• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.112-112
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• 2008

박막형 태양전지에 관한 연구는 1954년 D.C. Reynolds 가 단결정 CdS 에서 광기전력을 발견하면서부터 시작되었다. 고효율 단결정 규소 태양전지가 간편하게 제작되고 박막형 태양전지의 수명문제가 대두되어 한때는 연구가 중단되어지기도 하였으나, 에너지 문제가 심각해지면서 값이 저렴하고 넓은 면적에 쉽게 실용화 할 수 있는 박막형 태양전지에 많은 관심을 가지게 되었다. 박막형 태양전지에 사용되는 CdS는 II-VI 족 화합물 반도체로서 에너지금지대폭이 2.42eV인 직접천이형 n-type 반도체로서 대부분의 태양광을 통과시킬 수 있으며 가시광선을 잘 투과시키고 낮은 비저항으로서 광흡수층인 CdTe/$CuInSe_2$ 등과 같이 태양전지의 광투과층(윈도레이어)으로 널리 사용되고 있다. 이러한 이종접합 박막형 태양전지의 효율을 높이기 위해선 윈도레이어 재료인 CdS 박막의 낮은 전기 비저항치와 높은 광 투과도 값이 요구되어지고 있다. CdS 박막의 제작방법으로는 spray pyrolysis법, 스크린프린팅, 소결법, puttering법, 전착법, CBD(chemical bath deposition)법 및 진공증착법 등의 여러 가지 방법들이 보고되었다. 이 중 sputtering의 경우, 다른 방법들에서는 얻기 어려운 매우 얇은 두께의 박막 증착이 가능하며, 균일성 또한 우수하다. 또한 대면적화가 용이하여 양산화 기술로는 다른 제조 방법들에 비해 많은 장점을 가지고 있다. 따라서 본 연구에서는 sputtering에 의해 증착한 CdS의 박막에 광투과도 등의 향상을 위하여 CMP( chemical mechanical polishing) 공정을 적용하여 표면 특성을 개선하고자 하였다. 그 기초적인 자료로서 CdS 박막의 CMP 공정 조건에 따른 연마율과 비균일도, 표면 특성 등을 ellipsometer, AFM(atomic force microscopy) 및 SEM(scanning electron microscope) 등을 활용 하여 분석하였다.

• Toxicological Research
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• v.32 no.4
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• pp.301-309
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• 2016

Due to undesirable hazardous interactions with biological systems, this investigation was undertaken to evaluate the effect of chronic exposure to silver on certain biochemical and some oxidative stress parameters with histopathological examination of brain, as well as the possible protective role of selenium and/or vitamin E as nutritional supplements. Thirty six male rats were divided into six groups of six each: the first group used as a control group. Group II given both vitamin E (400 mg/kg) of diet and selenium (Se) (1 mg/L) in their drinking water. Group III given silver as silver nitrate ($AgNO_3$) (20 mg/L). Group IV given vitamin E and $AgNO_3$. Group V given both $AgNO_3$ and selenium. Group VI given $AgNO_3$, vitamin E and Se. The animals were in the same exposure conditions for 3 months. According to the results which have been obtained; there was an increase in serum lactate dehydrogenase (LDH), lipase activities and cholesterol level, a decrease in serum total protein, calcium and alkaline phosphatase (ALP) activity in Ag-intoxicated rats. Moreover, the findings showed that $Ag^+$ ions affected antioxidant defense system by decreasing superoxide dismutase (SOD) activity and increasing vitamin E concentration with a high level of malondialdehyde (MDA) in brain tissue. The histological examination also exhibited some nervous tissue alterations including hemorrhage and cytoplasm vacuolization. However, the co-administration of selenium and/or vitamin E ameliorated the biochemical parameters and restored the histological alterations. In conclusion, this study indicated that silver could cause harmful effects in animal body and these effects can be more toxic in high concentrations or prolonged time exposure to this metal. However, selenium and vitamin E act as powerful antioxidants which may exercise adverse effect against the toxicity of this metal.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.464-468
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• 2017

