• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.69-80
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• 1993

Environmental hazards of a chemical could be assessed by two different approaches : toxicity test and assessment of exposure potentials to human and environmental organisms. For the prediction of environmental fate of chemicals three available computer programs were compared each other and were verified. The results obtained by using these computer programs, PCHEM, EXAMS, and E4CHEM were summarized as follows. The estimated octanol/water partition coefficients by PCHEM were similar to the experimental values in the literature. But the other factors, water solubility and vapor pressure were different from the data in the literature. The simulation results of selected compounds by EXAMS showed similar tendency to the literature results of model field environment. Therefore, this computer program could be utilized to predict the environmental fate of chemicals. E4CHEM program is very simple and this program could predict the ultimate environmental fate of stable chemicals by input of two or three parameters. However, the validity should further be verified in the future field study using more compounds. It is suggested that these approaches could be fully utilized by understanding their limitations to predict the environmental fate of new chemicals under development, to screen the potential environmental pollutants among chemicals already-in use, and to devise measures to minimize the hazards to the environment.

• Proceedings of the Korean Association for Survey Research Conference
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• 2007.11a
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• pp.55-65
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• 2007

In this research, it will be examined on mathematical model of AMOS software program that ues for Covariance Structure Analysis. if we have not understood to mathematical model of Covariance Structure, we fail to understand Structural equation modeling. Similarly If We were not understand to mathematical model of AMOS Software, we do not use Software adequately. Therefore we examine two sorts of Software that be designed for Structural equation modeling or Covariance Structure Analysis. In this research, We will focus on 8 assumption of Structural equation modeling and compare AMOS(Analysis of MOment Structure) program with LISREL(Linear Structure RELation) program. We found that A Program of AMOS Software have materialized with RAM(Reticular Action Model).

• Journal of The Korean Association of Information Education
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• v.15 no.2
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• pp.277-285
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• 2011

This research examines the effect of robots for improving creativity in elementary art classes. A creative art program with robot was developed based on research of robots and their effects on creativity, and an elementary art curriculum analysis. The program ran for 16 class periods. In this research, fifty seven 4th grade students participated, and an analysis of covariance was carried out based on before and after creativity tests. The research result shows that students who used the robot program achieved a significant improvement in their creativity over students who did not use the robot program in art classes. It proves that robots can be effective tools for improving creativity in elementary art classes.

• Toxicological Research
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• v.33 no.3
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• pp.183-189
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• 2017

AAALAC International is a private, nonprofit organization that promotes humane treatment of animals in science through a voluntary international accreditation program. AAALAC International accreditation is recognized around the world as a symbol of high quality animal care and use for research, teaching and testing, as well as promoting animal welfare. Animals owned by the institution that are used for research, teaching and testing are included as part of an accredited program. More than 990 animal care and use institutions in 42 countries around the world (more than 170 programs in 13 countries in the Pacific Rim region) have earned AAALAC International accreditation. The AAALAC International Council on Accreditation evaluates overall performance and all aspects of an animal care and use program, involving an in-depth, multilayered, confidential peer-review process. The evaluators (site visitors) consider compliance with applicable local animal legislation of the host country, institutional policies, and employ a customized approach for evaluating overall program performance using a series of primary standards that include the Guide for the Care and Use of Laboratory Animals, the Guide for the Care and Use of Agricultural Animals in Research and Teaching, or the European Convention for the Protection of Vertebrate Animals Used for Experimental and Other Purposes, Council of Europe (ETS 123), and supplemental Reference Resources, as applicable.

• Carbon letters
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• v.11 no.4
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• pp.336-342
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• 2010

Different oxidation treatments on CNTs using diluted 4.0 M $H_2SO_4$ solution at room temperature and or at $90^{\circ}C$ reflux conditions were investigated to elucidate the physical and chemical changes occurring on the treated CNTs, which might have significant effects on their performance as catalyst supports in PEM fuel cells. Raman spectroscopy, X-ray diffraction and transmission electron microscope analyses were made for the acid treated CNTs to determine the particle size and distribution of the CNT-supported Pt-Ru nanoparticles. These CNT-supported Pt-based nanoparticles were then employed as anode catalysts in PEMFC to investigate their catalytic activity and single-cell performance towards $H_2$ oxidation. Based on PEMFC performance results, refluxed Pt-Ru/CNT catalysts prepared using CNTs treated at $90^{\circ}C$ for 0.5 h as anode have shown better catalytic activity and PEMFC polarization performance than those of the commercially available Pt-Ru/C catalyst from ETEK and other Pt-Ru/CNT catalysts developed using raw CNT, thus demonstrating the importance of acid treatment in improving and optimizing the surface properties of catalyst support.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.825-832
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• 2008

