• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.339-339
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• 2002

In the RABiTS approach to coated conductor development, successful (both economic and technological) depends on the refinement and optimization of each of three important components: the metal tape substrate, the buffer layer(s), and the HTS layer. Here we will report on the ORNL approach and progress in each of these areas. - Most applications will require metal tapes with low magnetic hysteresis, mechanical strength, and excellent crystalline texture. Some of these requirements are competing. We report on progress in obtaining a good combination of these characteristics on metal alloys of Ni-Cr and Ni-W. - The deposition of appropriate buffer layers is a crucial step. Recently, base research has shown that the presence of a stable sulfur superstructure present on the metal surface is needed for the nucleation and epitaxial growth of vapor-deposited seed buffer layers such as YSZ, CeO$_2$ and SrTiO$_3$. We report on the details and control of this superstructure for nickel tapes, as well as recent results for Cu and Ni-13%Cr. - Processes for deposition of the HTS coating must economically provide large values of the figure-of-merit for conductors, current x length. At ORNL, we have devoted efforts to a precursor/post-annealing approach to YBCO coatings, for which the deposition and reaction steps are separate. We describe motivation for and progress toward developing this approach. - Finally, we address some issues for the implementation of coated conductors in real applications, including the need for texture control and electrical stabilization of the HTS coating.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.258-258
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• 2016

최근 디스플레이 산업의 발전에 따라 고성능 디스플레이가 요구되며, 디스플레이의 백플레인 (backplane) TFT (thin film transistor) 구동속도를 증가시키기 위한 연구가 활발히 진행되고 있다. 트랜지스터의 구동속도를 증가시키기 위해 높은 이동도는 중요한 요소 중 하나이다. 그러나, 기존 백플레인 TFT에 주로 사용된 amorphous silicon (a-Si)은 대면적화가 용이하며 가격이 저렴하지만, 이동도가 낮다는 (< $1cm2/V{\cdot}s$) 단점이 있다. 따라서 전기적 특성이 우수한 산화물 반도체가 기존의 a-Si의 대체 물질로써 각광받고 있다. 산화물 반도체는 비정질 상태임에도 불구하고 a-Si에 비해 이동도 (> $10cm2/V{\cdot}s$)가 높고, 가시광 영역에서 투명하며 저온에서 공정이 가능하다는 장점이 있다. 하지만, 차세대 디스플레이 백플레인에서는 더 높은 이동도 (> $30cm2/V{\cdot}s$)를 가지는 TFT가 요구된다. 따라서, 본 연구에서는 차세대 디스플레이에서 요구되는 높은 이동도를 갖는 TFT를 제작하기 위하여, amorphous In-Ga-Zn-O (a-IGZO) 채널하부에 화학적으로 안정하고 전도성이 뛰어난 SnO2 채널을 얇게 형성하여 TFT를 제작하였다. 표준 RCA 세정을 통하여 p-type Si 기판을 세정한 후, 열산화 공정을 거쳐서 두께 100 nm의 SiO2 게이트 절연막을 형성하였다. 본 연구에서 제안된 적층된 채널을 형성하기 위하여 5 nm 두계의 SnO2 층을 RF 스퍼터를 이용하여 증착하였으며, 순차적으로 a-IGZO 층을 65 nm의 두께로 증착하였다. 그 후, 소스/드레인 영역은 e-beam evaporator를 이용하여 Ti와 Al을 각각 5 nm와 120 nm의 두께로 증착하였다. 후속 열처리는 퍼니스로 N2 분위기에서 $600^{\circ}C$의 온도로 30 분 동안 실시하였다. 제작된 소자에 대하여 TFT의 전달 및 출력 특성을 비교한 결과, SnO2 층을 형성한 TFT에서 더 뛰어난 전달 및 출력 특성을 나타내었으며 이동도는 $8.7cm2/V{\cdot}s$에서 $70cm2/V{\cdot}s$로 크게 향상되는 것을 확인하였다. 결과적으로, 채널층 하부에 SnO2 층을 형성하는 방법은 추후 높은 이동도를 요구하는 디스플레이 백플레인 TFT 제작에 적용이 가능할 것으로 기대된다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.277-284
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• 1999

