WorldWideScience

Sample records for source term development

  1. Development of source term PIRT of Fukushima Daiichi NPPs accident

    International Nuclear Information System (INIS)

    Suehiro, S.; Okamoto, K.

    2017-01-01

    The severe accident evaluation committee of AESJ (Atomic Energy Society of Japan) developed the thermal hydraulic PIRT (Phenomena Identification and Ranking Table) and the source term PIRT based on findings during the Fukushima Daiichi NPPs accident. These PIRTs aimed to explore the debris distribution and the current condition in the NPPs with high accuracy and to extract higher priority from the aspect of the sophistication of the analytical technology to predict the severe accident phenomena by the code. The source term PIRT was divided into 3 phases for the time domain and 9 categories for the spatial domain. The 68 phenomena were extracted and the importance from viewpoint of the source term was ranked through brainstorming and discussion. This paper describes the developed source term PIRT list and summarized the high ranked phenomena in each phase. (author)

  2. EDF source term reduction project main outcomes and further developments

    International Nuclear Information System (INIS)

    Ranchoux, Gilles; Bonnefon, Julien; Benfarah, Moez; Wintergerst Matthieu; Gressier, Frederic; Leclercq, Stephanie

    2012-09-01

    The dose reduction is a strategic purpose for EDF in link with the stakes of, nuclear acceptability, respect of regulation and productivity gains. This consists not only in improving the reactor shutdown organization (time spent in control area, biological shielding,...) but also in improving the radiological state of the unit and the efficiency of the source term reduction operations. Since 2003, EDF has been running an innovative project called 'Source Term Reduction' federating the different EDF research and engineering centers in order to: - participate to the long term view about Radiological Protection issues (international feedback analyses), - develop contamination prediction tools (OSCAR software) suitable for the industrial needs (operating units and EPR design), - develop scientific models useful for the understanding of contamination mechanisms to support the strategic decision processes, - carry on with updating and analyzing of contamination measurements feedback in corrosion products (EMECC and CZT campaigns), - carry on with the operational support at short or middle term by optimizing startup and shutdown processes, pre-oxidation or and by improving purification efficiency or material characteristics. This paper will show in a first part the main 2011 results in occupational exposure (collective and individual dose, RCS index...). In a second part, an overview of the main EDF outcomes of the last 3 years in the field of source term reduction will be presented. Future developments extended to contamination issues in EDF NPPs will be also pointed out in this paper. (authors)

  3. Perspectives on source terms based on early research and development

    International Nuclear Information System (INIS)

    Pressesky, A.J.

    1985-07-01

    This report presents an overview of the key documentation of the research and development programs relevant to the source term issue which were undertaken by the Atomic Energy Commission between 1950 and 1970. The source term is taken to be the amount, composition (physical and chemical), and timing of the projected release of radioactivity to the environment in the hypothetical event of a severe reactor accident in a light water reactor of the type currently being licensed, built and operated. The objective is to illuminate and provide perspectives on (a) the maturity of the technical data base and the analytical methodology, (b) the extent to which remaining conservatisms can be applied to compensate for uncertainties, (c) the purpose for which the technology and methodology will be used, and (d) the need to keep problems and uncertainties in proper perspective. Comments that can provide some context for the difficult programmatic choices to be made are included, and technical considerations that may be inadequately applied or neglected in some current source term calculations were studied. This review has not uncovered any significant technical considerations that have been omitted or are being inadequately treated in current source term analyses, except perhaps the contribution made to in-containment aerosols by coolant comminution upon escape at pressure from the reactor coolant system. 11 refs

  4. Development of in-vessel source term analysis code, tracer

    International Nuclear Information System (INIS)

    Miyagi, K.; Miyahara, S.

    1996-01-01

    Analyses of radionuclide transport in fuel failure accidents (generally referred to source terms) are considered to be important especially in the severe accident evaluation. The TRACER code has been developed to realistically predict the time dependent behavior of FPs and aerosols within the primary cooling system for wide range of fuel failure events. This paper presents the model description, results of validation study, the recent model advancement status of the code, and results of check out calculations under reactor conditions. (author)

  5. Development of Reference Source Terms for EU-APR1400

    Energy Technology Data Exchange (ETDEWEB)

    Kim, ByungIl; Lee, Chonghui; Lee, Dongsu; Ko, Heejin; Kang, Sangho [KEPCO Engineering and Construction Co. Inc., Yongin (Korea, Republic of)

    2014-05-15

    These source terms are developed for the typical U. S. NPP and do not reflect the design characteristics of EU-APR1400 (1,400 MWe PWR) which will be applied for the EUR certification in European countries. The process of developing the RST for EU-APR1400 is to undergo a similar process that NUREG-1465 had gone through when it came out with its proposed source terms. The purpose of this study is to develop the EU-APR1400 design-specific RST complied with the EUR. The Large LOCA is the reference equence used in the NUREG-1465 evaluation, whereas the EUAPR1400 risk-significant sequences are dominated by small LOCA and non-LOCA sequences. Moreover, when considering the EU-APR1400 has many design features to mitigate the consequences of severe accident phenomena, it is not surprising that the aspects of both release fractions and durations are distinctly different from NUREG-1465. This RST will be continuously updated to reflect to the design features of EU-APR1400, and then, be used as the reference for design purposes such as criteria satisfaction of radioactivity releases, equipment survivability, control room habitability for severe accident, and so on.

  6. Source term development for tritium at the Sheffield disposal site

    International Nuclear Information System (INIS)

    MacKenzie, D.R.; Barletta, R.E.; Smalley, J.F.; Kempf, C.R.; Davis, R.E.

    1984-01-01

    The Sheffield low-level radioactive waste disposal site, which ceased operation in 1978, has been the focus of modeling efforts by the NRC for the purpose of predicting long-term site behavior. To provide the NRC with the information required for its modeling effort, a study to define the source term for tritium in eight trenches at the Sheffield site has been undertaken. Tritium is of special interest since significant concentrations of the isotope have been found in groundwater samples taken at the site and at locations outside the site boundary. Previous estimates of tritium site inventory at Sheffield are in wide disagreement. In this study, the tritium inventory in the eight trenches was estimated by reviewing the radioactive shipping records (RSRs) for waste buried in these trenches. It has been found that the tritium shipped for burial at the site was probably higher than previously estimated. In the eight trenches surveyed, which amount to roughly one half the total volume and activity buried at Sheffield, approximately 2350 Ci of tritium from non-fuel cycle sources were identified. The review of RSRs also formed the basis for obtaining waste package descriptions and for contacting large waste generators to obtain more detailed information regarding these waste packages. As a result of this review and the selected generator contacts, the non-fuel cycle tritium waste was categorized. The tritium releases from each of these waste categories were modeled. The results of this modeling effort are presented for each of the eight trenches selected. 3 references, 2 figures

  7. Regulatory Technology Development Plan Sodium Fast Reactor. Mechanistic Source Term Development

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David S. [Argonne National Lab. (ANL), Argonne, IL (United States); Brunett, Acacia Joann [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, Matthew D. [Argonne National Lab. (ANL), Argonne, IL (United States); Sienicki, James J. [Argonne National Lab. (ANL), Argonne, IL (United States); Sofu, Tanju [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-02-28

    Construction and operation of a nuclear power installation in the U.S. requires licensing by the U.S. Nuclear Regulatory Commission (NRC). A vital part of this licensing process and integrated safety assessment entails the analysis of a source term (or source terms) that represents the release of radionuclides during normal operation and accident sequences. Historically, nuclear plant source term analyses have utilized deterministic, bounding assessments of the radionuclides released to the environment. Significant advancements in technical capabilities and the knowledge state have enabled the development of more realistic analyses such that a mechanistic source term (MST) assessment is now expected to be a requirement of advanced reactor licensing. This report focuses on the state of development of an MST for a sodium fast reactor (SFR), with the intent of aiding in the process of MST definition by qualitatively identifying and characterizing the major sources and transport processes of radionuclides. Due to common design characteristics among current U.S. SFR vendor designs, a metal-fuel, pool-type SFR has been selected as the reference design for this work, with all phenomenological discussions geared toward this specific reactor configuration. This works also aims to identify the key gaps and uncertainties in the current knowledge state that must be addressed for SFR MST development. It is anticipated that this knowledge state assessment can enable the coordination of technology and analysis tool development discussions such that any knowledge gaps may be addressed. Sources of radionuclides considered in this report include releases originating both in-vessel and ex-vessel, including in-core fuel, primary sodium and cover gas cleanup systems, and spent fuel movement and handling. Transport phenomena affecting various release groups are identified and qualitatively discussed, including fuel pin and primary coolant retention, and behavior in the cover gas and

  8. Development of source term evaluation method for Korean Next Generation Reactor(III)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Geon Jae; Park, Jin Baek; Lee, Yeong Il; Song, Min Cheonl; Lee, Ho Jin [Korea Advanced Institue of Science and Technology, Taejon (Korea, Republic of)

    1998-06-15

    This project had investigated irradiation characteristics of MOX fuel method to predict nuclide concentration at primary and secondary coolant using a core containing 100% of all MOX fuel and development of source term evaluation tool. In this study, several prediction methods of source term are evaluated. Detailed contents of this project are : an evaluation of model for nuclear concentration at Reactor Coolant System, evaluation of primary and secondary coolant concentration of reference Nuclear Power Plant using purely MOX fuel, suggestion of source term prediction method of NPP with a core using MOX fuel.

  9. Analysis of safety information for nuclear power plants and development of source term estimation program

    International Nuclear Information System (INIS)

    Kim, Tae Woon; Choi, Seong Soo; Park, Jin Hee

    1999-12-01

    Current CARE(Computerized Advisory System for Radiological Emergency) in KINS(Korea Institute of Nuclear Safety) has no STES(Source Term Estimation System) which links between SIDS(Safety Information Display System) and FADAS(Following Accident Dose Assessment System). So in this study, STES is under development. STES system is the system that estimates the source term based on the safety information provided by SIDS. Estimated source term is given to FADAS as an input for estimation of environmental effect of radiation. Through this first year project STES for the Kori 3,4 and Younggwang 1,2 has been developed. Since there is no CARE for Wolsong(PHWR) plants yet, CARE for Wolsong is under construction. The safety parameters are selected and the safety information display screens and the alarm logic for plant status change are developed for Wolsong Unit 2 based on the design documents for CANDU plants

  10. Regulatory Technology Development Plan - Sodium Fast Reactor: Mechanistic Source Term - Trial Calculation

    International Nuclear Information System (INIS)

    Grabaskas, David

    2016-01-01

    The potential release of radioactive material during a plant incident, referred to as the source term, is a vital design metric and will be a major focus of advanced reactor licensing. The U.S. Nuclear Regulatory Commission has stated an expectation for advanced reactor vendors to present a mechanistic assessment of the potential source term in their license applications. The mechanistic source term presents an opportunity for vendors to realistically assess the radiological consequences of an incident, and may allow reduced emergency planning zones and smaller plant sites. However, the development of a mechanistic source term for advanced reactors is not without challenges, as there are often numerous phenomena impacting the transportation and retention of radionuclides. This project sought to evaluate U.S. capabilities regarding the mechanistic assessment of radionuclide release from core damage incidents at metal fueled, pool-type sodium fast reactors (SFRs). The purpose of the analysis was to identify, and prioritize, any gaps regarding computational tools or data necessary for the modeling of radionuclide transport and retention phenomena. To accomplish this task, a parallel-path analysis approach was utilized. One path, led by Argonne and Sandia National Laboratories, sought to perform a mechanistic source term assessment using available codes, data, and models, with the goal to identify gaps in the current knowledge base. The second path, performed by an independent contractor, performed sensitivity analyses to determine the importance of particular radionuclides and transport phenomena in regards to offsite consequences. The results of the two pathways were combined to prioritize gaps in current capabilities.

  11. Regulatory Technology Development Plan - Sodium Fast Reactor: Mechanistic Source Term – Trial Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Brunett, Acacia J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Denman, Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Engineering Division; Clark, Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nuclear Engineering Division; Denning, Richard S. [Consultant, Columbus, OH (United States)

    2016-10-01

    The potential release of radioactive material during a plant incident, referred to as the source term, is a vital design metric and will be a major focus of advanced reactor licensing. The U.S. Nuclear Regulatory Commission has stated an expectation for advanced reactor vendors to present a mechanistic assessment of the potential source term in their license applications. The mechanistic source term presents an opportunity for vendors to realistically assess the radiological consequences of an incident, and may allow reduced emergency planning zones and smaller plant sites. However, the development of a mechanistic source term for advanced reactors is not without challenges, as there are often numerous phenomena impacting the transportation and retention of radionuclides. This project sought to evaluate U.S. capabilities regarding the mechanistic assessment of radionuclide release from core damage incidents at metal fueled, pool-type sodium fast reactors (SFRs). The purpose of the analysis was to identify, and prioritize, any gaps regarding computational tools or data necessary for the modeling of radionuclide transport and retention phenomena. To accomplish this task, a parallel-path analysis approach was utilized. One path, led by Argonne and Sandia National Laboratories, sought to perform a mechanistic source term assessment using available codes, data, and models, with the goal to identify gaps in the current knowledge base. The second path, performed by an independent contractor, performed sensitivity analyses to determine the importance of particular radionuclides and transport phenomena in regards to offsite consequences. The results of the two pathways were combined to prioritize gaps in current capabilities.

  12. Long-term program up to fiscal 1993 of electric power source development

    International Nuclear Information System (INIS)

    Kawakami, Shin-ichi

    1984-01-01

    The long-term, ten years, program up to fiscal 1993 of electric power source development, determined by the Government aims at stable power supply and the expansion of utilization of petroleum-substitute energy. The annual growth in the gross national product (GNP) during the ten years was taken as about 4 %. So, the total electric power demand in fiscal 1993 is scheduled to be 731,000 million kwh, about 34 % up from 547,000 million kwh in fiscal 1983. The structure of electric power sources at the end of fiscal 1993 will be hydraulic 19.7 %, thermal 58.3 %, and nuclear 21.9 %. The development of electric power sources to be initiated in fiscal 1984 is hydraulic 500 MW, thermal 2,000 MW, and nuclear 6,000 MW. (Mori, K.)

  13. Development of dose calculation program (DBADOSE) incorporating alternative source term due to design basis accident

    International Nuclear Information System (INIS)

    Bae, Young Jig; Nam, Ki Mun; Lee, Yu Jong; Chung, Chan Young

    2003-01-01

    Source terms presented in TID-14844 and Regulatory Guide 1.4 have been used for radiological analysis of design basis accidents for licensing existing pressurized water reactor (PWR). However, more realistic and physically-based source term based on results of study and experiments for about 30 years after the publication of TID-14844 was developed and presented in NUREG-1465 published by U.S NRC in 1995. In addition, ICRP has revised dose concepts and criteria through the publication of ICRP-9, 26, 60 and recommended effective dose concepts rather than critical organ concept since the publication of ICRP-26. Accordingly, multipurpose computer program called DBADOSE incorporating alternative source terms in NUREG-1465 and effective dose concepts in ICRP-60 was developed. Comparison of results of DBADOSE with those of POSTDBA and STARDOSE was performed and verified and no significant difference and inaccuracy were found. DBADOSE will be used to evaluate accidental doses for licensing application according to the domestic laws that are expected to be revised in the near future

  14. Source-term development for a contaminant plume for use by multimedia risk assessment models

    International Nuclear Information System (INIS)

    Whelan, Gene; McDonald, John P.; Taira, Randal Y.; Gnanapragasam, Emmanuel K.; Yu, Charley; Lew, Christine S.; Mills, William B.

    1999-01-01

    Multimedia modelers from the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE) are collaborating to conduct a comprehensive and quantitative benchmarking analysis of four intermedia models: DOE's Multimedia Environmental Pollutant Assessment System (MEPAS), EPA's MMSOILS, EPA's PRESTO, and DOE's RESidual RADioactivity (RESRAD). These models represent typical analytically, semi-analytically, and empirically based tools that are utilized in human risk and endangerment assessments for use at installations containing radioactive and/or hazardous contaminants. Although the benchmarking exercise traditionally emphasizes the application and comparison of these models, the establishment of a Conceptual Site Model (CSM) should be viewed with equal importance. This paper reviews an approach for developing a CSM of an existing, real-world, Sr-90 plume at DOE's Hanford installation in Richland, Washington, for use in a multimedia-based benchmarking exercise bet ween MEPAS, MMSOILS, PRESTO, and RESRAD. In an unconventional move for analytically based modeling, the benchmarking exercise will begin with the plume as the source of contamination. The source and release mechanism are developed and described within the context of performing a preliminary risk assessment utilizing these analytical models. By beginning with the plume as the source term, this paper reviews a typical process and procedure an analyst would follow in developing a CSM for use in a preliminary assessment using this class of analytical tool

  15. Low-level radioactive waste source term model development and testing: Topical report

    International Nuclear Information System (INIS)

    Sullivan, T.M.; Kempf, C.R.; Suen, C.J.; Mughabghab, S.M.

    1988-08-01

    The Low-Level Waste Source Term Evaluation Project has the objective to develop a system model capable of predicting radionuclide release rates from a shallow land burial facility. The previous topical report for this project discussed the framework and methodology for developing a system model and divided the problem into four compartments: water flow, container degradation, waste form leaching, and radionuclide transport. Each of these compartments is described by submodels which will be coupled into the system model. From February 1987 to March 1988, computer models have been selected to predict water flow (FEMWATER) and radionuclide transport (FEMWASTE) and separate models have been developed to predict pitting corrosion of steel containers and leaching from porous waste forms contained in corrodible containers. This report discusses each of the models in detail and presents results obtained from applying the models to shallow land burial trenches over a range of expected conditions. 68 refs., 34 figs., 14 tabs

  16. Development of source term evaluation method for Korean Next Generation Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Keon Jae; Cheong, Jae Hak; Park, Jin Baek; Kim, Guk Gee [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-10-15

    This project had investigate several design features of radioactive waste processing system and method to predict nuclide concentration at primary coolant basic concept of next generation reactor and safety goals at the former phase. In this project several prediction methods of source term are evaluated conglomerately and detailed contents of this project are : model evaluation of nuclide concentration at Reactor Coolant System, evaluation of primary and secondary coolant concentration of reference Nuclear Power Plant(NPP), investigation of prediction parameter of source term evaluation, basic parameter of PWR, operational parameter, respectively, radionuclide removal system and adjustment values of reference NPP, suggestion of source term prediction method of next generation NPP.

  17. Development of the methodology for application of revised source term to operating nuclear power plants in Korea

    International Nuclear Information System (INIS)

    Kang, M.S.; Kang, P.; Kang, C.S.; Moon, J.H.

    2004-01-01

    Considering the current trend in applying the revised source term proposed by NUREG-1465 to the nuclear power plants in the U.S., it is expected that the revised source term will be applied to the Korean operating nuclear power plants in the near future, even though the exact time can not be estimated. To meet the future technical demands, it is necessary to prepare the technical system including the related regulatory requirements in advance. In this research, therefore, it is intended to develop the methodology to apply the revised source term to operating nuclear power plants in Korea. Several principles were established to develop the application methodologies. First, it is not necessary to modify the existing regulations about source term (i.e., any back-fitting to operating nuclear plants is not necessary). Second, if the pertinent margin of safety is guaranteed, the revised source term suggested by NUREG-1465 may be useful to full application. Finally, a part of revised source term could be selected to application based on the technical feasibility. As the results of this research, several methodologies to apply the revised source term to the Korean operating nuclear power plants have been developed, which include: 1) the selective (or limited) application to use only some of all the characteristics of the revised source term, such as release timing of fission products and chemical form of radio-iodine and 2) the full application to use all the characteristics of the revised source term. The developed methodologies are actually applied to Ulchin 9 and 4 units and their application feasibilities are reviewed. The results of this research are used as either a manual in establishing the plan and the procedure for applying the revised source term to the domestic nuclear plant from the utility's viewpoint; or a technical basis of revising the related regulations from the regulatory body's viewpoint. The application of revised source term to operating nuclear

  18. Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

    International Nuclear Information System (INIS)

    Grabaskas, David; Bucknor, Matthew; Jerden, James

    2016-01-01

    The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish release fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.

  19. Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Metal Fuel Radionuclide Release

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David [Argonne National Lab. (ANL), Argonne, IL (United States); Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States); Jerden, James [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-01

    The development of an accurate and defensible mechanistic source term will be vital for the future licensing efforts of metal fuel, pool-type sodium fast reactors. To assist in the creation of a comprehensive mechanistic source term, the current effort sought to estimate the release fraction of radionuclides from metal fuel pins to the primary sodium coolant during fuel pin failures at a variety of temperature conditions. These release estimates were based on the findings of an extensive literature search, which reviewed past experimentation and reactor fuel damage accidents. Data sources for each radionuclide of interest were reviewed to establish release fractions, along with possible release dependencies, and the corresponding uncertainty levels. Although the current knowledge base is substantial, and radionuclide release fractions were established for the elements deemed important for the determination of offsite consequences following a reactor accident, gaps were found pertaining to several radionuclides. First, there is uncertainty regarding the transport behavior of several radionuclides (iodine, barium, strontium, tellurium, and europium) during metal fuel irradiation to high burnup levels. The migration of these radionuclides within the fuel matrix and bond sodium region can greatly affect their release during pin failure incidents. Post-irradiation examination of existing high burnup metal fuel can likely resolve this knowledge gap. Second, data regarding the radionuclide release from molten high burnup metal fuel in sodium is sparse, which makes the assessment of radionuclide release from fuel melting accidents at high fuel burnup levels difficult. This gap could be addressed through fuel melting experimentation with samples from the existing high burnup metal fuel inventory.

  20. Regulatory Technology Development Plan - Sodium Fast Reactor. Mechanistic Source Term - Trial Calculation. Work Plan

    International Nuclear Information System (INIS)

    Grabaskas, David; Bucknor, Matthew; Jerden, James; Brunett, Acacia J.

    2016-01-01

    The overall objective of the SFR Regulatory Technology Development Plan (RTDP) effort is to identify and address potential impediments to the SFR regulatory licensing process. In FY14, an analysis by Argonne identified the development of an SFR-specific MST methodology as an existing licensing gap with high regulatory importance and a potentially long lead-time to closure. This work was followed by an initial examination of the current state-of-knowledge regarding SFR source term development (ANLART-3), which reported several potential gaps. Among these were the potential inadequacies of current computational tools to properly model and assess the transport and retention of radionuclides during a metal fuel pool-type SFR core damage incident. The objective of the current work is to determine the adequacy of existing computational tools, and the associated knowledge database, for the calculation of an SFR MST. To accomplish this task, a trial MST calculation will be performed using available computational tools to establish their limitations with regard to relevant radionuclide release/retention/transport phenomena. The application of existing modeling tools will provide a definitive test to assess their suitability for an SFR MST calculation, while also identifying potential gaps in the current knowledge base and providing insight into open issues regarding regulatory criteria/requirements. The findings of this analysis will assist in determining future research and development needs.

  1. Source term development for the 300 Area Treated Effluent Disposal Facility

    International Nuclear Information System (INIS)

    Bendixsen, R.B.

    1994-04-01

    A novel method for developing a source term for radiation and hazardous material content of sludge processing equipment and barrels in a new waste water treatment facility is presented in this paper. The 300 Area Treated Effluent Disposal Facility (TEDF), located at the Hanford Site near Richland, Washington, will treat process sewer waste water from the 300 Area and discharge a permittable effluent flow into the Columbia River. A process information and hazards analysis document needed a process flowsheet detailing the concentrations of radionuclides, inorganics, and organics throughout the process, including the sludge effluent flow. A hazards analysis for a processing facility usually includes a flowsheet showing the process, materials, heat balances, and instrumentation for that facility. The flow sheet estimates stream flow quantities, activities, compositions, and properties. For the 300 Area TEDF, it was necessary to prepare the flow sheet with all of the information so that radiation doses to workers could be estimated. The noble method used to develop the 300 Area TEDF flowsheet included generating recycle factors. To prepare each component in the flowsheet, precipitation, destruction, and two recycle factors were developed. The factors were entered into a spreadsheet and provided a method of estimating the steady-state concentrations of all of the components in the facility. This report describes how the factors were developed, explains how they were used in developing the flowsheet, and presents the results of using these values to estimate radiation doses for personnel working in the facility. The report concludes with a discussion of the effect of estimates of radioactive and hazardous material concentrations on shielding design and the need for containment features for equipment in the facility

  2. Chernobyl source term estimation

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Harvey, T.F.; Lange, R.

    1990-09-01

    The Chernobyl source term available for long-range transport was estimated by integration of radiological measurements with atmospheric dispersion modeling and by reactor core radionuclide inventory estimation in conjunction with WASH-1400 release fractions associated with specific chemical groups. The model simulations revealed that the radioactive cloud became segmented during the first day, with the lower section heading toward Scandinavia and the upper part heading in a southeasterly direction with subsequent transport across Asia to Japan, the North Pacific, and the west coast of North America. By optimizing the agreement between the observed cloud arrival times and duration of peak concentrations measured over Europe, Japan, Kuwait, and the US with the model predicted concentrations, it was possible to derive source term estimates for those radionuclides measured in airborne radioactivity. This was extended to radionuclides that were largely unmeasured in the environment by performing a reactor core radionuclide inventory analysis to obtain release fractions for the various chemical transport groups. These analyses indicated that essentially all of the noble gases, 60% of the radioiodines, 40% of the radiocesium, 10% of the tellurium and about 1% or less of the more refractory elements were released. These estimates are in excellent agreement with those obtained on the basis of worldwide deposition measurements. The Chernobyl source term was several orders of magnitude greater than those associated with the Windscale and TMI reactor accidents. However, the 137 Cs from the Chernobyl event is about 6% of that released by the US and USSR atmospheric nuclear weapon tests, while the 131 I and 90 Sr released by the Chernobyl accident was only about 0.1% of that released by the weapon tests. 13 refs., 2 figs., 7 tabs

  3. The Chernobyl reactor accident source term: development of a consensus view

    International Nuclear Information System (INIS)

    Devell, L.; Guntay, S.; Powers, D.A.

    1995-11-01

    Ten years after the reactor accident at Chernobyl, a great deal more data is available concerning the events, phenomena, and processes that took place. The purpose of this document is to examine what is known about the radioactive materials released during the accident, a task that is substantially more difficult than it might first appear to be. The Chernobyl station, like other nuclear power plants, was not instrumented to characterize a disastrous accident. The accident was peculiar in the sense that radioactive materials were released, at least initially, in an exceptionally energetic plume and were transported far from the reactor site. Release of radioactivity from the plant continued for several days. Characterization of the contamination caused by the releases of radioactivity has had a much lower priority than remediation of the contamination. Consequently, an assessment of the Chernobyl accident source term must rely to a significant extent on inferential evidence. The assessment presented here begins with an examination of the core inventories of radioactive materials. In subsequent sections of the report, the magnitude and timing of the releases of radioactivity are described. Then, the composition, chemical forms, and physical forms of the releases are discussed. A number of more recent publications and results from scientists in Russia and elsewhere have significantly improved the understanding of the Chernobyl source term. Because of the special features of the reactor design and the peculiarities of the Chernobyl accident, the source term for the Chernobyl accident is of limited applicability to the safety analysis of other types of reactors

  4. The development of a realistic source term for sodium-cooled fast reactors : assessment of current status and future needs.

    Energy Technology Data Exchange (ETDEWEB)

    LaChance, Jeffrey L.; Phillips, Jesse; Parma, Edward J., Jr.; Olivier, Tara Jean; Middleton, Bobby D.

    2011-06-01

    Sodium-cooled fast reactors (SFRs) continue to be proposed and designed throughout the United States and the world. Although the number of SFRs actually operating has declined substantially since the 1980s, a significant interest in advancing these types of reactor systems remains. Of the many issues associated with the development and deployment of SFRs, one of high regulatory importance is the source term to be used in the siting of the reactor. A substantial amount of modeling and experimental work has been performed over the past four decades on accident analysis, sodium coolant behavior, and radionuclide release for SFRs. The objective of this report is to aid in determining the gaps and issues related to the development of a realistic, mechanistically derived source term for SFRs. This report will allow the reader to become familiar with the severe accident source term concept and gain a broad understanding of the current status of the models and experimental work. Further, this report will allow insight into future work, in terms of both model development and experimental validation, which is necessary in order to develop a realistic source term for SFRs.

  5. The Chernobyl reactor accident source term: Development of a consensus view

    International Nuclear Information System (INIS)

    Guntay, S.; Powers, D.A.; Devell, L.

    1997-01-01

    In August 1986, scientists from the former Soviet Union provided the nuclear safety community with an impressively detailed account of what was then known about the Chernobyl accident. This included assessments of the magnitudes, rates, and compositions of radionuclide releases during the ten days following initiation of the accident. A summary report based on the Soviet report, the oral presentations, and the discussions with scientists from various countries was issued by the International Atomic Energy Agency shortly thereafter. Ten years have elapsed since the reactor accident at Chernobyl. A great deal more data is now available concerning the events, phenomena, and processes that took place. The purpose of this document is to examine what is known about the radioactive materials released during the accident. The accident was peculiar in the sense that radioactive materials were released, at least initially, in an exceptionally energetic plume and were transported far from the reactor site. Release of radioactivity from the plant continued for about ten days. A number of more recent publications and results from scientists in Russia and elsewhere have significantly improved our understanding of the Chernobyl source term. Because of the special features of the reactor design and the pecularities of the Chernobyl accident, the source term for the Chernobyl accident is of limited applicability of the safety analysis of other types of reactors

  6. Emergency preparedness source term development for the Office of Nuclear Material Safety and Safeguards-Licensed Facilities

    International Nuclear Information System (INIS)

    Sutter, S.L.; Mishima, J.; Ballinger, M.Y.; Lindsey, C.G.

    1984-08-01

    In order to establish requirements for emergency preparedness plans at facilities licensed by the Office of Nuclear Materials Safety and Safeguards, the Nuclear Regulatory Commission (NRC) needs to develop source terms (the amount of material made airborne) in accidents. These source terms are used to estimate the potential public doses from the events, which, in turn, will be used to judge whether emergency preparedness plans are needed for a particular type of facility. Pacific Northwest Laboratory is providing the NRC with source terms by developing several accident scenarios for eleven types of fuel cycle and by-product operations. Several scenarios are developed for each operation, leading to the identification of the maximum release considered for emergency preparedness planning (MREPP) scenario. The MREPP scenarios postulated were of three types: fire, tornado, and criticality. Fire was significant at oxide fuel fabrication, UF 6 production, radiopharmaceutical manufacturing, radiopharmacy, sealed source manufacturing, waste warehousing, and university research and development facilities. Tornadoes were MREPP events for uranium mills and plutonium contaminated facilities, and criticalities were significant at nonoxide fuel fabrication and nuclear research and development facilities. Techniques for adjusting the MREPP release to different facilities are also described

  7. Fission-product source terms

    International Nuclear Information System (INIS)

    Lorenz, R.A.

    1981-01-01

    This presentation consists of a review of fission-product source terms for light water reactor (LWR) fuel. A source term is the quantity of fission products released under specified conditions that can be used to calculate the consequences of the release. The source term usually defines release from breached fuel-rod cladding but could also describe release from the primary coolant system, the reactor containment shell, or the site boundary. The source term would be different for each locality, and the chemical and physical forms of the fission products could also differ

  8. Development of Coupled Interface System between the FADAS Code and a Source-term Evaluation Code XSOR for CANDU Reactors

    International Nuclear Information System (INIS)

    Son, Han Seong; Song, Deok Yong; Kim, Ma Woong; Shin, Hyeong Ki; Lee, Sang Kyu; Kim, Hyun Koon

    2006-01-01

    An accident prevention system is essential to the industrial security of nuclear industry. Thus, the more effective accident prevention system will be helpful to promote safety culture as well as to acquire public acceptance for nuclear power industry. The FADAS(Following Accident Dose Assessment System) which is a part of the Computerized Advisory System for a Radiological Emergency (CARE) system in KINS is used for the prevention against nuclear accident. In order to enhance the FADAS system more effective for CANDU reactors, it is necessary to develop the various accident scenarios and reliable database of source terms. This study introduces the construction of the coupled interface system between the FADAS and the source-term evaluation code aimed to improve the applicability of the CANDU Integrated Safety Analysis System (CISAS) for CANDU reactors

  9. Design parameters and source terms: Volume 3, Source terms

    International Nuclear Information System (INIS)

    1987-10-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report by Stearns Catalytic Corporation (SCC), entitled ''Design Parameters and Source Terms for a Two-Phase Repository in Salt,'' 1985, to the level of the Site Characterization Plan - Conceptual Design Report. The previous unpublished SCC Study identifies the data needs for the Environmental Assessment effort for seven possible Salt Repository sites. 11 refs., 9 tabs

  10. Accident-generated radioactive particle source term development for consequence assessment of nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Sutter, S.L.; Ballinger, M.Y.; Halverson, M.A.; Mishima, J.

    1983-04-01

    Consequences of nuclear fuel cycle facility accidents can be evaluated using aerosol release factors developed at Pacific Northwest Laboratory. These experimentally determined factors are compiled and consequence assessment methods are discussed. Release factors can be used to estimate the fraction of material initially made airborne by postulated accident scenarios. These release fractions in turn can be used in models to estimate downwind contamination levels as required for safety assessments of nuclear fuel cycle facilities. 20 references, 4 tables

  11. Progress in development of a source term for sphene glass-ceramic dissolution under vault conditions

    International Nuclear Information System (INIS)

    Hayward, P.J.; Tait, J.C.; George, I.M.; Carmichael, A.A.; Ross, J.M.P.

    1986-01-01

    This report describes the results of ongoing leaching experiments, involving aluminosilicate glass and sphene (CaTiSiO/sub 5/) ceramics, doped with /sup 22/Na or /sup 45/Ca, and leached in a simulated Ca-NA-Cl brine at 25 0 or 100 0 C. The experiments are designed to aid development of separate models for the dissolution of the glass and the ceramic phase in a sphene glass-ceramic, and to help evaluate a composite model for the dissolution of the glass-ceramic

  12. Development of computer-based function to estimate radioactive source term by coupling atmospheric model with monitoring data

    International Nuclear Information System (INIS)

    Akiko, Furuno; Hideyuki, Kitabata

    2003-01-01

    Full text: The importance of computer-based decision support systems for local and regional scale accidents has been recognized by many countries with the experiences of accidental atmospheric releases of radionuclides at Chernobyl in 1986 in the former Soviet Union. The recent increase of nuclear power plants in the Asian region also necessitates an emergency response system for Japan to predict the long-range atmospheric dispersion of radionuclides due to overseas accident. On the basis of these backgrounds, WSPEEDI (Worldwide version of System for Prediction of Environmental Emergency Dose Information) at Japan Atomic Energy Research Institute is developed to forecast long-range atmospheric dispersions of radionuclides during nuclear emergency. Although the source condition is critical parameter for accurate prediction, it is rarely that the condition can be acquired in the early stage of overseas accident. Thus, we have been developing a computer-based function to estimate radioactive source term, e.g. the release point, time and amount, as a part of WSPEEDI. This function consists of atmospheric transport simulations and statistical analysis for the prediction and monitoring of air dose rates. Atmospheric transport simulations are carried out for the matrix of possible release points in Eastern Asia and possible release times. The simulation results of air dose rates are compared with monitoring data and the best fitted release condition is defined as source term. This paper describes the source term estimation method and the application to Eastern Asia. The latest version of WSPEEDI accommodates following two models: an atmospheric meteorological model MM5 and a particle random walk model GEARN. MM5 is a non-hydrostatic meteorological model developed by the Pennsylvania State University and the National Center for Atmospheric Research (NCAR). MM5 physically calculates more than 40 meteorological parameters with high resolution in time and space based an

  13. Development of a tool dedicated to the evaluation of hydrogen term source for technological Wastes: assumptions, physical models, and validation

    Energy Technology Data Exchange (ETDEWEB)

    Lamouroux, C. [CEA Saclay, Nuclear Energy Division /DANS, Department of physico-chemistry, 91191 Gif sur yvette (France); Esnouf, S. [CEA Saclay, DSM/IRAMIS/SIS2M/Radiolysis Laboratory , 91191 Gif sur yvette (France); Cochin, F. [Areva NC,recycling BU, DIRP/RDP tour Areva, 92084 Paris La Defense (France)

    2013-07-01

    In radioactive waste packages hydrogen is generated, in one hand, from the radiolysis of wastes (mainly organic materials) and, in the other hand, from the radiolysis of water content in the cement matrix. In order to assess hydrogen generation 2 tools based on operational models have been developed. One is dedicated to the determination of the hydrogen source term issues from the radiolysis of the wastes: the STORAGE tool (Simulation Tool Of Emission Radiolysis Gas), the other deals with the hydrogen source term gas, produced by radiolysis of the cement matrices (the Damar tool). The approach used by the STORAGE tool for assessing the production rate of radiolysis gases is divided into five steps: 1) Specification of the data packages, in particular, inventories and radiological materials defined for a package medium; 2) Determination of radiochemical yields for the different constituents and the laws of behavior associated, this determination of radiochemical yields is made from the PRELOG database in which radiochemical yields in different irradiation conditions have been compiled; 3) Definition of hypothesis concerning the composition and the distribution of contamination inside the package to allow assessment of the power absorbed by the constituents; 4) Sum-up of all the contributions; And finally, 5) validation calculations by comparison with a reduced sampling of packages. Comparisons with measured values confirm the conservative character of the methodology and give confidence in the safety margins for safety analysis report.

  14. SOURCE TERMS FOR HLW GLASS CANISTERS

    International Nuclear Information System (INIS)

    J.S. Tang

    2000-01-01

    This calculation is prepared by the Monitored Geologic Repository (MGR) Waste Package Design Section. The objective of this calculation is to determine the source terms that include radionuclide inventory, decay heat, and radiation sources due to gamma rays and neutrons for the high-level radioactive waste (HLW) from the, West Valley Demonstration Project (WVDP), Savannah River Site (SRS), Hanford Site (HS), and Idaho National Engineering and Environmental Laboratory (INEEL). This calculation also determines the source terms of the canister containing the SRS HLW glass and immobilized plutonium. The scope of this calculation is limited to source terms for a time period out to one million years. The results of this calculation may be used to carry out performance assessment of the potential repository and to evaluate radiation environments surrounding the waste packages (WPs). This calculation was performed in accordance with the Development Plan ''Source Terms for HLW Glass Canisters'' (Ref. 7.24)

  15. Open Source Software Development

    Science.gov (United States)

    2011-01-01

    appropriate to refer to FOSS or FLOSS (L for Libre , where the alternative term “ libre software ” has popularity in some parts of the world) in order...Applying Social Network Analysis to Community-Drive Libre Software Projects, Intern. J. Info. Tech. and Web Engineering, 2006, 1(3), 27-28. 17...Open Source Software Development* Walt Scacchi Institute for Software Researcher University of California, Irvine Irvine, CA 92697-3455 USA Abstract

  16. Pennsylvania Source Term Tracking System

    International Nuclear Information System (INIS)

    1992-08-01

    The Pennsylvania Source Term Tracking System tabulates surveys received from radioactive waste generators in the Commonwealth of radioactive waste is collected each quarter from generators using the Low-Level Radioactive Waste Management Quarterly Report Form (hereafter called the survey) and then entered into the tracking system data base. This personal computer-based tracking system can generate 12 types of tracking reports. The first four sections of this reference manual supply complete instructions for installing and setting up the tracking system on a PC. Section 5 presents instructions for entering quarterly survey data, and Section 6 discusses generating reports. The appendix includes samples of each report

  17. Severe accident source term reassessment

    International Nuclear Information System (INIS)

    Hazzan, M.J.; Gardner, R.; Warman, E.A.; Jacobs, S.B.

    1987-01-01

    This paper summarizes the status of the reassessment of severe reactor accident source terms, which are defined as the quantity, type, and timing of fission product releases from such accidents. Concentration is on the major results and conclusions of analyses with modern methods for both pressurized water reactors (PWRs) and boiling water reactors (BWRs), and the special case of containment bypass. Some distinctions are drawn between analyses for PWRs and BWRs. In general, the more the matter is examined, the consequences, or probability of serious consequences, seem to be less. (author)

  18. Source Term Model for Fine Particle Resuspension from Indoor Surfaces

    National Research Council Canada - National Science Library

    Kim, Yoojeong; Gidwani, Ashok; Sippola, Mark; Sohn, Chang W

    2008-01-01

    This Phase I effort developed a source term model for particle resuspension from indoor surfaces to be used as a source term boundary condition for CFD simulation of particle transport and dispersion in a building...

  19. Subsurface Shielding Source Term Specification Calculation

    International Nuclear Information System (INIS)

    S.Su

    2001-01-01

    The purpose of this calculation is to establish appropriate and defensible waste-package radiation source terms for use in repository subsurface shielding design. This calculation supports the shielding design for the waste emplacement and retrieval system, and subsurface facility system. The objective is to identify the limiting waste package and specify its associated source terms including source strengths and energy spectra. Consistent with the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M and O 2001, p. 15), the scope of work includes the following: (1) Review source terms generated by the Waste Package Department (WPD) for various waste forms and waste package types, and compile them for shielding-specific applications. (2) Determine acceptable waste package specific source terms for use in subsurface shielding design, using a reasonable and defensible methodology that is not unduly conservative. This calculation is associated with the engineering and design activity for the waste emplacement and retrieval system, and subsurface facility system. The technical work plan for this calculation is provided in CRWMS M and O 2001. Development and performance of this calculation conforms to the procedure, AP-3.12Q, Calculations

  20. Hazardous constituent source term. Revision 2

    International Nuclear Information System (INIS)

    1994-01-01

    The Department of Energy (DOE) has several facilities that either generate and/or store transuranic (TRU)-waste from weapons program research and production. Much of this waste also contains hazardous waste constituents as regulated under Subtitle C of the Resource Conservation and Recovery Act (RCRA). Toxicity characteristic metals in the waste principally include lead, occurring in leaded rubber gloves and shielding. Other RCRA metals may occur as contaminants in pyrochemical salt, soil, debris, and sludge and solidified liquids, as well as in equipment resulting from decontamination and decommissioning activities. Volatile organic compounds (VOCS) contaminate many waste forms as a residue adsorbed on surfaces or occur in sludge and solidified liquids. Due to the presence of these hazardous constituents, applicable disposal regulations include land disposal restrictions established by Hazardous and Solid Waste Amendments (HSWA). The DOE plans to dispose of TRU-mixed waste from the weapons program in the Waste Isolation Pilot Plant (WIPP) by demonstrating no-migration of hazardous constituents. This paper documents the current technical basis for methodologies proposed to develop a post-closure RCRA hazardous constituent source term. For the purposes of demonstrating no-migration, the hazardous constituent source term is defined as the quantities of hazardous constituents that are available for transport after repository closure. Development of the source term is only one of several activities that will be involved in the no-migration demonstration. The demonstration will also include uncertainty and sensitivity analyses of contaminant transport

  1. Spent fuel assembly source term parameters

    International Nuclear Information System (INIS)

    Barrett, P.R.; Foadian, H.; Rashid, Y.R.; Seager, K.D.; Gianoulakis, S.E.

    1993-01-01

    Containment of cask contents by a transport cask is a function of the cask body, one or more closure lids, and various bolting hardware, and seals associated with the cavity closure and other containment penetrations. In addition, characteristics of cask contents that impede the ability of radionuclides to move from an origin to the external environment also provide containment. In essence, multiple release barriers exist in series in transport casks, and the magnitude of the releasable activity in the cask is considerably lower than the total activity of its contents. A source term approach accounts for the magnitude of the releasable activity available in the cask by assessing the degree of barrier resistance to release provided by material characteristics and inherent barriers that impede the release of radioactive contents. Standardized methodologies for defining the spent-fuel transport packages with specified regulations have recently been developed. An essential part of applying the source term methodology involves characterizing the response of the spent fuel under regulatory conditions of transport. Thermal and structural models of the cask and fuel are analyzed and used to predict fuel rod failure probabilities. Input to these analyses and failure evaluations cover a wide range of geometrical and material properties. An important issue in the development of these models is the sensitivity of the radioactive source term generated during transport to individual parameters such as temperature and fluence level. This paper provides a summary of sensitivity analyses concentrating on the structural response and failure predictions of the spent fuel assemblies

  2. Development of a comprehensive source term model for the Subsurface Disposal Area at the Idaho National Engineering and Environmental Laboratory

    International Nuclear Information System (INIS)

    1997-01-01

    The first detailed comprehensive simulation study to evaluate fate and transport of wastes disposed in the Subsurface Disposal Area (SDA), at the Radioactive Waste Management Complex (RWMC), Idaho National Engineering and Environmental Laboratory (INEEL) has recently been conducted. One of the most crucial parts of this modeling was the source term or release model. The current study used information collected over the last five years defining contaminant specific information including: the amount disposed, the waste form (physical and chemical properties) and the type of container used for each contaminant disposed. This information was used to simulate the release of contaminants disposed in the shallow subsurface at the SDA. The DUST-MS model was used to simulate the release. Modifications were made to allow the yearly disposal information to be incorporated. The modeling includes unique container and release rate information for each of the 42 years of disposal. The results from this simulation effort are used for both a groundwater and a biotic uptake evaluation. As part of this modeling exercise, inadequacies in the available data relating to the release of contaminants have been identified. The results from this modeling study have been used to guide additional data collection activities at the SDA for purposes of increasing confidence in the appropriateness of model predictions

  3. Real time source term and dose assessment

    International Nuclear Information System (INIS)

    Breznik, B.; Kovac, A.; Mlakar, P.

    2001-01-01

    The Dose Projection Programme is a tool for decision making in case of nuclear emergency. The essential input data for quick emergency evaluation in the case of hypothetical pressurised water reactor accident are following: source term, core damage assessment, fission product radioactivity, release source term and critical exposure pathways for an early phase of the release. A reduced number of radio-nuclides and simplified calculations can be used in dose calculation algorithm. Simple expert system personal computer programme has been developed for the Krsko Nuclear Power Plant for dose projection within the radius of few kilometers from the pressurised water reactor in early phase of an accident. The input data are instantaneous data of core activity, core damage indicators, release fractions, reduction factor of the release pathways, spray operation, release timing, and dispersion coefficient. Main dose projection steps are: accurate in-core radioactivity determination using reactor power input; core damage and in-containment source term assessment based on quick indications of instrumentation or on activity analysis data; user defines release pathway for typical PWR accident scenarius; dose calculation is performed only for exposure pathway critical for decision about evacuation or sheltering in early phase of an accident.(author)

  4. Calculation of source terms for NUREG-1150

    International Nuclear Information System (INIS)

    Breeding, R.J.; Williams, D.C.; Murfin, W.B.; Amos, C.N.; Helton, J.C.

    1987-10-01

    The source terms estimated for NUREG-1150 are generally based on the Source Term Code Package (STCP), but the actual source term calculations used in computing risk are performed by much smaller codes which are specific to each plant. This was done because the method of estimating the uncertainty in risk for NUREG-1150 requires hundreds of source term calculations for each accident sequence. This is clearly impossible with a large, detailed code like the STCP. The small plant-specific codes are based on simple algorithms and utilize adjustable parameters. The values of the parameters appearing in these codes are derived from the available STCP results. To determine the uncertainty in the estimation of the source terms, these parameters were varied as specified by an expert review group. This method was used to account for the uncertainties in the STCP results and the uncertainties in phenomena not considered by the STCP

  5. Development of Level-2 PSA Technology: A Development of the Database of the Parametric Source Term for Kori Unit 1 Using the MAAP4 Code

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chang Soon; Mun, Ju Hyun; Yun, Jeong Ick; Cho, Young Hoo; Kim, Chong Uk [Seoul National University, Seoul (Korea, Republic of)

    1997-07-15

    To quantify the severe accident source term of the parametric model method, the uncertainty of the parameters should be analyzed. Generally, to analyze the uncertainties, the cumulative distribution functions(CDF`S) of the parameters are derived. This report introduces a method of derivation of the CDF`s of the basic parameters, FCOR, FVES and FDCH. The calculation tool of the source term is the MAAP version 4.0. In the MAAP code, there are model parameters to consider an uncertain physical and/or chemical phenomenon. In general, the parameters have not a point value but a range. In this paper, considering this point, the input values of model parameters influencing each parameter are sampled using LHS. Then, the calculation results are shown in the cumulative distribution form. For a case study, the CDF`s of FCOR, FVES and FDCH of KORI unit 1 are derived. The target scenarios for the calculation are the ones whose initial events are large LOCA, small LOCA and transient, respectively. It is found that the distributions of this study are consistent to those of NUREG-1150 and are proven to be adequate in assessing the uncertainties in the severe accident source term of KORI Unit 1. 15 refs., 27 tabs., 4 figs. (author)

  6. Mechanistic facility safety and source term analysis

    International Nuclear Information System (INIS)

    PLYS, M.G.

    1999-01-01

    A PC-based computer program was created for facility safety and source term analysis at Hanford The program has been successfully applied to mechanistic prediction of source terms from chemical reactions in underground storage tanks, hydrogen combustion in double contained receiver tanks, and proccss evaluation including the potential for runaway reactions in spent nuclear fuel processing. Model features include user-defined facility room, flow path geometry, and heat conductors, user-defined non-ideal vapor and aerosol species, pressure- and density-driven gas flows, aerosol transport and deposition, and structure to accommodate facility-specific source terms. Example applications are presented here

  7. Evolution of source term definition and analysis

    International Nuclear Information System (INIS)

    Lutz, R.J. Jr.

    2004-01-01

    The objective of this presentation was to provide an overview of the evolution of accident fission product release analysis methodology and the obtained results; and to provide an overview of the source term implementation analysis in regulatory decisions

  8. Development of a general model to predict the rate of radionuclide release (source term) from a low-level waste shallow land burial facility

    International Nuclear Information System (INIS)

    Sullivan, T.M.; Kempf, C.R.; Suen, C.J.; Mughabghab, S.M.

    1988-01-01

    Federal Code of Regulations 10 CFR 61 requires that any near surface disposal site be capable of being characterized, analyzed, and modeled. The objective of this program is to assist NRC in developing the ability to model a disposal site that conforms to these regulations. In particular, a general computer model capable of predicting the quantity and rate of radionuclide release from a shallow land burial trench, i.e., the source term, is being developed. The framework for this general model has been developed and consists of four basic compartments that represent the major processes that influence release. These compartments are: water flow, container degradation, release from the waste packages, and radionuclide transport. Models for water flow and radionuclide transport rely on the use of the computer codes FEMWATER and FEMWASTE. These codes are generally regarded as being state-of-the-art and required little modification for their application to this project. Models for container degradation and release from waste packages have been specifically developed for this project. This paper provides a brief description of the models being used in the source term project and examples of their use over a range of potential conditions. 13 refs

  9. Particle beam source development

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Electron beam research directed toward providing improved in-diode pinched beam sources and establishing the efficiency and feasibility for superposition of many beams progressed in three major areas. Focusing stability has been improved from large effective aspect ratio (radius/gap of emitting surface) diodes. Substantial progress toward establishing the feasibility of combining beams guided along ionized current-carrying channels has been made. Two beams have been transported and overlayed on a target. Theoretical and experimental measurements on channel formation have resulted in specifications for the capacitor bank channel initiation system for a 12-beam combination experiment on Proto II. An additional area of beam research has been the development of a small pulsed X-ray source to yield high quality flash X-radiography of pellets. A source yielding approximately 100-μm resolution of objects has been demonstrated and work continues to improve the convenience and reliability of this source. The effort to extend the capability of higher power conventional pulse power generators to accelerate ions (rather than electrons), and assess the feasibility of this technology variation for target experiments and reactors has progressed. Progress toward development of a multistage accelerator for ions with pulse power technology centered on development of a new laboratory facility and design and procurement of hardware for a five-stage test apparatus for the Pulslac concept

  10. NSLS source development laboratory

    International Nuclear Information System (INIS)

    Ben-Zvi, I.; Blum, E.; Johnson, E.D.

    1995-01-01

    The National Synchrotron Light Source (NSLS) has initiated an ambitious project to develop fourth generation radiation sources. To achieve this goal, the Source Development Laboratory (SDL) builds on the experience gained at the NSLS, and at the highly successful BNL Accelerator Test Facility. The SDL accelerator system will consist of a high brightness short pulse linac, a station for coherent synchrotron and transition radiation experiments, a short bunch storage ring, and an ultra-violet free electron laser utilizing the NISUS wiggler. The electrons will be provided by a laser photocathode gun feeding a 210 MeV S-band electron linac, with magnetic bunch compression at 80 MeV. Electron bunches as short as 100 μm with 1 nC charge will be used for pump-probe experiments utilizing coherent transition radiation. Beam will also be injected into a compact storage ring which will be a source of millimeter wave coherent synchrotron radiation. The linac will also serve as the driver for an FEL designed to allow the study of various aspects of single pass amplifiers. The first FEL configuration will be as a self-amplified spontaneous emission (SASE) FEL at 900 nm. Seeded beam and sub-harmonic seeded beam operations will push the output wavelength below 200 nm. Chirped pulse amplification (CPA) operation will also be possible, and a planned energy upgrade (by powering a fifth linac section) to 310 MeV will extend the wavelength range of the FEL to below 100 nm

  11. Aerosol behavior and light water reactor source terms

    International Nuclear Information System (INIS)

    Abbey, F.; Schikarski, W.O.

    1988-01-01

    The major developments in nuclear aerosol modeling following the accident to pressurized water reactor Unit 2 at Three Mile Island are briefly reviewed and the state of the art summarized. The importance and implications of these developments for severe accident source terms for light water reactors are then discussed in general terms. The treatment is not aimed at identifying specific source term values but is intended rather to illustrate trends, to assess the adequacy of the understanding of major aspects of aerosol behavior for source term prediction, and demonstrate in qualitative terms the effect of various aspects of reactor design. Areas where improved understanding of aerosol behavior might lead to further reductions in current source terms predictions are also considered

  12. Radiological and chemical source terms for Solid Waste Operations Complex

    International Nuclear Information System (INIS)

    Boothe, G.F.

    1994-01-01

    The purpose of this document is to describe the radiological and chemical source terms for the major projects of the Solid Waste Operations Complex (SWOC), including Project W-112, Project W-133 and Project W-100 (WRAP 2A). For purposes of this document, the term ''source term'' means the design basis inventory. All of the SWOC source terms involve the estimation of the radiological and chemical contents of various waste packages from different waste streams, and the inventories of these packages within facilities or within a scope of operations. The composition of some of the waste is not known precisely; consequently, conservative assumptions were made to ensure that the source term represents a bounding case (i.e., it is expected that the source term would not be exceeded). As better information is obtained on the radiological and chemical contents of waste packages and more accurate facility specific models are developed, this document should be revised as appropriate. Radiological source terms are needed to perform shielding and external dose calculations, to estimate routine airborne releases, to perform release calculations and dose estimates for safety documentation, to calculate the maximum possible fire loss and specific source terms for individual fire areas, etc. Chemical source terms (i.e., inventories of combustible, flammable, explosive or hazardous chemicals) are used to determine combustible loading, fire protection requirements, personnel exposures to hazardous chemicals from routine and accident conditions, and a wide variety of other safety and environmental requirements

  13. Some practical implications of source term reassessment

    International Nuclear Information System (INIS)

    1988-03-01

    This report provides a brief summary of the current knowledge of severe accident source terms and suggests how this knowledge might be applied to a number of specific aspects of reactor safety. In preparing the report, consideration has been restricted to source term issues relating to light water reactors (LWRs). Consideration has also generally been restricted to the consequences of hypothetical severe accidents rather than their probability of occurrence, although it is recognized that, in the practical application of source term research, it is necessary to take account of probability as well as consequences. The specific areas identified were as follows: Exploration of the new insights that are available into the management of severe accidents; Investigating the impact of source term research on emergency planning and response; Assessing the possibilities which exist in present reactor designs for preventing or mitigating the consequences of severe accidents and how these might be used effectively; Exploring the need for backfitting and assessing the implications of source term research for future designs; and Improving the quantification of the radiological consequences of hypothetical severe accidents for probabilistic safety assessments (PSAs) and informing the public about the realistic risks associated with nuclear power plants. 7 refs

  14. Effect of source term composition on offsite doses

    International Nuclear Information System (INIS)

    Karahalios, P.; Gardner, R.

    1985-01-01

    The development of new realistic accident source terms has identified the need to establish a basis for comparing the impact of such source terms. This paper attempts to develop a generalized basis of comparison by investigating contributions to offsite acute whole body doses from each group of radionuclides being released to the atmosphere, using CRAC2. The paper also investigates the effect of important parameters such as regional meteorology, sheltering, and duration of release. Finally, the paper focuses on significant changes in the relative importance of individual radionuclide groups in PWR2, SST1, and a revision of the Stone and Webster proposed interim source term

  15. Scoping Analysis of Source Term and Functional Containment Attenuation Factors

    Energy Technology Data Exchange (ETDEWEB)

    Pete Lowry

    2012-10-01

    In order to meet future regulatory requirements, the Next Generation Nuclear Plant (NGNP) Project must fully establish and validate the mechanistic modular high temperature gas-cooled reactor (HTGR) source term. This is not possible at this stage in the project, as significant uncertainties in the final design remain unresolved. In the interim, however, there is a need to establish an approximate characterization of the source term. The NGNP team developed a simplified parametric model to establish mechanistic source term estimates for a set of proposed HTGR configurations.

  16. Scoping Analysis of Source Term and Functional Containment Attenuation Factors

    Energy Technology Data Exchange (ETDEWEB)

    Pete Lowry

    2012-02-01

    In order to meet future regulatory requirements, the Next Generation Nuclear Plant (NGNP) Project must fully establish and validate the mechanistic modular high temperature gas-cooled reactor (HTGR) source term. This is not possible at this stage in the project, as significant uncertainties in the final design remain unresolved. In the interim, however, there is a need to establish an approximate characterization of the source term. The NGNP team developed a simplified parametric model to establish mechanistic source term estimates for a set of proposed HTGR configurations.

  17. Scoping Analysis of Source Term and Functional Containment Attenuation Factors

    Energy Technology Data Exchange (ETDEWEB)

    Pete Lowry

    2012-01-01

    In order to meet future regulatory requirements, the Next Generation Nuclear Plant (NGNP) Project must fully establish and validate the mechanistic modular high temperature gas-cooled reactor (HTGR) source term. This is not possible at this stage in the project, as significant uncertainties in the final design remain unresolved. In the interim, however, there is a need to establish an approximate characterization of the source term. The NGNP team developed a simplified parametric model to establish mechanistic source term estimates for a set of proposed HTGR configurations.

  18. Source term modelling parameters for Project-90

    International Nuclear Information System (INIS)

    Shaw, W.; Smith, G.; Worgan, K.; Hodgkinson, D.; Andersson, K.

    1992-04-01

    This document summarises the input parameters for the source term modelling within Project-90. In the first place, the parameters relate to the CALIBRE near-field code which was developed for the Swedish Nuclear Power Inspectorate's (SKI) Project-90 reference repository safety assessment exercise. An attempt has been made to give best estimate values and, where appropriate, a range which is related to variations around base cases. It should be noted that the data sets contain amendments to those considered by KBS-3. In particular, a completely new set of inventory data has been incorporated. The information given here does not constitute a complete set of parameter values for all parts of the CALIBRE code. Rather, it gives the key parameter values which are used in the constituent models within CALIBRE and the associated studies. For example, the inventory data acts as an input to the calculation of the oxidant production rates, which influence the generation of a redox front. The same data is also an initial value data set for the radionuclide migration component of CALIBRE. Similarly, the geometrical parameters of the near-field are common to both sub-models. The principal common parameters are gathered here for ease of reference and avoidance of unnecessary duplication and transcription errors. (au)

  19. Source SDK development essentials

    CERN Document Server

    Bernier, Brett

    2014-01-01

    The Source Authoring Tools are the pieces of software used to create custom content for games made with Valve's Source engine. Creating mods and maps for your games without any programming knowledge can be time consuming. These tools allow you to create your own maps and levels without the need for any coding knowledge. All the tools that you need to start creating your own levels are built-in and ready to go! This book will teach you how to use the Authoring Tools provided with Source games and will guide you in creating your first maps and mods (modifications) using Source. You will learn ho

  20. A Study on Improvement of Algorithm for Source Term Evaluation

    International Nuclear Information System (INIS)

    Park, Jeong Ho; Park, Do Hyung; Lee, Jae Hee

    2010-03-01

    The program developed by KAERI for source term assessment of radwastes from the advanced nuclear fuel cycle consists of spent fuel database analysis module, spent fuel arising projection module, and automatic characterization module for radwastes from pyroprocess. To improve the algorithm adopted the developed program, following items were carried out: - development of an algorithm to decrease analysis time for spent fuel database - development of setup routine for a analysis procedure - improvement of interface for spent fuel arising projection module - optimization of data management algorithm needed for massive calculation to estimate source terms of radwastes from advanced fuel cycle The program developed through this study has a capability to perform source term estimation although several spent fuel assemblies with different fuel design, initial enrichment, irradiation history, discharge burnup, and cooling time are processed at the same time in the pyroprocess. It is expected that this program will be very useful for the design of unit process of pyroprocess and disposal system

  1. Source term estimation for small sized HTRs

    International Nuclear Information System (INIS)

    Moormann, R.

