• 한국자동차공학회논문집
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• 제6권5호
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• pp.66-74
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• 1998

The operating torque and tribological characteristics of a cam/tappet system of an I.C. engine have an important effect on the engine efficiency. More power is lost for higher operation torque which is affected by the friction of a cam/tappet system. In this work experimental investigation of the torque behavior of a cam/tappet system was conducted to get tribological characteristics. Specifically, the torque was measured with respect to oil temperature and camshaft speed. The torque decreased with increasing camshaft speed because of decreasing friction coefficient but was hardly affected by the oil temperature. Also, the torque was the largest near the cam nose region.

• 한국생산제조학회지
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• 제9권1호
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• pp.30-37
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• 2000

In this paper rapid prototyping and precision casting technology have been developed for the manufacturing of inlet gear box of an airplane, Rapid prototyping is a new prototyping technology that produces complicated parts directly from three-dimensional CAD data with a high efficiency and has been extensively applied to various manufacturing processes. In the present work Selective Lase Sintering(SLS) system is utilized in order to manufacture prototype of the inlet gear box. Prototyping technology using SLS is also investigated from the viewpoint of accuracy. Using the SLS master the casting products are manufactured through several processes such as : vacuum casting lost wax shell casting and investment cast-ing. The shrinkage characteristics of wax and cast iron in the casting procedures are considered and then reflected to the design procedure so that the accuracy of the product is improved consequently.

• Architectural research
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• 제11권1호
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• pp.1-6
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• 2009

While the ideal universality of the modern period has achieved outstanding results in terms of establishing sanitary cities in contemporary urban environments, it has caused the decline of the genius loci. This study raises the question of the lost sense of place and proposes a solution, 'The Human-Environmental Ecological City'. The Human-Environmental Ecological City, called 'Ecoumenal City', does not provide a fake idealism with the conclusion of modernity of non-place or sense of place without modernity. It is both cosmological and geogenic, and the technology of the time is projected onto it human-environmentally. It does not pursue any more a urban planning as the overall work of an individual, but it aims at a balance rediscovered through the individual spontaneousness.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.288-289
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• 1992

The method of simulated annealing is a technique that has recently attracted significant attention as suitable for optimization problem of very large scale. If the temperature is too high, then some of the structure created by the heuristic will be destroyed and unnecessary extra work will be done. If it is too low then solution is lost, similar to the case of a quenching cooling schedule in the Simulated Annealing (SA) phase. Therefore, a crucial issue in this study is the determination of the starting temperature and cooling schedule for SA phase.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.829-830
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• 2008

In modern days, many of the images are captured by using various devices, such as PDA, digital camera, or cell phone camera. Because all these devise have a limited dynamic range, images captured in real world scenes with high dynamic ranges usually exhibit poor visibility and low contrast, which may make important image features lost or hard to tell by human viewers. In this paper, the efficient color image enhancement method is presented. Experimental result show that the proposed method yields better performance of color enhancement over the previous work for test color images.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.624-627
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• 1992

Mathematical modeling is majorly divided into three parts: the derivation of models, the fitting of models to data, and the simulation of data from models. This paper focuses on the parameter optimization which is necessary for the fitting of models to data. The method of simulated annealing(SA) is a technique that has recently attracted significant attention as suitable for optimization problem of very large scale. If the temperature is too high, then some of the structure created by the heuristic will be destroyed and unnecessary extra work will be done. If it is too low then solution is lost, similar to the case of a quenching cooling schedule in the SA phase. In this study, therfore, we propose a technique of determination of the starting temperature and cooling schedule for SA phase.

• 펄프종이기술
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• 제31권1호
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• pp.23-30
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• 1999

The effects of polyelectrolytes and enzyme, alone and in combination, were investigated in OCC recycling system. Four types of the polyelectrolytes based on acrylamide, cationic and anionic monomers were applied to the enzyme-treated KOCC stock to improve the strength and drainage properties of testliner. The polyelectrolytes used in this work were designed in terms of molecular weight and charge density. The water conditions used for recycling were also varied. The results showed that the hydrolytic action of enzyme gave reduced surface area and amorphous region of fiber, and as a result, the cationic polymer was lost apparently its flocculating power due to the reduced bonding site of fiber surface. When the hardness and conductivity of water had been controlled to the conditins of OCC paper mill, the application of amphoteric polyelectrolyte to the enzyme-treated recycled stock was the most effective with respect to the strength and drainage properties of testliner.

• 한국안전학회지
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• 제15권2호
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• pp.118-125
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• 2000

Construction industry has one of the worst occupational health and safety records amongst all other industries. In this study, we developed a method to compute the severity rate (SR) and measured SR values of apartment construction incidents. The two-year records (1996-1997) from database by the Korea Industrial Safety Corporation (KISCO) were used in the current study. To determine the severity rate (SR), the lost workdays (LW) and the number of injured workers and fatalities (NIW) as well as the number of accidents (NA) were considered. These results appear to indicate that the SR measurement we developed in this study is adequate to estimate the safety of apartment construction environment.

• 동력기계공학회지
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• 제11권4호
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• pp.12-17
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• 2007

Recently, many small and medium size diesel vehicles have been equipped with turbocharger and EGR system to get high performance and reduce $NO_x$ emissions but its application to heavy-duty diesel engine is not common yet. In this work, the simulation model for EURO-3 engine was developed using WAVE and then its performance and emission level were verified by comparing with experimental results. The possibility of current EURO-3 engine equipped with LPL EGR system which would be satisfied the EURO-5 regulation are examined. ESC 13 mode was chosen as the primary engine test mode, and the injection timing and fuel quantity were changed to compensate the lost engine performance caused by EGR. The system developed in this study shows that the current EURO-3 engine could satisfy EURO-5 $NO_x$ regulation by applying LPL EGR.

• 한국의사학회지
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• 제14권2호
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• pp.83-107
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• 2001

"Aheuichaulyo御醫撮要" was known to be published by Choi Jong-jun崔宗峻 in Korea高麗 Dynasty(A.D.1226), however its original copy is not available at the present. It was thought that Korean folk medicine and the remedies were recorded in this book, and these were recorded in "Euibangyoochui醫方類聚" published in Chosun朝鮮 dynasty(1445). "Euibangyoochui" is called a treasure-house of the knowledge of traditional oriental medicine which contains over 50,000 prescriptions and enormous amount of medical information. The restoration of "Aheuichaulyo" was possible during the process of establishment of data base work of "Euibangyoochui". "Aheuichaulyo" was restored as 132 chapters mainly from the related con tents of "Euibangyoochui" and partially from the contents of "Hyangyakjipsungbang鄕藥集成方" and "Boonmoononyukyihaebang分門瘟疫易解方" for the supplement.