• International Journal of Precision Engineering and Manufacturing
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• v.2 no.1
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• pp.87-93
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• 2001

A reliable analytic model that determines the exit cross sectional shape a workpiece(material) in round-oval (oroval-round) pass sequence has been developed. The exit cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groovw to the roll axis direction. The requirements placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by not rod rolling experiment with the roll gap and specimen size changed. The exit cross sectional shape and area of the workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. We found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.659-664
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• 2000

In this paper, We have discussed on the modeling of machined outer geometry which was established for the case of round shape machining, also the effects of externally machined profile are analyzed and its modeling realiability was verified by the experiments of roundness testing, especially in lathe operation. In this study, we established harmonic geometric model with the parameter harmonic function. In general, we can calculate the theoretical roundness profile with arbitrary multilobe parameter. But in real experiments, only 2-5 lobe profile was frequently measured. the most frequently ones are 3 and 5 lobe profile in experiments. With this results, we can predict that these results may be applies to round shape machining such as turning, drilling, boring, ball screw and cylindrical grinding operation in bearing and shaft making operation with the same method. In this study, simulation and experimental work were performed to show the profile behaviors. we can apply these new modeling method in real process for the prediction of part profile behaviors machined such as in round shape machining operation.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1024-1026
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• 2003

This paper deals with the characteristic analysis of round shape core of transformer compared with conventional EI core transformer. The round shape has specific configuration to reduce leakage magnetic flux. Characteristics such as B-H characteristic curve and in-rush current, etc. are compared.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.55-61
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• 2000

In this paper we have discussed on the characteristics and modeling of machined geometry which was established for the case of round shape machining also the effects of externally machined profile are analyzed and its modeling realia-bility was verified by the experiments of roundness testing especially in lathe operation. In this study we established a harmonic geometric model with the parameter harmonic function. In general we can calculate the theoretical roundness profile with an arbitrary multilobe parameter. But in real experiments only 2-5 lobe profile was frequently measured, The most frequently measured ones are 3 and 5 lobe profile in experiments. With these results we can predict that these results may be applied to round shape machining such as turning drilling boring ball screw and cylindrical grinding operation in bearing and shaft making operation with the same method. in this study simulation and experimental work were performed to show the profile behaviors. we can apply these new modeling methods in real process for the predic-tion of part profile behaviors machined such as in round shape machining operation.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.5
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• pp.842-852
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• 1995

The purpose of this study was to provide fundamental data of characterizing for age group of obese women's body shape. The subjects were 132 obese women, age of 20~59. The criteria of obestity based on Vervaeck index ($\geq$92.3), Rohrer index ($\geq$ 1.6), and bust girth ($\geq$90 cm). Thirty eight measurement items were used for F-test. Forty two transformed variables (including 4 additional variables) were used for cluster analysis The results were as follows: 1. Characteristics for age group were described that 20's was narrow shoulder, flesh contoured shape in upper body. 30's was rounded upper back, 40's was the slightest fatty shape, and 50's was the fattest round shape among four age groups. 2. Four types of obese women's body shape were classified by cluster analysis. Body shape of type 1 was fatty abdomen, and rounded upper back in 50's mainly. Body shape of type 2 was slightly fatty. Body shape of type 3 was round shape. Body shape of type 4 was the smallest girth in the obese women in 40's mainly.

• Transactions of Materials Processing
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• v.18 no.4
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• pp.323-328
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• 2009

The prediction of drawing load is very important in the drawing process. However, it is not easy to calculate the drawing load for the shape drawing process through a theoretical model because of a complex arbitrary final cross section shape. The purpose of this study is to predict drawing load in shape drawing process. The cross section of product is divided with small angle as much as similar with fan-shape. The drawing load of each section was calculated by theoretical model of round to round drawing process. And the shape drawing load was determined by summation of drawing load of each section. The effectiveness of the proposed method was verified through the FE analysis and shape drawing experiment. It had a good agreement between proposed method, FE analysis and experiment within about 3% errors.

