• 시스템엔지니어링학술지
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• 제8권2호
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• pp.1-10
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• 2012

This paper aims to analyze the result of SE Process Implementation on Light Rail Transit(LRT) Project. Currently the Light Rail Transit Project of Korea applies SE to the intermediate phase, that is, E&M phase which is a manufacturing and designing procedure. More seriously, the application effect of SE is not remarkable because it applies to some specific engineering fields like RAMS and it depends on superficial consulting of foreign companies with low SE support capability and investment capital. This study points out that the "Requirement Analysis" and "System Alternative Review" has not been conducted from the initial phase (basic plan and basic design) of the LRT projects. Several projects indicate that the amount of investments for SE activities through the Korea LRT project is relatively very small in comparison with the global capital which is about 10% of total project budget. Furthermore, Korea LRT projects have very few SE professionals and weak SE organization with no government directions and guide book for the efficient implementation of SE for the LRT projects.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.383-386
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• 2002

Polycrystalline Cu(In,Ga)Se$_2$(CIGS) thin-films were grown by co-evaporation on a soda lime glass substrate. In this paper the effects of the Se evaporation temperature on the properties of CuIn0.75Ga0.25Se2 (CIGS) thin films. Structure, surface morphology and optical properties of CIGS thin films deposited at various Se evaporation temperatures have been investigated using a number of analysis techniques. X-ray diffraction (XRD) analysis shows that CIGS films exhibit a strong <112> preferred orientation. As expected, at higher Se evaporation temperatures the films displayed a lower degree of crystallinity. The <112> peak was also enhanced and other CIGS peaks appeared simultaneously. These results were supported by experimental work using scanning electron microscopy When the Se evaporation temperature was increased, the average grain size also decreased together with a reduction Cu content. The Se evaporation temperature also had a significant inf1uence on the transmission spectra. Increasing the Se evaporation temperature, the cell efficiency was improved dramatically to 11.75% with Voc = 556 mV, Jsc = 32.17 mA/cm2 and FF = 0.66. The Se evaporation temperature is an important parameter in thin film deposition regardless of the deposition technique being used to deposit thin films

• 한국응용곤충학회지
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• 제61권3호
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• pp.449-460
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• 2022

광식성 난방제 해충인 파밤나방(Spodoptera exigua)의 친환경적 방제원으로써 이용을 위해 국내에서 분리된 파밤나방 핵다각체병바이러스(S. exigua nucleopolyhedrovirus K1: SeNPV-K1)의 형태 및 전체 유전체 서열을 분석하였다. SeNPV-K1의 다각체(polyhedra)는 0.6-1.8 um 크기의 부정형으로, 기 보고된 SeNPV와 외형적 차이는 보이지 않았다. 전체 유전체의 염기서열을 분석한 결과, 기 보고된 SeNPV와 비교할 때 145 bp 더 많은 135,756 bp로 확인되었으며, G+C 함량은 44% 였고 상동반복영역은 6개로 두 바이러스간에 차이는 없었다. ORF 분석결과, SeNPV-K1은 기 보고된 것과 비교할 때 2개 더 적은 137개를 가지며, SeNPV-K1에만 존재하는 ORF는 4개가 확인되었다. 이들 4개의 ORF는 비필수 유전자로 바이러스의 특성에는 큰 영향을 주지 않을 것으로 여겨졌다. 유전체의 vista 분석 결과, SeNPV-K1과 기 보고된 SeNPV의 전체 염기서열 유사도가 매우 높은 것으로 확인되었다. 국내에서 처음으로 분석한 SeNPV-K1의 전체 유전체는 기 보고된 SeNPV와 유사한 것으로 나타났으나 서로 다른 분리주로 국내 고유자원임을 확인하였다.

