• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.158-161
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• 2006

Superstrate pin amorphous silicon thin-film (a-Si:H) solar cells are prepared on $SnO_2:F$ and ZnO:Al transparent conducting oxides (TCO) In order to see the effect of TCO/P-layers on a-Si:H solar cell operation. The solar cells prepared on textured ZnO:Al have higher open circuit voltage $V_{oc}$ than cells prepared on $SnO_2:F$. Presence of thin microcrystalline p-type silicon layer $({\mu}c-Si:H)$ between ZnO:Al and p a-SiC:H plays a major role by causing improvement in fill factor as well as $V_{oc}$, of a-Si:H solar cells prepared on ZnO:Al TCO. Without any treatment of pi interface, we could obtain high $V_{oc}$, of 994mv while keeping fill factor (72.7%) and short circuit current density $J_{sc}$ at the same level as for the cells on $SnO_2:F$ TCO. This high $V_{oc}$ value can be attributed to modification in the current transport in this region due to creation of a potential barrier.

• 대한방사선기술학회지:방사선기술과학
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• 제32권2호
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• pp.169-175
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• 2009

본 연구는 초음파진단장치의 3.5 MHz 프로브로 20대 정상 성인의 식전 후 쓸개용적과 쓸개벽두께를 시간별로 추적주사하고 이것들의 추이변화를 분석 평가하여 다음과 같은 결론을 얻었다. 1. 식전 평균 쓸개용적은 남자 47.40 $m\ell$(SD 9.05), 여자 35.72 $m\ell$(SD 8.30)이었다. 2. 식전 평균 쓸개벽두께는 남 여 모두 2.3 mm(SD 0.3, SD 0.5)이었다. 3. 평균 쓸개박출계수(%)는 남자 67.20%, 여자 63.95%이었다. 4. 쓸개용적은 남 여 모두 식후 4시간까지는 음상관관계(v = -.487, p < .000, v = -.509, p < .000), 4시간 이후는 순상관관계(v = .434, p < .000, v = .440, p < .000)를 보였다. 5. 쓸개벽두께는 남 여 모두 식후 3시간까지는 순상관관계(t = .310, p < .002, t = .116, p < .246), 3시간 이후는 음상관관계(t = -.288, p < .010, t = -.126, p < 7.10)를 보였다. 6. 남 여 쓸개용량과 벽두께의 시간별 추이는 역상관관계를 나타냈다.

• 한국재료학회지
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• 제19권11호
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• pp.613-618
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• 2009

We designed new compositions for lead free and low temperature sealing glass frit of $ZnO-V_2O_5-P_2O_5$ system, which can be used for PDP (Plasma Display Panel) or other electronic devices. The $ZnO-V_2O_5-P_2O_5$ system can be used as a sealing material at temperatures even lower than 430$^{\circ}C$. This system, however, showed lower bonding strength with glass substrate compared to commercialized Pb based sealing materials. So, we added $TiO_2$ as a promoter for bonding strength. We examined the effect of $TiO_2$ addition on sealing behaviors of $ZnO-V_2O_5-P_2O_5$ glasses with the data for flow button, wetting angle, temporary & permanent residual stress of glass substrate, EPMA analysis of interface between sealing materials and glass substrate, and bonding strength. As a result, sealing characteristics of $ZnO-V_2O_5-P_2O_5$ system glasses were improved with $TiO_2$ addition, but showed a maximum value at 5 mol% $TiO_2$ addition. The reason for improved bonding characteristics was considered to be the chemical interaction between glass substrate and sealing glass, and structural densification of sealing glass itself.

• 조명전기설비학회논문지
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• 제13권1호
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• pp.1-8
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• 1999

최근 들어 레이저를 이용한 방전 제어 기술에 대한 관심이 여러 분야에서 고조되고 있다. 특히, 레이저의 우수한 특성 때문에 Electro-Discharge Machining(EDM)분야에서 각광을 받고 있다. 본 연구에서는 펄스형 Nd:TAG 레이저를 이용해서 방전 가공 장치에 적용될 수 있는 방전 유도 기술에 관한 기초 데이터의 확보를 위한 실험이 수행되었다. 레이저에 의한 직류 발전 유도 실험의 동작 압력의 범위는 0.2~20 torr였다. 진공조 내의 압력 P와 전극간의 거리 d에 따른 최소 직류 레이저 방전 유도 전압 $V_{G.min}$을 측정하였으며, $V_{G.min}$이 자연 방전전압 VND보다 훨씬 낮고 P.d값에 따른 $V_{G.min}$이 $V_{ND}$와 유사한 경향을 가짐을 확인하였다. 그리고 레이저 출력 에너지 $E_{out}$은 플래쉬램프의 전류 펄스폭 $t_p$가 증가함에 따라 감소하고 $t_p$값이 증가할수록 $V_{G.min}$은 방전 지속 시간 동안에 조사되는 광자량이 감소하기 때문에 더 높아짐을 알 수 있었다. 또한 레이저에 의한 방전 유도 가능범위와 레이저 출력에 따른 방전 유도 특성을 조사하였다.

