• KIEAE Journal
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• v.15 no.5
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• pp.21-33
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• 2015

Purpose: Domestically, a recent controversial part on Mixed-Use Development is its case that utilizes railroad sites among urban infrastructure. but most of all, a concern is being concentrated on the Mixed-Use Development that uses railroad depot. It has the advantage, which can give diversity and publicness to urban environment by using and planing the upper and bottom of railroad depot, a proximity site as Development Available Land. However, there are few cases except for only Yang-cheon APT in SinJeong railway depot as a domestic case even though a domestic concern about Mixed-Use Development is rising more than ever. Method: Accordingly, this study has something in common with a domestic case, dealing with a case of development in Hongkong that enhances efficiency for city space through Mixed-Use Development and solves various urban problems. Result: A purpose of this study, based on overall comprehension about Rail and Property Model of MTRC in Hongkong, is to figure out how it solve various problems in Mixed-Use Development using Railway Depot or stations in the base of Rail and Property Model of MTRC.

• Journal of Korean Society of Transportation
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• v.21 no.4
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• pp.113-132
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• 2003

Using nonradial data envelopment analysis(DEA) under assumptions of strong disposability and variable returns scale, this paper annually estimates productive. technical and allocative efficiencies of three publicly-owned rail transit properties which are different in terms of organizational type: Seoul Subway Corporation(SSC, local public corporation), the Seoul Metropolitan Electrified Railways sector (SMESRS) of Korea National Railroad(the national railway operator controlled by the Ministry of Construction and Transportation(MOCT)), and Busan Urban Transit Authority (BUTA, the national authority controlled by MOCT). Using the estimation results of Tobit regression analysis. the paper next computes their true productive, true technical and true allocative efficiencies, which reflect only the impacts of internal factors such as production activity by removing the impacts of external factors such as an organizational type and a track utilization rate. And the paper also computes an organizational efficiency and annually gross efficiencies for each property. The paper then conceptualized that the property produces a single output(car-kilometers) using four inputs(labor, electricity, car & maintenance and track) and uses unbalanced panel data consisted of annual observations on SSC, SMESRS and BUTA. The results obtained from DEA show that, on an average, SSC is the most efficient property on the productive and allocative sides, while SMESRS is the most technically-efficient one. On the other hand. BUTA is the most efficient one on the truly-productive and allocative sides, while SMESRS on the truly-technical side. Another important result is that the differences in true efficiency estimates among the three properties are considerably smaller than those in efficiency estimates. Besides. the most cost-efficient organizational type appears to be a local public corporation represented by SSC, which is also the most grossly-efficient property. These results suggest that a measure to sort out the impacts of external factors on the efficiency of rail transit properties is required to assess fairly it, and that a measure to restructure (establish) an existing(a new) rail transit property into a local public corporation(or authority) is required to improve its cost efficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.9
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• pp.791-795
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• 2000

Amorphous chalcogenide glasses have a wide variety of light-induced effects. In this study, we have investigated the diffraction efficiency of chalcogenide. As$_{40}$ Ge$_{10}$ Se$_{15}$ S$_{35}$ thin films by the various applied electric fields. The holographic grating in these thin films has been formed using a linearly polarized He-Ne laser light (633nm). The diffraction efficiency was investigated the two method of applied electric field in the perpendicular and parallel to the direction of inducing beam. We obtained that properties of diffraction efficiency in the two methods of applied electric field. The result is shown that the diffraction efficiency of parallel electric field is 285% increase, η=1.1$\times$10$^{-3}$ and the diffraction efficiency of perpendicular electric field is 80% decrease, η=9.83$\times$10$^{-5}$ . Also, we have investigated the anisotropy property on chalcogenide thin films by the electric field effects.

• Steel and Composite Structures
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• v.26 no.2
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• pp.183-196
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• 2018

The traditional prestressed concrete composite box-girders with corrugated steel webs have several drawbacks such as large deflection and potential local buckling. In this study, two methods were investigated to optimize and improve the prestressed concrete composite box-girders with corrugated steel webs. The first method was to replace the concrete bottom slab with a steel plate and the second method was to support the concrete bottom slab on the steel flanges. The behavior of the prestressed concrete composite box-girders with corrugated steel webs with either method was studied by experiments on three specimens. The test results showed that behavior of the optimized and upgraded prestressed concrete composite box-girders with corrugated steel webs, including ultimate bearing capacity, flexural stiffness, and crack resistance, is greatly improved. In addition, the influence of different shear connectors, including perfobond leisten (PBL) and stud shear connectors, on the behavior of prestressed concrete composite box-girders with corrugated steel webs was studied. The results showed that PBL shear connectors can greatly improve the ultimate bearing capacity, flexural stiffness and crack resistance property of the prestressed concrete composite box-girders with corrugated steel webs. However, for the efficiency of prestressing introduced into the girder, the PBL shear connectors do not perform as well as the stud shear connectors.

