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The U.S. Nuclear Regulatory Commission has developed regulations regarding the siting and design of nuclear power plants (NPPs) that are aimed at addressing various natural hazards, including flooding. Flood barriers are designed to prevent water from entering NPP areas containing structures, systems, and components (SSCs) important to safety. The barriers are used at NPPs along with drains, sumps, pumps, valves, plugs, and site grading as part of the plant flood protection features that protect SSCs from experiencing external or internal flooding and mitigate the effects of flooding on NPP operations. The performance of flood protection features, including flood barriers at NPPs, has been an ongoing concern. Domestic and international operational experience provides clear indications that flood barrier performance has significant safety implications, especially for aging NPPs. The observed deficiencies show that flood barriers should be designed and installed properly, then adequately tested, inspected, and maintained in order to ensure that they perform their intended functions during flooding events. This paper reviews available information related to flood barriers employed at U.S. NPPs and provides an overview and categorization of NPP flood barriers. It identifies potential domestic and international flood barrier testing facilities, including operating and decommissioned U.S. NPPs. Finally, this paper presents the technical and logistical considerations that should be made when developing specific testing strategies and protocols for flood barriers, such as the selection of flood barriers, test locations, testing approach, performance criteria, and testing parameters. [ABSTRACT FROM AUTHOR]

The foundation of the Versatile Economic Risk Tool is based on the methodologies of the Generation Risk Assessment (GRA) and uses a systematic approach to prioritizing systems, structures, and components based on estimated operation reliability and the impact on future power generation. The GRA provides management with insight that helps with decisions on maintenance, component repair/replacement, design modifications, and other issues associated with electricity generation and equipment reliability programs. Although the benefit of the GRA is understood in the nuclear community, there are negative aspects associated with the current approaches. Traditional GRA modeling is time consuming, convoluted, and considers only the static portion of generation risks. The Versatile Economic Risk Tool addresses the drawbacks of the traditional GRA through simplifying and/or automating the requirements for an effective GRA model. The Versatile Economic Risk Tool also integrates in-depth parametric variability within models to evaluate system, structure, and component generation risks as a function of time. The Versatile Economic Risk Tool addresses the shortcomings of the GRA by automating the study of equipment reliability and degradation from an electricity generation perspective by coupling fault tree analysis and statistical analysis software that support repetitive, parametric analyses. Versatile Economic Risk Tool case studies are presented to provide insight into the potential benefit provided. [ABSTRACT FROM AUTHOR]

This paper discusses a new method of simulating the fuel assembly duct-bowing reactivity coefficient for EBR-II run 138B. Quantification of the fuel assembly duct-bowing reactivity effect in liquid metal–cooled fast reactors has been a persistent problem since they were first designed and operated. Simulation of the duct-bowing reactivity effect is difficult because the level of detail required to simulate the effect has exceeded most modeling capabilities. The new method outlined in this paper utilizes the finite element analysis code ANSYS to analyze the thermal and structural components. The displacement of the fuel assembly duct due to thermal expansion and mechanical interaction was calculated by ANSYS using recorded EBR-II run 138B temperature and power boundary value data. The displacement values were incorporated into to a Monte Carlo model of EBR-II run 138B and keff was calculated. Multiple Monte Carlo calculations were performed with duct displacement values corresponding to different reactor temperatures. Using the calculated keff values associated with the different duct displacement results allowed calculation of the duct-bowing reactivity coefficient. The duct-bowing reactivity coefficient was calculated to be −14.5 × 10−4 $/°C/ ± 4.4%. [ABSTRACT FROM AUTHOR]

