The Instituto de Engenharia Nuclear (IEN) is a nuclear research facility whose main research lines comprehend non-destructive essays with thermal neutrons in biology, industry, environment and national public security. IEN is a restricted areas access composed by several laboratories, a particle accelerator and a nuclear research reactor known as the Argonauta. Viewing the accident in Fukushima has contributed to the reinforcement of the concern related to the nuclear applications, thus highlighting its negative aspects, it is important to provide information about what are the real purposes of a nuclear facility to avoiding misunderstandings created by sensational headlines. On the other hand, several researchers have proposed applications using virtual reality techniques to solve nuclear engineering related issues in recent years. Additionally, technical literature records a large number of uses of virtual reality concepts to develop simulated environments with a high degree of fidelity to their real counterparts. Therefore, this survey proposes a virtual environment that is able to simulate the visit procedure in a nuclear facility to provide information about the nature and purposes of the procedures, products and services developed in such technological centers without the access constraints found there. To do so, we used the Argonauta as case study. A group of 56 interviewees evaluated the proposed environment by means of a questionnaire composed by Likert-scale questions. Their feedback has shown that the proposed method can give a more reliable glance about the benefits of the nuclear energy thus contributing to avoid that only its negative aspects are known.
My first objective was to understand the most important aspects of decision support pro- cesses, and how these might impact my models for public participation in nuclear facility siting. There were several distinct areas I needed to explore. The first was to explore how decision support processes (with a focus on software implementations) have evolved over time, with particular interest in the role group selection and interactions can play. Sec- ondly, I needed to identify several potential models I could implement to assist decision making in public participation scenarios. The potential models I investigated were; utility theory, system dynamics and discrete event simulation (alongside considering other mod- elling paradigms seen in Chapter 4). Finally, I needed to explore how these two components tended to interact. Particularly in the past two decades where such modelling techniques were becoming more common in decision making. At this point I highlight my di ff erence in meaning between decision processes and decision structures. I use the term process when referring to the overall aim of the paradigm. Structure, however, refers to the details of how this process is applied in practice. This objective allowed me to have a strong understand- ing of the options available to me, and how to best develop my own models for decision assistance.
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The Interim Spent Fuel Storage Facility building has a storage capacity to store spent nuclear fuel from NPP Dukovany, which is 1340 t of uranium. This amount of spent fuel can be stored in 133 containers (for 84 fuel assemblies), which, with already full building of Intermediate Interim Spent Fuel Storage Facility building, will store all spent fuel generated during estimated NPP operating life. The operating life of the Interim Spent Fuel Storage Facility building will depend on construction and commissioning of underground storage facility or on review of NPP fuel cycle (system of spent fuel processing), exploitation of new technologies, etc. Between years 2006 – 2013, for which the analyses were performed, 25 containers CASTOR 440/84M is to be stored in the Interim Spent Fuel Storage Facility building (the limitation to this time period was based on a narrow link of performed analyses to a particular and approved containers, which is only known for this initial period). The container CASTOR 440/84M is designed for transport and long-term storage of spent fuel assemblies from pressurized water reactors of VVER 440 type. It consists of a thick wall cylinder body with a closing system comprising two lids (primary and secondary) and of a bearing basket located inside the body, in which the fuel assemblies are stored. The lids are fixed to the body by screws with cylinder head. Primary and secondary lids represent two independent seals of the container. Monitoring of pressure in the area between the lids allows checking of container tightness during storage. As a protection against mechanical impacts and weather conditions a protective slab is installed above the lid closing system.
Type of slope collapse mode which would be in the case of occurrence of collapse is made decision based on shaking table experiment of slope model collapse and analytical consideration of collapse behaviour using information obtained through the site investigation related to geological feature and gradient of peripheral slope of nuclear power plant. If type of slope collapse mode is the growing collapse, sliding massed soils will stop on the slope according as the earthquake shaking decreases. However, in the case of sliding down collapse mode, sliding massed soils will not stop on the slope even if the earthquake shaking decreases and they will fall down in the act of gravity. That is reason; they have fear to influence on significant structures installed in close to the slope. In this story, if occurrence of sliding massed soils to fall down cannot be denied, the following evaluation is performed.
