• Journal of KSNVE
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• v.5 no.1
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• pp.29-35
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• 1995

This paper presents the simultaneous optimal design of structure and LQG control systems for the improvement of riding comforts of active vehicle suspension systems. The performance index of riding comforts is extended to include frequency-weighted acceleration in the quadratic cost functional. Janeway human response curve with respect to acceleration is used to verify the usefulness of the presented method. The method is applied to a half model of an active vehicle suspension systems with elastic body moving on randomly profiled road. The values of stiffness of suspensions are used for the structural design variables. The conjugate gradient method is used for optimization. The simulated results of simultaneous optimization with frequency-weighted cost functional are compared with those without frequency- weighted cost functional.

• The Mathematical Education
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• v.43 no.2
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• pp.177-186
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• 2004

In this paper, we introduce new functional definitions for school geometry based on DGS (dynamic geometry system) teaching-learning environment. For the vertices forming a geometric figure, we first consider the relationship between the independent vertices and dependent vertices, and using this relationship and educational considerations in DGS, we introduce functional definitions for the geometric figures in terms of its independent vertices. For this purpose, we design a new DGS called JavaMAL MicroWorld. Based on the needs of new definitions in DGS environment for the student's construction activities in learning geometry, we also design a new DGS based geometry curriculum in which the definitions of the school geometry are newly defined and reconnected in a new way. Using these funct onal definitions, we have taught the new geometry contents emphasizing the sequential expressions for the student's geometric activities.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.127-130
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• 2009

Recently agricultural productivity innovation projects are increasing all over the farming countries. To reform and improve the productivity of agricultural industry is important factors. This research is to do the functional Analysis for P-C-M support System Design in Agricultural Facilities. By analyzing the for P-C-M support System modules in the agricultural construction process, P-C-M support System factors are derived and defined. The result of this study would widely be used as a fundamental research guide to develop the agricultural P-C-M support System in the agricultural construction process.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.8
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• pp.689-696
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• 2001

Large-scale Multi-disciplinary Systems(LMS) such as transportation, aerospace, defense etc. are complex systems in which there are many subsystems, interfaces, functions and demanding performance requirements. Because many contractors participate in the development, it is necessary to apply methods of sharing common objectives and communicating design status effectively among all of the stakeholders. The processes and methods of systems engineering which includes system requirement analysis; functional analysis; architecting; system analysis; interface control; and system specification development provide a success-oriented disciplined approach to the project. This paper shows not only the methodology and the results of model-based systems engineering to Automated Guided Transit(AGT) system as one of LMS systems, but also propose the extension of the model-based tool to help manage a project by linking WBS (Work Breakdown Structure), work organization, and PBS (Product Breakdown Structure). In performing the model-based functional analysis, the focus was on the operation concept of an example rail system at the top-level and the propulsion/braking function, a key function of the modern automated rail system. The model-based behavior analysis approach that applies a discrete-event simulation method facilitates the system functional definition and the test and verification activities. The first application of computer-aided tool, RDD-100, in the railway industry demonstrates the capability to model product design knowledge and decisions concerning key issues such as the rationale for architecting the top-level system. The model-based product design knowledge will be essential in integrating the follow-on life-cycle phase activities. production through operation and support, over the life of the AGT system. Additionally, when a new generation train system is required, the reuse of the model-based database can increase the system design productivity and effectiveness significantly.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.3
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• pp.47-59
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• 2008

The recent trend of Sports Wear is seeking functionality and fashion at the same time, where the spread of sportism becomes caual style leading street fashion. Sports Wear is classified into active Sports Wear and Sports casual Wear, in which active Sports Wear is expanded to a mixture with Sports casual wear. The purpose of this study is to research the trend of materials used in active Sports Wear and Sports casual wear. Materials used for jacket/jumper, pants and t-shirts of active Sports Wear and Sports casual wear, and high-tech functional materials used for active Sports Wear have been analyzed. The results of the study are the following: a) Most of the materials used for Sports Wear are polyester, nylon, cotton, and a mixture of cotton and polyester. Active Sports Wear uses functional materials and texture such as Dri-Fit, which absorbs and dries fast, whereas Sports casual wear satin, cire and denim has been used to keep up with the trend rather than focusing in functionality: b) companies such as Nike and Adidas have used many high-tech materials to emphasize the functionality of Sports Wear, while Puma stresses on fashion rather than function, however uses spandex in order for the consumer to feel comfortable during physical activities; c) active Sports Wear in jacket/jumper, pants and t-shirts uses functional material and texture, however Sports casual wear uses satin and cire to keep up with the fashion trend rather than functionality; d) and Nike uses high-tech funtional materials for its Sports Wear in therma-fit, Clima-fit, Dri-fit and storm-fit, whereas Adidas uses Clirna-lite, Clirna-proof, Clima-warm, and Clirna-cool in their active Sports Wear.

