• 한국미생물·생명공학회지
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• 제23권3호
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• pp.275-281
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• 1995

From the plasmid pYA300 carring a CMCase of Rhizobium fredii USDA193 plasmid was subcloned into pBluescript II KS(+)/pBluescript II SK(+) vectors and designated pYA500 and pYA600, respectively. Escherchia coli cells transformed with pYA500 porduced the CMCase more than with pYA600. The orientation of the cloned fragment in pBluescript vector had the effect on gene expression in E. coli background. When the 1.7 kb CMCase gene fragment of R. fredii USDA193 was hybridized to EcoRI-digested total DNA from R. meliloti and R. fredii USDA 191 the unique bands hybridized respectively, indicating that some genetic diversity exists in the EcoRI restriction enzyme site for CMCase gene in Rhizobium strains. The optimum pH of enzyme activity was 7 and the optimum temperature of that was nearly 37$\circ$C. The cellulase-minus derivatives of pYA500 were constructed by Tn5 insertional mutation. Among 6000 transconjugants, two mutant plasmids (designated pYA500::Tn5a and pYA500::Tn5b) were detected from the cellulase- negative transconjugants. The product of CMCase gene was analyzed by one dimensional SDS- PAGE of the cell extracts. About 45 kDa protein was considered to be a product of CMCase gene.

• 한국관개배수논문집
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• 제18권1호
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• pp.4-17
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• 2011

The standard design methodology was suggested to construct wetland system for reducing non-point source pollution from Saemangeum reclaimed paddy land. To set for the design flow and concentrations, runoff and water quality survey were conducted during the irrigation period in 2008 at Gyehwa reclaimed paddy land located at near Saemangeum lake. It is rational that 1ha is the optimum constructed wetland size. To meet this size, the moderate drainage area of reclaimed paddy field was 50ha under the conditions that rainfall is 30mm, average runoff coefficient is 0.83, and runoff capture ratio is 0.6. At these condition, the runoff volume from 50ha was 10,520 $m^3/d$ including base flow during irrigation period. To select the optimum wetland system, several case studies were conducted by focusing on the tidal reclaimed land areas having wetland systems in Seokmun. Pond-Wetland system was selected as the standard model because of showing the highest reduction efficiency. Single variable regression equation were delivered to estimate effluent water concentrations from the designed wetland by using long-term monitoring data from the Seokmun experiment site. The effluent concentration from the designed wetland using these equation were showed moderately range.

• 한국재료학회지
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• 제33권4호
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• pp.151-158
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• 2023

In this study, a new type of composite material combined with carbonyl iron, a relatively strong ferromagnetic material, was prepared to overcome the current application limitations of Prussian blue, which is effective in removing radioactive cesium. The surface of the prepared composite was analyzed using SEM and XRD, and it was confirmed that nano-sized Prussian Blue was synthesized on the particle surface. In order to evaluate the cesium removal ability, 0.2 g of the composite prepared for raw cesium aquatic solution at a concentration of 5 ㎍ was added and reacted, resulting in a cesium removal rate of 99.5 %. The complex follows Langmuir's adsorption model and has a maximum adsorption amount (q_e) of 79.3 mg/g. The Central Composite Design (CCD) of the Response Surface Method (RSM) was used to derive the optimal application conditions of the prepared composite. The optimal application conditions achieved using Response optimization appeared at a stirring speed of pH 7, 17.6 RPM. The composite manufactured through this research is a material that overcomes the Prussian Blue limit in powder form and is considered to be excellent economically and environmentally when applied to a cesium removal site.

• 한국수자원학회논문집
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• 제40권12호
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• pp.995-1005
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• 2007

