• International Journal of Concrete Structures and Materials
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• v.6 no.2
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• pp.87-100
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• 2012

The process of selecting a repair material is a typical one of multi-criteria decision-making (MCDM) problems. In this study Analytical Hierarch Process was applied to solve this MCDM problem. Many factors affecting a process to select an optimal repair material can be classified into quantitative and qualitative requirements and this study handled only quantitative items. Quantitative requirements in the optimal selection model for repair material were divided into two parts, namely, the required chemical performance and the required physical performance. The former is composed of alkali-resistance, chloride permeability and electrical resistivity. The latter is composed of compressive strength, tensile strength, adhesive strength, drying shrinkage, elasticity and thermal expansion. The result of the study shows that this method is the useful and rational engineering approach in the problem concerning the selection of one out of many candidate repair materials even if this study was limited to repair material only for chloride-deteriorated concrete.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.172.2-172
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• 2001

We introduce a new stable feedback controller eventually converges to a conventional SDRE(State Dependent Riccati Equation) based optimal (suboptimal) controller. On conventional SDRE, the optimal control input should be obtained by backward integration of the SDRE at each control point. The proposed controller is given by direct forward integration of a proposed SDRE. This fact enables fast computation and easy implementation. On concerning a state dependent system, the proposed controller may be a candidate to the conventional SDRE based optimal controller if the system is slow varying with states. Though the controller is fast and easy to implement it is not able to cope with a fast varying system. We introduce an optimality index, which indicates how far the proposed controller is deviated from the solution of the convectional SDRE. If the index escapes a ...

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.1938-1948
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• 2003

This paper represents that an enhanced genetic algorithm (EGA) is applied to optimal design of a squeeze film damper (SFD) to minimize the maximum transmitted load between the bearing and foundation in the operational speed range. A general genetic algorithm (GA) is well known as a useful global optimization technique for complex and nonlinear optimization problems. The EGA consists of the GA to optimize multi-modal functions and the simplex method to search intensively the candidate solutions by the GA for optimal solutions. The performance of the EGA with a benchmark function is compared to them by the IGA (Immune-Genetic Algorithm) and SQP (Sequential Quadratic Programming). The radius, length and radial clearance of the SFD are defined as the design parameters. The objective function is the minimization of a maximum transmitted load of a flexible rotor system with the nonlinear SFDs in the operating speed range. The effectiveness of the EGA for the optimal design of the SFD is discussed from a numerical example.

• Journal of Soil and Groundwater Environment
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• v.20 no.7
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• pp.13-22
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• 2015

In this study, we have developed the performance evaluation model for the optimal soil remediation technology selection. Performance evaluation model is composed in the evaluation of two steps. In the first stage, the candidate technologies are derived according to the conditions of drilling, type and concentration of pollutants, and the saturated/unsaturated of target site. In the second stage, each individual candidate technology is evaluated by performance evaluation model. The performance evaluation model has 5 groups of evaluation items and 12 evaluation items which have their own evaluation index and their own weights through the AHP approach surveying 40 experts. From the case study of actual design cases, the applicability of the performance evaluation model was confirmed.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.467-471
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• 2009

A road is a fundammental public traffic facility for transporting people and goods. Road designer should determine the best route considering various conditions to minimize environmental bad effect due to road construction and show road functions sufficiently. In this research, we tried to select the optimal route location by comparing candidate routes considering weights of various items such as land use, slope, aspect, land price and so forth. The candidate routes were analyzed and visualized from built data using a GIS software and then compared with the existing route.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.2
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• pp.118-125
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• 1990

An optimal file allocation algorithm which seeks optimal solution of file allocation problem for efficient management and operation of information files in distributed computer system is proposed. Since file allocation time in practical applications that have many computer sites is tool long, the problem size has to be reduced and computation time is improved by using preassignment conditio. A new method which calculate appriasal value for accurrate value for accurrate representation of assigned state is proposed and the selection criteria to candidate nodes for rapid determination of allocation are given. By using selection criteria, file allocation is determined and final appraisal value represent total cost of assigned state.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.836-839
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• 2016

In this paper, we propose a motion estimation method that is important in performance of video encoding. Conventional motion estimation methods have serious problems of low prediction quality and problems of much computation increase. In the paper, we propose a method that reduces unnecessary computations only using optimal candidate points, while keeping prediction quality almost similar to that of the full search. The proposed method takes only 3~5% in computational amount and has decreased prediction quality about 0~0.01dB compared with the fast full search algorithm.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.3
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• pp.195-206
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• 2022

The primary purpose of this study was to analyze assessment factors by identifying and prioritizing live fire shooting area requirements using the AHP (Analytic Hierarchy Process) technique. Derived assessment factors for candidate sites were divided into six categories. Of these, four categories (base-to-range distance, weapon danger area, range terrain, and size) were in the realm of physical geography while the remaining two (land use and proximity to habitation) fell under the general heading of human geography. A case study was also conducted to select several alternative firing ranges using derived factors. The optimal location was analyzed by evaluating the candidate site using each assessment factor. As a result, it was found that assessment factors applying to GIS (Geographic Information System) were able to effectively analyze a suitable location for relocation of the focal training facility, taking into consideration public-safety issues, training requirements, and residents' past and likely future complaints. Through this process, it can prevent the waste of time and effort in determining an optimal location for a live fire shooing range.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.7
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• pp.1732-1739
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• 2013

The identification of haplotypes, which encode SNPs in a single chromosome, makes it possible to perform a haplotype-based association test with diseases. Given a set of genotypes from a population, the process of recovering the haplotypes that explain the genotypes is called haplotype inference. We propose a new preprocessing algorithm for the haplotype inference by pure parsimony (HIPP). The proposed algorithm excludes a large amount of redundant candidate haplotypes by detecting some groups of haplotypes that are dispensable for optimal solutions. For the well-known synthetic and biological data, the experimental results of our method show that our method run much faster than other preprocessing methods. After applying our preprocessing results, the numbers of haplotypes of HIPP solvers are equal to or slightly larger than that of optimal solutions.

• Journal of the Institute of Convergence Signal Processing
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• v.18 no.2
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• pp.62-67
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• 2017

In this paper, we propose a fast motion estimation algorithm which is important in performance of video encoding. Even though so many fast algorithms for motion estimation have been published due to tremendous computational amount of full search algorithm, efforts for reducing computations of motion estimation still remain. In the paper, we propose an algorithm that reduces unnecessary computations only, while keeping prediction quality the same as that of the full search. The proposed algorithm does not calculate block matching error for each candidate directly to find motion vectors but divides the calculation procedure into several steps and calculates partial sum of block errors for candidates with high priority. By doing that, we can find the minimum error point early and get the enhancement of calculation speed by reducing unnecessary computations. The proposed algorithm uses smaller computations than conventional fast search algorithms with the same prediction quality as the full search algorithm.