    1992-08-01

    Accidents which have to be considered are core heat-up, reactivity transients, water of air ingress and primary circuit depressurization. The main effort of this paper belongs to water/air ingress and depressurization, which requires consideration of fission product plateout under normal operation conditions; for the latter it is clearly shown, that absorption (penetration) mechanisms are much less important than assumed sometimes in the past. Source term estimation procedures for core heat-up events are shortly reviewed; reactivity transients are apparently covered by them. Besides a general literature survey including identification of areas with insufficient knowledge this paper contains some estimations on the thermomechanical behaviour of fission products in water in air ingress accidents. Typical source term examples are also presented. In an appendix, evaluations of the AVR experiments VAMPYR-I and -II with respect to plateout and fission product filter efficiency are outlined and used for a validation step of the new plateout code SPATRA. (orig.)

  2. H- source developments

    International Nuclear Information System (INIS)

    Allison, P.W.

    1978-01-01

    The design and operation of a Penning discharge, cold cathode, surface plasma H - ion source are described. A high current density, about 2 A/cm 2 , is extracted from the source by putting about 20 keV across the 2 to 2 1 / 2 mm gap

  3. Reevaluation of HFIR source term: Supplement 2

    International Nuclear Information System (INIS)

    Thomas, W.E.

    1986-11-01

    The HFIR source term has been reevaluated to assess the impact of the increase in core lifetime from 15 to 24 days. Calculations were made to determine the nuclide activities of the iodines, noble gases, and other fission products. The results show that there is no significant change in off-site dose due to the increased fuel cycle for the release scenario postulated in ORNL-3573

  4. Open source development

    DEFF Research Database (Denmark)

    Ulhøi, John Parm

    2004-01-01

    This paper addresses innovations based on open source or non-proprietary knowledge. Viewed through the lens of private property theory, such agency appears to be a true anomaly. However, by a further turn of the theoretical kaleidoscope, we will show that there may be perfectly justifiable reasons...... for not regarding open source innovations as anomalies. The paper is based on three sectorial and generic cases of open source innovation, which is an offspring of contemporary theory made possible by combining elements of the model of private agency with those of the model of collective agency. In closing...

  5. Source terms in relation to air cleaning

    International Nuclear Information System (INIS)

    Bernero, R.M.

    1985-01-01

    There are two sets of source terms for consideration in air cleaning, those for routine releases and those for accident releases. With about 1000 reactor years of commercial operating experience in the US done, there is an excellent data base for routine and expected transient releases. Specifications for air cleaning can be based on this body of experience with confidence. Specifications for air cleaning in accident situations is another matter. Recent investigations of severe accident behavior are offering a new basis for source terms and air cleaning specifications. Reports by many experts in the field describe an accident environment notably different from previous models. It is an atmosphere heavy with aerosols, both radioactive and inert. Temperatures are sometimes very high; radioiodine is typically in the form of cesium iodide aerosol particles; other nuclides, such as tellurium, are also important aerosols. Some of the present air cleaning requirements may be very important in light of these new accident behavior models. Others may be wasteful or even counterproductive. The use of the new data on accident behavior models to reevaluate requirements promptly is discussed

  6. Selection of models to calculate the LLW source term

    International Nuclear Information System (INIS)

    Sullivan, T.M.

    1991-10-01

    Performance assessment of a LLW disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). In turn, many of these physical processes are influenced by the design of the disposal facility (e.g., infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This document provides a brief overview of disposal practices and reviews existing source term models as background for selecting appropriate models for estimating the source term. The selection rationale and the mathematical details of the models are presented. Finally, guidance is presented for combining the inventory data with appropriate mechanisms describing release from the disposal facility. 44 refs., 6 figs., 1 tab

  7. Directional Unfolded Source Term (DUST) for Compton Cameras.

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Dean J.; Mitchell, Dean J.; Horne, Steven M.; O' Brien, Sean; Thoreson, Gregory G

    2018-03-01

    A Directional Unfolded Source Term (DUST) algorithm was developed to enable improved spectral analysis capabilities using data collected by Compton cameras. Achieving this objective required modification of the detector response function in the Gamma Detector Response and Analysis Software (GADRAS). Experimental data that were collected in support of this work include measurements of calibration sources at a range of separation distances and cylindrical depleted uranium castings.

  8. Design parameters and source terms: Volume 2, Source terms: Revision 0

    International Nuclear Information System (INIS)

    1987-10-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report by Stearns Catalytic Corporation (SCC), entitled ''Design Parameters and Source Terms for a Two-Phase Repository Salt,'' 1985, to the level of the Site Characterization Plan - Conceptual Design Report. The previous unpublished SCC Study identifies the data needs for the Environmental Assessment effort for seven possible Salt Repository sites. 2 tabs

  9. Design parameters and source terms: Volume 2, Source terms: Revision 0

    International Nuclear Information System (INIS)

    1987-09-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report to the level of the Site Characterization Plan---Conceptual Design Report SCP-CDR. The previous study identifies the data needs for the Environmental Assessment effort for seven possible salt repository sites. Volume 2 contains tables of source terms

  10. Influence of Chemistry on source term assessment

    International Nuclear Information System (INIS)

    Herranz Puebla, L.E.; Lopez Diez, I.; Rodriguez Maroto, J.J.; Martinez Lopez-Alcorocho, A.

    1991-01-01

    The major goal of a phenomenology analysis of containment during a severe accident situation can be splitedd into the following ones: to know the containment response to the different loads and to predict accurately the fission product and aerosol behavior. In this report, the main results coming from the study of a hypothetical accident scenario, based on LA-4 experiment of LACE project, are presented. In order to do it, several codes have been coupled: CONTEMPT4/MOD5 (thermalhydraulics), NAUA/MOD5 (aerosol physics) and IODE (iodine chemistry). 12 refs. It has been demonstrated the impossibility of assessing with confidence the Source Term if the chemical conduct of some radionuclides is not taken into account. In particular, the influence on the iodine retention efficiency of the sump of variables such as pH has been proven. (Author). 12 refs

  11. Flowsheets and source terms for radioactive waste projections

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1985-03-01

    Flowsheets and source terms used to generate radioactive waste projections in the Integrated Data Base (IDB) Program are given. Volumes of each waste type generated per unit product throughput have been determined for the following facilities: uranium mining, UF 6 conversion, uranium enrichment, fuel fabrication, boiling-water reactors (BWRs), pressurized-water reactors (PWRs), and fuel reprocessing. Source terms for DOE/defense wastes have been developed. Expected wastes from typical decommissioning operations for each facility type have been determined. All wastes are also characterized by isotopic composition at time of generation and by general chemical composition. 70 references, 21 figures, 53 tables

  12. Co-sourcing in software development offshoring

    DEFF Research Database (Denmark)

    Schlichter, Bjarne Rerup; Persson, John Stouby

    2013-01-01

    Software development projects are increasingly geographical distributed with offshoring, which introduce complex risks that can lead to project failure. Co-sourcing is a highly integrative and cohesive approach, seen successful, to software development offshoring. However, research of how co-sour......-taking by high attention to of the closely interrelated structure and technology components in terms of CMMI and the actors’ cohesion and integration in terms of Scrum....

  13. Radioactivity source terms for underground engineering application

    Energy Technology Data Exchange (ETDEWEB)

    Tewes, H A [Lawrence Radiation Laboratory, Livermore, CA (United States)

    1969-07-01

    The constraints on nuclide production are usually very similar in any underground engineering application of nuclear explosives. However, in some applications the end product could be contaminated unless the proper nuclear device is used. This fact can be illustrated from two underground engineering experiments-Gasbuggy and Sloop. In the Gasbuggy experiment, appreciable tritium has been shown to be present in the gas currently being produced. However, in future gas stimulation applications (as distinct from experiments), a minimum production of tritium by the explosive is desirable since product contamination by this nuclide may place severe limitations on the use of the tritiated gas. In Sloop, where production of copper is the goal of the experiment, product contamination would not be caused by tritium but could result from other nuclides: Thus, gas stimulation could require the use of fission explosives while the lower cost per kiloton of thermonuclear explosives could make them attractive for ore-crushing applications. Because of this consideration, radionuclide production calculations must be made for both fission and for thermonuclear explosives in the underground environment. Such activation calculations materials of construction are performed in a manner similar to that described in another paper, but radionuclide production in the environment must be computed using both fission neutron and 14-MeV neutron sources in order to treat the 'source term' problem realistically. In making such computations, parameter studies including the effects of environmental temperature, neutron shielding, and rock types have been carried out. Results indicate the importance of carefully evaluating the radionuclide production for each individual underground engineering application. (author)

  14. Radioactivity source terms for underground engineering application

    International Nuclear Information System (INIS)

    Tewes, H.A.

    1969-01-01

    The constraints on nuclide production are usually very similar in any underground engineering application of nuclear explosives. However, in some applications the end product could be contaminated unless the proper nuclear device is used. This fact can be illustrated from two underground engineering experiments-Gasbuggy and Sloop. In the Gasbuggy experiment, appreciable tritium has been shown to be present in the gas currently being produced. However, in future gas stimulation applications (as distinct from experiments), a minimum production of tritium by the explosive is desirable since product contamination by this nuclide may place severe limitations on the use of the tritiated gas. In Sloop, where production of copper is the goal of the experiment, product contamination would not be caused by tritium but could result from other nuclides: Thus, gas stimulation could require the use of fission explosives while the lower cost per kiloton of thermonuclear explosives could make them attractive for ore-crushing applications. Because of this consideration, radionuclide production calculations must be made for both fission and for thermonuclear explosives in the underground environment. Such activation calculations materials of construction are performed in a manner similar to that described in another paper, but radionuclide production in the environment must be computed using both fission neutron and 14-MeV neutron sources in order to treat the 'source term' problem realistically. In making such computations, parameter studies including the effects of environmental temperature, neutron shielding, and rock types have been carried out. Results indicate the importance of carefully evaluating the radionuclide production for each individual underground engineering application. (author)

  15. Fission product source terms and engineered safety features

    International Nuclear Information System (INIS)

    Malinauskas, A.P.

    1984-01-01

    The author states that new, technically defensible, methodologies to establish realistic source term values for nuclear reactor accidents will soon be available. Although these methodologies will undoubtedly find widespread use in the development of accident response procedures, the author states that it is less clear that the industry is preparing to employ the newer results to develop a more rational approach to strategies for the mitigation of fission product releases. Questions concerning the performance of existing engineered safety systems are reviewed

  16. Literature study of source term research for PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Sponton, L.L.; NiIsson, Lars

    2001-04-01

    A literature survey has been carried out in support of ongoing source term calculations with the MELCOR code of some severe accident scenarios for the Swedish Ringhals 2 pressurised water reactor (PWR). The research in the field of severe accidents in power reactors and the source term for subsequent release of radioisotopes was intensified after the Harrisburg accident and has produced a large amount of reports and papers. This survey was therefore limited to research concerning PWR type of reactors and with emphasis on papers related to MELCOR code development. A background is given, relating to some historic documents, and then more recent research after 1990 is reviewed. Of special interest is the ongoing PMbus-programme which is creating new and important results of benefit to the code development and validation of, among others, the MELCOR code. It is concluded that source term calculations involve simulation of many interacting complex physical phenomena, which result in large uncertainties The research has, however, over the years led to considerable improvements Thus has the uncertainty in source term predictions been reduced one to two orders of magnitude from the simpler codes in the early 1980-s to the more realistic codes of today, like MELCOR.

  17. Literature study of source term research for PWRs

    International Nuclear Information System (INIS)

    Sponton, L.L.; NiIsson, Lars

    2001-04-01

    A literature survey has been carried out in support of ongoing source term calculations with the MELCOR code of some severe accident scenarios for the Swedish Ringhals 2 pressurised water reactor (PWR). The research in the field of severe accidents in power reactors and the source term for subsequent release of radioisotopes was intensified after the Harrisburg accident and has produced a large amount of reports and papers. This survey was therefore limited to research concerning PWR type of reactors and with emphasis on papers related to MELCOR code development. A background is given, relating to some historic documents, and then more recent research after 1990 is reviewed. Of special interest is the ongoing PMbus-programme which is creating new and important results of benefit to the code development and validation of, among others, the MELCOR code. It is concluded that source term calculations involve simulation of many interacting complex physical phenomena, which result in large uncertainties The research has, however, over the years led to considerable improvements Thus has the uncertainty in source term predictions been reduced one to two orders of magnitude from the simpler codes in the early 1980-s to the more realistic codes of today, like MELCOR

  18. Source term calculations - Ringhals 2 PWR

    International Nuclear Information System (INIS)

    Johansson, L.L.

    1998-02-01

    This project was performed within the fifth and final phase of sub-project RAK-2.1 of the Nordic Co-operative Reactor Safety Program, NKS.RAK-2.1 has also included studies of reflooding of degraded core, recriticality and late phase melt progression. Earlier source term calculations for Swedish nuclear power plants are based on the integral code MAAP. A need was recognised to compare these calculations with calculations done with mechanistic codes. In the present work SCDAP/RELAP5 and CONTAIN were used. Only limited results could be obtained within the frame of RAK-2.1, since many problems were encountered using the SCDAP/RELAP5 code. The main obstacle was the extremely long execution times of the MOD3.1 version, but also some dubious fission product calculations. However, some interesting results were obtained for the studied sequence, a total loss of AC power. The report describes the modelling approach for SCDAP/RELAP5 and CONTAIN, and discusses results for the transient including the event of a surge line creep rupture. The study will probably be completed later, providing that an improved SCDAP/RELAP5 code version becomes available. (au) becomes available. (au)

  19. 10 CFR 50.67 - Accident source term.

    Science.gov (United States)

    2010-01-01

    ... Conditions of Licenses and Construction Permits § 50.67 Accident source term. (a) Applicability. The... 10 Energy 1 2010-01-01 2010-01-01 false Accident source term. 50.67 Section 50.67 Energy NUCLEAR... to January 10, 1997, who seek to revise the current accident source term used in their design basis...

  20. Hot Hydrogen Heat Source Development

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of this project is to develop a  hot hydrogen heat source that would produce  a high temperature hydrogen flow which would be comparable to that produced...

  1. Recent negative ion source developments

    International Nuclear Information System (INIS)

    Alton, G.D.

    1978-01-01

    This report describes recent results obtained from studies associated with the development of negative ion sources which utilize sputtering in a diffuse cesium plasma as a means of ion beam generation. Data are presented which relate negative ion yield and important operational parameters such as cesium oven temperature and sputter probe voltage from each of the following sources: (1) A source based in principle according to the University of Aarhus design and (2) an axial geometry source. The important design aspects of the sources are given--along with a list of the negative ion intensities observed to date. Also a qualitative description and interpretation of the negative ion generation mechanism in sources which utilize sputtering in the presence of cesium is given

  2. Computer programs for developing source terms for a UF{sub 6} dispersion model to simulate postulated UF{sub 6} releases from buildings

    Energy Technology Data Exchange (ETDEWEB)

    Williams, W.R.

    1985-03-01

    Calculational methods and computer programs for the analysis of source terms for postulated releases of UF{sub 6} are presented. Required thermophysical properties of UF{sub 6}, HF, and H{sub 2}O are described in detail. UF{sub 6} reacts with moisture in the ambient environment to form HF and H{sub 2}O. The coexistence of HF and H{sub 2}O significantly alters their pure component properties, and HF vapor polymerizes. Transient compartment models for simulating UF{sub 6} releases inside gaseous diffusion plant feed and withdrawl buildings and cascade buildings are also described. The basic compartment model mass and energy balances are supported by simple heat transfer, ventilation system, and deposition models. A model that can simulate either a closed compartment or a steady-state ventilation system is also discussed. The transient compartment models provide input to an atmospheric dispersion model as output.

  3. PFLOTRAN-RepoTREND Source Term Comparison Summary.

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, Jennifer M

    2018-03-01

    Code inter-comparison studies are useful exercises to verify and benchmark independently developed software to ensure proper function, especially when the software is used to model high-consequence systems which cannot be physically tested in a fully representative environment. This summary describes the results of the first portion of the code inter-comparison between PFLOTRAN and RepoTREND, which compares the radionuclide source term used in a typical performance assessment.

  4. Design parameters and source terms: Volume 3, Source terms: Revision 0

    International Nuclear Information System (INIS)

    1987-09-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report to the level of the Site Characterization Plan /endash/ Conceptual Design Report, SCP-CDR. The previous unpublished SCC Study identifies the data needs for the Environmental Assessment effort for seven possible salt repository sites

  5. Probabilistic source term predictions for use with decision support systems

    International Nuclear Information System (INIS)

    Grindon, E.; Kinniburgh, C.G.

    2003-01-01

    Full text: Decision Support Systems for use in off-site emergency management, following an incident at a Nuclear Power Plant (NPP) within Europe, are becoming accepted as a useful and appropriate tool to aid decision makers. An area which is not so well developed is the 'upstream' prediction of the source term released into the environment. Rapid prediction of this source term is crucial to the appropriate early management of a nuclear emergency. The initial source term prediction would today be typically based on simple tabulations taking little, or no, account of plant status. It is the interface between the inward looking plant control room team and the outward looking off-site emergency management team that needs to be addressed. This is not an easy proposition as these two distinct disciplines have little common basis from which to communicate their immediate findings and concerns. Within the Euratom Fifth Framework Programme (FP5), complementary approaches are being developed to the pre-release stage; each based on software tools to help bridge this gap. Traditionally source terms (or releases into the environment) provided for use with Decision Support Systems are estimated on a deterministic basis. These approaches use a single, deterministic assumption about plant status. The associated source term represents the 'best estimate' based an available information. No information is provided an the potential for uncertainty in the source term estimate. Using probabilistic methods the outcome is typically a number of possible plant states each with an associated source term and probability. These represent both the best estimate and the spread of the likely source term. However, this is a novel approach and the usefulness of such source term prediction tools is yet to be tested on a wide scale. The benefits of probabilistic source term estimation are presented here; using, as an example, the SPRINT tool developed within the FP5 STERPS project. System for the

  6. Phase 1 immobilized low-activity waste operational source term

    International Nuclear Information System (INIS)

    Burbank, D.A.

    1998-01-01

    This report presents an engineering analysis of the Phase 1 privatization feeds to establish an operational source term for storage and disposal of immobilized low-activity waste packages at the Hanford Site. The source term information is needed to establish a preliminary estimate of the numbers of remote-handled and contact-handled waste packages. A discussion of the uncertainties and their impact on the source term and waste package distribution is also presented. It should be noted that this study is concerned with operational impacts only. Source terms used for accident scenarios would differ due to alpha and beta radiation which were not significant in this study

  7. Ion source and injector development

    International Nuclear Information System (INIS)

    Curtis, C.D.

    1976-01-01

    This is a survey of low energy accelerators which inject into proton linacs. Laboratories covered include Argonne, Brookhaven, CERN, Chalk River, Fermi, ITEP, KEK, Rutherford, and Saclay. This paper emphasizes complete injector systems, comparing significant hardware features and beam performance data, including recent additions. There is increased activity now in the acceleration of polarized protons, H + and H - , and of unpolarized H - . New source development and programs for these ion beams is outlined at the end of the report. Heavy-ion sources are not included

  8. Environmental radiation safety source term evaluation program

    International Nuclear Information System (INIS)

    Moss, O.R.; Filipy, R.E.; Cannon, W.C.; Craig, D.K.

    1977-04-01

    Plutonium-238 is currently used in the form of a pure refractory oxide as a power source on a number of space vehicles that have already been or will be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere and impact with the earth's surface without releasing any plutonium, the possibility of such an event can never be absolutely excluded. Three separate tasks were undertaken in this study. The interactions between soils and 238 PuO 2 aerosols which might be created in a space launch about environment were examined. Aging of the plutonium-soil mixture under a humid atmosphere showed a trend toward the slow coagulation of two dilute aerosols. Studies on marine animals were conducted to assess the response of 238 PuO 2 pellets to conditions found 60 feet below the ocean surface. Ultrafilterability studies measured the solubility of 238 PuO 2 as a function of time, temperature, suspension concentration and molality of solvent

  9. H- radio frequency source development at the Spallation Neutron Source.

    Science.gov (United States)

    Welton, R F; Dudnikov, V G; Gawne, K R; Han, B X; Murray, S N; Pennisi, T R; Roseberry, R T; Santana, M; Stockli, M P; Turvey, M W

    2012-02-01

    The Spallation Neutron Source (SNS) now routinely operates nearly 1 MW of beam power on target with a highly persistent ∼38 mA peak current in the linac and an availability of ∼90%. H(-) beam pulses (∼1 ms, 60 Hz) are produced by a Cs-enhanced, multicusp ion source closely coupled with an electrostatic low energy beam transport (LEBT), which focuses the 65 kV beam into a radio frequency quadrupole accelerator. The source plasma is generated by RF excitation (2 MHz, ∼60 kW) of a copper antenna that has been encased with a thickness of ∼0.7 mm of porcelain enamel and immersed into the plasma chamber. The ion source and LEBT normally have a combined availability of ∼99%. Recent increases in duty-factor and RF power have made antenna failures a leading cause of downtime. This report first identifies the physical mechanism of antenna failure from a statistical inspection of ∼75 antennas which ran at the SNS, scanning electron microscopy studies of antenna surface, and cross sectional cuts and analysis of calorimetric heating measurements. Failure mitigation efforts are then described which include modifying the antenna geometry and our acceptance∕installation criteria. Progress and status of the development of the SNS external antenna source, a long-term solution to the internal antenna problem, are then discussed. Currently, this source is capable of delivering comparable beam currents to the baseline source to the SNS and, an earlier version, has briefly demonstrated unanalyzed currents up to ∼100 mA (1 ms, 60 Hz) on the test stand. In particular, this paper discusses plasma ignition (dc and RF plasma guns), antenna reliability, magnet overheating, and insufficient beam persistence.

  10. COMPASS: A source term code for investigating capillary barrier performance

    International Nuclear Information System (INIS)

    Zhou, Wei; Apted, J.J.

    1996-01-01

    A computer code COMPASS based on compartment model approach is developed to calculate the near-field source term of the High-Level-Waste repository under unsaturated conditions. COMPASS is applied to evaluate the expected performance of Richard's (capillary) barriers as backfills to divert infiltrating groundwater at Yucca Mountain. Comparing the release rates of four typical nuclides with and without the Richard's barrier, it is shown that the Richard's barrier significantly decreases the peak release rates from the Engineered-Barrier-System (EBS) into the host rock

  11. Source term and radiological consequences of the Chernobyl accident

    International Nuclear Information System (INIS)

    Mourad, R.

    1987-09-01

    This report presents the results of a study of the source term and radiological consequences of the Chernobyl accident. The results two parts. The first part was performed during the first 2 months following the accident and dealt with the evaluation of the source term and an estimate of individual doses in the European countries outside the Soviet Union. The second part was performed after August 25-29, 1986 when the Soviets presented in a IAEA Conference in Vienna detailed information about the accident, including source term and radiological consequences in the Soviet Union. The second part of the study reconfirms the source term evaluated in the first part and in addition deals with the radiological consequences in the Soviet Union. Source term and individual doses are calculated from measured post-accident data, reported by the Soviet Union and European countries, microcomputer program PEAR (Public Exposure from Accident Releases). 22 refs

  12. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. 6 refs

  13. Advanced sodium fast reactor accident source terms :

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Dana Auburn; Clement, Bernard; Denning, Richard; Ohno, Shuji; Zeyen, Roland

    2010-09-01

    An expert opinion elicitation has been used to evaluate phenomena that could affect releases of radionuclides during accidents at sodium-cooled fast reactors. The intent was to identify research needed to develop a mechanistic model of radionuclide release for licensing and risk assessment purposes. Experts from the USA, France, the European Union, and Japan identified phenomena that could affect the release of radionuclides under hypothesized accident conditions. They qualitatively evaluated the importance of these phenomena and the need for additional experimental research. The experts identified seven phenomena that are of high importance and have a high need for additional experimental research: High temperature release of radionuclides from fuel during an energetic event Energetic interactions between molten reactor fuel and sodium coolant and associated transfer of radionuclides from the fuel to the coolant Entrainment of fuel and sodium bond material during the depressurization of a fuel rod with breached cladding Rates of radionuclide leaching from fuel by liquid sodium Surface enrichment of sodium pools by dissolved and suspended radionuclides Thermal decomposition of sodium iodide in the containment atmosphere Reactions of iodine species in the containment to form volatile organic iodides. Other issues of high importance were identified that might merit further research as development of the mechanistic model of radionuclide release progressed.

  14. State of the hydrologic source term

    Energy Technology Data Exchange (ETDEWEB)

    Kersting, A.

    1996-12-01

    The Underground Test Area (UGTA) Operable Unit was defined by the U.S. Department of energy, Nevada operations Office to characterize and potentially remediate groundwaters impacted by nuclear testing at the Nevada Test Site (NTS). Between 1955 and 1992, 828 nuclear devices were detonated underground at the NTS (DOE), 1994. Approximately one third of the nuclear tests were detonated at or below the standing water table and the remainder were located above the water table in the vadose zone. As a result, the distribution of radionuclides in the subsurface and, in particular, the availability of radionuclides for transport away from individual test cavities are major concerns at the NTS. The approach taken is to carry out field-based studies of both groundwaters and host rocks within the near-field in order to develop a detailed understanding of the present-day concentration and spatial distribution of constituent radionuclides. Understanding the current distribution of contamination within the near-field and the conditions under and processes by which the radionuclides were transported make it possible to predict future transport behavior. The results of these studies will be integrated with archival research, experiments and geochemical modeling for complete characterization.

  15. Quantification of severe accident source terms of a Westinghouse 3-loop plant

    International Nuclear Information System (INIS)

    Lee Min; Ko, Y.-C.

    2008-01-01

    Integrated severe accident analysis codes are used to quantify the source terms of the representative sequences identified in PSA study. The characteristics of these source terms depend on the detail design of the plant and the accident scenario. A historical perspective of radioactive source term is provided. The grouping of radionuclides in different source terms or source term quantification tools based on TID-14844, NUREG-1465, and WASH-1400 is compared. The radionuclides release phenomena and models adopted in the integrated severe accident analysis codes of STCP and MAAP4 are described. In the present study, the severe accident source terms for risk quantification of Maanshan Nuclear Power Plant of Taiwan Power Company are quantified using MAAP 4.0.4 code. A methodology is developed to quantify the source terms of each source term category (STC) identified in the Level II PSA analysis of the plant. The characteristics of source terms obtained are compared with other source terms. The plant analyzed employs a Westinghouse designed 3-loop pressurized water reactor (PWR) with large dry containment

  16. Source term analyses under severe accidents for KNGR

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yong Mann; Park, Soo Yong

    2001-03-01

    In this study, in-containment source term for LOFW (Loss of Feed Water), which has appeared the most frequent core melt accident, is calculated and compared with NUREG-1465 source term. This study provides not only new source term data using MELCOR1.8.4 and its state-of-the-art models but also evaluating basis of KNGR design and its mitigation capability under severe accidents. As the selected accident is identical with LOFW-S17, which has been analyzed using MAAP by KEPCO with only difference of 2 SITs, mutual comparison of the results is especially expected.

  17. Source term estimation via monitoring data and its implementation to the RODOS system

    International Nuclear Information System (INIS)

    Bohunova, J.; Duranova, T.

    2000-01-01

    A methodology and computer code for interpretation of environmental data, i.e. source term assessment, from on-line environmental monitoring network was developed. The method is based on the conversion of measured dose rates to the source term, i.e. airborne radioactivity release rate, taking into account real meteorological data and location of the monitoring points. The bootstrap estimation methodology and bipivot method to estimate the source term from on-site gamma dose rate monitors is used. The mentioned methods provide an estimate of the mean value of the source term and a confidence interval for it. (author)

  18. Lysimeter data as input to performance assessment source term codes

    International Nuclear Information System (INIS)

    McConnell, J.W. Jr.; Rogers, R.D.; Sullivan, T.

    1992-01-01

    The Field Lysimeter Investigation: Low-Level Waste Data Base Development Program is obtaining information on the performance of radioactive waste in a disposal environment. Waste forms fabricated using ion-exchange resins from EPICOR-II c prefilters employed in the cleanup of the Three Mile Island (TMI) Nuclear Power Station are being tested to develop a low-level waste data base and to obtain information on survivability of waste forms in a disposal environment. In this paper, radionuclide releases from waste forms in the first seven years of sampling are presented and discussed. Application of lysimeter data to be used in performance assessment source term models is presented. Initial results from use of data in two models are discussed

  19. Revised accident source terms and control room habitability

    International Nuclear Information System (INIS)

    Lahti, G.P.; Hubner, R.S.; Johnson, W.J.; Schwartz, B.C.

    1993-01-01

    In April 1992, the NRC staff presented to the Commissioners the draft NUREG open-quotes Revised Accident Source Terms for Light-Water Nuclear Power Plants.close quotes This document is the culmination of more than ten years of NRC-sponsored research and represents the first change in the NRC's position on source terms since TID-14844 was issued in 1962. The purpose of this paper is to investigate the impact of the revised source terms on the current approach to analyzing control room habitability as required by 10 CFR 50. Sample calculations are presented that identify aspects of the model requiring clarification before the implementation of the revised source terms. 6 refs., 4 tabs

  20. The latest results from source term research. Overview and outlook

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, Luis E. [Centro de Investigaciones Energeticas Medio Ambientales y Tecnologica (CIEMAT), Madrid (Spain); Haste, Tim [Centre d' Etudes de Cadarache, Paul-Lez-Durance (France). Institut de Radioprotection et de Surete Nucleaire (IRSN); Kaerkelae, Teemu [VTT Technical Research Centre of Finland Ltd, Espoo (Finland)

    2016-12-15

    Source term research has continued internationally for more than 30 years, increasing confidence in calculations of the potential radioactive release to the environment after a severe reactor accident. Important experimental data have been obtained, mainly under international frameworks such as OECD/NEA and EURATOM. Specifically, Phebus FP provides major insights into fission product release and transport. Results are included in severe accident analysis codes. Data from international projects are being interpreted with a view to further improvements in these codes. This paper synthesizes the recent main outcomes from source term research on these topics, and on source term mitigation. It highlights knowledge gaps remaining and discusses ways to proceed. Aside from this further knowledge-driven research, there is consensus on the need to assess the source term predictive ability of current system codes, taking account of scale-up from experiment to reactor conditions.

  1. Some problems in the categorization of source terms

    International Nuclear Information System (INIS)

    Abbey, F.; Dunbar, I.H.; Hayns, M.R.; Nixon, W.

    1985-01-01

    In recent years techniques for calculating source terms have been considerably improved. It would be unfortunate if the new information were to be blurred by the use of old schemes for the categorization of source terms. In the past categorization schemes have been devised without the question of the general principles of categorization and the available options being addressed explicitly. In this paper these principles are set out, providing a framework within which categorization schemes used in past probabilistic risk assessments and possible future improvements are discussed. In particular the use of input from scoping consequence calculations in deciding how to group source terms, and the question of how modelling uncertainties may be expressed as uncertainties in a final category source terms are considered

  2. Revised accident source terms for light-water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Soffer, L. [Nuclear Regulatory Commission, Washington, DC (United States)

    1995-02-01

    This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

  3. Bayesian source term determination with unknown covariance of measurements

    Science.gov (United States)

    Belal, Alkomiet; Tichý, Ondřej; Šmídl, Václav

    2017-04-01

    Determination of a source term of release of a hazardous material into the atmosphere is a very important task for emergency response. We are concerned with the problem of estimation of the source term in the conventional linear inverse problem, y = Mx, where the relationship between the vector of observations y is described using the source-receptor-sensitivity (SRS) matrix M and the unknown source term x. Since the system is typically ill-conditioned, the problem is recast as an optimization problem minR,B(y - Mx)TR-1(y - Mx) + xTB-1x. The first term minimizes the error of the measurements with covariance matrix R, and the second term is a regularization of the source term. There are different types of regularization arising for different choices of matrices R and B, for example, Tikhonov regularization assumes covariance matrix B as the identity matrix multiplied by scalar parameter. In this contribution, we adopt a Bayesian approach to make inference on the unknown source term x as well as unknown R and B. We assume prior on x to be a Gaussian with zero mean and unknown diagonal covariance matrix B. The covariance matrix of the likelihood R is also unknown. We consider two potential choices of the structure of the matrix R. First is the diagonal matrix and the second is a locally correlated structure using information on topology of the measuring network. Since the inference of the model is intractable, iterative variational Bayes algorithm is used for simultaneous estimation of all model parameters. The practical usefulness of our contribution is demonstrated on an application of the resulting algorithm to real data from the European Tracer Experiment (ETEX). This research is supported by EEA/Norwegian Financial Mechanism under project MSMT-28477/2014 Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling (STRADI).

  4. Development and validation of the aerosol transport module gamma-FP for evaluating radioactive fission product source terms in a VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Churl; Lim, Hong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-12-15

    Predicting radioactive fission product (FP) behaviors in the reactor coolant system and the containment of a nuclear power plant (NPP) is one of the major concerns in the field of reactor safety, since the amount of radioactive FP released into the environment during the postulated accident sequences is one of the major regulatory issues. Radioactive FPs circulating in the primary coolant loop and released into the containment are basically in the form of gas or aerosol. In this study, a multi-component and multi-sectional analysis module for aerosol fission products has been developed based on the MAEROS model, and the aerosol transport model has been developed and verified against an analytic solution. The deposition of aerosol FPs to the surrounding structural surfaces is modeled with recent research achievements. The developed aerosol analysis model has been successfully validated against the STORM SR-11 experimental data, which is International Standard Problem No. 40. Future studies include the development of the resuspension, growth, and chemical reaction models of aerosol fission products.

  5. The EC CAST project (carbon-14 source term)

    International Nuclear Information System (INIS)

    Williams, S. J.

    2015-01-01

    Carbon-14 is a key radionuclide in the assessment of the safety of underground geological disposal facilities for radioactive wastes. It is possible for carbon-14 to be released from waste packages in a variety of chemical forms, both organic and inorganic, and as dissolved or gaseous species The EC CAST (CArbon-14 Source Term) project aims to develop understanding of the generation and release of carbon-14 from radioactive waste materials under conditions relevant to packaging and disposal. It focuses on the release of carbon-14 from irradiated metals (steels and zirconium alloys), from irradiated graphite and from spent ion-exchange resins. The CAST consortium brings together 33 partners. CAST commenced in October 2013 and this paper describes progress to March 2015. The main activities during this period were reviews of the current status of knowledge, the identification and acquisition of suitable samples and the design of experiments and analytical procedures. (authors)

  6. Utility view of the source term and air cleaning

    International Nuclear Information System (INIS)

    Littlefield, P.S.

    1985-01-01

    The utility view of the source term and air cleaning is discussed. The source term is made up of: (1) noble gases, which there has been a tendency to ignore in the past because it was thought there was nothing that could be done with them anyway, (2) the halogens, which have been dealt with in Air Cleaning Conferences in the past in terms of charcoal and other systems for removing them, and (3) the solid components of the source term which particulate filters are designed to handle. Air cleaning systems consist of filters, adsorbers, containment sprays, suppression pools in boiling water reactors and ice beds in ice condenser-equipped plants. The feasibility and cost of air cleaning systems are discussed

  7. Management of development of renewable energy sources

    Directory of Open Access Journals (Sweden)

    Inić Branimir P.

    2014-01-01

    Full Text Available The aim of the paper: 'Management of development of renewable energy sources is to point out the possible solutions for neutralizing the threat of energy shortages. The paper outlines major short and long term energy problems facing humanity. The increase of world human population is, inevitably, accompanied by higher energy consumption. Reserves decrease of nonrenewable energy sources like oil, gas, and coal is a major threat to maintaining current living conditions, and thus requires solutions in order to neutralize the threat. This is why the management of development of renewable energy sources is an imperative for Serbia. The paper emphasizes the use of solar energy, because the annual average of solar radiation in Serbia is about 40% higher than the European average, however, the actual use of the sun's energy to generate electricity in Serbia is far behind the countries of the European Union. Solar energy is clean, renewable, and the fact that 4.2 kilowatt-hours are received daily per square meter averaged over the entire surface of the planet, makes it an almost unused energy source, Compared to EU countries, the price of non-renewable derived energy is, on average, higher in Serbia. Taking this into consideration, the use of solar energy, as an unused resource, imposes itself as indispensable.

  8. Low-level radioactive waste performance assessments: Source term modeling

    International Nuclear Information System (INIS)

    Icenhour, A.S.; Godbee, H.W.; Miller, L.F.

    1995-01-01

    Low-level radioactive wastes (LLW) generated by government and commercial operations need to be isolated from the environment for at least 300 to 500 yr. Most existing sites for the storage or disposal of LLW employ the shallow-land burial approach. However, the U.S. Department of Energy currently emphasizes the use of engineered systems (e.g., packaging, concrete and metal barriers, and water collection systems). Future commercial LLW disposal sites may include such systems to mitigate radionuclide transport through the biosphere. Performance assessments must be conducted for LUW disposal facilities. These studies include comprehensive evaluations of radionuclide migration from the waste package, through the vadose zone, and within the water table. Atmospheric transport mechanisms are also studied. Figure I illustrates the performance assessment process. Estimates of the release of radionuclides from the waste packages (i.e., source terms) are used for subsequent hydrogeologic calculations required by a performance assessment. Computer models are typically used to describe the complex interactions of water with LLW and to determine the transport of radionuclides. Several commonly used computer programs for evaluating source terms include GWSCREEN, BLT (Breach-Leach-Transport), DUST (Disposal Unit Source Term), BARRIER (Ref. 5), as well as SOURCE1 and SOURCE2 (which are used in this study). The SOURCE1 and SOURCE2 codes were prepared by Rogers and Associates Engineering Corporation for the Oak Ridge National Laboratory (ORNL). SOURCE1 is designed for tumulus-type facilities, and SOURCE2 is tailored for silo, well-in-silo, and trench-type disposal facilities. This paper focuses on the source term for ORNL disposal facilities, and it describes improved computational methods for determining radionuclide transport from waste packages

  9. Review of SFR In-Vessel Radiological Source Term Studies

    International Nuclear Information System (INIS)

    Suk, Soo Dong; Lee, Yong Bum

    2008-10-01

    An effort has been made in this study to search for and review the literatures in public domain on the studies of the phenomena related to the release of radionuclides and aerosols to the reactor containment of the sodium fast reactor (SFR) plants (i.e., in-vessel source term), made in Japan and Europe including France, Germany and UK over the last few decades. Review work is focused on the experimental programs to investigate the phenomena related to determining the source terms, with a brief review on supporting analytical models and computer programs. In this report, the research programs conducted to investigate the CDA (core disruptive accident) bubble behavior in the sodium pool for determining 'primary' or 'instantaneous' source term are first introduced. The studies performed to determine 'delayed source term' are then described, including the various stages of phenomena and processes: fission product (FP) release from fuel , evaporation release from the surface of the pool, iodine mass transfer from fission gas bubble, FP deposition , and aerosol release from core-concrete interaction. The research programs to investigate the release and transport of FPs and aerosols in the reactor containment (i.e., in-containment source term) are not described in this report

  10. Source term identification in atmospheric modelling via sparse optimization

    Science.gov (United States)

    Adam, Lukas; Branda, Martin; Hamburger, Thomas

    2015-04-01

    Inverse modelling plays an important role in identifying the amount of harmful substances released into atmosphere during major incidents such as power plant accidents or volcano eruptions. Another possible application of inverse modelling lies in the monitoring the CO2 emission limits where only observations at certain places are available and the task is to estimate the total releases at given locations. This gives rise to minimizing the discrepancy between the observations and the model predictions. There are two standard ways of solving such problems. In the first one, this discrepancy is regularized by adding additional terms. Such terms may include Tikhonov regularization, distance from a priori information or a smoothing term. The resulting, usually quadratic, problem is then solved via standard optimization solvers. The second approach assumes that the error term has a (normal) distribution and makes use of Bayesian modelling to identify the source term. Instead of following the above-mentioned approaches, we utilize techniques from the field of compressive sensing. Such techniques look for a sparsest solution (solution with the smallest number of nonzeros) of a linear system, where a maximal allowed error term may be added to this system. Even though this field is a developed one with many possible solution techniques, most of them do not consider even the simplest constraints which are naturally present in atmospheric modelling. One of such examples is the nonnegativity of release amounts. We believe that the concept of a sparse solution is natural in both problems of identification of the source location and of the time process of the source release. In the first case, it is usually assumed that there are only few release points and the task is to find them. In the second case, the time window is usually much longer than the duration of the actual release. In both cases, the optimal solution should contain a large amount of zeros, giving rise to the

  11. Actinide Source Term Program, position paper. Revision 1

    International Nuclear Information System (INIS)

    Novak, C.F.; Papenguth, H.W.; Crafts, C.C.; Dhooge, N.J.

    1994-01-01

    The Actinide Source Term represents the quantity of actinides that could be mobilized within WIPP brines and could migrate with the brines away from the disposal room vicinity. This document presents the various proposed methods for estimating this source term, with a particular focus on defining these methods and evaluating the defensibility of the models for mobile actinide concentrations. The conclusions reached in this document are: the 92 PA open-quotes expert panelclose quotes model for mobile actinide concentrations is not defensible; and, although it is extremely conservative, the open-quotes inventory limitsclose quotes model is the only existing defensible model for the actinide source term. The model effort in progress, open-quotes chemical modeling of mobile actinide concentrationsclose quotes, supported by a laboratory effort that is also in progress, is designed to provide a reasonable description of the system and be scientifically realistic and supplant the open-quotes Inventory limitsclose quotes model

  12. Determination of source term for Krsko NPP extended fuel cycle

    International Nuclear Information System (INIS)

    Nemec, T.; Persic, A.; Zagar, T.; Zefran, B.

    2004-01-01

    The activity and composition of the potential radioactive releases (source term) is important in the decision making about off-site emergency measures in case of a release into environment. Power uprate of Krsko NPP during modernization in 2000 as well as changing of the fuel type and the core design have influenced the source term value. In 2003 a project of 'Jozef Stefan' Institute and Slovenian nuclear safety administration determined a plantspecific source term for new conditions of fuel type and burnup for extended fuel cycle. Calculations of activity and isotopic composition of the core have been performed with ORIGEN-ARP program. Results showed that the core activity for extended 15 months fuel cycle is slightly lower than for the 12 months cycles, mainly due to larger share of fresh fuel. (author)

  13. Techniques for long term conditioning and storage of radium sources

    International Nuclear Information System (INIS)

    Dogaru, Gheorghe; Dragolici, Felicia; Nicu, Mihaela

    2008-01-01

    The Horia Hulubei National Institute of Research and Development for Physics and Nuclear Engineering developed its own technology for conditioning the radium spent sealed radioactive sources. The laboratory dedicated to radiological characterization, identification of radium sources as well as the encapsulation of spent sealed radioactive sources was equipped with a local ventilation system, welding devices, tightness test devices as well as radiometric portable devices. Two types of capsules have been designed for conditioning of radium spent sealed radioactive sources. For these kinds of capsules different types of storage packaging were developed. Data on the radium inventory will be presented in the paper. The paper contains the description of the process of conditioning of spent sealed radioactive sources as well as the description of the capsules and packaging. The paper describes the equipment used for the conditioning of the radium spent sealed sources. (authors)

  14. Spallation Neutron Source Accident Terms for Environmental Impact Statement Input

    Energy Technology Data Exchange (ETDEWEB)

    Devore, J.R.; Harrington, R.M.

    1998-08-01

    This report is about accidents with the potential to release radioactive materials into the environment surrounding the Spallation Neutron Source (SNS). As shown in Chap. 2, the inventories of radioactivity at the SNS are dominated by the target facility. Source terms for a wide range of target facility accidents, from anticipated events to worst-case beyond-design-basis events, are provided in Chaps. 3 and 4. The most important criterion applied to these accident source terms is that they should not underestimate potential release. Therefore, conservative methodology was employed for the release estimates. Although the source terms are very conservative, excessive conservatism has been avoided by basing the releases on physical principles. Since it is envisioned that the SNS facility may eventually (after about 10 years) be expanded and modified to support a 4-MW proton beam operational capability, the source terms estimated in this report are applicable to a 4-MW operating proton beam power unless otherwise specified. This is bounding with regard to the 1-MW facility that will be built and operated initially. See further discussion below in Sect. 1.2.

  15. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. Volume 3 is a compilation of appendices giving detailed results of the study

  16. ITER Safety Task NID-5A, Subtask 1-1: Source terms and energies - initial tritium source terms. Final report

    International Nuclear Information System (INIS)

    Fong, C.; Kalyanam, K.M.; Tanaka, M.R.; Sood, S.; Natalizio, A.; Delisle, M.

    1995-02-01

    The overall objective of the Early Safety and Environmental Characterization Study (ESECS) is to assess the environmental impact of tritium using appropriate assumptions on a hypothetical site for ITER, having the r eference s ite characteristics as proposed by the JCT. The objective of this work under the above subtask 1-1, NID-5a, is to determine environmental source terms (i.e., process source term x containment release fraction) for the fuel cycle and cooling systems. The work is based on inventories and process source terms (i.e., inventory x mobilization fraction), provided by others (under Task NID 3b). The results of this work form the basis for the determination, by others, of the off-site dose (i.e., environmental source term x dose/release ratio). For the determination of the environmental source terms, the TMAP4 code has been utilized (ref 1). This code is approved by ITER for safety assessment. Volume 2 is a compilation of appendices giving detailed results of the study. 5 figs

  17. STACE: Source Term Analyses for Containment Evaluations of transport casks

    International Nuclear Information System (INIS)

    Seager, K.D.; Gianoulakis, S.E.; Barrett, P.R.; Rashid, Y.R.; Reardon, P.C.

    1992-01-01

    Following the guidance of ANSI N14.5, the STACE methodology provides a technically defensible means for estimating maximum permissible leakage rates. These containment criteria attempt to reflect the true radiological hazard by performing a detailed examination of the spent fuel, CRUD, and residual contamination contributions to the releasable source term. The evaluation of the spent fuel contribution to the source term has been modeled fairly accurately using the STACE methodology. The structural model predicts the cask drop load history, the mechanical response of the fuel assembly, and the probability of cladding breach. These data are then used to predict the amount of fission gas, volatile species, and fuel fines that are releasable from the cask. There are some areas where data are sparse or lacking (e.g., the quantity and size distribution of fuel rod breaches) in which experimental validation is planned. The CRUD spallation fraction is the major area where no quantitative data has been found; therefore, this also requires experimental validation. In the interim, STACE conservatively assumes a 100% spallation fraction for computing the releasable activity. The source term methodology also conservatively assumes that there is 1 Ci of residual contamination available for release in the transport cask. However, residual contamination is still by far the smallest contributor to the source term activity

  18. Fission product source term research at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Malinauskas, A.P.

    1985-01-01

    The purpose of this work is to describe some of the research being performed at ORNL in support of the effort to describe, as realistically as possible, fission product source terms for nuclear reactor accidents. In order to make this presentation manageable, only those studies directly concerned with fission product behavior, as opposed to thermal hydraulics, accident sequence progression, etc., will be discussed

  19. Renewable energy sources for tenable development

    International Nuclear Information System (INIS)

    Manazza, G.

    1992-01-01

    Planning criteria for feasible tenable development strategies for industrialized and developing countries are discussed. Attention is given to the role to be played by industrial countries in renewable energy source development and technology transfer to curb the onslaught of global greenhouse effects related environmental problems. The paper cautions against the use of the expression 'tenable' in combination with 'growth'. It recommends, instead, the substitution of the expression, 'tenable growth', which implies the indefinite growth of something which is physical, with 'tenable development', a preferred term, since it denotes the realization of an optimum strategy, compatible with environmental ecosystems, for the betterment of living conditions. An assessment is made of the overall social-economic impacts of such a strategy on the proposed European free trade market and on developing countries struggling to survive in a fiercely competitive world. Here, the paper notes that, for the effective implementation of a tenable development strategy, it is of prime importance to make optimum use of the education system to instil a new set of social values and modify individual behaviour relative to the development and use of natural resources

  20. High power microwave source development

    Science.gov (United States)

    Benford, James N.; Miller, Gabriel; Potter, Seth; Ashby, Steve; Smith, Richard R.

    1995-05-01

    The requirements of this project have been to: (1) improve and expand the sources available in the facility for testing purposes and (2) perform specific tasks under direction of the Defense Nuclear Agency about the applications of high power microwaves (HPM). In this project the HPM application was power beaming. The requirements of this program were met in the following way: (1) We demonstrated that a compact linear induction accelerator can drive HPM sources at repetition rates in excess of 100 HZ at peak microwave powers of a GW. This was done for the relativistic magnetron. Since the conclusion of this contract such specifications have also been demonstrated for the relativistic klystron under Ballistic Missile Defense Organization funding. (2) We demonstrated an L band relativistic magnetron. This device has been used both on our single pulse machines, CAMEL and CAMEL X, and the repetitive system CLIA. (3) We demonstrated that phase locking of sources together in large numbers is a feasible technology and showed the generation of multigigawatt S-band radiation in an array of relativistic magnetrons.

  1. Reassessment of the technical bases for estimating source terms. Draft report for comment

    International Nuclear Information System (INIS)

    Silberberg, M.; Mitchell, J.A.; Meyer, R.O.; Pasedag, W.F.; Ryder, C.P.; Peabody, C.A.; Jankowski, M.W.

    1985-07-01

    NUREG-0956 describes the NRC staff and contractor efforts to reassess and update the agency's analytical procedures for estimating accident source terms for nuclear power plants. The effort included development of a new source term analytical procedure - a set of computer codes - that is intended to replace the methodology of the Reactor Safety Study (WASH-1400) and to be used in reassessing the use of TID-14844 assumptions (10 CFR 100). NUREG-0956 describes the development of these codes, the demonstration of the codes to calculate source terms for specific cases, the peer review of this work, some perspectives on the overall impact of new source terms on plant risks, the plans for related research projects, and the conclusions and recommendations resulting from the effort

  2. Application of the source term code package to obtain a specific source term for the Laguna Verde Nuclear Power Plant

    International Nuclear Information System (INIS)

    Souto, F.J.

    1991-06-01

    The main objective of the project was to use the Source Term Code Package (STCP) to obtain a specific source term for those accident sequences deemed dominant as a result of probabilistic safety analyses (PSA) for the Laguna Verde Nuclear Power Plant (CNLV). The following programme has been carried out to meet this objective: (a) implementation of the STCP, (b) acquisition of specific data for CNLV to execute the STCP, and (c) calculations of specific source terms for accident sequences at CNLV. The STCP has been implemented and validated on CDC 170/815 and CDC 180/860 main frames as well as on a Micro VAX 3800 system. In order to get a plant-specific source term, data on the CNLV including initial core inventory, burn-up, primary containment structures, and materials used for the calculations have been obtained. Because STCP does not explicitly model containment failure, dry well failure in the form of a catastrophic rupture has been assumed. One of the most significant sequences from the point of view of possible off-site risk is the loss of off-site power with failure of the diesel generators and simultaneous loss of high pressure core spray and reactor core isolation cooling systems. The probability for that event is approximately 4.5 x 10 -6 . This sequence has been analysed in detail and the release fractions of radioisotope groups are given in the full report. 18 refs, 4 figs, 3 tabs

  3. Impact of source terms on distances to which reactor accident consequences occur

    International Nuclear Information System (INIS)

    Ostmeyer, R.M.

    1982-01-01

    Estimates of the distances over which reactor accident consequences might occur are important for development of siting criteria and for emergency response planning. This paper summarizes the results of a series of CRAC2 calculations performed to estimate these distances. Because of the current controversy concerning the magnitude of source terms for severe accidents, the impact of source term reductions upon distance estimates is also examined

  4. Usability in open source software development

    DEFF Research Database (Denmark)

    Andreasen, M. S.; Nielsen, H. V.; Schrøder, S. O.

    2006-01-01

    Open Source Software (OSS) development has gained significant importance in the production of soft-ware products. Open Source Software developers have produced systems with a functionality that is competitive with similar proprietary software developed by commercial software organizations. Yet OSS...

  5. Using Bayesian Belief Network (BBN) modelling for Rapid Source Term Prediction. RASTEP Phase 1

    International Nuclear Information System (INIS)

    Knochenhauer, M.; Swaling, V.H.; Alfheim, P.

    2012-09-01

    The project is connected to the development of RASTEP, a computerized source term prediction tool aimed at providing a basis for improving off-site emergency management. RASTEP uses Bayesian belief networks (BBN) to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, timing, and pathway of released radio-nuclides). The output is a set of possible source terms with associated probabilities. In the NKS project, a number of complex issues associated with the integration of probabilistic and deterministic analyses are addressed. This includes issues related to the method for estimating source terms, signal validation, and sensitivity analysis. One major task within Phase 1 of the project addressed the problem of how to make the source term module flexible enough to give reliable and valid output throughout the accident scenario. Of the alternatives evaluated, it is recommended that RASTEP is connected to a fast running source term prediction code, e.g., MARS, with a possibility of updating source terms based on real-time observations. (Author)

  6. Using Bayesian Belief Network (BBN) modelling for Rapid Source Term Prediction. RASTEP Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Knochenhauer, M.; Swaling, V.H.; Alfheim, P. [Scandpower AB, Sundbyberg (Sweden)

    2012-09-15

    The project is connected to the development of RASTEP, a computerized source term prediction tool aimed at providing a basis for improving off-site emergency management. RASTEP uses Bayesian belief networks (BBN) to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, timing, and pathway of released radio-nuclides). The output is a set of possible source terms with associated probabilities. In the NKS project, a number of complex issues associated with the integration of probabilistic and deterministic analyses are addressed. This includes issues related to the method for estimating source terms, signal validation, and sensitivity analysis. One major task within Phase 1 of the project addressed the problem of how to make the source term module flexible enough to give reliable and valid output throughout the accident scenario. Of the alternatives evaluated, it is recommended that RASTEP is connected to a fast running source term prediction code, e.g., MARS, with a possibility of updating source terms based on real-time observations. (Author)

  7. Current status of ion source development

    International Nuclear Information System (INIS)

    Ishikawa, Junzo

    2001-01-01

    In this report, the current status of ion source development will be discussed. In September 2001, the 9th International Conference on Ion Sources (ICIS01) was held in Oakland, U.S.A. Referring the talks presented at ICIS01, recent topics in the ion source research fields will be described. (author)

  8. A nuclear source term analysis for spacecraft power systems

    International Nuclear Information System (INIS)

    McCulloch, W.H.

    1998-01-01

    All US space missions involving on board nuclear material must be approved by the Office of the President. To be approved the mission and the hardware systems must undergo evaluations of the associated nuclear health and safety risk. One part of these evaluations is the characterization of the source terms, i.e., the estimate of the amount, physical form, and location of nuclear material, which might be released into the environment in the event of credible accidents. This paper presents a brief overview of the source term analysis by the Interagency Nuclear Safety Review Panel for the NASA Cassini Space Mission launched in October 1997. Included is a description of the Energy Interaction Model, an innovative approach to the analysis of potential releases from high velocity impacts resulting from launch aborts and reentries

  9. Estimation of Source terms for Emergency Planning and Preparedness

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Chul Un; Chung, Bag Soon; Ahn, Jae Hyun; Yoon, Duk Ho; Jeong, Chul Young; Lim, Jong Dae [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Kang, Sun Gu; Suk, Ho; Park, Sung Kyu; Lim, Hac Kyu; Lee, Kwang Nam [Korea Power Engineering Company Consulting and Architecture Engineers, (Korea, Republic of)

    1997-12-31

    In this study the severe accident sequences for each plant of concern, which represent accident sequences with a high core damage frequency and significant accident consequences, were selected based on the results of probabilistic safety assessments and source term and time-histories of various safety parameters under severe accidents. Accidents progression analysis for each selected accident sequence was performed by MAAP code. It was determined that the measured values, dose rate and radioisotope concentration, could provide information to the operators on occurrence and timing of core damage, reactor vessel failure, and containment failure during severe accidents. Radioactive concentration in the containment atmosphere, which may be measured by PASS, was estimated. Radioisotope concentration in emergency planning, evaluation of source term behavior in the containment, estimation of core damage degree, analysis of severe accident phenomena, core damage timing, and the amount of radioisotope released to the environment. (author). 50 refs., 60 figs.

  10. Realistic minimum accident source terms - Evaluation, application, and risk acceptance

    International Nuclear Information System (INIS)

    Angelo, P. L.

    2009-01-01

    The evaluation, application, and risk acceptance for realistic minimum accident source terms can represent a complex and arduous undertaking. This effort poses a very high impact to design, construction cost, operations and maintenance, and integrated safety over the expected facility lifetime. At the 2005 Nuclear Criticality Safety Division (NCSD) Meeting in Knoxville Tenn., two papers were presented mat summarized the Y-12 effort that reduced the number of criticality accident alarm system (CAAS) detectors originally designed for the new Highly Enriched Uranium Materials Facility (HEUMF) from 258 to an eventual as-built number of 60. Part of that effort relied on determining a realistic minimum accident source term specific to the facility. Since that time, the rationale for an alternate minimum accident has been strengthened by an evaluation process that incorporates realism. A recent update to the HEUMF CAAS technical basis highlights the concepts presented here. (authors)

  11. Considerations about source term now used aiming to emergency planning

    International Nuclear Information System (INIS)

    Austregesilo Filho, H.

    1987-01-01

    The applicability of source terms, in parametric studies for improving external emergengy plan for Angra-I reactor is presented. The source term is defined as, the quantity and radioactive material disposable for releasing to the environment in case of austere accident in a nuclear power plant. The following hypothesis: occuring accident, 100% of the noble gases, 50% of halogens and 1% of solid fission products contained into the reactor core, are released immediately toward the containment building; the radioactivity releasing to the environment is done at a constant rate of 0.1% in mass per day; the actuation of mitigated systems of radioactivity releasing, such as, spray of container or system of air recirculation by filters, is not considered; and the releasing is done at soil level. (M.C.K.) [pt

  12. Development of cold neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Oong; Cho, M. S.; Park, K. N. and others

    1999-05-01

    The purpose of this study is to develop the CNS facility in Hanaro to extend the scope of the neutron utilization and to carry out the works impossible by thermal neutrons. According to the project schedule, the establishment of the CNS concept and the basic design are performed in the phase 1, and the elementary technologies for basic design will be developed in the phase 2. Finally in the phase 3, the design of CNS will be completed, and the fabrication, the installation will be ended and then the development plan of spectrometers will be decided to establish the foothold to carry out the basic researches. This study is aimed to produce the design data and utilize them in the future basic and detail design, which include the estimation and the measurement of the heat load, the code development for the design of the in pile assembly and the heat removal system, the measurement of the shape of the CN hole, the performance test of thermosiphon and the concept of the general layout of the whole system etc.. (author)

  13. Basic repository source term and data sheet report: Lavender Canyon

    International Nuclear Information System (INIS)

    1988-01-01

    This report is one of a series describing studies undertaken in support of the US Department of Energy Civilian Radioactive Waste Management (CRWM) Program. This study contains the derivation of values for environmental source terms and resources consumed for a CRWM repository. Estimates include heavy construction equipment; support equipment; shaft-sinking equipment; transportation equipment; and consumption of fuel, water, electricity, and natural gas. Data are presented for construction and operation at an assumed site in Lavender Canyon, Utah. 3 refs; 6 tabs

  14. Basic repository source term and data sheet report: Davis Canyon

    International Nuclear Information System (INIS)

    1988-01-01

    This report is one of series describing studies undertaken in support of the US Department of Energy Civilian Radioactive Waste Management (CRWM) Program. This study contains the derivation of values for environmental source terms and resources consumed for a CRWM repository. Estimates include heavy construction equipment; support equipment; shaft-sinking equipment; transportation equipment; and consumption of fuel, water electricity, and natural gas. Data are presented for construction and operation at an assumed site in Davis Canyon, Utah. 6 tabs

  15. Introduction: Long term economic development

    DEFF Research Database (Denmark)

    Pyka, Andreas; Andersen, Esben Sloth

    2012-01-01

    The general theme of the 13th International Joseph A. Schumpeter Society Conference, held during June 21st–24th, 2010 at Aalborg University in Denmark, was the exploration of the interrelated phenomena of innovation, organization, sustainability and crises. By addressing these phenomena an attemp...... was made to confront some of the underexplored parts the Schumpeterian legacy, but there was also room for new results concerning more well-developed parts of evolutionary economics....

