• 제목/요약/키워드: flow sheet

검색결과 524건 처리시간 0.026초

네오프렌 소재의 레이저 커팅기법 적용에 따른 물성 및 드레이프 형상 변화 연구 (A Study on Changes of Drape Shapes and Physical Properties by Applying Laser-Cutting Technique on Neoprene Materials)

  • 한유정;김종준
    • 패션비즈니스
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    • 제19권4호
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    • pp.109-119
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    • 2015
  • A wide variety of fashion materials focus on good drape property and softness. Among the recently emerging materials, Neoprene that consists of laminated knit on both sides of foamed neoprene sheet seeks a unique appearance that is considerably deviated from the current flow. Diverse processing methods for the newly released material heighten the value in function and beauty among trends of fashion materials by enhancing the appearance, touch and material property. Laser-cutting technique is one of the processing methods that is consistently used in the textile area. This study aimed to find the basic materials for applicability of laser-cutting technique to clothing goods after consideration of the changes in material property and drape shape, and to furthermore enforce different pattern conditions to Neoprene material, one of the newly attractive materials in the fashion area. In this study, we applied laser-cutting technique to Neoprene material sample under different conditions of pattern appearance, size and distance, based on current evaluation and theoretical background of Neoprene material, fashion trend and laser-cutting technique. Drape property can improve and the drape direction could also be controlled by a wide variety of laser-cutting techniques applied to Neoprene materials that have uniquely different appearances from most other textiles. This technique could be applied to the design for diversification of Neoprene clothing goods in the future.

경사진 기계평면시일의 변형거동 특성 해석 (Analysis characters of distortion of inclined mechanical face seal)

  • 조승현;고영배;김청균
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2001년도 제34회 추계학술대회 개최
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    • pp.341-349
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    • 2001
  • Heat distortion of the non-contacting mechanical face seal is affected by friction heat between primary seal and seal sheet. The fluid or gas in mechanical face seal maintains operating gap, cooling friction heat and lubricates at the face of seal. So we designed face of seal for inclined face. inclined face of seal improves fluid or gas flow at the face of seal and it increases circumferential velocity at outer radius of the seal so temperature of the seal is decreased by low heat transfer coefficient at there. In this paper, inclined face seal are analysed numerically using finite element method for proof improve inclined face seal performance. Angle of the incline face used for FEA is from 50$^{\circ}$to 90$^{\circ}$and for explaining the effects of inclined face in seal, we get temperature, face distortion, and stress in the seal with variable operating gap and rotating speeds. Result of analysis shows that angle of the incline face is 60$^{\circ}$come to good thermal distortion characteristics.

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차체용 강판의 온도에 따른 변형률 속도 민감도 연구 (A study on the strain rate sensitivity according to the temperature for steel sheets of an auto-body)

  • 이희종;송정한;조상순;김석봉;허훈;박성호
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2005년도 추계학술대회 논문집
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    • pp.148-151
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    • 2005
  • This paper is concerned with the thermo-mechanical behavior and temperature dependent strain rate sensitivity of steel sheet for an auto-body. In order to Identify the temperature dependent strain rate sensitivity of SPRC35R and SPRC45E, uniaxial tension tests are performed with the variation of the strain rates from 0.001/sec to 200/sec, and the variation of environmental temperatures from $-40^{\circ}C\;to\;200^{\circ}C$. The thermo-mechanical response at the quasi-static state is obtained with the static tensile test and at the intermediate strain rate is from the high speed tensile test. The experimental results show that the strain rate sensitivity increases at low temperature and it decreases at high temperature. It means that as the strain rate getting increasing, the variation of flow stress is more sensitive on the temperature. The results also indicates that the material properties of SPRC35R is more depend on the changes of strain rates and temperature than those of SPRC45E.

