• Title/Summary/Keyword: cost minimization

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An Application of the Monte Carlo Method to the Economical Circuit Design in Consideration of the Drift Reliability (표류신뢰도를 고려한 경제적 회로 설계에 대한 몬테칼로법의 적용)

  • Kyun-Hyon Tchah
    • 전기의세계
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    • v.24 no.5
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    • pp.72-80
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    • 1975
  • In this paper an application of the Monte Carlo method to optimum circuit design is discussed. T. Tsuda and T. Kiyono's algorithm based on the Monte Carlo method for solving multiple simul-taneous nonlinear equations is generalized to apply it to finding solutions of the constrained nonlinear optimization problem. The generalized algorithm derived here is directly applied to economical circuit design. In the cirsuit design, the object function is a cost function which is related to the cost of each circuit component. The constraint is the variance of the total system expressed by the variances of each circuit component. The design is to be determined so that the circuit has specified drift reliability with minimum cost. A practical example of economical circuit design and a general nonlinear function minimization is presented with food results.

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Collaborative Procurement System for IT-Enhanced Supply Chains (정보기술을 활용한 공급 사슬의 협업적 조달 시스템에 관한 연구)

  • Eungab Kim;Chankwon Park;Kitae Shin
    • The Journal of Society for e-Business Studies
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    • v.7 no.2
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    • pp.129-141
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    • 2002
  • This paper deals with the collaborative procurement process in a two-echelon supply chain that a manufacturing company and a contractor are connected through the information system. The real time information about inventory and production processing becomes available through this information system. We raise two issues related to the collaborative procurement process. First, we propose a VMI(Vendor-Managed Inventory) type of the procurement policy which focuses on the cost minimization for the total supply chain rather than individual companies. Second, based on the simulation study, we demonstrate that a collaborative procurement process is more cost-effective over classical procurement processes such as (Q, r). The result obtained in this paper can be applied to the quantitative evaluation of the cost saving effect when companies build the information sharing based, collaborative procurement system.

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Reliability-Based Optimization using Sensitivity Analysis of Reliability Index (신뢰성 지수의 민감도 해석을 이용한 신뢰성에 기초한 최적설계)

  • 조효남;민대홍;권우성
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.10a
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    • pp.101-108
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    • 2000
  • An optimum design algorithm using efficient reanalysis is proposed for reliability-based optimization problems formulated as the minimization of initial cost and expected failure cost with reliability constraints. The reliability-based optimization is high cost to evaluate objective function and constraints needed reliability analysis. Therefore the sensitivity analysis of reliability index for approximated reanalysis is necessary. In this paper, three solution approaches are suggested and tested. The approaches include : (1) sensitivity analysis using finite difference; (2) sensitivity analysis using automatic differentiation (AD); and (3) sensitivity analysis with respect to intermediate variables using AD. Numerical example is optimized to show the reliability and effectiveness of the new algorithm.

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Optimum Life Cycle Cost Design of High-Speed Railway Steel Bridges (고속철도 강교량의 총기대비용 최적설계)

  • 조효남;민대홍;조준석
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.10a
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    • pp.109-114
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    • 2000
  • In this paper, an optimum design model for minimizing the life-cycle cost (LCC) of high-speed railway steel bridges is proposed The point is that it takes into account service life process as a whole, and thus the life-cycle costs include initial (design, testing, and construction) costs, maintenance costs, expected strength failure costs and expected serviceability failure costs. The problem is formulated as that of minimization of expected total life-cycle cost with respect to the design variables. By processing the optimum LCC design the effective and rational basis is proposed for calculating the total LCC and the sensitivity analysis of LCC is peformed. Based on a numerical example, it may be positively stated that the optimum LCC design of high-speed railway steel bridges proposed in this study provides a lot more rational and economical design, and thus the proposed approach will expedite the development of new concepts and design methodologies that may have important implications in the next generation performance-based design codes and standards.

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Edge Detection Using an Ant System Algorithm (개미 시스템 알고리듬을 이용한 윤곽선 검출)

  • 이성열;이창훈
    • Journal of Korea Society of Industrial Information Systems
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    • v.8 no.4
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    • pp.38-45
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    • 2003
  • This paper presents a meta-heuristic solution technique, Ant System (AS)algerian to solve edge detection problem. We define the quality of edge in terms of dissimilarity, continuity, thickness and length. We cast edge detection as a problem in cost minimization. This is achieved by the formulation of a cost function that inversely evaluates the quality of edge configuration. Twelve windows for enhancing dissimilarity regions based on the valid edge structures are used. The AS algorithm finds the optimal set of edge pixels based on the cost function. The experimental results show that the properly reduced set of edge pixels could be found regardless how complicated the image is.

