• Proceedings of the Korea Technology Innovation Society Conference
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• 2002.05b
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• pp.221-228
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• 2002

In viewing R&D as a series of activities of problem solving in the course of technological learning in developing countries, national R&D is very likely to play an pivotal role in incubating and improving industrial technology and competitiveness, especially for S&T-intensive industries, such as nuclear fuel industry. To this end, the national R&D needs to be primarily designed to reinforce technological capabilities of the country including government research institutes (GRIs), industrial firms, etc., from the initial stage of absorption as well as at the innovation stage. Based on this strategic role, national R&D performed by GRIs should provide scientific knowledge and core technologies which are required for the absorbption of foreign technology and development of indigenous technological capabilities with which domestic technological efforts are made to successfully achieve not only technological imitation but also innovation in global sense.

• Journal of the Korean earth science society
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• v.26 no.1
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• pp.1-8
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• 2005

The purpose of this study is to identify the effect of Problem-Based Learning on Student's Creativity Ability in Middle School Science Class. The experimental group had Problem-Based Learning classes for six weeks and control group had traditional inquiry instruction for the same period. The results of this study presents that Problem-Based Learning is significantly effective for the improvement of creative skills test and creative tendencies. And PBL group student's had positive thinking for PBL. It's not easy to generalize these results because of many different variables. but the results suggests that teachers should make an effort to improve student's creativity applying Problem-Based Learning. And it's necessary to develop many kinds of problems and teacher's instruction method to enrich creativity in the process of Problem-Based Learning.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.367-367
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• 2022

토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. LID 기법은 자연적 기작(mechanisms)과 공정(process)을 이용하여 생태계의 물질순환(물순환 포함)과 에너지 흐름이 원활하도록 조성하는 기법으로, 불투수층면에서 발생되는 강우유출수를 관리 가능하다. LID 시설에는 전처리 시설을 두어 초기 고농도의 입자상 물질을 저감시키고, 강우유출수 저류공간을 통한 유출저감, 첨두유량 등을 저감시킨다. 이러한 전처리 시설에는 유기물질 및 영양소의 생물학적 제거를 위한 미생물 서식공간의 제공 등의 역할을 수행하기 위하여 다양한 여재를 적용하고 있다. 본 연구는 비점오염물질 유입이 LID 기법 전처리 시설 내 여재층의 물리·화학적 및 생물학적 환경을 평가하였다. 3개 시설 모두 100%의 불투수층에서 발생되는 강우유출수를 처리하는 LID 시설을 연구대상으로 선정하였으며, 각각의 전처리 시설에는 자갈, 우드칩, 쇄석 등이 적용되어 있다. 퇴적물의 경우 가장 상부에 존재하는 층으로 퇴적물의 오염물질 농도는 2~10.7배 이상 매우 높게 나타났다. 우드칩의 경우 다른 여재에 비해 높은 함수량과 유기물 함량을 보였으며 이는 우드칩의 수분을 보유하는 능력과 거친 표면공극에 오염물질이 부착되기 때문으로 나타났다. 또한, 같은 무기성 여재인 쇄석과 자갈의 경우 여재 크기의 차이를 보임에도 불구하고 미생물의 군집구성과 함수량의 차이를 보이는 것으로 평가되었다. 유기물의 함량이 낮은 강우유출수의 생물학적 처리능력을 향상시키기 위해서는 유기성 여재가 필요하며, 다공성 무기 멀칭재를 적용하고 하부의 토양은 적정 유기물을 배합하여 질산화 및 탈질화 유도가 가능하도록 설계가 필요한 것으로 분석되었다.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.258-259
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• 2006

