• Korea journal of population studies
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• v.30 no.3
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• pp.1-31
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• 2007

Korea, China and Japan have been undergoing economic development, demographic transition and population aging, in a speed unparalleled in world history. This paper examines, for each of these countries, on (i) the trend and prospect of the effective dependency burden (EDB) in terms of stable population and (ii) the optimum fertility path which will lead to a stable population with the minimum level of EDB under the trend and prospect of decreasing age specific mortality rates. It then evaluates (iii) the transitory EDB costs of pro-natal policies during the adjustment process of stabilization and (iv) the effectiveness of other supplementary policies which influence EDB parameters.

• Korea journal of population studies
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• v.4 no.1
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• pp.5-13
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• 1981

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.259-273
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• 2021

We conducted a study to investigate the characteristics of the carbon cycle of two streams (located in Shig a Prefecture, Japan), having similar size, namely, the Adokawa stream (length: 52 km, area: 305 km², watershed population: 8,000) and the Yasukawa stream (length: 62 km, area: 380 km², watershed population: 120,000), but with different degree of human activity. Samples were collected from these two streams at 14 (Adokawa stream) and 23 (Yasukawa stream) stations in the flowing direction. The dissolved inorganic carbon (DIC) concentration and the stable carbon isotope ratio of DIC (δ¹³C-DIC) were measured in addition to the watershed features and the chemical variables of the stream water. The δ¹³C-DIC (-9.50 ± 2.54‰), DIC concentration (249 ± 76 µM), and electric conductivity (52 ± 13 µS/cm) in Adokawa stream showed small variations from upstream to downstream. However, the δ¹³C-DIC (-8.68 ± 2.3‰) upstream of Yasukawa stream was similar to that of Adokawa stream and decreased downstream (-12.13 ± 0.43‰). DIC concentration (upstream: 272 ± 89 µM, downstream: 690 ± 37 µM) and electric conductivity (upstream: 69 ± 17 µS/cm, downstream: 193 ± 37 µS/cm) were higher downstream than upstream of Yasukawa stream. The DIC concentration of Yasukawa stream was significantly correlated with watershed environmental variables, such as, watershed population density (r = 0.8581, p<0.0001, n = 23), and forest area percentage of the watershed (r = -0.9188, p<0.0001, n = 23). δ¹³C-DIC showed significant negative correlation with the DIC concentration (r = -0.7734, p<0.0001, n = 23), electric conductivity (r = -0.5396, p = 0.0079, n = 23), and watershed population density (r = -0.6836, p = 0.0003, n = 23). Our approach using a stable carbon isotope ratio suggests that DIC concentration and δ¹³C-DIC could be used as indicators for monitoring the health of stream ecosystems with different watershed characteristics.

• Environmental Mutagens and Carcinogens
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• v.18 no.2
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• pp.109-115
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• 1998

Fluorscence in situ hybridization with chromosome-specific probe has been shown to be a valid and rapid method for detection of chromosome rearrangements induced by chemical and physical agents. This method is useful for quantifying structural aberrations, expecially for stable ones, such as translocation and insertion, which are difficult to detect with conventional method in human lymphocyte. In order to use the FISH method as a biodosimeter for monitoring human population exposed to various chemical and physical agent, baseline level of chromosome rearragement was established. Blood from forty four healthy adults were collected and analysed with whole chromosome-specific probes by human chromosome 1,2 and 4. The frequencies of stable translocation were 2.45 per 100 cell equivalent and those of insertion, color juction, acentric and dicentric were 0.32, 3.28, 0.23 and 0.27 per 100 cell equivalent respectively. The frequencies of chromosome rearragements increased with age in both sexes except for dicenrics. From above result, stable aberrations accumulate with age and it may reflect integrated lifetime exposure of adverse environment.

• Animal cells and systems
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• v.8
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• pp.71-71
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• 2004

• Journal of the Korea Convergence Society
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• v.10 no.7
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• pp.243-249
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• 2019

This study is aimed at offering a typology of changes in the social participation of middle-aged and older population and explore determinants for each type of such changes. The data employed for analysis are the 1st survey (2006) through the 6th version (2016) of the Korea Aging Research Panel Survey. Among the respondents of the panel survey, 1,327 males and 1,520 females with a total of 2,847 respondents were analyzed. As a result of applying the growth mixture modelling through the SPS 22.0 and M-plus 8.0 statistical programs, the changes in the social participation of middle-aged and older population have been classified into the 'high-decreasing', 'moderate-increasing' and 'low-stable' trajectory classes. Analysis of the determinants for each class shows that higher the education level, the more likely they are to belong to the high-decreasing and moderate-increasing classes than the low-stable class, and the more the population lives in urban areas, the more likely they are to belong to high-decreasing trajectory class than to low-stable class. Also, it was found that the probability of belonging to moderate-increasing trajectory class was higher than that of the low-stable class when there was no occupation. Through the results of these analyses, the implications of promoting social participation of middle-aged and older population were discussed.

