• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.341-348
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• 2016

This study aimed to develop a microbial process for producing aminolevulinic acid (ALA) using crude glycerol. In the culture of ALA-producing cells (Escherichia coli/pH-hemA) in a medium containing crude glycerol, the cell density and production were 1.8-fold and 1.2-fold lower than those obtained from pure glycerol, respectively. However, the cell growth and production were improved by supplementing the medium with trehalose (30 or 100 g/l). Engineered cells (E. coli/pH-hemA/pS-otsBA) were constructed to express otsBA and their culture performance was compared with that of control cells (E. coli/pH-hemA/ pSTV28). The effects of isopropyl β-D-1-thiogalactopyranoside (IPTG) concentration and the time of induction were examined to improve the cell growth and ALA production in engineered cells cultured using crude glycerol. When 0.6 mM of IPTG was added at the beginning of the exponential growth phase, the ALA produced by cells was 2,121 mg/l, which was comparable to that from pure glycerol. The results demonstrate that otsBA expression endowed cells with the capacity to tolerate the toxicity of crude glycerol for direct use.

• Journal of the Korea Concrete Institute
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• v.19 no.3
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• pp.293-300
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• 2007

In Korea, the seismic design regulations was established since 1988 about regularity scale of structures. However, It was not established about seismic performance and evaluation method as the most existing buildings was constructed before Earthquake-Resistant Design(1988). In this study, for model structures which are 4 units of non-seismic designed apartment and 3 units of seismic designed in Korea performed seismic performance evaluation by suggested KISTC (2004). And the result compare to evaluate Capacity Spectrum Method by using MIDAS Gen and SDS. As a result, we observed that suggested KISTC's method have overestimated for shear stress and drift index. The purpose of this study provides most conformity seismic performance evaluation process and the appropriate method of calculating the seismic performance index in Korea.

• Geophysics and Geophysical Exploration
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• v.4 no.4
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• pp.133-144
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• 2001

An effective seismic reflection technique for mapping the cavities and bedrock surface in carbonate rocks is described. The high resolution seismic reflection images were successfully registered by using the hydrophones employed in the stream-water driven trench, and were effectively focused by applying optimal data processing sequences. The strategy included enhancement of the signal interfered with the large-amplitude scattering noise, through pre- and post stack processing such as time-variant filtering, bad-trace editing, residual statics, velocity analysis, and careful muting after NMO (normal moveout) correction. The major reflections including the bedrock surface were mapped with the desired resolution and were correlated to the seismic crosshole tomographic data. Shallow major reflectors could be identified and analyzed on the AGC (auto gain control)-applied field records. Three subhorizontal layers were identified with their distinct velocities; overburden (<3000 m/s), sediments (3000-4000 m/s), limestone bedrock (>4000 m/s). Taking into account of no diffraction effects in the field records, gravel-rich overburdens and sediments are considered to be well sorted. Based on the images mapped consistently on the whole survey line and seismic velocity increasing with depth, this area probably lacks in sizable cavities (if any, no air-filled cavities).

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.539-549
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• 2019

In 2016, Benthic Macroinvertebrates Streambed Index (BMSI) was proposed as an index to evaluate streams as benthic macroinvertebrate depending on the substrate type of streambed. However, orignal BMSI were selected without consideration of water quality. Analyzes without water quality do not constitute biological indices based solely on the substrate type of streambed. Therefore, in this study, the indicator value was improvement in consideration of water quality, and the distribution characteristics of benthic macroinvertebrates according to the substrate type of streambed were analyzed under relatively equal water quality conditions. We surveyed 20,155 sampling units in Korea from 2008 to 2018, and we re-estimated each lithophility of 191 taxa. As a result of estimating the streambed of each newly lithophilic value classification group considering the water quality, it was different from the original lithophilic value. Representative integer lithophilic values were newly calculated from 126 taxa among the 191 index taxa used in the analysis. The correlation between new constructed BMSI and community structure was compared and analyzed. It showed extreamely significance (p<0.001) in the dominance index, diversity index, abundance index, and evenness index of the community structure. Diversity index, abundance index, and evenness index showed positive correlation, and dominance index showed negative correlation. The correlation coefficient (r) was the highest in the richness index of about 0.664.