국내외적으로 전력산업분야의 가장 큰 화두중 하나는 변전소 단위의 디지털화이며 특히 국외에서는 국제표준 변전자동화 시스템 연구와 제품개발 등에 인력을 집중 투자하고 있다. 국제적으로 지금까지 축적된 변전소 관련 제반 기술력 및 경험 둥을 바탕으로 전 세계적으로 단일화시키고 표준화된 변전소 자동화 규격인 IEC 61850 (Communication networks and systems in substations) 규격이 제정되었으며 따라서 향후 전력 관련 기업은 시스템 엔지니어링 기술, 전력기기 공급능력, 유지/보수/운영기술 등을 종합적으로 보유하고 자산 및 위험관리를 종합적으로 제공할 수 있어야만 세계시장에서 생존할 수 있다. 또한 전력기기를 수출하는 국내업체는 향후 IEC(International Electrotechnical Commission) 등 국제표준에 따른 전력설비를 개발하지 않으면 수출경쟁력을 잃게 될 것이다. 이러한 세계화 추세에 발맞추어 한국전력공사와 관련 업체들은 공동으로 2005년 10월부터 6년의 기간으로 "디지털 기술기반의 변전소 자동화 시스템 개발" 사업을 진행 중에 있으며 특히 한국전력공사는 변전자동화 시스템의 성능검증 및 실증시험 절차를 구축하기 위한 과제를 수행 중이다.

• Korean Journal of Construction Engineering and Management
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• v.23 no.1
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• pp.106-112
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• 2022

Additive manufacturing (AM, also known as 3D printing) technology gets attention for various effects in the construction industry. It reveals abilities of process automation, high traceability of resource management, construction period precision improvement, and worker safety. However, unlike the existing construction technology, the development of AM construction process causes trial errors and unpredictable accidents. In the present study, the construction AM process is designed for on-site construction, and it performs with empirical tests. Also, we analyzed the causes of qualitative experimental results.

• Analytical Science and Technology
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• v.12 no.5
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• pp.441-446
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• 1999

The changes of amino acids in the cotyledons of spring - and winter radishes were analysed during the abscisic acid (ABA). ABA plus cycloheximide (CH) and ABA plus polyamine (PA) treatment. The total contents of amino acids were increased in spring radishes, and decreased in winter radishes by ABA. The contents of hydrophilic amino acids, proline, glycine, serine and cysteine in spring radishes (expecially proline), and of cysteine, leucine and phenylalanine in winter radishes (expecially cysteine and leucine)were increased, CH treatment resulted in the accumulation of amino acids by the inhibition of new synthesized protein, which synthesized against ABA induced dehydration both of radishes. On the contrary, the contents of amino acids were decreased in spring radishes, and increased in winter radishes during PA treatment. These results indicated that the accumulated hydrophilic amino acids and new synthesized proteins induced the adaptation of dehydration against stress and the role of ABA in accelerating of stress adaptation was mediated by polyamines.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.221-228
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• 1974

산란직전의 남해산 참굴(Crassostrea gigas)을 산채로 구입하여 통상조건하에서 탈각하여 얻은 굴육질을 polyethylene laminated aluminium pouch (Al+PE : 0.03+0.03mm) 속에 밀봉하여 살균선량(0.2Mrad) 및 멸균선량(2.0Mrad)의 감마선으조 조사하고, 한편, 100ppm의 염소수에 굴육질을 2분간 침지한 후 탈수하여 같은 방법으로 포장하여 35일간의 빙장기간중 세균학적 및 화학적 변화를 대조 굴(조사치 않고 염소수 처리하지 않은)의 경우와 비교하였다. 굴육질의 시초의 총균수는 g당 700-800에 달했고, 0.2 Mrad의 감마선 조사는 빙장 10일째의 저장 기간중의 총 균수를 검측할 수 있는 선 이하로 감소시켰으며 2.0 Mrad 조사는 20일째까지 거의 무균상태를 가져왔다. 감마선 조사는 또한 세균활동을 표시하는 대사물질인 TMA와 TCA soluble nitrogen의 축적을 현저히 억제시켰으며 빙장 후기부터 번식하기 시작하여 총균수가 g당 100,000을 초과케 된 35일째까지도 대조굴의 동일한 총균수 시기에 비하여 이 대사물의 축적억제가 현저했음은 감마선 조사의 효과가 총균수의 양적인 감소뿐만 아니라 동시에 TMA를 생산하고 단백질을 분해할 능력이 있는 세균제거 내지는 번식의 억제라는 선택적인 양면을 가지고 있음을 보여 준다. 염소수 처리한 굴육질의 경우 총균수의 양적인 감소효과는 현저하지 않했는데도 불구하고 감마선 조사 경우처럼 세균대사물질 축적의 철저한 억제를 가져 왔음은 주목할만 하다. 굴육질의 glycogen 함량은 사후 저장 기간 중 쉽사리 감소되지 않했으며 PH 측정으로 본 생굴의 신선도와의 관련성은 희박하며 조사와 염소수 처리굴의 경우 더욱 그러했다.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.137-140
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• 1973