• 한국재료학회지
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• 제16권11호
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• pp.663-667
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• 2006

CTAB(cetyltrimethylammonium bromide)-capped CdSe nanoparticles were prepared by using a 4 : 1(v/v) distilled water-isopropyl alcohol mixture. The cadmium chloride and sodium selenosulfate were used as the cadmium and selenium source. By the analysis of XRD and XPS, the resultant particle was confirmed to be cubic CdSe phase. TEM image showed CdSe nanoparticles with empty core. The CTAB-capped sample showed an maximum absorption at 418nm, blue-shifting compared with bulk CdSe, which indicated stronger quantum confinement effect compared with uncapped sample. From FT-IR analysis, it was found that the presence of the new peaks in the $850{\sim}1250cm^{-1}$ range indicated the existence of chemical bonding between CTAB and surface of CdSe nanoparticles. Also TG analysis indicated that there were two weight-loss steps for the CTAB-capped CdSe nanoparticles. It was suggested that CTAB played a significant role in protecting CdSe nanoparticles.

• 한국식품과학회지
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• 제3권3호
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• pp.144-149
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• 1971

폐암과 담배와 밀접한 인과관계가 있음을 알게된 후, 독성원소(As, Se, Hg, Br)는 발암성 물질로서 문제화되고 있다. 특히 Se은 담배와 그 종이에도 함유되고 있음이 분석결과 나타났으며 이 무기화합물은 극히 유독하여 폐암의 원인이 되고 있지 않은가 생각된다. 그러나 이 독성원소(As, Se, Hg, Br)는 극미량이 있음으로 방사화분석으로 정량하는 것이 효과적일 줄 믿고 실험하였다. 본 실험은 한국산 및 외국제(미국산, 일본산)의 담배를 시료로 수집하여 건조한 것을 vial에 넣고 열중성자속 $3.8{\times}10^{12}n/cm\;sec$에 15시간 조사하였다. 이 시료를 Bethge 장치로 분해시켜, 수은, 비소, Br을 증류하여 TMC 100 channel pulse height analyzer로 측정 하였다. Se 분석은 $^{77m}Se\;18$초의 핵종을 이용하여 비 파괴분석하였다. 국산담배에서는 Br $5.9{\sim}8.4\;ppm$, As $0.49{\sim}0.79\;ppm,\;Hg\;0.53{\sim}0.95\;ppm,Se\;0.92{\sim}1.45\;ppm$ 함유하고 있으며, 이것을 외산담배와 Br, As, Hg, Se 함량을 비교한 결과를 발표한다.

• 국제물리치료학회지
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• 제11권3호
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• pp.2155-2163
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• 2020

Background: Various treatments have been proposed for chronic low back pain (CLBP), but recent guidelines and reviews recommend regular physical exercise. However, some other studies have reported opposite results that sling exercise (SE) and other exercises (OE) did not differ in improving CLBP. Objectives: To systematically review and meta-analyze the effects of SE on CLBP in studies published in Korea. Design: A Systemic Review and Meta-analysis. Methods: Randomized controlled trials comparing SE with OE and modality therapy (MT), published up to June 2020, were identified by electronic searches. Primary outcomes were pain and disability. The weighted mean difference (WMD), stand mean difference (SMD) and 95% confidence interval (CI) were calculated using a random-effects model. Results: Based on the results of the meta-analysis, SE was effective for pain in the comparison of SE and MT [short-term: WMD=-1.64, 95% CI (-3.06, -0.22); long-term: WMD=-0.34, 95% CI (-0.42, -0.26)]. It was effective for pain in the comparison of SE and OE [short-term: WMD=-1.18, 95% CI (-2.15, -0.20); long-term: WMD=-0.66, 95% CI (-0.89, -0.43)]. It was also effective for disability in the comparison of SE and MT [short-term: SMD=-15.82, 95% CI (-23.10, -8.54)]. We found no clinically relevant differences in disability between SE and OE. Heterogeneity was high in the comparison of SE and overall variables. Conclusion: If SE is applied to physical therapy to improve the main symptoms of CLBP patients, it may contribute to their recovery. More high-quality randomized studies on the topic are warranted.

