D.; Metcalfe, R.; Brown, G.

    1997-01-01

    The existing mechanical seals in the shutdown cooling (SDC) pumps at the eight-unit Pickering Nuclear Generating Station have caused as least seven forced outages in the last fifteen years. The SDC pumps were originally intended to run only during shutdowns, mostly at low pressure, except for short periods during routine testing of SDC isolation valves while the plant is operating at full pressure to verify that the emergency core injection system is available. Unfortunately, in practice, some SDC pumps must be run much more frequently than this to prevent overheating or freezing of components in the system while the plant is at power. This more severe service has decreased seal lifetime from about 8000 running hours to about 3000 running hours. Rather than tackling the difficult task of eliminating on-power running of the pumps, Pickering decided to install a more robust seal design that could withstand this. Through the process of competitive tender, AECL's CAN6 seal was chosen. This seal has a successful history in similarly demanding conditions in boiling water reactors in the USA. To supplement this and demonstrate there would be no 'surprises,' a 2000-hour test program was conducted. Testing consisted of simulating all the expected conditions, plus some special tests under abnormal conditions. This has given assurance that the seal will operate reliably in the Pickering shutdown cooling pumps. (author)

  13. The contribution of AECL CommercialProducts to nuclear medicine and radiation processing

    International Nuclear Information System (INIS)

    Beddoes, J.M.

    1980-02-01

    A review is given of the technology of the uses of radiation equipment and radioisotopes, in which field Canada has long been a world leader. AECL CommercialProducts has pioneered many of the most important applications. The development and sale of Co-60 radiation teletherapy units for cancer treatment is a familiar example of such an application, and CommercialProducts dominates the world market. Another such example is the marketing of Mo-99, which is produced in the reactors at Chalk River, and from which the short-lived daughter Tc-99 is eluted as required for use in in-vivo diagnosis. New products coming into use for this purpose include Tl-201, I-123, Ga-67 and In-111, all produced in the TRIUMF cyclotron in Vancouver, while I-125 continues to be in demand for in-vitro radioimmunoassays. Radioisotopes continue to play an important part in manufacturing, where their well-known uses include controlling thickness, contents, etc., in production, and industrial radiography. The application of large industrial irradiators for the sterilization of medical products is now a major world industry for which Commercial Products is the main manufacturer. Isotopes are also used in products such as smoke detectors. Isotopes continue to find extensive use as tracers, both in industrial applications and in animal and plant biology studies. Some more recent uses include pest control by the 'sterile male' technique and neutron activation and delayed neutron counting in uranium assay. (auth)

  14. Retrofit of AECL CAN6 seals into the Pickering shutdown cooling pumps

    International Nuclear Information System (INIS)

    Rhodes, D.; Metcalfe, R.; Brown, G.; Kiameh, P.; Burchett, P.

    1997-01-01

    The existing mechanical seals in the shutdown cooling (SDC) pumps at the eight-unit Pickering Nuclear Generating Station have caused at least seven forced outages in the last fifteen years. The SDC pumps were originally intended to run only during shutdowns, mostly at low pressure, except for short periods during routine testing of SDC isolation valves while the plant is operating at full pressure to verify that the emergency core injection system is available. Unfortunately, in practice, some SDC pumps must be run much more frequently than this to prevent overheating or freezing of components in the system while the plant is at power. This more severe service has decreased seal lifetime from about 8000 running hours to about 3000 running hours. Rather than tackling the difficult task of eliminating on-power running of the pumps, Pickering decided to install a more robust seal design that could withstand this. Through the process of competitive tender, AECL's CAN6 seal was chosen. This seal has a successful history in similarly demanding conditions in boiling water reactors in the USA. To supplement this and demonstrate there would be no 'surprises,' a 2000-hour test program was conducted. Testing consisted of simulating all the expected conditions, plus some special tests under abnormal conditions. This has given assurance that the seal will operate reliably in the Pickering shutdown cooling pumps. (author)

  15. Experience with remediating radiostrontium-contaminated ground water and surface water with versions of AECL's CHEMIC process

    International Nuclear Information System (INIS)

    Vijayan, S.

    2006-01-01

    Numerous approaches have been developed for the remediation of radiostrontium ( 90 Sr) contaminated ground water and surface water. Several strontium-removal technologies have been assessed and applied at AECL's (Atomic Energy of Canada Limited) Chalk River Laboratories. These include simple ion exchange (based on non-selective natural zeolites or selective synthetic inorganic media), and precipitation and filtration with or without ion exchange as a final polishing step. AECL's CHEMIC process is based on precipitation-microfiltration and ion-exchange steps. This paper presents data related to radiostrontium removal performance and other operational experiences including troubleshooting with two round-the-clock, pilot-scale water remediation plants based on AECL's CHEMIC process at the Chalk River Laboratories site. These plants began operation in the early 1990s. Through optimization of process chemistry and operation, high values for system capability and system availability factors, and low concentrations of 90 Sr in the discharge water approaching drinking water standard can be achieved. (author)

  16. Thermal-hydraulic interfacing code modules for CANDU reactors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.S.; Gold, M.; Sills, H. [Ontario Hydro Nuclear, Toronto (Canada)] [and others

    1997-07-01

    The approach for CANDU reactor safety analysis in Ontario Hydro Nuclear (OHN) and Atomic Energy of Canada Limited (AECL) is presented. Reflecting the unique characteristics of CANDU reactors, the procedure of coupling the thermal-hydraulics, reactor physics and fuel channel/element codes in the safety analysis is described. The experience generated in the Canadian nuclear industry may be useful to other types of reactors in the areas of reactor safety analysis.

  17. Thermal-hydraulic interfacing code modules for CANDU reactors

    International Nuclear Information System (INIS)

    Liu, W.S.; Gold, M.; Sills, H.

    1997-01-01

    The approach for CANDU reactor safety analysis in Ontario Hydro Nuclear (OHN) and Atomic Energy of Canada Limited (AECL) is presented. Reflecting the unique characteristics of CANDU reactors, the procedure of coupling the thermal-hydraulics, reactor physics and fuel channel/element codes in the safety analysis is described. The experience generated in the Canadian nuclear industry may be useful to other types of reactors in the areas of reactor safety analysis

  18. Current status of the waste identification program at AECL's Chalk River Laboratories

    International Nuclear Information System (INIS)

    Csullog, G.W.; Edwards, N.W.; TerHuurne, M.A.

    1998-01-01

    The management of routine operating waste by Waste Management and Decommissioning (WM and D) at Atomic Energy of Canada Limited's (AECL) Chalk River Laboratories (CRL) is supported by the Waste Identification (WI) Program. The principal purpose of the WI Program is to minimize the cost and the effort associated with waste characterization and waste tracking, which are needed to optimize waste handling, storage and disposal. The major steps in the WI Program are: (1) identify and characterize the processes that generate the routine radioactive wastes accepted by WM and D - radioisotope production, radioisotope use, reactor operation, fuel fabrication, et cetera (2) identify and characterize the routine blocks of waste generated by each process or activity - the initial characterization is based on inference (process knowledge) (3) prepare customized, template data sheets for each routine waste block - templates contain information such as package type, waste material, waste type, solidifying agent, the average non-radiological contaminant inventory, the average radiological contaminant inventory, and the waste class (4) ensure generators 'use the right piece of paper with the right waste' when they transfer waste to WM and D - that is they use the correct template data sheets to transfer routine wastes, by: identifying and marking waste collection points in the generator's facility; ensuring that generators implement effective waste collection/segregation procedures; implementing standard procedures to transfer waste to WM and D; and, auditing waste collection and segregation within a generator's facility (5) determine any additional waste block characterization requirements (is anything needed beyond the original characterization by process knowledge?) This paper describes the WI Program, it provides an example of its implementation, and it summarizes the current status of its implementation for both CRL and non-CRL waste generators. (author)

  19. AECL'S (Atomic Energy Canada Limited) R and D program in health and environmental sciences

    International Nuclear Information System (INIS)

    Osborne, R.V.

    1996-01-01

    Radiological protection is a fundamental requirement in any nuclear technology endeavour. It is also an area where public concerns are often expressed. If protection is inadequate, or is believed to be so, or if concerns are not addressed, the beneficial application of nuclear technologies is inhibited. Historically. AECL, as the driver of nuclear technology in Canada, has ensured that the growing Canadian nuclear industry and other users of the technology have a sound technical base to support, explain and confirm all aspects of radiological protection. Meeting this need has meant developing and maintaining R%D programs in environmental sciences, health physics, radiation biology, and radiological health matters in general. The programs undertaken encompass the links from sources of radiation exposure and radionuclides to potential impact on biota and on human health. The behaviours of radionuclides released to the atmosphere, surface waters, or ground waters are examined and described quantitatively to enable predictions to be made of the radiation doses received in different parts of the biosphere and by people. Radiation properties and human physiological and biokinetic processes are studied to provide quantitative links from exposure to radiation dose in tissues and organs. Biological processes involved in determining whether there are any consequences to health from small absorbed doses are identified at levels ranging from molecular level, to cells in tissue culture, and animals. Throughout the programs, required measurement technologies are developed. The results of the R%D have contributed to radiological protection programs being soundly based and, equally important, are being seen to be soundly based. (author)

  20. AECL strategy for surface-based investigations of potential disposal sites and the development of a geosphere model for a site

    International Nuclear Information System (INIS)

    Whitaker, S.H.; Brown, A.; Davison, C.C.; Gascoyne, M.; Lodha, G.S.; Stevenson, D.R.; Thorne, G.A.; Tomsons, D.

    1994-05-01

    The objective of this report is to summarize AECL's strategy for surface-based geotechnical site investigations used in screening and evaluating candidate areas and candidate sites for a nuclear fuel waste repository and for the development of geosphere models of sites. The report is one of several prepared by national nuclear fuel waste management programs for the Swedish Nuclear Fuel and Waste Management Co. (SKB) to provide international background on site investigations for SKB's R and D programme on siting.The scope of the report is limited to surface-based investigations of the geosphere, those done at surface or in boreholes drilled from surface. The report discusses AECL's investigation strategy and the methods proposed for use in surface-based reconnaissance and detailed site investigations at potential repository sites. Site investigations done for AECL's Underground Research Laboratory are used to illustrate the approach. The report also discusses AECL's strategy for developing conceptual and mathematical models of geological conditions at sites and the use of these models in developing a model (Geosphere Model) for use in assessing the performance of the disposal system after a repository is closed. Models based on the site data obtained at the URL are used to illustrate the approach. Finally, the report summarizes the lessons learned from AECL's R and D program on site investigations and mentions some recent developments in the R and D program. 120 refs, 33 figs, 7 tabs

  1. Antibiotics from bacillus subtilis AECL69 8. isolation and purification of a complex of antibacterial antibiotics x

    International Nuclear Information System (INIS)

    Ahmad, M.S.; Malik, M.A.; Shaukat, G.A.

    1996-01-01

    A bacterial strain bacillus subtilis AECL69 produces two anti bacterial antibiotics in a specified complex or synthetic medium. One of the antibiotics is characteristically active against Xanthomonas citri. Procedures have been described to isolate and purify a complex of xanthmonas antibiotics from the fermented complex broths, and from the fermented synthetic medium as well. Paper chromatography coupled with bioautography has shown that the complex of xanthomonas antibiotics has at least three components. The three components were indicated irrespective of the fact whether it was isolated from the fermented complex or synthetic broth. (author)

  2. Verification of the thermal module in the ELESIM code and the associated uncertainty analysis

    International Nuclear Information System (INIS)

    Arimescu, V.I.; Williams, A.F.; Klein, M.E.; Richmond, W.R.; Couture, M.

    1997-01-01

    Temperature is a critical parameter in fuel modelling because most of the physical processes that occur in fuel elements during irradiation are thermally activated. The focus of this paper is the temperature distribution calculation used in the computer code ELESIM, developed at AECL to model the steady state behaviour of CANDU fuel. A validation procedure for fuel codes is described and applied to ELESIM's thermal calculation

  3. Analysis of the results for the AECL cohort in the IARC study on the radiogenic cancer risk among nuclear industry workers in fifteen countries

    International Nuclear Information System (INIS)

    Ashmore, J.P.; Gentner, N.E.; Osborne, R.V.

    2007-01-01

    Over the last two decades there have been attempts to estimate the risks from occupational exposure in the nuclear industry by epidemiological assessments on cohorts of workers. However, generally low doses and relatively small worker populations have limited the precision of such studies. In 1995 the International Agency for Research on Cancer (IARC) completed a study that involved workers from facilities in the USA, UK and AECL. In 2005, IARC completed a further study involving nuclear workers from 15 countries including Canada. Surprisingly, the risk ascribed to the Canadian cohort for all cancers excluding leukaemia, driven by the AECL component, was significantly higher than the cohort as a whole. The work described in this report is an attempt to unravel what might have accounted for the divergence between the results for the AECL cohort and the others

  4. Analysis of the results for the AECL cohort in the IARC study on the radiogenic cancer risk among nuclear industry workers in fifteen countries

    Energy Technology Data Exchange (ETDEWEB)

    Ashmore, J.P. [Ponsonby and Associates, Manotick, Ontario (Canada); Gentner, N.E. [Consultant, Petawawa, Ontario (Canada); Osborne, R.V. [Ranasara Consultants Inc., Deep River, Ontario (Canada)

    2007-03-31

    Over the last two decades there have been attempts to estimate the risks from occupational exposure in the nuclear industry by epidemiological assessments on cohorts of workers. However, generally low doses and relatively small worker populations have limited the precision of such studies. In 1995 the International Agency for Research on Cancer (IARC) completed a study that involved workers from facilities in the USA, UK and AECL. In 2005, IARC completed a further study involving nuclear workers from 15 countries including Canada. Surprisingly, the risk ascribed to the Canadian cohort for all cancers excluding leukaemia, driven by the AECL component, was significantly higher than the cohort as a whole. The work described in this report is an attempt to unravel what might have accounted for the divergence between the results for the AECL cohort and the others.

  5. Validation of the ORIGEN-S code for predicting radionuclide inventories in used CANDU Fuel

    International Nuclear Information System (INIS)

    Tait, J.C.; Gauld, I.; Kerr, A.H.

    1994-10-01

    The safety assessment being conducted by AECL Research for the concept of deep geological disposal of used CANDU UO 2 fuel requires the calculation of radionuclide inventories in the fuel to provide source terms for radionuclide release. This report discusses the validation of selected actinide and fission-product inventories calculated using the ORIGEN-S code coupled with the WIMS-AECL lattice code, using data from analytical measurements of radioisotope inventories in Pickering CANDU reactor fuel. The recent processing of new ENDF/B-VI cross-section data has allowed the ORIGEN-S calculations to be performed using the most up-to-date nuclear data available. The results indicate that the code is reliably predicting actinide and the majority of fission-product inventories to within the analytical uncertainty. 38 refs., 4 figs., 5 tabs

  6. Validation of the ORIGEN-S code for predicting radionuclide inventories in used CANDU fuel

    International Nuclear Information System (INIS)

    Tait, J.C.; Gauld, I.; Kerr, A.H.

    1995-01-01

    The safety assessment being conducted by AECL Research for the concept of deep geological disposal of used CANDU UO 2 fuel requires the calculation of radionuclide inventories in the fuel to provide source terms for radionuclide release. This report discusses the validation of selected actinide and fission-product inventories calculated using the ORIGEN-S code coupled with the WIMS-AECL lattice code, using data from analytical measurements of radioisotope inventories in Pickering CANDU reactor fuel. The recent processing of new ENDF/B-VI cross-section data has allowed the ORIGEN-S calculations to be performed using the most up-to-date nuclear data available. The results indicate that the code is reliably predicting actinide and the majority of fission-product inventories to within the analytical uncertainty. ((orig.))

  7. Research on radionuclide migration under subsurface geochemical conditions. JAERI/AECL Phase II Collaborative Program Year 1 (joint research)

    International Nuclear Information System (INIS)

    1998-11-01

    A radionuclide migration experiment program for fractured rocks was performed under the JAERI/AECL Phase-II Collaborative Program on research and development in radioactive waste management. The program started in the fiscal year 1993, as a five-year program consists of Quarried block radionuclide migration program, Speciation of long-lived radionuclides in groundwater, Isotopic hydrogeology and Groundwater flow model development. During the first year of the program (Program Year 1: March 18, 1994 - September 30, 1994), a plan was developed to take out granite blocks containing part of natural water-bearing fracture from the wall of the experimental gallery at the depth of 240 m, and literature reviews were done in the area of the speciation of long-lived radionuclides in groundwater, isotopic hydrogeology and the groundwater flow model development to proceed further work for the Program Year 2. (author)

  8. Validation of computer codes used in the safety analysis of Canadian research reactors

    International Nuclear Information System (INIS)

    Bishop, W.E.; Lee, A.G.

    1998-01-01

    AECL has embarked on a validation program for the suite of computer codes that it uses in performing the safety analyses for its research reactors. Current focus is on codes used for the analysis of the two MAPLE reactors under construction at Chalk River but the program will be extended to include additional codes that will be used for the Irradiation Research Facility. The program structure is similar to that used for the validation of codes used in the safety analyses for CANDU power reactors. (author)

  9. Burnup calculation of a CANDU6 reactor using the Serpent and MCNP6 codes

    Energy Technology Data Exchange (ETDEWEB)

    Hussein, M.S.; Bonin, H.W., E-mail: mohamed.hussein@rmc.ca, E-mail: bonin-h@rmc.ca [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, ON (Canada); Lewis, B.J., E-mail: Brent.Lewis@uoit.ca [Univ. of Ontario Inst. of Tech., Faculty of Energy Systems and Nuclear Science, Oshawa, ON (Canada)

    2014-07-01

    A study of fuel burnup for the CANDU6 reactor is carried out to validate the most recent versions of the probabilistic transport code (MCNP6) and the continuous energy burnup calculation code (Serpent). These two codes allow for 3-D geometry calculation accounting for a detailed analysis without unit-cell homogenization. On the other hand, the WIMS-AECL computer program is used to model neutron transport in nuclear-reactor lattices for design, safety analysis, and operation. It works with two-dimensional regions and can perform collision probability calculations for a periodic structure of the lattice cell. In the present work, the multiplication factor, the total flux and fuel burnup could be calculated for a CANDU6 nuclear reactor based on the GENTILLY-2 core design. The MCNP6 and Serpent codes provide a calculation of the track length estimated flux per neutron source. This estimated flux is then scaled with normalization to the reactor power in order to provide a flux in unit of n/cm{sup 2}s. Good agreement is observed between the actual total flux calculated by MCNP6, Serpent and WIMS-AECL. The effective multiplication factors of the whole core CANDU6 reactor are further calculated as a function of burnup and further compared to those calculated by WIMS-AECL where excellent agreement is also obtained. (author)

  10. Burnup calculation of a CANDU6 reactor using the Serpent and MCNP6 codes

    International Nuclear Information System (INIS)

    Hussein, M.S.; Bonin, H.W.; Lewis, B.J.

    2014-01-01

    A study of fuel burnup for the CANDU6 reactor is carried out to validate the most recent versions of the probabilistic transport code (MCNP6) and the continuous energy burnup calculation code (Serpent). These two codes allow for 3-D geometry calculation accounting for a detailed analysis without unit-cell homogenization. On the other hand, the WIMS-AECL computer program is used to model neutron transport in nuclear-reactor lattices for design, safety analysis, and operation. It works with two-dimensional regions and can perform collision probability calculations for a periodic structure of the lattice cell. In the present work, the multiplication factor, the total flux and fuel burnup could be calculated for a CANDU6 nuclear reactor based on the GENTILLY-2 core design. The MCNP6 and Serpent codes provide a calculation of the track length estimated flux per neutron source. This estimated flux is then scaled with normalization to the reactor power in order to provide a flux in unit of n/cm 2 s. Good agreement is observed between the actual total flux calculated by MCNP6, Serpent and WIMS-AECL. The effective multiplication factors of the whole core CANDU6 reactor are further calculated as a function of burnup and further compared to those calculated by WIMS-AECL where excellent agreement is also obtained. (author)

  11. Validation of the COBRA code for dry out power calculation in CANDU type advanced fuels

    International Nuclear Information System (INIS)

    Daverio, Hernando J.

    2003-01-01

    Stern Laboratories perform a full scale CHF testing of the CANFLEX bundle under AECL request. This experiment is modeled with the COBRA IV HW code to verify it's capacity for the dry out power calculation . Good results were obtained: errors below 10 % with respect to all data measured and 1 % for standard operating conditions in CANDU reactors range . This calculations were repeated for the CNEA advanced fuel CARA obtaining the same performance as the CANFLEX fuel. (author)

  12. Validation of physics and thermalhydraulic computer codes for advanced Candu reactor applications

    International Nuclear Information System (INIS)

    Wren, D.J.; Popov, N.; Snell, V.G.

    2004-01-01

    Atomic Energy of Canada Ltd. (AECL) is developing an Advanced Candu Reactor (ACR) that is an evolutionary advancement of the currently operating Candu 6 reactors. The ACR is being designed to produce electrical power for a capital cost and at a unit-energy cost significantly less than that of the current reactor designs. The ACR retains the modular Candu concept of horizontal fuel channels surrounded by a heavy water moderator. However, ACR uses slightly enriched uranium fuel compared to the natural uranium used in Candu 6. This achieves the twin goals of improved economics (via large reductions in the heavy water moderator volume and replacement of the heavy water coolant with light water coolant) and improved safety. AECL has developed and implemented a software quality assurance program to ensure that its analytical, scientific and design computer codes meet the required standards for software used in safety analyses. Since the basic design of the ACR is equivalent to that of the Candu 6, most of the key phenomena associated with the safety analyses of ACR are common, and the Candu industry standard tool-set of safety analysis codes can be applied to the analysis of the ACR. A systematic assessment of computer code applicability addressing the unique features of the ACR design was performed covering the important aspects of the computer code structure, models, constitutive correlations, and validation database. Arising from this assessment, limited additional requirements for code modifications and extensions to the validation databases have been identified. This paper provides an outline of the AECL software quality assurance program process for the validation of computer codes used to perform physics and thermal-hydraulics safety analyses of the ACR. It describes the additional validation work that has been identified for these codes and the planned, and ongoing, experimental programs to extend the code validation as required to address specific ACR design

  13. Validation of Non-Invasive Waste Assay System (Gamma Box Counter) Performance at AECL Whiteshell Laboratories - 13136

    International Nuclear Information System (INIS)

    Attas, E.M.; Bialas, E.; Rhodes, M.J.

    2013-01-01

    Low-level radioactive waste (LLW) in solid form, resulting from decommissioning and operations activities at AECL's Whiteshell Laboratories (WL), is packaged in B-25 and B-1000 standard waste containers and characterized before it is shipped to an on-site interim storage facility, pending AECL decisions on long term management of its LLW. Assay of the waste packages before shipment contributes to an inventory of the interim storage facility and provides data to support acceptance at a future repository. A key characterization step is a gamma spectrometric measurement carried out under standard conditions using an automated, multi-detector Waste Assay System (WAS), purchased from Antech Corporation. A combination of ORTEC gamma acquisition software and custom software is used in this system to incorporate multiple measurements from two collimated high-resolution detectors. The software corrects the intensities of the gamma spectral lines for geometry and attenuation, and generates a table of calculated activities or limits of detection for a user-defined list of radioisotopes that may potentially be present. Validation of WAS performance was a prerequisite to routine operation. Documentation of the validation process provides assurance of the quality of the results produced, which may be needed one or two decades after they were generated. Aspects of the validation included setting up a quality control routine, measurements of standard point sources in reproducible positions, study of the gamma background, optimization of user-selectable software parameters, investigation of the effect of non-uniform distribution of materials and radionuclides, and comparison of results with measurements made using other gamma detector systems designed to assay bulk materials. The following key components of the validation process have been established. A daily quality control routine has been instituted, to verify stability of the gamma detector operation and the background levels

  14. Variations in the response of AECL random coil seals as a function of the angular position of the probe

    International Nuclear Information System (INIS)

    Silk, M.G.

    1986-04-01

    The AECL random coil seal is to be used as a Nuclear Safeguards seal to deter and detect tampering with nuclear material in store. To be effective the ultrasonic signature from the seal must remain constant and be different from that of other seals. Angular variations in the ultrasonic response from certain seals have, however, been observed and the programme of study reported here has been carried out in order to clarify the source of this variation. It is shown that the variation observed may most probably be attributed to the ultrasonic probes used in the investigation and, in particular, to deviation of the probe beam from circularity. However it is probable that the angle of the beam with respect to the probe case (squint) is also a contributory factor. In addition, to reduce the degree of angular variation it is important to exclude air bubbles and to ensure that the coil is placed as centrally in the beam as possible. It is anticipated that the exclusion of air bubbles will be easier in the field than in the laboratory studies. The need to place the seal reasonably centrally with respect to the beam places some minor limits on the coil design and also makes it essential that the probe fits closely into its holder in the seal as any slackness may give rise to signature variations. (author)

  15. Computer code qualification program for the Advanced CANDU Reactor

    International Nuclear Information System (INIS)

    Popov, N.K.; Wren, D.J.; Snell, V.G.; White, A.J.; Boczar, P.G.

    2003-01-01

    Atomic Energy of Canada Ltd (AECL) has developed and implemented a Software Quality Assurance program (SQA) to ensure that its analytical, scientific and design computer codes meet the required standards for software used in safety analyses. This paper provides an overview of the computer programs used in Advanced CANDU Reactor (ACR) safety analysis, and assessment of their applicability in the safety analyses of the ACR design. An outline of the incremental validation program, and an overview of the experimental program in support of the code validation are also presented. An outline of the SQA program used to qualify these computer codes is also briefly presented. To provide context to the differences in the SQA with respect to current CANDUs, the paper also provides an overview of the ACR design features that have an impact on the computer code qualification. (author)

  16. Code Cactus; Code Cactus

    Energy Technology Data Exchange (ETDEWEB)

    Fajeau, M; Nguyen, L T; Saunier, J [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-09-01

    This code handles the following problems: -1) Analysis of thermal experiments on a water loop at high or low pressure; steady state or transient behavior; -2) Analysis of thermal and hydrodynamic behavior of water-cooled and moderated reactors, at either high or low pressure, with boiling permitted; fuel elements are assumed to be flat plates: - Flowrate in parallel channels coupled or not by conduction across plates, with conditions of pressure drops or flowrate, variable or not with respect to time is given; the power can be coupled to reactor kinetics calculation or supplied by the code user. The code, containing a schematic representation of safety rod behavior, is a one dimensional, multi-channel code, and has as its complement (FLID), a one-channel, two-dimensional code. (authors) [French] Ce code permet de traiter les problemes ci-dessous: 1. Depouillement d'essais thermiques sur boucle a eau, haute ou basse pression, en regime permanent ou transitoire; 2. Etudes thermiques et hydrauliques de reacteurs a eau, a plaques, a haute ou basse pression, ebullition permise: - repartition entre canaux paralleles, couples on non par conduction a travers plaques, pour des conditions de debit ou de pertes de charge imposees, variables ou non dans le temps; - la puissance peut etre couplee a la neutronique et une representation schematique des actions de securite est prevue. Ce code (Cactus) a une dimension d'espace et plusieurs canaux, a pour complement Flid qui traite l'etude d'un seul canal a deux dimensions. (auteurs)

  17. Assessment of CANDU physics codes using experimental data - II: CANDU core physics measurements

    International Nuclear Information System (INIS)

    Roh, Gyu Hong; Jeong, Chang Joon; Choi, Hang Bok

    2001-11-01

    Benchmark calculations of the advanced CANDU reactor analysis tools (WIMS-AECL, SHETAN and RFSP) and the Monte Carlo code MCNP-4B have been performed using Wolsong Units 2 and 3 Phase-B measurement data. In this study, the benchmark calculations have been done for the criticality, boron worth, reactivity device worth, reactivity coefficient, and flux scan. For the validation of the WIMS-AECL/SHETANRFSP code system, the lattice parameters of the fuel channel were generated by the WIMS-AECL code, and incremental cross sections of reactivity devices and structural material were generated by the SHETAN code. The results have shown that the criticality is under-predicted by -4 mk. The reactivity device worths are generally consistent with the measured data except for the strong absorbers such as shutoff rod and mechanical control absorber. The heat transport system temperature coefficient and flux distributions are in good agreement with the measured data. However, the moderator temperature coefficient has shown a relatively large error, which could be caused by the incremental cross-section generation methodology for the reactivity device. For the MCNP-4B benchmark calculation, cross section libraries were newly generated from ENDF/B-VI release 3 through the NJOY97.114 data processing system and a three-dimensional full core model was developed. The simulation results have shown that the criticality is estimated within 4 mk and the estimated reactivity worth of the control devices are generally consistent with the measurement data, which implies that the MCNP code is valid for CANDU core analysis. In the future, therefore, the MCNP code could be used as a reference tool to benchmark design and analysis codes for the advanced fuels for which experimental data are not available

  18. Verification of the thermal module in the ELESIM code and the associated uncertainty analysis

    International Nuclear Information System (INIS)

    Arimescu, V.I.; Williams, A.F.; Klein, M.E.; Richmond, W.R.; Couture, M.

    1997-09-01

    Temperature is a critical parameter in fuel modelling because most of the physical processes that occur in fuel elements during irradiation are thermally activated. The focus of this paper is the temperature distribution calculation used in the computer code ELESIM, developed at AECL to model the steady-state behaviour of CANDU fuel. A validation procedure for fuel codes is described and applied to ELESIM's thermal calculation.The effects of uncertainties in model parameters, like Uranium Dioxide thermal conductivity, and input variables, such as fuel element linear power, are accounted for through an uncertainty analysis using Response Surface and Monte Carlo techniques

  19. Modeling approach for annular-fuel elements using the ASSERT-PV subchannel code

    International Nuclear Information System (INIS)

    Dominguez, A.N.; Rao, Y.

    2012-01-01

    The internally and externally cooled annular fuel (hereafter called annular fuel) is under consideration for a new high burn-up fuel bundle design in Atomic Energy of Canada Limited (AECL) for its current, and its Generation IV reactor. An assessment of different options to model a bundle fuelled with annular fuel elements is presented. Two options are discussed: 1) Modify the subchannel code ASSERT-PV to handle multiple types of elements in the same bundle, and 2) coupling ASSERT-PV with an external application. Based on this assessment, the selected option is to couple ASSERT-PV with the thermalhydraulic system code CATHENA. (author)

  20. Results of a survey on accident and safety analysis codes, benchmarks, verification and validation methods

    International Nuclear Information System (INIS)

    Lee, A.G.; Wilkin, G.B.

    1995-01-01

    This report is a compilation of the information submitted by AECL, CIAE, JAERI, ORNL and Siemens in response to a need identified at the 'Workshop on R and D Needs' at the IGORR-3 meeting. The survey compiled information on the national standards applied to the Safety Quality Assurance (SQA) programs undertaken by the participants. Information was assembled for the computer codes and nuclear data libraries used in accident and safety analyses for research reactors and the methods used to verify and validate the codes and libraries. Although the survey was not comprehensive, it provides a basis for exchanging information of common interest to the research reactor community

  1. Comparison of MCNP and WIMS-AECL/RFSP calculations with high temperature substitution experiments in ZED-2 using CANFLEX-L VRF

    International Nuclear Information System (INIS)

    Pencer, J.; Bromley, B.P.; Watts, D.G.; Carlson, P.; Rauket, A.; Zeller, M.

    2009-01-01

    This paper summarizes comparisons of calculation results from MCNP5 and WIMS-AECL / RFSP with experimental results obtained from the Zero Energy Deuterium (ZED-2) critical facility, examining CANFLEX Low Void Reactivity Fuel (CANFLEX-LVRF) in heated channels, substituted into a reference lattice and cooled under ACR-like coolant conditions, with H 2 O, air, or CO 2 as an air substitute. CANFLEX-LVRF shares features in common with the ACR-1000 fuel, notably an increase in enrichment (over natural uranium) in the outer elements of the fuel bundle, and presence of a neutron absorber in the central element. The reference and substituted fuel channels were arranged in a 24.5-cm hexagonal lattice in order to provide neutron similarity to the 24-cm square lattice pitch of the ACR-1000. These results therefore provide useful data for validation of the reactor physics toolset for use in ACR-1000 applications. For the mixed lattices, results for both MCNP5 and WIMS-AECL / RFSP show small biases in k eff , ranging from -7 mk to -5 mk, small biases in coolant void reactivity, ranging from -1 mk to +0.5 mk, and good agreement for copper activation rate distributions (based on calculated neutron flux). Bare core MCNP and WIMS-AECL stand-alone results, based on substitution analysis, also show small biases in k eff , ranging from -6 mk to -0.4 mk, and small biases in coolant void reactivity, ranging from -0.3 mk to +3.7 mk. This validation exercise thus gives good agreement between measurement and calculation and provides confidence in the accuracy of the physics toolset. (author)

  2. Rock fracture dynamics research at AECL's Underground Research Laboratory: applications to geological disposal of radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    Young, R.P. [Univ. of Toronto, Toronto, ON (Canada); Haycox, J.R. [Applied Seismology Consultants Limited, Shrewsbury, Shropshire (United Kingdom); Martino, J. [Atomic Energy of Canada Limited, Pinawa, MB (Canada)

    2011-07-01

    Studies of rock fracture dynamics at AECL's Underground Research Laboratory (URL) have helped to provide a fundamental understanding of how crystalline rock responds to stresses induced from excavation, pressurization and temperature changes. The data acquired continue to provide insights into how a facility for the future geological disposal of radioactive waste could be engineered. Research into microseismic (MS), acoustic emission (AE), and ultrasonic velocity measurements has been performed on the full-scale sealed, pressurized, and heated horizontal elliptical tunnel at the Tunnel Sealing Experiment (TSX). The continuous monitoring of the experiment for 8 years provides a unique dataset for the understanding of the medium-term performance of an engineered disposal facility. This paper summarizes the results, interpretations and key findings of the experiment paying particular focus to the heating and cooling/depressurization of the chamber. Initial drilling of the tunnel and bulkheads causes microfracturing around the tunnel, mapped by MS and AEs, and is used as a benchmark for fracturing representing the excavated damaged zone (EDZ). There is no further extension to the volume during pressurization or heating of the tunnel suggesting an increase in crack density and coalescence of cracks rather than extension into unfractured rock. The dominant structure within the seismic cloud has been investigated using a statistical approach applying the three-point method. MS events in the roof exhibit a dominant pattern of sub-horizontal and shallow-dipping well defined planar features, but during cooling and depressurization a 45 degree dip normal to the tunnel axis is observed, which may be caused by movement in the rock-concrete interface due to differential cooling of the bulkhead and host rock. Cooling and depressurization of the TSX have not led to a significant increase in the number of MS or AE events. Ultrasonic results suggest the rock gets even stiffer

  3. Factors controlling the population size of microbes in groundwater from AECL's Underground Research Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Stroes-Gascoyne, S.; Hamon, C. [Atomic Energy of Canada Limited, Whiteshell Labs., Pinawa, Manitoba (Canada); Mills, K. [University of Saskatoon, Saskatoon, SK (Canada); Rana, S.; Vaidyanathan, S. [Deep River Science Academy, Whiteshell Campus Summer 1997, Pinawa, Manitoba (Canada)

    2001-01-01

    Microbial populations in groundwaters from AECL's Underground Research Laboratory (URL) range from 10{sup 3} to 10{sup 5} cells/mL. Based on the total dissolved organic carbon (DOC), nitrate and phosphate content of these waters, populations of about 10{sup 5} to 10{sup 7} cells/mL should be possible. Upon storage of groundwater samples, total cell counts generally increase and viable cell counts always increase. A study was undertaken to determine what controls the in situ microbial population size in groundwater and what causes this population to grow upon sampling. Fresh URL groundwater was filter-sterilized, inoculated with small quantities of the unaltered water and incubated in the absence and presence of added nutrients (nitrate, phosphate and glucose). Unfiltered groundwater and R2A growth medium inoculated with unaltered groundwater, were also incubated. Microbial changes over time were followed by total and viable (on R2A medium) cell counts. Results showed that in the absence of any nutrient addition, populations grew to between 5 x 10{sup 5} to 4 x 10{sup 6} cells/mL, regardless of the initial size of the population ({approx}10{sup 1} to 10{sup 4} cells/mL), suggesting that nutrients for growth were available in the unamended groundwater. It was hypothesized that the original groundwater population was in 'equilibrium' with the underground environment, which likely included a large population of sessile cells in biofilms on fracture surfaces. Sampling of the groundwater removed the large demand on nutrient supplies by the sessile population which subsequently allowed the planktonic population to grow to a new 'equilibrium' with the available nutrients in the sample bottles. Addition of single nutrients (C, N or P) did not increase cell numbers, suggesting that more than one nutrient is limiting growth. Glucose was used very efficiently aerobically in the presence of both added N and P, but somewhat less under anaerobic

  4. AECL present and future

    International Nuclear Information System (INIS)

    Foster, J.S.

    1975-08-01

    This is a history of Atomic Energy of Canada Limited with forecasts of its role in enabling Canada to meet a rapidly increasing share of her energy requirements from nuclear power. Its main activities will be research and development in support of contemporary and advanced CANDU (Canada Deuterium Uranium) nuclear power systems; research into other ways to provide energy and fissile materials; and investigation into applications for nuclear energy beyond the generation of electrical power. (Author)

  5. On the structure of Lattice code WIMSD-5B

    International Nuclear Information System (INIS)

    Kim, Won Young; Min, Byung Joo

    2004-03-01

    The WIMS-D code is a freely available thermal reactor physics lattice code used widely for thermal research and power reactor calculation. Now the code WIMS-AECL, developed on the basis of WIMS-D, has been used as one of lattice codes for the cell calculation in Canada and also, in 1998, the latest version WIMSD-5B is released for OECD/NEA Data Bank. While WIMS-KAERI was developed and has been used, originated from WIMS-D, in Korea, it was adjusted for the cell calculation of research reactor HANARO and so it has no confirmaty to CANDU reactor. Therefore, the code development applicable to cell calculation of CANDU reactor is necessary not only for technological independence and but also for the establishment of CANDU safety analysis system. A lattice code WIMSD-5B was analyzed in order to set the system of reactor physics computer codes, to be used in the assessment of void reactivity effect. In order to improve and validate WIMSD-5B code, the analysis of the structure of WIMSD-5B lattice code was made and so its structure, algorithm and the subroutines of WIMSD-5B were presented for the cluster type and the pij method modelling the CANDU-6 fuel

  6. Particle-tracking code (track3d) for convective solute transport modelling in the geosphere: Description and user`s manual; Programme de reperage de particules (track3d) pour la modelisation du transport par convection des solutes dans la geosphere: description et manuel de l`utilisateur

    Energy Technology Data Exchange (ETDEWEB)

    Nakka, B W; Chan, T

    1994-12-01

    A deterministic particle-tracking code (TRACK3D) has been developed to compute convective flow paths of conservative (nonreactive) contaminants through porous geological media. TRACK3D requires the groundwater velocity distribution, which, in our applications, results from flow simulations using AECL`s MOTIF code. The MOTIF finite-element code solves the transient and steady-state coupled equations of groundwater flow, solute transport and heat transport in fractured/porous media. With few modifications, TRACK3D can be used to analyse the velocity distributions calculated by other finite-element or finite-difference flow codes. This report describes the assumptions, limitations, organization, operation and applications of the TRACK3D code, and provides a comprehensive user`s manual.