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GA 강판에 대한 $CO_2$ 수직용접자세의 특성에 관한 연구 (A study on the characteristics of vertical welding positions using GA steel sheet in the $CO_2$ welding)

  • 김재성;조용준;이경철;이보영
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2007년 추계학술발표대회 개요집
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    • pp.36-38
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    • 2007
  • The instability of the arc in the $CO_2$ arc welding affects the quality of the weld in the automotive industry. This paper evaluates the effects of the arc stability in $CO_2$ arc welding with respect to vertical welding positions. In this experiment, galva-annealed steel sheets(CA) were used as specimens, and these materials were welded by adopting new Cold Metal Transfer (CMT) process. For each sample, fillet joint welding trials were carried out using the same conditions. Each part of welding joints was welded with vertical-up, vertical-down position at $45^{\circ},\;90^{\circ}\;and\;135^{\circ}$ degrees. A high speed camera and a welding signal monitoring system were used for monitoring fluid-flow phenomena in weld pools and frequency measurements, respectively. Through this study, the welding position were found to be key factors mainly to influence the arc stability in $CO_2$ welding moreover and that the arc stability in the vertical-up welding position was observed to be more stable than the vertical-down welding position below $90^{\circ}$.

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Nd:YAG 레이저빔을 이용한 아연도금강판(SECC)과 쾌삭강봉(SUM24L)의 용접에 관한 연구 (Welding behavior between Zn-coated steel plate and free cutting carbon steel rod by Nd:YAG laser beam)

  • 노영태;김병철;김도훈;윤갑식
    • 한국레이저가공학회지
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    • 제4권3호
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    • pp.30-39
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    • 2001
  • This work was tamed out to apply a laser welding technique in joining between a Zn coated low carbon steel plate(SECC) and a free cutting carbon steel shaft(SUM24L) with or without W coating. Experiments were carried out and analysed by applying the FD(factorial design)method to obtain the optimum Laser welding condition. Optical microscopy, SEM, TEM and XRD analyses were performed in order to observe the microstructures in the fusion zone and the HAZ. Mechanical properties of the welded specimens were examined by microhardness test, tensile test and twist test. There was no flawed Zn in the fusion zone by EDS analysis. This means that during the welding process, Zn gas could be eliminated by appropriate shielding gas flow rate and butt welding gap. Ni coating itself did not influence on the tensile strength and hardness. However, twist bending strength and the weld depth of the Ni-coated free cutting carbon steel were lower as compared with those of the uncoated free cutting carbon steel. It was attributed to a lower absorbance of laser beam to the shin Ni surface. According to the results of the factorial design tests, the twist bending strength of welded specimens was primarily affected by pulse width, laser power, frequency and speed.

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장애인모델 TV광고에 대한 기호학적 분석 (Semiotics Approach to TV Advertisement of Disabled Model)

  • 이지석
    • 한국콘텐츠학회논문지
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    • 제15권3호
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    • pp.327-335
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    • 2015
  • 본 연구는 광고 커뮤니케이션 관점에서 장애인모델 TV광고에 대해 기호학적으로 분석하였다. 그레마스 기호사각형의 특징에 따라 장애인모델 TV광고에 대한 소비가치의 흐름은 보호적 가치에서 비-보호적 가치, 존재적 가치, 비-존재적 가치 순으로 움직이고 다시 보호적 가치로 ${\infty}$과 같은 형태로 이동하게 된다. 기호학적인 관점에서 네 편의 장애인모델 TV광고를 분석한 결과, SK텔레콤 TV광고(휠체어 농구편)는 존재적 가치, 아이폰4의 TV광고(연인편)는 비-보호적 가치, 삼성증권 TV광고(캠페인편)는 보호적 가치, 그리고 쏘나타 자동차 TV광고(쏘나타 터처블 뮤직시트)는 비-존재적 가치로 분석되었다.

기계식 프레스에 의한 자동차 시트 리클라이너의 고정밀 플레이트 홀더 개발(I) : FCF 공법 적용 (Development of High Precision Plate Holder in Automotive Seat Recliner by Mechanical Press(I) : Application of FCF Method)

  • 김병민;최홍석;장명진;배재호;이선봉;고대철
    • 한국정밀공학회지
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    • 제25권7호
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    • pp.55-63
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    • 2008
  • Fine blanking is a process of press shearing which makes it possible to produce the thick sheet metal of the finished surface and the close dimensional accuracy over the whole material thickness in the single blanking operation. In this paper, a plate holder of automotive seat recliner is manufactured by FCF(Flow Control Forming) method using the conventional mechanical press instead of the fine blanking press. Main processes for manufacturing of the plate holder by FCF method are embossing, half blanking and trimming processes. Optimal clearance, stripper force and counter force to increase the dimensional accuracy of the plate holder have been investigated by FE-analysis. As a result of FE-analysis, the clearance for both embossing and half blanking processes was -2%t and the forces of stripper and counter were 25ton and 15ton, respectively. After manufacturing the plate holder by FCF method, the measured dimensional characteristics have been compared with the required specifications as the final product. Although the dimensional accuracy of the plate holder manufactured by FCF method was a little inferior to that by fine blanking process, it was satisfactory in a general sense.

