• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.157-163
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• 1997

This paper analyses a number of important areas relating to methane production in ruminants, consequent hazards and different methods of reducing this gas. Clearly methane not only affects on the environment but also on the economy of animal production. Several factors including feed, species, microbes, rumen environment, etc. are responsible for methane production in animals. Although methane production can be reduced by chemical manipulation, defaunation and strategic feeding, the latter was found to be effective because the method is easier to follow than the others. Furthermore, feeding technology could play an important role in reducing methane production particularly in developing countries because of its relative cost effectiveness. however, it needs to compare to what extent it could reduce methane production as well as cost of animal production. Therefore, research program needs to be concentrated on the appropriate feeding system to reduce methane production, consequently pollution and cost of production particularly in developing countries.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.477-482
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• 2021

Hydrogen production, hydrogen production cost, and utilization rate were calculated assuming four cases of hydrogen production system in combination of photovoltaic power generation (PV), water electrolysis system (WE), battery energy storage system (BESS), and power grid. In the case of using the PV and WE in direct connection, the smaller the capacity of the WE, the higher the capacity factor rate and the lower the hydrogen production cost. When PV and WE are directly connected, hydrogen production occurs intermittently according to time zones and seasons. In addition to the connection of PV and WE, if BESS and power grid connection are added, the capacity factor of WE can be 100%, and stable hydrogen production is possible. If BESS is additionally installed, hydrogen production cost increases due to increase in Capital Expenditures, and Operating Expenditure also increases slightly due to charging and discharging loss. Even in a hydrogen production system that connects PV and WE, linking with power grid is advantageous in terms of stable hydrogen production and improvement of capacity factor.

• 대한전기학회논문지
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• 제36권12호
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• pp.839-847
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• 1987

The probabilistic production cost is calculated by the Expected Incremental Generation Cost Curve(EIGC) method based on the multi-state and multi-block operating conditions. For this, A new algorithm for determining production cost by the EIGC and the generation availability curve (GAC) had been developed in order to realize better economic olad dispatch and better reliability for power system operation. The simpler method for determining the EIGC and the GAC is proposed for convenience and saving in computation time.

• 한국해양학회지
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• 제11권2호
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• pp.57-63
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• 1976

It was attempted to analyze the sensitivity of the oil prospect place named MARIA which placed inside Gulf of Alaska. For the analysis, P6031090, ECOANA( computer) which installed in the head office, Shell Oil Co was used and the data needed for computer programming were 1) Unit of Production data 2) Production Schedule 3) Total Gross Yearly Expenses and 4) Total Gross Capital and so on. The important data among the computer output 1) PVPAT (Present Value After Tax): $1,167,077,500 2) Payout After Tax: 3.14 Years (256,284,810 BBL Production) 3) Earning Power: 42% (After Tax) 4) PVPAT/BBL : $1.22 5) Capital/BBL : $2.00. On the other hand, the effect acted upon PVPAT with varying the Platform cost, Facility cost, Pipeline cost and Well cost was observed in comparion with the basic for range from 50% to 200%. Resultantly, the order was 1) Pipeline cost 2) Facility cost 3) Well cost 4) Platform cost for range form 100% to 200%. This project was completed by the contract with Shell Oil Co., and the geological data needed for this analysis were given by the head office and the development project started from Jan. 1976.

• Membrane and Water Treatment
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• 제11권5호
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• pp.363-374
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• 2020

Membrane distillation (MD) is a process used for water desalination. However, its commercialization is still hindered by its increased specific cost of production. In this work, several process configurations comprising Direct Contact and Permeate Gap distillation membrane units (PGMD/DCMD) were investigated to maximize the production rate and consequently reduce the specific water cost. The analysis was based on a cost model and an experimentally validated MD model. It was revealed that the best achievable water cost was approximately 5.1 $/㎥ with a production rate of 8000 ㎥/y. This cost can be further decreased to approximately 2 $/㎥ only if the heating and cooling energies are free of cost. Therefore, it is necessary to decrease the MD capital investment to produce pure water at economical prices.

