• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.42-45
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• 1997

Weldline movement of tailored blanks originates from two sources, primary and secondary. Primary movement occurs by geometrical reason, that is, just scratched lines on the no-weld blanks move during drawing to be fitted to geometrical change. Secondary movement is induced by the characteristics of tailored blanks itself. The primary movement was mainly dependent on the weldline location and not affected by the type of material. The secondary movement caused by laser welding and/or small strength difference in this study was not dominant compared with primary movement. The formability of tailored blanks always inferior to those of original blanks. This is due to the existence of hardened weld bead. The closer a weldline is to punch corner where drawing is most active, the worse its formability becomes. This is because the weldline prohibits the drawing process. It was confirmed by measuring diagonal length at the blank corner. The mode of fracture was changed form wall break to draw break when the weldling was close to the punch corner.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.88-91
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• 2011

Glass fiber drawing from a silica preform is one of the most important processes in optical fiber manufacturing. High purify silica preform of cylindrical shape is fed into the graphite furnace, and then a very thin glass fiber of 125 micron diameter is drawn from the softened and heated preform. A computational analysis is performed to investigate the heat transfer characteristics of preform heating and the glass fiber drawing in the furnace. In addition to the dominant radiative heating of preform by the heating element in the furnace, present analysis also includes the convective heat transport by the gas flowing around the preform that experiences neck-dawn profile and the freshly drawn glass fiber at high fiber drawing speed. The computational results present the effects of gas flow on the temperature of preform and glass fiber as well as the neck-down profile of preform.

• 대한기계학회논문집B
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• 제30권7호
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• pp.612-621
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• 2006

Drawing is a mechanical operation attenuating material thickness to an appropriate level for the next processing or end usage. When the input material has a form of bundle or bundles made of very thin and long shaped wires or fibers, this attenuation operation is called 'bundle drawing' or 'drafting'. Bundle drawing is being used widely in manufacturing micro sized wires or staple yarns. However, the bundle processed by this operation has more or less defects in the evenness of linear density. Such irregularities cause many problems not only for the product quality but also for the efficiency of the next successive processes. In this research a mathematical model for the dynamic behavior of the bundle fluid is to be set up on the basis of general physical laws containing physical variables, i.e. linear density and velocity as the dynamic state variables of the bundle fluid. The governing equations resulting from the modeling show that they appear in a slightly different form from what they do in a continuum fluid. Then, the governing equations system is simplified in a steady state and the bundle dynamics is simulated, showing that the shape of the velocity profiles depends on two model parameters. Experiments confirm that the model parameters are to be well adjusted to show a coincidence with the theoretical analysis. The higher the drawing ratio and drawing speed we, the more sensitive becomes the bundle flow to exogenous disturbances.

• 대한물리의학회지
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• 제8권4호
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• pp.513-523
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• 2013

PURPOSE: The purpose of this study was to investigate characteristics of the forced pulmonary function test effect and abdominal muscles activation by combined complex exercise with abdominal drawing-in maneuver training of chronic stroke patients. METHODS: 14 post stroke patients(10 males and 4 females) involved voluntary this study and we divided two groups into CEG(complex exercise group) and CEAG (complex exercise and abdominal drawing-in maneuver group).(n=7, per goup). Each groups implicated the 2 times, 30minute exercises for 6 weeks a day. The CEAG performed the complex exercise 15 minutes and 15 minutes of abdominal drawing-in maneuver. For data analysis, the mean and standard deviation were estimated; non-parametric independent t-test was carried out. RESULTS: According to the study, in the combined complex exercise with abdominal drawing-in maneuver group, FVC and activation of transversus abdominis/internal oblique were statistically significant difference compared to the complex exercise group. CONCLUSION: These results indicate that the combined complex with abdominal drawing-in maneuver was efficient in enhancing abdominal muscles activation and pulmonary function of chronic stroke patients.

• 폴리머
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• 제25권5호
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• pp.699-706
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• 2001

연신온도, 연신속도, 연신비 등 연신 조건에 따른 poly(ethylene 2,6-naphthalate) (PEN)의 배향상태 변화를 살펴보았다. 연신온도가 낮을수록 연신속도가 빠를수록 연신비에 따라 큰 복굴절 값을 보이며 FT-IR ATR dichroism 방법으로 구한 배향 특성도 복굴절의 실험결과를 뒷받침하였다. PEN을 $120^{\circ}C$에서 연신하면 무정형사슬 배향함수 ($f_a$)가 연신속도가 빠를수록 높은 값을 갖지만 $141^{\circ}C$에서 연신하면 반대로 연신속도가 빠를수록 낮은 값을 갖게 된다. 이러한 경향은 결정화 속도와 사슬 이완속도와의 관계로부터 설명이 가능하다. X-선 회절 실험 결과로부터 PEN의 naphthalene ring 구조가 필름표면에 평행하게 배열됨을 확인할 수 있었다.

• 한국기계가공학회지
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• 제20권5호
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• pp.96-102
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• 2021

Hexagonal bolt, nut, fittings, and high-pressure valves with special alloy play an important role in many industrial products. Numerical analysis was conducted to obtain data for designing a new drawing system. This study aims to predict the rolling force of the new drawing system compared to that of the established drawing system. The rolling force of the new drawing system was predicted using numerical analysis by assuming that it is in proportion to deformation. The rolling forces of Mo, Ti, and W were approximately 1.4, 0.5, and 2.5 times those of SUS. Because the values of ultimate strength of special alloys were more close to numerical analysis, the values of ultimate strength could be used to predict the rolling force of the new drawing system without numerical analysis in field.

