• Title/Summary/Keyword: Economic problem

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Economic Design of Local Area Networks using Genetic Algorithms (유전자 알고리즘을 이용한 경제적 LAN 설계)

  • Yum Chang-Sun;Lee Han-Jin
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.28 no.2
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    • pp.101-108
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    • 2005
  • In this paper, the design problem of local area networks is defined as finding the network topology minimizing cost subject to reliability constraint. The design problem includes issues such as multiple choices of link type for each possible link, multiple choices of hub type for each hub, and allocation of the users to the hubs. To efficiently solve the problem, a genetic approach is suggested. According to the experiments, the proposed approach improves search performance.

Determination of an Economic Lot Size of Color Filters in TFT-LCD Manufacturing (TFT-LCD 공정에서의 Color Filter 의 경제적 Lot Size 의 결정)

  • Jeong, Bong-Ju;Sohn, So-Young
    • IE interfaces
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    • v.10 no.1
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    • pp.47-55
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    • 1997
  • This paper deals with an assembly process of the TFT glasses and the color filters in LCD manufacturing. Two specific problems are presented and solved. One is a matching problem to find the best matches between a set of TFT glasses and a set of color filters, which result in the maximum number of good LCD assemblies. A simple mathematical model is constructed for this problem and an optimal solution can be obtained using an existing algorithm. The other is a main problem that requires a determination of an economic lot size of the color filters which are going to be assembled with a given set of TFT glasses. A Bayesian dynamic forecasting model is developed to predict the defective patterns of color filters. Based on the predicted defective rate of color filters, the minimum lot size of the color filters can be determined to minimize the probability of losing good TFT glasses and color filters.

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A Study on The Application of Hopfield Neural Network to Economic Load Dispatch (홉필드 신경회로망의 경제 급전에의 적용에 관한 연구)

  • Park, Young-Moon;Bang, Hoon-Jin;Lee, S.C.
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.832-834
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    • 1996
  • This paper presents the research on the application of the Hopfield Neural Network to the Economic Load Dispatch problem. The ELD problem has convex cost functions as the objective functions, power balance equation and real power lower/upper limits as the constraints. So we have shown that the possibility of the application of the Hopfield Neural Network to the ELD problem. Through the case study, the simulation results are very close to the numerical method and the dynamic programming method.

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Economic Load Dispatch Using Modified Lagrangian ANN (Modified Lagrangian 신경망을 이용한 경제 급전)

  • Kim, Y.H.;Lee, S.C.
    • Proceedings of the KIEE Conference
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    • 1996.11a
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    • pp.133-136
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    • 1996
  • In the paper, an artificial neural network (ANN) approach based on Lagrange multiplier method (Lagrangian ANN) is used to solve an economic load dispatch (ELD) problem. Traditionally ELD problem has one convex cost function as its objective function and nonlinear constraints such as power balance and maximum-minimum limits of real power. In this study, modification is given to the Lagrangian ANN proposed by Gong et all[5] to guarantee the convergence to the optimal solution. Simulation results demonstrate the effectiveness of the proposed method applied to the ELD problem.

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An Improved Particle Swarm Optimization for Economic Dispatch Problems with Prohibited Operating Zones (경제급전 문제에의 개선된 PSO 알고리즘 적용)

  • Jeong, Yun-Won;Lee, Woo-Nam;Kim, Hyun-Houng;Park, Jong-Bae;Shin, Joong-Rin
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.850-851
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    • 2007
  • This paper presents an efficient approach for solving the economic dispatch (ED) problems with prohibited operating zones using an improved particle swarm optimization (PSO). Although the PSO-based approaches have several advantages suitable to the heavily constrained nonconvex optimization problems, they still have the drawbacks such as local optimal trapping due to the premature convergence (i.e., exploration problem) and insufficient capability to find nearly-by extreme points (i.e., exploitation problem). This paper proposes an improved PSO framework adopting a crossover operation scheme to increase both exploration and exploitation capability of the PSO. The proposed method is applied to ED problem with prohibited operating zones. Also, the results are compared with those of the state-of-the-art methods.

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A Study on the Problematic Issues and Residents Preference of Administrative Boundary Integration for Rurban Development : A Case Study on the WanJu County (도시주변 행정구역통합대상 농촌지역의 쟁점과 주민의사에 관한 연구)

  • Chung, Cheol-Mo
    • Journal of Korean Society of Rural Planning
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    • v.5 no.2 s.10
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    • pp.14-23
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    • 1999
  • This studys concerns with a critical issues of urban and rural integration for rurban development. Todays, many of urban-rural integrated cities are confronted with the negative effects of administrative boundary integration. The first problem is induced from the developmental gaps and different residential demands between the core-city and peripheral-county. The second problem is social-economic and administrative unification costs neglected. The third problem is the environmental pollutions and degradations in peripheral-county by rapid urbanization. The forth problem is the inequality of the public services and regional investments in the urban-rural Integrated cities. The fifth problem is the administrative relation and financial distribution between core-city and residual province when the urban-rural integrated core-city becomes large urban city. The results of the questionnaire analysis as follows. The first point, the preference of administrative boundary integration is different in intra-areas of urban-rural integrated county by it's location. The second point, the diversity of preference of residents depends on theirs job, age, resdential period, education and income level. So, administrative boundary integration must consider the many important factors which affect the socio-economic situations between the core-city and peripheral-county. In conclusion, residents' preference for the admistrative boundary integration depends on their situation without rational approach for macro regional development. In this contexts, comprehensive approach for the urban-rural administrative boundary integration is needed in consistent with rapid change of local government's functions.

