• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.1
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• pp.103-110
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• 1998

This study deals with the effective management system on the underground facilities by Geographic In-formation System (GIS). For this purpose,"Management System on the Water Supply Network by GIS in Kwangju" was analylized. Following results were obtained in this study. This system could be practically used for the inquiry of water supply and distribution pipes, check valves, pipe equipments and parcel identification numbers. Inquiry of addresses using the parcel identification numbers were effective for the database management system of the water supply facilities. The poits at issue for the performance of this study were the security and education of experts, the security of revenue source, the discord between GIS companies concerned. Establishments of GIS software technologies and database systems, and the settlement between GIS companies were required for the solution of these poits. Development of computer management systems on the water sup-ply network by GIS enabled the replacement of outworn pipes and the leakage inquiry techniques in pipes. in pipes.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.4-4
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• 1998

서울 및 서울 인근 주민들의 식수 공급을 위하여 1978년에 건설된 매설 상수배관은 전기방식 조처없이 콜탈에나벨만으로 피복된채 지하철 및 각종 전기설비가 복잡하게 산재된 서울지역에서 근 20년 유지되고 있다. 따라서 이 배관에 대한 부식 상태를 파악하는 것이 배관의 안전성 확보 및 대책수립, 배관수명의 연장, 중단없는 상수공급 동의 차원에서 매우 중요하다. 이 조사의 목적은 건설후 20년이 경과하여 노후된 매설 상수배관에 대한 기본적인 부식환경 및 피복 상태를 조사하여, 부식상태를 진단하고 향후 대책을 세우기 위한 기초 자료를 확보하는 것이다. 조사의 대상은 1978년에 건설된 서울지역 매설 상수배관 103 Km이었으며, 주요 조사 내용은 토양의 pH, 토양비저항과 같은 기초적인 부식환경조사, 전 배관에 대한 부식전위측정, 부식환경 조사로부터 판정된 부식 우려구간을 대상으로 피복손상부 탐측 및 시험굴착, 그리고 상기 조사의 결과를 검토하는 것이다. 조사 결과, 기본적인 부식환경 변수로 예상되던 토양의 전기비저항, 습도, pH는 부 식전위 및 토양종류와 상관관계를 보이지 않았으며, 상수배관 주변의 토양비저항은 대부분 8,000 ~ 10,000 ${\Omega}{\cdot}cm$, 토양 pH는 대부분 5와 6사이에 집중되었다. 전체적으로 볼 때 매설 상수배관은 예상보다 양호한 배관 상태를 유지하고 있다고 판단되나, 일부 간섭구간은 방식보완이 필요한 것으로 조사되었다. 즉 일부 간섭에 의한 미방식 지역은 배류기나 희생양극 설치와 같은 조속한 방식보완 조치가 필요하며, 과방식이 우려되는 곳은 강제배류기의 출력을 크게 낮추는 것이 필요하다. 이때 부식전위가 크게 올라가는 지점이 있으면 부근 가까운 지하철 레일과 선택배류기로 연결하는 것이 바람직하다.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.574-586
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• 2019

The purpose of this study was to investigate housing situation and residential satisfaction of foreigners in Korea, and to identify influential factors for housing satisfaction. A questionnaire survey was conducted to 132 foreigners who reside in Seoul and Gyeonggi-do. Most of the respondents were Chinese and the average age was 45.7. Over 90% of the respondents lived in a rented house and detached house was the most popular type of house. Overall score of residential satisfaction was 3.43 and it was above average. However, scores for parking lot, housing deterioration, and space planning showed the lowest level of satisfaction. Factor analysis was used to summarize the variables related to residential satisfaction and 5 factors -'space planning and organization,' 'amenities & equipment', 'community facilities,' 'near environment' and 'housing expenses'- were drawn. Among those, 'space planning and organization' was the most influential factor to residential satisfaction as the result of multiple regression analysis.

• Journal of the Society of Disaster Information
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• v.19 no.3
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• pp.490-497
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• 2023

Purpose: Since the 1990s, Korea has been making various efforts to prevent serious industrial accidents, such as implementing a hazardous risk prevention plan and implementing a process safety management system, but a series of recent major industrial accidents have shown its limitations. Therefore, this study aims to present measures to improve safety management of PSM target workplaces. Method: Investigate previous studies and cases on improving safety management at workplaces subject to PSM, seek ways to improve safety management at workplaces subject to PSM based on existing safety management, and evaluate safety management system one of the causes of accidents. Therefore, a safety education program is established to increase employees' safety awareness and understanding, and to improve the safety level. Result: Measures such as establishing an organizational culture to improve safety management of PSM target workplaces, responding to disasters, systematic safety management, replacing and strengthening old facilities, and strengthening management's firm commitment to safety were presented. Conclusion: Through this study, it is meaningful to present a systematic plan to secure safety to reduce precious lives and damage, and it is expected to be useful in considering the direction of PSM improvement for each workplace.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.35-42
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• 2019

Risk assessment and analysis for a medium-to-small sized chemical plant that manufactures a polyester resin by the process of batch-type condensation reaction was conducted using K-PSR technique which is one of the risk assessment methods used to implement the Process Safety Management System (PSM). K-PSR is a risk assessment technique developed by KOSHA to compensate for difficulties caused by the lack of infrastructure of medium-to-small sized chemical plants in the re-evaluation. To apply the K-PSR technique, the entire process of a selected chemical palnt was classified in two review sections, i.e., the condensation reaction process and the dilution/filtration process, and the potential risks of the process about these review sections were identified and classified based on the four guide-words (release, fire.explosion, process trouble, and injury). As the results of the research, refer to recommend of risk rating has been confirmed that non-destructive testing of old facilities and the preparation of LOTO procedures for the electrical equipments are necessary as specific measures to prevent the risk of release and fire.explosion. It was also shown that pressure gauges and thermometers should be installed on the hot-oil supply piping to minimize the process trouble, and exhausting hood should be installed to prevent potential injury.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.149-155
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• 2023