본 연구에서는 하천유역에서 소수력 개발 대상지점에서의 최적규모를 결정하는 방안을 제시하였다. 제시된 방안은 지형 및 수문자료의 구축, 발전소 모의운영, 경제성분석, 최적규모 결정과 같은 일련의 절차로 이루어진다. 최적규모 결정을 위해 경제성 평가지표 가운데 하나인 순현가를 이용하였고, 이를 통해 최적 설계유량과 시설물의 최적규모를 도출하였다. 초기비용의 산출을 위하여 기존 소수력발전소의 비용 자료를 검토하여 함수식을 개발하였고, 편익 산정시 현재 공시된 전력 기준단가를 이용하였다. 이러한 일련의 절차를 기존에 조사된 금강수계의 초강유역에 위치한 댐식, 수로식 소수력 지점 2개소에 적용하였으며, 최종적으로 설계유량과 시설물의 규모 변화에 따른 NPV 민감도를 확인하여 최적규모를 결정하였다. 본 연구에서 제시한 방법은 소수력 개발지점에서의 최적규모 및 경제성 여부를 사업추진 이전에 개략 추정하여 잠재수력 부존량을 확인함으로써 사업시행주체의 의사결정 지원 측면에서 활용도가 높을 것으로 기대된다.

• 지질공학
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• 제12권1호
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• pp.35-51
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• 2002

본 논문은 화산암지역에 건설되는 비축기지를 대상으로 지표지질조사, 지표단열조사, 시추조사, 수리시험 결과 등을 토대로 지하수유동 수치모델 해석을 통하여 저유공동의 기밀성 요건을 만족시킬 수 있는 수벽시스템을 설정하고, 이러한 시스템 하에서의 공동유입량과 인접시설과의 수리간섭 영향을 평가하였다. 수리지질 안정성 해석을 위한 접근방법 3차원 연속체 수치모델링과 더불어 이의결과를 비교 또는 보완하기 위한 단열망 모델링 해석방법을 병행하였다. 저유공동의 심도를 결정하고 투수성단열의 확률적인 상호연결성 정도를 계산한 결과와 연직 수리경사, 수벽공 효율성, 저유공동과 수벽시스템간 이격거리 등의 제반 요건을 만족시키는 수벽시스템을 계산하였다. 연속체 모델에 의한 저유공동으로의 누수량은 건설기간 중에는 130 ~ 140m$^3$/day, 운영 중에는 약 120m$^3$/day일 것으로 예측되었고, 단열망 모델에서는 80~175m$^3$/day의 범위인 것으로 계산되었다. 신규 시설의 건설로 인하여 기존 시설지구의 함양유역 감소가 불가피하고, 이로 인하여 지하수위 강하 및 유동량의 감소가 발생될 것으로 예상되므로, 보수적인 관점에서 기준 지하수위를 유지하기 위하여 인공적인 수압을 가해줄 수 있는 별도의 지상 혹은 지하의 수직 수벽시스템이 요구된다.

• 한국약용작물학회지
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• 제27권5호
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• pp.322-329
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• 2019

Background: Studies have suggested that the northern provinces of Gangwon-do are good sites for licorice (Glycyrrhiza uralensis Fisch.) cultivation in Korea, as they have similar temperatures to its original locations in northern China. However, poor growth and freezing injury are often reported in Korea. Therefore, it is necessary to reassess the domestic cultivation site of licorice. Methods and Results: To determine the optimum temperature for cultivating licorice, the growth, yield, and pharmacological characteristics of G. uralensis were assessed in a temperature gradient tunnel at Eumseong, Chungcheongbuk-do, Korea in 2017. Plant height increased until the temperature rose to $5.9^{\circ}C$ above the local external temperature. Yield (㎏/10a) increased by 46.9% when the growing temperature was $1.5^{\circ}C$ to $3.0^{\circ}C$ (T2) above the external temperature and by 72.6% when the growing temperature was $3.0^{\circ}C-4.5^{\circ}C$ (T3) above the external temperature. However, a difference of $4.5^{\circ}C-5.9^{\circ}C$ (T4) above the external temperature, decreased the yield by 9.8% compared to that at T2. The glycyrrhizin content of G. uralensis roots in each temperature band was 0.72%, 0.53%, 0.91%, and 0.84% (T1, T2, T3, T4), these differences appear to result form individual plant variation rather than growth temperature. Conclusions: Based on the results of this study, we estimate that the temperature-based optimum cultivation site for G. uralensis in Korea is the south central region, rather than the northern province of Gangwon-do. Improvement in growth and yield maybe observed if the plantations in the central Jecheon (Chungcheongbuk-do, Korea) are expanded into the south central region.

