• Journal of the Korean GEO-environmental Society
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• v.10 no.3
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• pp.29-36
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• 2009

In this paper, a case of a high-rise building supported by a large-diameter drilled shaft socketed in a weathered ground has been studied. The design case of pile foundation presented in this paper could be a representative example of execution of pile design through three(3) design stages of "preliminary design-proof test-supplementary design". As proof test, two(2) BDH PLT (Bi-directional High Pressure Pile Load Test) were performed at the early construction stage. By following the design process of this way, the economic pile design could be carried out and a large amount of construction cost saving could be realized.

• Korean Management Science Review
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• v.27 no.3
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• pp.15-31
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• 2010

We consider a reverse logistics network design problem for recycling. The problem consists of three stages of transportation. In the first stage products are transported from retrieval centers to disassembly centers. In the second stage disassembled modules are transported from disassembly centers to processing centers. Finally, in the third stage modules are transported from either processing centers or a supplier to a manufacturer, a recycling site, or a disposal site. The objective is to design a network which minimizes the total transportation cost. We design a cooperative coevolutionary algorithm to solve the problem. First, the problem is decomposed into three subproblems each of which corresponds to a stage of transportation. For subproblems 1 and 2, a population of chromosomes is constructed. Each chromosome in the population is coded as a permutation of integers and an algorithm which decodes a chromosome is suggested. For subproblem 3, an heuristic algorithm is utilized. Then, a performance evaluation procedure is suggested which combines the chromosomes from each of two populations and the heuristic algorithm for subproblem 3. An experiment was carried out using test problems. The experiments showed that the cooperative coevolutionary algorithm generally tends to show better performances than the previous genetic algorithm as the problem size gets larger.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.1
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• pp.57-62
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• 2009

This paper deals with the optimal design of a shield plate in order to minimize Extremely-Low-Frequency(ELF) magnetic fields generated from three-phase bus bars. Combining an evolutionary strategy with a 3D finite element analysis tool, the main dimensions of the shield plate are sought out. The optimization procedure consists of two separated design stages to take into account all foreseen structures of the plate. In the first stage, the basic dimensions of the plate are optimized including the distance between the plate and the bus bars. Then the usefulness of the additional structures such as a slit and fillet is investigated in the second stage. Finally the optimum design of the shield plate is suggested from the viewpoint of the shielding effectiveness and manufacturing cost.

• IE interfaces
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• v.9 no.3
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• pp.236-248
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• 1996

Most of business enterprises today struggle with the coordination of work which is one of the most challenging problems in the business environment. And the situation becomes worse by the increasing complexity and uncertainty. In this paper, suitability of workflow technology for the modelling, optimization, and automation in the complex business structures is discussed. Also, in the abscence of a fully fledged method for analysis and design of workflow systems, this paper proposes a method, ETM(Extended Trigger Modelling), which can solve several problems in other methods. The proposed ETM approach consists of three stages such as situation analysis stage, activity coordination stage and implementation preparation stage. A modelling case of the proposed procedure is also presented.

• Computers and Concrete
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• v.32 no.2
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• pp.185-206
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• 2023

This article aimed to explore the optimization of mineral admixtures and retarding admixture for high-performance concrete. In essence, fresh concrete can be regarded as a mixture in which both coarse and fine aggregates are suspended in a cement-based matrix paste. Based on this view, the test procedure was divided into three progressive stages of binder paste, mortar, and concrete to explore their rheological behavior and mechanical properties respectively. At each stage, there were four experimental control factors, and each factor had three levels. In order to reduce the workload of the experiment, the Taguchi method with an L9(3⁴) orthogonal array and four controllable three-level factors was adopted. The test results show that the use of the Taguchi method effectively optimized the composition of high-performance concrete. The slump of the prepared concrete was above 18 cm, and the slump flow was above 50 cm, indicating that it had good workability. On the other hand, the 28-day compressive strength of the hardened concretes was between 31.3-59.8 MPa. Furthermore, the analysis of variance (ANOVA) results showed that the most significant factor affecting the initial setting time of the fresh concretes was the retarder dosage, and its contribution percentage was 62.66%. On the other hand, the ANOVA results show that the most significant factor affecting the 28-day compressive strength of the hardened concretes was the water to binder ratio, and its contribution percentage was 79.05%.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.3
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• pp.457-467
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• 2015

