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141.
The natural circulation of primary coolant plays an important role in removing the decay heat in Station-Black-out (SBO) accident from reactor core to decay heat removal systems, such as RVACS and PHXS cooling, for lead-based reactor. In order to study the natural circulation characteristics of primary coolant under Reactor Vessel Air Cooling System (RVACS) and primary heat exchangers (PHXs) cooling, which are crucial to the safety of lead-based reactors. A three-dimensional CFD model for the China Lead-based Research Reactor (CLEAR-I) has been built to analyze the thermal-hydraulics characteristics of primary coolant system and the cooling capability of the two systems. The abilities of the two cooling systems with different decay heat powers were discussed as well. The results demonstrated that the decay heat could be removed effectively only relying on either of the two systems. However, RVACS appeared the obvious thermal stratification phenomenon in the cold pool. Besides, with the increase in decay heat power, the natural circulation capacity of primary coolant between the two systems had a significant difference. The PHXs cooling system was stronger than the RVACS, with respect to the mass flow of primary coolant and the average temperature difference between cold pool and hot pool. 相似文献
142.
《Journal of Great Lakes research》2022,48(3):659-668
Previous studies reported coastal trapped waves (CTWs) in the Caspian Sea (CS). This study deals with the generation mechanisms, the temporal and spatial variability of CTWs in this area, and their transformations during propagation from the origin to the destination using recent measurements and high-resolution numerical simulations. CTWs are observed at all stations with periods of 2–6 days after northerly storms. The Absheron Peninsula, old Sefidrud delta, and Nur coasts were identified as the CTWs prone regions. The generation of CTWs in these locations was confirmed using numerical experiments. The propagation away from the generating location of CTWs was analyzed using a representative real wind storm. In the west part of the CS, the generation mechanism of CTWs is mainly similar to the barotropic Kelvin waves; in contrast, it is similar to the continental shelf waves in the southern shelves. The results can be used to study the contribution of generated CTWs to the transport of sediment and biological materials in all large lakes. 相似文献
143.
David Meister 《Theoretical Issues in Ergonomics Science》2013,14(1):13-21
The purpose of this paper is to suggest a number of critical theoretical issues which revolve around the relationship of the human with technology. This has two aspects: (1) the human response to already developed technology (general ergonomics); and (2) the application of ergonomics principles and data to system design (developmental ergonomics). Ergonomics research which does not focus on the human/technology relationship has little to offer ergonomics. That research must also be directed to the problem of transforming behavioural principles into their physical equivalents. 相似文献
144.
145.
使用有机溶剂萃取法(OSE),对高浓度石油污染土壤进行修复。经过精馏操作,以有效回收原油,建立脱附等温曲线,得出了石油污染物在土壤-有机溶剂两相间的迁移规律。实验结果表明,液固比在3∶1到5∶1的情况下时,能够达到较好的脱附效果。 相似文献
146.
Boron Neutron Capture Therapy (BNCT) for brain tumor treatment is under development at the Tehran Research Reactor (TRR). This paper presents all current research activities that were performed during recent years as well as the prospective of BNCT research at TRR. The theoretical and experimental investigations show that TRR has a very good potential to consider it as a pilot facility for BNCT research in the Middle East and could be facilitated for clinical applications. In this way, there are some steps and also some challenges which are described in the paper. 相似文献
147.
综述了国内外利用数值模拟技术优化设计型材挤出定型冷却系统的研究进展,指出了基于数值模拟技术的定型冷却系统的设计方法,并展望了今后的研究趋势。 相似文献
148.
149.
The number of scholarly publications on agile software development has grown significantly in recent years. Several researchers reviewed and attempted to synthesize studies on agile software development. However, no work has ranked the contributions of scholars and institutions to publications using a thorough process. This study presents findings on top publications, institutions, and scholars in the agile software development field from 2001 to 2012 based on the publication of such works in Science Citation Index journals. This paper highlights the key outlets for agile research and summarizes the most influential researchers and institutions as well as the most studied research areas. This study concludes by providing directions for future research. 相似文献
150.
《Food Control》2017
The purpose of the research was firstly, to analyze existing culture evaluation systems for commonalities and differences in research quality, applied validation strategies, and content. Secondly, to suggest a simple structure of food safety cultural dimensions to help unify the culture evaluation field. To achieve these goals, a comparison of eight culture evaluation models applied to varing degrees in the food industry was conducted. The systems were found to vary significantly in applied validation strategies but through deductive, textual data analysis, five dimensions were identified that cover elements present in all the models. Transparency is needed when using applied research methodologies to continually increase quality and trustworthiness of culture research in the food safety domain and this field would benefit from both further commonality of approach to validation strategy and structure and adoption of an overarching structural framework. 相似文献