• Title/Summary/Keyword: Life Cycle Analysis

Search Result 2,042, Processing Time 0.031 seconds

Life cycle reliability analyses of deteriorated RC Bridge under corrosion effects

  • Mehmet Fatih Yilmaz
    • Earthquakes and Structures
    • /
    • v.25 no.1
    • /
    • pp.69-78
    • /
    • 2023
  • Life-cycle performance analysis of a reinforced concrete box section bridge was generated. Moreover, Monte Carlo simulation with important sampling (IS) was used to simulate the bridge material and load uncertainties. The bridge deterioration model was generated with the basic probabilistic principles and updated according to the measurement data. A genetic algorithm (GA) with the response surface model (RSM) was used to determine the deterioration rate. The importance of health monitoring systems to sustain the bridge to give services economically and reliably and the advantages of fiber-optic sensors for SHM applications were discussed in detail. This study showed that the most effective loss of strength in reinforced concrete box section bridges is corrosion of the reinforcements. Due to reinforcement corrosion, the use of the bridge, which was examined, could not meet the desired strength performance in 25 years, and the need for reinforcement. In addition, it has been determined that long-term health monitoring systems are an essential approach for bridges to provide safe and economical service. Moreover the use of fiber optic sensors has many advantages because of the ability of the sensors to be resistant to environmental conditions and to make sensitive measurements.

Life Cycle Assessment(LCA) of Rolling Stock (철도차량시스템의 전과정평가(LCA))

  • Kim Yong-Ki;Yoon Hee-Taek;Jung Woo-Sung
    • Proceedings of the KSR Conference
    • /
    • 2004.10a
    • /
    • pp.533-538
    • /
    • 2004
  • Rolling Stock life cycle can not provide weakness of environment due to the absence DB on about environment information for contaminant, expense analysis on each step which consists of raw material-design-manufacture-running-waste step. In order to estimate environmental impacts on LCA for rolling stock system, scientifically and internationally fair standards of assessment method for pursuing environmental friendly in environment regulation policy, application of LCA system is proposed and introduced in the present paper.

  • PDF

A Presentation of a Cost Classification System for Gas Plant Construction Projects

  • Park, Moonsun;Kim, Yongsu
    • International conference on construction engineering and project management
    • /
    • 2015.10a
    • /
    • pp.625-626
    • /
    • 2015
  • The purpose of this study is to present a cost classification system that can be used in gas plant construction projects. Towards this end, it examined the detailed statements of the construction companies which had experience in carrying out plant construction projects. Based on the above, it also presented a life-cycle (i.e., EPCC) cost classification system for the gas plant construction projects by conducting the Delphi analysis through the expert opinions.

  • PDF

A Study for the Improvement of the Life Cycle of Press Die using Wire Cut Discharge Machining (와이어 컷 방전가공 시 프레스금형 수명 향상에 대한 고찰)

  • Yun, Jae-Woong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.18 no.9
    • /
    • pp.61-67
    • /
    • 2017
  • Research into the selection of suitable materials and the development of fast processing methods for press die manufacturing is absolutely necessary to reduce the production time and cost. In particular, knowledge of its heat properties must be considered whendeveloping a long press die. Generally, as the main component materials of press dies, Cr, W low alloy tool steel, high carbon-high chrome steel, high speed steel, etc., are used as thetooling steel for the cold die. Machine tools and wire-cut electric discharge machining are mainly used for processing the press die parts. There are many differences in the machining time and life cycle of die parts depending on the machining process. The parts produced by milling and grinding have a high manufacturing time and cost with a long life cycle, while thosemade by milling and wire-cut discharge machining have areduced manufacturing time and cost,whereastheir die life cycle is reduced. Therefore, in this study, we will discuss amethod of improving the life cycle of the die parts by using heat treatment as a processing method that reduces the manufacturing time and cost. SEM, EDS analysis and the surface roughness analysis of the surface and center of the workpiece are used for analyzing the specimens produced by three machining methods, viz. milling - grinding, milling - wire cut discharge, and milling - wire cut discharge - heat treatment. A method of making die parts having the same life cycle as those produced by milling - grinding is developed with the milling - wire cut discharge - high temperature tempering method.