• 분석과학
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• 제16권5호
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• pp.399-406
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• 2003

본 연구는 수소화물 발생장치가 부착된 원자흡광 광도계 (HG-AAS)를 이용하여 비교적 고농도의 Se을 함유하고 있는 석유정제 폐수의 Se 분석을 위하여 적합한 분석조건을 선정하고자 수행되었다. Se(VI)의 Se(IV)로의 환원 실험에서 폐수량 10 mL, 염산 주입량 10 mL, 가열시간 30분이 최적 환원조건으로 결정되었다. 폐수의 조성성분과 유기물의 농도가 높은 경우에는 Se 회수율이 감소하였다. 따라서 3가지 산분해법 ($HNO_3/HClO_4$ 분해, $KMnO_4$ 분해 및 초단파 산분해)에 의한 유기물, 석유화합물 분해 및 유기성 Se(org.), Se(IV) 산화에 따른 Se 회수율을 검토하였다. 실험결과 산분해전 약 50~80%이었던 Se 회수율은 모든 산분해에서 90%이상이었으며 특히, 초단파 산분해에 의한 Se 회수율이 가장 높은 것으로 나타났다. 그러므로 HG-AAS를 이용한 석유정제 폐수의 Se 분석시에는 초단파 산분해후 염산 처리를 하는 전처리 과정이 가장 적합한 것으로 나타났다.

• 한국세라믹학회지
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• 제52권6호
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• pp.489-496
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• 2015

In this study, novel $Ag_2Se$ sensitized $TiO_2$ nanocomposites were prepared by facile sonochemical assisted synthesis method. The as-prepared products were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and N2 adsorption BET analysis. The as-prepared $Ag_2Se/TiO_2$ nanocomposites simultaneously possessed great adsorptivity for organic dyes and efficient charge separation properties. In the decolorization of rhodamine B, a significant enhancement in the reaction rate was observed for the $Ag_2Se/TiO_2$ nanocomposite compared to the cases of using pure P25 or $TiO_2$. The sonocatalysis activity was higher due to the greater formation of reactive radicals, as well as to the increase of the active surface area of the $Ag_2Se/TiO_2$ nanocomposite.

• 한국세라믹학회지
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• 제54권3호
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• pp.205-210
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• 2017

In this study, we examined the photo-degradation efficiency of $CoSe_2$-Graphene-$TiO_2$ ($CoSe_2-G-TiO_2$) nanocomposites under visible light irradiation using rhodamine B (RhB) as standard dye. $CoSe_2-G-TiO_2$ nanocomposites were synthesized by ultrasonication and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopic analysis and UV-Vis absorbance spectra analysis. Our results show that the $CoSe_2-G-TiO_2$ nanocomposite exhibited significant photo degradation efficiency compared to pure $TiO_2$ and $CoSe_2-G$, approximately 85.2% of the rhodamine (Rh B) degraded after 2.5 h. It is concluded that the $CoSe_2-G-TiO_2$ nanocomposite is a promising candidate for use in dye pollutants.

• 분석과학
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• 제18권1호
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• pp.23-26
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• 2005

셀렌은 항산화 작용을 하는 미량 원소로 잘 알려져 있으며 많은 고객들은 다양한 식품시료중의 셀렌의 농도 및 정량에 관심을 갖고 있다. 본 연구에서는 $^{75}Se$과 $^{77m}Se$ 핵종을 이용한 중성자 방사화 분석법에 의한 생물시료중의 셀렌 분석법을 확립하고 비교하고자 하였다. 이를 위하여 미국표준연구원의 3종의 인증 표준물질을 선택하여 미리 설정된 분석조건 (조사, 냉각 및 측정시간) 하에서 셀렌의 농도를 결정하였다. 두 가지 분석방법에 의한 측정값을 인증값과 평가하였으며 $^{75}Se$과 $^{77m}Se$의 측정값에 대한 검출한계와 불확도를 서로 비교 하였다.