  7. Past and future fracturing in AECL Research areas in the superior province of the Canadian Precambrian Shield, with emphasis on the Lac du Bonnet Batholith

    Energy Technology Data Exchange (ETDEWEB)

    Brown, A; Everitt, R A; Martin, C D; Davison, C C [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

    1995-10-01

    The likelihood that future fracturing, arising from geologic causes, could occur in the vicinity of a nuclear fuel waste repository in plutonic rock of the Canadian Precambrian Shield, is examined. The report discusses the possible causes of fracturing (both past and future) in Shield rocks. The report then examines case histories of fracture formation in Precambrian plutonic rocks in AECL`s Research Areas, especially the history of the Lac du Bonnet Batholith, in the Whiteshell Area, Manitoba. Initially, fractures can be introduced into intrusive plutonic rocks during crystallization and cooling of an intrusive magma. These fractures are found at all size scales; as late residual magma dyking, hydraulic fracturing by retrograde boiling off of hydrothermal fluids, and, in some cases, through local differential cooling. Subsequent fracturing is largely caused by changes in environmental temperature and stress field, rather than by alteration of the material behaviour of the rock. Pluton emplacement during orogeny is commonly accompanied by uplift and erosional exhumation, altering both the tectonic and the lithostatic stresses, the rock temperature gradient and the pore fluid characteristics.

  8. Coding Partitions

    Directory of Open Access Journals (Sweden)

    Fabio Burderi

    2007-05-01

    Full Text Available Motivated by the study of decipherability conditions for codes weaker than Unique Decipherability (UD, we introduce the notion of coding partition. Such a notion generalizes that of UD code and, for codes that are not UD, allows to recover the ``unique decipherability" at the level of the classes of the partition. By tacking into account the natural order between the partitions, we define the characteristic partition of a code X as the finest coding partition of X. This leads to introduce the canonical decomposition of a code in at most one unambiguouscomponent and other (if any totally ambiguouscomponents. In the case the code is finite, we give an algorithm for computing its canonical partition. This, in particular, allows to decide whether a given partition of a finite code X is a coding partition. This last problem is then approached in the case the code is a rational set. We prove its decidability under the hypothesis that the partition contains a finite number of classes and each class is a rational set. Moreover we conjecture that the canonical partition satisfies such a hypothesis. Finally we consider also some relationships between coding partitions and varieties of codes.

  9. Assessment of neutron transport codes for application to CANDU fuel lattices analysis

    International Nuclear Information System (INIS)

    Roh, Gyu Hong; Choi, Hang Bok

    1999-08-01

    In order to assess the applicability of WIMS-AECL and HELIOS code to the CANDU fuel lattice analysis, the physics calculations has been carried out for the standard CANDU fuel and DUPIC fuel lattices, and the results were compared with those of Monte Carlo code MCNP-4B. In this study, in order to consider the full isotopic composition and the temperature effect, new MCNP libraries have been generated from ENDF/B-VI release 3 and validated for typical benchmark problems. The TRX-1,2,BAPL-1,2,3 pin -cell lattices and KENO criticality safety benchmark calculations have been performed for the new MCNP libraries, and the results have shown that the new MCNP library has sufficient accuracy to be used for physics calculation. Then, the lattice codes have been benchmarked by the MCNP code for the major physics parameters such as the burnup reactivity, void reactivity, relative pin power and Doppler coefficient, etc. for the standard CANDU fuel and DUPIC fuel lattices. For the standard CANDU fuel lattice, it was found that the results of WIMS-AECL calculations are consistent with those of MCNP. For the DUPIC fuel lattice, however, the results of WIMS-AECL calculations with ENDF/B-V library have shown that the discrepancy from the results of MCNP calculations increases when the fuel burnup is relatively high. The burnup reactivities of WIMS-ACEL calculations with ENDF/B-VI library have shown excellent agreements with those of MCNP calculation for both the standard CANDU and DUPIC fuel lattices. However, the Doppler coefficient have relatively large discrepancies compared with MCNP calculations, and the difference increases as the fuel burns. On the other hand, the results of HELIOS calculation are consistent with those of MCNP even though the discrepancy is slightly larger compared with the case of the standard CANDU fuel lattice. this study has shown that the WIMS-AECL products reliable results for the natural uranium fuel. However, it is recommended that the WIMS

  10. The use of HANDIDET reg-sign non-electric detonator assemblies to reduce blast-induced overpressure at AECL's Underground Research Laboratory

    International Nuclear Information System (INIS)

    Onagi, D.P.; Keith, S.G.; Kuzyk, G.W.

    1996-01-01

    A number of aspects of the Canadian concept for nuclear fuel waste disposal are being assessed by Atomic Energy of Canada Limited (AECL) in a series of experiments at its Underground Research Laboratory (URL) near Lac du Bonnet, Manitoba, Canada. One of the major objectives of the work being carried out at the URL is to develop and evaluate the methods and technology to ensure safe, permanent disposal of Canada's nuclear fuel waste. In 1994, AECL excavated access tunnels and a laboratory room for the Quarried Block Fracture Migration Experiment (QBFME) at the 240 Level of the URL. This facility will be used to study the transport of radionuclides in natural fractures in quarried blocks of granite under in-situ groundwater conditions. The experiment is being carried out under a cooperative agreement with the Japan Atomic Energy Research Institute. The excavation of the QBFME access tunnels and laboratory was carried out using controlled blasting techniques that minimized blast-induced overpressure which could have damaged or interrupted other ongoing experiments in the vicinity. The majority of the blasts used conventional long delay non-electric detonators but a number of blasts were carried out using HANDIDET 250/6000 non-electric long delay detonator assemblies and HTD reg-sign non-electric short delay trunkline detonator assemblies. The tunnel and laboratory excavation was monitored to determine the levels of blast-induced overpressure. This paper describes the blasting and monitoring results of the blasts using HANDIDET non-electric detonator assemblies and the effectiveness of these detonators in reducing blast-induced overpressure

  11. Linking CATHENA with other computer codes through a remote process

    Energy Technology Data Exchange (ETDEWEB)

    Vasic, A.; Hanna, B.N.; Waddington, G.M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Sabourin, G. [Atomic Energy of Canada Limited, Montreal, Quebec (Canada); Girard, R. [Hydro-Quebec, Montreal, Quebec (Canada)

    2005-07-01

    'Full text:' CATHENA (Canadian Algorithm for THErmalhydraulic Network Analysis) is a computer code developed by Atomic Energy of Canada Limited (AECL). The code uses a transient, one-dimensional, two-fluid representation of two-phase flow in piping networks. CATHENA is used primarily for the analysis of postulated upset conditions in CANDU reactors; however, the code has found a wider range of applications. In the past, the CATHENA thermalhydraulics code included other specialized codes, i.e. ELOCA and the Point LEPreau CONtrol system (LEPCON) as callable subroutine libraries. The combined program was compiled and linked as a separately named code. This code organizational process is not suitable for independent development, maintenance, validation and version tracking of separate computer codes. The alternative solution to provide code development independence is to link CATHENA to other computer codes through a Parallel Virtual Machine (PVM) interface process. PVM is a public domain software package, developed by Oak Ridge National Laboratory and enables a heterogeneous collection of computers connected by a network to be used as a single large parallel machine. The PVM approach has been well accepted by the global computing community and has been used successfully for solving large-scale problems in science, industry, and business. Once development of the appropriate interface for linking independent codes through PVM is completed, future versions of component codes can be developed, distributed separately and coupled as needed by the user. This paper describes the coupling of CATHENA to the ELOCA-IST and the TROLG2 codes through a PVM remote process as an illustration of possible code connections. ELOCA (Element Loss Of Cooling Analysis) is the Industry Standard Toolset (IST) code developed by AECL to simulate the thermo-mechanical response of CANDU fuel elements to transient thermalhydraulics boundary conditions. A separate ELOCA driver program

  12. Linking CATHENA with other computer codes through a remote process

    International Nuclear Information System (INIS)

    Vasic, A.; Hanna, B.N.; Waddington, G.M.; Sabourin, G.; Girard, R.

    2005-01-01

    'Full text:' CATHENA (Canadian Algorithm for THErmalhydraulic Network Analysis) is a computer code developed by Atomic Energy of Canada Limited (AECL). The code uses a transient, one-dimensional, two-fluid representation of two-phase flow in piping networks. CATHENA is used primarily for the analysis of postulated upset conditions in CANDU reactors; however, the code has found a wider range of applications. In the past, the CATHENA thermalhydraulics code included other specialized codes, i.e. ELOCA and the Point LEPreau CONtrol system (LEPCON) as callable subroutine libraries. The combined program was compiled and linked as a separately named code. This code organizational process is not suitable for independent development, maintenance, validation and version tracking of separate computer codes. The alternative solution to provide code development independence is to link CATHENA to other computer codes through a Parallel Virtual Machine (PVM) interface process. PVM is a public domain software package, developed by Oak Ridge National Laboratory and enables a heterogeneous collection of computers connected by a network to be used as a single large parallel machine. The PVM approach has been well accepted by the global computing community and has been used successfully for solving large-scale problems in science, industry, and business. Once development of the appropriate interface for linking independent codes through PVM is completed, future versions of component codes can be developed, distributed separately and coupled as needed by the user. This paper describes the coupling of CATHENA to the ELOCA-IST and the TROLG2 codes through a PVM remote process as an illustration of possible code connections. ELOCA (Element Loss Of Cooling Analysis) is the Industry Standard Toolset (IST) code developed by AECL to simulate the thermo-mechanical response of CANDU fuel elements to transient thermalhydraulics boundary conditions. A separate ELOCA driver program starts, ends

  13. Speaking Code

    DEFF Research Database (Denmark)

    Cox, Geoff

    Speaking Code begins by invoking the “Hello World” convention used by programmers when learning a new language, helping to establish the interplay of text and code that runs through the book. Interweaving the voice of critical writing from the humanities with the tradition of computing and software...

  14. Verification of WIMS-ANL to be used as supporting code for WIMS-CANDU development

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Dai Hai; Kim, Won Young; Park, Joo Hwan

    2007-08-15

    The lattice code WIMS-ANL has been tested in order to assess it for the qualification to be used as a supporting code to aide the WIMS-CANDU development. A series of calculations have been performed to determine lattice physics parameters such as multiplication factors, isotopic number densities and coolant void reactivity. The WIMS-ANL results are compared with the predictions of WIMS-AECL/D4/D5 and PPV (POWDERPUFS-V), and the comparisons indicate that WIMS-ANL can be used not only as a supporting code to aide the WIMS-CANDU development, but also as a starting source for the study of developing detailed model that could delineate the realistic situations as it might occur during LOCA such as the asymmetric flux distribution across lattice cell.

  15. Development of 3-dimensional neutronics kinetics analysis code for CANDU-PHWR

    International Nuclear Information System (INIS)

    Kim, M. W.; Kim, C. H.; Hong, I. S.

    2005-02-01

    The followings are the major contents and scope of the research : development of kinetics power calculation module, formulation of space-dependent neutron transient analysis - implementation of 3-D and 2-G unified nodal method, verification of the kinetics module by benchmark problem - 3-D PHWR kinetics benchmark problem suggested by AECL, reactor trip simulation by shutdown system 1 in Wolsong unit 2. Development of a dynamic linked library code, SCAN D LL, for the coupled calculation with RELAP-CANDU : modeling of shutdown system 1, development of automatic shutdown module - automatic trip module based on rate log power control logic, automatic insertion of shutdown system 1. Development of a link code for coupled calculation - development of SCAN D LL(windows version), verification of coupled code by - 40% reactor inlet header break LOCA power pulse, 100% reactor outlet header break LOCA power pulse, 50% pump suction break LOCA power pulse

  16. Basic research and industrialization of CANDU advanced fuel - A research for the improvement of RFSP code

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hyo; Jang, Chang Sun; Han, Tae Young [Seoul National University, Seoul (Korea)

    2000-03-01

    The objective of this project is to improve the RFSP code by adopting three dimensional two neutron energy group model and accelerated iterative solution scheme (FDM3D) to 2 group diffusion equations as well. The major contents of this research are the derivation of the finite difference equation to three dimensional two neutron energy group diffusion equation, application of accelerated iterative solution scheme to the finite difference diffusion equation and validation of the improved RFSP code (FDM3D) through benchmark tests. We have shown that SOR/Chebyshev two parameter method and BICG-STAB/Wielandt method are more effective than that of RFSP in terms of computing speed. SOR/Chebyshev two parameter method shows better efficiency than BICG-STAB/Wielandt method. Because calculation efficiency of the latter depends on the right choice of pre-conditioner, however, it is considered that more studies are necessary to improve the efficiency of this latter method and to validate it. We have incorporated the new efficient method into the existing RFSP so that the resulting RFSP becomes much faster and more accurate. RFSP currently uses POWDERPUFS code as main lattice code, which is adequate to the neutron energy group model of RFSP. Because of this, we can not make the full advantage of advanced RFSP without adopting lattice code WIMS-AECL which can generate exact two neutron energy group constants. Therefore, we suggest developing a new CANDU design and analysis code which incorporate WIMS-AECL into FDM3D. 16 refs., 10 figs., 23 tabs. (Author)

  17. Development of Off-take Model, Subcooled Boiling Model, and Radiation Heat Transfer Input Model into the MARS Code for a Regulatory Auditing of CANDU Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, C.; Rhee, B. W.; Chung, B. D. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Ahn, S. H.; Kim, M. W. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2009-05-15

    Korea currently has four operating units of the CANDU-6 type reactor in Wolsong. However, the safety assessment system for CANDU reactors has not been fully established due to a lack of self-reliance technology. Although the CATHENA code had been introduced from AECL, it is undesirable to use a vendor's code for a regulatory auditing analysis. In Korea, the MARS code has been developed for decades and is being considered by KINS as a thermal hydraulic regulatory auditing tool for nuclear power plants. Before this decision, KINS (Korea Institute of Nuclear Safety) had developed the RELAP5/MOD3/CANDU code for CANDU safety analyses by modifying the model of the existing PWR auditing tool, RELAP5/MOD3. The main purpose of this study is to transplant the CANDU models of the RELAP5/MOD3/CANDU code to the MARS code including a quality assurance of the developed models.

  18. Development of Off-take Model, Subcooled Boiling Model, and Radiation Heat Transfer Input Model into the MARS Code for a Regulatory Auditing of CANDU Reactors

    International Nuclear Information System (INIS)

    Yoon, C.; Rhee, B. W.; Chung, B. D.; Ahn, S. H.; Kim, M. W.

    2009-01-01

    Korea currently has four operating units of the CANDU-6 type reactor in Wolsong. However, the safety assessment system for CANDU reactors has not been fully established due to a lack of self-reliance technology. Although the CATHENA code had been introduced from AECL, it is undesirable to use a vendor's code for a regulatory auditing analysis. In Korea, the MARS code has been developed for decades and is being considered by KINS as a thermal hydraulic regulatory auditing tool for nuclear power plants. Before this decision, KINS (Korea Institute of Nuclear Safety) had developed the RELAP5/MOD3/CANDU code for CANDU safety analyses by modifying the model of the existing PWR auditing tool, RELAP5/MOD3. The main purpose of this study is to transplant the CANDU models of the RELAP5/MOD3/CANDU code to the MARS code including a quality assurance of the developed models

  19. Coding Labour

    Directory of Open Access Journals (Sweden)

    Anthony McCosker

    2014-03-01

    Full Text Available As well as introducing the Coding Labour section, the authors explore the diffusion of code across the material contexts of everyday life, through the objects and tools of mediation, the systems and practices of cultural production and organisational management, and in the material conditions of labour. Taking code beyond computation and software, their specific focus is on the increasingly familiar connections between code and labour with a focus on the codification and modulation of affect through technologies and practices of management within the contemporary work organisation. In the grey literature of spreadsheets, minutes, workload models, email and the like they identify a violence of forms through which workplace affect, in its constant flux of crisis and ‘prodromal’ modes, is regulated and governed.

  20. Past and future fracturing in AECL Research areas in the superior province of the Canadian Precambrian Shield, with emphasis on the Lac du Bonnet Batholith

    International Nuclear Information System (INIS)

    Brown, A.; Everitt, R.A.; Martin, C.D.; Davison, C.C.

    1995-10-01

    The likelihood that future fracturing, arising from geologic causes, could occur in the vicinity of a nuclear fuel waste repository in plutonic rock of the Canadian Precambrian Shield, is examined. The report discusses the possible causes of fracturing (both past and future) in Shield rocks. The report then examines case histories of fracture formation in Precambrian plutonic rocks in AECL's Research Areas, especially the history of the Lac du Bonnet Batholith, in the Whiteshell Area, Manitoba. Initially, fractures can be introduced into intrusive plutonic rocks during crystallization and cooling of an intrusive magma. These fractures are found at all size scales; as late residual magma dyking, hydraulic fracturing by retrograde boiling off of hydrothermal fluids, and, in some cases, through local differential cooling. Subsequent fracturing is largely caused by changes in environmental temperature and stress field, rather than by alteration of the material behaviour of the rock. Pluton emplacement during orogeny is commonly accompanied by uplift and erosional exhumation, altering both the tectonic and the lithostatic stresses, the rock temperature gradient and the pore fluid characteristics

  1. The large-scale vented combustion test facility at AECL-WL: description and preliminary test results

    International Nuclear Information System (INIS)

    Loesel Sitar, J.; Koroll, G.W.; Dewit, W.A.; Bowles, E.M.; Harding, J.; Sabanski, C.L.; Kumar, R.K.

    1997-01-01

    Implementation of hydrogen mitigation systems in nuclear reactor containments requires testing the effectiveness of the mitigation system, reliability and availability of the hardware, potential consequences of its use and the technical basis for hardware placement, on a meaningful scale. Similarly, the development and validation of containment codes used in nuclear reactor safety analysis require detailed combustion data from medium- and large-scale facilities. A Large-Scale Combustion Test Facility measuring 10 m x 4 m x 3 m (volume, 120 m 3 ) has been constructed and commissioned at Whiteshell Laboratories to perform a wide variety of combustion experiments. The facility is designed to be versatile so that many geometrical configurations can be achieved. The facility incorporates extensive capabilities for instrumentation and high speed data acquisition, on-line gas sampling and analysis. Other features of the facility include operation at elevated temperatures up to 150 degrees C, easy access to the interior, and remote operation. Initial thermodynamic conditions in the facility can be controlled to within 0.1 vol% of constituent gases. The first series of experiments examined vented combustion in the full 120 m 3 -volume configuration with vent areas in the range of 0.56 to 2.24 m 2 . The experiments were performed at ∼27 degrees C and near-atmospheric pressures, with hydrogen concentrations in the range of 8 to 12% by volume. This paper describes the Large-Scale Vented Combustion Test Facility and preliminary results from the first series of experiments. (author)

  2. Speech coding

    Energy Technology Data Exchange (ETDEWEB)

    Ravishankar, C., Hughes Network Systems, Germantown, MD

    1998-05-08

    Speech is the predominant means of communication between human beings and since the invention of the telephone by Alexander Graham Bell in 1876, speech services have remained to be the core service in almost all telecommunication systems. Original analog methods of telephony had the disadvantage of speech signal getting corrupted by noise, cross-talk and distortion Long haul transmissions which use repeaters to compensate for the loss in signal strength on transmission links also increase the associated noise and distortion. On the other hand digital transmission is relatively immune to noise, cross-talk and distortion primarily because of the capability to faithfully regenerate digital signal at each repeater purely based on a binary decision. Hence end-to-end performance of the digital link essentially becomes independent of the length and operating frequency bands of the link Hence from a transmission point of view digital transmission has been the preferred approach due to its higher immunity to noise. The need to carry digital speech became extremely important from a service provision point of view as well. Modem requirements have introduced the need for robust, flexible and secure services that can carry a multitude of signal types (such as voice, data and video) without a fundamental change in infrastructure. Such a requirement could not have been easily met without the advent of digital transmission systems, thereby requiring speech to be coded digitally. The term Speech Coding is often referred to techniques that represent or code speech signals either directly as a waveform or as a set of parameters by analyzing the speech signal. In either case, the codes are transmitted to the distant end where speech is reconstructed or synthesized using the received set of codes. A more generic term that is applicable to these techniques that is often interchangeably used with speech coding is the term voice coding. This term is more generic in the sense that the

  3. Optimal codes as Tanner codes with cyclic component codes

    DEFF Research Database (Denmark)

    Høholdt, Tom; Pinero, Fernando; Zeng, Peng

    2014-01-01

    In this article we study a class of graph codes with cyclic code component codes as affine variety codes. Within this class of Tanner codes we find some optimal binary codes. We use a particular subgraph of the point-line incidence plane of A(2,q) as the Tanner graph, and we are able to describe ...

  4. Aztheca Code

    International Nuclear Information System (INIS)

    Quezada G, S.; Espinosa P, G.; Centeno P, J.; Sanchez M, H.

    2017-09-01

    This paper presents the Aztheca code, which is formed by the mathematical models of neutron kinetics, power generation, heat transfer, core thermo-hydraulics, recirculation systems, dynamic pressure and level models and control system. The Aztheca code is validated with plant data, as well as with predictions from the manufacturer when the reactor operates in a stationary state. On the other hand, to demonstrate that the model is applicable during a transient, an event occurred in a nuclear power plant with a BWR reactor is selected. The plant data are compared with the results obtained with RELAP-5 and the Aztheca model. The results show that both RELAP-5 and the Aztheca code have the ability to adequately predict the behavior of the reactor. (Author)

  5. Vocable Code

    DEFF Research Database (Denmark)

    Soon, Winnie; Cox, Geoff

    2018-01-01

    a computational and poetic composition for two screens: on one of these, texts and voices are repeated and disrupted by mathematical chaos, together exploring the performativity of code and language; on the other, is a mix of a computer programming syntax and human language. In this sense queer code can...... be understood as both an object and subject of study that intervenes in the world’s ‘becoming' and how material bodies are produced via human and nonhuman practices. Through mixing the natural and computer language, this article presents a script in six parts from a performative lecture for two persons...

  6. NSURE code

    International Nuclear Information System (INIS)

    Rattan, D.S.

    1993-11-01

    NSURE stands for Near-Surface Repository code. NSURE is a performance assessment code. developed for the safety assessment of near-surface disposal facilities for low-level radioactive waste (LLRW). Part one of this report documents the NSURE model, governing equations and formulation of the mathematical models, and their implementation under the SYVAC3 executive. The NSURE model simulates the release of nuclides from an engineered vault, their subsequent transport via the groundwater and surface water pathways tot he biosphere, and predicts the resulting dose rate to a critical individual. Part two of this report consists of a User's manual, describing simulation procedures, input data preparation, output and example test cases

  7. The Aster code; Code Aster

    Energy Technology Data Exchange (ETDEWEB)

    Delbecq, J.M

    1999-07-01

    The Aster code is a 2D or 3D finite-element calculation code for structures developed by the R and D direction of Electricite de France (EdF). This dossier presents a complete overview of the characteristics and uses of the Aster code: introduction of version 4; the context of Aster (organisation of the code development, versions, systems and interfaces, development tools, quality assurance, independent validation); static mechanics (linear thermo-elasticity, Euler buckling, cables, Zarka-Casier method); non-linear mechanics (materials behaviour, big deformations, specific loads, unloading and loss of load proportionality indicators, global algorithm, contact and friction); rupture mechanics (G energy restitution level, restitution level in thermo-elasto-plasticity, 3D local energy restitution level, KI and KII stress intensity factors, calculation of limit loads for structures), specific treatments (fatigue, rupture, wear, error estimation); meshes and models (mesh generation, modeling, loads and boundary conditions, links between different modeling processes, resolution of linear systems, display of results etc..); vibration mechanics (modal and harmonic analysis, dynamics with shocks, direct transient dynamics, seismic analysis and aleatory dynamics, non-linear dynamics, dynamical sub-structuring); fluid-structure interactions (internal acoustics, mass, rigidity and damping); linear and non-linear thermal analysis; steels and metal industry (structure transformations); coupled problems (internal chaining, internal thermo-hydro-mechanical coupling, chaining with other codes); products and services. (J.S.)

  8. Coding Class

    DEFF Research Database (Denmark)

    Ejsing-Duun, Stine; Hansbøl, Mikala

    Denne rapport rummer evaluering og dokumentation af Coding Class projektet1. Coding Class projektet blev igangsat i skoleåret 2016/2017 af IT-Branchen i samarbejde med en række medlemsvirksomheder, Københavns kommune, Vejle Kommune, Styrelsen for IT- og Læring (STIL) og den frivillige forening...... Coding Pirates2. Rapporten er forfattet af Docent i digitale læringsressourcer og forskningskoordinator for forsknings- og udviklingsmiljøet Digitalisering i Skolen (DiS), Mikala Hansbøl, fra Institut for Skole og Læring ved Professionshøjskolen Metropol; og Lektor i læringsteknologi, interaktionsdesign......, design tænkning og design-pædagogik, Stine Ejsing-Duun fra Forskningslab: It og Læringsdesign (ILD-LAB) ved Institut for kommunikation og psykologi, Aalborg Universitet i København. Vi har fulgt og gennemført evaluering og dokumentation af Coding Class projektet i perioden november 2016 til maj 2017...

  9. Uplink Coding

    Science.gov (United States)

    Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

    2007-01-01

    This slide presentation reviews the objectives, meeting goals and overall NASA goals for the NASA Data Standards Working Group. The presentation includes information on the technical progress surrounding the objective, short LDPC codes, and the general results on the Pu-Pw tradeoff.

  10. ANIMAL code

    International Nuclear Information System (INIS)

    Lindemuth, I.R.

    1979-01-01

    This report describes ANIMAL, a two-dimensional Eulerian magnetohydrodynamic computer code. ANIMAL's physical model also appears. Formulated are temporal and spatial finite-difference equations in a manner that facilitates implementation of the algorithm. Outlined are the functions of the algorithm's FORTRAN subroutines and variables

  11. Network Coding

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 7. Network Coding. K V Rashmi Nihar B Shah P Vijay Kumar. General Article Volume 15 Issue 7 July 2010 pp 604-621. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/015/07/0604-0621 ...

  12. MCNP code

    International Nuclear Information System (INIS)

    Cramer, S.N.

    1984-01-01

    The MCNP code is the major Monte Carlo coupled neutron-photon transport research tool at the Los Alamos National Laboratory, and it represents the most extensive Monte Carlo development program in the United States which is available in the public domain. The present code is the direct descendent of the original Monte Carlo work of Fermi, von Neumaum, and Ulam at Los Alamos in the 1940s. Development has continued uninterrupted since that time, and the current version of MCNP (or its predecessors) has always included state-of-the-art methods in the Monte Carlo simulation of radiation transport, basic cross section data, geometry capability, variance reduction, and estimation procedures. The authors of the present code have oriented its development toward general user application. The documentation, though extensive, is presented in a clear and simple manner with many examples, illustrations, and sample problems. In addition to providing the desired results, the output listings give a a wealth of detailed information (some optional) concerning each state of the calculation. The code system is continually updated to take advantage of advances in computer hardware and software, including interactive modes of operation, diagnostic interrupts and restarts, and a variety of graphical and video aids

  13. Expander Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Expander Codes - The Sipser–Spielman Construction. Priti Shankar. General Article Volume 10 ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science Bangalore 560 012, India.

  14. AECL's use of FMEA and OPEX for field service tooling and process development, implementation and improvement: a model for the future

    International Nuclear Information System (INIS)

    Cox, E.; Dam, R.F.; Wilson, E.

    2008-01-01

    Failure Modes and Effects Analysis (FMEA) is a systematic and rigorous process applied to new or complex systems to predict system failures and assist with the development of mitigating strategies. The process is especially beneficial when applied to higher-risk applications such as nuclear systems. FMEA may be used for design verification and maintenance program development. For field service tooling, FMEA is complimented well by operating experience (OPEX) and continuous improvement initiatives. FMEA is generally conducted while developing systems and processes to ensure safe and successful implementation, while OPEX is fed back into the system design and operation to improve those systems and processes for subsequent field applications. This paper will explore these techniques as they have been applied to AECL's CANDUclean system. The portable CANDUclean system is employed to mechanically clean the inside of steam generator (SG) tubes in CANDU nuclear power plants. During normal plant operation, the steam generator tubes in the heat transport system develop a build-up of magnetite on their internal diameter, which decreases heat transfer efficiency, impedes SG maintenance activities and increases the radiation fields in and around the boilers. As part of a regular plant aging management routine, the CANDUclean system is used to remove the magnetite layers. The nature of this work includes risks to personnel safety, however by continually applying FMEA and other improvement initiatives, safety and system effectiveness are maximized. This paper will provide an overview of the integrated continuous improvement approach applied to the CANDUclean system and consider the value of strategies when applied to field service tooling and CANDU systems. (author)

  15. Results of a survey on accident and safety analysis codes, benchmarks, verification and validation methods

    International Nuclear Information System (INIS)

    Lee, A.G.; Wilkin, G.B.

    1996-03-01

    During the 'Workshop on R and D needs' at the 3rd Meeting of the International Group on Research Reactors (IGORR-III), the participants agreed that it would be useful to compile a survey of the computer codes and nuclear data libraries used in accident and safety analyses for research reactors and the methods various organizations use to verify and validate their codes and libraries. Five organizations, Atomic Energy of Canada Limited (AECL, Canada), China Institute of Atomic Energy (CIAE, People's Republic of China), Japan Atomic Energy Research Institute (JAERI, Japan), Oak Ridge National Laboratories (ORNL, USA), and Siemens (Germany) responded to the survey. The results of the survey are compiled in this report. (author) 36 refs., 3 tabs

  16. Development of best estimate auditing code for CANDU thermal hydraulic safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B. D.; Lee, W. J.; Lim, H. S. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-04-15

    The main purpose of this study is to develop a thermal hydraulic auditing code for the CANDU reactor, modifying the model of existing PWR auditing tool, i.e. RELAP5/MOD3. This scope of project is first step of the whole project, thus focus to the establishment of improvement area. The study was performed by reconsideration of the previous code assessment works and investigation of AECL design analysis tools. In order to identify the thermal hydraulic phenomena for events, the whole system of CANDU plant was divided into main functional systems and subcomponents. Each phenomena was addressed to the each subcomponent. FinaIly improvement areas of model development for auditing tool were established based on the identified phenomena.

  17. A SciCode web site: building bridges between owners and users

    Energy Technology Data Exchange (ETDEWEB)

    Gaver, C. [Atomic Energy of Canada Ltd., Mississauga, Ontario (Canada)

    2000-07-01

    Web technology is a tool that is gaining in popularity. Properly used, it is a powerful tool that has tremendous potential for providing better communication. It can also be effective as a training tool, an information-sharing tool, and as a means of simplifying work load, and facilitating compliance with Company procedures. The issue is one of communication. The challenge facing many large or geographically-distributed companies is how to communicate information to their staff and to their customers. Procedures overseeing quality-assurance programs and commitment to ensuring the quality of products need to be communicated to customers. Equally important is customer feedback. This information from users becomes the kernel for future product development. The issue is even more important when speaking of scientific analysis computer programs (SciCodes). Regular ongoing communication between Primary Holders and End Users is essential in the development and use of SciCodes. Without this communication, quality assurance is at risk. Quality assurance processes are an integral part in developing any SciCode. End Users also have a role to play. Primary Holders keep End Users informed of improvements or new releases. End Users must ensure they act on this information. Equally important, End Users must communicate problems or suggestions to the Primary Holder to remedy or incorporate in new releases. In other words, quality assurance processes become most effective when both Primary Holder and End Users are involved. This requires communication. Web technology offers AECL a means of providing regular, ongoing communication between its scientific-code (SciCode) Primary Holders-Owner Branches and the End Users of these codes within and outside the Company. Using the experience we have gained by developing the Y2K SciCode Web sites, setting up online documentation systems, and incorporating lessons learned from the Y2K project we have developed a model that is geared to

  18. A SciCode web site: building bridges between owners and users

    International Nuclear Information System (INIS)

    Gaver, C.

    2000-01-01

    Web technology is a tool that is gaining in popularity. Properly used, it is a powerful tool that has tremendous potential for providing better communication. It can also be effective as a training tool, an information-sharing tool, and as a means of simplifying work load, and facilitating compliance with Company procedures. The issue is one of communication. The challenge facing many large or geographically-distributed companies is how to communicate information to their staff and to their customers. Procedures overseeing quality-assurance programs and commitment to ensuring the quality of products need to be communicated to customers. Equally important is customer feedback. This information from users becomes the kernel for future product development. The issue is even more important when speaking of scientific analysis computer programs (SciCodes). Regular ongoing communication between Primary Holders and End Users is essential in the development and use of SciCodes. Without this communication, quality assurance is at risk. Quality assurance processes are an integral part in developing any SciCode. End Users also have a role to play. Primary Holders keep End Users informed of improvements or new releases. End Users must ensure they act on this information. Equally important, End Users must communicate problems or suggestions to the Primary Holder to remedy or incorporate in new releases. In other words, quality assurance processes become most effective when both Primary Holder and End Users are involved. This requires communication. Web technology offers AECL a means of providing regular, ongoing communication between its scientific-code (SciCode) Primary Holders-Owner Branches and the End Users of these codes within and outside the Company. Using the experience we have gained by developing the Y2K SciCode Web sites, setting up online documentation systems, and incorporating lessons learned from the Y2K project we have developed a model that is geared to

  19. Panda code

    International Nuclear Information System (INIS)

    Altomare, S.; Minton, G.

    1975-02-01

    PANDA is a new two-group one-dimensional (slab/cylinder) neutron diffusion code designed to replace and extend the FAB series. PANDA allows for the nonlinear effects of xenon, enthalpy and Doppler. Fuel depletion is allowed. PANDA has a completely general search facility which will seek criticality, maximize reactivity, or minimize peaking. Any single parameter may be varied in a search. PANDA is written in FORTRAN IV, and as such is nearly machine independent. However, PANDA has been written with the present limitations of the Westinghouse CDC-6600 system in mind. Most computation loops are very short, and the code is less than half the useful 6600 memory size so that two jobs can reside in the core at once. (auth)

  20. CANAL code

    International Nuclear Information System (INIS)

    Gara, P.; Martin, E.

    1983-01-01

    The CANAL code presented here optimizes a realistic iron free extraction channel which has to provide a given transversal magnetic field law in the median plane: the current bars may be curved, have finite lengths and cooling ducts and move in a restricted transversal area; terminal connectors may be added, images of the bars in pole pieces may be included. A special option optimizes a real set of circular coils [fr

  1. From concatenated codes to graph codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom

    2004-01-01

    We consider codes based on simple bipartite expander graphs. These codes may be seen as the first step leading from product type concatenated codes to more complex graph codes. We emphasize constructions of specific codes of realistic lengths, and study the details of decoding by message passing...

  2. A benchmark comparison of the Canadian Supercritical Water-Cooled Reactor (SCWR) 64-element fuel lattice cell parameters using various computer codes

    International Nuclear Information System (INIS)

    Sharpe, J.; Salaun, F.; Hummel, D.; Moghrabi, A.; Nowak, M.; Pencer, J.; Novog, D.; Buijs, A.

    2015-01-01

    Discrepancies in key lattice physics parameters have been observed between various deterministic (e.g. DRAGON and WIMS-AECL) and stochastic (MCNP, KENO) neutron transport codes in modeling previous versions of the Canadian SCWR lattice cell. Further, inconsistencies in these parameters have also been observed when using different nuclear data libraries. In this work, the predictions of k∞, various reactivity coefficients, and relative ring-averaged pin powers have been re-evaluated using these codes and libraries with the most recent 64-element fuel assembly geometry. A benchmark problem has been defined to quantify the dissimilarities between code results for a number of responses along the fuel channel under prescribed hot full power (HFP), hot zero power (HZP) and cold zero power (CZP) conditions and at several fuel burnups (0, 25 and 50 MW·d·kg"-"1 [HM]). Results from deterministic (TRITON, DRAGON) and stochastic codes (MCNP6, KENO V.a and KENO-VI) are presented. (author)

  3. MOX fuel fabrication at AECL

    International Nuclear Information System (INIS)

    Dimayuga, F.C.; Jeffs, A.T.

