• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.205-208
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• 2005

최근 열선 화학 기상 증착법(HWCVD)은 낮은 온도에서 TFT용 Poly Si 중착을 할 수 있다는 점과 실리콘 박막을 빠른 속도로 증착할 수 있다는 점에서 각광을 받고 있다. 본 연구에서는 HWCVD를 이용하여 태양전지를 제조하고 그 특성을 평가하였다. 조건에 따른 실리콘 박막의 특성 변화를 알기 위해 corning glass 및 실리콘 wafer에 다양한 조건에서 단위 박막(intrinsic layer)을 증착하였고 이 결과를 바탕으로 p/i/n 구조의 태양전지를 제조하였다. Ta 열선 온도는 1700-2000도였고 가스 원료인 $SiH_4$와 수소의 비율을 조절하면서 그 영향을 관찰하였다. 태양전지의 경우 p충과 n충은 PECVD로 증착하였으며 단위박막 및 태양전지 i충 증착시 기판과 열선간의 거리는 7cm, 기판 온도는 $200^{\circ}C$와 $250^{\circ}C$로 고정하였고 작업압력은 30mTorr였다. 단위 박막 특성 평가를 위해 암/광 전도도, SEM, Raman Scattering, FT-IR등을 사용하였으며 태양전지 특성 평가를 위해 I-V 및 Spectral response를 측정하였다. 열선 온도가 증가함에 따라 증착속도 및 결정화 분율은 증가하였다. 특히 비정질에서 결정질로 전이되는 구간은 매우 좁았으며 여러 분석 방법에서 일치되는 결과를 보였다. $SiH_4$ 유량이 늘어날수록 비정질이 결정질로 바뀌는 열선 온도가 증가하였으며 기판 온도가 낮을 경우 또한 결정으로 바뀌는 열선 온도가 증가하였다. 태양전지의 경우 열선 온도가 증가함에 따라 $V_{oc}$ 및 W가 낮아졌으며 $J_{sc}$, 는 증가하는 경향을 보였으며 결정질 비율이 증가하는 것을 관찰할 수 있었다. 이러한 경향은 quantum efficiency 결과에서도 확인할 수 있었다.용을 반복하면서 석재 내부와 외부의 암석 및 결정에 균열과 미세열극 등이 생성되어 석재 자체의 구조적 안정성에 영향을 주고 있다. 따라서 감은사지 석탑은 지리적 환경 차이로 인해 일반적인 환경의 석조물들과는 다른 형태의 풍화양상을 보이고 있어서 풍화양상 및 풍화형태에 대한 정확한 연구와 이해를 바탕으로 보존대책이 마련되어야 한다.되었다. 이런 모든 시편들을 각 탈염방법에 따라 탈염처리한 후 XRD와 SEM-EDS으로 분석한 결과 인철광과 침철광은 어떠한 변화도 보이지 않았고, 다만 적금광으로 동정된 시편만이 잔존하지 않았다. 철기 제작별 $Cl^-$ 이온 추출량과 탈염효과에 대한 비교 실험은 이온 크로마토그래피 분석 결과와 마찬가지로 단조 철제유물이 주조 철제보다 $Cl^-$ 이온을 많이 가지고 있었으며, 탈염 처리 후에는 $Cl^-$ 이온은 전혀 발견되지 않았다. 이상의 결과 $K_2CO_3$와 Sodium 용액은 탈염처리에서 가장 적합한 탈염처리 용액으로 알수가 있었으며 특히 어떠한 탈염 용액으로 유물을 처리한다 해도 철제유물에 생성된 부식물은 제거되지 않는다는 것을 알게 되었다. 따라서 보존처리자는 유물 표면의 부식 상태만을 보고 처리하기 보다는 철기제작물로 고려하여 처리하는 것이 필요하다. 또한 금속에 부식을 야기시키는 $Cl^-$ 이온과 부식물을 완전하게 제거하여 탈염처리를 하는 것이 유물 부식을 최대한 지연시킬 수 있는 것이라 생각된다.TEX>$88\%$)였다.(P=0.063). 결론: 본 연구에서는 MTHFR C/T & T/T 유전자 다형성이 위암의 발생과 그 위치에 대해 관련이 있는 것으로 여겨지고, 흡연력, 음주력과는 관련이 없는 것으로 여겨진다.험이 커지는 경향을 보였으나, 나이 및 병기, 종양의 크기, MD-BED $Gy_{10}$ 등의 예후 인자를 보정한 다변