A simulation program is developed for analysing thermal networking process between the District heating and the CES(Community Energy Supply) systems. The effects of thermal networking on the District heating facilities previously being operated are implemented using mathematical correlations in terms of the fuel consumption and energy load such as heating and electricity. The operational characteristics according to the prime movers is modeled based on the materials of efficiency as a function of operational load. The unit energy load model is also developed extensively for several building types such as apartment complex, hotel, hospital, buildings for business and commercial use respectively. The specific features of the newly developed program in simulation of thermal networking process in district heating is described in terms of the reliability and the easiness for operating it etc.

• Journal of Adhesion and Interface
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• v.12 no.2
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• pp.67-72
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• 2011

Acrylic pressure-sensitive adhesives are used in many different parts in the world. But acrylic acid in PSAs may occur unexpected results such as corroding adherends or producing by-products when applied within electronic devices. This study employed acrylic PSAs based on 2-ethylhexyl acrylate (2-EHA), 2-hydroxyethyl acrylate (2-HEA) and butyl acrylate (BA) with different coating thickness. There are two types of curing agents. One is methylaziridine derivative (MAZ) and the other is aluminum acetylacetonate (AlACA). This study examined the adhesion performance and curing behaviors using peel strength, probe tack and gel fraction. Also, the viscoelastic properties of acrylic PSAs were investigated from Advanced rheometric expansion system (ARES).

• Journal of the Korean Wood Science and Technology
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• v.41 no.2
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• pp.134-140
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• 2013

UV curing was introduced via a chemical treatment by adding small amounts of a hexafunctional acrylic monomer and a photoinitiator to improve the mechanical properties of PLA. This study also employed a semi-interpenetrated structured polymer network through the process of UV-curing. The UV curing behaviors were investigated using FTIR-ATR spectroscopy and gel fraction determination. Also, the tensile strength was investigated with different hexafunctional acrylic monomer contents and UV doses. The results showed that the crosslinking of UV-induced chemically treated PLA started at a low content of hexafunctional acrylic monomer, resulting in a significant improvement of the mechanical properties compared to those of neat PLA due to crosslinking.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.307-310
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• 2008

In the framework of COMS(Communication, Ocean and Meteorological Satellite) programme, the first bipropellant propulsion system for GEO satellite has been developed successfully. So far Korea has its own experience of development of a monopropellant propulsion system for LEO satellites, i.e., KOMPSAT's. Other types of propulsion systems for a satellite, such as cold gas and electric propulsion etc., are being developed somewhere in Korea, however they are not commercialised yet, apart from those two systems aforementioned. This paper mainly focused on the design of the Chemical Propulsion System(CPS) for the COMS, joint scientific and communications satellite. It includes descriptions of the general system design and a summary of the supporting analysis performed to verify suitability for space flight. Essentially it provides an overview and guide to the various engineering rationale generated in support of the COMS CPS design activities. The manufacture and subsequent testing of COMS CPS are briefly discussed. Feasibility of COMS CPS to an interplanetary mission is proposed as well.

• Journal of Distribution Science
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• v.20 no.12
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• pp.99-108
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• 2022

Purpose: This study attempted to identify determinants affecting research collaboration and R&D distribution activities, especially regarding facility and equipment leasing of small and medium enterprises (SMEs) in South Korea. The objective of this study was to find the most significant firm characteristics that affect firms participating in an R&D collaboration and distribution program and investing in R&D in terms of leasing payment for equipment. Research design, data, and methodology: This study analyzes which SMEs' characteristics influence external research cooperation activities by examining the SMEs that received government support for equipment leasing using multiple regression analysis and residual plots. The survey combined two databases: 1) a fact-finding survey of participating firms by the Ministry of SMEs and Startups, and 2) leasing information by the Korea Association of University, Research Institute and Industry. Results: The study found that firm size positively impacts R&D investment, R&D collaboration and distribution. Conclusions: The study provided evidence to policymakers and government officials that firms with more employees will more likely participate in government support programs. The study results also prove that government officials believe firm location does not impact R&D investment, R&D collaboration and distribution.