Flooding is a hazard for nuclear power plants (NPPs) and has caused extensive damage and economic impact. Improved NPP flooding risk characterization starts with improving scenario realism by using physics-based flooding simulations. Smoothed particle hydrodynamics (SPH) is one method for modeling fluid flow and is being investigated for NPP flooding simulation. While still in its infancy as a fluid simulation tool, SPH offers enticing features especially in three-dimensional modeling. However, when conducting SPH simulations, users must establish, inter alia, the appropriate particle spacing, which can be a tedious and time-consuming process. This paper describes the coupling of the SPH code Neutrino and the Idaho National Laboratory developed Risk Analysis Virtual Environment (RAVEN). By coupling Neutrino and RAVEN, the RAVEN optimization capabilities can now be applied to the particle spacing selection problem. A brief description of SPH, the overall capabilities of RAVEN, and the protocol used to couple the codes are provided. Additionally, the paper details a hypothetical problem and demonstrates the ability of automating the particle spacing selection and performing an example particle spacing optimization using RAVEN. With the Neutrino/RAVEN coupling established, a wide range of capabilities can now be utilized including optimization, reduced order model training and analysis, uncertainty quantification, sensitivity analysis, etc. Previously, these capabilities would require extensive work and time from the Neutrino user. Now, these capabilities are readily available and require only the creation of a RAVEN input file. [ABSTRACT FROM AUTHOR]

This paper offers a typology of hillfort gate-mechanisms, and a developed understanding of temporal depth in hillfort architecture – via applied contextual analysis. Rediscovery of the Eddisbury hillfort archive revealed three iron gate-mechanisms. To situate these rare objects, detailed analyses of entrance architecture and stratigraphy was conducted – for Eddisbury and parallels (Hembury, South Cadbury) – enabling new sequences, resolution of the Mid-Late Cadbury sequence, and reconstruction of the Cadbury gate-fittings. Crucially, Bayesian analysis of C-14 dates from Eddisbury confirm a 400 BC date for developed hillforts. Eddisbury's gate-mechanisms are revealed as the earliest in Europe, with Roman adoption of Iron Age technology. [ABSTRACT FROM AUTHOR]

The Transient Reactor Test (TREAT) facility was designed and built in the late 1950s. The air-cooled reactor design incorporates fuel composed of highly enriched uranium dispersed in graphite with a 10 000:1 carbon-to-uranium atom ratio to provide a very fast-acting highly negative temperature coefficient of reactivity. The reactor utilizes a forced-air-cooling system for decay heat removal, with a primary function of reducing the time at temperature (oxidation) of the reactor fuel cladding. The simple design with lack of a cooling system pressure boundary provides relatively easy access for instrumentation and experiments. The large thermal mass of the reactor and the simple design allow for high-power transients approaching 18 000 MW in an inherently safe manner. The simple design has allowed TREAT to operate successfully for 35 years before being placed in standby in 1994 and subsequently restarted in 2017 after more than 20 years of standby to continue the transient fuel testing mission in the United States. This technical note addresses the reactor design and experiment capabilities. [ABSTRACT FROM AUTHOR]

Argonne National Laboratory and Merrick & Company developed the conceptual design of a pilot-scale (100 T/year) pyroprocessing facility for the treatment of used fuel generated by commercial light water reactors and subsequent treatment of waste streams generated during the process. The primary purpose of this study was to perform sufficient engineering for the pilot facility conceptual design so that credible capital and operating cost estimates could be developed. Initial safety, safeguards, and security assessments were also completed to provide a detailed evaluation in these areas that can significantly affect both capital and operating costs. Electrorefining-based pyroprocessing resulted in a compact hot-cell facility with few process equipment systems. The process equipment and support systems were estimated to cost $93 million and the facility $305 million for a project total cost of $398 million. The annual operating cost was estimated at $53 million/year. Scaling up to a commercial-scale (400 T/year) was also evaluated and the capital cost was estimated at $911 million with annual operating cost of $90 million/year. [ABSTRACT FROM AUTHOR]

