• Title/Summary/Keyword: population problem

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A Cooperative Coevolutionary Algorithm for Optimizing a Reverse Logistics Network Model (역물류 네트워크 모델의 최적화를 위한 협력적 공진화 알고리즘)

  • Han, Yong-Ho
    • Korean Management Science Review
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    • v.27 no.3
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    • pp.15-31
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    • 2010
  • We consider a reverse logistics network design problem for recycling. The problem consists of three stages of transportation. In the first stage products are transported from retrieval centers to disassembly centers. In the second stage disassembled modules are transported from disassembly centers to processing centers. Finally, in the third stage modules are transported from either processing centers or a supplier to a manufacturer, a recycling site, or a disposal site. The objective is to design a network which minimizes the total transportation cost. We design a cooperative coevolutionary algorithm to solve the problem. First, the problem is decomposed into three subproblems each of which corresponds to a stage of transportation. For subproblems 1 and 2, a population of chromosomes is constructed. Each chromosome in the population is coded as a permutation of integers and an algorithm which decodes a chromosome is suggested. For subproblem 3, an heuristic algorithm is utilized. Then, a performance evaluation procedure is suggested which combines the chromosomes from each of two populations and the heuristic algorithm for subproblem 3. An experiment was carried out using test problems. The experiments showed that the cooperative coevolutionary algorithm generally tends to show better performances than the previous genetic algorithm as the problem size gets larger.

The application of a Genetic Algorithm with a Chromosome Limited Life for the Distribution System Loss Minimization Re-configuration Problem (배전손실 최소화문제에서 개체수명을 고려한 유전적 알고리즘의 적용)

  • Choi, Dai-Seub;Lee, Myung-Un;Cho, Taek-Koo;Kim, Jong-Yung;Song, Min-Jong
    • Proceedings of the KIEE Conference
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    • 2002.07a
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    • pp.320-326
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    • 2002
  • Distribution system loss minimization re-configuration is 0-1 planning problem, and the number of combinations requiring searches is extremely large when dealing with typical system scales. For this reason, the application of a genetic algorithm (GA) seems attactive to solve this problem. Although Genetic algorithms are a type of random number search method, they incorporate a multi-point search feature and are therefore superior to one-point search techniques. The efficiency of GAs for solving large combinational problem has received wide attention. Further, parallel searching can be performed and the optimal solution is more easily reached. In this paper, for improving GA convergence characteristics in the distribution system loss minimization re-configeration problem, a chromosome "Limited Life" concept is intro duced. Briefly, considering the population homogenization and genetic drift problems, natural selection is achieved by providing this new concept, in addition to natural selection by fitness. This is possible because individuals in a population have an age value. Simulations were carried out using a model system to check this method's validity.

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Optimum Population Projection in Korea: An Environmental Perspective (환경 측면에서 한국의 적정인구 추계)

  • Jeong, Dae-Yuon
    • Korea journal of population studies
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    • v.29 no.1
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    • pp.269-292
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    • 2006
  • The current environmental problem is global, and threatens the very existence of human beings. Many factors have been argued as the causes of environmental problem. The examples include anthroponcentric human perspective on nature, increase in the knowledge on nature, development of technology, economic growth and unequal distribution, and population increase, etc. The scholars who argues population increase have focused on over-population. However, the estimation of optimum population size has not been attempted in terms of environmental carrying capacity. In such a context, this paper aims at estimating optimum population size in South Korea in terms of environmental carrying capacity. The estimation was done from two approaches. One was based on the state of environment, the other was based on 'the desirable state of environment' Koreans expect. The former is termed an objective approach, while the latter is termed an approach based on social consensus. About 47.5 millions were estimated from the former approach, and 48.5 millions from the latter approach. However, optimum population size increase by 50.5 millions if government increase environmental budget to 2.00% among total budget. As such, different optimum population size is estimated according to the values of variables. The most significant variable determining optimum population size is environmental budget, and followed by supply of clean energy. The estimated optimum population size was based on the time-series data from 1993 to 2002. Therefore, time-series data collected from other years will result in different estimation model, and then different optimum population size will be estimated.

The re-projections under 7 age on Korean registered population and a comparison with the reported population statistical data (주민등록 0세-6세 인구의 역 추정과 기존 인구통계와의 출생아수 비교)

  • Kim, Jong-Tae
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.6
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    • pp.1145-1153
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    • 2009
  • The problem of Korean registered population is that population classified by age increases as one grows older until 6 age or 7 age. This paper is to suggest an algorithm of the re-projection under 7 age on Korean registered population and to analysis of comparison with the reported population statistical data. As the result, the reprojections population is trusted in the number of 0 age on the comparison of other reported population statistical data.