    1995-01-01

    Atomic Energy of Canada Limited's mixed-oxide (MOX) fuel fabrication activities are conducted in the Recycle Fuel Fabrication Laboratories (RFFL) at the Chalk River Laboratories. The RFFL facility is designed to produce experimental quantities of CANDU MOX fuel for reactor physics tests or demonstration irradiations. From 1979 to 1987, several MOX fuel fabrication campaigns were run in the RFFL, producing various quantities of fuel with different compositions. About 150 bundles, containing over three tonnes of MOX, were fabricated in the RFFL before operations in the facility were suspended. In late 1987, the RFFL was placed in a state of active standby, a condition where no fuel fabrication activities are conducted, but the monitoring and ventilation systems in the facility are maintained. Currently, a project to rehabilitate the RFFL and resume MOX fuel fabrication is nearing completion. This project is funded by the CANDU Owners' Group (COG). The initial fabrication campaign will consist of the production of thirty-eight 37-element (U,Pu)O 2 bundles containing 0.2 wt% Pu in Heavy Element (H.E.) destined for physics tests in the zero-power ZED-2 reactor. An overview of the Rehabilitation Project will be given. (author)

  4. Rock stability considerations for siting and constructing a KBS-3 repository. Based on experiences from Aespoe HRL, AECL's URL, tunnelling and mining

    Energy Technology Data Exchange (ETDEWEB)

    Martin, C.D. [Univ. of Alberta, Edmonton (Canada); Christiansson, Rolf [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Soederhaell, J. [VBB VIAK AB, Stockholm (Sweden)

    2001-12-01

    Over the past 25 years the international nuclear community has carried out extensive research into the deep geological disposal of nuclear waste in hard rocks. In two cases this research has resulted in the construction of dedicated underground research facilities: SKB's Aespoe Hard Rock Laboratory, Sweden and AECL's Underground Research Laboratory, Canada. Both laboratories are located in hard rocks considered representative of the Fennoscandian and Canadian Shields, respectively. This report is intended to synthesize the important rock mechanics findings from these research programs. In particular the application of these finding to assessing the stability of underground openings. As such the report draws heavily on the published results from the SKB's ZEDEX Experiment in Sweden and AECL's Mine- by Experiment in Canada. The objectives of this report are to: 1. Describe, using the current state of knowledge, the role rock engineering can play in siting and constructing a KBS-3 repository. 2. Define the key rock mechanics parameters that should be determined in order to facilitate repository siting and construction. 3. Discuss possible construction issues, linked to rock stability, that may arise during the excavation of the underground openings of a KBS-3 repository. 4. Form a reference document for the rock stability analysis that has to be carried out as a part of the design works parallel to the site investigations. While there is no unique or single rock mechanics property or condition that would render the performance of a nuclear waste repository unacceptable, certain conditions can be treated as negative factors. Outlined below are major rock mechanics issues that should be addressed during the siting, construction and closure of a nuclear waste repository in Sweden in hard crystalline rock. During the site investigations phase, rock mechanics information will be predominately gathered from examination and testing of the rock core and

  5. Rock stability considerations for siting and constructing a KBS-3 repository. Based on experiences from Aespoe HRL, AECL's URL, tunnelling and mining

    International Nuclear Information System (INIS)

    Martin, C.D.; Christiansson, Rolf; Soederhaell, J.

    2001-12-01

    Over the past 25 years the international nuclear community has carried out extensive research into the deep geological disposal of nuclear waste in hard rocks. In two cases this research has resulted in the construction of dedicated underground research facilities: SKB's Aespoe Hard Rock Laboratory, Sweden and AECL's Underground Research Laboratory, Canada. Both laboratories are located in hard rocks considered representative of the Fennoscandian and Canadian Shields, respectively. This report is intended to synthesize the important rock mechanics findings from these research programs. In particular the application of these finding to assessing the stability of underground openings. As such the report draws heavily on the published results from the SKB's ZEDEX Experiment in Sweden and AECL's Mine- by Experiment in Canada. The objectives of this report are to: 1. Describe, using the current state of knowledge, the role rock engineering can play in siting and constructing a KBS-3 repository. 2. Define the key rock mechanics parameters that should be determined in order to facilitate repository siting and construction. 3. Discuss possible construction issues, linked to rock stability, that may arise during the excavation of the underground openings of a KBS-3 repository. 4. Form a reference document for the rock stability analysis that has to be carried out as a part of the design works parallel to the site investigations. While there is no unique or single rock mechanics property or condition that would render the performance of a nuclear waste repository unacceptable, certain conditions can be treated as negative factors. Outlined below are major rock mechanics issues that should be addressed during the siting, construction and closure of a nuclear waste repository in Sweden in hard crystalline rock. During the site investigations phase, rock mechanics information will be predominately gathered from examination and testing of the rock core and mapping of the

  6. Verification of the MOTIF code version 3.0

    International Nuclear Information System (INIS)

    Chan, T.; Guvanasen, V.; Nakka, B.W.; Reid, J.A.K.; Scheier, N.W.; Stanchell, F.W.

    1996-12-01

    As part of the Canadian Nuclear Fuel Waste Management Program (CNFWMP), AECL has developed a three-dimensional finite-element code, MOTIF (Model Of Transport In Fractured/ porous media), for detailed modelling of groundwater flow, heat transport and solute transport in a fractured rock mass. The code solves the transient and steady-state equations of groundwater flow, solute (including one-species radionuclide) transport, and heat transport in variably saturated fractured/porous media. The initial development was completed in 1985 (Guvanasen 1985) and version 3.0 was completed in 1986. This version is documented in detail in Guvanasen and Chan (in preparation). This report describes a series of fourteen verification cases which has been used to test the numerical solution techniques and coding of MOTIF, as well as demonstrate some of the MOTIF analysis capabilities. For each case the MOTIF solution has been compared with a corresponding analytical or independently developed alternate numerical solution. Several of the verification cases were included in Level 1 of the International Hydrologic Code Intercomparison Project (HYDROCOIN). The MOTIF results for these cases were also described in the HYDROCOIN Secretariat's compilation and comparison of results submitted by the various project teams (Swedish Nuclear Power Inspectorate 1988). It is evident from the graphical comparisons presented that the MOTIF solutions for the fourteen verification cases are generally in excellent agreement with known analytical or numerical solutions obtained from independent sources. This series of verification studies has established the ability of the MOTIF finite-element code to accurately model the groundwater flow and solute and heat transport phenomena for which it is intended. (author). 20 refs., 14 tabs., 32 figs

  7. Automatic coding method of the ACR Code

    International Nuclear Information System (INIS)

    Park, Kwi Ae; Ihm, Jong Sool; Ahn, Woo Hyun; Baik, Seung Kook; Choi, Han Yong; Kim, Bong Gi

    1993-01-01

    The authors developed a computer program for automatic coding of ACR(American College of Radiology) code. The automatic coding of the ACR code is essential for computerization of the data in the department of radiology. This program was written in foxbase language and has been used for automatic coding of diagnosis in the Department of Radiology, Wallace Memorial Baptist since May 1992. The ACR dictionary files consisted of 11 files, one for the organ code and the others for the pathology code. The organ code was obtained by typing organ name or code number itself among the upper and lower level codes of the selected one that were simultaneous displayed on the screen. According to the first number of the selected organ code, the corresponding pathology code file was chosen automatically. By the similar fashion of organ code selection, the proper pathologic dode was obtained. An example of obtained ACR code is '131.3661'. This procedure was reproducible regardless of the number of fields of data. Because this program was written in 'User's Defined Function' from, decoding of the stored ACR code was achieved by this same program and incorporation of this program into program in to another data processing was possible. This program had merits of simple operation, accurate and detail coding, and easy adjustment for another program. Therefore, this program can be used for automation of routine work in the department of radiology

  8. Error-correction coding

    Science.gov (United States)

    Hinds, Erold W. (Principal Investigator)

    1996-01-01

    This report describes the progress made towards the completion of a specific task on error-correcting coding. The proposed research consisted of investigating the use of modulation block codes as the inner code of a concatenated coding system in order to improve the overall space link communications performance. The study proposed to identify and analyze candidate codes that will complement the performance of the overall coding system which uses the interleaved RS (255,223) code as the outer code.

  9. Development of best estimate auditing code for CANDU thermal hydraulic safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B. D.; Lee, W. J.; Lim, H. S. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2000-03-15

    The main purpose of this study is to develop a thermal hydraulic auditing code for the CANDU reactor, modifying the model if existing PWR auditing tool, i.e. RELAP5/MOD3. This scope of project is a third step of the whole project, and expand the RELAP5/MOD3/CANDU version for implementation of LOCA analysis. There are three main area of model development, i.e. moody critical flow model, flow regime model of horizontal CANDU bundle, and fuel element heatup model when the stratification occurs. Newly developed version, namely RELAP5/MOD3/CANDU+ is applicable to CANDU plant analysis with keeping the function of light water reactor analysis. The limited validations of model installation were performed. Assessment of CHF model using AECL separated effect test and calculation for Wolsong 2 plant were performed also for the applicability test of the developed version.

  10. Development of a best estimate auditing code for CANDU thermal hydraulic safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B.D.; Lee, W.J.; Lim, H.S. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-03-01

    The main purpose of this study is to develop a thermal hydraulic auditing code for the CANDU reactor, modifying the model of existing PWR auditing tool , i.e. RELAP5/MOD3. This scope of project is a third step of the whole project, and expand the RELAP5/MOD3/CANDU version for implementation of LOCA Analysis. There are three main area of model development, i.e. Moody critical flow model, flow regime model of horizontal CANDU bundle, and fuel element heatup model when the stratification occurs. Newly developed version, namely RELAP5/MOD3/CANDU+ is applicable to CANDU plant analysis with keeping the function of light water reactor analysis. The limited validations of model installation were performed. Assessment of CHF model using AECL separated effect test and calculation for Wolsong 2 plant were performed also for the applicability test of the developed version. 15 refs., 37 figs., 8 tabs. (Author)

  11. Dynamic Shannon Coding

    OpenAIRE

    Gagie, Travis

    2005-01-01

    We present a new algorithm for dynamic prefix-free coding, based on Shannon coding. We give a simple analysis and prove a better upper bound on the length of the encoding produced than the corresponding bound for dynamic Huffman coding. We show how our algorithm can be modified for efficient length-restricted coding, alphabetic coding and coding with unequal letter costs.

  12. Fundamentals of convolutional coding

    CERN Document Server

    Johannesson, Rolf

    2015-01-01

    Fundamentals of Convolutional Coding, Second Edition, regarded as a bible of convolutional coding brings you a clear and comprehensive discussion of the basic principles of this field * Two new chapters on low-density parity-check (LDPC) convolutional codes and iterative coding * Viterbi, BCJR, BEAST, list, and sequential decoding of convolutional codes * Distance properties of convolutional codes * Includes a downloadable solutions manual

  13. Codes Over Hyperfields

    Directory of Open Access Journals (Sweden)

    Atamewoue Surdive

    2017-12-01

    Full Text Available In this paper, we define linear codes and cyclic codes over a finite Krasner hyperfield and we characterize these codes by their generator matrices and parity check matrices. We also demonstrate that codes over finite Krasner hyperfields are more interesting for code theory than codes over classical finite fields.

  14. Vector Network Coding Algorithms

    OpenAIRE

    Ebrahimi, Javad; Fragouli, Christina

    2010-01-01

    We develop new algebraic algorithms for scalar and vector network coding. In vector network coding, the source multicasts information by transmitting vectors of length L, while intermediate nodes process and combine their incoming packets by multiplying them with L x L coding matrices that play a similar role as coding c in scalar coding. Our algorithms for scalar network jointly optimize the employed field size while selecting the coding coefficients. Similarly, for vector coding, our algori...

  15. Homological stabilizer codes

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Jonas T., E-mail: jonastyleranderson@gmail.com

    2013-03-15

    In this paper we define homological stabilizer codes on qubits which encompass codes such as Kitaev's toric code and the topological color codes. These codes are defined solely by the graphs they reside on. This feature allows us to use properties of topological graph theory to determine the graphs which are suitable as homological stabilizer codes. We then show that all toric codes are equivalent to homological stabilizer codes on 4-valent graphs. We show that the topological color codes and toric codes correspond to two distinct classes of graphs. We define the notion of label set equivalencies and show that under a small set of constraints the only homological stabilizer codes without local logical operators are equivalent to Kitaev's toric code or to the topological color codes. - Highlights: Black-Right-Pointing-Pointer We show that Kitaev's toric codes are equivalent to homological stabilizer codes on 4-valent graphs. Black-Right-Pointing-Pointer We show that toric codes and color codes correspond to homological stabilizer codes on distinct graphs. Black-Right-Pointing-Pointer We find and classify all 2D homological stabilizer codes. Black-Right-Pointing-Pointer We find optimal codes among the homological stabilizer codes.

  16. Diagnostic Coding for Epilepsy.

    Science.gov (United States)

    Williams, Korwyn; Nuwer, Marc R; Buchhalter, Jeffrey R

    2016-02-01

    Accurate coding is an important function of neurologic practice. This contribution to Continuum is part of an ongoing series that presents helpful coding information along with examples related to the issue topic. Tips for diagnosis coding, Evaluation and Management coding, procedure coding, or a combination are presented, depending on which is most applicable to the subject area of the issue.

  17. Coding of Neuroinfectious Diseases.

    Science.gov (United States)

    Barkley, Gregory L

    2015-12-01

    Accurate coding is an important function of neurologic practice. This contribution to Continuum is part of an ongoing series that presents helpful coding information along with examples related to the issue topic. Tips for diagnosis coding, Evaluation and Management coding, procedure coding, or a combination are presented, depending on which is most applicable to the subject area of the issue.

  18. Intercomparison and validation of computer codes for thermalhydraulic safety analysis of heavy water reactors

    International Nuclear Information System (INIS)

    2004-08-01

    Activities within the frame of the IAEA's Technical Working Group on Advanced Technologies for HWRs (TWG-HWR) are conducted in a project within the IAEA's subprogramme on nuclear power reactor technology development. The objective of the activities on HWRs is to foster, within the frame of the TWG-HWR, information exchange and co-operative research on technology development for current and future HWRs, with an emphasis on safety, economics and fuel resource sustainability. One of the activities recommended by the TWG-HWR was an international standard problem exercise entitled: Intercomparison and validation of computer codes for thermalhydraulics safety analyses. Intercomparison and validation of computer codes used in different countries for thermalhydraulics safety analyses will enhance the confidence in the predictions made by these codes. However, the intercomparison and validation exercise needs a set of reliable experimental data. The RD-14M Large-Loss Of Coolant Accident (LOCA) test B9401 simulating HWR LOCA behaviour that was conducted by Atomic Energy of Canada Ltd (AECL) was selected for this validation project. This report provides a comparison of the results obtained from six participating countries, utilizing four different computer codes. General conclusions are reached and recommendations made

  19. Comparison of Heavy Water Reactor Thermalhydraulic Code Predictions with Small Break LOCA Experimental Data

    International Nuclear Information System (INIS)

    2012-08-01

    Activities within the frame of the IAEA's Technical Working Group on Advanced Technologies for HWRs (TWG-HWR) are conducted in a project within the IAEA's subprogramme on nuclear power reactor technology development. The objective of the activities on HWRs is to foster, within the frame of the TWG-HWR, information exchange and cooperative research on technology development for current and future HWRs, with an emphasis on safety, economics and fuel resource sustainability. One of the activities recommended by the TWG-HWR was an international standard problem exercise entitled Intercomparison and Validation of Computer Codes for Thermalhydraulics Safety Analyses. Intercomparison and validation of computer codes used in different countries for thermalhydraulics safety analyses will enhance the confidence in the predictions made by these codes. However, the intercomparison and validation exercise needs a set of reliable experimental data. Two RD-14M small break loss of coolant accident (SBLOCA) tests, simulating HWR LOCA behaviour, conducted by Atomic Energy of Canada Ltd (AECL), were selected for this validation project. This report provides a comparison of the results obtained from eight participating organizations from six countries (Argentina, Canada, China, India, Republic of Korea, and Romania), utilizing four different computer codes (ATMIKA, CATHENA, MARS-KS, and RELAP5). General conclusions are reached and recommendations made.

  20. Vector Network Coding

    OpenAIRE

    Ebrahimi, Javad; Fragouli, Christina

    2010-01-01

    We develop new algebraic algorithms for scalar and vector network coding. In vector network coding, the source multicasts information by transmitting vectors of length L, while intermediate nodes process and combine their incoming packets by multiplying them with L X L coding matrices that play a similar role as coding coefficients in scalar coding. Our algorithms for scalar network jointly optimize the employed field size while selecting the coding coefficients. Similarly, for vector co...

  1. Entropy Coding in HEVC

    OpenAIRE

    Sze, Vivienne; Marpe, Detlev

    2014-01-01

    Context-Based Adaptive Binary Arithmetic Coding (CABAC) is a method of entropy coding first introduced in H.264/AVC and now used in the latest High Efficiency Video Coding (HEVC) standard. While it provides high coding efficiency, the data dependencies in H.264/AVC CABAC make it challenging to parallelize and thus limit its throughput. Accordingly, during the standardization of entropy coding for HEVC, both aspects of coding efficiency and throughput were considered. This chapter describes th...

  2. Generalized concatenated quantum codes

    International Nuclear Information System (INIS)

    Grassl, Markus; Shor, Peter; Smith, Graeme; Smolin, John; Zeng Bei

    2009-01-01

    We discuss the concept of generalized concatenated quantum codes. This generalized concatenation method provides a systematical way for constructing good quantum codes, both stabilizer codes and nonadditive codes. Using this method, we construct families of single-error-correcting nonadditive quantum codes, in both binary and nonbinary cases, which not only outperform any stabilizer codes for finite block length but also asymptotically meet the quantum Hamming bound for large block length.

  3. Rateless feedback codes

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Koike-Akino, Toshiaki; Orlik, Philip

    2012-01-01

    This paper proposes a concept called rateless feedback coding. We redesign the existing LT and Raptor codes, by introducing new degree distributions for the case when a few feedback opportunities are available. We show that incorporating feedback to LT codes can significantly decrease both...... the coding overhead and the encoding/decoding complexity. Moreover, we show that, at the price of a slight increase in the coding overhead, linear complexity is achieved with Raptor feedback coding....

  4. Advanced video coding systems

    CERN Document Server

    Gao, Wen

    2015-01-01

    This comprehensive and accessible text/reference presents an overview of the state of the art in video coding technology. Specifically, the book introduces the tools of the AVS2 standard, describing how AVS2 can help to achieve a significant improvement in coding efficiency for future video networks and applications by incorporating smarter coding tools such as scene video coding. Topics and features: introduces the basic concepts in video coding, and presents a short history of video coding technology and standards; reviews the coding framework, main coding tools, and syntax structure of AV

  5. Coding for dummies

    CERN Document Server

    Abraham, Nikhil

    2015-01-01

    Hands-on exercises help you learn to code like a pro No coding experience is required for Coding For Dummies,your one-stop guide to building a foundation of knowledge inwriting computer code for web, application, and softwaredevelopment. It doesn't matter if you've dabbled in coding or neverwritten a line of code, this book guides you through the basics.Using foundational web development languages like HTML, CSS, andJavaScript, it explains in plain English how coding works and whyit's needed. Online exercises developed by Codecademy, a leading online codetraining site, help hone coding skill

  6. Discussion on LDPC Codes and Uplink Coding

    Science.gov (United States)

    Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

    2007-01-01

    This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

  7. Locally orderless registration code

    DEFF Research Database (Denmark)

    2012-01-01

    This is code for the TPAMI paper "Locally Orderless Registration". The code requires intel threadding building blocks installed and is provided for 64 bit on mac, linux and windows.......This is code for the TPAMI paper "Locally Orderless Registration". The code requires intel threadding building blocks installed and is provided for 64 bit on mac, linux and windows....

  8. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    Shannon limit of the channel. Among the earliest discovered codes that approach the. Shannon limit were the low density parity check (LDPC) codes. The term low density arises from the property of the parity check matrix defining the code. We will now define this matrix and the role that it plays in decoding. 2. Linear Codes.

  9. Manually operated coded switch

    International Nuclear Information System (INIS)

    Barnette, J.H.

    1978-01-01

    The disclosure related to a manually operated recodable coded switch in which a code may be inserted, tried and used to actuate a lever controlling an external device. After attempting a code, the switch's code wheels must be returned to their zero positions before another try is made

  10. Coding in Muscle Disease.

    Science.gov (United States)

    Jones, Lyell K; Ney, John P

    2016-12-01

    Accurate coding is critically important for clinical practice and research. Ongoing changes to diagnostic and billing codes require the clinician to stay abreast of coding updates. Payment for health care services, data sets for health services research, and reporting for medical quality improvement all require accurate administrative coding. This article provides an overview of administrative coding for patients with muscle disease and includes a case-based review of diagnostic and Evaluation and Management (E/M) coding principles in patients with myopathy. Procedural coding for electrodiagnostic studies and neuromuscular ultrasound is also reviewed.

  11. QR Codes 101

    Science.gov (United States)

    Crompton, Helen; LaFrance, Jason; van 't Hooft, Mark

    2012-01-01

    A QR (quick-response) code is a two-dimensional scannable code, similar in function to a traditional bar code that one might find on a product at the supermarket. The main difference between the two is that, while a traditional bar code can hold a maximum of only 20 digits, a QR code can hold up to 7,089 characters, so it can contain much more…

  12. N286.7-99, A Canadian standard specifying software quality management system requirements for analytical, scientific, and design computer programs and its implementation at AECL

    International Nuclear Information System (INIS)

    Abel, R.

    2000-01-01

    Analytical, scientific, and design computer programs (referred to in this paper as 'scientific computer programs') are developed for use in a large number of ways by the user-engineer to support and prove engineering calculations and assumptions. These computer programs are subject to frequent modifications inherent in their application and are often used for critical calculations and analysis relative to safety and functionality of equipment and systems. N286.7-99(4) was developed to establish appropriate quality management system requirements to deal with the development, modification, and application of scientific computer programs. N286.7-99 provides particular guidance regarding the treatment of legacy codes

  13. The European source-term evaluation code ASTEC: status and applications, including CANDU plant applications

    International Nuclear Information System (INIS)

    Van Dorsselaere, J.P.; Giordano, P.; Kissane, M.P.; Montanelli, T.; Schwinges, B.; Ganju, S.; Dickson, L.

    2004-01-01

    Research on light-water reactor severe accidents (SA) is still required in a limited number of areas in order to confirm accident-management plans. Thus, 49 European organizations have linked their SA research in a durable way through SARNET (Severe Accident Research and management NETwork), part of the European 6th Framework Programme. One goal of SARNET is to consolidate the integral code ASTEC (Accident Source Term Evaluation Code, developed by IRSN and GRS) as the European reference tool for safety studies; SARNET efforts include extending the application scope to reactor types other than PWR (including VVER) such as BWR and CANDU. ASTEC is used in IRSN's Probabilistic Safety Analysis level 2 of 900 MWe French PWRs. An earlier version of ASTEC's SOPHAEROS module, including improvements by AECL, is being validated as the Canadian Industry Standard Toolset code for FP-transport analysis in the CANDU Heat Transport System. Work with ASTEC has also been performed by Bhabha Atomic Research Centre, Mumbai, on IPHWR containment thermal hydraulics. (author)

  14. Source-term model for the SYVAC3-NSURE performance assessment code

    International Nuclear Information System (INIS)

    Rowat, J.H.; Rattan, D.S.; Dolinar, G.M.

    1996-11-01

    Radionuclide contaminants in wastes emplaced in disposal facilities will not remain in those facilities indefinitely. Engineered barriers will eventually degrade, allowing radioactivity to escape from the vault. The radionuclide release rate from a low-level radioactive waste (LLRW) disposal facility, the source term, is a key component in the performance assessment of the disposal system. This report describes the source-term model that has been implemented in Ver. 1.03 of the SYVAC3-NSURE (Systems Variability Analysis Code generation 3-Near Surface Repository) code. NSURE is a performance assessment code that evaluates the impact of near-surface disposal of LLRW through the groundwater pathway. The source-term model described here was developed for the Intrusion Resistant Underground Structure (IRUS) disposal facility, which is a vault that is to be located in the unsaturated overburden at AECL's Chalk River Laboratories. The processes included in the vault model are roof and waste package performance, and diffusion, advection and sorption of radionuclides in the vault backfill. The model presented here was developed for the IRUS vault; however, it is applicable to other near-surface disposal facilities. (author). 40 refs., 6 figs

  15. Computation of a Canadian SCWR unit cell with deterministic and Monte Carlo codes

    International Nuclear Information System (INIS)

    Harrisson, G.; Marleau, G.

    2012-01-01

    The Canadian SCWR has the potential to achieve the goals that the generation IV nuclear reactors must meet. As part of the optimization process for this design concept, lattice cell calculations are routinely performed using deterministic codes. In this study, the first step (self-shielding treatment) of the computation scheme developed with the deterministic code DRAGON for the Canadian SCWR has been validated. Some options available in the module responsible for the resonance self-shielding calculation in DRAGON 3.06 and different microscopic cross section libraries based on the ENDF/B-VII.0 evaluated nuclear data file have been tested and compared to a reference calculation performed with the Monte Carlo code SERPENT under the same conditions. Compared to SERPENT, DRAGON underestimates the infinite multiplication factor in all cases. In general, the original Stammler model with the Livolant-Jeanpierre approximations are the most appropriate self-shielding options to use in this case of study. In addition, the 89 groups WIMS-AECL library for slight enriched uranium and the 172 groups WLUP library for a mixture of plutonium and thorium give the most consistent results with those of SERPENT. (authors)

  16. Codes and curves

    CERN Document Server

    Walker, Judy L

    2000-01-01

    When information is transmitted, errors are likely to occur. Coding theory examines efficient ways of packaging data so that these errors can be detected, or even corrected. The traditional tools of coding theory have come from combinatorics and group theory. Lately, however, coding theorists have added techniques from algebraic geometry to their toolboxes. In particular, by re-interpreting the Reed-Solomon codes, one can see how to define new codes based on divisors on algebraic curves. For instance, using modular curves over finite fields, Tsfasman, Vladut, and Zink showed that one can define a sequence of codes with asymptotically better parameters than any previously known codes. This monograph is based on a series of lectures the author gave as part of the IAS/PCMI program on arithmetic algebraic geometry. Here, the reader is introduced to the exciting field of algebraic geometric coding theory. Presenting the material in the same conversational tone of the lectures, the author covers linear codes, inclu...

  17. The materiality of Code

    DEFF Research Database (Denmark)

    Soon, Winnie

    2014-01-01

    This essay studies the source code of an artwork from a software studies perspective. By examining code that come close to the approach of critical code studies (Marino, 2006), I trace the network artwork, Pupufu (Lin, 2009) to understand various real-time approaches to social media platforms (MSN......, Twitter and Facebook). The focus is not to investigate the functionalities and efficiencies of the code, but to study and interpret the program level of code in order to trace the use of various technological methods such as third-party libraries and platforms’ interfaces. These are important...... to understand the socio-technical side of a changing network environment. Through the study of code, including but not limited to source code, technical specifications and other materials in relation to the artwork production, I would like to explore the materiality of code that goes beyond technical...

  18. Coding for optical channels

    CERN Document Server

    Djordjevic, Ivan; Vasic, Bane

    2010-01-01

    This unique book provides a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory and optical communication.

  19. SEVERO code - user's manual

    International Nuclear Information System (INIS)

    Sacramento, A.M. do.

    1989-01-01

    This user's manual contains all the necessary information concerning the use of SEVERO code. This computer code is related to the statistics of extremes = extreme winds, extreme precipitation and flooding hazard risk analysis. (A.C.A.S.)

  20. Synthesizing Certified Code

    OpenAIRE

    Whalen, Michael; Schumann, Johann; Fischer, Bernd

    2002-01-01

    Code certification is a lightweight approach for formally demonstrating software quality. Its basic idea is to require code producers to provide formal proofs that their code satisfies certain quality properties. These proofs serve as certificates that can be checked independently. Since code certification uses the same underlying technology as program verification, it requires detailed annotations (e.g., loop invariants) to make the proofs possible. However, manually adding annotations to th...

  1. FERRET data analysis code

    International Nuclear Information System (INIS)

    Schmittroth, F.

    1979-09-01

    A documentation of the FERRET data analysis code is given. The code provides a way to combine related measurements and calculations in a consistent evaluation. Basically a very general least-squares code, it is oriented towards problems frequently encountered in nuclear data and reactor physics. A strong emphasis is on the proper treatment of uncertainties and correlations and in providing quantitative uncertainty estimates. Documentation includes a review of the method, structure of the code, input formats, and examples

  2. Stylize Aesthetic QR Code

    OpenAIRE

    Xu, Mingliang; Su, Hao; Li, Yafei; Li, Xi; Liao, Jing; Niu, Jianwei; Lv, Pei; Zhou, Bing

    2018-01-01

    With the continued proliferation of smart mobile devices, Quick Response (QR) code has become one of the most-used types of two-dimensional code in the world. Aiming at beautifying the appearance of QR codes, existing works have developed a series of techniques to make the QR code more visual-pleasant. However, these works still leave much to be desired, such as visual diversity, aesthetic quality, flexibility, universal property, and robustness. To address these issues, in this paper, we pro...

  3. Enhancing QR Code Security

    OpenAIRE

    Zhang, Linfan; Zheng, Shuang

    2015-01-01

    Quick Response code opens possibility to convey data in a unique way yet insufficient prevention and protection might lead into QR code being exploited on behalf of attackers. This thesis starts by presenting a general introduction of background and stating two problems regarding QR code security, which followed by a comprehensive research on both QR code itself and related issues. From the research a solution taking advantages of cloud and cryptography together with an implementation come af...

  4. Opening up codings?

    DEFF Research Database (Denmark)

    Steensig, Jakob; Heinemann, Trine

    2015-01-01

    doing formal coding and when doing more “traditional” conversation analysis research based on collections. We are more wary, however, of the implication that coding-based research is the end result of a process that starts with qualitative investigations and ends with categories that can be coded...

  5. Gauge color codes

    DEFF Research Database (Denmark)

    Bombin Palomo, Hector

    2015-01-01

    Color codes are topological stabilizer codes with unusual transversality properties. Here I show that their group of transversal gates is optimal and only depends on the spatial dimension, not the local geometry. I also introduce a generalized, subsystem version of color codes. In 3D they allow...

  6. Refactoring test code

    NARCIS (Netherlands)

    A. van Deursen (Arie); L.M.F. Moonen (Leon); A. van den Bergh; G. Kok

    2001-01-01

    textabstractTwo key aspects of extreme programming (XP) are unit testing and merciless refactoring. Given the fact that the ideal test code / production code ratio approaches 1:1, it is not surprising that unit tests are being refactored. We found that refactoring test code is different from

  7. Software Certification - Coding, Code, and Coders

    Science.gov (United States)

    Havelund, Klaus; Holzmann, Gerard J.

    2011-01-01

    We describe a certification approach for software development that has been adopted at our organization. JPL develops robotic spacecraft for the exploration of the solar system. The flight software that controls these spacecraft is considered to be mission critical. We argue that the goal of a software certification process cannot be the development of "perfect" software, i.e., software that can be formally proven to be correct under all imaginable and unimaginable circumstances. More realistically, the goal is to guarantee a software development process that is conducted by knowledgeable engineers, who follow generally accepted procedures to control known risks, while meeting agreed upon standards of workmanship. We target three specific issues that must be addressed in such a certification procedure: the coding process, the code that is developed, and the skills of the coders. The coding process is driven by standards (e.g., a coding standard) and tools. The code is mechanically checked against the standard with the help of state-of-the-art static source code analyzers. The coders, finally, are certified in on-site training courses that include formal exams.

  8. The network code

    International Nuclear Information System (INIS)

    1997-01-01

    The Network Code defines the rights and responsibilities of all users of the natural gas transportation system in the liberalised gas industry in the United Kingdom. This report describes the operation of the Code, what it means, how it works and its implications for the various participants in the industry. The topics covered are: development of the competitive gas market in the UK; key points in the Code; gas transportation charging; impact of the Code on producers upstream; impact on shippers; gas storage; supply point administration; impact of the Code on end users; the future. (20 tables; 33 figures) (UK)

  9. Coding for Electronic Mail

    Science.gov (United States)

    Rice, R. F.; Lee, J. J.

    1986-01-01

    Scheme for coding facsimile messages promises to reduce data transmission requirements to one-tenth current level. Coding scheme paves way for true electronic mail in which handwritten, typed, or printed messages or diagrams sent virtually instantaneously - between buildings or between continents. Scheme, called Universal System for Efficient Electronic Mail (USEEM), uses unsupervised character recognition and adaptive noiseless coding of text. Image quality of resulting delivered messages improved over messages transmitted by conventional coding. Coding scheme compatible with direct-entry electronic mail as well as facsimile reproduction. Text transmitted in this scheme automatically translated to word-processor form.

  10. NAGRADATA. Code key. Geology

    International Nuclear Information System (INIS)

    Mueller, W.H.; Schneider, B.; Staeuble, J.

    1984-01-01

    This reference manual provides users of the NAGRADATA system with comprehensive keys to the coding/decoding of geological and technical information to be stored in or retreaved from the databank. Emphasis has been placed on input data coding. When data is retreaved the translation into plain language of stored coded information is done automatically by computer. Three keys each, list the complete set of currently defined codes for the NAGRADATA system, namely codes with appropriate definitions, arranged: 1. according to subject matter (thematically) 2. the codes listed alphabetically and 3. the definitions listed alphabetically. Additional explanation is provided for the proper application of the codes and the logic behind the creation of new codes to be used within the NAGRADATA system. NAGRADATA makes use of codes instead of plain language for data storage; this offers the following advantages: speed of data processing, mainly data retrieval, economies of storage memory requirements, the standardisation of terminology. The nature of this thesaurian type 'key to codes' makes it impossible to either establish a final form or to cover the entire spectrum of requirements. Therefore, this first issue of codes to NAGRADATA must be considered to represent the current state of progress of a living system and future editions will be issued in a loose leave ringbook system which can be updated by an organised (updating) service. (author)

  11. XSOR codes users manual

    International Nuclear Information System (INIS)

    Jow, Hong-Nian; Murfin, W.B.; Johnson, J.D.

    1993-11-01

    This report describes the source term estimation codes, XSORs. The codes are written for three pressurized water reactors (Surry, Sequoyah, and Zion) and two boiling water reactors (Peach Bottom and Grand Gulf). The ensemble of codes has been named ''XSOR''. The purpose of XSOR codes is to estimate the source terms which would be released to the atmosphere in severe accidents. A source term includes the release fractions of several radionuclide groups, the timing and duration of releases, the rates of energy release, and the elevation of releases. The codes have been developed by Sandia National Laboratories for the US Nuclear Regulatory Commission (NRC) in support of the NUREG-1150 program. The XSOR codes are fast running parametric codes and are used as surrogates for detailed mechanistic codes. The XSOR codes also provide the capability to explore the phenomena and their uncertainty which are not currently modeled by the mechanistic codes. The uncertainty distributions of input parameters may be used by an. XSOR code to estimate the uncertainty of source terms

  12. Reactor lattice codes

    International Nuclear Information System (INIS)

    Kulikowska, T.

    1999-01-01

    The present lecture has a main goal to show how the transport lattice calculations are realised in a standard computer code. This is illustrated on the example of the WIMSD code, belonging to the most popular tools for reactor calculations. Most of the approaches discussed here can be easily modified to any other lattice code. The description of the code assumes the basic knowledge of reactor lattice, on the level given in the lecture on 'Reactor lattice transport calculations'. For more advanced explanation of the WIMSD code the reader is directed to the detailed descriptions of the code cited in References. The discussion of the methods and models included in the code is followed by the generally used homogenisation procedure and several numerical examples of discrepancies in calculated multiplication factors based on different sources of library data. (author)

  13. DLLExternalCode

    Energy Technology Data Exchange (ETDEWEB)

    2014-05-14

    DLLExternalCode is the a general dynamic-link library (DLL) interface for linking GoldSim (www.goldsim.com) with external codes. The overall concept is to use GoldSim as top level modeling software with interfaces to external codes for specific calculations. The DLLExternalCode DLL that performs the linking function is designed to take a list of code inputs from GoldSim, create an input file for the external application, run the external code, and return a list of outputs, read from files created by the external application, back to GoldSim. Instructions for creating the input file, running the external code, and reading the output are contained in an instructions file that is read and interpreted by the DLL.

  14. Implementation of Wolsong Pump Model, Pressure Tube Deformation Model and Off-take Model into MARS Code for Regulatory Auditing of CANDU Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, C.; Rhee, B. W.; Chung, B. D. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Cho, Y. J.; Kim, M. W. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2008-05-15

    Korea currently has four operating units of the CANDU-6 type reactor in Wolsong. However, the safety assessment system for CANDU reactors has not been fully established due to lack of self-reliance technology. Although the CATHENA code had been introduced from AECL, it is undesirable to use vendor's code for regulatory auditing analysis. In Korea, the MARS code has been developed for decades and is being considered by KINS as a thermal hydraulic regulatory auditing tool for nuclear power plants. Before this decision, KINS (Korea Institute of Nuclear Safety) had developed RELAP5/MOD3/CANDU code for CANDU safety analyses by modifying the model of existing PWR auditing tool, RELAP5/MOD3. The main purpose of this study is to transplant the CANDU models of RELAP5/MOD3/CANDU code to MARS code including quality assurance of the developed models. This first part of the research series presents the implementation and verification of the Wolsong pump model, the pressure tube deformation model, and the off-take model for arbitrary-angled branch pipes.

  15. Implementation of Wolsong Pump Model, Pressure Tube Deformation Model and Off-take Model into MARS Code for Regulatory Auditing of CANDU Reactors

    International Nuclear Information System (INIS)

    Yoon, C.; Rhee, B. W.; Chung, B. D.; Cho, Y. J.; Kim, M. W.

    2008-01-01

    Korea currently has four operating units of the CANDU-6 type reactor in Wolsong. However, the safety assessment system for CANDU reactors has not been fully established due to lack of self-reliance technology. Although the CATHENA code had been introduced from AECL, it is undesirable to use vendor's code for regulatory auditing analysis. In Korea, the MARS code has been developed for decades and is being considered by KINS as a thermal hydraulic regulatory auditing tool for nuclear power plants. Before this decision, KINS (Korea Institute of Nuclear Safety) had developed RELAP5/MOD3/CANDU code for CANDU safety analyses by modifying the model of existing PWR auditing tool, RELAP5/MOD3. The main purpose of this study is to transplant the CANDU models of RELAP5/MOD3/CANDU code to MARS code including quality assurance of the developed models. This first part of the research series presents the implementation and verification of the Wolsong pump model, the pressure tube deformation model, and the off-take model for arbitrary-angled branch pipes

  16. ASSERT-PV 3.2: Advanced subchannel thermalhydraulics code for CANDU fuel bundles

    International Nuclear Information System (INIS)

    Rao, Y.F.; Cheng, Z.; Waddington, G.M.; Nava-Dominguez, A.