To confirm the food quality of conventionally processed fish extracts, protein quality of boiled crucian carp(Carassius carassius) and bastard halibut(Paralichthys olivaceus) extracts and their residues were evaluated. For the both fish extracts, some of the essential amino acids were lowered significantly but two times more proline and glycine were detected in extracts than those in raw fish meats. Boiling(100oC, 5 hours) caused 1.8(crucian carp)~2.4(bastard halibut) times more total free amino acid contents in fish extracts as compared to those in original fish meats. Taurine, glutamic acid, proline, lysine, and ammonia were the predominant free amino acids released in fish extracts. In vitro digestibility of boiled fish extracts were lower at a level of 4~6% than those of raw fish meats. Fish extraction residue had a higher in vitro digestibility and had a 60% lower level of TI than that of original fish meats. 18(bastard halibut)~ 24%(crucian carp) of available lysine was reduced in boiled fish extracts but a remarkable variation was not noted between extracts and residues. PERs and NPRs of fish extracts were significantly lower than those of casein, while those values of extraction residue were slightly higher as compared to those of control(ANRC casein). In vivo apparent digestibility exhibited a similar trend to in vitro digestibility. Hematological properties in serum of rat fed with fish extracts and residue were not changed significantly but the serum cholesterol concentration were reduced in rats fed fish extraction residue comparing with those of control. These results suggest that body weight loss due to fish extracts may not affect physiological changes.

• Journal of Sensor Science and Technology
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• v.14 no.2
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• pp.96-100
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• 2005

The planar Schottky diodes were fabricated and modeled to probe the device applicability of the cracked GaN epitaxial layer on a (111) silicon substrate. On the unintentionally n-doped GaN grown on silicon, we deposited Ti/Al/Ni/Au as the ohmic metal and Pt as the Schottky metal. The ohmic contact achieved a minimum contact resistivity of $5.51{\times}10.5{\Omega}{\cdot}cm^{2}$ after annealing in an $N_{2}$ ambient at $700^{\circ}C$ for 30 sec. The fabricated Schottky diode exhibited the barrier height of 0.7 eV and the ideality factor was 2.4, which are significantly lower than those parameters of crack free one. But in photoresponse measurement, the diode showed the peak responsivity of 0.097 A/W at 300 nm, the cutoff at 360 nm, and UV/visible rejection ratio of about $10^{2}$. The SPICE(Simulation Program with Integrated Circuit Emphasis) simulation with a proposed model, which was composed with one Pt/GaN diode and three parasitic diodes, showed good agreement with the experiment.

• Current Photovoltaic Research
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• v.7 no.1
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• pp.9-14
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• 2019

Carrier selective solar cell structure has allured curiosity of photovoltaic researchers due to the use of wide band gap transition metal oxide (TMO). Distinctive p/n-type character, broad range of work functions (2 to 7 eV) and risk free fabrication of TMO has evolved new concept of heterojunction intrinsic thin layer (HIT) solar cell employing carrier selective layers such as $MoO_x$, $WO_x$, $V_2O_5$ and $TiO_2$ replacing the doped a-Si layers on either front side or back side. The p/n-doped hydrogenated amorphous silicon (a-Si:H) layers are deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD), which includes the flammable and toxic boron/phosphorous gas precursors. Due to this, carrier selective TMO is gaining popularity as analternative risk-free material in place of conventional a-Si:H. In this work hole selective materials such as $MoO_x$, $WO_x$ and $V_2O_5$has been investigated. Recently $MoO_x$, $WO_x$ & $V_2O_5$ hetero-structures showed conversion efficiency of 22.5%, 12.6% & 15.7% respectively at temperature below $200^{\circ}C$. In this work a concise review on few important aspects of the hole selective material solar cell such as historical developments, device structure, fabrication, factors effecting cell performance and dependency on temperature has been reported.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.54-65
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• 2008

