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Byon, Sung-Kwang;Lee, Dong-Hyeong;Choi, Ha-Young
- Journal of the Korean Society of Manufacturing Process Engineers
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- v.16 no.3
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- pp.30-37
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- 2017
When a wheel profile of a train-tram is designed, both train and tram tracks should be considered. This study designed a wheel profile that enables high-speed driving(200km/h) on the train track and low speed driving on the tram track with multiple sharp curves. The study used the approximation optimization method to reduce cost and time, used the sequential quadratic programming method as the optimized algorithm, and the central composite design and response surface method as an approximate model. The optimized wheel shape based on this approximation optimization method reduced wear of the initial wheel showed a better performance in terms of derailment and lateral force.
https://doi.org/10.14775/ksmpe.2017.16.3.030 인용 PDF KSCI

Jung, C.Y.;Kim, Y.K.;Yoon, M.C.;Sim, S.B.;Ha, M.K.;Kim, K.H.
- Journal of Power System Engineering
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- v.5 no.2
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- pp.43-49
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- 2001
For machining auto-mobile cam, the developed biarcs-fitting method eliminates the ridge problems in conventional straight-line fitting approximation or single-arc fitting of curve tool path where it leaves ridges of tool marks on the machined surface of the workpiece. The powerful advantage of this biarc method is demonstrated by applying it to the numerically controlled machining of a curved cam profile, also verified by using a CNC simulating program for auto-mobile cam profile. As a result, this algorithm may be used in CNC milling and turning for cam profile machining with short block line.
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Lee S. H.;Chung Y. C.;Ju S. Y.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2002.02a
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- pp.19-25
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- 2002
Profile machining using cutter diameter compensation is widely used in die and mould manufacturing. Especially automotive die makers try to use 3D-profile machining for trimming or flange dies. But the technological requirements and implementation issues haven't been defined. In this paper we summarized the requirements and issues of 3D-profile machining. Approximation of input profiles into sequences of line and helical arc is the first major issue. The second major issue is removing cutter interference from the approximated curves holding z-values when the maximum cutter diameter is given. Keeping constant machining width, local machining, path linking problems and several detail technological requirements are also discussed.
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Park Tae Won
- Journal of Korean Academy of Oral and Maxillofacial Radiology
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- v.2 no.1
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- pp.23-27
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- 1972
A roentgenographic cephalometric study was made on the soft and hard tissue profile of Korean adults. The subject consisted of 52 males and 54 females from 17 to 22 years of age and with normal occlusion and acceptable profile. Twenty one landmarks were plotted and two oriented lines named SnH line and SnV line were drawn on the tracings of all cephalograms. The means and the standard deviations from the subjects were calculated in each measuring category and the means were compared with those of male and femal samples. The results were obtained as follow: 1. In depth and height, individual variations and sex differences of the lower facial profile were larger than the upper face. 2. The sex differences of upper facial profile were larger in height than depth. 3. The individual variations and sex differences of the top of nose were the smallest in all measuring points. 4. The thickness of the soft tissue of upper face and upper lip in male sample were larger than those of female, but the same matter were not found in mental region.
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