• Title, Summary, Keyword: junction box

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A Study on the Buckling Behavior of the Web of Box Girders (상자형 복부판의 좌굴 거동에 관한 연구)

  • Lee, Sang Woo;Kwon, Young Bong
    • Journal of Korean Society of Steel Construction
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    • v.9 no.1
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    • pp.37-49
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    • 1997
  • The buckling behavior of the web of steel girders are largely dependent on the size and the location of stiffeners and the restraining effect of top and bottom flanges. Elastic and inelastic buckling analyses based or the Spline Finite Strip Method were executed to study the stiffening effect of the longitudinal stiffener on the web of box girders and to find how the top and bottom flanges had effects on the web, where geometric boundary conditions were limited by both hinged, both fixed and the flange sections. The basic assumption for the longitudinal end boundary conditions was that the vertical stiffeners had the rigidity enough to force nil deflection line on the web panel so that the junction line between web and vertical stiffener was assumed to be hinged boundary conditions. The provisions on the longitudinal stiffener of the plate and box girders of the Korean Standard Highway Bridge Specifications(1995) and AASHTO Specifications(1994 LRFD) were compared with the results obtained numerically for the various longitudinal stiffener size of box girders. Simple equations and design curves for the longitudinal stiffener of the web were proposed for the practical use.

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A discretization method of the three-dimensional poisson's equation with excellent convergence characteristics (우수한 수렴특성을 갖는 3차원 포아송 방정식의 이산화 방법)

  • 김태한;이은구;김철성
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.8
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    • pp.15-25
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    • 1997
  • The integration method of carier concentrations to redcue the discretization error of th box integratio method used in the discretization of the three-dimensional poisson's equation is presented. The carrier concentration is approximated in the closed form as an exponential function of the linearly varying potential in the element. The presented method is implemented in the three-dimensional poisson's equation solver running under the windows 95. The accuracy and the convergence chaacteristics of the three-dimensional poisson's equation solver are compared with those of DAVINCI for the PN junction diode and the n-MOSFET under the thermal equilibrium and the DC reverse bias. The potential distributions of the simulatied devices from the three-dimensional poisson's equation solver, compared with those of DAVINCI, has a relative error within 2.8%. The average number of iterations needed to obtain the solution of the PN junction diode and the n-MOSFET using the presented method are 11.47 and 11.16 while the those of DAVINCI are 21.73 and 23.0 respectively.

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Analytical Study of Beam-to-HSS/CFT Column Connections by Trapezoidal External Stiffener

  • Rezaifar, Omid;Younesi, Adel
    • International journal of steel structures
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    • v.17 no.2
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    • pp.579-592
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    • 2017
  • Use of continuity plates in box columns is approved by design codes. To meet seismic parameters, considering performance problems and lack of confidence in the quality of the connections due to closed section, unsuitable vision and extreme welding and cutting at junction, continuity plates have been removed from the column and replaced by external stiffener. In this study, behavior of box beam-to-column connections with/without continuity plates, with external stiffener in two states with/without concrete (CFT/HSS) inside the column and finally reinforced connection by horizontal bar mats in CFT (Concrete Filled Tube) column have been studied by finite elements modeling and nonlinear analysis under monotonic and cyclic loadings. The results have shown that the use of external stiffener rather than continuity plate causes to increase 1% in rigidity and in turn 46.09% in strength. On the other hand, the use of filler concrete in column has caused to improve seismic behavior of the connection. When this connection containing the combination of external stiffeners and horizontal bar mats in CFT column is taken place, rigidity and strength parameters will be increased 3.01% and 108.8% respectively, compared to connections with no horizontal bar mats. In addition, the proposed connection has best performance in terms of both stress distribution and energy absorption and meets rigid connection criterion as well.