  16. Source terms for airborne radioactivity arising from uranium mill wastes

    International Nuclear Information System (INIS)

    O'Riordan, M.C.; Downing, A.L.

    1978-01-01

    One of the problems in assessing the radiological impact of uranium milling is to determine the rates of release to the air of material from the various sources of radioactivity. Such source terms are required for modelling the transport of radioactive material in the atmosphere. Activity arises from various point and area sources in the mill itself and from the mill tailings. The state of the tailings changes in time from slurry to solid. A layer of water may be maintained over the solids during the life of the mine, and the tailings may be covered with inert material on abandonment. Releases may be both gaseous and particulate. This paper indicates ways in which radon emanation and the suspension of long-lived particulate activity might be quantified, and areas requiring further exploration are identified

  17. Accident source terms for boiling water reactors with high burnup cores.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Leonard, Mark Thomas

    2007-11-01

    The primary objective of this report is to provide the technical basis for development of recommendations for updates to the NUREG-1465 Source Term for BWRs that will extend its applicability to accidents involving high burnup (HBU) cores. However, a secondary objective is to re-examine the fundamental characteristics of the prescription for fission product release to containment described by NUREG-1465. This secondary objective is motivated by an interest to understand the extent to which research into the release and behaviors of radionuclides under accident conditions has altered best-estimate calculations of the integral response of BWRs to severe core damage sequences and the resulting radiological source terms to containment. This report, therefore, documents specific results of fission product source term analyses that will form the basis for the HBU supplement to NUREG-1465. However, commentary is also provided on observed differences between the composite results of the source term calculations performed here and those reflected NUREG-1465 itself.

  18. Data assimilation and source term estimation during the early phase of a nuclear accident

    Energy Technology Data Exchange (ETDEWEB)

    Golubenkov, A.; Borodin, R. [SPA Typhoon, Emergency Centre (Russian Federation); Sohier, A.; Rojas Palma, C. [Centre de l`Etude de l`Energie Nucleaire, Mol (Belgium)

    1996-02-01

    The mathematical/physical base of possible methods to model the source term during an accidental release of radionuclides is discussed. Knowledge of the source term is important in view of optimizing urgent countermeasures to the population. In most cases however, it will be impossible to assess directly the release dynamics. Therefore methods are under development in which the source term is modelled, based on the comparison of off-site monitoring data and model predictions using an atmospheric dispersion model. The degree of agreement between the measured and calculated characteristics of the radioactive contamination of the air and the ground surface is an important criterion in this process. Due to the inherent complexity, some geometrical transformations taking space-time discrepancies between observed and modelled contamination fields are defined before the source term is adapted. This work describes the developed algorithms which are also tested against data from some tracer experiments performed in the past. This method is also used to reconstruct the dynamics of the Chernobyl source term. Finally this report presents a concept of software to reconstruct a multi-isotopic source term in real-time.

  19. Data assimilation and source term estimation during the early phase of a nuclear accident

    International Nuclear Information System (INIS)

    Golubenkov, A.; Borodin, R.; Sohier, A.; Rojas Palma, C.

    1996-02-01

    The mathematical/physical base of possible methods to model the source term during an accidental release of radionuclides is discussed. Knowledge of the source term is important in view of optimizing urgent countermeasures to the population. In most cases however, it will be impossible to assess directly the release dynamics. Therefore methods are under development in which the source term is modelled, based on the comparison of off-site monitoring data and model predictions using an atmospheric dispersion model. The degree of agreement between the measured and calculated characteristics of the radioactive contamination of the air and the ground surface is an important criterion in this process. Due to the inherent complexity, some geometrical transformations taking space-time discrepancies between observed and modelled contamination fields are defined before the source term is adapted. This work describes the developed algorithms which are also tested against data from some tracer experiments performed in the past. This method is also used to reconstruct the dynamics of the Chernobyl source term. Finally this report presents a concept of software to reconstruct a multi-isotopic source term in real-time

  20. New developments with H-sources

    International Nuclear Information System (INIS)

    Sherman, Joseph D.; Rouleau, G.

    2002-01-01

    Existing spallation neutron source upgrades, planned spallation neutron sources, and high-energy accelerators for particle physics place demanding requirements on the Hsources. These requirements ask for increased beam currents and duty factor (df) while generally maintaining state-of-the art H' source emittance. A variety of H sources are being developed to address these challenges. These include volume sources with and without the addition of cesium for enhanced He production, increased df cesiated H' Penning and magnetron sources, and cesiated surface converter H- sources. Research on surface films of tantalum metal for enhanced volume H- production is also being studied. Innovative plasma production techniques to address the longer df requirement without sacrificing H- source reliability and liktime will be reviewed. The physical bases, the goals, and perceived challenges will be discussed.

  1. The influence of source term release parameters on health effects

    International Nuclear Information System (INIS)

    Jeong, Jong Tae; Ha, Jae Joo

    1998-08-01

    In this study, the influence of source term release parameters on the health effects was examined. This is very useful in identifying the relative importance of release parameters and can be an important factor in developing a strategy for reducing offsite risks. The release parameters investigated in this study are release height, heat content, fuel burnup, release time, release duration, and warning time. The health effects affected by the change of release parameters are early fatalities, cancer fatalities, early injuries, cancer injuries, early fatality risk, population weighted early fatality risk, population weighted cancer fatality risk, effective whole body population dose, population exceeding an early acute red bone marrow dose of 1.5 Sv, and distance at which early fatalities are expected to occur. As release height increases, the values of early health effects such as early fatalities and injuries decrease. However, the release height dose not have significant influences on late health effects. The values of both early and late health effects decrease as heat content increases. The increase fuel burnup, i.e., the increase of core inventories increases the late health effects, however, has small influence on the early health effects. But, the number of early injuries increases as the fuel burnup increases. The effects of release time increase shows very similar influence on both the early and late health effects. As the release time increases to 2 hours, the values of health effects increase and then decrease rapidly. As release duration increases, the values of late health effects increase slightly, however, the values of early health effects decrease. As warning time increases to 2 hours, the values of late health effects decrease and then shows no variation. The number of early injuries decreases rapidly as the warning time increases to 2 hours. However, the number of early fatalities and the early fatality risk increase as the warning time increases

  2. High current ion source development at Frankfurt

    Energy Technology Data Exchange (ETDEWEB)

    Volk, K.; Klein, H.; Lakatos, A.; Maaser, A.; Weber, M. [Frankfurt Univ. (Germany). Inst. fuer Angewandte Physik

    1995-11-01

    The development of high current positive and negative ion sources is an essential issue for the next generation of high current linear accelerators. Especially, the design of the European Spallation Source facility (ESS) and the International Fusion Material Irradiation Test Facility (IFMIF) have increased the significance of high brightness hydrogen and deuterium sources. As an example, for the ESS facility, two H{sup -}-sources each delivering a 70 mA H{sup -}-beam in 1.45 ms pulses at a repetition rate of 50 Hz are necessary. A low emittance is another important prerequisite. The source must operate, while meeting the performance requirements, with a constancy and reliability over an acceptable period of time. The present paper summarizes the progress achieved in ion sources development of intense, single charge, positive and negative ion beams. (author) 16 figs., 7 refs.

  3. High current ion source development at Frankfurt

    International Nuclear Information System (INIS)

    Volk, K.; Klein, H.; Lakatos, A.; Maaser, A.; Weber, M.

    1995-01-01

    The development of high current positive and negative ion sources is an essential issue for the next generation of high current linear accelerators. Especially, the design of the European Spallation Source facility (ESS) and the International Fusion Material Irradiation Test Facility (IFMIF) have increased the significance of high brightness hydrogen and deuterium sources. As an example, for the ESS facility, two H - -sources each delivering a 70 mA H - -beam in 1.45 ms pulses at a repetition rate of 50 Hz are necessary. A low emittance is another important prerequisite. The source must operate, while meeting the performance requirements, with a constancy and reliability over an acceptable period of time. The present paper summarizes the progress achieved in ion sources development of intense, single charge, positive and negative ion beams. (author) 16 figs., 7 refs

  4. Trust in Co-sourced Software Development

    DEFF Research Database (Denmark)

    Schlichter, Bjarne Rerup; Persson, John Stouby

    2014-01-01

    Software development projects are increasingly geographical distributed with offshoring. Co-sourcing is a highly integrative and cohesive approach, seen successful, to software development offshoring. However, research of how dynamic aspects of trust are shaped in co-sourcing activities is limite...... understanding or personal trust relations. The paper suggests how certain work practices among developers and managers can be explained using a dynamic trust lens based on Abstract Systems, especially dis- and re-embedding mechanisms......Software development projects are increasingly geographical distributed with offshoring. Co-sourcing is a highly integrative and cohesive approach, seen successful, to software development offshoring. However, research of how dynamic aspects of trust are shaped in co-sourcing activities is limited...

  5. Application for approval of derived authorized limits for the release of the 190-C trenches and 105-C process water tunnels at the Hanford Site: Volume 2 - source term development

    International Nuclear Information System (INIS)

    Denham, D.H.; Winslow, S.L.; Moeller, M.P.; Kennedy, W.E. Jr.

    1997-03-01

    As part of environmental restoration activities at the Hanford Site, Bechtel Hanford, Inc. is conducting a series of evaluations to determine appropriate release conditions for specific facilities following the completion of decontamination and decommissioning projects. The release conditions, with respect to the residual volumetric radioactive contamination, are termed authorized limits. This report presents the summary of the supporting information and the final application for approval of derived authorized limits for the release of the 190-C trenches and the 105-C process water tunnels. This document contains two volumes; this volume (Vol. 2) contains the radiological characterization data, spreadsheet analyses, and radiological source terms

  6. Open source software development : some historical perspectives

    NARCIS (Netherlands)

    Nuvolari, A.

    2005-01-01

    In this paper we suggest that historical studies of technology can help us to account for some, perplexing (at least for traditional economic reasoning) features of open source software development. From a historical perspective, open source software seems to be a particular case of what Robert C.

  7. Open source software development : some historical perspectives

    NARCIS (Netherlands)

    Nuvolari, A.

    2003-01-01

    In this paper we suggest that historical studies of technology can help us to account for some, perplexing (at least for traditional economic reasoning) features of open source software development. When looked in historical perspective, open source software seems to be a particular case of what

  8. Using Bayesian Belief Network (BBN) modelling for rapid source term prediction. Final report

    International Nuclear Information System (INIS)

    Knochenhauer, M.; Swaling, V.H.; Dedda, F.D.; Hansson, F.; Sjoekvist, S.; Sunnegaerd, K.

    2013-10-01

    The project presented in this report deals with a number of complex issues related to the development of a tool for rapid source term prediction (RASTEP), based on a plant model represented as a Bayesian belief network (BBN) and a source term module which is used for assigning relevant source terms to BBN end states. Thus, RASTEP uses a BBN to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, composition, timing, and release path of released radio-nuclides). The output is a set of possible source terms with associated probabilities. One major issue has been associated with the integration of probabilistic and deterministic analyses are addressed, dealing with the challenge of making the source term determination flexible enough to give reliable and valid output throughout the accident scenario. The potential for connecting RASTEP to a fast running source term prediction code has been explored, as well as alternative ways of improving the deterministic connections of the tool. As part of the investigation, a comparison of two deterministic severe accident analysis codes has been performed. A second important task has been to develop a general method where experts' beliefs can be included in a systematic way when defining the conditional probability tables (CPTs) in the BBN. The proposed method includes expert judgement in a systematic way when defining the CPTs of a BBN. Using this iterative method results in a reliable BBN even though expert judgements, with their associated uncertainties, have been used. It also simplifies verification and validation of the considerable amounts of quantitative data included in a BBN. (Author)

  9. Using Bayesian Belief Network (BBN) modelling for rapid source term prediction. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Knochenhauer, M.; Swaling, V.H.; Dedda, F.D.; Hansson, F.; Sjoekvist, S.; Sunnegaerd, K. [Lloyd' s Register Consulting AB, Sundbyberg (Sweden)

    2013-10-15

    The project presented in this report deals with a number of complex issues related to the development of a tool for rapid source term prediction (RASTEP), based on a plant model represented as a Bayesian belief network (BBN) and a source term module which is used for assigning relevant source terms to BBN end states. Thus, RASTEP uses a BBN to model severe accident progression in a nuclear power plant in combination with pre-calculated source terms (i.e., amount, composition, timing, and release path of released radio-nuclides). The output is a set of possible source terms with associated probabilities. One major issue has been associated with the integration of probabilistic and deterministic analyses are addressed, dealing with the challenge of making the source term determination flexible enough to give reliable and valid output throughout the accident scenario. The potential for connecting RASTEP to a fast running source term prediction code has been explored, as well as alternative ways of improving the deterministic connections of the tool. As part of the investigation, a comparison of two deterministic severe accident analysis codes has been performed. A second important task has been to develop a general method where experts' beliefs can be included in a systematic way when defining the conditional probability tables (CPTs) in the BBN. The proposed method includes expert judgement in a systematic way when defining the CPTs of a BBN. Using this iterative method results in a reliable BBN even though expert judgements, with their associated uncertainties, have been used. It also simplifies verification and validation of the considerable amounts of quantitative data included in a BBN. (Author)

  10. Centrifugal Filtration System for Severe Accident Source Term Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shu Chang; Yim, Man Sung [KAIST, Daejeon (Korea, Republic of)

    2016-05-15

    The objective of this paper is to present the conceptual design of a filtration system that can be used to process airborne severe accident source term. Reactor containment may lose its structural integrity due to over-pressurization during a severe accident. This can lead to uncontrolled radioactive releases to the environment. For preventing the dispersion of these uncontrolled radioactive releases to the environment, several ways to capture or mitigate these radioactive source term releases are under investigation at KAIST. Such technologies are based on concepts like a vortex-like air curtain, a chemical spray, and a suction arm. Treatment of the radioactive material captured by these systems would be required, before releasing to environment. For current filtration systems in the nuclear industry, IAEA lists sand, multi-venturi scrubber, high efficiency particulate arresting (HEPA), charcoal and combinations of the above in NS-G-1-10, 4.143. Most if not all of the requirements of the scenario for applying this technology near the containment of an NPP site and the environmental constraints were analyzed for use in the design of the centrifuge filtration system.

  11. Atucha-I source terms for sequences initiated by transients

    International Nuclear Information System (INIS)

    Baron, J.; Bastianelli, B.

    1997-01-01

    The present work is part of an expected source terms study in the Atucha I nuclear power plant during severe accidents. From the accident sequences with a significant probability to produce core damage, those initiated by operational transients have been identified as the most relevant. These sequences have some common characteristics, in the sense that all of them resume in the opening of the primary system safety valves, and leave this path open for the coolant loss. In the case these sequences continue as severe accidents, the same path will be used for the release of the radionuclides, from the core, through the primary system and to the containment. Later in the severe accident sequence, the failure of the pressure vessel will occur, and the corium will fall inside the reactor cavity, interacting with the concrete. During these processes, more radioactive products will be released inside the containment. In the present work the severe accident simulation initiated by a blackout is performed, from the point of view of the phenomenology of the behavior of the radioactive products, as they are transported in the piping, during the core-concrete interactions, and inside the containment buildings until it failure. The final result is the source term into the atmosphere. (author) [es

  12. NRC source term assessment for incident response dose projections

    International Nuclear Information System (INIS)

    Easley, P.; Pasedag, W.

    1984-01-01

    The NRC provides advice and assistance to licensees and State and local authorities in responding to accidents. The TACT code supports this function by providing source term projections for two situations during early (15 to 60 minutes) accident response: (1) Core/containment damage is indicated, but there are no measured releases. Quantification of a predicted release permits emergency response before people are exposed. With TACT, response personnel can estimate releases based on fuel and cladding conditions, coolant boundary and containment integrity, and mitigative systems operability. For this type of estimate, TACT is intermediate between default assumptions and time-consuming mechanistic codes. (2) A combination of plant status and limited release data are available. For this situation, iterations between predictions based on known conditions which are compared to measured releases gives reasonable confidence in supplemental source term information otherwise unavailable: nuclide mix, releases not monitored, and trending or abrupt changes. The assumptions and models used in TACT, and examples of its use, are given in this paper

  13. Chernobyl source term, atmospheric dispersion, and dose estimation

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Harvey, T.F.; Lange, R.

    1988-02-01

    The Chernobyl source term available for long-range transport was estimated by integration of radiological measurements with atmospheric dispersion modeling, and by reactor core radionuclide inventory estimation in conjunction with WASH-1400 release fractions associated with specific chemical groups. These analyses indicated that essentially all of the noble gases, 80% of the radioiodines, 40% of the radiocesium, 10% of the tellurium, and about 1% or less of the more refractory elements were released. Atmospheric dispersion modeling of the radioactive cloud over the Northern Hemisphere revealed that the cloud became segmented during the first day, with the lower section heading toward Scandinavia and the uppper part heading in a southeasterly direction with subsequent transport across Asia to Japan, the North Pacific, and the west coast of North America. The inhalation doses due to direct cloud exposure were estimated to exceed 10 mGy near the Chernobyl area, to range between 0.1 and 0.001 mGy within most of Europe, and to be generally less than 0.00001 mGy within the US. The Chernobyl source term was several orders of magnitude greater than those associated with the Windscale and TMI reactor accidents, while the 137 Cs from the Chernobyl event is about 6% of that released by the US and USSR atmospheric nuclear weapon tests. 9 refs., 3 figs., 6 tabs

  14. Analysis of the source term in the Chernobyl-4 accident

    International Nuclear Information System (INIS)

    Alonso, A.; Lopez Montero, J.V.; Pinedo Garrido, P.

    1990-01-01

    The report presents the analysis of the Chernobyl accident and of the phenomena with major influence on the source term, including the chemical effects of materials dumped over the reactor, carried out by the Chair of Nuclear Technology at Madrid University under a contract with the CEC. It also includes the comparison of the ratio (Cs-137/Cs-134) between measurements performed by Soviet authorities and countries belonging to the Community and OECD area. Chapter II contains a summary of both isotope measurements (Cs-134 and Cs-137), and their ratios, in samples of air, water, soil and agricultural and animal products collected by the Soviets in their report presented in Vienna (1986). Chapter III reports on the inventories of cesium isotopes in the core, while Chapter IV analyses the transient, especially the fuel temperature reached, as a way to deduce the mechanisms which took place in the cesium escape. The cesium source term is analyzed in Chapter V. Normal conditions have been considered, as well as the transient and the post-accidental period, including the effects of deposited materials. The conclusion of this study is that Chernobyl accidental sequence is specific of the RBMK type of reactors, and that in the Western world, basic research on fuel behaviour for reactivity transients has already been carried out

  15. Conditioning of disused sealed sources in countries without disposal facility: Short term gain - long term pain

    International Nuclear Information System (INIS)

    Benitez-Navarro, J.C.; Salgado-Mojena, M.

    2002-01-01

    Owing to the considerable development in managing disused sealed radioactive sources (DSRS), the limited availability of disposal practices for them, and the new recommendations for the use of borehole disposal concept, it was felt that a paper reviewing the existing recommendations could be a starting point of discussion on the retrievability of the sources. Even when no international consensus exists as to an acceptable solution for the challenge of disposal of disused sealed sources, the 'Best Available Technology' for managing most of them, recommended for developing countries, included the cementation of the sources. The waste packages prepared in such a way do not allow any flexibility to accommodate possible future disposal requirements. Therefore, the 'Wait and See' approach could be also recommended for managing not only the sources with long-live radionuclides and high activity, but probably for all kind of existing disused sealed sources. The general aim of the current paper is to identify and review the current recommendations for managing disused sealed sources and to meditate on the most convenient management schemes for disused sealed radioactive sources in Member States without disposal capacities (Latin America, Africa). The risk that cemented DSRS could be incompatible with future disposal requirements was taken into account. (author)

  16. Co-sourcing in software development offshoring

    DEFF Research Database (Denmark)

    Schlichter, Bjarne Rerup; Persson, John Stouby

    2013-01-01

    Software development projects are increasingly geographical distributed with offshoring, which introduce complex risks that can lead to project failure. Co-sourcing is a highly integrative and cohesive approach, seen successful, to software development offshoring. However, research of how co......-sourcing shapes the perception and alleviation of common offshoring risks is limited. We present a case study of how a certified CMMI-level 5 Danish software supplier approaches these risks in offshore co-sourcing. The paper explains how common offshoring risks are perceived and alleviated when adopting the co...

  17. Synchrotron light sources in developing countries

    Science.gov (United States)

    Mtingwa, Sekazi K.; Winick, Herman

    2018-03-01

    We discuss the role that synchrotron light sources, such as SESAME, could play in improving the socioeconomic conditions in developing countries. After providing a brief description of a synchrotron light source, we discuss the important role that they played in the development of several economically emerging countries. Then we describe the state of synchrotron science in South Africa and that country’s leadership role in founding the African Light Source initiative. Next, we highlight a new initiative called Lightsources for Africa, the Americas & Middle East Project, which is a global initiative led by the International Union of Pure and Applied Physics and the International Union of Crystallography, with initial funding provided by the International Council for Science. Finally, we comment on a new technology called the multibend achromat that has launched a new paradigm for the design of synchrotron light sources that should be attractive for construction in developing countries.

  18. Use of source term uncoupled in radionuclide migration equations

    International Nuclear Information System (INIS)

    Silveira, Claudia Siqueira da; Lima, Zelmo Rodrigues de; Alvim, Antonio Carlos Marques

    2008-01-01

    Final repositories of high-level radioactive waste have been considered in deep, low permeability and stable geological formations. A common problem found is the migration modeling of radionuclides in a fractured rock. In this work, the physical system adopted consists of the rock matrix containing a single planar fracture situated in water saturated porous rock. The partial differential equations that describe the radionuclide transport were discretized using finite differences techniques, of which the following methods were adopted: Explicit Euler, Implicit Euler and Crank-Nicholson. For each one of these methods, the advective term was discretized with the following numerical schemes: backward differences, centered differences and forward differences. We make a comparison to determine which temporal and space discretization has the best result in relation to a reference solution. The obtained results show that the Explicit Euler Method with forward discretization in the advective term has a good accuracy. Next, with the objective of improving the answer of the Implicit Euler and Crank-Nicholson Methods it was accomplished a source term uncouplement, the diffusive flux. The obtained results were considered satisfactory by comparison with previous studies. (author)

  19. Preliminary investigation of processes that affect source term identification

    International Nuclear Information System (INIS)

    Wickliff, D.S.; Solomon, D.K.; Farrow, N.D.

    1991-09-01

    Solid Waste Storage Area (SWSA) 5 is known to be a significant source of contaminants, especially tritium ( 3 H), to the White Oak Creek (WOC) watershed. For example, Solomon et al. (1991) estimated the total 3 H discharge in Melton Branch (most of which originates in SWSA 5) for the 1988 water year to be 1210 Ci. A critical issue for making decisions concerning remedial actions at SWSA 5 is knowing whether the annual contaminant discharge is increasing or decreasing. Because (1) the magnitude of the annual contaminant discharge is highly correlated to the amount of annual precipitation (Solomon et al., 1991) and (2) a significant lag may exist between the time of peak contaminant release from primary sources (i.e., waste trenches) and the time of peak discharge into streams, short-term stream monitoring by itself is not sufficient for predicting future contaminant discharges. In this study we use 3 H to examine the link between contaminant release from primary waste sources and contaminant discharge into streams. By understanding and quantifying subsurface transport processes, realistic predictions of future contaminant discharge, along with an evaluation of the effectiveness of remedial action alternatives, will be possible. The objectives of this study are (1) to characterize the subsurface movement of contaminants (primarily 3 H) with an emphasis on the effects of matrix diffusion; (2) to determine the relative strength of primary vs secondary sources; and (3) to establish a methodology capable of determining whether the 3 H discharge from SWSA 5 to streams is increasing or decreasing

  20. Developer Network : Open Source Personal Digital Assistant ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Each project used a different software, however, and this proved costly in terms of ... development and evaluation of PDACT, a Palm TM pilot interviewing system ... IWRA/IDRC webinar on climate change and adaptive water management.

  1. Electron Storage Ring Development for ICS Sources

    Energy Technology Data Exchange (ETDEWEB)

    Loewen, Roderick [Lyncean Technologies, Inc., Palo Alto, CA (United States)

    2015-09-30

    There is an increasing world-wide interest in compact light sources based on Inverse Compton Scattering. Development of these types of light sources includes leveraging the investment in accelerator technology first developed at DOE National Laboratories. Although these types of light sources cannot replace the larger user-supported synchrotron facilities, they offer attractive alternatives for many x-ray science applications. Fundamental research at the SLAC National Laboratory in the 1990’s led to the idea of using laser-electron storage rings as a mechanism to generate x-rays with many properties of the larger synchrotron light facilities. This research led to a commercial spin-off of this technology. The SBIR project goal is to understand and improve the performance of the electron storage ring system of the commercially available Compact Light Source. The knowledge gained from studying a low-energy electron storage ring may also benefit other Inverse Compton Scattering (ICS) source development. Better electron storage ring performance is one of the key technologies necessary to extend the utility and breadth of applications of the CLS or related ICS sources. This grant includes a subcontract with SLAC for technical personnel and resources for modeling, feedback development, and related accelerator physics studies.

  2. Development of nuclear battery using isotope sources

    International Nuclear Information System (INIS)

    Chang, Won Jun

    2004-02-01

    Until now, the development of the useful micro electromechanical systems has the problems because previous batteries (solar, chemical, etc) did not satisfy the requirements related to power supply. At this point of time, nuclear battery using isotope sources is rising the solution of this problem. Nuclear battery can provide superior out-put power and lifetime. So a new type of micro power source (nuclear battery) for micro electromechanical systems has been designed and analyzed. In this work, I designed the three parts, isotope source, conversion device, and shielding. I chose suitable sources, and designed semiconductor using the chosen isotope sources. Power is generated by radiation exciting electrons in the semiconductor depletion region. The efficiency of the nuclear battery depends upon the pn-junction. In this study the several conceptual nuclear batteries using radioactive materials are described with pn-junction. And for the safety, I designed the shielding to protect the environment by reducing the kinetic energy of beta particles

  3. A comparison of world-wide uses of severe reactor accident source terms

    International Nuclear Information System (INIS)

    Ang, M.L.; Frid, W.; Kersting, E.J.; Friederichs, H.G.; Lee, R.Y.; Meyer-Heine, A.; Powers, D.A.; Soda, K.; Sweet, D.

    1994-09-01

    The definitions of source terms to reactor containments and source terms to the environment are discussed. A comparison is made between the TID-14844 example source term and the alternative source term described in NUREG-1465. Comparisons of these source terms to the containments and those used in France, Germany, Japan, Sweden, and the United Kingdom are made. Source terms to the environment calculated in NUREG-1500 and WASH-1400 are discussed. Again, these source terms are compared to those now being used in France, Germany, Japan, Sweden, and the United Kingdom. It is concluded that source terms to the containment suggested in NUREG-1465 are not greatly more conservative than those used in other countries. Technical bases for the source terms are similar. The regulatory use of the current understanding of radionuclide behavior varies among countries

  4. Intrinsic Motivation in Open Source Software Development

    DEFF Research Database (Denmark)

    Bitzer, J.; W., Schrettl,; Schröder, Philipp

    2004-01-01

    This papers sheds light on the puzzling evidence that even though open source software (OSS) is a public good, it is developed for free by highly qualified, young and motivated individuals, and evolves at a rapid pace. We show that once OSS development is understood as the private provision...

  5. Influence of iodine chemistry on source term assessment

    International Nuclear Information System (INIS)

    Herranz Puebla, L. E.; Lopez Diez, I.; Rodriguez Maroto, J. J.; Martinez Lopez-Alcorocho, A.

    1991-01-01

    The major goal of a phenomenology analysis of containment during a severe accident situation can be spitted into the following ones: to know the containment response to the different loads and to predict accurately the fission product and aerosol behavior. In this report, the main results coming from the study of a hypothetical accident scenario, based on LA-4 experiment of LACE project, are presented. In order to do it, several codes have been coupled: CONTEMPT4/MOD5 (thermohydraulics), NAUA/MOD5 (aerosol physics) and IODE (iodine chemistry). It has been demonstrated the impossibility of assessing with confidence the Source Term if the chemical conduct of some radionuclides is not taken into account. In particular, the influence on the iodine retention efficiency of the sump of variables such as pH has been proven. (Author)12 refs

  6. Tank waste source term inventory validation. Volume II. Letter report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This document comprises Volume II of the Letter Report entitled Tank Waste Source Term Inventory Validation. This volume contains Appendix C, Radionuclide Tables, and Appendix D, Chemical Analyte Tables. The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories.

  7. Tank waste source term inventory validation. Volume 1. Letter report

    International Nuclear Information System (INIS)

    Brevick, C.H.; Gaddis, L.A.; Johnson, E.D.

    1995-01-01

    The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories. This document is Volume I of the Letter Report entitled Tank Waste Source Term Inventory Validation

  8. Running the source term code package in Elebra MX-850

    International Nuclear Information System (INIS)

    Guimaraes, A.C.F.; Goes, A.G.A.

    1988-01-01

    The source term package (STCP) is one of the main tools applied in calculations of behavior of fission products from nuclear power plants. It is a set of computer codes to assist the calculations of the radioactive materials leaving from the metallic containment of power reactors to the environment during a severe reactor accident. The original version of STCP runs in SDC computer systems, but as it has been written in FORTRAN 77, is possible run it in others systems such as IBM, Burroughs, Elebra, etc. The Elebra MX-8500 version of STCP contains 5 codes:March 3, Trapmelt, Tcca, Vanessa and Nava. The example presented in this report has taken into consideration a small LOCA accident into a PWR type reactor. (M.I.)

  9. Tank waste source term inventory validation. Volume II. Letter report

    International Nuclear Information System (INIS)

    1995-04-01

    This document comprises Volume II of the Letter Report entitled Tank Waste Source Term Inventory Validation. This volume contains Appendix C, Radionuclide Tables, and Appendix D, Chemical Analyte Tables. The sample data for selection of 11 radionuclides and 24 chemical analytes were extracted from six separate sample data sets, were arranged in a tabular format and were plotted on scatter plots for all of the 149 single-shell tanks, the 24 double-shell tanks and the four aging waste tanks. The solid and liquid sample data was placed in separate tables and plots. The sample data and plots were compiled from the following data sets: characterization raw sample data, recent core samples, D. Braun data base, Wastren (Van Vleet) data base, TRAC and HTCE inventories

  10. The Phebus Fission Product and Source Term International Programmes

    International Nuclear Information System (INIS)

    Clement, B.; Zeyen, R.

    2005-01-01

    The international Phebus FP programme, initiated in 1988 is one of the major research programmes on light water reactors severe accidents. After a short description of the facility and of the test matrix, the main outcomes and results of the first four integral tests are provided and analysed. Several results were unexpected and some are of importance for safety analyses, particularly concerning fuel degradation, cladding oxidation, chemical form of some fission products, especially iodine, effect of control rod materials on degradation and chemistry, iodine behaviour in the containment. Prediction capabilities of calculation tools have largely been improved as a result of this research effort. However, significant uncertainties remain for a number of phenomena, requiring detailed physical analysis and implementation of improved models in codes, sustained by a number of separate-effect experiments. This is the subject of the new Source Term programme for a better understanding of the phenomenology on important safety issues, in accordance with priorities defined in the EURSAFE project of the 5 th European framework programme aiming at reducing the uncertainties on Source Term analyses. It covers iodine chemistry, impact of boron carbide control rods degradation and oxidation, air ingress situations and fission product release from fuel. Regarding the interpretation of Phebus, an international co-operation has been established since over ten years, particularly helpful for the improvement and common understanding of severe accident phenomena. Few months ago, the Phebus community was happy to welcome representatives of a large number of organisations from the following new European countries: the Czech republic, Hungary, Lithuania, Slovakia, Slovenia and also from Bulgaria and Romania. (author)

  11. Recent negative ion source developments at ORNL

    International Nuclear Information System (INIS)

    Alton, G.D.

    1979-01-01

    According to specifications written for the 25 MV ORNL tandem accelerator, the ion source used during acceptance testing must be capable of producing a negative ion beam of intensity greater than or equal to 7.5 μA within a phase space of less than or equal to 1 π cm-mrad (MeV)/sup 1/2/. The specifications were written prior to the development of an ion source with such capabilities but fortunately Andersen and Tykesson introduced a source in 1975 which could easily meet the specified requirements. The remarkable beam intensity and quality properties of this source has motivated the development of other sources which utilize sputtering in the presence of a diffuse cesium plasma - some of which will be described in these proceedings. This report describes results of studies associated with the development of a modified Aarhus geometry and an axial geometry source which utilize sputtering in the presence of a diffuse cesium plasma for the production of negative ion beams

  12. Review of the accident source terms for aluminide fuel: Application to the BR2 reactor

    International Nuclear Information System (INIS)

    Joppen, F.

    2005-01-01

    A major safety review of the BR2, a material test reactor, is to be conducted for the year 2006. One of the subjects selected for the safety review is the definition of source terms for emergency planning and in particular the development of accident scenarios. For nuclear power plants the behaviour of fuel under accident conditions is a well studied object. In case of non-power reactors this basic knowledge is rather scarce. The usefulness of information from power plant fuels is limited due to the differences in fuel type, power level and thermohydraulical conditions. First investigation indicates that using data from power plant fuel leads to an overestimation of the source terms. Further research on this subject could be very useful for the research reactor community, in order to define more realistic source terms and to improve the emergency preparedness. (author)

  13. Recent UCN source developments at Los Alamos

    International Nuclear Information System (INIS)

    Seestrom, S.J.; Anaya, J.M.; Bowles, T.J.

    1998-01-01

    The most intense sources of ultra cold neutrons (UCN) have bee built at reactors where the high average thermal neutron flux can overcome the low UCN production rate to achieve usable densities of UCN. At spallation neutron sources the average flux available is much lower than at a reactor, though the peak flux can be comparable or higher. The authors have built a UCN source that attempts to take advantage of the high peak flux available at the short pulse spallation neutron source at the Los Alamos Neutron Science Center (LANSCE) to generate a useful number of UCN. In the source UCN are produced by Doppler-shifted Bragg scattering of neutrons to convert 400-m/s neutrons down into the UCN regime. This source was initially tested in 1996 and various improvements were made based on the results of the 1996 running. These improvements were implemented and tested in 1997. In sections 2 and 3 they discuss the improvements that have been made and the resulting source performance. Recently an even more interesting concept was put forward by Serebrov et al. This involves combining a solid Deuterium UCN source, previously studied by Serebrov et al., with a pulsed spallation source to achieve world record UCN densities. They have initiated a program of calculations and measurements aimed at verifying the solid Deuterium UCN source concept. The approach has been to develop an analytical capability, combine with Monte Carlo calculations of neutron production, and perform benchmark experiments to verify the validity of the calculations. Based on the calculations and measurements they plan to test a modified version of the Serebrov UCN factory. They estimate that they could produce over 1,000 UCN/cc in a 15 liter volume, using 1 microamp of 800 MeV protons for two seconds every 500 seconds. They will discuss the result UCN production measurements in section 4

  14. Long term planning for wind energy development

    International Nuclear Information System (INIS)

    Trinick, M.

    1995-01-01

    In a planning system intended to be governed primarily by policies in statutory plans a reasonable horizon for long term planning is 10 years or longer. Because of statutory requirements, developers have no option but to pay due regard to, and take a full part in, long term planning. The paper examines the type of policies which have emerged in the last few years to cater for wind energy development. It canvasses the merits of different types of policies. Finally, it discusses the policy framework which may emerge to cater for development outside NFFO. (Author)

  15. Terms of trade and Russian economic development

    Directory of Open Access Journals (Sweden)

    Georgy Idrisov

    2016-09-01

    Full Text Available The paper discusses economic development trends in Russia in late 2014 and 2015 and reviews the basic mechanisms of how changes in the terms of trade affect the economic development of countries from a historical perspective and with a particular focus on those changes in the Russian economy that occurred in late 2014 and 2015. The authors demonstrate that structural reforms aimed at diversification of production and exports are necessary for sustainable economic development, for social stability and for reducing the impact of variability in the terms of trade on the Russian economy. During periods of instability in the government agenda's measures for the real and financial sectors, it is necessary not only to compensate economic agents losses caused by changes in the terms of trade but also to improve the economic structure and to develop and enhance the stability of the financial markets.

  16. The History of Cartographic Sources Development

    Directory of Open Access Journals (Sweden)

    L. Volkotrub

    2016-07-01

    Full Text Available Cartographic sources are the variety of descriptive sources. They include historical and geographical maps and circuits maps. The image maps are a special kind of modeling the real phenomenon, that broadcasts their quantitative and qualitative characteristics, structure, interconnections and dynamic in a graphic form. The prototypes of maps appeared as a way of transmitting information around the world. People began to use this way of communication long before the appearance of writing. The quality of mapping images matched with the evolution of techniques and methods of mapping and publishing. The general development of cartographic sources is determined primarily by three factors: the development of science and technology, the needs of society in different cartographic works, political and economic situation of country. Given this, map is an all-sufficient phenomenon, its sources expert study is based on understanding of invariance of its perception. Modern theoretical concepts show us the invariance of maps. Specifially, map is viewed in the following aspects: 1 it is one of the universal models of land and existing natural and social processes.2 it is one of the tools of researching and forecasting. 3 it is a specific language formation. 4 it is a method of transferring information. As a source map may contain important information about physical geography, geology, hydrology, political-administrative division, population, flora and fauna of a particular area in a particular period. Mostly, cartographic sources are complex, because they contain a lot of cognitive and historical information.

  17. Development of a circadian light source

    Science.gov (United States)

    Nicol, David B.; Ferguson, Ian T.

    2002-11-01

    Solid state lighting presents a new paradigm for lighting - controllability. Certain characteristics of the lighting environment can be manipulated, because of the possibility of using multiple LEDs of different emission wavelengths as the illumination source. This will provide a new, versatile, general illumination source due to the ability to vary the spectral power distribution. New effects beyond the visual may be achieved that are not possible with conventional light sources. Illumination has long been the primary function of lighting but as the lighting industry has matured the psychological aspects of lighting have been considered by designers; for example, choosing a particular lighting distribution or color variation in retail applications. The next step in the evolution of light is to consider the physiological effects of lighting that cause biological changes in a person within the environment. This work presents the development of a source that may have important bearing on this area of lighting. A circadian light source has been developed to provide an illumination source that works by modulating its correlated color temperature to mimic the changes in natural daylight through the day. In addition, this source can cause or control physiological effects for a person illuminated by it. The importance of this is seen in the human circadian rhythm's peak response corresponding to blue light at ~460 nm which corresponds to the primary spectral difference in increasing color temperature. The device works by adding blue light to a broadband source or mixing polychromatic light to mimic the variation of color temperature observed for the Planckian Locus on the CIE diagram. This device can have several applications including: a tool for researchers in this area, a general illumination lighting technology, and a light therapy device.

  18. The source development lab linac at BNL

    International Nuclear Information System (INIS)

    Graves, W.S.; Johnson, E.D.

    1996-12-01

    A 210 MeV SLAC-type electron linac is currently under construction at BNL as part of the Source Development Laboratory. A 1.6 cell RF photoinjector is employed as the high brightness electron source which is excited by a frequency tripled Titanium:Sapphire laser. This linac will be used for several source development projects including a short bunch storage ring, and a series of FEL experiments based on the 10 m long NISUS undulator. The FEL will be operated as either a SASE or seeded beam device using the Ti:Sapp laser. For the seeded beam experiments; direct amplification, harmonic generation, and chirped pulse amplification modes will be studied, spanning an output wavelength range from 900 nm down to 100 nm. This paper presents the project's design parameters and results of recent modeling using the PARMELA and MAD simulation codes

  19. Communal Resources in Open Source Software Development

    Science.gov (United States)

    Spaeth, Sebastian; Haefliger, Stefan; von Krogh, Georg; Renzl, Birgit

    2008-01-01

    Introduction: Virtual communities play an important role in innovation. The paper focuses on the particular form of collective action in virtual communities underlying as Open Source software development projects. Method: Building on resource mobilization theory and private-collective innovation, we propose a theory of collective action in…

  20. A simplified approach to evaluating severe accident source term for PWR

    International Nuclear Information System (INIS)

    Huang, Gaofeng; Tong, Lili; Cao, Xuewu

    2014-01-01

    Highlights: • Traditional source term evaluation approaches have been studied. • A simplified approach of source term evaluation for 600 MW PWR is studied. • Five release categories are established. - Abstract: For early design of NPPs, no specific severe accident source term evaluation was considered. Some general source terms have been used for some NPPs. In order to implement a best estimate, a special source term evaluation should be implemented for an NPP. Traditional source term evaluation approaches (mechanism approach and parametric approach) have some difficulties associated with their implementation. The traditional approaches are not consistent with cost-benefit assessment. A simplified approach for evaluating severe accident source term for PWR is studied. For the simplified approach, a simplified containment event tree is established. According to representative cases selection, weighted coefficient evaluation, computation of representative source term cases and weighted computation, five containment release categories are established, including containment bypass, containment isolation failure, containment early failure, containment late failure and intact containment

  1. Evaluation Plan on In-vessel Source Term in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Won; Ha, Kwi-Seok; Ahn, Sang June; Lee, Kwi Lim; Jeong, Taekyeong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    This strategy requires nuclear plants to have features that prevent radionuclide release and multiple barriers to the escape from the plants of any radionuclides that are released despite preventive measures. Considerations of the ability to prevent and mitigate release of radionuclides arise at numerous places in the safety regulations of nuclear plants. The effectiveness of mitigative capabilities in nuclear plants is subject to quantitative analysis. The radionuclide input to these quantitative analyses of effectiveness is the Source Term (ST). All features of the composition, magnitude, timing, chemical form and physical form of accidental radionuclide release constitute the ST. Also, ST is defined as the release of radionuclides from the fuel and coolant into the containment, and subsequently to the environment. The in-vessel STs of PGSFR will be estimated using the methodology of ANL-ART-38 report in additional to 4S methodology. The in-vessel STs are calculated through several phases: The inventory of each radionuclide is calculated by ORIGEN-2 code using the realistic burnup conditions. ST in the release from the core to primary sodium is calculated by using the assumption of ANL methodology. Lastly, ST in the release from the primary sodium to cover gas space is calculated by using equation and experimental materials.

  2. Source term calculations - Ringhals 2 PWR. Interim report

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Lise-Lotte

    1998-03-01

    This project was performed within the fifth and final phase of sub-project RAK-2.1 of the Nordic Co-operative Reactor Safety Program, NKS. RAK-2.1 has also included studies of reflooding of degraded core, recriticality and late phase melt progression. Earlier source term calculations for Swedish nuclear power plants are based on the integral code MAAP. A need was recognised to compare these calculations with calculations done with mechanistic codes. In the present work SCDAP/RELAP5 and CONTAIN were used. Only limited results could be obtained within the frame of RAK-2.1, since many problems were encountered using the SCDAP/RELAP5 code. The main obstacle was the extremely long execution times of the MOD3.1 version, but also some dubious fission product calculations. However, some interesting results were obtained for the studied sequence, a total loss of AC power. The report describes the modelling approach for SCDAP/RELAP5 and CONTAIN, and discusses results for the transient including the event of a surge line creep rupture. The study will probably be completed later, providing that an improved SCDAP/RELAP5 code version becomes available 8 refs, 16 figs, 5 tabs

  3. Source term experiments project (STEP): aerosol characterization system

    International Nuclear Information System (INIS)

    Schlenger, B.J.; Dunn, P.F.

    1985-01-01

    A series of four experiments has been conducted at Argonne National Laboratory's TREAT Reactor. These experiments, which are sponsored by an international consortium organized by the Electric Power Research Institute, are designed to investigate the source term, i.e., the type, quantity and timing of release of radioactive fission products from a light water reactor to the environment in the event of a severe accident in which the core is insufficiently cooled. The STEP tests have been designed to provide some of the necessary data regarding the magnitude and release rates of volatile fission products from degraded fuel pins, their physical and chemical characteristics, and aerosol formation and transport phenomena of those fission products that condense to form particles in the cooler regions of the reactor beyond the core. These are inpile experiments, whereby the test fuels are heated in a nuclear test reactor by neutron induced fission and subsequent cladding oxidation in steam environments that simulate as closely as practical predicted severe reactor accident conditions. The test sequences cover a range of pressure and fuel heatup rate, and include the effect of Ag/In/Cd control rod material. 1 ref., 8 figs., 1 tab

  4. Verification test calculations for the Source Term Code Package

    International Nuclear Information System (INIS)

    Denning, R.S.; Wooton, R.O.; Alexander, C.A.; Curtis, L.A.; Cybulskis, P.; Gieseke, J.A.; Jordan, H.; Lee, K.W.; Nicolosi, S.L.

    1986-07-01

    The purpose of this report is to demonstrate the reasonableness of the Source Term Code Package (STCP) results. Hand calculations have been performed spanning a wide variety of phenomena within the context of a single accident sequence, a loss of all ac power with late containment failure, in the Peach Bottom (BWR) plant, and compared with STCP results. The report identifies some of the limitations of the hand calculation effort. The processes involved in a core meltdown accident are complex and coupled. Hand calculations by their nature must deal with gross simplifications of these processes. Their greatest strength is as an indicator that a computer code contains an error, for example that it doesn't satisfy basic conservation laws, rather than in showing the analysis accurately represents reality. Hand calculations are an important element of verification but they do not satisfy the need for code validation. The code validation program for the STCP is a separate effort. In general the hand calculation results show that models used in the STCP codes (e.g., MARCH, TRAP-MELT, VANESA) obey basic conservation laws and produce reasonable results. The degree of agreement and significance of the comparisons differ among the models evaluated. 20 figs., 26 tabs

  5. Evaluation Plan on In-vessel Source Term in PGSFR

    International Nuclear Information System (INIS)

    Lee, Seung Won; Ha, Kwi-Seok; Ahn, Sang June; Lee, Kwi Lim; Jeong, Taekyeong

    2016-01-01

    This strategy requires nuclear plants to have features that prevent radionuclide release and multiple barriers to the escape from the plants of any radionuclides that are released despite preventive measures. Considerations of the ability to prevent and mitigate release of radionuclides arise at numerous places in the safety regulations of nuclear plants. The effectiveness of mitigative capabilities in nuclear plants is subject to quantitative analysis. The radionuclide input to these quantitative analyses of effectiveness is the Source Term (ST). All features of the composition, magnitude, timing, chemical form and physical form of accidental radionuclide release constitute the ST. Also, ST is defined as the release of radionuclides from the fuel and coolant into the containment, and subsequently to the environment. The in-vessel STs of PGSFR will be estimated using the methodology of ANL-ART-38 report in additional to 4S methodology. The in-vessel STs are calculated through several phases: The inventory of each radionuclide is calculated by ORIGEN-2 code using the realistic burnup conditions. ST in the release from the core to primary sodium is calculated by using the assumption of ANL methodology. Lastly, ST in the release from the primary sodium to cover gas space is calculated by using equation and experimental materials

  6. Alkali deuteride negative ion source development plan

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    A three phase program is described for the development of neutral beam systems. In the first phase, concluded in May, 1977, the laser initiated source was characterized. In phase two, scheduled for completion in September, 1978, negative ion confinement and extraction are investigated using laser energy deposition as a baseline method to produce D - . In addition other energy deposition schemes are studied in order to define a baseline energetic beam source system. The third phase is devoted to producing an integrated baseline system and scaling it up in current and energy to meet magnetic confinement system requirements

  7. Developing an Inhouse Database from Online Sources.

    Science.gov (United States)

    Smith-Cohen, Deborah

    1993-01-01

    Describes the development of an in-house bibliographic database by the U.S. Army Corp of Engineers Cold Regions Research and Engineering Laboratory on arctic wetlands research. Topics discussed include planning; identifying relevant search terms and commercial online databases; downloading citations; criteria for software selection; management…

  8. Economical comparison of imported energy sources in terms of long-term production planning

    International Nuclear Information System (INIS)

    Gungor, Z.

    1999-01-01

    In this paper, the Turkish energy production sector is studied and power plants fueled by natural gas, imported coal and nuclear power are compared in terms of long-term (1996-2010) production economy. A net present value is used for comparing nuclear, coal and natural gas power plants. A scenario approach is utilized in establishing the effects of different factors, such as inflation rate, unit of investment costs, load factor change, discount rate and fuel price changes. Six different scenarios of interest are developed and discussed. The study ends with conclusions and recommendations based on a study of a reference scenario and alternative scenarios. (author)

  9. Algorithms and analytical solutions for rapidly approximating long-term dispersion from line and area sources

    Science.gov (United States)

    Barrett, Steven R. H.; Britter, Rex E.

    Predicting long-term mean pollutant concentrations in the vicinity of airports, roads and other industrial sources are frequently of concern in regulatory and public health contexts. Many emissions are represented geometrically as ground-level line or area sources. Well developed modelling tools such as AERMOD and ADMS are able to model dispersion from finite (i.e. non-point) sources with considerable accuracy, drawing upon an up-to-date understanding of boundary layer behaviour. Due to mathematical difficulties associated with line and area sources, computationally expensive numerical integration schemes have been developed. For example, some models decompose area sources into a large number of line sources orthogonal to the mean wind direction, for which an analytical (Gaussian) solution exists. Models also employ a time-series approach, which involves computing mean pollutant concentrations for every hour over one or more years of meteorological data. This can give rise to computer runtimes of several days for assessment of a site. While this may be acceptable for assessment of a single industrial complex, airport, etc., this level of computational cost precludes national or international policy assessments at the level of detail available with dispersion modelling. In this paper, we extend previous work [S.R.H. Barrett, R.E. Britter, 2008. Development of algorithms and approximations for rapid operational air quality modelling. Atmospheric Environment 42 (2008) 8105-8111] to line and area sources. We introduce approximations which allow for the development of new analytical solutions for long-term mean dispersion from line and area sources, based on hypergeometric functions. We describe how these solutions can be parameterized from a single point source run from an existing advanced dispersion model, thereby accounting for all processes modelled in the more costly algorithms. The parameterization method combined with the analytical solutions for long-term mean

  10. Added Value of uncertainty Estimates of SOurce term and Meteorology (AVESOME)

    DEFF Research Database (Denmark)

    Sørensen, Jens Havskov; Schönfeldt, Fredrik; Sigg, Robert

    In the early phase of a nuclear accident, two large sources of uncertainty exist: one related to the source term and one associated with the meteorological data. Operational methods are being developed in AVESOME for quantitative estimation of uncertainties in atmospheric dispersion prediction.......g. at national meteorological services, the proposed methodology is feasible for real-time use, thereby adding value to decision support. In the recent NKS-B projects MUD, FAUNA and MESO, the implications of meteorological uncertainties for nuclear emergency preparedness and management have been studied...... uncertainty in atmospheric dispersion model forecasting stemming from both the source term and the meteorological data is examined. Ways to implement the uncertainties of forecasting in DSSs, and the impacts on real-time emergency management are described. The proposed methodology allows for efficient real...

  11. Development of multiampere negative ion sources

    International Nuclear Information System (INIS)

    Alessi, J.; Hershcovitch, A.; Prelec, K.; Sluyters, T.

    1981-01-01

    The Neutral Beam Development Group at BNL is developing H-/D- surface plasma sources as part of a high energy neutral beam injector. Uncooled Penning and magnetron sources have operated at a maximum beam current of 1 A (10 ms pulses, Mk III) and a maximum pulse length of 200 ms (0.3 A, Mk IV). A magnetron source with focusing grooves on the cathode and an asymmetric anode-cathode geometry operates at a power efficiency of 8 kW/A and a 6% gas efficiency. As the next step, a water cooled magnetron, designed to give a steady state beam of 1 to 2 A, has been constructed. Experiments are in progress to test a modification of the magnetron which may significantly improve its performance. By injecting a sheet of plasma, produced by a highly gas efficient hollow cathode discharge, into a magnetron type anode-cathode geometry, we anticipate a reduction of the source operating pressure by at least three orders of magnitude. Initial experiments have given indications of H - production. The next plasma injection experiment is designed to give a steady state beam of approx. = 1 A

  12. PLOTLIB: a computerized nuclear waste source-term library storage and retrieval system

    International Nuclear Information System (INIS)

    Marshall, J.R.; Nowicki, J.A.

    1978-01-01

    The PLOTLIB code was written to provide computer access to the Nuclear Waste Source-Term Library for those users with little previous computer programming experience. The principles of user orientation, quick accessibility, and versatility were extensively employed in the development of the PLOTLIB code to accomplish this goal. The Nuclear Waste Source-Term Library consists of 16 ORIGEN computer runs incorporating a wide variety of differing light water reactor (LWR) fuel cycles and waste streams. The typical isotopic source-term data consist of information on watts, curies, grams, etc., all of which are compiled as a function of time after reactor discharge and unitized on a per metric ton heavy metal basis. The information retrieval code, PLOTLIB, is used to process source-term information requests into computer plots and/or user-specified output tables. This report will serve both as documentation of the current data library and as an operations manual for the PLOTLIB computer code. The accompanying input description, program listing, and sample problems make this code package an easily understood tool for the various nuclear waste studies under way at the Office of Waste Isolation

  13. Development of an application simulating radioactive sources

    International Nuclear Information System (INIS)

    Riffault, V.; Locoge, N.; Leblanc, E.; Vermeulen, M.

    2011-01-01

    This paper presents an application simulating radioactive gamma sources developed in the 'Ecole des Mines' of Douai (France). It generates raw counting data as an XML file which can then be statistically exploited to illustrate the various concepts of radioactivity (exponential decay law, isotropy of the radiation, attenuation of radiation in matter). The application, with a spread sheet for data analysis and lab procedures, has been released under free license. (authors)

  14. Development of methodology for the characterization of radioactive sealed sources

    International Nuclear Information System (INIS)

    Ferreira, Robson de Jesus

    2010-01-01

    Sealed radioactive sources are widely used in many applications of nuclear technology in industry, medicine, research and others. The International Atomic Energy Agency (IAEA) estimates tens of millions sources in the world. In Brazil, the number is about 500 thousand sources, if the Americium-241 sources present in radioactive lightning rods and smoke detectors are included in the inventory. At the end of the useful life, most sources become disused, constitute a radioactive waste, and are then termed spent sealed radioactive sources (SSRS). In Brazil, this waste is collected by the research institutes of the Nuclear Commission of Nuclear Energy and kept under centralized storage, awaiting definition of the final disposal route. The Waste Management Laboratory (WML) at the Nuclear and Energy Research Institute is the main storage center, having received until July 2010 about 14.000 disused sources, not including the tens of thousands of lightning rod and smoke detector sources. A program is underway in the WML to replacing the original shielding by a standard disposal package and to determining the radioisotope content and activity of each one. The identification of the radionuclides and the measurement of activities will be carried out with a well type ionization chamber. This work aims to develop a methodology for measuring or to determine the activity SSRS stored in the WML accordance with its geometry and determine their uncertainties. (author)

  15. Low-level radioactive waste source terms for the 1992 integrated data base

    International Nuclear Information System (INIS)

    Loghry, S.L.; Kibbey, A.H.; Godbee, H.W.; Icenhour, A.S.; DePaoli, S.M.

    1995-01-01

    This technical manual presents updated generic source terms (i.e., unitized amounts and radionuclide compositions) which have been developed for use in the Integrated Data Base (IDB) Program of the U.S. Department of Energy (DOE). These source terms were used in the IDB annual report, Integrated Data Base for 1992: Spent Fuel and Radioactive Waste Inventories, Projections, and Characteristics, DOE/RW-0006, Rev. 8, October 1992. They are useful as a basis for projecting future amounts (volume and radioactivity) of low-level radioactive waste (LLW) shipped for disposal at commercial burial grounds or sent for storage at DOE solid-waste sites. Commercial fuel cycle LLW categories include boiling-water reactor, pressurized-water reactor, fuel fabrication, and uranium hexafluoride (UF 6 ) conversion. Commercial nonfuel cycle LLW includes institutional/industrial (I/I) waste. The LLW from DOE operations is category as uranium/thorium fission product, induced activity, tritium, alpha, and open-quotes otherclose quotes. Fuel cycle commercial LLW source terms are normalized on the basis of net electrical output [MW(e)-year], except for UF 6 conversion, which is normalized on the basis of heavy metal requirement [metric tons of initial heavy metal ]. The nonfuel cycle commercial LLW source term is normalized on the basis of volume (cubic meters) and radioactivity (curies) for each subclass within the I/I category. The DOE LLW is normalized in a manner similar to that for commercial I/I waste. The revised source terms are based on the best available historical data through 1992

  16. Hanford tank residual waste - Contaminant source terms and release models

    International Nuclear Information System (INIS)

    Deutsch, William J.; Cantrell, Kirk J.; Krupka, Kenneth M.; Lindberg, Michael L.; Jeffery Serne, R.

    2011-01-01

    Highlights: → Residual waste from five Hanford spent fuel process storage tanks was evaluated. → Gibbsite is a common mineral in tanks with high Al concentrations. → Non-crystalline U-Na-C-O-P ± H phases are common in the U-rich residual. → Iron oxides/hydroxides have been identified in all residual waste samples. → Uranium release is highly dependent on waste and leachant compositions. - Abstract: Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy's Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2-29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low ( 2 -saturated solution, or a CaCO 3 -saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO 3 -saturated solution than with the Ca(OH) 2 -saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH) 2 -saturated solution than by the CaCO 3 -saturated solution. In general, Tc is much less leachable (<10 wt.% of the

  17. Overview of waste isoltaion safety assessment program and description of source term characterization task at PNL

    International Nuclear Information System (INIS)

    Bradley, D.

    1977-01-01

    A project is being conducted to develop and illustrate the methods and obtain the data necessary to assess the safety of long-term disposal of high-level radioactive waste in geologic formations. The methods and data will initially focus on generic geologic isolation systems but will ultimately be applied to the long-term safety assessment of specific candidate sites that are selected in the NWTS Program. The activities of waste isolation safety assessment (WISAP) are divided into six tasks: (1) Safety Assessment Concepts and Methods, (2) Disruptive Event Analysis, (3) Source Characterization, (4) Transport Modeling, (5) Transport Data and (6) Societal Acceptance

  18. Development of ECR ion source for VEC

    Energy Technology Data Exchange (ETDEWEB)

    Bose, D K; Taki, G S; Nabhiraj, P Y; Pal, G; Mallik, C; Bhandari, R K [Variable Energy Cyclotron Centre, Calcutta (India)

    1997-12-01

    A 6.4 GHz Electron Cyclotron Resonance Ion Source (ECRIS) was developed at the VEC centre to enable acceleration of heavy ions with the K=130, Variable Energy Cyclotron (VEC). Heavy ions which will be sufficiently energetic after acceleration from the cyclotron will be utilised to explore new fields of research. VEC ECRIS was first made operational in April 1991. Initially the stability and intensity of high charge state (z) beam were poor. Constant efforts were paid to improve source performance. Finally going to high field operation that is improving the plasma confinement, desired stability and high output current were achieved. At present stable {sup 16}O beam up to 50 e{mu}A maximum is available from VEC ECRIS. Many other high- z ion beam of gaseous species are also available. (author) 16 refs., 14 figs., 2 tabs.

  19. Development of ECR ion source for VEC

    International Nuclear Information System (INIS)

    Bose, D.K.; Taki, G.S.; Nabhiraj, P.Y.; Pal, G.; Mallik, C.; Bhandari, R.K.

    1997-01-01

    A 6.4 GHz Electron Cyclotron Resonance Ion Source (ECRIS) was developed at the VEC centre to enable acceleration of heavy ions with the K=130, Variable Energy Cyclotron (VEC). Heavy ions which will be sufficiently energetic after acceleration from the cyclotron will be utilised to explore new fields of research. VEC ECRIS was first made operational in April 1991. Initially the stability and intensity of high charge state (z) beam were poor. Constant efforts were paid to improve source performance. Finally going to high field operation that is improving the plasma confinement, desired stability and high output current were achieved. At present stable 16 O beam up to 50 eμA maximum is available from VEC ECRIS. Many other high- z ion beam of gaseous species are also available. (author)

  20. Polarized H- source development at BNL

    International Nuclear Information System (INIS)

    Alessi, J.G.; Hershcovitch, A.; Kponou, A.; Niinikoski, T.; Sluyters, T.

