• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.767-771
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• 2002

Breeding efficiencies were compared among three population schemes: a single population, a population with two subpopulations and a population with three sub-populations. A simulation experiment of selection was carried out for 10 generations with 20 replications each by comparing average breeding values and inbreeding coefficients among the three population schemes. Phenotypes of three traits were generated with a model comprising 36 loci, each with additive genetic effects and residuals distributed normally. Among the three population schemes, the single population scheme was definitely superior to the other two with regards to selection response and inbreeding. The multiple sub-population scheme was, however, considered to be an alternative population scheme when the difference in economic weights of the traits was small among the sub-populations, assuming moderate inbreeding depression for traits and crossbreeding. The scheme with two sub-populations had a higher genetic value than that with three subpopulations; however, the genetic values of the schemes were comparable when maternal heterosis was taken into account. The choice of population schemes may depend on the cost-sharing policy between the breeding population and the commercial population rather than just the breeding efficiency.

• Journal of Korean Society of Rural Planning
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• v.25 no.4
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• pp.99-107
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• 2019

This paper analyzed the characteristics of population change from 2000 to 2018 in 466 mountainous areas using resident registration data from the Ministry of the Interior and Safety, and projected the population in those areas through 2050 with the cohort change ratio method. The population had dramatically decreased from 2000 to 2009. With the slowing population decrease after 2010, the population has increased gradually since 2014. Especially the population of ages over 65 in 2018 had increased 34% compared to 2000, while the working age population had decreased 29%. This shows that population aging becomes serious problems in the mountainous area. Assuming the cohort change ratios from 2010 to 2015 and child-woman ratio in 2015 remain constant, it appeared that the projected population of the mountainous area dropped to 1.26 million in 2030 and 820,000 in 2050. It is expected to have a population with an inverted pyramid structure showing a gender imbalance with more females in 60's and 70's. Although it continues to show the recent population growth in mountainous area, population in mountainous area is expected to consistently decrease. Therefore, it is required to develop policies and strategies to promote an influx of people into mountainous area for maintaining functionality and sustainability of mountainous areas.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.1-19
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• 2000

This study is to investigate and analyze regional patterns of aging in Taejeon Metropolitan city-the overpopulated area of Choong-Cheong Province-by cohort analysis method. According to the population structure transition caused by rapid social and economic changes, Korea has made a rapid progress in population aging since 1970. This trend is so rapid that we should prepare for and cope with aging society. It is not only slow to cope with it in our society, but also there are few studies on population aging of the geographical field in Korea. The data of this study are the reports of Population and Housing Censuses in 1975 and 1985 and General Population and Housing Censuses with 10% sample survey in 1995 taken by National Statistical Office. The research method is to sample as the aging district the area with high aged population rate where the populations over 60 reside among total population during the years of 1975, 1985, 1995 and to sample the special districts of decreasing population where the population decreases very much and the special districts of increasing population in which the population increases greatly, presuming that the reason why aged population rate increases is that non-elderly population high in mobility moves out. It is then verified and ascertained whether it is true or not with cohort analysis method by age. Finally regional patterns in the city are found through the classification and modeling by type based on the aging district, the special districts of decreasing population, and the special districts of increasing population. The characteristics of the regional patterns show that there is social population transition and that non-elderly population moves out. The aging district with the high aged population rate is divided into high-level keeping-up type, relative falling type below the average of Taejeon city in aging progress, and relative rising type above the average of the city. This district can be found at both the central area of the city and the suburbs because Taejeon city has the characteristic of over-bounded city. But it cannot be found at the new built-up area with the in-migration of large population. The special districts of decreasing population where the population continues to decrease can be said to be the population doughnuts found at the CBD and its neighboring inner area. On the other hand, the special districts of increasing population where the population continues to increase are located at the new built-up area of the northern part in Taejeon city. The special districts of decreasing population are overlapping with the aging district and higher in aged population rate by the out-migration of non-elderly population. The special districts of increasing population are not overlapping with the aging district and lower in aged population rate by the in-migration of non-elderly population. To clarify the distribution map of the aging district, the special districts of decreasing and increasing population and the aging district are divided into four groups such as the special districts of decreasing population group-the same one as the aging district, the special districts of decreasing population group, the special districts of increasing population group, and the other district. With the cohort analysis method by age used to investigate the definite increase and decrease of aging population through population transition of each group, it is found that the progress of population aging is closely related to the social population fluctuation, especially that aged population rate is higher with the out-migration of non-elderly population. This is to explain each model of CBD, inner area, and the suburbs after modeling the aging district, the special districts of decreasing population, and the special districts of increasing population in Taejeon city. On the assumption that the city area is a concentric circle, it is possible to divide it into three areas such as CBD(A), the inner area(B), and the suburbs(C). The special districts of increasing and decreasing population in the city are divided into three districts-the special districts of decreasing population(a), the special districts of increasing population(b), and the others(c). The aging district of this city is divided into the aging district($\alpha$) and the others($\beta$). And then modeling these districts, it is probable to find regional patterns in the city. $Aa{\alpha}$ and $Ac{\beta}$ patterns are found in the CBD, in which $Aa{\alpha}$ is the special district of decreasing population and is higher in aged population rate because of aged population low in mobility staying behind and out-migration of non-elderly population. $Ba{\alpha}$, $Ba{\beta}$, $Bb{\beta}$, and $Bc{\beta}$ patterns are found in the inner area, in which neighboring area $Ba{\alpha}$ pattern is located. $Bb{\beta}$ pattern is located at the new developing area of newly built apartment complex. $Cb{\beta}$, $Cc{\alpha}$, and $Cc{\beta}$ patterns are found in the suburbs, among which $Cc{\alpha}$ pattern is highest in population aging. It is likely that the $Cc{\beta}$ under housing land readjustment on a large scale will be the $Cb{\beta}$ pattern. As analyzed above, marriage and out-migration of new family, non-elderly population, with house purchase are main factors in accelerating population aging in the central area of the city. Population aging is responsible for the great increase of aged population with longer life expectancy by the low death rate, the out-migration of non-elderly population, and the age group of new aged population in the suburbs. It is necessary to investigate and analyze the regional patterns of population aging at the time when population problems caused by aging as well as longer life expectancy are now on the increase. I hope that this will help the future study on population aging of the geographical field in Korea. As in the future population aging will be a major problem in our society, local autonomy should make a plan for the problem to the extent that population aging progresses by regional groups and inevitably prepare for it.

