• Applied Biological Chemistry
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• 제40권4호
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• pp.289-293
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• 1997

쌀전분겔의 노화에 첨가물이 미치는 영향을 알아보기 위하여 동진 쌀전분에 슈크로오스 지방산 에스테르, 이소말토올리고당과 명반을 전분량에 대하여 0.1, 0.3, 0.5% 첨가하여 제조한 40% 전분겔을 $20{\pm}1^{\circ}C$에서 저장하면서 노화특성을 비교하였다. 슈크로오스 지방산 에스테르를 첨가한 것은 저장 3일까지 모두 노화 억제 효과가 있었으며, 첨가수준이 증가하면 노화억제 효과도 증가하였다. 올리고당을 0.1% 첨가한 것은 저장 3일간 노화 억제 효과를 보였지만 0.3%, 0.5% 첨가한 경우에는 저장 초기에는 억제 효과가 컸으나 저장 3일이 되면 노화가 촉진되었다. 명반을 첨가한 경우에도 0.1% 첨가한 것은 노화억제 효과가 있었으나 0.3%는 저장 1일, 0.5%는 저장 12시간 이후에는 노화가 급속히 진행되었다. 첨가물에 따른 노화 억제 효과는 첨가 수준에 따라 다른 경향을 보여 0.1%일 때는 거의 비슷한 노화억제 효과를 보였으나 0.5% 첨가시, 저장 2일까지는 올리고당

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.71.2-71.2
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• 2010

CIS(CuInSe2)계 화합물 태양전지는 높은 광흡수계수와 열적 안정성으로 고효율의 태양전지 제조가 가능하여 화합물 태양전지용 광흡수층으로서 매우 이상적이다. 또한 In 일부를 Ga으로 치환하여 밴드갭을 조절할 수 있는 장점이 있다. 미국 NREL에서는 Co-evaporation 방법을 이용해 20%의 에너지 변환 효율을 달성하였다고 보고된바가 있다. 본 연구에서는 미국의 NREL과 같은 3 stage 방식을 이용하여 광흡수층을 제조하고자 한다. 본 실험에서는 Se 증기압을 각각 $200^{\circ}C$, $230^{\circ}C$, $240^{\circ}C$, $245^{\circ}C$로 달리 하며 실험을 실시하였다. 이때 1st stage의 시간은 15분으로 고정하였으며 기판온도는 약 $250^{\circ}C$로 고정 하였다. 2nd stage는 실시간 온도 감지 장치를 이용하여 Cu와 In+Ga의 조성비가 1:1이 되는 시간을 기준으로 Cu의 조성을 30%더 높게 조절하였으며 기판 온도는 약 $520^{\circ}C$로 고정 후 실험을 실시하였다. 3rd stage의 경우 Cu poor 조성으로 조절하기 위해 모든 조건을 10분으로 고정 후 실험을 실시하였다. 각각의 Se 증기압에 따른 물리적, 전기적 특성을 알아보기 위해 FE-SEM, EDS, XRD 분석을 실시하였다. 본 연구에서 기판은 Na이 첨가되어있는 soda-lime glass를 사용 하였으며 후면 전극으로 약60nm 두께의 Mo를 DC Sputtering 방법을 이용해 증착 하였다.

• 대한전기학회논문지
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• 제43권2호
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• pp.296-302
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• 1994

Polycrystalline CuInSeS12T thin were prepared by depositing Cu/In layer, which was sequentially sputtered varying the Cu/(Cu+In) mole ratio, on glass substrate and selenizing with selenium metal vapor in a nitrogen atmosphere. Compositional and structural, characterization was carried out by X-ray diffraction (XRD), wavelength-dispersive spectroscopy(WDS), and scanning electron microscope(SEM). Electrical characterization was carried out by the measurements of Hall effect, electrical resistivity. Large indium loss occurs in early stage of the selenization process. The selenized films which had mole ratios larger than 0.28 have chalcopyrite CuInSeS12T phase and these that had less mole ratios have sphalerite phase. The selenized films containing CuS1xTSe phase have Cu-rich CuInSeS12T phase and these that did not contain CuS1xTSe have In-rich CuInSeS12T phase. By optimizing the sputtering conditions,it is possible to fabricate CuInSeS12T thin films which have little secondary phases and an appropriate hole concentration (10S015T ~ 10S016TcmS0-3T) for solar cells.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술대회 논문집 전문대학교육위원
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• pp.124-126
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• 2003

The results of investigations of $Ag_2Se$ single crystal is presented. $Ag_2Se$ crystal was grown by the Bridgman method. The $Ag_2Se$ single crystal was an orthorhombic structure with lattice constance a=4.1686 $\AA$, b=9.0425 $\AA$, c=8.0065 $\AA$. Hall effect shows a n-type conductivity in the $Ag_2Se$ single crystal. The electrical resistivity values was $1.25{\times}10^3ohm^{-1}cm^{-1}$ and electron mobility was $-5.48{\times}10^3cm^2/V{\cdot}sec$ at room temperature(RT).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.302-302
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• 2011

The binary chalcogenide semiconductor Bi2Se3 is at the center of intensive research on a new state of matter known as topological insulators. It has Dirac point in their band structures with robust surface states that are protected against external perturbations by strong spin-orbit coupling with broken inversion symmetry. Such unique band configurations were confirmed by recent angle-resolved photoelectron emission spectroscopy experiments with an unwanted n-type doping effect, showing a Fermi level shift of about 0.3 eV caused by atomic defects such as Se vacancies. Since the number of defects can be reduced using the molecular beam epitaxy (MBE) method. We have prepared the Bi2Se3 film on noble metal Au(111) and semiconductor Si(111) substrates by MBE method. To characterize the film, we have introduced several surface sensitive techniques including x-ray photoemission electron spectroscopy (XPS) and micro Raman spectroscopy. Also, crystallinity of the film has been confirmed by x-ray diffraction (XRD). Using home-built scanning tunneling microscope, we observed the atomic structure of quintuple layered Bi2Se3 film on Au(111).