    1986-01-01

    The AGS polarized H - source (PONI-1) now produces currents of 25-40 μA, and has operated reliably during polarized physics runs. A new polarized source, having as its goal mA's of H-vector, is now under development. An atomic hydrogen beam has been cooled to about 20 K with a forward flux of approx.10 19 atoms/s/sr. A superconducting solenoid having a calculated acceptance angle of 0.1 sr for the cold H 0 beam, is now being built. An ionizer for the resulting polarized H 0 beam based on resonant charge exchange of H 0 with D - , is being tested. 500 μA of H - have been produced by ionizing an unpolarized H 0 beam using this ionizer

  1. Cold source vessel development for the advanced neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Williams, P.T.; Lucas, A.T. [Oak Ridge National Lab., TN (United States)

    1995-09-01

    The Advanced Neutron Source (ANS), in its conceptual design phase at Oak Ridge National Laboratory (ORNL), will be a user-oriented neutron research facility that will produce the most intense flux of neutrons in the world. Among its many scientific applications, the productions of cold neutrons is a significant research mission for the ANS. The cold neutrons come from two independent cold sources positioned near the reactor core. Contained by an aluminum alloy vessel, each cold source is a 410 mm diameter sphere of liquid deuterium that functions both as a neutron moderator and a cryogenic coolant. With nuclear heating of the containment vessel and internal baffling, steady-state operation requires close control of the liquid deuterium flow near the vessel`s inner surface. Preliminary thermal-hydraulic analyses supporting the cold source design are being performed with multi-dimensional computational fluid dynamics simulations of the liquid deuterium flow and heat transfer. This paper presents the starting phase of a challenging program and describes the cold source conceptual design, the thermal-hydraulic feasibility studies of the containment vessel, and the future computational and experimental studies that will be used to verify the final design.

  2. Contrasting Proprietary and Free/Open Source Game Development

    Directory of Open Access Journals (Sweden)

    Marco Zamarian

    2008-10-01

    Full Text Available Free/Libre Open Source Software (F/LOSS development practices are gaining momentum in the computer game industry. This traditionally proprietary industry is becoming more interested in the F/LOSS paradigm for developing complex software projects. Software practitioners, both managers and developers, need to understand the potential in order to benefit properly from incorporating F/LOSS practices into their proprietary production cycle. Comparisons between proprietary and F/LOSS software development processes are usually characterized in terms of the relationship between property rights, revenue distribution and power within a network of actors. By contrast, coordination and control practices, mediating artifacts and development tools, and the interactions between the different actors involved in the development are often neglected. Proprietary and F/LOSS development differ in terms of the knowledge exchanges between the relevant actors and the different strategies employed to overcome information asymmetries. Recognizing this difference is an essential step for evaluating how proprietary, closed-source software houses can benefit by integrating various F/LOSS practices into their development agenda.

  3. Software development an open source approach

    CERN Document Server

    Tucker, Allen; de Silva, Chamindra

    2011-01-01

    Overview and Motivation Software Free and Open Source Software (FOSS)Two Case Studies Working with a Project Team Key FOSS Activities Client-Oriented vs. Community-Oriented Projects Working on a Client-Oriented Project Joining a Community-Oriented Project Using Project Tools Collaboration Tools Code Management Tools Run-Time System ConstraintsSoftware Architecture Architectural Patterns Layers, Cohesion, and Coupling Security Concurrency, Race Conditions, and DeadlocksWorking with Code Bad Smells and Metrics Refactoring Testing Debugging Extending the Software for a New ProjectDeveloping the D

  4. Development of solid radioactive sources in acrylamide

    International Nuclear Information System (INIS)

    Yamazaki, I.M.; Koskinas, M.F.; Dias, M.S.; Andrade e Silva, L.G.; Vieira, J.M.

    2004-01-01

    The development of water-equivalent solid sources of 133 Ba prepared from an aqueous solution of acrylamide by polymerization by a high dose 60 Co irradiation is described. The main resin characteristics were measured, such as: density, effective atomic number and uniformity. The variation of these parameters was in the range of 1,08 to 1,16 g.cm -3 for density, 3.7 to 4.0 for effective atomic number and 2.8 to 7.2% for the uniformity. These values are in agreement with the literature. (author)

  5. Accident source terms for Light-Water Nuclear Power Plants. Final report

    International Nuclear Information System (INIS)

    Soffer, L.; Burson, S.B.; Ferrell, C.M.; Lee, R.Y.; Ridgely, J.N.

    1995-02-01

    In 1962 tile US Atomic Energy Commission published TID-14844, ''Calculation of Distance Factors for Power and Test Reactors'' which specified a release of fission products from the core to the reactor containment for a postulated accident involving ''substantial meltdown of the core''. This ''source term'', tile basis for tile NRC's Regulatory Guides 1.3 and 1.4, has been used to determine compliance with tile NRC's reactor site criteria, 10 CFR Part 100, and to evaluate other important plant performance requirements. During the past 30 years substantial additional information on fission product releases has been developed based on significant severe accident research. This document utilizes this research by providing more realistic estimates of the ''source term'' release into containment, in terms of timing, nuclide types, quantities and chemical form, given a severe core-melt accident. This revised ''source term'' is to be applied to the design of future light water reactors (LWRs). Current LWR licensees may voluntarily propose applications based upon it

  6. Development of irradiator 60Co sources

    International Nuclear Information System (INIS)

    Mosca, Rodrigo C.; Moura, Eduardo S.; Zeituni, Carlos A.; Mathor, Monica B.

    2011-01-01

    According to a recent report by the International Agency for Research on Cancer (IARC) / WHO (2008-2010), the global impact of cancer more than doubled in 30 years. In this report, it was estimated that occurred about 12 million new cancer cases and 7 million deaths. In Brazil in 2010, with estimates for the year 2011, point to the occurrence of 489,270 new cases of cancer. Among the possibilities for cancer treatment, radiotherapy is one of the most important therapeutic and resources used to combat it. However, inherent complications of treatment can occur such as tiredness, loss of appetite, radiodermatitis and in more extreme cases late radionecrosis. In order to reproduce a point of radionecrosis in the vicinity of radiodermatitis to mimic these effects in animals, producing a model for assessment of tissue repair, we propose the setting up of an irradiator source of collimated 60 Co. The development of was based on 11 sources of 60 Co with 1 mm thickness that were inserted by inference in stainless steel 'gate-source' screw (patent pending) and later adjusted in a cross-shaped arrangement reinforced so that the beam radiation is directed to a target point, saving for other regions around this target point. The main use of this irradiator with sources of 60 Co is just one cause radionecrosis point (target point) of approximately 5 mm 2 with a surrounding and adjacent area of radiodermatitis around about 8 to 10 mm 2 in laboratory animals for subsequent coating with epidermal-dermal matrix populated by a cell culture of human fibroblasts, keratinocytes and mesenchymal stem cells. With that said, its use will be valuable for evaluation of curative treatments against the bone and radionecrosis or palliative treatment rather than as it is currently assumed. (author)

  7. Development of irradiator {sup 60}Co sources

    Energy Technology Data Exchange (ETDEWEB)

    Mosca, Rodrigo C.; Moura, Eduardo S.; Zeituni, Carlos A.; Mathor, Monica B., E-mail: rcmosca@usp.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    According to a recent report by the International Agency for Research on Cancer (IARC) / WHO (2008-2010), the global impact of cancer more than doubled in 30 years. In this report, it was estimated that occurred about 12 million new cancer cases and 7 million deaths. In Brazil in 2010, with estimates for the year 2011, point to the occurrence of 489,270 new cases of cancer. Among the possibilities for cancer treatment, radiotherapy is one of the most important therapeutic and resources used to combat it. However, inherent complications of treatment can occur such as tiredness, loss of appetite, radiodermatitis and in more extreme cases late radionecrosis. In order to reproduce a point of radionecrosis in the vicinity of radiodermatitis to mimic these effects in animals, producing a model for assessment of tissue repair, we propose the setting up of an irradiator source of collimated {sup 60}Co. The development of was based on 11 sources of {sup 60}Co with 1 mm thickness that were inserted by inference in stainless steel 'gate-source' screw (patent pending) and later adjusted in a cross-shaped arrangement reinforced so that the beam radiation is directed to a target point, saving for other regions around this target point. The main use of this irradiator with sources of {sup 60}Co is just one cause radionecrosis point (target point) of approximately 5 mm{sup 2} with a surrounding and adjacent area of radiodermatitis around about 8 to 10 mm{sup 2} in laboratory animals for subsequent coating with epidermal-dermal matrix populated by a cell culture of human fibroblasts, keratinocytes and mesenchymal stem cells. With that said, its use will be valuable for evaluation of curative treatments against the bone and radionecrosis or palliative treatment rather than as it is currently assumed. (author)

  8. Evaluation of applicability of alternative source terms to operating nuclear power plants in Korea

    International Nuclear Information System (INIS)

    Lim, S. N.; Park, Y. S.; Nam, K. M.; Song, D. B.; Bae, Y. J.; Lee, Y. J.; Jung, C. Y.

    2002-01-01

    In 1995 and 2000, NRC issued NUREG-1465 and Regulatory Guide 1.183 with respect to Alternative Source Terms(AST) replacing the existing source terms of TID-14844 and Regulatory Guide 1.4, 1.25, and 1.77 for radiological Design Basis Accidents(DBA) analysis. In 1990, ICRP published ICRP Pub. 60 which represents new recommendations on dose criteria and concepts. In Korea, alternative source terms were used for evaluation of effective doses for design basis accidents of Advanced Power Reactor(APR1400) using the computer program developed by an overseas company. Recently, DBADOSE, new computer program for DBA analysis incorporating AST and effective dose concept was developed by KHNP and KOPEC, and reanalysis applying AST to operating nuclear power plants, Kori units 3 and 4 in Korea using DBADOSE has been performed. As the results of this analysis, it was concluded that some conservative variables or operation procedures of operating plants could be mitigated or simplified by virtue of increased safety margin and consequently, economical and operational benefits ensue. In this paper, methodologies and results of Kori 3 and 4 DBA reanalysis and sensitivity analysis for mitigation of main design variables are introduced

  9. Quantification of uncertainties in source term estimates for a BWR with Mark I containment

    International Nuclear Information System (INIS)

    Khatib-Rahbar, M.; Cazzoli, E.; Davis, R.; Ishigami, T.; Lee, M.; Nourbakhsh, H.; Schmidt, E.; Unwin, S.

    1988-01-01

    A methodology for quantification and uncertainty analysis of source terms for severe accident in light water reactors (QUASAR) has been developed. The objectives of the QUASAR program are (1) to develop a framework for performing an uncertainty evaluation of the input parameters of the phenomenological models used in the Source Term Code Package (STCP), and (2) to quantify the uncertainties in certain phenomenological aspects of source terms (that are not modeled by STCP) using state-of-the-art methods. The QUASAR methodology consists of (1) screening sensitivity analysis, where the most sensitive input variables are selected for detailed uncertainty analysis, (2) uncertainty analysis, where probability density functions (PDFs) are established for the parameters identified by the screening stage and propagated through the codes to obtain PDFs for the outputs (i.e., release fractions to the environment), and (3) distribution sensitivity analysis, which is performed to determine the sensitivity of the output PDFs to the input PDFs. In this paper attention is limited to a single accident progression sequence, namely; a station blackout accident in a BWR with a Mark I containment buildings. Identified as an important accident in the draft NUREG-1150 a station blackout involves loss of both off-site power and DC power resulting in failure of the diesels to start and in the unavailability of the high pressure injection and core isolation coding systems

  10. 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

  11. Source terms for analysis of accidents at a high level waste repository

    International Nuclear Information System (INIS)

    Mubayi, V.; Davis, R.E.; Youngblood, R.

    1989-01-01

    This paper describes an approach to identifying source terms from possible accidents during the preclosure phase of a high-level nuclear waste repository. A review of the literature on repository safety analyses indicated that source term estimation is in a preliminary stage, largely based on judgement-based scoping analyses. The approach developed here was to partition the accident space into domains defined by certain threshold values of temperature and impact energy density which may arise in potential accidents and specify release fractions of various radionuclides, present in the waste form, in each domain. Along with a more quantitative understanding of accident phenomenology, this approach should help in achieving a clearer perspective on scenarios important to preclosure safety assessments of geologic repositories. 18 refs., 3 tabs

  12. New Source Term Model for the RESRAD-OFFSITE Code Version 3

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Charley [Argonne National Lab. (ANL), Argonne, IL (United States); Gnanapragasam, Emmanuel [Argonne National Lab. (ANL), Argonne, IL (United States); Cheng, Jing-Jy [Argonne National Lab. (ANL), Argonne, IL (United States); Kamboj, Sunita [Argonne National Lab. (ANL), Argonne, IL (United States); Chen, Shih-Yew [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-06-01

    This report documents the new source term model developed and implemented in Version 3 of the RESRAD-OFFSITE code. This new source term model includes: (1) "first order release with transport" option, in which the release of the radionuclide is proportional to the inventory in the primary contamination and the user-specified leach rate is the proportionality constant, (2) "equilibrium desorption release" option, in which the user specifies the distribution coefficient which quantifies the partitioning of the radionuclide between the solid and aqueous phases, and (3) "uniform release" option, in which the radionuclides are released from a constant fraction of the initially contaminated material during each time interval and the user specifies the duration over which the radionuclides are released.

  13. On the application of subcell resolution to conservation laws with stiff source terms

    International Nuclear Information System (INIS)

    Chang, S.

    1989-11-01

    LeVeque and Yee recently investigated a one-dimensional scalar conservation law with stiff source terms modeling the reacting flow problems and discovered that for the very stiff case most of the current finite difference methods developed for non-reacting flows would produce wrong solutions when there is a propagating discontinuity. A numerical scheme, essentially nonoscillatory/subcell resolution - characteristic direction (ENO/SRCD), is proposed for solving conservation laws with stiff source terms. This scheme is a modification of Harten's ENO scheme with subcell resolution, ENO/SR. The locations of the discontinuities and the characteristic directions are essential in the design. Strang's time-splitting method is used and time evolutions are done by advancing along the characteristics. Numerical experiment using this scheme shows excellent results on the model problem of LeVeque and Yee. Comparisons of the results of ENO, ENO/SR, and ENO/SRCD are also presented

  14. Finite volume schemes with equilibrium type discretization of source terms for scalar conservation laws

    International Nuclear Information System (INIS)

    Botchorishvili, Ramaz; Pironneau, Olivier

    2003-01-01

    We develop here a new class of finite volume schemes on unstructured meshes for scalar conservation laws with stiff source terms. The schemes are of equilibrium type, hence with uniform bounds on approximate solutions, valid in cell entropy inequalities and exact for some equilibrium states. Convergence is investigated in the framework of kinetic schemes. Numerical tests show high computational efficiency and a significant advantage over standard cell centered discretization of source terms. Equilibrium type schemes produce accurate results even on test problems for which the standard approach fails. For some numerical tests they exhibit exponential type convergence rate. In two of our numerical tests an equilibrium type scheme with 441 nodes on a triangular mesh is more accurate than a standard scheme with 5000 2 grid points

  15. Sources of Finance for Entrepreneurship Development

    Directory of Open Access Journals (Sweden)

    Balaban Mladenka

    2016-06-01

    Full Text Available Entrepreneurship is one of the most important categories that are now associated with small and medium-sized enterprises, employment and the creation of new jobs and new business category. Entrepreneurial behavior in finance implies a readiness to take risk and a taste for independence and self-fulfillment. It can develop in any sector of the economy and in any type of business. Through entrepreneurship strengthen personal resources - not only the material but also the motives of self-realization, freedom, independence, challenge. Large number of small and medium enterprises provide a huge range of products, and the customers or service users increased choice and lower prices. Considering that entrepreneurship represents the futurethis work is aimed to highlight the role the financial sector plays in its development. The authors suggest that the financial sector has very important role for the development of entrepreneurship, pointing to the different possibilities of cheaper funding development of guidelines for small and medium enterprises, but in other hand in some cases financial sector has negativ impact for growing through expensive sources of financing of development.

  16. Reassessment of the technical bases for estimating source terms. Final report

    International Nuclear Information System (INIS)

    Silberberg, M.; Mitchell, J.A.; Meyer, R.O.; Ryder, C.P.

    1986-07-01

    This document describes a major advance in the technology for calculating source terms from postulated accidents at US light-water reactors. The improved technology consists of (1) an extensive data base from severe accident research programs initiated following the TMI accident, (2) a set of coupled and integrated computer codes (the Source Term Code Package), which models key aspects of fission product behavior under severe accident conditions, and (3) a number of detailed mechanistic codes that bridge the gap between the data base and the Source Term Code Package. The improved understanding of severe accident phenonmena has also allowed an identification of significant sources of uncertainty, which should be considered in estimating source terms. These sources of uncertainty are also described in this document. The current technology provides a significant improvement in evaluating source terms over that available at the time of the Reactor Safety Study (WASH-1400) and, because of this significance, the Nuclear Regulatory Commission staff is recommending its use

  17. An appreciation of the events, models and data used for LMFBR radiological source term estimations

    International Nuclear Information System (INIS)

    Keir, D.; Clough, P.N.

    1989-01-01

    In this report, the events, models and data currently available for analysis of accident source terms in liquid metal cooled fast neutron reactors are reviewed. The types of hypothetical accidents considered are the low probability, more extreme types of severe accident, involving significant degradation of the core and which may lead to the release of radionuclides. The base case reactor design considered is a commercial scale sodium pool reactor of the CDFR type. The feasibility of an integrated calculational approach to radionuclide transport and speciation (such as is used for LWR accident analysis) is explored. It is concluded that there is no fundamental obstacle, in terms of scientific data or understanding of the phenomena involved, to such an approach. However this must be regarded as a long-term goal because of the large amount of effort still required to advance development to a stage comparable with LWR studies. Particular aspects of LMFBR severe accident phenomenology which require attention are the behaviour of radionuclides during core disruptive accident bubble formation and evolution, and during the less rapid sequences of core melt under sodium. The basic requirement for improved thermal hydraulic modelling of core, coolant and structural materials, in these and other scenarios, is highlighted as fundamental to the accuracy and realism of source term estimations. The coupling of such modelling to that of radionuclide behaviour is seen as the key to future development in this area

  18. Development of a novel methodology for indoor emission source identification

    DEFF Research Database (Denmark)

    Han, K.H.; Zhang, J.S.; Knudsen, H.N.

    2011-01-01

    The objective of this study was to develop and evaluate a methodology to identify individual sources of emissions based on the measurements of mixed air samples and the emission signatures of individual materials previously determined by Proton Transfer Reaction-Mass Spectrometry (PTR-MS), an on......-line analytical device. The methodology based on signal processing principles was developed by employing the method of multiple regression least squares (MRLS) and a normalization technique. Samples of nine typical building materials were tested individually and in combination, including carpet, ceiling material...... experiments and investigation are needed for cases where the relative emission rates among different compounds may change over a long-term period....

  19. Source term analysis for a RCRA mixed waste disposal facility

    International Nuclear Information System (INIS)

    Jordan, D.L.; Blandford, T.N.; MacKinnon, R.J.

    1996-01-01

    A Monte Carlo transport scheme was used to estimate the source strength resulting from potential releases from a mixed waste disposal facility. Infiltration rates were estimated using the HELP code, and transport through the facility was modeled using the DUST code, linked to a Monte Carlo driver

  20. Volumetric plasma source development and characterization

    International Nuclear Information System (INIS)

    Crain, Marlon D.; Maron, Yitzhak; Oliver, Bryan Velten; Starbird, Robert L.; Johnston, Mark D.; Hahn, Kelly Denise; Mehlhorn, Thomas Alan; Droemer, Darryl W.

    2008-01-01

    The development of plasma sources with densities and temperatures in the 10 15 -10 17 cm -3 and 1-10eV ranges which are slowly varying over several hundreds of nanoseconds within several cubic centimeter volumes is of interest for applications such as intense electron beam focusing as part of the x-ray radiography program. In particular, theoretical work (1,2) suggests that replacing neutral gas in electron beam focusing cells with highly conductive, pre-ionized plasma increases the time-averaged e-beam intensity on target, resulting in brighter x-ray sources. This LDRD project was an attempt to generate such a plasma source from fine metal wires. A high voltage (20-60kV), high current (12-45kA) capacitive discharge was sent through a 100 (micro)m diameter aluminum wire forming a plasma. The plasma's expansion was measured in time and space using spectroscopic techniques. Lineshapes and intensities from various plasma species were used to determine electron and ion densities and temperatures. Electron densities from the mid-10 15 to mid-10 16 cm -3 were generated with corresponding electron temperatures of between 1 and 10eV. These parameters were measured at distances of up to 1.85 cm from the wire surface at times in excess of 1 (micro)s from the initial wire breakdown event. In addition, a hydrocarbon plasma from surface contaminants on the wire was also measured. Control of these contaminants by judicious choice of wire material, size, and/or surface coating allows for the ability to generate plasmas with similar density and temperature to those given above, but with lower atomic masses

  1. Development of very large helicon plasma source

    International Nuclear Information System (INIS)

    Shinohara, Shunjiro; Tanikawa, Takao

    2004-01-01

    We have developed a very large volume, high-density helicon plasma source, 75 cm in diameter and 486 cm in axial length; full width at half maximum of the plasma density is up to ∼42 cm with good plasma uniformity along the z axis. By the use of a spiral antenna located just outside the end of the vacuum chamber through a quartz-glass window, plasma can be initiated with a very low value of radio frequency (rf) power ( 12 cm -3 is successfully produced with less than several hundred Watt; achieving excellent discharge efficiency. It is possible to control the radial density profile in this device by changing the magnetic field configurations near the antenna and/or the antenna radiation-field patterns

  2. Least-squares finite-element method for shallow-water equations with source terms

    Institute of Scientific and Technical Information of China (English)

    Shin-Jye Liang; Tai-Wen Hsu

    2009-01-01

    Numerical solution of shallow-water equations (SWE) has been a challenging task because of its nonlinear hyperbolic nature, admitting discontinuous solution, and the need to satisfy the C-property. The presence of source terms in momentum equations, such as the bottom slope and friction of bed, compounds the difficulties further. In this paper, a least-squares finite-element method for the space discretization and θ-method for the time integration is developed for the 2D non-conservative SWE including the source terms. Advantages of the method include: the source terms can be approximated easily with interpolation functions, no upwind scheme is needed, as well as the resulting system equations is symmetric and positive-definite, therefore, can be solved efficiently with the conjugate gradient method. The method is applied to steady and unsteady flows, subcritical and transcritical flow over a bump, 1D and 2D circular dam-break, wave past a circular cylinder, as well as wave past a hump. Computed results show good C-property, conservation property and compare well with exact solutions and other numerical results for flows with weak and mild gradient changes, but lead to inaccurate predictions for flows with strong gradient changes and discontinuities.

  3. Modelling and simulation the radioactive source-term of fission products in PWR type reactors

    International Nuclear Information System (INIS)

    Porfirio, Rogilson Nazare da Silva

    1996-01-01

    The source-term was defined with the purpose the quantify all radioactive nuclides released the nuclear reactor in the case of accidents. Nowadays the source-term is limited to the coolant of the primary circuit of reactors and may be measured or modelled with computer coders such as the TFP developed in this work. The calculational process is based on the linear chain techniques used in the CINDER-2 code. The TFP code considers forms of fission products release from the fuel pellet: Recoil, Knockout and Migration. The release from the gap to the coolant fluid is determined from the ratio between activity measured in the coolant and calculated activity in the gap. Considered the operational data of SURRY-1 reactor, the TFP code was run to obtain the source=term of this reactor. From the measured activities it was verified the reliability level of the model and the employed computational logic. The accuracy of the calculated quantities were compared to the measured data was considered satisfactory. (author)

  4. Determination of source terms in a degenerate parabolic equation

    International Nuclear Information System (INIS)

    Cannarsa, P; Tort, J; Yamamoto, M

    2010-01-01

    In this paper, we prove Lipschitz stability results for inverse source problems relative to parabolic equations. We use the method introduced by Imanuvilov and Yamamoto in 1998 based on Carleman estimates. What is new here is that we study a class of one-dimensional degenerate parabolic equations. In our model, the diffusion coefficient vanishes at one extreme point of the domain. Instead of the classical Carleman estimates obtained by Fursikov and Imanuvilov for non degenerate equations, we use and extend some recent Carleman estimates for degenerate equations obtained by Cannarsa, Martinez and Vancostenoble. Finally, we obtain Lipschitz stability results in inverse source problems for our class of degenerate parabolic equations both in the case of a boundary observation and in the case of a locally distributed observation

  5. Low-level waste disposal performance assessments - Total source-term analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wilhite, E.L.

    1995-12-31

    Disposal of low-level radioactive waste at Department of Energy (DOE) facilities is regulated by DOE. DOE Order 5820.2A establishes policies, guidelines, and minimum requirements for managing radioactive waste. Requirements for disposal of low-level waste emplaced after September 1988 include providing reasonable assurance of meeting stated performance objectives by completing a radiological performance assessment. Recently, the Defense Nuclear Facilities Safety Board issued Recommendation 94-2, {open_quotes}Conformance with Safety Standards at Department of Energy Low-Level Nuclear Waste and Disposal Sites.{close_quotes} One of the elements of the recommendation is that low-level waste performance assessments do not include the entire source term because low-level waste emplaced prior to September 1988, as well as other DOE sources of radioactivity in the ground, are excluded. DOE has developed and issued guidance for preliminary assessments of the impact of including the total source term in performance assessments. This paper will present issues resulting from the inclusion of all DOE sources of radioactivity in performance assessments of low-level waste disposal facilities.

  6. Regulatory impact of nuclear reactor accident source term assumptions. Technical report

    International Nuclear Information System (INIS)

    Pasedag, W.F.; Blond, R.M.; Jankowski, M.W.

    1981-06-01

    This report addresses the reactor accident source term implications on accident evaluations, regulations and regulatory requirements, engineered safety features, emergency planning, probabilistic risk assessment, and licensing practice. Assessment of the impact of source term modifications and evaluation of the effects in Design Basis Accident analyses, assuming a change of the chemical form of iodine from elemental to cesium iodide, has been provided. Engineered safety features used in current LWR designs are found to be effective for all postulated combinations of iodine source terms under DBA conditions. In terms of potential accident consequences, it is not expected that the difference in chemical form between elemental iodine and cesium iodide would be significant. In order to account for the current information on source terms, a spectrum of accident scenerios is discussed to realistically estimate the source terms resulting from a range of potential accident conditions

  7. Revised reactor accident source terms in the U.S. and implementation for light water reactors

    International Nuclear Information System (INIS)

    Soffer, L.; Lee, J.Y.

    1992-01-01

    Current NRC reactor accident source terms used for licensing are contained in Regulatory Guides 1.3 and 1.4 and specify that 100 % of the core inventory of noble gases and 25 % of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental (I 2 ) iodine. These assumptions have strongly affected present nuclear plant designs. Severe accident research results have confirmed that although the current source term is very substantial and has resulted in a very high level of plant capability, the present source term is no longer compatible with a realistic understanding of severe accidents. The NRC has issued a proposed revision of the reactor accident source terms as part of several regulatory activities to incorporate severe accident insights for future plants. A revision to 10 CFR 100 is also being proposed to specify site criteria directly and to eliminate source terms and doses for site evaluation. Reactor source terms will continue to be important in evaluating plant designs. Although intended primarily for future plants, existing and evolutionary power plants may voluntarily apply revised accident source term insights as well in licensing. The proposed revised accident source terms are presented in terms of fission product composition, magnitude, timing and iodine chemical form. Some implications for light water reactors are discussed. (author)

  8. HLW Long-term Management Technology Development

    International Nuclear Information System (INIS)

    Choi, Jong Won; Kang, C. H.; Ko, Y. K.

    2010-02-01

    Permanent disposal of spent nuclear fuels from the power generation is considered to be the unique method for the conservation of human being and nature in the present and future. In spite of spent nuclear fuels produced from power generation, based on the recent trends on the gap between supply and demand of energy, the advance on energy price and reduction of carbon dioxide, nuclear energy is expected to play a role continuously in Korea. It means that a new concept of nuclear fuel cycle is needed to solve problems on spent nuclear fuels. The concept of the advanced nuclear fuel cycle including PYRO processing and SFR was presented at the 255th meeting of the Atomic Energy Commission. According to the concept of the advanced nuclear fuel cycle, actinides and long-term fissile nuclides may go out of existence in SFR. And then it is possible to dispose of short term decay wastes without a great risk bearing. Many efforts had been made to develop the KRS for the direct disposal of spent nuclear fuels in the representative geology of Korea. But in the case of the adoption of Advanced nuclear fuel cycle, the disposal of PYRO wastes should be considered. For this, we carried out the Safety Analysis on HLW Disposal Project with 5 sub-projects such as Development of HLW Disposal System, Radwaste Disposal Safety Analysis, Feasibility study on the deep repository condition, A study on the Nuclide Migration and Retardation Using Natural Barrier, and In-situ Study on the Performance of Engineered Barriers

  9. Development of a gas-phase field ionization ion source

    International Nuclear Information System (INIS)

    Allan, G.L.; Legge, G.J.F.

    1983-01-01

    A field ionization ion source has been developed to investigate the suitability of using such a source with the Melbourne Proton Microprobe. Operating parameters have been measured, and the source has been found to be brighter than the radiofrequency ion source presently used in the Melbourne 5U Pelletron Accelerator. Improvements to the source geometry to increase the current output are planned

  10. H{sup -} radio frequency source development at the Spallation Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Welton, R. F.; Gawne, K. R.; Han, B. X.; Murray, S. N.; Pennisi, T. R.; Roseberry, R. T.; Santana, M.; Stockli, M. P. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37830-6471 (United States); Dudnikov, V. G. [Muons, Inc., 552 N. Batavia Avenue, Batavia, Illinois 60510 (United States); Turvey, M. W. [Villanova University, 800E. Lancaster Ave, Villanova, Pennsylvania 19085 (United States)

    2012-02-15

    The Spallation Neutron Source (SNS) now routinely operates nearly 1 MW of beam power on target with a highly persistent {approx}38 mA peak current in the linac and an availability of {approx}90%. H{sup -} beam pulses ({approx}1 ms, 60 Hz) are produced by a Cs-enhanced, multicusp ion source closely coupled with an electrostatic low energy beam transport (LEBT), which focuses the 65 kV beam into a radio frequency quadrupole accelerator. The source plasma is generated by RF excitation (2 MHz, {approx}60 kW) of a copper antenna that has been encased with a thickness of {approx}0.7 mm of porcelain enamel and immersed into the plasma chamber. The ion source and LEBT normally have a combined availability of {approx}99%. Recent increases in duty-factor and RF power have made antenna failures a leading cause of downtime. This report first identifies the physical mechanism of antenna failure from a statistical inspection of {approx}75 antennas which ran at the SNS, scanning electron microscopy studies of antenna surface, and cross sectional cuts and analysis of calorimetric heating measurements. Failure mitigation efforts are then described which include modifying the antenna geometry and our acceptance/installation criteria. Progress and status of the development of the SNS external antenna source, a long-term solution to the internal antenna problem, are then discussed. Currently, this source is capable of delivering comparable beam currents to the baseline source to the SNS and, an earlier version, has briefly demonstrated unanalyzed currents up to {approx}100 mA (1 ms, 60 Hz) on the test stand. In particular, this paper discusses plasma ignition (dc and RF plasma guns), antenna reliability, magnet overheating, and insufficient beam persistence.

  11. Source terms derived from analyses of hypothetical accidents, 1950-1986

    International Nuclear Information System (INIS)

    Stratton, W.R.

    1987-01-01

    This paper reviews the history of reactor accident source term assumptions. After the Three Mile Island accident, a number of theoretical and experimental studies re-examined possible accident sequences and source terms. Some of these results are summarized in this paper

  12. Source term analysis for a criticality accident in metal production line glove boxes

    International Nuclear Information System (INIS)

    Nguyen, D.H.

    1991-06-01

    A recent development in criticality accident analysis is the deterministic calculations of the transport of fission products and actinides through the barriers of the physical facility. The knowledge of the redistribution of the materials inside the facility will help determine the reentry and clean-up procedures. The amount of radioactive materials released to the environment is the source term for dispersion calculations. We have used an integrated computer model to determine the release of fission products to the environment from a hypothetical criticality event in a glove box of the metal production line (MPL) at the Lawrence Livermore National Laboratory (LLNL)

  13. Source term estimation during incident response to severe nuclear power plant accidents. Draft

    Energy Technology Data Exchange (ETDEWEB)

    McKenna, T J; Giitter, J

    1987-07-01

    The various methods of estimating radionuclide release to the environment (source terms) as a result of an accident at a nuclear power reactor are discussed. The major factors affecting potential radionuclide releases off site (source terms) as a result of nuclear power plant accidents are described. The quantification of these factors based on plant instrumentation also is discussed. A range of accident conditions from those within the design basis to the most severe accidents possible are included in the text. A method of gross estimation of accident source terms and their consequences off site is presented. The goal is to present a method of source term estimation that reflects the current understanding of source term behavior and that can be used during an event. (author)

  14. Source term estimation during incident response to severe nuclear power plant accidents. Draft

    International Nuclear Information System (INIS)

    McKenna, T.J.; Giitter, J.

    1987-01-01

    The various methods of estimating radionuclide release to the environment (source terms) as a result of an accident at a nuclear power reactor are discussed. The major factors affecting potential radionuclide releases off site (source terms) as a result of nuclear power plant accidents are described. The quantification of these factors based on plant instrumentation also is discussed. A range of accident conditions from those within the design basis to the most severe accidents possible are included in the text. A method of gross estimation of accident source terms and their consequences off site is presented. The goal is to present a method of source term estimation that reflects the current understanding of source term behavior and that can be used during an event. (author)

  15. Source term estimation during incident response to severe nuclear power plant accidents

    International Nuclear Information System (INIS)

    McKenna, T.J.; Glitter, J.G.

    1988-10-01

    This document presents a method of source term estimation that reflects the current understanding of source term behavior and that can be used during an event. The various methods of estimating radionuclide release to the environment (source terms) as a result of an accident at a nuclear power reactor are discussed. The major factors affecting potential radionuclide releases off site (source terms) as a result of nuclear power plant accidents are described. The quantification of these factors based on plant instrumentation also is discussed. A range of accident conditions from those within the design basis to the most severe accidents possible are included in the text. A method of gross estimation of accident source terms and their consequences off site is presented. 39 refs., 48 figs., 19 tabs

  16. Derivation of the source term, dose results and associated radiological consequences for the Greek Research Reactor – 1

    Energy Technology Data Exchange (ETDEWEB)

    Pappas, Charalampos, E-mail: chpappas@ipta.demokritos.gr; Ikonomopoulos, Andreas; Sfetsos, Athanasios; Andronopoulos, Spyros; Varvayanni, Melpomeni; Catsaros, Nicolas

    2014-07-01

    Highlights: • Source term derivation of postulated accident sequences in a research reactor. • Various containment ventilation scenarios considered for source term calculations. • Source term parametric analysis performed in case of lack of ventilation. • JRODOS employed for dose calculations under eighteen modeled scenarios. • Estimation of radiological consequences during typical and adverse weather scenarios. - Abstract: The estimated source term, dose results and radiological consequences of selected accident sequences in the Greek Research Reactor – 1 are presented and discussed. A systematic approach has been adopted to perform the necessary calculations in accordance with the latest computational developments and IAEA recommendations. Loss-of-coolant, reactivity insertion and fuel channel blockage accident sequences have been selected to derive the associated source terms under three distinct containment ventilation scenarios. Core damage has been conservatively assessed for each accident sequence while the ventilation has been assumed to function within the efficiency limits defined at the Safety Analysis Report. In case of lack of ventilation a parametric analysis is also performed to examine the dependency of the source term on the containment leakage rate. A typical as well as an adverse meteorological scenario have been defined in the JRODOS computational platform in order to predict the effective, lung and thyroid doses within a region defined by a 15 km radius downwind from the reactor building. The radiological consequences of the eighteen scenarios associated with the accident sequences are presented and discussed.

  17. Operator aids for prediction of source term attenuation

    International Nuclear Information System (INIS)

    Powers, D.A.

    2004-01-01

    Simplified expressions for the attenuation of radionuclide releases by sprays and by water pools are devised. These expressions are obtained by correlation of the 10th, 50th and 90th percentiles of uncertainty distributions for the water pool decontamination factor and the spray decontamination coefficient. These uncertainty distributions were obtained by Monte Carlo uncertainty analyses using detailed, mechanistic models of the pools and sprays. Uncertainties considered in the analyses include uncertainties in the phenomena and uncertainties in the initial and boundary conditions dictated by the progression of severe accidents. Final results are graphically displayed in terms of the decontamination factor achieved at selected levels of conservatism versus pool depth and water subcooling or, in the case of sprays, versus time. (author)

  18. Development of the Sources of Spirituality Scale.

    Science.gov (United States)

    Davis, Don E; Rice, Kenneth; Hook, Joshua N; Van Tongeren, Daryl R; DeBlaere, Cirleen; Choe, Elise; Worthington, Everett L

    2015-07-01

    Most measures of spirituality privilege religious spirituality, but people may experience spirituality in a variety of ways, including a sense of closeness, oneness, or connection with a theistic being, the transcendent (i.e., something outside space and time), oneself, humanity, or nature. The overall purpose of the present 4 studies was to develop the Sources of Spirituality (SOS) Scale to measure these different elements of spirituality. In Study 1, we created items, had them reviewed by experts, and used data from a sample of undergraduates (N = 218) to evaluate factor structure and inform initial measurement revisions. The factor structure replicated well in another sample of undergraduates (N = 200; Study 2), and in a sample of community adults (N = 140; Study 3). In a sample of undergraduates (N = 200; Study 4), we then evaluated evidence of construct validity by examining associations between SOS Scale scores and religious commitment, positive attitudes toward the Sacred, and dispositional connection with nature. Moreover, based on latent profile analyses results, we found 5 distinct patterns of spirituality based on SOS subscales. We consider implications for therapy and relevance of the findings for models of spirituality and future research. (c) 2015 APA, all rights reserved).

  19. Prospects of renewable energy sources in India: Prioritization of alternative sources in terms of Energy Index

    International Nuclear Information System (INIS)

    Jha, Shibani K.; Puppala, Harish

    2017-01-01

    The growing energy demand in progressing civilization governs the exploitation of various renewable sources over the conventional sources. Wind, Solar, Hydro, Biomass, and waste & Bagasse are the various available renewable sources in India. A reliable nonconventional geothermal source is also available in India but it is restricted to direct heat applications. This study archives the status of renewable alternatives in India. The techno economic factors and environmental aspects associated with each of these alternatives are discussed. This study focusses on prioritizing the renewable sources based on a parameter introduced as Energy Index. This index is evaluated using cumulative scores obtained for each of the alternatives. The cumulative score is obtained by evaluating each alternative over a range of eleven environmental and techno economic criteria following Fuzzy Analytical Hierarchy Process. The eleven criteria's considered in the study are Carbon dioxide emissions (CO 2 ), Sulphur dioxide emissions (SO 2 ), Nitrogen oxide emissions (NO x ), Land requirement, Current energy cost, Potential future energy cost, Turnkey investment, Capacity factor, Energy efficiency, Design period and Water consumption. It is concluded from the study that the geothermal source is the most preferable alternative with highest Energy Index. Hydro, Wind, Biomass and Solar sources are subsequently preferred alternatives. - Highlights: • FAH process is used to obtain cumulative score for each renewable alternative. • Cumulative score is normalized by highest score of ideal source. • Energy Index shows how best a renewable alternative is. • Priority order is obtained for alternatives based on Energy Index. • Geothermal is most preferable source followed by Hydro, Wind, Biomass and Solar.

  20. Info Source | IDRC - International Development Research Centre

    International Development Research Centre (IDRC) Digital Library (Canada)

    Info Source: Sources of Federal Government and Employee Information provides ... Bringing together the right partners around opportunities for impact, IDRC builds ... Internal services constitute groups of related activities and resources that are ... including planning, budgeting, accounting, reporting, control and oversight, ...

  1. An Organizational-Technical Concept to Deal with Open Source Software License Terms

    Directory of Open Access Journals (Sweden)

    Sergius Dyck

    2016-06-01

    Full Text Available Open source software (OSS released under various license terms is widely used as third party libraries in today's software projects. To ensure open source compliance within an organization, a strategic approach to OSS management is needed. As basis for such an approach, we introduce an organizational-technical concept for dealing with the various OSS licenses by using procedural instructions and build automation software. The concept includes the careful consideration of OSS license conditions. The results obtained from this consideration and additional necessary commitments are documented in a so-called license playbook. We introduce procedure instructions enabling a consistent approach for software development using OSS libraries. The procedure instructions are described in a way such that they can be implemented for example for Java projects using the popular build automation tool Apache Maven and the software repository tool Nexus. We give guidance on how to realize such an implementation on basis of automation tools in practice.

  2. The Multimedia Environmental Pollutant Assessment System (MEPAS)reg-sign: Source-term release formulations

    International Nuclear Information System (INIS)

    Streile, G.P.; Shields, K.D.; Stroh, J.L.; Bagaasen, L.M.; Whelan, G.; McDonald, J.P.; Droppo, J.G.; Buck, J.W.

    1996-11-01

    This report is one of a series of reports that document the mathematical models in the Multimedia Environmental Pollutant Assessment System (MEPAS). Developed by Pacific Northwest National Laboratory for the US Department of Energy, MEPAS is an integrated impact assessment software implementation of physics-based fate and transport models in air, soil, and water media. Outputs are estimates of exposures and health risk assessments for radioactive and hazardous pollutants. Each of the MEPAS formulation documents covers a major MEPAS component such as source-term, atmospheric, vadose zone/groundwater, surface water, and health exposure/health impact assessment. Other MEPAS documentation reports cover the sensitivity/uncertainty formulations and the database parameter constituent property estimation methods. The pollutant source-term release component is documented in this report. MEPAS simulates the release of contaminants from a source, transport through the air, groundwater, surface water, or overland pathways, and transfer through food chains and exposure pathways to the exposed individual or population. For human health impacts, risks are computed for carcinogens and hazard quotients for noncarcinogens. MEPAS is implemented on a desktop computer with a user-friendly interface that allows the user to define the problem, input the required data, and execute the appropriate models for both deterministic and probabilistic analyses

  3. Plan of promotion and development of unconventional renewable sources

    International Nuclear Information System (INIS)

    Rojas M, Jose Rodrigo

    2016-01-01

    The plan for the promotion and development of unconventional sources renewable energies developed by the Instituto Costarricense de Electricidad is explained. The percentage data from the use of unconventional renewable sources for power generation in Costa Rica is presented [es

  4. The ion source development for neutral injection heating at JAERI

    International Nuclear Information System (INIS)

    Shirakata, H.; Itoh, T.; Kondoh, U.; Matsuda, S.; Ohara, Y.; Ohga, T.; Shibata, T.; Sugawara, T.; Tanaka, S.

    1976-01-01

    The neutral beam research and development effort at JAERI has been mainly concentrated on design, construction and testing of ion sources needed for present and planned heating experiments. Fundamental characteristics of the ion sources developed are described

  5. Source term reduction at DAEC (including stellite ball recycling)

    International Nuclear Information System (INIS)

    Smith, R.; Schebler, D.

    1995-01-01

    The Duane Arnold Energy Center was seeking methods to reduce dose rates from the drywell due to Co-60. Duane Arnold is known in the industry to have one of the highest drywell dose rates from the industry standardized 'BRAC' point survey. A prime method to reduce dose rates due to Co-60 is the accelerated replacement of stellite pins and rollers in control rod blades due to their high stellite (cobalt) content. Usually the cobalt content in alloys of stellite is greater than 60% cobalt by weight. During the RFO-12 refueling outage at Duane Arnold, all of the remaining cobalt bearing control rod blades were replaced and new stellite free control rod blades were installed in the core. This left Duane Arnold with the disposal of highly radioactive stellite pins and rollers. The processing of control rod blades for disposal is a very difficult evolution. First, the velocity limiter (a bottom portion of the component) and the highly radioactive upper stellite control rod blade ins and rollers are separated from the control rod blade. Next, the remainder of the control rod blade is processed (chopped and/or crushed) to aid packaging the waste for disposal. The stellite bearings are then often carefully placed in with the rest of the waste in a burial liner to provide shielding for disposal or more often are left as 'orphans' in the spent fuel pool because their high specific activity create shipping and packaging problems. Further investigation by the utility showed that the stellite balls and pins could be recycled to a source manufacturer rather than disposed of in a low-level burial site. The cost savings to the utility was on the order of $200,000 with a gross savings of $400,000 in savings in burial site charges. A second advantage of the recycling of the stellite pins and rollers was a reduction in control in radioactive waste shipments

  6. Jet flow analysis of liquid poison injection in a CANDU reactor using source term

    International Nuclear Information System (INIS)

    Chae, Kyung Myung; Choi, Hang Bok; Rhee, Bo Wook

    2001-01-01

    For the performance analysis of Canadian deuterium uranium (CANDU) reactor shutdown system number 2 (SDS2), a computational fluid dynamics model of poison jet flow has been developed to estimate the flow field and poison concentration formed inside the CANDU reactor calandria. As the ratio of calandria shell radius over injection nozzle hole diameter is so large (1055), it is impractical to develop a full-size model encompassing the whole calandria shell. In order to reduce the model to a manageable size, a quarter of one-pitch length segment of the shell was modeled using symmetric nature of the jet; and the injected jet was treated as a source term to avoid the modeling difficulty caused by the big difference of the hole sizes. For the analysis of an actual CANDU-6 SDS2 poison injection, the grid structure was determined based on the results of two-dimensional real- and source-jet simulations. The maximum injection velocity of the liquid poison is 27.8 m/s and the mass fraction of the poison is 8000 ppm (mg/kg). The simulation results have shown well-established jet flow field. In general, the jet develops narrowly at first but stretches rapidly. Then, the flow recirculates a little in r-x plane, while it recirculates largely in r-θ plane. As the time goes on, the adjacent jets contact each other and form a wavy front such that the whole jet develops in a plate form. his study has shown that the source term model can be effectively used for the analysis of the poison injection and the simulation result of the CANDU reactor is consistent with the model currently being used for the safety analysis. In the future, it is strongly recommended to analyze the transient (from helium tank to injection nozzle hole) of the poison injection by applying Bernoulli equation with real boundary conditions

  7. Source term for the bounding assessment of the Canadian nuclear fuel waste disposal concept

    International Nuclear Information System (INIS)

    Flavelle, P.

    1996-02-01

    This is the second in a series to derive the bounds of the post-closure hazard of the Canadian nuclear fuel waste disposal concept, based on the premise that it is unnecessary to predict accurately the real hazard if the bounding hazard can be shown to be acceptable. In this report a reference used (Bruce A fuel, 865 GJ/kgU average burnup) is used to derive the source term for contaminant releases from the emplacement canisters. This requires development of a container failure function which defines the age of the fuel when the canister is perforated and flooded. The source term is expressed as the time-dependent fractional release rate from the used fuel or as the time-dependent contaminant concentrations in the canister porewater. It is derived as the superposition of an instant release, comprising the upper bound of the gap and grain boundary inventory in the used fuel, and the long-term dissolution of the used fuel matrix. Several dissolution models (stoichiometric dissolution/preferential leaching) under different conditions (matrix solubility limited/ unlimited; oxidizing/ reducing solubility limits; groundwater flow/ no flow) are evaluated and the one resulting in the highest release rate/ highest porewater concentration is adopted as the bounding case. Comparisons between the models are made on the basis of the potential ingestion hazard of the canister porewater, to account for differences in the hazard of different radionuclides. (author) 20 refs., 4 tabs., 9 figs

  8. PHENOstruct: Prediction of human phenotype ontology terms using heterogeneous data sources.

    Science.gov (United States)

    Kahanda, Indika; Funk, Christopher; Verspoor, Karin; Ben-Hur, Asa

    2015-01-01

    The human phenotype ontology (HPO) was recently developed as a standardized vocabulary for describing the phenotype abnormalities associated with human diseases. At present, only a small fraction of human protein coding genes have HPO annotations. But, researchers believe that a large portion of currently unannotated genes are related to disease phenotypes. Therefore, it is important to predict gene-HPO term associations using accurate computational methods. In this work we demonstrate the performance advantage of the structured SVM approach which was shown to be highly effective for Gene Ontology term prediction in comparison to several baseline methods. Furthermore, we highlight a collection of informative data sources suitable for the problem of predicting gene-HPO associations, including large scale literature mining data.

  9. Ion Source Development at the SNS

    International Nuclear Information System (INIS)

    Welton, R. F.; Han, B. X.; Kenik, E. A.; Murray, S. N.; Pennisi, T. R.; Potter, K. G.; Lang, B. R.; Santana, M.; Stockli, M. P.; Desai, N. J.

    2011-01-01

    The Spallation Neutron Source (SNS) now routinely operates near 1 MW of beam power on target with a highly-persistent ∼38 mA peak current in the linac and an availability of ∼90%. The ∼1 ms-long, 60 Hz, ∼50 mA H - beam pulses are extracted from a Cs-enhanced, multi-cusp, RF-driven, internal-antenna ion source. An electrostatic LEBT (Low Energy Beam Transport) focuses the 65 kV beam into the RFQ accelerator. The ion source and LEBT have normally a combined availability of ∼99%. Although much progress has been made over the last years to achieve this level of availability further improvements are desirable. Failures of the internal antenna and occasionally impaired electron dump insulators require several source replacements per year. An attempt to overcome the antenna issues with an AlN external antenna source early in 2009 had to be terminated due to availability issues. This report provides a comprehensive review of the design, experimental history, status, and description of recently updated components and future plans for this ion source. The mechanical design for improved electron dump vacuum feedthroughs is also presented, which is compatible with the baseline and both external antenna ion sources.

  10. ANL calculational methodologies for determining spent nuclear fuel source term

    International Nuclear Information System (INIS)

    McKnight, R. D.

    2000-01-01

    Over the last decade Argonne National Laboratory has developed reactor depletion methods and models to determine radionuclide inventories of irradiated EBR-II fuels. Predicted masses based on these calculational methodologies have been validated using available data from destructive measurements--first from measurements of lead EBR-II experimental test assemblies and later using data obtained from processing irradiated EBR-II fuel assemblies in the Fuel Conditioning Facility. Details of these generic methodologies are described herein. Validation results demonstrate these methods meet the FCF operations and material control and accountancy requirements

  11. Vacuum ARC ion sources - activities ampersand developments at LBL

    International Nuclear Information System (INIS)

    Brown, I.

    1996-01-01

    The author describes work at LBL on the development and application of vacuum arc ion sources. Work has been done on vacuum spark sources - to produce very high charge states, studies of high charge states in magnetic field, hybrid ion source operation on metal/gas plasma, multipole operation, work on MEVVA V for implantation applications, development of broad beam sources, and removal of particles from the output of the source

  12. Inverse modeling of the Chernobyl source term using atmospheric concentration and deposition measurements

    Science.gov (United States)

    Evangeliou, Nikolaos; Hamburger, Thomas; Cozic, Anne; Balkanski, Yves; Stohl, Andreas

    2017-07-01

    This paper describes the results of an inverse modeling study for the determination of the source term of the radionuclides 134Cs, 137Cs and 131I released after the Chernobyl accident. The accident occurred on 26 April 1986 in the Former Soviet Union and released about 1019 Bq of radioactive materials that were transported as far away as the USA and Japan. Thereafter, several attempts to assess the magnitude of the emissions were made that were based on the knowledge of the core inventory and the levels of the spent fuel. More recently, when modeling tools were further developed, inverse modeling techniques were applied to the Chernobyl case for source term quantification. However, because radioactivity is a sensitive topic for the public and attracts a lot of attention, high-quality measurements, which are essential for inverse modeling, were not made available except for a few sparse activity concentration measurements far from the source and far from the main direction of the radioactive fallout. For the first time, we apply Bayesian inversion of the Chernobyl source term using not only activity concentrations but also deposition measurements from the most recent public data set. These observations refer to a data rescue attempt that started more than 10 years ago, with a final goal to provide available measurements to anyone interested. In regards to our inverse modeling results, emissions of 134Cs were estimated to be 80 PBq or 30-50 % higher than what was previously published. From the released amount of 134Cs, about 70 PBq were deposited all over Europe. Similar to 134Cs, emissions of 137Cs were estimated as 86 PBq, on the same order as previously reported results. Finally, 131I emissions of 1365 PBq were found, which are about 10 % less than the prior total releases. The inversion pushes the injection heights of the three radionuclides to higher altitudes (up to about 3 km) than previously assumed (≈ 2.2 km) in order to better match both concentration

  13. Inverse modeling of the Chernobyl source term using atmospheric concentration and deposition measurements

    Directory of Open Access Journals (Sweden)

    N. Evangeliou

    2017-07-01

    Full Text Available This paper describes the results of an inverse modeling study for the determination of the source term of the radionuclides 134Cs, 137Cs and 131I released after the Chernobyl accident. The accident occurred on 26 April 1986 in the Former Soviet Union and released about 1019 Bq of radioactive materials that were transported as far away as the USA and Japan. Thereafter, several attempts to assess the magnitude of the emissions were made that were based on the knowledge of the core inventory and the levels of the spent fuel. More recently, when modeling tools were further developed, inverse modeling techniques were applied to the Chernobyl case for source term quantification. However, because radioactivity is a sensitive topic for the public and attracts a lot of attention, high-quality measurements, which are essential for inverse modeling, were not made available except for a few sparse activity concentration measurements far from the source and far from the main direction of the radioactive fallout. For the first time, we apply Bayesian inversion of the Chernobyl source term using not only activity concentrations but also deposition measurements from the most recent public data set. These observations refer to a data rescue attempt that started more than 10 years ago, with a final goal to provide available measurements to anyone interested. In regards to our inverse modeling results, emissions of 134Cs were estimated to be 80 PBq or 30–50 % higher than what was previously published. From the released amount of 134Cs, about 70 PBq were deposited all over Europe. Similar to 134Cs, emissions of 137Cs were estimated as 86 PBq, on the same order as previously reported results. Finally, 131I emissions of 1365 PBq were found, which are about 10 % less than the prior total releases. The inversion pushes the injection heights of the three radionuclides to higher altitudes (up to about 3 km than previously assumed (≈ 2.2 km in order

  14. SARNET. Severe Accident Research Network - key issues in the area of source term

    International Nuclear Information System (INIS)

    Giordano, P.; Micaelli, J.C.; Haste, T.; Herranz, L.

    2005-01-01

    About fifty European organisations integrate in SARNET (Network of Excellence of the EU 6 th Framework Programme) their research capacities in resolve better the most important remaining uncertainties and safety issues concerning existing and future Nuclear Power Plants (NPPs) under hypothetical Severe Accident (SA) conditions. Wishing to maintain a long-lasting cooperation, they conduct three types of activities: integrating activities, spreading of excellence and jointly executed research. This paper summarises the main results obtained by the network after the first year, giving more prominence to those from jointly executed research in the Source Term area. Integrating activities have been performed through different means: the ASTEC integral computer code for severe accident transient modelling, through development of PSA2 methodologies, through the setting of a structure for definition of evolving R and D priorities and through the development of a web-network of data bases that hosts experimental data. Such activities have been facilitated by the development of an Advanced Communication Tool. Concerning spreading of excellence, educational courses covering Severe Accident Analysis Methodology and Level 2 PSA have been set up, to be given in early 2006. A detailed text book on Severe Accident Phenomenology has been designed and agreed amongst SARNET members. A mobility programme for students and young researchers is being developed, some detachments are already completed or in progress, and examples are quoted. Jointly executed research activities concern key issues grouped in the Corium, Containment and Source Term areas. In Source Term, behaviour of the highly radio-toxic ruthenium under oxidising conditions (like air ingress) for HBU and MOX fuel has been investigated. First modelling proposals for ASTEC have been made for oxidation of fuel and of ruthenium. Experiments on transport of highly volatile oxide ruthenium species have been performed. Reactor

  15. Some developments in polarized ion sources

    International Nuclear Information System (INIS)

    Witteveen, G.J.

    1979-01-01

    Investigations concerning an atomic beam source are presented and a new polarized ion source of a more universal type is introduced. Polarized and unpolarized beams of positively or negatively charged ions can be produced with this new version and the theoretical limits are a polarized negative hydrogen ion beam with an intensity of about 1 mH and a polarized proton beam with an intensity of 10 mH. (C.F.)

  16. The Analytical Repository Source-Term (AREST) model: Description and documentation

    International Nuclear Information System (INIS)

    Liebetrau, A.M.; Apted, M.J.; Engel, D.W.; Altenhofen, M.K.; Strachan, D.M.; Reid, C.R.; Windisch, C.F.; Erikson, R.L.; Johnson, K.I.

    1987-10-01

    The geologic repository system consists of several components, one of which is the engineered barrier system. The engineered barrier system interfaces with natural barriers that constitute the setting of the repository. A model that simulates the releases from the engineered barrier system into the natural barriers of the geosphere, called a source-term model, is an important component of any model for assessing the overall performance of the geologic repository system. The Analytical Repository Source-Term (AREST) model being developed is one such model. This report describes the current state of development of the AREST model and the code in which the model is implemented. The AREST model consists of three component models and five process models that describe the post-emplacement environment of a waste package. All of these components are combined within a probabilistic framework. The component models are a waste package containment (WPC) model that simulates the corrosion and degradation processes which eventually result in waste package containment failure; a waste package release (WPR) model that calculates the rates of radionuclide release from the failed waste package; and an engineered system release (ESR) model that controls the flow of information among all AREST components and process models and combines release output from the WPR model with failure times from the WPC model to produce estimates of total release. 167 refs., 40 figs., 12 tabs

  17. Recent advances in the source term area within the SARNET European severe accident research network

    International Nuclear Information System (INIS)

    Herranz, L.E.; Haste, T.; Kärkelä, T.

    2015-01-01

    Highlights: • Main achievements of source term research in SARNET are given. • Emphasis on the radiologically important iodine and ruthenium fission products. • Conclusions on FP release, transport in the RCS and containment behaviour. • Significance of large-scale integral experiments to validate the analyses used. • A thorough list of the most recent references on source term research results. - Abstract: Source Term has been one of the main research areas addressed within the SARNET network during the 7th EC Framework Programme of EURATOM. The entire source term domain was split into three major areas: oxidising impact on source term, iodine chemistry in the reactor coolant system and containment and data and code assessment. The present paper synthesises the main technical outcome stemming from the SARNET FWP7 project in the area of source term and includes an extensive list of references in which deeper insights on specific issues may be found. Besides, based on the analysis of the current state of the art, an outlook of future source term research is outlined, where major changes in research environment are discussed (i.e., the end of the Phébus FP project; the end of the SARNET projects; and the launch of HORIZON 2020). Most probably research projects will be streamlined towards: release and transport under oxidising conditions, containment chemistry, existing and innovative filtered venting systems and others. These will be in addition to a number of projects that have been completed or are ongoing under different national and international frameworks, like VERDON, CHIP and EPICUR started under the International Source Term Programme (ISTP), the OECD/CSNI programmes BIP, BIP2, STEM, THAI and THAI2, and the French national programme MIRE. The experimental PASSAM project under the 7th EC Framework programme, focused on source term mitigation systems, is highlighted as a good example of a project addressing potential enhancement of safety systems

  18. Recent advances in the source term area within the SARNET European severe accident research network

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, L.E., E-mail: luisen.herranz@ciemat.es [Centro de Investigaciones Energeticas Medio Ambientales y Tecnologica, CIEMAT, Avda. Complutense 40, E-28040 Madrid (Spain); Haste, T. [Institut de Radioprotection et de Sûreté Nucléaire, IRSN, BP 3, F-13115 St Paul lez Durance Cedex (France); Kärkelä, T. [VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT Espoo (Finland)

    2015-07-15

    Highlights: • Main achievements of source term research in SARNET are given. • Emphasis on the radiologically important iodine and ruthenium fission products. • Conclusions on FP release, transport in the RCS and containment behaviour. • Significance of large-scale integral experiments to validate the analyses used. • A thorough list of the most recent references on source term research results. - Abstract: Source Term has been one of the main research areas addressed within the SARNET network during the 7th EC Framework Programme of EURATOM. The entire source term domain was split into three major areas: oxidising impact on source term, iodine chemistry in the reactor coolant system and containment and data and code assessment. The present paper synthesises the main technical outcome stemming from the SARNET FWP7 project in the area of source term and includes an extensive list of references in which deeper insights on specific issues may be found. Besides, based on the analysis of the current state of the art, an outlook of future source term research is outlined, where major changes in research environment are discussed (i.e., the end of the Phébus FP project; the end of the SARNET projects; and the launch of HORIZON 2020). Most probably research projects will be streamlined towards: release and transport under oxidising conditions, containment chemistry, existing and innovative filtered venting systems and others. These will be in addition to a number of projects that have been completed or are ongoing under different national and international frameworks, like VERDON, CHIP and EPICUR started under the International Source Term Programme (ISTP), the OECD/CSNI programmes BIP, BIP2, STEM, THAI and THAI2, and the French national programme MIRE. The experimental PASSAM project under the 7th EC Framework programme, focused on source term mitigation systems, is highlighted as a good example of a project addressing potential enhancement of safety systems

  19. The severe accidents and source term problems approach in France

    International Nuclear Information System (INIS)

    Bussac, J.; Cogne, F.; Pelce, J.

