• Title/Summary/Keyword: engineering optimization

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A Study on Genetic Algorithm and Stereo Matching for Object Depth Recognition (물체의 위치 인식을 위한 유전 알고리즘과 스테레오 정합에 관한 연구)

  • Hong, Seok-Keun;Cho, Seok-Je
    • Journal of Navigation and Port Research
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    • v.32 no.5
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    • pp.355-361
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    • 2008
  • Stereo matching is one of the most active research areas in computer vision. In this paper, we propose a stereo matching scheme using genetic algorithm for object depth recognition. The proposed approach considers the matching environment as an optimization problem and finds the optimal solution by using an evolutionary strategy. Accordingly, genetic operators are adapted for the circumstances of stereo matching. An individual is a disparity set. Horizontal pixel line of image is considered as a chromosome. A cost function is composed of certain constraints which are commonly used in stereo matching. Since the cost function consists of intensity, similarity and disparity smoothness, the matching process is considered at the same time in each generation. The LoG(Laplacian of Gaussian) edge is extracted and used in the determination of the chromosome. We validate our approach with experimental results on stereo images.

PC Cluster Based Parallel Genetic Algorithm-Tabu Search for Service Restoration of Distribution Systems (PC 클러스터 기반 병렬 유전 알고리즘-타부 탐색을 이용한 배전계통 고장 복구)

  • Mun Kyeong-Jun;Lee Hwa-Seok;Park June Ho
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.54 no.8
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    • pp.375-387
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    • 2005
  • This paper presents an application of parallel Genetic Algorithm-Tabu Search (GA-TS) algorithm to search an optimal solution of a service restoration in distribution systems. The main objective of service restoration of distribution systems is, when a fault or overload occurs, to restore as much load as possible by transferring the do-energized load in the out of service area via network reconfiguration to the appropriate adjacent feeders at minimum operational cost without violating operating constraints, which is a combinatorial optimization problem. This problem has many constraints with many local minima to solve the optimal switch position. This paper develops parallel GA-TS algorithm for service restoration of distribution systems. In parallel GA-TS, GA operators are executed for each processor. To prevent solutions of low fitness from appearing in the next generation, strings below the average fitness are saved in the tabu list. If best fitness of the GA is not changed for several generations, TS operators are executed for the upper $10\%$ of the population to enhance the local searching capabilities. With migration operation, best string of each node is transferred to the neighboring node after predetermined iterations are executed. For parallel computing, we developed a PC cluster system consists of 8 PCs. Each PC employs the 2 GHz Pentium IV CPU and is connected with others through ethernet switch based fast ethernet. To show the validity of the proposed method, proposed algorithm has been tested with a practical distribution system in Korea. From the simulation results, we can find that the proposed algorithm is efficient for the distribution system service restoration in terms of the solution quality, speedup, efficiency and computation time.

The Study of Collaborative Work-Flow System Architecture for Optimization of Product Development in Enterprise (기업의 제품 개발업무 최적화를 위한 Collaborative Work-Flow System Architecture 연구)

  • Lee, Jae-Cheol;Bang, Heon;Ahn, Dae-Jung;Kim, Tae-Yun;Lee, Seung-Ho;Ryu, Yeong-Seon;Song, Byeong-Jae;Choi, Yeong-Jun;Ahn, Gye-Ho;Chang, Jeong-Ryeol;Cho, Sang-seok;Ryu Byeon-Gil;Hwang, Chang-Gyu
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2001.10a
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    • pp.25-28
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    • 2001
  • Today enterprises are bringing forward the strong needs for the Global Work Space that is able to realize the collaboration of the virtual enterprise in order to achieve the rapid entrance to market, the quality improvement as well as the cost reduction of their new products. Especially, they are building the efficient Product Management Infrastructure in parallel with the real-time knowledge management for the information generated in the course of a product lifecycle and the Process Innovation making the Concurrent Engineering possible. Building a system in the web environment cannot be the entire effort to realize the Global Work Space within an enterprise that is an essential factor for the reduction of a product development period which in turn contributes to Time to Market. Various work models and processes are found in enterprises and many different application programs are developed and utilized to support these. This study proposes a scheme for the optimized Collaborative Workflow System Architecture that is able to take in and apply various application programs accompanied by the product development work process. Through this, we are to examine various limits and problems existing in the real-time collaborative system between enterprises and to reform these.