A conceptual low-enrichment uranium (LEU) fuel design has been developed for the Advanced Test Reactor (ATR) at Idaho National Laboratory. The ATR is currently fueled with a high-enrichment fuel but is slated to be converted to LEU under programs led by the National Nuclear Security Administration of the U.S. Department of Energy. A conceptual LEU fuel design, the Enhanced LEU Fuel (ELF), has been developed assuming power peaking control through the use of variable fuel meat thicknesses and no use of burnable poison. In initial work, this design was shown to satisfy performance requirements for ATR operation. Following these design calculations, a safety analysis process was initiated to demonstrate that the ELF design would successfully meet safety limits for postulated accident conditions. Those calculations, performed using RELAP5 and ATR-SINDA, require physics analysis to provide spatial power distributions and kinetics parameters for various core operations configurations. This article describes the findings of the physics analysis and provides predictions for the behavior of a LEU-fueled version of ATR, and compares these to calculations of the performance of the current high-enrichment uranium fuel. [ABSTRACT FROM PUBLISHER]

Background: Myofascial pain that has been associated with cancer and increased risk of morbidity and mortality in cancer patients is intrinsically associated with low magnesium and low 25-hydroxyvitamin D (25(OH)D). Therefore, this physical finding was used as a clinical diagnostic proxy.Objective: The objective of this study was to assess the association and prevalence of disease in individuals with myofascial pain and low 25(OH)D in a county with low magnesium in the drinking water.Design: This is a retrospective cross-sectional study of a chart review of 269 subjects to assess subjects presenting with myofascial pain (assessed by tender trigger points) and 25(OH)D concentrations below 30 ng/mL or a history of 25(OH)D deficiency compared to those without these exposures.Results: The association between the exposure of low 25(OH)D levels and myofascial pain was compared to all cancers, colon polyps, and tendon ruptures. The odds of having cancer with the combined exposures was 10.14 times the odds of not having either exposure (95% confidence interval [CI], 5.08, 20.25, p < 0.001). For adenomatous colon polyps, the odds ratio (OR) was 7.24 (95% CI, 3.83, 13.69, p < 0.001), and for tendon rupture, the OR was 8.65 (95% CI, 3.76, 19.94, p < 0.001). Of 80 subjects who had both myofascial pain and 25(OH)D less than 30 ng/mL, 74 were tested for red blood cell (RBC) magnesium. Half of those subjects had RBC magnesium concentrations < 4.6 mg/dL, and 23% had levels below the reference range (4.0-6.4 mg/dL).Conclusion: Myofascial pain as assessed by tender trigger points and 25(OH)D deficiency showed a significant association with cancer, adenomatous colon polyps, and tendon rupture. Further studies to verify these results are needed, especially in areas where there is low magnesium in the drinking water. [ABSTRACT FROM AUTHOR]

The purpose of this research was to identify game patterns in rugby sevens, and utilise a Markov chain, to detect how scoring plays are likely to develop. Using notational analysis, a total of 5413 phases were coded from 117 Men’s World Rugby Sevens Series games. Results of a Fisher’s exact test identified significant differences between game patterns in pool games and finals games (p < 0.01) and category 1 games (top 4 ranked vs top 4 ranked teams) and category 2 games (all other games) (p < 0.01). Markov chain analysis revealed that some scoring phases were a result of the previous phase actions. These findings met the Markov assumption that the probability of transition to the next state depends only on the current state. Scoring phases that met the Markov assumption tended to relate to transitional plays resulting from turnovers in possession. The findings suggest that rugby sevens teams should incorporate unstructured practise that involving transitioning from defence to attack, attack to defence and structured defence to unstructured defence into their training. [ABSTRACT FROM PUBLISHER]

