• Title/Summary/Keyword: hole-board

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Finite Element Analysis of a Ventilating Box Structure (통기성 상자 구조물에 대한 유한요소 해석)

  • 박종민;권순구
    • Journal of Biosystems Engineering
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    • v.27 no.6
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    • pp.557-564
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    • 2002
  • Corrugated board is an efficient low-cost structure material fur the boxes that are widely used for transporting, storing and distributing goods. Corrugated board is also considered as an orthotropic because the principal material directions are the same as in paperboard. The purpose of this study was to elucidate the principal design parameters of ventilating box through the FEA on the various types of ventilating hole. From the viewpoint of the stress distribution and stress level, the optimum pattern and location of the ventilating hole were vertically oblong, and symmetry position with a short distance to the right and left from the center of front and rear panel. And, the optimum location and pattern of hand hole were a short distance to the top from the center of both side panels, and modified shape to increase the radius of curvature of both side in horizontal oblong. In general, the optimum pattern and location of both the ventilating hole and hand hole based on the FEM analysis were well verified by experimental investigation. It is suggested that decrease in compressive strength of the box could be minimized in the same ventilating hole area under the condition of the length of major axis of ventilating hole is less than 1/4 of box length, the ratio of minor axis/major axis is 113.5∼l/2.5, and number of the ventilating holes is even and symmetrical.

Empirical Model of Via-Hole Structures in High-Count Multi-Layered Printed Circuit Board (HCML 배선기판에서 비아홀 구조에 대한 경험적 모델)

  • Kim, Young-Woo;Lim, Yeong-Seog
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.12
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    • pp.55-67
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    • 2010
  • The electrical properties of a back drilled via-hole (BDH) without the open-stub and the plated through via-hole (PTH) with the open-stub, which is called the conventional structure, in a high-count multi~layered (HCML) printed circuit board (PCB) were investigated for a high-speed digital system, and a selected inner layer to transmit a high-speed signal was farthest away from the side to mount the component. Within 10 GHz of the broadband frequency, a design of experiment (DOE) methodology was carried out with three cause factors of each via-hole structure, which were the distance between the via-holes, the dimensions of drilling pad and the anti-pad in the ground plane, and then the relation between cause and result factors which were the maximum return loss, the half-power frequency, and the minimum insertion loss was analyzed. Subsequently, the empirical formulae resulting in a macro model were extracted and compared with the experiment results. Even, out of the cause range, the calculated results obtained from the macro model can be also matched with the measured results within 5 % of the error.

Strength Optimization of Ventilating Container(II)-Finite Element Analysis (통기성 상자 구조물의 강도적 최적화 연구(II)-유한요소해석)

  • Park, Jong-Min
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.7 no.2
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    • pp.25-30
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    • 2001
  • Corrugated board is composed of cellulose fibers which are arranged with the same direction as the board manufactured. The direction is classified with machine direction (MD) and cross-machine direction (CD). Therefore, corrugated board is orthotropic material that has totally different strength properties at each direction and especially, at machine direction, the mechanical properties of fiberboard is superior. The compression strength of the corrugated fiberboard boxes is very important information to the manufacturers and the end users. This study was carried out to design the optimum pattern, size, and location of ventilating hole for ventilating container through the finite element analysis. The optimum pattern and location of ventilating and hand hole were vertical oblong, a short distance to the right and left from the center of panel, and center or a short distance to the top of both sides, respectively. We identified the effect on both stress dispersion and stress level from the analysis of redisigned hand hole.

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THE RECENT TREND OF BUILD-UP PRINTED CIRCUIT BOARD TECHNOLOGIES

  • Takagi, Kiyoshi
    • Journal of the Korean institute of surface engineering
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    • v.32 no.3
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    • pp.289-296
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    • 1999
  • The integration of the LSI has been greatly improved and the circuit patters on the LSI are becoming finer line and pitch. The high-density electronic packaging technology is improved. In order to realize the high-density packaging technology, the density of the circuit wiring of the printed circuit boards have also been more dense. The build-up process multilayer printed circuit board technology have a lot of vias, possibilities of the finer conductor wirings and have a freedom of capabilities of wiring design. The build-up process printed circuit boards have the wiring rules which are the pattern width: $100-20\mu\textrm{m}$, the via hole diameter: $100-50\mu\textrm{m}$. There three kinds of build-up processes as far materials and hole drilling. In this paper, the recent technology trends of the build-up printed circuit board technologies are described.

