Results 1 - 10 of 660
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[en] In this study, scaling analysis is applying to reduce air natural circulation facility, to predict the flow rate of natural circulation in the real scale RVCS. The distortion of heat transfer coefficient applying scaling analysis should be checked by comparing heat transfer coefficient obtained from experimental data. Based on these studies, we will carry out a comparative CFD analysis to validate.
[en] The objective of this study is to develop a technical assessment methodology on tip-over due to the earthquake which is expected to be major issues during the evaluation of storage cask integrity. This study has derived the equations of motion for evaluating the tipover of the storage cask, and an in-house program was developed. The tip-over and rocking motion of the freestanding dry storage cask was evaluated by the real earthquake time history. Then various variables and influences affecting the tip-over of the SF storage cask were analyzed.
[en] A nuclear reactor which is Ultimately Safe, Simple, and Cheap (USSC) must be on the top of the Top-Tier Requirements (TTR) for the H-LPRR. Safety Classification, part of a systematic safety assessment, is the starting point for reactor design. This paper presents a preliminary safety classification of HLPRR as well as the design information based on a preliminary deterministic safety analysis. A preliminary safety classification was prepared for the H-LPRR targeted on countries starting nuclear engineering based on the IAEA standards. The classification was supported by a deterministic safety analysis for the conceptual design evaluation.
[en] Molten corium concrete interaction (MCCI) which is a complex thermo-chemical phenomenon has been analyzed and studied continuously for reducing the uncertainty of the modeling. One of the issues in the MCCI phenomenon is the coolability of corium. Under the condition that the water on the upper surface of the corium layer exists, the heat transfer between the corium layer and the water has a profound effect on the overall ablation. The purpose of this paper is to identify current coolability models on the upper surface and analyze the effects of cooling mechanisms on the total energy transfer. The heat transfer by the water ingression mechanism was enhanced up to about 50 %. The enhancement effect of the heat transfer by the melt eruption mechanism was insignificant in this simulation condition. It has to be verified in various conditions.
[en] The PRIDE must maintain an inactive (argon) atmosphere due to the characteristics of processes that take place in it, such as electrochemical reduction, electrochemical refining, and electrochemical smelting. In concentrating impurities at the facility, oxygen and moisture must be lower than 50 ppm. This paper describes the work of improved exhaust damper automation in the PRIDE facility. This was a very simple but necessary task. The exhaust damper improvement will remove the disadvantage of having to manually switch the exhaust damper on or off when the exhaust system is running, and the exhaust system will operate on an increased efficiency of the exhaust fan via on the main control system.
[en] This system is composed of a linear accelerator (LINAC) X-ray source, detector arrays for converting X-rays to electronic charges, a readout circuits for collecting and amplifying signal charges, a data acquisition (DAQ) system for converting analog image signals to digital image signals, and a control unit for processing the image. Among these components, it is the detector array and the readout circuit that determine the quality of the X-ray image, that is, sensitivity and dynamic range. In this study, a 32-channel charge sensitive readout circuit was developed. The implementation of readout approach is described and the experimental results are presented. The 32-channel readout circuit for X-ray cargo inspection system was developed.
[en] There is a facility named PRIDE in KAERI for developing Pyroprocessing technology. In PRIDE depleted Uranium feed material and a depleted Uranium mixed with some surrogate material are used for performing engineering scale Pyroprocessing. When entering PRIDE, every people had to use the RFID(Radio Frequency Identification) system. But the RFID system had a lot of disadvantages. To get more specific radiation dose and data, we improved PRIDE’s access control system.) We can now strictly manage the radiation-controlled area by improving the access control system.
[en] In this study, water-air experiment is performed for preliminary study of the SWR in the PCSG. In this preliminary experiment, flow patterns are identified in situation of which air flow is injected into the downward water flow. It noted that this result not considers effect of chemical reaction. It means Pattern III can be happened in the SWR experiment in the PCSG if chemical reaction is considered. Therefore it implies that the wastage is not taken place within failed tube. It can be deduced that acoustic detector should be mounted on headers part of the PCSG and wastage in headers is considered when the SWR experiment in the PCSG is carried out.
[en] We analyzed the microstructural characteristic of hydrides in Zr-2.5wt%Nb pressure tube. The hydrogen was charged cathodically and the hydride-contained sample was evaluated using the advanced analysis methodologies. We performed a DCS (D erential Scanning Calorimeter) analysis to more quantitatively understand the thermodynamics of the hydride formation/growth process. We characterized the micrograph of hydride-contained Zr samples to estimate the microstructural characteristics of the hydrides. We investigated ects of hydrogen concentration and homogenization heat temperature on average hydride density, average length and their distributions. Those microstructural measures were quantitatively analyzed and the mechanism of the Zr-hydrides growth was discussed.
[en] Treatment of pleural metastasis consists of tube thoracostomy and pleurodesis using sclerosing agents such as talc and Viscum album. In this study, we describe the imaging efficacy of 177Lu-labeled antibody to target the CD55-expressing pleural metastatic lung cancer cells. These results suggest that 177Lu-anti-CD55 antibody has promising characteristics as a novel nuclear medicine, especially for the imaging of CD55- expressing pleural metastatic lung cancer.