• 제목/요약/키워드: Uniform Process

검색결과 1,944건 처리시간 0.032초

An Invariance Principle of Uniform CLT for the Baker's Transformation

  • Jongsig Bae
    • Communications for Statistical Applications and Methods
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    • 제2권1호
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    • pp.194-200
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    • 1995
  • The baker's transformation is an ergodic transformation defined on the half open unit square. This paper considers the limiting begavior of the partial sum process of a martingale sequence constructed from the baker's transformation in the context of an invariance principle of a uniform central limit theorm.

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교복 브랜드화 시대의 여학생 교복 디자인에 관한 연구 (A Study on Design of Girls' School Uniform Since 1996)

  • 정은숙;서동애;이영화
    • 복식
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    • 제57권6호
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    • pp.17-31
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    • 2007
  • Fashion of one period is symbolic and figurative means of expression reflecting spirit, ideology, emotion and aesthetic values of that period. Designs of school uniforms fer girls also went through changes in various shapes along with changes in sociocultural and philosophical backgrounds in each period. Thus, in this study, in examining girls' school uniforms, how girls' school uniforms have evolved with what kind of design characteristics was observed along with process of historical changes, and investigation was made on realistic conditions of girls school uniforms since 1996 when active advancements in school uniform design were started. Also, through examination of girls' school uniform designs from homepage of large student uniform companies and catalogues, characteristics of girls' school uniforms after 1996 were observed. On the result, we could know that girl's school uniforms from 1996 to 2006 were designed in various forms compared to those of the past time and changing Arends of the era were reflected on the school uniform designs. Narrow waistline, shorter blouse, changes in the length of jacket and skirt showed that current school uniform designs pursue the fashionable and trendy designs unlike those of the past times that were uniform and strict. This study include organizing characteristics of girls' school uniform designs by each period, providing fundamental and realistic data for clothes manufacturing and marketing activities through analysis on designs of girls' school uniforms since 1996, and providing directions for future school uniform designs.

3D 가상착의 프로그램을 활용한 경상북도 한복근무복 디자인 (Gyeongsangbuk-do Hanbok Work Uniform Design Using 3D Virtual Dressing Program)

  • 임시은
    • 패션비즈니스
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    • 제27권4호
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    • pp.101-114
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    • 2023
  • This study aimed to create globally acceptable Hanbok-inspired work uniforms, by developing practical designs and providing useful resources for incorporating Hanbok characteristics into office attire. First, to establish the elements that the Hanbok work uniform should have, the definition and characteristics of service clothes and preferences for the process of modernization of traditional Hanbok were reviewed through a review of the preceding studies. For the Hanbok work uniform design, a total of 4 pieces, 2 for each male and female, were planned, a schematic diagram was created, and the design was modified after evaluation by fashion design experts. I made a pattern of the modified design with a CAD program, imported it into CLO 3D to produce a virtual costume, and confirmed the final design draft. Work uniform design has symbolism, functionality, and aesthetics as its characteristics. The functionality of the Hanbok work uniform designed in this study is suitable for the season, and it was designed to increase the efficiency of work when worn for a long time. The design was focused on the development of materials and patterns in consideration of comfort and activity. The esthetic nature of hanbok-inspired work clothes was intended to reveal details that could highlight the silhouette of the human body and reflect the beauty of hanbok.

모바일 스마트 기기 덮개 유리 순차이송형 성형기기의 가열시스템 최적화에 관한 연구 (Study on Optimization for Heating System of Sequential Feed-Type Mobile Smart Device Cover Glass Molding Machine)

  • 이준경
    • 한국기계가공학회지
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    • 제14권5호
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    • pp.75-80
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    • 2015
  • Nowadays, flat-shaped cover glass is widely used for mobile devices. However, for its good design and convenience of use, curved cover glass has been demanded. Thus, many companies have tried to produce curved cover glass through the shaving technique, but the production efficiency is very low. Therefore, the molding technique has been adopted to increase the efficiency for the curved-glass production system. For a glass-molding system, several heating blocks are installed, and the flat cover glass is sequentially heated and molded. The production time for the cover glass is very different depending on the heating conditions; thus, the prediction of the production time for different heating conditions should be needed. Therefore, in this study, the computations were performed with different heating conditions (uniform and non-uniform) in the present cover glass-molding machine. For uniform and non-uniform heating conditions, the simple correlation between the heating time and the heater capacity and the heating time to achieve higher durability can be suggested, respectively.

CAE를 활용한 박판 성형 부재의 면 품질 개선 (Improvement of Surface Quality of a Stamped Sheet Metal Member with CAE)

  • 김기풍;김세호;이동길;이기용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 춘계학술대회 논문집
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    • pp.318-321
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    • 2007
  • This paper is concerned with improvement of surface quality of a sheet metal member in the stamping process. The CAE procedure of the stamping process is utilized in order to investigate cause of surface troubles and to improve surface quality. A complicated shape of the sheet metal member can induce surface troubles such as wrinkles because of insufficient tensions force and non-uniform contact of a blank sheet with tools. This paper proposes two guidelines such as a change of tool shape and added draw-beads on the tool surface in order to increase tension forces and to induce uniform contact. The proposed guidelines are verified with the CAE of the stamping process. The CAE results show that the changed shape of tools and added draw-beads can reduce the amount of wrinkles and improve surface quality.