열간 조압연 공정에서 슬래브 측면부의 소성변형거동 예측 (Prediction of Plastic Deformation Behavior of the Side Surface of Slab during Hot Rough Rolling)

  • 정재환;이경훈;이선봉;이인규;이상호;김형진;이계영;김병민
    • 소성∙가공
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    • 제23권7호
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    • pp.425-430
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    • 2014
  • The aim of the current study was to predict the plastic deformation behavior of a heated slab during hot rough rolling. FE-simulations were performed to investigate the metal flow and to locate the position of surface material from the slab through the rough rolling and onto the strip, using a material point tracking technique. In addition, experimental hot rolling trials were conducted where artificial defects were impressed onto a heated slab in order to validate the FE-simulation results. The simulated results show the same tendency of deformation behavior as the experimental measurements. The movement of slab defects from the side surface towards the strip center is directly linked to the extent of lateral spread during the rolling.

Low-Temperature Plasma Enhanced Chemical Vapor Deposition Process for Growth of Graphene on Copper

  • ;장해규;채희엽
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.433-433
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    • 2013
  • Graphene, $sp^2$-hybridized 2-Dimension carbon material, has drawn enormous attention due to its desirable performance of excellent properties. Graphene can be applied for many electronic devices such as field-effect transistors (FETs), touch screen, solar cells. Furthermore, indium tin oxide (ITO) is commercially used and sets the standard for transparent electrode. However, ITO has certain limitations, such as increasing cost due to indium scarcity, instability in acid and basic environments, high surface roughness and brittle. Due to those reasons, graphene will be a perfect substitute as a transparent electrode. We report the graphene synthesized by inductive coupled plasma enhanced chemical vapor deposition (ICP-PECVD) process on Cu substrate. The growth was carried out using low temperature at $400^{\circ}C$ rather than typical chemical vapor deposition (CVD) process at $1,000^{\circ}C$ The low-temperature process has advantage of low cost and also low melting point materials will be available to synthesize graphene as substrate, but the drawback is low quality. To improve the quality, the factor affect the quality of graphene was be investigated by changing the plasma power, the flow rate of precursors, the scenario of precursors. Then, graphene film's quality was investigated with Raman spectroscopy and sheet resistance and optical emission spectroscopy.

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Three Dimensional Computer Modeling of Magnetospheric Substorm

  • Min, Kyoung-W.
    • Journal of Astronomy and Space Sciences
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    • 제6권1호
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    • pp.1-15
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    • 1989
  • Magnetospheic substorm in the magnetotail region is studied numerically by means of a three dimensional MHD code. The analytic solution for the quiet magnetotail is employed as an initial configuration. The localized solar wind is modeled to enter the simulation domain through the boundaries located in the magnetotail lobe region. As a result of the interaction between the solar wind and the magnetosphere, the magnetic field lines are stretched, and the plasma sheet becomes thinner and thinner. When the current driven resistivity is generated, magnetic reconnection is triggered by this resistivity. The resulting plasma jetting is found to be super-magnetosonic. Although the plasmoid formation and its tailward motion is not quite clear as in the two dimensional simulation, which is mainly because of the numerical model chosen for the present simulation, the rarification of the plasmas near the x-point is observed. Field aligned currents are observed in the late expansive stage of the magnetospheric substorm. These field aligned currents flow from the tail toward the ionosphere on the dawn side from the ionosphere to ward the tail on the dusk side, namely in the same sense of the region 1 current. As the field aligned currents develop, it is found that the cross tail current in the earth side midnight section of the magnetic x-point is reduced.

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