• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1309-1315
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• 2004

전기철도차량에서 발생하는 고조파는 인접통신선에의 유도장애를 일으키고 철도신호장애의 원인이 될 뿐만 아니라 전원계통에 유입되는 경우에는 전력용 콘덴서의 과열을 유발시키고 주요장치의 계전기를 오동작 시킬 우려가 있다. 따라서 고속철도차량에서의 각 운전 모드별 고조파 실측을 하였으며 한국전력의 규제치를 상회함에 따라 최적대안으로 부하 측에 고조파 저감설비를 기존선 각 변전소(구로, 경산, 밀양)에 설치하였다. 이와 관련하여 본 논문에서는 고조파 저감 설비를 설치하기 전과 설치 후의 고조파 발생현황을 실제 측정하여 도표화하고 얼마만큼의 저감 효과가 있는지를 비교 검토하였다.

• Nuclear Engineering and Technology
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• 제28권4호
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• pp.415-422
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• 1996

Tritium removal from tritiated heavy water in a PHWR is the most effective way in reducing workers' internal dose and radioactivity emissions from Wolsong NPP. The optimum design of the Wolsong TRF (Tritium Removal Facility) was carried out using an approximate short-cut method with an assumption that the TRF, designed to extract 8 MCi per year of elemental tritium from a heavy oater feedstream, uses Liquid Phase Catalytic Exchange (LPCE) front-end process and Cryogenic Distillation (CD) process.

• 한국환경보건학회지
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• 제36권4호
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• pp.306-312
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• 2010

This field study was performed to evaluate the efficiency of a plasma ion-operated air cleaner in temporal reduction of airborne pollutants emitted from a pig housing facility. In the case of gaseous pollutants, the plasma ion air cleaner was not effective in reducing levels of ammonia, hydrogen sulfide, nitrogen dioxide, or sulfur dioxide (p>0.05). In the case of particulate pollutants, however, the air cleaner was effective in reducing levels of particulate matter ($PM_{2.5}$ and $PM_1$) by 79(${\pm}6.1$) and 78(${\pm}3.0$)%, respectively. Unlike the case of these fine particle fractions, the reduction of total suspended particles (TSP) and $PM_{10}$ following treatment was almost negligible. In the case of biological pollutants, the mean reduction efficiencies for airborne bacteria and fungi were relatively low at 22(${\pm}6.6$) and 25(${\pm}8.7$)%, respectively. Taken together, these results indicate that in terms of air pollutants released from this pig housing facility, the plasma ion air cleaner was primarily effective in reducing levels of $PM_{2.5}$ and $PM_1$.

• 한국도서관정보학회지
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• 제54권1호
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• pp.91-114
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• 2023

본 연구는 현재까지 주목받고 있지 못한 교정시설도서관의 중요성과 필요성에 대한 인식을 적극 확산시키고, 주로 교정시설도서관에 대한 현황조사 등에 치우쳐 있는 기존 국내 연구와의 차별성을 가지면서도 향후 교정시설도서관에 관한 행정적인 개선 방향에 필요한 부분들을 살펴보고자 외국 교정시설도서관의 서비스 운영 내용을 중점으로 조사하여 분석하였다. 분석결과, 비교적 교정시설도서관 운영이 잘되고 있는 미국, 영국, 독일 등은 사회 복귀 프로그램 등을 실용적으로 운영하고 있으며 각국의 도서관협회나 지방자치단체가 교정시설도서관 활성화를 돕고 관련 전문가들이 참여하는 위원회나 조직을 구성해 정책 지원과 이슈 점검, 연구, 보고서 발행, 가이드 지침 작성 및 개정, 도서관 간 협력 등을 논의하고 실제 운영에 반영한다. 또한 민관협치를 통해 꾸준한 지원과 관심을 유지하며, 지역 공공도서관과의 연계 시스템을 잘 활용하고 있다. 그 결과 수형자의 재범사례를 줄이는데 기여하고 있다. 본 연구를 통해, 교정시설도서관 서비스에 관한 행정적인 개선 방향을 세 가지로 제안하였다. 첫째, 교정시설도서관 서비스 가이드라인이나 가이드북 제작과 배포, 둘째, 교정본부나 도서관협회 내에 교정시설도서관 전문조직 설치와 활동 강화, 셋째, 교정시설 내 법률도서관 운영을 제안하였다.

• 한국멀티미디어학회논문지
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• 제10권4호
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• pp.492-505
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• 2007

현재 국내의 시설물의 점검 및 관리 시스템은 대부분 수작업으로 이루어진다. 이런 수동적인 관리에서는 데이터베이스로의 입력이 필요하여 인력이 낭비되고 시설물의 변화에 실시간으로 대응하지 못함으로서 여러 사고를 초래하기도 한다. 하지만 사람이 일일이 체크하는 수동적인 시설물 관리에서는 이런 문제점을 완벽히 해결할 수 없다. 이 문제점들을 해결하기 위해서는 다음과 같은 조건을 필요로 한다. 첫째, 자동화된 시스템을 바탕으로 변화된 정보를 실시간으로 인식할 수 있어야 한다. 둘째, 데이터를 정확히 기록하여 점검시간의 조작 등이 발생하지 않아야 한다. 셋째, 관리자를 통한 관리가 용이하도록 이동성이 보장되어야 한다. 본 논문에서는 이러한 문제점들을 해결하기 위하여 이동성을 지니면서 여러 시설물에 관한 관리 및 점검을 편리하게 할 수 있는 이동형 RFID 시설물 관리 시스템을 설계 및 구현하였다. 이 시스템을 사용하게 되면 기존의 시스템에 비해 점검 작업의 정확성 향상과 시간을 단축시킬 수 있으며, 고장 빈도를 줄여 비용을 절감할 수 있음을 확인하였다.