• 한국결정학회지
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• 제10권1호
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• pp.1-8
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• 1999

Two conformational isomers of p-tert-butylcalix[4]arene hexanoate were prepared from the reaction of-p-tert-butylcalix[4]arene and hexanoly chloride in the presence of AlCl3 in CH2Cl2 and their structures were determined by NMR spectra and X-ray diffraction as a cone and a 1,3-alternate conformer, respectively. The crystal of cone conformer (C68H96O8·(CH3)2CO) is triclinic, P, a=15.066(1) , b=16.063(1) , c=16.365(1) , α=79.75(2)o, β=109.95(2)o, γ=80.32(0)o, V=3602.7(4) 3, Z=2. The intensity data were collected on Simens SMART diffractometer/CCD area detector. The structure was solved by direct method and refined by least-squares calculations to a final R value of 0.144 for 4638 observed reflections. The molecular conformation is distorted symmetric cone with the flattening A and D phenyl rings. The crystal of 1,3-alternate conformer (C68H96O8·2CHCl3) is orthorhombic, Pca21, a=34.586(5) , b=10.207(3) , c=20.394(4) , V=7199(3) 3, Z=4. The intensity data were collected on an Enraf-Noninus CAD-4 Diffractometer with a graphite monochromated Mo-K radiation. The structure was solved by direct method and refined by least-squares calculations to a final R value of 0.152 for 2241 observed reflections. The molecule has a pseudo mirror symmetric 1,3-alternate conformation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.183-186
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• 1990

The lattice mismatch between ZnS and Si is negligible because of its value being 0.39%. In this study, $ZnS/_{(P)}Si$ solar cell were fabricated as a layer of ZnS is epitaxially grown on a silicon substrate by PVD method and its photovoltaic properties were measured and discussed. The heat treatment was done after deposition. As the temperature increased up to a certain value, the film has better perfection in crystal structure and electrical characteristics. Measurments of the change that occur in the ZnS films were made by SEM., X-ray diffraction. The optimal thickness of film showned $0.6{\mu}m$, being measured by SEM. The great improvement of the grain growth ZnS film came out after heat-treatment. The result obtained from the $ZnS/_{(P)}Si$ solar cell as follows:short circuit current; $I_{sc}=54mA/cm^2$,open voltage; $V_{oc}=400mV$, fill factor FF=0.72, conversion efficiency; ${\eta}=15.6%$ under the irradiation of 100 ($mW/cm^2$) focused by solar energy. And these are discussed in comparison with other kinds.

• 한국축산식품학회지
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• 제31권4호
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• pp.588-595
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• 2011

본 실험은 홍삼추출물의 농도별 처리를 통한 저염, 저지방 소시지 개발을 위하여 무처리(C), 아스코르빈산 나트륨 0.1%(V), 홍삼추출물(RGE) 0.5%(T1), 1%(T2) 및 1.5% (T3)를 첨가하여 품질 평가를 실시하였다. pH, 가열감량, CIE $b^*$은 T3처리구가 다른 시험구보다 높게 나타났으며(p<0.001). 명도(CIE $L^*$) 및 적색도(CIE $a^*$)는 낮게 낮아졌다(p<0.001). 또한, T3이 C보다 경도(hardness) 및 표면경도(surface hardness)가 낮게 나타났으나(p<0.01), 응집성(cohesiveness)은 RGE처리구가 높게 나타났다(p<0.05). 관능검사 측정결과 향기에서 T2 및 T3이 C 및 V보다 높게 나타내었지만(p<0.05), 육색, 맛, 조직감, 다즙성 및 종합적인 기호도는 시험구간 유의적인 차이를 나타내지 않았으며, 저장 1, 2 및 3주차의 TBARS에 있어 T3가 다른시험구보다 유의적으로 높게 나타났으나(p<0.01), T2 및 T3는 저장기간 동안 TBARS의 유의적인 변화가 나타내지 않았다(p>0.05). VBN 및 총균수는 저장 3 및 4주차에는 RGE처리구가 C보다 유의적으로 낮게 나타났다(p<0.01). 이상의 결과, 1% 이상의 RGE첨가구가 지방산화, 향기, 미생물학적 측면에서 우수한 결과를 나타내었다.

