• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.151.1-151.1
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• 2010

Natural gas hydrates (NGH) provide 170 gas volumes per unit volume of the medium and are easier to make with moderate pressure and temperature (40 bar at 3 C). Once they form, their preservation temperature is 20 C at 1 bar, which is much milder than the LNG preservation. In case of using the NGH, The small and medium sized gas well has advantages for development because of NGH's these characteristics. According to the cost evaluation report of Gudmundsson in Norway and the research of MES in Japan, the gas well that uses the NGH has a cost saving effect about 10~20% compared LNG. The effect depends on distance and production. However, cost saving and efficiency of liquefaction process is increased by the development of LNG liquefaction technology. Therefore, these factors have to be reflected in economic analysis. The purpose of this research is to compare the cost of Gas Supply Chain according to the transport type, distance and gas reserves. Especially, we consider not only the cost of facility but also the total cost (production cost, transport cost, etc).

• 청정기술
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• 제29권1호
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• pp.53-58
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• 2023

This study shows the summary of the economic performance of excess electricity conversion to hydrogen as well as methane and returned conversion to electricity using a fuel cell. The methane production process has been examined in a previous study. Here, this study focuses on the conversion of methane to electricity. As a part of this study, capital expenditure (CAPEX) is estimated under various sized plants (0.3, 3, 9, and 30 MW). The study shows a method for economic optimization of electricity generation using a fuel cell. The CAPEX and operating expenditure (OPEX) as well as the feed cost are used to calculate the discounted cash flow. Then the levelized cost of returned electricity (LCORE) is estimated from the discounted cash flow. This study found the LCORE value was ¢10.2/kWh electricity when a 9 MW electricity generating fuel cell was used. A methane production plant size of 1,500 Nm³/hr, a methane production cost of $11.47/mcf, a storage cost of $1/mcf, and a fuel cell efficiency of 54% were used as a baseline. A sensitivity analysis was performed by varying the storage cost, fuel cell efficiency, and excess electricity cost by ±20%, and fuel cell efficiency was found as the most dominating parameter in terms of the LCORE sensitivity. Therefore, for the best cost-performance, fuel cell manufacturing and efficiency need to be carefully evaluated. This study provides a general guideline for cost performance comparison with LCORE.

• Current Research on Agriculture and Life Sciences
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• 제3권
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• pp.55-61
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• 1985

양계 및 양돈용 배합사료중 pellet 사료와 분말사료의 생산비를 비교하였다. 비교분석을 위하여 박(1982)이 개발한 모형을 이용하였으며 공장의 규모는 일산 80ton으로부터 400ton이었다. 분석된 결과를 요약하면 다음과 같다. 1. 동력비는 pellet 사료가 분말사료에 비해 4배가 높았다. 2. 노동비는 pellet 사료가 분말사료에 비해 20%가 높았다. 3. 일산 200ton 규모의 경우 투자비용은 pellet 사료가 20% 높았다. 4. 고정비 및 변동비를 고려한 총생산비를 공장규모가 100ton에서 400ton으로 커질 경우 pellet 사료가 분말사료에 비해 30%에서 50%로 증가되었다.

• Journal of Biosystems Engineering
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• 제19권4호
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• pp.343-357
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• 1994

Current commercial dairy feed has various problems in low feed productivity, inadequate formulation and higher feeding cost due to excessive capital investment and non-specialized system for the end product. To solve those problems, 6 TMR terminal models were developed in this study. The developed TMR terminal system consists of TMR terminal, TMR main center and combined system linked TMR terminal and TMR main center. 15 TMR main center models were developed to support 10, 20, 30, 40, 50 TMR terminal(30 ton/day basis) by 3 different types, and evaluated for capital investment and operation cost by the analysis of the newly developed computer program. Optimum model size is analyzed and suggested for each model. Followings are summary of this study : 1. The capital investment costs of TMR main centers were 1,600 to 3,800 million won for type 1, 2,200 to 4,500 million won for type 2 and 2,200 to 4,800 million won for type 3. Also model MACE30 or bigger were justified as the economical models. 2. The feed production costs of TMR main center models were 3,166 to 4,824 won/ton for type 1, 3,816 to 6,182 won/ton for type 2 and 3,990 to 6,263 won/ton for type 3. So feed production cost range was 3,166 to 6,263 won/ton. 3. The bigger production capacity, the less TMR main center production cost. The feed production cost of the biggest model MACE50 was 62~65% of smallest model MACE10.

• 오토저널
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• 제14권6호
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• pp.113-126
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• 1992

