• 한국식품영양과학회지
• /
• 제40권3호
• /
• pp.450-457
• /
• 2011

본 연구에서는 콩 비린내가 감소되고 고소한 풍미가 증진된 볶은 콩에 다양한 볶은 곡류 분말을 혼합하여 Bacillus subtilis HA 고초균을 이용한 고체발효를 행하였다. 발효 원료의 수분함량 및 발효 시간에 따른 결과 볶은 콩 분말 대비 수분 1배 첨가된 초기 수분함량 52.6%에서 24시간 발효 후에 protease 활성이 42.6 unit/g으로 높았으며, 점질물 함량 역시 10.60%로 높았다. 발효 48시간째 tyrosine 함량과 protease 활성이 24시간째보다 높게 나타났으나, 발효취가 강하게 생성되어 발효 24시간이 가장 적합한 것으로 나타났다. 곡류 분말(보리, 현미) 종류에 따른 발효조건 최적화를 위해 실시한 결과 현미 첨가 시 점질물 함량이 유의적으로 증가되었고 특히 80% 첨가 시 24.55%로 대조구에 비해 약 2배 향상되었고, 보리는 60% 첨가 시 혈전용해효소 활성이 11.8 unit/g으로 대조구에 비해 약 2배 증진된 것을 확인하였다. 혈전용해효소 활성이 가장 우수했던 볶은 콩 대비 보리 60% 첨가 발효물에 청국장에서 분리한 균주 4가지를 접종하여 혈전용해효소 활성 및 비타민 $K_2$ 함량을 각각 알아 본 결과 B. subtilis HA가 11.8 unit/g, 2.36 ${\mu}g/g$으로 가장 효과적이었다.

• 오토저널
• /
• 제14권6호
• /
• pp.113-126
• /
• 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.

• 수산해양기술연구
• /
• 제50권4호
• /
• pp.467-475
• /
• 2014

This study was performed to estimate optimum fishing mortality (F) and the age at first capture ($t_c$) for small yellow croaker in Korean waters. We first estimated optimum F and $t_c$ using traditional yield-per-recruit (YPR) analysis, and the results were 0.8/year and 2.5 years old, respectively. However, the individual fish price per unit weight of small yellow croaker in Korea increases dramatically by size. Thus, we developed an alternative method, which is called as production value-per-recruit (PPR) analysis. We developed two types of the PPR analysis, that is, the discrete function and the continuous function method. We estimated optimum F and $t_c$ using the two types of the PPR analysis and compared the results. The optimum F and $t_c$ from the discrete function method, were 0.3/year and 5.0 years old, respectively, while those from the continuous function method were 0.5/year and 3.5 years old, respectively. These PPR estimates were much more conservative for the stock management than the traditional YPR analysis, which can prevent the fish stock from the economic overfishing. As a result, the PPR analysis could be more proper approach for stock assessment in the case that the individual fish price per unit weight increases dramatically by size like small yellow croaker in Korea.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권2호
• /
• pp.261-266
• /
• 2012

Fermented Chlorella vulgaris CBT$^{(R)}$ was evaluated for its effects on egg production, egg quality, liver lipids and intestinal microflora in laying hens. One hundred and eight Hy-line Brown layers (n = 108), 80 wk of age, were fed a basal diet supplemented with CBT$^{(R)}$ at the level of 0, 1,000 or 2,000 mg/kg, respectively for 42 d. Egg production was measured daily and egg quality was measured every two weeks. Five eggs from each replicate were collected randomly to determine egg quality. Egg production increased linearly with increasing levels of CBT$^{(R)}$ supplementation (p<0.05), although there was no significant effect of treatment on feed intake. Egg yolk color (p<0.001) and Haugh unit (p<0.01) improved linearly with increasing dietary CBT$^{(R)}$. Hepatic triacylglycerol level was linearly decreased with increasing dietary CBT$^{(R)}$ (p<0.05). The supplemental CBT$^{(R)}$ resulted in linear (p<0.001) and quadratic (p<0.01) response in population of cecal lactic acid bacteria. In conclusion, fermented Chlorella vulgaris supplemented to laying hen diets improved egg production, egg yolk color, Haugh unit and positively affected the contents of hepatic triacylglycerol and the profiles of cecal microflora.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권7호
• /
• pp.1043-1047
• /
• 2009

Three experiments were conducted to determine the conversion rate of formic and acetic acids into methane in the gastrointestinal tracts of geese. In experiment I, two sets of two 4-month-old male White Roman geese were allocated to one of two treatment groups. Each set of geese was inoculated either with formic acid or with phosphate buffer solution (PBS). After the acid or the PBS was inoculated into the esophagi of the geese, two birds from each treatment were placed in a respiratory chamber as a measurement unit for 4 h in order to determine methane production rate. In experiment II and III, 6- and 7-wk-old male White Roman goslings were used, respectively. Birds were allocated to receive either formic acid or PBS solution injected into the ceca in experiment II. Acetic acid or PBS solution injected into the cecum were used for experiment III. After either the acids or the PBS solution were injected into the cecum, two birds from each treatment were placed in a respiratory chamber as a measurement unit for 3 h; each treatment was repeated 3 times. The results indicated that formic acid inoculated into the oesophagi of geese was quickly converted into methane. Compared with the PBS-injected group, methane production increased by 5.02 times in the formic acid injected group (4.32 vs. 0.86 mg/kg BW/d; p<0.05). Acetic acid injected into the ceca did not increase methane production; conversely, it tended to decrease methane production. The present study suggests that formic acid may be converted to methane in the ceca, and that acetic acid may not be a precursor of methane in the ceca of geese.

