• Journal for History of Mathematics
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• v.19 no.3
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• pp.43-56
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• 2006

This paper aims to introduce a construction method for the 'Wooden Die for Drinking Game' and to find some geometrical structures and mathematics educational viewpoints. As the results, we get two methods which are eventually same with Figure 5 and Figure 6-3. We proved the ground that classical probability of this Die's each side showing up is one out of fourteen and introduced few other empirical probabilities with Table 1 to Table 3. Also, some Chinese characters were corrected and re-interpreted. In fact, 象人打鼻 changed to 衆人打鼻, and 醜物 is interpreted as 'ugly animal' such as frog, toad, earthworm or pine caterpillar.

• Transactions of Materials Processing
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• v.14 no.9 s.81
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• pp.772-778
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• 2005

This paper is concerned with the analysis of material flow characteristics of combined tube extrusion using pipe. The analysis in this paper concentrated on the evaluation of the design parameters for deformation patterns of tube forming, load characteristics, extruded length, and die pressure. The design factors such as punch nose radius, die corner radius, friction factor, and punch face angle are involved in the simulation. The combined tube extrusion is analyzed by using a commercial finite element code. This simulation makes use of pipe material and punch geometry on the basis of punch geometry recommended by International Cold Forging Group. Deformation patterns and its characteristics in combined forward and backward tube extrusion process were analyzed for forming loads with primary parameters, which are various punch nose radius relative to backward tube thickness. The results from the simulation show the flow modes of pipe workpiece and the die pressure at the contact surface between pipe workpiece and punch. The specific backward tube thickness and punch nose radius have an effect on extruded length in combined extrusion. The combined one step forward and backward extrusion is compared with the two step extrusion fer forming load and die pressure.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1085-1089
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• 2017

Juryeonggu is a cuboctahedral die that was used during the Silla period in ancient Korea. This cuboctahedral die consists of two different penal servitudes of 14 sides; however, its equal probability distribution enables it to be used as a die. In this paper, a precise cuboctahedral die, Juryeonggu, was manufactured, and its probability was measured through experiments. Next, the probability was verified through Multibody-dynamics (MBD) modeling and analysis, and the effect of the coefficient of friction on the probability distribution was studied.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.5
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• pp.14-18
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• 1990

본 논문은 당사에서 지금까지 개발한 성형 난이성 평가 CAE system에 관한 것으로 전체적인 system 구성, 기능 및 적용예등을 소개하기로 한다.

• Transactions of Materials Processing
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• v.14 no.1 s.73
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• pp.57-64
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• 2005

This study deals with the cold forging process design for shaft in the main part of automobile motors with rectangular deep groove. In forging process, the accuracy and die lift is very important because it have influence on reduction of the production cost and the increase of the production rate. Therefore, it is necessary to develop the manufacturing process of shaft by cold forging., process variables are the cropped face angle of billet and the eccentric load of punch. The former is derived from cropping test, the latter is occurred by clearance between container and preform. Also, grooved preform select the process variable for decrease in punch deflection. We investigate that a deflection of punch and a deformation of preform to every process variables. Through this investigation, we suggest the optimal preform and process design, expect to be improved the tool life in forging process.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1474-1486
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• 1990

The frictional characteristics of galvanized sheet steels(GA, EG, EGF, EGN) for automobiles were studied and compared with that of cold rolled sheet steel. A draw bead tester which simulates metal flow through a draw bead in stamping die face was used to measure coefficients of friction of galvanized sheet steels for four kinds of lubricants. Stamping formability of galvanized sheet steels for quarter outer panel was examined. The results show that stamping formability and friction characteristics were mainly influenced by the nature of zinc coating, surface roughness and micro hardness of coated layer, and proved to be very sensitive to the lubricant used.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.54-67
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• 1993

This study is to investigate the stress and stress degree in mothers of autistic children. In order to obtain data for planning nursing strategies for mothers of autistic children The assessment tool for the stress was constructed through reviewing literatures on the stress and gathering the stress items by nonstructed face to face interviewing 14 mothers of autistic children The stress tool consists of 74 items each with five point rating scale A data collection was made front 160 mothers of autistic children from 11 institutions for autistic children in Seoul and Kyung-Ki province. The reliability coefficients by Cronbach's a test was 0.94 for the stress scale. The results are as follows : 1) The mean of stress is 3.19, in the area of the etiology, prognosis and the treatment-education, with cause of the treatment the edeucatlon and the prognosis of child's handicap. The mean of stress is 2.85 In the area of the negative of mother's self image, 2.45 in the area of the mother's ordinary life. The mean of stress was 2.05, lowest in the family and social relationship 2) The mean score for the total was 2.62 points. The items with highest stress score were 'All autistic child has not been understood by the society', 'If we die, 1'm afraid that this child will not be cared by someone', 'There is no institution that the child get the schoolibg', etc The stress item with the lowest mean score were 'Keep away the child from husband', 'Being divorced by husband', etc. 3) An analysis of relationship of stress degree to general characteristic shows a statisically significants difference in the number of children in the family and the cognition of the seventy of the child problem