The identification of pork in commercially processed meats is one of the most crucial issues in the food industry because of religious food ethics, medical purposes, and intentional adulteration to decrease production cost. This study therefore aimed to develop a method for the detection of pork adulteration in meat products using primers specific for pig mitochondrial DNA. Mitochondrial DNA sequences for pig, cattle, chicken, and sheep were obtained from GenBank and aligned. The 294-bp mitochondrial DNA D-loop region was selected as the pig target DNA sequence and appropriate primers were designed using the MUSCLE program. To evaluate primer sensitivity, pork-beef-chicken mixtures were prepared as follows: i) 0% pork-50% beef-50% chicken, ii) 1% pork-49.5% beef-49.5% chicken, iii) 2% pork-49% beef-49% chicken, iv) 5% pork-47.5% beef-47.5% chicken, v) 10% pork-45% beef-45% chicken, and vi) 100% pork-0% beef-0% chicken. In addition, a total of 35 commercially packaged products, including patties, nuggets, meatballs, and sausages containing processed chicken, beef, or a mixture of various meats, were purchased from commercial markets. The primers developed in our study were able to detect as little as 1% pork in the heat treated pork-beef-chicken mixtures. Of the 35 processed products, three samples were pork positive despite being labeled as beef or chicken only or as a beef-chicken mix. These results indicate that the developed primers could be used to detect pork adulteration in various processed meat products for application in safeguarding religious food ethics, detecting allergens, and preventing food adulteration.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.355-365
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• 1991

This study was conducted in order to observe the changes in cellular association of seminiferous tubules from 16 to 24 weeks of age and to obtain the cycle and relative duration of the seminiferous epithelia from 28 to 44 weeks of age in Korean native dogs. The results were summarized as follows; 1. Gonocytes were seen at 16 weeks of age, however they were not observed as from 20 weeks of age. Both type A and type B-spermatogonia occurred from 20 weeks, while primary spermatocytes were found from 20 weeks. Secondary spermatocytes and spermatids appeared from 28 weeks. Spermatozoa were observed at first at 28 weeks of age. 2. Type A-spermatogonia appeared approximately 1.6 times as many at stage II compared to stage I, while the same numbers of cells were seen in both stage I and VII, showing the least number among VIII stages of the cycle of the seminiferous epithelia. The type B-spermatogonia were found from stage VI to VIII, Leptotene phase of the primary spermatocyte divided from type B-spermatogonia in stage VII observed at the stage VIII. Pachytene phase of the primary spermatocytes were shown the least in number at stage IV. The secondary spermatocyte could be seen only at stage IV. 3. The relative frequency of each stage from stage I to VIII of the cycle of the seminiferous epithelia was 30.3, 12.0, 9.8, 4.2, 8.5, 10.5, 11.4 and 13.4% respectively. Thus the establishment of spermatogenesis in Korean native dog was completed from 28 weeks of age.

• Korean Journal of Veterinary Research
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• v.39 no.5
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• pp.995-1005
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• 1999

Staphylococcus aureus is one of most prevalent intramammary pathogens and have characteristics which are not easily eradicated. Recently, to understand the sources and transmission of S aureus, many studies have focused on the subtyping of field isolate. This study was preformed to investigate the distribution pattern and characteristics of the isolates using phenotyping and genotyping. Samples were collected from milk of each udder, cow bodies (perianal region, vagina, tail, udder skin, sole) and environment (floor, liner, milker's hands, water, towel, insect) from 6 herds located in Kyung-gi province. Forty five strains of S aureus were isolated from 3 dairy herds (A, B, C) and were typed by hemolytic pattern, antibiotic resistant pattern, enterotoxin typing and PCR-based DNA fingerprinting. Slime productivity was also compared by each subtype to examine potential infectiousness. Of 45 strains, 41 were isolated from milk samples and 4 were isolated from liners. No strains isolated in the bodies and environment. Forty five strains isolated were classified as 18 subtypes by phenotyping and genotyping. There was common subtype between A and B herd, but the subtype of C herd showed different pattern. Among predominant subtypes, 60% of S aureus strain isolated from A and B herd showed subtype I and 50% of S aureus strain isolated from C herd belonged to subtype VI and X II. Neither somatic cell count (SCC) nor slime production was significantly different between predominant and minor subtypes. In summary, the study revealed that liners play more important roles in the mode of transmission than environmental sources. Several subtypes can be found in a herd, only a few subtype, however, was largely associated with the majority of infection.