• Journal of Environmental Impact Assessment
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• v.18 no.5
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• pp.293-299
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• 2009

Wintering migratory species of white-fronted geese (Anser albifrons) are common visitor in South Korea, and this study examined the survivorship of white-fronted geese in the Junam Reservoir with the application of Population Viability Analysis (PVA) technique. In Junam PVA analysis was done for the next 50 years using factors of breeding population, sex ratios, survivorship in the VORTEX program. As a result white-fronted geese will reach to carrying capacity within 40 years, and population will reach to carrying capacity later when it becomes smaller. Also with a large initial population white-fronted geese will reach to carrying capacity earlier. In conclusion, for the next 50 years the white-fronted geese are expected to a long-term survival with stable condition with survivorship (0.03) and extinction rate (0.0).

• Korea journal of population studies
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• v.8 no.1
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• pp.20-46
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• 1985

The increase of the population has an effect on the increase of students. The high birthrate, which means the extension of enrollments in the future, requires preparation of enough facilities and equipment for education. However, the educational conditions of Korea are not yet developed, and in such a situation the increase of enrollments makes the improvement of educational conditions difficult. Besides, the influx of students into the large cities has made complex educational problems such as a decrease of students in the rural area and a change for the worse of the educational conditions in the urban area. For the development of education in such a situation, an emphasis should be put not only on security of a stable educational finance but also on activation of family planning project and curb of population influx into large cities in the realm of population policy. In addition, population education for the youth should be strengthened in order that they can have sound view of family life, married life, children, and sex moral. For the way the young married live has relationship with the number and quality of children in the future of our nation.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.2
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• pp.120-128
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• 2021

The objective of this study was to analyze the genotype of black-spotted pond frog (Pelophylax nigromaculatus) using seven microsatellite loci to quantify its genetic diversity and population structure throughout the spatial scale of basins of Han, Geum, Yeongsan, and Nakdong Rivers in South Korea. Genetic diversities in these four areas were compared using diversity index and inbreeding coefficient obtained from the number and frequency of alleles as well as heterozygosity. Additionally, the population structure was confirmed with population differentiation, Nei's genetic distance, multivariate analysis, and Bayesian clustering analysis. Interestingly, a negative genetic diversity pattern was observed in the Han River basin, indicating possible recent habitat disturbances or population declines. In contrast, a positive genetic diversity pattern was found for the population in the Nakdong River basin that had remained the most stable. Results of population structure suggested that populations of black-spotted pond frogs distributed in these four river basins were genetically independent. In particular, the population of the Nakdong River basin had the greatest genetic distance, indicating that it might have originated from an independent population. These results support the use of genetics in addition to designations strictly based on geographic stream areas to define the spatial scale of populations for management and conservation practices.

• Safety and Health at Work
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• v.10 no.3
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• pp.384-388
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• 2019

The horse stable hand workers are one of the most important occupations in horse-racing industry. However, suicide problem of the horse stable hand workers in Korea has raised the necessity of new study on how these workers experience mental health problems such as occupational stress and depression in organizational situation. Therefore, this study investigated the occupational stress and depression level of the horse stable hand workers and identified the structural relationship in the horse-racing industry through a detailed interview. A total of 207 horse stable hand workers participated in this study, and occupational stress and depression level were surveyed using the Korean Occupational Stress Scale (KOSS) and Korean version of the Center for Epidemiologic Studies-Depression Scale (CES-D). The results of this study showed that the occupational stress level of horse stable hand workers was higher than the median of Korean population. The significant difference in occupational stress among the detail job grade was also identified. In addition, 34% of the horse stable hand workers showed high risk of depression, and job demand, organizational system, and inappropriate compensation as the subfactors of occupational stress were showed to mainly affect depression. Although there are some limitations according to the field survey, this study also has significant meaning in that it identifies the relationship between the occupational characteristics of the horse stable hand workers and the mental health. It will be necessary to study the diverse organizational situation and individual mental health for new occupations.