This article examines a key aspect of American sports history within a transnational context. Whilst the internal histories of American sport are exceedingly rich and voluminous, our general understanding of the nation’s contribution to the international, global scene is less well-known. The postcolonial rivalries between American and British sports communities fuelled the development of what became open, international cup competitions in such sports as tennis and golf which bolstered an emerging global industry in the first half of the twentieth century. The transnational process of initial American imitation and absorption of British models have been well documented within the scholarly literature and debates in American Studies for decades; however, the gradual reversal of this imitative process to a more reciprocal relationship has received far less attention (especially within sports history). The authors show how the Davis Cup competition is an example of the way in which Americans indigenised a cultural sporting import, namely tennis; created a nationalistic, international sporting competition; and effectively exported it back to Britain within the wider context of a burgeoning, imperial rivalry on the world stage between these two, rival sporting nations. This process not only expanded the worldwide consumption of sport but spreads a spirit of cultural emulation within twentieth-century global consumer culture. This transnational perspective also illuminates the thorough de-provincialising of the notion of “American Exceptionalism” within the field. When, for example, the respective imperial histories of the two nations are considered comparatively, the “American” story does not look so “exceptional” after all. Though American exceptionalism adapted some British sports to suit American sensibilities, the sporting cultures of the two nations and within their zones of influence remained similar in many respects. This was particularly true in amateur sports such as tennis, rowing and track and field (athletics to the Brits) as well as in the sport of golf. In the twentieth century, many sports adapted as focus shifted from nationalism and national worth towards professionalism and international spectacle. [ABSTRACT FROM PUBLISHER]

The article discusses a research conducted to examine the dietary effects of combination of pigmented rice bran and plant sterol on lipid profiles in overweight and obese adults. Topics discussed include randomized study of 24 overweight and obese adults, use of accelerometry and anthropometrics. It concludes that nutrient-balanced diet supplemented with plant sterols and rice bran resulted in decrease in total and low density lipoprotein (LDL) cholesterol in overweight and obese adults.

Argonne National Laboratory (Argonne), with the support of the US Department of Energy (DOE) Packaging Certification Program, has developed a week long training course on security for nuclear and other radioactive materials during transport. The course focuses on USA domestic and international requirements and recommendations for transport security. A review of applicable US Department of Transportation regulations, recently issued US Nuclear Regulatory Commission regulations, DOE orders and manuals, and relevant international modal regulatory documents relating to transport security was conducted. The review disclosed that existing International Atomic Energy Agency security training materials could be incorporated into a training course on security requirements for US domestic shippers. Development of training materials for such a course was initiated in late 2012, and the first course was convened in early December 2013 at Argonne. The course also incorporated training and hands on transport security applications of the ARG-US Radio Frequency Identification (RFID) system for monitoring the state of health of packages of radioactive and other hazardous materials and for tracking the location of the packages and conveyances during transport and in transit storage. Participants of this initial course obtained insight into both US and international security measures needed for transport and for in transit stopping and storage; gained experience in preparing transport security plans (TSPs) for specific shipments, in performing readiness reviews based on those TSPs, and in identifying needed corrective actions and taking steps to correct deficiencies; and learned by hands on exercises how to apply the ARG-US RFID system to enhance transport security. [ABSTRACT FROM AUTHOR]

The essence of the graded approach is the establishment of applicable quality assurance (QA) requirements to an extent consistent with the importance to safety of an item, component, system or activity. The genesis of the graded approach is a study conducted by the US Nuclear Regulatory Commission (NRC) for the US Congress in 1987 to assess the effectiveness of QA activities. That study demonstrated the need to improve the application of QA requirements for the nuclear industry in general. The conclusion of the study indicated that a graded approach for establishing QA requirements is the most viable method to satisfy federal safety standards that result in protecting public health and safety. The application of QA requirements for type B and fissile material transportation packagings is not based solely on importance to safety or safety related considerations. The operability of items, components, systems and activities is considered to be equally important. The nuclear industry, along with regulatory agencies, recognises the significance of operability considerations, as well as the evaluation of each item, component, system or activity for safety related considerations. The graded approach for QA requirements for type B and fissile material transportation packagings is based on Title 10, Part 71 of the US Code of Federal Regulations (CFR), 'Packaging and transportation of radioactive material.' Guidance for implementation of the QA requirements specified in §71 is provided in NRC Regulatory Guide 7·10, 'Establishing quality assurance programmes for packaging used in transport of radioactive material,' and ASME NQA-1, 'Quality assurance requirements for nuclear facility applications'. The graded approach for QA requirements is based on criteria for containment, shielding and subcriticality specified in 10 CFR Part 71. [ABSTRACT FROM AUTHOR]