• Journal of Korean Association for Spatial Structures
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• v.17 no.4
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• pp.59-68
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• 2017

This paper aims at finding some lessons applicable to successful implementation of 'The 3D Printing R/D Project' through both examining the process of adopting overseas industrialized housing production technological knowhow by home builders during the 1970's~1980's period and thereafter until now the various efforts to adjust the technologies efficiently to the Korea's unique situation. Some meaningful lessons can be summarized as follows; I) Deep understanding of 3DP technological know-why along with its inheritance, II) Readjusting of R/D period and goals(cf. Global leader Winsun's 15 years experiment), III) Restructuring for more collaborative R/D B&E system among participating researchers IV) Fostering 3DP expert-engineers and technicians from the early stage, V) Clearing legal barriers in users' adopting 3DP methods necessary, VI) Development of appropriate building material besides concrete. Therefore, it is highly recommended that the above-mentioned 6 lessons positively accepted and applied to the Research Implementation Plan in due course, especially by KICT consortium and KAIA under the guidance of Ministry of Land, Infrastructure and Transport.

• Journal of Arbitration Studies
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• v.17 no.2
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• pp.71-100
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• 2007

To promote the way of resolving the increasing disputes regarding international intellectual property by arbitration, we should overcome uncertainty thwarting the dispute resolution; i.e., whether a dispute regarding intellectual property would be an arbitrable subject, whether the arbitration agreement would be valid and enforceable, and whether the arbitral award could be recognized and enforced in a foreign country. This article is intended to seek how to promote and facilitate the resolution of international disputes regarding intellectual property by arbitration. This article in Chapter II will examine the characteristics of the IP disputes first. Chapter III of this article will study arbitrability of IP disputes. Then, Chapter IV will discuss the requirements, validity, and effectiveness of arbitration agreement of international IP disputes. The author will discuss the procedure of arbitration of the international IP disputes in Chapter V, and finally the recognition and enforcement of foreign arbitral awards thereon in Chapter VI. Due to the so called 'territoriality principle' in intellectual property, the international disputes thereof confront numerous procedural setback, e.g., jurisdiction, conflict of laws, the recognition and enforcement of foreign judgments or awards. To overcome such setbacks, I propose resolution of international IP disputes by one-step arbitration procedure through widely recognizing the arbitrability of IP disputes, and utilizing unnational nature of arbitration. In addition, I propose to set up the principles as to arbitration of the international IP disputes as the American Law Institute has formulated the principles for International Intellectual Property Litigations. By setting up these principles, I am certain it will be helpful to just and prompt resolution of international IP disputes which occur more frequently these days.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.8
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• pp.1038-1045
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• 2000

An experimental study was carried out to delineate the flow characteristics in a closed countescurrent two-phase thermo syphon with concentric tubes. This is to be installed in the HANARO research reactor as a part of a Cold Neutron Source(CNS). In the present investigation, experiments ata room temperature with Freon-II3 as a moderator were performed. Results show that, based on the magnitude of pressure fluctuation, the flow regimes could be divided into 4 distinct ones in the ($V_f,\;Q_i$) plane, where $V_f$ represents the volume of the charged liquid and $Q_i$ the heat load: a stable flow regime, an oscillatory flow regime, a restablized flow regime and a dryout flow regime. For $V_f$>2.5l, the flow is stable at low $Q_i$. However, as $Q_i$ increases, the flow becomes oscillatory and finally restablizes As $V_f$ increases, the oscillation amplitude decreases, reaching to the restablized flow region at low $Q_i$, and the liquid level in the moderator cell remains high. In the oscillatory flow regimes, for a fixed VI; the oscillating period of time varies with $Q_i$, having a minimum value at a certain value of $Q_i$. The heat load, where the oscillating period of time is minimum, decreases as $V_f$ increases.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.838-844
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• 2008

