• 정보와 통신
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• 제19권9호
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• pp.31-42
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• 2002

CRL (Communications Research Laboratory, Independent Administrative Institution, Japan) is developing ITS wireless communication technologies in millimeter-wave frequency region. Technologies are categorized for inter-vehicle communications (IVC) and road-vehicle communications (RVC). In this paper, system concepts and the experimental facilities are introduced. The experimental facility for inter-vehicle communications is gotten ready in 60 GHz frequency region and the experimental system for road-vehicle communications is based on RoF (Radio on Fiber) technology in 36-37GHz frequency region.

• 한국융합학회논문지
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• 제10권3호
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• pp.227-236
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• 2019

본 연구의 목적은 사회복지생활시설종사자의 대인관계기술 향상과 직무스트레스 감소를 위해 개발된 프로그램인 TSL-JSM(Job Stress Management)의 효과를 사회과학과 의생명과학적 방법을 융합적으로 적용하여 검증하는 것이다. 프로그램 효과성 검증을 위해 유사실험 설계를 활용하여 비동일 통제집단 설계를 적용하였다. 연구대상은 경남소재 사회복지법인 산하 생활시설의 종사자 중 자발적 참여자로 구성된 실험집단 7명, 비교집단 7명, 통제집단에 7명이 배정되었으며, 실험집단에는 12회기로 이루어진 TSL-JSM 프로그램을 적용하였고, 비교집단에는 12회기의 시설 종사자들의 대인관계기술 강화프로그램을 적용하였다. 최종 자료 분석은 SPSS 25.0 프로그램을 이용하여 공분산분석, 윌콕슨 순위검증을 실시하였다. 연구결과, 타집단에 비해 실험집단에서 유의미한 대인관계 기술 향상 및 직무스트레스 감소를 보였으며 의생명과학지표인 심박변이도와 코티졸의 긍정변화가 검증되었다.

• 한국가시화정보학회지
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• 제18권3호
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• pp.23-34
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• 2020

Two-phase flow and heat transfer characteristics during the reflood phase of a single heated rod in the KHU reflood experimental facility were examined. Two-phase flow behavior during the reflooding experiment was carefully visualized along with transient temperature measurement at a point inside the heated rod. By numerically solving one-dimensional inverse heat conduction equation using the measured temperature data, time-resolved wall heat flux and temperature histories at the interface of the heated rod and coolant were obtained. Once water coolant was injected into the test section from the bottom to reflood the heated rod of >700℃, vast vapor bubbles and droplets were generated near the reflood front and dispersed flow film boiling consisted of continuous vapor flow and tiny liquid droplets appeared in the upper part. Following the dispersed flow film boiling, inverted annular/slug/churn flow film boiling regimes were sequentially observed and the wall temperature gradually decreased. When so-called minimum film boiling temperature reached, the stable vapor film between the heated rod and coolant was suddenly collapsed, resulting in the quenching transition from film boiling into nucleate boiling. The moving speed of the quench front measured in the present study showed a good agreement with prediction by a correlation in literature. The obtained results revealed that typical two-phase flow and heat transfer behaviors during the reflood phase of overheated fuel rods in light water nuclear reactors are well reproduced in the KHU facility. Thus, the verified reflood experimental facility can be used to explore the effects of other affecting parameters, such as CRUD, on the reflood heat transfer behaviors in practical nuclear reactors.

• 설비공학논문집
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• 제25권4호
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• pp.194-200
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• 2013

In this study, an exhaust filter unit for removing bad smells is designed and manufactured to understand the characteristics, damages, and effects on humans and animals of bad smell substances in laboratory animal breeding facilities. Using the exhaust filter unit, a deodorization performance test using ammonia gas, as a typical bad smell in an animal breeding room, was carried out for three types of activated and impregnated charcoal filters. The experimental results showed that the pressure loss of the HEPA and carbon filter was increased with flow rate and that the average deodorization performance for the case where an impregnated carbon filter was installed was a maximum value of between 93 and 96%, with various fractional flow rates ranging from 1,500 to $3,500m^3/h$ in a laboratory animal breeding room. The experimental results will also be used for the design and manufacture of a practical and efficient exhaust filter unit to cope with bad smell problems in animal breeding facilities.

• Nuclear Engineering and Technology
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• 제52권9호
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• pp.1963-1973
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• 2020

Liquid metal-cooled reactors use various passive safety systems driven by natural circulation. Investigating these safety systems experimentally is more advantageous by using a simulant. Although numerous experimental approaches have been applied to natural circulation-driven passive safety systems using simulants, there has been no clear validation of the similarity law. To validate the similarity law experimentally, SINCRO-V experiment was conducted using Wood's metal and water for simulant of the Wood's metal. A pair of SINCRO-V facilities with length-scale ratio of 14.1:1 for identical Bo' was investigated, which was the main similarity parameter in temperature field simulation. In the experimental range of 0.2-1.0% of decay heat, the temperature distribution characteristics of the small water facility were very similar to that of the large Wood's metal facility. The temperature of the Wood's metal predicted by the water experiment showed good agreement with the actual Wood's metal temperature. Despite some error factors like discordance of Gr' and property change along the temperature, the water experiment predicted the Wood's metal temperature with an error of 27%. The validity of the similarity law was confirmed by the SINCRO-V experiments.