• Mycobiology
• /
• 제43권4호
• /
• pp.467-474
• /
• 2015

Development of efficient substrate formulas to improve yield and shorten production time is one of the prerequisites for commercial cultivation of edible mushrooms. In this study, fifteen substrate formulas consisting of varying ratios of palm press fibre (PPF), mahogany sawdust (MS), Gmelina sawdust, wheat bran (WB), and fixed proportions of 1% calcium carbonate ($CaCO_3$) and 1% sucrose were assessed for efficient Lentinus squarrosulus production. Proximate compositions of mushrooms produced on the different substrate formulas were also analysed and compared. Substrate formulations containing 85% PPF, 13% WB, 1% $CaCO_3$, and 1% sucrose were found to produce the highest carpophore yield, biological efficiency and size (206.5 g/kg, 61.96%, and 7.26 g, respectively). Days to production (first harvest) tended to increase with an increase in the amount of WB in the substrate formulas, except for PPF based formulas. The addition of WB in amounts equivalent to 8~18% in substrate formulas containing 80~90% PPF resulted in a decrease in the time to first harvest by an average of 17.7 days compared to 80~90% MS with similar treatment. Nutritional content of mushrooms was affected by the different substrate formulas. Protein content was high for mushrooms produced on formulas containing PPF as the basal substrate. Thus, formulas comprising PPF, WB, $CaCO_3$, and sucrose at 85% : 13% : 1% : 1%) respectively could be explored as starter basal ingredients for efficient large scale production of L. squarrosulus.

• 멤브레인
• /
• 제4권1호
• /
• pp.1-8
• /
• 1994

There are growing needs to produce relatively high purity(99.0% or higher) oxygen at low cost. For small scale production, both pressure swing adsorption(PSA) and membrane process are competitive and less expensive or more convenient than well known cryogenic fractionation technology. A continuous membrane column(CMC) combined with a PSA oxygen generator can be employed to produce high purity oxygen continuously. The oxygen enriched gas generated by a PSA unit, with a concentration of 93~94%, is fed to the CMC that consism of three modules of poly(imide) hollow fibers. Several experiments were conducted by varying parameters, such as feed flow rate, transmembrane pressure drop, stage cut, and feed location in order to obtain a high oxygen concentration above 99.0%. A two-series unit mode was also employed with CMC operation to optimize the given membrane area.

• 한국유기농업학회지
• /
• 제17권1호
• /
• pp.1-17
• /
• 2009

The production of bio-energy crops is a major research project in the emphasizing the "low carbon green growth" strategy. For this, the possibility of the introduction of the new energy crops improve the agricultural income from fanning must be diagnosed. This study describes the level of agricultural income per unit area by cropping system based on the income of crops in the field. Especially, we have chosen the southern part attracting the attention in the possible area of the bio-energy crop production. This study consists of five chapters. Chapter I is the introduction. Chapter II is on the status of the southern part cropping system and the analysis of the economic value. Chapter III is on the economic value analysis introducing new bio-energy crops. Chapter IV is on the comparative analysis for the economic value of the croping system introducing new bio-energy crops. Chapter V is the conclusion.

• 한국식품영양학회지
• /
• 제6권3호
• /
• pp.169-177
• /
• 1993

The conversion of glutamate by glutamine synthetase Is the endergonic reaction that demands ATP as its energy source. In order to supply efficiently ATP that is demanded in the conversion of glutamate to glutamine, the ATP- generating system by acetate kinase partially purified from Escherichia coli K-12 was coupled with glutamine synthetase partially purified 5. coli K-12 Pgln6. The optinum conditions of the coupled reaction were investigated. As the result, the highest conversion of glutamate to glutamine was shown In the reaction mixture containing 100mM glutamate, 100mM NHtCl, 50M acetyl phosphate, 5mM ADP, 40M MgCl2, 300mM potassium phosphate buffer (pH 7.5), 5mM MnCl2, Under this condition, the most effective concentrations of enzyme were 70unit/ml glutamine synthetase and 99unit/ml acetate kinase. Under the optinum conditions, 98% of 100mM glutamate was converted to glutamine within 6 hours.

• 대한조선학회논문집
• /
• 제28권1호
• /
• pp.197-205
• /
• 1991

생산계획 최적화를 도모하기 위하여 선박조립공정을 구성하는 소 생산단위인 activity에 대한 수학적인 cost model을 수립하는 방법을 제시하였다. 이 cost model의 수립은 실제로 work study 방법을 이용하여 작업자수와 작업시간간의 관계식을 작성하고 Marginal costing 개념을 이용하여 해당기업의 연간 총 cost를 각 생산자원의 사용량에 분배하여 단위공수 및 단위시설 사용량에 대한 cost를 산출함으로서 이루어진다. 이 방법을 실제의 한 activity의 예에 적용하여 보고 일반적인 방법을 제시하였다.