• Pediatric Infection and Vaccine
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• v.23 no.2
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• pp.109-116
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• 2016

Purpose: Recent observational studies have found that vitamin D deficiency is associated with respiratory tract infections. However, randomized controlled trials (RCTs) regarding the efficacy of vitamin D in childhood respiratory tract infection (RTI) have yield inconsistent results. We performed a systematic review and meta-analysis to evaluate the association between vitamin D supplementation and the risk of RTI. Methods: A comprehensive search was conducted using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trial. Randomized controlled trials of vitamin D supplementation for prevention of RTI in children were included for the analysis. Cochrane Collaboration's tool for assessing the risk of bias was used to assess the quality of the studies. Pooled risk ratios with 95% confidence intervals (CIs) were meta-analyzed using Review Manager 5.3. Results: A total of seven RCTs were included in the meta-analysis. According to a random-effects model, the risk ratio for vitamin D supplementation was 0.82 (95% CI: 0.69-0.98) and $I^2=62%$ for heterogeneity. On subgroup analysis, heterogeneity decreased in the subgroup with follow-up less than 1 year, participants ${\geq}5years$ of age, patients subgroup, and subgroup with dosing daily. Funnel plot showed that there might be publication bias in the field. Conclusions: The present meta-analysis supports a beneficial effect of vitamin D supplementation for the prevention of RTI in children. However, the result should be interpreted with caution due to limitations including a small number of available RCTs, heterogeneity among the studies, and potential publication bias.

• Korean Journal of Environmental Agriculture
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• v.14 no.3
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• pp.329-337
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• 1995

The effect of N-(4-chlorophenyl) maleimide(CPMI), plant growth regulators, and alkylating agents on gluathione(GSH) content and glutathione S-transferase(GST) activity was examined with 3-day-old etiolated sorghum(Sorghum bicolor [L.] Moench) seedlings. The GSH content and GST activity of untreated seedlings were higher in shoots than that in roots. Response of GST activity in coleoptile was significantly greater than in other tissues of sorghum seedling. In CPMI-treated seedlings, GSH content was not significantly different from that in untreated seedlings. CPM treatment resulted in 2.3-fold increase in GST activity measured with metolachlor as substrate in the coleoptile region. In contrast, change in GST activity measured with metolachlor as substrate in the coleoptile region. In contrast, change in GST activity measured with 1-chloro-2, 4-dinitrobenzene did not occur. The increase of GST activity was caused by induction of a GST isozyme, which is substrate-specific to metolachlor. Subsequently, two hypotheses related to metolachlor detoxification were evaluated on the basis of regulation of plant growth regulators and substrate induction of GST activity. In coleoptile, GST activity measured with metolachior was increased to 2.1-and 3.4-fold by both 2, 4-dichlorophenoxyacetic acid(2,4-D) and metolachlor treated at the germination stage of sorghum, respectively. Treatments of 2.4-D and metolachlor also induced isozymes exhibiting the activity toward metolachlor. One of the isozymes was co-eluted with that induced by CPMI. These results indicated that increase in GST activity by CPMI may be partially related to auxin regulation and substrate induction.

• Food Science and Preservation
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• v.15 no.6
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• pp.891-896
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• 2008

Total phenolics and flavonoids, and the antioxidant capacity of plum cultivar wines (Prunus salicina L. cv. Soldam and P. salicina L. cv. Formosa) were determined using spectrophotometric methods. The total phenolic and flavanoid contents of Soldam wine were $478.4\;{\pm}\;5.6\;mg$ GAE and $202.4\;{\pm}\;7.5\;mg$ CE per L,respectively, and in Formosa wine were $200.6\;{\pm}\;7.5\;mg$ GAE and $64.4\;{\pm}\;6.8\;mg$ CE per L, respectively. Neutral and acidic phenolics in Soldam wine were extracted with ethyl acetate and 0.01 N HCl, respectively. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, neutral phenolics (64.5 EDA%) had $3{\sim}4$ times higher antioxidant activity than acidic phenolics (21.5 EDA%) and other related phenolic compounds such as chlorogenic acid (15.5 EDA%) and quercetin (24.6 EDA%) at a concentration of $100\;{\mu}g/mL$. The antiviral activities of neutral and acidic phenolics in Soldam wine were investigated in vitro using a virus-induced cytopathic effect (CPE) inhibition assay. Results showed that neutral and acidic phenolics at concentrations of $100\;{\mu}g/mL$ inhibited porcine epidemic diarrhea virus (PEDV) replication at rates of 78.12% and 58.37%, respectively. The inhibition rate of 10 g/mL neutral phenolics (69.42%) was higher than that of ribavirin as an antiviral reagent (57.86%). At concentrations of $100\;{\mu}g/mL$ or less, neutral and acidic phenolics of Soldam wine had no cytotoxic effect against vero cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.282-291
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• 1994