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Strength Optimization of Ventilating Container(I)-Experimental Analysis (통기성 상자 구조물의 강도적 최적화 연구(I)-실증 분석)

  • Park, Jong-Min
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.7 no.2
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    • pp.19-24
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    • 2001
  • The design criteria of ventilating container is not provided yet in Korea. This caused strength reduction due to the ventilating hole and bad ventilating performance. The purposes of this study were to survey the present situation of ventilating container in Korea, to analyze the strength reduction on the atmosphere condition variation, and to provide the criteria for the optimum design of ventilating container. The ventilating area of container was $1.41{\sim}2.65%$, and strength reduction due to the varied pattern, size and location of ventilating hole was $8.5{\sim}20.2%$. The effect on the strength reduction from the pattern and location of ventilating hole was bigger than that from the ventilating area. Equilibrium arrival time of temperature and relative humidity was shorter as the ventilating area was bigger, and temperature reached to the equilibrium state earlier than the relative humidity. There was no significant difference on the ventilating hole pattern between equilibrium arrival time of temperature and relative humidity and equilibrium arrival temperature and relative humidity if the ventilating area was the same.

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Parameter-setting-free algorithm to determine the individual sound power levels of noise sources (적응형 파라미터 알고리즘을 이용한 개별 소음원의 음향파워 예측 연구)

  • Mun, Sungho
    • International Journal of Highway Engineering
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    • v.20 no.3
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    • pp.59-64
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    • 2018
  • PURPOSES : We propose a parameter-setting-free harmony-search (PSF-HS) algorithm to determine the individual sound power levels of noise sources in the cases of industrial or road noise environment. METHODS :In terms of using methods, we use PSF-HS algorithm because the optimization parameters cannot be fixed through finding the global minimum. RESULTS:We found that the main advantage of the PSF-HS heuristic algorithm is its ability to find the best global solution of individual sound power levels through a nonlinear complex function, even though the parameters of the original harmony-search (HS) algorithm are not fixed. In an industrial and road environment, high noise exposure is harmful, and can cause nonauditory effects that endanger worker and passenger safety. This study proposes the PSF-HS algorithm for determining the PWL of an individual machine (or vehicle), which is a useful technique for industrial (or road) engineers to identify the dominant noise source in the workplace (or road field testing case). CONCLUSIONS : This study focuses on providing an efficient method to determine sound power levels (PWLs) and the dominant noise source while multiple machines (or vehicles) are operating, for comparison with the results of previous research. This paper can extend the state-of-the-art in a heuristic search algorithm to determine the individual PWLs of machines as well as loud machines (or vehicles), based on the parameter-setting-free harmony-search (PSF-HS) algorithm. This algorithm can be applied into determining the dominant noise sources of several vehicles in the cases of road cross sections and congested housing complex.

Video Coding Method Using Visual Perception Model based on Motion Analysis (움직임 분석 기반의 시각인지 모델을 이용한 비디오 코딩 방법)

  • Oh, Hyung-Suk;Kim, Won-Ha
    • Journal of Broadcast Engineering
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    • v.17 no.2
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    • pp.223-236
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    • 2012
  • We develop a video processing method that allows the more advanced human perception oriented video coding. The proposed method necessarily reflects all influences by the rate-distortion based optimization and the human visual perception that is affected by the visual saliency, the limited space-time resolution and the regional moving history. For reflecting the human perceptual effects, we devise an online moving pattern classifier using the Hedge algorithm. Then, we embed the existing visual saliency into the proposed moving patterns so as to establish a human visual perception model. In order to realize the proposed human visual perception model, we extend the conventional foveation filtering method. Compared to the conventional foveation filter only smoothing less stimulus video signals, the developed foveation filter can locally smooth and enhance signals according to the human visual perception without causing any artifacts. Due to signal enhancement, the developed foveation filter more efficiently transfers the bandwidth saved at smoothed signals to the enhanced signals. Performance evaluation verifies that the proposed video processing method satisfies the overall video quality, while improving the perceptual quality by 12%~44%.

Optimization of Reinforced Concrete Frames Subjected to Dynamic Loads (동적 거동을 받는 철근 콘크리트 뼈대 구조의 최적화)

  • Park, Moon Ho;Kim, Sang Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.3
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    • pp.439-452
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    • 1994
  • A method to optimize the cost of R/C frames and an algorithm of the optimal limit state design for R/C frames subjected to dynamic loads are presented. The modal superposition method was used to find the dynamic responses of the frames. Each member of R/C frame is made up of more than two elements and the stiffness matrix and consistent mass matrix of three d.o.f in the node of each element was used to include axial, shear and flexural effects. The objective function to be minimized formulated the cost of materials, steel and concrete, and optimised to satisfy the behaviors of R/C frame and each constraint imposed by the limit state requirements. Both objective function and each constraint are derived in terms of design variables which include the effective depth, beam width, compression and tension steel area, and column shear steel area. A few applications are presented which demonstrate the feasibility, the validity and efficiency of the algorithm for automated optimum design of R/C frames where dynamic behavior is to be considered.

