• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2000년도 춘계학술대회 논문집
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• pp.57-66
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• 2000

Production-distribution planning is the most important part in supply chain management (SCM). To solve this planning problem, either analytic or simulation approach has been developed. However these two approaches have their own demerits in problem solving. In this paper, we propose a hybrid approach which is a specific problem solving procedure combining analytic and simulation method to solve production-distribution problems in supply chain. The machine capacity and distribution capacity constraints in the analytic model are considered as stochastic factors and adjusted by the proposed specific process according to the results from independently developed simulation model which includes general production-distribution characteristics.

• 식물병연구
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• 제21권3호
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• pp.231-234
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• 2015

Elsinoe fawcettii and E. australis are two currently recognized scab pathogens of citrus. E. fawcettii has at least six pathotypes while E. australis has at least two pathotypes. Colonies of E. fawcettii and E. australis do not sporulate in artificial media including potato dextrose agar (PDA). Whiteside's method has been widely used for preparing conidial inoculum in vitro. This study was carried out to develop efficient method for conidia production from artificial media. We developed a shaking method which included the following steps: 1) Colony grown on PDA was mashed with a steel spatula; 2) Mycelia fragments were cultured in 50 ml sterilized rain water in a rotary shaker-incubator (180 rpm) at $25^{\circ}C$ for 24 h: 3) The conidia suspension was filtered through two layers of cheesecloth. Average conidia production of all isolates tested using this shaking method was approximately 13.1 times higher than that from Whiteside's method in this study.

• 산업경영시스템학회지
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• 제38권3호
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• pp.159-168
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• 2015

Aggregate Production Planning determines levels of production, human resources, inventory to maximize company's profits and fulfill customer's demands based on demand forecasts. Since performance of aggregate production planning heavily depends on accuracy of given forecasting demands, choosing an accurate forecasting method should be antecedent for achieving a good aggregate production planning. Generally, typical forecasting error metrics such as MSE (Mean Squared Error), MAD (Mean Absolute Deviation), MAPE (Mean Absolute Percentage Error), and CFE (Cumulated Forecast Error) are utilized to choose a proper forecasting method for an aggregate production planning. However, these metrics are designed only to measure a difference between real and forecast demands and they are not able to consider any results such as increasing cost or decreasing profit caused by forecasting error. Consequently, the traditional metrics fail to give enough explanation to select a good forecasting method in aggregate production planning. To overcome this limitation of typical metrics for forecasting method this study suggests a new metric, WACFE (Weighted Absolute and Cumulative Forecast Error), to evaluate forecasting methods. Basically, the WACFE is designed to consider not only forecasting errors but also costs which the errors might cause in for Aggregate Production Planning. The WACFE is a product sum of cumulative forecasting error and weight factors for backorder and inventory costs. We demonstrate the effectiveness of the proposed metric by conducting intensive experiments with demand data sets from M3-competition. Finally, we showed that the WACFE provides a higher correlation with the total cost than other metrics and, consequently, is a better performance in selection of forecasting methods for aggregate production planning.

• 한국유기농업학회지
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• 제1권
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• pp.19-28
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• 1992

The definitions of organic farming method has rather philosophical meaning than application of agricultural practices. The meaning of organic farming method has certainly basic differences in comparison with the conventional farming methods. The main definitions of organec farming method have certainly to reduce or not to apply any kinds of farm inputs materials by increasing quality of agricultural prod-ucts. However, the quality of produced food by organic farming method should be improved in compari-son with cinvethional farming method. By applying organic method, the qualith of food, envir-onment as well as spiritual attitude of human being should be improved in future. Actually, there are very wide fields of research on organic farming methods such as production tech-niques, soil and water conservation, plant and animal production, marketing and consumers behavior on organic products. In this article the present situation of organic farming methods in the United States of Americal is investigated in cimparison with conventional rice production. The production cost of rice per acre in the United States of America mde 58, 788 Won in 1986, while it was 121, 699 Won in Korea having about 107 percent higher in Korea than tham the U.S.A There is a larger rice farm cost analysis between conventional and organic rice farm in California. The cash cost pre 1 lbs of conventional rice made 4.86 $, while the organic rice was 6.96$ showing about 43.2%higher level of cost in organic products(1 lbs=0.45359kg) At present, there is less econmic advantage of organic rice production in California because of lower yields as well as price levels, Therefore, the total net return over cash cost peracer/yeat was a little lower in organic rice production than conventional rice prouction.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2338-2343
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• 2007

The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method for data collection and data analysis was used in the cellular phone module production lines. And this method was evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. From these results, it is concluded that the partition check method is effective solution for particle contamination control in the cleanroom production lines.

