• Title/Summary/Keyword: Form work

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The Characteristics of Occupational Injury in Small Manufacturing Factory (소규모 사업장의 산업재해 특성과 예방대책에 대한 연구)

  • 김유창
    • Journal of the Korean Society of Safety
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    • v.13 no.2
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    • pp.145-150
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    • 1998
  • The production activity by human is accompanied by various accidents which resulted in human and property loss. If information on these industrial accidents could be collected and analyzed for the purpose of preventing industrial accidents, we would be able to get rid of industrial accidents. The accidents which involved absence from work at least 4 days in small manufacturing factories were considered in this study. 84 accidents which occurred in 1995 were investigated. These accidents were analyzed in terms of employment sector, work period, cause of accident and form of accident. The accidents of small manufacturing factories are numerous and are often serious and worthy of greater attention than they have received. Successful strategies for accident prevention depend on effective analysis.

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TRANSFORMATION OF DIMENSIONLESS HEAT DIFFUSION EQUATION FOR THE SOLUTION OF DYNAMIC DOMAIN IN PHASE CHANGE PROBLEMS

  • Ashraf, Muhammad;Avila, R.;Raza, S. S.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.13 no.1
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    • pp.31-40
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    • 2009
  • In the present work transformation of dimensionless heat diffusion equation for the solution of moving boundary problems have been formulated. The formulation is based on 1-D, 2-D and 3-D, unsteady heat diffusion equations. These equations are rst turned int dimensionless form by using dimensionless quantities and their transformation was formulated in liquid and solid phases. The salient feature of this work is that during the transformation of dimensionless heat diffusion equation there arises a convective term $\tilde{v}$ which is responsible for the motion of interface in liquid as well as solid phase. In the transformed heat equation, a correction factor $\beta$ also arises naturally which gives the correct transformed flux at interface.

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Evaluation of Field Application on the Prediction Method of Early-age Strength of Early Concrete for Construction Work Period Reduction (공기단축 조강콘크리트의 조기강도 예측기술의 현장적용성 평가)

  • Lee, Woong-Jong;Keum, Kyoung-Hun;Lee, Jae-Hyun;Jung, Yang-Hee;Kim, Yong-Ro
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.443-444
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    • 2010
  • In this study, It is confirmed the validity for determination of the form removal time, utilizing prediction expression for early-stage strength which depended on the variation of curing history for early strength concrete which be passible to construction work period reduction, in apartment.

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A Study on the Development of Automation Unloader for Press Metalmold (프레스 금형용 Unloader 자동화 시스템개발에 관한 연구)

  • 김재열
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.10a
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    • pp.156-160
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    • 1996
  • In this study of made Unloader is moving linear transfer system for mainly plastic working or forming of small electronic unit and other at press line. This machine for lading and unloading a workpiece has been installed in a press in order to load and unload a workpiece form a press die. Control method be used PLC. it took data of input from each sensor and send signal of output to actuator today we have a lot of problem at work of press line. most of press work be operated by human so they often hurted terreble accident by press machine. Because press working system in automotive factories are now changing over to a transfer press working system this Unloader will give more easily and speedy production and manpower saving less of pruduction cost high perfomance

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Conductance of a Single Molecule Junction Formed with Ni, Au, and Ag Electrodes

  • Kim, Taekyeong
    • Journal of the Korean Chemical Society
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    • v.58 no.6
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    • pp.513-516
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    • 2014
  • We measure the conductance of a 4,4'-diaminobiphenyl formed with Ni electrodes using a scanning tunneling microscope-based break-junction technique. For comparison, we use Au or Ag electrodes to form a metal-molecular junction. For molecules that conduct through the highest occupied molecular orbital, junctions formed with Ni show similar conductance as Au and are more conductive than those formed with Ag, consistent with the higher work function for Ni or Au. Furthermore, we observe that the measured molecular junction length that is formed with the Ni or Au electrodes was shorter than that formed with the Ag electrodes. These observations are attributed to a larger gap distance of the Ni or Au electrodes compared to that of the Ag electrodes after the metal contact ruptures. Since our work allows us to measure the conductance of a molecule formed with various electrodes, it should be relevant to molecular electronics with versatile materials.