The purpose of this study was to determine the effect of sodium hypochlorite and steam autoclaving on the cyclic fatigue of nickel-titanium endodontic files. Two types of files with a .06 taper and #30 were used, $K3^{(R)}$ (SybronEndo, Glendora, California, USA) and Hero $642^{(R)}$(Micro-Mega, BesanCon, France). The files were divided into 6 experimental groups containing 10 files each group depending the soaking time in 6% sodium hypochlorite solution and number of cycles of steam autoclave. After sterilization, a cyclic fatigue test was performed on each file, and the fracture time was recorded in seconds. The control group underwent the cyclic fatigue test only. After the test, the surface characteristics of the files were observed using scanning electron microscopy (SEM). All groups containing the Hero 64~ files showed a similar cyclic fatigue fracture time. However, the cyclic fatigue fracture time with the $K3^{(R)}$ files was significantly shorter in groups which were treated with sodium hypochlorite than in the control group (P < 0.05), SEM revealed both Hero $642^{(R)}$ and $K3^{(R)}$ files to have significant corrosion on the file surface in groups treated with sodium hypochlorite, compared with the sharp and regular blades of the control group. $K3^{(R)}$ files showed more corrosion than the Hero $642^{(R)}$ files. Bluntness of the blades of the $K3^{(R)}$ file was observed in groups treated with steam autoclave. Although there was no obvious destruction on the surface of steam autoclaved Hero $642^{(R)}$ files, slight bluntness was observed. Sterilizing with a steam autoclave is much less destructive to $K3^{(R)}$ files than sodium hypochlorite. The longer time exposed to sodium hypochlorite, the more destructive pattern was shown on the blades of the files. Therefore, when using sodium hypochlorite solution, the exposure time should be as short as possible in order to prevent corrosion and increase the cyclic fatigue fracture time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.260-267
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• 1995

In temperate zone planting rice at different date subjects the Crop to different climatic condition. The present study aimed at comparison of the change in source-sink relationship of the Japonica(J) and that of IndicaxJaponica(I$\times$J) type rice cultivars caused by shift of heading date. Two J- and two I$\times$J-type cultivars were made to head on August 16, August 26, and September 5. Sink capacity was changed by shift of heading date in different mode between the types of cultivars. In both types major determinant of sink capacity was number of effective tillers, and the number of spikelets per panicle was the minor. In J-type earlier planting/heading was beneficial to increased panicle numbers and this was due mainly to a larger diurnal difference in temperature. I$\times$J-type cultivars favored a higher daily mean temperature to increase the sink capacity. The ability of source at heading, in terms of leaf area per panicle, chlorophyll content per spiklet, photosynthetic ability of leaves per unit area at 25$\^{\circ}C$, carbohydrate and N contents of leaves, was not so different among different heading dates in both types. However, the source activity was governed principally by temperature during grain filling. The J-type cultivars headed on Sept. 5 and I$\times$J-type cultivars headed later than August 16 could not have had sufficient source activity in grain filling due to lower temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.350-359
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• 1993

The effect of gibberellic acid ($GA_3) and abscisic acid (ABA) on KCl-enhanced proteolysis of senescing leaves of rice(Oryza sativa L. cv. Chilsung) was studied. Emphasis was given to their effects on KCI-enhanced efflux of amino acids and proteinase activity. When treated singly, $GA_3 affected leaf proteolysis little, while ABA increased proteolysis, the rate of amino acid efflux, and ribulose -1,5 -bisphosphate carboxylase / oxygenase (Rubisco)-degrading endoproteinase activity. An additive increase in all three parameters mentioned above was observed when leaves were treated with ABA and KCl. No such an additive effect was found when $GA_3 was treated with KCl. Both $GA_3 and ABA helped to alleviate the KCI-suppressed activity of Rubisco-degrading exoproteinases. The additive increase in proteolysis of rice leaves in the presence of both ABA and KCl could thus be ascribed to a further increase in the efflux of protein hydrolyzates and Rubisco-degrading endoproteinase activity. An increase in proteolysis was accompanied by a decrease in water absorption, and the combined treatment of ABA with KCl resulted in a further reduction of water absorption.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.217-226
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• 2004

