• 산업경영시스템학회지
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• 제5권7호
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• pp.9-15
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• 1982

The rectilinear-distance location problem combines the property of being a very appropriate distance measure for a large number of location problems and the property of being very simple to treat analytically. An obvious question to be asked at the optimal point which is obtained by the rectilinear distance method is, "what if the point is not available as a location site\ulcorner." The point may, for example, be inaccessible or may coincide with the location of another structure, a river, or a municipal park. In this case, one approach that may be employed is to construct contour lines (also called iso-cost or level curves) of the cost function. Contour lines provide considerable insight into the shape of the surface of the total cost function as well as a useful means of evaluating alternative locations for the new facility. But, when there is an obstacle which divides the application area into two. The optimal location(which is acquired by the rectilinear distance method) is not coincide with the minimal cost point and the contour line is occasionally of no use, this paper shows the method of finding a way to decide an optimal point of single facility location in this case.this case.

• 한국측량학회지
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• 제25권1호
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• pp.69-75
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• 2007

The information in physical planning field shows the socio-economic potentials of land resources while cadastral data does the physical and legal realities of the land. The two domains commonly deal with land information but have different views. Cadastre has to evolved to the multi-purpose ones which provide value-added information and support a wide spectrum of decision makers by mixing their own information with other spatial/non-spatial databases. In this context, the demands of data exchange between the two domains is growing up but this cannot be done without resolving the heterogeneity between the two information applications. Both of either discipline sees the reality within its own scope, which means each has a unique way to abstract real world phenomena to the database. The heterogeneity problem emerges when an GIS is autonomously and independently established. It causes considerable communication difficulties since heterogeneity of representations forms unique data semantics for each database. The semantic heterogeneity obviously creates an obstacle to data exchange but, at the same time, it can be a key to solve the problems too. Therefore, the study focuses on facilitating data sharing between the fields of cadastre and physical planning by resolving the semantic heterogeneity. The core job is developing a conversion mechanism of cadastral data into the information for the physical planning by DB coupling techniques.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1726-1735
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• 2008

Seoulmetro has operated the air cooling equipment for 57 stations to improve services focused on our customers who use Seoulmetro during the summer season and has established every year. However, a new set of problems has arisen with the cooling tower to support a heat exchange of cooling water. The most important matter is loss of efficiency in the cooling tower. The leading cause of this problem is that we use an indoor type. As the cooling tower room is located in the underground of the city because of the residents near the station. Therefore It is difficult to establish the cooling tower on the ground. But it is unsuitable for the location requirements of the underground type because it has a limited space to set up the air cooling equipment, for example, the cooling tower and a ventilating opening. As a result of such an unfavorable condition, the cooling tower doesn't work efficiently and the warmth of cooling water because of insufficiency of a heat exchange and a refrigerator's technical obstacle such as a high-temperature and a high-pressure has arisen. To prevent this situation, the operator tend to reduce refrigerant. Accordingly, the efficiency of the air conditioning is getting lower and lower. Study wishes to analyze the matter to improve indoor cooling tower efficiency and recommend a best practice for a person who manage the establishment.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.493-498
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• 2009

Recently, the number of complex construction projects, such as high-density development and long-span mega structure construction, has been increasing globally. Therefore, the construction duration has become an even more important factor for success. Nevertheless, in domestic residential construction projects, it usually takes more time than twice as much as North American cases. The long construction duration causes a number of problems, for example growth of financial costs, fall in productivity, and weakness of competitiveness. If the framework construction duration can be shortened to 3 ~ 4 days, then it is also expected to complete the finish work of building in shorter duration, be led to reduce the entire construction duration, and eventually to save a great deal of indirect costs. For shortening the construction duration, previous researches pointed out that the development of simplified plan design should precedes. But, in reality, lack of experience of new design and innovative techniques tends to be the obstacle to wide adoption of the simplified plan design in construction fields. In this paper, a simplified structural plan design is proposed, and the construction cost is quantitatively compared between when traditional construction technique is applied to the traditional plan and when the duration-shortening key technique is applied to the developed plan.

• 한국시뮬레이션학회논문지
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• 제19권4호
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• pp.1-9
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• 2010

본 논문에서는 여객선의 승객 비상 탈출 시뮬레이션을 구현하였다. 승객의 행동에 미치는 요인 중 연령, 성별을 고려하여 승객 개인의 보행 속도에 반영하는 속도 기반 모델을 사용하였다. 승객들의 집단 이동을 구현하기 위해 플로킹 알고리즘을 적용하였다. 장애물과의 충돌 회피 및 승객 간의 위치가 겹치는 현상을 방지하기 위해 페널티 보행 속도를 도입하였다. 이 알고리즘을 이용하여 여객선의 승객 탈출 규정인 IMO (International Maritime Organization) MSC (Maritime Safety Committee) Circ.1238에서 정의한 11가지 시험 문제에 적용하였다. 시험 문제를 통해 승객의 위치가 겹치는 현상이 없이 시뮬레이션 되는 것을 확인하였다.