    2014-01-01

    Highlights: • Introduction to a new version of the Canadian subchannel code, ASSERT-PV 3.2. • Enhanced models for flow-distribution, CHF and post-dryout heat transfer prediction. • Model changes focused on unique features of horizontal CANDU bundles. • Detailed description of model changes for all major thermalhydraulics models. • Discussion on rationale and limitation of the model changes. - Abstract: Atomic Energy of Canada Limited (AECL) has developed the subchannel thermalhydraulics code ASSERT-PV for the Canadian nuclear industry. The most recent release version, ASSERT-PV 3.2 has enhanced phenomenon models for improved predictions of flow distribution, dryout power and CHF location, and post-dryout (PDO) sheath temperature in horizontal CANDU fuel bundles. The focus of the improvements is mainly on modeling considerations for the unique features of CANDU bundles such as horizontal flows, small pitch to diameter ratios, high mass fluxes, and mixed and irregular subchannel geometries, compared to PWR/BWR fuel assemblies. This paper provides a general introduction to ASSERT-PV 3.2, and describes the model changes or additions in the new version to improve predictions of flow distribution, dryout power and CHF location, and PDO sheath temperatures in CANDU fuel bundles

  17. ASSERT-PV 3.2: Advanced subchannel thermalhydraulics code for CANDU fuel bundles

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Y.F., E-mail: raoy@aecl.ca; Cheng, Z., E-mail: chengz@aecl.ca; Waddington, G.M., E-mail: waddingg@aecl.ca; Nava-Dominguez, A., E-mail: navadoma@aecl.ca

    2014-08-15

    Highlights: • Introduction to a new version of the Canadian subchannel code, ASSERT-PV 3.2. • Enhanced models for flow-distribution, CHF and post-dryout heat transfer prediction. • Model changes focused on unique features of horizontal CANDU bundles. • Detailed description of model changes for all major thermalhydraulics models. • Discussion on rationale and limitation of the model changes. - Abstract: Atomic Energy of Canada Limited (AECL) has developed the subchannel thermalhydraulics code ASSERT-PV for the Canadian nuclear industry. The most recent release version, ASSERT-PV 3.2 has enhanced phenomenon models for improved predictions of flow distribution, dryout power and CHF location, and post-dryout (PDO) sheath temperature in horizontal CANDU fuel bundles. The focus of the improvements is mainly on modeling considerations for the unique features of CANDU bundles such as horizontal flows, small pitch to diameter ratios, high mass fluxes, and mixed and irregular subchannel geometries, compared to PWR/BWR fuel assemblies. This paper provides a general introduction to ASSERT-PV 3.2, and describes the model changes or additions in the new version to improve predictions of flow distribution, dryout power and CHF location, and PDO sheath temperatures in CANDU fuel bundles.

  18. Toric Varieties and Codes, Error-correcting Codes, Quantum Codes, Secret Sharing and Decoding

    DEFF Research Database (Denmark)

    Hansen, Johan Peder

    We present toric varieties and associated toric codes and their decoding. Toric codes are applied to construct Linear Secret Sharing Schemes (LSSS) with strong multiplication by the Massey construction. Asymmetric Quantum Codes are obtained from toric codes by the A.R. Calderbank P.W. Shor and A.......M. Steane construction of stabilizer codes (CSS) from linear codes containing their dual codes....

  19. An Optimal Linear Coding for Index Coding Problem

    OpenAIRE

    Pezeshkpour, Pouya

    2015-01-01

    An optimal linear coding solution for index coding problem is established. Instead of network coding approach by focus on graph theoric and algebraic methods a linear coding program for solving both unicast and groupcast index coding problem is presented. The coding is proved to be the optimal solution from the linear perspective and can be easily utilize for any number of messages. The importance of this work is lying mostly on the usage of the presented coding in the groupcast index coding ...

  20. The Aesthetics of Coding

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik

    2007-01-01

    Computer art is often associated with computer-generated expressions (digitally manipulated audio/images in music, video, stage design, media facades, etc.). In recent computer art, however, the code-text itself – not the generated output – has become the artwork (Perl Poetry, ASCII Art, obfuscated...... code, etc.). The presentation relates this artistic fascination of code to a media critique expressed by Florian Cramer, claiming that the graphical interface represents a media separation (of text/code and image) causing alienation to the computer’s materiality. Cramer is thus the voice of a new ‘code...... avant-garde’. In line with Cramer, the artists Alex McLean and Adrian Ward (aka Slub) declare: “art-oriented programming needs to acknowledge the conditions of its own making – its poesis.” By analysing the Live Coding performances of Slub (where they program computer music live), the presentation...

  1. Majorana fermion codes

    International Nuclear Information System (INIS)

    Bravyi, Sergey; Terhal, Barbara M; Leemhuis, Bernhard

    2010-01-01

    We initiate the study of Majorana fermion codes (MFCs). These codes can be viewed as extensions of Kitaev's one-dimensional (1D) model of unpaired Majorana fermions in quantum wires to higher spatial dimensions and interacting fermions. The purpose of MFCs is to protect quantum information against low-weight fermionic errors, that is, operators acting on sufficiently small subsets of fermionic modes. We examine to what extent MFCs can surpass qubit stabilizer codes in terms of their stability properties. A general construction of 2D MFCs is proposed that combines topological protection based on a macroscopic code distance with protection based on fermionic parity conservation. Finally, we use MFCs to show how to transform any qubit stabilizer code to a weakly self-dual CSS code.

  2. Theory of epigenetic coding.

    Science.gov (United States)

    Elder, D

    1984-06-07

    The logic of genetic control of development may be based on a binary epigenetic code. This paper revises the author's previous scheme dealing with the numerology of annelid metamerism in these terms. Certain features of the code had been deduced to be combinatorial, others not. This paradoxical contrast is resolved here by the interpretation that these features relate to different operations of the code; the combinatiorial to coding identity of units, the non-combinatorial to coding production of units. Consideration of a second paradox in the theory of epigenetic coding leads to a new solution which further provides a basis for epimorphic regeneration, and may in particular throw light on the "regeneration-duplication" phenomenon. A possible test of the model is also put forward.

  3. DISP1 code

    International Nuclear Information System (INIS)

    Vokac, P.

    1999-12-01

    DISP1 code is a simple tool for assessment of the dispersion of the fission product cloud escaping from a nuclear power plant after an accident. The code makes it possible to tentatively check the feasibility of calculations by more complex PSA3 codes and/or codes for real-time dispersion calculations. The number of input parameters is reasonably low and the user interface is simple enough to allow a rapid processing of sensitivity analyses. All input data entered through the user interface are stored in the text format. Implementation of dispersion model corrections taken from the ARCON96 code enables the DISP1 code to be employed for assessment of the radiation hazard within the NPP area, in the control room for instance. (P.A.)

  4. Phonological coding during reading.

    Science.gov (United States)

    Leinenger, Mallorie

    2014-11-01

    The exact role that phonological coding (the recoding of written, orthographic information into a sound based code) plays during silent reading has been extensively studied for more than a century. Despite the large body of research surrounding the topic, varying theories as to the time course and function of this recoding still exist. The present review synthesizes this body of research, addressing the topics of time course and function in tandem. The varying theories surrounding the function of phonological coding (e.g., that phonological codes aid lexical access, that phonological codes aid comprehension and bolster short-term memory, or that phonological codes are largely epiphenomenal in skilled readers) are first outlined, and the time courses that each maps onto (e.g., that phonological codes come online early [prelexical] or that phonological codes come online late [postlexical]) are discussed. Next the research relevant to each of these proposed functions is reviewed, discussing the varying methodologies that have been used to investigate phonological coding (e.g., response time methods, reading while eye-tracking or recording EEG and MEG, concurrent articulation) and highlighting the advantages and limitations of each with respect to the study of phonological coding. In response to the view that phonological coding is largely epiphenomenal in skilled readers, research on the use of phonological codes in prelingually, profoundly deaf readers is reviewed. Finally, implications for current models of word identification (activation-verification model, Van Orden, 1987; dual-route model, e.g., M. Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001; parallel distributed processing model, Seidenberg & McClelland, 1989) are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  5. The aeroelastic code FLEXLAST

    Energy Technology Data Exchange (ETDEWEB)

    Visser, B. [Stork Product Eng., Amsterdam (Netherlands)

    1996-09-01

    To support the discussion on aeroelastic codes, a description of the code FLEXLAST was given and experiences within benchmarks and measurement programmes were summarized. The code FLEXLAST has been developed since 1982 at Stork Product Engineering (SPE). Since 1992 FLEXLAST has been used by Dutch industries for wind turbine and rotor design. Based on the comparison with measurements, it can be concluded that the main shortcomings of wind turbine modelling lie in the field of aerodynamics, wind field and wake modelling. (au)

  6. MORSE Monte Carlo code

    International Nuclear Information System (INIS)

    Cramer, S.N.

    1984-01-01

    The MORSE code is a large general-use multigroup Monte Carlo code system. Although no claims can be made regarding its superiority in either theoretical details or Monte Carlo techniques, MORSE has been, since its inception at ORNL in the late 1960s, the most widely used Monte Carlo radiation transport code. The principal reason for this popularity is that MORSE is relatively easy to use, independent of any installation or distribution center, and it can be easily customized to fit almost any specific need. Features of the MORSE code are described

  7. QR codes for dummies

    CERN Document Server

    Waters, Joe

    2012-01-01

    Find out how to effectively create, use, and track QR codes QR (Quick Response) codes are popping up everywhere, and businesses are reaping the rewards. Get in on the action with the no-nonsense advice in this streamlined, portable guide. You'll find out how to get started, plan your strategy, and actually create the codes. Then you'll learn to link codes to mobile-friendly content, track your results, and develop ways to give your customers value that will keep them coming back. It's all presented in the straightforward style you've come to know and love, with a dash of humor thrown

  8. Tokamak Systems Code

    International Nuclear Information System (INIS)

    Reid, R.L.; Barrett, R.J.; Brown, T.G.

    1985-03-01

    The FEDC Tokamak Systems Code calculates tokamak performance, cost, and configuration as a function of plasma engineering parameters. This version of the code models experimental tokamaks. It does not currently consider tokamak configurations that generate electrical power or incorporate breeding blankets. The code has a modular (or subroutine) structure to allow independent modeling for each major tokamak component or system. A primary benefit of modularization is that a component module may be updated without disturbing the remainder of the systems code as long as the imput to or output from the module remains unchanged

  9. Efficient Coding of Information: Huffman Coding -RE ...

    Indian Academy of Sciences (India)

    to a stream of equally-likely symbols so as to recover the original stream in the event of errors. The for- ... The source-coding problem is one of finding a mapping from U to a ... probability that the random variable X takes the value x written as ...

  10. NR-code: Nonlinear reconstruction code

    Science.gov (United States)

    Yu, Yu; Pen, Ue-Li; Zhu, Hong-Ming

    2018-04-01

    NR-code applies nonlinear reconstruction to the dark matter density field in redshift space and solves for the nonlinear mapping from the initial Lagrangian positions to the final redshift space positions; this reverses the large-scale bulk flows and improves the precision measurement of the baryon acoustic oscillations (BAO) scale.

  11. Synthesizing Certified Code

    Science.gov (United States)

    Whalen, Michael; Schumann, Johann; Fischer, Bernd

    2002-01-01

    Code certification is a lightweight approach to demonstrate software quality on a formal level. Its basic idea is to require producers to provide formal proofs that their code satisfies certain quality properties. These proofs serve as certificates which can be checked independently. Since code certification uses the same underlying technology as program verification, it also requires many detailed annotations (e.g., loop invariants) to make the proofs possible. However, manually adding theses annotations to the code is time-consuming and error-prone. We address this problem by combining code certification with automatic program synthesis. We propose an approach to generate simultaneously, from a high-level specification, code and all annotations required to certify generated code. Here, we describe a certification extension of AUTOBAYES, a synthesis tool which automatically generates complex data analysis programs from compact specifications. AUTOBAYES contains sufficient high-level domain knowledge to generate detailed annotations. This allows us to use a general-purpose verification condition generator to produce a set of proof obligations in first-order logic. The obligations are then discharged using the automated theorem E-SETHEO. We demonstrate our approach by certifying operator safety for a generated iterative data classification program without manual annotation of the code.

  12. Code of Ethics

    Science.gov (United States)

    Division for Early Childhood, Council for Exceptional Children, 2009

    2009-01-01

    The Code of Ethics of the Division for Early Childhood (DEC) of the Council for Exceptional Children is a public statement of principles and practice guidelines supported by the mission of DEC. The foundation of this Code is based on sound ethical reasoning related to professional practice with young children with disabilities and their families…

  13. Interleaved Product LDPC Codes

    OpenAIRE

    Baldi, Marco; Cancellieri, Giovanni; Chiaraluce, Franco

    2011-01-01

    Product LDPC codes take advantage of LDPC decoding algorithms and the high minimum distance of product codes. We propose to add suitable interleavers to improve the waterfall performance of LDPC decoding. Interleaving also reduces the number of low weight codewords, that gives a further advantage in the error floor region.

  14. Insurance billing and coding.

    Science.gov (United States)

    Napier, Rebecca H; Bruelheide, Lori S; Demann, Eric T K; Haug, Richard H

    2008-07-01

    The purpose of this article is to highlight the importance of understanding various numeric and alpha-numeric codes for accurately billing dental and medically related services to private pay or third-party insurance carriers. In the United States, common dental terminology (CDT) codes are most commonly used by dentists to submit claims, whereas current procedural terminology (CPT) and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD.9.CM) codes are more commonly used by physicians to bill for their services. The CPT and ICD.9.CM coding systems complement each other in that CPT codes provide the procedure and service information and ICD.9.CM codes provide the reason or rationale for a particular procedure or service. These codes are more commonly used for "medical necessity" determinations, and general dentists and specialists who routinely perform care, including trauma-related care, biopsies, and dental treatment as a result of or in anticipation of a cancer-related treatment, are likely to use these codes. Claim submissions for care provided can be completed electronically or by means of paper forms.

  15. Error Correcting Codes

    Indian Academy of Sciences (India)

    Science and Automation at ... the Reed-Solomon code contained 223 bytes of data, (a byte ... then you have a data storage system with error correction, that ..... practical codes, storing such a table is infeasible, as it is generally too large.

  16. Scrum Code Camps

    DEFF Research Database (Denmark)

    Pries-Heje, Lene; Pries-Heje, Jan; Dalgaard, Bente

    2013-01-01

    is required. In this paper we present the design of such a new approach, the Scrum Code Camp, which can be used to assess agile team capability in a transparent and consistent way. A design science research approach is used to analyze properties of two instances of the Scrum Code Camp where seven agile teams...

  17. RFQ simulation code

    International Nuclear Information System (INIS)

    Lysenko, W.P.

    1984-04-01

    We have developed the RFQLIB simulation system to provide a means to systematically generate the new versions of radio-frequency quadrupole (RFQ) linac simulation codes that are required by the constantly changing needs of a research environment. This integrated system simplifies keeping track of the various versions of the simulation code and makes it practical to maintain complete and up-to-date documentation. In this scheme, there is a certain standard version of the simulation code that forms a library upon which new versions are built. To generate a new version of the simulation code, the routines to be modified or added are appended to a standard command file, which contains the commands to compile the new routines and link them to the routines in the library. The library itself is rarely changed. Whenever the library is modified, however, this modification is seen by all versions of the simulation code, which actually exist as different versions of the command file. All code is written according to the rules of structured programming. Modularity is enforced by not using COMMON statements, simplifying the relation of the data flow to a hierarchy diagram. Simulation results are similar to those of the PARMTEQ code, as expected, because of the similar physical model. Different capabilities, such as those for generating beams matched in detail to the structure, are available in the new code for help in testing new ideas in designing RFQ linacs

  18. Error Correcting Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 3. Error Correcting Codes - Reed Solomon Codes. Priti Shankar. Series Article Volume 2 Issue 3 March ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India ...

  19. 78 FR 18321 - International Code Council: The Update Process for the International Codes and Standards

    Science.gov (United States)

    2013-03-26

    ... Energy Conservation Code. International Existing Building Code. International Fire Code. International... Code. International Property Maintenance Code. International Residential Code. International Swimming Pool and Spa Code International Wildland-Urban Interface Code. International Zoning Code. ICC Standards...

  20. Predictions of Critical Heat Flux Using the ASSERT-PV Subchannel Code for a CANFLEX Variant Bundle

    International Nuclear Information System (INIS)

    Onder, Ebru Nihan; Leung, Laurence; Kim, Hung; Rao, Yanfei

    2009-01-01

    The ASSERT-PV subchannel code developed by AECL has been applied as a design-assist tool to the advanced CANDU 1 reactor fuel bundle. Based primarily on the CANFLEX 2 fuel bundle, several geometry changes (such as element sizes and pitchcircle diameters of various element rings) were examined to optimize the dryout power and pressure-drop performances of the new fuel bundle. An experiment was performed to obtain dryout power measurements for verification of the ASSERT-PV code predictions. It was carried out using an electrically heated, Refrigerant-134a cooled, fuel bundle string simulator. The axial power profile of the simulator was uniform, while the radial power profile of the element rings was varied simulating profiles in bundles with various fuel compositions and burn-ups. Dryout power measurements are predicted closely using the ASSERT-PV code, particularly at low flows and low pressures, but are overpredicted at high flows and high pressures. The majority of data shows that dryout powers are underpredicted at low inlet-fluid temperatures but overpredicted at high inlet-fluid temperatures

  1. Validation of thermalhydraulic codes

    International Nuclear Information System (INIS)

    Wilkie, D.

    1992-01-01

    Thermalhydraulic codes require to be validated against experimental data collected over a wide range of situations if they are to be relied upon. A good example is provided by the nuclear industry where codes are used for safety studies and for determining operating conditions. Errors in the codes could lead to financial penalties, to the incorrect estimation of the consequences of accidents and even to the accidents themselves. Comparison between prediction and experiment is often described qualitatively or in approximate terms, e.g. ''agreement is within 10%''. A quantitative method is preferable, especially when several competing codes are available. The codes can then be ranked in order of merit. Such a method is described. (Author)

  2. Fracture flow code

    International Nuclear Information System (INIS)

    Dershowitz, W; Herbert, A.; Long, J.

    1989-03-01

    The hydrology of the SCV site will be modelled utilizing discrete fracture flow models. These models are complex, and can not be fully cerified by comparison to analytical solutions. The best approach for verification of these codes is therefore cross-verification between different codes. This is complicated by the variation in assumptions and solution techniques utilized in different codes. Cross-verification procedures are defined which allow comparison of the codes developed by Harwell Laboratory, Lawrence Berkeley Laboratory, and Golder Associates Inc. Six cross-verification datasets are defined for deterministic and stochastic verification of geometric and flow features of the codes. Additional datasets for verification of transport features will be documented in a future report. (13 figs., 7 tabs., 10 refs.) (authors)

  3. Huffman coding in advanced audio coding standard

    Science.gov (United States)

    Brzuchalski, Grzegorz

    2012-05-01

    This article presents several hardware architectures of Advanced Audio Coding (AAC) Huffman noiseless encoder, its optimisations and working implementation. Much attention has been paid to optimise the demand of hardware resources especially memory size. The aim of design was to get as short binary stream as possible in this standard. The Huffman encoder with whole audio-video system has been implemented in FPGA devices.

  4. Report number codes

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.N. (ed.)

    1985-05-01

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

  5. Report number codes

    International Nuclear Information System (INIS)

    Nelson, R.N.

    1985-05-01

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name

  6. Cryptography cracking codes

    CERN Document Server

    2014-01-01

    While cracking a code might seem like something few of us would encounter in our daily lives, it is actually far more prevalent than we may realize. Anyone who has had personal information taken because of a hacked email account can understand the need for cryptography and the importance of encryption-essentially the need to code information to keep it safe. This detailed volume examines the logic and science behind various ciphers, their real world uses, how codes can be broken, and the use of technology in this oft-overlooked field.

  7. Coded Splitting Tree Protocols

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Stefanovic, Cedomir; Popovski, Petar

    2013-01-01

    This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree splitting protocol are initiated, each...... instance is terminated prematurely and subsequently iterated. The combined set of leaves from all the tree instances can then be viewed as a graph code, which is decodable using belief propagation. The main design problem is determining the order of splitting, which enables successful decoding as early...

  8. Transport theory and codes

    International Nuclear Information System (INIS)

    Clancy, B.E.

    1986-01-01

    This chapter begins with a neutron transport equation which includes the one dimensional plane geometry problems, the one dimensional spherical geometry problems, and numerical solutions. The section on the ANISN code and its look-alikes covers problems which can be solved; eigenvalue problems; outer iteration loop; inner iteration loop; and finite difference solution procedures. The input and output data for ANISN is also discussed. Two dimensional problems such as the DOT code are given. Finally, an overview of the Monte-Carlo methods and codes are elaborated on

  9. Gravity inversion code

    International Nuclear Information System (INIS)

    Burkhard, N.R.

    1979-01-01

    The gravity inversion code applies stabilized linear inverse theory to determine the topography of a subsurface density anomaly from Bouguer gravity data. The gravity inversion program consists of four source codes: SEARCH, TREND, INVERT, and AVERAGE. TREND and INVERT are used iteratively to converge on a solution. SEARCH forms the input gravity data files for Nevada Test Site data. AVERAGE performs a covariance analysis on the solution. This document describes the necessary input files and the proper operation of the code. 2 figures, 2 tables

  10. Fulcrum Network Codes

    DEFF Research Database (Denmark)

    2015-01-01

    Fulcrum network codes, which are a network coding framework, achieve three objectives: (i) to reduce the overhead per coded packet to almost 1 bit per source packet; (ii) to operate the network using only low field size operations at intermediate nodes, dramatically reducing complexity...... in the network; and (iii) to deliver an end-to-end performance that is close to that of a high field size network coding system for high-end receivers while simultaneously catering to low-end ones that can only decode in a lower field size. Sources may encode using a high field size expansion to increase...... the number of dimensions seen by the network using a linear mapping. Receivers can tradeoff computational effort with network delay, decoding in the high field size, the low field size, or a combination thereof....

  11. Supervised Convolutional Sparse Coding

    KAUST Repository

    Affara, Lama Ahmed; Ghanem, Bernard; Wonka, Peter

    2018-01-01

    coding, which aims at learning discriminative dictionaries instead of purely reconstructive ones. We incorporate a supervised regularization term into the traditional unsupervised CSC objective to encourage the final dictionary elements

  12. SASSYS LMFBR systems code

    International Nuclear Information System (INIS)

    Dunn, F.E.; Prohammer, F.G.; Weber, D.P.

    1983-01-01

    The SASSYS LMFBR systems analysis code is being developed mainly to analyze the behavior of the shut-down heat-removal system and the consequences of failures in the system, although it is also capable of analyzing a wide range of transients, from mild operational transients through more severe transients leading to sodium boiling in the core and possible melting of clad and fuel. The code includes a detailed SAS4A multi-channel core treatment plus a general thermal-hydraulic treatment of the primary and intermediate heat-transport loops and the steam generators. The code can handle any LMFBR design, loop or pool, with an arbitrary arrangement of components. The code is fast running: usually faster than real time

  13. OCA Code Enforcement

    Data.gov (United States)

    Montgomery County of Maryland — The Office of the County Attorney (OCA) processes Code Violation Citations issued by County agencies. The citations can be viewed by issued department, issued date...

  14. The fast code

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, L.N.; Wilson, R.E. [Oregon State Univ., Dept. of Mechanical Engineering, Corvallis, OR (United States)

    1996-09-01

    The FAST Code which is capable of determining structural loads on a flexible, teetering, horizontal axis wind turbine is described and comparisons of calculated loads with test data are given at two wind speeds for the ESI-80. The FAST Code models a two-bladed HAWT with degrees of freedom for blade bending, teeter, drive train flexibility, yaw, and windwise and crosswind tower motion. The code allows blade dimensions, stiffnesses, and weights to differ and models tower shadow, wind shear, and turbulence. Additionally, dynamic stall is included as are delta-3 and an underslung rotor. Load comparisons are made with ESI-80 test data in the form of power spectral density, rainflow counting, occurrence histograms, and azimuth averaged bin plots. It is concluded that agreement between the FAST Code and test results is good. (au)

  15. Code Disentanglement: Initial Plan

    Energy Technology Data Exchange (ETDEWEB)

    Wohlbier, John Greaton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kelley, Timothy M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rockefeller, Gabriel M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Calef, Matthew Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-27

    The first step to making more ambitious changes in the EAP code base is to disentangle the code into a set of independent, levelized packages. We define a package as a collection of code, most often across a set of files, that provides a defined set of functionality; a package a) can be built and tested as an entity and b) fits within an overall levelization design. Each package contributes one or more libraries, or an application that uses the other libraries. A package set is levelized if the relationships between packages form a directed, acyclic graph and each package uses only packages at lower levels of the diagram (in Fortran this relationship is often describable by the use relationship between modules). Independent packages permit independent- and therefore parallel|development. The packages form separable units for the purposes of development and testing. This is a proven path for enabling finer-grained changes to a complex code.

  16. Induction technology optimization code

    International Nuclear Information System (INIS)

    Caporaso, G.J.; Brooks, A.L.; Kirbie, H.C.

    1992-01-01

    A code has been developed to evaluate relative costs of induction accelerator driver systems for relativistic klystrons. The code incorporates beam generation, transport and pulsed power system constraints to provide an integrated design tool. The code generates an injector/accelerator combination which satisfies the top level requirements and all system constraints once a small number of design choices have been specified (rise time of the injector voltage and aspect ratio of the ferrite induction cores, for example). The code calculates dimensions of accelerator mechanical assemblies and values of all electrical components. Cost factors for machined parts, raw materials and components are applied to yield a total system cost. These costs are then plotted as a function of the two design choices to enable selection of an optimum design based on various criteria. (Author) 11 refs., 3 figs

  17. VT ZIP Code Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) A ZIP Code Tabulation Area (ZCTA) is a statistical geographic entity that approximates the delivery area for a U.S. Postal Service five-digit...

  18. Bandwidth efficient coding

    CERN Document Server

    Anderson, John B

    2017-01-01

    Bandwidth Efficient Coding addresses the major challenge in communication engineering today: how to communicate more bits of information in the same radio spectrum. Energy and bandwidth are needed to transmit bits, and bandwidth affects capacity the most. Methods have been developed that are ten times as energy efficient at a given bandwidth consumption as simple methods. These employ signals with very complex patterns and are called "coding" solutions. The book begins with classical theory before introducing new techniques that combine older methods of error correction coding and radio transmission in order to create narrowband methods that are as efficient in both spectrum and energy as nature allows. Other topics covered include modulation techniques such as CPM, coded QAM and pulse design.

  19. Reactor lattice codes

    International Nuclear Information System (INIS)

    Kulikowska, T.

    2001-01-01

    The description of reactor lattice codes is carried out on the example of the WIMSD-5B code. The WIMS code in its various version is the most recognised lattice code. It is used in all parts of the world for calculations of research and power reactors. The version WIMSD-5B is distributed free of charge by NEA Data Bank. The description of its main features given in the present lecture follows the aspects defined previously for lattice calculations in the lecture on Reactor Lattice Transport Calculations. The spatial models are described, and the approach to the energy treatment is given. Finally the specific algorithm applied in fuel depletion calculations is outlined. (author)

  20. Critical Care Coding for Neurologists.

    Science.gov (United States)

    Nuwer, Marc R; Vespa, Paul M

    2015-10-01

    Accurate coding is an important function of neurologic practice. This contribution to Continuum is part of an ongoing series that presents helpful coding information along with examples related to the issue topic. Tips for diagnosis coding, Evaluation and Management coding, procedure coding, or a combination are presented, depending on which is most applicable to the subject area of the issue.

  1. Lattice Index Coding

    OpenAIRE

    Natarajan, Lakshmi; Hong, Yi; Viterbo, Emanuele

    2014-01-01

    The index coding problem involves a sender with K messages to be transmitted across a broadcast channel, and a set of receivers each of which demands a subset of the K messages while having prior knowledge of a different subset as side information. We consider the specific case of noisy index coding where the broadcast channel is Gaussian and every receiver demands all the messages from the source. Instances of this communication problem arise in wireless relay networks, sensor networks, and ...

  2. Towards advanced code simulators

    International Nuclear Information System (INIS)

    Scriven, A.H.

    1990-01-01

    The Central Electricity Generating Board (CEGB) uses advanced thermohydraulic codes extensively to support PWR safety analyses. A system has been developed to allow fully interactive execution of any code with graphical simulation of the operator desk and mimic display. The system operates in a virtual machine environment, with the thermohydraulic code executing in one virtual machine, communicating via interrupts with any number of other virtual machines each running other programs and graphics drivers. The driver code itself does not have to be modified from its normal batch form. Shortly following the release of RELAP5 MOD1 in IBM compatible form in 1983, this code was used as the driver for this system. When RELAP5 MOD2 became available, it was adopted with no changes needed in the basic system. Overall the system has been used for some 5 years for the analysis of LOBI tests, full scale plant studies and for simple what-if studies. For gaining rapid understanding of system dependencies it has proved invaluable. The graphical mimic system, being independent of the driver code, has also been used with other codes to study core rewetting, to replay results obtained from batch jobs on a CRAY2 computer system and to display suitably processed experimental results from the LOBI facility to aid interpretation. For the above work real-time execution was not necessary. Current work now centers on implementing the RELAP 5 code on a true parallel architecture machine. Marconi Simulation have been contracted to investigate the feasibility of using upwards of 100 processors, each capable of a peak of 30 MIPS to run a highly detailed RELAP5 model in real time, complete with specially written 3D core neutronics and balance of plant models. This paper describes the experience of using RELAP5 as an analyzer/simulator, and outlines the proposed methods and problems associated with parallel execution of RELAP5

  3. Cracking the Gender Codes

    DEFF Research Database (Denmark)

    Rennison, Betina Wolfgang

    2016-01-01

    extensive work to raise the proportion of women. This has helped slightly, but women remain underrepresented at the corporate top. Why is this so? What can be done to solve it? This article presents five different types of answers relating to five discursive codes: nature, talent, business, exclusion...... in leadership management, we must become more aware and take advantage of this complexity. We must crack the codes in order to crack the curve....

  4. KENO-V code

    International Nuclear Information System (INIS)

    Cramer, S.N.

    1984-01-01

    The KENO-V code is the current release of the Oak Ridge multigroup Monte Carlo criticality code development. The original KENO, with 16 group Hansen-Roach cross sections and P 1 scattering, was one ot the first multigroup Monte Carlo codes and it and its successors have always been a much-used research tool for criticality studies. KENO-V is able to accept large neutron cross section libraries (a 218 group set is distributed with the code) and has a general P/sub N/ scattering capability. A supergroup feature allows execution of large problems on small computers, but at the expense of increased calculation time and system input/output operations. This supergroup feature is activated automatically by the code in a manner which utilizes as much computer memory as is available. The primary purpose of KENO-V is to calculate the system k/sub eff/, from small bare critical assemblies to large reflected arrays of differing fissile and moderator elements. In this respect KENO-V neither has nor requires the many options and sophisticated biasing techniques of general Monte Carlo codes

  5. Code, standard and specifications

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    Radiography also same as the other technique, it need standard. This standard was used widely and method of used it also regular. With that, radiography testing only practical based on regulations as mentioned and documented. These regulation or guideline documented in code, standard and specifications. In Malaysia, level one and basic radiographer can do radiography work based on instruction give by level two or three radiographer. This instruction was produced based on guideline that mention in document. Level two must follow the specifications mentioned in standard when write the instruction. From this scenario, it makes clearly that this radiography work is a type of work that everything must follow the rule. For the code, the radiography follow the code of American Society for Mechanical Engineer (ASME) and the only code that have in Malaysia for this time is rule that published by Atomic Energy Licensing Board (AELB) known as Practical code for radiation Protection in Industrial radiography. With the existence of this code, all the radiography must follow the rule or standard regulated automatically.

  6. Fast Coding Unit Encoding Mechanism for Low Complexity Video Coding

    OpenAIRE

    Gao, Yuan; Liu, Pengyu; Wu, Yueying; Jia, Kebin; Gao, Guandong

    2016-01-01

    In high efficiency video coding (HEVC), coding tree contributes to excellent compression performance. However, coding tree brings extremely high computational complexity. Innovative works for improving coding tree to further reduce encoding time are stated in this paper. A novel low complexity coding tree mechanism is proposed for HEVC fast coding unit (CU) encoding. Firstly, this paper makes an in-depth study of the relationship among CU distribution, quantization parameter (QP) and content ...

  7. A benchmark comparison of the Canadian Supercritical Water-Cooled Reactor (SCWR) 64-element fuel lattice cell parameters using various computer codes

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, J.; Salaun, F.; Hummel, D.; Moghrabi, A., E-mail: sharpejr@mcmaster.ca [McMaster University, Hamilton, ON (Canada); Nowak, M. [McMaster University, Hamilton, ON (Canada); Institut National Polytechnique de Grenoble, Phelma, Grenoble (France); Pencer, J. [McMaster University, Hamilton, ON (Canada); Canadian Nuclear Laboratories, Chalk River, ON, (Canada); Novog, D.; Buijs, A. [McMaster University, Hamilton, ON (Canada)

    2015-07-01

    Discrepancies in key lattice physics parameters have been observed between various deterministic (e.g. DRAGON and WIMS-AECL) and stochastic (MCNP, KENO) neutron transport codes in modeling previous versions of the Canadian SCWR lattice cell. Further, inconsistencies in these parameters have also been observed when using different nuclear data libraries. In this work, the predictions of k∞, various reactivity coefficients, and relative ring-averaged pin powers have been re-evaluated using these codes and libraries with the most recent 64-element fuel assembly geometry. A benchmark problem has been defined to quantify the dissimilarities between code results for a number of responses along the fuel channel under prescribed hot full power (HFP), hot zero power (HZP) and cold zero power (CZP) conditions and at several fuel burnups (0, 25 and 50 MW·d·kg{sup -1} [HM]). Results from deterministic (TRITON, DRAGON) and stochastic codes (MCNP6, KENO V.a and KENO-VI) are presented. (author)

  8. Materials research in AECL, Spring 1970

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1970-05-15

    This report gives a summary of materials research at Atomic Energy of Canada Limited. The topics covered in this report include engineering design with brittle materials, texture and mechanical properties of zirconium alloy tubing, structural damage by ion bombardment, research on silicon carbide, shallow phosphorus diffusion in p-type silicon and scanning electron microscopy. CRNL facilities for the examination of irradiated materials is also discussed.

  9. AECL research programs in life sciences

    International Nuclear Information System (INIS)

    Marko, A.M.

    1981-04-01

    The present report summarizes the current research activities in life sciences in the Atomic Energy of Canada Limited-Research Company. The research is carried out at its two main research sites: the Chalk River Nuclear Laboratories and the Whiteshell Nuclear Research Establishment. The summaries cover the following areas of research: radiation biology, medical biophysics, epidemiology, environmental research and dosimetry. (author)

  10. AECL's excavation stability study - summary of observations

    International Nuclear Information System (INIS)

    Read, R.S.; Chandler, N.A.

    1996-05-01

    The Excavation Stability Study (ESS) was conducted at the 420 Level of the Underground Research Laboratory (URL) to evaluate stability and the extent of excavation damage in tunnels as a function of tunnel geometry and orientation, geology, and excavation method. A series of ovaloid and circular openings were used to achieve different boundary stress levels and near-field stress distributions to assess the effect of tunnel geometry on damage development. Several of these openings had sections in both granite and granodiorite lithology, providing a comparison of damage in rock types with different strength characteristics. Damage around circular tunnels (one excavated by drill-and-blast, the other by mechanical means) was also investigated. The study.showed that mechanically stable openings can be excavated in the most adverse stress conditions at the 420 Level of the URL. In addition, it was shown that tunnel stability is sensitive to tunnel shape, variations in geology, and to some extent, the excavation method. Findings of the study are relevant in developing design criteria, and in assessing the feasibility of constructing large ovaloid openings in adverse stress conditions. This report summarizes the preliminary observations related to tunnel stability and excavation damage. (author). 8 refs., 7 tabs., 23 figs

  11. The AECL research and development program

    International Nuclear Information System (INIS)

    Hart, R.G.; Woods, A.D.B.

    1980-02-01

    The research and development program of the Atomic Energy of Canada Research Company is briefly described. Goals and objectives are emphasized, some recent highlights are given and the importance of technology transfer is discussed. A short representative bibliography is included. (auth)

  12. Materials research in AECL, Spring 1970

    International Nuclear Information System (INIS)

    1970-05-01

    This report gives a summary of materials research at Atomic Energy of Canada Limited. The topics covered in this report include engineering design with brittle materials, texture and mechanical properties of zirconium alloy tubing, structural damage by ion bombardment, research on silicon carbide, shallow phosphorus diffusion in p-type silicon and scanning electron microscopy. CRNL facilities for the examination of irradiated materials is also discussed

  13. AECL programs in basic physics research

    International Nuclear Information System (INIS)

    Bartholomew, G.A.; Dolling, G.; Harvey, M.; Milton, J.C.D.

    1982-02-01

    This report describes the CRNL program of research into the basic properties of atomic nuclei and condensed matter (liquids and solids). Brief descriptions are given of some of the current experimental programs done principally at the NRU reactor and MP tandem accelerator, the associated theoretical studies, and some highlights of past achievements

  14. AECL research programs in systems chemistry

    International Nuclear Information System (INIS)

    Lister, D.H.; Pathania, R.S.

    1984-05-01

    Research programs in Systems Chemistry are aimed at preserving the integrity of the many working systems in CANDU reactors and at minimizing chemistry-induced problems such as radiation field growth or fouling of surfaces. The topics of main concern are the chemistry and corrosion of steam generators, for it is in this general area that the potential for serious problems is very real

  15. SPECTRAL AMPLITUDE CODING OCDMA SYSTEMS USING ENHANCED DOUBLE WEIGHT CODE

    Directory of Open Access Journals (Sweden)

    F.N. HASOON

    2006-12-01

    Full Text Available A new code structure for spectral amplitude coding optical code division multiple access systems based on double weight (DW code families is proposed. The DW has a fixed weight of two. Enhanced double-weight (EDW code is another variation of a DW code family that can has a variable weight greater than one. The EDW code possesses ideal cross-correlation properties and exists for every natural number n. A much better performance can be provided by using the EDW code compared to the existing code such as Hadamard and Modified Frequency-Hopping (MFH codes. It has been observed that theoretical analysis and simulation for EDW is much better performance compared to Hadamard and Modified Frequency-Hopping (MFH codes.

  16. Nuclear code abstracts (1975 edition)

    International Nuclear Information System (INIS)

    Akanuma, Makoto; Hirakawa, Takashi

    1976-02-01

    Nuclear Code Abstracts is compiled in the Nuclear Code Committee to exchange information of the nuclear code developments among members of the committee. Enlarging the collection, the present one includes nuclear code abstracts obtained in 1975 through liaison officers of the organizations in Japan participating in the Nuclear Energy Agency's Computer Program Library at Ispra, Italy. The classification of nuclear codes and the format of code abstracts are the same as those in the library. (auth.)

  17. Some new ternary linear codes

    Directory of Open Access Journals (Sweden)

    Rumen Daskalov

    2017-07-01

    Full Text Available Let an $[n,k,d]_q$ code be a linear code of length $n$, dimension $k$ and minimum Hamming distance $d$ over $GF(q$. One of the most important problems in coding theory is to construct codes with optimal minimum distances. In this paper 22 new ternary linear codes are presented. Two of them are optimal. All new codes improve the respective lower bounds in [11].

