• 대한안전경영과학회지
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• 제5권4호
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• pp.169-185
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• 2003

Recently many researchers contributed to the understanding of Quality Control System, but the use of economics in the design of quality assurance system is limited in treatment of the relationship between the average incoming quality level (or average process quality level) of the incoming lot and the average outgoing quality level of this lot. In this study, a traditional concept of sampling inspection plan for the quality assurance system is extended to a consideration of economic aspects in total production system by representing and analyzing the effects between proceeding and succeeding production process including inspection process. This approach recognizes that the decision at each manufacturing process (or assembly process), is to be determined not only by the cost and the average outgoing quality level of that process, but also by the input parameters of the cost and the incoming quality to the succeeding process. By analyzing the effects of the average incoming and outgoing quality, manufacturing or assembly process quality level and sampling inspection plan on the production system, mathematical models and solution technique to minimize the total production cost for a general product manufacturing system with specified average outgoing quality limit are suggested.

• 전기학회논문지
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• 제58권4호
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• pp.700-707
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• 2009

The application of renewable energy in electric power systems is growing rapidly in order to make provision for the inequality of the climate, the dwindling supplies of coal, oil and natural gas and a further rise in oil prices. Solar cell generators(SCG) is one of the fastest growing renewable energy. This paper presents a methodology on probabilistic production cost simulation of a power system including SCGs. The generated power by SCGs is variable due to the random variation of solar radiation. In order to solve this problem, the SCGs is modeled as multi-state operational model in this paper. Probabilistic production cost of a power system can be calculated by proposed method considering SCGs with multi-state. The results show that the impacts of SCGs added to a power system can be analyzed in view point of production cost using the proposed method.

• Journal of Biosystems Engineering
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• 제28권3호
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• pp.199-208
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• 2003

In order to solve the shortage of roughage supply for dairy farm in Korea, winter cereal forage production after harvesting of rice in the fallow paddy field is studied. This study consist of two parts. One is the model development of the mechanized production which was already reported at the preview paper. This is the 2nd parts of the study. Also, the mechanized production model for cereal forage production in winter was reported in the previous study. In this paper, coverage area and mechanized wrap silge production cost are analyzed and compared to the other available feeds in Korea. Results of the research are summarized as follows; The coverage area for the winter cereal wrap silage production system in Korea is estimated to be 33.7 ha in case of working with a tractor and a set of implements. If two or three tractors are available, the coverage area is estimated to be 68.0 and 101.3 ha, respectively. The break even point (BEP) of the farming size is analyzed as 10 ha and its production(operating) cost is estimated to be 317 to 443 won/TDN-kg at the BEP point. The cost is lowered to 182 won/TDN-kg at 100ha-working, and is much lower compared with prices of imported feeds of 360∼600 won/TDN-kg. Therefore, winter cereal wrap silage model is judged to be feasible and desirable for a large scale production of forage in winter fallow paddy field.

• 수산경영론집
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• 제25권2호
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• pp.47-58
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• 1994

This paper tries to estimate cost and profit functions under Cobb - Douglas production technology in the coastal fishing, using duality theory of production technology and cost function. Therefore this paper estimates in advance the production functions with two input variables, the number of working persons per tonage(WEMP) and the number of fishing equipment per tonage(WEQU). Then this paper estimates profit function and implicit cost function using the estimated coefficients from production functions. The results of this study show that the annual average profit pertonage of long bag set fishing and trap fishing amount to 4.1 million won and 3.9 million won respectively.

• 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.

• Journal of Biosystems Engineering
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• 제21권4호
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• pp.474-481
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• 1996

Farm mechanization has been rapidly progressed in rice farming since the 1980's, in Korea. The mechanization has been achieved up to 95-97% in the year of 1995, except irrigation and drying process. However, rice production cost remains much more expensive than the cost of other rice farming countries. Since labor cost shares a major portion of the production costs, it is essential to save labor cost with automation and more sophisticated mechanization. However, it requires great capital investment which causes farm management worse. Therefore, the computer program was developed which can select machines to minimize the management and maintenance cost by analyzing available working days in different areas, machinery to purchase, farming size, total farming size in a village, number of machines and custom fee.

• 대한산업공학회지
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• 제41권3호
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• pp.243-252
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• 2015

This paper considers a supply chain consisting of a manufacturer under the cap-and-trade emissions regulation and a permit supplier. We study joint production quantity and investment in reducing permit production cost decisions for centralized and decentralized supply chains. We formulate two supply chain contracts with aims to coordinate the decentralized supply chain; wholesale price contract and cost-sharing contract. Under the cost-sharing contract, the manufacturer shares a part of the investment in reducing permit production cost and then is allowed to purchase emission permit at a lower price. We analytically find that the proposed cost-sharing contract with reasonable parameters can coordinate the supply chain whereas the wholesale price contract is not desirable to achieve the system-wide profit. Numerical example is followed to support the analysis.

• 품질경영학회지
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• 제25권4호
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• pp.57-70
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• 1997

Consider a production system where all manufactured products are screened through automatic inspection equipment. The products for which the measured value of quality characteristic is larger than the lower screening specification limit (SL) and smaller than the u, pp.r screeing specification limit(SU) are accepted. Those smaller than SL are reworked and those larger than SU are excluded from the process. Assuming that the quality characteristic is normally distributed with known variance, this paper suggests cost models which involve inspection cost, production cost, rework cost, exclusion cost and quality cost, and presents the methods of finding the optimal values of the screening specification limits and the process target. Numerical example is given to demonstrate the a, pp.icability of the cost models suggested in this paper.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.13-17
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• 1993

This study was conducted to determine the cost of production of semen and the rate of conception for artificial insemination in eight randomly selected districts of Bangladesh. A sample of 640 adopting farms were investigated. Results indicate that the cost of liquid semen per dose on full-cost and cash cast basis were Tk. 16.17 and Tk. 14.48, while the cost of locally produced exotic semen and imported semen were Tk. 31.25 and Tk. 110.00 respectively. The cost of liquid semen per insemination, per conception and per progeny on full-cost were Tk. 26.65, Tk. 50.64, and Tk. 56.27 respectively and on cash cost were Tk. 23.88, Tk. 45.37 and Tk. 50.41 respectively. The average cost of semen paid by the farmers was Tk. 14.00 and it was higher in urban areas than in rural areas. Out of the cost of A.I. centres, government had subsidized 92.16 percent and the rest 7.84 percent accrued as returns. About 40 percent of the produced semen was lost in the system which could not be used at all. The conception rate on first insemination was 53.6 percent. The rate increased to 73.2 percent upto the last insemination. The difference in conception rate between liquid semen (69.97%) and frozen semen (70.48%) was not statistically significant.

• 디지털산업정보학회논문지
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• 제17권2호
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• pp.37-45
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• 2021

In this study, we want to analyze the difference in cost structure for the LAN audience system, which emerged as an alternative to the existing audience system due to the influence of Covid-19, and to analyze the utilization of the LAN audience system. To this end, the incremental cost difference between the existing audience system and the LAN audience system in the production of the broadcast program was compared and analyzed through the broadcasting production case by the actually performed LAN audience system. According to the research, the existing audience system has a linear cost structure that increases with the number of audience participants, while the LAN audience system has a calculated cost structure that gradually increases with the range of audience participants. These findings indicate that the LAN-line audience system costs more than the audience system, but the total cost is lower than the audience system for a certain number of people or more. This is a supplement to the existing audience system, which could not attract more audiences due to the lack of production costs, suggesting that the online audience system plays a role in supplementing the open broadcasting production system.