Optimal processing conditions and shelf-life of steamed kamaboko made from Alaska pollock surimi were investigated, including protein digestibility, computed protein efficiency ratio (C-PER), trypsin inhibitor content and protein solubility. Steamed kamaboko containing $5\%$ starch and $33\%$ water in pollock surimi showed the best protein quality in terms of C-PER and protein digestibility. Steaming could not give any significant advantage over kamaboko protein digestibility but a higher C-PER resulted from steamed kamaboko. All kamaboko products had trypsin content of 1.4 to $2.0mg\%$ which was $10\%$ of total trypsin inhibitor levels in frozen pollock meat. A two stage steaming process, the first at $40^{\circ}C$ for 20min followed by a second 10min steaming period at $95^{\circ}C$, was found to be the most effective way of the most effective heating process for kamaboko protein quality. C-PERs of marketed Korean surimi products ranged from $2.8{\sim}2.9$ for steamed kamaboko and $2.9{\sim}3.2$ for crab meat analog which were superior to ANRC casein(2.5). Measured protein digestibility of all products were ranged from 86 to $89\%$. VBN and protein solubility data suggest Korean marketed surimi products could have a shelf-life of 15 days at $4^{\circ}C$ for crab meat analog and 20 days at $4^{\circ}C$ for steamed kamaboko.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.223-231
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• 1994

In order to develop the squid(Todarodes pacificus) sik-hae, the changes of TBA, fatty acids, free amino acids, and the number of microflora fermented at different fermentation temperatures and periods were determined. In addition, pretense from squid sik-hae was partially purified. The number of TBA was the highest after 5-day storage and decreased after that, and lipid oxidation was the highest at $10^{\circ}C$. The amounts of linoleic aid(18:2) and oleic acid (18:1) were about $60\%$ of fatty acid composition of squid sik-hae, and linolenic acid(18:3) and EPA(20:5) significantly decomposed with increasing fermentation periods and temperatures. Pro, His, Aeg, Leu, and Glu were composed mainly of amino acid and the composition ratios of Ser, His, and Arg decreased with increasing fermentation periods whereas, those of Glu, Ala, Val, and Tyr increased. The composition ratios of Glu, Val, and Met increased with increasing fermentation temperatures whereas, those of Ala, Cys, Thr, and Gly decreased. The number of microflora generally increased up to 15-days of storage and decreased after that. The rates of increass and decreass of the microbial number increased in proportion to fermentation temperatures. In addition, the bacteria producing proteases were identified as Bacillus spp. Proteases from $60{\sim}80\%$ ammonium sulfate concentration showed the highest activity and had about 15 binds with molecular weights between 20,000 and 40,000 Dalton by the SDS-PAGE.

• Proceedings of the KSRS Conference
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• 2001.03a
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• pp.140-148
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• 2001

