• 한국자원식물학회지
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• 제12권3호
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• pp.204-208
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• 1999

백하수오 재배시 지주설치 비용 절감 및 생력 재배기술 확립 목적으로 자소 등 6작물을 지주작물로 공시하여 시험을 수행한 결과를 요약하면 다음과 같다. 1. 지주작물의 주당 분지수는 율무 7개, 자소 19개로 백하수오 덩굴유인에 유리한 조건으로 작용하여 자소 97%, 율무 100%의 덩굴유인율을 보였다. 2. 백하수오의 지상부 생육은 자소, 수수재배에서 네트지주재배보다 만장이 길었고, 주당 분지수는 네트지주재배 6개에 비하여 자소, 율무, 수수 재배에서 1~2개 많았다. m$^2$당 엽중은 네트지주 재배시 1,001g으로 가장 많았고, 지주작물재배에서는 자소, 율무, 수수에서 614~636g이었다. 3. 백하수오의 지하부 생육은 땅콩, 자소재배에서 근장이 길었고, 지근수는 네트지주재배 8개에 비하여 땅콩, 자소재배 4개, 율무재배에서 6개였다. 4. 10a당 백하수오의 생근수량은 네트지주재배에서 919kg으로 가장 높았고, 지주작물재배간에는 자소 717kg, 율무 656kg, 수수 652kg으로 네트지주재배에 비하여 22~29% 감수되었다. 5. 백하수오 수량은 감수하나 지주설치 비용 절감 및 지주작물의 수확으로, 자소, 율무, 수수를 이용한 백하수오 생력재배가 가능하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.129-138
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• 1993

The shortage of agricultural labour due to industrial growth has greatly induced the mechanization in Korean agriculture. However small and scattered land holdings have been the main constraints in the process of mechanization. This paper describes the interrelationships of farm land structure, machinery selection and machinery operation areas. The sandy silt loam irrigated paddy land having single crop a year was selected as a target areas for this study. Machine operation cost is greatly influenced by operation period, plot geometry and operation area. On the improved geometry plots, optimal machine size increases slowly with increase in operation area. Operable area increases due to increased effective machine capacity on better geometry plot. The difference between the effects of operation period and plot geometry is that in the former case, the cost reduction is caused by delay in increase of machine size, whereas in the latter case timeliness cost is reduced by increase ffective capacity. The effect of farmland consolidation is greater on small plots than that on big plots. Increasing wage rates have induced the adoption of more labor saving machinery. Bigger labor saving machines require enlargement of operation area and larger plots through improvement in farm land structure. Machine cost on poor plot geometry increases more rapidly than that on the good plot geometry and as operation area increases machine cost reduces significantly. It is concluded that the development of agricultural mechanization ion Korea will depend on the improvement in farm land structure and enlargement of operation area.

• 수산해양기술연구
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• 제49권3호
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• pp.291-300
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• 2013

The main purpose of this study is to analyse economic feasibility of low-carbon-oriented gear for anchovy boat seine. The results of benefit/cost analysis showed that use of the low-carbon fishing gear is economically feasible. Considering the fuel saving and relatively low $CO_2$ emission by reducing the resistance of gear, net present value by such type 1 gear improvement was estimated about -2,490 ~ -1,580 million won with the benefit-cost ratio 0.81~ 0.88. And net present value by such type 2 gear improvement was estimated about 6,540 ~ 7,780 million won with the benefit-cost ratio 1.79 ~ 1.94. Development of lowcarbon trawl gear would render significant contributions to reducing $CO_2$ emission in fishing operations and lead to reduce fishing costs due to fuel savings.

• Journal of Biosystems Engineering
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• 제31권5호
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• pp.430-435
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• 2006

Greenhouse horticulture in South Korea covered about 52,000 ha in 2005. Greenhouse area of about 12,000 ha has been heated during winter season with heating cost of $20{\sim}40%$ of total Production cost. Farmers engaged in greenhouse horticulture were changed into aged people. Therefore the laborsaving of working process and the saving of greenhouse heating cost should be accomplished simultaneously to increase income of greenhouse horticulture. The best method for saving of greenhouse heating cost is to install thermal tunnels into greenhouse. Then hot air heaters using fossil fuel should be changed into hot water heaters. In other words air heating using forced convection should be changed into natural convection system. In this research coil tube made of flexible PE pipe was designed as hot water heat exchanger and its heat exchanging characteristics were analyzed. This new heat exchanger has been adopted as a natural convection system for hot water heating of greenhouse horticulture.

• 대한영양사협회학술지
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• 제15권3호
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• pp.262-277
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• 2009

Fresh-cut foods have been widely used in the school foodservice industry due to their convenience and saving effects of labor and working hours. This study evaluated the effectiveness of using fresh-cut foods in school foodservice with respect to cost efficiency, customer satisfaction, employee satisfaction, and productivity. First, in terms of cost efficiency, the cost of the fresh-cut food per meal price significantly increased by 2.6% via the new production plan. Meanwhile, the costs of labor and food wastes significantly decreased by 3.0% and 0.3%, respectively, after implementing the new plan. Second, customer satisfaction towards foodservice significantly increased, from 2.94 points prior to the new plan to 3.45 points. Third, foodservice productivity such as of the number of meals per full-time equivalent employee increased by 5.7 meals, from 143.0 meals to 148.7 meals after intervention. The productivity index of work hours for producing a meal also increased and was reflected by a work time reduction of 0.77 minutes, specifically from 4.25 minutes to 3.48 minutes. The labor cost per meal also decreased by 29.9 won, from 331.91 won to 301.97 won, but there was no significant difference. Through these results, we identified that using pre-process foods in school foodservice has positive effects on labor saving, customer satisfaction, and employee work satisfaction.

• 콘크리트학회지
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• 제28권2호
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• pp.10-13
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• 2016

• 열처리공학회지
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• 제2권3호
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• pp.46-54
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• 1989

• 한국지반공학회지:지반
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• 제24권10호
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• pp.9-22
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• 2008

• 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.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.418-421
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• 2008

Because of steep rise of international energy cost in recent years high efficiency has been emphasized in energy policy. As far as injection molding machine is concerned, hybrid method using hydraulic and electric systems became the key to this energy saving. the energy saving and molding reproducibility of hybrid injection molding process were shown experimentally, power consumption of hybrid machine is 38% as compared with that of hydraulic machine. Furthermore, the molding reproducibility showed between two methods.