    1986-01-01

    The French methodology described in this report aims at providing operators with a comprehensive body which should enable them to tackle any situation or type of accident whose occurrence does not appear to be physically unconceivable. It is no longer considered that the early failure of the containment can result from a conceivable accidental sequence and is therefore no longer taken into consideration, except, however, when examining and selecting the site criteria. Prevention measures and relatively inexpensive remedies allow a substantial reduction in the probability of core melting and, if melting occurs, in the probability of loss of leaktightness and the level of possible releases out of the containment. This implies very special attention to accident management and operators' actions, to which great importance is attached. We must not stop research because of the lack of experimental data concerning problems which have not yet been completely settled and there is a real need for an integral check program for the code systems existing or in development

  20. Neutronics of the IFMIF neutron source: development and analysis

    International Nuclear Information System (INIS)

    Wilson, P.P.H.

    1999-01-01

    The accurate analysis of this system required the development of a code system and methodology capable of modelling the various physical processes. A generic code system for the neutronics analysis of neutron sources has been created by loosely integrating existing components with new developments: the data processing code NJOY, the Monte Carlo neutron transport code MCNP, and the activation code ALARA were supplemented by a damage data processing program, damChar, and integrated with a number of flexible and extensible modules for the Perl scripting language. Specific advances were required to apply this code system to IFMIF. Based on the ENDF-6 data format requirements of this system, new data evaluations have been implemented for neutron transport and activation. Extensive analysis of the Li(d, xn) reaction has led to a new MCNP source function module, M c DeLi, based on physical reaction models and capable of accurate and flexible modelling of the IFMIF neutron source term. In depth analyses of the neutron flux spectra and spatial distribution throughout the high flux test region permitted a basic validation of the tools and data. The understanding of the features of the neutron flux provided a foundation for the analyses of the other neutron responses. (orig./DGE) [de

  1. Source term model evaluations for the low-level waste facility performance assessment

    Energy Technology Data Exchange (ETDEWEB)

    Yim, M.S.; Su, S.I. [North Carolina State Univ., Raleigh, NC (United States)

    1995-12-31

    The estimation of release of radionuclides from various waste forms to the bottom boundary of the waste disposal facility (source term) is one of the most important aspects of LLW facility performance assessment. In this work, several currently used source term models are comparatively evaluated for the release of carbon-14 based on a test case problem. The models compared include PRESTO-EPA-CPG, IMPACTS, DUST and NEFTRAN-II. Major differences in assumptions and approaches between the models are described and key parameters are identified through sensitivity analysis. The source term results from different models are compared and other concerns or suggestions are discussed.

  2. Source-term reevaluation for US commercial nuclear power reactors: a status report

    International Nuclear Information System (INIS)

    Herzenberg, C.L.; Ball, J.R.; Ramaswami, D.

    1984-12-01

    Only results that had been discussed publicly, had been published in the open literature, or were available in preliminary reports as of September 30, 1984, are included here. More than 20 organizations are participating in source-term programs, which have been undertaken to examine severe accident phenomena in light-water power reactors (including the chemical and physical behavior of fission products under accident conditions), update and reevaluate source terms, and resolve differences between predictions and observations of radiation releases and related phenomena. Results from these source-term activities have been documented in over 100 publications to date

  3. An investigation of the closure problem applied to reactor accident source terms

    International Nuclear Information System (INIS)

    Brearley, I.R.; Nixon, W.; Hayns, M.R.

    1987-01-01

    The closure problem, as considered here, focuses attention on the question of when in current research programmes enough has been learned about the source terms for reactor accident releases. Noting that current research is tending to reduce the estimated magnitude of the aerosol component of atmospheric, accidental releases, several possible criteria for closure are suggested. Moreover, using the reactor accident consequence model CRACUK, the effect of gradually reducing the aerosol release fractions of a pressurized water reactor (PWR2) source term (as defined in the WASH-1400 study) is investigated and the implications of applying the suggested criteria to current source term research discussed. (author)

  4. Evaluation of the LMFBR cover gas source term and synthesis of the associated R and D

    International Nuclear Information System (INIS)

    Balard, F.; Carluec, B.

    1996-01-01

    At the end of the seventies and the beginning of the eighties, there appeared a pressing need of experimental results to assess the LMFBR's safety level. Because of the urgency, analytical studies were not systematically undertaken and maximum credible cover gas instantaneous source terms (radionuclides core release fraction) were got directly from crude out-of-pile experiment interpretations. Two types of studies and mock-ups were undertaken depending on the timescale of the phenomena: instantaneous source terms (corresponding to an unlikely energetic core disruptive accident CDA), and delayed ones (tens of minutes to some hours). The experiments performed in this frame are reviewed in this presentation: 1) instantaneous source term: - FAUST experiments: I, Cs, UO2 source terms (FzK, Germany), - FAST experiments : pool depth influence on non volatile source term (USA), - CARAVELLE experiments: nonvolatile source term in SPX1 geometry (CEA, France); 2) delayed source term: - NALA experiments: I, Cs, Sr, UO2 source term (FzK, Germany), - PAVE experiments: I source term (CEA, France), - NACOWA experiments: cover gas aerosols enrichment in I and Cs (FzK, Germany) - other French experiments in COPACABANA and GULLIVER facilities. The volatile fission products release is tightly bound to sodium evaporation and a large part of the fission products is dissolved in the liquid sodium aerosols present in the cover gas. Thus the knowledge of the amount of aerosol release to the cover gas is important for the evaluation of the source term. The maximum credible cover gas instantaneous source terms deduced from the experiments have led to conservative source terms to be taken into account in safety analysis. Nevertheless modelling attempts of the observed (in-pile or out-of-pile) physico-chemical phenomena have been undertaken for extrapolation to the reactor case. The main topics of this theoretical research are as follows: fission products evaporation in the cover gas (Fz

  5. ORIGAMI Automator Primer. Automated ORIGEN Source Terms and Spent Fuel Storage Pool Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wieselquist, William A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Thompson, Adam B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peterson, Joshua L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    Source terms and spent nuclear fuel (SNF) storage pool decay heat load analyses for operating nuclear power plants require a large number of Oak Ridge Isotope Generation and Depletion (ORIGEN) calculations. SNF source term calculations also require a significant amount of bookkeeping to track quantities such as core and assembly operating histories, spent fuel pool (SFP) residence times, heavy metal masses, and enrichments. The ORIGEN Assembly Isotopics (ORIGAMI) module in the SCALE code system provides a simple scheme for entering these data. However, given the large scope of the analysis, extensive scripting is necessary to convert formats and process data to create thousands of ORIGAMI input files (one per assembly) and to process the results into formats readily usable by follow-on analysis tools. This primer describes a project within the SCALE Fulcrum graphical user interface (GUI) called ORIGAMI Automator that was developed to automate the scripting and bookkeeping in large-scale source term analyses. The ORIGAMI Automator enables the analyst to (1) easily create, view, and edit the reactor site and assembly information, (2) automatically create and run ORIGAMI inputs, and (3) analyze the results from ORIGAMI. ORIGAMI Automator uses the standard ORIGEN binary concentrations files produced by ORIGAMI, with concentrations available at all time points in each assembly’s life. The GUI plots results such as mass, concentration, activity, and decay heat using a powerful new ORIGEN Post-Processing Utility for SCALE (OPUS) GUI component. This document includes a description and user guide for the GUI, a step-by-step tutorial for a simplified scenario, and appendices that document the file structures used.

  6. Estimation of Source Term Behaviors in SBO Sequence in a Typical 1000MWth PWR and Comparison with Other Source Term Results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Woon; Han, Seok Jung; Ahn, Kwang Il; Fynan, Douglas; Jung, Yong Hoon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    Since the Three Mile Island (TMI) (1979), Chernobyl (1986), Fukushima Daiichi (2011) accidents, the assessment of radiological source term effects on the environment has been a key concern of nuclear safety. In the Fukushima Daiichi accident, the long-term SBO (station blackout) accident occurs. Using the worst case assumptions like in Fukushima accident on the accident sequences and on the availability of safety systems, the thermal hydraulic behaviors, core relocation and environmental source terms behaviors are estimated for long-term SBO accident for OPR-1000 reactor. MELCOR code version 1.8.6 is used in this analysis. Source term results estimated in this study is compared with other previous studies and estimated results in Fukushima accidents in UNSCEAR-2013 report. This study estimated that 11 % of iodine can be released to environment and 2% of cesium can be released to environment. UNSCEAR-2013 report estimated that 2 - 8 % of iodine have been released to environment and 1 - 3 % of cesium have been released to the environment. They have similar results in the aspect of release fractions of iodine and cesium to environment.

  7. New developments in RF power sources

    International Nuclear Information System (INIS)

    Miller, R.H.

    1994-06-01

    The most challenging rf source requirements for high-energy accelerators presently being studied or designed come from the various electron-positron linear collider studies. All of these studies except TESLA (the superconducting entry in the field) have specified rf sources with much higher peak powers than any existing tubes at comparable high frequencies. While circular machines do not, in general, require high peak power, the very high luminosity electron-positron rings presently being designed as B factories require prodigious total average rf power. In this age of energy conservation, this puts a high priority on high efficiency for the rf sources. Both modulating anodes and depressed collectors are being investigated in the quest for high efficiency at varying output powers

  8. Development of cold source moderator structure

    International Nuclear Information System (INIS)

    Aso, Tomokaze; Ishikura, Syuichi; Terada, Atsuhiko; Teshigawara, Makoto; Watanabe, Noboru; HIno, Ryutaro

    1999-01-01

    The cold and thermal neutrons generated at the target (which works as a spallation neutron source under a 5MW proton beam condition) is filtered with cold source moderators using supercritical hydrogen. Preliminary structural analysis was carried out to clarify technical problems on the concept of the thin-walled structure for the cold source moderator. Structural analytical results showed that the maximum stress of 1 12MPa occurred on the moderator surface, which exceeded the allowable design stresses of ordinary aluminum alloys. Flow patterns measured by water flow experiments agreed well with hydraulic analytical results, which showed that an impinging jet flow from an inner pipe of the moderator caused a recirculation flow on a large scale. Based on analytical and experimental results, new moderator structures with minute frames, blowing flow holes etc. were proposed to keep its strength and to suppress the recirculation flow. (author)

  9. Developments of ECR Sources and Associated Equipment

    International Nuclear Information System (INIS)

    Bieth, C.; Kantas, S.; Sortais, P.

    2002-01-01

    PANTECHNIK s.a. has improved and created ECR using room temperature coils, superconducting coils at 30K or permanent magnets ECR. Some of these sources are devoted to particular applications: ion implantation, nuclear and atomic physic, Proton and Hadrontherapy, radioactive beam. Stability and reproducibility have been particularly 1.0 Operational Improvements 1.1 High charge state for nuclear physics, atomic physic and RIB beam The HYPERNANOGAN [1] source (fig1) has been modified to run at 18GHz, and improved at 14.5GHz. The XENON spectrum (fig2) at 14.5GHz shows a Beam current of 3 μAe; for the charge state 30 + . At 18 GHz, the preliminary results indicate an improvement of 18% for Ar 8+ and 50% on Ar 9+ . In the atomic physics field our sources have been used to study the effect of extremely charged ions on a semiconductor surface ( Coulomb explosion)

  10. Developing Open Source System Expertise in Europe

    DEFF Research Database (Denmark)

    Nyborg, Mads; Gustafsson, Finn; Christensen, Jørgen Erik

    2011-01-01

    programme (IP). The aim of this IP is to exchange knowledge of and experience in local methods and techniques in the field of open source software knowledge in ICT by engaging a group of international students and lecturers in a joint, explorative investigation of contemporary methods of open...... are interested in knowing which factors play a role in information systems and what the similarities and differences between the various national approaches in open source software systems and techniques are. The event forms a unique opportunity in promoting active learning in an international environment...... source software systems. In addition the program focuses on the students learning interpersonal skills, such as personal and professional skills, multidisciplinary teamwork, communication, communication in a foreign language and leadership. The target group consists of European engineering students who...

  11. Developing a Successful Open Source Training Model

    Directory of Open Access Journals (Sweden)

    Belinda Lopez

    2010-01-01

    Full Text Available Training programs for open source software provide a tangible, and sellable, product. A successful training program not only builds revenue, it also adds to the overall body of knowledge available for the open source project. By gathering best practices and taking advantage of the collective expertise within a community, it may be possible for a business to partner with an open source project to build a curriculum that promotes the project and supports the needs of the company's training customers. This article describes the initial approach used by Canonical, the commercial sponsor of the Ubuntu Linux operating system, to engage the community in the creation of its training offerings. We then discuss alternate curriculum creation models and some of the conditions that are necessary for successful collaboration between creators of existing documentation and commercial training providers.

  12. Heavy ion source development at the Bevatron

    International Nuclear Information System (INIS)

    Richter, R.M.; Zajec, E.

    1975-10-01

    The Bevatron 20 MeV duoplasmatron source is currently being modified with the goal of producing 1 mA of 20 Neon 3+ . Initial tests at 420 keV show a total beam of 20 mA of which 400 μA is 20 Neon 3+ . The quantity of beam in various charge states is determined with a pulse field magnetic spectrometer. Titanium sublimation and cryogenic pumping of the PIG source in the High Voltage Terminal and its resultant effects on the acceleration of carbon and nitrogen are discussed

  13. A source term estimation method for a nuclear accident using atmospheric dispersion models

    DEFF Research Database (Denmark)

    Kim, Minsik; Ohba, Ryohji; Oura, Masamichi

    2015-01-01

    The objective of this study is to develop an operational source term estimation (STE) method applicable for a nuclear accident like the incident that occurred at the Fukushima Dai-ichi nuclear power station in 2011. The new STE method presented here is based on data from atmospheric dispersion...... models and short-range observational data around the nuclear power plants.The accuracy of this method is validated with data from a wind tunnel study that involved a tracer gas release from a scaled model experiment at Tokai Daini nuclear power station in Japan. We then use the methodology developed...... and validated through the effort described in this manuscript to estimate the release rate of radioactive material from the Fukushima Dai-ichi nuclear power station....

  14. Relation between source term and emergency planning for nuclear power plants

    International Nuclear Information System (INIS)

    Shi Zhongqi; Yang Ling

    1992-01-01

    Some background information of the severe accidents and source terms related to the nuclear power plant emergency planning are presented. The new source term information in NUREG-0956 and NUREG-1150, and possible changes in emergency planning requirements in U.S.A. are briefly provided. It is suggested that a principle is used in selecting source terms for establishing the emergency planning policy and a method is used in determining the Emergency Planning Zone (EPZ) size in China. Based on the research results of (1) EPZ size of PWR nuclear power plants being built in China, and (2) impact of reactor size and selected source terms on the EPZ size, it is concluded that the suggested principle and the method are suitable and feasible for PWR nuclear power plants in China

  15. Consideration of emergency source terms for pebble-bed high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Tao, Liu; Jun, Zhao; Jiejuan, Tong; Jianzhu, Cao

    2009-01-01

    Being the last barrier in the nuclear power plant defense-in-depth strategy, emergency planning (EP) is an integrated project. One of the key elements in this process is emergency source terms selection. Emergency Source terms for light water reactor (LWR) nuclear power plant (NPP) have been introduced in many technical documents, and advanced NPP emergency planning is attracting attention recently. Commercial practices of advanced NPP are undergoing in the world, pebble-bed high-temperature gas-cooled reactor (HTGR) power plant is under construction in China which is considered as a representative of advanced NPP. The paper tries to find some pieces of suggestion from our investigation. The discussion of advanced NPP EP will be summarized first, and then the characteristics of pebble-bed HTGR relating to EP will be described. Finally, PSA insights on emergency source terms selection and current pebble-bed HTGR emergency source terms suggestions are proposed

  16. Source terms: an investigation of uncertainties, magnitudes, and recommendations for research. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Levine, S.; Kaiser, G. D.; Arcieri, W. C.; Firstenberg, H.; Fulford, P. J.; Lam, P. S.; Ritzman, R. L.; Schmidt, E. R.

    1982-03-01

    The purpose of this document is to assess the state of knowledge and expert opinions that exist about fission product source terms from potential nuclear power plant accidents. This is so that recommendations can be made for research and analyses which have the potential to reduce the uncertainties in these estimated source terms and to derive improved methods for predicting their magnitudes. The main reasons for writing this report are to indicate the major uncertainties involved in defining realistic source terms that could arise from severe reactor accidents, to determine which factors would have the most significant impact on public risks and emergency planning, and to suggest research and analyses that could result in the reduction of these uncertainties. Source terms used in the conventional consequence calculations in the licensing process are not explicitly addressed.

  17. Selected source term topics. Report to CSNI by an OECD/NEA Group of experts

    International Nuclear Information System (INIS)

    1987-04-01

    CSNI Report 136 summarizes the results of the work performed by the Group of Experts on the Source Term and Environmental Consequences (PWG4) during the period extending from 1983 and 1986. This report is complementary to Part 1, 'Technical Status of the Source Term' of CSNI Report 135, 'Report to CSNI on Source Term Assessment, Containment atmosphere control systems, and accident consequences'; it considers in detail a number of very specific issues thought to be important in the source term area. It consists of: an executive summary (prepared by the Chairman of the Group), a section on conclusions and recommendations, and five technical chapters (fission product chemistry in the primary circuit of a LWR during severe accidents; resuspension/re-entrainment of aerosols in LWRs following a meltdown accident; iodine chemistry under severe accident conditions; effects of combustion, steam explosions and pressurized melt ejection on fission product behaviour; radionuclide removal by pool scrubbing), a technical annex and two appendices

  18. Diagnosis and prognosis of the source term by the French Safety Institut during an emergency on a PWR

    International Nuclear Information System (INIS)

    Chauliac, C.; Janot, L.; Jouzier, A.; Rague, B.

    1992-01-01

    The French approach for the diagnosis and the prognosis of the source term during an accident on a PWR is presented and the tools which have been developed to implement this approach at the Institute for Nuclear Protection and Safety (IPSN) are described. (author). 2 refs, 3 figs

  19. Technical basis for selecting radionuclide concentrations for use in Hanford tank basis for interim operation source term

    International Nuclear Information System (INIS)

    Cowley, W.L.

    1997-01-01

    This paper describes the development of a radiological source term for waste tanks at the Hanford Site Nuclear Reservation. It describes the methodology used to identify the most important radionuclides, determine appropriate concentrations, and define unit liter doses. An example of how unit liter doses are used is given

  20. Development of versatile multiaperture negative ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Cavenago, M.; Minarello, A.; Sattin, M. [INFN-LNL, v.le dell' Universita n 2, I-35020, Legnaro (PD) Italy (Italy); Serianni, G.; Antoni, V.; Bigi, M.; Pasqualotto, R.; Recchia, M.; Veltri, P.; Agostinetti, P.; Barbisan, M.; Baseggio, L.; Cervaro, V.; Degli Agostini, F.; Franchin, L.; Laterza, B.; Ravarotto, D.; Rossetto, F.; Zaniol, B.; Zucchetti, S. [Consorzio RFX, Associazione Euratom-ENEA sulla fusione, c.so S. Uniti 4, 35127 Padova (Italy); and others

    2015-04-08

    Enhancement of negative ion sources for production of large ion beams is a very active research field nowadays, driven from demand of plasma heating in nuclear fusion devices and accelerator applications. As a versatile test bench, the ion source NIO1 (Negative Ion Optimization 1) is being commissioned by Consorzio RFX and INFN. The nominal beam current of 135 mA at −60 kV is divided into 9 beamlets, with multiaperture extraction electrodes. The plasma is sustained by a 2 MHz radiofrequency power supply, with a standard matching box. A High Voltage Deck (HVD) placed inside the lead shielding surrounding NIO1 contains the radiofrequency generator, the gas control, electronics and power supplies for the ion source. An autonomous closed circuit water cooling system was installed for the whole system, with a branch towards the HVD, using carefully optimized helical tubing. Insulation transformer is installed in a nearby box. Tests of several magnetic configurations can be performed. Status of experiments, measured spectra and plasma luminosity are described. Upgrades of magnetic filter, beam calorimeter and extraction grid and related theoretical issues are reviewed.

  1. The long-term relationships among China's energy consumption sources and adjustments to its renewable energy policy

    International Nuclear Information System (INIS)

    Zou Gaolu

    2012-01-01

    To reduce its consumption of coal and oil in its primary energy consumption, China promotes the development of renewable energy resources. I have analysed the long-term relationship among China's primary energy consumption sources. Changes in coal consumption lead those in the consumption of other energy sources in the long term. Coal and oil fuels substitute for each other equally. The long-term elasticities of China's coal consumption relative to its hydroelectricity consumption were greater than one and nearly equal during the two sample periods. Therefore, increased hydroelectricity consumption did not imply a reduction in coal consumption. China holds abundant hydroelectricity, wind and, solar energy potential. China must prevent an excessive escalation of its economy and resultant energy demand to realise a meaningful substitution of coal with hydroelectricity. Moreover, China must develop and use wind and solar energy sources. Natural gas can be a good substitute for coal, given its moderate price growth and affordable price levels. - Highlights: ► Coal consumption changes lead those of other energy sources in the long term. ► Coal and oil fuels substitute for each other equally. ► Increased hydroelectricity consumption has not meant lower coal consumption. ► Wind, solar and natural gas are China's promising energy sources.

  2. Long term leaching of chlorinated solvents from source zones in low permeability settings with fractures

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup; Chambon, Julie Claire Claudia; Troldborg, Mads

    2008-01-01

    spreads to the low permeability matrix by diffusion. This results in a long term source of contamination due to back-diffusion. Leaching from such sources is further complicated by microbial degradation under anaerobic conditions to sequentially form the daughter products trichloroethylene, cis...

  3. Backup Sourcing Decisions for Coping with Supply Disruptions under Long-Term Horizons

    Directory of Open Access Journals (Sweden)

    Jing Hou

    2016-01-01

    Full Text Available This paper studies a buyer’s inventory control problem under a long-term horizon. The buyer has one major supplier that is prone to disruption risks and one backup supplier with higher wholesale price. Two kinds of sourcing methods are available for the buyer: single sourcing with/without contingent supply and dual sourcing. In contingent sourcing, the backup supplier is capacitated and/or has yield uncertainty, whereas in dual sourcing the backup supplier has an incentive to offer output flexibility during disrupted periods. The buyer’s expected cost functions and the optimal base-stock levels using each sourcing method under long-term horizon are obtained, respectively. The effects of three risk parameters, disruption probability, contingent capacity or uncertainty, and backup flexibility, are examined using comparative studies and numerical computations. Four sourcing methods, namely, single sourcing with contingent supply, dual sourcing, and single sourcing from either of the two suppliers, are also compared. These findings can be used as a valuable guideline for companies to select an appropriate sourcing strategy under supply disruption risks.

  4. Management of financial sources for innovative development: foreign countries experience

    Directory of Open Access Journals (Sweden)

    Dyba O. M.

    2016-12-01

    Full Text Available Authors have analyzed and synthesized the main features of financial sources management for innovative development in development economies of foreign countries. The article describes the peculiarities of above mentioned type of management, using the examples of such countries as Germany, USA and Japan, which represent different kinds of economy and society. The main sources for innovative development financing are highlighted within the national economies conditions. The authors proposed the generalized models of financial sources management for innovative development. The information will be useful for Ukrainian model of financial sources management development.

  5. Development and characterization of electron sources for diffraction applications

    Energy Technology Data Exchange (ETDEWEB)

    Casandruc, Albert

    2015-12-15

    The dream to control chemical reactions that are essential to life is now closer than ever to gratify. Recent scientific progress has made it possible to investigate phenomena and processes which deploy at the angstroms scale and at rates on the order femtoseconds. Techniques such as Ultrafast Electron Diffraction (UED) are currently able to reveal the spatial atomic configuration of systems with unit cell sizes on the order of a few nanometers with about 100 femtosecond temporal resolution. Still, major advances are needed for structural interrogation of biological systems like protein crystals, which have unit cell sizes of 10 nanometers or larger, and sample sizes of less than one micrometer. For such samples, the performance of these electron-based techniques is now limited by the quality, in particular the brightness, of the electron source. The current Ph.D. work represents a contribution towards the development and the characterization of electron sources which are essential to static and time-resolved electron diffraction techniques. The focus was on electron source fabrication and electron beam characterization measurements, using the solenoid and the aperture scan techniques, but also on the development and maintenance of the relevant experimental setups. As a result, new experimental facilities are now available in the group and, at the same time, novel concepts for generating electron beams for electron diffraction applications have been developed. In terms of existing electron sources, the capability to trigger and detect field emission from single double-gated field emitter Mo tips was successfully proven. These sharp emitter tips promise high brightness electron beams, but for investigating individual such structures, new engineering was needed. Secondly, the influence of the surface electric field on electron beam properties has been systematically performed for flat Mo photocathodes. This study is very valuable especially for state

  6. Development and characterization of electron sources for diffraction applications

    International Nuclear Information System (INIS)

    Casandruc, Albert

    2015-12-01

    The dream to control chemical reactions that are essential to life is now closer than ever to gratify. Recent scientific progress has made it possible to investigate phenomena and processes which deploy at the angstroms scale and at rates on the order femtoseconds. Techniques such as Ultrafast Electron Diffraction (UED) are currently able to reveal the spatial atomic configuration of systems with unit cell sizes on the order of a few nanometers with about 100 femtosecond temporal resolution. Still, major advances are needed for structural interrogation of biological systems like protein crystals, which have unit cell sizes of 10 nanometers or larger, and sample sizes of less than one micrometer. For such samples, the performance of these electron-based techniques is now limited by the quality, in particular the brightness, of the electron source. The current Ph.D. work represents a contribution towards the development and the characterization of electron sources which are essential to static and time-resolved electron diffraction techniques. The focus was on electron source fabrication and electron beam characterization measurements, using the solenoid and the aperture scan techniques, but also on the development and maintenance of the relevant experimental setups. As a result, new experimental facilities are now available in the group and, at the same time, novel concepts for generating electron beams for electron diffraction applications have been developed. In terms of existing electron sources, the capability to trigger and detect field emission from single double-gated field emitter Mo tips was successfully proven. These sharp emitter tips promise high brightness electron beams, but for investigating individual such structures, new engineering was needed. Secondly, the influence of the surface electric field on electron beam properties has been systematically performed for flat Mo photocathodes. This study is very valuable especially for state

  7. Global prospects for nuclear power development in the long term

    International Nuclear Information System (INIS)

    Semenov, Boris A.

    1994-01-01

    Population growth, economic development and improvement of quality of life will lead to significant increase of electricity consumption worldwide with more rapid growth in developing and newly industrialised countries. At the same time, concerns for environmental protection and security of supply will call for the development of alternatives to fossil fuels for electricity generation. Sustain ability will be a major driving factor for the choice of electricity generation options and strategies. Costs, and macro-economic and social impacts, will also influence future strategies in the electricity sector. Since renewable sources require significant development efforts to reach competitiveness, nuclear power is the most likely non-fossil source to be deployed on a large scale for base load electricity generation. Nuclear power is already a proven technology providing a significant share of electricity supply worldwide. In several countries, including the Republic of Korea, nuclear generated electricity is a major contributor to secure and competitive electricity supply. Technological progress aiming towards enhancing safety as well as technical and economic performance of nuclear power plants will enlarge the potential market share of nuclear generated electricity. The purpose of the paper is to give an overview of the prospects for nuclear power development in the world in the medium and long term. For the short term, up to 2005, projections of nuclear power installed capacities are rather straightforward to establish. The Agency publishes such projections every years, based upon a review of nuclear programmes in Member States. For the medium term, up to 2015, two illustrative cases have been developed by the IAEA reflecting contrasted, but not extreme, assumptions on the different parameters influencing nuclear power deployment worldwide. The paper gives estimations of the installed nuclear capacity, and of the share of nuclear power in total electricity and energy

  8. A study on the safety of spent fuel management. Radioactive source term modelling

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Lee, Hoo Keun; Park, Keun Il; Hwoang, Jung Ki; Chung, Choong Hwan [Korea Atomic Energy Research Inst., Daeduk (Korea, Republic of)

    1992-02-01

    The types and probabilities of events which may occur during the process of reception, transfer and storage of spent fuels in an away-from-reactor (AFR) spent fuel storage facility were analyzed in order to calculate the amount of radioactive material released to operation area and atmosphere, and the basic model for predicting the radioactive source-term under normal and abnormal operations were developed. Also, oxidation and dissolution of U0{sub 2} pellet was investigated to estimate the amount of radioactive materials released from spent fuel and the release characteristics of radionuclides from defected spent fuel rods was analyzed. Basic information using FIRAC code to analyze the ventilation system during fire accident was prepared and FIRIN was detached from FIRAC modified to simulate the compartment fire by personal computer. (Author).

  9. Microbial characterization for the Source-Term Waste Test Program (STTP) at Los Alamos

    International Nuclear Information System (INIS)

    Leonard, P.A.; Strietelmeier, B.A.; Pansoy-Hjelvik, M.E.; Villarreal, R.

    1999-01-01

    The effects of microbial activity on the performance of the proposed underground nuclear waste repository, the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico are being studied at Los Alamos National Laboratory (LANL) as part of an ex situ large-scale experiment. Actual actinide-containing waste is being used to predict the effect of potential brine inundation in the repository in the distant future. The study conditions are meant to simulate what might exist should the underground repository be flooded hundreds of years after closure as a result of inadvertent drilling into brine pockets below the repository. The Department of Energy (DOE) selected LANL to conduct the Actinide Source-Term Waste Test Program (STTP) to confirm the predictive capability of computer models being developed at Sandia National Laboratory

  10. Microbial characterization for the Source-Term Waste Test Program (STTP) at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, P.A.; Strietelmeier, B.A.; Pansoy-Hjelvik, M.E.; Villarreal, R.

    1999-04-01

    The effects of microbial activity on the performance of the proposed underground nuclear waste repository, the Waste Isolation Pilot Plant (WIPP) at Carlsbad, New Mexico are being studied at Los Alamos National Laboratory (LANL) as part of an ex situ large-scale experiment. Actual actinide-containing waste is being used to predict the effect of potential brine inundation in the repository in the distant future. The study conditions are meant to simulate what might exist should the underground repository be flooded hundreds of years after closure as a result of inadvertent drilling into brine pockets below the repository. The Department of Energy (DOE) selected LANL to conduct the Actinide Source-Term Waste Test Program (STTP) to confirm the predictive capability of computer models being developed at Sandia National Laboratory.

  11. Operational techniques employed for the liquid sodium source term control loops

    International Nuclear Information System (INIS)

    Chulos, L.E.

    1976-01-01

    Four Source Term Control Loops (STCLs) have been designed, constructed, and placed into operation at the Hanford Engineering Development Laboratory (HEDL) as part of the Radioactivity Control Technology program. The data obtained are used to determine the corrosion and deposition of LMFBR materials, including corrosion product radionuclides, in a non-isothermal flowing sodium system. The paper discusses operation of the STCL Facilities and, in particular, the methods used for controlling the oxygen content of the liquid sodium. These methods include cold trapping techniques, hot trapping, seeding the cold traps with sodium oxide, and precipitating the oxygen in the cold trap in a controlled manner. Operational problems encountered with the STCL Facilities and the techniques for correcting these problems are also discussed

  12. DUSTMS-D: DISPOSAL UNIT SOURCE TERM - MULTIPLE SPECIES - DISTRIBUTED FAILURE DATA INPUT GUIDE.

    Energy Technology Data Exchange (ETDEWEB)

    SULLIVAN, T.M.

    2006-01-01

    Performance assessment of a low-level waste (LLW) disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). Many of these physical processes are influenced by the design of the disposal facility (e.g., how the engineered barriers control infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This has been done and the resulting models have been incorporated into the computer code DUST-MS (Disposal Unit Source Term-Multiple Species). The DUST-MS computer code is designed to model water flow, container degradation, release of contaminants from the wasteform to the contacting solution and transport through the subsurface media. Water flow through the facility over time is modeled using tabular input. Container degradation models include three types of failure rates: (a) instantaneous (all containers in a control volume fail at once), (b) uniformly distributed failures (containers fail at a linear rate between a specified starting and ending time), and (c) gaussian failure rates (containers fail at a rate determined by a mean failure time, standard deviation and gaussian distribution). Wasteform release models include four release mechanisms: (a) rinse with partitioning (inventory is released instantly upon container failure subject to equilibrium partitioning (sorption) with

  13. Selective application of revised source terms to operating nuclear power plants

    International Nuclear Information System (INIS)

    Moon, Joo Hyun; Song, Jae Hyuk; Lee, Young Wook; Ko, Hyun Seok; Kang, Chang Sun

    2001-01-01

    More than 30 years later since 1962 when TID-14844 was promulgated, there has been big change of the US NRC's regulatory position in using accident source terms for radiological assessment following a design basis accident (DBA). To replace the instantaneous source terms of TID-14844, the time-dependent source terms of NUREG-1465 was published in 1995. In the meantime, the radiological acceptance criteria for reactor site evaluation in 10 CFR Part 100 were also revised. In particular, the concept of total effective dose equivalent has been incorporated in accordance with the radiation protection standards set forth in revised 10 CFR Part 20. Subsequently, the publication of Regulatory Guide 1.183 and the revision of Standard Review Plan 15.0.1 followed in 2000, which provided the licensee of operating nuclear power reactor with the acceptable guidance of applying the revised source term. The guidance allowed the holder of an operating license issued prior to January 10, 1997 to voluntarily revise the accident source terms used in the radiological consequence analyses of DBA. Regarding to its type of application, there suggested full and selective applications, Whether it is full or selective, based upon the scope and nature of associated plant modifications being proposed, the actual application of the revised source terms to an operating plant is expected to give a large impact on its facility design basis. Considering scope and cost of the analyses required for licensing, selective application is seemed to be more appealing to an licensee of the operating plant rather than full application. In this paper, hence, the selective application methodology is reviewed and is actally applied to the assessment of offsite radiological consequence following a LOCA at Ulchin Unit 3 and 4, in order to identify and analyze the potential impacts due to application of revised source terms and to assess the considerations taken in each application prior to its actual

  14. Source term determination from subcritical multiplication measurements at Koral-1 reactor

    International Nuclear Information System (INIS)

    Blazquez, J.B.; Barrado, J.M.

    1978-01-01

    By using an AmBe neutron source two independent procedures have been settled for the zero-power experimental fast-reactor Coral-1 in order to measure the source term which appears in the point kinetical equations. In the first one, the source term is measured when the reactor is just critical with source by taking advantage of the wide range of the linear approach to critical for Coral-1. In the second one, the measurement is made in subcritical state by making use of the previous calibrated control rods. Several applications are also included such as the measurement of the detector dead time, the determinations of the reactivity of small samples and the shape of the neutron importance of the source. (author)

  15. EUV source development for high-volume chip manufacturing tools

    Science.gov (United States)

    Stamm, Uwe; Yoshioka, Masaki; Kleinschmidt, Jürgen; Ziener, Christian; Schriever, Guido; Schürmann, Max C.; Hergenhan, Guido; Borisov, Vladimir M.

    2007-03-01

    Xenon-fueled gas discharge produced plasma (DPP) sources were integrated into Micro Exposure Tools already in 2004. Operation of these tools in a research environment gave early learning for the development of EUV sources for Alpha and Beta-Tools. Further experiments with these sources were performed for basic understanding on EUV source technology and limits, especially the achievable power and reliability. The intermediate focus power of Alpha-Tool sources under development is measured to values above 10 W. Debris mitigation schemes were successfully integrated into the sources leading to reasonable collector mirror lifetimes with target of 10 billion pulses due to the effective debris flux reduction. Source collector mirrors, which withstand the radiation and temperature load of Xenon-fueled sources, have been developed in cooperation with MediaLario Technologies to support intermediate focus power well above 10 W. To fulfill the requirements for High Volume chip Manufacturing (HVM) applications, a new concept for HVM EUV sources with higher efficiency has been developed at XTREME technologies. The discharge produced plasma (DPP) source concept combines the use of rotating disk electrodes (RDE) with laser exited droplet targets. The source concept is called laser assisted droplet RDE source. The fuel of these sources has been selected to be Tin. The conversion efficiency achieved with the laser assisted droplet RDE source is 2-3x higher compared to Xenon. Very high pulse energies well above 200 mJ / 2π sr have been measured with first prototypes of the laser assisted droplet RDE source. If it is possible to maintain these high pulse energies at higher repetition rates a 10 kHz EUV source could deliver 2000 W / 2π sr. According to the first experimental data the new concept is expected to be scalable to an intermediate focus power on the 300 W level.

  16. Developer Network : Open Source Personal Digital Assistant ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Articles de revue. Handheld computers for survey and trial data collection in resource-poor settings : development and evaluation of PDACT, a Palm TM pilot interviewing system ... L'Initiative des conseils subventionnaires de la recherche scientifique en Afrique subsaharienne remporte le prix de la diplomatie scientifique.

  17. Developing seismogenic source models based on geologic fault data

    Science.gov (United States)

    Haller, Kathleen M.; Basili, Roberto

    2011-01-01

    Calculating seismic hazard usually requires input that includes seismicity associated with known faults, historical earthquake catalogs, geodesy, and models of ground shaking. This paper will address the input generally derived from geologic studies that augment the short historical catalog to predict ground shaking at time scales of tens, hundreds, or thousands of years (e.g., SSHAC 1997). A seismogenic source model, terminology we adopt here for a fault source model, includes explicit three-dimensional faults deemed capable of generating ground motions of engineering significance within a specified time frame of interest. In tectonically active regions of the world, such as near plate boundaries, multiple seismic cycles span a few hundred to a few thousand years. In contrast, in less active regions hundreds of kilometers from the nearest plate boundary, seismic cycles generally are thousands to tens of thousands of years long. Therefore, one should include sources having both longer recurrence intervals and possibly older times of most recent rupture in less active regions of the world rather than restricting the model to include only Holocene faults (i.e., those with evidence of large-magnitude earthquakes in the past 11,500 years) as is the practice in tectonically active regions with high deformation rates. During the past 15 years, our institutions independently developed databases to characterize seismogenic sources based on geologic data at a national scale. Our goal here is to compare the content of these two publicly available seismogenic source models compiled for the primary purpose of supporting seismic hazard calculations by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the U.S. Geological Survey (USGS); hereinafter we refer to the two seismogenic source models as INGV and USGS, respectively. This comparison is timely because new initiatives are emerging to characterize seismogenic sources at the continental scale (e.g., SHARE in the

  18. Review of radionuclide source terms used for performance-assessment analyses

    International Nuclear Information System (INIS)

    Barnard, R.W.

    1993-06-01

    Two aspects of the radionuclide source terms used for total-system performance assessment (TSPA) analyses have been reviewed. First, a detailed radionuclide inventory (i.e., one in which the reactor type, decay, and burnup are specified) is compared with the standard source-term inventory used in prior analyses. The latter assumes a fixed ratio of pressurized-water reactor (PWR) to boiling-water reactor (BWR) spent fuel, at specific amounts of burnup and at 10-year decay. TSPA analyses have been used to compare the simplified source term with the detailed one. The TSPA-91 analyses did not show a significant difference between the source terms. Second, the radionuclides used in source terms for TSPA aqueous-transport analyses have been reviewed to select ones that are representative of the entire inventory. It is recommended that two actinide decay chains be included (the 4n+2 ''uranium'' and 4n+3 ''actinium'' decay series), since these include several radionuclides that have potentially important release and dose characteristics. In addition, several fission products are recommended for the same reason. The choice of radionuclides should be influenced by other parameter assumptions, such as the solubility and retardation of the radionuclides

  19. Research and development in alternative energy sources

    International Nuclear Information System (INIS)

    Lamptey, J.; Moo-Young, M.; Sullivan, H.F.

    1990-01-01

    This paper comprehensively discusses the various bioconversion and thermochemical processes. It recommends that the most urgent research and development issues should relate to direct microbial conversion systems for starch and cellulosic material and to basic biomass combustion rates and mechanisms. An overview of some of the major renewable energy resources and conversion technologies along with the potentials and problems associated with these are also presented.(author). 235 refs., 2 tabs

  20. Legislation framework for Croatian renewable energy sources development

    Directory of Open Access Journals (Sweden)

    Raguzin Igor

    2007-01-01

    Full Text Available The energy sector reform in the Republic of Croatia (started 2001, which comprises restructuring, liberalization, privatization, and changes in the overall energy sector, has a significant effect on the possibilities of introducing and increasing the share of renewable energy sources (RES. The adoption of a new legislative framework within the context of reforming Croatia’s energy sector is of key importance for further development and for the future or RES utilization. The Electricity Market Act sets out the le- gal obligation to purchase electricity produced from RES in the manner that a quota or a minimum obligatory share of RES in electricity production is determined by a Government ordinance combined with Tariff system for the production of electricity from renewable energy sources and co-generation. Consequently, on the one hand, incentive funds needed to cover increased costs of production from RES will be collected from customers through the supplier and distributed to privileged producers (feed-in-tariffs, purchase is guaranteed to RES producers on known terms through the Market Opera- tor. On the other hand, RES investment projects will be encouraged by pur- pose-specific government subsidy and by the Environmental Protection and Energy Efficiency Fund (out of public budget. By applying new energy legislation and associated by-laws (coming into force in 2007, RES projects in Croatia will be provided with a complete and stable legal framework as well as support through incentive measures which will equitably value environmental, social and other benefits of RES use.

  1. Parameterizing unresolved obstacles with source terms in wave modeling: A real-world application

    Science.gov (United States)

    Mentaschi, Lorenzo; Kakoulaki, Georgia; Vousdoukas, Michalis; Voukouvalas, Evangelos; Feyen, Luc; Besio, Giovanni

    2018-06-01

    Parameterizing the dissipative effects of small, unresolved coastal features, is fundamental to improve the skills of wave models. The established technique to deal with this problem consists in reducing the amount of energy advected within the propagation scheme, and is currently available only for regular grids. To find a more general approach, Mentaschi et al., 2015b formulated a technique based on source terms, and validated it on synthetic case studies. This technique separates the parameterization of the unresolved features from the energy advection, and can therefore be applied to any numerical scheme and to any type of mesh. Here we developed an open-source library for the estimation of the transparency coefficients needed by this approach, from bathymetric data and for any type of mesh. The spectral wave model WAVEWATCH III was used to show that in a real-world domain, such as the Caribbean Sea, the proposed approach has skills comparable and sometimes better than the established propagation-based technique.

  2. Toward a Mechanistic Source Term in Advanced Reactors: Characterization of Radionuclide Transport and Retention in a Sodium Cooled Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Brunett, Acacia J.; Bucknor, Matthew; Grabaskas, David

    2016-04-17

    A vital component of the U.S. reactor licensing process is an integrated safety analysis in which a source term representing the release of radionuclides during normal operation and accident sequences is analyzed. Historically, source term analyses have utilized bounding, deterministic assumptions regarding radionuclide release. However, advancements in technical capabilities and the knowledge state have enabled the development of more realistic and best-estimate retention and release models such that a mechanistic source term assessment can be expected to be a required component of future licensing of advanced reactors. Recently, as part of a Regulatory Technology Development Plan effort for sodium cooled fast reactors (SFRs), Argonne National Laboratory has investigated the current state of knowledge of potential source terms in an SFR via an extensive review of previous domestic experiments, accidents, and operation. As part of this work, the significant sources and transport processes of radionuclides in an SFR have been identified and characterized. This effort examines all stages of release and source term evolution, beginning with release from the fuel pin and ending with retention in containment. Radionuclide sources considered in this effort include releases originating both in-vessel (e.g. in-core fuel, primary sodium, cover gas cleanup system, etc.) and ex-vessel (e.g. spent fuel storage, handling, and movement). Releases resulting from a primary sodium fire are also considered as a potential source. For each release group, dominant transport phenomena are identified and qualitatively discussed. The key product of this effort was the development of concise, inclusive diagrams that illustrate the release and retention mechanisms at a high level, where unique schematics have been developed for in-vessel, ex-vessel and sodium fire releases. This review effort has also found that despite the substantial range of phenomena affecting radionuclide release, the

  3. ITER safety task NID-5a: ITER tritium environmental source terms - safety analysis basis

    International Nuclear Information System (INIS)

    Natalizio, A.; Kalyanam, K.M.

    1994-09-01

    The Canadian Fusion Fuels Technology Project's (CFFTP) is part of the contribution to ITER task NID-5a, Initial Tritium Source Term. This safety analysis basis constitutes the first part of the work for establishing tritium source terms and is intended to solicit comments and obtain agreement. The analysis objective is to provide an early estimate of tritium environmental source terms for the events to be analyzed. Events that would result in the loss of tritium are: a Loss of Coolant Accident (LOCA), a vacuum vessel boundary breach. a torus exhaust line failure, a fuelling machine process boundary failure, a fuel processing system process boundary failure, a water detritiation system process boundary failure and an isotope separation system process boundary failure. 9 figs

  4. Advanced Reactor PSA Methodologies for System Reliability Analysis and Source Term Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, D.; Brunett, A.; Passerini, S.; Grelle, A.; Bucknor, M.

    2017-06-26

    Beginning in 2015, a project was initiated to update and modernize the probabilistic safety assessment (PSA) of the GE-Hitachi PRISM sodium fast reactor. This project is a collaboration between GE-Hitachi and Argonne National Laboratory (Argonne), and funded in part by the U.S. Department of Energy. Specifically, the role of Argonne is to assess the reliability of passive safety systems, complete a mechanistic source term calculation, and provide component reliability estimates. The assessment of passive system reliability focused on the performance of the Reactor Vessel Auxiliary Cooling System (RVACS) and the inherent reactivity feedback mechanisms of the metal fuel core. The mechanistic source term assessment attempted to provide a sequence specific source term evaluation to quantify offsite consequences. Lastly, the reliability assessment focused on components specific to the sodium fast reactor, including electromagnetic pumps, intermediate heat exchangers, the steam generator, and sodium valves and piping.

  5. Independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool

    International Nuclear Information System (INIS)

    Madni, I.K.; Eltawila, F.

    1994-01-01

    MELCOR is a fully integrated computer code that models all phases of the progression of severe accidents in light water reactor nuclear power plants, and is being developed for the US Nuclear Regulatory Commission (NRC) by Sandia National Laboratories (SNL). Brookhaven National Laboratory (BNL) has a program with the NRC called ''MELCOR Verification, Benchmarking, and Applications,'' whose aim is to provide independent assessment of MELCOR as a severe accident thermal-hydraulic/source term analysis tool. The scope of this program is to perform quality control verification on all released versions of MELCOR, to benchmark MELCOR against more mechanistic codes and experimental data from severe fuel damage tests, and to evaluate the ability of MELCOR to simulate long-term severe accident transients in commercial LWRs, by applying the code to model both BWRs and PWRs. Under this program, BNL provided input to the NRC-sponsored MELCOR Peer Review, and is currently contributing to the MELCOR Cooperative Assessment Program (MCAP). This paper presents a summary of MELCOR assessment efforts at BNL and their contribution to NRC goals with respect to MELCOR

  6. Development of 63Ni sources for defence related applications

    International Nuclear Information System (INIS)

    Udhayakumar, J.; Pardeshi, G.S.; Gandhi, Shyamala S.; Dash, A.; Venkatesh, Meera

    2004-01-01

    63 Ni is seen as a good substitute for the conventional sources of ionization used in electron capture detectors in Gas Chromatography applications. It has advantages such as source stability, reasonably long shelf life due to its long half-life and viable for safe and easy handling due to low energy beta emission. At the special request from the Defence Establishments in India for supply of 63 Ni beta source on special dimension of a curved inner copper ring area, the new electro-deposition cell was designed and used for routine preparation and supply of such sources. The paper describes the procedure for fabrication of 63 Ni beta sources by electro-deposition method. Activity up to ∼370 MBq (∼10 mCi) was electrodeposited exclusively on inner curved area of ∼4 sq.cm. Copper annular ring, using Boric acid electrolyte bath solution at a temperature range of 50 deg - 60 deg C with a current density of ∼ 6 ma/sq.cm. For this purpose, a new electro depositing cell was specially designed and used. The paper discusses the details regarding source requirement, source preparation parameters, film thickness and its impact on beta output, source quality control aspects and other applications of the sources. The paper also highlights the demand and supply scenario of such electrodeposited sources, in terms of commercial supply sale value, as an import substitute. (author)

  7. The European source term code ESTER - basic ideas and tools for coupling of ATHLET and ESTER

    International Nuclear Information System (INIS)

    Schmidt, F.; Schuch, A.; Hinkelmann, M.

    1993-04-01

    The French software house CISI and IKE of the University of Stuttgart have developed during 1990 and 1991 in the frame of the Shared Cost Action Reactor Safety the informatic structure of the European Source TERm Evaluation System (ESTER). Due to this work tools became available which allow to unify on an European basis both code development and code application in the area of severe core accident research. The behaviour of reactor cores is determined by thermal hydraulic conditions. Therefore for the development of ESTER it was important to investigate how to integrate thermal hydraulic code systems with ESTER applications. This report describes the basic ideas of ESTER and improvements of ESTER tools in view of a possible coupling of the thermal hydraulic code system ATHLET and ESTER. Due to the work performed during this project the ESTER tools became the most modern informatic tools presently available in the area of severe accident research. A sample application is given which demonstrates the use of the new tools. (orig.) [de

  8. Development of a compact powdery sample negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Wada, Motoi [Doshisha Univ., Tanabe, Kyoto (Japan). Faculty of Engineering; Sasao, Mamiko; Kawano, Hiroyuki

    1997-02-01

    A gas-feed-free compact negative ion source can be realized by utilizing the process of electron stimulated desorption from powdery sample. A negative ion source of this type is designed to be attached to a standard 1.33 inch copper-gasket-flange. The ion source is operated stable with LiH powder for more than 10 hours with the mass-separated negative hydrogen ion current of 1 nA. The source causes minute gas emission, and particularly suitable for ion beam applications in which a good vacuum is required. The present status of the compact ion source development is briefly described. (author)

  9. Developing an Open Source Option for NASA Software

    Science.gov (United States)

    Moran, Patrick J.; Parks, John W. (Technical Monitor)

    2003-01-01

    We present arguments in favor of developing an Open Source option for NASA software; in particular we discuss how Open Source is compatible with NASA's mission. We compare and contrast several of the leading Open Source licenses, and propose one - the Mozilla license - for use by NASA. We also address some of the related issues for NASA with respect to Open Source. In particular, we discuss some of the elements in the External Release of NASA Software document (NPG 2210.1A) that will likely have to be changed in order to make Open Source a reality withm the agency.

  10. Use of source term code package in the ELEBRA MX-850 system

    International Nuclear Information System (INIS)

    Guimaraes, A.C.F.; Goes, A.G.A.

    1988-12-01

    The implantation of source term code package in the ELEBRA-MX850 system is presented. The source term is formed when radioactive materials generated in nuclear fuel leakage toward containment and the external environment to reactor containment. The implantated version in the ELEBRA system are composed of five codes: MARCH 3, TRAPMELT 3, THCCA, VANESA and NAVA. The original example case was used. The example consists of a small loca accident in a PWR type reactor. A sensitivity study for the TRAPMELT 3 code was carried out, modifying the 'TIME STEP' to estimate the processing time of CPU for executing the original example case. (M.C.K.) [pt

  11. Source term estimation based on in-situ gamma spectrometry using a high purity germanium detector

    International Nuclear Information System (INIS)

    Pauly, J.; Rojas-Palma, C.; Sohier, A.

    1997-06-01

    An alternative method to reconstruct the source term of a nuclear accident is proposed. The technique discussed here involves the use of in-situ gamma spectrometry. The validation of the applied methodology has been possible through the monitoring of routine releases of Ar-41 originating at a Belgian site from an air cooled graphite research reactor. This technique provides a quick nuclide specific decomposition of the source term and therefore will be have an enormous potential if implemented in nuclear emergency preparedness and radiological assessments of nuclear accidents during the early phase

  12. Source-term characterisation and solid speciation of plutonium at the Semipalatinsk NTS, Kazakhstan.

    Science.gov (United States)

    Nápoles, H Jiménez; León Vintró, L; Mitchell, P I; Omarova, A; Burkitbayev, M; Priest, N D; Artemyev, O; Lukashenko, S

    2004-01-01

    New data on the concentrations of key fission/activation products and transuranium nuclides in samples of soil and water from the Semipalatinsk Nuclear Test Site are presented and interpreted. Sampling was carried out at Ground Zero, Lake Balapan, the Tel'kem craters and reference locations within the test site boundary well removed from localised sources. Radionuclide ratios have been used to characterise the source term(s) at each of these sites. The geochemical partitioning of plutonium has also been examined and it is shown that the bulk of the plutonium contamination at most of the sites examined is in a highly refractory, non-labile form.

  13. Source-term characterisation and solid speciation of plutonium at the Semipalatinsk NTS, Kazakhstan

    Energy Technology Data Exchange (ETDEWEB)

    Napoles, H.J.H. Jimenez; Leon Vintro, L. E-mail: luis.leon@ucd.ie; Mitchell, P.I.; Omarova, A.; Burkitbayev, M.; Priest, N.D.; Artemyev, O.; Lukashenko, S

    2004-09-01

    New data on the concentrations of key fission/activation products and transuranium nuclides in samples of soil and water from the Semipalatinsk Nuclear Test Site are presented and interpreted. Sampling was carried out at Ground Zero, Lake Balapan, the Tel'kem craters and reference locations within the test site boundary well removed from localised sources. Radionuclide ratios have been used to characterise the source term(s) at each of these sites. The geochemical partitioning of plutonium has also been examined and it is shown that the bulk of the plutonium contamination at most of the sites examined is in a highly refractory, non-labile form.

  14. The long-term problems of contaminated land: Sources, impacts and countermeasures

    Energy Technology Data Exchange (ETDEWEB)

    Baes, C.F. III

    1986-11-01

    This report examines the various sources of radiological land contamination; its extent; its impacts on man, agriculture, and the environment; countermeasures for mitigating exposures; radiological standards; alternatives for achieving land decontamination and cleanup; and possible alternatives for utilizing the land. The major potential sources of extensive long-term land contamination with radionuclides, in order of decreasing extent, are nuclear war, detonation of a single nuclear weapon (e.g., a terrorist act), serious reactor accidents, and nonfission nuclear weapons accidents that disperse the nuclear fuels (termed ''broken arrows'').

  15. The long-term problems of contaminated land: Sources, impacts and countermeasures

    International Nuclear Information System (INIS)

    Baes, C.F. III.

    1986-11-01

    This report examines the various sources of radiological land contamination; its extent; its impacts on man, agriculture, and the environment; countermeasures for mitigating exposures; radiological standards; alternatives for achieving land decontamination and cleanup; and possible alternatives for utilizing the land. The major potential sources of extensive long-term land contamination with radionuclides, in order of decreasing extent, are nuclear war, detonation of a single nuclear weapon (e.g., a terrorist act), serious reactor accidents, and nonfission nuclear weapons accidents that disperse the nuclear fuels (termed ''broken arrows'')

  16. Design parameters and source terms: Volume 1, Design parameters: Revision 0

    International Nuclear Information System (INIS)

    1987-10-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report by Stearns Catalytic Corporation (SCC), entitled ''Design Parameters and Source Terms for a Two-Phase Repository in Salt,'' 1985, to the level of the Site Characterization Plan - Conceptual Design Report. The previous unpublished SCC Study identifies the data needs for the Environmental Assessment effort for seven possible Salt Repository sites

  17. Epistemic Communities, Situated Learning and Open Source Software Development

    DEFF Research Database (Denmark)

    Edwards, Kasper

    2001-01-01

    This paper analyses open source software (OSS) development as an epistemic community where each individual project is perceived as a single epistemic community. OSS development is a learning process where the involved parties contribute to, and learn from the community. It is discovered that theory...... of epistemic communities does indeed contribute to the understanding of open source software development. But, the important learning process of open source software development is not readily explained. The paper then introduces situated learning and legitimate peripheral participation as theoretical...

  18. Variational Iterative Refinement Source Term Estimation Algorithm Assessment for Rural and Urban Environments

    Science.gov (United States)

    Delle Monache, L.; Rodriguez, L. M.; Meech, S.; Hahn, D.; Betancourt, T.; Steinhoff, D.

    2016-12-01

    It is necessary to accurately estimate the initial source characteristics in the event of an accidental or intentional release of a Chemical, Biological, Radiological, or Nuclear (CBRN) agent into the atmosphere. The accurate estimation of the source characteristics are important because many times they are unknown and the Atmospheric Transport and Dispersion (AT&D) models rely heavily on these estimates to create hazard assessments. To correctly assess the source characteristics in an operational environment where time is critical, the National Center for Atmospheric Research (NCAR) has developed a Source Term Estimation (STE) method, known as the Variational Iterative Refinement STE algorithm (VIRSA). VIRSA consists of a combination of modeling systems. These systems include an AT&D model, its corresponding STE model, a Hybrid Lagrangian-Eulerian Plume Model (H-LEPM), and its mathematical adjoint model. In an operational scenario where we have information regarding the infrastructure of a city, the AT&D model used is the Urban Dispersion Model (UDM) and when using this model in VIRSA we refer to the system as uVIRSA. In all other scenarios where we do not have the city infrastructure information readily available, the AT&D model used is the Second-order Closure Integrated PUFF model (SCIPUFF) and the system is referred to as sVIRSA. VIRSA was originally developed using SCIPUFF 2.4 for the Defense Threat Reduction Agency and integrated into the Hazard Prediction and Assessment Capability and Joint Program for Information Systems Joint Effects Model. The results discussed here are the verification and validation of the upgraded system with SCIPUFF 3.0 and the newly implemented UDM capability. To verify uVIRSA and sVIRSA, synthetic concentration observation scenarios were created in urban and rural environments and the results of this verification are shown. Finally, we validate the STE performance of uVIRSA using scenarios from the Joint Urban 2003 (JU03

  19. Development of a cryogenic source of polarized deuterons ''Polaris''

    International Nuclear Information System (INIS)

    Anishchenko, N.G.; Belushkina, A.A.; Ershov, V.P.

    1985-01-01

    To obtain a beam of polarized deuterons, a cryogenic source ''Polaris'' has been developed according to the program of research at the Dubna synchrophasotron. The source is installed on a high-voltage terminal of the linac preaccelerator. A beam of deuterons from the source is accelerated in the synchrophasotron. At present the source is being improved. A polarimeter with 3 He and 4 He targets has been developed to measure the polarization of the beam of deuterons after the linac. Results of this work are presented in the report

  20. RENEWABLE ENERGY SOURCES IN POLAND - CONDITIONS AND POSSIBILITES OF DEVELOPMENT

    Energy Technology Data Exchange (ETDEWEB)

    Gawlik, L.; Mokrzycki, E.; Ney, R.

    2007-07-01

    The paper describes the state of the art in renewable energy sources development. The obligation resulting from the membership of Poland in the European Union as well as from other international agreements in the scope of renewable energy sources development are described. The production of electricity, heat and biofuels in Poland is given and the perspectives of development of particular renewable energy sources in Poland are discussed in the view of potential reserves and other constrains. The economic aspects of renewable energy technologies are shown. The environmental pros and cons of biomass energy development are described. Arguments for development of renewable energy sources use are stated: the decrease of dependence from primary energy sources, the decrease the emission of green house gases and the recovery of agricultural regions of the country. In conclusion it is stated that the significance of renewable energy sources in Polish conditions is constrained to local societies. Their development should be adjusted to conditions predominating in a given region and that wider consumption of renewable energy sources should develop in conformity with sustainable development, so it is necessary to reach agreement between local societies, institutions dealing with environment protection and representatives of power sector. (auth)

  1. Development of H- sources at Brookhaven National Laboratory

    International Nuclear Information System (INIS)

    Prelec, K.

