• 제목/요약/키워드: economic problem

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AMS(Advanced Manufacturing System)의 실질인 경제성 평가를 위한 수정된 경제성 평가모델의 도입과 AHP(Analytical Hierarchy Process 기법의 분석에 관한 연구 (Study on the analysis of AHP method and the introduction of modified economic evaluation model for subtantial economic evaluation of AMS)

  • 유일근;오경환
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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    • pp.335-343
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    • 1990
  • The traditional economic evaluation methods do not seem to consider derivative efforts-productivity improvement, quality improvement.-which may be occured by AMS introduction. Current evaluation methods are based on mass production with known characteristic and stable technology. Recently, expert suggest that these assumption-stable production and mass production-are realized to be a limited in substantial economic evaluation analysis. Therefore, the problem of traditional evaluation methods suggested in this thesis and decision in the case studies are derived using two complementary economic analysis methods-AHP method, modified economic evaluation model- and traditional evaluation method. After three methods are compared and evaluated in the view of practical economic evaluation, AHP method is intended to be introduced as a new economic evaluation method.

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비평활 발전비용함수를 가진 동적 경제급전문제의 교환 최적화 (A Swap Optimization for Dynamic Economic Dispatch Problem with Non-smooth Function)

  • 이상운
    • 한국컴퓨터정보학회논문지
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    • 제17권11호
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    • pp.189-196
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    • 2012
  • 본 논문은 동적 경제급전의 최적화 문제를 풀기 위해 교환 알고리즘을 제안하였다. 제안된 알고리즘은 첫 번째로, 발전단가 $C_i^{max}/P_i^{max}$가 비싼 발전기는 가동을 중지시키는 개념을 도입하여 총 요구량 $P_d$와 총 발전량 ${\Sigma}P_i$의 균형을 맞추었다. 다음으로 발전량을 $P_i=P_i{\pm}{\Delta}$, (${\Delta}$=1.0, 0.1, 0.01, 0.001)에 대해 $_{max}[F(P_i)-F(P_i-{\Delta})]$ > $_{min}[F(P_j+{\Delta})-F(P_j)]$, $i{\neq}j$이면 $P_i=P_i-{\Delta}$, $P_j=P_j+{\Delta}$로 발전량을 교환하는 방법을 적용하였다. 동적 경제급전 문제의 시험사례에 제안된 알고리즘을 적용한 결과 기존의 휴리스틱 알고리즘 최적화 발전비용을 크기 감소시켜 경제적인 이익을 극대화 시켰다.

인천 경제자유구역의 현황과 발전방향 - 중국 경제특구와의 비교를 통해 - (Status and Development Direction of Incheon Free Economic Zone - Through comparison with the Special Economic Zone of China -)

  • 서영진;박주문
    • 도시과학
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    • 제7권1호
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    • pp.11-21
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    • 2018
  • Abstract: Korea has designated free economic zones to build the foundation for national economic development by setting up special economic zones to be more competitive in cities. On August 5, 2003, the government designated Songdo, Yeongjong and Cheongna districts in Incheon as free economic zones. But while the development should have been completed nearly three years before the end of the development, the development has been slow and the population, foreign direct investment and other business results are far from the initial plan. Therefore, in this study, we will investigate the various problems occurring in the Incheon Free Economic Zone, investigate the causes of the problem, and then compare and analyze the Incheon Free Economic Zone and China's special economic zones. The two institutions share similar characteristics in many areas, but the Incheon Free Economic Zone system has yet to be settled, as the special economic zone has played a significant role in economic development in China. Therefore, the study is expected to find a solution to the problems of the free economic zones in Incheon and provide directions for future development.

Application of Differential Evolution to Dynamic Economic Dispatch Problem with Transmission Losses under Various Bidding Strategies in Electricity Markets

  • Rampriya, B.;Mahadevan, K.;Kannan, S.
    • Journal of Electrical Engineering and Technology
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    • 제7권5호
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    • pp.681-688
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    • 2012
  • This paper presents the application of Differential Evolution (DE) algorithm to obtain a solution for Bid Based Dynamic Economic Dispatch (BBDED) problem including the transmission losses and to maximize the social profit in a deregulated power system. The IEEE-30 bus test system with six generators, two customers and two trading periods are considered under various bidding strategies in a day-ahead electricity market. By matching the bids received from supplying and distributing entities, the Independent System Operator (ISO) maximize the social profit, (with the choices available). The simulation results of DE are compared with the results of Particle swarm optimization (PSO). The results demonstrate the potential of DE algorithm and show its effectiveness to solve BBDED.

Multi Case Non-Convex Economic Dispatch Problem Solving by Implementation of Multi-Operator Imperialist Competitive Algorithm

  • Eghbalpour, Hamid;Nabatirad, Mohammadreza
    • Journal of Electrical Engineering and Technology
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    • 제12권4호
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    • pp.1417-1426
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    • 2017
  • Power system analysis, Non-Convex Economic Dispatch (NED) is considered as an open and demanding optimization problem. Despite the fact that realistic ED problems have non-convex cost functions with equality and inequality constraints, conventional search methods have not been able to effectively find the global answers. Considering the great potential of meta-heuristic optimization techniques, many researchers have started applying these techniques in order to solve NED problems. In this paper, a new and efficient approach is proposed based on imperialist competitive algorithm (ICA). The proposed algorithm which is named multi-operator ICA (MuICA) merges three operators with the original ICA in order to simultaneously avoid the premature convergence and achieve the global optimum answer. In this study, the proposed algorithm has been applied to different test systems and the results have been compared with other optimization methods, tending to study the performance of the MuICA. Simulation results are the confirmation of superior performance of MuICA in solving NED problems.