This study was canied out to evaluate the quality characteristics of the fermented pork with Korean traditional seasonings. The samples, outside muscle of pork ham were cut to cube(7 ${\times}$ 12 ${\times}$ 2cm) and five Korean traditional seasonings such as garlic paste(TI), pickled Kimchi(T2), pickled Kimchi juice(T3), soybean paste(T4), red pepper paste(T5) were seasoned by the proportions of meat to seasonings(1 : 1). The seasoned samples were fennented at - 1 ${\pm}$ 1$^{\circ}C$ for 20 days. According to proximate composition analysis, all pork samples contained protein 20 ${\sim}$ 22%, fat 3 ${\sim}$ 5%, moisture 64 ${\sim}$ 70% and ash 1.8 ${\sim}$ 2.0%. However, T5 had high crude fat level and relatively low moisture content. The highest pH among treatments was shown in TI whereas T3 showed the lowest. Water holding capacity(WHC) of T4 and T5 were higher, while those values were lower in T3 compared with other treatment. Shear force value was the highest in T5, while it was the lowest in T4. TBARS value of T3 was the highest, while that was the lowest in T4. Moreover the highest VBN value was observed in T4 due to fermentation of soy protein. However, the lowest VBN value shown in Tl indicated the inhibition of protein degradation by the garlic. The highest saccarinity was shown in T5 but it was the lowest of in T3. Salinity was shown to be high in T2 and low in T5. $L^*$ values of T4 was higher both at the surface and inner side of samples than the others but T5 showed the lowest value. T2 showed the highest $a^*$ value but T4 and T5 showed the lowest. In the result of sensory evaluation for cooked meat, T5 had the highest score in all item including overall acceptability, while T4 had the lowest score. Unsaturated fatty acid(UFA) ratio of T5 and n were 72.16 and 69.93 respectively, and the ratio of UFA/Saturated fatty acid(SFA) were higher in the order of T5 >T4> T3 >Tl >T2. Overall quality characteristics were higher in the order of T5 >T2 >Tl >T4 >T3.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.45-55
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• 1986

This paper aims to study the reactions of lipid or oxidized lipid with protein during drying and storing hair tail fish(Trichurus lepturus) and flounder(Kanakius kitaharai) being generally consumed as dried seafood products in Korea and their influence on the drop of in vitro protein digestibility of these fish meat. The results of the study are as follows: The digestibility of the raw materials of flounder and hair tail fish was 87.63% and 86.08% respectively, and that of sundried and hot air dried materials went down $1{\sim}2$ percent with drying process. But in case of defatted and sundried materials, the rate increased 85.15% and 87.15% respectivley. After 30 days of storage, the digestibility decreased in all materials, and hot air dried meat showed a significant decrease. Trypsin indigestible substrate (TIS) contents of flounder and hair tail fish, in case of raw materials were 0.88 and 0.96mg/g. solid repectiveiy and in case of defatted and sundried materials, TIS contents showed a low increase and digestibility showed a high increase. Brown pigment formation had a wide range of increase in case of the sundried and hot air dried materials and it was increased with duration of storage and temperature. The major fatty acids in the fats of hair tail fish and flounder were $C_{18:1},\;C_{16:0},\;C_{22:6}\;and\;C_{16:1}$ and rate of unsaturated to saturated fatty acids was 79.2:20.8 for flounder, 67.8:32.2 for hair tail fish. After 30 days of storage at room temperature. saturated fatty acids increased compared with the raw materials while unsaturated fatty acids showed a tendency to decrease. Avaialble lysine of hair tail fish was higher than that of flounder and both of them lost about 8.23% of that in raw materials after 30 days of storage.