• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.525-528
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• 2001

본 연구는 메탄을 최대로 발생시킬 수 있는 최적조건을 탐색하는데 있다. 메탄을 많이 발생 시킬 수 있는 최적 온도와 pH를 결정한 다음, 여러 가지 탄소원에 대해 조사하였다. 온또는 $25^{\circ}C$. $30^{\circ}C$. $55^{\circ}C$에서, pH 는 pH 2, 4, 6, 8. 10 에서 , 그리고 탄소원은 methanol. formic acid. sodium acetate. succinic acid, glucose 에서 조사하였다. 결과적으로 볼 띠 1. 온도는 $55^{\circ}C$. pH 는 중성부근. 탄소원은 methanol 인 조건에서 가장 많은 메탄을 얻을 수 있었다.

• 한국환경보건학회지
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• 제12권1호
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• pp.39-45
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• 1986

This study was designed to observe the effect of temperature cycling on the production of aflatoxin by Aspergillus parasiticus R-716 in rice, barley, peanut and soybean. In those media, temperature cycling resulted in more total aflatoxin production by the strain of R-716 than constant incubation at $28{\circ}$C and natural condition did. Especially, high level of total aflatoxin ($1826{\mu}g$/30g) in rice medium at temperature cycling was produced. The intensity of yellow color of chloroform extracts correlated with the concentration of aflatoxin, and the ratio of aflatoxin $B_1$ to aflatoxin $B_2, G_1, G_2$ is lower at temperature cycling condition than at $28{\circ}$C.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.325-328
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• 2000

The effects of DO and pH on the mass production of pullulan with high-molecular weight from A. pullulans ATCC 42023 were evaluated. The maximum pullulan production yield (51%) was obtained at pH non control (initial pH 6.5) and DO control (above 50%) condition. The pullulan degrading enzyme was activated when the pH of broth reached lower than 5.0 and portion of low molecular weight pullulan was increased. The formation of a black pigment was observed at the initial stationary phase, 40hr of fermentation. Therefore, the fermentation should be carried out in pH non control and DO control condition and harvested before reaching stationary phase around 40h for the production of high molecular weight pullulan.

• Environmental Engineering Research
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• 제20권2호
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• pp.121-125
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• 2015

Biohydrogen production from food waste via dark fermentation was conducted by using mixed culture under various environmental conditions (initial pH, initial F/M ratio, initial ferrous iron ($Fe^{2+}$), and temperature condition) in batch reactor. The results revealed that the maximum hydrogen yield of $46.19mL\;H_2/g\;COD_{add}$ was achieved at the optimal conditions (initial pH 8.0, initial F/M ratio 4.0, initial iron concentration 100 mg $FeSO_4/L$ and thermophilic condition ($55{\pm}1^{\circ}C$)). Furthermore, major volatile fatty acid (VFA) productions of butyrate (765.66 mg/L) and acetate (324.69 mg/L) were detected and COD removal efficiency was detected at 66.00%. Therefore, these optimal conditions could be recommended to operate a system.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 추계학술발표논문집
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• pp.269-279
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• 2000

To keep enterprise's competitiveness on condition of the automatic manufacturing system such as FA, FMS and CIM, all the maintenance problems should be considered seriously in not only production and maintenance but also related Industrial safety. As we analyze in the surveys for the maintenance management of domestic enterprises and the causes of industrial accident, there will be necessity of drawing up countermeasures for prevention of industrial accidents and for ensuring expertise maintenance technologies. Based on these analyses, this study studied the safety information system, maintenance management information system, and the machinery condition diagnosis technique by using of the knowledge-based system under the internet environment. This web based knowledge-based diagnosis system can easily provide not only the knowledge of expert about deterioration phenomenon of industrial robot, but also the knowledge of relating safety and facility on everywhere, everytime. Therefore, when we use this system, it is expected to improve the efficiency of business processes in the production and safety.