• 품질경영학회지
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• 제42권3호
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• pp.311-324
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• 2014

Purpose: It can deduce improvement plan that recognizes any risk factors in initial production and mass production by using FMEA and through this process, the appropriate criteria for defence items can be established. Methods: It proposes two methodology - Apply DT/OT data achieved from the beginning mass production stage based on FMECA data of the design stage, to risk management, and risk management plan that reflected line and field faliure data in case of is offered. Results: It proposes the risk management plan through Bayesian method and the risk identification that considered MTTF estimated value in case of initial production process. In case of mass production process, both risk identification by using fault occurrence frequency scores and Byaesian method, In case of the Initial production and mass production, it proposes use both two methods. Conclusion: A more realistic risk identification method can be applied, and by this method the quality improvement effect is expected.

• 한국가스학회지
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• 제18권2호
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• pp.1-9
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• 2014

석탄층 메탄가스 저류층의 개발을 위해서는 석탄층 특성에 부합하는 생산방법을 적용하는 것이 중요하지만 대부분의 개발현장에서는 경험적인 판단에 의존하여 생산방법을 선정하고 있어 결과에 대한 신뢰도가 떨어질 뿐만 아니라 복잡한 시뮬레이션 해석을 통해 최적 생산방법을 규명해야 하는 등의 많은 시간과 노력이 필요하다는 문제점이 있다. 이에 본 연구에서는 인공신경망을 활용하여 석탄층 메탄가스 최적 생산방법을 선정하기 위한 지능형 시스템을 개발하였다. 시스템 개발에 앞서 문헌 조사를 통해 석탄층 메탄가스 생산방법 선정 가이드라인을 분석하였고, 이를 활용하여 시추 방법과 유정완결법 선정 시스템, 수압파쇄공법 수행시 파쇄액 선정 시스템을 개발하였다. 개발된 생산방법 선정 시스템의 타당성 평가 결과, 높은 정확도를 나타냄으로써 본 연구에서 개발된 생산방법 선정 시스템은 향후 석탄층 메탄가스의 개발에 앞서 석탄층 특성에 부합하는 생산방법을 선정할 수 있는 효율적인 도구로 활용될 것으로 판단된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.68-69
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• 2014

Production of freeform concrete segments use various molds because of the unique shape of it unlike common concrete segments. As a result, the mold for freeform concrete segments cannot be reused. Therefor, cost overrun is occurred by needs of more time and manpower to produce the freeform concrete segments compared with common concrete segments. To prevent the cost overrun, a new production method for the freeform concrete segments is needed to develop and the requirements for it should be analyzed before. Therefor, the aim of this study is requirements analysis for production of freeform concrete segment. The requirements of production of freeform concrete segments and form for it is analyzed in this study. The result of this study would be used to suggest the new production method of freeform concrete segments.

• 한국막학회:학술대회논문집
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• 한국막학회 2005년도 추계 총회 및 학술발표회
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• pp.119-123
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• 2005

The thermochemical splitting of water has been proposed as a clean method for hydrogen production. The IS process is one of the thermochemical water splitting processes using iodine and sulfur as reaction agents. HI decomposition procedure to obtain hydrogen is one of the key operations in the process, because equilibrium conversion of HI is low (22% at $450^{\circ}C$). The silica membranes prepared by CVD. method were applied to the decomposition reaction of HI vapor. The permeation characteristics of hydrogen and nitrogen belong to the Knudsen flow pattern.

• 한국유기농업학회지
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• 제2권1호
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• pp.16-23
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• 1993

The traditional farming method has very long history in the process of agricultural development. The application of chemical fertilizers production became most popular to increase quantities of agricultural production. The United States of America is one of largest countries in the world. There are at present 50 States and farming conditions are very different from each individual States. There are increasing trend of agricultural production by applying chemical fertilizers as well as sprays during last 50 years(1940-90). The disadvantages of conventional farming method were to destroy nature and human life. There were some other kinds of disadvantages such as nitriated contamination in drinking water both for human being and animals. The alternative farming method is one of new farming method reducing and/of non-application of chemical fertilizers and sprays in agricultural production. There is less economic research on alternative farming system about $5.444 economic advatages in organic farms comparing commercial farms at the same area. There are advantage of higher unit price level in orgnic products, decreasing chemical costs as well as effect of crop combinations. It is certainly necessary to have more empirical research on economic and management of alternative farming method in the United States of America. However, if there is economic advantage in alternative farming methods, the future development possibility of alternative farming method can be very bright in vear future. There might be more advantages such as soil conservation, better quality of agricultural products, better health conditions of farmer's and consumer's as well as keeping healthy environment of rural and urban areas.