• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.1-4
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• 2002

The numerical alaysis of optical device, silicabased device, are presented. The purpose of this paper is to simulate and to design a 8-channel optical wavelength division multiplexer(OWDM) based on Mach-Zehnder Interferometer(MZI) with wavelength spacing between channels Δλ=0.8 nm at central wavelength λ=1.55 ${\mu}{\textrm}{m}$. In initial condition fur simulating, we assumed as follows. A channel waveguide is made from silica based P-doped SiO2 core layers in order to coupling with a fiber easily and its core dimension was 6 ${\mu}{\textrm}{m}$$\times$6 ${\mu}{\textrm}{m}$. The core and clad index of channel waveguide were 1.455 and 1.444, separately, at λ=1.55 ${\mu}{\textrm}{m}$. Where, the separation between channel waveguides in coupling region was 3 ${\mu}{\textrm}{m}$. As a result of analysis, a group mode index of channel waveguide was 1.4498370, was gained by Hermite-Gaussian Method(HGM). Also, the channel spacing was determined by the waveguide arm length difference and was Δλ=0.8 nm as like a proposed condition. The central wavelength of a designed-multiplexer was activated about wavelength λ=1.55 ${\mu}{\textrm}{m}$, and we certificated that it can be used to 8-channel optical wavelength division multiplexer/demultiplexer.

• The Journal of Korean Association of Computer Education
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• v.11 no.1
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• pp.47-55
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• 2008

The purpose of this study is finding factors affecting the teachers' use of Edunet and exploring the developmental direction of Edunet which is a web based comprehensive educational information service system. Based on the technology acceptance model and the results of the previous studies, five external and three internal factors influencing the use of Edunet were extracted. The participants were 100, the group of field-assistants who were expected core users in Edunet, and the response of questionnaire was gathered by online survey system. To analyze the collected data and the hypothesis, multiple regression was employed. The result indicated that "usefulness" and "trust" affected statically to both (a) the use and (b) the future-intention use of Edunet. "Fitness of instruction" and "ease of use" affected to (c) the usefulness of Edunet. (d) The ease of use of Edunet was affected by "self-efficiency", "contents quality" and "the system-performance" of Edunet.

• Journal of Korea Spatial Information System Society
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• v.11 no.1
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• pp.169-176
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• 2009

Korean Land Spatialization Program(KLSP) is the R&D program of the National GIS Project for developing ubiquitous GIS core technologies under control of Ministry of Land, Transport and Maritime Affairs(MLTM). The first program of KLSP, from 2006 to 2012, initiated with $132 million (US dollars) of national fund and $42 million of matching fund. KLPS which aims 'Innovation of the GIS technology for the ubiquitous Korean land' consists of 5 core research projects and 1 research coordination project to practically utilize and commercialize the results of core research. Korean Land Spatialization Group(KLSG) is planning the KLSP proving ground for testing, integrating, exhibiting the KLSP's outcomes. In the near future, this proving ground would be utilized as a national ubiquitous GIS proving ground. The key objective of this paper is to present the conceptual designs and basic plans. In addition, this paper discusses characteristics of the outcomes which are applied to KLSP proving ground.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.20-25
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• 2012

As a kind of distributed energy system, the co-generation system based Diesel engine using after-treatment device was devised for its environmental friendly and economic qualities. It is utilized in that the electric power is produced by the generator connected to the Diesel engine, and waste heat is recovered from both the exhaust gases and the engine itself by the finned tube and shell & tube heat exchangers. An after-treatment device composed ceramic heater and DOC(Diesel Oxidation Catalyst) is installed at the engine outlet in order to completely reignite the unburned fuel from the Diesel engine. In this study, mutual relation of each experimental condition was derived through minimum number of experiment using Taguchi Design and ANOVA recently used in the various fields. It is found that the total efficiency (thermal efficiency plus electric power generation efficiency) of this system reaches maximum 94.4% which is approximately higher than that of the typical diesel engine exhaust heat recovery system.

• Journal of Korean Biological Nursing Science
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• v.16 no.3
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• pp.192-200
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• 2014

Purpose: The aim of this study was to develop a new course entitled 'Clinical Research Management' to enhance nursing students' clinical competency in handling clinical trials. Methods: The goals and content of the existing current education program for clinical research professionals such as clinical research coordinators and clinical research associates provided by the Korea National Enterprise for Clinical Trials were analyzed to identify the core educational concepts. A focus group interview was performed to investigate essential competency levels for the professionals who were to begin their career in the area of clinical trials after graduating from the college of nursing. Through these initial processes, we identified the core competency required for clinical research professionals and the related course content. Goals and objectives based on the specified four competencies were set and confirmed by expertise review. Results: We developed a new course entitled Clinical Research Management, a 16-week elective subject consisting of various teaching and learning strategies based on four core competencies: basic knowledge on clinical trials, communication, risk management, and ethics. Conclusion: The results of this study will contribute to enhancing nursing students' clinical competency, including knowledge, skills, and attitudes relevant to clinical trials.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.4
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• pp.61-68
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• 2015

Reactive sprays of two propellant combinations(GOx/kerosene and $GN_2O$/ethanol) were observed and compared with each other as a basic research of visualizing supercritical combustion. A shadowgraph imaging method was used to visualize the reactive sprays, and shadowgraph images were converted to density gradient magnitude images to analyse the structure of reactive sprays. The gas-liquid interface of GOx/kerosene spray showed rougher boundary and steeper density gradient near the injector face than the $N_2O$/ethanol at similar combustion chamber pressure. Spray core length was calculated from averaged density gradient magnitude images and it was revealed that spray core length of GOx/kerosene was shorter than that of $GN_2O$/ethanol, although momentum flux ratio of GOx/kerosene propellant combination was lower.