Recently the multi-kind, small-amount manufacturing system has been replacing the mass manufacturing system, and domestic machining inustry also is eager to absorb the new technology because of its high productivity and cost reduction. The optimization of the cutting condition has been a vital problem in the machining industry, which would help increase the productivity and raise the international competitiveness. It is intended in this study to investigate the machining costs per unit time which is essential to the analysis of the optimal cutting condition, to computer the cutting speed that lead to the minimum machining costs and the maximum production to suggest the cutting speed range that enables efficient speed cutting, and to review the machining economy in relation to cutting depth and feed. Also considered are the optimal cutting speed and prodution rated in rrelation with feed. It is found that the minimum-cost cutting speed increases and the efficient cutting speed range is reduced as machining cost per unit time increases since the cutting speed for maximum production remains almost constant. The machining cost is also lowered and the production rate increases as the feed increases, and the feed should be selected to satisfy the required surface roughness. The machining cost and production rate are hardly affected by the cutting depth if the cutting speed stays below 100m/min, however, they are subject to change at larger cutting depth and the high-efficient speed range also is restricted. It can be established an adaptive optimal cutting conditions can be established in workshop by the auto-selection progam for optimal operation. It is expected that this method for choosing the optimal cutting conditions might contribute to the improvement of the productivity and reduced the cost. It is highly recommended to prepare the optimal cutting conditionthus obtained for future use in the programing of G-function of CNC machines. If proper programs that automatically select the optimal cutting conditions should be developed, it would be helpful to the works being done in the machine shops and would result in noticeable production raise and cost reduction.

• 공업화학
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• 제29권2호
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• pp.209-214
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• 2018

본 논문에서는 $300m^3\;h^{-1}$급 수소 생산을 위한 글리세롤 수증기 개질반응에 대해 기술 경제성 평가를 수행하였다. 상업용 공정 설계 프로그램인 Aspen $HYSYS^{(R)}$를 이용하여 글리세롤 수증기 개질반응에 대한 공정을 설계하였으며, 반응온도에 따른 수소 생산량의 차이를 비교 분석하였다. 또한, 항목별 경제성 평가, 민감도 분석, 현금흐름도를 통하여 경제성 평가를 진행하였으며, $300m^3\;h^{-1}$급 글리세롤 수증기 개질반응에서의 수소 생산 단가는 5.10 $ ${kgH_2}^{-1}$로 계산되었다. 수소 생산 단가에 영향을 끼치는 주요 인자를 파악하기 위해 민감도 분석을 실시하였으며, 수소 판매 단가에 따른 현금흐름도 분석을 통해 순현재가치, 할인회수기간, 현재가치율과 같은 다양한 경제성 인자를 파악하였다.

• 소성∙가공
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• 제19권8호
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• pp.523-528
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• 2010

The forging industry is composed of those plants that make parts to order for customers; or make parts for their own company's internal use; or make standard parts for resale. Also, the forging industry is closely related with automobile industry and ship building industry - Korea's major export industry. But, it is hard to find the Korea's forging industry's statistical analysis because it is not revealed with final product. In this paper, we perform statistical analysis using the micro data service provided by the Statistics Korea. We focus on the analysis of production costs as well as the status of forging company and their employee.

• 대한영양사협회학술지
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• 제2권2호
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• pp.123-140
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• 1996

The purpose of this study was to examine financial management practices in elementary school foodservices. Respondents were asked to provide information on demographics, operational characteristics, financial management activities(responsibility, importance and time demand). Data were collected from 106 elementary school foodservice using the mail questionnaire. The results were as follows 1. Time demand of 14 financial management activities was examined. The results of time-demand showed that most financial activities were performed about once per month. Reporting, inventory checking and production cost accounting were performed several times per week. 2. Major financial management activities performed by school dietitians were inventory checking, record keeping, production cost accounting, and foodservice operation planning. 3. Results of the importance rating of 14 financial management activities showed that the production cost accounting, budgeting, controlling meal costs, reporting the national treasury accounts, and inventory checking were rated as very important(4.00-4.49). Factor analysis was conducted on the importance ratings. Five activities were differentiated such as budgeting, record keeping, cost controlling, cost accounting, and reporting. The cost controlling task was identified at the most important one among them. 4. Important ratings for reporting were found to be significantly different by age, and years of experience. The younger and the less experienced were responded with higher scores on reporting. Analysis of variance for the importance scales by meal costs per one person, food cost percentage, labor cost percentage was conducted, but significant differences were not founded.

• 산업경영시스템학회지
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• 제18권35호
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• pp.131-138
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• 1995

For the purpose of the reduction of tile cost, a production/inventory model including the interference phenomenon was developed. By investigating the cause and the characteristics of the direct/indirect cost due to the interference phenomenon, a strategy for suitable production was developed. The developed model was quantitatively validated using an existing-EPQ model and the SIMAN package was used to simulate and animate the model. Consequently, it was presented that the total operating cost of the system could be decreased with tile proposed model.

• 대한공간정보학회지
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• 제15권1호통권39호
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• pp.67-73
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• 2007

최근 여러 측면에서의 효용성 및 다양한 분야에서의 활용 가능성이 높게 평가되고 있는 LiDAR 시스템을 이용하여 취득한3차원의 지형공간정보는 수치지도 제작, 3차원 건물 및 도시모델링, 통신환경 분석 등 많은 분야에서 응용되고 있다. 이에 본 연구에서는 최신의 항공LiDAR 측량 기술을 이용하여 기존 항공사진 측량 기술에 의한 수치지도 제작 기법을 대치할 수 있는 여러 가지 요소 중 가장 기초적인 경제적 비용 부분을 분석하였다. 이는 향후 수치지도의 수정 갱신 및 제작을 위한 항공 LiDAR 측량의 적용성을 판단하는 중요한 기초 자료가 될 것이며, 나아가 국가의 예산절감 효과를 거두는 근거자료로 활용될 수 있을 것이다.