• 한국환경과학회지
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• 제22권3호
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• pp.281-289
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• 2013

For the purpose of evaluating the eco-efficiency(EE) on surplus heat generated from industrial process, techniques of life cycle assessment are adopted in this study. Because it can be indicated both environmental impacts and economic benefits, EE is well known as a useful tool for symbiosis network on the sustainable development of new projects and businesses. To evaluate environmental impacts, the categories were divided into two areas of resource depletion and global warming potential. It can be seen that environmental impact increased a little but much higher economic benefit on the company, environmental performance and economic value were improved on the apartment by the district heating, respectively. In result, eco-industrial park(EIP) project on surplus heat should be found sustainable new business because the EE was in the area of fully positively eco-efficiency and, moreover resource depletion was taken place than the reduction of greenhouse gas.

• Journal of Biosystems Engineering
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• 제37권1호
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• pp.19-27
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• 2012

Purpose: Utilizing air thermal energy during over-heated time in the greenhouse is a necessary component to save greenhouse heating costs for nighttime. However, there is no practical way to implement the related principles. Methods: In this study, a heating and cooling system which utilizes the surplus air thermal energy in a greenhouse was developed. Available air thermal energy and heating load for this experimental glasshouse were estimated based on temperature conditions of the plant growth and weather data. Results: Estimated values were 400 MJ/day for maximum surplus air thermal energy and 340 MJ/day for maximum heating energy which were target values of the design as well. The system consists of a heat pump, fan-coil units and heat storage tanks which are divided into low and high temperature tanks. Moreover, a new control logic was developed for surplus air thermal energy utilization. Conclusions: This paper explains the details of conceptual design process of the system. Results of test operations showed that the developed system performed the recovery and supply of the thermal energy according to design purposes.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권5호
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• pp.609-616
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• 2018

The cargo handling system, which is composed of a fuel gas supply unit and cargo tank pressure control unit, is the second largest power consumer in a Liquefied Natural Gas (LNG) carrier. Because of recent enhancements in ship efficiency, the surplus boil-off gas that remains after supplying fuel gas for ship propulsion must be reliquefied or burned to regulate the cargo tank pressure. A full or partial liquefaction process can be applied to return the surplus gas to the cargo tank. The purpose of this study is to review the current partial liquefaction process for LNG carriers and develop new processes for reducing power consumption using exergy analysis. The developed partial liquefaction process was also compared with the full liquefaction process applicable to a LNG carrier with a varying boil-off gas composition and varying liquefaction amounts. An exergy analysis showed that the Joule-Thomson valve is the key component needed for improvements to the system, and that the proposed system showed an 8% enhancement relative to the current prevailing system. A comparison of the study results with a partial/full liquefaction process showed that power consumption is strongly affected by the returned liquefied amount.

• 한국의류산업학회지
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• 제13권2호
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• pp.269-278
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• 2011

This study aims at setting up productive capacity which can be usefully utilized for work management of apparel manufacturers. So as to achieve this goal, an apparel manufacturing company which has been operated by miniline system in Seoul was selected. Standard time and man-hour were calculated to create the accurate productive capacity by observing and measuring a work flow included cutting, sewing and finishing processes. And the result is as following. The standard time for each process was presented as cutting process 47004.5s, sewing process 671050.5s and finishing process 22426.3s. And 15284.4ms was computed as total procession man-hour per day of the manufacturer which is organized of 16 people. Also, the procession man-hour for each process was revealed as cutting process 396.7ms(2.6%), sewing process 14509.3ms(94.9%) and finishing process 378.5ms(2.5%). +Surplus was found in the productivity for each process included the cutting process(outshell, lining and seam process), the sewing process(preparation and arrangement process) and the finishing process. But, additional man-hour 52436.18ms was required because the productive capacity was calculated as -surplus(-13.9%) in the sewing process(part and assembly process). Therefore, a work schedule was planned based on the previous result. However, loading can be ideal when a capacity and a load become '0'. The object company should find the way to reduce allowance(26.25%) of the sewing process through reconstruction of consciousness and improvement in functions with analyzing works of operators. Also, they need to consider an additional supplement of the personnel.

• 대한지리학회지
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• 제32권2호
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• pp.229-244
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• 1997

개혁 이전에 정책적으로 강력히 억제된 중국의 도시화는 개혁 이후 상품 경제의 발달로 변화되었다. 그 과정에서 농촌 중심지인 소성진이, 급격한 도시화를 막고 농업부문의 잉여노동력을 흡수할 수 있는 역할이 부각되어 양적ㆍ질적인 성장을 하였다. 소성진은 농업부문의 구조조정, 농촌 공업화의 규모화, 잉여 노동력의 해소의 역할을 하면서 한편으로는 왜곡된 중국 취락 체계의 회복과 상품경제로 성장한 농촌주민들의 도시 진입 욕구를 해결하는 도구로서 작용하였다. 소성진화 과정은 비록 과도적 단계이지만 공간 정책을 통해 전반적인 사회의 혼란을 최소화하는 긍정적인 역할을 수행하고 있다.