A Design of Signal Junction Box with an Integrated Connector-Filter (일체형 커넥터-필터를 적용한 신호인입함 설계)

  • Sung, Kyunghun;Park, Seungsang;Nam, Wongtae;Go, Junghwan
    • Proceedings of the Korea Information Processing Society Conference
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    • pp.76-77
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    • 2018
  • 전자기파 환경을 고려한 장비 개발을 위해서 고려되는 설계 사항 중 하나는 외부의 노이즈가 장비 내부로 유입되지 않도록 하고 반대로 장비 내 발생하는 노이즈가 외부로 나가는 것을 막도록 설계하는 것이다. 이를 위해서 전자기파 환경 규격을 만족하기 위한 장비들은 일반적으로 차폐형 구조로 설계된다. 본 논문은 차폐형 구조 설계 시 가장 노이즈에 취약할 수 있는 커넥터를 필터 일체형으로 설계한 사항과 이를 적용한 신호인입함의 성능 개선 사항에 대해 소개한다.

Characteristics of Thermal Radiation Pastes Containing Graphite and Carbon Nanotube (흑연 및 탄소나노튜브 혼합 방열도료의 특성)

  • Lee, Ji Hun;Song, Man-Ho;Kang, Chan Hyoung
    • Journal of the Korean institute of surface engineering
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    • v.49 no.2
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    • pp.218-224
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    • 2016
  • Thermal radiation pastes were prepared by dispersing carbon materials as fillers with a content of 1 weight percent in an acrylic resin. The kind of fillers was as follows; $25{\mu}m$ graphite, $45{\mu}m$ graphite, $15{\mu}m$ carbon nanotube(CNT), a 1:1 mixture of $25{\mu}m$ graphite and $15{\mu}m$ CNT, and a 1:1 mixture of $45{\mu}m$ graphite and $15{\mu}m$ CNT. Thermal emissivity was measured as 0.890 for the samples with graphite only, 0.893 for that with CNT only, and 0.892 for those containing both. After coating prepared pastes on a side of 0.4 mm thick aluminium plate and placing the plate over an opening of a box maintained at $92^{\circ}C$ with the coated side out, the temperatures on the uncoated side of the plates were measured. The samples containing graphite and CNT showed the lowest temperatures. The paste with mixed fillers was coated on the back side of the PCB of an LED module and thermal analysis was carried out using Thermal Transient Tester (T3ster) in a still air box. The thermal resistance of the module with coated PCB was measured as 14.34 K/W whereas that with uncoated PCB was 15.02 K/W. The structure function analysis of T3ster data revealed that the difference between junction and ambient temperatures was $13.8^{\circ}C$ for the coated case and $18.0^{\circ}C$ for the uncoated. From the infrared images of heated LED modules, the hottest-spot temperature of the module with coated PCB was lower than that of the uncoated one for a given period of LED operation.

MICROLEAKAGE OF 4 DIFFERENT COMPOSITE RESIN RESTORATIONS IN CLASS II CAVITY WITH CEMENTAL MARGIN (백악질 변연을 갖는 2급 와동에 충전된 4종 복합레진의 미세누출)

  • 조영곤;한세희;김은성
    • Restorative Dentistry and Endodontics
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    • v.26 no.6
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    • pp.492-498
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    • 2001
  • The purpose of this study was to evaluate four different composite resins in vitro for microleakage in Class II box type restorations that have gingival margins apical to the cementoenamel junction. Forty caries free extracted human molars were used in this study. The Class II cavities were prepared 1.0mm below cementoenamel junction with a #701 carbide bur. The teeth were randomly divided into four groups, each group comprising 20 treated cavities according to adhesives and filling materials ; Group 1: Scotchbond Multipurpose/Z 100. Group 2: Ariston Liner/Ariston pHc, Group 3: One Step/Pyramid, Group 4: Prime & Bond NT/SureFil. To simulate the clinical situation during restoration placement, a restoration template was fabricated and composite resin was filled using a three sited light-curing incremental technique. The specimens were stored in the 100% humidity for 7 days prior to thermocycling. The specimens were immersed in 2% methylene blue dye solution for 24 hours and then embeded in transparent acrylic resin and sectioned mesiodistally with a diamond wheel saw. The degree of marginal leakage was scored under the stereomicroscope($\times$20) and the data were analyzed by Kruskal Wallis test and Mann Whitney test. (omitted)

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Fabrication and Electrical Characteristics of $p^{+}$-n Ultra Shallow Junction Diode with Co/Ti Bilayer Silicide (Co/Ti 이중막 실리사이드를 이용한 $p^{+}$-n극저접합 다이오드의 제작과 전기적 특성)

