• 한국초지조사료학회지
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• 제13권4호
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• pp.278-285
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• 1993

본 시험은 요소의 시비수준을 0, 100, 200 kg/ha로 하고 가축분뇨의 시용량을 질소함량을 기준으로 0. 40, 80, 160 kg/ha로 했을 때 영년 Orchardgrass 초지의 생산성과 토양중 NO$_3$-N 함량에 미치는 영향에 대하여 연구한 결과는 다음과 같다. 1 초지의 생산성은 요소 N 시용량이 100 kg/ha 수준까지에서는 분뇨 N의 시용량의 증가에 따라 유의적인 증가를 보여 주었으나 요소 N의 시용량이 200 kg/ha 수준에서의 분뇨 160 kg/ha은 오히려 목초의 생산성을 감소시켰다. 2. 분뇨 N의 평균적인 계절 생산성은 요소 N의 시용량의 증가에 따라 1번초와 3번초의 수량은 감소되었고 2번초의 수량은 증가되었다. 3. 요소 N 및 분뇨 N의 증가는 조단백질의 함량을 증가시켰으나 분뇨 N 보다는 요소 N의 시용효과가 더 높았다. 4. N의 총 생산량은 요소 N과 분뇨 N 시용 모두 지속적인 증가를 보였으나 N의 순 생산량은 이와 반대로 N 시용량 증가에 따라 감소되어 200 kg N/ha의 요소와 160 kg/ha의 분뇨 N의 시용시에는 오히려 -63.1 kg/ha의 순 생산성을 나타내었다. 5. 요소 N과 분뇨 N의 시용에 따라 1년차 Orchardgrass 초지 토양중의 NO$_3$-N 함량은 N의 종류나 시용량간에도 서로간에 차이를 나타내지 않았으나 계절적으로는 하계, 추계, 동계의 순으로 증가하였으며, 동계에서는 34.9 ppm으로 높은 함량을 나타내었다.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.1-7
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• 1996

The net primary productivity and potential natural vegetation in the Korean peninsula in the 21st century were estimated by the Miami model and thermal climate, respectively, based on 148 meteorological data sets. In the 21st century, the distribution range of the net primary produtivity in the Korean peninsula was estimated as 1,050 g $DM{\cdot}m^{-2}{\cdot}yr^{-1}~2,050g\;DM\cdot m^-2\cdot yr^{-1}.\; These\; values\; increased\; by\; 200g\; DM\cdot m^{-2}\cdot yr^{-1}\;on\;northern\;part\;and\;400g\; DM\cdot m^{-2}\cdot yr^{-1}$ on southern part compared with that of the present century. The potential natural vegetation in the Korean peninsula in the 21st century will change into the followings:coniferous forest on Mt. Paektu area, deciduous broadleaf forest on northern part, and evergreen broadleaf forset on southern part.

• 약학회지
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• 제44권1호
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• pp.60-65
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• 2000

The yeast extract, coconut water, safflower seed oil, arachidonic acid, linolenic acid, jasmonic acid and methyl jasmonate were added to Gamborg's B$_{5}$ medium. The changes on productivity of baccatin III were estimated every 30 minutes and the results were compared using the selected high yielding cell culture system of Taxus cuspidata. In most cases, the peaks of baccatin III productivity occured at 90~120 min after addition of elicitors. Among the compound elicitors, safflower seed oil showed the highest productivity of baccatin III. Also arachidonic acid and linolenic acid increased the baccatin III production.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.44-49
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• 1999

Cellulase production by fed-batch cultivation of Trichoderma reesei Rut C30 with various initial concentrations of Solka Floc in 1 % wheat bran-containing medium was investigated. The cellulase activity and productivity increased with initial Solka Floc concentration up to 5%. When a total Solka Floc concentration of 90 g/l was used for cellulase production, CMC (carboxymethyl cellulose) and FP (filter paper) activities, productivity, and yield were 359.7 U/ml, 30.61 U/ml, 161 FPU $L^{-1}$ $h^{-1}$, and 340 FPU $g^{-1}$, respectively. It was important to maintain a high cell concentration during cellulase production to obtain high cellulase activity and productivity. Cellulase powder was prepared by ammonium sulfate precipitation: FP activity was 396.7 U/g and CMC activity was 6481 U/g.

