• 한국실내디자인학회논문집
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• 제24권1호
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• pp.197-206
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• 2015

The purpose of this study is to analyze characteristic interior spaces for TV news center studio. Based on eight channels including public and comprehensive programming broadcasting stations the method for this research is to make differentiate existing relevant literature by creating analysis items for interior spaces through various case studies as well as find out characteristics of spatial forms, colors, materials, decorations, and etc. The conclusions are as follows. Firstly, spatial form of desk and ceiling are similar shapes but floor and wall are different comparing with public and comprehensive programming broadcasting stations. Secondly, preferred color for floor and ceiling is black, for wall and desk are blue and gray. Thirdly, various materials are preferred between public and comprehensive programming broadcasting stations. Fourthly, Flat and elevated floors are preferred as well as space and logos of broadcasting station are preferred for background images as decoration elements. Lastly, Soffit ceiling, desk accommodating more than 4 people, spotlight for public broadcasting stations, and architectural lighting for comprehensive programming broadcasting stations are preferred.

• 한국유체기계학회 논문집
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• 제17권6호
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• pp.84-88
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• 2014

A long term passive cooling system is considered as the most important safety feature for the nuclear design after the Fukushima Daiichi nuclear power plant accident in 2011. The conventional active pump driven safety systems are not available during a station Black Out (SBO) accident. The current design requirement on cooling time of the Passive Auxiliarly Feedwater System (PAFS) is about 8 hours only. To meet the 72 hours cooling time, the pool capacity of cooling water tank should be increased as much as 3~4 times larger than that of current water cooling tank. In order to extend the cooling time for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility of the combined passive air-water cooling system. The current pool capacity of water cooling system is preserved, and the cooling capability is extended by an additional air cooler.

• 대한인간공학회지
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• 제32권1호
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• pp.37-45
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• 2013

Objective: This study describes the change of operator performance in drastic change of illumination level, and proposes an alternative method to cope with it. Background: The control standard of illumination for nuclear power plants(NPPs) is based on the set of limit criteria for maintaining a specific illumination level. However, there is a possibility to cause human errors according to the psychological and physiological influences to operators in the situation of drastic change of illumination such as SBO(Station Black Out), so a basic study is necessary to review the current approach. Method: We assessed the visual fatigue, subjective work load and task performance according to the three illumination situations(Normal Illumination, Emergency Illumination, and Drastic Change of Illumination). Result: Research finding shows that there are not significant differences in task performance between normal illumination (1,000lx level) and emergency illumination (100lx level), only if beyond the dark adaptation limit. However, subjective work load on mental demand and visual fatigue show a potential challenge to visual performance in drastic change of illumination. Conclusion/Application: Several trials can complement this challenge in NPPs by applying 3-way communication, enhancing readability of procedures, and managing the visual factors affecting the operators' performance through a Visual Environment Management Program including visual health aspects, etc.

• Nuclear Engineering and Technology
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• 제47권4호
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• pp.443-453
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• 2015

A hybrid safety injection tank (H-SIT) can enhance the capability of an advanced power reactor plus (APR+) during a station black out (SBO) that is accompanied by a severe accident. It may a useful alternative to an electric motor. The operations strategy of the H-SIT has to be investigated to achieve maximum utilization of its function. In this study, the master logic diagram (i.e., an analysis for identifying the differences between an H-SIT and a safety injection pump) and an accident case classification were used to determine the parameters of the H-SIT operation. The conditions that require the use of an H-SIT were determined using a decision-making process. The proper timing for using an H-SIT was also analyzed by using the Multi-dimensional Analysis of Reactor Safety (MARS) 1.3 code (Korea Atomic Energy Research Institute, Daejeon, South Korea). The operation strategy analysis indicates that a H-SIT can mitigate five types of failure: (1) failure of the safety injection pump, (2) failure of the passive auxiliary feedwater system, (3) failure of the depressurization system, (4) failure of the shutdown cooling pump (SCP), and (5) failure of the recirculation system. The results of the MARS code demonstrate that the time allowed for recovery can be extended when using an H-SIT, compared with the same situation in which an H-SIT is not used. Based on the results, the use of an H-SIT is recommended, especially after the pilot-operated safety relief valve (POSRV) is opened.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.177-185
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• 2022