  18. ACE - Manufacturer Identification Code (MID)

    Data.gov (United States)

    Department of Homeland Security — The ACE Manufacturer Identification Code (MID) application is used to track and control identifications codes for manufacturers. A manufacturer is identified on an...

  19. Algebraic and stochastic coding theory

    CERN Document Server

    Kythe, Dave K

    2012-01-01

    Using a simple yet rigorous approach, Algebraic and Stochastic Coding Theory makes the subject of coding theory easy to understand for readers with a thorough knowledge of digital arithmetic, Boolean and modern algebra, and probability theory. It explains the underlying principles of coding theory and offers a clear, detailed description of each code. More advanced readers will appreciate its coverage of recent developments in coding theory and stochastic processes. After a brief review of coding history and Boolean algebra, the book introduces linear codes, including Hamming and Golay codes.

  20. Optical coding theory with Prime

    CERN Document Server

    Kwong, Wing C

    2013-01-01

    Although several books cover the coding theory of wireless communications and the hardware technologies and coding techniques of optical CDMA, no book has been specifically dedicated to optical coding theory-until now. Written by renowned authorities in the field, Optical Coding Theory with Prime gathers together in one volume the fundamentals and developments of optical coding theory, with a focus on families of prime codes, supplemented with several families of non-prime codes. The book also explores potential applications to coding-based optical systems and networks. Learn How to Construct

  1. The Aster code

    International Nuclear Information System (INIS)

    Delbecq, J.M.

    1999-01-01

    The Aster code is a 2D or 3D finite-element calculation code for structures developed by the R and D direction of Electricite de France (EdF). This dossier presents a complete overview of the characteristics and uses of the Aster code: introduction of version 4; the context of Aster (organisation of the code development, versions, systems and interfaces, development tools, quality assurance, independent validation); static mechanics (linear thermo-elasticity, Euler buckling, cables, Zarka-Casier method); non-linear mechanics (materials behaviour, big deformations, specific loads, unloading and loss of load proportionality indicators, global algorithm, contact and friction); rupture mechanics (G energy restitution level, restitution level in thermo-elasto-plasticity, 3D local energy restitution level, KI and KII stress intensity factors, calculation of limit loads for structures), specific treatments (fatigue, rupture, wear, error estimation); meshes and models (mesh generation, modeling, loads and boundary conditions, links between different modeling processes, resolution of linear systems, display of results etc..); vibration mechanics (modal and harmonic analysis, dynamics with shocks, direct transient dynamics, seismic analysis and aleatory dynamics, non-linear dynamics, dynamical sub-structuring); fluid-structure interactions (internal acoustics, mass, rigidity and damping); linear and non-linear thermal analysis; steels and metal industry (structure transformations); coupled problems (internal chaining, internal thermo-hydro-mechanical coupling, chaining with other codes); products and services. (J.S.)

  2. Adaptive distributed source coding.

    Science.gov (United States)

    Varodayan, David; Lin, Yao-Chung; Girod, Bernd

    2012-05-01

    We consider distributed source coding in the presence of hidden variables that parameterize the statistical dependence among sources. We derive the Slepian-Wolf bound and devise coding algorithms for a block-candidate model of this problem. The encoder sends, in addition to syndrome bits, a portion of the source to the decoder uncoded as doping bits. The decoder uses the sum-product algorithm to simultaneously recover the source symbols and the hidden statistical dependence variables. We also develop novel techniques based on density evolution (DE) to analyze the coding algorithms. We experimentally confirm that our DE analysis closely approximates practical performance. This result allows us to efficiently optimize parameters of the algorithms. In particular, we show that the system performs close to the Slepian-Wolf bound when an appropriate doping rate is selected. We then apply our coding and analysis techniques to a reduced-reference video quality monitoring system and show a bit rate saving of about 75% compared with fixed-length coding.

  3. Speech coding code- excited linear prediction

    CERN Document Server

    Bäckström, Tom

    2017-01-01

    This book provides scientific understanding of the most central techniques used in speech coding both for advanced students as well as professionals with a background in speech audio and or digital signal processing. It provides a clear connection between the whys hows and whats thus enabling a clear view of the necessity purpose and solutions provided by various tools as well as their strengths and weaknesses in each respect Equivalently this book sheds light on the following perspectives for each technology presented Objective What do we want to achieve and especially why is this goal important Resource Information What information is available and how can it be useful and Resource Platform What kind of platforms are we working with and what are their capabilities restrictions This includes computational memory and acoustic properties and the transmission capacity of devices used. The book goes on to address Solutions Which solutions have been proposed and how can they be used to reach the stated goals and ...

  4. Spatially coded backscatter radiography

    International Nuclear Information System (INIS)

    Thangavelu, S.; Hussein, E.M.A.

    2007-01-01

    Conventional radiography requires access to two opposite sides of an object, which makes it unsuitable for the inspection of extended and/or thick structures (airframes, bridges, floors etc.). Backscatter imaging can overcome this problem, but the indications obtained are difficult to interpret. This paper applies the coded aperture technique to gamma-ray backscatter-radiography in order to enhance the detectability of flaws. This spatial coding method involves the positioning of a mask with closed and open holes to selectively permit or block the passage of radiation. The obtained coded-aperture indications are then mathematically decoded to detect the presence of anomalies. Indications obtained from Monte Carlo calculations were utilized in this work to simulate radiation scattering measurements. These simulated measurements were used to investigate the applicability of this technique to the detection of flaws by backscatter radiography

  5. Aztheca Code; Codigo Aztheca

    Energy Technology Data Exchange (ETDEWEB)

    Quezada G, S.; Espinosa P, G. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Ciudad de Mexico (Mexico); Centeno P, J.; Sanchez M, H., E-mail: sequga@gmail.com [UNAM, Facultad de Ingenieria, Ciudad Universitaria, Circuito Exterior s/n, 04510 Ciudad de Mexico (Mexico)

    2017-09-15

    This paper presents the Aztheca code, which is formed by the mathematical models of neutron kinetics, power generation, heat transfer, core thermo-hydraulics, recirculation systems, dynamic pressure and level models and control system. The Aztheca code is validated with plant data, as well as with predictions from the manufacturer when the reactor operates in a stationary state. On the other hand, to demonstrate that the model is applicable during a transient, an event occurred in a nuclear power plant with a BWR reactor is selected. The plant data are compared with the results obtained with RELAP-5 and the Aztheca model. The results show that both RELAP-5 and the Aztheca code have the ability to adequately predict the behavior of the reactor. (Author)

  6. The Coding Question.

    Science.gov (United States)

    Gallistel, C R

    2017-07-01

    Recent electrophysiological results imply that the duration of the stimulus onset asynchrony in eyeblink conditioning is encoded by a mechanism intrinsic to the cerebellar Purkinje cell. This raises the general question - how is quantitative information (durations, distances, rates, probabilities, amounts, etc.) transmitted by spike trains and encoded into engrams? The usual assumption is that information is transmitted by firing rates. However, rate codes are energetically inefficient and computationally awkward. A combinatorial code is more plausible. If the engram consists of altered synaptic conductances (the usual assumption), then we must ask how numbers may be written to synapses. It is much easier to formulate a coding hypothesis if the engram is realized by a cell-intrinsic molecular mechanism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Revised SRAC code system

    International Nuclear Information System (INIS)

    Tsuchihashi, Keichiro; Ishiguro, Yukio; Kaneko, Kunio; Ido, Masaru.

    1986-09-01

    Since the publication of JAERI-1285 in 1983 for the preliminary version of the SRAC code system, a number of additions and modifications to the functions have been made to establish an overall neutronics code system. Major points are (1) addition of JENDL-2 version of data library, (2) a direct treatment of doubly heterogeneous effect on resonance absorption, (3) a generalized Dancoff factor, (4) a cell calculation based on the fixed boundary source problem, (5) the corresponding edit required for experimental analysis and reactor design, (6) a perturbation theory calculation for reactivity change, (7) an auxiliary code for core burnup and fuel management, etc. This report is a revision of the users manual which consists of the general description, input data requirements and their explanation, detailed information on usage, mathematics, contents of libraries and sample I/O. (author)

  8. Code query by example

    Science.gov (United States)

    Vaucouleur, Sebastien

    2011-02-01

    We introduce code query by example for customisation of evolvable software products in general and of enterprise resource planning systems (ERPs) in particular. The concept is based on an initial empirical study on practices around ERP systems. We motivate our design choices based on those empirical results, and we show how the proposed solution helps with respect to the infamous upgrade problem: the conflict between the need for customisation and the need for upgrade of ERP systems. We further show how code query by example can be used as a form of lightweight static analysis, to detect automatically potential defects in large software products. Code query by example as a form of lightweight static analysis is particularly interesting in the context of ERP systems: it is often the case that programmers working in this field are not computer science specialists but more of domain experts. Hence, they require a simple language to express custom rules.

  9. The correspondence between projective codes and 2-weight codes

    NARCIS (Netherlands)

    Brouwer, A.E.; Eupen, van M.J.M.; Tilborg, van H.C.A.; Willems, F.M.J.

    1994-01-01

    The hyperplanes intersecting a 2-weight code in the same number of points obviously form the point set of a projective code. On the other hand, if we have a projective code C, then we can make a 2-weight code by taking the multiset of points E PC with multiplicity "Y(w), where W is the weight of

  10. Visualizing code and coverage changes for code review

    NARCIS (Netherlands)

    Oosterwaal, Sebastiaan; van Deursen, A.; De Souza Coelho, R.; Sawant, A.A.; Bacchelli, A.

    2016-01-01

    One of the tasks of reviewers is to verify that code modifications are well tested. However, current tools offer little support in understanding precisely how changes to the code relate to changes to the tests. In particular, it is hard to see whether (modified) test code covers the changed code.

  11. Turbo-Gallager Codes: The Emergence of an Intelligent Coding ...

    African Journals Online (AJOL)

    Today, both turbo codes and low-density parity-check codes are largely superior to other code families and are being used in an increasing number of modern communication systems including 3G standards, satellite and deep space communications. However, the two codes have certain distinctive characteristics that ...

  12. Code of Medical Ethics

    Directory of Open Access Journals (Sweden)

    . SZD-SZZ

    2017-03-01

    Full Text Available Te Code was approved on December 12, 1992, at the 3rd regular meeting of the General Assembly of the Medical Chamber of Slovenia and revised on April 24, 1997, at the 27th regular meeting of the General Assembly of the Medical Chamber of Slovenia. The Code was updated and harmonized with the Medical Association of Slovenia and approved on October 6, 2016, at the regular meeting of the General Assembly of the Medical Chamber of Slovenia.

  13. Supervised Convolutional Sparse Coding

    KAUST Repository

    Affara, Lama Ahmed

    2018-04-08

    Convolutional Sparse Coding (CSC) is a well-established image representation model especially suited for image restoration tasks. In this work, we extend the applicability of this model by proposing a supervised approach to convolutional sparse coding, which aims at learning discriminative dictionaries instead of purely reconstructive ones. We incorporate a supervised regularization term into the traditional unsupervised CSC objective to encourage the final dictionary elements to be discriminative. Experimental results show that using supervised convolutional learning results in two key advantages. First, we learn more semantically relevant filters in the dictionary and second, we achieve improved image reconstruction on unseen data.

  14. CONCEPT computer code

    International Nuclear Information System (INIS)

    Delene, J.

    1984-01-01

    CONCEPT is a computer code that will provide conceptual capital investment cost estimates for nuclear and coal-fired power plants. The code can develop an estimate for construction at any point in time. Any unit size within the range of about 400 to 1300 MW electric may be selected. Any of 23 reference site locations across the United States and Canada may be selected. PWR, BWR, and coal-fired plants burning high-sulfur and low-sulfur coal can be estimated. Multiple-unit plants can be estimated. Costs due to escalation/inflation and interest during construction are calculated

  15. Principles of speech coding

    CERN Document Server

    Ogunfunmi, Tokunbo

    2010-01-01

    It is becoming increasingly apparent that all forms of communication-including voice-will be transmitted through packet-switched networks based on the Internet Protocol (IP). Therefore, the design of modern devices that rely on speech interfaces, such as cell phones and PDAs, requires a complete and up-to-date understanding of the basics of speech coding. Outlines key signal processing algorithms used to mitigate impairments to speech quality in VoIP networksOffering a detailed yet easily accessible introduction to the field, Principles of Speech Coding provides an in-depth examination of the

  16. Evaluation Codes from an Affine Veriety Code Perspective

    DEFF Research Database (Denmark)

    Geil, Hans Olav

    2008-01-01

    Evaluation codes (also called order domain codes) are traditionally introduced as generalized one-point geometric Goppa codes. In the present paper we will give a new point of view on evaluation codes by introducing them instead as particular nice examples of affine variety codes. Our study...... includes a reformulation of the usual methods to estimate the minimum distances of evaluation codes into the setting of affine variety codes. Finally we describe the connection to the theory of one-pointgeometric Goppa codes. Contents 4.1 Introduction...... . . . . . . . . . . . . . . . . . . . . . . . 171 4.9 Codes form order domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 4.10 One-point geometric Goppa codes . . . . . . . . . . . . . . . . . . . . . . . . 176 4.11 Bibliographical Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 References...

  17. Dual Coding in Children.

    Science.gov (United States)

    Burton, John K.; Wildman, Terry M.

    The purpose of this study was to test the applicability of the dual coding hypothesis to children's recall performance. The hypothesis predicts that visual interference will have a small effect on the recall of visually presented words or pictures, but that acoustic interference will cause a decline in recall of visually presented words and…

  18. Physical layer network coding

    DEFF Research Database (Denmark)

    Fukui, Hironori; Popovski, Petar; Yomo, Hiroyuki

    2014-01-01

    Physical layer network coding (PLNC) has been proposed to improve throughput of the two-way relay channel, where two nodes communicate with each other, being assisted by a relay node. Most of the works related to PLNC are focused on a simple three-node model and they do not take into account...

  19. Radioactive action code

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    A new coding system, 'Hazrad', for buildings and transportation containers for alerting emergency services personnel to the presence of radioactive materials has been developed in the United Kingdom. The hazards of materials in the buildings or transport container, together with the recommended emergency action, are represented by a number of codes which are marked on the building or container and interpreted from a chart carried as a pocket-size guide. Buildings would be marked with the familiar yellow 'radioactive' trefoil, the written information 'Radioactive materials' and a list of isotopes. Under this the 'Hazrad' code would be written - three symbols to denote the relative radioactive risk (low, medium or high), the biological risk (also low, medium or high) and the third showing the type of radiation emitted, alpha, beta or gamma. The response cards indicate appropriate measures to take, eg for a high biological risk, Bio3, the wearing of a gas-tight protection suit is advised. The code and its uses are explained. (U.K.)

  20. Building Codes and Regulations.

    Science.gov (United States)

    Fisher, John L.

    The hazard of fire is of great concern to libraries due to combustible books and new plastics used in construction and interiors. Building codes and standards can offer architects and planners guidelines to follow but these standards should be closely monitored, updated, and researched for fire prevention. (DS)

  1. Physics of codes

    International Nuclear Information System (INIS)

    Cooper, R.K.; Jones, M.E.

    1989-01-01

    The title given this paper is a bit presumptuous, since one can hardly expect to cover the physics incorporated into all the codes already written and currently being written. The authors focus on those codes which have been found to be particularly useful in the analysis and design of linacs. At that the authors will be a bit parochial and discuss primarily those codes used for the design of radio-frequency (rf) linacs, although the discussions of TRANSPORT and MARYLIE have little to do with the time structures of the beams being analyzed. The plan of this paper is first to describe rather simply the concepts of emittance and brightness, then to describe rather briefly each of the codes TRANSPORT, PARMTEQ, TBCI, MARYLIE, and ISIS, indicating what physics is and is not included in each of them. It is expected that the vast majority of what is covered will apply equally well to protons and electrons (and other particles). This material is intended to be tutorial in nature and can in no way be expected to be exhaustive. 31 references, 4 figures

  2. Reliability and code level

    NARCIS (Netherlands)

    Kasperski, M.; Geurts, C.P.W.

    2005-01-01

    The paper describes the work of the IAWE Working Group WBG - Reliability and Code Level, one of the International Codification Working Groups set up at ICWE10 in Copenhagen. The following topics are covered: sources of uncertainties in the design wind load, appropriate design target values for the

  3. Ready, steady… Code!

    CERN Multimedia

    Anaïs Schaeffer

    2013-01-01

    This summer, CERN took part in the Google Summer of Code programme for the third year in succession. Open to students from all over the world, this programme leads to very successful collaborations for open source software projects.   Image: GSoC 2013. Google Summer of Code (GSoC) is a global programme that offers student developers grants to write code for open-source software projects. Since its creation in 2005, the programme has brought together some 6,000 students from over 100 countries worldwide. The students selected by Google are paired with a mentor from one of the participating projects, which can be led by institutes, organisations, companies, etc. This year, CERN PH Department’s SFT (Software Development for Experiments) Group took part in the GSoC programme for the third time, submitting 15 open-source projects. “Once published on the Google Summer for Code website (in April), the projects are open to applications,” says Jakob Blomer, one of the o...

  4. CERN Code of Conduct

    CERN Document Server

    Department, HR

    2010-01-01

    The Code is intended as a guide in helping us, as CERN contributors, to understand how to conduct ourselves, treat others and expect to be treated. It is based around the five core values of the Organization. We should all become familiar with it and try to incorporate it into our daily life at CERN.

  5. Nuclear safety code study

    Energy Technology Data Exchange (ETDEWEB)

    Hu, H.H.; Ford, D.; Le, H.; Park, S.; Cooke, K.L.; Bleakney, T.; Spanier, J.; Wilburn, N.P.; O' Reilly, B.; Carmichael, B.

    1981-01-01

    The objective is to analyze an overpower accident in an LMFBR. A simplified model of the primary coolant loop was developed in order to understand the instabilities encountered with the MELT III and SAS codes. The computer programs were translated for switching to the IBM 4331. Numerical methods were investigated for solving the neutron kinetics equations; the Adams and Gear methods were compared. (DLC)

  6. Revised C++ coding conventions

    CERN Document Server

    Callot, O

    2001-01-01

    This document replaces the note LHCb 98-049 by Pavel Binko. After a few years of practice, some simplification and clarification of the rules was needed. As many more people have now some experience in writing C++ code, their opinion was also taken into account to get a commonly agreed set of conventions

  7. Corporate governance through codes

    NARCIS (Netherlands)

    Haxhi, I.; Aguilera, R.V.; Vodosek, M.; den Hartog, D.; McNett, J.M.

    2014-01-01

    The UK's 1992 Cadbury Report defines corporate governance (CG) as the system by which businesses are directed and controlled. CG codes are a set of best practices designed to address deficiencies in the formal contracts and institutions by suggesting prescriptions on the preferred role and

  8. Error Correcting Codes -34 ...

    Indian Academy of Sciences (India)

    information and coding theory. A large scale relay computer had failed to deliver the expected results due to a hardware fault. Hamming, one of the active proponents of computer usage, was determined to find an efficient means by which computers could detect and correct their own faults. A mathematician by train-.

  9. Broadcast Coded Slotted ALOHA

    DEFF Research Database (Denmark)

    Ivanov, Mikhail; Brännström, Frederik; Graell i Amat, Alexandre

    2016-01-01

    We propose an uncoordinated medium access control (MAC) protocol, called all-to-all broadcast coded slotted ALOHA (B-CSA) for reliable all-to-all broadcast with strict latency constraints. In B-CSA, each user acts as both transmitter and receiver in a half-duplex mode. The half-duplex mode gives ...

  10. Software Defined Coded Networking

    DEFF Research Database (Denmark)

    Di Paola, Carla; Roetter, Daniel Enrique Lucani; Palazzo, Sergio

    2017-01-01

    the quality of each link and even across neighbouring links and using simulations to show that an additional reduction of packet transmission in the order of 40% is possible. Second, to advocate for the use of network coding (NC) jointly with software defined networking (SDN) providing an implementation...

  11. New code of conduct

    CERN Multimedia

    Laëtitia Pedroso

    2010-01-01

    During his talk to the staff at the beginning of the year, the Director-General mentioned that a new code of conduct was being drawn up. What exactly is it and what is its purpose? Anne-Sylvie Catherin, Head of the Human Resources (HR) Department, talked to us about the whys and wherefores of the project.   Drawing by Georges Boixader from the cartoon strip “The World of Particles” by Brian Southworth. A code of conduct is a general framework laying down the behaviour expected of all members of an organisation's personnel. “CERN is one of the very few international organisations that don’t yet have one", explains Anne-Sylvie Catherin. “We have been thinking about introducing a code of conduct for a long time but lacked the necessary resources until now”. The call for a code of conduct has come from different sources within the Laboratory. “The Equal Opportunities Advisory Panel (read also the "Equal opportuni...

  12. (Almost) practical tree codes

    KAUST Repository

    Khina, Anatoly

    2016-08-15

    We consider the problem of stabilizing an unstable plant driven by bounded noise over a digital noisy communication link, a scenario at the heart of networked control. To stabilize such a plant, one needs real-time encoding and decoding with an error probability profile that decays exponentially with the decoding delay. The works of Schulman and Sahai over the past two decades have developed the notions of tree codes and anytime capacity, and provided the theoretical framework for studying such problems. Nonetheless, there has been little practical progress in this area due to the absence of explicit constructions of tree codes with efficient encoding and decoding algorithms. Recently, linear time-invariant tree codes were proposed to achieve the desired result under maximum-likelihood decoding. In this work, we take one more step towards practicality, by showing that these codes can be efficiently decoded using sequential decoding algorithms, up to some loss in performance (and with some practical complexity caveats). We supplement our theoretical results with numerical simulations that demonstrate the effectiveness of the decoder in a control system setting.

  13. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    having a probability Pi of being equal to a 1. Let us assume ... equal to a 0/1 has no bearing on the probability of the. It is often ... bits (call this set S) whose individual bits add up to zero ... In the context of binary error-correct~ng codes, specifi-.

  14. The Redox Code.

    Science.gov (United States)

    Jones, Dean P; Sies, Helmut

    2015-09-20

    The redox code is a set of principles that defines the positioning of the nicotinamide adenine dinucleotide (NAD, NADP) and thiol/disulfide and other redox systems as well as the thiol redox proteome in space and time in biological systems. The code is richly elaborated in an oxygen-dependent life, where activation/deactivation cycles involving O₂ and H₂O₂ contribute to spatiotemporal organization for differentiation, development, and adaptation to the environment. Disruption of this organizational structure during oxidative stress represents a fundamental mechanism in system failure and disease. Methodology in assessing components of the redox code under physiological conditions has progressed, permitting insight into spatiotemporal organization and allowing for identification of redox partners in redox proteomics and redox metabolomics. Complexity of redox networks and redox regulation is being revealed step by step, yet much still needs to be learned. Detailed knowledge of the molecular patterns generated from the principles of the redox code under defined physiological or pathological conditions in cells and organs will contribute to understanding the redox component in health and disease. Ultimately, there will be a scientific basis to a modern redox medicine.

  15. Z₂-double cyclic codes

    OpenAIRE

    Borges, J.

    2014-01-01

    A binary linear code C is a Z2-double cyclic code if the set of coordinates can be partitioned into two subsets such that any cyclic shift of the coordinates of both subsets leaves invariant the code. These codes can be identified as submodules of the Z2[x]-module Z2[x]/(x^r − 1) × Z2[x]/(x^s − 1). We determine the structure of Z2-double cyclic codes giving the generator polynomials of these codes. The related polynomial representation of Z2-double cyclic codes and its duals, and the relation...

  16. Coding for urologic office procedures.

    Science.gov (United States)

    Dowling, Robert A; Painter, Mark

    2013-11-01

    This article summarizes current best practices for documenting, coding, and billing common office-based urologic procedures. Topics covered include general principles, basic and advanced urologic coding, creation of medical records that support compliant coding practices, bundled codes and unbundling, global periods, modifiers for procedure codes, when to bill for evaluation and management services during the same visit, coding for supplies, and laboratory and radiology procedures pertinent to urology practice. Detailed information is included for the most common urology office procedures, and suggested resources and references are provided. This information is of value to physicians, office managers, and their coding staff. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Essential idempotents and simplex codes

    Directory of Open Access Journals (Sweden)

    Gladys Chalom

    2017-01-01

    Full Text Available We define essential idempotents in group algebras and use them to prove that every mininmal abelian non-cyclic code is a repetition code. Also we use them to prove that every minimal abelian code is equivalent to a minimal cyclic code of the same length. Finally, we show that a binary cyclic code is simplex if and only if is of length of the form $n=2^k-1$ and is generated by an essential idempotent.

  18. Rate-adaptive BCH codes for distributed source coding

    DEFF Research Database (Denmark)

    Salmistraro, Matteo; Larsen, Knud J.; Forchhammer, Søren

    2013-01-01

    This paper considers Bose-Chaudhuri-Hocquenghem (BCH) codes for distributed source coding. A feedback channel is employed to adapt the rate of the code during the decoding process. The focus is on codes with short block lengths for independently coding a binary source X and decoding it given its...... strategies for improving the reliability of the decoded result are analyzed, and methods for estimating the performance are proposed. In the analysis, noiseless feedback and noiseless communication are assumed. Simulation results show that rate-adaptive BCH codes achieve better performance than low...... correlated side information Y. The proposed codes have been analyzed in a high-correlation scenario, where the marginal probability of each symbol, Xi in X, given Y is highly skewed (unbalanced). Rate-adaptive BCH codes are presented and applied to distributed source coding. Adaptive and fixed checking...

  19. Entanglement-assisted quantum MDS codes constructed from negacyclic codes

    Science.gov (United States)

    Chen, Jianzhang; Huang, Yuanyuan; Feng, Chunhui; Chen, Riqing

    2017-12-01

    Recently, entanglement-assisted quantum codes have been constructed from cyclic codes by some scholars. However, how to determine the number of shared pairs required to construct entanglement-assisted quantum codes is not an easy work. In this paper, we propose a decomposition of the defining set of negacyclic codes. Based on this method, four families of entanglement-assisted quantum codes constructed in this paper satisfy the entanglement-assisted quantum Singleton bound, where the minimum distance satisfies q+1 ≤ d≤ n+2/2. Furthermore, we construct two families of entanglement-assisted quantum codes with maximal entanglement.

  20. Parametric studies of radiolytic oxidation of iodide solutions with and without paint: comparison with code calculations

    Energy Technology Data Exchange (ETDEWEB)

    Poletiko, C; Hueber, C [Inst. de Protection et de Surete Nucleaire, C.E. Cadarache, St. Paul-lez-Durance (France); Fabre, B [CISI, C.E. Cadarache, St. Paul-lez-Durance (France)

    1996-12-01

    In case of severe nuclear accident, radioactive material may be released into the environment. Among the fission products involved, are the very volatile iodine isotopes. However, the chemical forms are not well known due to the presence of different species in the containment with which iodine may rapidly react to form aerosols, molecular iodine, hydroiodic acid and iodo-organics. Tentative explanations of different mechanisms were performed through benchscale tests. A series of tests has been performed at AEA Harwell (GB) to study parameters such as pH, dose rate, concentration, gas flow rate, temperature in relation to molecular iodine production, under dynamic conditions. Another set of tests has been performed in AECL Whiteshell (CA) to study the behaviour of painted coupons, standing in gas phase or liquid phase or both, with iodine compounds under radiation. The purpose of our paper is to synthesize the data and compare the results to the IODE code calculation. Some parameters of the code were studied to fit the experimental result the best. A law, concerning the reverse reaction of iodide radiolytic oxidation, has been proposed versus: pH, concentrations and gas flow-rate. This law does not apply for dose rate variations. For the study of painted coupons, it has been pointed out that molecular iodine tends to be adsorbed or chemically absorbed on the surface in gas phase, but the mechanism should be more sophisticated in the aqueous phase. The iodo-organics present in liquid phase tend to be partly or totally destroyed by oxidation under radiation (depending upon the dose delivered). These points are discussed. (author) 18 figs., 3 tabs., 15 refs.

  1. Efficient convolutional sparse coding

    Science.gov (United States)

    Wohlberg, Brendt

    2017-06-20

    Computationally efficient algorithms may be applied for fast dictionary learning solving the convolutional sparse coding problem in the Fourier domain. More specifically, efficient convolutional sparse coding may be derived within an alternating direction method of multipliers (ADMM) framework that utilizes fast Fourier transforms (FFT) to solve the main linear system in the frequency domain. Such algorithms may enable a significant reduction in computational cost over conventional approaches by implementing a linear solver for the most critical and computationally expensive component of the conventional iterative algorithm. The theoretical computational cost of the algorithm may be reduced from O(M.sup.3N) to O(MN log N), where N is the dimensionality of the data and M is the number of elements in the dictionary. This significant improvement in efficiency may greatly increase the range of problems that can practically be addressed via convolutional sparse representations.

  2. Coded Network Function Virtualization

    DEFF Research Database (Denmark)

    Al-Shuwaili, A.; Simone, O.; Kliewer, J.

    2016-01-01

    Network function virtualization (NFV) prescribes the instantiation of network functions on general-purpose network devices, such as servers and switches. While yielding a more flexible and cost-effective network architecture, NFV is potentially limited by the fact that commercial off......-the-shelf hardware is less reliable than the dedicated network elements used in conventional cellular deployments. The typical solution for this problem is to duplicate network functions across geographically distributed hardware in order to ensure diversity. In contrast, this letter proposes to leverage channel...... coding in order to enhance the robustness on NFV to hardware failure. The proposed approach targets the network function of uplink channel decoding, and builds on the algebraic structure of the encoded data frames in order to perform in-network coding on the signals to be processed at different servers...

  3. The NIMROD Code

    Science.gov (United States)

    Schnack, D. D.; Glasser, A. H.

    1996-11-01

    NIMROD is a new code system that is being developed for the analysis of modern fusion experiments. It is being designed from the beginning to make the maximum use of massively parallel computer architectures and computer graphics. The NIMROD physics kernel solves the three-dimensional, time-dependent two-fluid equations with neo-classical effects in toroidal geometry of arbitrary poloidal cross section. The NIMROD system also includes a pre-processor, a grid generator, and a post processor. User interaction with NIMROD is facilitated by a modern graphical user interface (GUI). The NIMROD project is using Quality Function Deployment (QFD) team management techniques to minimize re-engineering and reduce code development time. This paper gives an overview of the NIMROD project. Operation of the GUI is demonstrated, and the first results from the physics kernel are given.

  4. Computer code FIT

    International Nuclear Information System (INIS)

    Rohmann, D.; Koehler, T.

    1987-02-01

    This is a description of the computer code FIT, written in FORTRAN-77 for a PDP 11/34. FIT is an interactive program to decude position, width and intensity of lines of X-ray spectra (max. length of 4K channels). The lines (max. 30 lines per fit) may have Gauss- or Voigt-profile, as well as exponential tails. Spectrum and fit can be displayed on a Tektronix terminal. (orig.) [de

  5. Discrete Sparse Coding.

    Science.gov (United States)

    Exarchakis, Georgios; Lücke, Jörg

    2017-11-01

    Sparse coding algorithms with continuous latent variables have been the subject of a large number of studies. However, discrete latent spaces for sparse coding have been largely ignored. In this work, we study sparse coding with latents described by discrete instead of continuous prior distributions. We consider the general case in which the latents (while being sparse) can take on any value of a finite set of possible values and in which we learn the prior probability of any value from data. This approach can be applied to any data generated by discrete causes, and it can be applied as an approximation of continuous causes. As the prior probabilities are learned, the approach then allows for estimating the prior shape without assuming specific functional forms. To efficiently train the parameters of our probabilistic generative model, we apply a truncated expectation-maximization approach (expectation truncation) that we modify to work with a general discrete prior. We evaluate the performance of the algorithm by applying it to a variety of tasks: (1) we use artificial data to verify that the algorithm can recover the generating parameters from a random initialization, (2) use image patches of natural images and discuss the role of the prior for the extraction of image components, (3) use extracellular recordings of neurons to present a novel method of analysis for spiking neurons that includes an intuitive discretization strategy, and (4) apply the algorithm on the task of encoding audio waveforms of human speech. The diverse set of numerical experiments presented in this letter suggests that discrete sparse coding algorithms can scale efficiently to work with realistic data sets and provide novel statistical quantities to describe the structure of the data.

  6. Code of Practice

    International Nuclear Information System (INIS)

    Doyle, Colin; Hone, Christopher; Nowlan, N.V.

    1984-05-01

    This Code of Practice introduces accepted safety procedures associated with the use of alpha, beta, gamma and X-radiation in secondary schools (pupils aged 12 to 18) in Ireland, and summarises good practice and procedures as they apply to radiation protection. Typical dose rates at various distances from sealed sources are quoted, and simplified equations are used to demonstrate dose and shielding calculations. The regulatory aspects of radiation protection are outlined, and references to statutory documents are given

  7. Tokamak simulation code manual

    International Nuclear Information System (INIS)

    Chung, Moon Kyoo; Oh, Byung Hoon; Hong, Bong Keun; Lee, Kwang Won

    1995-01-01

    The method to use TSC (Tokamak Simulation Code) developed by Princeton plasma physics laboratory is illustrated. In KT-2 tokamak, time dependent simulation of axisymmetric toroidal plasma and vertical stability have to be taken into account in design phase using TSC. In this report physical modelling of TSC are described and examples of application in JAERI and SERI are illustrated, which will be useful when TSC is installed KAERI computer system. (Author) 15 refs., 6 figs., 3 tabs

  8. Status of MARS Code

    Energy Technology Data Exchange (ETDEWEB)

    N.V. Mokhov

    2003-04-09

    Status and recent developments of the MARS 14 Monte Carlo code system for simulation of hadronic and electromagnetic cascades in shielding, accelerator and detector components in the energy range from a fraction of an electronvolt up to 100 TeV are described. these include physics models both in strong and electromagnetic interaction sectors, variance reduction techniques, residual dose, geometry, tracking, histograming. MAD-MARS Beam Line Build and Graphical-User Interface.

  9. Codes of Good Governance

    DEFF Research Database (Denmark)

    Beck Jørgensen, Torben; Sørensen, Ditte-Lene

    2013-01-01

    Good governance is a broad concept used by many international organizations to spell out how states or countries should be governed. Definitions vary, but there is a clear core of common public values, such as transparency, accountability, effectiveness, and the rule of law. It is quite likely......, transparency, neutrality, impartiality, effectiveness, accountability, and legality. The normative context of public administration, as expressed in codes, seems to ignore the New Public Management and Reinventing Government reform movements....

  10. Orthopedics coding and funding.

    Science.gov (United States)

    Baron, S; Duclos, C; Thoreux, P

    2014-02-01

    The French tarification à l'activité (T2A) prospective payment system is a financial system in which a health-care institution's resources are based on performed activity. Activity is described via the PMSI medical information system (programme de médicalisation du système d'information). The PMSI classifies hospital cases by clinical and economic categories known as diagnosis-related groups (DRG), each with an associated price tag. Coding a hospital case involves giving as realistic a description as possible so as to categorize it in the right DRG and thus ensure appropriate payment. For this, it is essential to understand what determines the pricing of inpatient stay: namely, the code for the surgical procedure, the patient's principal diagnosis (reason for admission), codes for comorbidities (everything that adds to management burden), and the management of the length of inpatient stay. The PMSI is used to analyze the institution's activity and dynamism: change on previous year, relation to target, and comparison with competing institutions based on indicators such as the mean length of stay performance indicator (MLS PI). The T2A system improves overall care efficiency. Quality of care, however, is not presently taken account of in the payment made to the institution, as there are no indicators for this; work needs to be done on this topic. Copyright © 2014. Published by Elsevier Masson SAS.

  11. Code Modernization of VPIC

    Science.gov (United States)

    Bird, Robert; Nystrom, David; Albright, Brian

    2017-10-01

    The ability of scientific simulations to effectively deliver performant computation is increasingly being challenged by successive generations of high-performance computing architectures. Code development to support efficient computation on these modern architectures is both expensive, and highly complex; if it is approached without due care, it may also not be directly transferable between subsequent hardware generations. Previous works have discussed techniques to support the process of adapting a legacy code for modern hardware generations, but despite the breakthroughs in the areas of mini-app development, portable-performance, and cache oblivious algorithms the problem still remains largely unsolved. In this work we demonstrate how a focus on platform agnostic modern code-development can be applied to Particle-in-Cell (PIC) simulations to facilitate effective scientific delivery. This work builds directly on our previous work optimizing VPIC, in which we replaced intrinsic based vectorisation with compile generated auto-vectorization to improve the performance and portability of VPIC. In this work we present the use of a specialized SIMD queue for processing some particle operations, and also preview a GPU capable OpenMP variant of VPIC. Finally we include a lessons learnt. Work performed under the auspices of the U.S. Dept. of Energy by the Los Alamos National Security, LLC Los Alamos National Laboratory under contract DE-AC52-06NA25396 and supported by the LANL LDRD program.

  12. MELCOR computer code manuals

    Energy Technology Data Exchange (ETDEWEB)

    Summers, R.M.; Cole, R.K. Jr.; Smith, R.C.; Stuart, D.S.; Thompson, S.L. [Sandia National Labs., Albuquerque, NM (United States); Hodge, S.A.; Hyman, C.R.; Sanders, R.L. [Oak Ridge National Lab., TN (United States)

    1995-03-01

    MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor nuclear power plants. MELCOR is being developed at Sandia National Laboratories for the U.S. Nuclear Regulatory Commission as a second-generation plant risk assessment tool and the successor to the Source Term Code Package. A broad spectrum of severe accident phenomena in both boiling and pressurized water reactors is treated in MELCOR in a unified framework. These include: thermal-hydraulic response in the reactor coolant system, reactor cavity, containment, and confinement buildings; core heatup, degradation, and relocation; core-concrete attack; hydrogen production, transport, and combustion; fission product release and transport; and the impact of engineered safety features on thermal-hydraulic and radionuclide behavior. Current uses of MELCOR include estimation of severe accident source terms and their sensitivities and uncertainties in a variety of applications. This publication of the MELCOR computer code manuals corresponds to MELCOR 1.8.3, released to users in August, 1994. Volume 1 contains a primer that describes MELCOR`s phenomenological scope, organization (by package), and documentation. The remainder of Volume 1 contains the MELCOR Users Guides, which provide the input instructions and guidelines for each package. Volume 2 contains the MELCOR Reference Manuals, which describe the phenomenological models that have been implemented in each package.