The demand for coverall-type protective clothing are increasing in many industrial fields; however, it is impossible to evaluate the wearers' apparel fit because there is no commercialized pattern in the market. This study produces a manual for the process of acquiring patterns by separating PPE products into pieces to provide information on acquiring patterns. The analysis was on coverall-type non woven protective clothing in the domestic market, and 4 panels examined the validity, reliability, and efficiency of various possible methods on each step of process. Five steps were conducted to acquire patterns removing wrinkles, marking seams lines, separating seams, and pattern completing. The process of converting these into pattern files was designed through three procedures of digitizing, editing, and exporting and detailed stages. Fitting tests were undertaken, real patterns by actual modeling and pattern files by virtual modeling; all showed similar forms with outfits wearing ready-made protective coveralls. This study sought the most efficient and objective method of virtual modeling and proposed it as a manual. It is expected for the pattern reverse-designing manual through products analysis presented in this study that would be a helpful addition of information to the pattern tracing of pattern-less clothing products.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.6
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• pp.964-978
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• 2015

Numerous experiments with a scaled pilot facility were carried out to compare the relative bulk transfer performance of three special devices for applications to drilling systems. The pipe diameter for bulk transportation was 3 in., which corresponds to around half of the actual system dimensions. Two different pressures, 3 and 4 bar, were considered to check the relative performance under different pressure conditions at a bulk storage tank. And to make a practical estimation method of the bulk transfer rate at the early design stages of the bulk handling system, a series of experiments were conducted for real scaled bulk handing systems of two drilling vessels. The pressure drops at each pipe element as well as the bulk transfer rates were measured under different operating conditions. Using the measured results, the friction factor for each pipe element was calculated and a procedure for transfer rate estimation was developed. Compared to the measured transfer rate results for other drilling vessels, the estimated transfer rates were within a maximum 15% error bound.

• Journal of Practical Engineering Education
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• v.11 no.2
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• pp.159-165
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• 2019

Engineering design education has been established and implemented as three stages of basic design, element design, and capstone design with the introduction of engineering education accreditation system. In the basic design, the concept and procedure of design is introduced to the beginners of engineering, and the creativity and teamwork is practiced rather than mathematical detailed design for the purpose of being connected to and used effectively in the capstone design. In this study, the opinions of the students performing capstone design after taking basic design were surveyed through questionnaire. Overall, students recognize the importance of basic design education and experienced that it is useful. The results indicate that effective basic engineering design education is being carried out, and are considerably agree to those at the professors in the former survey.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.5 no.3
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• pp.200-205
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• 2005

The objectives of this study were to introduce the easiest and most proper applications of datamining in industrial processes. Applying datamining in manufacturing is very different from applying it in marketing. Misapplication of datamining in manufacturing system results in significant problems. Therefore, it is very important to determine the best procedure and technique in advance. In previous studies, related literature has been introduced, but there has not been much description of datamining applications. Research has not often referred to descriptions of particular examples dealing with application problems in manufacturing. In this study, a datamining roadmap was proposed to support datamining applications for industrial processes. The roadmap was classified into three stages, and each stage was categorized into reasonable classes according to the datamining purposed. Each category includes representative techniques for datamining that have been broadly applied over decades. Those techniques differ according to developers and application purposes; however, in this paper, exemplary methods are described. Based on the datamining roadmap, nonexperts can determine procedures and techniques for datamining in their applications.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.43-53
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• 2016

The purpose of this study is to examine the meaningfulness and the possibility of developing kinetic narrative educational contents based on English literature with convergent approaches. To accomplish the objective, this paper examines three areas of research such as kinetic education, English literature education, and total physical response-storytelling method. It introduces the following three stages of development procedure: 1) selecting and analyzing English literature, 2) designing a prototype including the story flow, the movement and the motion interaction design, and 3) constructing motion database using Laban movement analysis. Then, how to apply it to young learners is illustrated with 'the story of the three little pigs,' Finally, implication for the field of young learner English education and English literature is discussed.