• Title/Summary/Keyword: population distribution

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A Hybrid Estimation of Distribution Algorithm with Differential Evolution based on Self-adaptive Strategy

  • Fan, Debin;Lee, Jaewan
    • Journal of Internet Computing and Services
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    • v.22 no.1
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    • pp.1-11
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    • 2021
  • Estimation of distribution algorithm (EDA) is a popular stochastic metaheuristic algorithm. EDA has been widely utilized in various optimization problems. However, it has been shown that the diversity of the population gradually decreases during the iterations, which makes EDA easily lead to premature convergence. This article introduces a hybrid estimation of distribution algorithm (EDA) with differential evolution (DE) based on self-adaptive strategy, namely HEDADE-SA. Firstly, an alternative probability model is used in sampling to improve population diversity. Secondly, the proposed algorithm is combined with DE, and a self-adaptive strategy is adopted to improve the convergence speed of the algorithm. Finally, twenty-five benchmark problems are conducted to verify the performance of HEDADE-SA. Experimental results indicate that HEDADE-SA is a feasible and effective algorithm.

Analysis on Change of Population Structure and Locational Characteristics of Children's Parks : Focusing on Children's Parks in Cheongju (인구구조 변화와 어린이 공원의 입지특성 분석 연구)

  • Shin, ByungChuel;Lee, Eun-Yeob
    • Land and Housing Review
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    • v.9 no.3
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    • pp.29-36
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    • 2018
  • This study aims at suggesting directions to make children's parks considering the actual groups using them by comparative analysis of age distribution in residents within area of use and locations of children's parks with regards to changes in population structure of low birth rate and aging. Cheongju was selected for the study, and the current status of children's parks and population structure were categorized into six stages and the investigation and analysis were conducted by statistics by population group and by using Arc GIS Program. As a result of the analysis, children under 13 were 13.1% of the entire population in Cheongju and share of middle-aged and aged group including middle-aged was 31.3%. Park area per one children under 13 was 5.9㎡ and based on walking use area(250m), average number of parks available by autonomous district was eight. As a result of the analysis of characteristics of distribution of children's parks, they are densely located in old downtowns or the distribution density was relatively high in newly developed areas such as Osong-eup or Ochang-eup. However, outer rural areas have no children's parks or relatively low rate. As a result of the analysis on population structure and co-efficient of park location, in nine autonomous districts, aged group is increasing, leading to decrease use of children's parks. If resident rate aged group is higher in the region where a children's park is located, it is necessary to re-compose the existing one to different one or to change purposes of parks to be planned. Also, in the area with similar rates in both children's group and aged group, composing complex parks for both of them could be considered. This study has limitations by not conducting field studies about the current status of use of children's parks in areas where the population structure has been changing and not suggesting specifically new types of parks according to changes in population structure. It is necessary to conduct the following studies about relationship between children's parks and policies for composing parks responding to changes in population structure in neighboring regions in future.

Growth and Spatial Distribution Characteristics of Rhus javanica Populations Sowed on Cut-Slopes - Focusing on the Dae-Ji Mountain Case Study - (비탈면에 파종된 붉나무(Rhus javanica) 개체군의 생육 및 공간분포 특성 - 용인 대지산 사례지역을 중심으로 -)

  • Lim, Chae-young;Oh, Choong-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.6
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    • pp.39-49
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    • 2015
  • This study was to evaluate the growth and spatial distribution characteristics of Rhus javanica population. The study was conducted between 2015 January and July at the cut-slope revegetation site in Dae-Ji Mountain. Seeds of native species were sowed on the disturbed cut-slope in 2002. There were 119 vascular plant species 55 families and 94 genera on the cut-slope. Compositae, Rosaceae, and Leguminosae plants were dominant species, which are pioneer species in dry and barren site. Canopy of trees covered 44.1% total area, which was 8.3% increase from 2008. Rhus javanica, main species, dominated all DBH classes except DBH >24cm. Albizzia julibrissin showed high frequency in the 6~17cm DBH class and Salix koreensis was abundant at >12cm. Elaeagnus umbellata, Corylus heterophylla var. heterophylla, Alnus sibirica, and Acer pictum were not observed. Rhus javanica population was the most frequently observed on the south facing cut-slope. The average DBH of Rhus javanica was $7.3({\pm}3.7)cm$ and the average height of them was $5.2({\pm}1.7)m$. Annual average DBH growth was 7.9mm/yr and the maximum growth(12.0mm/yr) was the $3^{rd}$ year. It decreased after $6^{th}$ years. Although Rhus javanica population in the Dae-Ji Mountain was a seed originated plantation, the forest had reverse J shape diameter frequency distribution. It indicated that the forest is uneven-aged forest. The Rhus javanica population was expected to sustain.