지역과 수도권 쇼핑몰 간 경쟁분석을 통한 지역격차 연구 (A System Dynamics Approach to Assessing Regional Disparity from Competitions of Online Shopping Malls)

  • 연승준;김상욱;황주성
    • 한국시스템다이내믹스연구
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    • 제2권1호
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    • pp.5-28
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    • 2001
  • The advent of Electronic Commerce is raising two hypothetical questions conflicting each other in economic point of view. The one is that cyberspace will eventually resolve the problem of economic disparity by presenting equal opportunities to local companies through the removal of barriers in terms of time and space. The other is that the problem of economic disparity will be amplified by the vicious cycle of reproduction on an enlarged scale residing in the new rules of digital economy. As an initial attempt to tackle the questions listed above, by introducing systems thinking and adopting the systems dynamics simulation technique this paper puts an effort to find some tentative answers to the questions possibly raised about the impact of electronic commerce on local economy on which little research has been conducted so far. The general scheme for the dynamism of systems where two groups of electronic malls compete each other and the findings presented in the paper would perhaps provide some ideas and directions for further study.

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OVERALL BENEFIT-DURATION OPTIMIZATION (OBDO) FOR OWNERS IN LARGE-SCALE CONSTRUCTION PROJECTS

  • Seng-Kiong Ting;Heng Pan
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.780-785
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    • 2005
  • This paper aims to consider an overall benefit-duration optimization (OBDO) problem for the sake of maximizing owner's economic benefits, whilst considering influences of schedule compression incurred opportunity income on the profitability of a large-scale construction project. Unlike previous schedule optimization models and techniques that have focused on project duration or cost minimization, with greater weight on contractors' interests, OBDO facilitates owner's economic benefits through overall benefit-duration optimization. In this paper, the objective function of OBDO model is formulated. An example is illustrated to prove the feasibility and practicability of the overall benefit-duration optimization problem. The significance of employing OBDO model and future research work are also described.

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발전정지와 교환방법을 적용한 실시간급전문제 최적화 알고리즘 (Optimization Algorithm for Real-time Load Dispatch Problem Using Shut-off and Swap Method)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제17권4호
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    • pp.219-224
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    • 2017
  • 경제급전 최적화 문제를 해결하는 결정론적인 알고리즘에 존재하지 않아 지금까지는 비결정론적인 휴리스틱 알고리즘들이 제안되고 있다. 이와 더불어 실시간 급전문제에 대한 연구는 거의 없는 실정이다. 본 논문은 발전정지 개념을 도입하여 실시간 급전의 최적화 문제를 풀 수 있는 알고리즘을 제안하였다. 제안된 알고리즘은 단위 발전량당 최대 비용이 소요되는 발전기는 발전을 중지시키는 기준을 적용하였다. 본 논문에서 제안한 발전정지 기준은 발전비용함수에서 밸브효과에 따른 비선형 절대치 함수를 제외한 2차 함수만을 대상으로 하였다. 경제급전 문제의 시험사례로 빈번히 활용되고 있는 데이터에 대해 제안된 알고리즘을 적용한 결과 기존 알고리즘들의 해를 크게 감소시킬 수 있었다.

건강보험의 지속을 위한 개혁과제 (Health Care Reform for Sustainability of Health Insurance)

  • 이규식
    • 한국병원경영학회지
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    • 제15권4호
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    • pp.1-26
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    • 2010
  • We achieved both industrialization and democratization during the shortest period in the world. We also achieved good performance in national health insurance: universal coverage, solidarity in financing, equitable access of health care. However, national health insurance system has faced the problem of sustainability: various expenditure and financing problems. The problem of sustainablity has two facets of economic sustainability and fiscal sustainability. Economic sustainability refers to growth in health spending as a proportion of gross domestic product(GDP). Rapid increasing rate of health spending exceeds the growth rate of domestic product. Growth in health spending is more likely to threaten other areas of economic activity. Concern on fiscal sustainability relates to revenue and expenditure on health care. Health care financing face demographic and technical obstacles. Democratic obstacle is aging problem. Technical obstacle is collection of contribution. Expenditure of health care has various problems in benefit structure and efficiency of health care system. In this article, I suggest several policy reforms to enhance sustainability: generating additional revenue from value added tax, changing method of levying contribution, increasing efficiency of health care system by introducing the competition principle. restructuring of benefit scheme of health insurance. contracting with health care institutions to provide health care services.

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고속의 유효전력 최적조류계산 알고리즘 (A Fast Optimization Algorithm for Optimal Real Power Flow)

  • 송경빈;김홍래
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.926-928
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    • 1998
  • A fast optimization algorithm has been evolved from a simple two stage optimal power flow(OPF) algorithm for constrained power economic dispatch. In the proposed algorithm, we consider various constraints such as power balance, generation capacity, transmission line capacity, transmission losses, security equality, and security inequality constraints. The proposed algorithm consists of four stages. At the first stage, we solve the aggregated problem that is the crude classical economic dispatch problem without considering transmission losses. An initial solution is obtained by the aggregation concept in which the solution satisfies the power balance equations and generation capacity constraints. Then, after load flow analysis, the transmission losses of an initial generation setting are matched by the slack bus generator that produces power with the cheapest cost. At the second stage we consider transmission losses. Formulation of the second stage becomes classical economic dispatch problem involving the transmission losses, which are distributed to all generators. Once a feasible solution is obtained from the second stage, transmission capacity and other violations are checked and corrected locally and quickly at the third stage. The fourth stage fine tunes the solution of the third stage to reach a real minimum. The proposed approach speeds up the coupled LP based OPF method to an average gain of 53.13 for IEEE 30, 57, and 118 bus systems and EPRI Scenario systems A through D testings.

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