• Title/Summary/Keyword: Punch- through

Search Result 238, Processing Time 0.021 seconds

Analytical Study on I-beam of I-beam Grated Concrete slab (I 형강 격자 상판의 주부재 I형강에 대한 해석적 연구)

  • 박창규;김용곤;정영수
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2001.05a
    • /
    • pp.437-442
    • /
    • 2001
  • Recently, there have been increased much concerns about repair and rehabilitation works for aged concrete structures. In particular, it is known that due to repeated overburden vehicle there are significantly increasing number of aged concrete bridge slabs, which are strongly needed to construct and rehabilitate by innovative construction method. The objective of this research is to develop the new construction method of concrete slab in bridge structure, which can contribute to minimize the traffic congestion during the repair and rehabilitation works of aged concrete slab, and can also sufficiently assure the quality through the minimization of in-situ works at the site. I-beams with punch holes, which are substituted instead of main reinforcing steels in concrete slabs, will be manufactured in accordance with the specification in the factory. and will be preassembled into the Panel. After erecting the preassembled panels in the site, concrete will be poured into the slab panel. This research is to investigate physical properties of I-Beam with punch holes itself through static and fatigue test with rational numerical analysis Finally this research is to suggest reformed I-beam through the numerical analysis.

  • PDF

Fashion Satire in the Cartoon Magazine『Punch』 (카툰잡지『Punch』에 나타난 패션 풍자)

  • Ahn, Jinhyun;Chun, Jaehoon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.39 no.2
    • /
    • pp.204-216
    • /
    • 2015
  • Fashion is changing and evolving everyday with an influence from and over contemporary socio-cultural factors. Cartoons expressing the phenomena of times through exchanges of mutual effects with socio-cultural factors that result from functionality and media characteristics. This study examines how fashion provides a great correlation with society-culture expressed in cartoons. The research segment of this study was conducted with literature and case studies; in addition, the UK cartoon magazine "Punch" was selected for the case study. The research findings of the fashion satire expression in cartoon were divided into 2 cases. The first case is that fashion was used as an instrument to satirize socio-cultural phenomena in cartoons. Various fashion elements (hats, dresses, words on T-shirts) were used for satiric expressions and to express periodic images related to politics, economics, society and culture. It communicated factually or criticized noteworthy phenomenon or age changes through the symbolism of fashion. The second case is that fashion itself is the object of satire in a cartoon. It satirically described the blind following and destruction of stereotype as direct objects. Fashion satire appeared in cartoons regardless of a correlation with age. Each cartoon fashion satire had meaning in both humor and criticism for satirizing the age. This study shows that fashion symbolism for satire of the reality has been used as the instrument of expression and simultaneously expressed as the object of the critique as an image and phenomenon that reflects reality. This study has significance in that it examined expressive modes of fashion satire in cartoons that escape from separating fashion from cartoon as a different area.

Multiple Regression Analysis for Piercing Punch Profile Optimization to Prevent Tearing During Tee Pipe Burring (다중 회귀 분석을 활용한 Tee-Pipe 버링 공정에서 찢어짐 방지를 위한 피어싱 펀치 형상 최적 설계)

  • Lee, Y.S.;Kim, J.Y.;Kang, J.S.;Hong, S.
    • Transactions of Materials Processing
    • /
    • v.26 no.5
    • /
    • pp.271-276
    • /
    • 2017
  • A tee is the most common pipefitting used to combine or divide fluid flow. Tees can connect pipes of different diameters or change the direction of a pipe run. To manufacture tee type of stainless steel pipe, combinations of punch piercing and burr forming have been widely used in the industry. However, such method is considerably time consuming with regard to performing empirical work necessary to attain process conditions to prevent upper end tearing of the tee product and meet target tee height. Numerous experiments have shown that the piercing profile is the main cause of defects mentioned above. Furthermore, the mold design is formed through trial and error according to pipe diameters and changes in requirements. Thus, the objective of this study was to perform piercing and burring process analysis via finite element analysis using DYNAFORM to resolve problems mentioned above. An optimization design method was used to determine the piercing punch profile. Three radii of the piercing punch (i.e., large, small, and joined radii) were selected as design variables to minimize thinning of a tee pipe. Based on results of correlation and multiple regression analyses, we developed a predictive approximation model to satisfy requirements for both thickness reduction and target height. The new piercing punch profile was then applied to actual tee forming using the developed prediction equation. Model results were found to be in good agreement with experimental results.

A Study on Short Channel Effects of n Channel Polycrystalline Silicon Thin Film Transistor Fabricated at High Temperature (고온에서 제작된 n채널 다결정 실리콘 박막 트랜지스터의 단채널 효과 연구)

  • Lee, Jin-Min
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.24 no.5
    • /
    • pp.359-363
    • /
    • 2011
  • To integrate the sensor driver and logic circuits, fabricating down scaled transistors has been main issue. At this research, short channel effects were analyzed after n channel polycrystalline silicon thin film transistor was fabricated at high temperature. As a result, on current, on/off current ratio and transconductance were increased but threshold voltage, electron mobility and s-slope were reduced with a decrease of channel length. When carriers that develop at grain boundary in activated polycrystalline silicon have no gate biased, on current was increased with punch through by drain current. Also, due to BJT effect (parallel bipolar effect) that developed under region of channel by increase of gate voltage on current was rapidly increased.