Bond-Slip Model for FRP-Concrete Interface II: Characteristics of Adhesive Joint (FRP-콘크리트 계면의 부착모델 II : 부착특성)

  • 조정래;조근희;박영환;박종섭;유영준;정우태
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.902-907
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    • 2003
  • Substantial experimental and theoretical work exists on the bond characteristics of FRP-concrete adhesive joints. Analytic solutions based on fracture mechanics are most commonly accepted for theoretical work on joint. The solutions may be derived for the simple form of the shear strees-slip curve. And it is difficult to determine the model parameters consisting the curve. In this study, the bilinear curve with softening branch is introduced. The model parameters are determined by the method described by the companion paper with comparison of test results. There are many uncertainties in the test results of CFRP sheet adhesive joints, so that test results used for the construction of the regression problem should be reasonably selected.

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Behaviour of the Twill Weave Woven Fabrics during Relaxation

  • Alamdar-Yazdi A.
    • Fibers and Polymers
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    • v.6 no.4
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    • pp.306-312
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    • 2005
  • This work looks into the behaviour of the twill weave woven fabrics during relaxation (when the weaving tension is released). Ten, 50-metre rolls of twill weave woven fabrics were produced. The fabrics were marked in a rectangular form at the weaving loom. After 48 hours of relaxation, the new shapes and sizes were recorded. The shapes of almost all of the samples were changed to parallelogram, even though they differed in size. The work showed that the manner of fabric deformation during relaxation depends upon the fabric structure. It indicates that contraction due to relaxation of the twill weave causes the woven fabric to skew. in the direction of the twill. The quantity of the skewness is related to the float length and the twill type. Fabrics with longer float length have higher skewness.

Globally Optimal Solutions for Cross-Layer Design in Fast-Fading Lossy Delay-Constrained MANETs

  • Pham, Quoc-Viet;Kim, Hoon;Hwang, Won-Joo
    • Journal of Korea Multimedia Society
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    • v.18 no.2
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    • pp.168-177
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    • 2015
  • To increase the overall utility and decrease the link delay and power consumption, a joint optimal cross-layer design of congestion control at the transport layer, link delay at the data link layer and power allocation at the physical layer for mobile ad hoc networks is considered in this paper. As opposed to previous work, the rate outage probability in this work is based on exactly closed-form; therefore, the proposed method can guarantee the globally optimal solutions to the underlying problem. The non-convex formulated problem is transformed into a convex one, which is solved by exploiting the duality technique. Finally, simulation results verify that our proposal achieves considerable benefits over the existing method.

Optimal Retirement Time and Consumption/Investment in Anticipation of a Better Investment Opportunity

  • Shim, Gyoocheol
    • Management Science and Financial Engineering
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    • v.20 no.2
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    • pp.13-25
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    • 2014
  • We investigate an optimal retirement time and consumption/investment policy of a wage earner who expects to find a better investment opportunity after retirement by being freed from other work and participating fully in the financial market. We obtain a closed form solution to the optimization problem by using a dynamic programming method under general time-separable von Neumann-Morgenstern utility. It is optimal for the wage earner to retire from work if and only if his wealth exceeds a certain critical level which is obtained from a free boundary value problem. The wage earner consumes less and takes more risk than he would without anticipation of a better investment opportunity.

Cultivation of Peach by Orgnic Farming (유기농업에 의한 복숭아 재배)

  • 이석영;유창성
    • Korean Journal of Organic Agriculture
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    • v.6 no.1
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    • pp.45-50
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    • 1997
  • Cultivation of peach by organic farming and cooperative form of work was attempted. The compost was made from egg shells and bread residues(bakery residues), falling leaves, and weeds. The cooperative teams of work were farmers, students and members of citizens' movement. The responses of participants for composting, though it's laboriousness and dirtiness, were favorable with feeling of doing good for social services. 20 chickens were raised in the peach orchard as one of the mixed farming. The pH and Ca content of ripened compost were 7.7 and 1.57 %, respectively. Controlling Aphids(plant louse)by ladybug was observed vividly. The size and sugar concentration were comparable to standard values even though rainy season and the number of damaged fruits were less than half(40%).

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