• Journal of the Korean Society of Systems Engineering
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• v.15 no.2
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• pp.87-97
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• 2019

This paper focuses on the SE concept based on the weapon system design, which is the lack of systematic research at the stage of military requirements creation prior to acquisition management phase. Influence factors were derived by focusing on the core issues that were at issue in the process of requirements analysis, requirements verification, and business management in recent years. Next, the impact factor was prioritized using the AHP technique and then alternatives were suggested. As a result, through the hierarchical analysis process, 'substantiation of necessity' was found to be the most important factor in the large category, and 'satisfaction of the operating concept' was the most important factor. In addition, as a result of calculating the final weight for each nutritional factor, it was analyzed in order of 'enemy threat response ability', 'response to operational environment change', 'performance considering operational environment', and 'guaranteed power generation'. The results of this analysis suggest which factors should be focused on, firstly, based on the concept of SE by the military and JCS.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.01a
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• pp.213-214
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• 2019

본 논문에서는 초등 현직 교사 146명을 대상으로 실시한 소프트웨어 교육 교수효능감 검사지(Software Education Teaching Efficacy Belief Instrument, SE-TEBI) 조사 결과에 따라 교사의 성별, 지역, 경력, 연수 경험 및 시간, SW 교육에 대한 태도와의 상관을 알아보기 위하여 이변량 상관관계 분석을 실시하였다. 그 결과, 소프트웨어 교육 교수효능감(Software Education Teaching Efficacy, SE-TE)에 가장 높은 관련성을 보이는 것은 SW 교육에 대한 태도였으며, 그 다음의 관련성을 보이는 것은 연수 경험 및 시간이었다. 성별은 부적 상관을 보였으며, 지역과 경력은 통계적으로 유의한 상관을 보이지 않았다. 이러한 분석결과는 초등 교사의 SE-TE를 증진시키기 위해서는 SW교육에 대한 긍정적인 태도를 함양할 수 있도록 지속적인 연수 경험을 제공하여야 함을 시사한다.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.5
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• pp.730-746
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• 2015

Selenium plays an important role in boar nutrition via participating in selenoprotein synthesis. It seems likely that selenoproteins are central for antioxidant system regulation in the body. Se-dependent enzyme glutathione peroxidase (GSH-Px) is the most studied selenoprotein in swine production. However, roles of other selenoproteins in boar semen production and maintenance of semen quality also need to be studied. Boar semen is characterised by a high proportion of easily oxidized long chain polyunsaturated fatty acids and requires an effective antioxidant defense. The requirement of swine for selenium varies depending on many environmental and other conditions and, in general, is considered to be 0.15 to 0.30 mg/kg feed. It seems likely that reproducing sows and boars are especially sensitive to Se deficiency, and meeting their requirements is an important challenge for pig nutritionists. In fact, in many countries there are legal limits as to how much Se may be included into the diet and this restricts flexibility in terms of addressing the Se needs of the developing and reproducing swine. The analysis of data of various boar trials with different Se sources indicates that in some cases when background Se levels were low, there were advantages of Se dietary supplementation. It is necessary to take into account that only an optimal Se status of animals is associated with the best antioxidant protection and could have positive effects on boar semen production and its quality. However, in many cases, background Se levels were not determined and therefore, it is difficult to judge if the basic diets were deficient in Se. It can also be suggested that, because of higher efficacy of assimilation from the diet, and possibilities of building Se reserves in the body, organic selenium in the form of selenomethionine (SeMet) provided by a range of products, including Se-Yeast and SeMet preparations is an important source of Se to better meet the needs of modern pig genotypes in commercial conditions of intensive pig production.

• Journal of Nutrition and Health
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• v.26 no.7
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• pp.899-906
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• 1993

Human blood selenicum(Se) level depends on the Se content and bioavailablilty of foods. In countries where the soil has low Se content, the differences of Se intake and blood Se concentration are shown according to the type of diet. In this study, Se status of women eating an average German diet(175 German healthy women) and wholesome nutrition group(243 women) were studied. There were significant differences in wholeblood and plasma Se levels between the two groups. In average German diet group, mean wholeblood Se concentration was 84.97ug/l and plasma Se concentration was 75.02ug/l. In wholesome nutrition group mean wholeblood Se concentration and plasma Se concentration with Se levels, correlation analysis was conducted between Se concentration and BMI, age and daily food intake. BMI and age did not correlate significantly with wholeblood and plasma Se levels. In wholesome nutrition group, serum and wholeblood Se levels had significant correlation with fish intake.