• Journal of Broadcast Engineering
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• v.5 no.2
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• pp.140-158
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• 2000

Testing of terrestrial Digital TV(DTV) broadcasting in Seoul and Kyung-gi region was started in May 1999. Tasks of the committee for DTV technical evaluation were to implement test procedures for DTV transmitting systems, to analyze various technical aspects of DTV and to complete a field test. This paper summarizes the field test results. The field test vehicle was designed and constructed to measure field data. We chose over 200 test points to verify the receiving status of DTV signals and compared them with the analog TV signals at the same site. The results showed stable and satisfactory reception of DTV signals over 70%. The system performance index was over 80%.

• Proceedings of the Technology Innovation Conference
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• 2009.02a
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• pp.259-274
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• 2009

연구개발에 종사하는 연구자나 연구기획자들은 미래에 어떤 기술 또는 연구 분야가 각광을 받을지 파악하기 위해 정보를 수집하거나 분석한다. 그러나 방대한 정보 중에서도 정말 필요한 정보를 단시간내에 효과적으로 수집하기는 쉽지 않다. 기술기획이나 연구기획의 경우 현재의 연구동향이나 현황을 빠른 시간안에 정확히 파악하는 것이 주된 관심사이며, 이것을 지원해 줄 수 있는 연구방법론 중 하나가 계량서지학이다. 본 연구는 계량서지적 분석결과를 효과적으로 이해할 수 있도록 시각화 기법을 이용한 정보분석 방법론을 다룬다. 발표동향 분석, 공동연구네트워크분석, 수준지수분석, 특허인용네트워크를 통한 인용트리분석 등을 이용하여 전자종이(e-Paper)기술분야에 대해 분석하였다. 본 연구는 정보분석에 있어 비전문가라도 신속하게 정보분석 결과를 획득할 수 있도록 KISTI에서 개발한 정보분석시스템인 KnowledgeMatrix S/W와 이를 응용한 S/W를 활용한 방법론을 제시한다. 본 연구에서 사용한 방법론들은 실제로 연구사업에 활용하고 있거나 활용가능성이 매우 높은 방법론을 이용하였기 때문에 향후에도 널리 활용될 수 있을 것으로 판단한다.

• The Journal of the Acoustical Society of Korea
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• v.9 no.4
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• pp.5-17
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• 1990

This study aims to establish the appropriate class and standards of sound insulation performance, which are suitable for domestic conditions. For, these purpose, field surveys were conducted, correlationship between subjective response and impact sound insulation performance and then, the applicability of ISO and JIS evaluation method was reviewed. As a result, the JISs method is more advisable than the ISO to evaluate Impact sound insulation performance of domestic apartment house and it is desirable to use both light and heavy weight source (tapping machine, tire) as standard impact sources. And, whether including 63Hz bandwidth or not, the difference was recognized very small in calculating impact sound insulation index of JIS A 1419.

• Journal of Korean Society on Water Environment
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• v.29 no.1
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• pp.114-126
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• 2013

The purpose of this study was to develop a Korean thermality index (KTI) based on the distribution patterns of benthic macroinvertebrates according to altitude and latitude. Analyzing seasonal data (4,853 sampling units) surveyed and collected during 2007 ~ 2011 at 846 sites in South Korea, we estimated thermal valency, thermal value and indicator weight value of 208 species. Among them, 40 species in 6 orders (Decapoda 1 species, Collembola 1 species, Ephemeroptera 5 species, Plecoptera 17 species, Diptera 3 species, Trichoptera 13 species) were selected as the candidate indicator species sensitive and vulnerable to warmth along with climate change. KTI and Benthic macroinvertebrate index (BMI) were tested at three clean streams (Hangye stream, Buk stream and Bangtae stream). KTI showed significant differences according to altitude and water temperature whereas the saprobity index BMI showed little differences. This result means that KTI can be applicable to assess the impact of water temperature independently of organic pollutants.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.532-536
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• 2004