• 대한기계학회논문집B
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• 제25권5호
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• pp.634-644
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• 2001

The test facility of a 1/60-scale model for train-tunnel systems has been recently developed to investigate the effects of tunnel portal shapes, hood shapes and air-shafts for reducing the micro-pressure waves radiating towards the surroundings from the tunnel exit. The present test rig has been advanced from a 1/70-scale facility at NLR in Netherlands. The NLR test rig has the two-wise guidance system that needs two ears attached on the external surface of a model train nose. Therefore, their train models have irregular nose shapes. The main characteristics of the present facility are that the train model is guided by only one wire from the compressed air launcher to the absorber parts of test facility and the wire guidance hole is located at the axial center of a train model. In the present test rig, after a train model is launched, the air jet from the launcher does not enter the tunnel model. Experimental results were compared with numerical predictions to prove the performance of the test facility.

• International Journal of Air-Conditioning and Refrigeration
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• 제9권4호
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• pp.17-26
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• 2001

Simulation was conducted using TRNSYS to evaluate the thermal performance of a facility. This facility has a condensing-type heat exchanger which is able to recover the latent energy for the purpose of reducing the heating energy in winter. The boiler and chiller are selected based on the annual peak loads and controlled to maintain the facility at the set temperature of 14~$17^\circ{C}$. Supplied energy by the boiler and recovered energy by the heat exchanger were calculated as a function of number of pass through heat exchanger, kind of fuel and hot water velocity. Simulation results show that about 20% of the total heating load can be recovered by the heat exchanger and the amount of latent heat is increasing with the number of pass. This means that the efficiency of the waste energy recovery system can be increased by using a condensing-type heat exchanger rather than a traditional sensible heat exchanger.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1625-1629
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• 2009

The new paradigm called 'Low Carbon Green Growth' involved in reducing greenhouse gas is on the rise as a critical issue worldwide. The essential of Kyoto protocol issued in 1997 is to achieve the sustainable economic growth environments by converting existing production system to eco-friendly one. The protocol imposes the liability to reduce greenhouse gas to the countries joined to it. The paradigm is directly involved in the energy consumption and environmental pollution caused by construction activities. Value Engineering which are mainly applied in the design phase in practice is a measure to improve the value of a constructed facility by analyzing and/or appraising the functions and costs of it. However, an appropriate method which assesses eco-friendliness of constructed facility has not been propose by researchers. This paper proposes a method which assesses the performance involved in eco-friendliness of constructed facility using Value Engineering (VE) in the design phase. The method estimates the environmental cost relative to the amounts of energy consumption and environmental pollution occurred over the entire project life cycle. The database called "Life Cycle Inventory DB", which stores information about the amounts of environmental pollution, is used. The algorithm which retrieves the amounts of environmental pollutions from the DB and converts them into environmental costs is developed. The algorithm is implemented into a system which quantifies the eco-friendliness of constructed facility in the design phase using VE.

• 산업경영시스템학회지
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• 제46권4호
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• pp.93-100
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• 2023

In this paper, an alternative inventory policy that trades off the bullwhip effect at an upstream facility with cost minimization at a current facility, with the goal of reducing system wide total expected inventory costs, when external demand distributjon is autocorrelated, is considered. The alternative inventory policy has a form that is somewhere between one that completely neglects the autocorrleation and one that actively utilizes the autocorrelation. For this purpose, a mathematical model that allows us to evaluate system wide total expected inventory costs for a periodic review system is developed. This model enables us to identify an optimal inventory policy at a current facility that minimizes system wide total expected inventory costs by the best tradeoff of the bullwhip effect at an upstream facility with cost minimization at a current facility. From numerical experiments, it has been found that (i) when the autocorrelation is negative, the optimal policy is one that actively utilizes the autocorrelation, (ii) when the autocorrelation is small and positive, the optimal policy is one that neglects the autocorrelation, and (iii) when the autocorrelation is large and positive, the optimal policy is somewhere between one that actively utilizes the autocorrelation and one that neglect the autocorrelation.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.418-425
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• 2022

For a commercial building, property managers play an important role in maximizing the benefit by reducing cost and increasing revenue in the operation and maintenance phase of the building. However, most of property managers are spending their time in monitoring facility managers who have little impact on cost reduction and maximization of operating profit. The industry practitioners have difficutlty in increasing the efficiency of thier work due to this work environment. In addition, both property managers(PMr) and facility managers(FMr) are dependent on the paper drawings and manuals, which can worsen the inefficiency and human errors are inevitable. This study aims to contribute to improvement of the current practice by developing a novel algorithm that autmatically links the facility information with 3D model, which can provide an efficient property management for commercial buildings.