• 산업경영시스템학회지
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• 제17권30호
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• pp.73-79
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• 1994

This paper propose Adaptive Maintenance as a new type of maintenance for machine failures which are unpredictable. A purpose of adpative maintenance is to decrease inconsistency. In order to pick up some of problems the traditional maintenance policy, We discussed Time Based Maintenance(TBM) and Condition Based Maintenance(CBM) with Bath-Tub Curve. By using Machine Condition Diagnosis Technique (CDT), Monitored condition maintenance deals with the dynamic decision making for diagnosis procedures at maintenance and caution level. Adaptive Maintenance is a powerful tool for Total Production Maintenance(TPM).

• 한국자원식물학회지
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• 제33권6호
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• pp.696-706
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• 2020

Cordyceps has been used in traditional Chinese medicine more than 2000 year ago. In this study, the new Cordyceps militaris was founded and isolated from O-dae mountain in Korea, and was identified its genetic characteristics. The newly isolation strain HB8 was most closet to Cordyceps militaris W141449 (99.82%), Cordyceps militaris JLCY-LI819 (99.82%) and Cordyceps militaris 4642 (99.81%), respectively. the genotypic result was show that train HB8 was belonging to the Cordyceps militaris genus, therefore, Cordycep militaris HB8 proposed with accession number MT835161. This study we find the optimal condition for production of cordycepin from Cordyceps militaris HB8 was 8 mg/g (200 g of pupa, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h) and the optimum condition for the production of adenosine was 2.6 mg/g (15 g of skim milk powder, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h).

• 상하수도학회지
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• 제21권4호
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• pp.467-475
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• 2007

This study was conducted to examine temperature effects on hydrogen production in anaerobic fermentation. 18 batch reactors were operated at mesophilic ($35^{\circ}C$) and thermophilic conditions ($55^{\circ}C$) to achieve maximum hydrogen production in anaerobic fermentation. Optimum hydrogen production conditions were also investigated at each temperature. Different trends were observed regarding pH effects on hydrogen production. This effect was not significant for mesophilic fermentation ($35^{\circ}C$). In this case, pH may not drop to interfere hydrogen production during the test. However, hydrogen production decreased without pH control for thermophilic condition ($55^{\circ}C$). Effects of heat treatment were observed for both fermentation process. Hydrogen production with heat treatment was higher than hydrogen production without heat treatment for both fermentation processes. The amount of produced hydrogen for each substrate concentration with temperature changes showed that more hydrogen was produced at $35^{\circ}C$ than at $55^{\circ}C$.

• Journal of Biosystems Engineering
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• 제26권6호
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• pp.495-502
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• 2001

Upright positioning of garlic cloves has been considered as an essential process for mechanical planting because positioning affects the quality and yield of garlic production. Due to the geometrical uniqueness and irregularity of garlic cloves in shape, the planting operation has been conducted by manual. Manual planting requires intensive labors and high production cost. The overall Boal of this research was to develop a garlic clove planter which maintains a garlic clone upright. Specific objective was investigating planting condition and physical properties of garlic clove. The results were summarized as fellows : Based on the survey results, a garlic clove planter should have a planting capacity of at least 140 cloves in a pyung (3.3m$^2$) with the row spacing of 140mm and hill spacing of 120mm for a productive cultivation.

• 대한설비공학회지:설비저널
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• 제17권2호
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• pp.131-139
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• 1988

The thermoacoustic oscillation induced in an air column with variable cross section area is investigated theoretically and experimentally. The onset condition of the oscillation is derived by equating the acoustic power production to the power dissipation. The power production at the heater is predicted by using the efficiency factor obtained by heat transfer analysis for a single wire in a uniform cross flow and considering the interference between heater wires. The power dissipation is estimated by measuring the attenuating coefficient from the pressure decay curve. The theoretical prediction to the onset condition of the oscillation is confirmed experimentally. The effect of the variation of the column cross section area on the onset condition is presented.