• 한국시스템다이내믹스학회:학술대회논문집
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• 한국시스템다이내믹스학회 2006년도 춘계학술대회 발표논문집
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• pp.101-122
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• 2006

A series of system dynamics model was developed for forecasting demand and supply of human resource in the electricity industry. To forecast demand of human resource in the electric power industry, BLS (Bureau of Labor Statistics) methodology was used. To forecast supply of human resource in the electric power industry, forecasting on the population of our country and the number of students in the department of electrical engineering were performed. After performing computer simulation with developed system dynamics model, it is discovered that the shortage of human resource in the electric power industry will be 3,000 persons per year from 2006 to 2015, and more than a double of current budget is required to overcome this shortage of human resource.

• 한국인구학
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• 제8권2호
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• pp.46-67
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• 1985

In this paper, an attempt has been made to examine the pattern of mortality in Korea during 1970~80. By applying the age-sex specific mortality rates quoted from 1978~79 life tables for Korea published by NBOS, EPB to those of the West pattern of regional model life tables and the far eastern pattern of model life tables for developing countries, life expectancy at birth were calculated. Also the author reviewed the trends of death rates, life expectancy and cause of death using vital registration data and other materials. Summarized results are as follows; 1. Crude death rates in Korea was reduced to one fifth in the 1983 compared to that in 1920's. Life expectancy also improved to almost double in 1985 compared to 1920's. But the difference in the life expectancy between male and female increased during that period and it was recorded as 6.4 years in 1985. This discrepancy was mainly due to the different tempo of decreasing in mortality level by sex, particularly, for the age 40 and above. 2. For the pattern of mortality in Korea, it showed that female mortality could accounted closer to the West pattern model life tables. There were high similarity between actual pattern prevalent in Korea and West pattern. And its coefficient of variance was also very low. However for the case of male, it was difficult to find the exact model life tables for explaining the actual situation on the male mortality pattern which means exist considerable dissimilarity in older ages. The Far eastern pattern of U.N. model life tables show better results than West pattern, however, the deviation of the pattern to actual was severe. Also in Far eastern pattern, high coefficient of variance was existed. Furthermore it was found in the paper that the mortality level of Korean male for the age 40 and above were much higher than that of Far eastern pattern which was reflected the high mortality of the male adult in Far east region. 3. The analysis of cause of death showed that circulatory disease such as cerebrovascular disease and hypertensive disease accounted for the leading cause of death in Korea for the age 40 and above. There should he paid special attention to chronic retrogressive diseases for the older age groups. For younger age groups, injury and poisoning were reported as important cause of death.

• 한국조경학회지
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• 제26권3호
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• pp.90-103
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• 1998

The purposes of this study are to estimate the economic value and reasonable entrance fee of the Yeido Park, which is under construction in Seoul, by conduct the face-to-face interview. A total of 645 daults were selected by two stage cluster sampling. The senario was designed to meet the requirements for doubgle-bounded dichotomous choice CVM, and distributed with the photograph to epict and compare the current and suggested conditions. A donation vehicle and entrance fee were utilized to find the possibility of strategic behaviors and protest zero, and to make the data estimatable tfor interval censored survival analysis. Date was calibrated by the survival analysis to eleminate the 'fat-tail problem'. Weibull distribution was assumed as a baseline distrubution. The mean WTP of donation and entrance fee was ￦5,281 and ￦783, respectively. The economic value of this park was determined by aggregating the mean value, giving a total WTP for the population of ￦36,861,645,000. This economic value was composed with the use value and existence value. The calibrationi of the Weibull proportional hazard model showed that nearness to the park, age, intention to isit the park, and educational attainment were significant independent variable to influence an amount of donation.

• 상하수도학회지
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• 제28권5호
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• pp.561-571
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• 2014

The paper is to estimate willingness-to-pay (WTP) for tap water quality improvement in Busan, using parametric approach in contingent valuation method(CVM). For parametric approach linear logit model and log logit model are employed in double-bounded dichotomous choice format of CVM. For the reliability and the validity of contingent valuation method a survey was conducted for 665 respondents, who were sampled by stratified random sampling method, by personal interview method. The result of mean WTP for the tap water quality improvement in Busan was estimated to be 3,687 won and 3,660 won per month per household, while median WTP being 1,884 won and 1,892 won per month per household, respectively by linear logit model and log logit model. Provided that our sample is broadly representative of the Busan's population, an estimate of the annual aggregated benefit of residential water improvement for all Busan households is approximately 29.7 billion won to 29.8 billion won based on median WTP.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.391-394
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• 2006

In this paper, the thermal lattice Boltzmann method(TLBM) proposed by Guo et al.(2002) is applied to analyze the forced convective flow and heat transfer of 2-D micro channel. Nonequilibrium extrapolation boundary condition is adopted to simulate the velocity and temperature behavior at wall boundaries. Numerical results obtained by the present study give a good prediction of the micro fluidic characteristics with thermal effects.

• 응용통계연구
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• 제17권2호
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• pp.303-310
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• 2004

본 연구에서는 민감한 모집단에 대한 자료수집 방법으로 직접 질문 방법 인 Black-Box 방법과 간접 질문 방법인 확률화응답기법(RRT)의 결합적 방법을 제시하였고, 층화이중추출방법을 이용하여 모수를 추정하였다. 또한, 주어진 추정량의 효율성을 Mangat과 Singh 추정량과 비교 분석하였다.

