• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.663-669
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• 2012

The nucleophilic substitution reactions of dibutyl chlorophosphate (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $55.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs; kH/kD) are secondary inverse ($k_H/k_D$ = 0.86-0.97) with the strongly basic anilines while primary normal ($k_H/k_D$ = 1.04-1.10) with the weakly basic anilines. The DKIEs, steric effects of the two ligands, activation parameters, cross-interaction constants, variation trends of the kH/kD values with X, and mechanism are discussed for the anilinolyses of the nine ($R_1O$)($R_2O$)P(=O)Cl-type chlorophosphates. A concerted mechanism is proposed with a backside nucleophilic attack transition state for the strongly basic anilines and with a frontside attack involving a hydrogen-bonded four-center-type transition state for the weakly basic anilines on the basis of the magnitudes, secondary inverse and primary normal, and variation trends of the $k_H/k_D$ values with X.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.14 no.2
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• pp.137-140
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• 2011

Research and development (R&D) is very important to acquire new knowledge in various fields. The significance of public R&D is also increasing, especially related to health policy making, establishing basic databases, and enhancing basic and clinical science. The total budget of general public R&D in Korea was approximately ten billon US Dollars in 2008, but the proportion of health care research was just below 10%. In private sectors, it was three times the amount allocated to the public budget. In this article, recent trends in public R&D in Korea, especially related to health care policy and biotechnology are summarized. A brief overview of the application process for a specific policy fund is also described for early-stage researchers in these fields.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.564-567
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• 2004

The government has focused the national R&D investment on 6T areas - IT(Information Technology), BT(Bio Technology), NT(Nano Technology), ST(Space Technology), ET(Environment ${\cdot}$ Energy Technology), CT(Culture Technology). The paper summarizes patents and utility models in these areas which are applied in past decade. This study presents the relationship of the patent trends and the national R&D investment in 6T areas.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.8
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• pp.924-931
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• 2007

Now, there are two big issues threatening global society, which are the depletion of fossil fuels and the environmental disruption. Therefore, marine diesel engine, taking up over 95% share of the marine power market, has met the environmental and economical problems, too. These problems have caused a necessity of new, alternative power systems in ships and fuel cell systems has been playing a central role as one of the alternatives. This paper analyzes the characteristics of marine fuel cell systems, R&D trends of advanced countries, and mapping out R&D strategy of Korea.

• Journal of Communications and Networks
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• v.4 no.4
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• pp.321-335
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• 2002

Emergence of the fourth generation mobile communication system (4G system) is now in its dawn. This article proposes a perspective framework on the 4G system, and discusses various kinds of system aspects and technological requirements in terms of novel service features, spectrum management, radio access technologies, wired access integration, core network, and mobile terminal. The focus of the article is to define the scope and features of the 4G system in an overall system/network viewpoint. From the foreseeable development trends, it is highly expected that whatever emerges in the 4G system will be some kind of constantly evolving and grand recursive concatenation of all the existing system/network developments.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2054-2056
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• 1999

We surveyed the recent technical trends concerning high-Tc superconducting(HTS) Power cable R&D around the world, and proposed the course the HTS power cable R&D in Korea should take. The HTS power cable R&D in Korea need be started as soon as posible with focusing on the development and field test of the economical HTS conductors.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.206-210
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• 2005

As design trends has changed to have flexible aft hull structure, increased power output and stiffer shafting system, owners and classification societies have more concerned about shaft alignment. In the shaft alignment analysis, there are many uncertainties which are related in propeller generated force, bearing stiffness, crank shaft model and etc. in this study, it is focused on the effect of crankshaft model by comparing between equivalent model and actual crankshaft model.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.531-533
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• 2003

변전소는 에너지 측면에서 볼 때 에너지를 연계하거나 분리 또는 변환하는 지점에 설치되어지며 변전소 자동화 시스템은 이러한 변전소의 주요 기기들이나 각 피더를 감시하고 보호하는 역할을 수행하게 된다. Microprocessor 기술의 발전과 통신기술 및 프로그래밍 기술의 발전을 통하여 변전소의 시스템 또한 90년경부터 디지털화가 가속되어 그 시스템 또한 구조적으로 변화하게 된다. 기존 아날로그 시스템의 경직된 구성에서 탈피하여 변화의 속도 또한 점차 증가하고 있으며 이러한 흐름을 파악하기 위해 변전소 자동화 시스템의 현재 발전 상황과 앞으로의 변화 방향에 대하여 서술한다.

• Current Photovoltaic Research
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• v.6 no.4
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• pp.94-101
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• 2018

Light elevated temperature induced degradation (LeTID) was noted as an issue in multi-crystalline silicon solar cells (MSSC) by Ram speck in 2012. In contrast to light induced degradation (LID), which has been researched in silicon solar cells for a long time, research about both LeTID and the mechanism of LeTID has been limited. In addition, research about LeTID in single-crystalline silicon solar cells (SSSC) is even more limited. In order to improve understanding of LeTID in SSSC with a passivated emitter rear contact (PERC) structure, we fabricated four group samples with boron and oxygen factors and evaluated the solar cell characteristics, such as the cell efficiency, $V_{oc}$, $I_{sc}$, fill factor (FF), LID, and LeTID. The trends of LID of the four group samples were similar to the trend of LeTID as a function of boron and oxygen.

• 축산식품과학과 산업
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• v.10 no.2
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• pp.42-52
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• 2021