• 제목/요약/키워드: S-shape

검색결과 8,842건 처리시간 0.038초

스프링백 모드분류를 통한 박판 S-rail 성형공정의 형상정밀도 고찰 (Investigation of Shape Accuracy in the Forming of a Thin-walled S-rail with Classification of Springback Modes)

  • 정대근;김세호;김민석;이태길;김흥규
    • 소성∙가공
    • /
    • 제22권8호
    • /
    • pp.477-485
    • /
    • 2013
  • This paper aims to evaluate quantitatively the springback characteristics that evolve in the sheet metal forming of an S-rail in order to understand the reasons of shape inaccuracy and to find a remedy. The geometrical springback is classified into six modes: angle change of punch and die shoulders, wall curl, ridge curl, section twist, and axial twist. The measuring method for each springback mode is suggested and quantitative measurements were made to determine the tendency towards shape accuracy. Forming experiments were conducted with four types of steel sheets that have different tensile strengths, which were 340MPa, 440MPa, 590MPa and 780MPa, in order to evaluate the effect of the tensile strength and the bead shape on the springback behavior. Springback tendencies show that they are greatly affected by the tensile strength of the sheet and the shape of the tools. Almost all springback modes except the section twist and the axial twist show a linearly increasing trend as the tensile strength of the sheet increases. The results can be used as basic data for design and for compensation of the press die geometry when forming high strength steels which exhibit large amounts of springback.

$1920{\sim}1960$년대 제주시 주택의 변천에 관한 연구 (Transformations of Houses in Jeju City from 1920's to 1960's)

  • 김형남
    • 한국주거학회논문집
    • /
    • 제18권1호
    • /
    • pp.113-122
    • /
    • 2007
  • Houses in Jeju city are divided into separated types and combination types of household affairs space. Other special types are separated-kitchen type. Separated household affairs space type is mostly built. Separated household affairs space type were sitting room + Gopang separate type and separate sitting room type. Combination household affairs space type made from sitting room, kitchen, Gopang and Chabang(Dinning room) put together as space differentiation, also into classes sitting room + kitchen + Gopang + Chabang type, sitting room + kitchen + Chabang type, sitting room + kitchen + Gopang, sitting room + kitchen type by combination household cares space type. Separated-kitchen type was one of the special type from separated-kitchen type of traditional housing, and type with continuous. Houses in Jeju city were 3 kan type and 4 kan type. 4kan type was mostly built. ㅡ shape is kept as plan shaped of straight shape, and roof shape is showed as ㅡ shape gathering roof. ㅡ shape + part projection type talls part projecting type as happened in Gopang, and Chabang. Roof is gathering roof, and when it is showed ㄱ shape by Gopang, Chabang, and kitchen are projected. ㅡ shape + total projection shape is one of the room become totally projected by Gopang and Chabang, can be happen with small room or kitchen, and roof as gathering roof shaped with ㅡ shape, ㄱ shape, ㄷ shape, unsystematic ㄹ shape, and various shapes.

선형 배열 롤 셋 공정에서의 중간 형상 설계 (Design of intermediate shape in line array roll set (LARS) process)

  • 심도식;양동열;정성욱;한명수
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2009년도 춘계학술대회 논문집
    • /
    • pp.215-219
    • /
    • 2009
  • For the effective manufacture of doubly curved metal plates, a line array roll set (LARS) process is proposed. The suggested process utilizes a pair of upper and lower symmetric roll assemblies. In the process, the initial plate is progressed into the final shape in a stepwise or pathwise manner according to the basic principle of the incremental forming process. In this work, the intermediate shape which is closest to a final shape is proposed to fabricate the desired shape effectively in design of forming schedule. The intermediate shape has homogeneous curvature in a longitudinal and transverse direction so that it can be fabricated easily without complicated controls of rolls in the roll set. The method of approximation using genetic algorithm is proposed and applied to some actual ship hulls to evaluate the efficiency of the algorithm.