• Applied Biological Chemistry
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• 제50권3호
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• pp.154-159
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• 2007

제주산 병귤을 침출주의 소재로 활용하기 위하여 $30{\sim}95%$ 주정농도에 건조과피를 각각 500 g/10 l(5%, w/v) 비율로 첨가하여 70일간 침출특성을 검토하였다. 주정농도 30%에서 pH는 $5.19{\sim}4.80$으로 가장 낮았으며, 침출 후 10일까지 주정농도가 낮을수록 감소하는 경향이었다. 주정농도가 높을수록 색도 a값이 낮아지고, b값이 증가하였다. 가용성고형물은 주정농도 $30{\sim}70%$에서 $2.00{\sim}2.19%(w/v)$로, 지속적으로 증가하는 경향이었다. 산함량은 주정농도 $30{\sim}70%$에서 $0.18{\sim}0.21%(v/v)$로 차이가 거의 없었으며, 주정농도 95%에서는 $0.13{\sim}0.15%(v/v)$였다. 주정농도 낮을수록 fructose와 glucose가 많았으며, 침출기간이 길어질수록 sucrose 함량은 낮았다. 병귤과피의 주요 flavonoid는 narirutin, hesperidin, nobiletin, 3,5,6,7,8,3'4'-methoxylated flavone, tangeretin이었고, 대부분의 flavonoids는 침출 후 $3{\sim}5$일에 80%이상 용출되었다. 총 폴리페놀 함량은 주정농도 $30{\sim}70%$로 20일 침출에서 $628.8{\sim}711.2$ ${\mu}g/ml$였으며, 주정원액에서 가장 높은 함량을 나타내었다. 따라서 병귤과피를 침출주 원료로 사용하였을 때, 주정농도 $50{\sim}70%$에서 20일 동안 침출시키는 방법이 효과적이었다.

• International Journal of Railway
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• 제1권2호
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• pp.64-71
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• 2008

The quality of track-bed fills of railways has been controlled by field measurements of density $({\gamma}_d)$ and the results of plate-load tests. The control measures are compatible with the design procedures whose design parameter is $k_{30}$ for both ordinary-speed railways and high-speed railways. However, one of fatal flaws of the design procedures that there are no simple laboratory measurement procedures for the design parameters ($k_{30}$ or, $E_{v2}$ and $E_{v2}/E_{v1}$) in design stage. A new quality control procedure, in parallel with the advent of the new design procedure, is being proposed. This procedure is based upon P-wave velocity involving consistently the evaluation of design parameters in design stage and the field measurements during construction. The Key concept of the procedure is that the target value for field compaction control is the P-wave velocity determined at OMC using modified compaction test, and direct-arrival method is used for the field measurements during construction. The procedure was verified at a test site and the p-wave velocity turned out to be an excellent control measure. The specifications for the control also include field compaction water content of OMC${\pm}$2% as well as the p-wave velocity.

• 한국환경과학회지
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• 제13권3호
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• pp.245-250
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• 2004

The SBR(Sequencing Batch Reactor) process is ideally suited to treat high loading wastewater due to its high dilution rate. SBR operates by a cycle of periods consisting of filling, reacting, settling, decanting and idling. The react phases such as aeration or non-aeration, organic oxidation, nitrification, denitrification and other bio-logical reactions can be achieved in a reactor. Although the whole reactions can be achieved in a SBR with time distributing, it is hard to manage the SBR as a normal condition without recognizing a present state. The present state can be observed with nutrient sensors such as ${NH_{4}}^{+}-N$, ${NO_{2}}^{-}-N$, ${NO_{3}}^{-}-N} and ${PO_{4}}^{ 3-}-P.$ However, there is still a disadvantage to use the nutrient sensors because of their high expense and inconvenience to manage. Therefore, it is very useful to use common on-line sensors such as DO, ORP and pH, which are less expensive and more convient. Moreover, the present states and unexpected changes of SBR might be predicted by using of them. This study was conducted to get basic materials for making an inference of SBR process from ORP(oxidation reduction potential) of synthetic wastewater. The profiles of ORP, DO, and pH were under normal nitrification and denitrification were obtained to compare abnormal condition. And also, nitrite and nitrate accumulation were investigated during reaction of SBR. The bending point on ORP profile was not entirely in the low COD/NOx ratio condition. In this case, NOx was not entirely removed, and minimum ORP value was presented over -300mV. Under suitable COD/NOx ratio which complete denitrification was achieved, ORP bending point was observed and minimum ORP value was under -300m V. Under high COD/NOx ratio, ORP bending point was not detected at the first subcycle because of the fast denitrification and minimum ORP value was under -300mV at the time.