• 한국인구학
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• 제9권1호
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• pp.54-68
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• 1986

This study was designed to make a comparative analysis of fertility control policies in developing countries selected from Asia and Latin America. Considering the size and the density of population, the history of the fertility control policy, and the availability of references, eight countries were chosen among Asian developing countries that have adopted the fertility control as an official policy. All of nine countries in Latin America that have adopted family planning as an official policy were included in this study. An attempt was made to formulate an analytical framework to be used for a comparative analysis of fertility control policies. It can be represented by a continuum which consists of individual approaches and structural approaches to fertility control at both extremes. It represents fairly well the controversies between those who advocate family planning and those who advocate measures beyond family planning, but assumes that the two sides of the controversy form a continuum of approaches to fertility control. Various fertility control policies of each country were placed along this continuum and analyzed. The results of the analysis can be summarized as follows: (a) Those countries that have higher population pressure in terms of either the size of population or the population density tend to adopt fertility control policies earlier in time. (b) Those countries that have higher population pressure in terms of either the size of population or the population density tend to adopt more comprehensive measures along the continuum of fertility control policies. (c) Those countries that adopted more comprehensive measures along the continuum seem to have succeeded in reducing their level of fertility more effectively. (d) Developing countries in Asia tend to adopt more comprehensive measures to control fertility than those in Latin American countries. (e) The reduction of fertility in developing countries seems to be associated with both the fertility control policies and the level of socioeconomic development.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1843-1851
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• 2018

Objective: We aimed to characterize linkage disequilibrium (LD) and effective population size ($N_e$) in a Korean Yorkshire population using genomic data from thousands of individuals. Methods: We genotyped 2,470 Yorkshire individuals from four major Grand-Grand-Parent farms in Korea using the Illumina PorcineSNP60 version2 BeadChip, which covers >61,565 single nucleotide polymorphisms (SNPs) located across all chromosomes and mitochondria. We estimated the expected LD and inferred current $N_e$ as well as ancestral $N_e$. Results: We identified 61,565 SNP from autosomes, mitochondria, and sex chromosomes and characterized the LD of the Yorkshire population, which was relatively high between closely linked markers (>0.55 at 50 kb) and declined with increasing genetic distance. The current $N_e$ of this Korean Yorkshire population was 122.87 (106.90; 138.84), while the historical $N_e$ of Yorkshire pigs suggests that the ancestor $N_e$ has decreased by 99.6% over the last 10,000 generations. Conclusion: To maintain genetic diversity of a domesticated animal population, we must carefully consider appropriate breed management methods to avoid inbreeding. Although attenuated selection can affect short-term genetic gain, it is essential for maintaining the long-term genetic variability of the Korean Yorkshire population. Continuous and long-term monitoring would also be needed to maintain the pig population to avoid an unintended reduction of $N_e$. The best way to preserve a sustainable population is to maintain a sufficient $N_e$.

• Journal of Ecology and Environment
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• 제43권3호
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• pp.320-331
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• 2019

Background: Dioecious plant species having both male and female plants have been investigated regarding sex-related characteristics such as sex ratio, sex-differential resource requirements, and spatial segregation of the sexes. Habitat loss and fragmentation are major threats to the survival of plant populations, but dioecious species are particularly more prone to such habitat degradation than non-dioecious species because of their dimorphic sexual system. We examined the sex-related demographics of two Ilex cornuta populations being different regarding land use history. Methods: During 2016-2017, we examined I. cornuta trees with a basal diameter ${\geq}1.5cm$ in the Yongsu-ri population (YS population) and the Gotjawal Provincial Park population (GP population). Plant sex (male, female, or unsexed) was identified. The tree size (basal diameter and height of the main stem), clonal production (the ramet numbers per genet), and vitality for each clone were measured. The associations between population, sex, tree size, clonal production, and vitality were examined using ANOVAs and contingency table analyses. Finally, point pattern analyses using O-ring statistics were conducted to assess spatial patterns. Results: Upon excluding unsexed trees, the YS population with 74 trees was significantly male-biased (0.66), while the GP population with only 26 trees had a 1:1 sex ratio. In both populations, males and females did not differ in tree size. Although the mean number of ramets differed significantly between populations, females tended to produce more ramets than males. The proportion of weak trees was significantly higher in the YS than in the GP population. Neither population showed evidence of spatial segregation of the sexes. Conclusions: The two populations of dioecious I. cornuta are characterized by the small number of trees and relatively high frequencies of non-reproductive trees. Both indicate that these populations are quite susceptible to environmental and genetic stochasticity. On the other hand, the differences between populations in sex ratio, clonal production, and vitality suggest that conservation efforts for I. cornuta need to be population-specific. In order to help recover and enable this vulnerable species to persist, it is necessary to find ways to enhance their sexual reproduction and simultaneously reduce habitat disturbances due to anthropogenic activities.

• 응용통계연구
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• 제27권4호
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• pp.513-521
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• 2014

일반적으로 현 시점에서 목표로 하고 있는 추정량의 산포가 지난시점의 추정량의 산포보다 크다면 지난시점과 비교하여 현 시점의 표본의 크기는 줄어드는 것이 타당하다. 계속조사에서 지난 시점의 추정량의 변동계수와 모집단의 크기 변동과 현 시점의 추정량의 목표오차를 이용하여 표본의 크기를 결정하는 것을 연구한 여러 논문들이 있다. 그런데 모집단은 크기의 변동과 산포의 변동이 있을 수 있으므로 본 연구에서는 지난 시점의 추정량의 변동계수와 모집단의 크기, 모집단의 산포 변동과 현 시점의 추정량의 목표오차를 반영하여 현 시점의 표본의 크기를 구하는 문제를 연구한다. 또한 모의실험을 통하여 기존 표본크기의 공식들과 비교분석한다.