Photovoltaic power generation is the most familiar power generation facility among new and renewable energies, and its supply began to expand about 10 years ago, and at this point, interest in solutions and technologies for system maintenance management is increasing. In particular, it is necessary to take measures to maximize the overall efficiency of the solar power generation system, whether or not there is an abnormality in the solar power generation system, and when to replace parts. The PV inverter, one element of the photovoltaic power generation system, is a power conversion system that relies on power switching devices, and DC-Link capacitors are used according to the configuration of DC/DC converters and DC-AC inverters. These DC capacitors also affect system safety (Safety) through renewable energy facilities due to the decrease in power generation of PV inverters, power loss, and increase in harmonics (THD, total distortion of AC output current) due to aging and deterioration due to long-term use. factors can be analyzed. Therefore, in this paper, the PV inverter operating characteristics according to the DC capacitor capacity state currently operating in the photovoltaic power generation system were considered, and research contents were proposed to secure the safety and reliability of renewable energy facilities.

• Korean Journal of Construction Engineering and Management
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• v.9 no.2
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• pp.99-107
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• 2008

Rapidly increasing automobile supply rate according to improved economic level of life makes lack of parking space of apartments. Even though the initial design of parking space compiled with old regulations, it may not observe either new laws or requirement of inhabitants. Even if old apartments have no structural durability problem, outworn facilities and insufficient parking area may be a main reason for reconstruction. It causes waste of national resources and makes recycling issues. Additionally, irregularly parked cars make traffic obstruction to a fire engine and result in many fire accident victims. Parking problems of apartments are not only inconvenience but also serious safety issues. From these points of view, remodeling only for parking area expansion is necessary to avoid overall reconstruction of apartments. The purpose of this study is to suggest a retaining wall selection method for apartments underground parking lots expansion without evacuation of resident people. Effect factors to select retaining wall system are analyzed and weight values are calculated by applying AHP. One selection method of retaining wall is proposed by evaluating applicability and its sensitivity analysis is executed. This selection method is expected to help decision-making of retaining wall system selection.

• Journal of Navigation and Port Research
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• v.29 no.6 s.102
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• pp.501-508
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• 2005

The purpose of this paper is to present the alternatives for improving coostal shipping logistics system to be a logistic hub-nation with a competitive edge. For this purpose, major environmental factors in Northeast Asia and accordingly its effects are analyzed And then the effects of coastal shipping system's development strategy is analysed using Structural Equation Model and Multiple Regression Model. Research results show that three types of coastal shipping development strategy( connected transportation system, structure of coastal shipping system, governmental support policy) will contribute much to being a logistics hub-nation. From the results, some implications are derived as follows. Firstly, environmental-friendly balanced ocean-coastal transport system is required Secondly, a excusive feeder port, Ro-Ro ship & high-speed ship are necessary to establish the one-stop logistics service system Finally, governmental support policy and subsidy(tax-exempted oil & various tax benefits) are required to reactivate lagged coastal shipping system to be a logistic hub-nation with a competitive edge.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.441-449
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• 2005

The purpose of this research is to present the improvement measure of lagging behind coastal shipping system to be a logistic hub-nation with a competitive edge. For this purpose, this research tries to find out major northeast asia environment factors and accordingly the effects of its. The effects of coastal shipping system's development strategy is analysed by structural equation model and multiple regression model. Research results show that three types of coastal shipping developing strategy(connected transportation system, structure of coastal shipping system, governmental support policy) will contribute much to be logistic hub-nation. The contribution effects is increasing cargo from strengthened feeder transport system and maximizing logistic service &minimizing logistic costs. From the result, some implications are derived as follow. First, familiar environmental balanced ocean-coastal transport system is required. Second the one-stop logistic service system is necessary to build excusive feeder port, and to establish Ro-Ro ship & high-speed ship, etc.. Third, governmental support policy and subsidy(tax exempted oil & various tax benefits) are required to bring up lagging behind coastal shipping system to be a logistic hub-nation with a competitive edge.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.519-528
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• 2002

It is not a rare occasion that certain dental procedures involving tooth reduction being peformed under inadequate water cooling due to a variety of reasons. This situation could possibly inflict the critical insult to the pulpal tissue of indicated tooth. The purpose of this experiment was to study the pattern of diffusion of external heat produced during routine dental procedures into the pulpal tissue. 30 stone blocks containing three lower second primary molars were used for certain restorative procedures and the temperature of the indicated tooth surface was measured by thermography(Inframetrics 600) and further used as a baseline data for the finite element analysis model fabrication designed in order to evaluate the pattern of thermal diffusion. The ranges of highest surface temperature measured from several dental procedures under water cooling and non-water cooling were $30.8^{\circ}C{\sim}43.6^{\circ}C$ and $51.2^{\circ}C{\sim}103.4^{\circ}C$ respectively. Among procedures studied, crown preparation showed the highest value and amalgam removal showed the lowest. Comparisons between data measured under water cooling and non-water cooling conditions have shown the statistically significant difference(p<0.05). All the non-cooling conditions have shown the relatively larger increment of temperature change at the pulp horn area than the cooling conditions. The results of this study strongly indicate that the water coolant is the essential element in restorative procedures for the maintenance of healthy pulp. Further related studies involving more procedures and conditions are recommended.