• 한국시스템다이내믹스연구
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• 제6권2호
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• pp.25-35
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• 2005

This paper describes the mechanism for new investment to appear in waves of boom and bust causing alternative periods of over and under supply of electricity in Korean market. A system dynamics model was developed to describe the dynamic behavior of new investment in Korean market. The simulation results show the boom and bust cycle in the new investments. When the market price is high, investors decide to build new power plants. However, it takes some delay time to complete new power plants. When the new power plants are being added into the grid, the supply increases and the wholesale price begins to decrease. This causes the cancellation of new power plant or delay the construction. This mechanism causes the boom and bust cycle in new investment.

• 한국수소및신에너지학회논문집
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• 제30권2호
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• pp.163-169
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• 2019

This study is a research to compare efficiency of new cooling system (chiller, pre-cooler) to that of the conventional system at the hydrogen refueling station (HRS). This study includes contents for thermodynamic comparison of cooling system for HRS and comparison of pros and cons of its components. So It is to establish design concept of cooling system of HRS supplying with fuel cell electric vehicle (FCEV). HRS is charging high pressure H2 (700 bar) to FCEV. However cooling system is need to prevent temperature rise in tank. This cooling system consists of pre-cooler and chiller system.

• 한국철도학회논문집
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• 제9권4호
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• pp.473-481
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• 2006

This study attempts to estimate economic benefits in terms of cost sayings and qualitative effects resulting ken implementation of new vehicle maintenance information system. It is widely expected that the effect of new vehicle maintenance information system will be significant in cost savings by information sharing and electronic documentation. To evaluate the economic feasibility of new system implementation, the study conducted seven subsystems case studies on the vehicle maintenance information system of Seoul Metro. Economic benefits are estimated by measuring the time savings, in turn, are calculated into cost savings by multiplying the average wages per hour of employee. The result of case study showed that over the 20 billion Won will be saved owing to new vehicle information system implementation. In conclusion, this study will contribute to the field of practices for the most, in evaluation of the economic benefits resulting from new information system implementation in the railway organization.

• 정보기술과데이타베이스저널
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• 제1권2호
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• pp.103-125
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• 1994

In this paper, we introduce a new main memory storage system called FLASH that is designed for real-time applications. The FLASH system is characterized by the memory residency of data and a new fast and dynamic hashing scheme called extendible chained bucket hashing. We compared the performance of the new hashing algorithm with other well-known ones. Also, we carried out an experiment to compare the overall performance of the FLASH system with a commercial one. Both comparison results show that the new hashing scheme and the FLASH system outperforms other competitives.

• Spatial Information Research
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• 제6권1호
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• pp.47-63
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• 1998

인터넷 GIS란 인터넷에 GIS기법을 접목하여, 인터넷 환경에서 GIS서비스가 가능하도록 인터넷 상에서 구축된GIS를 말한다.인터넷 GIS는 동적 클라이언트/서버 컴퓨팅 환경에서 웹을 통해 공간 데이터에 대한 검색 및 분석을 가능케 한다. 본 논문에서는 강남구를 사례로 GIS를 이용한 새주소관리시스템 및 인터넷 GIS를 이용한 새주소 안내시스템 개발 사례를 소개한다. 새주소란 우리나라의 지번을 토대로 한 현행 주소체계가 갖고 있는 문제점을 보완하기 위해 도로방식에 의해 주소를 새로이 부여하는 것으로서 도로를 중심으로 도로명과 건물번호를 체계적으로 부여하는 제도이다. 새주소 관리시스템이란 도로의 신설, 건물의 신축, 소멸등에 따른 주소의 변화를 관리하기 위해 GIS를 이용하여 개발한 시스템이다. 새주소 안내시스템이란 새주소 관리시스템을 인터넷 상에서 구축하여 모든 사람에게 지리정보 및 주소에 대한 안내를 제공하는 시스템이다. 새주소 안내시스템은 GIS데이타의 공유와 통합환경에서 GIS구축의 효율성을 증진시키고, 시스템 구축에 따른 파급효과를 극대화할 수 있을 것으로 예견되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.419-421
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• 2002

This paper presents a methodology for the application of Unified Modeling Language (UML) to develop the new load management system. Development of new load management system in competitive electricity market is very complex since it requires too much data of power system. For the efficient and flexible design to develop of new load management system, a UML approach in applied which is composed of a class diagram, package diagram using Rational Rose Unified Process.

