• 한국해양공학회지
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• 제29권5호
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• pp.366-372
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• 2015

Ocean energy is one of the most promising renewable energy resources. In particular, South Korea is one of the countries where it is economically and technically feasible to develop tidal current power plants to use tidal current energy. In this study, based on the design code for HARP_Opt (Horizontal axis rotor performance optimizer) developed by NREL (National Renewable Energy Laboratory) in the United States, and applying the BEMT (Blade element momentum theory) and GA (Genetic algorithm), the optimal shape design and performance evaluation of the horizontal axis rotor for a 200-kW-class tidal current turbine were performed using different numbers of blades (two or three) and a pitch control method (variable pitch or fixed pitch). As a result, the VSFP (Variable Speed Fixed Pitch) turbine with three blades showed the best performance. However, the performances of four different cases did not show significant differences. Hence, it is necessary when selecting the final design to consider the structural integrity related to the fatigue, along with the economic feasibility of manufacturing the blades.

• 한국인터넷방송통신학회논문지
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• 제18권4호
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• pp.149-154
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• 2018

안정된 결혼문제에 대해서는 Gale과 Shapley 알고리즘(GSA)이 유일하게 알려져 왔다. 이 알고리즘은 남성이 자신이 가장 선호하는 여성에게 청혼하면 여성이 수락/거절하는 방식(MP)으로 남성 최적-여성 최악의 결과이지만 항상 안정된 매칭 결과를 얻는다. 남성을 여성으로 바꾸어 여성 청혼-남성 수락 방식(WP)을 적용하면 전혀 다른 결과를 얻을 수 있다. 또한 MP나 WP로도 최적의 안정된 매칭 결과를 얻지 못하는 경우도 발생한다. 본 논문에서는 MP와 WP의 이러한 문제점을 해결하기 위해 어떠한 경우라도 최적의 안정된 매칭 결과를 얻는 방법을 제안한다. 제안된 알고리즘은 여성 최악인 MP 결과에 대해 여성을 보상하기 위해 여성이 보다 선호하는 남성들을 대상으로 k명의 여성이 짝을 상호 교환하는 k-opt를 수행하는 방식을 제안하였다. 다양한 사례에 대해 실험을 한 결과 제안된 알고리즘은 MP나 WP로도 얻지 못하는 최적의 안정된 매칭 결과를 얻을 수 있었다.

• Journal of Animal Science and Technology
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• 제59권9호
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• pp.20.1-20.9
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• 2017

Background: Ribonuclease (RNase) is one of the few toxic proteins that are present constantly in snake venoms of all types. However, to date this RNase is still poorly studied in comparison not only with other toxic proteins of snake venom, but also with the enzymes of RNase group. The objective of this paper was to investigate some properties of RNase from venom of Vietnam cobra Naja atra. Methods: Kinetic methods and gel filtration chromatography were used to investigate RNase from venom of Vietnam cobra. Results: RNase from venom of Vietnam cobra Naja atra has some characteristic properties. This RNase is a thermostable enzyme and has high conformational stability. This is the only acidic enzyme of the RNase A superfamily exhibiting a high catalytic activity in the pH range of 1-4, with $pH_{opt}=2.58{\pm}0.35$. Its activity is considerably reduced with increasing ionic strength of reaction mixture. Venom proteins are separated by gel filtration into four peaks with ribonucleolytic activity, which is abnormally distributed among the isoforms: only a small part of the RNase activity is present in fractions of proteins with molecular weights of 12-15 kDa and more than 30 kDa, but most of the enzyme activity is detected in fractions of polypeptides, having molecular weights of less than 9 kDa, that is unexpected. Conclusions: RNase from the venom of Vietnam cobra is a unique member of RNase A superfamily according to its acidic optimum pH ($pH_{opt}=2.58{\pm}0.35$) and extremely low molecular weights of its major isoforms (approximately 8.95 kDa for RNase III and 5.93 kDa for RNase IV).

• Applied Biological Chemistry
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• 제18권1호
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• pp.42-51
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• 1975

