• KSBB Journal
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• 제30권6호
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• pp.307-312
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• 2015

Transgenic rice cells using RAmy3D promoter can provide high productivity, and the production of recombinant protein is induced by sugar starvation. In this system, productivity was reduced during the scale-up processes. To ensure the influences of shear stress and oxygen transfer rate, working volume and mixing performances were investigated under various agitation speeds and working volumes. In addition, inoculation methods including suspended cells and filtered cells were compared. Working volumes and shaking speeds were 300, 450 mL and 80, 120 rpm, respectively. Hydrodynamic environment of each condition was measured numerically like mixing time and $k_La$. Good mixing performance and high shear stress were measured at high agitation speed and low volume. The highest level of hCTLA4Ig was 30.7 mg/L at 120 rpm, 300 mL. When conditioned medium was used for inoculation, increased cell growth was noticed during the day 0~4 and decreased slower than filtered cells. Compared with filtered cells, the maximum hCTLA4Ig level reached 37.8 mg/L at 120 rpm, 300 mL and lower protease activity level was observed. In conclusion mixing performance is critical factor for productivity and conditioned medium can have a positive effect on damaged cells caused by hydrodynamic shear stress.

• 한국초지조사료학회지
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• 제15권1호
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• pp.30-36
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• 1995

Pasture composed of about 30% botanical composition of white clover (Trijolium repem L.) is desirable in its productivity and quality. To get information on maintaining its productivity in the pasture, the experiment was canied out to determine the effect of infrequent, frequent defoliation or their alternation on change of its harvest yield and growth. Individual plants of Regal, Louisiana S-1, Grasslands Huia and Aberystwyth S184 were grown in 22cm plastic pot containing a 2 : 1 : 1 soil : sand : Peat moss mixture for 27 days after transplanting 50day seedlings raised on 3cm pots, and then all their fully expanded leaves are removed. Defoliation treatments were forced every 1 (CC, frequent), 4 week (RR, infrequent) or their alternations (CR, RC) after 8 weeks from the removal. To analyze the treatment effects, plants were sampled on 0 (the removal day), 4, 8, 12 and 16 weeks after the removal and seperated to leaves, petioles, stolons and roots. Each harvest yield of infrequent defoliation (RR) was higher than that of frequent defoliation (CC). Their alternations (RC, CR), however, forced fluctuation of the yield according to defoliation interval. Fraction weights from their altemations showed intermediate ones of infrequent and Frequent defoliation whose weights did the similar result to their harvest yields. Fraction and total dry weights per plant, shoot/root ratio were changed by relative span of defoliation interval, which resulted from the weights of leaves and petioles, removed parts. Root and total dry weight per plant of Regal were greater than the other cultivm in infrequent defoliation interval regardless of continuous or alternations. Productivity of white clover in pasture, therefore, can be controlled by alternation of infrequent and frequent defoliation or reverse.

• 한국환경과학회지
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• 제27권8호
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• pp.641-650
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• 2018

Paddy-upland rotation system is one of the important cropping system for improving soil quality and crop productivity. we conducted to investigate the effect of paddy-upland rotation system on soil properties and crop productivity in reclaimed tidal land. The paddy-upland rotation could be effective to conserve soil water contents and prevent from salt damage when cultivating upland crops. The first two years of maize cultivation after rice cultivation could be effective to secure stable production. However, in case of soybean crop, the rotation effect might be lower than that of maize. In the first year, the yield of soybean was 214 kg/10a. In the second and third year, the yields of soybean decreased consecutively to 152, 123 kg/10a respectively. In this paper, it would be suggested that maize be cultivated for up to two years and soybean be cultivated for one year after rice crop grown in reclaimed tidal land. This study could be provide basic data of the physico-chemical properties applicable to paddy-upland rotation system at reclaimed tidal lands.

• 한국미생물·생명공학회지
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• 제30권2호
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• pp.123-128
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• 2002

토양으로 부터 xylan 분해능이 우수한 Bacillus sp. AMX-4를 분리하고 동정하였는데 분리균의 화학조성은 B. subtilis와 유사성을 보였다. 분리균이 생산하는 xylanase는 50℃와 pH 6에서 최대활성을 보였다. 배지의 부가 탄소원을 첨가하여 Bacillus sp. AMX-4을 배양한 결과 xylose를 첨가한 배지에서 xylanase 생산성이 가장 증가하는 것으로 나타났으며, xylose를 1.5％(w/v)가 되도록 첨가하였을 때 배양상등액의 xylanase 활성이 29.2 U/ml로 약 16배 정도 생산성이 증가하였다. Xylose를 첨가한 배지와 첨가하지 않은 배지에서 Bacillus sp. AMX-4를 배양하여 균의 성장과 효소 생산성을 비교한 결과 xylose를 첨가한 배지에서 효소 생산뿐만 아니라 분리균의 최대 성장정도도 증가한 것으로 보아 xylose는 균의 성장과 xylanase 생합성을 동시에 유도하는 것으로 판단된다. 또한 xylanase는 균의 성장과 연계되어 생산되는 것으로 확인되었다.

