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[en] The US argued for a Joint Comprehensive Plan of Action(JCPOA) without the sunset clause as it did not trust Iran to comply with the IAEA, NPT and Additional Protocol once the JCPOA was terminated. How can states overcome mistrust? This paper argues that the JCPOA must continue to resolve the issue of mistrust Continuing the JCPOA may contain the risk of Iran restarting its nuclear ambition once the sunset clause expires. This is because Iran has to allow the IAEA access to its facilities as well as implement the Additional Protocol on a provisional basis in return for incentives. Thus JCPOA will serve as a regulatory control regardless of states’ mistrust. Fostering trust and building confidence will only come once Iran displays results of implementation.
[en] The nuclear power industry has been slow to grow globally since the Fukushima severe accident. This is because energy demand is increasing due to rapid economic growth in recent years despite its low technology and the Chinese government have been keeping the active support and resources. Korea, which is trying to order a nuclear power plant, needs to keep looking at the policy direction of the neighboring countries. In this study, we will examine China's nuclear research and development policy and try to understand the current state of nuclear power in China.
[en] In accordance with the amendment of Nuclear Safety Act in 2015 and the amendment of regulation on technical standards for nuclear power facilities in 2016, accident management is legislated and the range of accident management is classified design basis accident (DBA), multiple failure accident, extreme hazards and severe accident. This paper describes the preliminary evaluation of ISLOCA for OPR1000 nuclear power plants. Preliminary evaluation of interfacing system LOCA for OPR1000 is accomplished. In the system connected to the reactor coolant system pressure boundary, it was examined whether it meets design requirements of interfacing system LOCA. We also reviewed design improvements against interfacing system LOCA vulnerabilities.
[en] Markov chain and Markov process are two common group of methods applied to analysing complex engineering systems to compute their probabilities of failure. The main advantage of Markov chain is its ability to track the evolution of the reliability of a system in time domain. Markov chain Monte Carlo (MCMC) computes the probability of failure by running many simulations through the transition matrix until the final state is reached or enough time has passed. As opposed to direct sampling, MCMC can exhibit large errors. However, it is rich because it can accommodate large set of variables. Recent developments and design requirements have pushed the limits of reliability methods like first order reliability method (FORM) and second order reliability method (SORM) to the point where new methods must be developed.
[en] The conceptual design and simulation results for automatic startup scheme for RR (Research Reactor), is presented in this study. The automation of reactor startup and operation has been studied for NPPs, but actual application to NPP was not found in literature. The proposed auto-startup logic is aimed to automate the reactor startup and operation for RRs. It includes the adjustable set of operational parameters in order to utilize the operational experience from human operator. The auto-startup scheme for research reactors has been studied. The basic design feature, aim of the logic, configuration, functions, and a simulation result for a power ascension case have been discussed and shown. Future woks include the parameterization of the other operational experience for more advanced MO design, and consideration of abnormal operation.
[en] The software V&V method used to verify the hardware characteristics was verified by adding a System on Chip (SoC) design and verification method. This approach has resulted in differences in the V&V methods and activities. In this paper, we will shed light on the V&V methods of software and FPGAs, and discuss important points in FPGA verification. FPGA is hardware, but HDL used for implementation is similar to the syntax of general programming language. Therefore, verification of the software aspect is necessary, but verification of the hardware characteristic is the most important aspect of the FPGA verification process. In order to minimize FPGA design errors, FPGA V&V should verify characteristics of the FPGA and of the signals between FPGA and its surrounding ICs.
[en] Conventional methods of radiotherapy have often been limited by physical drawbacks, use nuclides with high decay energies and short half-lives, and radionuclide loss resulting in dose to non-target tissue while circulating in the blood. To overcome these limitations, a novel approach for radiotherapy is use of parent isotopes with low energy-emitting and longer-lives of therapeutic isotopes. In conclusion, the advantage of in vivo generators is to enhance to diagnose and treatment condition with combine nuclear and chemical properties of the parent and daughter nuclides.
[en] The operational efficiency of nuclear power plants (NPPs) becomes a main technical challenge against to the many requirements from various perspectives as well as from safety concerns. Operational efficiency should be dependent on the sensing and data processing, and finally upon the decision makings conducted by the organizational staffs informed by the processed data. Many emerging technologies from data processing and business process modeling (BPM) and people analytics could support the operational efficiency and the profitability of NPPs. This research is focused to the development of a new technique and a solution for detecting operational hazards and analyzing plausible countermeasures in organizational level.
[en] In this study, using the quantum mechanical (QM) calculation based on the density functional theory (DFT), we construct a method to calculate the solution enthalpy of gaseous impurities. We test the method for O in liquid Na for validation and compare the results with experimental data. The solution enthalpy is expected to be reasonably determined with shorter time and lower cost than experiments. By the performance evaluation of several exchange-correlation functionals for liquid Na, PBE is considered to be the most suitable. The vibration analysis for a gas molecule is used to determine the thermodynamic quantities of an oxygen molecule at high temperatures, of which the results are accurate compared to the experimental data. The solution enthalpy of O in liquid Na at 600 K is evaluated. The results are to be validated, and the corrections are to be made.
[en] DIAC (Daejeon ion accelerator complex) is part of KEK's TRIAC (Tokai Radioactive Isotope Accelerator Complex), which was transferred to KAERI in April 2012 and installed. It consists of ion source, RFQ, and IH, and the specifications of each component are shown in Table I. To use accelerated beams, three beamlines are planned to be installed downstream of the accelerator, called Nano, Material, and Micro-beams, respectively. The beamlines are configured as shown in Fig. 1. The specifications of the quadrupole magnet for the achromatic operation of the Nano-beamline for DIAC have been investigated. Experimental confirmation is needed to see if the current quadrupole magnet satisfies the specifications. Based on these experiments, the whole system for the achromatic operation will be designed and prepared for user service.