Development Life Cycle-Based Association Analysis of Requirements for Risk Management of Medical Device Software (의료기기 소프트웨어 위험관리를 위한 개발생명주기 기반 위험관리 요구사항 연관성 분석)

  • Kim, DongYeop;Park, Ye-Seul;Lee, Jung-Won
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.6 no.12
    • /
    • pp.543-548
    • /
    • 2017
  • In recent years, the importance of the safety of medical device software has been emphasized because of the function and role of the software among components of the medical device, and because the operation of the medical device software is directly related to the life and safety of the user. To this end, various standards have been set up that provide activities that can effectively ensure the safety of medical devices and provide their respective requirements. The activities that standards provide to ensure the safety of medical device software are largely divided into the development life cycle of medical device software and the risk management process. These two activities should be concurrent with the development process, but there is a limitation that the risk management requirements to be performed at each stage of the medical device software development life cycle are not classified. As a result, developers must analyze the association of standards directly to develop risk management activities during the development of medical devices. Therefore, in this paper, we analyze the relationship between medical device software development life cycle and risk management process, and extract risk management requirement items. It enables efficient and systematic risk management during the development of medical device software by mapping the extracted risk management requirement items to the development life cycle based on the analyzed associations.

Comparative Analysis of Track Ballast Structures based on Value Engineering (가치공학에 기초한 궤도도상구조의 비교분석)

  • Baek, Jae-Wook;Song, Yoo-Seob;Park, Tae-Hyo
    • Proceedings of the KSR Conference
    • /
    • 2007.05a
    • /
    • pp.295-302
    • /
    • 2007
  • The objective of this paper is to evaluate the proposed design by the Value Engineering (VE) analysis for the gravel ballast and the concrete ballast track structures. However, reliabilities about the VE analysis results based on Life-Cycle Cost(LCC) has not been fully benefited from VE implementation due to disregard of basic principles and lack of systematic performance measurement systems. In this paper, the VE analysis using the Delphi survey of professional group is proposed to decide reasonable determinants for investment and alternative design in construction project of railway tracks. Moreover, the efficiency of VE analysis is invested by an application of the developed methodology to track structures.

  • PDF

A Study on the Basic Procedure of LCC Analysis for the Urban Transit Vehicle (도시철도 차량에서 LCC 분석의 기본 절차에 관한 연구)

  • Chung, Kwang-Woo;Jeon, Young-Seok;An, Joon-Yong;Kim, Chul-Su;Chung, Jong-Duk
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.643-652
    • /
    • 2009
  • This paper presents brief history and a state-of-the-art survey of Life Cycle Cost (LCC) analysis, in particular LCC analysis in the Urban Transit Vehicle, based on a internationl codes and standards related to LCC analysis. A main objective of the LCC analysis is to quantify the total cost of ownership of a product throughout its full life cycle, which includes research and development, construction, operation and maintenance, and disposal. The predicted LCC is useful information for decision making in purchasing a product, in optimizing design, in scheduling maintenance, or in planning overhaul. This paper presents a LCC procedure consisting of seven steps, which are "Problems definition", "Cost elements definition", "System modeling", "Data collection", "Cost profile development", "Evaluation", and "Verification". Sub-activities to be encompassed in the seven steps procedure are described.

  • PDF

Information Security Activity of Analysis Phase in Information Security Model in Accordance with SDLC

  • Shin, Seong-Yoon;Lee, Tae-Wuk
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.11
    • /
    • pp.79-83
    • /
    • 2016
  • In this paper, we define four levels of analysis, design, implementation, and testing of the configuration of the development phase by S/W development life cycle. In particular, it dealt with the stage of the analysis phase to prepare an information system developed intensively. Details of the derivation of the information security requirements, it can be seen that comes from the perspective of confidentiality, integrity, availability and accountability, etc. It dealt with from the first manifestations of the projects planning to final planning to establish information security in activities of the Information Security requirements. As an example exhibited by assessing the information security analysis phase activities of S corporations, it can be seen that the improved sales rise in information security activities.

A Study on Sensitivity Analysis of Life-Cycle Cost of Concrete Bridges (콘크리트 교량의 생애주기비용 민감도 분석)

  • Koo, Bon-Min;Byun, Kuen-Joo;Song, Ha-Won
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.11a
    • /
    • pp.773-776
    • /
    • 2004
  • The so-called Life Cycle Cost (LCC) analysis on reinforced concrete bridge can provide useful information for initial design and maintenance plan of the RC bridge. This paper proposes an LCC prediction equation and a sensitivity analysis method for RC bridges. An LCC equation for the RC bridge which includes initial investment cost, maintenance cost, and demolition cost was derived and verified from the data for design and construction of an RC slab bridge. In order to solve uncertainty problem on actual discount rate and material characteristics in the analysis of LCC of concrete bridges, a sensitivity analysis method on the LCC using the Monte Carlo simulation technique was suggested.

  • PDF