• 대한교통학회지
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• 제19권5호
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• pp.99-108
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• 2001

본 논문은 유류저장탱크의 최적입지를 선정하기 위한 GIS와 OR 통합적용기법을 제시하며, P-Median heuristic method와 MIP method가 모두 유류저장탱크의 최적입지 선정 문제에 적용될 수 있음을 실증하였다. 또한, 두 접근 방식에 의해 확인된 결과들은 동일하였다. P-Median heuristic method와 MIP method 를 풀이하는데 필요한 최단거리 매트릭스를 계산해내 기 위해 GIS기반 도로망과 해운네트워크를 구축·결합하였으며, 두 접근방법을 통해 우리나라의 최적 유류저장탱크의 입지를 선정한 결과 권역별로 군산항, 여수항, 부산항, 옥계항이 선정되었다. 위와 같이, 본 연구를 통해 CIS와 P-Median heuristic method, MIP method의 적용은 실증되었으며, 유사한 연구 또한 GIS와 OR의 통합적용을 통해 수행될 수 있을 것이다.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.62-69
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• 1999

In order to investigate the critical amino acid residues involved in the catalytic activities of $\beta$-cyclodextrin glucanotransferase ($\beta$-CGTase) excreted by Bacillus firmus var. alkalophilus, the amino acid residues in $\beta$-CGTase were modified by various site-specific amino acid modifying reagents. The cyclizing and amylolytic activities of $\beta$-CGTase were all seriously reduced after treatment with Woodward's reagent K (WRK) modifying aspartic/glutamic acid, N-bromosuccinimde (NBS) modifying tryptophan, and diethylpyrocarbonate (DEPC) modifying histidine residues. The roles of tryptophan and histidine residues in $\beta$-CGTase were further investigated by measuring the protection effect of various substrates during chemical modification, comparing protein mobility in native and affinity polyacrylamide gel electrophoresis containing soluble starch, and comparing the $K_m$ and $V_{max}$ values of native and modified enzymes. Tryptophan residues were identified as affecting substrate-binding ability rather than influencing catalytic activities. On the other hand, histidine residues influenced catalytic ability rather than substrate-binding ability, plus histidine modification had an effect on shifting the optimum pH and pH stability.

• Environmental Engineering Research
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• 제20권1호
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• pp.41-50
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• 2015

The cyanobacterium Anabaena doliolum Ind1 isolated from a coal mining site was tested for removal of cadmium at optimum pH 7.0 and temperature $25^{\circ}C$. The organism recorded high percentage of metal removal (92-69%) within seven days of exposure to 0.5-2.0 ppm cadmium. Biosorption onto the cell surface was the primary mode of metal removal. Fourier transform infrared spectroscopy (FTIR) established hydroxyl, amides, carboxyl, sulphate and carbonyl groups to be the major functional groups on the cell surface involved in cadmium binding. Cellular ultrastructure and a range of vital physiological processes (i.e., photosynthetic pigments, respiration, photosynthesis, heterocyst frequency and nitrogenase activity) remained unaffected upon 0.5 ppm treatment; higher concentrations of cadmium exerted visible adverse effects. Amongst the five photosynthetic pigments tested, phycocyanin was the most targeted pigment (inhibition was 15-89%). Both respiration and photosynthetic activities were inhibited by cadmium with more severe effect seen on respiration. 2.0 ppm cadmium exposure also had drastic negative effect on nitrogenase activity (87% decreased).

• 설비공학논문집
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• 제22권6호
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• pp.404-412
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• 2010

The purpose of this study is to accomplished an in-site evaluation method for existing building insulation status using Infra-red camera and to consider improvement performance to prevent condensation and draw the optimum insulation design method for building using simulation tool. The research contents of this study are to evaluate validity and suitability of building insulation defect survey using Infra-red camera for apartment housing with temperature and heat flow pattern analyze method. Based on this research, the three corners, weak part in condensation, were selected in apartment building and conducted simulation by three-dimensional steady state. From the results, it is required to strengthen insulation design, and it is founded that existing insulation system typically applied to most Korean apartment housings have serious insulation defect that insulation is disconnected by structural components at the joints of wall-slab and wall-wall in envelope. Thus, it is considerate to need a concrete technology improvement.