• Journal of Information Technology Applications and Management
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• 제9권3호
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• pp.113-127
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• 2002

The effort for software process improvement is lately surging its interest though it does not satisfy both developer and receiver In terms of low productivity, quality, delay and increasing cost. According to current research, software process improvement contributes to improvement of productivity, its Duality, reduction of development time and cost, and the prediction of the time limit for delivery, which means software process improvement affects competitive advantage among developers. The latest research is whether the investment for information technology substantially had effect on improvement of productivity. That is, software process improvement and maturity of software industries has influence upon economic efficiency and as a result, it plays an important role in whole industries. This research is that how does software process improvement using CMM (Capability Maturity Model) and SPICE (Software Process Improvement and Capability dEtermination) have a effect on factors of software engineering, and how does it have influence upon competitive advantage among SI firms. For this research, reusability, customizability, participation, and review & inspection are set to independent variable and process flexibility and process predictability are set to mediate Variable. Finally, competitive advantage among SI firms Is set to dependent variable. The targets for survey are laborers who work for SI firms. The result of this research is as follows: 1 ) Reusability, Customizability and participation is not rejected but review and Inspection is rejected in process flexibility which has significant level 0.05. 2) Reusability, Customizability and participation is not rejected but review and inspection Is rejected in process predictability which has significant level 0.05. 3) Process flexibility is not rejected and process predictability Is rejected in the competitive advantage of 51 industries which has significant level 0.05

• ALGAE
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• 제31권3호
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• pp.257-266
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• 2016

Nitrogen is one of the most critical nutrients affecting cell growth and biochemical composition of microalgae, ultimately determining the lipid or carbohydrate productivity for biofuels. In order to investigate the effect of nitrogen sources on the cell growth and biochemical composition of the marine microalga Tetraselmis sp., nine different N sources, including NaNO₃, KNO₃, NH₄NO₃, NH₄HCO₃, NH₄Cl, CH₃COONH₄, urea, glycine, and yeast extract were compared at the given concentration of 8.82 mM. Higher biomass concentration was achieved under organic nitrogen sources, such as yeast extract (2.23 g L⁻¹) and glycine (1.62 g L⁻¹), compared to nitrate- (1.45 g L⁻¹) or ammonium-N (0.98 g L⁻¹). All ammonium sources showed an inhibition of cell growth, but accumulated higher lipids, showing a maximum content of 28.3% in ammonium bicarbonate. When Tetraselmis sp. was cultivated using yeast extract, the highest lipid productivity of 36.0 mg L⁻¹ d⁻¹ was achieved, followed by glycine 21.5 mg L⁻¹ d⁻¹ and nitrate 19.9 mg L⁻¹ d⁻¹. Ammonium bicarbonate resulted in the lowest lipid productivity of 14.4 mg L⁻¹ d⁻¹. The major fatty acids in Tetraselmis sp. were palmitic, oleic, linoleic and linolenic acids, regardless of the nutritional compositions, indicating the suitability of this species for biodiesel production.

• Ocean and Polar Research
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• 제34권2호
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• pp.239-251
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• 2012

The food web dynamics in a coastal ecosystem of Korea were predicted with Ecosim, a trophic flow model, under various scenarios of primary productivity due to ocean warming and ocean acidification. Changes in primary productivity were obtained from an earth system model 2.1 under A1B scenario of IPCC $CO_2$ emission and replaced for forcing functions on the phytoplankton group during the period between 2020 and 2100. Impacts of ocean acidification on species were represented in the model for gastropoda, bivalvia, echinodermata, crustacean and cephalopoda groups with effect sizes of conservative, medium and large. The model results show that the total biomass of invertebrate and fish groups decreases 5%, 11~28% and 14~27%, respectively, depending on primary productivity, ocean acidification and combined effects. In particular, the blenny group shows zero biomass at 2080. The zooplankton group shows a sudden increase at the same time, and finally reaches twice the baseline at 2100. On the other hand, the ecosystem attributes of the mean trophic level of the ecosystem, Shannon's H and Kempton's Q indexes show a similar reduction pattern to biomass change, indicating that total biomass, biodiversity and evenness shrink dynamically by impacts of climate change. It is expected from the model results that, after obtaining more information on climate change impacts on the species level, this study will be helpful for further investigation of the food web dynamics in the open seas around Korea.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.74-79
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• 2006

