• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.394-402
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• 2013

The new complex catalysts were synthesized by the reaction of titanium compounds (titanium chloride or titanium butoxide) and diamines in this work, and they showed very high catalytic activities for the cyclododecatriene (CDT) synthesis from 1,3-butadiene through trimerization. CDT synthetic reaction was performed in an autoclave reactor, and the effects of reaction temperature, type of catalyst, catalyst amount added into the system, the mole ratio of Al/Ti and immobilization method were investigated on the yield of product CDT. The titanium complex catalyst combined to diamine with 1:1 ratio showed high selectivity to CDT more than 90%. The ratio of TTT-CDT/TTC-CDT isomers in the product revealed as different values, depending on the type of diamine combined to titanium and Ti/diamine ratios. Those homogeneous complexes could be used as a heterogenized catalyst after anchoring on the supports, and the immobilized titanium catalyst retained the catalytic activities for several times in the recycled reactions without leaching. The carbon support containing titanium has exhibited superior activity to the silica support. Especially, when the titanium complex was anchored on the support which was fabricated by the hydrolysis of tripropylaminosilane itself, the resulting titanium catalyst showed the highest BD conversion and CDT selectivity.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.445-450
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• 1975

These experiments were carried out to obtain useful yeast for Korean grape wine brewing. The 213 strains of yeasts were isolated from grapes sampled in Daejeon city and suburbs and then 3 strains among the isolated yeasts were selected as useful strains and identified. The results obtained as follows; 1. The 3 strains of W-49, W-50 and W-127 selected as useful yeasts were clarified to grape wine mash rapidly. 2. In the mashes clarified after storage of 45 days, the value of optical density of the case of W-50 strain was highest and the color was very thick, compared with the case of another strains. 3. In the pannel test of the grape wines, the case of W-49 and W-50 strains were best, the case of the W-127 strain and control yeast, Hb were similar each other as next order. 4. Among 3 strains selected as useful yeasts it were identified that the strains of W-49, W-50 selected as useful strains were Saccharomyces cerevisiae and the strain of W-127 was Saccharinyces pretoriencis by the Ladder manual. 5. All of these useful yeasts were appeared red color on TT C stain.

• Electronics and Telecommunications Trends
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• v.12 no.2 s.44
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• pp.103-118
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• 1997

최근 국제표준화기구인 ITU를 비롯해 ETSI, T1 Committee, TTA, TTC, ATSC, TSACC 등 각 지역 표준화 기구 (Participating Standardization Organization: PSO)들은 빠른 기술개발에 따른 적기의 표준공급 및 전자적인 표준화문서유통을 통한 신속한 표준제정을 위해 EDH(Electronic Document Handling)라는 전자정보유통시스템을 구축하고 기고서 및 표준문서 등 표준화 진행에 관련된 각종 정보를 전자적으로 검색하고 처리할 수 있는 환경을 구축하는데 많은 노력을 기울이고 있다. 이와 관련하여, 본 고에서는 제2차 세계전기통신표준총회(WTSC-96)에서 가장 활발하게 논의된 사항 중의 하나인 ITU-T/TSAG/EDH 관련 표준화 활동 현황을 고찰하고, 향후 EDH의 방향을 소개하고자 한다.

• Electronics and Telecommunications Trends
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• v.10 no.3 s.37
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• pp.101-123
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• 1995

최근 정보통신 기술 및 제품의 수명주기가 점점 단축됨에 따라 기업들간 컨소시움 형성, 다양한 포럼의 장 등을 통한 사전표준화가 정보통신전반에 걸쳐 광범위하게 추진되고있다. 이는 표준화가 국내외 정보통신시장의 선점 및 첨단기술개발주도권 확보를 위한 효과적이고 실질적인 수단이 되고 있음을 의미한다. 이와 같은 환경변화는 국가 차원의 적실한 표준화 전략계획수립의 필요성을 더욱 크게 하고 있다. 본 고에서는 정보통신표준화 전략계획 수립을 위한 정보통신표준화 대상의 우선순위결정방법을 분석하기 위해, 주요표준화기구들(ITU, ETSI, T1, TTC, TTA)의 표준화 전략 및 과제추진현황 등을 중심으로 조사분석하였다,