This experiment was conducted to evaluate the effect of supplementing a fat diet with selenium (Se) and vitamin E on performance of cows, blood antioxidant status and milk fatty acid composition. Sixty-three lactating Holstein cows were randomly divided into seven groups of nine cows each and each group was fed one of the following diets: i) a basal diet (control); ii) a basal diet with 0.15 mg Se/kg DM (LSe); iii) a basal diet with 0.3 mg Se/kg DM (HSe); iv) a basal diet with 5,000 IU/cow d vitamin E (LVE); v) a basal diet with 10,000 IU/cow d vitamin E (HVE); vi) a basal diet with 0.15 mg Se/kg DM and 5,000 IU/cow d vitamin E (LSeVE); vii) a basal diet with 0.3 mg Se/kg DM and 10,000 IU/cow d vitamin E (HSeVE). Milk fat percentage and conjugated linoleic acid (CLA) yield in HVE and HSeVE diets increased (p<0.05) compared with the control diet. In milk fat, dietary supplementation of Se tended to increase the proportion of the sum of unsaturated fatty acids (UFA) and significantly decreased (p<0.05) the proportion of the sum of saturated fatty acids (SFA). In addition, compared with the control, thiobarbituric acid reactive substances (TBARS) content was lower and glutathione peroxidase (GSH-Px) was higher when fat diets were supplemented with Se. Our data showed that supplementation with Se and/or VE improved these nutrients in blood and milk. The results indicated that fat diets supplemented with Se improved both antioxidant status in blood and fatty acids in milk fat, and fat diets supplemented with vitamin E alleviated milk fat depression. Therefore, the combination of Se and vitamin E caused synergistic effects on the nutritional quality of milk fat and performance of cows fed a fat diet.

• Herbal Formula Science
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• v.20 no.2
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• pp.137-151
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• 2012

Objectives : provides the basis on steaming processing method (SPM) which was stated in 'Dongeuibogam' and 'Euihakipmun'. Methods : Drugs and prescriptions listed in 'Dongeuibogam' and 'Euihakipmun' were investigated by following criteria; (i) name and prescription of SPM-applied drugs, (ii) protocols on the use of the supporting materials, (iii) kind of supporting materials, (iv) processing period, (v) part of the herb plants, (vi) efficacy of herbal drugs, (vii) tastes of herbal drugs, (viii) meridian tropism of the herbal drugs. Results : 1. The number of herbs was 92 species of from 'Dongeuibogam', 87 from 'Euihakipmun', and the number of prescriptions was 197 from 'Dongeuibogam' and 119 from 'Euihakipmun'. 2. Infiltrating steaming and mixing and steaming procedures were used to process supporting materials. 3. The abundance of supporting materials was in the order of alcohol and ginger juice. 4. A twelve hour-period was most frequently used. 5. The herbal parts used most were in the order of fruit, seed, roots, and stem. 6. According to an efficacy category, a drug supplementing invigoration was used most frequently and a drug eliminating heat followed next. 7. Based on four spirit features, herbs showing warm, cold, and mild features were used most. 8. In considering five tastes, herbs showing sweet and bitter tastes were used most. 9. The herbs supporting the function of liver, kidneys, spleen, stomach, and lung were used in SPM. The herbs converging to the kidneys and the liver were conducted most in 'Dongeuibogam' and 'Euihakipmun' respectively. No case for herbal drug converging to 'Samcho' was reported. Conclusions : Our investigation on the use of SPM from 'Dongeuibogam' and 'Euihakipmun' revealed that there are special principles underlying the use of supporting materials, SPM period, parts and efficacy.