• Korea journal of population studies
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• v.28 no.1
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• pp.149-172
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• 2005

장래인구추계(population projection)는 한 사회의 인구수 및 구조 변화를 추정하는 것으로 사회의 잠재적 자원 수요와 노동력 공급을 위한 기초정보를 제공한다. 정확한 장래인구를 추계하는 것은 국가 및 중앙정부 뿐 아니라 지방정부 혹은 그보다 규모가 작은 기초자치단체도 미래의 사회적 변화에 대응하고 지역 특성에 알맞은 정책을 마련하기 위하여 중요한 일임에 틀림없다. 우리나라의 경우 장래인구추계는 통계청에서 담당하고 있는데 현재까지 국가 및 시도단위의 장래인구추계 결과를 발표하고 있으며 기초자치단체는 인구추계의 대상에서 제외되어 있다. 이 글은 Hamilton과 Perry에 의해서 최초 개발되어 실제 미국의 소규모지역별 장래인구추계에 사용되어 온 추계기법을 사용하여 한국의 기초자치단체에의 적용가능성에 대해 검토해 본 연구이다. 장래인구추계를 위한 H-P기법은 도시와 농촌지역의 기초자치단체에 각각 적용해 본 결과 통계청에서 주로 사용하고 있는 코호트 조성법을 이용한 추계기법보다 단순하고 추계를 위해 필요한 정보도 쉽게 얻을 수 있으면서도 비교적 정확한 추계결과를 제시하였다.

• Journal of the Korean Data and Information Science Society
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• v.23 no.1
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• pp.71-77
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• 2012

This paper introduces the projection methods by nonlinear regression model. To predict the student numbers, a log model and an involution model as the kind of a trend-extrapolation method are used. Empirical evidence shows that a projection by log model is better than by involution model with the confidence interval estimations for the coefficients of determination.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1167-1173
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• 2011

The goal of this paper is to suggest an algorithm to get forecasting for the numbers of students in the city or county in local government by using the double exponential smoothing method. By 2044 year, the third year of high school students in the Chilgok, Gumi, Gyeongsan, Andong, Pohang and Gimchen are reduced about 40-70%, the those of in the remaining city or county are reduced about 70-95%. In conclusion, the forecasting numbers of students of the 23 counties in Kyungbuk Province are on the decrease to 40%-100% until 2044 year in comparison with the numbers of students on 2010 years.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.37-44
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• 1992

Annual biomasses of small yellow croaker, Pseudosciaena polyactis, were estimated by biomass-based cohort analysis (Zhang, 1987) , using data on annual catch in weight at age for 1970-88 in Korean waters. Annual biomass of croaker was highest in 1974 with about 100,000 mt, declining to a level of 20,000-30,000 mt after 1981. Adult biomass also showed a peak in 1974 with about 50,000 mt. Afterwards, however, it continuously dropped. According to the estimates of biomass at age obtained from this analysis, the age composition of small yellow croaker in the 1980's differed greatly from that in the 1970's. The proportions of older croakers (>5 years) were very low in the 1980's and even the biomasses of young croakers (1-4 years) were at a very low level in the 1980's. Year classes of 1968, 1972 and 1978 appeared to be relatively dominant. The mean value of instantaneous fishing mortality (F) in the 1980's was twice that of the 1970's. Recruitment of croaker exhibited an unusally linear relationship with adult stock biomass.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.620-626
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• 1997

Annual biomasses of the hairtail, Trichiurus lepturus, were estimated from the biomass-based cohort analysis (Zhang, 1987), using data of annual catch in weight at age during $1970\~1988$ in Korean waters. Annual biomass of the hairtail was peaked at about 240,000 mt in 1975, and thereafter declined with a slight fluctuation. Adult biomass showed a peak in 1978 with about 55,000 mt. However, it has continuously decreased untill 1980 to the level of 9,000 mt and remained at this level till 1988. Age compositions of the hairtail in the 1980s differed greatly from those in the 1970s. The proportions of older hairtail (>4 years) were very low in the 1980s and even the biomasses of young hairtail $(1\~3\;years)$ were at a low evel in the 1980s compared with the level in 1970s. The 1973 and 1974 year classes appeared to be relatively dominant. The mean value of instantaneous rate of fishing mortality (F) in the 1980s was significantly different from that of the 1910s (P<0.05). Recruitment of the hairtail exhibited a similar trend with stock biomass until 1974, indicating the density-dependent Ricker curve.