돼지감자 시료(試料)(Putrefactived and dry Jerusalem artichoke)로 부터 강력(强力)한 Inulin가수분해(加水分解) 효소(酵素)를 생산(生産)하는 Penicillium sp. I을 분리선발(分離選拔)하였고 본균(本菌)을 사용(使用)하여 효소생산(酵素生産)에 관(關)한 최적배양조건(最適培養條件)을 검토(檢討)하여 다음과 같은 결론(結論)을 얻었다. 1. Penicillium sp. I은 Inulase생산력(生産力)이 강(强)한 균주(菌株)이다. 2. 본균(本菌)의 Inulase생산(生産)을 위한 최적배양(最適培養) 조건(條件)을 Jerusalem artichokoke extract media와 Basal media의 두 배양기(培養基)에서 결정(決定) 하였다. 3. Jerusalem artichoke extract media에서 Basal media보다 Inulase생산력(生産力)이 높았다. 4. Inulase생산능(生産能)도 Jerusalem artichoke extract media에서는 4일(日) Basal media에서는 5일(日) 배양(培養)으로써 최고치(最高値)에 도달하였다. 5. Inulin농도(濃度), pH. 온도조건(溫度條件) Jerusalem artichoke extract media에서는 opt. temp $30^{\circ}COpt.$ pH 5.0, Opt. conc 4.0%(W/V)로 나타나고 Basal media에서는 Opt temp $30{\sim}33^{\circ}C$, Opt. pH $5.0{\sim}6.0$, Opt conc $1.0{\sim}1.5%(W/V)$ 6. 질소원(窒素源)으로서는 Corn Steep Liquir, Peptone, $(NH_4)_2HPO_4,\;NH_4H_2PO_4,\;(NH_4)_2SO_4$등이 량호(良好)하고 특히 유기질소원(有機窒素源)을 가(加)함으로써 Basal meaia에서 Inulase생산(生産)을 증가(增加)시켰다. 7. 당원(糖源)의 이용(利用)으로써는 Inulin이외(以外)의 제당(諸糖)은 Inulase생산(生産)에 영향(影響)을 미치지 않았다. 8. 금속(金屬) 염류(鹽類)의 이용(利用)은 KCI. $MgSO_4,\;FeSO_4$등이 Inulase생산(生産)을 증가(增加)시켰다.

• Nutrition Research and Practice
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• 제8권6호
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• pp.638-643
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• 2014

BACKGROUND/OBJECTIVES: Kimchi is a traditional Korean fermented vegetable containing several ingredients. We investigated the protective activity of methanol extract of kimchi under different fermentation stages against oxidative damage. MATERIALS/METHODS: Fresh kimchi (Fresh), optimally ripened kimchi (OptR), and over ripened kimchi (OvR) were fermented until the pH reached pH 5.6, pH 4.3, and pH 3.8, respectively. The radical scavenging activity and protective activity from oxidative stress of kimchi during fermentation were investigated under in vitro and cellular systems using LLC-$PK_1$ cells. RESULTS: Kimchi exhibited strong radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl, nitric oxide, superoxide anion, and hydroxyl radical. In addition, the free radical generators led to loss of cell viability and elevated lipid peroxidation, while treatment with kimchi resulted in significantly increased cell viability and decreased lipid peroxidation. Furthermore, the protective effect against oxidative stress was related to regulation of cyclooxygenase-2, inducible nitric oxide synthase, nuclear factor-${\kappa}B$ p65, and $I{\kappa}B$ expression. In particular, OvR showed the strongest protective effect from cellular oxidative stress among other kimchi. CONCLUSION: The current study indicated that kimchi, particularly OptR and OvR, played a protective role against free radical-induced oxidative stress. These findings suggest that kimchi is a promising functional food with an antioxidative effect and fermentation of kimchi led to elevation of antioxidative activity.

• Applied Biological Chemistry
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• 제42권3호
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• pp.252-255
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• 1999

Chalcones 유도체들을 합성하고 farnesyl protein transferase(FPTase) 저해활성을 측정하여, 기질분자의 치환기 변화에 따른 구조와 활성과의관계(SAR)를 Free-Wilson법과 Hansch법으로 검토하였다. Benzoyl group 중 X-치환기가 styryl중 Y-치환기보다 활성에 더욱 큰 영향을 미쳤으며 meta- > ortho-, para-치환기의 순으로 활성을 나타내었다. 또한, X및 Y-치환기의 소수성이 적정값$(({\Sigma}logP)_{opt}\;=\;3.915)$에 근접할수록 활성이 증가 하였으며, X-치환기의 입체효과와(Es > O) 전자밀게 Y-치환기에 의한 공명효과(R < O)가 활성에 미치는 중요한 요소로 인식되었다. 다루어진 화합물중에서 비 치환체, 8은 가장 높은 FPTase저해활성$(pl_{50}\;=\;4.30)$을 나타내었다. 그리고 기질 수용체간의 상호작용을 가정하여 제안하였다.