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UHF Sensor Location Optimization for Partial Discharge Signals Detection Method (UHF 센서 위치 최적화로 부분방전 신호 검출 방법)

  • Choi, Mun-Gyu;Cha, Hanju
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.3
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    • pp.409-413
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    • 2014
  • GIS partial discharge that occurred in the UHF band signal is effectively detected by the method to IEC60270 5pc the apparent minimum discharge can be detected over the GIS arrangement of the sensor interior and exterior of the UHF in accordance with the optimized position signal by considering the damping ratio is selected so that the signals can be obtained to be mounted. 362kV, 800kV GIS is installed on the internal and external sensors are UHF band signal attenuation is set by measuring the reference value, but the operation, 170kV case 362kV, 800kV on the basis of the measurement data and to be installed and operated. When 170kV per 1Bay by installing the built-in sensor 1 for detecting a partial discharge signal, But, GIS signal attenuation is large in the case of an internal partial discharge signal is not detected in some cases. Where the attenuation is great UHF signal of the sensor by increasing the quantity of partial discharge signals were acquired to allow relocation. The greater the spacing between the sensor and the sensor is applied simplifies the installation and reduces the cost in terms of maintenance of appropriate optimal position is calculated to detect the partial discharge signal is needed. Thus 170kV GIS signal power attenuation of a partial discharge by measuring the UHF sensor, and by relocating the proper position is calculated in accordance with the sensor signal decay rate and minimize the error of omission in detecting a partial discharge signal was optimized.

The Incremental Cost Matrix Procedure for Locating Repair Service Centers in Multinational Reverse Logistics

  • Chen, Hsin Min;Hsieh, Chih Kuang;Wu, Ming Cheng;Luo, Shin Wei
    • Industrial Engineering and Management Systems
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    • v.8 no.3
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    • pp.194-200
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    • 2009
  • This study provides a heuristic algorithm to solve the locating problem of repair service centers (RSCs). To enhance the customer service level with more satisfaction and quicker responsiveness, the locating problem of RSCs has become one of the important issues in reverse supply chain management. This problem is formulated as a zero-one mixed integer programming in which an exiting distributor will be considered to be an un-capacitated repair service center for the objective of cost-minimizing. Since logistical costs are highly interrelated with the multinational location of distributors and RSCs, the fixed cost for setting a repair service center, variable cost, transportation cost, and exchange rates are considered in this study. Recognizing the selection of un-capacitated RSCs' locations is a combinatorial optimization problem and is a zero-one mixed integer programming with NP-hard complexity, we provide a heuristic algorithm named as incremental cost matrix procedure (ICMP) to simplify the solving procedure. By using the concise and structural cost matrix, ICMP can efficiently screen the potential location with cost advantage and effectively decide which distributor should be a RSC. Results obtained from the numerical experiments conducted in small scale problem have shown the fact that ICMP is an effective and efficient heuristic algorithm for solving the RSCs locating problem. In the future, using the extended ICMP to solve problems with larger industrial scale or problems with congestion effects caused by the variation of customer demand and the restriction of the RSC capacity is worth a further investigation.

Design and Analysis of TSK Fuzzy Inference System using Clustering Method (클러스터링 방법을 이용한 TSK 퍼지추론 시스템의 설계 및 해석)

  • Oh, Sung-Kwun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.7 no.3
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    • pp.132-136
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    • 2014
  • We introduce a new architecture of TSK-based fuzzy inference system. The proposed model used fuzzy c-means clustering method(FCM) for efficient disposal of data. The premise part of fuzzy rules don't assume any membership function such as triangular, gaussian, ellipsoidal because we construct the premise part of fuzzy rules using FCM. As a result, we can reduce to architecture of model. In this paper, we are able to use four types of polynomials as consequence part of fuzzy rules such as simplified, linear, quadratic, modified quadratic. Weighed Least Square Estimator are used to estimates the coefficients of polynomial. The proposed model is evaluated with the use of Boston housing data called Machine Learning dataset.