  • PDF

크로스 롤러가이드의 다단형상인발공정 패스 스케쥴에 관한 연구 (A Study on the Pass Schedule of Multi-Pas Shape Drawing Process for Cross Roller Guide)

  • 이태규;이찬주;이상곤;이선봉;김병민
    • 소성∙가공
    • /
    • 제18권7호
    • /
    • pp.550-555
    • /
    • 2009
  • In the multi-pass shape drawing process, the pass schedule that includes the determination of reduction ratio and intermediate die shape is very important. This study used the equal reduction, equal load, and electric field analysis method for pass schedule of the multi-pass shape drawing. The reduction ratio was calculated by the equal reduction and equal load method. And the intermediate die shape was determined by the result of the electric field analysis and the calculated reduction ratio. The proposed pass schedule method was applied to a shape drawing for producing cross roller guide. Finally, FE-analysis and shape drawing experiment were performed to verify the effectiveness of the proposed method.

Development of The New Shape Control Algorithm with The Strip Thickness Decoupling in Hot Strip Mill

  • Dukbum Shin;Kim, Jongcheol;Sangchul Won
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2001년도 ICCAS
    • /
    • pp.175.2-175
    • /
    • 2001
  • The strip profile and shape control is one of the most important technologies in Hot Rolling Mill System. Because the unbalance of strip´s shape and wave appearance between stands has a bad effect on Hot Rolling Mill System by making the inferior thickness, strip´s damage and so forth in factories. Many competition Plate Mill introduced shape control system, for example, pair cross-mill, work roll bender, which includes shape measuring instruments and shape control mathematical models. Shape meter, which is equipped for flatness, only does feedback control at the top of coil. And, for crown, we depend on initial setup value and there is no feedback control. Therefore we predict the shape of strip using rolling pressure, bender force and tension of inter-stand in ...

  • PDF

WLSD: A Perceptual Stimulus Model Based Shape Descriptor

  • Li, Jiatong;Zhao, Baojun;Tang, Linbo;Deng, Chenwei;Han, Lu;Wu, Jinghui
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제8권12호
    • /
    • pp.4513-4532
    • /
    • 2014
  • Motivated by the Weber's Law, this paper proposes an efficient and robust shape descriptor based on the perceptual stimulus model, called Weber's Law Shape Descriptor (WLSD). It is based on the theory that human perception of a pattern depends not only on the change of stimulus intensity, but also on the original stimulus intensity. Invariant to scale and rotation is the intrinsic properties of WLSD. As a global shape descriptor, WLSD has far lower computation complexity while is as discriminative as state-of-art shape descriptors. Experimental results demonstrate the strong capability of the proposed method in handling shape retrieval.

Various Men's Body Shapes and Drops for Developing Menswear Sizing Systems in the United States

  • HwangShin, Su-Jeong;Istook, Cynthia L.;Lee, Jin-Hee
    • 한국의류학회지
    • /
    • 제35권12호
    • /
    • pp.1454-1465
    • /
    • 2011
  • Menswear body types are often labeled on garments (to indicate how the garments are designed to fit) with indicators of a size category such as regular, portly, and stout, athletic, or big and tall. A drop (relationships between the chest and waist girths) is related to the fit of a tailored suit. However, current standards are not designed for various drops or body types. There is not enough information of categorizing men's body shapes for the apparel sizing systems. In this article, a set of men's data from SizeUSA sizing survey was analyzed to investigate men's body shapes and drops. Factor analysis and a cluster analysis method were used to categorize men's body shapes. In the results, twenty-five variables were selected through the factor analysis and found four factors: girth factor, height factor, torso girth factor, and slope degree factor. According to the factor and cluster analysis, various body shapes were found: Slim Shape (SS - tall ectomorphy), Heavy Shape (HS - athletic, big & tall, endomorphy and mesomorphy), Slant Inverted Triangle Shape (SITS - regular, slight ectomorphy and slight mesomorphy weight range from normal to slightly overweight), Short Round Top Shape (SRTS - portly and stout, endomorphy). Body shapes were related to fitting categories. SS and HS were related to big & tall fitting category. SITS was related to regular. SRTS was related to portly and stout. Shape 1 (31%) and Shape 2 (26%) were related to current big & tall category. Shape 3 (34%) were related to regular. Shape 4 (9%) were in portly and stout category. ASTM D 6240 standard was the only available standard that presented a regular fitting category. Various drops were found within a same chest size group; however, this study revealed great variances of drops by body shape.