• Membrane Journal
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• v.26 no.1
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• pp.14-25
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• 2016

The membrane separation process is growing very fast because of the high efficiency and low cost compared with other traditional process. The membrane process consists of various components such as membrane, module and mechanical part. The requirements for materials used in the membrane separation are becoming more and more demanding for achievement of high efficiency. Membrane module is also considered as the one of the key component in the membrane system. Recently composite materials have been considered as the membrane housing due to their excellent property and low cost compared with stainless module. In this review, a various types of glass fiber and composite material are summarized and their potential for the application of membrane system is discussed.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.2
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• pp.201-212
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• 2007

Genetic algorithms (GAs) are very useful methods for global search and have been applied to various optimization problems. They have two kinds of important search mechanisms, crossover and mutation. Because the performance of GAs depends on these operators, a large number of operators have been developed for improving the performance of GAs. Especially, many researchers have been more interested in a crossover operator than a mutation operator. The reason is that a crossover operator is a main search operator in GAs and it has a more effect on the search performance. So, we also focus on a crossover operator. In this paper we first investigate the drawback of various crossovers, especially subtour-based crossovers and then introduce a new crossover operator to avoid such drawback and to increase efficiency. Also we compare it with several crossover operators for symmetric traveling salesman problem (STSP) for showing the performance of the proposed crossover. Finally, we introduce an efficient simple hybrid genetic algorithm using the proposed operator and then the quality and efficiency of the obtained results are discussed.

• Fashion & Textile Research Journal
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• v.16 no.2
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• pp.312-318
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• 2014

This study examined the correlation between a handle evaluation of cosmetic puff textile and a sensory evaluation. The KES-F system was used to analyze the main mechanical factors for the handle evaluation and a statistical method was used for the sensory evaluation. The results revealed different mechanical properties and handle values of the tested cosmetic puff textiles. A material type and structure of the cosmetic textile affected the handle property of the material which is the most important factor for a cosmetic purpose. Particularly, the physical properties of textile material are likely to be important factors for the sensory property of cosmetic material. In addition, the sensory evaluation also revealed different sensory characteristics of the cosmetic efficiency according to the cosmetic puff textile. No close relationship was observed between the mechanical properties and sensory evaluation on the cosmetic puff textiles. The sensory evaluation of a cosmetic efficiency is not only decided by the physical and mechanical characteristics of the cosmetic textile material. Overall, when using textiles used for the cosmetic purposes, it is important to consider not only the proper mechanical properties of the textiles but also the use and sensory satisfaction. Development and selection of the cosmetic textiles should be focused on both the material function and consumer satisfaction.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.499-504
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• 2006

To improve the quality of coating paper, many areas, such as the manufacturing process of inorganic pigment for the coating, the property change of coating color, the surface design of coating pigment and the productivity of coated paper, were studied. In this study the physical properties and printability of coated paper were compared with the coating pigment to modify the surface of large particle and the coating pigment to mix together the large and small particles. After the coating color was mixed under the same conditions in order that the coating color has the same printability, the printability change caused by the surface modification of coating color was investigated. With the surface SEM of coated paper, the efficiency of the surface modification of coating pigment was investigated. The physical property and printability of coated paper, in addition to the physical properties of coating color, were compared and evaluated. Also, the efficiency of printability was evaluated, changing the mixing condition.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.3
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• pp.63-69
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• 1998

In this paper, a new input method is proposed to improve shift-invariant property of a photorefractive correlator andwe implemented real-time optical pattern recognition system using it. In the conventional photorefractive correlator, it is vrey difficult to satisfy the Bragg condition in the pattern recognition process. So, correlation peak is decreased heavily for the shift of input image. If a liquid crystal television(LCTV) without an anlyzer is used as input device, we can get the correlation result regardless of shift of input image because beam path is not changed during storage of holographic filter and correlation process. Also recording time of a holographic matched filter in photorefractive crystal is reduced and the correlation peak is increased because incident beam on the LCTV is transmitted completely. Therefore total optical efficiency is improved. We compared and analyzed the correlation results of proposed photorefractive correlator by computer simulation and optical experiment. We used a BaTiO$_{3}$ single crystal which has high diffraction efficiency in optical experiment.

• Textile Coloration and Finishing
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• v.33 no.1
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• pp.24-30
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• 2021

In this study, PET containing 3% silver ion-exchange zeolite was mixed with cotton in a ratio of 6:4 to prepare a spun yarn to evaluate the tensile strength, absorption speed, absorption rate, antibacterial property, and the efficiency of deodorization. As a result, the following conclusions were obtained. First, it can be confirmed that silver ion exchange zeolite is evenly distributed inside and on the surface of the antimicrobial PET-SF through SEM. It was found that the tensile strength between the CVC sample mixed with silver ion zeolite PET and cotton and the normal cotton 100% sample was slightly lower in the CVC sample. Although the absorption speed and water absorption rate were measured to find out the moisture characteristics, it was confirmed that there was no significant difference. The contact angle was slightly larger in the antimicrobial CVC sample, but the time it took for the moisture to completely penetrate into the knit fabric was 0.85 seconds. In addition, it was found that out of the total mixing ratio, 40% of antibacterial PET was spun with regular cotton to produce yarn, which had an excellent bacteria reduction rate of 99.9% and a deodorization efficiency of 85%.