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Private Education Expenditure for Children and Economic Well-being of Household (가계의 사교육비 지출과 경제적 복지)

  • 이승신
    • Journal of the Korean Home Economics Association
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    • v.40 no.7
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    • pp.211-227
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    • 2002
  • The issue of children′s education is the most important issue for all households in Korea. It is certain that the issue of private education for children is the first issue among household′s issues. This study is to recognize the current pictures of household primate education of Korean households. Also, whether the expenditure of private education effect the economic will-being of household. The data for this study was"the 3th Korean Labor Panal", conducted by Lobor in Korea. The sample was 1950 households from the panel data. The results of this study was as following: 1. The mean of monthly private education expenditure was 149273won for all households and 217,100won for households with high school students. 2. Almost 70% households had economic burden for private education expenditure. 0% households had no economic burden. 3. The factors of influencing the level of economic burden for private education were mother′s education level, mother′s job, the number of children, living location, monthly income, total asset of household′s. The factors of influencing the amount of monthly private education expenditure positively were living in 4. The economic well-being of household was analyzed by socio-economic variables, household′s financial variables, monthly private education expenditure, the level of economic burden of private education. The economic well-being were sub-categorized 4 divisions; the level of economic problem, the level of satisfaction for household′s income, the level of satisfaction for general living, the level of subject economic condition)

Trends Analysis of Suicidal Poisoning in Korea- Comparison before and after the IMF Crisis and the Economic Recession (IMF와 경기침체 전후 음독자살 환자에 대한 분석 -1997년부터 2004년까지 일개 대학병원 응급센터 연구조사를 중심으로-)

  • Lee Won Jae;Park Kyu Nam;Choi Seung Pil;Lee Mi Jin
    • Journal of The Korean Society of Clinical Toxicology
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    • v.3 no.1
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    • pp.33-39
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    • 2005
  • Purpose: Nowadays the Korean society is in the center of time of the social change. Because of dissociation of traditional family, IMF (International Monetary Fund) crisis and economic recession, the mortality rate of suicidal attempts are increasing annually. The majority of suicidal attempts were by poisoning considering the characteristics of korean society. Therefore we studied to find out the characteristics of suicidal poisoning before and after social economic stress, and to suggest the direction for the proper management. Methods: We reviewed medical records of 547 patients of suicide by poisoning who visited the emergency medical centers of St. Mary's hospitals from 1997 to 2004. For the annual trends analysis, we analyzed the demographic and toxicologic data of these patients compared with before and after IMF crisis (1998) and the economic recession ($2003\~2004$). Results: At the time of IMF and the economic recession, the number of suicidal poisoning increased, especially in fifth decade. The refusal rate of toxicological emergency treatment increased. Also the mortality rate and the admission rate to ICU (Intensive Care Unit) increased during the same period. In the result of the comparison analysis, clinical severity and mortality of social problem group were higher. However they couldn't be treated appropriately because of financial problem and the family indifference. Conclusion: At the economic recession period, the severity of suicidal poisoned patients was high. But the refusal rate of toxicologic treatment also increased, so the patients had lost the chance for proper toxicologic treatment. Therefore they would be supported by medical institution and public health.

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Optimization of Economic Load Dispatch Problem Using Linearly Approximated Smooth Fuel Cost Function (선형 근사 평활 발전 비용함수를 이용한 경제급전 문제의 최적화)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.191-198
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    • 2014
  • This paper proposes a simple linear function approximation method to solve an economic load dispatch problem with complex non-smooth generating cost function. This algorithm approximates a non-smooth power cost function to a linear approximate function and subsequently shuts down a generator with the highest operating cost and reduces the power of generator with more generating cost in order to balance the generating power and demands. When applied to the most prevalent benchmark economic load dispatch cases, the proposed algorithm is found to dramatically reduce the power cost than does heuristic algorithm. Moreover, it has successfully obtained results similar to those obtained through a quadratic approximate function method.

A Research on Economic Evaluation of Public Web Service (공공 웹 서비스의 경제성 평가에 관한 연구)

  • 박정선
    • The Journal of Society for e-Business Studies
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    • v.6 no.2
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    • pp.57-71
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    • 2001
  • This paper provides an economic evaluation model for public web services which are mainly operated by government agencies. Though there are various services, this paper focus on services for bottleneck problem solving and management information providing. This paper suggests quantitative and qualitative effects of public web services and evaluates them with I-NET users using e-mail surveys. This Paper mv provide a guideline for the future investment on public web services.

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