    1977-01-01

    Negative hydrogen ion sources have been developed at Brookhaven National Laboratory for several years, with the initial goal to design a source for accelerator applications and later on to design a large unit for applications in neutral beam injectors of magnetic fusion devices. Three types of sources were investigated, a hollow discharge duoplasmatron yielding H - currents up to 60 mA, a Penning source yielding H - currents up to 440 mA, and a magnetron source yielding H - currents up to 1 A. All sources operate with a mixture of hydrogen gas and cesium vapors, and H - ions are most likely produced on cesium covered electrode surfaces. A larger model of a Penning/magnetron source was constructed and will be tested soon; it incorporates among other new features a system for the cooling of the cathode

  2. Using Reactive Transport Modeling to Evaluate the Source Term at Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Y. Chen

    2001-12-19

    The conventional approach of source-term evaluation for performance assessment of nuclear waste repositories uses speciation-solubility modeling tools and assumes pure phases of radioelements control their solubility. This assumption may not reflect reality, as most radioelements (except for U) may not form their own pure phases. As a result, solubility limits predicted using the conventional approach are several orders of magnitude higher then the concentrations of radioelements measured in spent fuel dissolution experiments. This paper presents the author's attempt of using a non-conventional approach to evaluate source term of radionuclide release for Yucca Mountain. Based on the general reactive-transport code AREST-CT, a model for spent fuel dissolution and secondary phase precipitation has been constructed. The model accounts for both equilibrium and kinetic reactions. Its predictions have been compared against laboratory experiments and natural analogues. It is found that without calibrations, the simulated results match laboratory and field observations very well in many aspects. More important is the fact that no contradictions between them have been found. This provides confidence in the predictive power of the model. Based on the concept of Np incorporated into uranyl minerals, the model not only predicts a lower Np source-term than that given by conventional Np solubility models, but also produces results which are consistent with laboratory measurements and observations. Moreover, two hypotheses, whether Np enters tertiary uranyl minerals or not, have been tested by comparing model predictions against laboratory observations, the results favor the former. It is concluded that this non-conventional approach of source term evaluation not only eliminates over-conservatism in conventional solubility approach to some extent, but also gives a realistic representation of the system of interest, which is a prerequisite for truly understanding the long-term

  3. Using Reactive Transport Modeling to Evaluate the Source Term at Yucca Mountain

    International Nuclear Information System (INIS)

    Y. Chen

    2001-01-01

    The conventional approach of source-term evaluation for performance assessment of nuclear waste repositories uses speciation-solubility modeling tools and assumes pure phases of radioelements control their solubility. This assumption may not reflect reality, as most radioelements (except for U) may not form their own pure phases. As a result, solubility limits predicted using the conventional approach are several orders of magnitude higher then the concentrations of radioelements measured in spent fuel dissolution experiments. This paper presents the author's attempt of using a non-conventional approach to evaluate source term of radionuclide release for Yucca Mountain. Based on the general reactive-transport code AREST-CT, a model for spent fuel dissolution and secondary phase precipitation has been constructed. The model accounts for both equilibrium and kinetic reactions. Its predictions have been compared against laboratory experiments and natural analogues. It is found that without calibrations, the simulated results match laboratory and field observations very well in many aspects. More important is the fact that no contradictions between them have been found. This provides confidence in the predictive power of the model. Based on the concept of Np incorporated into uranyl minerals, the model not only predicts a lower Np source-term than that given by conventional Np solubility models, but also produces results which are consistent with laboratory measurements and observations. Moreover, two hypotheses, whether Np enters tertiary uranyl minerals or not, have been tested by comparing model predictions against laboratory observations, the results favor the former. It is concluded that this non-conventional approach of source term evaluation not only eliminates over-conservatism in conventional solubility approach to some extent, but also gives a realistic representation of the system of interest, which is a prerequisite for truly understanding the long-term

  4. Development of a dc, broad beam, Mevva ion source

    International Nuclear Information System (INIS)

    Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; MacGill, R.A.

    1991-09-01

    We are developing an embodiment of metal vapor vacuum arc (Mevva) ion source which will operate dc and have very large area beam. In preliminary testing, a dc titanium ion beam was formed with a current of approximately 0.6 amperes at an extraction voltage of 9kV (about 18 keV ion energy, by virtue of the ion charge state distribution) and using an 18 cm diameter set of multi-aperture. Separately, we have tested and formed beam from a 50 cm diameter (2000 cm 2 ) set of grids using a pulsed plasma gun. This configuration appears to be very efficient in terms of plasma utilization, and we have formed beams with diameter 33 cm (FWHM) and ion current up to 7 amperes at an extraction voltage of 50 kV (about 100 keV mean ion energy) and up to 20 amperes peak at the current overshoot part of the beam pulse. Here we describe this Part Of our Mevva development program and summarize the results obtained to-date

  5. Development of the ion source for PDX neutral beam injection

    International Nuclear Information System (INIS)

    Menon, M.M.; Tsai, C.C.; Gardner, W.L.; Barber, G.C.; Haselton, H.H.; Ponte, N.S.; Ryan, P.M.; Schechter, D.E.; Stirling, W.L.; Whealton, J.H.

    1979-01-01

    The paper describes the development of the ion source for neutral beam injection heating of PDX plasma. After a brief description of the plasma generator, the performance characteristics of the source, with different types of grids, are described. Based on test stand results it is concluded that at least two different versions of the source should be able to meet and even exceed the neutral power and energy requirements expected out of PDX injectors

  6. Hydrologic Source Term Processes and Models for the Clearwater and Wineskin Tests, Rainier Mesa, Nevada National Security Site

    Energy Technology Data Exchange (ETDEWEB)

    Carle, Steven F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-05-04

    This report describes the development, processes, and results of a hydrologic source term (HST) model for the CLEARWATER (U12q) and WINESKIN (U12r) tests located on Rainier Mesa, Nevada National Security Site, Nevada (Figure 1.1). Of the 61 underground tests (involving 62 unique detonations) conducted on Rainier Mesa (Area 12) between 1957 and 1992 (USDOE, 2015), the CLEARWATER and WINESKIN tests present many unique features that warrant a separate HST modeling effort from other Rainier Mesa tests.

  7. Release of radionuclides following severe accident in interim storage facility. Source term determination

    International Nuclear Information System (INIS)

    Morandi, S.; Mariani, M.; Giacobbo, F.; Covini, R.

    2006-01-01

    Among the severe accidents that can cause the release of radionuclides from an interim storage facility, with a consequent relevant radiological impact on the population, there is the impact of an aircraft on the facility. In this work, a safety assessment analysis for the case of an aircraft crash into an interim storage facility is tackled. To this aim a methodology, based upon DOE, IAEA and NUREG standard procedures and upon conservative yet realistic hypothesis, has been developed in order to evaluate the total radioactivity, source term, released to the biosphere in consequence of the impact, without recurring to the use of complicated numerical codes. The procedure consists in the identification of the accidental scenarios, in the evaluation of the consequent damage to the building structures and to the waste packages and in the determination of the total release of radionuclides through the building-atmosphere interface. The methodology here developed has been applied to the case of an aircraft crash into an interim storage facility currently under design. Results show that in case of perforation followed by a fire incident the total released activity would be greater of some orders of magnitude with respect to the case of mere perforation. (author)

  8. Evaluation of Long-term Performance of Enhanced Anaerobic Source Zone Bioremediation using mass flux

    Science.gov (United States)

    Haluska, A.; Cho, J.; Hatzinger, P.; Annable, M. D.

    2017-12-01

    Chlorinated ethene DNAPL source zones in groundwater act as potential long term sources of contamination as they dissolve yielding concentrations well above MCLs, posing an on-going public health risk. Enhanced bioremediation has been applied to treat many source zones with significant promise, but long-term sustainability of this technology has not been thoroughly assessed. This study evaluated the long-term effectiveness of enhanced anaerobic source zone bioremediation at chloroethene contaminated sites to determine if the treatment prevented contaminant rebound and removed NAPL from the source zone. Long-term performance was evaluated based on achieving MCL-based contaminant mass fluxes in parent compound concentrations during different monitoring periods. Groundwater concertation versus time data was compiled for 6-sites and post-remedial contaminant mass flux data was then measured using passive flux meters at wells both within and down-gradient of the source zone. Post-remedial mass flux data was then combined with pre-remedial water quality data to estimate pre-remedial mass flux. This information was used to characterize a DNAPL dissolution source strength function, such as the Power Law Model and the Equilibrium Stream tube model. The six-sites characterized for this study were (1) Former Charleston Air Force Base, Charleston, SC; (2) Dover Air Force Base, Dover, DE; (3) Treasure Island Naval Station, San Francisco, CA; (4) Former Raritan Arsenal, Edison, NJ; (5) Naval Air Station, Jacksonville, FL; and, (6) Former Naval Air Station, Alameda, CA. Contaminant mass fluxes decreased for all the sites by the end of the post-treatment monitoring period and rebound was limited within the source zone. Post remedial source strength function estimates suggest that decreases in contaminant mass flux will continue to occur at these sites, but a mass flux based on MCL levels may never be exceeded. Thus, site clean-up goals should be evaluated as order

  9. Benchmarking the New RESRAD-OFFSITE Source Term Model with DUST-MS and GoldSim - 13377

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J.J.; Kamboj, S.; Gnanapragasam, E.; Yu, C. [Argonne National Laboratory, Argonne, IL 60439 (United States)

    2013-07-01

    RESRAD-OFFSITE is a computer code developed by Argonne National Laboratory under the sponsorship of U.S. Department of Energy (DOE) and U.S. Nuclear Regulatory Commission (NRC). It is designed on the basis of RESRAD (onsite) code, a computer code designated by DOE and NRC for evaluating soil-contaminated sites for compliance with human health protection requirements pertaining to license termination or environmental remediation. RESRAD-OFFSITE has enhanced capabilities of modeling radionuclide transport to offsite locations and calculating potential radiation exposure to offsite receptors. Recently, a new source term model was incorporated into RESRAD-OFFSITE to enhance its capability further. This new source term model allows simulation of radionuclide releases from different waste forms, in addition to the soil sources originally considered in RESRAD (onsite) and RESRAD-OFFSITE codes. With this new source term model, a variety of applications can be achieved by using RESRAD-OFFSITE, including but not limited to, assessing the performance of radioactive waste disposal facilities. This paper presents the comparison of radionuclide release rates calculated by the new source term model of RESRAD-OFFSITE versus those calculated by DUST-MS and GoldSim, respectively. The focus of comparison is on the release rates of radionuclides from the bottom of the contaminated zone that was assumed to contain radioactive source materials buried in soil. The transport of released contaminants outside of the primary contaminated zone is beyond the scope of this paper. Overall, the agreement between the RESRAD-OFFSITE results and the DUST-MS and GoldSim results is fairly good, with all three codes predicting identical or similar radionuclide release profiles over time. Numerical dispersion in the DUST-MS and GoldSim results was identified as potentially contributing to the disagreement in the release rates. In general, greater discrepancy in the release rates was found for short

  10. Benchmarking the New RESRAD-OFFSITE Source Term Model with DUST-MS and GoldSim - 13377

    International Nuclear Information System (INIS)

    Cheng, J.J.; Kamboj, S.; Gnanapragasam, E.; Yu, C.

    2013-01-01

    RESRAD-OFFSITE is a computer code developed by Argonne National Laboratory under the sponsorship of U.S. Department of Energy (DOE) and U.S. Nuclear Regulatory Commission (NRC). It is designed on the basis of RESRAD (onsite) code, a computer code designated by DOE and NRC for evaluating soil-contaminated sites for compliance with human health protection requirements pertaining to license termination or environmental remediation. RESRAD-OFFSITE has enhanced capabilities of modeling radionuclide transport to offsite locations and calculating potential radiation exposure to offsite receptors. Recently, a new source term model was incorporated into RESRAD-OFFSITE to enhance its capability further. This new source term model allows simulation of radionuclide releases from different waste forms, in addition to the soil sources originally considered in RESRAD (onsite) and RESRAD-OFFSITE codes. With this new source term model, a variety of applications can be achieved by using RESRAD-OFFSITE, including but not limited to, assessing the performance of radioactive waste disposal facilities. This paper presents the comparison of radionuclide release rates calculated by the new source term model of RESRAD-OFFSITE versus those calculated by DUST-MS and GoldSim, respectively. The focus of comparison is on the release rates of radionuclides from the bottom of the contaminated zone that was assumed to contain radioactive source materials buried in soil. The transport of released contaminants outside of the primary contaminated zone is beyond the scope of this paper. Overall, the agreement between the RESRAD-OFFSITE results and the DUST-MS and GoldSim results is fairly good, with all three codes predicting identical or similar radionuclide release profiles over time. Numerical dispersion in the DUST-MS and GoldSim results was identified as potentially contributing to the disagreement in the release rates. In general, greater discrepancy in the release rates was found for short

  11. Analysis of the primary source term for meltdown accidents using MELCOR 1.8.2

    International Nuclear Information System (INIS)

    Schmuck, P.

    1995-01-01

    The MELCOR code describing accident phenomena in the core and primary systems was used for source term calculations and - in the context of the MELCOR Cooperative Assessment Programme - for studying two-phase flows through components such as valves and chokes. Results of the latter studies in comparison to experiments gave hints for an improved calculation of momentum transfer between the phases. (orig.)

  12. Proposal for implementation of alternative source term in the nuclear power plant of Laguna Verde

    International Nuclear Information System (INIS)

    Bazan L, A.; Lopez L, M.; Vargas A, A.; Cardenas J, J. B.

    2009-10-01

    In 2010 the nuclear power plant of Laguna Verde will implement the extended power upbeat in both units of the plant. Agree with methodology of NEDC-33004P-A, (constant pressure power up rate), and the source term of core, for accidents evaluations, were increased in proportion to the ratio of power level. This means that for the case of a design basis accident of loss of coolant an increase of power of 15% originated an increase of 15% in dose to main control room. Using the method of NEDC-33004P-A to extended power upbeat conditions was determined that the dose value to main control room is very near to regulatory limit established by SRP 6.4. By the above and in order to recover the margin, the nuclear power plant of Laguna Verde will calculate an alternative source term following the criteria established in RG 1.183 (alternative radiological source term for evaluating DBA at nuclear power reactor). This approach also have a more realistic dose value using the criterion of 10-CFR-50.67, in addition is predicted to get the benefit of additional operational flexibilities. This paper present the proposal of implementing the alternative source term in Laguna Verde. (Author)

  13. Reciprocity relations and the mode conversion-absorption equation with an inhomogeneous source term

    International Nuclear Information System (INIS)

    Cho, S.; Swanson, D.G.

    1990-01-01

    The fourth-order mode conversion equation is solved completely via the Green's function to include an inhomogeneous source term. This Green's function itself contains all the plasma responsive effects such as mode conversion and absorption, and can be used to describe the spontaneous emission. In the course of the analysis, the reciprocity relations between coupling parameters are proved

  14. Short-Term Memory Stages in Sign vs. Speech: The Source of the Serial Span Discrepancy

    Science.gov (United States)

    Hall, Matthew L.; Bavelier, Daphne

    2011-01-01

    Speakers generally outperform signers when asked to recall a list of unrelated verbal items. This phenomenon is well established, but its source has remained unclear. In this study, we evaluate the relative contribution of the three main processing stages of short-term memory--perception, encoding, and recall--in this effect. The present study…

  15. Radioiodine source term and its potential impact on the use of potassium iodide

    International Nuclear Information System (INIS)

    Malinauskas, A.P.

    1982-01-01

    Information is presented concerning chemical forms of fission product iodine in the primary circuit; chemical forms of fission product iodine in the containment building; summary of iodine chemistry in light water reactor accidents; and impact of the radiodine source term on the potassium iodide issue

  16. New source terms: what do they tell us about engineered safety feature performance

    International Nuclear Information System (INIS)

    Bernero, R.M.

    1985-01-01

    The accident behavior models which are the basis of engineered safety feature design are generally simple, non-mechanistic and concentrated on volatile radioiodine. Now data from source term studies show that models should be more mechanistic and look at other species than volatile iodine. A complete reevaluation of engineered safety features is needed

  17. Model description for calculating the source term of the Angra 1 environmental control system

    International Nuclear Information System (INIS)

    Oliveira, L.F.S. de; Amaral Neto, J.D.; Salles, M.R.

    1988-01-01

    This work presents the model used for evaluation of source term released from Angra 1 Nuclear Power Plant in case of an accident. After that, an application of the model for the case of a Fuel Assembly Drop Accident Inside the Fuel Handling Building during reactor refueling is presented. (author) [pt

  18. Determination of Source Term for an Annual Stack Release of Gas Reactor G.A. Siwabessy

    International Nuclear Information System (INIS)

    Sudiyati; Syahrir; Unggul Hartoyo; Nugraha Luhur

    2008-01-01

    Releases of radionuclide from the reactor are noble gases, halogenides and particulates. The measurements were carried out directly on the air monitoring system of the stack. The results of these measurements are compared with the annual Source-Term data from the Safety Analyses report (SAR) of RSG-GAS. The measurement results are smaller than the data reported in SAR document. (author)

  19. Coarse Grid Modeling of Turbine Film Cooling Flows Using Volumetric Source Terms

    Science.gov (United States)

    Heidmann, James D.; Hunter, Scott D.

    2001-01-01

    The recent trend in numerical modeling of turbine film cooling flows has been toward higher fidelity grids and more complex geometries. This trend has been enabled by the rapid increase in computing power available to researchers. However, the turbine design community requires fast turnaround time in its design computations, rendering these comprehensive simulations ineffective in the design cycle. The present study describes a methodology for implementing a volumetric source term distribution in a coarse grid calculation that can model the small-scale and three-dimensional effects present in turbine film cooling flows. This model could be implemented in turbine design codes or in multistage turbomachinery codes such as APNASA, where the computational grid size may be larger than the film hole size. Detailed computations of a single row of 35 deg round holes on a flat plate have been obtained for blowing ratios of 0.5, 0.8, and 1.0, and density ratios of 1.0 and 2.0 using a multiblock grid system to resolve the flows on both sides of the plate as well as inside the hole itself. These detailed flow fields were spatially averaged to generate a field of volumetric source terms for each conservative flow variable. Solutions were also obtained using three coarse grids having streamwise and spanwise grid spacings of 3d, 1d, and d/3. These coarse grid solutions used the integrated hole exit mass, momentum, energy, and turbulence quantities from the detailed solutions as volumetric source terms. It is shown that a uniform source term addition over a distance from the wall on the order of the hole diameter is able to predict adiabatic film effectiveness better than a near-wall source term model, while strictly enforcing correct values of integrated boundary layer quantities.

  20. The BNL polarized H- ion source development program

    International Nuclear Information System (INIS)

    Kponou, A.; Alessi, J.; Hershcovitch, A.; DeVito, B.

    1992-01-01

    Polarized protons have been available for acceleration in the AGS for the high energy physics program since 1984. The polarized H - source, PONI-1, has routinely supplied a 0.4 Hz, 400 μsec pulse having a nominal intensity of 40 μA. Polarization is ∼80% out of the ion source. After PONI- 1 became operational, a program was initiated to develop a more intense source based on a cold ground state atomic beam source, followed by ionization of the polarized H degrees beam by D - charge exchange. Various phases of this work have been fully reported elsewhere, and only a summary is given here

  1. Overview of renewable energy sources development in France

    International Nuclear Information System (INIS)

    Lengyel, J.; Lepy, S.; Roudergues, J.M.

    2009-01-01

    Generation from Renewable Energy Sources is booming. As for any conventional generation technology, RES specific technical features can be accommodated by the electric system with no tremendous difficulty, provided the grid can be aptly adapted and developed. (authors)

  2. Development of ECR ion source for the HIMAC medical accelerator

    International Nuclear Information System (INIS)

    Kitagawa, A.; Yamada, S.; Sekiguchi, M.

    1992-01-01

    The development of the ECR ion source for the HIMAC injector is reported. The HIMAC facility has two types of the ion source, one is the PIG ion source and the other is the ECR ion source. The ECR ion source is especially expected long lifetime, easy operation, and easy maintenance for the medical use. Now, the system of the ion source is under construction. However, the tests of fundamental performances have been started. In the present tests, the output electrical currents of Ions are 1300 eμA of He 1+ , 210 eμA of Ne 3+ , and 100 eμA of Ar 6+ . And the good stability of the extracted beam is acquired. These performances satisfied the requirements for the radiotherapy. (author)

  3. Developments of saddle field ion sources and their applications

    International Nuclear Information System (INIS)

    Abdelrahman, M.M.; Helal, A.G.

    2009-01-01

    Ion sources should have different performance parameters according to the various applications for which they are used, ranging from ion beam production to high energy ion implanters. There are many kinds of ion sources, which produce different ion beams with different characteristics. This paper deals with the developments and applications of some saddle field ion sources which were designed and constructed in our lab. Theory of operation and types of saddle field ion sources are discussed in details. Some experimental results are given. The saddle field ion sources operate at low gas pressure and require neither magnetic field nor filament. This type of ion sources is used for many different applications as ion beam machining, sputtering, cleaning and profiling for surface analysis etc

  4. Renewable Energy Sources - Technologies and Development of the Economy

    International Nuclear Information System (INIS)

    Car, S.

    2010-01-01

    The usage of renewable energy sources is a substitute for usage of fossil fuels, whose quantities are limited, and it represents an essential contribution to the reduction of greenhouse gases; at the same time it has a great economic significance for the development of new industries and creation of new jobs. To speed up gradual transition from fossil to renewable sources, governments of all EU member states harmonise their legislations and subordinate regulations promoting investments in usage of renewable sources and thus creating opportunities for new jobs especially in the production of plants and equipment for utilisation of wind power, solar energy, small hydro power plants, biomass and other kinds of renewable sources. In the last 10 years Croatia has adopted a number of acts and regulations that also stimulate investors to utilise renewable sources, and the source of such subsidies is a higher price of electricity paid by all the consumers. On the other hand, the development of domestic industry and gaining references necessary for gaining new contracts are very difficult because of stiff international competition and foreign sources of finance, which often require purchase of foreign equipment as a condition for contract award. In such conditions the utilisation of renewable sources does not contribute either to economic development or creating new jobs in Croatia, but in the countries in which such equipment is produced.(author).

  5. Evaluation of short- and long-term fission product sources at the Fukushima Daiichi NPP

    International Nuclear Information System (INIS)

    Uchida, Shunsuke; Naitoh, Masanori; Suzuki, Hiroaki; Okada, Hidetoshi; Pellegrini, Marco; Achilli, Andrea; Hanamoto, Yukio; Sasaki, Hiroaki

    2014-01-01

    Research on fission product (FP) behaviors used to be one of the most important subjects in water chemistry but it is not done nowadays as a consequence of the increased integrity of nuclear fuels and the minimization of FP release into the environment. Evaluation of FP release into the environment is still one of the key issues for severe accident analysis, though. Although there have been a long quiet period in nuclear safety research, how to detect initiation of severe accidents, how to prevent them and how to mitigate them are still important subjects for nuclear engineering, and how to control the severe accidents after their occurrence, especially how to control FP release into the environment, has seldom been discussed in the water chemistry group recently. The paper is intended to address the issue of fewer activities for FP studies. FP sources are divided into two categories, short- and long-term FP sources. Short-term FP source can be evaluated based on the measured data obtained from monitoring posts (MPs), which give us clear evidence on the importance of radioactive iodine and cesium releases into the environment. It used to be considered that during primary containment vessel (PCV) venting, release of each element, e.g., iodine and cesium, was determined by the suppression pool scrubbing efficiency and most of the cesium would likely be removed in the pool due to its large scrubbing efficiency. But as a result of analyzing the MP data at early stage of the Fukushima Daiichi nuclear power plant (NPP) accident, it was confirmed that the releases of both elements were in proportion to their inventories in the reactors and their scrubbing efficiencies were almost the same. The scrubbing efficiency which increased with the pool water temperature became almost the same for iodine and cesium around the pool water boiling temperature. As a result of the mass balance analysis for FPs in the contaminated water accumulated in the Fukushima Daiichi plant site, it

  6. RF Negative Ion Source Development at IPP Garching

    International Nuclear Information System (INIS)

    Kraus, W.; McNeely, P.; Berger, M.; Christ-Koch, S.; Falter, H. D.; Fantz, U.; Franzen, P.; Froeschle, M.; Heinemann, B.; Leyer, S.; Riedl, R.; Speth, E.; Wuenderlich, D.

    2007-01-01

    IPP Garching is heavily involved in the development of an ion source for Neutral Beam Heating of the ITER Tokamak. RF driven ion sources have been successfully developed and are in operation on the ASDEX-Upgrade Tokamak for positive ion based NBH by the NB Heating group at IPP Garching. Building on this experience a RF driven H- ion source has been under development at IPP Garching as an alternative to the ITER reference design ion source. The number of test beds devoted to source development for ITER has increased from one (BATMAN) by the addition of two test beds (MANITU, RADI). This paper contains descriptions of the three test beds. Results on diagnostic development using laser photodetachment and cavity ringdown spectroscopy are given for BATMAN. The latest results for long pulse development on MANITU are presented including the to date longest pulse (600 s). As well, details of source modifications necessitated for pulses in excess of 100 s are given. The newest test bed RADI is still being commissioned and only technical details of the test bed are included in this paper. The final topic of the paper is an investigation into the effects of biasing the plasma grid

  7. Release modes and processes relevant to source-term calculations at Yucca Mountain

    International Nuclear Information System (INIS)

    Apted, M.J.

    1994-01-01

    The feasibility of permanent disposal of radioactive high-level waste (HLW) in repositories located in deep geologic formations is being studied world-wide. The most credible release pathway is interaction between groundwater and nuclear waste forms, followed by migration of radionuclide-bearing groundwater to the accessible environment. Under hydrologically unsaturated conditions, vapor transport of volatile radionuclides is also possible. The near-field encompasses the waste packages composed of engineered barriers (e.g. man-made materials, such as vitrified waste forms, corrosion-resistant containers), while the far-field includes the natural barriers (e.g. host rock, hydrologic setting). Taken together, these two subsystems define a series of multiple, redundant barriers that act to assure the safe isolation of nuclear waste. In the U.S., the Department of energy (DOE) is investigating the feasibility of safe, long-term disposal of high-level nuclear waste at the Yucca Mountain site in Nevada. The proposed repository horizon is located in non-welded tuffs within the unsaturated zone (i.e. above the water table) at Yucca Mountain. The purpose of this paper is to describe the source-term models for radionuclide release from waste packages at Yucca Mountain site. The first section describes the conceptual release modes that are relevant for this site and waste package design, based on a consideration of the performance of currently proposed engineered barriers under expected and unexpected conditions. No attempt is made to asses the reasonableness nor probability of occurrence for any specific release mode. The following section reviews the waste-form characteristics that are required to model and constrain the release of radionuclides from the waste package. The next section present mathematical models for the conceptual release modes, selected from those that have been implemented into a probabilistic total system assessment code developed for the Electric Power

  8. THE FOUNDATION OF ENGLISH BASIC TERM ECONOMICS AND ITS DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Khudinsha, E.A.

    2016-06-01

    Full Text Available The article shows the peculiarities of the English basic economical term origin “economics”, the dynamics of this term development. The lexical unit “economics” was based by the borrowing from Greek and Latin languages and began to be used actively in the meaning of the management of the household and modified to the term “economics” (the main modern economical science component.

  9. Inventory and source term evaluation of Russian nuclear power plants for marine applications

    International Nuclear Information System (INIS)

    Reistad, O.; Oelgaard, P.L.

    2006-04-01

    This report discusses inventory and source term properties in regard to operation and possible releases due to accidents from Russian marine reactor systems. The first part of the report discusses relevant accidents on the basis of both Russian and western sources. The overview shows that certain vessels were much more accident prone compared to others, in addition, there have been a noteworthy reduction in accidents the last two decades. However, during the last years new types of incidents, such as collisions, has occurred more frequently. The second part of the study considers in detail the most important factors for the source term; reactor operational characteristics and the radionuclide inventory. While Russian icebreakers has been operated on a similar basis as commercial power plants, the submarines has different power cyclograms which results in considerable lower values for fission product inventory. Theoretical values for radionuclide inventory are compared with computed results using the modelling tool HELIOS. Regarding inventory of transuranic elements, the results of the calculations are discussed in detail for selected vessels. Criticality accidents, loss-of-cooling accidents and sinking accidents are considered, bases on actual experiences with these types of accident and on theoretical considerations, and source terms for these accidents are discussed in the last chapter. (au)

  10. Inventory and source term evaluation of Russian nuclear power plants for marine applications

    Energy Technology Data Exchange (ETDEWEB)

    Reistad, O. [Norwegian Radiation Protection Authority (Norway); Oelgaard, P.L. [Risoe National Lab. (Denmark)

    2006-04-15

    This report discusses inventory and source term properties in regard to operation and possible releases due to accidents from Russian marine reactor systems. The first part of the report discusses relevant accidents on the basis of both Russian and western sources. The overview shows that certain vessels were much more accident prone compared to others, in addition, there have been a noteworthy reduction in accidents the last two decades. However, during the last years new types of incidents, such as collisions, has occurred more frequently. The second part of the study considers in detail the most important factors for the source term; reactor operational characteristics and the radionuclide inventory. While Russian icebreakers has been operated on a similar basis as commercial power plants, the submarines has different power cyclograms which results in considerable lower values for fission product inventory. Theoretical values for radionuclide inventory are compared with computed results using the modelling tool HELIOS. Regarding inventory of transuranic elements, the results of the calculations are discussed in detail for selected vessels. Criticality accidents, loss-of-cooling accidents and sinking accidents are considered, bases on actual experiences with these types of accident and on theoretical considerations, and source terms for these accidents are discussed in the last chapter. (au)

  11. Effect of hypoiodous acid volatility on the iodine source term in reactor accidents

    International Nuclear Information System (INIS)

    Routamo, T.

    1996-01-01

    A FORTRAN code ACT WATCH has been developed to establish an improved understanding of essential radionuclide behaviour mechanisms, especially related to iodine chemistry, in reactor accidents. The accident scenarios calculated in this paper are based on the Loss of Coolant accident at the Loviisa Nuclear Power Plant. The effect of different airborne species, especially HIO, on the iodine source term has been studied. The main cause of the high HIO release in the system modelled is the increase of I 2 hydrolysis rate along with the temperature increase, which accelerates HIO production. Due to the high radiation level near the reactor core, I 2 is produced from I - very rapidly. High temperature in the reactor coolant causes I 2 to be transformed into HIO and through the boiling of the coolant volatile I 2 and HIO are transferred efficiently into the gas phase. High filtration efficiency for particulate iodine causes I - release to be much lower than those of I 2 and HIO. (author) 15 figs., 1 tab., refs

  12. Effect of hypoiodous acid volatility on the iodine source term in reactor accidents

    Energy Technology Data Exchange (ETDEWEB)

    Routamo, T [Imatran Voima Oy, Vantaa (Finland)

    1996-12-01

    A FORTRAN code ACT WATCH has been developed to establish an improved understanding of essential radionuclide behaviour mechanisms, especially related to iodine chemistry, in reactor accidents. The accident scenarios calculated in this paper are based on the Loss of Coolant accident at the Loviisa Nuclear Power Plant. The effect of different airborne species, especially HIO, on the iodine source term has been studied. The main cause of the high HIO release in the system modelled is the increase of I{sub 2} hydrolysis rate along with the temperature increase, which accelerates HIO production. Due to the high radiation level near the reactor core, I{sub 2} is produced from I{sup -}very rapidly. High temperature in the reactor coolant causes I{sub 2} to be transformed into HIO and through the boiling of the coolant volatile I{sub 2} and HIO are transferred efficiently into the gas phase. High filtration efficiency for particulate iodine causes I{sup -} release to be much lower than those of I{sub 2} and HIO. (author) 15 figs., 1 tab., refs.

  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. Sensitivity analysis and benchmarking of the BLT low-level waste source term code

    International Nuclear Information System (INIS)

    Suen, C.J.; Sullivan, T.M.

    1993-07-01

    To evaluate the source term for low-level waste disposal, a comprehensive model had been developed and incorporated into a computer code, called BLT (Breach-Leach-Transport) Since the release of the original version, many new features and improvements had also been added to the Leach model of the code. This report consists of two different studies based on the new version of the BLT code: (1) a series of verification/sensitivity tests; and (2) benchmarking of the BLT code using field data. Based on the results of the verification/sensitivity tests, the authors concluded that the new version represents a significant improvement and it is capable of providing more realistic simulations of the leaching process. Benchmarking work was carried out to provide a reasonable level of confidence in the model predictions. In this study, the experimentally measured release curves for nitrate, technetium-99 and tritium from the saltstone lysimeters operated by Savannah River Laboratory were used. The model results are observed to be in general agreement with the experimental data, within the acceptable limits of uncertainty

  15. A Source-Term Based Boundary Layer Bleed/Effusion Model for Passive Shock Control

    Science.gov (United States)

    Baurle, Robert A.; Norris, Andrew T.

    2011-01-01

    A modeling framework for boundary layer effusion has been developed based on the use of source (or sink) terms instead of the usual practice of specifying bleed directly as a boundary condition. This framework allows the surface boundary condition (i.e. isothermal wall, adiabatic wall, slip wall, etc.) to remain unaltered in the presence of bleed. This approach also lends itself to easily permit the addition of empirical models for second order effects that are not easily accounted for by simply defining effective transpiration values. Two effusion models formulated for supersonic flows have been implemented into this framework; the Doerffer/Bohning law and the Slater formulation. These models were applied to unit problems that contain key aspects of the flow physics applicable to bleed systems designed for hypersonic air-breathing propulsion systems. The ability of each model to predict bulk bleed properties was assessed, as well as the response of the boundary layer as it passes through and downstream of a porous bleed system. The model assessment was performed with and without the presence of shock waves. Three-dimensional CFD simulations that included the geometric details of the porous plate bleed systems were also carried out to supplement the experimental data, and provide additional insights into the bleed flow physics. Overall, both bleed formulations fared well for the tests performed in this study. However, the sample of test problems considered in this effort was not large enough to permit a comprehensive validation of the models.

  16. Uncertainty analysis methods for quantification of source terms using a large computer code

    International Nuclear Information System (INIS)

    Han, Seok Jung

    1997-02-01

    Quantification of uncertainties in the source term estimations by a large computer code, such as MELCOR and MAAP, is an essential process of the current probabilistic safety assessments (PSAs). The main objectives of the present study are (1) to investigate the applicability of a combined procedure of the response surface method (RSM) based on input determined from a statistical design and the Latin hypercube sampling (LHS) technique for the uncertainty analysis of CsI release fractions under a hypothetical severe accident sequence of a station blackout at Young-Gwang nuclear power plant using MAAP3.0B code as a benchmark problem; and (2) to propose a new measure of uncertainty importance based on the distributional sensitivity analysis. On the basis of the results obtained in the present work, the RSM is recommended to be used as a principal tool for an overall uncertainty analysis in source term quantifications, while using the LHS in the calculations of standardized regression coefficients (SRC) and standardized rank regression coefficients (SRRC) to determine the subset of the most important input parameters in the final screening step and to check the cumulative distribution functions (cdfs) obtained by RSM. Verification of the response surface model for its sufficient accuracy is a prerequisite for the reliability of the final results obtained by the combined procedure proposed in the present work. In the present study a new measure has been developed to utilize the metric distance obtained from cumulative distribution functions (cdfs). The measure has been evaluated for three different cases of distributions in order to assess the characteristics of the measure: The first case and the second are when the distribution is known as analytical distributions and the other case is when the distribution is unknown. The first case is given by symmetry analytical distributions. The second case consists of two asymmetry distributions of which the skewness is non zero

  17. Short-term versus long-term approaches to the development of tourism-related policies

    OpenAIRE

    Dredge, Dianne

    2015-01-01

    Tourism policy development is an increasingly complex activity involving multiple public sector agencies, industry and community stakeholders and non-government organisations at different scales. This discussion paper examines the implications for tourism of governments adopting short- term versus long-term approaches to the development of tourism related policies and identifies policy considerations to maximize the growth potential of tourism. The key issue is to understand how governments c...

  18. A Source Term Calculation for the APR1400 NSSS Auxiliary System Components Using the Modified SHIELD Code

    International Nuclear Information System (INIS)

    Park, Hong Sik; Kim, Min; Park, Seong Chan; Seo, Jong Tae; Kim, Eun Kee

    2005-01-01

    The SHIELD code has been used to calculate the source terms of NSSS Auxiliary System (comprising CVCS, SIS, and SCS) components of the OPR1000. Because the code had been developed based upon the SYSTEM80 design and the APR1400 NSSS Auxiliary System design is considerably changed from that of SYSTEM80 or OPR1000, the SHIELD code cannot be used directly for APR1400 radiation design. Thus the hand-calculation is needed for the portion of design changes using the results of the SHIELD code calculation. In this study, the SHIELD code is modified to incorporate the APR1400 design changes and the source term calculation is performed for the APR1400 NSSS Auxiliary System components

  19. PARTITION: A program for defining the source term/consequence analysis interface in the NUREG--1150 probabilistic risk assessments

    International Nuclear Information System (INIS)

    Iman, R.L.; Helton, J.C.; Johnson, J.D.

    1990-05-01

    The individual plant analyses in the US Nuclear Regulatory Commission's reassessment of the risk from commercial nuclear power plants (NUREG-1150) consist of four parts: systems analysis, accident progression analysis, source term analysis, and consequence analysis. Careful definition of the interfaces between these parts is necessary for both information flow and computational efficiency. This document has been designed for users of the PARTITION computer program developed by the authors at Sandia National Laboratories for defining the interface between the source term analysis (performed with the XXSOR programs) and the consequence analysis (performed with the MACCS program). This report provides a tutorial that details how the interactive partitioning is performed, along with detailed information on the partitioning process. The PARTITION program was written in ANSI standard FORTRAN 77 to make the code as machine-independent (i.e., portable) as possible. 9 refs., 4 figs

  20. Loss of confinement of liquefied gases. Evaluation of the source term; Perte de confinement de gaz liquefies. Evaluation du terme source

    Energy Technology Data Exchange (ETDEWEB)

    Alix, P.; Novat, E.; Hocquet, J.; Bigot, J.P. [Ecole Nationale Superieure des Mines, Centre SPIN, 42 - Saint-Etienne (France)

    2001-07-01

    In this work, the states law corresponding to flow rate measurements of two-phase flows performed with five different fluid (water, butane, R11, ethyl acetate, methanol) is applied. This allows to show that the critical mass flux (which is used as source term in the scenario of loss of confinement in liquefied gas reservoirs) is a 'universal' function of the reduced initial pressure P{sub 0}{sup *}, which can be used for most of the single-constituent fluids of the processes industry. Thus it is easy to make a relatively precise estimation of the critical mass flux (uncertainty < 20% for P{sub 0}{sup *} < 15%) without the need of any model. It is shown also that no improvement of the models can be expected from the use of the vaporization kinetics. On the contrary, a qualitative consideration indicates that the use of the slip seems more promising. (J.S.)

  1. Development of hollow anode penning ion source for laboratory application

    Energy Technology Data Exchange (ETDEWEB)

    Das, B.K., E-mail: dasbabu31@gmail.com [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Autonagar, Visakhapatnam (India); Shyam, A.; Das, R. [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Autonagar, Visakhapatnam (India); Rao, A.D.P. [Department of Nuclear Physics, Andhra University, Visakhapatnam (India)

    2012-03-21

    The research work presented here focuses for the development of miniature penning type ion source. One hollow anode penning type ion source was developed in our laboratory. The size of the ion source is 38 mm diameter and 55 mm length. The ion source consists of two cathodes, a hollow anode and one piece of rare earth permanent magnet. The plasma was created in the plasma region between cathodes and the hollow anode. The J Multiplication-Sign B force in the region helps for efficient ionization of the gas even in the high vacuum region{approx}1 Multiplication-Sign 10{sup -5} Torr. The ions were extracted in the axial direction with help of the potential difference between the electrodes and the geometry of the extraction angle. The effect of the extraction electrode geometry for efficient extraction of the ions from the plasma region was examined. This ion source is a self extracted ion source. The self extracted phenomena reduce the cost and the size of the ion source. The extracted ion current was measured by a graphite probe. An ion current of more than 200 {mu}A was observed at the probe placed 70 mm apart from the extraction electrode. In this paper, the structure of the ion source, effect of operating pressure, potential difference and the magnetic field on the extracted ion current is reported.

  2. A well-balanced scheme for Ten-Moment Gaussian closure equations with source term

    Science.gov (United States)

    Meena, Asha Kumari; Kumar, Harish

    2018-02-01

    In this article, we consider the Ten-Moment equations with source term, which occurs in many applications related to plasma flows. We present a well-balanced second-order finite volume scheme. The scheme is well-balanced for general equation of state, provided we can write the hydrostatic solution as a function of the space variables. This is achieved by combining hydrostatic reconstruction with contact preserving, consistent numerical flux, and appropriate source discretization. Several numerical experiments are presented to demonstrate the well-balanced property and resulting accuracy of the proposed scheme.

  3. RF H-minus ion source development in China spallation neutron source

    Science.gov (United States)

    Chen, W.; Ouyang, H.; Xiao, Y.; Liu, S.; Lü, Y.; Cao, X.; Huang, T.; Xue, K.

    2017-08-01

    China Spallation Neutron Source (CSNS) phase-I project currently uses a Penning surface plasma H- ion source, which has a life time of several weeks with occasional sparks between high voltage electrodes. To extend the life time of the ion source and prepare for the CSNS phase-II, we are trying to develop a RF negative hydrogen ion source with external antenna. The configuration of the source is similar to the DESY external antenna ion source and SNS ion source. However several changes are made to improve the stability and the life time. Firstly, Si3N4 ceramic with high thermal shock resistance, and high thermal conductivity is used for plasma chamber, which can endure an average power of 2000W. Secondly, the water-cooled antenna is brazed on the chamber to improve the energy efficiency. Thirdly, cesium is injected directly to the plasma chamber if necessary, to simplify the design of the converter and the extraction. Area of stainless steel exposed to plasma is minimized to reduce the sputtering and degassing. Instead Mo, Ta, and Pt coated materials are used to face the plasma, which makes the self-cleaning of the source possible.

  4. A Source Term for Wave Attenuation by Sea Ice in WAVEWATCH III (registered trademark): IC4

    Science.gov (United States)

    2017-06-07

    blue and 4 locations in the ice: 1, 2, 5, and 10 km. Notice the steepening of the high frequency face and the shift of the peak to slightly lower...Term for Wave Attenuation by Sea Ice in WAVEWATCH III®: IC4 ClarenCe O. COllins iii W. eriCk rOgers Ocean Dynamics and Prediction Branch Oceanography...Wave model Sea ice Ocean surface waves Arctic Ocean WAVEWATCH III Spectral wave modeling Source terms Wave hindcasting 73-N2K2-07-5 Naval Research

  5. Development of WEB Applications of The Component – Open Source

    Directory of Open Access Journals (Sweden)

    Arturo Sergio Medina Castillo

    2013-06-01

    Full Text Available Nowadays software development not starting from scratch, however already has a set of tools provided by frameworks, which enables faster application development, relevant and indispensable factor for supporting continuous improvement processes seeking higher levels of competitiveness in this global society.In all respects the development of Web applications, whether open source or proprietary, is developing rapidly, by providing service levels of communication, interoperability, access to internal and external customers that allows management support different business processes.

  6. Calculation of the isotope concentrations, source terms and radiation shielding of the SAFARI-1 irradiation products

    International Nuclear Information System (INIS)

    Stoker, C.C.; Ball, G.

    2000-01-01

    The ever increasing expansion of the irradiation product portfolio of the SAFARI-1 reactor leads to the need to routinely calculate the radio-isotope concentrations and source terms for the materials irradiated in the reactor accurately. In addition to this, the required shielding for the transportation and processing of these irradiation products needs to be determined. In this paper the calculational methodology applied is described with special attention given to the spectrum dependence of the one-group cross sections of selected SAFARI-1 irradiation materials and the consequent effect on the determination of the isotope concentrations and source terms. Comparisons of the calculated isotopic concentrations and dose rates with experimental analysis and measurements provide confidence in the calculational methodologies and data used. (author)

  7. Final report of the inter institutional project ININ-CNSNS 'Source Terms specific for the CNLV'

    International Nuclear Information System (INIS)

    Anaya M, R.A.

    1991-02-01

    The purpose of the project inter institutional ININ-CNSNS 'Source Terms Specifies for the CNLV' it is the one of implanting in the computer CYBER (CDC 180-830) of the ININ, the 'Source Term Code Package' (STCP) and to make the operation tests and corresponding operation using the data of the sample problem, for finally to liberate the package, all time that by means of the analysis of the results it is consider appropriate. In this report the results of the are presented simulation of the sequence 'Energy Losses external' (Station blackout) and 'Lost total of CA with failure of the RCIC and success of the HPCS' both with data of the Laguna Verde Central. (Author)

  8. The SSI TOOLBOX Source Term Model SOSIM - Screening for important radionuclides and parameter sensitivity analysis

    Energy Technology Data Exchange (ETDEWEB)

    Avila Moreno, R.; Barrdahl, R.; Haegg, C.

    1995-05-01

    The main objective of the present study was to carry out a screening and a sensitivity analysis of the SSI TOOLBOX source term model SOSIM. This model is a part of the SSI TOOLBOX for radiological impact assessment of the Swedish disposal concept for high-level waste KBS-3. The outputs of interest for this purpose were: the total released fraction, the time of total release, the time and value of maximum release rate, the dose rates after direct releases of the biosphere. The source term equations were derived and simple equations and methods were proposed for calculation of these. A literature survey has been performed in order to determine a characteristic variation range and a nominal value for each model parameter. In order to reduce the model uncertainties the authors recommend a change in the initial boundary condition for solution of the diffusion equation for highly soluble nuclides. 13 refs.

  9. Long-term monitoring of molecular markers can distinguish different seasonal patterns of fecal indicating bacteria sources.

    Science.gov (United States)

    Riedel, Timothy E; Thulsiraj, Vanessa; Zimmer-Faust, Amity G; Dagit, Rosi; Krug, Jenna; Hanley, Kaitlyn T; Adamek, Krista; Ebentier, Darcy L; Torres, Robert; Cobian, Uriel; Peterson, Sophie; Jay, Jennifer A

    2015-03-15

    Elevated levels of fecal indicator bacteria (FIB) have been observed at Topanga Beach, CA, USA. To identify the FIB sources, a microbial source tracking study using a dog-, a gull- and two human-associated molecular markers was conducted at 10 sites over 21 months. Historical data suggest that episodic discharge from the lagoon at the mouth of Topanga Creek is the main source of bacteria to the beach. A decline in creek FIB/markers downstream from upper watershed development and a sharp increase in FIB/markers at the lagoon sites suggest sources are local to the lagoon. At the lagoon and beach, human markers are detected sporadically, dog marker peaks in abundance mid-winter, and gull marker is chronically elevated. Varied seasonal patterns of FIB and source markers were identified showing the importance of applying a suite of markers over long-term spatial and temporal sampling to identify a complex combination of sources of contamination. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Quantification of source-term profiles from near-field geochemical models

    International Nuclear Information System (INIS)

    McKinley, I.G.

    1985-01-01

    A geochemical model of the near-field is described which quantitatively treats the processes of engineered barrier degradation, buffering of aqueous chemistry by solid phases, nuclide solubilization and transport through the near-field and release to the far-field. The radionuclide source-terms derived from this model are compared with those from a simpler model used for repository safety analysis. 10 refs., 2 figs., 2 tabs

  11. Short-Term Memory Stages in Sign vs. Speech: The Source of the Serial Span Discrepancy

    OpenAIRE

    Hall, Matthew L.

    2011-01-01

    Speakers generally outperform signers when asked to recall a list of unrelated verbal items. This phenomenon is well established, but its source has remained unclear. In this study, we evaluate the relative contribution of the three main processing stages of short-term memory – perception, encoding, and recall – in this effect. The present study factorially manipulates whether American Sign Language (ASL) or English was used for perception, memory encoding, and recall in hearing ASL-English b...

  12. Short-term memory stages in sign vs. speech: The source of the serial span discrepancy

    OpenAIRE

    Hall, Matthew L.; Bavelier, Daphné

    2011-01-01

    Speakers generally outperform signers when asked to recall a list of unrelated verbal items. This phenomenon is well established, but its source has remained unclear. In this study, we evaluate the relative contribution of the three main processing stages of short-term memory – perception, encoding, and recall – in this effect. The present study factorially manipulates whether American Sign Language (ASL) or English is used for perception, memory encoding, and recall in hearing ASL-English bi...

  13. On the sequence of core-melt accidents: Fission product release, source terms and Chernobyl release

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, H

    1986-01-01

    There is a sketch of our ideas on the course of a core melt-out accident in a PWR. There is then a survey of the most important results on fission product release, which were obtained by experiments on the SASCHA melt-out plant. The 3rd part considers questions which are important for determining source terms for the environment and the last part contains some considerations on radioactivity release from the Chernobyl reactor.

  14. Refined Source Terms in WAVEWATCH III with Wave Breaking and Sea Spray Forecasts

    Science.gov (United States)

    2015-09-30

    dissipation and breaking, nonlinear wave-wave interaction, bottom friction, wave-mud interaction, wave-current interaction as well as sea spray flux. These...shallow water outside the surf zone. After careful testing within a comprehensive suite of test bed cases, these refined source terms will be...aim to refine the parameterization of air-sea and upper ocean fluxes, including wind input and sea spray as well as dissipation, and hence improve

  15. Optimization method for identifying the source term in an inverse wave equation

    Directory of Open Access Journals (Sweden)

    Arumugam Deiveegan

    2017-08-01

    Full Text Available In this work, we investigate the inverse problem of identifying a space-wise dependent source term of wave equation from the measurement on the boundary. On the basis of the optimal control framework, the inverse problem is transformed into an optimization problem. The existence and necessary condition of the minimizer for the cost functional are obtained. The projected gradient method and two-parameter model function method are applied to the minimization problem and numerical results are illustrated.

  16. Intrinsic Motivation versus Signaling in Open Source Software Development

    DEFF Research Database (Denmark)

    Bitzer, J; Schrettl, W; Schröder, P

    This papers sheds light on the puzzling fact that even though open source software (OSS) is a public good, it is developed for free by highly qualified, young, motivated individuals, and evolves at a rapid pace. We show that when OSS development is understood as the private provision of a public...

  17. Development and production of cobalt-60 sources for metallurgical application

    International Nuclear Information System (INIS)

    Oliveira, Paulo Fernando; Valente, Eduardo Sarmento; Maretti Junior, Fausto

    2002-01-01

    The CDTN has developed and produced 60 Co sources to be used in level controllers on continuous ingot casting. The sources used in these systems are sealed with a stainless steel revetment and have an useful life equivalent to one half life of the 60 Co (5.272 years). Each system of continuous ingot casting uses a source with one specified activity and different activation section. The sources have been imported with a very high cost due the special shields used to keep and transport them safety. One of its sources, with initial activity of 148 MBq, after being used for more than 5 years in one factory, was given to CDTN to carry out an activation section studies. After these studies be concluded CDTN/CNEN began the procedures to produce a new source in the IPR-R1 TRIGA Reactor, with an irradiation of one cobalt wire in the maximum flux region of the core. The same metallic cobalt wire was irradiated (10% of total activity), to determinate the necessary irradiation time to obtain the final activation. The CDTN developed too a stainless steel recipient with a aluminum nucleus, to seal and to guarantee the integrity of the source. (author)

  18. Development of QCD jets emitted by color-singlet sources

    International Nuclear Information System (INIS)

    Ellis, R.K.; Gunion, J.F.; Kalinowski, J.; Webber, B.R.

    1985-01-01

    We compare the angular-ordering approximation to QCD jet development with full calculations to order αsub(s) in the following cases: emission of quark jets by a color-singlet vector source (as in e + e - annihilation) and emission of gluon jets by a color-singlet scalar (Fsup(a)sub(μν)Fsup(aμν)) source. In contrast to the case of a color-octet (gluon) source, we find that the approximation is good in those regions of phase space where the next-to-leading corrections to the amplitude are large. (orig.)

  19. 1+-n+ ECR ION SOURCE DEVELOPMENT TEST STAND

    International Nuclear Information System (INIS)

    Donald P. May

    2006-01-01

    A test stand for the investigation of 1+-n+ charge boosting using an ECR ion sources is currently being assembled at the Texas A and M Cyclotron Institute. The ultimate goal is to relate the charge-boosting of ions of stable species to possible charge-boosting of ions of radioactive species extracted from the diverse, low-charge-state ion sources developed for radioactive ion beams

  20. Radioactive target and source development at Argonne National Laboratory

    International Nuclear Information System (INIS)

    Greene, J.P.; Ahmad, I.; Thomas, G.E.

    1992-01-01

    An increased demand for low-level radioactive targets has created the need for a laboratory dedicated to the production of these foils. A description is given of the radioactive target produced as well as source development work being performed at the Physics Division target facility of Argonne National Laboratory (ANL). Highlights include equipment used and the techniques employed. In addition, some examples of recent source preparation are given as well as work currently in progress

  1. Unsplit schemes for hyperbolic conservation laws with source terms in one space dimension

    International Nuclear Information System (INIS)

    Papalexandris, M.V.; Leonard, A.; Dimotakis, P.E.

    1997-01-01

    The present work is concerned with an application of the theory of characteristics to conservation laws with source terms in one space dimension, such as the Euler equations for reacting flows. Space-time paths are introduced on which the flow/chemistry equations decouple to a characteristic set of ODE's for the corresponding homogeneous laws, thus allowing the introduction of functions analogous to the Riemann invariants in classical theory. The geometry of these paths depends on the spatial gradients of the solution. This particular decomposition can be used in the design of efficient unsplit algorithms for the numerical integration of the equations. As a first step, these ideas are implemented for the case of a scalar conservation law with a nonlinear source term. The resulting algorithm belongs to the class of MUSCL-type, shock-capturing schemes. Its accuracy and robustness are checked through a series of tests. The stiffness of the source term is also studied. Then, the algorithm is generalized for a system of hyperbolic equations, namely the Euler equations for reacting flows. A numerical study of unstable detonations is performed. 57 refs

  2. Dose assessments for Greifswald and Cadarache with new source terms from ITER NSSR-1

    International Nuclear Information System (INIS)

    Raskob, W.; Forschungszentrum Karlsruhe GmbH Technik und Umwelt; Hasemann, I.

    1997-08-01

    Probabilistic dose assessments for accidental atmospheric releases of various ITER source terms which contain tritium and/or activation products were performed for the sites of Greifswald, Germany, and Cadarache, France. No country specific rules were applied and the input parameters were adapted as far as possible to those used within former ITER studies to achieve a better comparability with site independent dose assessments performed in the frame of ITER. The calculations were based on source terms which, at the first time, contain a combination of tritium and activation products. This allowed a better judgement of the contribution of the individual fusion relevant materials to the total dose. The results were compared to site independent dose limits defined in the frame of ITER. Source terms for two different categories, representing 'extremely unlikely events' (CAT-IV) and 'hypothetical sequences' (CAT-V), were investigated. In no cases, the release scenarios of category CAT-IV exceeded the ITER limits. In addition, early doses from the hypothetical scenarios of type CAT-V were still below 50 mSv or 100 mSv, values which are commonly used as lower reference values for evacuation in many potential home countries of ITER. Only the banning of food products was found to be a potential countermeasure which may affect larger areas. (orig.) [de

  3. Standardization of iridium-192 coiled source in terms of air kerma output

    International Nuclear Information System (INIS)

    Shanta, A.; Unnikrishnan, K.; Tripathi, U.B.; Kannan, A.; Iyer, P.S.

    1996-01-01

    ICRU (1985) recommended that the output of gamma ray brachytherapy sources should be specified in terms of reference air kerma rate, defined as the kerma rate to air in air at a reference distance of 1 meter, perpendicular to the long axis of the source, corrected for air attenuation and scattering. As these measurements are difficult to carry out in the routine clinical use, it is the common practice to calibrate the re-entrant ionization chamber with respect to open air measurements and use the re-entrant chamber for routine measurements. This paper reports on the measurements carried out to correlate the nominal activity and air kerma rate of 192 Ir wire sources supplied by the Board of Radiation and Isotope Technology, Department of Atomic Energy. (author). 3 refs, 1 tab

  4. Standardization of iridium-192 coiled source in terms of air kerma output

    Energy Technology Data Exchange (ETDEWEB)

    Shanta, A; Unnikrishnan, K; Tripathi, U B; Kannan, A; Iyer, P S [Bhabha Atomic Research Centre, Bombay (India)

    1996-08-01

    ICRU (1985) recommended that the output of gamma ray brachytherapy sources should be specified in terms of reference air kerma rate, defined as the kerma rate to air in air at a reference distance of 1 meter, perpendicular to the long axis of the source, corrected for air attenuation and scattering. As these measurements are difficult to carry out in the routine clinical use, it is the common practice to calibrate the re-entrant ionization chamber with respect to open air measurements and use the re-entrant chamber for routine measurements. This paper reports on the measurements carried out to correlate the nominal activity and air kerma rate of {sup 192}Ir wire sources supplied by the Board of Radiation and Isotope Technology, Department of Atomic Energy. (author). 3 refs, 1 tab.

  5. Study of the source term of radiation of the CDTN GE-PET trace 8 cyclotron with the MCNPX code

    Energy Technology Data Exchange (ETDEWEB)

    Benavente C, J. A.; Lacerda, M. A. S.; Fonseca, T. C. F.; Da Silva, T. A. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Vega C, H. R., E-mail: jhonnybenavente@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2015-10-15

    Full text: The knowledge of the neutron spectra in a PET cyclotron is important for the optimization of radiation protection of the workers and individuals of the public. The main objective of this work is to study the source term of radiation of the GE-PET trace 8 cyclotron of the Development Center of Nuclear Technology (CDTN/CNEN) using computer simulation by the Monte Carlo method. The MCNPX version 2.7 code was used to calculate the flux of neutrons produced from the interaction of the primary proton beam with the target body and other cyclotron components, during 18F production. The estimate of the source term and the corresponding radiation field was performed from the bombardment of a H{sub 2}{sup 18}O target with protons of 75 μA current and 16.5 MeV of energy. The values of the simulated fluxes were compared with those reported by the accelerator manufacturer (GE Health care Company). Results showed that the fluxes estimated with the MCNPX codes were about 70% lower than the reported by the manufacturer. The mean energies of the neutrons were also different of that reported by GE Health Care. It is recommended to investigate other cross sections data and the use of physical models of the code itself for a complete characterization of the source term of radiation. (Author)

  6. The continued development of the Spallation Neutron Source external antenna H- ion source

    International Nuclear Information System (INIS)

    Welton, R. F.; Carmichael, J.; Fuga, R.; Goulding, R. H.; Han, B.; Kang, Y.; Lee, S. W.; Murray, S. N.; Pennisi, T.; Potter, K. G.; Santana, M.; Stockli, M. P.; Desai, N. J.

    2010-01-01

    The U.S. Spallation Neutron Source (SNS) is an accelerator-based, pulsed neutron-scattering facility, currently in the process of ramping up neutron production. In order to ensure that the SNS will meet its operational commitments as well as provide for future facility upgrades with high reliability, we are developing a rf-driven, H - ion source based on a water-cooled, ceramic aluminum nitride (AlN) plasma chamber. To date, early versions of this source have delivered up to 42 mA to the SNS front end and unanalyzed beam currents up to ∼100 mA (60 Hz, 1 ms) to the ion source test stand. This source was operated on the SNS accelerator from February to April 2009 and produced ∼35 mA (beam current required by the ramp up plan) with availability of ∼97%. During this run several ion source failures identified reliability issues, which must be addressed before the source re-enters production: plasma ignition, antenna lifetime, magnet cooling, and cooling jacket integrity. This report discusses these issues, details proposed engineering solutions, and notes progress to date.

  7. PHARAO space atomic clock: new developments on the laser source

    Science.gov (United States)

    Saccoccio, Muriel; Loesel, Jacques; Coatantiec, Claude; Simon, Eric; Laurent, Philippe; Lemonde, Pierre; Maksimovic, I.; Abgrall, M.

    2017-11-01

    The PHARAO project purpose is to open the way for a new atomic clock generation in space, where laser cooling techniques and microgravity allow high frequency stability and accuracy. The French space agency, CNES is funding and managing the clock construction. The French SYRTE and LKB laboratories are scientific and technical advisers for the clock requirements and the follow-up of subsystem development in industrial companies. EADS SODERN is developing two main subsystems of the PHARAO clock: the Laser Source and the Cesium Tube where atoms are cooled, launched, selected and detected by laser beams. The Laser Source includes an optical bench and electronic devices to generate the laser beams required. This paper describes PHARAO and the role laser beams play in its principle of operation. Then we present the Laser Source design, the technologies involved, and the status of development. Lastly, we focus of a key equipment to reach the performances expected, which is the Extended Cavity Laser Diode.