• Journal of Electrochemical Science and Technology
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• v.10 no.3
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• pp.313-320
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• 2019

In this study, cobalt diselenide ($CoSe_2$) and the composites ($CoSe_2@RGO$) of $CoSe_2$ and reduced graphene oxide (RGO) were synthesized by a facile hydrothermal reaction using cobalt ions and selenide source with or without graphene oxide (GO). The formation of $CoSe_2@RGO$ composites was identified by analysis with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and scanning electron microscopy (SEM). Electrochemical analyses demonstrated that the $CoSe_2@RGO$ composites have excellent catalytic activity for the reduction of $I_3{^-}$, possibly indicating a synergetic effect of $CoSe_2$ and RGO. As a consequence, the $CoSe_2@RGO$ composites were applied as a counter electrode in DSSC for the reduction of redox couple electrolyte, and exhibiting the comparable power conversion efficiency (7.01%) to the rare metal platinum (Pt) based photovoltaic device (6.77%).

• Journal of Powder Materials
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• v.29 no.5
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• pp.370-375
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• 2022

Cu-doped ZnSe quantum dots were successfully synthesized in an aqueous solution using an internal doping method. The effects of ligand type, CuSe synthesis temperature, and heating time on Cu-doped ZnSe synthesis were systematically investigated. Of MPA, GSH, TGA, and NAC used as ligands, MPA was the optimal ligand as determined by PL spectrum analysis. In addition, the emission wavelength was found to depend on the synthesis temperature of the internal doping core of CuSe. As the temperature increased, the doping of Cu²⁺ was enhanced, and the emission wavelength band was redshifted; accordingly, the emission peaks moved from blue to green (up to 550 nm). Thus, the synthesis of Cu:ZnSe using internal doping in aqueous solutions is a potential method for ecomanufacturing of color-tuned ZnSe quantum dots for display applications.

• Korean Journal of Materials Research
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• v.31 no.12
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• pp.657-664
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• 2021

To build a highly active photocatalytic system with high efficiency and low cast of TiO₂, we report a facile hydrothermal technique to synthesize Ag₂Se-nanoparticle-modified TiO₂ composites. The physical characteristics of these samples are analyzed by X-ray diffraction, scanning electron microscopy with energy dispersive X-ray analysis, transmission electron microscopy and BET analysis. The XRD and TEM results show us that TiO₂ is coupled with small sized Ag₂Se nanoplate, which has an average grain size of about 30 nm in diameter. The agglomeration of Ag₂Se nanoparticles is improved by the hydrothermal process, with dispersion improvement of the Ag₂Se@TiO₂ nanocomposite. Texbrite BA-L is selected as a simulated dye to study the photodegradation behavior of as-prepared samples under visible light radiation. A significant enhancement of about two times the photodegradation rate is observed for the Ag₂Se@TiO₂ nanocomposite compared with the control sample P25 and as-prepared TiO₂. Long-term stability of Ag₂Se@TiO₂ is observed via ten iterations of recycling experiments under visible light irradiation.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.127-127
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• 2002

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.1
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• pp.60-66
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• 2009

A new analytical method is presented for the shielding effectiveness(SE) of an enclosure with a dielectric-backed aperture. The previously proposed methods cannot consider the effect of the dielectric on the aperture. The comparisons among our method, previous method, and commercial programs give good correspondence. The method is used to calculate SE with varying permittivity and thickness of dielectric sheet, probe position, width and height of aperture.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.3
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• pp.377-385
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• 1996

ZnS/ZnSe superlattices were prepared on GaAs (100) substrates by hot wall epitaxy, an the structures were analyzed using x-ray diffraction. It is shown that the x-ray diffraction of the strained superlattice gives very useful information about the thickness of each layer, strain, interdiffusion, and the fluctuation of the superlattice period. Interdiffusion length of the S and Se is estimated to be less than $2\;{\AA}$.