The satellite sensor model is typically established using ground control points acquired by ground survey Of existing topographic maps. In some cases where the targeted area can't be accessed and the topographic maps are not available, it is difficult to obtain ground control points so that geospatial information could not be obtained from satellite image. The paper presents several satellite sensor models and satellite image decomposition methods for non-accessible area where ground control points can hardly acquired in conventional ways. First, 10 different satellite sensor models, which were extended from collinearity condition equations, were developed and then the behavior of each sensor model was investigated. Secondly, satellite images were decomposed and also pseudo images were generated. The satellite sensor model extended from collinearity equations was represented by the six exterior orientation parameters in 1$^{st}$, 2$^{nd}$ and 3$^{rd}$ order function of satellite image row. Among them, the rotational angle parameters such as $\omega$(omega) and $\phi$(phi) correlated highly with positional parameters could be assigned to constant values. For non-accessible area, satellite images were decomposed, which means that two consecutive images were combined as one image. The combined image consists of one satellite image with ground control points and the other without ground control points. In addition, a pseudo image which is an imaginary image, was prepared from one satellite image with ground control points and the other without ground control points. In other words, the pseudo image is an arbitrary image bridging two consecutive images. For the experiments, SPOT satellite images exposed to the similar area in different pass were used. Conclusively, it was found that 10 different satellite sensor models and 5 different decomposed methods delivered different levels of accuracy. Among them, the satellite camera model with 1$^{st}$ order function of image row for positional orientation parameters and rotational angle parameter of kappa, and constant rotational angle parameter omega and phi provided the best 60m maximum error at check point with pseudo images arrangement.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.950-955
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• 2007

Non-point source control system which had been designed only for oil-water separation in the fields of oil refinery and garage was upgraded in this research for the removal of runoff pollutants in impervious urban area. Pollutants including oil from driveway and bridge were eliminated by two types of pathway in the system. One is the coalescence mechanism that the oil droplets in the runoff come into contact with each other in the spiral buoyant media surface and form larger coalesced droplets of oil that are carried upstream to the oil layer. The other is the precipitation that solids in runoff were settled by gravity in the system. In this research, coalescing characteristics of oil and water separation were investigated through image analyses, and efficiencies of the non-point source control system were evaluated using dust in driveway and waste engine oil. Media made of high density and high molecular weight polyethylene was indeterminate helical shape and had sleek surface by analysing SEM photographs and BET. Surface area and specific gravity of media which were measured directly were 1,428 $mm^2$ and 45.3 $kg/m^3$ respectively. From the image analyses of the oil droplets photographs which were taken by using microscope, it was proved clearly that the coalescence was the main pathway in the removal of oil from the runoff. Finally, the performances of the non-point source control system filled up with the media were suspended solid $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane extractable materials $71.8\sim94.8%$ respectively.

• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.673-679
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• 2015

In vitro antioxidant activities and neuronal cell protective effects of the ethyl acetate fraction of a new green extract (Brassica oleracea var. botytis aut italiana) against $H_2O_2$-induced oxidative stress were investigated, and its industrial feasibility was evaluated. The extract showed the highest contents of total phenolic compounds among other extracts as well as a 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity and malondialdehyde (MDA) inhibitory effect. This extract not only decreased the intracellular reactive oxygen (ROS) level but also protected the neuronal cells against $H_2O_2$-induced oxidative stress. On analysis using gas chromatograph-mass spectrometry, the following phenolic compounds were identified: quinic acid, ferulic acid, and caffeic acid. Collectively, these results suggest that this new green extract could contain functional substances that would help prevent the risk of neurodegenerative disease.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.633-640
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• 2011

Brassica rapa is an A genome model species for Brassica crop genetics, genomics, and breeding. With the completion of sequencing the B. rapa genome, functional analysis of the genome is forthcoming issue. The expressed sequence tags are fundamental resources supporting annotation and functional analysis of the genome including identification of tissue-specific genes and promoters. As of July 2011, 147,217 ESTs from 39 cDNA libraries of B. rapa are reported in the public database. However, little information can be retrieved from the sequences due to lack of organized databases. To leverage the sequence information and to maximize the use of publicly-available EST collections, the Brassica rapa tissue-specific EST database (BrTED) is developed. BrTED includes sequence information of 23,962 unigenes assembled by StackPack program. The unigene set is used as a query unit for various analyses such as BLAST against TAIR gene model, functional annotation using MIPS and UniProt, gene ontology analysis, and prediction of tissue-specific unigene sets based on statistics test. The database is composed of two main units, EST sequence processing and information retrieving unit and tissue-specific expression profile analysis unit. Information and data in both units are tightly inter-connected to each other using a web based browsing system. RT-PCR evaluation of 29 selected unigene sets successfully amplified amplicons from the target tissues of B. rapa. BrTED provided here allows the user to identify and analyze the expression of genes of interest and aid efforts to interpret the B. rapa genome through functional genomics. In addition, it can be used as a public resource in providing reference information to study the genus Brassica and other closely related crop crucifer plants.