• Title/Summary/Keyword: Structural cost

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Optimum design of partially prestressed concrete beams using Genetic Algorithms

  • Turkeli, Erdem;O zturk, Hasan Tahsin
    • Structural Engineering and Mechanics
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    • v.64 no.5
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    • pp.579-589
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    • 2017
  • This paper deals with the optimum cost design of partially prestressed concrete I crosssectioned beams by using Genetic Algorithms. For this purpose, the optimum cost design of two selected example problems that have different characteristics in behavior are performed via Genetic Algorithms by determining their objective functions, design variables and constraints. The results obtained from the technical literature are compared with the ones obtained from this study. The interpretation of the results show that the design of partially prestressed concrete I crossectioned beams from cost point of view by using Genetic Algorithms is 35~50 % more economical than the traditional ones (technical literature) without conceding safety.

Design optimization of reinforced concrete structures

  • Guerra, Andres;Kiousis, Panos D.
    • Computers and Concrete
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    • v.3 no.5
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    • pp.313-334
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    • 2006
  • A novel formulation aiming to achieve optimal design of reinforced concrete (RC) structures is presented here. Optimal sizing and reinforcing for beam and column members in multi-bay and multistory RC structures incorporates optimal stiffness correlation among all structural members and results in cost savings over typical-practice design solutions. A Nonlinear Programming algorithm searches for a minimum cost solution that satisfies ACI 2005 code requirements for axial and flexural loads. Material and labor costs for forming and placing concrete and steel are incorporated as a function of member size using RS Means 2005 cost data. Successful implementation demonstrates the abilities and performance of MATLAB's (The Mathworks, Inc.) Sequential Quadratic Programming algorithm for the design optimization of RC structures. A number of examples are presented that demonstrate the ability of this formulation to achieve optimal designs.

Study on Modularization of Components for Cost Reduction of Sail Yacht Steering System

  • Kim, Young-Hun
    • Journal of Ocean Engineering and Technology
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    • v.34 no.6
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    • pp.469-474
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    • 2020
  • This study aims to improve the price competitiveness of a steering system with a relatively high cost portion among sail yacht components. Hence, the components of the steering system were analyzed, and steering system modularization was proposed. The fabrication processes before and after the application of modularization was presented. For modularization, primary components such as the pedestals and quadrants of the steering system were developed, and the structural safety of the components was reviewed. It was confirmed that the manufacturing cost of the developed steering system decreased by approximately 33% compared with the existing system. The new steering system presented herein is expected to contribute to the localization of components and price competitiveness of sail yachts.

The efforts always will get gains? Risk perception of turnover and cost of changing job affect employee turnover: Evidence from Korea

  • Li, Liang;Elaydi, Salma;Shin, Geon-Cheol;Wei, Kaikai
    • Asia Pacific Journal of Business Review
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    • v.5 no.2
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    • pp.1-18
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    • 2021
  • This present study investigatesed the impact of the team innovation-oriented human resource management (HRM) practices on employees' turnover intention among financial, pharmaceuticals, distribution, and manufacturing industries in Korea. Furthermore, we explored whether risk perception of turnover and the cost of changing job would mediate the relationship between team innovation-oriented human resource management practices with employees' turnover intention in different industries in Korea. To that end, PLS structural equation modeling was used to exam the research hypothesis. We have found that team innovation-oriented HRM practices have a significant impact on employees' turnover intention. Moreover, we have discovered risk perception of turnover and the switching cost of changing job playing mediating role in the relationship of team innovation-oriented HRM practices with turnover intention among different type of industries employee. Lastly, the theoretical implications were discussed based on these findings.

How Much Discrepancy Can Happen from BIM-based Quantity Take?

  • Kim, Seong-Ah;Chin, Sangyoon
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.263-267
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    • 2015
  • Stakeholders of a construction project expect cost savings through fast and accurate cost analysis by performing BIM-based quantity take-off (BQT). However, authors have observed that there can be discrepancies in the results of BQT depending on the level of development (LOD) and modeling methods. In addition, since quantity take-off methods are different depending on the construction work items, the combination of LOD, modeling methods of BIM, features of construction work items can cause serious overestimate or underestimate in BQT results. It is necessary to identify what kind of problems can happen and how those problems can be avoided in various construction work items, since the discrepancy of quantity take-off results has great impact on not only cost analysis but also the determination of contract amount and it can cause claims, poor construction quality, cost overruns, and many others later in the construction project. Therefore, this paper focuses the identification of issues and problems of BQT at each construction work item level based on two categorizations of structural works and interior works.