• 한국축산식품학회지
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• 제27권4호
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• pp.517-521
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• 2007

Questionnaire on utilization of colostrum was carried out in 33 farms. Highest milking cow numbers were 20-40 heads in 45.5% of the farms. Calf numbers were 20-40 heads in 39.4% of the dairy farms and 40-60 heads in 42.4% of the farms. The amount of colostrum production per day was 20-30 kg in 30.3% of the farms and 30-40 kg in 30.3% of the farms. Colostrum intake per calf per day was 4 kg in 45.5% farms. Surplus colostrum after intake by calf was farms (85%) was wasted in 67% of the farms. More than 90% of dairy farms recognize an necessity to use surplus colostrum. Selling price of surplus colostrum was below 1,000 won per kg at 15 dairy farms and 1,000-2,000 won per kg at 4 dairy farms. Colostrum collection and use should be done by the dairy farms of antibiotics free. Quality control of colostrum should be done by testing antibiotics, microbacterium, chemical composition, somatic cells and etc. The colostrum is subjected to cool down below $4^{\circ}C$ just after milking and process for the colostrum products.

• 한국지반신소재학회논문집
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• 제22권2호
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• pp.63-70
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• 2023

부산 및 경남지역의 산업단지 및 주택단지 조성은 일부 매립 지역을 제외한 대부분이 산지를 개발하여 형성되었다. 단지 개발과정에서 부지조성을 위한 산지 현장 발생토를 성토재료로 주로 사용하고 있다. 하지만 현장에서는 부지조성을 위한 성토작업 시 재료의 재질이 변화하여도 시공기간 및 현장여건 등의 편의상의 이유로 성토 재료에 대하여 물성시험 및 다짐시험을 추가적으로 실시하지 않고 품질관리를 하고 있는 실정이다. 본 연구에서는 부산 및 경남지역 산지 현장 발생토에 대한 물성시험 및 다짐시험을 실시한 후 회귀분석을 실시하였다. 그리고 국내의 기존연구와 비교 분석하였다. 부산 및 경남지역 현장 발생토는 주로 화강암류의 풍화토로서 점토질모래(SC) 및 실트질모래(SM)으로 분류되며, 조립토 및 세립토의 함유량에 따른 다짐특성을 회귀분석한 결과 상관성이 매우 높은 것으로 나타나 금 번 연구결과 관계식을 활용하면 현장 발생토의 다짐관리 시 매우 유용하게 활용될 수 있을 것이다.

• 한국주거학회논문집
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• 제12권4호
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• pp.93-104
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• 2001

This study has been performed to analyze size and deficit problem of residential space in later life. In this study, 216 Koreans aged 50 to 79 were surveyed for their current residential space ad family related items such as age, marital status, living arrangement, birth order, and housing status. The results are drawn as follows: 1. The space size significantly fluctuates by marital status, number of generations living together, tenure, and structure type; For example, use of indoor area per person ranges from 7.01 pyoung for three-generation households to 19.53 for one-generation households. 2. s for space deficit, very old widowed females, 60's living in rented or multi-family housing units, and those living in three generations are high risk groups of the space deficit below 7 young per person. In this study, further researches are recommended as follows; Regarding the highest risk group of space deficit, life styles causing space-related conflicts should be studied, and accordingly proper welfare services for the causal life styles be offered. Housing maintenance & utility costs be investigated and guidelines should be proposed for any surplus groups among the 60's, so that their space surplus can be reduced by suitable adjustment process.

• Communications for Statistical Applications and Methods
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• 제18권4호
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• pp.433-443
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• 2011

잉여금의 수준에 따라 이단계의 보험요율이 적용되는 복합 포아송 위험 모형을 고려한다. 먼저 이 위험 모형에 대응되는 이단계 서비스율의 M/G/1 대기행렬 모형을 설정하고, M/G/1 대기행렬 모형에서 작업량이 0에 도달하기 전에 과부하가 발생하는 확률을 유도한다. 이과부하 확률을 이용하여 위험모형에서 잉여금이 목표값에 도달하기 전에 파산하는 확률을 구하고, 보험 청구액이 지수분포를 따르는 경우의 파산 확률을 계산한다.

• Fisheries and Aquatic Sciences
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• 제24권4호
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• pp.139-152
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• 2021

The main purpose of this study is to fit catch-per-unit-effort (CPUE) data about Korea chub mackerel (Scomber japonicus) stock with a state-space production (SSP) model, and to provide stock assessment results. We chose a surplus production model for the chub mackerel data, namely annual yield and CPUE. Then we employed a state-space layer for a production model to consider two sources of variability arising from unmodelled factors (process error) and noise in the data (observation error). We implemented the model via script software ADMB-RE because it reduces the computational cost of high-dimensional integration and provides Markov Chain Monte Carlo sampling, which is required for Bayesian approaches. To stabilize the numerical optimization, we considered prior distributions for model parameters. Applying the SSP model to data collected from commercial fisheries from 1999 to 2017, we estimated model parameters and management references, as well as uncertainties for the estimates. We also applied various production models and showed parameter estimates and goodness of fit statistics to compare the model performance. This study presents two significant findings. First, we concluded that the stock has been overexploited in terms of harvest rate from 1999 to 2017. Second, we suggest a SSP model for the smallest goodness of fit statistics among several production models, especially for fitting CPUE data with fluctuations.