  13. MELCOR computer code manuals

    International Nuclear Information System (INIS)

    Summers, R.M.; Cole, R.K. Jr.; Smith, R.C.; Stuart, D.S.; Thompson, S.L.; Hodge, S.A.; Hyman, C.R.; Sanders, R.L.

    1995-03-01

    MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor nuclear power plants. MELCOR is being developed at Sandia National Laboratories for the U.S. Nuclear Regulatory Commission as a second-generation plant risk assessment tool and the successor to the Source Term Code Package. A broad spectrum of severe accident phenomena in both boiling and pressurized water reactors is treated in MELCOR in a unified framework. These include: thermal-hydraulic response in the reactor coolant system, reactor cavity, containment, and confinement buildings; core heatup, degradation, and relocation; core-concrete attack; hydrogen production, transport, and combustion; fission product release and transport; and the impact of engineered safety features on thermal-hydraulic and radionuclide behavior. Current uses of MELCOR include estimation of severe accident source terms and their sensitivities and uncertainties in a variety of applications. This publication of the MELCOR computer code manuals corresponds to MELCOR 1.8.3, released to users in August, 1994. Volume 1 contains a primer that describes MELCOR's phenomenological scope, organization (by package), and documentation. The remainder of Volume 1 contains the MELCOR Users Guides, which provide the input instructions and guidelines for each package. Volume 2 contains the MELCOR Reference Manuals, which describe the phenomenological models that have been implemented in each package

  14. Quality Improvement of MARS Code and Establishment of Code Coupling

    International Nuclear Information System (INIS)

    Chung, Bub Dong; Jeong, Jae Jun; Kim, Kyung Doo

    2010-04-01

    The improvement of MARS code quality and coupling with regulatory auditing code have been accomplished for the establishment of self-reliable technology based regulatory auditing system. The unified auditing system code was realized also by implementing the CANDU specific models and correlations. As a part of the quality assurance activities, the various QA reports were published through the code assessments. The code manuals were updated and published a new manual which describe the new models and correlations. The code coupling methods were verified though the exercise of plant application. The education-training seminar and technology transfer were performed for the code users. The developed MARS-KS is utilized as reliable auditing tool for the resolving the safety issue and other regulatory calculations. The code can be utilized as a base technology for GEN IV reactor applications

  15. Design of convolutional tornado code

    Science.gov (United States)

    Zhou, Hui; Yang, Yao; Gao, Hongmin; Tan, Lu

    2017-09-01

    As a linear block code, the traditional tornado (tTN) code is inefficient in burst-erasure environment and its multi-level structure may lead to high encoding/decoding complexity. This paper presents a convolutional tornado (cTN) code which is able to improve the burst-erasure protection capability by applying the convolution property to the tTN code, and reduce computational complexity by abrogating the multi-level structure. The simulation results show that cTN code can provide a better packet loss protection performance with lower computation complexity than tTN code.

  16. Random linear codes in steganography

    Directory of Open Access Journals (Sweden)

    Kamil Kaczyński

    2016-12-01

    Full Text Available Syndrome coding using linear codes is a technique that allows improvement in the steganographic algorithms parameters. The use of random linear codes gives a great flexibility in choosing the parameters of the linear code. In parallel, it offers easy generation of parity check matrix. In this paper, the modification of LSB algorithm is presented. A random linear code [8, 2] was used as a base for algorithm modification. The implementation of the proposed algorithm, along with practical evaluation of algorithms’ parameters based on the test images was made.[b]Keywords:[/b] steganography, random linear codes, RLC, LSB

  17. Containment Code Validation Matrix

    International Nuclear Information System (INIS)

    Chin, Yu-Shan; Mathew, P.M.; Glowa, Glenn; Dickson, Ray; Liang, Zhe; Leitch, Brian; Barber, Duncan; Vasic, Aleks; Bentaib, Ahmed; Journeau, Christophe; Malet, Jeanne; Studer, Etienne; Meynet, Nicolas; Piluso, Pascal; Gelain, Thomas; Michielsen, Nathalie; Peillon, Samuel; Porcheron, Emmanuel; Albiol, Thierry; Clement, Bernard; Sonnenkalb, Martin; Klein-Hessling, Walter; Arndt, Siegfried; Weber, Gunter; Yanez, Jorge; Kotchourko, Alexei; Kuznetsov, Mike; Sangiorgi, Marco; Fontanet, Joan; Herranz, Luis; Garcia De La Rua, Carmen; Santiago, Aleza Enciso; Andreani, Michele; Paladino, Domenico; Dreier, Joerg; Lee, Richard; Amri, Abdallah

    2014-01-01

    The Committee on the Safety of Nuclear Installations (CSNI) formed the CCVM (Containment Code Validation Matrix) task group in 2002. The objective of this group was to define a basic set of available experiments for code validation, covering the range of containment (ex-vessel) phenomena expected in the course of light and heavy water reactor design basis accidents and beyond design basis accidents/severe accidents. It was to consider phenomena relevant to pressurised heavy water reactor (PHWR), pressurised water reactor (PWR) and boiling water reactor (BWR) designs of Western origin as well as of Eastern European VVER types. This work would complement the two existing CSNI validation matrices for thermal hydraulic code validation (NEA/CSNI/R(1993)14) and In-vessel core degradation (NEA/CSNI/R(2001)21). The report initially provides a brief overview of the main features of a PWR, BWR, CANDU and VVER reactors. It also provides an overview of the ex-vessel corium retention (core catcher). It then provides a general overview of the accident progression for light water and heavy water reactors. The main focus is to capture most of the phenomena and safety systems employed in these reactor types and to highlight the differences. This CCVM contains a description of 127 phenomena, broken down into 6 categories: - Containment Thermal-hydraulics Phenomena; - Hydrogen Behaviour (Combustion, Mitigation and Generation) Phenomena; - Aerosol and Fission Product Behaviour Phenomena; - Iodine Chemistry Phenomena; - Core Melt Distribution and Behaviour in Containment Phenomena; - Systems Phenomena. A synopsis is provided for each phenomenon, including a description, references for further information, significance for DBA and SA/BDBA and a list of experiments that may be used for code validation. The report identified 213 experiments, broken down into the same six categories (as done for the phenomena). An experiment synopsis is provided for each test. Along with a test description

  18. Decoding of concatenated codes with interleaved outer codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Høholdt, Tom; Thommesen, Christian

    2004-01-01

    Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved (N, K) Reed-Solomon codes, which allows close to N-K errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes.......Recently Bleichenbacher et al. proposed a decoding algorithm for interleaved (N, K) Reed-Solomon codes, which allows close to N-K errors to be corrected in many cases. We discuss the application of this decoding algorithm to concatenated codes....

  19. TASS code topical report. V.1 TASS code technical manual

    International Nuclear Information System (INIS)

    Sim, Suk K.; Chang, W. P.; Kim, K. D.; Kim, H. C.; Yoon, H. Y.

    1997-02-01

    TASS 1.0 code has been developed at KAERI for the initial and reload non-LOCA safety analysis for the operating PWRs as well as the PWRs under construction in Korea. TASS code will replace various vendor's non-LOCA safety analysis codes currently used for the Westinghouse and ABB-CE type PWRs in Korea. This can be achieved through TASS code input modifications specific to each reactor type. The TASS code can be run interactively through the keyboard operation. A simimodular configuration used in developing the TASS code enables the user easily implement new models. TASS code has been programmed using FORTRAN77 which makes it easy to install and port for different computer environments. The TASS code can be utilized for the steady state simulation as well as the non-LOCA transient simulations such as power excursions, reactor coolant pump trips, load rejections, loss of feedwater, steam line breaks, steam generator tube ruptures, rod withdrawal and drop, and anticipated transients without scram (ATWS). The malfunctions of the control systems, components, operator actions and the transients caused by the malfunctions can be easily simulated using the TASS code. This technical report describes the TASS 1.0 code models including reactor thermal hydraulic, reactor core and control models. This TASS code models including reactor thermal hydraulic, reactor core and control models. This TASS code technical manual has been prepared as a part of the TASS code manual which includes TASS code user's manual and TASS code validation report, and will be submitted to the regulatory body as a TASS code topical report for a licensing non-LOCA safety analysis for the Westinghouse and ABB-CE type PWRs operating and under construction in Korea. (author). 42 refs., 29 tabs., 32 figs

  20. Construction of new quantum MDS codes derived from constacyclic codes

    Science.gov (United States)

    Taneja, Divya; Gupta, Manish; Narula, Rajesh; Bhullar, Jaskaran

    Obtaining quantum maximum distance separable (MDS) codes from dual containing classical constacyclic codes using Hermitian construction have paved a path to undertake the challenges related to such constructions. Using the same technique, some new parameters of quantum MDS codes have been constructed here. One set of parameters obtained in this paper has achieved much larger distance than work done earlier. The remaining constructed parameters of quantum MDS codes have large minimum distance and were not explored yet.

  1. Combinatorial neural codes from a mathematical coding theory perspective.

    Science.gov (United States)

    Curto, Carina; Itskov, Vladimir; Morrison, Katherine; Roth, Zachary; Walker, Judy L

    2013-07-01

    Shannon's seminal 1948 work gave rise to two distinct areas of research: information theory and mathematical coding theory. While information theory has had a strong influence on theoretical neuroscience, ideas from mathematical coding theory have received considerably less attention. Here we take a new look at combinatorial neural codes from a mathematical coding theory perspective, examining the error correction capabilities of familiar receptive field codes (RF codes). We find, perhaps surprisingly, that the high levels of redundancy present in these codes do not support accurate error correction, although the error-correcting performance of receptive field codes catches up to that of random comparison codes when a small tolerance to error is introduced. However, receptive field codes are good at reflecting distances between represented stimuli, while the random comparison codes are not. We suggest that a compromise in error-correcting capability may be a necessary price to pay for a neural code whose structure serves not only error correction, but must also reflect relationships between stimuli.

  2. Convolutional coding techniques for data protection

    Science.gov (United States)

    Massey, J. L.

    1975-01-01

    Results of research on the use of convolutional codes in data communications are presented. Convolutional coding fundamentals are discussed along with modulation and coding interaction. Concatenated coding systems and data compression with convolutional codes are described.

  3. High Energy Transport Code HETC

    International Nuclear Information System (INIS)

    Gabriel, T.A.

    1985-09-01

    The physics contained in the High Energy Transport Code (HETC), in particular the collision models, are discussed. An application using HETC as part of the CALOR code system is also given. 19 refs., 5 figs., 3 tabs

  4. Code stroke in Asturias.

    Science.gov (United States)

    Benavente, L; Villanueva, M J; Vega, P; Casado, I; Vidal, J A; Castaño, B; Amorín, M; de la Vega, V; Santos, H; Trigo, A; Gómez, M B; Larrosa, D; Temprano, T; González, M; Murias, E; Calleja, S

    2016-04-01

    Intravenous thrombolysis with alteplase is an effective treatment for ischaemic stroke when applied during the first 4.5 hours, but less than 15% of patients have access to this technique. Mechanical thrombectomy is more frequently able to recanalise proximal occlusions in large vessels, but the infrastructure it requires makes it even less available. We describe the implementation of code stroke in Asturias, as well as the process of adapting various existing resources for urgent stroke care in the region. By considering these resources, and the demographic and geographic circumstances of our region, we examine ways of reorganising the code stroke protocol that would optimise treatment times and provide the most appropriate treatment for each patient. We distributed the 8 health districts in Asturias so as to permit referral of candidates for reperfusion therapies to either of the 2 hospitals with 24-hour stroke units and on-call neurologists and providing IV fibrinolysis. Hospitals were assigned according to proximity and stroke severity; the most severe cases were immediately referred to the hospital with on-call interventional neurology care. Patient triage was provided by pre-hospital emergency services according to the NIHSS score. Modifications to code stroke in Asturias have allowed us to apply reperfusion therapies with good results, while emphasising equitable care and managing the severity-time ratio to offer the best and safest treatment for each patient as soon as possible. Copyright © 2015 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

  5. Decoding Xing-Ling codes

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Refslund

    2002-01-01

    This paper describes an efficient decoding method for a recent construction of good linear codes as well as an extension to the construction. Furthermore, asymptotic properties and list decoding of the codes are discussed.......This paper describes an efficient decoding method for a recent construction of good linear codes as well as an extension to the construction. Furthermore, asymptotic properties and list decoding of the codes are discussed....

  6. WWER reactor physics code applications

    International Nuclear Information System (INIS)

    Gado, J.; Kereszturi, A.; Gacs, A.; Telbisz, M.

    1994-01-01

    The coupled steady-state reactor physics and thermohydraulic code system KARATE has been developed and applied for WWER-1000 and WWER-440 operational calculations. The 3 D coupled kinetic code KIKO3D has been developed and validated for WWER-440 accident analysis applications. The coupled kinetic code SMARTA developed by VTT Helsinki has been applied for WWER-440 accident analysis. The paper gives a summary of the experience in code development and application. (authors). 10 refs., 2 tabs., 5 figs

  7. The path of code linting

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Join the path of code linting and discover how it can help you reach higher levels of programming enlightenment. Today we will cover how to embrace code linters to offload cognitive strain on preserving style standards in your code base as well as avoiding error-prone constructs. Additionally, I will show you the journey ahead for integrating several code linters in the programming tools your already use with very little effort.

  8. The CORSYS neutronics code system

    International Nuclear Information System (INIS)

    Caner, M.; Krumbein, A.D.; Saphier, D.; Shapira, M.

    1994-01-01

    The purpose of this work is to assemble a code package for LWR core physics including coupled neutronics, burnup and thermal hydraulics. The CORSYS system is built around the cell code WIMS (for group microscopic cross section calculations) and 3-dimension diffusion code CITATION (for burnup and fuel management). We are implementing such a system on an IBM RS-6000 workstation. The code was rested with a simplified model of the Zion Unit 2 PWR. (authors). 6 refs., 8 figs., 1 tabs

  9. Bar codes for nuclear safeguards

    International Nuclear Information System (INIS)

    Keswani, A.N.; Bieber, A.M. Jr.

    1983-01-01

    Bar codes similar to those used in supermarkets can be used to reduce the effort and cost of collecting nuclear materials accountability data. A wide range of equipment is now commercially available for printing and reading bar-coded information. Several examples of each of the major types of commercially available equipment are given, and considerations are discussed both for planning systems using bar codes and for choosing suitable bar code equipment

  10. Bar codes for nuclear safeguards

    International Nuclear Information System (INIS)

    Keswani, A.N.; Bieber, A.M.

    1983-01-01

    Bar codes similar to those used in supermarkets can be used to reduce the effort and cost of collecting nuclear materials accountability data. A wide range of equipment is now commercially available for printing and reading bar-coded information. Several examples of each of the major types of commercially-available equipment are given, and considerations are discussed both for planning systems using bar codes and for choosing suitable bar code equipment

  11. Quick response codes in Orthodontics

    Directory of Open Access Journals (Sweden)

    Moidin Shakil

    2015-01-01

    Full Text Available Quick response (QR code codes are two-dimensional barcodes, which encodes for a large amount of information. QR codes in Orthodontics are an innovative approach in which patient details, radiographic interpretation, and treatment plan can be encoded. Implementing QR code in Orthodontics will save time, reduces paperwork, and minimizes manual efforts in storage and retrieval of patient information during subsequent stages of treatment.

  12. Multiple LDPC decoding for distributed source coding and video coding

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Luong, Huynh Van; Huang, Xin

    2011-01-01

    Distributed source coding (DSC) is a coding paradigm for systems which fully or partly exploit the source statistics at the decoder to reduce the computational burden at the encoder. Distributed video coding (DVC) is one example. This paper considers the use of Low Density Parity Check Accumulate...... (LDPCA) codes in a DSC scheme with feed-back. To improve the LDPC coding performance in the context of DSC and DVC, while retaining short encoder blocks, this paper proposes multiple parallel LDPC decoding. The proposed scheme passes soft information between decoders to enhance performance. Experimental...

  13. Cinder begin creative coding

    CERN Document Server

    Rijnieks, Krisjanis

    2013-01-01

    Presented in an easy to follow, tutorial-style format, this book will lead you step-by-step through the multi-faceted uses of Cinder.""Cinder: Begin Creative Coding"" is for people who already have experience in programming. It can serve as a transition from a previous background in Processing, Java in general, JavaScript, openFrameworks, C++ in general or ActionScript to the framework covered in this book, namely Cinder. If you like quick and easy to follow tutorials that will let yousee progress in less than an hour - this book is for you. If you are searching for a book that will explain al

  14. UNSPEC: revisited (semaphore code)

    International Nuclear Information System (INIS)

    Neifert, R.D.

    1981-01-01

    The UNSPEC code is used to solve the problem of unfolding an observed x-ray spectrum given the response matrix of the measuring system and the measured signal values. UNSPEC uses an iterative technique to solve the unfold problem. Due to experimental errors in the measured signal values and/or computer round-off errors, discontinuities and oscillatory behavior may occur in the iterated spectrum. These can be suppressed by smoothing the results after each iteration. Input/output options and control cards are explained; sample input and output are provided

  15. The FLIC conversion codes

    International Nuclear Information System (INIS)

    Basher, J.C.

    1965-05-01

    This report describes the FORTRAN programmes, FLIC 1 and FLIC 2. These programmes convert programmes coded in one dialect of FORTRAN to another dialect of the same language. FLIC 1 is a general pattern recognition and replacement programme whereas FLIC 2 contains extensions directed towards the conversion of FORTRAN II and S2 programmes to EGTRAN 1 - the dialect now in use on the Winfrith KDF9. FII or S2 statements are replaced where possible by their E1 equivalents; other statements which may need changing are flagged. (author)

  16. SPRAY code user's report

    International Nuclear Information System (INIS)

    Shire, P.R.

    1977-03-01

    The SPRAY computer code has been developed to model the effects of postulated sodium spray release from LMFBR piping within containment chambers. The calculation method utilizes gas convection, heat transfer and droplet combustion theory to calculate the pressure and temperature effects within the enclosure. The applicable range is 0-21 mol percent oxygen and .02-.30 inch droplets with or without humidity. Droplet motion and large sodium surface area combine to produce rapid heat release and pressure rise within the enclosed volume

  17. The FLIC conversion codes

    Energy Technology Data Exchange (ETDEWEB)

    Basher, J C [General Reactor Physics Division, Atomic Energy Establishment, Winfrith, Dorchester, Dorset (United Kingdom)

    1965-05-15

    This report describes the FORTRAN programmes, FLIC 1 and FLIC 2. These programmes convert programmes coded in one dialect of FORTRAN to another dialect of the same language. FLIC 1 is a general pattern recognition and replacement programme whereas FLIC 2 contains extensions directed towards the conversion of FORTRAN II and S2 programmes to EGTRAN 1 - the dialect now in use on the Winfrith KDF9. FII or S2 statements are replaced where possible by their E1 equivalents; other statements which may need changing are flagged. (author)

  18. Code Generation with Templates

    CERN Document Server

    Arnoldus, Jeroen; Serebrenik, A

    2012-01-01

    Templates are used to generate all kinds of text, including computer code. The last decade, the use of templates gained a lot of popularity due to the increase of dynamic web applications. Templates are a tool for programmers, and implementations of template engines are most times based on practical experience rather than based on a theoretical background. This book reveals the mathematical background of templates and shows interesting findings for improving the practical use of templates. First, a framework to determine the necessary computational power for the template metalanguage is presen

  19. Order functions and evaluation codes

    DEFF Research Database (Denmark)

    Høholdt, Tom; Pellikaan, Ruud; van Lint, Jack

    1997-01-01

    Based on the notion of an order function we construct and determine the parameters of a class of error-correcting evaluation codes. This class includes the one-point algebraic geometry codes as wella s the generalized Reed-Muller codes and the parameters are detremined without using the heavy...... machinery of algebraic geometry....

  20. Direct-semidirect (DSD) codes

    International Nuclear Information System (INIS)

    Cvelbar, F.

    1999-01-01

    Recent codes for direct-semidirect (DSD) model calculations in the form of answers to a detailed questionnaire are reviewed. These codes include those embodying the classical DSD approach covering only the transitions to the bound states (RAF, HIKARI, and those of the Bologna group), as well as the code CUPIDO++ that also treats transitions to unbound states. (author)

  1. Dual Coding, Reasoning and Fallacies.

    Science.gov (United States)

    Hample, Dale

    1982-01-01

    Develops the theory that a fallacy is not a comparison of a rhetorical text to a set of definitions but a comparison of one person's cognition with another's. Reviews Paivio's dual coding theory, relates nonverbal coding to reasoning processes, and generates a limited fallacy theory based on dual coding theory. (PD)

  2. Strongly-MDS convolutional codes

    NARCIS (Netherlands)

    Gluesing-Luerssen, H; Rosenthal, J; Smarandache, R

    Maximum-distance separable (MDS) convolutional codes have the property that their free distance is maximal among all codes of the same rate and the same degree. In this paper, a class of MDS convolutional codes is introduced whose column distances reach the generalized Singleton bound at the

  3. Lattice polytopes in coding theory

    Directory of Open Access Journals (Sweden)

    Ivan Soprunov

    2015-05-01

    Full Text Available In this paper we discuss combinatorial questions about lattice polytopes motivated by recent results on minimum distance estimation for toric codes. We also include a new inductive bound for the minimum distance of generalized toric codes. As an application, we give new formulas for the minimum distance of generalized toric codes for special lattice point configurations.

  4. Computer codes for safety analysis

    International Nuclear Information System (INIS)

    Holland, D.F.

    1986-11-01

    Computer codes for fusion safety analysis have been under development in the United States for about a decade. This paper will discuss five codes that are currently under development by the Fusion Safety Program. The purpose and capability of each code will be presented, a sample given, followed by a discussion of the present status and future development plans

  5. Geochemical computer codes. A review

    International Nuclear Information System (INIS)

    Andersson, K.

    1987-01-01

    In this report a review of available codes is performed and some code intercomparisons are also discussed. The number of codes treating natural waters (groundwater, lake water, sea water) is large. Most geochemical computer codes treat equilibrium conditions, although some codes with kinetic capability are available. A geochemical equilibrium model consists of a computer code, solving a set of equations by some numerical method and a data base, consisting of thermodynamic data required for the calculations. There are some codes which treat coupled geochemical and transport modeling. Some of these codes solve the equilibrium and transport equations simultaneously while other solve the equations separately from each other. The coupled codes require a large computer capacity and have thus as yet limited use. Three code intercomparisons have been found in literature. It may be concluded that there are many codes available for geochemical calculations but most of them require a user that us quite familiar with the code. The user also has to know the geochemical system in order to judge the reliability of the results. A high quality data base is necessary to obtain a reliable result. The best results may be expected for the major species of natural waters. For more complicated problems, including trace elements, precipitation/dissolution, adsorption, etc., the results seem to be less reliable. (With 44 refs.) (author)

  6. Separate Turbo Code and Single Turbo Code Adaptive OFDM Transmissions

    Directory of Open Access Journals (Sweden)

    Lei Ye

    2009-01-01

    Full Text Available This paper discusses the application of adaptive modulation and adaptive rate turbo coding to orthogonal frequency-division multiplexing (OFDM, to increase throughput on the time and frequency selective channel. The adaptive turbo code scheme is based on a subband adaptive method, and compares two adaptive systems: a conventional approach where a separate turbo code is used for each subband, and a single turbo code adaptive system which uses a single turbo code over all subbands. Five modulation schemes (BPSK, QPSK, 8AMPM, 16QAM, and 64QAM are employed and turbo code rates considered are 1/2 and 1/3. The performances of both systems with high (10−2 and low (10−4 BER targets are compared. Simulation results for throughput and BER show that the single turbo code adaptive system provides a significant improvement.

  7. New quantum codes constructed from quaternary BCH codes

    Science.gov (United States)

    Xu, Gen; Li, Ruihu; Guo, Luobin; Ma, Yuena

    2016-10-01

    In this paper, we firstly study construction of new quantum error-correcting codes (QECCs) from three classes of quaternary imprimitive BCH codes. As a result, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing quaternary BCH codes are determined to be much larger than the result given according to Aly et al. (IEEE Trans Inf Theory 53:1183-1188, 2007) for each different code length. Thus, families of new QECCs are newly obtained, and the constructed QECCs have larger distance than those in the previous literature. Secondly, we apply a combinatorial construction to the imprimitive BCH codes with their corresponding primitive counterpart and construct many new linear quantum codes with good parameters, some of which have parameters exceeding the finite Gilbert-Varshamov bound for linear quantum codes.

  8. Quantum Codes From Cyclic Codes Over The Ring R 2

    International Nuclear Information System (INIS)

    Altinel, Alev; Güzeltepe, Murat

    2016-01-01

    Let R 2 denotes the ring F 2 + μF 2 + υ 2 + μυ F 2 + wF 2 + μwF 2 + υwF 2 + μυwF 2 . In this study, we construct quantum codes from cyclic codes over the ring R 2 , for arbitrary length n, with the restrictions μ 2 = 0, υ 2 = 0, w 2 = 0, μυ = υμ, μw = wμ, υw = wυ and μ (υw) = (μυ) w. Also, we give a necessary and sufficient condition for cyclic codes over R 2 that contains its dual. As a final point, we obtain the parameters of quantum error-correcting codes from cyclic codes over R 2 and we give an example of quantum error-correcting codes form cyclic codes over R 2 . (paper)

  9. Separate Turbo Code and Single Turbo Code Adaptive OFDM Transmissions

    Directory of Open Access Journals (Sweden)

    Burr Alister

    2009-01-01

    Full Text Available Abstract This paper discusses the application of adaptive modulation and adaptive rate turbo coding to orthogonal frequency-division multiplexing (OFDM, to increase throughput on the time and frequency selective channel. The adaptive turbo code scheme is based on a subband adaptive method, and compares two adaptive systems: a conventional approach where a separate turbo code is used for each subband, and a single turbo code adaptive system which uses a single turbo code over all subbands. Five modulation schemes (BPSK, QPSK, 8AMPM, 16QAM, and 64QAM are employed and turbo code rates considered are and . The performances of both systems with high ( and low ( BER targets are compared. Simulation results for throughput and BER show that the single turbo code adaptive system provides a significant improvement.

  10. Converter of a continuous code into the Grey code

    International Nuclear Information System (INIS)

    Gonchar, A.I.; TrUbnikov, V.R.

    1979-01-01

    Described is a converter of a continuous code into the Grey code used in a 12-charged precision amplitude-to-digital converter to decrease the digital component of spectrometer differential nonlinearity to +0.7% in the 98% range of the measured band. To construct the converter of a continuous code corresponding to the input signal amplitude into the Grey code used is the regularity in recycling of units and zeroes in each discharge of the Grey code in the case of a continuous change of the number of pulses of a continuous code. The converter is constructed on the elements of 155 series, the frequency of continuous code pulse passing at the converter input is 25 MHz

  11. Supervised Transfer Sparse Coding

    KAUST Repository

    Al-Shedivat, Maruan

    2014-07-27

    A combination of the sparse coding and transfer learn- ing techniques was shown to be accurate and robust in classification tasks where training and testing objects have a shared feature space but are sampled from differ- ent underlying distributions, i.e., belong to different do- mains. The key assumption in such case is that in spite of the domain disparity, samples from different domains share some common hidden factors. Previous methods often assumed that all the objects in the target domain are unlabeled, and thus the training set solely comprised objects from the source domain. However, in real world applications, the target domain often has some labeled objects, or one can always manually label a small num- ber of them. In this paper, we explore such possibil- ity and show how a small number of labeled data in the target domain can significantly leverage classifica- tion accuracy of the state-of-the-art transfer sparse cod- ing methods. We further propose a unified framework named supervised transfer sparse coding (STSC) which simultaneously optimizes sparse representation, domain transfer and classification. Experimental results on three applications demonstrate that a little manual labeling and then learning the model in a supervised fashion can significantly improve classification accuracy.

  12. Two-terminal video coding.

    Science.gov (United States)

    Yang, Yang; Stanković, Vladimir; Xiong, Zixiang; Zhao, Wei

    2009-03-01

    Following recent works on the rate region of the quadratic Gaussian two-terminal source coding problem and limit-approaching code designs, this paper examines multiterminal source coding of two correlated, i.e., stereo, video sequences to save the sum rate over independent coding of both sequences. Two multiterminal video coding schemes are proposed. In the first scheme, the left sequence of the stereo pair is coded by H.264/AVC and used at the joint decoder to facilitate Wyner-Ziv coding of the right video sequence. The first I-frame of the right sequence is successively coded by H.264/AVC Intracoding and Wyner-Ziv coding. An efficient stereo matching algorithm based on loopy belief propagation is then adopted at the decoder to produce pixel-level disparity maps between the corresponding frames of the two decoded video sequences on the fly. Based on the disparity maps, side information for both motion vectors and motion-compensated residual frames of the right sequence are generated at the decoder before Wyner-Ziv encoding. In the second scheme, source splitting is employed on top of classic and Wyner-Ziv coding for compression of both I-frames to allow flexible rate allocation between the two sequences. Experiments with both schemes on stereo video sequences using H.264/AVC, LDPC codes for Slepian-Wolf coding of the motion vectors, and scalar quantization in conjunction with LDPC codes for Wyner-Ziv coding of the residual coefficients give a slightly lower sum rate than separate H.264/AVC coding of both sequences at the same video quality.

  13. The Art of Readable Code

    CERN Document Server

    Boswell, Dustin

    2011-01-01

    As programmers, we've all seen source code that's so ugly and buggy it makes our brain ache. Over the past five years, authors Dustin Boswell and Trevor Foucher have analyzed hundreds of examples of "bad code" (much of it their own) to determine why they're bad and how they could be improved. Their conclusion? You need to write code that minimizes the time it would take someone else to understand it-even if that someone else is you. This book focuses on basic principles and practical techniques you can apply every time you write code. Using easy-to-digest code examples from different languag

  14. Sub-Transport Layer Coding

    DEFF Research Database (Denmark)

    Hansen, Jonas; Krigslund, Jeppe; Roetter, Daniel Enrique Lucani

    2014-01-01

    Packet losses in wireless networks dramatically curbs the performance of TCP. This paper introduces a simple coding shim that aids IP-layer traffic in lossy environments while being transparent to transport layer protocols. The proposed coding approach enables erasure correction while being...... oblivious to the congestion control algorithms of the utilised transport layer protocol. Although our coding shim is indifferent towards the transport layer protocol, we focus on the performance of TCP when ran on top of our proposed coding mechanism due to its widespread use. The coding shim provides gains...

  15. 75 FR 19944 - International Code Council: The Update Process for the International Codes and Standards

    Science.gov (United States)

    2010-04-16

    ... documents from ICC's Chicago District Office: International Code Council, 4051 W Flossmoor Road, Country... Energy Conservation Code. International Existing Building Code. International Fire Code. International...

  16. Polynomial weights and code constructions

    DEFF Research Database (Denmark)

    Massey, J; Costello, D; Justesen, Jørn

    1973-01-01

    polynomial included. This fundamental property is then used as the key to a variety of code constructions including 1) a simplified derivation of the binary Reed-Muller codes and, for any primepgreater than 2, a new extensive class ofp-ary "Reed-Muller codes," 2) a new class of "repeated-root" cyclic codes...... of long constraint length binary convolutional codes derived from2^r-ary Reed-Solomon codes, and 6) a new class ofq-ary "repeated-root" constacyclic codes with an algebraic decoding algorithm.......For any nonzero elementcof a general finite fieldGF(q), it is shown that the polynomials(x - c)^i, i = 0,1,2,cdots, have the "weight-retaining" property that any linear combination of these polynomials with coefficients inGF(q)has Hamming weight at least as great as that of the minimum degree...

  17. Introduction of SCIENCE code package

    International Nuclear Information System (INIS)

    Lu Haoliang; Li Jinggang; Zhu Ya'nan; Bai Ning

    2012-01-01

    The SCIENCE code package is a set of neutronics tools based on 2D assembly calculations and 3D core calculations. It is made up of APOLLO2F, SMART and SQUALE and used to perform the nuclear design and loading pattern analysis for the reactors on operation or under construction of China Guangdong Nuclear Power Group. The purpose of paper is to briefly present the physical and numerical models used in each computation codes of the SCIENCE code pack age, including the description of the general structure of the code package, the coupling relationship of APOLLO2-F transport lattice code and SMART core nodal code, and the SQUALE code used for processing the core maps. (authors)

  18. Elements of algebraic coding systems

    CERN Document Server

    Cardoso da Rocha, Jr, Valdemar

    2014-01-01

    Elements of Algebraic Coding Systems is an introductory text to algebraic coding theory. In the first chapter, you'll gain inside knowledge of coding fundamentals, which is essential for a deeper understanding of state-of-the-art coding systems. This book is a quick reference for those who are unfamiliar with this topic, as well as for use with specific applications such as cryptography and communication. Linear error-correcting block codes through elementary principles span eleven chapters of the text. Cyclic codes, some finite field algebra, Goppa codes, algebraic decoding algorithms, and applications in public-key cryptography and secret-key cryptography are discussed, including problems and solutions at the end of each chapter. Three appendices cover the Gilbert bound and some related derivations, a derivation of the Mac- Williams' identities based on the probability of undetected error, and two important tools for algebraic decoding-namely, the finite field Fourier transform and the Euclidean algorithm f...

  19. Microbial analysis of the buffer/container experiment at AECL`s Underground Research Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Stroes-Gascoyne, S; Hamon, C J; Haveman, S A; Delaney, T L [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs; Pedersen, K; Ekendahl, S; Jahromi, N; Arlinger, J; Hallbeck, L [Univ. of Goeteborg, (Sweden). Dept. of General and Marine Microbiology; Daumas, S; Dekeyser, K [Guiges Recherche Appliquee en Microbiologie, Aix-en-Provence, (France)

    1996-05-01

    The Buffer/Container experiment was carried out for 2.5 years to examine the in-situ performance of compacted buffer material in a single emplacement borehole under vault-relevant conditions. During decommissioning of this experiment, numerous samples were taken for microbial analysis to determine if the naturally present microbial population in buffer material survived to conditions and to determine which groups of microorganisms would be dominant in such a simulated vault environment. Microbial analyses were initiated within 24 hour of sampling for all types of samples taken. The culture results showed an almost universal disappearance of viable microorganisms in the samples taken from near the heater surface. The microbial activity measurements confirmed the lack of viable organisms with very weak or no activity measured in most of these samples. Generally, aerobic heterotrophic culture conditions gave the highest mean colony-forming units (CFU) values at both 25 and 50 C. Under anaerobic conditions, and especially at 50 C, lower mean CFU values were obtained. In all samples analyzed, numbers of sulfate reducing bacteria were less than 1000 CFU/g dry material. Methanogens were either not present or were found in very low numbers. Anaerobic sulfur oxidizing bacteria were found in higher numbers in most sample types with sufficient moisture. The statistical evaluation of the culture data demonstrated clearly that the water content was the variable limiting the viability of the bacteria present, and not the temperature. 68 refs, 35 figs, 37 tabs.

  20. Physical Layer Network Coding

    DEFF Research Database (Denmark)

    Fukui, Hironori; Yomo, Hironori; Popovski, Petar

    2013-01-01

    of interfering nodes and usage of spatial reservation mechanisms. Specifically, we introduce a reserved area in order to protect the nodes involved in two-way relaying from the interference caused by neighboring nodes. We analytically derive the end-to-end rate achieved by PLNC considering the impact......Physical layer network coding (PLNC) has the potential to improve throughput of multi-hop networks. However, most of the works are focused on the simple, three-node model with two-way relaying, not taking into account the fact that there can be other neighboring nodes that can cause....../receive interference. The way to deal with this problem in distributed wireless networks is usage of MAC-layer mechanisms that make a spatial reservation of the shared wireless medium, similar to the well-known RTS/CTS in IEEE 802.11 wireless networks. In this paper, we investigate two-way relaying in presence...

  1. Concatenated quantum codes

    Energy Technology Data Exchange (ETDEWEB)

    Knill, E.; Laflamme, R.

    1996-07-01

    One main problem for the future of practial quantum computing is to stabilize the computation against unwanted interactions with the environment and imperfections in the applied operations. Existing proposals for quantum memories and quantum channels require gates with asymptotically zero error to store or transmit an input quantum state for arbitrarily long times or distances with fixed error. This report gives a method which has the property that to store or transmit a qubit with maximum error {epsilon} requires gates with errors at most {ital c}{epsilon} and storage or channel elements with error at most {epsilon}, independent of how long we wish to store the state or how far we wish to transmit it. The method relies on using concatenated quantum codes and hierarchically implemented recovery operations. The overhead of the method is polynomial in the time of storage or the distance of the transmission. Rigorous and heuristic lower bounds for the constant {ital c} are given.

  2. Code des baux 2018

    CERN Document Server

    Vial-Pedroletti, Béatrice; Kendérian, Fabien; Chavance, Emmanuelle; Coutan-Lapalus, Christelle

    2017-01-01

    Le code des baux 2018 vous offre un contenu extrêmement pratique, fiable et à jour au 1er août 2017. Cette 16e édition intègre notamment : le décret du 27 juillet 2017 relatif à l’évolution de certains loyers dans le cadre d’une nouvelle location ou d’un renouvellement de bail, pris en application de l’article 18 de la loi n° 89-462 du 6 juillet 1989 ; la loi du 27 janvier 2017 relative à l’égalité et à la citoyenneté ; la loi du 9 décembre 2016 relative à la transparence, à la lutte contre la corruption et à la modernisation de la vie économique ; la loi du 18 novembre 2016 de modernisation de la justice du xxie siècle

  3. GOC: General Orbit Code

    International Nuclear Information System (INIS)

    Maddox, L.B.; McNeilly, G.S.

    1979-08-01

    GOC (General Orbit Code) is a versatile program which will perform a variety of calculations relevant to isochronous cyclotron design studies. In addition to the usual calculations of interest (e.g., equilibrium and accelerated orbits, focusing frequencies, field isochronization, etc.), GOC has a number of options to calculate injections with a charge change. GOC provides both printed and plotted output, and will follow groups of particles to allow determination of finite-beam properties. An interactive PDP-10 program called GIP, which prepares input data for GOC, is available. GIP is a very easy and convenient way to prepare complicated input data for GOC. Enclosed with this report are several microfiche containing source listings of GOC and other related routines and the printed output from a multiple-option GOC run

  4. LDGM Codes for Channel Coding and Joint Source-Channel Coding of Correlated Sources

    Directory of Open Access Journals (Sweden)

    Javier Garcia-Frias

    2005-05-01

    Full Text Available We propose a coding scheme based on the use of systematic linear codes with low-density generator matrix (LDGM codes for channel coding and joint source-channel coding of multiterminal correlated binary sources. In both cases, the structures of the LDGM encoder and decoder are shown, and a concatenated scheme aimed at reducing the error floor is proposed. Several decoding possibilities are investigated, compared, and evaluated. For different types of noisy channels and correlation models, the resulting performance is very close to the theoretical limits.

