• 혜화의학회지
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• 제20권2호
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• pp.141-153
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• 2012

Nowadays, the humankind's lives are affluent enough and the modern medical cure systems have made the humans' lives much longer. In spite of the modern medical development, the chronic & regressive diseases are rapidly increasing ironically. In this regards, many countries endeavoring to rely on the traditional or CAM instead of Conventional and Modern Medicines. The late Steve Jobs who sought for the natural therapy for his pancreatic cancer was one representative example. Every countries are investing huge amount of money to become the leader in the CAM market. Moreover, by preoccupying the world-wide standards, each country is trying to grab the market monopoliy. In this thesis, I examined several coutries' CAM markets and their CAM development strategies. These strategies should be considered for the KTM development Strategy. Fortunately, KTM has doing the main role in the Korean CAM development strategy. But to become the world leader in CAM market, the governmental committee should be established and the Financial Investment and Aid Program should be followed. It is very important to obtain the world standards. To do so, the R&D capability should be enhanced also. The world trends in CAM should be scrutinized and the Government Agency - Scholartic Group - Research institute have to cooperate for the same target.

• 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.

• 한국공작기계학회논문집
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• 제11권3호
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• pp.1-8
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• 2002

This study is continuous with the study I (A Study on the Modeling) and the sample impeller of this study is defined by the modeling process of the exclusive CAD/CAM system developed in the study Ⅰ. And, this study describes a method for the 5-axis machining of impeller blades formed by ruled surface. Therefore, the exclusive CAD/CAM system is the software for modeling md machining of impeller blades. By using the machining method suggested in this study, we could manufacture impeller blades on 5-axis CNC machining center and the machined impeller was very agreeable to the designed impeller. Thus, theories proposed in this study can be very useful for the 5-axis machining of impeller blades.

• 연구논문집
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• 통권29호
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• pp.111-121
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• 1999

고속 Rapier loom에서 경사와 위사의 조직을 완성하여 직물을 제직하는 위입과 바듸침 기구는 캠구동 방식으로 동일축선 상에 4개의 캠이 설치되어 있다. 이들 캠들은 2개씩 한쌍을 이루면서 서로 공액운동을 수행하고 있으므로 정확한 설계에 의한 동기화운동이 필수적이다. 따라서 본 연구는 전체 거동의 파악을 위한 시스템의 정확한 해석과 컴퓨터 시뮬레이션을 통한 Rapier loom의 고속화를 목적으로, 위입과 바듸침기구의 곡선선정 및 캠의 회전에 따라 정확한 운동을 유도할 수 있도록 2가지 운동의 연관성은 물론 동시에 화면상에 구현할 수 있는 4개의 캠기구에 대한 시뮬레이션 프로그램을 개발하는 것이다.

• 한국분무공학회지
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• 제23권2호
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• pp.58-65
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• 2018

An analytic strategy to control the variable valve actuation applied to two intake valves (flow port intake valve and swirl port intake valve) was performed in this study. we considered the variation in phasing of intake valve profiles by using the Cam-in-Cam technology. The analytic model was implemented in the GT-Power simulation program and analyzed the result of regulated emissions such as, NOx and Soot, especially with IMEP characteristics. Namely, we meticulously investigated the sources of having effect on the amount of NOx and soot formation under the test conditions with retard timing of both flow port and swirl port intake valves for decreasing the opening duration by 35CAD. Also, we analyzed the effect of incylinder pressure and temperature with NOx variations and in-cylinder pressure and temperature on NOx variations and normalized turbulent intensity. Through this analysis, some useful results on the combustion and flow characteristics of the swirl port and flow port control of the intake valve were obtained by this study.

• 대한기계학회논문집A
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• 제26권8호
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• pp.1527-1533
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• 2002

When a mechanism transfers a motion to an intersected shaft, a cylindrical cam mechanism may be the best choice among the mechanisms. The cylindrical cam with a roller follower provides to transfer the motions to the intersect shafts simply without other connecting equipments of the intersect shafts. Typical example may be a roller-gear-cam mechanism. But the shape of the cam must be exactly defined in order to satisfy the conditions for the prescribed motion of the follower. This paper proposes a new method for the shape design of the cylindrical cams and also a CAD program is developed by using the proposed method. The relative velocity method calculates the relative velocity of the follower versus the cam at a center of roller, and then determines a contact point by using the geometric relationships and the kinematic constraints. The constraint used in the relative velocity method is that the relative velocity must be parallel to a common tangent line at the contact point of two independent bodies, i. e. the cam and the follower. Then, the shape of the cam is defined by the coordinate transformation of the trace of the contact points. Finally, this paper presents an example in order to prove the accuracy of the proposed methods in this paper and the application of the CAD program"CamDesign".

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.269-270
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• 2006

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 추계학술대회 논문집
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• pp.397-398
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• 2007

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.289-290
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• 2007

• 한국공작기계학회논문집
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• 제10권6호
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• pp.71-77
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• 2001

We have developed the exclusive CAD/CAM system for the machining of impeller blades. This study is about the mod-eling method for the effective machining of impeller blades farmed by ruled surface. As the impeller is consisted of boss part and blade part, the boss is modeled by rotational surface of hub curve on z-axis and the blade is described by ruled- surfaces between hub curve and shroud curve. This modeling process can be carried out on the software developed in this study. And, the developed software can describe the impeller as a solid model through interface with Solid-Works soul- ware. The developed software containing the interface method proposed in this study was very effective fur impeller modeling.