A RESOURCE-CONSTRAINED JOB SHOP SCHEDULING PROBLEM WITH GENERAL PRECEDENCE CONSTRAINTS

Ahn, Jaekyoung 한국경영과학회 1993 經營 科學 Vol.10 No.1

In this paper, a rule for dispatching operations, named the Most Dissimilar Resource (MDR) dispatching rule is presented. The MDR dispatching rule has been designed to maximize utilization of resources in a resource-constrainedd job shop with general precedence constraints. It shown that solving the above scheduling problem with the MDR dispatching rule is equivalent to multiple solving of the maximum clique problem. A graph theoretic approach is used to model the latter problem. The pairwise counting heuristic of computational time complexity O(n^2) is developed to solve the maximum clique problem. An attempt is made to combine the MDR dispatching rule with the existing look-ahead dispatching rules. Computational experience indicates that the combined MDR dispatching rules provide solutions of better quality and consistency than the dispatching rules tested in a resource-constrained job shop.

An Integrated Production Management Model for a Manufacturing System

JaeKyoung AHN 대한산업공학회 2003 산업공학 Vol.16 No.1

Data envelopment analyses on evaluating efficiencies of satellite communication and broadcasting R&D outcomes in Korea

Jaekyoung Ahn,Do-seob Ahn,Bon-Jun Ku 통신위성ㆍ우주산업연구회 2008 한국위성정보통신학회논문지 Vol.3 No.2

Traditionally R&D evaluation has been performed by experts who can understand the contents of the study area very well. Recently extensive application of quantitative evaluation methods have been attempted for introducing the administrative management system that poses greater importance on records and results. More objective reviews on the R&D outcomes are called for gaining public supports. In this paper a bibliometrical analysis is to be performed to evaluate satellite communication and broadcasting public R&D outcomes for last 7 years. Data envelopment analysis method is selected for evaluating the efficiencies of multiple outputs (papers, patents, royalties, technology transfers) where multiple inputs (number of researchers and R&D expenses) are given. R&D ou tcomes from 22 research institutes are being compared and satellite communication and broadcasting R&D efforts turn out to be highly efficient.

차기 위성 개발의 경제성 효과분석

안재경(Jaekyoung Ahn),안도섭(Doseob Ahn),구본준(Bonjun Koo) 한국통신학회 2010 한국통신학회 학술대회논문집 Vol.2010 No.6

현재 미국, 일본, 중국 등 위성선진국을 중심으로 위성개발 경쟁을 통한 우주영토 확대가 시도되고 있으며, 특히 위선 궤도 및 주파수는 경제적인 가치가 매우 높아 선전경쟁이 치열한 실정에 있다. 우리나라에서도 위성관련 연구개발을 시작한 이래 최초로 우주인증 통신탑재체의 국산화를 추진하고 있는 통신해양기상위성의 발사가 곧 예정되어 있다. 본 고에서는 세계적인 기술 및 서비스 조류에 따라 S 대역 중계가 등을 탑재한 차세대 위성개발의 경제성 효과를 분석하고자 한다. 이를 위해서 차세대위성으로 제공 가능한 서비스를 고찰하고 특히 민간에서 제공 가능한 서비스에 대한 경제성을 분석하여 위성개발의 타당성을 객관적으로 평가한다. 분석결과 민간과 정부가 공동개발하여 활용하는 것이 경제적으로 적절하다는 결론을 도출하였다.

M&S기법을 활용한 장보고Ⅱ급 잠수함 수명주기비용 추정

안재경(Jaekyoung Ahn),최봉완(Bongwan Choi),이용규(Yongkyu Lee) 대한산업공학회 2010 산업공학 Vol.23 No.3

With the development of science and technology, modern submarines are equipped with high technology devices and multi-functioned precise armaments, consequently, acquisition cost as well as maintenance cost of the submarines are getting higher and higher. However, tight defense budget forces navy to significantly reduce military operating and maintenance costs. In this study, the maintenance and operating costs of submarine Jangbogo-Ⅱ are estimated through M&S (Modeling and simulation) methodologies in order to reasonably and consistently work out the requirement verification system of Jangbogo-Ⅱ. The maintenance and operating costs of Jangbogo-II along the next 25 years are estimated as 312.65 billion won via engineering analysis methods while 312.69 billion won from PRICE Model, which shows only 0.04 billion won differences as a whole. This study is expected to be able to provide meaningful decision making data for not only short and/or mid term operating planning but military budgeting.

차기 개인휴대 방송통신위성 개발 타당성 분석

안도섭(Doseob Ahn),안재경(Jaekyoung Ahn),박동철(Dong-Chul Park) 한국통신학회 2009 한국통신학회 학술대회논문집 Vol.2009 No.6

