• Title/Summary/Keyword: Alternative Means

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A Study of Longitudinal Forces and Displacements in a Multi-Span Bridge Equipped with a CWR Track (장대레일이 설치된 교량에서의 축방향 변위 및 축력 변화 연구)

  • Lee, Joo-Heon;Huh, Young
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.442-449
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    • 1999
  • Due to temperature variations, considerable longitudinal rail forces and displacements may develop in continuous welded rail(CWR) track on long-span bridges or viaducts. Excessive relative displacements between sleepers and ballast bed may disturb the stable position of the track in the ballast which results in a lower frictional resistance. Generally, these problems are solved by installing rail expansion devices. However the application of expansion devices in high-speed tracks on existing bridges, as a means to prevent excessive longitudinal displacements and forces, is not attractive method due to comfort, safety and maintenance aspects. An alternative and very effective solution is possibly the use of so-called zero longitudinal restraint(ZLR) fastenings over some length of the track. The calculations, carried out in this respect, show a considerable reduction of track displacements, track forces, and the relative sleeper/ballast displacements. This reduction depends on the length over which these fastenings are installed. In this paper calculations of the longitudinal displacments and forces in a CWR track and substructure resulting from thermal, mechanical and kinematical loads were carried out using the FEM analysis program LUSAS

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A Feasibility Investigation of adoption for the Seat-type Express Electric railway on the Railroad in Metropolitan area - Focus on the double tracked Seoul-Chuncheon line - (광역철도 좌석형급행열차 도입 타당성에 관한 연구 - 경춘선 복선화구간 중심으로 -)

  • Park, Min-Kyu;Kim, Si-Gon
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.1447-1457
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    • 2008
  • The operation of the Seat-type Express Electric railway (SEE) has been watched for an alternative plan according to the increase of competition among the vehicle in metropolitan city. The purpose of this study was to examine a feasibility for the adoption of the SEE by analysis of various condition in the double tracked Souel-Chuncheon line. Fare estimate, station selection for SEE, managerial plan, demanding forecasting and analysis were performed to compute financial efficiency. The results showed financial validity on Revenue Cost Ratio (R/C), Financial Net Present Value (FNPV), Financial Internal Rate of Return (FIRR). This results indicate the evidence that SEE is a new means which is able to complement for finance, transportation capacity in metropolitan city.

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A Study on The Estimation of Accident Loss Prevention Cost and Risk Analysis in Subway Construction (지하철 건설현장 재해 분석 및 재해손실비용 추정에 관한 연구)

  • 최명기
    • Journal of the Korean Professional Engineers Association
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    • v.34 no.5
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    • pp.77-81
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    • 2001
  • The industrial accident in subway of late is increasingly coming to the front as a serious problem of society because a scale of industrial accident is a large size, and powerfulness, while the percent of accident is decreasing as a result of industrial facilities with the largeness of equipment, automation, and high horse-powering. In this paper, a study on the estimation of accident loss prevention cost and risk analysis in subway construction is proposed as an alternative to the techniques currently used in the general construction projects safety. Then the concept of risk evaluation using a risk assessment model is presented to drive value of risk and numerical example for risk analysis. A means for this does grasp the importance of educational factor by way of analyzing the causes of accident through statistical data of labor department, emphasizing the necessity and the importance of safety education, being helpful to act safety by decreasing insecure activity which ranks the majority of accident causes with putting the education program, form, method into practice that are suitable for a place of business.

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The Analysis Method of Integrated Logistic System using Evolution Strategies and Data Envelopment Analysis (진화전략과 DEA를 이용한 통합 물류 시스템 분석 방법)

  • Um In-Sup;Lee Hong-Chul;Kang Jeong-Yun
    • Journal of the Korea Society for Simulation
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    • v.13 no.4
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    • pp.17-29
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    • 2004
  • The focus of this study is to represent a methodology of analysis for integrated logistic system by means of the Evolution Strategies and Data Envelopment Analysis(DEA). The integrated logistic system is composed of AS/RS (Automated Storages and Retrieval System), AGVs(Automated Guided Vehicle System) and Conveyor System. We design the simulation alternatives with choosing the qualitative critical factors for the each subsystem. Evolution Strategies is used to optimize the quantitative critical factors and responses of each alternative. DEA is applied to measure the efficiency of the alternatives in order to select the optimal operation efficiency scheme. The method of analysis which combines Evolution Strategies with DEA can be used to analyze the qualitative and quantitative critical factors in the integrated logistic systems.