In a companion PATRAM 2013 paper, C. Bajwa et al. provide an overview of international level efforts that began in 2010 to develop a comprehensive and detailed Technical Basis Document (TecBasDoc) to support the current International Atomic Energy Agency (IAEA) Transport Regulations (SSR-6, 2012) and future revisions thereto. The draft TecBasDoc that has so far resulted from efforts by a large number of IAEA staff and international experts exceeds 300 pages in length using, to the greatest extent possible, historical documents dating as far back as the 1950s as reference material. The intent is to capture, for those Member States new to transport and for future generations, the scientific and technical heritage of the several decades of development that has occurred in transport safety, preserving this knowledge for future reference. The latest effort, in December 2012, involved consultants to the IAEA adapting the draft to reflect guidance from the IAEA's Transport Safety Standards Committee and delving into the IAEA's archives searching out many long sought, older supporting documents. This paper elaborates on Chaps. 8-10 of the TecBasDoc, dealing with respectively Classification of Materials, Classification of Packages and Package Design and Testing. Chapter 8 elaborates on the many decisions resulting in an initial nine material classifications, which focused more on the physical and not the radioactive characteristics of the materials, to the current, significantly different classifications that focus more on the material's radioactive properties. Chapters 9 and 10 combine to provide extensive, detailed elaboration on why decisions were made concerning the various package classifications and the associated design, testing and acceptance requirements associated with each package type. Chapter 10 cites two extensive supporting appendices. These three chapters and two appendices currently cite and elaborate on >200 historical documents. Efforts are underway to make this extensive document base more complete and to make as many documents as possible available electronically. In this paper, each of these three drafted chapters and the two supportive appendices are overviewed, providing insight into key and typical findings that have been uncovered and incorporated into the draft document. The many experts who have contributed to the current draft are appropriately acknowledged. [ABSTRACT FROM AUTHOR]

The International Atomic Energy Agency (IAEA) is responsible for developing safety requirements for the transport of radioactive material. These requirements were first published in 1961 as 'Regulations for the Safe Transport of Radioactive Material', Safety Series No. 6 (the Regulations), and have been revised at regular intervals, in consultation with Member States, and with input from other relevant organisations, as appropriate. The current regular review and revision of the Regulations has been driven by problems, challenges and the demand for improvements, as well as the need to take into account experiences in transport, newly identified issues, new technologies, best practices, the demand for sustainable transport and harmonisation. After 50 years, 15 editions of the Regulations have been published. With the passage of time, the scientific and technical heritage of several decades of development in transport safety has begun to fade. The need to capture valuable knowledge, which needs to be preserved for future reference, has become clear. In general, every requirement in the regulations was developed on the basis of deliberations among international experts and an appropriate technical basis. The knowledge bases for these often exist in a decentralised manner in many Member States with mature nuclear programmes. Easier access to the existing technical bases for the Regulations could lead to a more comprehensive understanding of the Regulations. Knowledge capture and transfer can contribute to the development of and innovations in transport safety. This paper provides an overview of international level efforts that began in 2010 to develop a comprehensive and detailed technical basis document (TecBasDoc) to support the current and future revisions of the Regulations. The draft TecBasDoc has so far resulted from efforts by IAEA staff and a large number of international transport experts. It exceeds 150 pages in length using, to the greatest extent possible, historical documents dating as far back as the 1950s as reference material. The intent of this effort is to record, for those Member States new to transport and for future generations, the scientific and technical heritage of several decades of development that has occurred in transport safety and to capture valuable knowledge so it can be preserved for future reference. The latest effort has involved consultants to the IAEA adapting the draft to reflect guidance from the IAEA's Transport Safety Standards Committee (TRANSSC) and delving into the IAEA's archives and other sources of historical documents, searching out many long sought, older supporting documents. The draft is currently structured into 12 chapters, embodying multiple supporting appendixes. This paper elaborates on the first chapters of the document, which include General History, Fundamental Safety Principles, Safety Objectives and Principles for Transport, General Safety Requirements, Radiation Protection and Controls for Transport. Two companion papers at PATRAM 2013 address the status of the TecBasDoc in the topical areas of package testing and criticality control. In all cases, the chapters of the TecBasDoc address how early decisions were made citing well known historical experts and discussing how these initial decisions have been adapted to meet the emerging international safety guidelines. [ABSTRACT FROM AUTHOR]