The good agreement between numerical and experimental results must not make forbidden the difficulties in the definition of the damage index: what can be defined as failure ?, for which level of damage are designed the structures such as the nuclear facilities ? Furthermore the lack of common rules for the seismic assessment make problematic the choice of some modeling parameters such as the damping matrix, the strength of the brittle failure mechanisms, the influence of the construction details on the modeling parameters, etc…
As is expected, an increase in the number of deployed fast reactors results in an increase in the total cost of electricity, while the uranium utilization and long-term heat loading objectives show improvement. An initially unexpected feature of the observed trade-off surface, however, is the manner in which the long-term heat objective rapidly decreases for the first few fast reactors before settling at a nearly constant low value. A close examination of the VISION model reveals that this effect is due to the simple method currently used to predict the sizing, construction, and operation of the aqueous reprocessing facilities used to treat the LWR spent fuel. In this method, reprocessing facilities are built as needed such that their annual capacity will meet the maximum annual fuel demand of the FBR fleet. This fuel demand rate has a very sharp peak when the first reactor core is produced, but then quickly drops away. Because the ordering method does not predict this demand shape ahead of the time required to build the reprocessing facility, it cannot pro-actively accumulate a stock of separated material in order to spread the production rate out over a more reasonable time frame. Furthermore, once the reprocessing facility has been built, it continues to operate at full capacity until it exhausts the available supply of spent fuel. This transfers the majority of the heat-emitting isotopes from the spent fuel (waste) stock, to the separated material (resource) stock, even though there is no foreseeable use for it. In configurations approaching the upper limit of FBR deployment levels, this approach has little effect on the overall fuel cycle (apart from low utilization of reprocessing facilities). However, for configurations in which the overall FBR deployment level is well short of the maximum, this leads to significant excess storage costs and the accumulation of politically problematic separated plutonium stocks. Improvements to the VISION algorithm are not addressed in this work, as they are expected to have been incorporated into more general ongoing improvements to the VISION model.
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The implementation of seismic isolation in a nuclear facility has four potential benefits: 1) economic: reduction in capital cost, 2) increased safety: reduction in the mean annual frequency of unacceptable performance, 3) insurance: protection against increases in the known seismic hazard after construction by minimizing the effort to re-qualify and re-certify structures, systems and components, and 4) recertification: the opportunity to certify an existing NPP design for a region of higher seismic hazard. The safety benefit has been addressed in prior studies (e.g., Huang 2011a, 2011b) whereas the economic benefit is still unclear. The safety and economic benefits are explored in this study for an archetype building, described hereafter as a Generic Nuclear Facility (GNF).
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The special purpose file for new activation cross section data, JENDL/AD-2017, is being developed. This file aims at specializing the estimation of activated amounts for decommissioning of a nuclear facility. The radioactive products, to which attention should be paid, are 227 nuclides with half-lives longer than 30 days and 12 nuclides with very long half-lives. The parent nuclides were selected to be included in the file by the following criterion: (i) Nuclear reactions on the nuclides produce the radioactive products and (ii) threshold energies of their reactions are smaller than 10 MeV. Hence, the total number of nuclides is planned to be 304 from 2 H to minor actinide
Apart from Ref. , the approach of modeling the non-homogeneous atmosphere by dividing a larger volume into control volumes and using the CONTAIN code has also been used in other analyses. A simulation of atmosphere stratification in the containment of a two-loop Westinghouse-type Pressurized Water Reactor nuclear power plant is described in Ref. , where the calculated results were qualitatively similar to the experimental results from the NUPEC facility . In Ref. , the author considered a simple system, built from 4 identical cells (Fig. 3). Hydrogen was initially present only in cell 1. With a certain choice of the ratio A/L (identical for all flowpaths), the author obtained at the end of the simulation with the CONTAIN code a higher hydrogen concentration in cells 2 and 3 than in cells 1 and 4, and thus showed that atmosphere stratification can, in principle, be simulated with the approach used in this investigation.
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For development of threat scenario and establishment of nuclear forensics facility, two approaches were considered as shown in figure.1. Analytical and classical approaches which is further sub-categories leads to the origin of the sample . At first, methodology for analyzing the origin of radioactive sample is discussed and then risk assessment involves in quantifying and evaluating the nuclear aspects of KSA on embarking nuclear power program. The uncertainty propagation factor for calculating the age of radioactive sample has been defined and evaluated . This factor gives the age of the radioactive sample with time elapse along with particular radioactive nuclei that was chemically separated from its decay product.
From theoretical calculation as shielding requirement for our PET-CT facility, 11 mm Pb thickness or, 13 cm concrete thickness are found shown in Table 2. Sometimes, theoretical calculations do not meet the practical demand. This may be due to the improper concrete mixing ratio. Though Bangladesh Atomic Energy Regulatory Authority (BAERA) recommends P should be one tenth of public dose for quality assurance but in this calculation public dose ( i.e. , P = 1 mSv/yr) is used. The formula in Equation (4) is used in shielding calculation only for lead glass not for concrete walls. In this study, only imaging room wall and lead glass shielding requirement have been calculated and all other rooms such as uptake room, hot lab etc. are considered to be parallel of examination room. All walls and ceiling are made of 30.48 cm (1 foot) thick concrete with density 2.35 g∙cm −3 for more safety. Lead equivalent glass of 10 mm thickness is
Abstract. The NICA (Nuclotron-based Ion Collider fAcility) project is now under active realization at the Joint Institute for Nuclear Research (JINR, Dubna). The main goal of the project is a study of hot and dense strongly interacting matter in heavy-ion (up to Au) collisions at the center-of-mass energies up to 11 GeV per nucleon. Two modes of operation are foreseen, collider mode and extracted beams, with two detectors: MPD and BM@N. The both experiments are in preparation stage. An average luminosity in the collider mode is expected to be 10 27 cm −2 s −1 for Au (79+). Extracted beams of various
MYRRHA is now foreseen to be in full operation by 2023 and it will be operated as an Accelerator Driven Systems to demonstrate the ADS technology and the efficient demonstration of MA in sub- critical mode and will be able to be run in critical mode. As a fast spectrum irradiation facility, it will address fuel research for innovative reactor systems, material research for GEN IV systems and for fusion reactors, radioisotope production for medical and industrial applications and industrial applications, such as Si-doping. Being based on heavy liquid metal coolant technology, MYRRHA will also act as the European Technology Pilot Plant for the development of the Lead Fast Reactor.