  5. Surface acoustic wave coding for orthogonal frequency coded devices

    Science.gov (United States)

    Malocha, Donald (Inventor); Kozlovski, Nikolai (Inventor)

    2011-01-01

    Methods and systems for coding SAW OFC devices to mitigate code collisions in a wireless multi-tag system. Each device producing plural stepped frequencies as an OFC signal with a chip offset delay to increase code diversity. A method for assigning a different OCF to each device includes using a matrix based on the number of OFCs needed and the number chips per code, populating each matrix cell with OFC chip, and assigning the codes from the matrix to the devices. The asynchronous passive multi-tag system includes plural surface acoustic wave devices each producing a different OFC signal having the same number of chips and including a chip offset time delay, an algorithm for assigning OFCs to each device, and a transceiver to transmit an interrogation signal and receive OFC signals in response with minimal code collisions during transmission.

  6. Entanglement-assisted quantum MDS codes from negacyclic codes

    Science.gov (United States)

    Lu, Liangdong; Li, Ruihu; Guo, Luobin; Ma, Yuena; Liu, Yang

    2018-03-01

    The entanglement-assisted formalism generalizes the standard stabilizer formalism, which can transform arbitrary classical linear codes into entanglement-assisted quantum error-correcting codes (EAQECCs) by using pre-shared entanglement between the sender and the receiver. In this work, we construct six classes of q-ary entanglement-assisted quantum MDS (EAQMDS) codes based on classical negacyclic MDS codes by exploiting two or more pre-shared maximally entangled states. We show that two of these six classes q-ary EAQMDS have minimum distance more larger than q+1. Most of these q-ary EAQMDS codes are new in the sense that their parameters are not covered by the codes available in the literature.

  7. An algebraic approach to graph codes

    DEFF Research Database (Denmark)

    Pinero, Fernando

    This thesis consists of six chapters. The first chapter, contains a short introduction to coding theory in which we explain the coding theory concepts we use. In the second chapter, we present the required theory for evaluation codes and also give an example of some fundamental codes in coding...... theory as evaluation codes. Chapter three consists of the introduction to graph based codes, such as Tanner codes and graph codes. In Chapter four, we compute the dimension of some graph based codes with a result combining graph based codes and subfield subcodes. Moreover, some codes in chapter four...

  8. Diagonal Eigenvalue Unity (DEU) code for spectral amplitude coding-optical code division multiple access

    Science.gov (United States)

    Ahmed, Hassan Yousif; Nisar, K. S.

    2013-08-01

    Code with ideal in-phase cross correlation (CC) and practical code length to support high number of users are required in spectral amplitude coding-optical code division multiple access (SAC-OCDMA) systems. SAC systems are getting more attractive in the field of OCDMA because of its ability to eliminate the influence of multiple access interference (MAI) and also suppress the effect of phase induced intensity noise (PIIN). In this paper, we have proposed new Diagonal Eigenvalue Unity (DEU) code families with ideal in-phase CC based on Jordan block matrix with simple algebraic ways. Four sets of DEU code families based on the code weight W and number of users N for the combination (even, even), (even, odd), (odd, odd) and (odd, even) are constructed. This combination gives DEU code more flexibility in selection of code weight and number of users. These features made this code a compelling candidate for future optical communication systems. Numerical results show that the proposed DEU system outperforms reported codes. In addition, simulation results taken from a commercial optical systems simulator, Virtual Photonic Instrument (VPI™) shown that, using point to multipoint transmission in passive optical network (PON), DEU has better performance and could support long span with high data rate.

  9. Self-complementary circular codes in coding theory.

    Science.gov (United States)

    Fimmel, Elena; Michel, Christian J; Starman, Martin; Strüngmann, Lutz

    2018-04-01

    Self-complementary circular codes are involved in pairing genetic processes. A maximal [Formula: see text] self-complementary circular code X of trinucleotides was identified in genes of bacteria, archaea, eukaryotes, plasmids and viruses (Michel in Life 7(20):1-16 2017, J Theor Biol 380:156-177, 2015; Arquès and Michel in J Theor Biol 182:45-58 1996). In this paper, self-complementary circular codes are investigated using the graph theory approach recently formulated in Fimmel et al. (Philos Trans R Soc A 374:20150058, 2016). A directed graph [Formula: see text] associated with any code X mirrors the properties of the code. In the present paper, we demonstrate a necessary condition for the self-complementarity of an arbitrary code X in terms of the graph theory. The same condition has been proven to be sufficient for codes which are circular and of large size [Formula: see text] trinucleotides, in particular for maximal circular codes ([Formula: see text] trinucleotides). For codes of small-size [Formula: see text] trinucleotides, some very rare counterexamples have been constructed. Furthermore, the length and the structure of the longest paths in the graphs associated with the self-complementary circular codes are investigated. It has been proven that the longest paths in such graphs determine the reading frame for the self-complementary circular codes. By applying this result, the reading frame in any arbitrary sequence of trinucleotides is retrieved after at most 15 nucleotides, i.e., 5 consecutive trinucleotides, from the circular code X identified in genes. Thus, an X motif of a length of at least 15 nucleotides in an arbitrary sequence of trinucleotides (not necessarily all of them belonging to X) uniquely defines the reading (correct) frame, an important criterion for analyzing the X motifs in genes in the future.

  10. Error correcting coding for OTN

    DEFF Research Database (Denmark)

    Justesen, Jørn; Larsen, Knud J.; Pedersen, Lars A.

    2010-01-01

    Forward error correction codes for 100 Gb/s optical transmission are currently receiving much attention from transport network operators and technology providers. We discuss the performance of hard decision decoding using product type codes that cover a single OTN frame or a small number...... of such frames. In particular we argue that a three-error correcting BCH is the best choice for the component code in such systems....

  11. Numerical Tokamak Project code comparison

    International Nuclear Information System (INIS)

    Waltz, R.E.; Cohen, B.I.; Beer, M.A.

    1994-01-01

    The Numerical Tokamak Project undertook a code comparison using a set of TFTR tokamak parameters. Local radial annulus codes of both gyrokinetic and gyrofluid types were compared for both slab and toroidal case limits assuming ion temperature gradient mode turbulence in a pure plasma with adiabatic electrons. The heat diffusivities were found to be in good internal agreement within ± 50% of the group average over five codes

  12. Ethical codes in business practice

    OpenAIRE

    Kobrlová, Marie

    2013-01-01

    The diploma thesis discusses the issues of ethics and codes of ethics in business. The theoretical part defines basic concepts of ethics, presents its historical development and the methods and tools of business ethics. It also focuses on ethical codes and the area of law and ethics. The practical part consists of a quantitative survey, which provides views of selected business entities of business ethics and the use of codes of ethics in practice.

  13. QR code for medical information uses.

    Science.gov (United States)

    Fontelo, Paul; Liu, Fang; Ducut, Erick G

    2008-11-06

    We developed QR code online tools, simulated and tested QR code applications for medical information uses including scanning QR code labels, URLs and authentication. Our results show possible applications for QR code in medicine.

  14. High Order Modulation Protograph Codes

    Science.gov (United States)

    Nguyen, Thuy V. (Inventor); Nosratinia, Aria (Inventor); Divsalar, Dariush (Inventor)

    2014-01-01

    Digital communication coding methods for designing protograph-based bit-interleaved code modulation that is general and applies to any modulation. The general coding framework can support not only multiple rates but also adaptive modulation. The method is a two stage lifting approach. In the first stage, an original protograph is lifted to a slightly larger intermediate protograph. The intermediate protograph is then lifted via a circulant matrix to the expected codeword length to form a protograph-based low-density parity-check code.

  15. Semi-supervised sparse coding

    KAUST Repository

    Wang, Jim Jing-Yan; Gao, Xin

    2014-01-01

    Sparse coding approximates the data sample as a sparse linear combination of some basic codewords and uses the sparse codes as new presentations. In this paper, we investigate learning discriminative sparse codes by sparse coding in a semi-supervised manner, where only a few training samples are labeled. By using the manifold structure spanned by the data set of both labeled and unlabeled samples and the constraints provided by the labels of the labeled samples, we learn the variable class labels for all the samples. Furthermore, to improve the discriminative ability of the learned sparse codes, we assume that the class labels could be predicted from the sparse codes directly using a linear classifier. By solving the codebook, sparse codes, class labels and classifier parameters simultaneously in a unified objective function, we develop a semi-supervised sparse coding algorithm. Experiments on two real-world pattern recognition problems demonstrate the advantage of the proposed methods over supervised sparse coding methods on partially labeled data sets.

  16. Programming Entity Framework Code First

    CERN Document Server

    Lerman, Julia

    2011-01-01

    Take advantage of the Code First data modeling approach in ADO.NET Entity Framework, and learn how to build and configure a model based on existing classes in your business domain. With this concise book, you'll work hands-on with examples to learn how Code First can create an in-memory model and database by default, and how you can exert more control over the model through further configuration. Code First provides an alternative to the database first and model first approaches to the Entity Data Model. Learn the benefits of defining your model with code, whether you're working with an exis

  17. User manual of UNF code

    International Nuclear Information System (INIS)

    Zhang Jingshang

    2001-01-01

    The UNF code (2001 version) written in FORTRAN-90 is developed for calculating fast neutron reaction data of structure materials with incident energies from about 1 Kev up to 20 Mev. The code consists of the spherical optical model, the unified Hauser-Feshbach and exciton model. The man nal of the UNF code is available for users. The format of the input parameter files and the output files, as well as the functions of flag used in UNF code, are introduced in detail, and the examples of the format of input parameters files are given

  18. Semi-supervised sparse coding

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-07-06

    Sparse coding approximates the data sample as a sparse linear combination of some basic codewords and uses the sparse codes as new presentations. In this paper, we investigate learning discriminative sparse codes by sparse coding in a semi-supervised manner, where only a few training samples are labeled. By using the manifold structure spanned by the data set of both labeled and unlabeled samples and the constraints provided by the labels of the labeled samples, we learn the variable class labels for all the samples. Furthermore, to improve the discriminative ability of the learned sparse codes, we assume that the class labels could be predicted from the sparse codes directly using a linear classifier. By solving the codebook, sparse codes, class labels and classifier parameters simultaneously in a unified objective function, we develop a semi-supervised sparse coding algorithm. Experiments on two real-world pattern recognition problems demonstrate the advantage of the proposed methods over supervised sparse coding methods on partially labeled data sets.

  19. Consensus Convolutional Sparse Coding

    KAUST Repository

    Choudhury, Biswarup

    2017-12-01

    Convolutional sparse coding (CSC) is a promising direction for unsupervised learning in computer vision. In contrast to recent supervised methods, CSC allows for convolutional image representations to be learned that are equally useful for high-level vision tasks and low-level image reconstruction and can be applied to a wide range of tasks without problem-specific retraining. Due to their extreme memory requirements, however, existing CSC solvers have so far been limited to low-dimensional problems and datasets using a handful of low-resolution example images at a time. In this paper, we propose a new approach to solving CSC as a consensus optimization problem, which lifts these limitations. By learning CSC features from large-scale image datasets for the first time, we achieve significant quality improvements in a number of imaging tasks. Moreover, the proposed method enables new applications in high-dimensional feature learning that has been intractable using existing CSC methods. This is demonstrated for a variety of reconstruction problems across diverse problem domains, including 3D multispectral demosaicing and 4D light field view synthesis.

  20. Coded aperture tomography revisited

    International Nuclear Information System (INIS)

    Bizais, Y.; Rowe, R.W.; Zubal, I.G.; Bennett, G.W.; Brill, A.B.

    1983-01-01

    Coded aperture (CA) Tomography never achieved wide spread use in Nuclear Medicine, except for the degenerate case of Seven Pinhole tomagraphy (7PHT). However it enjoys several attractive features (high sensitivity and tomographic ability with a statis detector). On the other hand, resolution is usually poor especially along the depth axis and the reconstructed volume is rather limited. Arguments are presented justifying the position that CA tomography can be useful for imaging time-varying 3D structures, if its major drawbacks (poor longitudinal resolution and difficulty in quantification) are overcome. Poor results obtained with 7PHT can be explained by both a very limited angular range sampled and a crude modelling of the image formation process. Therefore improvements can be expected by the use of a dual-detector system, along with a better understanding of its sampling properties and the use of more powerful reconstruction algorithms. Non overlapping multipinhole plates, because they do not involve a decoding procedure, should be considered first for practical applications. Use of real CA should be considered for cases in which non overlapping multipinhole plates do not lead to satisfactory solutions. We have been and currently are carrying out theoretical and experimental works, in order to define the factors which limit CA imaging and to propose satisfactory solutions for Dynamic Emission Tomography

  1. Mobile code security

    Science.gov (United States)

    Ramalingam, Srikumar

    2001-11-01

    A highly secure mobile agent system is very important for a mobile computing environment. The security issues in mobile agent system comprise protecting mobile hosts from malicious agents, protecting agents from other malicious agents, protecting hosts from other malicious hosts and protecting agents from malicious hosts. Using traditional security mechanisms the first three security problems can be solved. Apart from using trusted hardware, very few approaches exist to protect mobile code from malicious hosts. Some of the approaches to solve this problem are the use of trusted computing, computing with encrypted function, steganography, cryptographic traces, Seal Calculas, etc. This paper focuses on the simulation of some of these existing techniques in the designed mobile language. Some new approaches to solve malicious network problem and agent tampering problem are developed using public key encryption system and steganographic concepts. The approaches are based on encrypting and hiding the partial solutions of the mobile agents. The partial results are stored and the address of the storage is destroyed as the agent moves from one host to another host. This allows only the originator to make use of the partial results. Through these approaches some of the existing problems are solved.

  2. Consensus Convolutional Sparse Coding

    KAUST Repository

    Choudhury, Biswarup

    2017-04-11

    Convolutional sparse coding (CSC) is a promising direction for unsupervised learning in computer vision. In contrast to recent supervised methods, CSC allows for convolutional image representations to be learned that are equally useful for high-level vision tasks and low-level image reconstruction and can be applied to a wide range of tasks without problem-specific retraining. Due to their extreme memory requirements, however, existing CSC solvers have so far been limited to low-dimensional problems and datasets using a handful of low-resolution example images at a time. In this paper, we propose a new approach to solving CSC as a consensus optimization problem, which lifts these limitations. By learning CSC features from large-scale image datasets for the first time, we achieve significant quality improvements in a number of imaging tasks. Moreover, the proposed method enables new applications in high dimensional feature learning that has been intractable using existing CSC methods. This is demonstrated for a variety of reconstruction problems across diverse problem domains, including 3D multispectral demosaickingand 4D light field view synthesis.

  3. Coding, cryptography and combinatorics

    CERN Document Server

    Niederreiter, Harald; Xing, Chaoping

    2004-01-01

    It has long been recognized that there are fascinating connections between cod­ ing theory, cryptology, and combinatorics. Therefore it seemed desirable to us to organize a conference that brings together experts from these three areas for a fruitful exchange of ideas. We decided on a venue in the Huang Shan (Yellow Mountain) region, one of the most scenic areas of China, so as to provide the additional inducement of an attractive location. The conference was planned for June 2003 with the official title Workshop on Coding, Cryptography and Combi­ natorics (CCC 2003). Those who are familiar with events in East Asia in the first half of 2003 can guess what happened in the end, namely the conference had to be cancelled in the interest of the health of the participants. The SARS epidemic posed too serious a threat. At the time of the cancellation, the organization of the conference was at an advanced stage: all invited speakers had been selected and all abstracts of contributed talks had been screened by the p...

  4. Consensus Convolutional Sparse Coding

    KAUST Repository

    Choudhury, Biswarup; Swanson, Robin; Heide, Felix; Wetzstein, Gordon; Heidrich, Wolfgang

    2017-01-01

    Convolutional sparse coding (CSC) is a promising direction for unsupervised learning in computer vision. In contrast to recent supervised methods, CSC allows for convolutional image representations to be learned that are equally useful for high-level vision tasks and low-level image reconstruction and can be applied to a wide range of tasks without problem-specific retraining. Due to their extreme memory requirements, however, existing CSC solvers have so far been limited to low-dimensional problems and datasets using a handful of low-resolution example images at a time. In this paper, we propose a new approach to solving CSC as a consensus optimization problem, which lifts these limitations. By learning CSC features from large-scale image datasets for the first time, we achieve significant quality improvements in a number of imaging tasks. Moreover, the proposed method enables new applications in high-dimensional feature learning that has been intractable using existing CSC methods. This is demonstrated for a variety of reconstruction problems across diverse problem domains, including 3D multispectral demosaicing and 4D light field view synthesis.

  5. Computer code abstract: NESTLE

    International Nuclear Information System (INIS)

    Turinsky, P.J.; Al-Chalabi, R.M.K.; Engrand, P.; Sarsour, H.N.; Faure, F.X.; Guo, W.

    1995-01-01

    NESTLE is a few-group neutron diffusion equation solver utilizing the nodal expansion method (NEM) for eigenvalue, adjoint, and fixed-source steady-state and transient problems. The NESTLE code solve the eigenvalue (criticality), eigenvalue adjoint, external fixed-source steady-state, and external fixed-source or eigenvalue initiated transient problems. The eigenvalue problem allows criticality searches to be completed, and the external fixed-source steady-state problem can search to achieve a specified power level. Transient problems model delayed neutrons via precursor groups. Several core properties can be input as time dependent. Two- or four-energy groups can be utilized, with all energy groups being thermal groups (i.e., upscatter exits) is desired. Core geometries modeled include Cartesian and hexagonal. Three-, two-, and one-dimensional models can be utilized with various symmetries. The thermal conditions predicted by the thermal-hydraulic model of the core are used to correct cross sections for temperature and density effects. Cross sections for temperature and density effects. Cross sections are parameterized by color, control rod state (i.e., in or out), and burnup, allowing fuel depletion to be modeled. Either a macroscopic or microscopic model may be employed

  6. Joint source-channel coding using variable length codes

    NARCIS (Netherlands)

    Balakirsky, V.B.

    2001-01-01

    We address the problem of joint source-channel coding when variable-length codes are used for information transmission over a discrete memoryless channel. Data transmitted over the channel are interpreted as pairs (m k ,t k ), where m k is a message generated by the source and t k is a time instant

  7. Interrelations of codes in human semiotic systems.

    OpenAIRE

    Somov, Georgij

    2016-01-01

    Codes can be viewed as mechanisms that enable relations of signs and their components, i.e., semiosis is actualized. The combinations of these relations produce new relations as new codes are building over other codes. Structures appear in the mechanisms of codes. Hence, codes can be described as transformations of structures from some material systems into others. Structures belong to different carriers, but exist in codes in their "pure" form. Building of codes over other codes fosters t...

  8. Further Generalisations of Twisted Gabidulin Codes

    DEFF Research Database (Denmark)

    Puchinger, Sven; Rosenkilde, Johan Sebastian Heesemann; Sheekey, John

    2017-01-01

    We present a new family of maximum rank distance (MRD) codes. The new class contains codes that are neither equivalent to a generalised Gabidulin nor to a twisted Gabidulin code, the only two known general constructions of linear MRD codes.......We present a new family of maximum rank distance (MRD) codes. The new class contains codes that are neither equivalent to a generalised Gabidulin nor to a twisted Gabidulin code, the only two known general constructions of linear MRD codes....

  9. MARS Code in Linux Environment

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Moon Kyu; Bae, Sung Won; Jung, Jae Joon; Chung, Bub Dong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    The two-phase system analysis code MARS has been incorporated into Linux system. The MARS code was originally developed based on the RELAP5/MOD3.2 and COBRA-TF. The 1-D module which evolved from RELAP5 alone could be applied for the whole NSSS system analysis. The 3-D module developed based on the COBRA-TF, however, could be applied for the analysis of the reactor core region where 3-D phenomena would be better treated. The MARS code also has several other code units that could be incorporated for more detailed analysis. The separate code units include containment analysis modules and 3-D kinetics module. These code modules could be optionally invoked to be coupled with the main MARS code. The containment code modules (CONTAIN and CONTEMPT), for example, could be utilized for the analysis of the plant containment phenomena in a coupled manner with the nuclear reactor system. The mass and energy interaction during the hypothetical coolant leakage accident could, thereby, be analyzed in a more realistic manner. In a similar way, 3-D kinetics could be incorporated for simulating the three dimensional reactor kinetic behavior, instead of using the built-in point kinetics model. The MARS code system, developed initially for the MS Windows environment, however, would not be adequate enough for the PC cluster system where multiple CPUs are available. When parallelism is to be eventually incorporated into the MARS code, MS Windows environment is not considered as an optimum platform. Linux environment, on the other hand, is generally being adopted as a preferred platform for the multiple codes executions as well as for the parallel application. In this study, MARS code has been modified for the adaptation of Linux platform. For the initial code modification, the Windows system specific features have been removed from the code. Since the coupling code module CONTAIN is originally in a form of dynamic load library (DLL) in the Windows system, a similar adaptation method

  10. Allele coding in genomic evaluation

    Directory of Open Access Journals (Sweden)

    Christensen Ole F

    2011-06-01

    Full Text Available Abstract Background Genomic data are used in animal breeding to assist genetic evaluation. Several models to estimate genomic breeding values have been studied. In general, two approaches have been used. One approach estimates the marker effects first and then, genomic breeding values are obtained by summing marker effects. In the second approach, genomic breeding values are estimated directly using an equivalent model with a genomic relationship matrix. Allele coding is the method chosen to assign values to the regression coefficients in the statistical model. A common allele coding is zero for the homozygous genotype of the first allele, one for the heterozygote, and two for the homozygous genotype for the other allele. Another common allele coding changes these regression coefficients by subtracting a value from each marker such that the mean of regression coefficients is zero within each marker. We call this centered allele coding. This study considered effects of different allele coding methods on inference. Both marker-based and equivalent models were considered, and restricted maximum likelihood and Bayesian methods were used in inference. Results Theoretical derivations showed that parameter estimates and estimated marker effects in marker-based models are the same irrespective of the allele coding, provided that the model has a fixed general mean. For the equivalent models, the same results hold, even though different allele coding methods lead to different genomic relationship matrices. Calculated genomic breeding values are independent of allele coding when the estimate of the general mean is included into the values. Reliabilities of estimated genomic breeding values calculated using elements of the inverse of the coefficient matrix depend on the allele coding because different allele coding methods imply different models. Finally, allele coding affects the mixing of Markov chain Monte Carlo algorithms, with the centered coding being

  11. MARS Code in Linux Environment

    International Nuclear Information System (INIS)

    Hwang, Moon Kyu; Bae, Sung Won; Jung, Jae Joon; Chung, Bub Dong

    2005-01-01

    The two-phase system analysis code MARS has been incorporated into Linux system. The MARS code was originally developed based on the RELAP5/MOD3.2 and COBRA-TF. The 1-D module which evolved from RELAP5 alone could be applied for the whole NSSS system analysis. The 3-D module developed based on the COBRA-TF, however, could be applied for the analysis of the reactor core region where 3-D phenomena would be better treated. The MARS code also has several other code units that could be incorporated for more detailed analysis. The separate code units include containment analysis modules and 3-D kinetics module. These code modules could be optionally invoked to be coupled with the main MARS code. The containment code modules (CONTAIN and CONTEMPT), for example, could be utilized for the analysis of the plant containment phenomena in a coupled manner with the nuclear reactor system. The mass and energy interaction during the hypothetical coolant leakage accident could, thereby, be analyzed in a more realistic manner. In a similar way, 3-D kinetics could be incorporated for simulating the three dimensional reactor kinetic behavior, instead of using the built-in point kinetics model. The MARS code system, developed initially for the MS Windows environment, however, would not be adequate enough for the PC cluster system where multiple CPUs are available. When parallelism is to be eventually incorporated into the MARS code, MS Windows environment is not considered as an optimum platform. Linux environment, on the other hand, is generally being adopted as a preferred platform for the multiple codes executions as well as for the parallel application. In this study, MARS code has been modified for the adaptation of Linux platform. For the initial code modification, the Windows system specific features have been removed from the code. Since the coupling code module CONTAIN is originally in a form of dynamic load library (DLL) in the Windows system, a similar adaptation method

  12. International standard problem (ISP) No. 41. Containment iodine computer code exercise based on a radioiodine test facility (RTF) experiment

    International Nuclear Information System (INIS)

    2000-04-01

    International Standard Problem (ISP) exercises are comparative exercises in which predictions of different computer codes for a given physical problem are compared with each other or with the results of a carefully controlled experimental study. The main goal of ISP exercises is to increase confidence in the validity and accuracy of the tools, which were used in assessing the safety of nuclear installations. Moreover, they enable code users to gain experience and demonstrate their competence. The ISP No. 41 exercise, computer code exercise based on a Radioiodine Test Facility (RTF) experiment on iodine behaviour in containment under severe accident conditions, is one of such ISP exercises. The ISP No. 41 exercise was borne at the recommendation at the Fourth Iodine Chemistry Workshop held at PSI, Switzerland in June 1996: 'the performance of an International Standard Problem as the basis of an in-depth comparison of the models as well as contributing to the database for validation of iodine codes'. [Proceedings NEA/CSNI/R(96)6, Summary and Conclusions NEA/CSNI/R(96)7]. COG (CANDU Owners Group), comprising AECL and the Canadian nuclear utilities, offered to make the results of a Radioiodine Test Facility (RTF) test available for such an exercise. The ISP No. 41 exercise was endorsed in turn by the FPC (PWG4's Task Group on Fission Product Phenomena in the Primary Circuit and the Containment), PWG4 (CSNI Principal Working Group on the Confinement of Accidental Radioactive Releases), and the CSNI. The OECD/NEA Committee on the Safety of Nuclear Installations (CSNI) has sponsored forty-five ISP exercises over the last twenty-four years, thirteen of them in the area of severe accidents. The criteria for the selection of the RTF test as a basis for the ISP-41 exercise were; (1) complementary to other RTF tests available through the PHEBUS and ACE programmes, (2) simplicity for ease of modelling and (3) good quality data. A simple RTF experiment performed under controlled

  13. Coding in pigeons: Multiple-coding versus single-code/default strategies.

    Science.gov (United States)

    Pinto, Carlos; Machado, Armando

    2015-05-01

    To investigate the coding strategies that pigeons may use in a temporal discrimination tasks, pigeons were trained on a matching-to-sample procedure with three sample durations (2s, 6s and 18s) and two comparisons (red and green hues). One comparison was correct following 2-s samples and the other was correct following both 6-s and 18-s samples. Tests were then run to contrast the predictions of two hypotheses concerning the pigeons' coding strategies, the multiple-coding and the single-code/default. According to the multiple-coding hypothesis, three response rules are acquired, one for each sample. According to the single-code/default hypothesis, only two response rules are acquired, one for the 2-s sample and a "default" rule for any other duration. In retention interval tests, pigeons preferred the "default" key, a result predicted by the single-code/default hypothesis. In no-sample tests, pigeons preferred the key associated with the 2-s sample, a result predicted by multiple-coding. Finally, in generalization tests, when the sample duration equaled 3.5s, the geometric mean of 2s and 6s, pigeons preferred the key associated with the 6-s and 18-s samples, a result predicted by the single-code/default hypothesis. The pattern of results suggests the need for models that take into account multiple sources of stimulus control. © Society for the Experimental Analysis of Behavior.

  14. Error-correction coding for digital communications

    Science.gov (United States)

    Clark, G. C., Jr.; Cain, J. B.

    This book is written for the design engineer who must build the coding and decoding equipment and for the communication system engineer who must incorporate this equipment into a system. It is also suitable as a senior-level or first-year graduate text for an introductory one-semester course in coding theory. Fundamental concepts of coding are discussed along with group codes, taking into account basic principles, practical constraints, performance computations, coding bounds, generalized parity check codes, polynomial codes, and important classes of group codes. Other topics explored are related to simple nonalgebraic decoding techniques for group codes, soft decision decoding of block codes, algebraic techniques for multiple error correction, the convolutional code structure and Viterbi decoding, syndrome decoding techniques, and sequential decoding techniques. System applications are also considered, giving attention to concatenated codes, coding for the white Gaussian noise channel, interleaver structures for coded systems, and coding for burst noise channels.

  15. Distributed space-time coding

    CERN Document Server

    Jing, Yindi

    2014-01-01

    Distributed Space-Time Coding (DSTC) is a cooperative relaying scheme that enables high reliability in wireless networks. This brief presents the basic concept of DSTC, its achievable performance, generalizations, code design, and differential use. Recent results on training design and channel estimation for DSTC and the performance of training-based DSTC are also discussed.

  16. NETWORK CODING BY BEAM FORMING

    DEFF Research Database (Denmark)

    2013-01-01

    Network coding by beam forming in networks, for example, in single frequency networks, can provide aid in increasing spectral efficiency. When network coding by beam forming and user cooperation are combined, spectral efficiency gains may be achieved. According to certain embodiments, a method...... cooperating with the plurality of user equipment to decode the received data....

  17. Building codes : obstacle or opportunity?

    Science.gov (United States)

    Alberto Goetzl; David B. McKeever

    1999-01-01

    Building codes are critically important in the use of wood products for construction. The codes contain regulations that are prescriptive or performance related for various kinds of buildings and construction types. A prescriptive standard might dictate that a particular type of material be used in a given application. A performance standard requires that a particular...

  18. Accelerator Physics Code Web Repository

    CERN Document Server

    Zimmermann, Frank; Bellodi, G; Benedetto, E; Dorda, U; Giovannozzi, Massimo; Papaphilippou, Y; Pieloni, T; Ruggiero, F; Rumolo, G; Schmidt, F; Todesco, E; Zotter, Bruno W; Payet, J; Bartolini, R; Farvacque, L; Sen, T; Chin, Y H; Ohmi, K; Oide, K; Furman, M; Qiang, J; Sabbi, G L; Seidl, P A; Vay, J L; Friedman, A; Grote, D P; Cousineau, S M; Danilov, V; Holmes, J A; Shishlo, A; Kim, E S; Cai, Y; Pivi, M; Kaltchev, D I; Abell, D T; Katsouleas, Thomas C; Boine-Frankenheim, O; Franchetti, G; Hofmann, I; Machida, S; Wei, J

    2006-01-01

    In the framework of the CARE HHH European Network, we have developed a web-based dynamic acceleratorphysics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.

  19. LFSC - Linac Feedback Simulation Code

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Valentin; /Fermilab

    2008-05-01

    The computer program LFSC (Code>) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100 Hz, as slower feedbacks, operating in the 0.1-1 Hz range in the Main Linac and Beam Delivery System. The code LFSC is running under Matlab for MS Windows operating system. It contains about 30,000 lines of source code in more than 260 subroutines. The code uses the LIAR ('Linear Accelerator Research code') for particle tracking under ground motion and technical noise perturbations. It uses the Guinea Pig code to simulate the luminosity performance. A set of input files includes the lattice description (XSIF format), and plane text files with numerical parameters, wake fields, ground motion data etc. The Matlab environment provides a flexible system for graphical output.

  20. Interleaver Design for Turbo Coding

    DEFF Research Database (Denmark)

    Andersen, Jakob Dahl; Zyablov, Viktor

    1997-01-01

    By a combination of construction and random search based on a careful analysis of the low weight words and the distance properties of the component codes, it is possible to find interleavers for turbo coding with a high minimum distance. We have designed a block interleaver with permutations...

  1. Code breaking in the pacific

    CERN Document Server

    Donovan, Peter

    2014-01-01

    Covers the historical context and the evolution of the technically complex Allied Signals Intelligence (Sigint) activity against Japan from 1920 to 1945 Describes, explains and analyzes the code breaking techniques developed during the war in the Pacific Exposes the blunders (in code construction and use) made by the Japanese Navy that led to significant US Naval victories

  2. Development status of TUF code

    International Nuclear Information System (INIS)

    Liu, W.S.; Tahir, A.; Zaltsgendler

    1996-01-01

    An overview of the important development of the TUF code in 1995 is presented. The development in the following areas is presented: control of round-off error propagation, gas resolution and release models, and condensation induced water hammer. This development is mainly generated from station requests for operational support and code improvement. (author)

  3. Accident consequence assessment code development

    International Nuclear Information System (INIS)

    Homma, T.; Togawa, O.

    1991-01-01

    This paper describes the new computer code system, OSCAAR developed for off-site consequence assessment of a potential nuclear accident. OSCAAR consists of several modules which have modeling capabilities in atmospheric transport, foodchain transport, dosimetry, emergency response and radiological health effects. The major modules of the consequence assessment code are described, highlighting the validation and verification of the models. (author)

  4. The nuclear codes and guidelines

    International Nuclear Information System (INIS)

    Sonter, M.

    1984-01-01

    This paper considers problems faced by the mining industry when implementing the nuclear codes of practice. Errors of interpretation are likely. A major criticism is that the guidelines to the codes must be seen as recommendations only. They are not regulations. Specific clauses in the guidelines are criticised

  5. Survey of coded aperture imaging

    International Nuclear Information System (INIS)

    Barrett, H.H.

    1975-01-01

    The basic principle and limitations of coded aperture imaging for x-ray and gamma cameras are discussed. Current trends include (1) use of time varying apertures, (2) use of ''dilute'' apertures with transmission much less than 50%, and (3) attempts to derive transverse tomographic sections, unblurred by other planes, from coded images

  6. ACCELERATION PHYSICS CODE WEB REPOSITORY.

    Energy Technology Data Exchange (ETDEWEB)

    WEI, J.

    2006-06-26

    In the framework of the CARE HHH European Network, we have developed a web-based dynamic accelerator-physics code repository. We describe the design, structure and contents of this repository, illustrate its usage, and discuss our future plans, with emphasis on code benchmarking.

  7. Grassmann codes and Schubert unions

    DEFF Research Database (Denmark)

    Hansen, Johan Peder; Johnsen, Trygve; Ranestad, Kristian

    2009-01-01

    We study subsets of Grassmann varieties over a field , such that these subsets are unions of Schubert cycles, with respect to a fixed flag. We study such sets in detail, and give applications to coding theory, in particular for Grassmann codes. For much is known about such Schubert unions with a ...

  8. On Network Coded Filesystem Shim

    DEFF Research Database (Denmark)

    Sørensen, Chres Wiant; Roetter, Daniel Enrique Lucani; Médard, Muriel

    2017-01-01

    Although network coding has shown the potential to revolutionize networking and storage, its deployment has faced a number of challenges. Usual proposals involve two approaches. First, deploying a new protocol (e.g., Multipath Coded TCP), or retrofitting another one (e.g., TCP/NC) to deliver bene...

  9. Running codes through the web

    International Nuclear Information System (INIS)

    Clark, R.E.H.

    2001-01-01

    Dr. Clark presented a report and demonstration of running atomic physics codes through the WWW. The atomic physics data is generated from Los Alamos National Laboratory (LANL) codes that calculate electron impact excitation, ionization, photoionization, and autoionization, and inversed processes through detailed balance. Samples of Web interfaces, input and output are given in the report

  10. Dynamic benchmarking of simulation codes

    International Nuclear Information System (INIS)

    Henry, R.E.; Paik, C.Y.; Hauser, G.M.

    1996-01-01

    Computer simulation of nuclear power plant response can be a full-scope control room simulator, an engineering simulator to represent the general behavior of the plant under normal and abnormal conditions, or the modeling of the plant response to conditions that would eventually lead to core damage. In any of these, the underlying foundation for their use in analysing situations, training of vendor/utility personnel, etc. is how well they represent what has been known from industrial experience, large integral experiments and separate effects tests. Typically, simulation codes are benchmarked with some of these; the level of agreement necessary being dependent upon the ultimate use of the simulation tool. However, these analytical models are computer codes, and as a result, the capabilities are continually enhanced, errors are corrected, new situations are imposed on the code that are outside of the original design basis, etc. Consequently, there is a continual need to assure that the benchmarks with important transients are preserved as the computer code evolves. Retention of this benchmarking capability is essential to develop trust in the computer code. Given the evolving world of computer codes, how is this retention of benchmarking capabilities accomplished? For the MAAP4 codes this capability is accomplished through a 'dynamic benchmarking' feature embedded in the source code. In particular, a set of dynamic benchmarks are included in the source code and these are exercised every time the archive codes are upgraded and distributed to the MAAP users. Three different types of dynamic benchmarks are used: plant transients; large integral experiments; and separate effects tests. Each of these is performed in a different manner. The first is accomplished by developing a parameter file for the plant modeled and an input deck to describe the sequence; i.e. the entire MAAP4 code is exercised. The pertinent plant data is included in the source code and the computer

  11. Distributed source coding of video

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Van Luong, Huynh

    2015-01-01

    A foundation for distributed source coding was established in the classic papers of Slepian-Wolf (SW) [1] and Wyner-Ziv (WZ) [2]. This has provided a starting point for work on Distributed Video Coding (DVC), which exploits the source statistics at the decoder side offering shifting processing...... steps, conventionally performed at the video encoder side, to the decoder side. Emerging applications such as wireless visual sensor networks and wireless video surveillance all require lightweight video encoding with high coding efficiency and error-resilience. The video data of DVC schemes differ from...... the assumptions of SW and WZ distributed coding, e.g. by being correlated in time and nonstationary. Improving the efficiency of DVC coding is challenging. This paper presents some selected techniques to address the DVC challenges. Focus is put on pin-pointing how the decoder steps are modified to provide...

  12. Non-Protein Coding RNAs

    CERN Document Server

    Walter, Nils G; Batey, Robert T

    2009-01-01

    This book assembles chapters from experts in the Biophysics of RNA to provide a broadly accessible snapshot of the current status of this rapidly expanding field. The 2006 Nobel Prize in Physiology or Medicine was awarded to the discoverers of RNA interference, highlighting just one example of a large number of non-protein coding RNAs. Because non-protein coding RNAs outnumber protein coding genes in mammals and other higher eukaryotes, it is now thought that the complexity of organisms is correlated with the fraction of their genome that encodes non-protein coding RNAs. Essential biological processes as diverse as cell differentiation, suppression of infecting viruses and parasitic transposons, higher-level organization of eukaryotic chromosomes, and gene expression itself are found to largely be directed by non-protein coding RNAs. The biophysical study of these RNAs employs X-ray crystallography, NMR, ensemble and single molecule fluorescence spectroscopy, optical tweezers, cryo-electron microscopy, and ot...