• Electronics and Telecommunications Trends
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• v.14 no.6 s.60
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• pp.134-149
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• 1999

정보화 사회의 정치.경제.사회.문화분야들은 정보통신 기술의 급속한 발전에 따라 불가분의 관계를 맺으며 발전을 가속화하고 있다. 이 중 표준은 제품 및 서비스간의 상호운용성 확보 및 증진이라는 기본적인 역할을 넘어서 국가 경쟁력의 우위확보를 위한 전략적 도구로서, 또한 자국산업을 보호하는 수단으로써 인식되어 각자 국제표준화무대에서 최선을 다하고 있다. 1965년 설립된 ITU는 130여년의 역사를 지닌 국제표준화 기구로서 전기통신의 발전사를 그대로 반영하고 있으며, 이 밖에도 세계표준화활동은 미국을 중심으로 하는 북미, EU를 중심으로 유럽, 아시아 지역의 일본 등 3자 구도로 운용되고 있다. 본 고에서는 국제표준화 기구인 ITU, 유럽의 ETSI, 미국의 T1, 일본의 TTC와 더불어 우리나라의 TTA의 조직 및 표준화 절차를 상세히 분석.고찰함으로써 국내 전문가들의 국제표준화 활동에 도움이 되고자 한다.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.4
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• pp.191-197
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• 2004

This paper presents experimental results for human drivers' driving patterns and an Adaptive Cruise Control(ACC) strategy. Analyses have shown that female drivers' driving characteristic values such as time-gap and minimum clearance are larger than those of male drivers'. Human drivers tend to have more clearance margins at high speed than at low speed. At low speed, drivers are much more sensitive to the desired clearance than at high speed. A multi-vehicle detection method is presented to improve ride quality of an ACC. Simulation results have shown that the proposed ACC can provide superior performance compared to the ACC strategy which uses a single-vehicle detection method.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.43-48
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• 2013

Oreorchis coreana Finet is threatened globally by over-collection from its natural habitats for horticultural purposes. Its rarity in nature makes this plant one of the most endangered species in Korea. In this study, we investigated the effects of sodium hypochlorite (NaOCl) on orchid seed viability and seed germination. An in vitro bioassay swelling test using immature seeds was compared with a standard chemical procedure using triphenyl tetrazolium chloride (TTC) to test seed viability. In general, the bioassay was more appropriate for estimating embryo viability after a prolonged pre-treatment (more than 1 h) in 1% NaOCl, a surface sterilant often used to enhance germination of seeds of terrestrial plants. Therefore, an efficient method for investigating in vitro swelling of immature seeds is urgently needed. We established a method for determining the viability and swelling of O. coreana seeds via in vitro examination of immature seeds. Treatment of immature seeds with 1% NaOCl for 10 min greatly enhanced the extent of swelling of immature zygote embryos when compared to untreated seeds. These data obtained here appear to be comparable to viability and swelling that occurs in O. coreana seeds via asymbiotic germination.

• Progress in Medical Physics
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• v.22 no.1
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• pp.42-51
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• 2011