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An efficient dynamic routing scheme for delay-bounded multicasting

  • Kang, Moon-Sik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.12
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    • pp.2626-2634
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    • 1997
  • The purpose of multicasting is to reduce the network costs for transmitting the same traffic to multiple destinations. In this paper, an efficient delay-bounded multicasting routing algorithm is proposed, which satistifies the network conditions of cost minimization and can adjust the dynamic events, such as 'leave and/or join ones' from the multicast group. Also, our algorithm is designed for various network requirements such as the efficiet dynamic group support, high-quality data distribution, and adaptability to variable situation. After the delay tolerance and the maximum group size are determined according to network state and requirements for delay and cost, the dynamic delay-bounded multicast tree is constructed using partial multicast routing. We evaluate the performance of the proposed algorithm by running simulations on randomly generated test networks using a Sun Sparc 20 workstation. We were able to obtain good simulation resutls, which means solutions that lies between the minimum cost solution and the minimum delay one.

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A Study on the Minimization of Generation Cost of an Individual Power Generation Considering Available Transfer Capability(ATC) (가용송전용량을 고려한 각 발전회사의 발전비용 최소화 기법 개발에 관한 연구)

  • Jeong, Sung-Won;Gim, Jae-Hveon
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.12
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    • pp.586-591
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    • 2005
  • This paper presents a method of minimizing of generation cost on individual electrical power utility. The method is based on the Economic Dispatch (ED) and linear Available Transfer Capability (ATC). The economic dispatch redistributes the total load to individual units to minimize the generation cost without transmission network constraints. The proposed method is implemented using ATC calculated from Power Transfer Distribution Factor (PTDF) for the transmission network constraints. The performance of the proposed method has been tested for the IEEE-30 bus system. It has also been observed that the results of the proposed method is compared with that of optimal power flow.

Optimal Operation of Reactive Power Compensation Devices for Voltage Control of Emegency Status (비상상태 전압제어를 위한 무효전력보상설비의 최적 운용)

  • Ahn, Chang-Han;Baek, Young-Sik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.5
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    • pp.661-666
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    • 2015
  • This paper proposes a method for solving running cost problem by minimizing switching reactive power compensation devices. An objective function was modeled by calculating the weighting value of cost, and a solution was derived using ILP. This paper suggests optimal coordinative control method between FACTS, Shunt Reactors, Capacitors and OLTC. Therefore, it is valuable for decision maker in determining order and capacity of devices which gaining a voltage stabilization. As a result, the objectives of voltage stabilization and cost minimization were achieved simultaneously. This realizes the economic efficiency of the system. We start by showing how to solve systems of linear equations using the language of pivots and tableaus. The effectiveness of this technique is demonstrated in modified PSS/E MIGUM 45 bus system. The simulation results show the effectiveness of this algorithm by comparing the outcome withseveral established methods.

A Study on Optimal Lead Time Selection Measures of the Construction Materials (건설자재의 적정 리드타임 산정에 관한 연구)

  • Lee, Sang-Beom
    • Journal of the Korea Institute of Building Construction
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    • v.4 no.1
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    • pp.105-110
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    • 2004
  • Resource procurement is an important management area because cost of resource covers 40% of total construction project cost and resource delivery has direct relationship with project performance. Integration of cost provides various potentials for effective and efficient project control. This study investigates the usefulness of time in resource procurement management focused on materials. These days, construction projects have characterized manufacture because of industrialization and component. Therefore, application of systematic resource planning has been requested in the construction. There are many companies conducting procurement of resource on the web by applying MRP, ERP etc. in the construction. However, in applying them in the construction yet, there is obstruction. MRP has the character doing its function under accurate cost prediction of resource. But prediction of resource is difficult in industry mechanism of the construction. If accurate cost prediction of resource is possible in the construction, it will be expected to reduce cost of procurement of resource substantially by applying successful resource planning model in the manufacture. On the basis of recent current, the purpose of study is to present procurement of resource system that period observance of construction and minimization of stock is possible by reflecting accurate lead-time to apply proactive thought to be able to cope with alteration of construction schedule efficiently in analyzing resource planning of the construction site.

A Dual-Population Memetic Algorithm for Minimizing Total Cost of Multi-Mode Resource-Constrained Project Scheduling

  • Chen, Zhi-Jie;Chyu, Chiuh-Cheng
    • Industrial Engineering and Management Systems
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    • v.9 no.2
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    • pp.70-79
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    • 2010
  • Makespan and cost minimization are two important factors in project investment. This paper considers a multi-mode resource-constrained project scheduling problem with the objective of minimizing costs, subject to a deadline constraint. A number of studies have focused on minimizing makespan or resource availability cost with a specified deadline. This problem assumes a fixed cost for the availability of each renewable resource per period, and the project cost to be minimized is the sum of the variable cost associated with the execution mode of each activity. The presented memetic algorithm (MA) consists of three features: (1) a truncated branch and bound heuristic that serves as effective preprocessing in forming the initial population; (2) a strategy that maintains two populations, which respectively store deadline-feasible and infeasible solutions, enabling the MA to explore quality solutions in a broader resource-feasible space; (3) a repair-and-improvement local search scheme that refines each offspring and updates the two populations. The MA is tested via ProGen generated instances with problem sizes of 18, 20, and 30. The experimental results indicate that the MA performs exceptionally well in both effectiveness and efficiency using the optimal solutions or the current best solutions for the comparison standard.