The Characteristics of Population and Family Composition by the Unit Type in Apartment Houses (아파트단지의 단위세대별 인구 및 가족형구성에 관한 분석)

  • Chung Sa-Hee;Choi Seung Hee
    • Journal of the Korean housing association
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    • v.16 no.1
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    • pp.97-104
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    • 2005
  • The purpose of this study is to understand changes of the population and family composition in apartment houses. The main contents of this study is to find the way of housing planning through the analysis of the population and family composition by the unit types. The population and family composition were studied by computer data base program to 11,000 residents of selection 4 apartments houses. The structure of the family types proved to be constant by the result of analyzing the 10 family types. If the family types of certain resident's groups are given, this study will be able to estimate population structure to them. The transition of the population and the family composition changes to the unit types proved to be constant by the time. The distribution of manhood and matured children is tend to change according to how large the size of house is, and to change the structure of family composition.

A Study on the Analysis of Population Dynamics and the Model of population Relocation (人口過程의 分析과 人口配置計劃의 모델模索)

  • 박찬계;함종욱
    • Journal of the Korean Statistical Society
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    • v.10
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    • pp.145-157
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    • 1981
  • Regional relocation of population in Korea is required strongly from natural and environmental sides for substantial growth of economy and the rigorous revival national economy against especially internationalization. This paper aimed for analysed the population distribution by regional and special characteristics of the inter-migration and showed the direction of population policy through the model building. Relocation methods of population by region has been examined through the process from the approach method by Haurin's production function to the approach by the utility function. The examination of the development model is done efficiently, how utility these approach models are depends on that scientific and composite plan for population problems against forced policy should be taken precedence.

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Genetic Variability and Geographical Distribution of Mycotoxigenic Fusarium verticillioides Strains Isolated from Maize Fields in Texas

  • Ortiz, Carlos S.;Richards, Casey;Terry, Ashlee;Parra, Joselyn;Shim, Won-Bo
    • The Plant Pathology Journal
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    • v.31 no.3
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    • pp.203-211
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    • 2015
  • Maize is the dominant cereal crop produced in the US. One of the main fungal pathogens of maize is Fusarium verticillioides, the causative agent of ear and stalk rots. Significantly, the fungus produces a group of mycotoxins - fumonisins - on infested kernels, which have been linked to various illnesses in humans and animals. Nonetheless, durable resistance against F. verticillioides in maize is not currently available. In Texas, over 2.1 million acres of maize are vulnerable to fumonisin contamination, but understanding of the distribution of toxigenic F. verticillioides in maize-producing areas is currently lacking. Our goal was to investigate the genetic variability of F. verticillioides in Texas with an emphasis on fumonisin trait and geographical distribution. A total of 164 F. verticillioides cultures were isolated from 65 maize-producing counties. DNA from each isolate was extracted and analyzed by PCR for the presence of FUM1- a key fumonisin biosynthesis gene - and mating type genes. Results showed that all isolates are in fact F. verticillioides capable of producing fumonisins with a 1:1 mating-type gene ratio in the population. To further study the genetic diversity of the population, isolates were analyzed using RAPD fingerprinting. Polymorphic markers were identified and the analysis showed no clear correlation between the RAPD profile of the isolates and their corresponding geographical origin. Our data suggest the toxigenic F. verticillioides population in Texas is widely distributed wherever maize is grown. We also hypothesize that the population is fluid, with active movement and genetic recombination occurring in the field.

Measuring Inequalities in Terms of the Distribution of Urban Population (도시화의 특징과 불평등도 분석)

  • 박주문
    • Korea journal of population studies
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    • v.18 no.2
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    • pp.98-114
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    • 1995
  • Since 1962 the Korean society has undergone a rapid transformation under government policies to achieve maximum economic growth. Urbanization via massive rural to urban migration has been observed to be connected with a rapid economic development. Based on the data from the government publications such as Population and Housing Census Reports and Korean Urban Yearbooks, this study measures inequalities in terms of the distribution of urban population. In a historical context, the pace of urbanization during the period 1966-1970 was characterized as the most rapid and the urban-rural growth difference(URGD), which is a valuable measure of the pace of urbanization, was the highest. In terms of regional pattern, Seoul dominated the urbanization picture of Korea during the period 1966-1970. Its annual growth rate was the fastest among those shown during the period 1960 to 1990 and also highest. However, Seoul's primacy was pulled down since 1970. The Gini coefficient, which is the most common general measure of inequalities in distribution, was the highest in 1980. Since 1980 it has continued to fall. As a result, it was lower in 1990 than in 1970. Despite lowering Gini coefficient, inequalities are still large. A concentration index also showed the same trends as those of Gini coefficent.

