• 소성∙가공
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• 제7권3호
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• pp.233-245
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• 1998

A new approach has been proposed for the incremental analysis of the nonsteady state large deformation of planar anisotropic elastic-plastic sheet forming. A mathematical brief review of a constitutive law for the incremental deformation theory has been presented from flow theory using the minimum plastic work path for elastic-plastic material. Since the material embedded coordinate system(Lagrangian quantity) is used in the proposed theory the stress integration procedure is completely objective. A new return mapping algorithm has been also developed from the general midpoint rule so as to achieve numerically large strain increment by successive control of yield function residuals. Some numerical tests for the return mapping algorithm were performed using Barlat's six component anisotropic stress potential. Performance of the proposed algorithm was shown to be good and stable for a large strain increment, For planar anisotropic sheet forming updating algorithm of planar anisotropic axes has been newly proposed. In order to show the effectiveness and validity of the present formulation earing simulation for a cylindrical cup drawing and front fender stamping analysis are performed. From the results it has been shown that the present formulation can provide a good basis for analysis for analysis of elastic-plastic sheet metal forming processes.

• 박물관보존과학
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• 제13권
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• pp.71-80
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• 2012

소환이식은 주환(主環)만 있는 둥근 고리형의 이식이다. 본고에서는 백제 분묘에서 출토된 소환이식을 대상으로 과학적 분석을 통해 역사적 요소와의 연관성을 알아보고자 하였다. 부여 합정리 유적에서 출토된 백제이식 6점의 조형적인 특징과 재료학적 특성을 현미경과 X선형광분석기를 이용하여 분석하였으며 분석결과를 토대로 이식의 성분조성비와 제작기법을 유추하였다. 분석결과 백제 웅진기에서 사비기에 이르는 시기에는 금과 은의 합금재료를 생산하는 기술, 가열 압접 기술, 아말감도금 기술 등 다양한 기술이 금공품에 널리 적용되고 있었다는 것을 확인할 수 있었다. 이러한 분석 연구는 차후 백제 이식의 시대별·지역별 상관관계를 알아보는데 비교자료로 활용될 수 있을 것으로 본다.

• 대한가정학회지
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• 제18권1호
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• pp.47-52
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• 1980

In view of the nationel health, the health of women during their childbearing age is important. In Korean, several studies reported that incidence of anemic case was high among these group. The present study was conducted to investigate the dietetic life and dietetic problems among college women during their child-earing age. One hundred thirty seven college women (Age ranges 18.5 to 21.8) who lived in Gwangju area were randomly selected and were practiced dietary survey by three day records in November 1979. Also, hemoglobin level was determined. The result are summarized as follows; their diets were found to be lacking I total amounts of food it takes (878.6$\pm$266.9 gm) and in such foods as cereals, potatoes, beans, green and yellow vegetables, oils and fats and small fishes. but animal food intakes were sufficient in such foods as fishes, meats and eggs. The average calorie intake (1729.3$\pm$437.0kcal) was insufficient against R.D.A (2000kcal) and the daily energy expenditure (2024.7kcal). Lacking nutrients were Fe and Vitamin A these percentages of R.D.A. were 75.61% and 80.14% The mean body height (16.1$\pm$8.1cm) was higher tendency compared to other studies, but the mean body weight (49.8$\pm$4.1kg) was lighter. The average Hb level was 12.75$\pm$2.94gm%, and 13.64% of the subjects was anemic (12gm% below) The differences of each nutrient intake between the anemic and the healthy group not noted statistically significant.

• 한국의류산업학회지
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• 제3권2호
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• pp.105-114
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• 2001

The result of this study is on textile expressed in the costume of the Kazakh tribe, Kirgiz tribe, Tajik tribe. Basically the material of costume is fur, cotton flannel, felt, silk, cotton outwear, velvet cloth and beads, silver, earing, bracelet is used frequently. The tribes did embroider on the shoes, made of sheepskin or calfskin and collar, belt, button, pocket with the sketch of national trait. Eventually their cultures of costume seem to be very similar because of the resemblances in circumstance of nature, religion, custom of life but definitely they show conservatism in itself and independent culture. In the basic structure of traditional costume by races, there is no big difference. Then, in men, the trousers and the shirts of tunic type become the basic with the style which is convenient to act. And, to wear vest, or jacket, or chaban, over it makes a little difference. In women also, same structure shows with the form to wear vest or outwear, on the basis of one piece. But, in a small hat, head wear, color contrast, and decoration element etc., strict difference is showing. After all, they show very similar clothing life culture basically in natural environment, religion, and life habit etc., But, the discrimination is made in the detailed side. So, it can be said that they show the conservative nature of nationalities, and have preserved the unique identity of their own culture.

• 대한기계학회논문집
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• 제16권2호
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• pp.248-258
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• 1992

Three-dimensional rigid-plastic finite element formulation based on the membrane theory was described and a computer program for large deformation analysis was developed. In the formulation, normal and planar anisotropy of sheet material and rotation of the principal axes of anisotropy was taken into consideration. Sheet metal was assumed to be rigid-plastic material obeying Hill's quadratic yield criterion and its associated flow rule. Deep drawing process, as a preliminary test, for normal anisotropic material was analyzed in order to examine the validity of developed finite element program. The results were consistent with the existing finite element solutions or experimental data. The present study was mainly concerned with the influence of planar anisotropy on deformation behaviour. Finite element analysis and experiment were carried out for the whole process of deep drawing of planar anisotropic material. The computational and experimental results on the shape of ear, strain distribution and punch load were in good agreement.