Hydrogen risk in the containment filtered venting system (CFVS) vessel was analyzed, considering operation pressure and modes with the effect of PAR and accident scenarios. The CFVS is to depressurize the containment by venting the containment atmosphere through the filtering system. The CFVS could be subject to hydrogen risk due to the change of atmospheric conditions while the containment atmosphere passes through the CFVS. It was found that hydrogen risk increased as the CFVS opening pressure was set higher because more combustible gases generated by Molten Core Concrete Interaction flowed into the CFVS. Hydrogen risk was independent of operation modes and found only at the early phase of venting both for continuous and cyclic operation modes. With PAR, hydrogen risk appeared only at the 0.9 MPa opening pressure for Station Black-Out accidents. Without PAR, however, hydrogen risk appeared even with the CFVS opening set-point of 0.5 MPa. In a slow accident like SBO, hydrogen risk was more threatening than a fast accident like Large Break Loss-of-Coolant Accident. Through this study, it is recommended to set the CFVS opening pressure lower than 0.9 MPa and to operate it in the cyclic mode to keep the CFVS available as long as possible.

• 한국작물학회지
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• 제31권4호
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• pp.416-419
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• 1986

본 실험은 우리나라 참깨의 단작, 맥후작별 vinyl mulching 재배하에서의 도복방지효과를 보고자 장려품종인 안산깨. 단백깨, 광산깨를 공시하여 개화초기에 75$^{\circ}$ 45$^{\circ}$의 인위도복 처리와 도복방지 처리로서 개화시에 지주를 세워 처리간의 효과를 조사했던 바, 그 결과를 요약하면 다음과 같다. 1. 개화초기에 75$^{\circ}$ 도복은 도복되지 않은 것에 비해 가장 감수정도가 커서 단작에서 75%, 맥후작에서 81% 감수되었다. 2. 개화초기의 무처리한 구에서는 단작직파에서 약간의 자연도복이 되어 18% 감수되었고 맥후작직파에서는 태풍피해로 75%의 큰 감수를 보였다. 3. 단작, 맥후작별 vinyl mulching 재배에서 개화초기에 지주를 세워 재배한 처리는 완전다수였다.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.144-155
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• 2023

The core catcher is used as a passive safety system in new generation nuclear power plants to create a space in the containment for the placing and cooling of the molten corium under various severe accidents. This research investigates the role of the core catcher in the VVER-1000 reactor containment system in mitigating the effects of core meltdown under various severe accidents within the context of the Ex-vessel Melt Retention (EVMR) strategy. Hence, a comparison study of three severe accidents is conducted, including Station Black-Out (SBO), SBO combined with the Large Break Loss of Coolant Accident (LB-LOCA), and SBO combined with the Small Break Loss of Coolant Accident (SB-LOCA). Numerical comparative simulations are performed for the aforementioned scenario with and without the EX-vessel core-catcher. The results showed that considering the EX-Vessel core catcher reduces the amount of hydrogen by about 18.2 percent in the case of SBO + LB-LOCA, and hydrogen production decreases by 12.4 percent in the case of SBO + SB-LOCA. Furthermore, in the presence of an EX-Vessel core-catcher, the production of gases such as CO and CO2 for the SBO accident is negligible. It was revealed that the greatest decrease in pressure and temperature of the containment is related to the SBO accident.