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Ploidy Characteristics of NS-1 Cells Resistant to BCNU or CCNU and Immune mediated Cytotoxicity in vitro (항암제와 세포독성에 내성을 나타내는 생쥐 임파종 세포(NS-1)의 염색체 분포특성)

  • Shim, Woo-Nam;Kim, Young-Min;Kim, Joo-Deuk;Lee, Won-Young
    • The Journal of the Korean Society for Microbiology
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    • v.19 no.1
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    • pp.85-108
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    • 1984
  • In order to study the relationship between resistance of tumor cells to anticancer drugs and immunologic cytotoxicity and their chromosome number, a line of cancer cells (NS-1) was exposed to BCNU and CCNU in vitro. Characteristics of the distribution of chromosome number of the survived cells were then comparatively analyzed. Effect of immune mediated cytotoxicity, i.e. complement and cell-mediated cytotoxicity, on the ploidy characteristics was observed in the same way. NS-1 cells were found to be a population of neoplastic cells of heterogeneity having 5 to 115 chromosomes per cell in metaphase. The majority of the cells were belong to the class of chromosome number 56 to 60 which were considered as the stem cell line. Dramatic changes in the distribution of chromosome number following drug treatment were not observed. However the range of chromosome distribution was slightly changed. Characteristics of chromosomal distribution of drug treated cells were not significantly varied by different doses of drug treated. Changed chromosomal distribution patterns of drug treated cells were reversible, especially the cells having 56 to 60 chromosomes recovered rapidly. Cells having 41-60 and 61-80 chromosomes among cells treated with BCNU and cells with 41-60 chromosomes after CCNU treatment were the major population which regenerated continuously. Following BCNU treatment cells having 61-80 chromosomes were not varied much whereas CCNU treatment affects the population in the same class. Chromosomal aberrations were significantly enhanced by BCNU and CCNU treatment. The frequency of chromosomal aberrations was greater in cells having more than 40 chromosomes compared with that in cells having less than 40 chromosomes. Changes in ploidy characteristics of the cells following complement mediated and cell mediated cytotoxicity were not significant. Therefore it was tentatively concluded that association of numerical distribution pattern of NS-1 cells with the response to the treatment used in this experiment was not recognized.

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Confidence Intervals for a Proportion in Finite Population Sampling

  • Lee, Seung-Chun
    • Communications for Statistical Applications and Methods
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    • v.16 no.3
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    • pp.501-509
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    • 2009
  • Recently the interval estimation of binomial proportions is revisited in various literatures. This is mainly due to the erratic behavior of the coverage probability of the well-known Wald confidence interval. Various alternatives have been proposed. Among them, the Agresti-Coull confidence interval, the Wilson confidence interval and the Bayes confidence interval resulting from the noninformative Jefferys prior were recommended by Brown et al. (2001). However, unlike the binomial distribution case, little is known about the properties of the confidence intervals in finite population sampling. In this note, the property of confidence intervals is investigated in anile population sampling.

Distribution characteristics of heterotropic bacteria population in slow sand filters (완속여과 여층 내 종속영양세균의 분포 특성)

  • Park, Jong-Geun;Kim, Seong-Su
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.1
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    • pp.23-30
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    • 2009
  • Slow sand filtration (SSF) was the first engineered/mechanical filtration process used in drinking water treatment. In SSF, untreated water slowly percolate through a bed of porous sand. Biological activity within the sand bed have the strongest influence on removal efficiency of pollutants by slow sand filtration. In this study, the microbial population distributions in slow sand filters operated at the various operation conditions was evaluated. The concentrations of $10^4$ to $10^5$ CFU per g dry wt. were observed. No significant differences were seen between the number of filter-covered materials. The data indicate that the temperature has affect on population distribution. Also, the light exposure was influenced on microorganism in slow sand filtration according to the heterotropic plate counts. The role of microorganism within the sand media requires further study.