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A Study on the Contents of Population Education in Home Economics (가정학에서의 인구교육내용 연구 - 가족관계분야를 중심으로 -)

  • 김순옥
    • Journal of the Korean Home Economics Association
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    • v.20 no.1
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    • pp.87-96
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    • 1982
  • For the solution of population problem, a population education is urgently need since family member size(that is population size) will be on the decrease fro the reason of changes in family consciousness by population education. The population education should be carried out interdisciplinary, but, above all, home economics is more suitable to the population education. In this study, the issues are the contents of population education in relation to family relations of home economics. Those contents are as follows: 1. A change in family consciousness through the value of child 1) Conventional value of child 2) Criticism about conventional value of child 3) Current value of child 4) Desirable number of children 2. A change in family consciousness through the preparation for one's declining years 1) Analysis of periodic family life cycle by number of children 2) Desirable number of children 3. A change in family consciousness through the parental responsibility 1) Mental responsibility 2) Physical responsibility 3) Economics responsibility 4. A change in family consciousness through the relationship between parents and children 1) Conventional relationship 2) Current relationship 3) Desirable relationship 5. A change in family consciousness through the relationship between husband and wife 1) Conventional relationship 2) Current relationship 3) Effects of children on the relationship of husband and wife By the above contents of population education in the field of family relations of home economics parents will have their deliberate plans and aims.

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A Genetic Algorithm for the Ship Scheduling Problem (선박운항일정계획 문제의 유전해법)

  • 이희용;김시화
    • Journal of the Korean Institute of Navigation
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    • v.24 no.5
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    • pp.361-371
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    • 2000
  • This paper treats a genetic algorithm for ship scheduling problem in set packing formulation. We newly devised a partition based representation of solution and compose initial population using a domain knowledge of problem which results in saving calculation cost. We established replacement strategy which makes each individual not to degenerate during evolutionary process and applied adaptive mutate operator to improve feasibility of individual. If offspring is feasible then an improve operator is applied to increase objective value without loss of feasibility. A computational experiment was carried out with real data and showed a useful result for a large size real world problem.

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A Study on the Population Structure of Democratic People's Republic of Korea

  • Jeon, Saebom;Kim, Seong Eun;Park, Yousung
    • Communications for Statistical Applications and Methods
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    • v.22 no.1
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    • pp.1-10
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    • 2015
  • The re-unification of the two Koreas is seen as a potential solution to the aging problem and low fertility, along with the increase in the old population structure of the Republic of Korea. Population structure is an indicator of national competitiveness or growth, but little is known officially about the populations of Democratic People's Republic of Korea (DPRK). Understanding the population structure of the DPRK is important to prepare for re-unification and estimate the socio-economic costs of national welfare under a re-unified Korea. In this paper, we assess reliability of the two modern national censuses of DPRK and use the limited resources available to reconstruct the intercensal populations between these two censuses. Excess deaths from the 1995 famine are estimated at 489,972 to 574,306 and are close to the estimates of Goodkind et al. (2011) and the reconstructed populations in the of DPRK implies a big difference between two Koreas.

The implementation of the Multi-population Genetic Algorithm using Fuzzy Logic Controller

  • Chun, Hyang-Shin;Kwon, Key-Ho
    • Proceedings of the KAIS Fall Conference
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    • 2003.11a
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    • pp.80-83
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    • 2003
  • A Genetic algorithm is a searching algorithm that based on the law of the survival of the fittest. Multi-population Genetic Algorithms are a modified form of genetic algorithm. Therefore, experience with fuzzy logic and genetic algorithm has proven to be that a combination of them can efficiently make up for their own deficiency. The Multi-population Genetic Algorithms independently evolve subpopulations. In this paper, we suggest a new coding method that independently evolves subpopulations using the fuzzy logic controller. The fuzzy logic controller has applied two fuzzy logic controllers that are implemented to adaptively adjust the crossover rate and mutation rate during the optimization process. The migration scheme in the multi-population genetic algorithms using fuzzy logic controllers is tested for a function optimization problem, and compared with other group migration schemes, therefore the groups migration scheme is then performed. The results demonstrate that the migration scheme in the multi-population genetic algorithms using fuzzy logic controller has a much better performance.

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The Decision of Critical Population Size for Releasing Micro Data Files (마이크로데이터 제공에 따른 임계모집단 크기 결정)

  • NamKung, Pyong;So, Joung-Hyun
    • Communications for Statistical Applications and Methods
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    • v.17 no.6
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    • pp.791-801
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    • 2010
  • This study reviews the concept of disclosure, disclosure risks, and uniqueness. The number of uniqueness in the population is of great importance in evaluating the disclosure risk of micro data files. We approach this problem by considering some basic superpopulation models including the Multinomial-Dirichlet model, the Poisson- Gamma model of Bethlehem et al. (1990) and Takemura (1997), and the Modified Multinomial-Dirichlet model. We decided the critical population size of each superpopulation model for four different superpopulation models.

Problems of Employment of the Population and Directions of Their Regulation in the Conditions of War

  • Zakharchyn, Galyna;Antonov, Andriі;Voityk, Oleksandra;Plotka, Lyubov;Mirko, Nataliia
    • International Journal of Computer Science & Network Security
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    • v.22 no.11
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    • pp.303-307
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    • 2022
  • The purpose of the study is to determine the key aspects of the problems of employment of the population and the directions of their state regulation in war conditions. Employment policy involves a system of measures to create conditions for a more complete use of the potential of labor and business activity of the able-bodied population, linking this activity through taking into account the specifics of group interests with the tasks and guidelines for socio-economic development. But in the conditions of war, this problem acquires a new relevance. For the study, a number of theoretical methods of analysis were used. Based on the results of the study, the key aspects of the problems of employment of the population and the directions of their state regulation in war conditions were identified.