• 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.

• 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.

• 대한심미치과학회지
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• 제13권1호
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• pp.31-39
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• 2004

For the prosthodontic results which are compatible with esthetics to be fulfilled, the first prerequisite would be periodontal intervention and stability, the second one may be functional competency and the ultimate goal should be ascribed to esthetic considerations. Other words, esthetic dentistry is a whole entity which encompasses the biological stability of the periodontium, physical accuracy of the prosthodontic structure and finally, the beauty which can be found in natural dentition. It also implies the harmonized lip line which reveals the well-balanced tooth morphology and health gum profiles (Red-White Esthetics). Largely, there lie some differences in the input system of the 3-dimentional data from the prepared abutments between respective computer-assisted systems available now. But the manufacturing systems (CAM) are very similar between them, to say, comprise numeric control systems with whole 3-dimensional milling units according to the restorations to be made. Now the author is going to present CAD/CAM Zirconia All Ceramic Restoration on the topics for the Red-White Esthetics, periodontal control and maintenance, treatment for the discolored teeth, post & core build-up works for the devitalized teeth, characteristics of the Zirconium oxide All Ceramics, fabrication procedures, clinical considerations and its application to diverse clinical situations.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.245-250
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• 1999

In order to design micro-fan appropriately, flow chacracteristics and mechanics should be carefully considered. The present work concerns with design procedure for a micro-fan using NACA(National Advisory Committee for Aeronautics) airfoil series. The generation of fan profiles is carried out automatically by defining related parameters, which is also converted to CAD/CAM data automatically. The optimal parting surface for the mold of micro-fan is also calculated by analyzing the geometric data numerically. As a consequence, the high capacity micro-fan can be developed successfully with a high-quality and an improved efficiency.

• 구강회복응용과학지
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• 제31권4호
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• pp.364-370
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• 2015

최근 구치부 부분 무치악 환자의 임플란트 보철 수복은 기능적뿐만 아니라 심미적으로도 환자의 만족을 이끌어내야 하는 과제를 안고 있다. 이렇게 환자의 요구가 높아지면서 상실된 자연치아와 유사한 형태의 임플란트 보철을 사용한 구강회복이 보철수복의 중요한 이슈가 되고 있다. 이를 위해서는 기성 지대주 보다는 더 넓은 customized CAD/CAM 지대주를 사용함으로써 자연스러운 출현윤곽을 재현할 수 있다. 넓은 지대주를 지지해주기 위해서는 충분한 폭과 높이를 가지는 각화치은이 존재해야 하는데, 만약 긴 치아상실기간이나 골이식술 등으로 인해 임플란트 주위에 각화치은이 부족한 경우에는 연조직 증대술을 시행하는 것이 추천된다. 이러한 과정을 통해 심미적이고 기능적인 임플란트 보철 제작이 가능하며 구강위생관리를 용이하게 하고 향후 임플란트 주위염의 발생 가능성을 감소시킨다. 본 증례는 구치부 부분 무치악 환자에서 골이식술, 상악동 이식술, 임플란트 식립술 및 연조직 이식술을 사용하여 부족한 치조골과 각화치은 및 협측전정을 회복하였으며, customized CAD/CAM 지대주와 지르코니아 보철물을 이용하여 수복한 증례로 주기적인 내원 및 검사를 통해 기능적, 심미적으로 만족할만한 결과를 얻었기에 이 사례를 보고하고자 한다.

• 한국기계가공학회지
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• 제18권8호
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• pp.91-97
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• 2019

A method for generating 3D solid models and drawings for a rotor in the steam turbine is proposed. One of the most important design steps is generating the drawing for manufacturing it. This step is a very routine and time-consuming job because each drawing is composed of several kinds of views and many dimensions. To achieve automation for this activity, rotor profiles are composed of 2D entity groups with attributes. Based on this, the improved design process is developed as follows. First, the rotor profiles can be selected by searching for 2D entity groups using the related attributes. Second, the profiles are connected sequentially so that an entire rotor profile is determined. The completed profile is used to generate 2D drawings automatically, especially views, dimensions, and 3D models. The proposed method is implemented using a commercial CAD/CAM system, Unigraphics, and API functions written in C-language and applied to the rotor of steam turbines. Some illustrative examples are provided to show the effectiveness of the proposed method.

• 대한기계학회논문집A
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• 제37권1호
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• pp.55-60
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• 2013

컴파운더 보우는 리커브 보우와 비교하여 케이블 및 캠 풀리로 구성되는 지레시스템을 사용하여, 궁사가 보우를 최대 위치로 당기기 위해 필요로 하는 힘을 줄이는 동시에 더 많은 에너지를 축적할 수 있도록 해준다. 지금까지 컴파운더 보우의 효율 및 성능을 향상시키기 위해 경험적인 방법에 기초하여 많은 특허가 제안되었지만, 해석적인 방법에 대한 연구는 별로 없었다. 그러므로 본 연구에서는 컴파운더 보우 지레 시스템의 기구학적인 해석을 위한 방법을 제안하여 지레시스템의 캠 형상 및 보우 날개의 재질변화에 따른 효과를 설계자가 쉽게 예측할 수 있도록 하고자 한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.409-412
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• 2004

In this paper, an integrated automation system of pattern design and $CO_2$ laser cutting for diving suits is presented. Pattern design includes grading which creates a full-size range from a base pattern. Tool path for laser cutting from the patterns is generated in G-code format. $CO_2$ Laser cutting machine is developed to help cut the patterns with accuracy and speed. Aluminum profiles, ball screws, and stepping motors are engaged into the machine as frame structure, transfer unit, and driving devices respectively. The developed system is tested in dry suit cutting, convincing it can be readily introduced in driving suits manufacturing with respect to cost and efficiency.

• 대한기계학회논문집
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• 제17권2호
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• pp.407-415
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• 1993

This report presents an automatic measurement method of 3-dimensional profiles of free-formed surfaces, by using a touch a touch-trigger contact probe along with a conventional coordinate measuring machine. The method proceeds in three steps; The surface profile under consideration is traced by the probe in an automatic manner, and then its measured data is compensated by considering the actual probe radius. Finally the compensated data is rearranged in the form suitable for the further processings of CAD/CAM applications. Some experimental results are discussed to verify the validity of the method suggested in this study.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1997년도 제26회 추계학술대회
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• pp.225-231
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• 1997

This paper reports on the theoretical study of the delivery pressure ripples of a positive displacement vane pump which is widely used for automobile power steering. Pressure ripples occur due to the flow tipples which induced cam ring profiles and reverse flow from the delivery ports. In this paper, the mathematical model for analyzing the pressure ripples has been presented, and set of the differential equationshave been solved using the Runge-Kutta method. As the results of analysis, instant ideal flow ripples, internal pressure, delivery pressure ripples, and delivery flow ripples have been presented. Internal pressure was related to delivery pressure variations, and amplitude of pressure tipples was increased with rotational speed and delivery pressure.