  • Chang, Gee-Keun;Ohm, Woo-Yong;Chang, Ho-Jung
    • Korean Journal of Materials Research
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    • v.8 no.4
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    • pp.288-292
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    • 1998
  • The p*-n ultra shallow junction diode with Co/Ti bilayer silicide was formed by ion implantation of $BF_{2}$ energy : 30KeV, dose : $5\times10^{15}cm^{-2}$] onto the n-well Si(100) region and RTA-silicidation of the evaporated Co($120\AA$)/Ti($40\AA$) double layer. The fabricated diode exhibited ideality factor of 1.06, specific contact resistance of $1.2\times10^{-6}\Omega\cdot\textrm{cm}^2$ and leakage current of $8.6\muA/\textrm{cm}^2$(-3V) under the reverse bias of 3V. The sheet resistance of silicided emitter region, the boron concentration at silicide/Si interface and the junction depth including silicide layer of ($500\AA$ were about $8\Omega\Box$, $6\times10^{19}cm^{-3}$, and $0.14\mu{m}$, respectively. In the fabrication of diode, the application of Co/Ti bilayer silicide brought improvement of ideality factor on the current-voltage characteristics as well as reduction of emitter sheet resistance and specific contact resistance, while it led to a little increase of leakage current.

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Gate Location Design of an Automobile Junction Box with Integral Hinges (복합힌지를 갖는 차량용 정션박스의 게이트 위치설계)

  • 김홍석
    • Transactions of Materials Processing
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    • v.12 no.2
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    • pp.134-140
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    • 2003
  • Polymers such as polypropylene or polyethylene offer a unique feature of producing an integral hinge, which can flex over a million times without causing a failure. With such advantage manufacturing, time and cost required at the assembly stage can be eliminated by injecting the whole part as one piece. However, due to increased fluidity resistance at hinges during molding, several defects such as short shot or premature hinge failure can occur with the improper selection of gate locations. Therefore, it is necessary to optimize flow balancer in injection molding of part with hinges before actually producing molds. In this paper, resin flow patterns depending on several gate positions were investigated by numerical analyses of a simple strip part with a hinge. As a result, we found that the properly determined gate location leads to better resin flow and shorter hesitation time. Finally, injection molding tryouts using a mold that was designed one of the proposed gate systems were conducted using polypropylene that contained 20% talc. The experiment showed that hinges without defects could be produced by using the designed gate location.

An in-vitro investigation of microleakage of sandwich restorations with flow able liner in class II cavaties with cervical margins in dentine

  • Lee, Kang;Hong, Chan-Ui
    • Proceedings of the KACD Conference
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    • pp.586.1-586
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    • 2001
  • Large butt-joint box typed class II cavites with cervical margins 1mm below the cemento-enamel junction were cut into 70 extracted human molars. The cavities(7 groups, n=10) were filled using a closed/open sandwich restoration or total bond restoration technique with materials according to the manufacturer's recommandation using the single-component bonding agent for each system. Teeth were thermocycled 500 times between $5^{\circ}C$ and $55^{\circ}C$ with 30-second dwell times.(omitted)

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Implementation of an Automated Visual Inspection System for the Junction Box (정션박스 자동 시각 검사 시스템 구현)

  • Heo Seheung;Hahn Kwangsoo;Choi JoonSoo;Lee Hojun
    • Proceedings of the Korean Information Science Society Conference
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    • pp.862-864
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    • 2005
  • 자동차 전자 부품 중 하나인 정션박스의 자동 시각 검사 시스템은 사랑의 육안 검사를 자동화함으로써, 정확하고 빠른 검사가 가능하다. 또한 검사 결과를 데이터베이스화하여 지속적인 불량 발생요인을 분석할 수 있기 때문에 불량률을 감소시켜 제품 신뢰도를 향상시킬 수 인다. 본 연구에서는 정션박스에 삽입된 퓨즈와 릴레이의 유무 및 오결합을 자동으로 검사하는 자동 시각 검사 시스템을 구현하였고 이를 적용한 결과 신속하고 정확한 검사가 가능함을 보였다.

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