• 통합자연과학논문집
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• 제3권1호
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• pp.54-59
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• 2010

A stoichiometric mixture of evaporating materials for $ZnIn_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $ZnIn_2Se_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $ZnIn_2Se_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.41{\times}10^{16}cm^{-3}$ and $292cm^2/v{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $ZnIn_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $Eg(T)=1.8622eV-(5.23{\times}10^{-4}eV/K)T^2/(T+775.5K)$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.354-355
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• 2007

Process variables for manufacturing the $CuInSe_2$ thin film were established in order to clarify optimum conditions for growth of the thin film depending upon process conditions (substrate temperature, sputtering pressure, DC/RF Power), and then by changing a number of vapor deposition conditions and Annealing conditions variously, structural and electrical characteristics were measured. Thereby, optimum process variables were derived. For the manufacture of the $CuInSe_2$, Cu, In and Se were vapor-deposited in the named order. Among them, Cu and In were vapor-deposited by using the sputtering method in consideration of their adhesive force to the substrate, and the DC/RF power was controlled so that the composition of Cu and In might be 1 : 1, while the surface temperature having an effect on the quality of the thin film was changed from 100[$^{\circ}C$] to 300[$^{\circ}C$] at intervals of 50[$^{\circ}C$].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.124-127
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• 2003

The stochiometric $AgGaSe_2$ polycrystalline mixture of evaporating materials for the $AgGaSe_2$ single crystal thin film was prepared from horizontal furnance. To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal and semi-insulating GaAs(100) wafer were used as source material and substrate for the Hot Wall Epitaxy (HWE) system, respectively. The source and substrate temperature were fixed at $630^{\circ}C$ and $420^{\circ}C$, respectively. The thickness of grown single crystal thin films is $2.1{\mu}m$. The single crystal thin films were investigated by photoluminescence and double crystal X-ray diffraction(DCXD) measurement. From the photoluminescence measurement of $AgGaSe_2$ single crystal thin film, we observed free excition ($E_x$) observable only in high quality crystal and neutral bound excition ($D^{\circ}$,X) having very strong peak intensity. And, the full width at half maximum and binding energy of neutral donor bound excition were 8 meV and 14.1 meV, respectively. By Haynes rule, an activation energy of impurity was 141 meV.

• The Journal of Korean Physical Therapy
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• 제34권4호
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• pp.155-160
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• 2022

Purpose: This study was to identify the effect of cervical stabilization exercise with visual feedback on the craniovertebral angle and foot pressure in subjects with forward head posture. Methods: Thirty healthy adults were recruited in the study. Participants were randomly assigned to the stabilization exercise with visual feedback (SE-VF) group (n=15) or stabilization exercise (SE) group (n=15). The SE-VF group performed cervical stabilization exercise while sitting on a chair without a backrest and checking their side profile in real time a monitor 3m away. The SE group performed the same cervical stabilization exercise as the SE-VF group accompanied by without visual feedback. Craniovertebral angle (CVA) was measured to quantify forward head posture, and the foot pressure of the subjects were evaluated. Results: The foot pressure showed statistically significant differences pre and post in both midfoot and left metatarsal only in SE-VF group (p<0.05). Conclusion: These findings of this study showed that the cervical stabilization exercise with visual feedback was effective for the foot pressure of subjects. In addition, based on the results of this study, it is suggested that visual feedback will be effective in cervical stabilization exercise.

• 디지털융복합연구
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• 제14권8호
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• pp.93-104
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• 2016

본 연구의 목적은 제3문화 청소년의 가족건강성과 민족정체성의 관계에서 자아존중감의 매개효과를 검증해 보는 것이었다. 이를 위해 미국의 동부 버지니아 페어팩스(Fairfax) 카운티 지역과 서부 캘리포니아 얼바인(Irvine) 두 지역을 중심으로 한국인 청소년 혹은 미국시민권을 지니고 있지만 모국이 한국인인 청소년 86명을 대상으로 자료를 수집하여 분석하였다. 자료 분석은 SPSS 18.0 프로그램을 이용하여 기술통계, t-test와 일원분석분석, 상관분석, 회귀 분석을 실시하였고, 매개효과의 유의성을 검증하기 위해 Sobel test를 실시하였다. 본 연구의 주요결과는 첫째, 가족건강성, 자아존중감 그리고 민족정체성은 정적상관을 지니는 것으로 나타났다. 둘째, 가족건강성과 민족정체성의 관계에서 자아존중감은 부분매개효과를 지니는 것으로 나타났다. 셋째, 민족정체성 하위변인 중 민족정체성 탐색의 경우 가족건 강성과의 관계에서 자아존중감이 부분매개효과를 지니는 것으로 나타났으며, 민족소속감의 경우 자아존중감은 유의미한 영향력을 미치는 반면 가족건강성은 유의미한 영향력이 없는 것으로 나타났다. 이러한 연구결과를 바탕으로 건강한 민족정체성 형성을 위한 연구의 함의와 시사점 및 연구의 한계 그리고 후속연구를 위한 제언을 제시하였다.