한국의 水資源과 用水의 節約 및 再活用

安秉基,盧載卿 忠南大學校 地域開發硏究所 1996 地域開發論叢 Vol.8 No.-

The water resources per capita in Korea was decreased below 1,000㎥ in 1990 and the World Bank categorizes Korea as one of the water stressed countries. It seems that water shortage will be a nation wide problem in the beginning of 21C even though the 6 planned dams including the Namgang Dam and Yongdam Dam already under construction are constructed completely. Therefore the water conservation and reuse will be an urgent and hot issue in the very near future. In this study the various statistics on water resources and quality management were studied to extract the suggestions for saving water and for reusing water as follows : 1. The amount of property loss from flood was increased from 126.4 billion won per year in 1970's to 339.5 billion won per year in 1980's. In 1995 it was 600.9 billion won and the loss rate is showed to be increased continuously. Therefore it is required to make an effort to increase food production from increasing the rate of river conservancy of 61.1% and from increasing the rate of land use. 2. The mean of the total water resources per year is 126.7 billion ㎥ in Korea. Of this the total of water use is 29 billion ㎥(23%) of which domestic water is used 15.4 billion ㎥(18%), industrial water is used 2.6 billion ㎥(9%), agricultural water is used 15.4 billion ㎥(53%), and river preservative water is used 5.7 billion ㎥(20%). But the rates of various water use are required to be adjusted through water saving and water reuse. 3. The demand of domestic water is increased yearly from the growth of population, the improvement of living standard, and the extention of cities. The water supply per day per capita was increased 1.59 times from 256 liters in 1680 to 408 liters in 1994. On the other hand, the discharge of wastewater per day per capita was increased 1.80 times from 180 liters in 1980 to 324 liters in 1994. The pattern of living is showed to be directed to water pollution from the fact of that the increase rate of wastewater supply is higher than that of water supply. 4. The water supply per day per capita is planned to increase to the level of 440 liters in 2001 year. But it is considered rational to adjust low to the level of 300 liters as the developed countries are saving water. 5. It is required to raise the rate of water use from the level of sales cost to the level of production cast. From doing this, the amount of debt of 2,843 billion won have to be reduced. Thus the waste of water use will be diminished and the investment fund will be provided for the facilities of water resources. 6. It is required that agricultural water use be saved from the application of drip irrigation to upland. 7. Industrial water is used usually in the process of cooling and manufacturing. Therefore it is required to use water of little quantity and to reuse water from the design of factory in which the manufacturing is satisfied to the level of water quality.

위성/무선 연동인터넷 서비스 경제성 분석

안재경,송미자 서울産業大學校 2005 논문집 Vol.54 No.4

인터넷을 기반으로 하는 IT의 눈무신 발전과 더불어 언제, 어디서나, 시간과 장소에 구애받지 않고 인터넷을 사용할 수 있도록 하는 사회적 요구가 구체화 되고 있다. 이러한 요구에 부응하고자 국내에서는 200km 이상의 빠른 속도로 이동 중에 있더라도 초고속인터넷이나 방송 서비스를 제공할 수 있는 위성/무선통신 연동 초코속인터넷 시스템기술을 개발하고 있다. 본 연구에서는 위와 같이 개발된 연동시스템을 국내 고속철도(KTX)에 적용하여 서비스를 제공할 때, 관련 시설투자에 대한 경제적 타당성을 검토하고자 한다. 경제성 분석을 위해 현재 유럽에서 이미 제공되고 있는 고속철도 인처넷서비스를 조사하였고, 국내 고속철의 특성을 감안하여 필요시설과 장비의 항목별 비용분석을 수행하였다. 해외 사례와 비행기 등의 다른 운송수단에서 예상되는 수요 및 요금 수준에 근거하여 고속철도 인터넷서비스 매출을 시나리오별 산정하여으며, 각각에 대한 순현재가와 수익률을 도출하였다. 본 연구의 결과를 토대로 하여 위성/무선통신 연동 시스템 기술 개발에 대한 경제적 타당성을 도출할 수 있으며, 서비스 제공 시 마케팅자료로 활용할 수 있을 것이다.

자동창고시스템의 표준화 방향에 대한 연구

김지표,안재경,김종화 서울産業大學校 1998 논문집 Vol.47 No.1

This paper proposes a general guideline for developing standards on the AS/RS(Automated Storage and Retrieval System) that have already been implemented in a machine tool company. a member of G7 CIM project. An attempt is made at deriving the AS/RS standards that are not only easy to be implemented but also sure to be realized. First, the current state-of-the art for the relating standards and technologies is thoroughly reviewed and the domestic AS/RS suppliers and users are investigated through the personal interview and data survey. Then, the standards items that have to be considered are defined, and described in more detail. Finally, propagation effects and practical applications resulting from the AS/RS standardization are discussed.

공공데이터를 이용한 G2B 전자상거래 시장수요예측

박현기(Hyunki Park),안재경(Jaekyoung Ahn) 한국정보기술학회 2014 한국정보기술학회논문지 Vol.12 No.10

In this paper, an ARIMA based demand forecasting program has been implemented by utilizing public data on G2B e-commerce at public procurement service. Recently, there has been growing interest in research and use of public data. However, it is found that few studies proposed systematic procedures for collecting, processing, and analysing the public data. There also have been limitations on grasping the attributes of the public data, extracting them for researchers’ purpose and applying the right methodologies. This study presents a series of procedures for redefining and extracting the public data, and attempts to forecast the market sizes in each segment using the ARIMA model. This paper also sheds light on utilizing the public data in the area of demand forecasting by programming the whole processes where unit root test, model identification, model estimation, and model diagnostic checking are automatically to be done. As a result of the analysis, MAPE values fall into 3.90%~24.47%, which shows that the ARIMA model implemented in this paper is working well.