• 한국지형학회지
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• 제27권1호
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• pp.21-31
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• 2020

Planting pine trees on the coastal dunes has been carried out along the East coast as well as West coast of South Korea. Although the artificial forestation has been regarded as a good policy that help to protect the coastal area from natural disasters, but its real effect to the landscapes is still unknown. In this study, we have installed a monitoring site with an automated weather station to study requirements for dune formation and its environmental changes in Osan beach, Yangyang-Gun, Gangwon Province. We analyzed the meteorological data collected from 2010 to 2019 and vegetational changes in the study area. As a result, the wind speed is decreased by around 30% and the pine-covered area is increased by around 300m² after planting Japanese Black Pine in 2015. At present, it seems that the eolian transport of sand particle is minimal, because the dominant winds are the westerly winds which is not landward but seaward, and because the surface roughness length is about 0.5m which is similar to that in the deciduous forest.

• 한국약용작물학회지
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• 제15권3호
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• pp.199-202
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• 2007

가시오갈피에 발생하는 다양한 병해충을 분리, 동정하여 가시오갈피의 지속적인 안전재배를 위한 병 ${\cdot}$ 해충방제의 기초자료로 활용하고자 시험을 수행하였다. 가시오갈피에 발병하는 병원균을 분리동정한 결과 Phoma sp., Rhizoctonia solani, Botrytis cinerea 등 3종으로 밝혀졌으며, 병징의 특징에 따라 각각 검은무늬병, 잎마름병, 잿빛곰팡이병으로 명명하였다. 병원균에 의한 가시오갈피의 피해는 Phoma sp.에 의한 검은무늬병이 가장 컸으며, 개체별 병징의 형태나 병발생의 차이는 있었지만 6월 초부터 병반이 관찰되어 9월부터 병반면적이 30%를 넘어 계속 확대되었다. 수집균주의 배양온도별 균사생장량을 검토한 결과 균주 모두 $25^{\circ}C{\sim}30^{\circ}C$에서 생장량이 가장 많아, 여름 고온기에 많이 발생할 것으로 사료되었다. 해충별 발생시기 및 가해부위를 보면 진딧물은 6월 10일부터 관찰되어 어린 줄기를 흡즙하였고, 8월 상순에 다시 발생해 새로 분화되는 어린 화아에 집중적으로 발생하여 흡즙하였으며 노린재와 끝검은말매미충은 8월하, 6-7월에 각각 나타났으나 피해는 관찰되지 않았다.

• 한국암반공학회:학술대회논문집
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• 한국암반공학회 2007년도 특별심포지엄 논문집
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• pp.63-79
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• 2007

Several remedial works were attempted to stabilize the collapsed area of the inlet slopes of diversion tunnel, but prevention of any further movement was being only carried out at beginning stage by filling the area with aggregates and rock debris, after several cracks had been initiated and developed around the area. The extra specialty developed folding zone is consisted with highly weathered Greywacke and Black shale. The suggested solution is to improve the properties of the rock mass of failed area by choosing the optimum level of reinforcement through the increment of slope rock support design so as to control the movement of slopes during the re-excavation. The Bakun hydroelectric project includes the construction of a hydroelectric power plant with an installed capacity of 2,520MW and a power transmission system connecting to the existing transmission networks in Sarawak and Western Malaysia. The power station will consist of a 210m height Concrete Faced Rockfill Dam. During the construction of the dam and the power facilities the Balui River has to be diverted of the tunnels is 12m and the tunnel width is 16m at the portal area. This paper describes the stability analysis and design methods for the open cut rock slopes in the inlet area of the diversion tunnels. The geotechnical parameters employed in stability calculations were given as a function of four defined Rock Mass Type (RMT) which were based on RMR system from Bieniawski. The stability calculations procedure of the rock slopes are divided into two stages. In the first stage, it is calculated for the stability of each "global" slope without any rock support and shotcrete system. In the second stage, it is calculated for each "local" slope stability with berms and supported with rock bolts and shotcrete. The monitoring instrumentation was performed continuously and some of the design modification was carried out in order to increase the safety of failed area based on the unforeseen geological risks during the open cut excavation.