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Response effects of the mode of data collection (자료수집 양식의 응답효과)

  • 박용치
    • Survey Research
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    • v.1 no.1
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    • pp.21-43
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    • 2000
  • Although telephone surveys are an attractive alternative to household interviews it is important to determine whether the data collected by the two methods are comparable. To answer this question, findings from the telephone survey literatures are examined in the view point of i) direct effect which means expressions of preference of the interview detail of answers on open questions and item missing data rates ii) statistical estimates and iii) differences of interviewers and data collection modes. Differences are explained by social desirability effects on the telephone, cognitive ability of the survey question, and mode effects and interviewer effects.

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The Teacher's Perspectives on Students' Language Anxiety

  • Shin, Soo-Jeong
    • English Language & Literature Teaching
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    • v.9 no.1
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    • pp.67-82
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    • 2003
  • This paper is aimed at the investigation of the teacher's perspectives on students' language anxiety. The teachers who participated in this study include six Asian ESL teachers from four different countries: Korea, Japan, Taiwan, and China. The methodology employed by this case study, helped to determine teachers' perspectives on students' language anxiety. This study, which was conducted by means of in-depth interviews with six experienced language teachers, offered some alternative insights on language anxiety from a different perspective. The findings indicate that the participants' views on language anxiety management seem to be fairly consistent with their own beliefs about teaching and their own assumptions about the role of the teacher.

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SOME FAMILIES OF INFINITE SERIES SUMMABLE VIA FRACTIONAL CALCULUS OPERATORS

  • Tu, Shih-Tong;Wang, Pin-Yu;Srivastava, H.M.
    • East Asian mathematical journal
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    • v.18 no.1
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    • pp.111-125
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    • 2002
  • Many different families of infinite series were recently observed to be summable in closed forms by means of certain operators of fractional calculus(that is, calculus of integrals and derivatives of any arbitrary real or complex order). In this sequel to some of these recent investigations, the authors present yet another instance of applications of certain fractional calculus operators. Alternative derivations without using these fractional calculus operators are shown to lead naturally a family of analogous infinite sums involving hypergeometric functions.

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Fuzzy ANP Application for Vender Prioritization (공급업체 우선순위 선정을 위한 Fuzzy ANP의 활용)

  • Jung, Uk
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.34 no.2
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    • pp.9-18
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    • 2011
  • Vender prioritization process is one of the most critical tasks of production and logistics management for many companies. Determining the most critical criteria for vender prioritization process is a vital means for a purchasing company to improve its supply chain productivity. This study discuss the use of a Fuzzy analytic network process (Fuzzy ANP) model which is an efficient tool to handle the fuzziness of the data involved in deciding the preferences of different criteria which are not independent. Also, the comparison of classical ANP and Fuzzy ANP is described using simulation with triangular distribution random number generation. It is shown that Fuzzy ANP model possesses some attractive properties and could be used as an alternative to the known vender prioritization methods.

Performance studies on concrete with recycled coarse aggregates

  • Yaragal, Subhash C.;Teja, Dumpati C.;Shaffi, Mohammed
    • Advances in concrete construction
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    • v.4 no.4
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    • pp.263-281
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    • 2016
  • Concrete continues to be the most consumed construction material in the world, only next to water. Due to rapid increase in construction activities, Construction and Demolition (C&D) waste constitutes a major portion of total solid waste production in the world. It is important to assess the amount of C&D waste being generated and analyse the practices needed to handle this waste from the point of waste utilization, management and disposal addressing the sustainability aspects. The depleting natural resources in the current scenario warrants research to examine viable alternative means, modes and methods for sustainable construction. This study reports processing Recycled Coarse Aggregates (RCA) using a rod mill, for the first time. Parameters such as amount of C&D waste for processing, nature of charge and duration of processing time have been optimized for obtaining good quality RCA. Performance of RCA based concrete and performance enhancement techniques of 50% RCA based concrete are discussed in this paper.

A Study on the Influence of Redistributed Residual Stresses on Fatigue Crack Growth Behaviors in the Welded Plate with Various Thickness (변후용접판재의 피로균열성장거동에 미치는 재분포잔류응력의 영향에 관한 연구)

  • 차용훈
    • Journal of the Korean Society of Safety
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    • v.10 no.2
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    • pp.17-23
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    • 1995
  • Though the magnitude is decreasing, the compressive residual stress is always distributed during fatigue crack growth near the crack tip. This means that the residual stress is released during fatigue crack growth due to the alternative load. ${\Delta}K_{IV}$ is modified by using the initial residual stress and the redistributed residual stress in uniform and various thickness welded specimens. The former is denoted by ${\Delta}K_{IV.eff.i}$ and the latter is denoted by ${\Delta}K_{IV.eff.i}$. ${\Delta}K_{IV.eff.i}$ gives more accurate relations in da/dN vs. ${\Delta}K_{IV}$ curve, however the difference is very small.

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