• Nuclear Engineering and Technology
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• 제51권2호
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• pp.631-640
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• 2019

Thorium ($^{232}Th$) is four times more abundant than uranium in nature and has become a new important source of energy in the future. This is due to the ability of thorium to undergo the bombardment of neutron to produce uranium-233 ($^{233}U$). The aim of this study is to investigate the production cost of thorium oxide ($ThO_2$) resulted from the thorium extraction process. Four main parameters were studied which include raw material and chemical cost, total capital investment, direct cost and indirect cost. These parameters were justified to obtain the final production cost for the thorium extraction process. The result showed that the raw material costs were $63,126.00 - $104,120.77 (0.5 ton), $126,252.00 - $178,241.53 (1.0 ton), and $1,262,520.00 - $1,782,415.33 (10.0 tons). The total installed equipment and total cost investment were estimated to be approximately $11,542,984.10 and $13,274,431.715 respectively. Hence, the total costs for producing 1 kg $ThO_2$ were $6829.79 - $6911.78, $3540.95 - $3592.94, and $501.18 - $553.17 for 0.5, 1.0, and 10.0 tons respectively. The result concluded that with higher mass production, the cost of 1 kg $ThO_2$ would be reduced which in this scenario, the lowest production cost was $$501.18kg^{-1}$-$$553.17kg^{-1}$ for 10.0 tons of $ThO_2$ production.

• 미생물학회지
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• 제37권1호
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• pp.92-99
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• 2001

Pi1ot plant (200 l)에서의 유가식 배양에 의한 Ralstonia eutopha KHB 8862의 고농도 배 양을 통하여 Poly(3-hydroxybutyrate) (PHB)의 대량생산을 모색하였다. 그 결과 배양 80시간 후 168 g/l의 건체량과 건체량의 74%에 달하는 PHB를 생산할 수 있었으며, 이때의 고과당 시럽으로부터의 PHB 전환수율 및 PHB 생산성은 각각 0.27 (w/w) 및 1.6 $gl^{-1}$ $h^{-1}$ /이었다. 이를 토대로 본 연구에서는 미생물 발효에 의한 PHB 생산 cost 및 그 경제성을 분석하였다. 신규설비투자를 고려하지 않은 경우의 PHB의 생산 cost는 US$2.41/kg으로 산출된 반면에 신규 설비투자를 고려한 경우에는 US$3.15/kg으로 상승되었다. 탄소원의 PHB로의 전환수율과 발효 생산성 모두 PHB 생산비를 결정하는 중요요인이지만 전체 생산비의 37%를 차지하는 탄소원 원료비의 비중이 설비투자의 감가상각비 비중 (17%)에 비해 높기 때문에 생산성을 높이는 노력보다는 전환수율을 개선하는 것이 PHB 생산비용 절감의 핵심이 되는 것으로 나타났다. PHB chip으로의 제조시 PHB 생산 cost는 US$4.0/kg의 수준으로 현재로서는 범용 합성플라스틱에 비하여 경쟁력을 확보하지 못한다. 따라서 생산비 절감을 통한 범용수지로써 경쟁력 제고와 함께 바이오의약 분야 등의 고부가가치 영역에서의 새로운 용도 개발 등이 적극 요구된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.723-726
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• 2009

As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR are estimated in the necessary input data on a Korean specific basis. G4-ECONS developed by EMWG of GIF in 2008 was appropriately modified to calculate the cost for hydrogen production of SI process with VHTR as a thermal energy source rather than the LUEC. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if $CO_2$ capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of $CO_2$. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제7권1호
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• pp.49-55
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• 1994

This study was conducted to compare the of rearing native and cross-bred dairy cows and returns received from them. For this purpose, 144 cows of 132 household from 24 villages were randomly selected. of them, 96 were native cows and 48 were cross-bred cows. The study revealed that among the structure of cost components, labour charge occupied the major share in the total cost of milk production per litre. The total cost of rearing native and cross-bred cows was Tk. 14,155 and Tk. 19,854 per annum, respectively. The average net cost of milk production per litre was Tk. 14.12 for native cows and Tk. 0.52 and for cross-bred cows were Taka 3.40. The benefit-cost ratio of milk per litre was higher (1:1.33) in cross-bred cows than native ones (1:1.04). The study further showed that in comparing with bulk line cost, the price of milk per litre received by the farmers was higher in cross-bred cows than native cows. Therefore, the study recommends dairying with cross-bred cows as encouraging and viable commercial enterprise in Banfladesh.

• 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.