• Computers and Concrete
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• v.18 no.3
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• pp.297-317
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• 2016

Current codes recommend large amounts of shear reinforcement for reinforced concrete beam-column joints that causes significant bar congestion. Increase in congestion of shear reinforcement in joint core (connection zone), leads to increase accomplishment problems. The congestion may also lead to diameter limitations on the beam bars relative to the joint dimensions. Using double headed studs instead of conventional closed hoops in reinforced concrete beam-column joints reduces congestion and ensures easier assembly of the reinforcing cage. The purpose of this research is evaluating the efficiency of the proposed reinforcement. In this way, 10 groups of exterior beam-column joints are modeled. Each group includes 7 specimens by different reinforcing details in their joint core. All specimens are modeled by using of ABAQUS and analyzed subjected to cyclic loading. After verification of analytical modeling with an experimental specimen, 3D nonlinear specimens are modeled and analyzed. Then, the effect of amount and arrangement of headed studs on ductility, performance, ultimate strength and energy absorption has been studied. Based on the results, all joints reinforced with double headed studs represent better performance compared with the joints without shear transverse reinforcement in joints core. The behavior of the former is close to joints reinforced with closed hoops and cross ties according to the seismic design codes. By adjusting the arrangement of double-headed studs, the decrease in ductility, performance, ultimate moment resistant and energy absorption reduce to 2.61%, 0.90%, 0.90% and 1.66% respectively compared with the joints reinforced by closed hoops on the average. Since the use of headed studs reduces accomplishment problems, these amounts are negligible. Therefore, use of double-headed studs has proved to be a viable option for reinforcing exterior beam-column joints.

• Polymer(Korea)
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• v.33 no.5
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• pp.485-489
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• 2009

The temperature dependence of the structure of micelles formed by a deuterated polystyrene-poly(ethylene oxide) diblock copolymer (dPS-PEO) in heavy water were investigated with small-angle neutron scattering (SANS). SANS data were analyzed using the hard-sphere structure factor in combination with the form factor of a core-shell model. The micelle aggregation number and corona radius were obtained from the fits to the SANS data. The micelle aggregation numbers varied with temperature from 229 at $25^{\circ}C$ to 240 at $45^{\circ}C$, with a corresponding increase in the core radius. However, the shell thickness of micelles decreased with increasing temperature from 6.2 to 5.8 nm. These structural changes of micelles might be ascribed to the decrease in the hydration volume per hydrophilic group in the corona because of the increase in hydrophobicity of the PEO block with increasing temperature.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.252-257
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• 2011

The ring formation and electronic properties of furan adsorbed on graphene layers grown on 6H-SiC (0001) has been investigated using atomic force microscopy (AFM), near edge X-ray absorption fine structure (NEXAFS) spectra for the C K-edge, and core level photoemission spectroscopy (CLPES). Moreover, we observed that furan molecules adsorbed on graphene could be used for chemical functionalization via the lone pair electrons of the oxygen group, allowing chemical doping. We also found that furan spontaneously form rings with one of three different bonding configurations and the electronic properties of the ring formed by furan on graphene can be described using by AFM, NEXAFS and CLPES, respectively.

• Human Ecology Research
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• v.54 no.2
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• pp.207-225
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• 2016

This study investigated a conceptual framework of fashion consumers' purchase decision-making styles related to behavioral typology of personality. In response to critiques on fragmented and varied use of personality measurements, this study selectively tested and verified an alternative typological model of Enneagram value systems and self-construal levels that could explain the fashion consumers' typological propensities in purchase decision-making. One hundred-item measurement scale for the fashion consumers' purchase decision-making styles was developed based on the extensive literature. Three groups of fashion major students, a total of 107 participants, who respectively participated in 2-hour-long Enneagrams seminars from spring 2013 to fall 2014, were asked to re-sentence the question items to clearly reflect their Enneagram personality to make purchase decisions. Participants described their propensities in their own words about the most comfortable state during the 5-step processes of the purchase decision making process. The revised scale was distributed to 423 participants in January 2016, and the results verified the group differences in various styles in the process of purchase decision-making corresponding to the typological variables discussed in Enneagram. The correlation between Enneagram core values embodied by fashion consumers during the stages of purchase decision-making in extensive levels of self-construal were verified in the context of their fashion decision making. This study found the possibility of the typological approach toward Enneagram types of personality to be applicable to explain and predict peculiar facets of fashion consumers' purchase decision-making styles.