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원호 형상을 가지는 분말자석 단조성형공정에서의 예비성형체 설계 (Preform Design for the Sinter-forging Process of Arc-shaped Powdered Magnets)

  • 김승호;이충호;허훈
    • 소성∙가공
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    • 제8권2호
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    • pp.135-142
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    • 1999
  • Tube Process(TP) is one of the processes to produce permanent magnets. Advantage claimed for this process is that it can accmplish both densification and anisotropication in one step forming. This process is distinguished from other processes since it uses deformable tube for densification of powder magnets. TP has, however, difficulties in manufacturing permanent magnets from Nd-Fe-B green powder due to folding resulted from large height reduction and localized densification. Therefore, an adequate preform is necessary to reduce folding resulted from large height reduction and localized densification. Therefore, an adequate preform is necessary to reduce folding, lead magnets into almost desired final shape and get uniform densification. In this paper, preform design for TP is carried out without a deformable tube to investigate the behaviour of magnet sinter-forging. Preform design is accomplished to increase the effective magnet area with a near net shape and uniform densification.

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Effect of Process Variables on the Flash Butt Welding of High Strength Steel

  • Kim, Y.S.;Kang, M.J.
    • International Journal of Korean Welding Society
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    • 제3권2호
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    • pp.24-28
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    • 2003
  • This study was aimed to evaluate the quality of flash welded joints and optimize the welding process for flash butt welding of 780MPa grade high strength steel. And then the relationship between the welding process variables and the joint quality would be established. The effect of process variables between flashing and upsetting process was elucidated. Microstructure observation of the joint indicated that the decarburized band was mainly changed with upsetting process. Width of HAZ was also related to the upsetting conditions rather than the flashing conditions. Generally maximum hardness at HAZ was correlated with Ceq of steel and the empirical relationship was obtained to estimate the HAZ properties. Tensile elongation at the joint was usually decreased with increasing the initial clamping distance. Investigation of fracture surface after tensile and bending tests reveal that the origin of cracking at the joint was oxide inclusions composed of $SiO_2$, MnO, $Al_2O_3$, and/or FeO. The amount of inclusions was dependent on the composition ratio of Mn/Si in steel. If this ratio was above 4, the amount of inclusions was low and then the resistance to cracking at the joint was enough to maintain the joint performance. It was obtained that the flashing process influenced the conditions for the energy input to establish uniform or non­uniform molten layer, while the upsetting conditions influenced the joint strength. Heat input variable during flashing process was also discussed with the joint properties.

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An Experimental Study on Multiple ICP & Helicon Source for Oxidation in Semiconductor Process

  • Lee, Jin-Won;Na, Byoung-Keun;An, Sang-Hyuk;Chang, Hong-Young
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.271-271
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    • 2012
  • Many studies have been investigated on high density plasma source (Electron Cyclotron Resonance, Inductively Coupled Plasma, Helicon plasma) for large area source after It is announced that productivity of plasma process depends on plasma density. In this presentation, we will propose the new concept of the multiple source, which consists of a parallel connection of ICP sources and helicon plasma sources. For plasma uniformity, equivalent power (especially, equivalent current in ICP & Helicon) should distribute on each source. We design power feeding line as coaxial transmission line with same length of ground line in each source for equivalent power distribution. And we confirm the equivalent power distribution with simulation and experimental result. Based on basic study, we develop the plasma source for oxidation in semiconductor process. we will discuss the relationship between the processing parameters (With or WithOut magnet, operating pressure, input power ). In ICP, plasma density uniformity is uniform. In ICP with magnet (or Helicon) plasma density is not uniform. As a result, new design (magnet arrangement and gas distributor and etc..) are needed for uniform plasma density in ICP with magnet and Helicon.

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반용융 성형에서 강제 표면 냉각에 의한 유도 가열 방법에 관한 연구 (A Study on Induction Heating with Forced Surface Cooling in Semi-Solid Forming Process)

  • 박준홍;최영
    • 한국정밀공학회지
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    • 제22권1호
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    • pp.97-102
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    • 2005
  • The procedure of semi-solid forming is composed of heating a billet, forming, compression holding and ejecting step. There are several methods to heat a billet during semi-solid forming process such as electric heating and induction heating. Usually in semi-solid forming process, induction heating has been adopted to achieve more uniform temperature of semi-solid material. Although induction heating is better method than any others, however, there is still difference of temperature between internal part and surface part of semi-solid material. Worse yet, in case of high liquid fraction of semi-solid material, liquid of the billet will flow down though solid of the billet still remains, which is very difficult to handle. In the present study, induction heating of semi-solid material with compulsive surface cooling has been performed to obtain uniform distribution of temperature. Distribution of temperature of the billets was measured and compared with that of conventional distribution of temperature. By this new induction heating method, not only temperature over the whole billet become uniform, but also control of temperature is possible.

반용융 성형에서 간제 표면 냉각에 의한 유도 가열 방법에 관한 연구 (A Study on Induction Heating with Compulsive Surface Cooling in Semi-Solid Forming Process)

  • 최재찬;김병민;최영;박준홍
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.465-468
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    • 2000
  • The procedure of semi-solid forming is composed of heating a billet, forming, compression holding and ejecting step. There are several methods to heat a billet during semi-solid forming process such as electric heating and induction heating. Usually in semi-solid forming process, induction heating has been adopted to achieve more uniform temperature of semi-solid material. Although induction heating is better method than any others, however, there is still difference of temperature between internal part and surface part of semi-solid material. Worse yet, in case of high liquid fraction of semi-solid material, liquid of the billet will flow down though solid of the billet still remains, which is very difficult to handle. In the present study, induction heating of semi-solid material with compulsive surface cooling has been performed to obtain uniform distribution of temperature. Distribution of temperature of the billets was measured and compared with that of conventional distribution of temperature. By this new induction heating method, not only temperature over the whole billet become uniform, but also control of temperature is possible.

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