• Advances in environmental research
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• 제12권2호
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• pp.95-111
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• 2023

Pollution, climate change, and waste accumulation are only some of the new problems that have arisen because of the exponential population growth of the past few decades. As the global population expands, managing municipal solid trash becomes increasingly difficult. This is by far the most difficult obstacle for governments to overcome, especially in less developed nations. The improper open dumping of trash, which is causing mayhem across the country, has two immediate effects: it contaminates groundwater and surface water. Air pollution and the accumulation of greenhouse gases are both exacerbated by the release of methane and other harmful waste gases. Leachate from the landfill leaks underground and pollutes groundwater. In most cases, leachate moves into the groundwater zone and pollutes it after forming in association with precipitation that infiltrates via waste. This has far-reaching effects on people's health and disturbs the natural environment. This review article critically examines the current state of Solid Waste Management (SWM), addressing both the highlighted concerns and the government management solutions that have been put in place to address these issues. In addition, the constraints, and difficulties that India will face in the future in terms of solid waste management and the role of models for such a system are discussed.

• 무역상무연구
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• 제68권
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• pp.1-21
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• 2015

The purpose of this study is to propose a new mechanism for the global transmission of electronic trade documents and to promote them using it. Trade settlement methods are changed from L/C bases to non-L/C bases and in particular, the telegraphic transfer is dramatically increased since mid 1990. But the status of transmission of electronic trade documents still rely on the letter of credit and bill of lading. So it need to change the process of transmission of electronic trade documents utilizing non-negotiable sea waybill instead of bill of lading. In this study, I pointed out two problems as obstacle factors in global transmission of electronic trade documents. First is the system connection problem between domestic and foreign banks and second is the electronic right transfer problem in the bill of lading. Electronic bill of lading has already been made, but are not used and e-Nego has also not been activated under the above issues. Therefore, it should be solved previously the above problems for the global transmission of electronic trade documents under the letters of credit. However, in transactions of transfer, it does not need the inter-bank connection and also does not occur the electronic right transfer problem of bill of lading if using the non-negotiable seaway bill instead of bill of lading. In this paper, I recommend the global transmission strategies of e-trade documents using the non-negotiable sea waybill in transactions of transfer. Hopefully, I expect the activation of global transmission of e-trade documents through the utilization of electronic non-negotiable sea waybill as suggested by this study.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.352-355
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• 2006

As the stainless steel has good corrosion resistance, mechanical property and ease of manufacture, it has been studied as the candidate material of metallic bipolar plate for automotive PIMFC. But, metal is dissolved under fuel cell operating conditions Dissolved ions contaminate a membrane electrode assembly (MEA) and, decrease the fuel cell performance. In addition, metal oxide formation on the surface of stainless steel increases the contact resistance in the fuel cell. These problems have been acted as an obstacle in the application of stainless steel to bipolar plate. Therefore, many kinds of coating technologies have been examined in order to solve these problems. In this study, stainless steel was coated in order to achieve high conductivity and corrosion resistance by several methods. Contact resistance was measured by using a tensile tester and impedance analyzer Corrosion characteristics of coated stainless steel were examined by Tafel-extrapolation method from the polarization curves in a solution simulating the anodic and cathodic environment of PEMFC. Fuel cell performance was also evaluated by single cell test. We tested various coated metal bipolar plate and conventional and graphite were also tested as comparative samples. In the result, coated stainless steel bipolar plate exhibited better cell performance than graphite to bipolar plate.

• 정보관리학회지
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• 제24권1호
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• pp.165-186
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• 2007

본 연구는 공공기록물 중 대다수를 차지하고 있는 정부저작물의 이용 활성화를 위하여 저작권의 문제를 다루었다. 미국과 영국의 저작권법에서 정부저작물에 대한규정 및 정책을 국내 저작권법의 규정과 비교 분석하였다. 그 결과 국내의 저작권법이 이들 두 나라에 비하여 정부저작물에 대한 보호를 더 폭넓게 함으로써 이용에 장애가 되고 있음을 발견하였다. 또한 정부저작물 생산기관인 각국의 정부웹사이트와 국가 대표 기록관의 저작권 규정과 관리 현황을 조사한 결과 국내의 정부웹사이트와 기록관이 기록정보 서비스에 더 제한적임을 발견하였다. 이러한 문제점을 해결하기 위하여 본 연구는 국내의 저작권법에서 정부저작물에 대한 정의를 추가하고 관련 규정을 수정하고, 정부기관에서는 이미 정부에서 개발한 정보공유라이선스를 각 부처의 저작물에 적용할 필요가 있음을 제안하였다.

• 전자공학회논문지SC
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• 제48권6호
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• pp.34-42
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• 2011

USN환경에서 다양한 정보 수집을 위해 배치된 수많은 센서노드들의 배터리를 일일이 교체해 주는 것은 많은 시간과 비용이 소요된다. 이를 해결하기 위한 방안으로 본 논문에서는 센서노드 배터리 충전용 전력획득모듈을 제안한다. 센서모듈이 환경 정보를 센싱하고 정보를 전송하는데 소모하는 전력과 자연 방전되는 배터리 전력을 보충하기 위해, 전력전송모듈에서 전송한 RF 전력을 획득모듈에서 효과적인 획득 및 효율적인 전력관리를 통해 배터리에 충전한다. 획득된 전력은 배터리 전력을 일정한 레벨로 유지시켜 센서노드의 배터리 교체 주기를 반영구적으로 늘림으로써 USN 산업의 신뢰성과 적용가능성을 높이고 USN 산업 활성화에 기여할 수 있다. 본 논문에서는 RF 무선전력전송 시스템을 이용하여 전력전송/획득모듈간 5 m의 거리에서 입사된 10 dBm의 전력을 4.2 V의 1 mA 이상의 전류로 센서노드용 리튬폴리머 배터리에 충전하는 실험을 거쳐 시스템을 검증하였고 센서노드의 배터리 소모전류와 센싱정보 송신주기를 무선으로 충전할 수 있는 전류량과 비교하였다.