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A Study on the Economical Design of Apartment House (경제적인 아파트 설계에 대한 연구)

  • 강문영
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.378-384
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    • 1995
  • This paper descrides on the economical design of apartment house. * The optimal problems are made by considering the objective function which minimize the construction cost of frame. * The object functions are taken as the codfficient equations of the cost function for a unit area. * Constraints are the design limits defined by the ultimate flexural strength, the ultimate shear strength. the minimum thickness, and the ratio of steel in accordance with ACI 318-89 Code. * Optimization is achieved by optimum nonlinear GINO(General interactive Optimizer)program. In design examples, it is compared with the optimum design results of apartment house and underground parking lot for structural systems.

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Advances in Materials for Printed Transistors

  • Ong, Beng S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1065-1066
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    • 2008
  • Printed thin-film transistors (TFTs) have received profound interests as an alternative to their silicon counterparts for use in fabricating next-Gen microelectronics by virtue of projected low manufacturing cost and certain salient features (e.g., thin and lightweight characteristics, structural flexibility, etc.) that printed TFTs bring to device architecture. The economic advantages stem from engaging low-cost printing techniques (e.g., screen printing, gravure, flexography, etc.) for deposition and patterning in place of traditionally costly high-vacuum, high-temperature photolithographic processes. To render printing TFTs possible, solution processable materials are necessary.

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A Study on the Method of New Activity Based Cost Management Coping with Changes in the Cost Structure of Real Estate Construction Industry (부동산 건설업의 원가구조 변화에 대응한 공종별 신활동기준 원가관리 기법에 관한 연구)

  • Lee Jeong-Min
    • Korean Journal of Construction Engineering and Management
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    • v.4 no.4 s.16
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    • pp.69-79
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    • 2003
  • About 93$\%$ of domestic teal estate construction firms registered as the end of 2001 recorded net profits of only less than 500 million won(including firms in the red) for the term. As a result of having analyzed the ratios of sales costs and the structural ratios of sales costs for the past 10 years, it was found that there have been great changes in structural ratios of sales costs. Material costs and labor costs have gradually decreased, but outsourcing costs of processing have greatly increased. In order to find activity points which are fundamental to cost control, the methods of new activity based cost management have been pursued. The characteristics of real estate construction industry lie in the fact that contract prices (sales in) are fixed and amounts of profits differ depending on the use of costs. In order to create maximum profits from fixed contract prices, the new activity based cost management has been proposed. The control of operation budgets and management costs is designed to control their schedules and expenses in different respects. Operation budgets ate executed with specific activities and management costs are controlled as a form of material costs, labor costs, out sourcing costs and expenses which are details of expenditure. In order to execute them by using the methods of new activity based cost management, first of all, we have to analyze what activity drivers ale and how much added values such activities can create. It is considered as a method of cost management which is necessary far the survival management of real estate construction industry.

Calculation Model for Function & Cost Score based on Normalization Method in Design VE (정규화 기법 기반의 설계VE 기능 및 비용 점수 산출 모델)

  • Lee, Jongsik
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.4
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    • pp.98-106
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    • 2015
  • VE aims at reduction in a budget, improvement of function, structural safety and quality security for public construction projects. However, there is possibility for the structural safety and quality security review to be insufficient because related regulations are mostly composed of analysis on economic efficiency of design. In addition, due to the misconception about VE as a cost saving methodology, an alternative is being presented which still focuses mainly on cost saving, but with no objective evaluation of function related to cost. In order to improve this, the government adopted the reduction of life cycle cost and proposal of value improvement, and let people specify the cost and function of the original plan versus the alternative plan, and the value changes between them. However, it is written mainly into practical convenience rather than theoretical basis since a specific way is not suggested. The current method sets a different starting point by applying the attributional difference of function and cost. Furthermore, an evaluation standard for correlating is an important element in rational decision making for assessing and choosing an alternative. This paper analyzes the process and method of function & cost scoring when performing VE and suggests a mathematical normalization model in order to support rational decision making when selecting an optimum plan.

Active Vibration Control of Structure using CMAC Neural Network under Earthquake (CMAC 신경망을 이용한 지진시 구조물의 진동제어)

  • 김동현
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.509-514
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    • 2000
  • A structural control algorithm using CMAC(Cerebellar Model Articulation Controller) neural network is proposed Learning rule for CMAC is derived based on cost function. Learning convergence of CMAC is compared with MLNN(Multilayer Neural Network). Numerical examples are shown to verify the proposed control algorithm. Examples show that CMAC can be applicable to structural control with fast learning speed.

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