• 한국주거학회논문집
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• 제16권1호
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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.

• Journal of Ecology and Environment
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• 제48권1호
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• pp.49-59
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• 2024

Background: The present study aims to identify the pattern and size of Juniperus species (Juniperus phoenicea and J. procera) in the natural forests in terms of tree dimension, size structure and density, discussing the existing both species in Sarrawat Mountains for suggesting the preservation, conservation, and sustainable development. For achieving this, the height and mean crown diameter of each individual was measured based on 2-4 diameter measurements per ind. (506 ind. for J. phoenicea and 322 ind. for J. procera). Results: The size index of both species was classified into 7 classes: the first (< 100 cm) and the second (100-200 cm) classes were chosen to represent the juvenile stage. The total mean of the J. phoenicea population increased with the increase of altitude, while the whole population decreased after altitude of 2,000 m. The total mean of the J. procera population increased with the increase of altitude till altitude of 2,000-2,100 m. Conclusions: The present study indicated that both of species grow at low altitudes, they only grow at altitude above 1,700 m above sea level. The present study indicated that the study area has the two Juniperus spp. (J. phoenicea and J. procera) associated together all over the area. The results were discussed and compared with other related studies.

• Animal Systematics, Evolution and Diversity
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• 제29권1호
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• pp.18-22
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• 2013

A recent study on the mitochondrial genetic variation of the Carassius auratus population in South Korea suggested that there are 3 distinct mitochondrial lineages in the country, and that they are geographically separated between westward rivers and southward rivers, respectively. In this study, the population genetic structure of amplified fragment length polymorphism (AFLP) of Carassius auratus was investigated. The results of analysis of molecular variance (AMOVA) supported the geographic distinction between westward and southward river populations, but only 3.66% of total genetic variance lies among these populations. The panmicticity of the AFLP genetic variation is backed up by the results of the neighbor-joining dendrogram drawn from a linearized pairwise $F_{ST}$ matrix and Bayesian clustering analysis. The discordance of genetic structure between mitochondrial and AFLP genetic variation may come from difference in effective population size between these markers and/or gene flow between westward and southward river populations through river capture events.

• 농업과학연구
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• 제42권4호
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• pp.397-406
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• 2015

Quantitative traits are mostly controlled by a large number of genes. Some of these genes tend to have a large effect on quantitative traits in cattle and are known as major genes primarily located at quantitative trait loci (QTL). The genetic merit of animals can be estimated by genomic selection, which uses genome-wide SNP panels and statistical methods that capture the effects of large numbers of SNPs simultaneously. In practice, the accuracy of genomic predictions will depend on the size and structure of reference and training population, the effective population size, the density of marker and the genetic architecture of the traits such as number of loci affecting the traits and distribution of their effects. In this review, we focus on the structure of Hanwoo reference and training population in terms of accuracy of genomic prediction and we then discuss of genetic architecture of intramuscular fat(IMF) and marbling score(MS) to estimate genomic breeding value in real small size of reference population.

• Asian-Australasian Journal of Animal Sciences
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• 제26권12호
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• pp.1672-1679
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• 2013

Linkage disequilibrium between markers or genetic variants underlying interesting traits affects many genomic methodologies. In many genomic methodologies, the effective population size ($N_e$) is important to assess the genetic diversity of animal populations. In this study, dairy cattle were genotyped using the Illumina BoviveHD Genotyping BeadChips for over 777,000 SNPs located across all autosomes, mitochondria and sex chromosomes, and 70,000 autosomal SNPs were selected randomly for the final analysis. We characterized more accurate linkage disequilibrium in a sample of 96 dairy cattle producing milk in Korea. Estimated linkage disequilibrium was relatively high between closely linked markers (>0.6 at 10 kb) and decreased with increasing distance. Using formulae that related the expected linkage disequilibrium to $N_e$, and assuming a constant actual population size, $N_e$ was estimated to be approximately 122 in this population. Historical $N_e$, calculated assuming linear population growth, was suggestive of a rapid increase $N_e$ over the past 10 generations, and increased slowly thereafter. Additionally, we corrected the genomic relationship structure per chromosome in calculating $r^2$ and estimated $N_e$. The observed $N_e$ based on $r^2$ corrected by genomics relationship structure can be rationalized using current knowledge of the history of the dairy cattle breeds producing milk in Korea.

• Journal of applied mathematics & informatics
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• 제30권1_2호
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• pp.183-200
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• 2012

A two-strain epidemic model with an age structure mutation and varying population is studied. By means of the spectrum theory of bounded linear operator in functional analysis, the reproductive numbers according to the strains, which associates with the growth rate ${\lambda}^*$ of total population size are obtained. The asymptotic stability of the steady states are obtained under some sufficient conditions.

