• Title/Summary/Keyword: Migration Scheme

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Below Replacement-level Fertility in Korea: A Myth or a Reality\ulcorner (한국의 대체출산이하 인구)

  • Lee, Hung-Tak
    • Korea journal of population studies
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    • v.11 no.1
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    • pp.146-158
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    • 1988
  • In order to examine differential mortality, the life tables for the insured persons in national pension scheme were estimated by sex and types of coverage(the insured in workplaces vs. the insured in rural areas). The averages of 1994-1996 data are used for insured in workplaces, but 1996 data are used for insured in rural areas. Life expectancies at the age of 18 are 59.5 years and 67.2 years each for insured males and females and thus 7.7 years longer for females than males in workplaces. Sex difference in mortality reduces as age increases, and more rapidly at younger ages than old ages. For insured in rural areas, life expectancies at the age of 18 are 51.4 years and 61.1 years each for insured males and females and thus sex difference is 9.7 years. The greater sex difference in mortality in rural areas can be explained by sex selective migration. The difference of life expectancy between insured in workplaces and insured in rural areas is 8.1 years for males, and 6.1 years for females. Because rural-urban difference in educational attainment is greater for males than females, the greater difference in life expectancy is observed for males than females.

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Key Methodologies to Effective Site-specific Accessment in Contaminated Soils : A Review (오염토양의 효과적 현장조사에 대한 주요 방법론의 검토)

  • Chung, Doug-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.32 no.4
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    • pp.383-397
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    • 1999
  • For sites to be investigated, the results of such an investigation can be used in determining foals for cleanup, quantifying risks, determining acceptable and unacceptable risk, and developing cleanup plans t hat do not cause unnecessary delays in the redevelopment and reuse of the property. To do this, it is essential that an appropriately detailed study of the site be performed to identify the cause, nature, and extent of contamination and the possible threats to the environment or to any people living or working nearby through the analysis of samples of soil and soil gas, groundwater, surface water, and sediment. The migration pathways of contaminants also are examined during this phase. Key aspects of cost-effective site assessment to help standardize and accelerate the evaluation of contaminated soils at sites are to provide a simple step-by-step methodology for environmental science/engineering professionals to calculate risk-based, site-specific soil levels for contaminants in soil. Its use may significantly reduce the time it takes to complete soil investigations and cleanup actions at some sites, as well as improve the consistency of these actions across the nation. To achieve the effective site assessment, it requires the criteria for choosing the type of standard and setting the magnitude of the standard come from different sources, depending on many factors including the nature of the contamination. A general scheme for site-specific assessment consists of sequential Phase I, II, and III, which is defined by workplan and soil screening levels. Phase I are conducted to identify and confirm a site's recognized environmental conditions resulting from past actions. If a Phase 1 identifies potential hazardous substances, a Phase II is usually conducted to confirm the absence, or presence and extent, of contamination. Phase II involve the collection and analysis of samples. And Phase III is to remediate the contaminated soils determined by Phase I and Phase II. However, important factors in determining whether a assessment standard is site-specific and suitable are (1) the spatial extent of the sampling and the size of the sample area; (2) the number of samples taken: (3) the strategy of taking samples: and (4) the way the data are analyzed. Although selected methods are recommended, application of quantitative methods is directed by users having prior training or experience for the dynamic site investigation process.

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