The first section will present the overall studied facility for the photon beam inducing fissions and the delayed gamma detection set-up. The second part will be devoted to the specific developed tool, called DEGAS (Delayed Gamma Spectrum), to obtain γ spectra (including fission yields and decay data libraries, Bateman depletion equations solving - involving numerical issues and the verification of the whole procedure). At the end, we will propose an automated tool to select specific γ-ray lines ratios to detect a specific actinide in the waste package.
The nuclear physics program at the ELI-NP HPLS addresses studies of nuclear reactions of astrophysics interest in a controlled plasma environment, which will help understanding the screening effect, i.e. the reaction cross section variation due to the presence of the electron cloud around nuclei in hot plasma conditions . One laser beam will be used to create a secondary plasma target with controlled temperature and density, while another laser pulse will accelerate ions from a primary target that will impinge on short time scale, up to 1 ps, on the rapidly expanding plasma target. Plasma environment is expected to produce changes also in other nuclear observables, such as decay modes and half-lives of unstable states. Large number of free electrons, photons and highly charged ions
C(α, γ) reaction. Time projection chamber (TPC) detectors operating with low pressure gas (as an active target) are ideally suited for such studies. We review the progress of the current research program and plans for the future at the HIγS facility with the optical readout TPC (O-TPC) and the development of an electronic readout TPC for the ELI-NP facility (ELITPC). Keywords:
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The results are derived from 399 respondents. Of these 229 (57.4%) were male, 231 (57.9%). married, 229 (57.4%) educated while 31 (7.8%) were still on professional employment and only 14 (3.6%) lived in permanent houses. Cumulatively, the access rate of health care services among the elderly was 40.4%. The healthcare services were affordable 330 (82.7%) but unavailable 355 (89.0%) and unacceptable 239 (59.9%). This finding on availability and acceptability of services was corroborated by qualitative finding which established that there are no specific service tailored made for senior citizen. One KII informant candidly commented “Well as you may know this is a general facility, we strive to serve all Kenyans subject to resources. There is no services specifically designed for the elderly but we serve them with great humility and decorum”. Another KII informant echoed this sentiments- This is a public facility, my staff serve indiscriminately however the elderly deserve unique attention which are out of our scope due to competing demands. Predisposing Characteristics and enable variables
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Although there have been extensive theoretical studies on this subject, previous attempts to measure NEEC have been unsuccessful , including our own attempts  to detect the NEEC process by resonantly exciting the ground state of 181 Ta and 187 Os in plasmas generated at the Omega Facility at the Laboratory for Laser Energetics at the Uni- versity of Rochester. The limited observations of the par- allel bound-state process NEET are controversial and have been restricted to non-plasma environments [4–6]. We will overcome this challenge by inducing NPIs on highly- excited (∼1 - 5 MeV) nuclear states produced by nuclear reactions prior to their decay by spontaneous gamma-ray emission. The large density of nuclear states (≥ 10 −1 - 10 0 eV −1 ) at these excitation energies increases the prob-
The definition of the initial source term has been conducted by considering only one nuclear power unit affected by a severe accident. Note that, even if several units were affected by a severe accident, the wind cannot direct all the radioactive releases towards the EOF. To be conservative and knowing that the NPP units are similar enough (i.a. in terms of produced power) to present relatively comparable releases, the unit closest to the new EOF location has been taken into consideration.
The new research facility NICA aimed at the studying of heavy ion and polarized proton and deuteron collisions is under design and construction at the Joint Institute for Nuclear Research (JINR) since 2010 . The study of hot and dense baryonic matter should shed light on: in-medium properties of hadrons and the nuclear matter equation of state (EOS); the onset of deconfinement (OD) and / or chiral symmetry restoration (CSR); phase transition (PT), mixed phase and the critical end-point (CEP); possible local parity violation in strong interactions (LPV) ∼ [2–5]. It was indicated that heavy ion collisions at √ s NN ∼ 11 GeV