• 한국산림과학회지
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• 제90권4호
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• pp.573-581
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• 2001

본 연구는 산불재해 방지기금을 지불수단(payment vehicle)으로 한 2단계(二段階) 2선(二選) 가상가치추정법(double-bounded dichotomous choice DVM)을 사용하여 산불예방을 위한 서울 시민의 평균 지불의사 금액과 금액에 영향을 미치는 변수들의 영향력 정도를 정산하였다. 자료는 19~59세의 서울시민들 중에서 2단계 군집표본추출 방법으로 선택된 500명을 대상으로 개별 대면 면접하여 수집하였다. 분석결과 면접대상인 서울시민의 과반수(64.6%)가 산불재해 방지기금에 대한 지불의사가 있었다. 이들의 평균 지불의사금액은 7,016원이였으며, 지불의사가 없는 응답자들을 포함하면 평균 4,532원이었다. 이를 근거로 19세부터 59세까지의 전체 서울시민들의 총 지불의사금액은 34,165,758,000원으로 집계되었다. 관련변수의 지불의사금액에 대한 영향력을 와이블 비례위험함수 모형(Weibull proportional hazard model)으로 검토한 결과, 교육수준이 높을수록, 환경보존에 대한 필요성을 크게 느끼는 사람들일수록, 또한 산불로 인한 영향을 부정적으로 볼수록 높은 것으로 나타났다.

• 한국대기환경학회지
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• 제4권1호
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• pp.45-57
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• 1988

This is a close relationship between energy consumption and the way in which we develop and manage our regions. This study has estimated and compared energy requirements for the journey to work, resulting from alternative population and employment growth patterns in a rural-urban regional settlement of Korea. The broad scope of work was as follows: i) Select the study area ii) Formulate alternative growth patterns iii) Develop the Hansen and double-constrained gravity model iv) Application of Vogel's approximation method and the developed Hansen and gravity model to the case study area. v) Analyze the relationship between spatial structure, transport energy-requirements and environmental pollution. At issue here is the trade-off between air pollution averages and variations. Policies concentrating manufacturing industry and other regional facilities, for instance, may indeed reduce average pollution levels at the benefit of less-car miles, thus, reducing auto pollution, in the region, but increase local pollution peaks.

• 환경생물
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• 제20권3호
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• pp.256-262
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• 2002

생태계를 평가하기 위한 평가법으로 주로 사용되는 이화학적 측정 평가법은 객관적인 측정치를 제시하는데는 용이하다. 그러나 단지 측정치의 단순한 평균이나 최고치만으로는 타 인자와의 복합 효과 또는 지속 시간에 의한 가중 효과 때문에 실상을 나타낼 수 없는 경우가 많다. 이에 따라 이화학적 측정치들을 객관적으로 종합하여 생태계의 상태를 파악할 필요성이 보다 중요하다. 즉 key factor나 trigger factor와 같은 생물체의 내성과 관련이 있는 인자들로 종이나 생태계의 조절 기구와의 관계를 평가해야 한다. 또한 생물을 이용하여 생태계를 평가하는 방법으로 지표종을 이용한 평가방법이 있으나 오염원에 대한 누적 효과나 종합적인 평가를 판단하는데는 한계성이 있다. 따라서 생태계를 하나의 단위로 하는 평가 방법 이 필요하다. 이에 따라 본 실험은 생산자, 분해자, 소비자로 구성된 microcosm이용하여 대표적인 산업폐수인 도금공장 폐수에 대한 독성을 평가하였다. 그 결과 도금 폐수의 이화학적 성상은 크롬 42,234.8mg\ell^{-1}$, 구리 3.1mg\ell^{-l}$, 아연 $521.3mg\ell^{-1}$로 크롬이 다량 함유되어 있었으며, 시안은 $42.9mg\ell^{-1}$이었다. 도금 폐수를 농도별로 microcosm 내에 첨가한 후 각 개체군들의 동태 변화를 조사한 결과 Ch. vulgaris는 모든 처리구에서 대조구보다 감소하는 경향을 나타내었고, P. putida는 대조구에 비해 증가하였으며, C. glaucoma는 농도가 증가함에 따라 개체수가 감소하기 시작하였으며, 2.5%이상의 처리구에서는 모든 개체수가 사멸하였다. 본 연구 결과 제어된 생물환경 조건하에서 구성된 microcosm이 실험 재현성이 비교적 우수하고, 안정된 미소 생태계를 유지할 수 있어 산업 폐수 및 오폐수에 대한 새로운 독성평가 방법으로 적용이 가능할 것으로 본다.

• Molecules and Cells
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• 제41권1호
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• pp.35-44
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• 2018

Mitochondria are responsible for supplying of most of the cell's energy via oxidative phosphorylation. However, mitochondria also can be deleterious for a cell because they are the primary source of reactive oxygen species, which are generated as a byproduct of respiration. Accumulation of mitochondrial and cellular oxidative damage leads to diverse pathologies. Thus, it is important to maintain a population of healthy and functional mitochondria for normal cellular metabolism. Eukaryotes have developed defense mechanisms to cope with aberrant mitochondria. Mitochondria autophagy (known as mitophagy) is thought to be one such process that selectively sequesters dysfunctional or excess mitochondria within double-membrane autophagosomes and carries them into lysosomes/vacuoles for degradation. The power of genetics and conservation of fundamental cellular processes among eukaryotes make yeast an excellent model for understanding the general mechanisms, regulation, and function of mitophagy. In budding yeast, a mitochondrial surface protein, Atg32, serves as a mitochondrial receptor for selective autophagy that interacts with Atg11, an adaptor protein for selective types of autophagy, and Atg8, a ubiquitin-like protein localized to the isolation membrane. Atg32 is regulated transcriptionally and post-translationally to control mitophagy. Moreover, because Atg32 is a mitophagy-specific protein, analysis of its deficient mutant enables investigation of the physiological roles of mitophagy. Here, we review recent progress in the understanding of the molecular mechanisms and functional importance of mitophagy in yeast at multiple levels.