• 한국경제지리학회지
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• 제11권4호
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• pp.549-563
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• 2008

도시의 성장이 경제발전에 긍정적인 영향을 가져온다는 점에도 불구하고 아직까지 우리나라에서는 도시의 구조를 파악하기 위한 연구가 상당히 미흡한 실정이다. 본고에서는 도시 간 규모의 분포구조와 도시 내 인구밀도함수 등을 통한 내적구조를 새로이 정의한 광역도시통계권을 기준으로 살펴보았다. 먼저, 도시순위규모법칙의 계수분석을 통한 한국의 광역도시통계권 간 인구분포구조를 비교하였다. 한국은 서울광역도시통계권의 규모가 상대적으로 매우 크며 행정구역 상의 인구규모 분포보다 실질적으로 훨씬 집중되어 있다. 이는 서울광역도시통계권이 상대적으로 지나치게 거대하든가 혹은 부산이나 대구, 대전 광역도시통계권의 성장이 상대적으로 뒤떨어진 것으로 해석된다. 한편 지리정보프로그램(Arc GIS)을 이용하여 도시 내의 중심상업지역에서부터의 거리에 따른 인구밀도함수나 부동산가격 등을 통하여 도시의 내적구조를 분석하였다. 표준도시모델(Standard Urban Model)에 따르면 일반적으로 도심에서 외곽으로 갈수록 인구밀도와 부동산 가격이 하락하는 형태를 보이지만 서울광역도시통계권의 외곽에서는 상대적으로 다른 광역도시통계권과는 달리 그 하향곡선이 무척 완만하였고, 이는 결국 도심확산(Urban Sprawl)이 활발히 일어나고 있음을 의미한다. 한편, 울산, 광주권, 그리고 수원-화성-오산권에서 인구분포와 고용분포 간의 공간적 불일치 정도가 큰 편이고 대전권과 인천권에서 작은 편으로 나타났다. 이러한 도시의 구조에 대한 분석은 지역정책의 운용에 있어서 많은 시사점을 줄 수 있다.

• 한국패류학회지
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• 제24권2호
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• pp.81-87
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• 2008

Distribution, population structure, and growth of the bivalve Protothaca euglypta were investigated for clams collected from the northwestern part of the East Sea of Russia. This species is distributed in further northern area than it was found earlier. In the southern area, this clam is found in the intertidal zone, up to 8 m in depth. It is one of the most numerous infaunal species of bivalves, and protected to wave action in the gravel-pebble and sand with rubble biotope. Population density of P. euglypta reaches 500 $spc./m^2$, and biomass 2 $kg/m^2$. Size and age composition of the local settlements and allometric growth of P. euglypta depend on a biotope. The growth rate of P. euglypta considerably reduces in case of the northern boundary area, whereas life span increases.

• Journal of Animal Science and Technology
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• 제62권4호
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• pp.438-448
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• 2020

This study was performed to increase the accuracy of genomic estimated breeding value (GEBV) predictions for domestic pigs using single-breed and admixed reference populations (single-breed of Berkshire pigs [BS] with cross breed of Korean native pigs and Landrace pigs [CB]). The principal component analysis (PCA), linkage disequilibrium (LD), and genome-wide association study (GWAS) were performed to analyze the population structure prior to genomic prediction. Reference and test population data sets were randomly sampled 10 times each and precision accuracy was analyzed according to the size of the reference population (100, 200, 300, or 400 animals). For the BS population, prediction accuracy was higher for all economically important traits with larger reference population size. Prediction accuracy was ranged from -0.05 to 0.003, for all traits except carcass weight (CWT), when CB was used as the reference population and BS as the test. The accuracy of CB for backfat thickness (BF) and shear force (SF) using admixed population as reference increased with reference population size, while the results for CWT and muscle pH at 24 hours after slaughter (pH) were equivocal with respect to the relationship between accuracy and reference population size, although overall accuracy was similar to that using the BS as the reference.

• Journal of Ecology and Environment
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• 제42권3호
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• pp.111-119
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• 2018

Background: Juniperus chinensis L. populations are distributed locally on several areas including coastal cliffs which are difficult to access in the central eastern Korea. Wild populations inhabit relatively barren environments such as rocky areas and cliffs, which are very sensitive to even minor environmental disturbances including artificial interventions and natural disturbances, and thus demonstrate great fluctuations in the population size and density. This study aims to analyze the genetic diversity, differentiation, and genetic structure of each population in order to provide useful data required to establish a substantial conservation strategy of J. chinensis. Results: The genetic diversity of J. chinensis at the population level (P = 78.7%, h = 0.282, S.I. = 0.420) was somewhat higher compared with those measured in the same genus, Juniperus. The genetic differentiation degree among nine populations established naturally in central eastern Korea was 11.50% and that among sub-populations within the same area was 5.52%. On the other hand, genetic variation of individuals within the populations was 82.93%. But frequency of the main allele was different among loci. In particular, fixation of allele frequency and occurrence of rare allele in the highly isolated population suggest a likelihood that genetic drift would occur in populations of this plant. As the result of analysis on the genetic structure of nine populations, nearby populations and isolated populations tended to form separate clusters from each other as the hypothetical number of clusters (K) increase. Conclusions: This result implies that if the population size of J. chinensis is reduced due to environmental change and artificial and/or natural disturbances in the future, it could affect negatively on the genetic diversity of the plant species. In order to maintain and conserve genetic diversity of J. chinensis, ecological network, which can help genetic exchange among the local populations, should be prepared, and conservation strategies in situ as well as ex situ are also required with continuous monitoring.