• 통상정보연구
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• 제18권4호
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• pp.195-217
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• 2016

국제물품매매계약에 관한 유엔협약(CISG)은 국제매매의 통일적인 법창출을 통하여 국제무역을 증진시키기 위한 국제조약이다. CISG는 상이한 체약국에 영업소를 둔 당사자간 물품매매계약에 적용된다. 일방당사자가 하나 이상의 영업소가 있는 경우, 영업소는 계약과 이행에 가장 밀접한 관련이 있는 곳이다. 그러나 영업소가 갖는 중요성에도 불구하고 CISG는 아무런 정의를 내리고 있지 않다. 영업소에 대한 정의의 부재는 당사자들의 계약에 CISG를 적용할 것인지 여부를 결정함에 있어 여러 문제들을 야기시킨다. 또한 양 당사자는 CISG 적용을 배제할 수 있다. 그러나 CISG는 당사자들이 명시적으로 배제해야하는지 혹은 묵시적으로도 가능한지를 규정하지 않고 있다. 어떻게 유효하게 CISG를 배제할 수 있는지 살펴볼 필요가 있다. 미국법에 의거하여 CISG는 자기집행조약이다. 따라서 CISG의 규정들은 국제물품매매계약에 실체법으로써 직접 적용된다. 하지만 CISG의 정치적 그리고 경제적 중요성에도 불구하고 미국법원을 이를 간과하고 있다. 본 연구는 우리 기업들의 CISG 적극적인 활용을 위하여 미국법원에서 CISG를 어떻게 인식하고, 해석 및 적용하는지를 판례를 통하여 살펴보았다.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2003년도 International Symposium
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• pp.65-89
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• 2003

Next Highly sophisticated communication generation of the Advanced Electronics and Imaging processing society will require a vast information volume and super high speed signal transport and information instruction. This means that super high technology should be created for satisfying the demand. It's also required the high reliability of the communication system itself, It will be supported the new advanced packaging technology of the 3 Dimensional structured system and system integration technology. Here is introduced the new 3 Dimensional technology for IC nnd LSI packaging and Opt-electronics Packaging of ASET activity in Japan.

• Journal of the Korean Wood Science and Technology
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• 제48권2호
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• pp.196-205
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• 2020

The purpose of this study was to investigate a method for improving the physical and mechanical properties of laminated board made from oil palm trunk (OPT). The effects of pretreating the lamina with heat-pressure and altering the lamina composition of the laminated board were investigated. The outer third of OPT in cross-section had high-density wood, while the underlying third had low to medium density. The hot press was applied to pretreat the lamina that had low to medium density. The lamina were 1.5 cm in thickness, 5 cm in width, and 65 cm in length. The hot press was applied at 2.94 MPa or 4.41 MPa at 150 ℃ for 60 minutes, and the target thickness of the lamina was 1 cm. The three layers of the laminated board samples were bonded with isocyanate adhesive at a glue spread of 300 g/㎡ and cold pressed at 0.98 MPa for 3 h. The laminated board samples were tested according to Japanese Agricultural Standard (JAS) 234-2003. The results showed that the densification of the inner lamina did not significantly affect the physical-mechanical properties of the laminated board produced. However, the laminated board made with high-density laminas for the outer layers fulfilled the JAS 234-2003 standard for the modulus of elasticity and the modulus of rupture.

• 대한의생명과학회지
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• 제16권4호
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• pp.247-258
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• 2010

The objective of this research was to evaluate the relationships of preoperative (Pre-OP) levels of hematological and biochemical indices to perioperative variables in patients that underwent coronary artery bypass graft surgery (CABG). Pre-OP levels of hematological factors [total white blood cells (T-WBC), erythrocytes, hemoglobin, hematocrit, glycohemoglobin A1c (HbA1c), or platelet] were negatively or positively related with biochemical indices [alanine aminotransferase (ALT), bilirubin, glucose, fructosamine, triglyceride, and high density lipoprotein cholesterol (HDL)]. Pre-OP levels of hematological factors and biochemical indices were negatively or positively correlated with echocardiographic variables. Pre-OP level of HbA1c had a relationship with C-reactive protein. Pre-OP levels of aspartate aminotransferase (AST), ALT, HDL, glucose, fructosamine, or blood urea nitrogen (BUN) were positively or negatively associated with Pre-OP levels of cardiac markers (brain natriuretic peptide, troponin-I, creatine kinase isoenzyme 2, or CRP). Pre-OP levels of hematological factors (excepting T-WBC) related with operation time (OPT), postoperative mechanical ventilation time (POMVT), intensive care unit-period (ICU-period) or hospitalization. Pre-OP levels of AST, ALT, bilirubin, triglyceride, HDL, low dwensity lipoprotein, fructosamine, or BUN were positively or negatively correlated with OPT, graft numbers, POMVT, ICU-period or hospitalization. Retrospective this study reveals that Pre-OP levels of hematological and biochemical markers are associated with echocardiographic variables, several cardiac markers and postoperative outcomes, suggesting that Pre-OP levels of hematological and biochemical markers may be useful predictors for the diagnosis and prognosis of coronary artery disease.