• 미생물학회지
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• 제17권3호
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• pp.152-159
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• 1979

Using Micromonospora strain, gentamicin was produced by fermentation. The increase in gentamicin productivity was studied by strain improvement and systematic optimization of fermentation process variables. The productivity of parent strain of M.purpurea (ATCC15835) was improved by selection of superior mutant after U.V. irradiation and induction of genetamicin resistance. Potato starch and soy bean meal were the best carbon and nitrogen sources for gentamicin fermentation, respectively. The optimum stimulating concentration of Co ion for gentamicin production was 0.006g $CoCl_2$ per liter of broth. Oxygen ws found to be an important factor for gentamicin yield. The optimum pH for the cell growth and gentamicin production were 7.2 and 6.8 respectively. By controlling the pH, oxygen, and other conditions found in this study at the optimal conditions for cell growth and gentamicin production, the total productivity of gentamicin was increased significantly.

• 한국정밀공학회지
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• 제19권3호
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• pp.73-79
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• 2002

This paper presents the experimental results to verify the environmental consciousness with economic balances due to cutting fluid behaviors, effectiveness in machining process. Even though cutting fluid improves the Productivity through the cooling, lubricating effects, its environmental impact is also increased according to the cutting fluid usage. The primary mechanism considered in this study is the spin-off motion of fluids away from rotating workpiece. In this study some parameters arc adopted to analyze the productivity(tool wear), environmental impact(mist diffusion rate). The results present talc criteria for the resonable cutting fluid usage quantitative1y to develop the environmentally conscious machining process.

• 소성∙가공
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• 제14권3호
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• pp.200-206
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• 2005

In general, a lot of small electrode is needed for making precision injection molds, such as cell phone mold and precision connector mold, because of the limitations of NC milling process. Those small electrodes usually have very simple shapes and the actual cutting time is so short, but many NC programs and set-up process, a very complicated and time consuming Job, are needed for each electrode. This paper deals the method for increasing the productivity of machining electrodes. In this work, the process standardization of machining electrode was done and special jig fer machining small electrodes was developed. Automatic tool path optimization software was also developed to minimize tool changing time. In addition, in-line cutting tool measuring system was adopted. The productivity of machining for small electrode has been increased up to $100\%$.

• 대한안전경영과학회지
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• 제12권3호
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• pp.215-221
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• 2010

Many researches and projects are actively implemented in the academic world and industrial world in order to increase the productivity through changing utility layout. Effective layout makes the flow of parts and products go on wheels and helps labor forces and utilities to be used efficiently. In this study, we looked at effect on utility layout change through a case of a company making a fuel tank of vehicle in Korea. Due to the layout improvement, this company could have flowshop system on welding line, so the stock in line was decreased, checking the number of stock became easier than before and it was possible to evaluate exact cycle time per unit. Through not only confirming qualitative effect, but also checking quantitative effect such as UPH(Unit per Hour), we obtained the conclusion that the layout improvement increased the productivity.

• Design & Manufacturing
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• 제10권2호
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• pp.39-43
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• 2016

Most of automobile parts manufactured through sheet metal forming are mass-produced by using press mold. In recent years, automation and speeding up of press lines have been expanding to maximize product productivity using a press die. The proportion of the moving time in the press line is high, and therefore requires high-speed and automated equipment for the moving process. In this paper, to provide the double-moving system can be the moving time reduction and increased productivity. Developed transport system consists of the material supply, the material feeding device and the PLC controller and the devices are positioned between each of the pressing process. In this paper, the double-moving system including developed units using a multi-axial single-acting through this reduced the C/T(cycle time) and improved the productivity.

• 한국정밀공학회지
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• 제18권1호
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• pp.117-122
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• 2001

Many kinds of channels are used in industrial equipment and production machinery. Although mechanical saw has been used to cut many sorts of channels, there is cost rise problem because of low productivity. Shearing of channel has a special place because it helps to cut expected shape and size easily. A channel cutting die set which can be mounted and used on a hydraulic press is developed to improve the productivity of channel cutting process. Mode for the channel cutting is divided into single cut and double cut method. This study use double cut method, and the developed channel cutting die set is composed of upper and lower die set. Shearing time can be reduced from 40 minutes to 20 seconds using the developed channel cutting die set. The productivity of channel cutting process can be increased with shearing time reduction as well as cost reduction.