  8. Development of radioactive source scanner based on PLC

    International Nuclear Information System (INIS)

    Yang Guogui; Gao Xiang; Guo Hongli

    2013-01-01

    The radioactive radial uniformity of 68 Ge line radioactive sources is a critical quality parameter. The radioactive source scanner with linear scanning function is developed by making use of high-speed pulse counters, high-speed pulse output ports, and the powerful instruction system of Siemens S7-200 series programmable logic controller (PLC). A computer used as a host computer of the instrument communicate with. the PLC by point to point interface (PPI) protocol, The instrument with functions of data collection, transmission, displaying, saving, motion control and instrument parameter settings, can be used to measure the radioactive radial uniformity and total activity of line radioactive source. The advantages of Using the PLC to develop nuclear instrumentation are development speed, strong anti-interference ability, and low-cost. This paper mainly describes the control system implementation and feature of the instrument. (authors)

  9. Inverse kinetics method with source term for subcriticality measurements during criticality approach in the IPEN/MB-01 research reactor

    International Nuclear Information System (INIS)

    Loureiro, Cesar Augusto Domingues; Santos, Adimir dos

    2009-01-01

    In reactor physics tests which are performed at the startup after refueling the commercial PWRs, it is important to monitor subcriticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor and it is possible to perform an online reactivity measurement based on the point reactor kinetics equations. This technique is successful applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected. For operation at low power levels, the contribution of the neutron source must be taken into account and this implies the knowledge of a quantity proportional to the source strength, and then it should be determined. Some experiments have been performed in the IPEN/MB-01 Research Reactor for the determination of the Source Term, using the Least Square Inverse Kinetics Method (LSIKM). A digital reactivity meter which neglects the source term is used to calculate the reactivity and then the source term can be determined by the LSIKM. After determining the source term, its value can be added to the algorithm and the reactivity can be determined again, considering the source term. The new digital reactivity meter can be used now to monitor reactivity during the criticality approach and the measured value for the reactivity is more precise than the meter which neglects the source term. (author)

  10. Development of radioactive sealed sources in epoxy matrix

    International Nuclear Information System (INIS)

    Benega, Marcos A.G.; Nagatomi, Helio R.; Rostelato, Maria Elisa C.M.; Karan Junior, Dib; Souza, Carla D.; Tiezzi, Rodrigo; Rodrigues, Bruna T.; Peleias Junior, Fernando S.

    2013-01-01

    The aim of the present work is to study and develop commercial resins for manufacturing solid sealed sources. The sources are produced with radionuclides of barium-133, cesium-137 and cobalt-57. They are used in radiation detectors verification. For the immobilization of the radionuclides in the epoxy matrix, it is made use of emulsifying agents that ensure the miscibility between resin and aqueous radioactive solution, as well as curing agents for controlling, curing and sealing the standard radioactive solution completely. As a result, it is expected to obtain standard sealed sources and equivalent to water. The equivalence to water is an important and necessary characteristic. The radioisotopes used in nuclear medicine are supplied in an aqueous form and the resin applied must have a very similar density comparing to the water. The sources must also be comparable in quality to sources produced internationally, but with low cost and wide available materials in the market. It is intended to create a national technology able to meet the demand of this product in the domestic market and achieve excellence in quality through accreditation and certification of the product by the appropriate agencies. The study of the necessary parameters used in the production of these sources, will bring technology for the manufacture of other categories of standard sealed sources, those used for nuclear medicine, image, laboratories and industry. (author)

  11. Evaluation on In-vessel Source Term in PGSFR (2015 Results)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Won; Chang, Won-Pyo; Ha, Kwi-Seok; Ahn, Sang June; Kang, Seok Hun; Choi, Chi-Woong; Lee, Kwi Lim; Jeong, Jae-Ho; Kim, Jin Su; Jeong, Taekyeong [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    This strategy requires nuclear plants to have features that prevent radionuclide release and multiple barriers to the escape from the plants of any radionuclides that are released despite preventive measures. Considerations of the ability to prevent and mitigate release of radionuclides arise at numerous places in the safety regulations of nuclear plants. The effectiveness of mitigative capabilities in nuclear plants is subject to quantitative analysis. The radionuclide input to these quantitative analyses of effectiveness is the Source Term (ST). All features of the composition, magnitude, timing, chemical form and physical form of accidental radionuclide release constitute the ST. Also, ST is defined as the release of radionuclides from the fuel and coolant into the containment, and subsequently to the environment. Since the TMI accident in 1979, extensive experimental and analytical information has been accumulated on the accident ST for LWRs. Such mechanistic models and computer codes as the MELCOR and MAAP have been developed. The results of extensive calculations and experiments have been used to formulate an alternative to the simple TID-14844 ST for regulatory purpose. The in-vessel STs are calculated through several phases: The inventory of each radionuclide is calculated by ORIGEN-2 code using the peak burnup conditions. The nominal value of the radiological inventory is multiplied by a factor of 1.1 as an uncertainty margin to give the radiological inventory. ST in the release from the core to primary sodium is calculated by using the assumption of 4S methodology. Lastly, ST in the release from the primary sodium to cover gas space is calculated by using the assumption of 4S methodology.

  12. Pulsed Cs beam development for the BNL polarized H- source

    International Nuclear Information System (INIS)

    Alessi, J.G.

    1983-01-01

    A pulsed Cs + beam has been developed for use on a polarized H - source. Cesium ion production is by surface ionization using a porous tungsten ionizer. While satisfactory current pulses (5 to 10 mA greater than or equal to 0.5 ms) can be obtained, the pulse shapes are a sensitive function of the ionizer temperature and Cs surface coverage. The beam optical requirements are stringent, and the optics have been studied experimentally for both Cs + and Cs 0 beams. Computer calculations are in good agreement with the observed results. The present source has delivered 2.6 mA of Cs + through the interaction region of the polarized ion source, and as much as 2.0 particle mA of Cs 0 . A new source is being built which is designed to give 15 mA through the interaction region

  13. Effect of seasonal and long-term changes in stress on sources of water to wells

    Science.gov (United States)

    Reilly, Thomas E.; Pollock, David W.

    1995-01-01

    The source of water to wells is ultimately the location where the water flowing to a well enters the boundary surface of the ground-water system . In ground-water systems that receive most of their water from areal recharge, the location of the water entering the system is at the water table . The area contributing recharge to a discharging well is the surface area that defines the location of the water entering the groundwater system. Water entering the system at the water table flows to the well and is eventually discharged from the well. Many State agencies are currently (1994) developing wellhead-protection programs. The thrust of some of these programs is to protect water supplies by determining the areas contributing recharge to water-supply wells and by specifying regulations to minimize the opportunity for contamination of the recharge water by activities at the land surface. In the analyses of ground-water flow systems, steady-state average conditions are frequently used to simplify the problem and make a solution tractable. Recharge is usually cyclic in nature, however, having seasonal cycles and longer term climatic cycles. A hypothetical system is quantitatively analyzed to show that, in many cases, these cyclic changes in the recharge rates apparently do not significantly affect the location and size of the areas contributing recharge to wells. The ratio of the mean travel time to the length of the cyclic stress period appears to indicate whether the transient effects of the cyclic stress must be explicitly represented in the analysis of contributing areas to wells. For the cases examined, if the ratio of the mean travel time to the period of the cyclic stress was much greater than one, then the transient area contributing recharge to wells was similar to the area calculated using an average steady-state condition. Noncyclic long-term transient changes in water use, however, and cyclic stresses on systems with ratios less than 1 can and do affect the

  14. Near term and long term materials issues and development needs for plasma interactive components

    International Nuclear Information System (INIS)

    Mattas, R.F.

    1986-01-01

    Plasma interactive components (PICs), including the first wall, limiter blades, divertor collector plates, halo scrapers, and RF launchers, are exposed to high particle fluxes that can result in high sputtering erosion rates and high heat fluxes. In addition, the materials in reactors are exposed to high neutron fluxes which will degrade the bulk properties. This severe environment will limit the materials and designs which can be used in fusion devices. In order to provide a reasonable degree of confidence that plasma interactive components will operate successfully, a comprehensive development program is needed. Materials research and development plays a key role in the successful development of PICs. The range of operating conditions along with a summary of the major issues for materials development is described. The areas covered include plasma/materials interactions, erosion/redeposition, baseline materials properties, fabrication, and irradiation damage effects. Candidate materials and materials development needs in the near term and long term are identified

  15. Advanced Monte Carlo procedure for the IFMIF d-Li neutron source term based on evaluated cross section data

    International Nuclear Information System (INIS)

    Simakov, S.P.; Fischer, U.; Moellendorff, U. von; Schmuck, I.; Konobeev, A.Yu.; Korovin, Yu.A.; Pereslavtsev, P.

    2002-01-01

    A newly developed computational procedure is presented for the generation of d-Li source neutrons in Monte Carlo transport calculations based on the use of evaluated double-differential d+ 6,7 Li cross section data. A new code M c DeLicious was developed as an extension to MCNP4C to enable neutronics design calculations for the d-Li based IFMIF neutron source making use of the evaluated deuteron data files. The M c DeLicious code was checked against available experimental data and calculation results of M c DeLi and MCNPX, both of which use built-in analytical models for the Li(d, xn) reaction. It is shown that M c DeLicious along with newly evaluated d+ 6,7 Li data is superior in predicting the characteristics of the d-Li neutron source. As this approach makes use of tabulated Li(d, xn) cross sections, the accuracy of the IFMIF d-Li neutron source term can be steadily improved with more advanced and validated data

  16. Advanced Monte Carlo procedure for the IFMIF d-Li neutron source term based on evaluated cross section data

    CERN Document Server

    Simakov, S P; Moellendorff, U V; Schmuck, I; Konobeev, A Y; Korovin, Y A; Pereslavtsev, P

    2002-01-01

    A newly developed computational procedure is presented for the generation of d-Li source neutrons in Monte Carlo transport calculations based on the use of evaluated double-differential d+ sup 6 sup , sup 7 Li cross section data. A new code M sup c DeLicious was developed as an extension to MCNP4C to enable neutronics design calculations for the d-Li based IFMIF neutron source making use of the evaluated deuteron data files. The M sup c DeLicious code was checked against available experimental data and calculation results of M sup c DeLi and MCNPX, both of which use built-in analytical models for the Li(d, xn) reaction. It is shown that M sup c DeLicious along with newly evaluated d+ sup 6 sup , sup 7 Li data is superior in predicting the characteristics of the d-Li neutron source. As this approach makes use of tabulated Li(d, xn) cross sections, the accuracy of the IFMIF d-Li neutron source term can be steadily improved with more advanced and validated data.

  17. Integrating HCI Specialists into Open Source Software Development Projects

    Science.gov (United States)

    Hedberg, Henrik; Iivari, Netta

    Typical open source software (OSS) development projects are organized around technically talented developers, whose communication is based on technical aspects and source code. Decision-making power is gained through proven competence and activity in the project, and non-technical end-user opinions are too many times neglected. In addition, also human-computer interaction (HCI) specialists have encountered difficulties in trying to participate in OSS projects, because there seems to be no clear authority and responsibility for them. In this paper, based on HCI and OSS literature, we introduce an extended OSS development project organization model that adds a new level of communication and roles for attending human aspects of software. The proposed model makes the existence of HCI specialists visible in the projects, and promotes interaction between developers and the HCI specialists in the course of a project.

  18. The Babel of software development : linguistic diversity in open source

    NARCIS (Netherlands)

    Vasilescu, B.N.; Serebrenik, A.; Brand, van den M.G.J.; Jatowt, A.; Lim, E.-P.; Ding, Y.

    2013-01-01

    Open source software (OSS) development communities are typically very specialised, on the one hand, and experience high turnover, on the other. Combination of specialization and turnover can cause parts of the system implemented in a certain programming language to become unmaintainable, if

  19. The Economics of Open Source Software Development: An Introduction

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Bitzer, Jürgen

    2006-01-01

    This chapter introduces the fundamentals of Open Source Software, its nature, the central economic aspects and the key mechanisms of its development. Furthermore, we present the themes of the book and provide a first overview for the reader by giving short summaries of its chapters....

  20. Exploring Coordination Structures in Open Source Software Development

    NARCIS (Netherlands)

    van Hillegersberg, Jos; Harmsen, Frank; Hegeman, J.H.; Amrit, Chintan Amrit; Geisberger, Eva; Keil, Patrick; Kuhrmann, Marco

    2007-01-01

    Coordination is difficult to achieve in a large globally distributed project setting. The problem is multiplied in open source software development projects, where most of the traditional means of coordination such as plans, system-level designs, schedules and defined process are not used. In order

  1. Short-term versus long-term approaches to the development of tourism-related policies

    DEFF Research Database (Denmark)

    Dredge, Dianne

    Tourism policy development is an increasingly complex activity involving multiple public sector agencies, industry and community stakeholders and non-government organisations at different scales. This discussion paper examines the implications for tourism of governments adopting short- term versus...... long-term approaches to the development of tourism related policies and identifies policy considerations to maximize the growth potential of tourism. The key issue is to understand how governments can strengthen their support for tourism growth and development by taking an integrated cross......-sector policy approach. The discussion paper commences by examining the unique character of tourism policyscape and recognises that it involves a wide variety of inter-linked policy sectors that often operate and develop policies in separate policy processes. Little attention is placed on cross-sector policy...

  2. Upgrade of the BATMAN test facility for H- source development

    Science.gov (United States)

    Heinemann, B.; Fröschle, M.; Falter, H.-D.; Fantz, U.; Franzen, P.; Kraus, W.; Nocentini, R.; Riedl, R.; Ruf, B.

    2015-04-01

    The development of a radio frequency (RF) driven source for negative hydrogen ions for the neutral beam heating devices of fusion experiments has been successfully carried out at IPP since 1996 on the test facility BATMAN. The required ITER parameters have been achieved with the prototype source consisting of a cylindrical driver on the back side of a racetrack like expansion chamber. The extraction system, called "Large Area Grid" (LAG) was derived from a positive ion accelerator from ASDEX Upgrade (AUG) using its aperture size (ø 8 mm) and pattern but replacing the first two electrodes and masking down the extraction area to 70 cm2. BATMAN is a well diagnosed and highly flexible test facility which will be kept operational in parallel to the half size ITER source test facility ELISE for further developments to improve the RF efficiency and the beam properties. It is therefore planned to upgrade BATMAN with a new ITER-like grid system (ILG) representing almost one ITER beamlet group, namely 5 × 14 apertures (ø 14 mm). Additionally to the standard three grid extraction system a repeller electrode upstream of the grounded grid can optionally be installed which is positively charged against it by 2 kV. This is designated to affect the onset of the space charge compensation downstream of the grounded grid and to reduce the backstreaming of positive ions from the drift space backwards into the ion source. For magnetic filter field studies a plasma grid current up to 3 kA will be available as well as permanent magnets embedded into a diagnostic flange or in an external magnet frame. Furthermore different source vessels and source configurations are under discussion for BATMAN, e.g. using the AUG type racetrack RF source as driver instead of the circular one or modifying the expansion chamber for a more flexible position of the external magnet frame.

  3. Upgrade of the BATMAN test facility for H− source development

    International Nuclear Information System (INIS)

    Heinemann, B.; Fröschle, M.; Falter, H.-D.; Fantz, U.; Franzen, P.; Kraus, W.; Nocentini, R.; Riedl, R.; Ruf, B.

    2015-01-01

    The development of a radio frequency (RF) driven source for negative hydrogen ions for the neutral beam heating devices of fusion experiments has been successfully carried out at IPP since 1996 on the test facility BATMAN. The required ITER parameters have been achieved with the prototype source consisting of a cylindrical driver on the back side of a racetrack like expansion chamber. The extraction system, called “Large Area Grid” (LAG) was derived from a positive ion accelerator from ASDEX Upgrade (AUG) using its aperture size (ø 8 mm) and pattern but replacing the first two electrodes and masking down the extraction area to 70 cm2. BATMAN is a well diagnosed and highly flexible test facility which will be kept operational in parallel to the half size ITER source test facility ELISE for further developments to improve the RF efficiency and the beam properties. It is therefore planned to upgrade BATMAN with a new ITER-like grid system (ILG) representing almost one ITER beamlet group, namely 5 × 14 apertures (ø 14 mm). Additionally to the standard three grid extraction system a repeller electrode upstream of the grounded grid can optionally be installed which is positively charged against it by 2 kV. This is designated to affect the onset of the space charge compensation downstream of the grounded grid and to reduce the backstreaming of positive ions from the drift space backwards into the ion source. For magnetic filter field studies a plasma grid current up to 3 kA will be available as well as permanent magnets embedded into a diagnostic flange or in an external magnet frame. Furthermore different source vessels and source configurations are under discussion for BATMAN, e.g. using the AUG type racetrack RF source as driver instead of the circular one or modifying the expansion chamber for a more flexible position of the external magnet frame

  4. Long-term storage life of light source modules by temperature cycling accelerated life test

    International Nuclear Information System (INIS)

    Sun Ningning; Tan Manqing; Li Ping; Jiao Jian; Guo Xiaofeng; Guo Wentao

    2014-01-01

    Light source modules are the most crucial and fragile devices that affect the life and reliability of the interferometric fiber optic gyroscope (IFOG). While the light emitting chips were stable in most cases, the module packaging proved to be less satisfactory. In long-term storage or the working environment, the ambient temperature changes constantly and thus the packaging and coupling performance of light source modules are more likely to degrade slowly due to different materials with different coefficients of thermal expansion in the bonding interface. A constant temperature accelerated life test cannot evaluate the impact of temperature variation on the performance of a module package, so the temperature cycling accelerated life test was studied. The main failure mechanism affecting light source modules is package failure due to solder fatigue failure including a fiber coupling shift, loss of cooling efficiency and thermal resistor degradation, so the Norris-Landzberg model was used to model solder fatigue life and determine the activation energy related to solder fatigue failure mechanism. By analyzing the test data, activation energy was determined and then the mean life of light source modules in different storage environments with a continuously changing temperature was simulated, which has provided direct reference data for the storage life prediction of IFOG. (semiconductor devices)

  5. Modification to ORIGEN2 for generating N Reactor source terms. Volume 1

    International Nuclear Information System (INIS)

    Schwarz, R.A.

    1997-04-01

    This report discusses work that has been done to upgrade the ORIGEN2 code cross sections to be compatible with the WIMS computer code data. Because of the changes in the ORIGEN2 calculations. Details on changes made to the ORIGEN2 computer code and the Radnuc code will be discussed along with additional work that should be done in the future to upgrade both ORIGEN2 and Radnuc. A detailed historical description of how source terms have been generated for N Reactor fuel stored in the K Basins has been generated. The neutron source discussed in this description was generated by the WIMS computer code (Gubbins et al. 1982) because of known shortcomings in the ORIGEN2 (Croff 1980) cross sections. Another document includes a discussion of the ORIGEN2 cross sections

  6. Source Term Characterization for Structural Components in 17 x 17 KOFA Spent Fuel Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Dong Keun; Kook, Dong Hak; Choi, Heui Joo; Choi, Jong Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-12-15

    Source terms of metal waste comprising a spent fuel assembly are relatively important when the spent fuel is pyroprocessed, because cesium, strontium, and transuranics are not a concern any more in the aspect of source term of permanent disposal. In this study, characteristics of radiation source terms for each structural component in spent fuel assembly was analyzed by using ORIGEN-S with a assumption that 10 metric tons of uranium is pyroprocessed. At first, mass and volume for each structural component of the fuel assembly were calculated in detail. Activation cross section library was generated by using KENO-VI/ORIGEN-S module for top-end piece and bottom-end piece, because those are located at outer core with different neutron spectrum compared to that of inner core. As a result, values of radioactivity, decay heat, and hazard index were reveled to be 1.40 x 10{sup 15} Bequerels, 236 Watts, 4.34 x 10{sup 9} m{sup 3}-water, respectively, at 10 years after discharge. Those values correspond to 0.7 %, 1.1 %, 0.1 %, respectively, compared to that of spent fuel. Inconel 718 grid plate was shown to be the most important component in the all aspects of radioactivity, decay heat, and hazard index although the mass occupies only 1 % of the total. It was also shown that if the Inconel 718 grid plate is managed separately, the radioactivity and hazard index of metal waste could be decreased to 20 {approx} 45 % and 30 {approx} 45 %, respectively. As a whole, decay heat of metal waste was shown to be negligible in the aspect of disposal system design, while the radioactivity and hazard index are important.

  7. Source Term Characteristics Analysis for Structural Components in PWR spent fuel assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kook, Dong Hak; Choi, Heui Joo; Cho, Dong Keun [KAERI, Daejeon (Korea, Republic of)

    2010-12-15

    Source terms of metal waste comprising a spent fuel assembly are relatively important when the spent fuel is pyroprocessed, because cesium, strontium, and transuranics are not a concern any more in the aspect of source term of permanent disposal. In this study, characteristics of radiation source terms for each structural component in spent fuel assembly was analyzed by using ORIGEN-S with a assumption that 10 metric tons of uranium is pyroprocessed. At first, mass and volume for each structural component of the fuel assembly were calculated in detail. Activation cross section library was generated by using KENO-VI/ORIGEN-S module for top-end piece and bottom-end piece, because those are located at outer core under different neutron spectrum compared to that of inner core. As a result, values of radioactivity, decay heat, and hazard index were reveled to be 1.32x1015 Bequerels, 238 Watts, 4.32x109 m3 water, respectively, at 10 years after discharge. Those values correspond to 0.6 %, 1.1 %, 0.1 %, respectively, compared to that of spent fuel. Inconel 718 grid plate was shown to be the most important component in the all aspects of radioactivity, decay heat, and hazard index although the mass occupies only 1 % of the total. It was also shown that if the Inconel 718 grid plate is managed separately, the radioactivity and hazard index of metal waste could be decreased to 25{approx}50 % and 35{approx}40 %, respectively. As a whole, decay heat of metal waste was shown to be negligible in the aspect of disposal system design, while the radioactivity and hazard index are important

  8. Long term plan of atomic energy development and utilization

    International Nuclear Information System (INIS)

    1982-01-01

    The atomic energy utilization and development in Japan have progressed remarkably, and already nuclear power generation has borne an important part in electric power supply, while radiation has been utilized in the fields of industry, agriculture, medicine and so on. Now, atomic energy is indispensable for national life and industrial activity. The former long term plan was decided in September, 1978, and the new long term plan should be established since the situation has changed largely. The energy substituting for petroleum has been demanded, and the expectation to nuclear power generation has heightened because it enables stable and economical power supply. The independently developed technology related to atomic energy must be put in practical use. The peaceful utilization of atomic energy must be promoted, while contributing to the nuclear non-proliferation policy. The Atomic Energy Commission of Japan decided the new long term plan to clearly show the outline of the important measures related to atomic energy development and utilization in 10 years hereafter, and the method of its promotion. The basic concept of atomic energy development and utilization, the long term prospect and the concept on the promotion, the method of promoting the development and utilization, and the problems of funds, engineers and location are described. (kako, I.)

  9. Basic repository source term and data sheet report: Deaf Smith County

    International Nuclear Information System (INIS)

    1987-01-01

    This report is one of a series describing studies undertaken in support of the US Department of Energy Civilian Radioactive Waste Management (CRWM) Program. This study contains the derivation of values for environmental source terms and resources consumed for a CRWM repository. Estimates include heavy construction equipment; support equipment; shaft-sinking equipment; transportation equipment; and consumption of fuel, water, electricity, and natural gas. Data are presented for construction and operation at an assumed site in Deaf Smith County, Texas. 2 refs., 6 tabs

  10. EXPERIENCES FROM THE SOURCE-TERM ANALYSIS OF A LOW AND INTERMEDIATE LEVEL RADWASTE DISPOSAL FACILITY

    International Nuclear Information System (INIS)

    Park, Jin Beak; Park, Joo-Wan; Lee, Eun-Young; Kim, Chang-Lak

    2003-01-01

    Enhancement of a computer code SAGE for evaluation of the Korean concept for a LILW waste disposal facility is discussed. Several features of source term analysis are embedded into SAGE to analyze: (1) effects of degradation mode of an engineered barrier, (2) effects of dispersion phenomena in the unsaturated zone and (3) effects of time dependent sorption coefficient in the unsaturated zone. IAEA's Vault Safety Case (VSC) approach is used to demonstrate the ability of this assessment code. Results of MASCOT are used for comparison purposes. These enhancements of the safety assessment code, SAGE, can contribute to realistic evaluation of the Korean concept of the LILW disposal project in the near future

  11. Description of apparatus for determining radiological source terms of nuclear fuels

    International Nuclear Information System (INIS)

    Baldwin, D.L.; Woodley, R.E.; Holt, F.E.; Archer, D.V.; Steele, R.T.; Whitkop, P.G.

    1985-01-01

    New apparatus have been designed, built and are currently being employed to measure the release of volatile fission products from irradiated nuclear fuel. The system is capable of measuring radiological source terms, particularly for cesium-137, cesium-134, iodine-129 and krypton-85, in various atmospheres at temperatures up to 1200 0 C. The design allows a rapid transient heatup from ambient to full temperature, a hold at maximum temperature for a specified period, and rapid cooldown. Released fission products are measured as deposition on a platinum thermal gradient tube or in a filter/charcoal trap. Noble gases pass through to a multi-channel gamma analyzer. 1 ref., 4 figs

  12. The uranium source-term mineralogy and geochemistry at the Broubster natural analogue site, Caithness

    International Nuclear Information System (INIS)

    Milodowski, A.E.; Pearce, J.M.; Basham, I.R.; Hyslop, E.K.

    1991-01-01

    The British Geological Survey (BGS) has been conducting a coordinated research programme at the Broubster natural analogue site in Caithness, north Scotland. This work on a natural radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report is one of a series being produced and it concentrates on the mineralogical characterization of the uranium distribution in the limestone unit considered as the 'source-term' in the natural analogue model

  13. A source term and risk calculations using level 2+PSA methodology

    International Nuclear Information System (INIS)

    Park, S. I.; Jea, M. S.; Jeon, K. D.

    2002-01-01

    The scope of Level 2+ PSA includes the assessment of dose risk which is associated with the exposures of the radioactive nuclides escaping from nuclear power plants during severe accidents. The establishment of data base for the exposure dose in Korea nuclear power plants may contribute to preparing the accident management programs and periodic safety reviews. In this study the ORIGEN, MELCOR and MACCS code were employed to produce a integrated framework to assess the radiation source term risk. The framework was applied to a reference plant. Using IPE results, the dose rate for the reference plant was calculated quantitatively

  14. The source term and waste optimization of molten salt reactors with processing

    International Nuclear Information System (INIS)

    Gat, U.; Dodds, H.L.

    1993-01-01

    The source term of a molten salt reactor (MSR) with fuel processing is reduced by the ratio of processing time to refueling time as compared to solid fuel reactors. The reduction, which can be one to two orders of magnitude, is due to removal of the long-lived fission products. The waste from MSRs can be optimized with respect to its chemical composition, concentration, mixture, shape, and size. The actinides and long-lived isotopes can be separated out and returned to the reactor for transmutation. These features make MSRs more acceptable and simpler in operation and handling

  15. Basic repository source term and data sheet report, Cypress Creek Dome: Draft

    International Nuclear Information System (INIS)

    1988-01-01

    This report is one of a series describing studies undertaken in support of the US Department of Energy Civilian Radioactive Waste Management (CRWM) Program. This study contains the derivation of values for environmental source terms and resources consumed for a CRWM repository. Estimates include heavy construction equipment; support equipment; shaft-sinking equipment; transportation equipment; and consumption of fuel, water, electricity, and natural gas. Data are presented for construction and operation at an assumed site in Cypress Creek Dome, Mississippi. 2 refs., 6 tabs

  16. Dose assessments for Greifswald and Cadarache with updated source terms from ITER NSSR-2

    International Nuclear Information System (INIS)

    Raskob, W.; Hasemann, I.

    1998-08-01

    The International Thermonuclear Experimental Reactor ITER is in its late engineering phase. One of the most important safety aspects - in particular for achieving public acceptance - is to assure that the releases of harzardous material are minimal during normal operation and for accidental events, even if very unlikely. To this purpose probabilistic dose assessments for accidental atmospheric releases of various ITER source terms which contain tritium and/or activation products were performed for the sites of Greifswald, Germany, and Cadarache, France. In addition, routine releases into the atmosphere and hydrosphere have been evaluated. No country specific rules were applied and the input parameters were adapted as far as possible to those used within former studies to achieve a better comparability with site independent dose assessments performed in the frame of ITER. The calculations were based on source terms which, for the first time, contain a combination of tritium and activation products. This allowed a better judgment of the contribution to the total dose of the individual fusion relevant materials. The results were compared to site independent dose limits defined in the frame of ITER. Annual doses from routine releases (CAT-I) are below 0.1 μSv for the aquatic scenarios and are close to 1 μSv for the atmospheric source terms. Source terms for two different categories of accidental releases, representing 'extremely unlikely events' (CAT-IV) and 'hypothetical sequences' (CAT-V), were investigated. In none of these cases, the release scenarios of category CAT-IV exceed the ITER limits. In addition, relevant characteristic quantities of the early dose distribution from the hypothetical scenarios of type CAT-V are still below 50 mSv or 100 mSv, values which are commonly used as lower reference values for evacuation in many potential home countries of ITER. These site specific assessments confirmed that the proposed release limits and thus the derived dose

  17. Design parameters and source terms: Volume 1, Design parameters: Revision 0

    International Nuclear Information System (INIS)

    1987-09-01

    The Design Parameters and Source Terms Document was prepared in accordance with DOE request and to provide data for the environmental impact study to be performed in the future for the Deaf Smith County, Texas site for a nuclear waste repository in salt. This document updates a previous unpublished report to the level of the Site Characterization Plan - Conceptual Design Report, SCP-CDR. The previous unpublished SCC Study identified the data needs for the Environmental Assessment effort for seven possible salt repository sites

  18. OpenADR Open Source Toolkit: Developing Open Source Software for the Smart Grid

    Energy Technology Data Exchange (ETDEWEB)

    McParland, Charles

    2011-02-01

    Demand response (DR) is becoming an increasingly important part of power grid planning and operation. The advent of the Smart Grid, which mandates its use, further motivates selection and development of suitable software protocols to enable DR functionality. The OpenADR protocol has been developed and is being standardized to serve this goal. We believe that the development of a distributable, open source implementation of OpenADR will benefit this effort and motivate critical evaluation of its capabilities, by the wider community, for providing wide-scale DR services

  19. Adiabatic energization in the ring current and its relation to other source and loss terms

    Science.gov (United States)

    Liemohn, M. W.; Kozyra, J. U.; Clauer, C. R.; Khazanov, G. V.; Thomsen, M. F.

    2002-04-01

    The influence of adiabatic energization and deenergization effects, caused by particle drift in radial distance, on ring current growth rates and loss lifetimes is investigated. Growth and loss rates from simulation results of four storms (5 June 1991, 15 May 1997, 19 October 1998, and 25 September 1998) are examined and compared against the y component of the solar wind electric field (Ey,sw). Energy change rates with and without the inclusion of adiabatic energy changes are considered to isolate the influence of this mechanism in governing changes of ring current strength. It is found that the influence of adiabatic drift effects on the energy change rates is very large when energization and deenergization are considered separately as gain and loss mechanisms, often about an order of magnitude larger than all other source or loss terms combined. This is true not only during storm times, when the open drift path configuration of the hot ions dominates the physics of the ring current, but also during quiet times, when the small oscillation in L of the closed trajectories creates a large source and loss of energy each drift orbit. However, the net energy change from adiabatic drift is often smaller than other source and loss processes, especially during quiet times. Energization from adiabatic drift dominates ring current growth only during portions of the main phase of storms. Furthermore, the net-adiabatic energization is often positive, because some particles are lost in the inner magnetosphere before they can adiabatically deenergize. It is shown that the inclusion of only this net-adiabatic drift effect in the total source rate or loss lifetime (depending on the sign of the net-adiabatic energization) best matches the observed source and loss values from empirical Dst predictor methods (that is, for consistency, these values should be compared between the calculation methods). While adiabatic deenergization dominates the loss timescales for all Ey,sw values

  20. Methodology for and uses of a radiological source term assessment for potential impacts to stormwater and groundwater

    International Nuclear Information System (INIS)

    Teare, A.; Hansen, K.; DeWilde, J.; Yu, L.; Killey, D.

    2001-01-01

    A Radiological Source Term Assessment (RSTA) was conducted by Ontario Power Generation Inc. (OPG) at the Pickering Nuclear Generating Station (PNGS). Tritium had been identified in the groundwater at several locations under the station, and OPG initiated the RSTA as part of its ongoing efforts to improve operations and to identify potential sources of radionuclide impact to groundwater and stormwater at the station. The RSTA provides a systematic approach to collecting information and assessing environmental risk for radioactive contaminants based on a ranking system developed for the purpose. This paper provides an overview of the RSTA focusing on the investigative approach and how it was applied. This approach can find application at other generating stations. (author)

  1. Source term evaluation model for high-level radioactive waste repository with decay chain build-up.

    Science.gov (United States)

    Chopra, Manish; Sunny, Faby; Oza, R B

    2016-09-18

    A source term model based on two-component leach flux concept is developed for a high-level radioactive waste repository. The long-lived radionuclides associated with high-level waste may give rise to the build-up of activity because of radioactive decay chains. The ingrowths of progeny are incorporated in the model using Bateman decay chain build-up equations. The model is applied to different radionuclides present in the high-level radioactive waste, which form a part of decay chains (4n to 4n + 3 series), and the activity of the parent and daughter radionuclides leaching out of the waste matrix is estimated. Two cases are considered: one when only parent is present initially in the waste and another where daughters are also initially present in the waste matrix. The incorporation of in situ production of daughter radionuclides in the source is important to carry out realistic estimates. It is shown that the inclusion of decay chain build-up is essential to avoid underestimation of the radiological impact assessment of the repository. The model can be a useful tool for evaluating the source term of the radionuclide transport models used for the radiological impact assessment of high-level radioactive waste repositories.

  2. Development of a versatile multiaperture negative ion source

    International Nuclear Information System (INIS)

    Cavenago, M.; Kulevoy, T.; Petrenko, S.; Serianni, G.; Antoni, V.; Bigi, M.; Fellin, F.; Recchia, M.; Veltri, P.

    2012-01-01

    A 60 kV ion source (9 beamlets of 15 mA each of H - ) and plasma generators are being developed at Consorzio RFX and INFN-LNL, for their versatility in experimental campaigns and for training. Unlike most experimental sources, the design aimed at continuous operation. Magnetic configuration can achieve a minimum |B| trap, smoothly merged with the extraction filter. Modular design allows for quick substitution and upgrading of parts such as the extraction and postacceleration grids or the electrodes in contact with plasma. Experiments with a radio frequency plasma generator and Faraday cage inside the plasma are also described.

  3. Development of a versatile multiaperture negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Cavenago, M. [INFN-LNL, viale dell' Universita n.2, I-35020 Legnaro (Padova) (Italy); Kulevoy, T.; Petrenko, S. [INFN-LNL, viale dell' Universita n.2, I-35020 Legnaro (Padova) (Italy); ITEP, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation); Serianni, G.; Antoni, V.; Bigi, M.; Fellin, F.; Recchia, M.; Veltri, P. [Consorzio RFX, Associazione Euratom-ENEA sulla fusione, c.so S. Uniti 4, 35127 Padova (Italy)

    2012-02-15

    A 60 kV ion source (9 beamlets of 15 mA each of H{sup -}) and plasma generators are being developed at Consorzio RFX and INFN-LNL, for their versatility in experimental campaigns and for training. Unlike most experimental sources, the design aimed at continuous operation. Magnetic configuration can achieve a minimum |B| trap, smoothly merged with the extraction filter. Modular design allows for quick substitution and upgrading of parts such as the extraction and postacceleration grids or the electrodes in contact with plasma. Experiments with a radio frequency plasma generator and Faraday cage inside the plasma are also described.

  4. Development of a versatile multiaperture negative ion source.

    Science.gov (United States)

    Cavenago, M; Kulevoy, T; Petrenko, S; Serianni, G; Antoni, V; Bigi, M; Fellin, F; Recchia, M; Veltri, P

    2012-02-01

    A 60 kV ion source (9 beamlets of 15 mA each of H(-)) and plasma generators are being developed at Consorzio RFX and INFN-LNL, for their versatility in experimental campaigns and for training. Unlike most experimental sources, the design aimed at continuous operation. Magnetic configuration can achieve a minimum ∣B∣ trap, smoothly merged with the extraction filter. Modular design allows for quick substitution and upgrading of parts such as the extraction and postacceleration grids or the electrodes in contact with plasma. Experiments with a radio frequency plasma generator and Faraday cage inside the plasma are also described.

  5. Open source tools for ATR development and performance evaluation

    Science.gov (United States)

    Baumann, James M.; Dilsavor, Ronald L.; Stubbles, James; Mossing, John C.

    2002-07-01

    Early in almost every engineering project, a decision must be made about tools; should I buy off-the-shelf tools or should I develop my own. Either choice can involve significant cost and risk. Off-the-shelf tools may be readily available, but they can be expensive to purchase and to maintain licenses, and may not be flexible enough to satisfy all project requirements. On the other hand, developing new tools permits great flexibility, but it can be time- (and budget-) consuming, and the end product still may not work as intended. Open source software has the advantages of both approaches without many of the pitfalls. This paper examines the concept of open source software, including its history, unique culture, and informal yet closely followed conventions. These characteristics influence the quality and quantity of software available, and ultimately its suitability for serious ATR development work. We give an example where Python, an open source scripting language, and OpenEV, a viewing and analysis tool for geospatial data, have been incorporated into ATR performance evaluation projects. While this case highlights the successful use of open source tools, we also offer important insight into risks associated with this approach.

  6. Development of the Dutch primary standard for beta-emitting brachytherapy sources

    International Nuclear Information System (INIS)

    Marel, J. an der; Dijk, E. van

    2002-01-01

    The application of β-radiation emitting radioactive sources in medicine is rapidly expanding. An important new application is the use of β-radiation emitting radioactive sources in endovascular brachytherapy to avoid restenosis. Another well-known application is the use of the ophthalmic applicator (flat or concave surface source) for the treatment of tumors in the eye. Dose and dose distributions are very important characteristics of brachytherapy sources. The absorbed dose in the treated tissue should be known accurately to assure a good quality of the treatment and to develop new treatment methods and source configurations. At the Nederland s Meetinstituut (NMi) a project is going on for the development of a primary standard for betadosimetry. With this standard, dose and dose distributions of β-sources as used in brachytherapy can be measured in terms of absorbed dose to water. The primary standard is based on an extrapolation chamber. The extrapolation chamber will become part of a quality assurance system in Dutch hospitals for endovascular brachytherapy sources. The quality assurance system will further consist of transfer standards like well-type ionisation chambers, plastic scintillator systems and radiochromic film dosimetry. Apart from the endovascular sources the extrapolation chamber will be used to characterize ophthalmic applicators

  7. The use of nonlinear regression analysis for integrating pollutant concentration measurements with atmospheric dispersion modeling for source term estimation

    International Nuclear Information System (INIS)

    Edwards, L.L.; Freis, R.P.; Peters, L.G.; Gudiksen, P.H.; Pitovranov, S.E.

    1993-01-01

    The accuracy associated with assessing the environmental consequences of an accidental release of radioactivity is highly dependent on the knowledge of the source term characteristics, which are generally poorly known. The development of an automated numerical technique that integrates the radiological measurements with atmospheric dispersion modeling for more accurate source term estimation is reported. Often, this process of parameter estimation is performed by an emergency response assessor, who takes an intelligent first guess at the model parameters, then, comparing the model results with whatever measurements are available, makes an intuitive, informed next guess of the model parameters. This process may be repeated any number of times until the assessor feels that the model results are reasonable in terms of the measured observations. A new approach, based on a nonlinear least-squares regression scheme coupled with the existing Atmospheric Release Advisory Capability three-dimensional atmospheric dispersion models, is to supplement the assessor's intuition with automated mathematical methods that do not significantly increase the response time of the existing predictive models. The viability of the approach is evaluated by estimation of the known SF 6 tracer release rates associated with the Mesoscale Atmospheric Transport Studies tracer experiments conducted at the Savannah River Laboratory during 1983. These 19 experiments resulted in 14 successful, separate tracer releases with sampling of the tracer plumes along the cross-plume arc situated ∼30 km from the release site

  8. Governance and Citizens' Engagement in Terms of Local Sustainable Development

    Directory of Open Access Journals (Sweden)

    Agnieszka Sobol

    2015-01-01

    Full Text Available Local sustainable development emphasizes the role of a community. One of the key prerequisite of this process is therefore participation of inhabitants. Nevertheless traditional way of managing cities does not work very well in terms of public engagement. Local sustainable development requires both i.e. governance mechanisms introduced by the local authorities and positive reaction of inhabitants for the invitation for cooperation. The paper is intended to explore some critical issues and dimensions of governance and citizens' engagement in terms of local sustainable development. It shows the general outlook on the most relevant conditions, factors, problems and barriers of this process in Poland. It presents experiences of the city of Rybnik in its work towards public engagement in local development.

  9. Applying open source innovation approaches in developing business innovation

    DEFF Research Database (Denmark)

    Aagaard, Annabeth; Lindgren, Peter

    2015-01-01

    and managed effectively in developing business model innovation. The aim of this paper is therefore to close this research gap and to provide new knowledge within the research field of OI and OI applications. Thus, in the present study we explore the facilitation and management of open source innovation...... in developing business model innovation in the context of an international OI contest across five international case companies. The findings reveal six categories of key antecedents in effective facilitation and management of OI in developing business model innovation.......More and more companies are pursuing continuous innovation through different types of open source innovation and across different partners. The growing interest in open innovation (OI) originates both from the academic community as well as amongst practitioners motivating further investigation...

  10. Coping with terms-of-trade shocks in developing countries

    OpenAIRE

    Christian Broda; Cedric Tille

    2003-01-01

    Sharp swings in a developing country's terms of trade, the price of its exports relative to the price of its imports, can seriously disrupt output growth. An analysis of the effects of a decline in export prices in seventy-five developing economies suggests that countries with a flexible exchange rate will experience a much milder contraction in output than their counterparts with fixed exchange rate regimes.

  11. Laser Ion Source Development for ISOL Systems at RIA

    CERN Document Server

    Liu, Yuan; Beene, James R; Bilheux, Hassina Z; Brueck, Kim; Geppert, Christopher; Havener, Charles; Kessler, Thomas; Krause, Herbert F; Schultz, David R; Stracener, Dan; Vane, C R; Wendt, Klaus

    2005-01-01

    The isobaric purity of radioactive ion beams (RIBs) is of crucial importance to many experiments. Laser ion sources based on resonant photoionization have already proved to be of great value at existing ISOL RIB facilities. In these ion sources, ions of a selected isotope are produced by laser radiation via stepwise atomic resonant excitations followed by ionization in the last transition. Because each element has its own unique atomic energy levels, the resonant photoionization process can provide elemental selectivity of nearly 100%. We have initiated a research effort to develop a prototype laser ion source with the potential to achieve the high selectivity and high efficiency required for research with ISOL-generated RIBs at the Rare Isotope Accelerator (RIA). A pilot experiment has been conducted to demonstrate resonant photoionization of three atomic species using all-solid-state tunable Ti:Sapphire lasers. Three Ti:Sapphire lasers were provided by the University of Mainz and used in the experiment for ...

  12. Development of a clockwork light source to enable cervical inspection by village health workers

    Directory of Open Access Journals (Sweden)

    Steventon Richard

    2002-12-01

    Full Text Available Abstract Background Cervical cancer can often be prevented by screening and may be curable if identified and treated in its early stages. However, 80% of new cases occur in less-developed countries where cervical cancer screening programmes are small-scale or non-existent. This is a human tragedy of great proportion, with many of those affected being young mothers. There is some evidence that cancerous or precancerous lesions may be detected by visual inspection with acetic acid (VIA and field studies indicate that this technique is effective, safe and acceptable to women. However, the provision of a light source for inspection of the cervix presents a major problem in less-developed countries, where candles and torches often provide the only means of illumination. Our objective was to develop a light source based on clockwork technology, that required no batteries or external power source. Methods We adapted the design of a commercially available clockwork torch to provide a light source for cervical inspection. The light source was then tested under laboratory conditions in a comparison with other illumination methods typically used in this application. Results The light source gave illuminance levels greater than those produced by any other method tested, and also had considerable advantages in terms of ease of use and safety. Conclusion This design is small, compact, effective and safe to use and promises a better and more affordable means of visualising the cervix. Further field trials of VIA are now required which incorporate this light source.

  13. Development of nuclear design criteria for neutron spallation sources

    Energy Technology Data Exchange (ETDEWEB)

    Sordo, F.; Abanades, A. [E.T.S. Industriales, Madrid Polytechnic University, UPM, J.Gutierrez Abascal, 2 -28006 Madrid (Spain)

    2008-07-01

    Spallation neutron sources allow obtaining high neutronic flux for many scientific and industrial applications. In recent years, several proposals have been made about its use, notably the European Spallation Source (ESS), the Japanese Spallation Source (JSNS) and the projects of Accelerator-Driven Subcritical reactors (ADS), particularly in the framework of EURATOM programs. Given their interest, it seems necessary to establish adequate design basis for guiding the engineering analysis and construction projects of this kind of installations. In this sense, all works done so far seek to obtain particular solutions to a particular design, but there has not been any general development to set up an engineering methodology in this field. In the integral design of a spallation source, all relevant physical processes that may influence its behaviour must be taken into account. Neutronic aspects (emitted neutrons and their spectrum, generation performance..), thermomechanical (energy deposition, cooling conditions, stress distribution..), radiological (spallation waste activity, activation reactions and residual heat) and material properties alteration due to irradiation (atomic displacements and gas generation) must all be considered. After analysing in a systematic manner the different options available in scientific literature, the main objective of this thesis was established as making a significant contribution to determine the limiting factors of the main aspects of spallation sources, its application range and the criteria for choosing optimal materials. To achieve this goal, a series of general simulations have been completed, covering all the relevant physical processes in the neutronic and thermal-mechanical field. Finally, the obtained criteria have been applied to the particular case of the design of the spallation source of subcritical reactors PDX-ADS and XT-ADS. These two designs, developed under the European R and D Framework Program, represent nowadays

  14. Development of nuclear design criteria for neutron spallation sources

    International Nuclear Information System (INIS)

    Sordo, F.; Abanades, A.

    2008-01-01

    Spallation neutron sources allow obtaining high neutronic flux for many scientific and industrial applications. In recent years, several proposals have been made about its use, notably the European Spallation Source (ESS), the Japanese Spallation Source (JSNS) and the projects of Accelerator-Driven Subcritical reactors (ADS), particularly in the framework of EURATOM programs. Given their interest, it seems necessary to establish adequate design basis for guiding the engineering analysis and construction projects of this kind of installations. In this sense, all works done so far seek to obtain particular solutions to a particular design, but there has not been any general development to set up an engineering methodology in this field. In the integral design of a spallation source, all relevant physical processes that may influence its behaviour must be taken into account. Neutronic aspects (emitted neutrons and their spectrum, generation performance..), thermomechanical (energy deposition, cooling conditions, stress distribution..), radiological (spallation waste activity, activation reactions and residual heat) and material properties alteration due to irradiation (atomic displacements and gas generation) must all be considered. After analysing in a systematic manner the different options available in scientific literature, the main objective of this thesis was established as making a significant contribution to determine the limiting factors of the main aspects of spallation sources, its application range and the criteria for choosing optimal materials. To achieve this goal, a series of general simulations have been completed, covering all the relevant physical processes in the neutronic and thermal-mechanical field. Finally, the obtained criteria have been applied to the particular case of the design of the spallation source of subcritical reactors PDX-ADS and XT-ADS. These two designs, developed under the European R and D Framework Program, represent nowadays

  15. SOURCE TERM ESTIMATION BASED on PLANT STATUS and on GAMMA DOSE RATES Measured by an ON-line environmental Monitoring Network

    International Nuclear Information System (INIS)

    Stubna, M.; Bujan, A.; Duranova, T.

    1997-01-01

    A number of severe accident analyses for reactor unit with WWER-440 (213) has been performed in order to evaluate the source term and radiological consequences. As a tool for these analyses the WWER modified version of Source Term Code Package and Real Time Accident Release Consequences codes have been used. A set of emergency procedures - manuals for quick estimation of the source term and countermeasures introduction during early -pre-release phase of severe accident progression has been developed at Nuclear Power Plants Research Institute Trnava, Inc. These manuals are subdivided into three groups: 1.) evaluation of the barriers integrity, 2.) source term estimation and 3.) estimation of the distances for the countermeasures introduction. A methodology and computer module for interpretation of environmental data - source term assessment during post-release phase from on-line environmental network has been developed at Nuclear Power Plants Research Institute Trnava, Inc. The method is based on the conversion of measured dose rates to the source term,i.e. airborne radioactivity release rate, taking into account real meteorological data and location of the measure points. The bootstrap method for the estimation of the mean value of source term Q as integral value of the release and confidence interval of Q has been selected. The methodology of Q distribution into fission product groups according to code Real Time Accident Release Consequences needs is based on known plant status, i.e. on the results of pre calculated accident sequences. The paper describes the methodologies introduced above and the way of their application

  16. Developing a source-receptor methodology for the characterization of VOC sources in ambient air

    International Nuclear Information System (INIS)

    Borbon, A.; Badol, C.; Locoge, N.

    2005-01-01

    Since 2001, in France, a continuous monitoring of about thirty ozone precursor non-methane hydrocarbons (NMHC) is led in some urban areas. The automated system for NMHC monitoring consists of sub-ambient preconcentration on a cooled multi-sorbent trap followed by thermal desorption and bidimensional Gas Chromatography/Flame Ionisation Detection analysis.The great number of data collected and their exploitation should provide a qualitative and quantitative assessment of hydrocarbon sources. This should help in the definition of relevant strategies of emission regulation as stated by the European Directive relative to ozone in ambient air (2002/3/EC). The purpose of this work is to present the bases and the contributions of an original methodology known as source-receptor in the characterization of NMHC sources. It is a statistical and diagnostic approach, adaptable and transposable in all urban sites, which integrates the spatial and temporal dynamics of the emissions. The methods for source identification combine descriptive or more complex complementary approaches: 1) univariate approach through the analysis of NMHC time series and concentration roses, 2) bivariate approach through a Graphical Ratio Analysis and a characterization of scatterplot distributions of hydrocarbon pairs, 3) multivariate approach with Principal Component Analyses on various time basis. A linear regression model is finally developed to estimate the spatial and temporal source contributions. Apart from vehicle exhaust emissions, sources of interest are: combustion and fossil fuel-related activities, petrol and/or solvent evaporation, the double anthropogenic and biogenic origin of isoprene and other industrial activities depending on local parameters. (author)

  17. Chernobyl radiocesium in freshwater fish: Long-term dynamics and sources of variation

    Energy Technology Data Exchange (ETDEWEB)

    Sundbom, M [Uppsala Univ., Dept. of Limnology, Uppsala (Sweden)

    2002-04-01

    The aim of this thesis was to investigate both the long-term temporal pattern and sources of individual variation for radiocesium in freshwater fish. The basis for the study is time series of {sup 137}Cs activity concentrations in fish from three lakes in the area North-west of Uppsala, Sweden that received considerable amounts of {sup 137}Cs from Chernobyl in may 1986. The lakes were Lake Ekholmssjoen, Lake Flatsjoen and Lake Siggeforasjoen, all small forest lakes, but with different morphometrical and chemical characteristics. The data were collected regularly, usually several times per year, during 1986-2000, using consistent methods. More than 7600 fish individuals from 7 species covering wide size ranges and feeding habits were analysed for {sup 137}Cs. For each fish was the length, weight, sex, and often the stomach contend recorded. The evaluation on long-term trends were based on data from all three lakes, while the study on sources of variation evaluated data from Lake Flatsjoen only. (au)

  18. Source terms associated with two severe accident sequences in a 900 MWe PWR

    International Nuclear Information System (INIS)

    Fermandjian, J.; Evrard, J.M.; Berthion, Y.; Lhiaubet, G.; Lucas, M.

    1983-12-01

    Hypothetical accidents taken into account in PWR risk assessment result in fission product release from the fuel, transfer through the primary circuit, transfer into the reactor containment building (RCB) and finally release to the environment. The objective of this paper is to define the characteristics of the source term (noble gases, particles and volatile iodine forms) released from the reactor containment building during two dominant core-melt accident sequences: S 2 CD and TLB according to the ''Reactor Safety Study'' terminology. The reactor chosen for this study is a French 900 MWe PWR unit. The reactor building is a prestressed concrete containment with an internal liner. The first core-melt accident sequence is a 2-break loss-of-coolant accident on the cold leg, with failure of both system and the containment spray system. The second one is a transient initiated by a loss of offsite and onsite power supply and auxiliary feedwater system. These two sequences have been chosen because they are representative of risk dominant scenarios. Source terms associated with hypothetical core-melt accidents S 2 CD and TLB in a French PWR -900 MWe- have been performed using French computer codes (in particular, JERICHO Code for containment response analysis and AEROSOLS/31 for aerosol behavior in the containment)

  19. Source term and behavioural parameters for a postulated HIFAR loss-of-coolant accident

    International Nuclear Information System (INIS)

    May, F.G.

    1987-01-01

    The fraction of the fission product inventory which might be released into the atmosphere of the HIFAR reactor containment building (RCB) during a postulated loss-of-coolant accident (LOCA) has been evaluated as a function of time, for each classification of airborne radioactivity. This appraisal will be used as the source term for a computer program, which uses realistic attenuation of the fission product aerosol in a single compartment model with a defined leakrate to predict possible radioactive releases into the environment in a hypothetical bounding case reactor accident which is rather more severe in all major aspects than any single LOCA. Also given are the parameters governing the attenuation of the aerosol and vapours in the atmosphere of the RCB so that their behaviour may be accurately modelled. The source terms for several other types of accident involving the meltdown of fuel elements have also been considered but in less detail than the LOCA case. In some of the cases, the fission products are released directly to atmosphere, so there is no attenuation of the release by deposition within the RCB

  20. Source terms; isolation and radiological consequences of carbon-14 waste in the Swedish SFR repository

    International Nuclear Information System (INIS)

    Hesboel, R.; Puigdomenech, I.; Evans, S.

    1990-01-01

    The source term, isolation capacity, and long-term radiological exposure of 14 C from the Swedish underground repository for low and intermediate level waste (SFR) is assessed. The prospective amount of 14 C in the repository is assumed to be 5 TBq. Spent ion exchange resins will be the dominant source of 14 C. The pore water in the concrete repository is expected to maintain a pH of >10.5 for a period of at least 10 6 y. The cement matrix of the repository will retain most of the 14 CO 3 2- initially present. Bacterial production of CO 2 and CH 4 from degradation of ion-exchange resins and bitumen may contribute to 14 C release to the biosphere. However, CH 4 contributes only to a small extent to the overall carbon loss from freshwater ecosystems. The individual doses to local and regional individuals peaked with 5x10 -3 and regional individuals peaked with 5x10 -3 and 8x10 -4 μSv y -1 respectively at about 2.4x10 4 years. A total leakage of 8.4 GBq of 14 C from the repository will cause a total collective dose commitment of 1.1 manSv or 130 manSv TBq -1 . (authors)

  1. Projected Source Terms for Potential Sabotage Events Related to Spent Fuel Shipments

    International Nuclear Information System (INIS)

    Luna, R.E.; Neuhauser, K.S.; Vigil, M.G.

    1999-01-01

    Two major studies, one sponsored by the U.S. Department of Energy and the other by the U.S. Nuclear Regulatory Commission, were conducted in the late 1970s and early 1980s to provide information and source terms for an optimally successful act of sabotage on spent fuel casks typical of those available for use. This report applies the results of those studies and additional analysis to derive potential source terms for certain classes of sabotage events on spent fuel casks and spent fuel typical of those which could be shipped in the early decades of the 21st century. In addition to updating the cask and spent fuel characteristics used in the analysis, two release mechanisms not included in the earlier works were identified and evaluated. As would be expected, inclusion of these additional release mechanisms resulted in a somewhat higher total release from the postulated sabotage events. Although health effects from estimated releases were addressed in the earlier study conducted for U.S. Department of Energy, they have not been addressed in this report. The results from this report maybe used to estimate health effects

  2. Chernobyl radiocesium in freshwater fish: Long-term dynamics and sources of variation

    International Nuclear Information System (INIS)

    Sundbom, M.

    2002-01-01

    The aim of this thesis was to investigate both the long-term temporal pattern and sources of individual variation for radiocesium in freshwater fish. The basis for the study is time series of 137 Cs activity concentrations in fish from three lakes in the area North-west of Uppsala, Sweden that received considerable amounts of 137 Cs from Chernobyl in may 1986. The lakes were Lake Ekholmssjoen, Lake Flatsjoen and Lake Siggeforasjoen, all small forest lakes, but with different morphometrical and chemical characteristics. The data were collected regularly, usually several times per year, during 1986-2000, using consistent methods. More than 7600 fish individuals from 7 species covering wide size ranges and feeding habits were analysed for 137 Cs. For each fish was the length, weight, sex, and often the stomach contend recorded. The evaluation on long-term trends were based on data from all three lakes, while the study on sources of variation evaluated data from Lake Flatsjoen only. (au)

  3. Long-term dust aerosol production from natural sources in Iceland.

    Science.gov (United States)

    Dagsson-Waldhauserova, Pavla; Arnalds, Olafur; Olafsson, Haraldur

    2017-02-01

    Iceland is a volcanic island in the North Atlantic Ocean with maritime climate. In spite of moist climate, large areas are with limited vegetation cover where >40% of Iceland is classified with considerable to very severe erosion and 21% of Iceland is volcanic sandy deserts. Not only do natural emissions from these sources influenced by strong winds affect regional air quality in Iceland ("Reykjavik haze"), but dust particles are transported over the Atlantic ocean and Arctic Ocean >1000 km at times. The aim of this paper is to place Icelandic dust production area into international perspective, present long-term frequency of dust storm events in northeast Iceland, and estimate dust aerosol concentrations during reported dust events. Meteorological observations with dust presence codes and related visibility were used to identify the frequency and the long-term changes in dust production in northeast Iceland. There were annually 16.4 days on average with reported dust observations on weather stations within the northeastern erosion area, indicating extreme dust plume activity and erosion within the northeastern deserts, even though the area is covered with snow during the major part of winter. During the 2000s the highest occurrence of dust events in six decades was reported. We have measured saltation and Aeolian transport during dust/volcanic ash storms in Iceland, which give some of the most intense wind erosion events ever measured. Icelandic dust affects the ecosystems over much of Iceland and causes regional haze. It is likely to affect the ecosystems of the oceans around Iceland, and it brings dust that lowers the albedo of the Icelandic glaciers, increasing melt-off due to global warming. The study indicates that Icelandic dust may contribute to the Arctic air pollution. Long-term records of meteorological dust observations from Northeast Iceland indicate the frequency of dust events from Icelandic deserts. The research involves a 60-year period and

  4. Development of the Sixty Watt Heat-Source hardware components

    International Nuclear Information System (INIS)

    McNeil, D.C.; Wyder, W.C.

    1995-01-01

    The Sixty Watt Heat Source is a nonvented heat source designed to provide 60 thermal watts of power. The unit incorporates a plutonium-238 fuel pellet encapsulated in a hot isostatically pressed General Purpose Heat Source (GPHS) iridium clad vent set. A molybdenum liner sleeve and support components isolate the fueled iridium clad from the T-111 strength member. This strength member serves as the pressure vessel and fulfills the impact and hydrostatic strength requirements. The shell is manufactured from Hastelloy S which prevents the internal components from being oxidized. Conventional drawing operations were used to simplify processing and utilize existing equipment. The deep drawing reqirements for the molybdenum, T-111, and Hastelloy S were developed from past heat source hardware fabrication experiences. This resulted in multiple step drawing processes with intermediate heat treatments between forming steps. The molybdenum processing included warm forming operations. This paper describes the fabrication of these components and the multiple draw tooling developed to produce hardware to the desired specifications. copyright 1995 American Institute of Physics

  5. A simplified approach to estimating reference source terms for LWR designs

    International Nuclear Information System (INIS)

    1999-12-01

    systems. The publication of this IAEA technical document represents the conclusion of a task, initiated in 1996, devoted to the estimation of the radioactive source term in nuclear reactors. It focuses mainly on light water reactors (LWRs)

  6. Challenges in defining a radiologic and hydrologic source term for underground nuclear test centers, Nevada Test Site, Nye County, Nevada

    International Nuclear Information System (INIS)

    Smith, D.K.

    1995-06-01

    The compilation of a radionuclide inventory for long-lived radioactive contaminants residual from nuclear testing provides a partial measure of the radiologic source term at the Nevada Test Site. The radiologic source term also includes potentially mobile short-lived radionuclides excluded from the inventory. The radiologic source term for tritium is known with accuracy and is equivalent to the hydrologic source term within the saturated zone. Definition of the total hydrologic source term for fission and activation products that have high activities for decades following underground testing involves knowledge and assumptions which are presently unavailable. Systematic investigation of the behavior of fission products, activation products and actinides under saturated or Partially saturated conditions is imperative to define a representative total hydrologic source term. This is particularly important given the heterogeneous distribution of radionuclides within testing centers. Data quality objectives which emphasize a combination of measurements and credible estimates of the hydrologic source term are a priority for near-field investigations at the Nevada Test Site

  7. Toward a Mechanistic Source Term in Advanced Reactors: A Review of Past U.S. SFR Incidents, Experiments, and Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Bucknor, Matthew; Brunett, Acacia J.; Grabaskas, David

    2016-04-17

    In 2015, as part of a Regulatory Technology Development Plan (RTDP) effort for sodium-cooled fast reactors (SFRs), Argonne National Laboratory investigated the current state of knowledge of source term development for a metal-fueled, pool-type SFR. This paper provides a summary of past domestic metal-fueled SFR incidents and experiments and highlights information relevant to source term estimations that were gathered as part of the RTDP effort. The incidents described in this paper include fuel pin failures at the Sodium Reactor Experiment (SRE) facility in July of 1959, the Fermi I meltdown that occurred in October of 1966, and the repeated melting of a fuel element within an experimental capsule at the Experimental Breeder Reactor II (EBR-II) from November 1967 to May 1968. The experiments described in this paper include the Run-Beyond-Cladding-Breach tests that were performed at EBR-II in 1985 and a series of severe transient overpower tests conducted at the Transient Reactor Test Facility (TREAT) in the mid-1980s.

