• 제목/요약/키워드: population problem

검색결과 1,338건 처리시간 0.027초

최적의 TSP문제 해결을 위한 유전자 알고리즘의 새로운 집단 초기화 및 순차변환 기법 (New Population initialization and sequential transformation methods of Genetic Algorithms for solving optimal TSP problem)

  • 강래구;임희경;정채영
    • 한국정보통신학회논문지
    • /
    • 제10권3호
    • /
    • pp.622-627
    • /
    • 2006
  • TSP(Traveling Salesman Problem)는 N개의 도시가 주어질 때 어떠한 임의의 도시에서 출발하여 모든 도시를 단 한번만 방문하여 다시 출발지로 되돌아오는 여려 경로들 중 가장 짧은 거 리를 구하는 문제이다. 방문 도시수가 증가함에 따라 계산량이 기하급수적으로 증가하게 되는 문제로 인해 NP-Hard문제로 분류되며 유전자 알고리즘이 대표적으로 이용된다. TSP문제에 있어서 보다 우수한 결과를 얻기 위해 현재까지 다양한 연산자들이 개발되고 연구되어 왔다. 본 논문에서는 새로운 집단 초기화 방법과 순차변환 방법을 제안하여 기존의 방법들과 비교를 통해 성능 향상을 입증하였다.

GA-Hard 문제를 풀기 위한 공진화 모델 (Co-Evolutionary Model for Solving the GA-Hard Problems)

  • 이동욱;심귀보
    • 한국지능시스템학회논문지
    • /
    • 제15권3호
    • /
    • pp.375-381
    • /
    • 2005
  • 일반적으로 유전자 알고리즘은 최적 시스템을 디자인하는데 주로 이용된다. 하지만 알고리즘의 성능은 적합도 함수나 시스템 환경에 의해 결정된다. 두 개의 개체군이 꾸준히 상호작용하고 공진화 하는 공진화 알고리즘은 이러한 문제를 극복할 수 있을 것으로 기대된다. 본 논문에서는 GA가 풀기 어려운 GA-hard problem을 풀기 위하여 저자가 제안한 3가지 공진화 모델을 설명한다. 첫 번째 모델은 찾고자하는 해와 환경을 각각 경쟁하는 개체군으로 구성해 진화하는 방법으로 사용자의 환경설정에 의해 지역적 해를 찾는 것을 방지하는 경쟁적 공진화 알고리즘이다. 두 번째 모델은 호스트 개체군과 기생(스키마) 개체군으로 구성된 스키마 공진화 알고리즘이다. 이 알고리즘에서 스키마 개체군은 호스트 개체군에 좋은 스키마를 공급한다. 세 번째 알고리즘은 두 개체군이 서로 게임을 통해 진화하도록 하는 게임이론에 기반한 공진화 알고리즘이다. 각 알고리즘은 비주얼 서보잉, 로봇 주행, 다목적 최적화 문제에 적용하여 그 유효성을 입증한다.

인구분산 및 이동의 특성과 전망 (Characteristics of and Prospect for Population Distribution in Korea)

  • 최진호
    • 한국인구학
    • /
    • 제9권1호
    • /
    • pp.32-40
    • /
    • 1986
  • The purpose of the paper is to examine the nature of population distribution during the past 25 years; to evaluate effect of population redistribution policies which have been adopted by the government; and to suggest desirable future policy directions. The distinctive features of population distribution during the period of 196O~85 can be summarized as progress of rapid urbanization, decrease of absolute number of rural population and heavy concentration of population in the Seoul metropolitan area which have resulted in population maldistribution among regions. The problem of population concentration in the selected one or two large urban centers was first recognized by the government as early as in 1964. Since then numerous policy measures have been adopted to reduce the population concentration into the Seoul metropolitan area and thus to guide a sound population redistribution among regions. The overall assessment of various policies on population redistribution, however, revealed that the effect of the policy efforts has not been great as they originally anticipated. Various reasons can be cited for the failure of the past policies. Among them the followings were frequently mentioned; lack of integration among policy measures; weak linkage between relocation and accommodation; and non-existence of single authority for overall implementation of the polices. Based on the past experiences the followings are suggested in pursuing future policies. First, the short-term objective or target should be clearly defined. Second, policy measures have to be designed to go with rather than against market forces. Third, indirect incentives or aids are more effective than direct controls or regulations. Fourth, local participation has to be secured in every phase of policy formulation and implementation.

  • PDF

데모그라피의 역사적 배경과 한국인구의 지역적 편향분포의 지니 계수적 해석

  • 구자흥;이성철
    • 한국수학사학회지
    • /
    • 제16권2호
    • /
    • pp.103-116
    • /
    • 2003
  • Now we have faced to two fundamental population problems: The one is over-population problem in proportion to the nation's total area, 99,434 $km^2$, and the other is unbalanced population distributions in the provincial districts of administration (16th local governments). For example, the population density of Seoul city is 16,335 persons, and the nations population density of South Korea is 464 persons for 1 km$^2$. At the first part of this study, we introduced the origins and historical back grounds of Formal Demorgraphy. And the second part, we suggest some useful indicators of urbanization of rural populations in terms of Gini's Coefficients of Concentration. As the result, we can show that the ecological Gini's Coefficients of Concentration, during the periods covered by this study, have been increasing extraordinary: 0.349, 0.433, 0.532, 0.581, 0.633 and 0.626 in 1970, 1980, 1985, 1990, 1995, 2000 A.D. respectively. However, the trend of urbanization (concentration of population) of Korean population has been the relative equilibrium state of 0.63 from 1995 to 2000 A.D.