• 항공우주기술
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• 제5권2호
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• pp.181-187
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• 2006

본 연구에서는 PSD (POGO 억제장치) 성능 시험을 위해 구축한 시험설비에 대한 내용을 다룬다. PSD 성능 시험 장치는 공급관 전체 가진 방식과 작동 유체 가진 방식으로 구분할 수 있으며, 작동유체 가진 방식은 다시 피스톤 방식과 면적제한 방식으로 분류할 수 있다. 면적 제한 방식 가진기가 기초 연구에 적합하며, 이를 채택한 PSD 성능시험장치를 제시하였다. 가진기로는 삼각함수 형태의 섭동을 줄 수 있는 판형 가진기와 볼 밸브형 가진기가 고려되었으며, 누수 문제를 고려하여 볼 밸브형 가진기가 채택되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.2053-2058
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• 2004

The pressurized light water cooled, medium power (330 MWt) SMART (System-integrated Modular Advanced ReacTor) has been under development at KAERI for a dual purpose : seawater desalination and electricity generation. The SMART design verification phase was followed to conduct various separate effects tests and comprehensive integral effect tests. The high temperature / high pressure thermal-hydraulic test facility, VISTA(Experimental Verification by Integral Simulation of Transient and Accidents) has been constructed to simulate the SMART-P (the one fifth scaled pilot plant) by KAERI. Experimental tests have been performed to investigate the thermal-hydraulic dynamic characteristics of the primary and the secondary systems. Heat transfer characteristics and natural circulation performance of the PRHRS (Passive Residual Heat Removal System) of SMART-P were also investigated using the VISTA facility. The coolant flows steadily in the natural circulation loop which is composed of the steam generator (SG) primary side, the secondary system, and the PRHRS. The heat transfers through the PRHRS heat exchanger and ECT are sufficient enough to enable the natural circulation of the coolant.

• 한국물환경학회지
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• 제28권1호
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• pp.121-128
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• 2012

The purpose of this study is to solve the problem of nutrient removal due to rapid hydraulic retention time (HRT) variation in small size private sewage treatment facility and to have better effluent quality by using natural zeolite as a coagulant aid. The experiments were conducted by applying different conditions of HRT, coagulant, and zeolite dosages. As an experimental result, $TBOD_{5}$, TSS, and TP removal efficiencies were 64.9%, 94.5%, and 98.8% at co-injection with zeolite. Overall removal efficiencies of $TBOD_{5}$, TSS, and TP have improved 15.7, 28.7, 6.1%, respectively. This result shows that zeolite addition could improve flocculation, increase setting velocity, and thus have better treatment. Therefore the use of zeolite as a coagulant aid can be useful in small size private sewage treatment facility, where especially extra nutrient removal is required to meet the legal standard for discharge.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2011년도 전기공동학술대회 논문집
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• pp.192-192
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• 2011

For the safety of vessels sailing Marine Transport Facility announces sea route, reefs or shallow water. Photovoltaic, independent power system, installation in the general Marine Transport Facilities to be used in the marine lantern. Due to install of communications, controls, power consumption inceases. And the weather of cloudy day or rainy, generation of electricity is decrease. Recently, power system of marine facility using a hybrid generation system, photovoltaic generation system and wave power generation system. But increase of adhered shellfish inside the water column, is the cause of the reduction of efficiency. So study was conducted to Single channel AFS(Anti-Fouling system). In this paper we offer the Multi channel AFS for Marine Transport Facility and have simulated. Improve the accuracy of the research, we using the result of anode, in the experiment were actually in the buoy, is based on simulation. The experimental results is shown every anode's, in the Marine Transport Facility, ionization was conducted identically.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권4호
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• pp.458-467
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• 2018

Efforts have been made in this paper to develop the measuring device for the insulation performance of full scale NO96 LNG CCS. The facility was designed to maintain environmental conditions which are similar to operation conditions of full scale LNG CCS. In the facility, the heat sink boundary was kept cryogenic temperature by cold chamber which contains liquefied nitrogen and heat source boundary was made by external case heated by natural convection. Heat Flow Meter method (HFM) was applied to this facility, hence Heat Flux Sensors (HFS) were attached to specimen. The equivalent thermal conductivity of full scale NO96 unit box was targeted to measure and PUF of same size was used for the calibration test. Additionally, the finite element analysis was carried out to check the performance of the developed test facility and experimental results were also compared with those predicted by the numerical method.