최근 수자원개발의 한계와 수질의 오염으로 인하여 제한된 수자원의 적절한 배분과 지속 가능한 수자원의 이용이라는 문제가 크게 대두되고 있어 개발의 한계 속에서 수질을 보존하기 위한 노력이 필요한 시점이다. 그러나, 수량과 수질을 동시에 고려할 수 있는 수자원계획 도구는 흔치 않다. 이러한 종합적인 수자원계획 수립 및 분석을 위할 도구를 개발하기 위하여 한국건설기술연구원에서는 SEI-B(Stockholm Environment Institute - Boston Center)와 공동으로 기존에 SEI-B에서 개발된 WEAP(Water Evaluation And Planning System)을 국내 실정에 맞도록 수정보완 한 K-WEAP을 개발하였었다. 이를 바탕으로 본 연구에서는 K-WEAP에 수질 모의 기능을 추가하여 개발함으로써 수량-수질을 연계하여 수자원계획수립이 가능하도록 하였다. 개발된 K-WEAP은 원단위 개념을 이용한 발생량의 산정과 보존성 물질의 수질 모의와 일반적인 지수감소형 물질 및 BOD, DO 등과 같은 1차 분해성 물질의 모의가 가능하다. 이러한 기능을 이용하여 수자원 계획 시 수질등급을 만족시키기 위한 하수처리장의 설치 계획과 유역관리를 위한 여러 가지 대안의 수립이 가능하며, 여러 가지 대안에 대하여 장래 수질의 변화 경향을 비교 분석할 수 있는 기초 자료를 제공한다. 본 연구에서는 K-WEAP에 탑재된 수질 모형의 내용을 분석하고 수량과 수질의 통합과정을 알아본 후, 가상의 시험유역에 적용한 길과를 바탕으로 수량-수질 통합수자원계획의 적용성을 살펴보았다,

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.46-46
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• 2017

지역가뭄빈도분석의 분위산정에 대한 신뢰성은 수문학적으로 균일한 지역으로 구분하기 위해 사용된 장기간의 과거 자료와 분석절차에 의해 결정된다. 그러나 극심한 가뭄은 매우 드물게 발생하며 신뢰 할 수 있는 지역빈도분석을 위한 지속기간이 충분치 않는 경우가 많이 발생한다. 이 외에도 우리나라의 복잡한 지형적 및 기후적 특징은 동질한 지역으로 구분하기 위한 통계적인 처리방법이 필요하였다. 본 연구에서 적용한 지역빈도분석은 여러 지역의 다양한 변수인 수문기상 특성을 분석하여 동질한 지역을 확인하고, 주요 가뭄변수(지속 시간 및 심각도)를 통합 적용하여 각각의 동질한 지역 분위를 추정함으로써 동질한 지역을 구분하는 해결책을 제시하였다. 본 연구에서는 가우시안 혼합 모형(Gaussian Mixture Model)을 기반으로 기반 군집분석 방법을 적용하여 최적의 동질한 지역을 구분하고 그 결과를 우도비검정 및 다른 유효성 검사 지수를 이용해서 확인하였다. 가우시안 혼합 모델에서 산정했던 매개변수를 방향저감 공간으로 표현하기 위해서 가우시안 혼합 모델방향 저감(GMMDR)방법을 적용하였다. 이 변수는 가뭄빈도분석을 위해 다양한 분포와 코풀라(copula) 적합도를 이용하여 추정 비교하였다. 그 결과 우리나라를 4개의 동질한 지역으로 나누게 되었다. 가우시안과 Frank copula를 이용한 Pearson type III(PE3) 분포는 우리나라의 가뭄 기간과 심각도의 공동 분포를 추정하는데 적합한 것으로 나타났다.