  • PDF

The Problem of Disjunctive Causal Factors: In Defense of the Theory of Probabilistic Causation

  • Kim, Joon-Sung
    • 논리연구
    • /
    • 제5권2호
    • /
    • pp.115-131
    • /
    • 2002
  • The problem of disjunctive causal factors is generalized as follows. Suppose that there are no factors of the kind considered so far that need to be held fixed in background contexts. Nevertheless, it is still possible that within the background contexts, each disjunct of a disjunctive causal factor X v W confers a different probability on an effect factor in Question. So a problem arises of how we identify a single causally significant probability of the effect factor in the presence of the disjunctive causal factor, assuming that each disjunct of the disjunctive causal factor confers a different probability on the effect factor. In this paper, I first introduce an experiment in which disjunctive causal factors seem to pose a problem for the theory of probabilistic causation. Second, I show how Eells' solution to the problem of disjunctive causal factors meets the problem that arises in the experiment. Third, I examine Hitchcock's arguments against Eells' solution, arguing that Hitchcock misconstrues Eells' solution, and disregards the feature of the theory of probabilistic causation such that a factor is a causal factor for another factor relative to a population P of a population type Q.

  • PDF

MODELING OF HUMAN INDUCED CO2 EMISSION BY ASSIMILATING GIS AND SOC10-ECONIMICAL DATA TO SYSTEM DYNAMICS MODEL FOR OECD AND NON-OECD COUNTRIES

  • Goto, Shintaro
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.3-8
    • /
    • 1998
  • Using GIS and socio-economical data the relationship between human activities and global environmental change Is Analysed from the view point of food productivity and CO2 emission. Under the assumption that the population problem, the food problem and global warming due to energy consumption can be stabilized through managing land use, impacts of human activities such as consumption of food, energy and timber on global environment changes, and global population capacity are Analysed using developed system dynamics model in the research. In the model the world is divided into two groups: OECD countries and the others. Used global land use data set Is land cover map derived from satellite data, and potential distribution of arable land is estimated by the method of Clamor and Solomon which takes into consideration spatial distribution of climate data such as precipitation and evapotranspiration. In addition, impacts of CO2 emission from human activities on food production through global warming are included in the model as a feedback. The results of the analysis for BaU scenario and Toronto Conference scenario are similar to the results of existing models. From the result of this study, the human habitability in 2020 is 8 billion people, and CO2 emission in 2020 based on BaU Scenario and on Toronto Scenario is 1.7 and 1.2 times more than the 1986's respectively. Improving spatial resolution of the model by using global data to distribute the environmental variables and sauce-economical indices is left for further studies.

  • PDF

중국 노인주거단지에 관한 실태조사분석 연구 - 북경시 동방태양성 주거단지를 중심으로 - (A Study on Analysis With Present Conditions of Elderly Community in China - Focused on Oriental Sun City in Beijing -)

  • 유양;이동숙;윤충열
    • 한국농촌건축학회논문집
    • /
    • 제19권4호
    • /
    • pp.33-40
    • /
    • 2017
  • Following the development of economy and progress of the society, the problem of aging population appears. In 1999, China had been classified as "aging society" and aging of population has become a serious social issue that affects the economic growth and social stability. And one of the crux issue is the dwelling of aged people. As a cosmopolitan city, Beijing keeps leading position on residential development. But facing grim problem of ageing population, and the problem of the elderly living has not been solved yet. At the beginning of 21 Century, the first aged community(Oriental Sun City) was built in Beijing, and attracted a large number of old people to move in. But there are many problems in the process of design and construction since there is not much correlative researches for planning and design of aged communities. With a view to aged communities in Beijing, this thesis intends to research on the planning and design of aged communities. This thesis will give reference to help the programming and design of aged communities.

뉴스초점 - 해파리의 이상증식과 피해현황 (Unusual population explosion af the jellyfish and damage status)

  • 강영승
    • 기술사
    • /
    • 제43권1호
    • /
    • pp.46-49
    • /
    • 2010
  • Sea temperature rise by global warming, depletion of fishery resources and ocean pollution have caused unusual population explosion of the jellyfish, The blooming of jellyfish have brought social problem and economic damage, Therefore the interdisciplinary study of jellyfish by scientists and countermeasure are needed.

  • PDF

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

  • Kim, Keewhan
    • Communications for Statistical Applications and Methods
    • /
    • 제22권1호
    • /
    • pp.15-18
    • /
    • 2015
  • Reunification, (considered a 'bonanza'), is often expected to bring economic and social benefits as well as solutions to the population aging problem; consequently, the study on the population structure of North Korea is salient. This paper reviews and talks on the North Korean population and implications. In view of reliability and consistency, the North Korean population appears at an explicit change compared to the past, and shows significant differences from the South, implying that it needs significant resources to integrate during reunification. Therefore, it is opportune to discuss the North Korean population prior to the clamor for the reunification.