• The Journal of Sustainable Design and Educational Environment Research
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• v.6 no.2
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• pp.1-24
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• 2007

The knowledge-based 21st century requires lifelong education for the development of qualification of man's life and self-development. Schools are considered a place of lifelong education due to easy access to human resources as well as facilities. Furthermore, schools need a more multi-functional openness in order to lead lifelong education of the local society. Jeju schools are in the early stages of creating multi-functional facilities to meet to the needs of the knowledge-based 21st century. In order to bring change into the local school s, this needs to be solved. therefore, the purpose of this research is to complement the elements to needed to open schools, project, management, and operation of multi-functional facilities, so that schools can play a role In lifelong education. To achieve this purpose, this research examined programs and the area of lifelong education at schools through investigating documents on the definition of local society and lifelong education, and analyzed the relationship of schools and local society, and public access of schools' facilities. The results of this study are summarized as follows; 1) Comparing to traditional middle and high school facilities, it occurs various types of plane and the area is somewhat expanded in the school with same class size, however, it needs to improve facility standards in its reality to deal with the change of future educational environment actively. 2) Spatial composition of educational facilities should functionally designed considering that the characteristics of design process mood. In facilities arrangement of middle and high schools, it shows diverse forms of arrangement from existing uniform straight type, however, most of schools do not being against the simple in their external space. Therefore, it requires an expansion of space size and facilities for the change of school life outside class.

• Journal of Korea Multimedia Society
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• v.13 no.1
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• pp.143-152
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• 2010

Because of a rising in the standard of living and the development of medical technology, Korea is expected to become an aging society more than 14% elderly population and the silver generation will be responsible for the large portion of economic activities. The silver generation has relatively diminished in perception, learning, and exercise due to the physical aging. Therefore, it is important the development of game contents which can constantly provide the maintenance function of physical and mental health and the functional exercise with spending the leisure time. In this paper, we suggest a design method for developing the game contents which are able to help the silver generation to strengthen their lower extremities and to enjoy their leisure time. The proposed method will enable to lead the silver generation to carry on the physical activities with the amusement of playing a game through the functional design concepts appropriate for the ability of the silver generation's perception and physical activities, an adaptive game process customized by the individual capability and a user-friendly sensory interface.

• Korean Journal of Materials Research
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• v.30 no.11
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• pp.581-588
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• 2020

Reducing CO₂ into high value fuels and chemicals is considered a great challenge in the 21st century. Efficiently activating CO₂ will lead to an important way to utilize it as a resource. This article reviews the latest progress of g-C₃N₄ based catalysts for CO₂ reduction. The different synthetic methods of g-C₃N₄ are briefly discussed. Article mainly introduces methods of g-C₃N₄ shape control, element doping, and use of oxide compounds to modify g-C₃N₄. Modified g-C₃N₄ has more reactive sites, which can significantly reduce the probability of photogenerated electron hole recombination and improve the performance of photocatalytic CO₂ reduction. Considering the literature, the hydrothermal method is widely used because of its simple equipment and process and easy control of reaction conditions. It is foreseeable that hydrothermal technology will continue to innovate and usher in a new period of development. Finally, the prospect of a future reduction of CO₂ by g-C₃N₄-based catalysts is predicted.

• Journal of the Korean Ceramic Society
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• v.56 no.3
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• pp.284-290
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• 2019

Ternary MoS₂/graphene (G)-TiO₂ photocatalysts were prepared by a simple hydrothermal method. The morphology, phase structure, band gap, and catalytic properties of the prepared samples were investigated by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, UV-vis spectrophotometry, and Brunauer-Emmett-Teller surface area measurement. The H₂ production efficiency of the prepared catalysts was tested in methanol-water mixture under visible light. MoS₂/G-TiO₂ exhibited the highest activity for photocatalytic H₂ production. For 5 wt.% and 1 wt.% MoS₂ and graphene (5MT-1G), the production rate of H₂ was as high as 1989 µmol^-1h^-1. The catalyst 5MT-1G showed H₂ production activity that was ~ 11.3, 5.6, and 4.1 times higher than those of pure TiO₂, 1GT, and 5MT, respectively. The unique structure and morphology of the MoS₂/G-TiO₂ photocatalyst contributed to its improved hydrogen production efficiency under visible light.

• Korean Journal of Materials Research
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• v.31 no.6
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• pp.345-352
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• 2021

In this study, Ni nanoparticle supported by graphene oxide (GO) (Ni-GO) is successfully synthesized through hydrothermal synthesis and calcination, and Cr(VI) is extracted from aqueous solution. The morphology and structure of Ni-GO composites are characterized by scanning electron microscopy (SEM), trans mission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). High-resolution transmission electron microscopy (HRTEM) and XRD confirms the high dispersion of Ni nanoparticle after support by GO. Loading Ni on GO can obviously enhance the stability of Ni-GO composites. It can be calculated from TGA that the mass percentage of Ni is about 60.67 %. The effects of initial pH and reaction time on Cr(VI) removal ability of Ni-GO are investigated. The results indicate that the removal efficiency of Cr(VI) is greater than that of bared GO. Ni-GO shows fast removal capacity for Cr(VI) (<25 min) with high removal efficiency. Dynamic experiments show that the removal process conforms to the quasi-second order model of adsorption, which indicates that the rate control step of the removal process is chemical adsorption. The removal capacity increases with the increase of temperature, indicating that the reaction of Cr(VI) on Ni-GO composites is endothermic and spontaneous. Combined with tests and characterization, the mechanism of Cr(VI) removal by rapidly adsorption on the surface of Ni-GO and reduction by Ni nanoparticle is investigated. The above results show that Ni-GO can be used as a potential remediation agent for Cr(VI)-contaminated groundwater.