Nuclear medicine images (SPECT, PET) were widely used tool for assessment of myocardial viability and perfusion. However it had difficult to define accurate myocardial infarct region. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using polar map with adaptive threshold. Rat myocardial infarction model was induced by ligation of the left circumflex artery. PET images were obtained after intravenous injection of 37 MBq $^{18}F$-FDG. After 60 min uptake, each animal was scanned for 20 min with ECG gating. PET data were reconstructed using ordered subset expectation maximization (OSEM) 2D. To automatically make the myocardial contour and generate polar map, we used QGS software (Cedars-Sinai Medical Center). The reference infarct size was defined by infarction area percentage of the total left myocardium using TTC staining. We used three threshold methods (predefined threshold, Otsu and Multi Gaussian mixture model; MGMM). Predefined threshold method was commonly used in other studies. We applied threshold value form 10% to 90% in step of 10%. Otsu algorithm calculated threshold with the maximum between class variance. MGMM method estimated the distribution of image intensity using multiple Gaussian mixture models (MGMM2, ${\cdots}$ MGMM5) and calculated adaptive threshold. The infarct size in polar map was calculated as the percentage of lower threshold area in polar map from the total polar map area. The measured infarct size using different threshold methods was evaluated by comparison with reference infarct size. The mean difference between with polar map defect size by predefined thresholds (20%, 30%, and 40%) and reference infarct size were $7.04{\pm}3.44%$, $3.87{\pm}2.09%$ and $2.15{\pm}2.07%$, respectively. Otsu verse reference infarct size was $3.56{\pm}4.16%$. MGMM methods verse reference infarct size was $2.29{\pm}1.94%$. The predefined threshold (30%) showed the smallest mean difference with reference infarct size. However, MGMM was more accurate than predefined threshold in under 10% reference infarct size case (MGMM: 0.006%, predefined threshold: 0.59%). In this study, we was to evaluate myocardial infarct size in polar map using multiple Gaussian mixture model. MGMM method was provide adaptive threshold in each subject and will be a useful for automatic measurement of infarct size.

• Journal of fish pathology
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• v.19 no.2
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• pp.127-139
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• 2006

From 2002 to 2004, various vibrios were isolated from the olive flounder, Paralichthys olivaceus of culturing size with disease signs. During this survey, it was known that the high proportion of Vibrio ichthyoenteri was occupied among the isolated vibrios. Generally, V. ichthyoenteri is well known as the pathogen of bacterial enteritis of olive flounder larvae. The aim of the present study was the compare the characteristics of two groups of V. ichthyoenteri, culturing sized olive flounder, and larvae of olive flounder showing the intestinal necrosis. The research was focused on the physiology, biochemistry, genetics in the two bacterial groups. The physiological and biochemical characteristics of the tested strains were very similar. The intergenic spacer (IGS) region between the 16S and 23S rRNA genes of 21 isolated strains and 3 reference strains, V. ichthyoenteri, were investigated by PCR fragment length typing and DNA sequencing. After the isolated strains were identified as V. ichthyoenteri, not only phenotypic characteristics of the isolated and reference strains but also homology of 16S-23S IGS of all isolated strains and reference strains as 99.1~100%. The V. ichthyoenteri showed 4 specific 16S-23S patterns and contained no-tRNA, tRNAGlu(TTC) , tRNAIle(GAT) tRNAAla(TGC) type .

• Journal of Korean Neurosurgical Society
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• v.41 no.1
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• pp.30-38
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• 2007

Objective : To elucidate the role of aquaporin-4[AQP4] in cerebral edema formation, we studied the expression and subcellular localization of AQP4 in astrocytes after focal cerebral ischemia. Methods : Cerebral ischemia were induced by permanent middle cerebral artery[MCA] occlusion in rats and estimated by the discoloration after triphenyltetrazolium chloride[TTC] immersion. Change of AQP4 expression were evaluated using western blot. Localization of AQP4 was assessed by confocal microscopy and its interaction with ${\alpha}-syntrophin$ was analyzed by immunoprecipitation. Results : After right MCA occlusion, the size of infarct and number of apoptotic cells increased with time. The ratio of GluR1/GluR2 expression also increased during ischemia. The polarized localization of AQP4 in the endfeet of astrocytes contacting with ventricles, vessels and pia mater was changed into the diffuse distribution in cytoplasm. The interactions of AQP4 and Kir with ${\alpha}-syntrophin$, an adaptor of dystrophin complex, were disrupted by cerebral ischemia. Conclusion : The deranged spatial buffering function of astrocytes due to mislocalized AQP4/Kir4.1 channel as well as increased assembly of $Ca^{2+}$ permeable AMPA receptors might contribute to the development of edema formation and the excitotoxic neuronal cell death during ischemia.