  8. Evaluation of severe accident risks: Methodology for the containment, source term, consequence, and risk integration analyses. Volume 1, Revision 1

    International Nuclear Information System (INIS)

    Gorham, E.D.; Breeding, R.J.; Brown, T.D.; Harper, F.T.; Helton, J.C.; Murfin, W.B.; Hora, S.C.

    1993-12-01

    NUREG-1150 examines the risk to the public from five nuclear power plants. The NUREG-1150 plant studies are Level III probabilistic risk assessments (PRAs) and, as such, they consist of four analysis components: accident frequency analysis, accident progression analysis, source term analysis, and consequence analysis. This volume summarizes the methods utilized in performing the last three components and the assembly of these analyses into an overall risk assessment. The NUREG-1150 analysis approach is based on the following ideas: (1) general and relatively fast-running models for the individual analysis components, (2) well-defined interfaces between the individual analysis components, (3) use of Monte Carlo techniques together with an efficient sampling procedure to propagate uncertainties, (4) use of expert panels to develop distributions for important phenomenological issues, and (5) automation of the overall analysis. Many features of the new analysis procedures were adopted to facilitate a comprehensive treatment of uncertainty in the complete risk analysis. Uncertainties in the accident frequency, accident progression and source term analyses were included in the overall uncertainty assessment. The uncertainties in the consequence analysis were not included in this assessment. A large effort was devoted to the development of procedures for obtaining expert opinion and the execution of these procedures to quantify parameters and phenomena for which there is large uncertainty and divergent opinions in the reactor safety community

  9. [Effect of anemia on child development: long-term consequences].

    Science.gov (United States)

    Zavaleta, Nelly; Astete-Robilliard, Laura

    2017-01-01

    Anemia in children younger than 3 years is a public health problem in Peru and worldwide. It is believed that one of the primary causes of anemia is iron deficiency. Numerous studies and reviews have reported that iron deficiency limited psychomotor development in children and that, despite the correction of anemia, children with iron deficiency experienced poorer long-term performance in cognitive, social, and emotional functioning. These outcomes were reported in observational studies, follow-up studies, and experimental studies with a control group. Anemia can decrease school performance, productivity in adult life, quality of life, and the general income of affected individuals. Here we describe possible mechanisms underlying the effect of iron deficiency, with or without anemia, on childhood development. The high rate of anemia in this age group is a cause for concern. Moreover, anemia should be prevented in the first year of life to avoid long-term negative effects on individual development.

  10. Environmental radiation safety: source term modification by soil aerosols. Interim report

    International Nuclear Information System (INIS)

    Moss, O.R.; Allen, M.D.; Rossignol, E.J.; Cannon, W.C.

    1980-08-01

    The goal of this project is to provide information useful in estimating hazards related to the use of a pure refractory oxide of 238 Pu as a power source in some of the space vehicles to be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere, and to impact with the earth's surface without releasing any plutonium, the possibility that such an event might produce aerosols composed of soil and 238 PuO 2 cannot be absolutely excluded. This report presents the results of our most recent efforts to measure the degree to which the plutonium aerosol source term might be modified in a terrestrial environment. The five experiments described represent our best effort to use the original experimental design to study the change in the size distribution and concentration of a 238 PuO 2 aerosol due to coagulation with an aerosol of clay or sandy loam soil

  11. Development open source microcontroller based temperature data logger

    Science.gov (United States)

    Abdullah, M. H.; Che Ghani, S. A.; Zaulkafilai, Z.; Tajuddin, S. N.

    2017-10-01

    This article discusses the development stages in designing, prototyping, testing and deploying a portable open source microcontroller based temperature data logger for use in rough industrial environment. The 5V powered prototype of data logger is equipped with open source Arduino microcontroller for integrating multiple thermocouple sensors with their module, secure digital (SD) card storage, liquid crystal display (LCD), real time clock and electronic enclosure made of acrylic. The program for the function of the datalogger is programmed so that 8 readings from the thermocouples can be acquired within 3 s interval and displayed on the LCD simultaneously. The recorded temperature readings at four different points on both hydrodistillation show similar profile pattern and highest yield of extracted oil was achieved on hydrodistillation 2 at 0.004%. From the obtained results, this study achieved the objective of developing an inexpensive, portable and robust eight channels temperature measuring module with capabilities to monitor and store real time data.

  12. Open Source Power Plant Simulator Development Under Matlab Environment

    International Nuclear Information System (INIS)

    Ratemi, W.M.; Fadilah, S.M.; Abonoor, N

    2008-01-01

    In this paper an open source programming approach is targeted for the development of power plant simulator under Matlab environment. With this approach many individuals can contribute to the development of the simulator by developing different orders of complexities of the power plant components. Such modules can be modeled based on physical principles, or using neural networks or other methods. All of these modules are categorized in Matlab library, of which the user can select and build up his simulator. Many international companies developed its own authoring tool for the development of its simulators, and hence it became its own property available for high costs. Matlab is a general software developed by mathworks that can be used with its toolkits as the authoring tool for the development of components by different individuals, and through the appropriate coordination, different plant simulators, nuclear, traditional , or even research reactors can be computerly assembled. In this paper, power plant components such as a pressurizer, a reactor, a steam generator, a turbine, a condenser, a feedwater heater, a valve, a pump are modeled based on physical principles. Also a prototype modeling of a reactor ( a scram case) based on neural networks is developed. These modules are inserted in two different Matlab libraries one called physical and the other is called neural. Furthermore, during the simulation one can pause and shuffle the modules selected from the two libraries and then proceed the simulation. Also, under the Matlab environment a PID controller is developed for multi-loop plant which can be integrated for the control of the appropriate developed simulator. This paper is an attempt to base the open source approach for the development of power plant simulators or even research reactor simulators. It then requires the coordination among interested individuals or institutions to set it to professionalism. (author)

  13. Ion source developments for RNB production at Spiral / GANIL

    International Nuclear Information System (INIS)

    Villari, A.C.C.; Barue, C.; Gaubert, G.; Gibouin, S.; Huguet, Y.; Jardin, P.; Kandri-Rody, S.; Landre-Pellemoine, F.; Lecesne, N.; Leroy, R.; Lewitowicz, M.; Marry, C.; Maunoury, L.; Pacquet, J.Y.; Rataud, J.P.; Saint-Laurent, M.G.; Stodel, C.; Lichtenthaeler, R.; Angelique, J.C.; Orr, N.A.

    2000-01-01

    The first on-line production system for SPIRAL/GANIL (Radioactive Ion Production System with Acceleration on-Line) phase-I has been commissioned on the SIRa (Radioactive Ion Separator) test bench. Exotic multicharged noble gas ion beams have been obtained during several days. In parallel, a new ECRIS (Electron Cyclotron Resonance Ion Source) for mono-charged ions has also been developed. Preliminary, off-line results are presented. (authors)

  14. Smartphone Applications - Idea sourcing, and app development: Implications for firms

    Directory of Open Access Journals (Sweden)

    Debbie Vigar-Ellis

    2014-05-01

    Full Text Available With the dramatic increase in smartphone usage and the consequent increase in applications (apps for these smartphones, organisations are constantly looking for new apps to offer customers as well as employees.  Information Systems (IS departments of organisations have traditionally been tasked with the acquisition and/or development of such information technologies within organisations.  This research aimed to determine from IS managers, the smartphone app usage in firms, the sources of app ideas and the locations for app development.  It also investigated various aspects of the success or otherwise of the development process.  Results indicate that while most ideas for apps currently come from IS and marketing departments within the organisation, and development of apps is also done mainly within the organisation , these development strategies are not necessarily the most effective.  Managerial implications are discussed.

  15. Development of Electricity Generation from Renewable Energy Sources in Turkey

    Science.gov (United States)

    Kentel, E.

    2011-12-01

    Electricity is mainly produced from coal, natural gas and hydropower in Turkey. However, almost all the natural gas and high quality coal are imported. Thus, increasing the shares of both hydro and other renewables in energy supply is necessary to decrease dependency of the country on foreign sources. In 2008, the total installed capacity of Turkey was around 42000 MW and 66 % of this was from thermal sources. The remaining 33 % was from hydro, which leaves only one percent for the other renewable energy sources. The share of renewable energy in the energy budget of Turkey has increased in the last two decades; however, in 2008, only 17 % of the total electricity generation was realized from renewable sources most of which was hydro. According to State Hydraulic Works (SHW) which is the primary executive state agency responsible for the planning, operating and managing of Turkey's water resources, Turkey utilizes only around 35% of its economically viable hydro potential. The current situation clearly demonstrates the need for increasing the share of renewables in the energy budget. New laws, such as the Electricity Market Law, have been enacted and the following items were identified by the Ministry of Energy and Natural Resources of Turkey among primary energy policies and priorities: (i) decreasing dependency on foreign resources by prioritizing utilization of natural resources, (ii) increasing the share of renewable energy resources in the energy budget of Turkey; (iii) minimization of adverse environmental impacts of production and utilization of natural resources. The government's energy policy increased investments in renewable energy resources; however lack of a needed legal framework brought various environmental and social problems with this fast development. The development of the share of renewable resources in the energy budget, current government policy, and environmental concerns related with renewables, and ideas to improve the overall benefits of

  16. Spallation neutron source target station design, development, and commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Haines, J.R., E-mail: hainesjr@ornl.gov; McManamy, T.J.; Gabriel, T.A.; Battle, R.E.; Chipley, K.K.; Crabtree, J.A.; Jacobs, L.L.; Lousteau, D.C.; Rennich, M.J.; Riemer, B.W.

    2014-11-11

    The spallation neutron source target station is designed to safely, reliably, and efficiently convert a 1 GeV beam of protons to a high flux of about 1 meV neutrons that are available at 24 neutron scattering instrument beam lines. Research and development findings, design requirements, design description, initial checkout testing, and results from early operation with beam are discussed for each of the primary target subsystems, including the mercury target, neutron moderators and reflector, surrounding vessels and shielding, utilities, remote handling equipment, and instrumentation and controls. Future plans for the mercury target development program are also briefly discussed.

  17. A Stigmergy Approach for Open Source Software Developer Community Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Beaver, Justin M [ORNL; Potok, Thomas E [ORNL; Pullum, Laura L [ORNL; Treadwell, Jim N [ORNL

    2009-01-01

    The stigmergy collaboration approach provides a hypothesized explanation about how online groups work together. In this research, we presented a stigmergy approach for building an agent based open source software (OSS) developer community collaboration simulation. We used group of actors who collaborate on OSS projects as our frame of reference and investigated how the choices actors make in contribution their work on the projects determinate the global status of the whole OSS projects. In our simulation, the forum posts and project codes served as the digital pheromone and the modified Pierre-Paul Grasse pheromone model is used for computing developer agent behaviors selection probability.

  18. Developing electron beam bunching technology for improving light sources

    International Nuclear Information System (INIS)

    Carlsten, B.E.; Chan, K.C.D.; Feldman, D.W.

    1997-01-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to develop a new electron bunch compression technology, experimentally demonstrate subpicosecond compression of bunches with charges on the order of 1 nC, and to theoretically investigate fundamental limitations to electron bunch compression. All of these goals were achieved, and in addition, the compression system built for this project was used to generate 22 nm light in a plasma-radiator light source

  19. Development of alternative/renewable sources of energy in Pakistan

    International Nuclear Information System (INIS)

    Sharif, M.

    2005-01-01

    The depleting Conventional Energy Resources and highly raised prices of fuel oil, coal, firewood and such other fossil fuels, have forced the mankind to think about the utilization of Alternative / Renewable Sources of Energy. Alternative / Renewable Energy is very attractive, reliable and cost competitive energy. Sun is readily available to provide a clean, abundant and virtually infinite energy to meet the significant portion of mankind's energy-needs. The possible use of renewable-energy sources is discussed in this paper, in order to fill the estimated gap between the available energy-sources and energy-needs of our country in the near future. Designing, Fabrication and Installation of different renewable-energy devices by PCSIR are also discussed in this paper. Different renewable-energy devices such as, solar water heaters, solar cookers, solar dehydrators, solar water-desalination plants, solar heating and cooling of buildings, solar operated absorption-type chiller, solar furnace, solar architecture, developed by PCSIR are discussed in some detail so that the role of renewable-energy sources for their direct use (as heat and power) can be determined. Various technical aspects are discussed to reduce the unit cost with improved efficiency. (author)

  20. Development of Compton gamma-ray sources at LLNL

    Energy Technology Data Exchange (ETDEWEB)

    Albert, F.; Anderson, S. G.; Ebbers, C. A.; Gibson, D. J.; Hartemann, F. V.; Marsh, R. A.; Messerly, M. J.; Prantil, M. A.; Wu, S.; Barty, C. P. J. [Lawrence Livermore National Laboratory, NIF and Photon Science, 7000 East avenue, Livermore, CA 94550 (United States)

    2012-12-21

    Compact Compton scattering gamma-ray sources offer the potential of studying nuclear photonics with new tools. The optimization of such sources depends on the final application, but generally requires maximizing the spectral density (photons/eV) of the gamma-ray beam while simultaneously reducing the overall bandwidth on target to minimize noise. We have developed an advanced design for one such system, comprising the RF drive, photoinjector, accelerator, and electron-generating and electron-scattering laser systems. This system uses a 120 Hz, 250 pC, 2 ps, 0.35 mm mrad electron beam with 250 MeV maximum energy in an X-band accelerator scattering off a 150 mJ, 10 ps, 532 nm laser to generate 5 Multiplication-Sign 10{sup 10} photons/eV/s/Sr at 0.5 MeV with an overall bandwidth of less than 1%. The source will be able to produce photons up to energies of 2.5 MeV. We also discuss Compton scattering gamma-ray source predictions given by numerical codes.

  1. Development of high current low energy H+ ion source

    International Nuclear Information System (INIS)

    Forrester, A.T.; Crow, J.T.; Goebel, D.M.

    1978-01-01

    The ultimate goal of this work is the development of an ion source suitable for double charge exchange of D + ions to D - ions in cesium or other vapor. Since the fraction of the D + which changes to D - may be as high as 0.35 in the energy below one keV, the process appears very favorable. What is desired is a source of several hundred cm 2 area, with a D + current density greater than, say 0.2A/cm 2 . Small angular spread is essential with up to about 0.1 radian being acceptable. A simple approach to this problem appears to be through fine mesh extraction electrodes. In this system a single grid facing the ion source plasma constitutes the entire extraction electrode system. If the potential difference between the grid and the source plasma is large compared to the ion energy at the plasma boundary, then the distance s 0 is just the Child-Langmuir distance corresponding to the ion current density J and the potential difference V 0 between the plasma and the grid

  2. Patterns and sources of personality development in old age.

    Science.gov (United States)

    Kandler, Christian; Kornadt, Anna E; Hagemeyer, Birk; Neyer, Franz J

    2015-07-01

    Despite abundant evidence that personality development continues in adulthood, little is known about the patterns and sources of personality development in old age. We thus investigated mean-level trends and individual differences in change as well as the genetic and environmental sources of rank-order continuity and change in several personality traits (neuroticism, extraversion, openness, agreeableness, conscientiousness, perceived control, and affect intensity) and well-being. In addition, we analyzed the interrelation between perceived control and change in other personality traits as well as between change in personality traits and change in well-being. We analyzed data from older adult twins, aged 64-85 years at Time 1 (N = 410; 135 males and 275 females; 134 monozygotic and 63 dizygotic twin pairs), collected at 2 different time points about 5 years apart. On average, neuroticism increased, whereas extraversion, conscientiousness, and perceived control significantly decreased over time. Change in perceived control was associated with change in neuroticism and conscientiousness, pointing to particular adaptation mechanisms specific to old age. Whereas individual differences in personality traits were fairly stable due to both genetic and environmental sources, individual differences in change were primarily due to environmental sources (beyond random error) indicating plasticity in old age. Even though the average level of well-being did not significantly change over time, individual well-being tended to decrease with strongly increasing levels of neuroticism as well as decreasing extraversion, conscientiousness, and perceived control, indicating that personality traits predict well-being but not vice versa. We discuss implications for theory on personality development across the lifespan. (c) 2015 APA, all rights reserved).

  3. A note on variational multiscale methods for high-contrast heterogeneous porous media flows with rough source terms

    KAUST Repository

    Calo, Victor M.

    2011-09-01

    In this short note, we discuss variational multiscale methods for solving porous media flows in high-contrast heterogeneous media with rough source terms. Our objective is to separate, as much as possible, subgrid effects induced by the media properties from those due to heterogeneous source terms. For this reason, enriched coarse spaces designed for high-contrast multiscale problems are used to represent the effects of heterogeneities of the media. Furthermore, rough source terms are captured via auxiliary correction equations that appear in the formulation of variational multiscale methods [23]. These auxiliary equations are localized and one can use additive or multiplicative constructions for the subgrid corrections as discussed in the current paper. Our preliminary numerical results show that one can capture the effects due to both spatial heterogeneities in the coefficients (such as permeability field) and source terms (e.g., due to singular well terms) in one iteration. We test the cases for both smooth source terms and rough source terms and show that with the multiplicative correction, the numerical approximations are more accurate compared to the additive correction. © 2010 Elsevier Ltd.

  4. A novel integrated approach for the hazardous radioactive dust source terms estimation in future nuclear fusion power plants.

    Science.gov (United States)

    Poggi, L A; Malizia, A; Ciparisse, J F; Gaudio, P

    2016-10-01

    An open issue still under investigation by several international entities working on the safety and security field for the foreseen nuclear fusion reactors is the estimation of source terms that are a hazard for the operators and public, and for the machine itself in terms of efficiency and integrity in case of severe accident scenarios. Source term estimation is a crucial key safety issue to be addressed in the future reactors safety assessments, and the estimates available at the time are not sufficiently satisfactory. The lack of neutronic data along with the insufficiently accurate methodologies used until now, calls for an integrated methodology for source term estimation that can provide predictions with an adequate accuracy. This work proposes a complete methodology to estimate dust source terms starting from a broad information gathering. The wide number of parameters that can influence dust source term production is reduced with statistical tools using a combination of screening, sensitivity analysis, and uncertainty analysis. Finally, a preliminary and simplified methodology for dust source term production prediction for future devices is presented.

  5. New Developments in Long-Term Downhole Monitoring Arrays

    Directory of Open Access Journals (Sweden)

    Jochem Kück

    2006-03-01

    Full Text Available The long-term observation of active geological processes is a major research goal in an increasing number of scientific drilling projects. An extended monitoring phase within a potentially hostile environment (e.g., temperature, pressure, salinity requires new long-lasting and robust instrumentation currently unavailable from either industry or academia. Extended exposure of instrument packages to extreme conditions will typically cause seals to weaken and fail,electronic parts to break under permanent load, and sensors to degrade or develop strong drift. In the framework of scientific exploration, there are currently several major research projects targeting fault zone drilling and in situ measurements to monitor physical and chemical conditions before, during, and after seismic events. Planning has now begun for tool development, testing, and continuous long-term monitoring for the San Andreas Fault Zone Observatory at Depth, SAFOD (Parkfi eld, Calif., U.S.A.; See article on page 32..

  6. The Dietary Composition and Source of Macronutrients Determine Obesity Development

    DEFF Research Database (Denmark)

    Myrmel, Lene Secher

    The drastic worldwide increase in obesity during the last decades is accompanied with several different health disorders. The underlying mechanisms for this escalation is not clear, but certain alterations in the dietary macronutrient composition are suggested to be of importance. In addition...... fat and marine oils. To further investigate the importance of the macronutrient composition on obesity development, we have performed a series of mice experiments. Our results demonstrate that both the amount and source of macronutrients influence obesity development and related disorders. The anti...... to attenuate obesity development. The gut microbiota is less affected by alterations in protein:carbohydrate ratio and adiposity, but is altered in response to an elevated fat intake. The macronutrient composition is able to affect obesity development through direct influence on energy consuming metabolic...

  7. Terms of trade and exchange rate regimes in developing countries

    OpenAIRE

    Christian Broda

    2002-01-01

    Since Friedman (1953), an advantage often attributed to flexible exchange rate regimes over fixed regimes is their ability to insulate more effectively the economy against real shocks. I use a post-Bretton Woods sample (1973-96) of seventy-five developing countries to assess whether the responses of real GDP, real exchange rates, and prices to terms-of-trade shocks differ systematically across exchange rate regimes. I find that responses are significantly different across regimes in a way tha...

  8. The Development of Rehearsal in Verbal Short-Term Memory

    OpenAIRE

    Jarrold, Christopher; Hall, Debbora

    2013-01-01

    Verbal short-term memory, as indexed by immediate serial recall tasks (in which participants must recall several stimuli in order, immediately after presentation), develops considerably across middle childhood. One explanation for this age-related change is that children's ability to rehearse verbal material increases during this period, and one particularly influential version of this account is that only older children engage in any form of rehearsal. In this article, we critique evidence t...

  9. Evaluation of the Non-Transient Hydrologic Source Term from the CAMBRIC Underground Nuclear Test in Frenchman Flat, Nevada Test Site

    International Nuclear Information System (INIS)

    Tompson, A B; Maxwell, R M; Carle, S F; Zavarin, M; Pawloski, G A.; Shumaker, D E

    2005-01-01

    Hydrologic Source Term (HST) calculations completed in 1998 at the CAMBRIC underground nuclear test site were LLNL's first attempt to simulate a hydrologic source term at the NTS by linking groundwater flow and transport modeling with geochemical modeling (Tompson et al., 1999). Significant effort was applied to develop a framework that modeled in detail the flow regime and captured all appropriate chemical processes that occurred over time. However, portions of the calculations were simplified because of data limitations and a perceived need for generalization of the results. For example: (1) Transient effects arising from a 16 years of pumping at the site for a radionuclide migration study were not incorporated. (2) Radionuclide fluxes across the water table, as derived from infiltration from a ditch to which pumping effluent was discharged, were not addressed. (3) Hydrothermal effects arising from residual heat of the test were not considered. (4) Background data on the ambient groundwater flow direction were uncertain and not represented. (5) Unclassified information on the Radiologic Source Term (RST) inventory, as tabulated recently by Bowen et al. (2001), was unavailable; instead, only a limited set of derived data were available (see Tompson et al., 1999). (6) Only a small number of radionuclides and geochemical reactions were incorporated in the work. (7) Data and interpretation of the RNM-2S multiple well aquifer test (MWAT) were not available. As a result, the current Transient CAMBRIC Hydrologic Source Term project was initiated as part of a broader Phase 2 Frenchman Flat CAU flow and transport modeling effort. The source term will be calculated under two scenarios: (1) A more specific representation of the transient flow and radionuclide release behavior at the site, reflecting the influence of the background hydraulic gradient, residual test heat, pumping experiment, and ditch recharge, and taking into account improved data sources and modeling

  10. Heat source component development program, October 1977--February 1978

    International Nuclear Information System (INIS)

    1978-03-01

    The General Purpose Heat Source (GPHS) is being developed by Los Alamos Scientific Laboratory (LASL) for the Department of Energy (DOE) Division of Nuclear Research and Application (DNRA). The first mission scheduled for the GPHS is the NASA Out-of-Ecliptic Flight in January, 1983. During the current reporting period (October--December, 1977, January--February, 1978), activities in this task were conducted as follows: (1) documentation of results of the reentry thermal, ablation, and thermal stress analyses of the conceptual designs; (2) identification and completion of modifications to the thermal and ablation models used to determine the performance response of the heat source modules during reentry; (3) initiation of modifications to the thermal stress model used to determine the performance response of heat source modules during reentry; (4) completion and documentation of the surface chemistry experiments; (5) initiation and completion of activities in support of LASL to define test plans for the trial design phase of the GPHS development program; (6) participation in the GPHS design review meeting held at DOE/Germantown, Maryland, December 19--20, 1977; and (7) initiation of the thermal analysis of Trial Design 1.1

  11. Optogenetic long-term manipulation of behavior and animal development.

    Directory of Open Access Journals (Sweden)

    Christian Schultheis

    Full Text Available Channelrhodopsin-2 (ChR2 is widely used for rapid photodepolarization of neurons, yet, as it requires high-intensity blue light for activation, it is not suited for long-term in vivo applications, e.g. for manipulations of behavior, or photoactivation of neurons during development. We used "slow" ChR2 variants with mutations in the C128 residue, that exhibit delayed off-kinetics and increased light sensitivity in Caenorhabditis elegans. Following a 1 s light pulse, we could photodepolarize neurons and muscles for minutes (and with repeated brief stimulation, up to days with low-intensity light. Photoactivation of ChR2(C128S in command interneurons elicited long-lasting alterations in locomotion. Finally, we could optically induce profound changes in animal development: Long-term photoactivation of ASJ neurons, which regulate larval growth, bypassed the constitutive entry into the "dauer" larval state in daf-11 mutants. These lack a guanylyl cyclase, which possibly renders ASJ neurons hyperpolarized. Furthermore, photostimulated ASJ neurons could acutely trigger dauer-exit. Thus, slow ChR2s can be employed to long-term photoactivate behavior and to trigger alternative animal development.

  12. Novel Slope Source Term Treatment for Preservation of Quiescent Steady States in Shallow Water Flows

    Directory of Open Access Journals (Sweden)

    Khawar Rehman

    2016-10-01

    Full Text Available This paper proposes a robust method for modeling shallow-water flows and near shore tsunami propagation, applicable for both simple and complex geometries with uneven beds. The novel aspect of the model includes the introduction of a new method for slope source terms treatment to preserve quiescent equilibrium over uneven topographies, applicable to both structured and unstructured mesh systems with equal accuracy. Our model is based on the Godunov-type finite volume numerical approximation. Second-order spatial and temporal accuracy is achieved through high resolution gradient reconstruction and the predictor-corrector method, respectively. The approximate Riemann solver of Harten, Lax, and van Leer with contact wave restoration (HLLC is used to compute fluxes. Comparisons of the model’s results with analytical, experimental, and published numerical solutions show that the proposed method is capable of accurately predicting experimental and real-time tsunami propagation/inundation, and dam-break flows over varying topographies.

  13. A Mechanistic Source Term Calculation for a Metal Fuel Sodium Fast Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Grabaskas, David; Bucknor, Matthew; Jerden, James

    2017-06-26

    A mechanistic source term (MST) calculation attempts to realistically assess the transport and release of radionuclides from a reactor system to the environment during a specific accident sequence. The U.S. Nuclear Regulatory Commission (NRC) has repeatedly stated its expectation that advanced reactor vendors will utilize an MST during the U.S. reactor licensing process. As part of a project to examine possible impediments to sodium fast reactor (SFR) licensing in the U.S., an analysis was conducted regarding the current capabilities to perform an MST for a metal fuel SFR. The purpose of the project was to identify and prioritize any gaps in current computational tools, and the associated database, for the accurate assessment of an MST. The results of the study demonstrate that an SFR MST is possible with current tools and data, but several gaps exist that may lead to possibly unacceptable levels of uncertainty, depending on the goals of the MST analysis.

  14. Distributed source term analysis, a new approach to nuclear material inventory verification

    CERN Document Server

    Beddingfield, D H

    2002-01-01

    The Distributed Source-Term Analysis (DSTA) technique is a new approach to measuring in-process material holdup that is a significant departure from traditional hold-up measurement methodology. The DSTA method is a means of determining the mass of nuclear material within a large, diffuse, volume using passive neutron counting. The DSTA method is a more efficient approach than traditional methods of holdup measurement and inventory verification. The time spent in performing DSTA measurement and analysis is a fraction of that required by traditional techniques. The error ascribed to a DSTA survey result is generally less than that from traditional methods. Also, the negative bias ascribed to gamma-ray methods is greatly diminished because the DSTA method uses neutrons which are more penetrating than gamma-rays.

  15. Distributed source term analysis, a new approach to nuclear material inventory verification

    International Nuclear Information System (INIS)

    Beddingfield, D.H.; Menlove, H.O.

    2002-01-01

    The Distributed Source-Term Analysis (DSTA) technique is a new approach to measuring in-process material holdup that is a significant departure from traditional hold-up measurement methodology. The DSTA method is a means of determining the mass of nuclear material within a large, diffuse, volume using passive neutron counting. The DSTA method is a more efficient approach than traditional methods of holdup measurement and inventory verification. The time spent in performing DSTA measurement and analysis is a fraction of that required by traditional techniques. The error ascribed to a DSTA survey result is generally less than that from traditional methods. Also, the negative bias ascribed to γ-ray methods is greatly diminished because the DSTA method uses neutrons which are more penetrating than γ-rays

  16. Methods to prevent the source term of methyl lodide during a core melt accident

    Energy Technology Data Exchange (ETDEWEB)

    Karhu, A. [VTT Energy (Finland)

    1999-11-01

    The purpose of this literature review is to gather available information of the methods to prevent a source term of methyl iodide during a core melt accident. The most widely studied methods for nuclear power plants include the impregnated carbon filters and alkaline additives and sprays. It is indicated that some deficiencies of these methods may emerge. More reactive impregnants and additives could make a great improvement. As a new method in the field of nuclear applications, the potential of transition metals to decompose methyl iodide, is introduced in this review. This area would require an additional research, which could elucidate the remaining questions of the reactions. The ionization of the gaseous methyl iodide by corona-discharge reactors is also shortly described. (au)

  17. Nuclear reaction models - source term estimation for safety design in accelerators

    International Nuclear Information System (INIS)

    Nandy, Maitreyee

    2013-01-01

    Accelerator driven subcritical system (ADSS) employs proton induced spallation reaction at a few GeV. Safety design of these systems involves source term estimation in two steps - multiple fragmentation of the target and n+γ emission through a fast process followed by statistical decay of the primary fragments. The prompt radiation field is estimated in the framework of quantum molecular dynamics (QMD) theory, intra-nuclear cascade or Monte Carlo calculations. A few nuclear reaction model codes used for this purpose are QMD, JQMD, Bertini, INCL4, PHITS, followed by statistical decay codes like ABLA, GEM, GEMINI, etc. In the case of electron accelerators photons and photoneutrons dominate the prompt radiation field. High energy photon yield through Bremsstrahlung is estimated in the framework of Born approximation while photoneutron production is calculated using giant dipole resonance and quasi-deuteron formation cross section. In this talk hybrid and exciton PEQ models and QMD formalism will be discussed briefly

  18. Improved thermal source term generation capability for use in performance assessment and system studies

    International Nuclear Information System (INIS)

    King, J.; Rhodes, C.

    1994-01-01

    This paper describes work performed by the Civilian Radioactive Waste Management System (CRWMS) Management and Operating (M ampersand O) Contractor to improve spent nuclear fuel (SNF) waste stream characterization for system studies. It discusses how these new capabilities may be exploited for thermal source term generation for use in repository performance assessment modeling. SNF historical discharges have been exhaustively tracked, and significant effort has gone into capturing, verifying, and electronically managing spent fuel inventory data. Future discharge projections are produced annually by the Energy Information Administration (EIA) using sophisticated computer models. The output of these models is coupled with annually updated SNF historical discharges to produce what is referred to as the open-quotes reactor database.close quotes This database and related data are published in a variety of ways including on magnetic media for consistent use by analysts or other interested parties

  19. SOURCE 1ST 2.0: development and beta testing

    International Nuclear Information System (INIS)

    Barber, D.H.; Iglesias, F.C.; Hoang, Y.; Dickson, L.W.; Dickson, R.S.; Richards, M.J.; Gibb, R.A.

    1999-01-01

    SOURCE 1ST 2.0 is the Industry Standard fission product release code that is being developed by Ontario Power Generation, New Brunswick Power, Hydro-Quebec, and Atomic Energy of Canada Ltd. This paper is a report on recent progress on requirement specification, code development, and module verification and validation activities. The theoretical basis for each model in the code is described in a module Software Theory Manual. The development of SOURCE IST 2.0 has required code design decisions about how to implement the software requirements. Development and module testing of the β1 release of SOURCE IST 2.0 (released in July 1999) have led to some interesting insights into fission product release modelling. The beta testing process has allowed code developers and analysts to refine the software requirements for the code. The need to verify physical reference data has guided some decisions on the code and data structure design. Examples of these design decisions are provided. Module testing, and verification and validation activities are discussed. These activities include code-targeted testing, stress testing, code inspection, comparison of code with requirements, and comparison of code results with independent algebraic, numerical, or semi-algebraic calculations. The list of isotopes to be modelled by SOURCE IST 2.0 provides an example of a subset of a reference data set. Isotopes are present on the list for a variety of reasons: personnel or public dose, equipment dose (for environmental qualification), fission rate and actinide modelling, or stable (or long-lived) targets for activation processes. To accommodate controlled changes to the isotope list, the isotope list and associated nuclear data are contained in a reference data file. The questions of multiple computing platforms, and of Year 2000 compliance have been addressed by programming rules for the code. By developing and testing modules on most of the different platforms on which the code is intended

  20. Design development of bellows for the DNB beam source

    International Nuclear Information System (INIS)

    Singh, Dhananjay Kumar; Venkata Nagaraju, M.; Joshi, Jaydeep; Patel, Hitesh; Yadav, Ashish; Pillai, Suraj; Singh, Mahendrajit; Bandyopadhyay, Mainak; Chakraborty, A.K.; Sharma, Dheeraj

    2017-01-01

    Establishing a procedure and mechanism for alignment of Ion beams in Neutral Beam (NB) sources for ITER like systems are complex due to large traversal distances (∼21 m) and restricted use of flexible elements into the system. For the beam source of DNB, movement requirements for beam alignment are the combination of tilting (±9mrad), rotation (±9mrad) and translation (±25mm). The present work describes the design development of a system composed of three single ply ‘Gimbal’ type bellow system, placed in series, in L-shaped hydraulic lines (size DN50, DN20 and DN15). The paper shall detail out the generation of initial requirements, transformation of movements at bellow locations, selection of bellows/combination of bellows, minimizing the induced movements by optimization of bellows location, estimation of movements through CEASAR II and the design compliance with respect to EJMA code

  1. Development of neutral beam source using electron beam excited plasma

    International Nuclear Information System (INIS)

    Hara, Yasuhiro; Hamagaki, Manabu; Mise, Takaya; Hara, Tamio

    2011-01-01

    A low-energy neutral beam (NB) source, which consists of an electron-beam-excited plasma (EBEP) source and two carbon electrodes, has been developed for damageless etching of ultra-large-scale integrated (ULSI) devices. It has been confirmed that the Ar ion beam energy was controlled by the acceleration voltage and the beam profile had good uniformity over the diameter of 80 mm. Dry etching of a Si wafer at the floating potential has been carried out by Ar NB. Si sputtering yield by an Ar NB clearly depends on the acceleration voltage. This result shows that the NB has been generated through the charge exchange reaction from the ion beam in the process chamber. (author)

  2. Recent development on RF-driven multicusp H- ion sources

    International Nuclear Information System (INIS)

    Leung, K.N.; De Vries, G.J.; Kunkel, W.B.; Perkins, L.T.; Pickard, D.S.; Saadatmand, K.; Wengrow, A.B.; Williams, M.D.

    1996-06-01

    The radio-frequency (rf) driven multicusp source was originally developed for use in the Superconducting Super Collider injector. The source routinely provided 35 keV, 30 mA of beam at 0.1% duty factor. By using a new cesium dispensing system, beam current in excess of 100 mA and e/H - ∼1 have been observed. For pulse mode operation, the rf discharge can be started by means of a xenon flash lamp. Extracted electrons in the beam can be efficiently removed by employing a permanent magnet insert structure. Chopping of the H - beam can be accomplished by applying a pulsed positive voltage on the plasma electrode

  3. The FEL development at the Advanced Photon Source

    International Nuclear Information System (INIS)

    Arnold, N. D.; Benson, C.; Berg, S.; Berg, W.; Biedron, S. G.; Chae, Y. C.; Crosbie, E. A.; Decker, G.; Dejus, R. J.; Den Hartog, P.; Deriy, B.; Dortwegt, R.; Edrmann, M.; Freund, H. P.; Friedsam, H.; Galayda, J. N.; Gluskin, E.; Goeppner, G. A.; Grelick, A.; Huang, Z.; Jones, J.; Kang, Y.; Kim, K.-J.; Kim, S.; Kinoshita, K.; Lewellen, J. W.; Lill, R.; Lumpkin, A. H.; Makarov, O.; Markovich, G. M.; Milton, S. V.; Moog, E. R.; Nassiri, A.; Ogurtsov, V.; Pasky, S.; Power, J.; Tieman, B.; Trakhtenberg, E.; Travish, G.; Vasserman, I.; Walters, D. R.; Wang, J.; Xu, S.; Yang, B.

    1999-01-01

    Construction of a single-pass free-electron laser (FEL) based on the self-amplified spontaneous emission (SASE) mode of operation is nearing completion at the Advanced Photon Source (APS) with initial experiments imminent. The APS SASE FEL is a proof-of-principle fourth-generation light source. As of January 1999 the undulator hall, end-station building, necessary transfer lines, electron and optical diagnostics, injectors, and initial undulatory have been constructed and, with the exception of the undulatory, installed. All preliminary code development and simulations have also been completed. The undulator hall is now ready to accept first beam for characterization of the output radiation. It is the project goal to push towards fill FEL saturation, initially in the visible, but ultimately to W and VUV, wavelengths

  4. A risk-based evaluation of the impact of key uncertainties on the prediction of severe accident source terms - STU

    International Nuclear Information System (INIS)

    Ang, M.L.; Grindon, E.; Dutton, L.M.C.; Garcia-Sedano, P.; Santamaria, C.S.; Centner, B.; Auglaire, M.; Routamo, T.; Outa, S.; Jokiniemi, J.; Gustavsson, V.; Wennerstrom, H.; Spanier, L.; Gren, M.; Boschiero, M-H; Droulas, J-L; Friederichs, H-G; Sonnenkalb, M.

    2001-01-01

    The purpose of this project is to address the key uncertainties associated with a number of fission product release and transport phenomena in a wider context and to assess their relevance to key severe accident sequences. This project is a wide-based analysis involving eight reactor designs that are representative of the reactors currently operating in the European Union (EU). In total, 20 accident sequences covering a wide range of conditions have been chosen to provide the basis for sensitivity studies. The appraisal is achieved through a systematic risk-based framework developed within this project. Specifically, this is a quantitative interpretation of the sensitivity calculations on the basis of 'significance indicators', applied above defined threshold values. These threshold values represent a good surrogate for 'large release', which is defined in a number of EU countries. In addition, the results are placed in the context of in-containment source term limits, for advanced light water reactor designs, as defined by international guidelines. Overall, despite the phenomenological uncertainties, the predicted source terms (both into the containment, and subsequently, into the environment) do not display a high degree of sensitivity to the individual fission product issues addressed in this project. This is due, mainly, to the substantial capacity for the attenuation of airborne fission products by the designed safety provisions and the natural fission product retention mechanisms within the containment

  5. A simple method for estimating potential source term bypass fractions from confinement structures

    International Nuclear Information System (INIS)

    Kalinich, D.A.; Paddleford, D.F.

    1997-01-01

    Confinement structures house many of the operating processes at the Savannah River Site (SRS). Under normal operating conditions, a confinement structure in conjunction with its associated ventilation systems prevents the release of radiological material to the environment. However, under potential accident conditions, the performance of the ventilation systems and integrity of the structure may be challenged. In order to calculate the radiological consequences associated with a potential accident (e.g. fires, explosion, spills, etc.), it is necessary to determine the fraction of the source term initially generated by the accident that escapes from the confinement structure to the environment. While it would be desirable to estimate the potential bypass fraction using sophisticated control-volume/flow path computer codes (e.g. CONTAIN, MELCOR, etc.) in order to take as much credit as possible for the mitigative effects of the confinement structure, there are many instances where using such codes is not tractable due to limits on the level-of-effort allotted to perform the analysis. Moreover, the current review environment, with its emphasis on deterministic/bounding-versus probabilistic/best-estimate-analysis discourages using analytical techniques that require the consideration of a large number of parameters. Discussed herein is a simplified control-volume/flow path approach for calculating source term bypass fraction that is amenable to solution in a spreadsheet or with a commercial mathematical solver (e.g. MathCad or Mathematica). It considers the effects of wind and fire pressure gradients on the structure, ventilation system operation, and Halon discharges. Simple models are used to characterize the engineered and non-engineered flow paths. By making judicious choices for the limited set of problem parameters, the results from this approach can be defended as bounding and conservative

  6. Source term estimation for small sized HTRs: status and further needs - a german approach

    International Nuclear Information System (INIS)

    Moormann, R.; Schenk, W.; Verfondern, K.

    2000-01-01

    The main results of German studies on source term estimation for small pebble-bed HTRs with their strict safety demands are outlined. Core heat-up events are no longer dominant for modern high quality fuel, but fission product transport during water ingress accidents (steam cycle plants) and depressurization is relevant, mainly due to remobilization of fission products which were plated-out in the course of normal operation or became dust borne. An important lack of knowledge was identified as concerns data on plate-out under normal operation, as well as on the behaviour of dust borne activity as a whole. Improved knowledge in this field is also important for maintenance/repair and design/shielding. For core heat-up events the influence of burn-up on temperature induced fission product release has to be measured for future high burn-up fuel. Also, transport mechanisms out of the He circuit into the environment require further examination. For water/steam ingress events mobilization of plated-out fission products by steam or water has to be considered in detail, along with steam interaction with kernels of particles with defective coatings. For source terms of depressurization, a more detailed knowledge of the flow pattern and shear forces on the various surfaces is necessary. In order to improve the knowledge on plate-out and dust in normal operation and to generate specimens for experimental remobilization studies, planning/design of plate-out/dust examination facilities which could be added to the next generation of HTRs (HTR10,HTTR) is proposed. For severe air ingress and reactivity accidents, behaviour of future advanced fuel elements has to be experimentally tested. (authors)

  7. An artificial neural network approach to reconstruct the source term of a nuclear accident

    International Nuclear Information System (INIS)

    Giles, J.; Palma, C. R.; Weller, P.

    1997-01-01

    This work makes use of one of the main features of artificial neural networks, which is their ability to 'learn' from sets of known input and output data. Indeed, a trained artificial neural network can be used to make predictions on the input data when the output is known, and this feedback process enables one to reconstruct the source term from field observations. With this aim, an artificial neural networks has been trained, using the projections of a segmented plume atmospheric dispersion model at fixed points, simulating a set of gamma detectors located outside the perimeter of a nuclear facility. The resulting set of artificial neural networks was used to determine the release fraction and rate for each of the noble gases, iodines and particulate fission products that could originate from a nuclear accident. Model projections were made using a large data set consisting of effective release height, release fraction of noble gases, iodines and particulate fission products, atmospheric stability, wind speed and wind direction. The model computed nuclide-specific gamma dose rates. The locations of the detectors were chosen taking into account both building shine and wake effects, and varied in distance between 800 and 1200 m from the reactor.The inputs to the artificial neural networks consisted of the measurements from the detector array, atmospheric stability, wind speed and wind direction; the outputs comprised a set of release fractions and heights. Once trained, the artificial neural networks was used to reconstruct the source term from the detector responses for data sets not used in training. The preliminary results are encouraging and show that the noble gases and particulate fission product release fractions are well determined

  8. Radiological consequence evaluation of DBAs with alternative source term method for a Chinese PWR

    International Nuclear Information System (INIS)

    Li, J.X.; Cao, X.W.; Tong, L.L.; Huang, G.F.

    2012-01-01

    Highlights: ► Radiological consequence evaluation of DBAs with alternative source term method for a Chinese 900 MWe PWR has been investigated. ► Six typical DBA sequences are analyzed. ► The doses of control room, EAB and outer boundary of LPZ are acceptable. ► The differences between AST method and TID-14844 method are investigated. - Abstract: Since a large amount of fission products may releases into the environment, during the accident progression in nuclear power plants (NPPs), which is a potential hazard to public risk, the radiological consequence should be evaluated for alleviating the hazard. In most Chinese NPPs the method of TID-14844, in which the whole body and thyroid dose criteria is employed as dose criteria, is currently adopted to evaluate the radiological consequences for design-basis accidents (DBAs), but, due to the total effective dose equivalent is employed as dose criteria in alternative radiological source terms (AST) method, it is necessary to evaluate the radiological consequences for DBAs with AST method and to discuss the difference between two methods. By using an integral safety analysis code, an analytical model of the 900 MWe pressurized water reactor (PWR) is built and the radiological consequences in DBAs at control room (CR), exclusion area boundary (EAB), low population zone (LPZ) are analyzed, which includes LOCA and non-LOCA DBAs, such as fuel handling accident (FHA), rod ejection accident (REA), main steam line break (MSLB), steam generator tube rupture (SGTR), locked rotor accident (LRA) by using the guidance of the RG 1.183. The results show that the doses in CR, EAB and LPZ are acceptable compared with dose criteria in RG 1.183 and the differences between AST method and TID-14844 method are also discussed.

  9. STEPS: source term estimation based on plant status phase 0 - the technical specifications of the containment module

    International Nuclear Information System (INIS)

    Vamanu, D.V.

    1998-01-01

    In the framework of Project RODOS (Real-Time On-Line Decision Support System for Nuclear Emergencies in Europe), the European Atomic Energy Community (EAEC) of the Commission of the European Communities has commissioned the development of a unified concept, body of knowledge, models and software package meant to assist the evaluation of the source term of severe nuclear accidents in light water reactors of the types prevailing on the Continent. Code-named STEPS, for 'Source Term Estimation based on Plant Status', the project has evolved as Contract RODOS D (FI4P-CT96-0048), between EAEC and consortium of expert European centres including Commissariat a l'Energie Atomique, Institut de Protection et de Surete Nucleaire, (CEA-DPI-SEAC) as Coordinator and Forschungszentrum Karlsruhe GmbH (FZK-INR), the Finnish Centre for Radiation and Nuclear Safety, (STUK-NSD), the Technical Research Centre of Finland, Energy, Nuclear Energy (VTT-ET-NE), and Eidgenossische Technische Hochschule - ETH Zurich, Centre of Excellence (ETH-CERS) as Contractors. For the Phase 0 of the project, an IFIN-HH expert has been assigned by ETH-CERS to develop the Technical Specifications of the delivery component of the intended STEPS package, the CONTAINMENT Module. Sponsored by ETH-CERS headquarters in Zurich, the work was done on the premises and with the logistic support of CEA D PI-SEAC at Fontenay-aux-Roses, with the feedback processing and computer code development subsequently performed in Bucharest. The Technical Specifications of the STEPS CONTAINMENT Module were guided by specific terms of reference, including: (i) the capability of the software to function as a source term interface between targeted nuclear power plants and the RODOS System; (ii) the comparable capability of the system to be operated as a stand-alone assessment and decision support tool for a comprehensive variety of plants, nuclear emergency classes. On the technical side, the specifications had to focus on the possible

  10. Real-time software for multi-isotopic source term estimation

    International Nuclear Information System (INIS)

    Goloubenkov, A.; Borodin, R.; Sohier, A.

    1996-01-01

    Consideration is given to development of software for one of crucial components of the RODOS - assessment of the source rate (SR) from indirect measurements. Four components of the software are described in the paper. First component is a GRID system, which allow to prepare stochastic meteorological and radioactivity fields using measured data. Second part is a model of atmospheric transport which can be adapted for emulation of practically any gamma dose/spectrum detectors. The third one is a method which allows space-time and quantitative discrepancies in measured and modelled data to be taken into account simultaneously. It bases on the preference scheme selected by an expert. Last component is a special optimization method for calculation of multi-isotopic SR and its uncertainties. Results of a validation of the software using tracer experiments data and Chernobyl source estimation for main dose-forming isotopes are enclosed in the paper

  11. Size distribution, directional source contributions and pollution status of PM from Chengdu, China during a long-term sampling campaign.

    Science.gov (United States)

    Shi, Guo-Liang; Tian, Ying-Ze; Ma, Tong; Song, Dan-Lin; Zhou, Lai-Dong; Han, Bo; Feng, Yin-Chang; Russell, Armistead G

    2017-06-01

    Long-term and synchronous monitoring of PM 10 and PM 2.5 was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by two-way and three-way receptor models (PMF2, ME2-2way and ME2-3way). Consistent results were found: the primary source categories contributed 63.4% (PMF2), 64.8% (ME2-2way) and 66.8% (ME2-3way) to PM 10 , and contributed 60.9% (PMF2), 65.5% (ME2-2way) and 61.0% (ME2-3way) to PM 2.5 . Secondary sources contributed 31.8% (PMF2), 32.9% (ME2-2way) and 31.7% (ME2-3way) to PM 10 , and 35.0% (PMF2), 33.8% (ME2-2way) and 36.0% (ME2-3way) to PM 2.5 . The size distribution of source categories was estimated better by the ME2-3way method. The three-way model can simultaneously consider chemical species, temporal variability and PM sizes, while a two-way model independently computes datasets of different sizes. A method called source directional apportionment (SDA) was employed to quantify the contributions from various directions for each source category. Crustal dust from east-north-east (ENE) contributed the highest to both PM 10 (12.7%) and PM 2.5 (9.7%) in Chengdu, followed by the crustal dust from south-east (SE) for PM 10 (9.8%) and secondary nitrate & secondary organic carbon from ENE for PM 2.5 (9.6%). Source contributions from different directions are associated with meteorological conditions, source locations and emission patterns during the sampling period. These findings and methods provide useful tools to better understand PM pollution status and to develop effective pollution control strategies. Copyright © 2016. Published by Elsevier B.V.

  12. Source term and activation calculations for the new TR-FLEX cyclotron for medical applications at HZDR

    Energy Technology Data Exchange (ETDEWEB)

    Konheiser, Joerg [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Reactor Safety; Ferrari, A. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Radiation Physics; Magin, A. [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany); Naumann, B. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Dept. of Radiation Protection and Safety; Mueller, S.E.

    2017-06-01

    The neutron source terms for a proton beam hitting an {sup 18}O-enriched water target were calculated with the radiation transport programs MCNP6 and FLUKA and were compared to source terms for exclusive {sup 18}O(p,n){sup 18}F production. To validate the radiation fields obtained in the simulations, an experimental program has been started using activation samples originally used in reactor dosimetry.

  13. A simplistic view of the iodine chemistry influence on source term assessment

    International Nuclear Information System (INIS)

    Herranz, L.E.; Rodriguez, J.J.

    1994-01-01

    The intrinsic characteristics of iodine make it a relevant concern as to its potential radiobiological impact in case of a hypothetical severe accident in nuclear power plants. This paper summarizes the major results drawn from a very simple but illustrative calculation exercise aimed at weighing how significant could be taking iodine chemistry in containment into account for source term assessments in case of a postulated severe reactor accident. The scenario chosen as representative of expected conditions in containment was LA-4 test of LACE programme. Several approximations and hypothesis concerning the scenario were necessary. Iodine chemistry analyses were performed with IODE code, as long as thermalhydraulic and aerosol behaviour analyses, providing initial and boundary conditions for iodine calculations, were carried out with CONTEMPT4/MOD5 and NAUA/MOD5 codes, respectively. In general, the results obtained agreed qualitatively with the current knowledge on the area; from a quantitative point of view, one of the major results was that iodine chemistry on acidic conditions could provide a substantial increase in the leaked mass from containment under the postulated circumstances. Hence, this study underlines the need of including iodine chemistry in source tenn assessments. (author)

  14. Uncertainties in source term calculations generated by the ORIGEN2 computer code for Hanford Production Reactors

    International Nuclear Information System (INIS)

    Heeb, C.M.

    1991-03-01

    The ORIGEN2 computer code is the primary calculational tool for computing isotopic source terms for the Hanford Environmental Dose Reconstruction (HEDR) Project. The ORIGEN2 code computes the amounts of radionuclides that are created or remain in spent nuclear fuel after neutron irradiation and radioactive decay have occurred as a result of nuclear reactor operation. ORIGEN2 was chosen as the primary code for these calculations because it is widely used and accepted by the nuclear industry, both in the United States and the rest of the world. Its comprehensive library of over 1,600 nuclides includes any possible isotope of interest to the HEDR Project. It is important to evaluate the uncertainties expected from use of ORIGEN2 in the HEDR Project because these uncertainties may have a pivotal impact on the final accuracy and credibility of the results of the project. There are three primary sources of uncertainty in an ORIGEN2 calculation: basic nuclear data uncertainty in neutron cross sections, radioactive decay constants, energy per fission, and fission product yields; calculational uncertainty due to input data; and code uncertainties (i.e., numerical approximations, and neutron spectrum-averaged cross-section values from the code library). 15 refs., 5 figs., 5 tabs

  15. Long-term monitoring on environmental disasters using multi-source remote sensing technique

    Science.gov (United States)

    Kuo, Y. C.; Chen, C. F.

    2017-12-01

    Environmental disasters are extreme events within the earth's system that cause deaths and injuries to humans, as well as causing damages and losses of valuable assets, such as buildings, communication systems, farmlands, forest and etc. In disaster management, a large amount of multi-temporal spatial data is required. Multi-source remote sensing data with different spatial, spectral and temporal resolutions is widely applied on environmental disaster monitoring. With multi-source and multi-temporal high resolution images, we conduct rapid, systematic and seriate observations regarding to economic damages and environmental disasters on earth. It is based on three monitoring platforms: remote sensing, UAS (Unmanned Aircraft Systems) and ground investigation. The advantages of using UAS technology include great mobility and availability in real-time rapid and more flexible weather conditions. The system can produce long-term spatial distribution information from environmental disasters, obtaining high-resolution remote sensing data and field verification data in key monitoring areas. It also supports the prevention and control on ocean pollutions, illegally disposed wastes and pine pests in different scales. Meanwhile, digital photogrammetry can be applied on the camera inside and outside the position parameters to produce Digital Surface Model (DSM) data. The latest terrain environment information is simulated by using DSM data, and can be used as references in disaster recovery in the future.

  16. Integral migration and source term experiments on cement and bitumen waste forms

    International Nuclear Information System (INIS)

    Ewart, F.T.; Howse, R.M.; Sharpe, B.M.; Smith, A.J.; Thomason, H.P.; Williams, S.J.; Young, M.

    1986-01-01

    This is the final report of a programme of research which formed a part of the CEC joint research project into radionuclide migration in the geosphere (MIRAGE). This study addressed the aspects of integral migration and source term. The integral migration experiment simulated, in the laboratory, the intrusion of water into the repository, the leaching of radionuclides from two intermediate level wasteforms and the subsequent migration through the geosphere. The simulation consisted of a source of natural ground water which flowed over a sample of wasteform, at a controlled redox potential, and then through backfill and geological material packed in columns. The two wasteforms used here were cemented waste from the WAK plant at Karlsruhe, W. Germany and bitumenised intermediate concentrates from the Marcoule plant in France. The soluble fission products such as caesium wire rapidly released from the cemented waste but the actinides, and technetium in the reduced state, were retained in the wasteform. The release of all nuclides from the bitumenised waste was very low. (author)

  17. Integral migration and source-term experiments on cement and bitumen waste forms

    International Nuclear Information System (INIS)

    Ewart, F.T.; Howse, R.M.; Sharpe, B.M.; Smith, A.J.; Thomason, H.P.; Williams, S.J.; Young, M.

    1986-01-01

    This is the final report of a programme of research which formed a part of the CEC joint research project into radionuclide migration in the geosphere (MIRAGE). This study addressed the aspects of integral migration and source term. The integral migration experiment simulated, in the laboratory, the intrusion of water into the repository, the leaching of radionuclides from two intermediate-level waste-forms and the subsequent migration through the geosphere. The simulation consisted of a source of natural ground water which flowed over a sample of waste-form, at a controlled redox potential, and then through backfill and geological material packed in columns. The two waste forms used here were cemented waste from the WAK plant at Karlsruhe in the Federal Republic of Germany and bitumenized intermediate concentrates from the Marcoule plant in France. The soluble fission products such as caesium were rapidly released from the cemented waste but the actinides, and technetium in the reduced state, were retained in the waste-form. The released of all nuclides from the bitumenized waste was very low

  18. Developing hydrogen infrastructure through near-term intermediate technology

    International Nuclear Information System (INIS)

    Arthur, D.M.; Checkel, M.D.; Koch, C.R.

    2003-01-01

    The development of a vehicular hydrogen fuelling infrastructure is a necessary first step towards the widespread use of hydrogen-powered vehicles. This paper proposes the case for using a near-term, intermediate technology to stimulate and support the development of that infrastructure. 'Dynamic Hydrogen Multifuel' (DHM) is an engine control and fuel system technology that uses flexible blending of hydrogen and another fuel to optimize emissions and overall fuel economy in a spark ignition engine. DHM vehicles can enhance emissions and fuel economy using techniques such as cold-starting or idling on pure hydrogen. Blending hydrogen can extend lean operation and exhaust gas recirculation limits while normal engine power and vehicle range can be maintained by the conventional fuel. Essentially DHM vehicles are a near-term intermediate technology which provides significant emissions benefits in a vehicle which is sufficiently economical, practical and familiar to achieve significant production numbers and significant fuel station load. The factors leading to successful implementation of current hydrogen filling stations must also be understood if the infrastructure is to be developed further. The paper discusses important lessons on the development of alternative fuel infrastructure that have been learned from natural gas; why were natural gas vehicle conversions largely successful in Argentina while failing in Canada and New Zealand? What ideas can be distilled from the previous successes and failures of the attempted introduction of a new vehicle fuel? It is proposed that hydrogen infrastructure can be developed by introducing a catalytic, near-term technology to provide fuel station demand and operating experience. However, it is imperative to understand the lessons of historic failures and present successes. (author)

  19. High-level Waste Long-term management technology development

    International Nuclear Information System (INIS)

    Choi, Jong Won; Kang, C. H.; Ko, Y. K.

    2012-02-01

    The purpose of this project is to develop a long-term management system(A-KRS) which deals with spent fuels from domestic nuclear power stations, HLW from advanced fuel cycle and other wastes that are not admitted to LILW disposal site. Also, this project demonstrate the feasibility and reliability of the key technologies applied in the A-KRS by evaluating them under in-situ condition such as underground research laboratory and provide important information to establish the safety assessment and long-term management plan. To develop the technologies for the high level radioactive wastes disposal, demonstrate their reliability under in-situ condition and establish safety assessment of disposal system, The major objects of this project are the following: Ο An advanced disposal system including waste containers for HLW from advanced fuel cycle and pyroprocess has been developed. Ο Quantitative assessment tools for long-term safety and performance assessment of a radwaste disposal system has been developed. Ο Hydrological and geochemical investigation and interpretation methods has been developed to evaluate deep geological environments. Ο The THMC characteristics of the engineered barrier system and near-field has been evaluated by in-situ experiments. Ο The migration and retardation of radionuclides and colloid materials in a deep geological environment has been investigated. The results from this project will provide important information to show HLW disposal plan safe and reliable. The knowledge from this project can also contribute to environmental conservation by applying them to the field of oil and gas industries to store their wastes safe

  20. International sources of financial cooperation for health in developing countries.

    Science.gov (United States)

    Howard, L M

    1983-01-01

    By direct consulation and review of published sources, a study of 16 selected official sources of international financial cooperation was conducted over the August 1979 to August 1980 period in order to assess the policies, programs, and prospects for support of established international health goals. This study demonstrated that approximately 90% of the external health sector funds are provided via development oriented agencies. The major agencies providing such assistance concur that no sector, including health, should be excluded "a priori," providing that the requesting nation conveys its proposals through the appropriate national development planning authority. The agencies in the study also were found to be supporting health related programs in all the geographic regions of the World Health Organization (WHO). An associated review of 30 external funding agencies revealed that only 5 reported providing health assistance in more than half of the countries where they provided assistance for general development purposes. Interviewed sources attributed this to the limited manner in which health proposals have been identified, prepared, and forwarded (with national development authority approval) to international agencies. In 1979 concessional development financing totaled approximately US$29.9 billion, US$24.2 billion being provided by 17 major industrial nations, US$4.7 billion by Organization of Petroleum Exporting (OPEC) countries, and less than US$1 billion by the countries of Eastern Europe. Approximately 2/3 of such concessional financing is administered bilaterally, only 1/3 passing through multilateral institutions. UN agencies receive only 12% of these total concessional development financing resources. In 1979, concessional funding for health totaled approximately US$3 billion, approximately 1/10 of which was administered by WHO and its regional offices. It is anticipated that future international funding for health in developing countries will continue