Two desert plant species were grown in solution culture with varying levels of boron. Both appeared to be very resistant to accumulation of large amounts of boron but F. dumosa accumulated moderately high amounts of it at levels of 10 or more ppm in the nutrient solution. Growth reduction was indicated for this species at 50 and 100 ppm boron in the nutrient solution. The high levels of boron resulted in decreased potassium levels in roots for this species. Growth seemed to increase for A. hymenelytra up to level of 20 ppm boron in the nutrient solution but boron content in leaves at this level was only 156ppm of dry weight. Higher levels did not further increase boron contents of leaves. The distribution of both of these species in the desert is probably related to their ability to accumulate small amounts of boron in the presence of large amounts of boron in the soil.

• Journal of Korea Water Resources Association
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• v.30 no.1
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• pp.83-93
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• 1997

The purpose of the study is to analyze the sensitivity of the parameters that affect the runoff and water quality in the studied drainage basins. SWMM model is applied to the four drainage basins located at Namgazwa and Sanbon in Seoul and Gray Haven and Kings Creek in the USA. first of all, the optimum values of the parameters which have least simulation error to the observed data, are detected by iteration procedure. These are used as the standard values which are compared against the procedure. These are used as the standard values which are compared against the varied parameter values. In order to catch the effectiveness of the parameters to the computing result, the parameters are changed step by setp, and the results are compared to the standard results in flowerate and quality of the sewer. The study indicates that the discharge is greatly affected by the types of runoff surface, i.e., impervious area remarkably affects the peak flow and runoff volume while the surface storage affects the runoff volume at mild sloped basins. In addition, the major parameters affecting the pollution concentrations and loadings are the contaminant accumulation coefficient per unit area per time and the continuous dry weather days. Furthermore, the factors that affect the water quality during the initial rainfall period are the rainfall intensity, transport capacity coefficient and its power coefficient. Consequently, in order to simulate the runoff-water quality, it is needed to evaluate previous data in the research performed for the studied basins. To accurately estimated from the tributary areas and the rational computation methods of the pollutants calculation should be introduced.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.5
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• pp.141-155
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• 2014

This study examines the effect of previous work experience on the long-lived venture firm called 'Good Quality startup'. The research explores entrepreneurs of 16 mobile application startups that were invested by the venture capital, 'K-ventures', through the resource-based view. The results show that all of entrepreneurs had previous experiences of their business domain. They accumulated human resources such as technology capabilities, knowledge of domain, know-how, networking through learning-by-doing. Entrepreneur's human resources are the key factors for opportunity recognition and realisation process; and it is also on the ground that venture capital determines investment. Venture capital provides financial resources, management support and strong network for venture firm. Technology resources, financial resources, know-how and networking are the core managerial resources to be a long-lived venture firm called 'Good Quality Startup'. This research is an exploratory case study based on previous experience and 'good quality entrepreneurship'. The empirical study hereafter is needed.