• Journal of Conservation Science
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• v.25 no.1
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• pp.1-16
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• 2009

Jeollabuk-do is bounded by the sea, and Mahan Baekje culture have been established around a wide plain. Also, in southeastern, it was closed by Gaya kingdom where iron culture was prosperous at that time, a variety of the handles of swords with round pommel is excavated at present. The handles of swords with round pommel is the best amount of excavated objects among the swords with round pommel and producted object for the time. It supposes them to become the foundation of making the decorated swords with round pommel. But, the handles of swords with round pommel that don't have a pattern in handle is indifferent to study because the production method is simple in spite of that the value of archaeological data is sufficient. Therefore, in this study, it examined changed production techniques with the change of times concerning the handles of swords with round pommel of Mahan Baekje Gaya period(before 6C) excavated from Jeollabukdo through using X-rays in order to clarify a variety of production techniques of the handles of swords with round pommel correctly in accordance with a period of production and excavated place. As a result, identified production techniques using X-rays of the handles of swords with round pommel excavated around remains of Mahan Baekje Gaya period shows that production progress improved in order of all-in-one shape, hammer welding shape of the handle of round pommel, and two in body formation in accordance with age. Especially, in two in body shape, it products the handle of round pommel separately, after that it welds the handle of swords and then links the sword blade like a riveting or bottleneck and so on. Despite of improved hammer welding technique, the reason why it didn't utilize is it regards as inlay or gilt will be damaged. And it is judged by using riveting or bottleneck. Also, it appears to techniques of metal craft such as decoration of the handle, decoration of point of sword, inlay, and silver-plating in the period of appearing two in body shape. As clarifying correctly, it provides fundamental database of scientific research about a study of production techniques of handle of swords with round pommel.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.343-349
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• 1998

A modeling of machined geometry and cutting force was proposed for the case of round shape machining, and the effects of internally machined profile are analyzed and its realiability was verified by the experiments of roundness tester, especially in boring operation in lathe. Also, harmonic cutting force model was proposed with the parameter of specific cutting force, chip width and chip thickness, and in this study, we can see that bored workpiece profile was also mapped into cutting force signal with this model. In general, we can calculated the theoretical lobe profile with arbitrary multilobe. But in real experiments, the most frequently measured numbers are 3 and 5 lobe profile in experiments. With this results, we can predict that these results may be applied to round shape machining such as drilling, boring, ball screw and internal grinding operation with the same method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.04a
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• pp.251-255
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• 1991

The primary objectives of the rolling process are to reduce the cross section of the incoming material while improving its properties and to obtain the desired section at the exit from the rolls. Many engineering metals, suchas aluminium alloys, copper alloys, and steels are often cast intoingots and are then further processed byhot rolling into blooms, slabs, and billets, which are subsequently rolled into other products such as plate, sheet, tube, rod, bar, and structural shapes. In shape rolling a round or square bar is rolled in several passes into various shapes. During eachpass, the bar elongates as well as spreads. Thus, a very complex three-dimensional metal flow takes place. In this paper TASKS results for the simulation of a 7 pass square-to-round shape rolling are presented. The results are verified by comparing it with experimental results from a previous study conducted at the Battelle Columbus Labs

• Journal of the Korean Society of Costume
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• v.35
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• pp.305-324
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• 1997

The purpose of this study was to examine aesthetic effects of face type and necklines of one piece dress one of details in clothes on visual evaluation. For this study two set of stages were processed. At first stage data were collected from female college students in Kwang Ju.Chonnam. Subjects between the aged of 18-26 were took pictured of their faces then they were classified into 7 groups That is egg ob-long round square inverted triangle triangle and diamond shapes. At second stage two sets of experimental design were utilized based on the classified face types. A set of design was 5$\times$4 design which involved 5 levels (egg oblong round inverted triangle and diamong shape) of face type and 4 levels(round boat vee and square neckline) of basic neckline. Another set of de-sign also was 5$\times$4 design which involved 5 levels of face type and 4 levels of modified neckline. As experimental treatment the stimulus materials and questionnaires were employed. The qustionnaires were consisted of visual evaluations on the stimulus materials by using semantic differential scale,. The experiments were proceeded through 2 week by 30 subjects composed of gaduate students and staffs in some departments of Clothing and Textiles at college. Data were analyzed by Frequencies Mean Factor Analysis TTest ANOVA and Ducan's Multiple Range Test. The major results were as followed: 1. There were significant aesthetic effects of face type on visual evaluations, Especially egg and inverted triangle shape among the face types were evaluated more aesthetic than the other face shapes. 2. There were signifiant aesthetic effects of the neckline types on visual evaluations, Es-pecially vee neckline among necklines were more aesthetic than the other necklines,. 3. As compared with the basic neckline types and the modified neckline types the modified necklines were assessed more aes-thetically than the basic necklines. 4, The face type and he neckline type were influenced interactively on visual evauations Specifically it showed that oblong round and diamond shape of face type were matched to vee neckline more than the other necklines, Also it showed that the egg and inverted tri-angle shape wee matched to round vee and squre neckline more than boat neckline.