• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.441-445
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• 1993

This study addresses the wear characteristics of electro-rheological(ER) fluids which are potential application candidates for various hydraulic systems. As the first step, three different ER fluids are composed and subsequently tested to observe field-dependent Bingham behaviors. The pin-on-disc testing method is then adopted herein herein to investigate the wear rate of the ER fluids with various base liquids and particle concentrations. In addition, friction coefficients for the ER fluids are evaluated with respect to the normal force.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.1068-1071
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• 1993

An algorithm of fuzzy predictive sliding control is proposed to design a jet engine control system. Sliding control using predictive scheme is adopted to compensate the time delay of fuel injector. Fuzzy rule-base is also introduced to adjust the command input for suppressing the surge. The potential of the proposed algorithm is shown through simulations utilizing a typical engine-only model.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.3-6
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• 2003

Fusion technology is a key to maximize innovative potential of geoscience for many challenging issues today that require integrated multi-disciplinary approach. Successful fusion technological advance can be achieved when interdisciplinary cooperation is firmly established. In order to establish firm the context of inter-disciplinarity that is still feeble, it is urgent to continuously develop geoscientific models and systematic infra for interdisciplinary cooperation such as well-prepared geo-spatial database and knowledge base network that can support multi-lateral cooperation between multiple disciplines and multi-phase international cooperation.

• 지역연구
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• 제13권2호
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• pp.119-141
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• 1997

This study aims to identify the role of science park for technology commercialization and business promotion. After theoretical review about science park and technology commercialization, the instruments for stimulating entrepreneurship and business in science park are described. The experience of Taedok Science Town is examined in terms of main sectors of activities, universities as base for technology transfer and the potential for technology commercialization. In conclusion, the complex model is suggested as the development strategy for business incubation in accordance with the stages of development and active technology commercialization.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.543-549
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• 2000

Water quality was monitored from a watershed with small-scale livestock production farms. To evaluate pollution potential, land use, population, the size of livestock production of each farm, and livestock management were surveyed. Climate and stream flow data were gathered. Water samples were taken periodically for base conditions and some storm events. Pollutant loading was estimated by flow volume and concentrations of constituents.

• 산업경영시스템학회지
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• 제34권4호
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• pp.114-119
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• 2011

Process capability indices (PCls) have been widely used in manufacturing industries to provide a quantitative measure of process potential and performance. The previous studies have measured only one location on each part in the case of single variate. To calculate the reliable process capability, a couple of measuring locations on each part are required. In this paper, we propose a new system process capability index $SC_{pm}$ (m) which is the minimum value of the location PCls.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제1호
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• pp.33-36
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• 2001

Only do we have an earth! It is crucially important to improve our living environment and keep the sustained development of a city in the limited space. Some concrete examples will be analysized in the paper, elaborating upon how to make full use of roof space and various plants to create a better green-space. To create different activity space with unique characteristics for people, various plants, roof-space, water and buildings in the style of garden should be use when local conditions and design requirement should be considered.

• Corrosion Science and Technology
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• 제14권2호
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• pp.54-58
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• 2015

A heavy oil of low quality has been mainly used in the diesel engine of the merchant ship as the oil price has been significantly jumped for several years. Thus, a combustion chamber of the engine has been often exposed to severely corrosive environment more and more because temperature of the exhaust gas of the combustion chamber has been getting higher and higher with increasing of using the heavy oil of low quality. As a result, wear and corrosion of the engine parts such as exhaust valve, piston crown and cylinder head surrounded with combustion chamber are more serious compared to the other parts of the engine. Therefore, an optimum repair welding for these engine parts is very important to prolong their lifetime in a economical point of view. In this study, 1.25Cr-0.5Mo filler metal was welded with SMAW method in the forged steel which would be generally used with piston crown material. And the corrosion properties of weld metal, heat affected and base metal zones were investigated using electrochemical methods such as measurement of corrosion potential, anodic polarization curves, cyclic voltammogram and impedance etc. in 35% $H_2SO_4$ solution. The weld metal and base metal zones exhibited the highest and lowest values of hardness respectively. And, the corrosion resistance of the heat affected and weld metal zones was also increased than that of the base metal zone. Furthermore, it appeared that the corrosive products with red color and local corrosion like as a pitting corrosion were more frequently observed on the surface of the base metal zone compared to the heat affected and weld metal zones. Consequently, it is suggested that the mechanical and corrosion characteristics of the piston crown can be predominantly improved by repair welding method using the 1.25Cr-0.5Mo electrode.

• 디지털융복합연구
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• 제12권1호
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• pp.127-139
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• 2014

본 연구의 목적은 스마트폰 운영체제의 지배적 디자인을 결정하는 주요 요인이 무엇인지 제시하고 제시된 요인들과 사용만족 간의 논리적 인과관계를 검증하는데 있다. 이를 위해 지배적 디자인을 결정하는 스마트폰 운영체제의 주요 결정요인을 OS호환성, OS향상성, 사용자기반, 그리고 네트워크 효과 등으로 제시했다. 그리고 사용만족과의 논리적 인과관계를 실증분석했다. 연구결과, 스마트폰 운영체제의 OS호환성과 OS향상성은 사용기반 확대에 긍정적인 영향을 미치는 것으로 나타났다. 특히 OS향상성은 사용기반을 확대 시킬 뿐만 아니라 네트워크 효과를 강화시키는 원인으로 나타났다. 그리고 직접적으로 사용만족에도 긍정적인 영향을 미치는 것으로 나타났다. 연구결과는 그동안 실증연구가 이루어지지 않았던 운영체제의 지배적 디자인 결정과정에 대해 논리적 인과관계를 제시하여 학문적으로 뿐만 아니라 실무적으로도 크게 기여했다고 판단된다.

• 대한치과기공학회지
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• 제25권1호
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• pp.9-20
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• 2003

Using a nickel-chrome casting alloy called 'Rexillium V' which is also available as base metal alloy for dental ceramic crown, 4 types of mixtures(A, B, C, D) with old and new metal were prepared for cyclic casting. The results of cyclic casting can be outlined as follows: 1. For Vickers hardness after casting, specimen A and D tended to have lower hardness in the course of cyclic casting, while specimen B and C tended to higher hardness. 2. The results of X-ray diffraction analysis showed that major crystal phase contained nickelchrome compounds and carbide. 3. The observation results of SEM photographs after cyclic casting show that there was a significant tendency to have similar structures among experimental groups. 4. The results of EDX analysis after cyclic casting showed that there were little differences in chemical composition between parent metal and base metal alloy. Although industrial nickel-chrome cast alloy did not show any significant change in material properties even through cyclic casting over several times, it is recommended that more there be more in-depth studies on how to detect any potential corrosion, discoloration and toxication of dental ceramic crown implanted in patient's oral cavity.