• 복식
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• 제54권2호
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• pp.25-38
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• 2004

The purpose of this study is to analyze the fashion style in the drama 'sex and the city's character. Frist of all, mixing and matching style is one of Carrie's signiture styles, namely her ability to combine haute couture fashion with high street bargains and vintage buys to make ingenious ensambles. There are two main ways to go with this seperates look, the equal look, when tops are put with equally fabulous bottoms, and the unequal look, when fabulous tops go with less fabulous bottoms. Second, nowadays vintage style is one of fashion trend. The 'Sex and the city' has define trends when it comes to jewellery, it is the 'Carrie' nameplate and the Hermes's horseshoe necklaces, especially pearls were a big hit for vintage style. Also it takes a floral pattern and various hat makes a vintage style. Third, Sexual style shows a halter and sleeveless dress with long earing and splendid necklaces. And it takes a leopard pattern. Fourth, romantic style, one of the 'Sex and the city"s character's favourite garments is the dress. Its makes romantic moods a delicate with handbags, Manolo Blahnik's and Jimmy Choo's high hill shoes and corsages. The romantic pattern is floral and material is chiffon.ffon.

• 소성∙가공
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• 제17권3호
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• pp.170-181
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• 2008

The shape of rectangular cup used for Ni-MH(Nickel-coated Metal Hydrogen) battery for hybrid car looks quite simple, but the forming process of extruding and setting up process design are highly difficult. Furthermore, there are few concrete reports on the rectangular deep drawn cup as part of hybrid vehicles till now. In this study, process design for rectangular cup in the multi-stage deep drawing process is carried out, and FE analysis is also preformed based on the result of the process design. From the simulation result, some unexpected problems such as earing, wrinkling and excessive thickness changes of the intermediate blank occurred. To overcome these failures, a series of modification for punch shape in the forming process design are completed and applied. Considering the modified punch shape in the multi-stage deep drawing process, additional FE analysis is also carried out and the simulation result is verified in view of the deformed shape, thickness change and effective strain distribution. The result of FE analysis with the improved process design confirmed not only reducing thinning of wall and possibilities of failure but also improving the quality of drawing product through the modification of punch shape.

• 소성∙가공
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• 제29권5호
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• pp.272-281
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• 2020

As the thickness of mobile communication devices is getting thinner, the size of the internal parts is also getting smaller. Among them, the battery case requires a high-level deep drawing technique because it has a rectangular shape with a large aspect ratio. In this study, the initial blank shape was optimized to minimize earing in a multi-stage deep drawing process using an artificial neural network(ANN). There has been no reported case of applying artificial neural network technology to the initial blank optimal design for a square case with large aspect ratio. The training data for ANN were obtained though simulation, and the model reliability was verified by performing comparative study with regression model using random sample test and goodness-of-fit test. Finally, the optimal design of the initial blank shape was performed through the verified ANN model.

• 소성∙가공
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• 제24권2호
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• pp.115-120
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• 2015

Deep drawing of cylindrical cups is one of the most fundamental and important processes in sheet metal forming. Circular cups are widely used in industrial fields such as automobile and electronic appliances. Some of these cups are formed by a one-stage process, others such as battery cases and beverage cans are made by a multi-stage process. In the current study the multi-stage deep drawing of aluminum sheet metal is examined. The process consists of two deep drawing operations followed by two ironing operations. The press die, which can be used for the four-stage forming process, was manufactured allowing punch and die components to be easily changed for various experiments. The rolling direction of both the sheet and the drawn cups was always positioned toward the horizontal x-direction on the die face to minimize experimental errors during the progressive forming. The dimensional accuracy of the cylindrical cups formed at each stage and the earing defect due to the anisotropy of sheet were investigated. The influence of anisotropy on the thickness distribution was also examined. Both the thickness and the outer diameter of the cups were measured and compared for each set of experimental conditions. It was found that the dimensional accuracy of cups rapidly improves by employing the ironing process and also by increasing the amount of ironing.

• International journal of advanced smart convergence
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• 제5권4호
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• pp.21-25
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• 2016

Recent development in multi-channel surround is emerging in various formats to provide better stereoscopic and sound effects to consumers in recent broadcasting. The ability sound localize the sound sources in space is most considerable design factor on multi-channel surround system for human earing perception model. However, this paper propose the change of the sound localization according to the spacing of the speakers, which is not covered in the existing research focus on sound system design. Presently the sound system uses the position and number of the speakers to localize the sound. In the multi-channel surround environment, the proposed design uses the sound localization is caused by the directional characteristics of the speaker, the distance between the speakers and the distance between the listener and the speaker according to the directivity is required. The proposed design is simulated using virtual measurement with MATLAB simulation environment and performances are measured.