This paper compares measured results with simulation results of neutron beam transmission through an irradiated fuel assembly. The main objective of the comparison is to establish the technical foundation for using Monte Carlo simulation to evaluate the feasibility of using neutron computed tomography for irradiated fuel assembly inspection. The measured results were obtained from an irradiated fuel assembly from the Experimental Breeder Reactor II (EBR-II), and the neutron beam was produced by the Argonne National Laboratory Neutron Radiography Reactor (NRAD). The measurements consist of a projection profile representing the relative neutron beam attenuation at a specific fuel assembly axial elevation obtained from digitized neutron radiography film. Simulation of the neutron beam and fuel assembly was performed using the Monte Carlo code MCNP5. Results presented include the measured beam. attenuation protection profile, simulated neutron beam attenuation protection profiles, parametric study of simulation results, and comparison of the projection results. Comparison of the radiography-based measurement with the simulation results shows good agreement, thereby confirming that Monte Carlo simulation of neutron transmission through an irradiated fuel assembly using MCNP5 is a reliable method for evaluating the use of neutron computed tomography as a means of inspecting irradiated fuel assemblies. [ABSTRACT FROM AUTHOR]

The article presents a comprehensive history of the Packaging, Transport, Storage & Security of Radioactive Material (PATRAM) awards from year 2007 to 2013 of the PATRAM International symposia. It cites the awardees of the PATRAM 2013 which includes Jim Shuler, Franz Hilbert and Koji Shirai. It also mentions that Martine Young, widow of Clive Young started the sponsorship of two awards for young scientists and engineers.

Introduction Intensive care unit (ICU) care provided to children with complex chronic medical and neurological conditions is a frequent source of conflict and distress. Objective To quantify the extent to which pediatric ICU (PICU) nurses (RNs) and respiratory therapists (RTs) experience distress when caring for children with complex medical and developmental disabilities, and to explore which provider characteristics lessen or increase this distress. Methods RNs and RTs at three pediatric hospitals completed an online scenario-based survey to assess their feelings toward a hypothetical patient with complex, chronic medical conditions, and neurological impairment. Twenty-four statements were created to capture features of moral distress, mismatch of expectations, and job dissatisfaction, and providers indicated degree of agreement with each statement. Responses were tabulated to create a Total Distress Score (TD) which was further subdivided into Moral Distress (MD), Mismatch of Expectations (ME), and Job Dissatisfaction (JD) sub-scores. Results One hundred and fifty-five providers completed the survey. RNs and RTs expressed a wide variability of distress in relation to care provided to this hypothetical patient. No single demographic factor consistently accounted for the variability in distress levels. Providers who would have personally opted against aggressive treatment had a statistically significant increase in the level of distress. ME was strongly correlated with both MD and JD scores. Conclusions Providing bedside care to children with complex chronic medical and neurological conditions is associated with wide variability in the level of distress for RNs and RTs. For a subset of providers, this distress can be substantial and highlights the importance of identifying and implementing strategies to mitigate this distress to create a more sustainable and effective work force. [ABSTRACT FROM AUTHOR]