• 대한가정학회지
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• 제20권1호
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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.

• Animal Bioscience
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• 제36권5호
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• pp.692-703
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• 2023

Objective: The main goals of this investigation were to i) assess the population structure and genetic diversity and ii) determine the efficiency of the ongoing breeding program in a closed flock of Angora rabbits through pedigree analysis. Methods: The pedigree records of 6,145 animals, born between 1996 to 2020 at NTRS, ICAR-CSWRI, Garsa were analyzed using ENDOG version 4.8 software package. The genealogical information, genetic conservation index and parameters based on gene origin probabilities were estimated. Results: Analysis revealed that, 99.09% of the kits had both parents recorded in the whole dataset. The completeness levels for the whole pedigree were 99.12%, 97.12%, 90.66%, 82.49%, and 74.11% for the 1st, 2nd, 3rd, 4th, and 5th generations, respectively, reflecting well-maintained pedigree records. The maximum inbreeding, average inbreeding and relatedness were 36.96%, 8.07%, and 15.82%, respectively. The mean maximum, mean equivalent and mean completed generations were 10.28, 7.91, and 5.51 with 0.85%, 1.19%, and 1.85% increase in inbreeding, respectively. The effective population size estimated from maximum, equivalent and complete generations were 58.50, 27.05, and 42.08, respectively. Only 1.51% of total mating was highly inbred. The effective population size computed via the individual increase in inbreeding was 42.83. The effective numbers of founders (f_e), ancestors (f_a), founder genomes (f_g) and non-founder genomes (f_ng) were 18, 16, 6.22, and 9.50, respectively. The fe/fa ratio was 1.12, indicating occasional bottlenecks had occurred in the population. The six most influential ancestors explained 50% of genes contributed to the gene pool. The average generation interval was 1.51 years and was longer for the sire-offspring pathway. The population lost 8% genetic diversity over time, however, considerable genetic variability still existed in the closed Angora population. Conclusion: This study provides important and practical insights to manage and maintain the genetic variability within the individual flock and the entire population.

• 한국인구학
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• 제5권1호
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• pp.4-16
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• 1982

The Korean Population Control Program has been implementing under the jurisdiction of the Ministry of Health and Social Affairs through an existing network of health centers. This arrangement was successful in bringing population growth down to targeted level by the end of the Fourth Five Year Economic Planning, 1981. It is expected, however, that future goal will be harder to reach due to difficulty of reducing traditional family size norms further and to the projected increasing the number of eligible couples as the past Korean war baby boom generation enters the reproductive activity in the next few years. The recognition of the need for modification of population policy is increasing. The 1980 census shows that the total number of population reached approximately 38.5 million with 1.57 per cent of the growth rate. It was projected that the size of Korean Population will reach around 42 million and 51 million in 1986 and 2000 respectively. Furthermore, there is some argument as to whether decline in the birth rate in Korea is too slow to meet government target. Hence, a new development of population policy and greatly increased amount of effort will be needed in order to achieve Zero Population Growth Rate before the year 2050. The development of future national population policy and its related area are recommended as follow: 1. It is highly recommended that the population planning law governing both vital events of birth and death and population migration should be legislated. 2. The National Population Policy Council, Chaired by Deputy Prime Minister should be activated to implement and coordinate population program within ministries. 3. Responsible organization of population and family planning program should be established as a Bureau unit at central government level. 4. For the improvement of national vital registration, an existing system should be studied and developed.

• 한국산림과학회지
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• 제94권2호통권159호
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• pp.117-120
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• 2005

This study was conducted to estimate population size and investigate habitat characteristics for the conservation and management of Amur goral Nemorhaedus caudatus raddeanus in DMZ (Demilitarized Zone) of Gangwon Province in South Korea from November 2003 to May 2004. The Amur gorals counting were carried out by assistance of military soldiers who guards the southern boundary of DMZ. Four hundred sixty individuals were estimated as total population size in DMZ of Gangwon Province. Deciduous forest, rocky area and coniferous forest were dominant land cover types in habitat of Amur goral. DMZ and its vicinity of Gangwon Province are very important areas for the conservation of this species. It is needed to establish management plan for the conservation of Amur goral and their habitats in DMZ.

• 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.

• 한국경제지리학회지
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• 제13권3호
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• pp.487-497
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• 2010

본 연구의 목적은 도시의 소득 및 지출함수를 이용하여 우리나라 7대 광역시의 인구규모가 적정 수준에 있는 지를 분석하는 것이다. 효용극대화 가계와 이윤극대화 생산자 문제의 균형인구를 완전경쟁조건으로부터 도출한 결과, 최적인구 규모는 도시의 기술수준 및 공공서비스 수준에 의해 결정된다. 이러한 측면에서 각 도시의 인구규모 수준을 살펴보면 서울, 부산, 대구, 인천 등은 과밀한 것으로 광주, 대전, 울산 등은 과소한 것으로 나타났다.