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The Effect of Internal Nail-holes on the Bending Strength of Particle Board (못접합에 의한 내부천공이 삭편판(PB)의 휨강도에 미치는 영향)

  • So, Won-Tek
    • Journal of the Korea Furniture Society
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    • v.19 no.3
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    • pp.211-218
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    • 2008
  • This experiment was carried out to investigate the effect of internal holes on the bending strength of PB. The diameters of holes are 0mm to 13mm. The locations of holes are 1/8 to 4/5 point horizontally from sample end and are 1/5 to 4/5 vertically from sample surface, the numbers of holes are 1 to 4 pcs. In the size of internal holes, the bending strengths of PB were decreased significantly with the increase of diameter of holes, and the relationship between diameters(D) of holes and bending strength (${\sigma}_b$) of PB was ${\sigma}_b=-11D+168.8$ ($r^2=-0.99^{**}$). The effects of hole-locations and hole-numbers on the bending strengths of PB were large. and so they should be considered as major factors for the jointing design of PB.

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Anxiolytic Effects of Quercetin: Involvement of GABAergic System (Quercetin의 항불안 효과: GABA 신경계를 중심으로)

  • Jung, Ji Wook;Lee, Seungheon
    • Journal of Life Science
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    • v.24 no.3
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    • pp.290-296
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    • 2014
  • The present experiment investigated putative anxiolytic-like effects of quercetin using an elevated plus-maze (EPM) and hole-board apparatus test in mice. Quercetin is a flavonoid widely distributed in nature. Quercetin (1.25, 2.5, 5, or 10 mg/kg) was orally administered to ICR mice 1 h before a behavioral evaluation in the EPM. Control mice were treated with an equal volume of vehicle, and positive control mice were treated with buspirone (2 mg/kg, i.p.). The mice administered quercetin (5 mg/kg) spent a significantly longer percentage of time in the open arms of the EPM and their percentage of entries into the open arms was significantly increased compared to the vehicle-treated controls (p<0.05). The anxiolytic-like activities of quercetin were antagonized by trans-4-aminocrotonic acid (a $GABA_{A-{\rho}}$ agonist, 20 mg/kg) but not by flumazenil (a $GABA_A$ antagonist, 10 mg/kg) or WAY-100635 (a $5-HT_{1A}$ antagonist, 0.3 mg/kg). Moreover, there were no changes in the locomotor activity or myorelaxant effects in any group compared with the vehicle-treated controls. In the hole-board apparatus test, the number of head-dips increased significantly in the single treatment with quercetin (5 mg/kg) group compared to the vehicle-treated controls (p<0.05). These findings suggest that quercetin can promote anxiolytic-like activity, mediated by the GABAergic nervous system, in mice.

Development of the Latest High-performance Acid Copper Plating Additives for Via-Filling & PTH

  • Nishiki, Shingo
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.4
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    • pp.39-43
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    • 2012
  • Via-filling plating and through-hole plating are absolutely imperative for manufacturing of printed-wiring board. This Paper is introducing the latest developments of our company worked on the high-performance of acid copper plating additives for them.

A Study on the Physical Properties of MgO Board for Wall System (경량 벽체용 MgO 보드의 물리적 특성에 관한 실험적 연구)

  • Kim, Soon-Ho;Kim, Hong-Yong
    • KIEAE Journal
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    • v.7 no.4
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    • pp.135-140
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    • 2007
  • In this study we settled the trouble of the MgO board of existence by this research. We changed the wooden one of the main ingredient of a board to a perlite and a mineral particle in the aluminum hydroxide group and proceeded with a study to physical character and fire resistance efficiency improvement. The result yellowing phenomenon could be improved and it was possible to reduce size decrease of pin hole and the frequency of occurrence. We found out that the in case of absorbed amount added 5~8% corresponding to the weight decreases the acrylic group emulsion suddenly. So this product is improved with the bending strength and water-resistance. After behavior stop time measurement of a mouse for experiments was measured at the time of a gas harmful effect test, an improved MgO board appeared more highly for an average of 138 seconds compared with a board of existence.

Development of Force/Torque Sensor and Compliance Algorithm for Assembly Robots (조립용 로보트의 힘.토오크 센서 및 컴플라이언스 알고리즘의 개발)

  • Ko, Nak-Yong;Ko, Myoung-Sam;Ha, In-Joong;Lee, Bum-Hee
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.244-248
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    • 1987
  • The force/torque sensor for robot is developed. The compliance algorithm for peg-in-hole insertion task using the forec/troque sensor is developed. The system consists of an IBM PC, robot, force/torque sensor, strain meter, A/D board, and interface board. The IBM PC functions as a main processor and the robot controller as a slave processor. The sensor is constructed to measure $T_x$, $T_y$, $F_z$ which are necessary to precisely execute a peg-in-hole insertion task by SCARA type assembly robot. The outputs of sensor are analyzed. On the basis of the analysis, compliance algorithm for peg-in-hole insertion task is developed. Some comments concerning the development of wrist force/torque sensor and compliance algorithm are given.

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