원형빌렛으로부터 타원단면 및 S단면 가진제품의 압출가공의 DEFORM-3DTM에 의 한 비틀림 해석 비교 (A Comparision of the Twisting of Extrusion of Elliptical Shape with that of S shape from Round Billet by DEFORM-3DTM Software)

  • 김진훈;김한봉;진인태
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 1997년도 춘계학술대회논문집
    • /
    • pp.136-139
    • /
    • 1997
  • Applications of commercial software DEFORM-3DTM for 3-D simulation in extrusion process are developed for the analysis of twisting of extruded products. Because the elliptical shape has at least one line symmetry, the twisting is not occured during the extrusion. But, the results of extrusion simulation of the elliptical shape show that the twisted boundary of the die surface makes the material inside die surface rotate with the constant angular velocity. Otherwise, the simulation results of the S shaped product show that the twisting can be occured by the only 180$^{\circ}$rotation symmetry of S shape without no line symmetry and show that the angular velocity increases by the only 180$^{\circ}$rotation symmetry without no twisted die surface between on the die entrance section and on the die exit section. The results of the analysis show that the angular velocity of the extruded product changes with die length and friction condition.

  • PDF

중국의 모란문양 연구 (A Study of Chinese Peony Pattern)

  • 김재임;박춘순
    • 복식
    • /
    • 제44권
    • /
    • pp.57-75
    • /
    • 1999
  • The purpose of this study is to infer the shape and change as auspicious symbolic meaning and figures of a peony pattern. For this study. I analyzed the example of a peony pattern, which is traditional Chinese pattern appeared on a ceramic and textile. The results of this study are as following. First, a peony has particular title, such as 'the king of flowers' and 'the most beautiful woman in country and the smell in heaven' originated in a verse of a poet at Dang's Dynasty. It is reputed to be the best of all flowers, representing beauty, and a beauty. Second, the basic meaning of a peony pattern used as auspicious pattern is prosperity and it has various meanings of it's similar kind through several auspicious objects and combination. Also, it was used for the purpose of adequating the desire of man's blessing mentality. Third, four kinds of characteristics of a peony pattern are as following. 1) A peony pattern has similar shape with 'Bosanghwamoon', which was used as a pattern at formerly period of peony flowers. It was used as realistic shape gave vividness to the characteristic of peony on the shape of 'Bosanghwamoon'. 2) 8-petaled, unique leaves and veins were described in detail by vivid sketching shape of real peony flower. 3) Laying stress on the characteristics of peony flower, which is large and magnificent, several folds petals were described abundantly by exaggerated shape or a shape of big honeycomb. And unique leaves were described realistically on these. 4) It was also expressed peculiar characteristic of peony flower composed of several pieces by weakened design shape.

  • PDF

액주름포를 응용한 여성복 디자인 연구 (A Study on Women's Clothing Design Adapted from Acjurumpo)

  • 김월계
    • 복식문화연구
    • /
    • 제17권5호
    • /
    • pp.886-896
    • /
    • 2009
  • Acjurumpo is one of the most representatives daily outfit of Joseon Dynasty is a clothes which has a characteristic of having creases under the armhole and it has a lot of chance to use on modern clothes design. This study wants to provide a information on traditional clothes to the public and modernize traditional clothes by designing modern women clothes by adapting Acjurumpo, one of Joseon Dynasty's men' daily outfit which is not very well-known to publics as a link of traditional clothes modernization. Acjurumpo's characteristic is usually having a knife-shape collar and having two sup and one sup, but outside sup of having two sup was more common. There were tongsu, duri, as a example of shape of sleeve. For Mu the combinations were different from Acjurum starting with a shape of trapezoid, triangle to big Mu on a body of side line. For Gorum there were two pairs of long and short Gorum, two pairs of short Gorum or one pair of short or long Gorum. Slit of po was on both side or back. Acjurumpo which was adapted on modern clothes, it was usually used on Hanbok companies that used traditional shape or similar shape to design children' clothes. This study designed three summer one-piece and two winter jacket for women clothes adapting Acjurumpo. And it was designed by using modern material adapting Acjurumpo's characteristics, changing knife-shape collar, Acjurum, mu and Gorum. This study expects for popularization of many traditional clothes developed by modern design in future.

  • PDF