• Management Science and Financial Engineering
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• v.16 no.3
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• pp.49-70
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• 2010

Customer population management models can be classified into three categories: the first category includes the models that analyze the customer population at cohort level; the second one deals with the customer population at aggregate level; the third one has interest in the interactions among the customer populations in the competitive market. Our study proposes a model that can analyze the dynamics of customer population in consumer-durables market at aggregate level. The dynamics of customer population includes the retention curves from the purchase or at a specific duration time, the duration time expectancy at a specific duration time, and customer population growth or decline including net replacement rate, intrinsic rate of increase, and the generation time of customer population. For this study, we adopt mathematical ecology models, redefine them, and restructure interdisciplinary models to analyze the dynamics of customer population at aggregate level. We use the data of previous research on dynamic customer population management at cohort level to compare its results with those of ours and to demonstrate the useful analytical effects which the precious research cannot provide for marketers.

• Korea journal of population studies
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• v.5 no.1
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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.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.433-438
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• 2004

In this paper, we at first describe the linear age-dependent population system. In addition, we introduce the nonlinear population system. Using these age-dependent population systems, we evaluate the stability of these age-dependent population systems and determine the optimal birth rates that realize a target distribution which relaxes an aging population. In this paper, we focus on Japan's population and we use the amount of demographic statistics of Japan in year 2000.

• Journal of Applied Reliability
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• v.15 no.3
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• pp.192-196
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• 2015

It is important to obtain the information of population center for establishing the balanced development policy of a nation. In this note, the population center of Korea is obtained using 2010 Census data and compared with the past population centers. The weighted average method is used for calculating the population center. The results of this note will be able to contribute in the regional population distribution policies.

• Korea journal of population studies
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• v.9 no.1
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• pp.69-88
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• 1986

The purpose of the present study is to find out and analyze the degree of population concentration of 10 selected cities. The data used for the present study were derived from the Government publications including the population and Housing Census Reports from 1966 through 1980 and the Korea Urbanic Yearbooks from 1969 through 1981. The major findings of the study were summarized as follows: The data revealed that changes of population size were more rapidly proceeded in Seoul than any other city and regarding to population composition, these selected cities had more male population than female population. The proportion of the productive age group of these selected cities were found to be higher than that of whole country each year, especially the proportion 20∼24 aged group was higher in 1980 than any other year. The number of net migrants in these cities during last 20 years, 1960∼80 was 910, 656 as Seoul obtained the largest net migrants and among the selected cities, Seoul, Busan, Daegu, Incheon, Daejeon and Jeonju had a big change in volume of net migration population, especially in 30∼39 aged group in 1980. According to Gini Concentration Ratio and Index of Concentration, the population concentration was the highest in 1980 and the population concentration was intensively accelerated during 1966∼ 1970.

• Korea journal of population studies
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• v.9 no.1
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• pp.32-40
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• 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.

• Journal of Educational Research in Mathematics
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• v.24 no.3
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• pp.375-385
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• 2014

This study compares the confidence interval estimation of population mean with that of population ratio, and considers whether these two estimations ensures consistency. As a result, this study suggests the following acquisition method of consistency : dealing with population mean and population ratio in the same mode, substituting the observed or experimental value of sample standard deviation for standard deviation in population in setting a confidence interval of both population mean and population ratio, and distinguishing population ratio $\hat{P}$ from its observed vale $\hat{p}$.