  13. Reliability-Based Code Calibration

    DEFF Research Database (Denmark)

    Faber, M.H.; Sørensen, John Dalsgaard

    2003-01-01

    The present paper addresses fundamental concepts of reliability based code calibration. First basic principles of structural reliability theory are introduced and it is shown how the results of FORM based reliability analysis may be related to partial safety factors and characteristic values....... Thereafter the code calibration problem is presented in its principal decision theoretical form and it is discussed how acceptable levels of failure probability (or target reliabilities) may be established. Furthermore suggested values for acceptable annual failure probabilities are given for ultimate...... and serviceability limit states. Finally the paper describes the Joint Committee on Structural Safety (JCSS) recommended procedure - CodeCal - for the practical implementation of reliability based code calibration of LRFD based design codes....

  14. What Froze the Genetic Code?

    Directory of Open Access Journals (Sweden)

    Lluís Ribas de Pouplana

    2017-04-01

    Full Text Available The frozen accident theory of the Genetic Code was a proposal by Francis Crick that attempted to explain the universal nature of the Genetic Code and the fact that it only contains information for twenty amino acids. Fifty years later, it is clear that variations to the universal Genetic Code exist in nature and that translation is not limited to twenty amino acids. However, given the astonishing diversity of life on earth, and the extended evolutionary time that has taken place since the emergence of the extant Genetic Code, the idea that the translation apparatus is for the most part immobile remains true. Here, we will offer a potential explanation to the reason why the code has remained mostly stable for over three billion years, and discuss some of the mechanisms that allow species to overcome the intrinsic functional limitations of the protein synthesis machinery.

  15. Verification of reactor safety codes

    International Nuclear Information System (INIS)

    Murley, T.E.

    1978-01-01

    The safety evaluation of nuclear power plants requires the investigation of wide range of potential accidents that could be postulated to occur. Many of these accidents deal with phenomena that are outside the range of normal engineering experience. Because of the expense and difficulty of full scale tests covering the complete range of accident conditions, it is necessary to rely on complex computer codes to assess these accidents. The central role that computer codes play in safety analyses requires that the codes be verified, or tested, by comparing the code predictions with a wide range of experimental data chosen to span the physical phenomena expected under potential accident conditions. This paper discusses the plans of the Nuclear Regulatory Commission for verifying the reactor safety codes being developed by NRC to assess the safety of light water reactors and fast breeder reactors. (author)

  16. What Froze the Genetic Code?

    Science.gov (United States)

    Ribas de Pouplana, Lluís; Torres, Adrian Gabriel; Rafels-Ybern, Àlbert

    2017-04-05

    The frozen accident theory of the Genetic Code was a proposal by Francis Crick that attempted to explain the universal nature of the Genetic Code and the fact that it only contains information for twenty amino acids. Fifty years later, it is clear that variations to the universal Genetic Code exist in nature and that translation is not limited to twenty amino acids. However, given the astonishing diversity of life on earth, and the extended evolutionary time that has taken place since the emergence of the extant Genetic Code, the idea that the translation apparatus is for the most part immobile remains true. Here, we will offer a potential explanation to the reason why the code has remained mostly stable for over three billion years, and discuss some of the mechanisms that allow species to overcome the intrinsic functional limitations of the protein synthesis machinery.

  17. Tristan code and its application

    Science.gov (United States)

    Nishikawa, K.-I.

    Since TRISTAN: The 3-D Electromagnetic Particle Code was introduced in 1990, it has been used for many applications including the simulations of global solar windmagnetosphere interaction. The most essential ingridients of this code have been published in the ISSS-4 book. In this abstract we describe some of issues and an application of this code for the study of global solar wind-magnetosphere interaction including a substorm study. The basic code (tristan.f) for the global simulation and a local simulation of reconnection with a Harris model (issrec2.f) are available at http:/www.physics.rutger.edu/˜kenichi. For beginners the code (isssrc2.f) with simpler boundary conditions is suitable to start to run simulations. The future of global particle simulations for a global geospace general circulation (GGCM) model with predictive capability (for Space Weather Program) is discussed.

  18. High efficiency video coding coding tools and specification

    CERN Document Server

    Wien, Mathias

    2015-01-01

    The video coding standard High Efficiency Video Coding (HEVC) targets at improved compression performance for video resolutions of HD and beyond, providing Ultra HD video at similar compressed bit rates as for HD video encoded with the well-established video coding standard H.264 | AVC. Based on known concepts, new coding structures and improved coding tools have been developed and specified in HEVC. The standard is expected to be taken up easily by established industry as well as new endeavors, answering the needs of todays connected and ever-evolving online world. This book presents the High Efficiency Video Coding standard and explains it in a clear and coherent language. It provides a comprehensive and consistently written description, all of a piece. The book targets at both, newbies to video coding as well as experts in the field. While providing sections with introductory text for the beginner, it suits as a well-arranged reference book for the expert. The book provides a comprehensive reference for th...

  19. Detecting non-coding selective pressure in coding regions

    Directory of Open Access Journals (Sweden)

    Blanchette Mathieu

    2007-02-01

    Full Text Available Abstract Background Comparative genomics approaches, where orthologous DNA regions are compared and inter-species conserved regions are identified, have proven extremely powerful for identifying non-coding regulatory regions located in intergenic or intronic regions. However, non-coding functional elements can also be located within coding region, as is common for exonic splicing enhancers, some transcription factor binding sites, and RNA secondary structure elements affecting mRNA stability, localization, or translation. Since these functional elements are located in regions that are themselves highly conserved because they are coding for a protein, they generally escaped detection by comparative genomics approaches. Results We introduce a comparative genomics approach for detecting non-coding functional elements located within coding regions. Codon evolution is modeled as a mixture of codon substitution models, where each component of the mixture describes the evolution of codons under a specific type of coding selective pressure. We show how to compute the posterior distribution of the entropy and parsimony scores under this null model of codon evolution. The method is applied to a set of growth hormone 1 orthologous mRNA sequences and a known exonic splicing elements is detected. The analysis of a set of CORTBP2 orthologous genes reveals a region of several hundred base pairs under strong non-coding selective pressure whose function remains unknown. Conclusion Non-coding functional elements, in particular those involved in post-transcriptional regulation, are likely to be much more prevalent than is currently known. With the numerous genome sequencing projects underway, comparative genomics approaches like that proposed here are likely to become increasingly powerful at detecting such elements.

  20. Coding for effective denial management.

    Science.gov (United States)

    Miller, Jackie; Lineberry, Joe

    2004-01-01

    Nearly everyone will agree that accurate and consistent coding of diagnoses and procedures is the cornerstone for operating a compliant practice. The CPT or HCPCS procedure code tells the payor what service was performed and also (in most cases) determines the amount of payment. The ICD-9-CM diagnosis code, on the other hand, tells the payor why the service was performed. If the diagnosis code does not meet the payor's criteria for medical necessity, all payment for the service will be denied. Implementation of an effective denial management program can help "stop the bleeding." Denial management is a comprehensive process that works in two ways. First, it evaluates the cause of denials and takes steps to prevent them. Second, denial management creates specific procedures for refiling or appealing claims that are initially denied. Accurate, consistent and compliant coding is key to both of these functions. The process of proactively managing claim denials also reveals a practice's administrative strengths and weaknesses, enabling radiology business managers to streamline processes, eliminate duplicated efforts and shift a larger proportion of the staff's focus from paperwork to servicing patients--all of which are sure to enhance operations and improve practice management and office morale. Accurate coding requires a program of ongoing training and education in both CPT and ICD-9-CM coding. Radiology business managers must make education a top priority for their coding staff. Front office staff, technologists and radiologists should also be familiar with the types of information needed for accurate coding. A good staff training program will also cover the proper use of Advance Beneficiary Notices (ABNs). Registration and coding staff should understand how to determine whether the patient's clinical history meets criteria for Medicare coverage, and how to administer an ABN if the exam is likely to be denied. Staff should also understand the restrictions on use of

  1. ESCADRE and ICARE code systems

    International Nuclear Information System (INIS)

    Reocreux, M.; Gauvain, J.

    1992-01-01

    The French sever accident code development program is following two parallel approaches: the first one is dealing with ''integral codes'' which are designed for giving immediate engineer answers, the second one is following a more mechanistic way in order to have the capability of detailed analysis of experiments, in order to get a better understanding of the scaling problem and reach a better confidence in plant calculations. In the first approach a complete system has been developed and is being used for practical cases: this is the ESCADRE system. In the second approach, a set of codes dealing first with primary circuit is being developed: a mechanistic core degradation code, ICARE, has been issued and is being coupled with the advanced thermalhydraulic code CATHARE. Fission product codes have been also coupled to CATHARE. The ''integral'' ESCADRE system and the mechanistic ICARE and associated codes are described. Their main characteristics are reviewed and the status of their development and assessment given. Future studies are finally discussed. 36 refs, 4 figs, 1 tab

  2. The ZPIC educational code suite

    Science.gov (United States)

    Calado, R.; Pardal, M.; Ninhos, P.; Helm, A.; Mori, W. B.; Decyk, V. K.; Vieira, J.; Silva, L. O.; Fonseca, R. A.

    2017-10-01

    Particle-in-Cell (PIC) codes are used in almost all areas of plasma physics, such as fusion energy research, plasma accelerators, space physics, ion propulsion, and plasma processing, and many other areas. In this work, we present the ZPIC educational code suite, a new initiative to foster training in plasma physics using computer simulations. Leveraging on our expertise and experience from the development and use of the OSIRIS PIC code, we have developed a suite of 1D/2D fully relativistic electromagnetic PIC codes, as well as 1D electrostatic. These codes are self-contained and require only a standard laptop/desktop computer with a C compiler to be run. The output files are written in a new file format called ZDF that can be easily read using the supplied routines in a number of languages, such as Python, and IDL. The code suite also includes a number of example problems that can be used to illustrate several textbook and advanced plasma mechanisms, including instructions for parameter space exploration. We also invite contributions to this repository of test problems that will be made freely available to the community provided the input files comply with the format defined by the ZPIC team. The code suite is freely available and hosted on GitHub at https://github.com/zambzamb/zpic. Work partially supported by PICKSC.

  3. Stability analysis by ERATO code

    International Nuclear Information System (INIS)

    Tsunematsu, Toshihide; Takeda, Tatsuoki; Matsuura, Toshihiko; Azumi, Masafumi; Kurita, Gen-ichi

    1979-12-01

    Problems in MHD stability calculations by ERATO code are described; which concern convergence property of results, equilibrium codes, and machine optimization of ERATO code. It is concluded that irregularity on a convergence curve is not due to a fault of the ERATO code itself but due to inappropriate choice of the equilibrium calculation meshes. Also described are a code to calculate an equilibrium as a quasi-inverse problem and a code to calculate an equilibrium as a result of a transport process. Optimization of the code with respect to I/O operations reduced both CPU time and I/O time considerably. With the FACOM230-75 APU/CPU multiprocessor system, the performance is about 6 times as high as with the FACOM230-75 CPU, showing the effectiveness of a vector processing computer for the kind of MHD computations. This report is a summary of the material presented at the ERATO workshop 1979(ORNL), supplemented with some details. (author)

  4. ETR/ITER systems code

    Energy Technology Data Exchange (ETDEWEB)

    Barr, W.L.; Bathke, C.G.; Brooks, J.N.; Bulmer, R.H.; Busigin, A.; DuBois, P.F.; Fenstermacher, M.E.; Fink, J.; Finn, P.A.; Galambos, J.D.; Gohar, Y.; Gorker, G.E.; Haines, J.R.; Hassanein, A.M.; Hicks, D.R.; Ho, S.K.; Kalsi, S.S.; Kalyanam, K.M.; Kerns, J.A.; Lee, J.D.; Miller, J.R.; Miller, R.L.; Myall, J.O.; Peng, Y-K.M.; Perkins, L.J.; Spampinato, P.T.; Strickler, D.J.; Thomson, S.L.; Wagner, C.E.; Willms, R.S.; Reid, R.L. (ed.)

    1988-04-01

    A tokamak systems code capable of modeling experimental test reactors has been developed and is described in this document. The code, named TETRA (for Tokamak Engineering Test Reactor Analysis), consists of a series of modules, each describing a tokamak system or component, controlled by an optimizer/driver. This code development was a national effort in that the modules were contributed by members of the fusion community and integrated into a code by the Fusion Engineering Design Center. The code has been checked out on the Cray computers at the National Magnetic Fusion Energy Computing Center and has satisfactorily simulated the Tokamak Ignition/Burn Experimental Reactor II (TIBER) design. A feature of this code is the ability to perform optimization studies through the use of a numerical software package, which iterates prescribed variables to satisfy a set of prescribed equations or constraints. This code will be used to perform sensitivity studies for the proposed International Thermonuclear Experimental Reactor (ITER). 22 figs., 29 tabs.

  5. ETR/ITER systems code

    International Nuclear Information System (INIS)

    Barr, W.L.; Bathke, C.G.; Brooks, J.N.

    1988-04-01

    A tokamak systems code capable of modeling experimental test reactors has been developed and is described in this document. The code, named TETRA (for Tokamak Engineering Test Reactor Analysis), consists of a series of modules, each describing a tokamak system or component, controlled by an optimizer/driver. This code development was a national effort in that the modules were contributed by members of the fusion community and integrated into a code by the Fusion Engineering Design Center. The code has been checked out on the Cray computers at the National Magnetic Fusion Energy Computing Center and has satisfactorily simulated the Tokamak Ignition/Burn Experimental Reactor II (TIBER) design. A feature of this code is the ability to perform optimization studies through the use of a numerical software package, which iterates prescribed variables to satisfy a set of prescribed equations or constraints. This code will be used to perform sensitivity studies for the proposed International Thermonuclear Experimental Reactor (ITER). 22 figs., 29 tabs

  6. LFSC - Linac Feedback Simulation Code

    International Nuclear Information System (INIS)

    Ivanov, Valentin; Fermilab

    2008-01-01

    The computer program LFSC ( ) is a numerical tool for simulation beam based feedback in high performance linacs. The code LFSC is based on the earlier version developed by a collective of authors at SLAC (L.Hendrickson, R. McEwen, T. Himel, H. Shoaee, S. Shah, P. Emma, P. Schultz) during 1990-2005. That code was successively used in simulation of SLC, TESLA, CLIC and NLC projects. It can simulate as pulse-to-pulse feedback on timescale corresponding to 5-100 Hz, as slower feedbacks, operating in the 0.1-1 Hz range in the Main Linac and Beam Delivery System. The code LFSC is running under Matlab for MS Windows operating system. It contains about 30,000 lines of source code in more than 260 subroutines. The code uses the LIAR ('Linear Accelerator Research code') for particle tracking under ground motion and technical noise perturbations. It uses the Guinea Pig code to simulate the luminosity performance. A set of input files includes the lattice description (XSIF format), and plane text files with numerical parameters, wake fields, ground motion data etc. The Matlab environment provides a flexible system for graphical output

  7. Coded communications with nonideal interleaving

    Science.gov (United States)

    Laufer, Shaul

    1991-02-01

    Burst error channels - a type of block interference channels - feature increasing capacity but decreasing cutoff rate as the memory rate increases. Despite the large capacity, there is degradation in the performance of practical coding schemes when the memory length is excessive. A short-coding error parameter (SCEP) was introduced, which expresses a bound on the average decoding-error probability for codes shorter than the block interference length. The performance of a coded slow frequency-hopping communication channel is analyzed for worst-case partial band jamming and nonideal interleaving, by deriving expressions for the capacity and cutoff rate. The capacity and cutoff rate, respectively, are shown to approach and depart from those of a memoryless channel corresponding to the transmission of a single code letter per hop. For multiaccess communications over a slot-synchronized collision channel without feedback, the channel was considered as a block interference channel with memory length equal to the number of letters transmitted in each slot. The effects of an asymmetrical background noise and a reduced collision error rate were studied, as aspects of real communications. The performance of specific convolutional and Reed-Solomon codes was examined for slow frequency-hopping systems with nonideal interleaving. An upper bound is presented for the performance of a Viterbi decoder for a convolutional code with nonideal interleaving, and a soft decision diversity combining technique is introduced.

  8. Coding and decoding for code division multiple user communication systems

    Science.gov (United States)

    Healy, T. J.

    1985-01-01

    A new algorithm is introduced which decodes code division multiple user communication signals. The algorithm makes use of the distinctive form or pattern of each signal to separate it from the composite signal created by the multiple users. Although the algorithm is presented in terms of frequency-hopped signals, the actual transmitter modulator can use any of the existing digital modulation techniques. The algorithm is applicable to error-free codes or to codes where controlled interference is permitted. It can be used when block synchronization is assumed, and in some cases when it is not. The paper also discusses briefly some of the codes which can be used in connection with the algorithm, and relates the algorithm to past studies which use other approaches to the same problem.

  9. GAMERA - The New Magnetospheric Code

    Science.gov (United States)

    Lyon, J.; Sorathia, K.; Zhang, B.; Merkin, V. G.; Wiltberger, M. J.; Daldorff, L. K. S.

    2017-12-01

    The Lyon-Fedder-Mobarry (LFM) code has been a main-line magnetospheric simulation code for 30 years. The code base, designed in the age of memory to memory vector ma- chines,is still in wide use for science production but needs upgrading to ensure the long term sustainability. In this presentation, we will discuss our recent efforts to update and improve that code base and also highlight some recent results. The new project GAM- ERA, Grid Agnostic MHD for Extended Research Applications, has kept the original design characteristics of the LFM and made significant improvements. The original de- sign included high order numerical differencing with very aggressive limiting, the ability to use arbitrary, but logically rectangular, grids, and maintenance of div B = 0 through the use of the Yee grid. Significant improvements include high-order upwinding and a non-clipping limiter. One other improvement with wider applicability is an im- proved averaging technique for the singularities in polar and spherical grids. The new code adopts a hybrid structure - multi-threaded OpenMP with an overarching MPI layer for large scale and coupled applications. The MPI layer uses a combination of standard MPI and the Global Array Toolkit from PNL to provide a lightweight mechanism for coupling codes together concurrently. The single processor code is highly efficient and can run magnetospheric simulations at the default CCMC resolution faster than real time on a MacBook pro. We have run the new code through the Athena suite of tests, and the results compare favorably with the codes available to the astrophysics community. LFM/GAMERA has been applied to many different situations ranging from the inner and outer heliosphere and magnetospheres of Venus, the Earth, Jupiter and Saturn. We present example results the Earth's magnetosphere including a coupled ring current (RCM), the magnetospheres of Jupiter and Saturn, and the inner heliosphere.

  10. SCALE Code System

    Energy Technology Data Exchange (ETDEWEB)

    Jessee, Matthew Anderson [ORNL

    2016-04-01

    The SCALE Code System is a widely-used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by the Reactor and Nuclear Systems Division (RNSD) of Oak Ridge National Laboratory (ORNL). SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor and lattice physics, radiation shielding, spent fuel and radioactive source term characterization, and sensitivity and uncertainty analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. SCALE provides an integrated framework with dozens of computational modules including three deterministic and three Monte Carlo radiation transport solvers that are selected based on the desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE includes unique capabilities for automated variance reduction for shielding calculations, as well as sensitivity and uncertainty analysis. SCALE’s graphical user interfaces assist with accurate system modeling, visualization of nuclear data, and convenient access to desired results.SCALE 6.2 provides many new capabilities and significant improvements of existing features.New capabilities include:• ENDF/B-VII.1 nuclear data libraries CE and MG with enhanced group structures,• Neutron covariance data based on ENDF/B-VII.1 and supplemented with ORNL data,• Covariance data for fission product yields and decay constants,• Stochastic uncertainty and correlation quantification for any SCALE sequence with Sampler,• Parallel calculations with KENO,• Problem-dependent temperature corrections for CE calculations,• CE shielding and criticality accident alarm system analysis with MAVRIC,• CE

  11. Code-Mixing and Code Switchingin The Process of Learning

    Directory of Open Access Journals (Sweden)

    Diyah Atiek Mustikawati

    2016-09-01

    Full Text Available This study aimed to describe a form of code switching and code mixing specific form found in the teaching and learning activities in the classroom as well as determining factors influencing events stand out that form of code switching and code mixing in question.Form of this research is descriptive qualitative case study which took place in Al Mawaddah Boarding School Ponorogo. Based on the analysis and discussion that has been stated in the previous chapter that the form of code mixing and code switching learning activities in Al Mawaddah Boarding School is in between the use of either language Java language, Arabic, English and Indonesian, on the use of insertion of words, phrases, idioms, use of nouns, adjectives, clauses, and sentences. Code mixing deciding factor in the learning process include: Identification of the role, the desire to explain and interpret, sourced from the original language and its variations, is sourced from a foreign language. While deciding factor in the learning process of code, includes: speakers (O1, partners speakers (O2, the presence of a third person (O3, the topic of conversation, evoke a sense of humour, and just prestige. The significance of this study is to allow readers to see the use of language in a multilingual society, especially in AL Mawaddah boarding school about the rules and characteristics variation in the language of teaching and learning activities in the classroom. Furthermore, the results of this research will provide input to the ustadz / ustadzah and students in developing oral communication skills and the effectiveness of teaching and learning strategies in boarding schools.

  12. Neural Decoder for Topological Codes

    Science.gov (United States)

    Torlai, Giacomo; Melko, Roger G.

    2017-07-01

    We present an algorithm for error correction in topological codes that exploits modern machine learning techniques. Our decoder is constructed from a stochastic neural network called a Boltzmann machine, of the type extensively used in deep learning. We provide a general prescription for the training of the network and a decoding strategy that is applicable to a wide variety of stabilizer codes with very little specialization. We demonstrate the neural decoder numerically on the well-known two-dimensional toric code with phase-flip errors.

  13. Coding chaotic billiards. Pt. 3

    International Nuclear Information System (INIS)

    Ullmo, D.; Giannoni, M.J.

    1993-01-01

    Non-tiling compact billiard defined on the pseudosphere is studied 'a la Morse coding'. As for most bounded systems, the coding is non exact. However, two sets of approximate grammar rules can be obtained, one specifying forbidden codes, and the other allowed ones. In-between some sequences remain in the 'unknown' zone, but their relative amount can be reduced to zero if one lets the length of the approximate grammar rules goes to infinity. The relationship between these approximate grammar rules and the 'pruning front' introduced by Cvitanovic et al. is discussed. (authors). 13 refs., 10 figs., 1 tab

  14. Iterative nonlinear unfolding code: TWOGO

    International Nuclear Information System (INIS)

    Hajnal, F.

    1981-03-01

    a new iterative unfolding code, TWOGO, was developed to analyze Bonner sphere neutron measurements. The code includes two different unfolding schemes which alternate on successive iterations. The iterative process can be terminated either when the ratio of the coefficient of variations in terms of the measured and calculated responses is unity, or when the percentage difference between the measured and evaluated sphere responses is less than the average measurement error. The code was extensively tested with various known spectra and real multisphere neutron measurements which were performed inside the containments of pressurized water reactors

  15. Atlas C++ Coding Standard Specification

    CERN Document Server

    Albrand, S; Barberis, D; Bosman, M; Jones, B; Stavrianakou, M; Arnault, C; Candlin, D; Candlin, R; Franck, E; Hansl-Kozanecka, Traudl; Malon, D; Qian, S; Quarrie, D; Schaffer, R D

    2001-01-01

    This document defines the ATLAS C++ coding standard, that should be adhered to when writing C++ code. It has been adapted from the original "PST Coding Standard" document (http://pst.cern.ch/HandBookWorkBook/Handbook/Programming/programming.html) CERN-UCO/1999/207. The "ATLAS standard" comprises modifications, further justification and examples for some of the rules in the original PST document. All changes were discussed in the ATLAS Offline Software Quality Control Group and feedback from the collaboration was taken into account in the "current" version.

  16. Writing the Live Coding Book

    DEFF Research Database (Denmark)

    Blackwell, Alan; Cox, Geoff; Lee, Sang Wong

    2016-01-01

    This paper is a speculation on the relationship between coding and writing, and the ways in which technical innovations and capabilities enable us to rethink each in terms of the other. As a case study, we draw on recent experiences of preparing a book on live coding, which integrates a wide range...... of personal, historical, technical and critical perspectives. This book project has been both experimental and reflective, in a manner that allows us to draw on critical understanding of both code and writing, and point to the potential for new practices in the future....

  17. LiveCode mobile development

    CERN Document Server

    Lavieri, Edward D

    2013-01-01

    A practical guide written in a tutorial-style, ""LiveCode Mobile Development Hotshot"" walks you step-by-step through 10 individual projects. Every project is divided into sub tasks to make learning more organized and easy to follow along with explanations, diagrams, screenshots, and downloadable material.This book is great for anyone who wants to develop mobile applications using LiveCode. You should be familiar with LiveCode and have access to a smartphone. You are not expected to know how to create graphics or audio clips.

  18. Network Coding Fundamentals and Applications

    CERN Document Server

    Medard, Muriel

    2011-01-01

    Network coding is a field of information and coding theory and is a method of attaining maximum information flow in a network. This book is an ideal introduction for the communications and network engineer, working in research and development, who needs an intuitive introduction to network coding and to the increased performance and reliability it offers in many applications. This book is an ideal introduction for the research and development communications and network engineer who needs an intuitive introduction to the theory and wishes to understand the increased performance and reliabil

  19. Linear network error correction coding

    CERN Document Server

    Guang, Xuan

    2014-01-01

    There are two main approaches in the theory of network error correction coding. In this SpringerBrief, the authors summarize some of the most important contributions following the classic approach, which represents messages by sequences?similar to algebraic coding,?and also briefly discuss the main results following the?other approach,?that uses the theory of rank metric codes for network error correction of representing messages by subspaces. This book starts by establishing the basic linear network error correction (LNEC) model and then characterizes two equivalent descriptions. Distances an

  20. Tree Coding of Bilevel Images

    DEFF Research Database (Denmark)

    Martins, Bo; Forchhammer, Søren

    1998-01-01

    Presently, sequential tree coders are the best general purpose bilevel image coders and the best coders of halftoned images. The current ISO standard, Joint Bilevel Image Experts Group (JBIG), is a good example. A sequential tree coder encodes the data by feeding estimates of conditional...... is one order of magnitude slower than JBIG, obtains excellent and highly robust compression performance. A multipass free tree coding scheme produces superior compression results for all test images. A multipass free template coding scheme produces significantly better results than JBIG for difficult...... images such as halftones. By utilizing randomized subsampling in the template selection, the speed becomes acceptable for practical image coding...

  1. Studies on DANESS Code Modeling

    International Nuclear Information System (INIS)

    Jeong, Chang Joon

    2009-09-01

    The DANESS code modeling study has been performed. DANESS code is widely used in a dynamic fuel cycle analysis. Korea Atomic Energy Research Institute (KAERI) has used the DANESS code for the Korean national nuclear fuel cycle scenario analysis. In this report, the important models such as Energy-demand scenario model, New Reactor Capacity Decision Model, Reactor and Fuel Cycle Facility History Model, and Fuel Cycle Model are investigated. And, some models in the interface module are refined and inserted for Korean nuclear fuel cycle model. Some application studies have also been performed for GNEP cases and for US fast reactor scenarios with various conversion ratios

  2. Beam-dynamics codes used at DARHT

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Jr., Carl August [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-01

    Several beam simulation codes are used to help gain a better understanding of beam dynamics in the DARHT LIAs. The most notable of these fall into the following categories: for beam production – Tricomp Trak orbit tracking code, LSP Particle in cell (PIC) code, for beam transport and acceleration – XTR static envelope and centroid code, LAMDA time-resolved envelope and centroid code, LSP-Slice PIC code, for coasting-beam transport to target – LAMDA time-resolved envelope code, LSP-Slice PIC code. These codes are also being used to inform the design of Scorpius.

  3. Introduction to coding and information theory

    CERN Document Server

    Roman, Steven

    1997-01-01

    This book is intended to introduce coding theory and information theory to undergraduate students of mathematics and computer science. It begins with a review of probablity theory as applied to finite sample spaces and a general introduction to the nature and types of codes. The two subsequent chapters discuss information theory: efficiency of codes, the entropy of information sources, and Shannon's Noiseless Coding Theorem. The remaining three chapters deal with coding theory: communication channels, decoding in the presence of errors, the general theory of linear codes, and such specific codes as Hamming codes, the simplex codes, and many others.

  4. Allegheny County Zip Code Boundaries

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset demarcates the zip code boundaries that lie within Allegheny County.If viewing this description on the Western Pennsylvania Regional Data Center’s open...

  5. Ultrasound imaging using coded signals

    DEFF Research Database (Denmark)

    Misaridis, Athanasios

    Modulated (or coded) excitation signals can potentially improve the quality and increase the frame rate in medical ultrasound scanners. The aim of this dissertation is to investigate systematically the applicability of modulated signals in medical ultrasound imaging and to suggest appropriate...... methods for coded imaging, with the goal of making better anatomic and flow images and three-dimensional images. On the first stage, it investigates techniques for doing high-resolution coded imaging with improved signal-to-noise ratio compared to conventional imaging. Subsequently it investigates how...... coded excitation can be used for increasing the frame rate. The work includes both simulated results using Field II, and experimental results based on measurements on phantoms as well as clinical images. Initially a mathematical foundation of signal modulation is given. Pulse compression based...

  6. National Tribal Building Codes Summit

    Science.gov (United States)

    National Tribal Building Codes summit statement developed to support tribes interested in adopting green and culturally-appropriate building systems to ensure safe, sustainable, affordable, and culturally-appropriate buildings on tribal lands.

  7. Tracking Code for Microwave Instability

    International Nuclear Information System (INIS)

    Heifets, S.; SLAC

    2006-01-01

    To study microwave instability the tracking code is developed. For bench marking, results are compared with Oide-Yokoya results [1] for broad-band Q = 1 impedance. Results hint to two possible mechanisms determining the threshold of instability

  8. CRUCIB: an axisymmetric convection code

    International Nuclear Information System (INIS)

    Bertram, L.A.

    1975-03-01

    The CRUCIB code was written in support of an experimental program aimed at measurement of thermal diffusivities of refractory liquids. Precise values of diffusivity are necessary to realistic analysis of reactor safety problems, nuclear waste disposal procedures, and fundamental metal forming processes. The code calculates the axisymmetric transient convective motions produced in a right circular cylindrical crucible, which is surface heated by an annular heat pulse. Emphasis of this report is placed on the input-output options of the CRUCIB code, which are tailored to assess the importance of the convective heat transfer in determining the surface temperature distribution. Use is limited to Prandtl numbers less than unity; larger values can be accommodated by replacement of a single block of the code, if desired. (U.S.)

  9. QUIL: a chemical equilibrium code

    International Nuclear Information System (INIS)

    Lunsford, J.L.

    1977-02-01

    A chemical equilibrium code QUIL is described, along with two support codes FENG and SURF. QUIL is designed to allow calculations on a wide range of chemical environments, which may include surface phases. QUIL was written specifically to calculate distributions associated with complex equilibria involving fission products in the primary coolant loop of the high-temperature gas-cooled reactor. QUIL depends upon an energy-data library called ELIB. This library is maintained by FENG and SURF. FENG enters into the library all reactions having standard free energies of reaction that are independent of concentration. SURF enters all surface reactions into ELIB. All three codes are interactive codes written to be used from a remote terminal, with paging control provided. Plotted output is also available

  10. Electronic Code of Federal Regulations

    Data.gov (United States)

    National Archives and Records Administration — The Electronic Code of Federal Regulations (e-CFR) is the codification of the general and permanent rules published in the Federal Register by the executive...

  11. Zip Codes - MDC_WCSZipcode

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — The WCSZipcode polygon feature class was created by Miami-Dade Enterprise Technology Department to be used in the WCS batch jobs to assign the actual zip code of...

  12. The intercomparison of aerosol codes

    International Nuclear Information System (INIS)

    Dunbar, I.H.; Fermandjian, J.; Gauvain, J.

    1988-01-01

    The behavior of aerosols in a reactor containment vessel following a severe accident could be an important determinant of the accident source term to the environment. Various processes result in the deposition of the aerosol onto surfaces within the containment, from where they are much less likely to be released. Some of these processes are very sensitive to particle size, so it is important to model the aerosol growth processes: agglomeration and condensation. A number of computer codes have been written to model growth and deposition processes. They have been tested against each other in a series of code comparison exercises. These exercises have investigated sensitivities to physical and numerical assumptions and have also proved a useful means of quality control for the codes. Various exercises in which code predictions are compared with experimental results are now under way

  13. Automatic code generation in practice

    DEFF Research Database (Denmark)

    Adam, Marian Sorin; Kuhrmann, Marco; Schultz, Ulrik Pagh

    2016-01-01

    -specific language to specify those requirements and to allow for generating a safety-enforcing layer of code, which is deployed to the robot. The paper at hand reports experiences in practically applying code generation to mobile robots. For two cases, we discuss how we addressed challenges, e.g., regarding weaving......Mobile robots often use a distributed architecture in which software components are deployed to heterogeneous hardware modules. Ensuring the consistency with the designed architecture is a complex task, notably if functional safety requirements have to be fulfilled. We propose to use a domain...... code generation into proprietary development environments and testing of manually written code. We find that a DSL based on the same conceptual model can be used across different kinds of hardware modules, but a significant adaptation effort is required in practical scenarios involving different kinds...

  14. Squares of Random Linear Codes

    DEFF Research Database (Denmark)

    Cascudo Pueyo, Ignacio; Cramer, Ronald; Mirandola, Diego

    2015-01-01

    a positive answer, for codes of dimension $k$ and length roughly $\\frac{1}{2}k^2$ or smaller. Moreover, the convergence speed is exponential if the difference $k(k+1)/2-n$ is at least linear in $k$. The proof uses random coding and combinatorial arguments, together with algebraic tools involving the precise......Given a linear code $C$, one can define the $d$-th power of $C$ as the span of all componentwise products of $d$ elements of $C$. A power of $C$ may quickly fill the whole space. Our purpose is to answer the following question: does the square of a code ``typically'' fill the whole space? We give...

  15. Cost reducing code implementation strategies

    International Nuclear Information System (INIS)

    Kurtz, Randall L.; Griswold, Michael E.; Jones, Gary C.; Daley, Thomas J.

    1995-01-01

    Sargent and Lundy's Code consulting experience reveals a wide variety of approaches toward implementing the requirements of various nuclear Codes Standards. This paper will describe various Code implementation strategies which assure that Code requirements are fully met in a practical and cost-effective manner. Applications to be discussed includes the following: new construction; repair, replacement and modifications; assessments and life extensions. Lessons learned and illustrative examples will be included. Preferred strategies and specific recommendations will also be addressed. Sargent and Lundy appreciates the opportunity provided by the Korea Atomic Industrial Forum and Korean Nuclear Society to share our ideas and enhance global cooperation through the exchange of information and views on relevant topics

  16. Adaptive decoding of convolutional codes

    Directory of Open Access Journals (Sweden)

    K. Hueske

    2007-06-01

    Full Text Available Convolutional codes, which are frequently used as error correction codes in digital transmission systems, are generally decoded using the Viterbi Decoder. On the one hand the Viterbi Decoder is an optimum maximum likelihood decoder, i.e. the most probable transmitted code sequence is obtained. On the other hand the mathematical complexity of the algorithm only depends on the used code, not on the number of transmission errors. To reduce the complexity of the decoding process for good transmission conditions, an alternative syndrome based decoder is presented. The reduction of complexity is realized by two different approaches, the syndrome zero sequence deactivation and the path metric equalization. The two approaches enable an easy adaptation of the decoding complexity for different transmission conditions, which results in a trade-off between decoding complexity and error correction performance.

  17. Covariance data processing code. ERRORJ

    International Nuclear Information System (INIS)

    Kosako, Kazuaki

    2001-01-01

    The covariance data processing code, ERRORJ, was developed to process the covariance data of JENDL-3.2. ERRORJ has the processing functions of covariance data for cross sections including resonance parameters, angular distribution and energy distribution. (author)

  18. Multimedia signal coding and transmission

    CERN Document Server

    Ohm, Jens-Rainer

    2015-01-01

    This textbook covers the theoretical background of one- and multidimensional signal processing, statistical analysis and modelling, coding and information theory with regard to the principles and design of image, video and audio compression systems. The theoretical concepts are augmented by practical examples of algorithms for multimedia signal coding technology, and related transmission aspects. On this basis, principles behind multimedia coding standards, including most recent developments like High Efficiency Video Coding, can be well understood. Furthermore, potential advances in future development are pointed out. Numerous figures and examples help to illustrate the concepts covered. The book was developed on the basis of a graduate-level university course, and most chapters are supplemented by exercises. The book is also a self-contained introduction both for researchers and developers of multimedia compression systems in industry.

  19. NESTLE: A nodal kinetics code

    International Nuclear Information System (INIS)

    Al-Chalabi, R.M.; Turinsky, P.J.; Faure, F.-X.; Sarsour, H.N.; Engrand, P.R.

    1993-01-01

    The NESTLE nodal kinetics code has been developed for utilization as a stand-alone code for steady-state and transient reactor neutronic analysis and for incorporation into system transient codes, such as TRAC and RELAP. The latter is desirable to increase the simulation fidelity over that obtained from currently employed zero- and one-dimensional neutronic models and now feasible due to advances in computer performance and efficiency of nodal methods. As a stand-alone code, requirements are that it operate on a range of computing platforms from memory-limited personal computers (PCs) to supercomputers with vector processors. This paper summarizes the features of NESTLE that reflect the utilization and requirements just noted

  20. Description of the COMRADEX code

    International Nuclear Information System (INIS)

    Spangler, G.W.; Boling, M.; Rhoades, W.A.; Willis, C.A.

    1967-01-01

    The COMRADEX Code is discussed briefly and instructions are provided for the use of the code. The subject code was developed for calculating doses from hypothetical power reactor accidents. It permits the user to analyze four successive levels of containment with time-varying leak rates. Filtration, cleanup, fallout and plateout in each containment shell can also be analyzed. The doses calculated include the direct gamma dose from the containment building, the internal doses to as many as 14 organs including the thyroid, bone, lung, etc. from inhaling the contaminated air, and the external gamma doses from the cloud. While further improvements are needed, such as a provision for calculating doses from fallout, rainout and washout, the present code capabilities have a wide range of applicability for reactor accident analysis