정부정책 수립자들은 일반적으로 정책들의 종합적이고 전체적인 영향을 제대로 고려하지 못하고 개개의 정책목표만을 달성하려는 경향이 있다. 또한 전형적인 정책결정 관행은 산업참여자들의 다양한 요구와 그들의 공공정책에 대한 반응을 제대로 고려하지 못하고 있다. 본 연구는 이 쟁점을 검토하기 위해 시뮬레이션 모델 베이스 접근법의 하나인 시스템 다이내믹스 모델을 이용하여 공공정책의 효과성윤 체계적으로 평가한 수 있는 방법을 제안하였으며, 건설 생산성을 강화하기 위한 싱가포르 정부의 정책들을 사례로 적용하였다. 이러한 시뮬레이션 모델을 이용하여 싱가포르 정부의 정책을 분석하였다. 모델 구조와 시뮬레이션 결과로부터 얻은 정책의 함축적 의미와 인과관계들을 토대로 정부 정책 수립을 보다 효과적으로 만들 수 있는 제안과 고려사항들을 제시하였다. 이러한 연구결과를 바탕으로, 시뮬레이션 모델 기반의 접근 방법이 건설정책 수립과 분석에 유용하게 활용될 수 있음을 파악하였다.

• Plant Resources
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• 제6권2호
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• pp.120-128
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• 2003

The objectives of this study, an analysis of the variation for leaf and fruit characteristics among the selected ten populations of Sorbus commixta Hedl. could be used for the conservation of gene resources and could provide information to superior trees selection. The results obtained from this study can be summarized as follows; Approximately, the Mt. Sungin population at Ulleung island showed larger values in overall characteristics and populations. On the other hand, Mt. Halla population at Jeju island showed the smaller values of the overall characteristics and populations. ANOV A tests showed that there were statistically significant differences in all leaf characteristics among the populations as well as individual trees within populations. But, for fruit characteristics, differences were statistically significant only among the populations. Cluster analysis using single linkage method based on leaf and fruit characteristics showed that ten selected populations of S. commixta in Korea could be clustered into three groups. Group I is Mt. Sungin at Ulleung island, Group II is Mt. Halla at Jeju island, and Group III comprises Osan, Mt. Kaji, Mt. Duckyoo, Mt. Balwang, Mt. Sobaek, Mt. O-dae, Mt. Jiri, and Mt. Taebaek. The selection level based on major agronomic traits, which are the Number of Fruit per Fruiting Lateral(NFL) over 50, and Fruit Length(FL) and Width(FW) over 10 mm, and Weight of 100 Fruit(WFI00) over 66 g, was applied on 100 sample trees, and five trees were selected. The selection effects from selected trees in NFL, FL, FW, and WF100 were evaluated as 132%, 151 %, 142%, and 264% compared to the mean of those 100 sample trees, respectively. Especially, Ulleung 2 showed excellent values that NFL and WFI00 were 95, and 69 g, respectively, suggesting a promising new cultivar for larger fruit and high productivity.

• 청정기술
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• 제24권3호
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• pp.255-266
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• 2018

본 논문에서는 대형 국가산업단지의 생산량이 지역 유해물질의 발생량에 미치는 영향을 단지규모, 산업 특성을 기반으로 분석하였다. 서울의 경우에는 제조업 기반보다는 지식기반산업 중심으로 서울 전체의 대기환경에 악영향을 미치는 유해물질의 발생비중은 타 지역 산업단지에 비하여 상당히 적었다. 반면에 기계, 금속, 전기, 전자 등 제조업 기반의 타 국가산업단지는 업종별 특성과 유통물류 및 지역적 특성이 복합적으로 영향을 미치는 것으로 조사되었다. 전체적으로는 대형 국가산업단지의 생산성 증대가 지역전체의 유해물질의 증가에 비례하지는 않는 것으로 조사되었다. 또한, 중화학공업 기반인 경북의 경우에는 업종의 특성으로 인하여 타 지역과 달리 유해물질 종류의 비중이 다른 지역과 다르게 나타나는 것으로 조사되었다.