• 한국정밀공학회지
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• 제24권9호
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• pp.110-118
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• 2007

ISB (Inner structured and bonded) panel with a pyramidal inner structure is actively developing to reduce the weight and to improve the crashworthiness of the material. The objective of this paper is to investigate into the variation of impact characteristics of ISB panels with a pyramidal inner structure according to joining types between skin sheets and inner structures. Several drop impact tests have been performed. In order to examine the impact characteristics at a drawing condition, drawing type of experimental set-up has been proposed. From the results of the experiments, the influence of joining types between skin sheets and the inner structures on the characteristics of the deformation, the energy absorption and the failure has been quantitatively examined. In addition, it has been shown that maximum load decreased and the maximum displacement increases as the joining type changes from the bonding to the welding. The results of the observation of the specimen have been shown that major wrinkles form in the minor crimping direction irrespective of the joining types. Through the comparison of the experimental results for bonding and welding specimens, it has been shown that the absorption energy of the bonded specimen is nearly 1.3-1.5 times of the welded specimen at the same displacement.

• 만화애니메이션 연구
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• 통권35호
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• pp.1-27
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• 2014

본 연구는 대안적인 교육모형을 연구하는 과정으로 뇌의 기능과 학습, 창작 기제를 고려한 교수법을 적용하면 애니메이션 드로잉능력이 효율적으로 신장될 것이라는 관점으로 이어지기 위한 연구의 선행분석 과정이다. 근래에 각 분야의 학문 연구들은 단순히 한 전공에 국한되는 것이 아니라 타 분야와의 융합적인 연구 활동을 통해 세분화 된 융합적 교육 콘텐츠를 생산해 내는 시도들을 하고 있다. 어떠한 분야 던지 복합적인 인문학적 경험 구조를 가지고 있기 때문이며 예술분야 또한 그러하다. 특히나 영상콘텐츠인 애니메이션 분야는 전문화된 영역이 세분화 되어 있기 때문에 드로잉 관련 교육만 보더라도 전문성에 필요한 항목을 명확히 하고 체계적인 교육방법을 개발할 필요성이 요구된다. 이에 본 연구는 애니메이션 교육방법의 전문적인 특성에 적합한 교육모형을 설계하기 위한 문헌 연구결과를 제시한다. 이에 애니메이션 분야의 교육에 가장 기초적인 능력을 연마할 수 있는 드로잉의 의미를 전공분야의 특성에 맞게 개념화하고 범주화하였다. 이후 재정립 된 드로잉의 개념과 범주를 통해 구성요소가 돌출되며 이는 후속 작업인 학습목표를 구체화하는 과정의 토대가 된다. 그에 대한 결과로 애니메이션 분야의 특성이 반영된 드로잉의 의미를 모션드로잉으로 정의하고 구성요소를 살펴보며, 뇌과학적 창의-학습 원리를 적용한 교육모형을 계획하기 위한 근거로 삼는다.

• 한국조경학회지
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• 제28권6호
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• pp.16-28
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• 2001

The purpose of this study is to arrange the terminology of the drawings in Chosun Dynasty, and to investigate the characteristics of drawings after the middle of Chos n Dynasty. This study is based on the and analysis of historic documents and drawings including drawings from China and Japan. In order to accomplish this, the drawings for the process of design were studied first, and the techniques of drawing were studied next in comparison with Japanese drawing techniques. Lastly, the technicians of drawing were studied. The results of this study were as follows; 1) Though the procedures of design Choson dynasty were not divided into planning, designing, construction and maintenance just like those of modern society, a variety of drawings in that time were used in each level. 2) The drawings in Choson Dynasty ere divided into Tohyong and Tosol, and mostly, those for design and construction were Tohy ng. 3) Based on the interpretation of Japanese drawings, several suggestions were presented to solve the questions of the drawing techniques for design and construction. 4) The technicians of drawing were the painters who were trained in a government organization in charge of royal paintings. In the future, research of this area should be continued in to deepen study on drawings as historical materials. This research provides meaningful of guidance in the analysis of historic drawing paintings.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1994년도 박판성형기술의 진보
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• pp.69-78
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• 1994

A rotating disk is introduced to be applied to the deep drawing press. Several characteristics are summarized to see the basics of deep drawing of sheet metal in terms of load-stroke relationship and formability. Many conventional drawing presses, which are mostly link-type presses, are also shown to be compared with the rotating disk-type press. Performances of the new press are kinematically analyzed it terms of load-main gear angle relationship, stroke-gear angle relationship, and slide velocity-gear angle relationship and they are compared with those of conventional types', e. g. crank press and so on. The comparison show kinematically better performance of rotating disk-type press than that of conventional ones. Also, the new press are proven to be one of the best press for mass production in terms of cycle time. Applicability of the rotating disk press to deep drawing and cold forging work is introduced. The new press is described in terms of economy such that the cost of new press would be much lower than those of conventional types'.