• 상하수도학회지
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• 제34권2호
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• pp.105-114
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• 2020

In this study, based on the System Dynamics (SD) methodology, the interrelationship between the factors inherent in the operation of the New Technology Certification System (NTCS) in Korea was identified by a causal map containing a feedback loop mechanism in connection with 'new technology development investment', 'commercialization of new technology', and 'sales by new technology'. This conceptualized causal map was applied to the simulation of the operations of the New Excellent Technology and Environmental Technology Verification System (NET&ETV) run by the Ministry of Environment among various NTCSs in Korea. A SD computer simulation model was developed to analyze and predict the operational performance of the NET&ETV in terms of key performance indices such as 'sales by new technology'. Using this model, we predicted the future operational status the NET&ETV and found a policy leverage that greatly influences the operation of the NET&ETV. Also the sensitivity of the key indicators to changes in the external variables in the model was analyzed to find policy leverage.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.268-276
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• 2004

As recent demands for cold rolling oil for steel, not only better lubricity, but cost reduction and improvement of work environment are increasingly required. In order to respond these demands, Nihon Parkerizing has developed rolling oils with completely new emulsification system. Comparing with conventional oils, the new system indicates better iron fine removability to maintain oil concentration, due to better iron fine dispersion, and superior mill stain resistance by spray stain test.

• 한국정밀공학회지
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• 제24권8호통권197호
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• pp.81-88
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• 2007

This paper presents the development of a new inchworm actuation system using the shearing deformation of the piezoelectric actuators. In this new actuation system, piezoelectric shearing/expanding actuators, an inertial mass and an advanced preload system are configured innovatively to generate the motion of an inertial mass. There are two modes in the new actuation system: (1) stick mode, and (2) clamp mode. In stick mode, the deformation of the piezoelectric shearing actuators drives an inertial mass by means of the friction force at their contact interface. On the other hand, in clamp mode, the piezoelectric expanding actuators provide the gripping force to an inertial mass and, as a result, eliminate its backward motion following the rapid backward deformation of the piezoelectric shearing actuators. To investigate the feasibility of the proposed new actuation system, the experimental system is built up, and the static performance evaluation and dynamic analysis are conducted. The open-loop performance of the linear motion of the proposed new actuation system is evaluated. In dynamic analysis, the mathematical model for the contact interface is established based on the LuGre friction model and the equivalent parameters are identified.

• 한국환경복원기술학회지
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• 제3권4호
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• pp.1-10
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• 2000

This study aims at the new design system development of landscape architecture structures, as soundproof wall using reinforced soil block. This structures, that is new soundproof wall system, have to be maintained stability on acting critical wind load, which is combined exist soundproof wall system and soundproof wall system using environmental green stone block. To the harmony of this system, the post block, so-called landscape block or cast block, is manufactured. It's possible to stand of the post bearing system combined with post-pile and post block. Through the comparison with a serious code for the acting wind load on the soundproof wall, the reasonable wind load could be calculated. Also, the mechanical stability on the green stone block was checked by the Lab. tests based on the UBC (Uniformed Building Code). Because the critical height of soundproof wall system using green stone generally was restricted, the new system demands to combination of the exist system and the new system. For the stability analysis of them, the utility program, SAP2000, was used. And, a semi-auto program on the design system of the new soundproof wall using green stone was developed, which can be easily use because of the simplification.