Analysis of excess minority carrier and charge wish lifetimes in N-dirft region of NPT-IGBT (수명시간에 따른 NPT-IGBT의 N-drift 영역에서의 과잉소수 캐리어와 전하량 분석)

  • 류세환;이용국;안형근;한득영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.07a
    • /
    • pp.844-847
    • /
    • 2001
  • In this work, transient characteristics of the Non-Punch Through(NPT) Insulated Gate Bipolar Transistor(IGBT) has been studied. we has analyzed with lifetimes excess minority carrier injected into N-dirft, base region of IGBT's BJT part and accumulated charge of on-state which affected swiching characteristic. In this paper, excess minority carrier and charge distribution in active base region is expressed analytically. This analysis proposed optical trade-off between lifetimes and accumulated charge for decreasing switching losses because charge result in switching loss when device was tuned off.

  • PDF

Modeling of Anode Voltage Drop for PT-IGBT at Turn-off (턴-오프 시 PT-IGBT의 애노드 전압 강하 모델링)

  • Ryu, Se-Hwan;Lee, Ho-Kil;Ahn, Hyung-Keun;Han, Deuk-Young
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.21 no.1
    • /
    • pp.23-28
    • /
    • 2008
  • In this paper, transient characteristics of the Punch Through Insulated Gate Bipolar Transistor (PT-IGBT) have been studied. On the contrary to Non-Punch Through Insulated Gate Bipolar Transistor(NPT-IGBT), it has a buffer layer and reduces switching power loss. It has a simple drive circuit controlled by the gate voltage of the MOSFET and low on-state resistance of the bipolar junction transistor. The transient characteristics of the PT-IGBT have been analyzed analytically. Excess minority carrier and charge distribution in active base region, the rate of anode voltage with time are expressed analytically by adding the influence of buffer layer. The experimental data is obtained from manufacturer. The theoretical predictions of the analysis have been compared with the experimental data obtained from the measurement of a device(600 V, 15 A) and show good agreement.

Modeling transient characteristics of NPT IGBT including trun-on condition (턴 온 상태를 고려한 NPT IGBT의 과도 특성 모델링)

  • Ryu, Se-Hwan;Lee, Yong-Kuk;Ahn, Hyoung-Keun;Han, Deuk-Young
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.07a
    • /
    • pp.327-330
    • /
    • 2003
  • In this work, current-voltage characteristics with time of NPT(Non-PunchThrough) IGBT is proposed during turn-on and turn-off by using analytical method. From the results, power loss at turn-off dominates the total electrical loss with respect to that at turn-on. The results have been compared with those of PSPICE and show the identical trend of power loss with each other.

  • PDF

A Novel Design for High Voltage RC-GCTs (고전압 GCT(Gate Commutated Thyristor) 소자 설계)

  • Zhang, C.L.;Kim, S.C.;Kim, E.D.;Kim, H.W.;Seo, K.S.;Kim, N.K.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.07a
    • /
    • pp.312-315
    • /
    • 2003
  • Basic design of RC-GCTs (Reserve-Conducting Gate-Commutated Thyristors) by novel punch-through (PT) concept with 5,500v rated voltage is described here. A PT and NPT (non punch-through) concept for the same blocking voltage has been compared in detail. The simulation work indicates that GCT with such PT design exhibits that the forward breakdown voltage is 6,400V which is enough for supporting 5500V blocking. Additionally, the real IGCT turn-off in the mode of PNP transistor has been realized. However, the carrier extraction from N-base to gate terminal will be drastic slowly in terms of NPT structure except for the high on-state voltage drop.

  • PDF

A study on the breakdown characteristics of power p-n junction device using field limiting ring and side insulator wall (전계제한테와 측면 유리 절연막 사용한 전력용 p-n 접합 소자의 항복 특성 연구)

  • 허창수;추은상
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.45 no.3
    • /
    • pp.386-392
    • /
    • 1996
  • Zinc-Borosilicate is used as a side insulator wall to make high breakdown voltage with one Field Limiting Ring in a power p-n junction device in simulation. It is known that surface charge density can be yield at the interface of Zinc-Borosilicate glass / silicon system. When the glass is used as a side insulator wall, surface charge varied potential distribution and breakdown voltage is improved 1090 V under the same structure.The breakdown voltage under varying the surface charge density has a limit value. When the epitaxial thickness is varied, the position of FLR doesn't influence to the breakdown characteristic not only under non punch-through structure but also under punch-through structure. (author). 7 refs., 12 figs., 2 tabs.

  • PDF

Transient Analysis of PT-IGBT with Different Temperature (PT-IGBT의 온도에 따른 과도특성해석)

  • 이호길;류세환;이용국;안형근;한득영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2000.07a
    • /
    • pp.25-28
    • /
    • 2000
  • In this study, Transient Characteristics of the Punch-Through Insulated Gate Bipolar Transistor (PT-IGBT) has been studied. On the contraty to Non-Punch Through Insulated Gate Bipolar Transistor(NPT-IGBT), PT-IGBT has buffer layer It has a simple drive circuit controlled by the gate voltage of the MOSFET and the low on-state resistance of the bipolar junction transistor. In this paper, the transient characteristics with temperature of the PT-IGBT has been analyzed analytically. PT-IGBT is made to reduce switching power loss. Excess Minority carrier distribution inactive base region and base charge, the rate of voltage with time is expressed analytically to include buffer layer.

  • PDF