• 대한치과보철학회지
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• 제39권4호
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• pp.336-350
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• 2001

The purpose of this study was to investigate corrosion tendency and to compare corrosion resistance of three dental magnetic attachments and its keeper alloy by coercive, electrochemical method. By using petentiodynamic polarization technique, magnetic elements and its keeper alloy of Magfit EX600 system(MF, MFK), Dyna ES regular system(DN, DNK) and Shiner SR magnet system(SR, SRK) were corroded electrochemically in 0.9% NaCl electrolytic solution. Open-circuit potential and anodic polarization curve was measured with Potentiostat(model 273 EG&E) and polarization curve was created by current density per square area following scanning of increased series of voltage in the rate of 1.0mV per second. Before and after electrochemical corrosion, the surface roughness test was done. Thereafter the change of mean surface roughness value(Ra) and mean peak value(Rt) of surface roughness was compared one another. In order to observe the corroded surface of each specimen, metallurgical light microscopic(${\times}37.5$) and scanning electron microscopic view(SEM ${\times}100$) was taken and compared one another. Conclusion is followings. 1. All of six covering metal of dental magnetic attachments and its keeper alloy were corroded in various degree after electrochemical corrosion. 2. The corrosion resistance of which used in this experiment is the following in high order; DNK, MFK, DN, MF, SRK and SR. 3. Especially Shiner magnet system and its keeper alloy were more severely corroded after electrochemical corrosion and the change of Ra Rt value were more increased than others. 4 Metallurgical and scanning electron microscopic view showed the pitting corrosion tendency of all experimental alloy but DNK and SR. 5. Covering metal of magnet was more corroded than its keeper alloy.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.306-308
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• 2007

Poly(ethylene glycol) dimethyl ether (PEGDME)/fumed silica/ 1-methyl -3-propylimidazolium iodide (MPII)/$I_2$ mixtures were used as polymer electrolytes in solid state dye-sensitized solar cells (DSSCs). The contents of MPII were changed and the concentration of $I_2$ was fixed at 0.1 mole% with respect to the MPII. The maximum ionic conductivity was obtained at [EG]:[MPII]:[$I_2$]=10:1.5:0.15. It was supposed that the maximum of ionic conductivities would match with that of cell efficiencies, if the ionic conductivity is a rate determining step in the sol id state DSSCs. However, the maximum composition did not show the maximum solar cell performance, indicating the mismatch between ionic conductivity and cell performance. This suggests that the ionic conductivity may not be the rate controlling step in determining the cell efficiency in these experimental conditions, whereas other parameters such as the electron recombination might play an important role. Thus, we tried to modify the surface of the $TiO_2$ particles by coating a thin metal oxide such as $Al_2O_3$ or $Nb_2O_5$ layer to prevent electron recombination. As a result, the maximum of the cell efficiency was shifted to that of the ionic conductivity. The peak shifts were also attempted to be explained by the diffusion coefficient and the lifetime of electrons in the $TiO_2$ layer.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2399-2403
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• 2012

Objective: To compare expression level of serum tumor associated materials (TAM) with several conventional serum tumor biomarkers, eg., carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA19-9), carbohydrate antigen 15-3 (CA15-3), alpha-fetoprotein(AFP), in selected solid tumors. Methods: Patients diagnosed histologically or cytologically with liver, breast, esophageal, gastric, colorectal or pancreatic cancers were enrolled into this study. After diagnosis, the level of TAM was determined by chemical colorimetry, and levels of conventional tumor markers was measured by chemiluminescence methods. Results: A total of 560 patients were enrolled into this study. No statistically significant difference was detected in TAM and the above mentioned tumor biomarkers in terms of their positivity and negativity ( P>0. 05). Conclusions: Detection of TAM in liver, breast, esophageal, gastric, colorectal, and pancreatic cancer patients demonstrates a good accordance with CEA, CA199, CA153, and AFP, thus suggesting that further study is warranted to verify whether TAM could be a surrogate for these conventional biomarkers.

• 에너지공학
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• 제19권4호
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• pp.234-239
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• 2010

원형 파이프를 유동하는 6.5% EG 수용액으로부터 만들어진 아이스슬러리의 열전달 특성을 분석하기 위한 실험을 수행하였다. 실험 장치의 시험부는 13.84 mm 내경과 1,500 mm의 길이를 가진 동관으로 제작되었다. 아이스슬러리는 시험부 주변에 이중관 형태로 만들어진 원형관 내부를 유동하는 온수에 의해 가열되었다. 본 연구의 실험에 적용된 IPF와 질량 유속은 각각 0 ~ 25% 그리고 1000 ~ 3,000 kg/$m^2s$의 범위이었고, 온수의 온도와 유량은 일정하게 유지하였다. 측정된 열전달량은 질량 유량과 IPF가 증가함에 따라 증가하였으나, IPF의 영향은 높은 질량 유량에서는 작은 것으로 나타났다. 낮은 질량유량에서는 열전달 계수의 급격한 상승이 15 ~ 20%의 IPF에서 나타났다. 마지막으로 측정된 열전달계수는 기존의 열전달상관식들에 의해 계산된 열전달계수와 비교하여 제시하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.299-299
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• 2013

Indium Tin Oxide (ITO) has widely been used as a transparent conductive oxide (TCE) for photovoltaic devices. Lately, flexibility of ITO becomes an issue as demand of flexible device increases. Several scientists have tried to substitute ITO to different materials such as conductive polymer, graphene, CNT, and metal nanowire because of ITO brittleness. Among the substitute materials, PEDOT:PSS has mostly paid attention because PEDOT:PSS has excellent flexibility and good conductivity. The conductivity of PEDOT:PSS increases up to 1000 S/cm with additives such as DMSO, EG, sorbitol, and so on. In our research group, we introduce a conductive polymer PEDOT:PSS as a buffer layer to improve not only flexibility but also conductivity. As PEDOT:PSS layer forms beneath ITO thin film (20 nm), sheet resistance decreases from $230{\Omega}$/${\Box}$ to $85{\Omega}$/${\Box}$ and crack initiation decreases from 4.5 mm to 3.5 mm as well. We have fabricated organic photovoltaic device and power conversion efficiencies using conventional ITO electrode and ITO/PEDOT:PSS hybrid electrode. The photovoltaic property such as power conversion efficiency for ITO/PEDOT:PSS hybrid electrode is comparable to the value obtained using conventional ITO electrode on glass substrate.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.75-79
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• 1996

The purpose of this study was to investigate the effect of vitamin {TEX}$B_{6}${/TEX} deficiency on the utilization and recuperation of stored fuel in exercising rats. Thirty six rats were fed either a vitamin {TEX}$B_{6}${/TEX} deficient diet(-{TEX}$B_{6}${/TEX}) or a control diet(+{TEX}$B_{6}${/TEX}) for 5 weeks, then subdivided into 3 group: non-exercise group(NE), exercise group(EX), exercise and recuperation group(EX). EX group were exercised in treadmill({TEX}$10^{o}${/TEX}, 0.5~0.8km/h)for 2 hours and ER group were recuperated three days with the respective diet after exercise. Glucose(GLU), glycogen(GLY), protein(PRO), trigyceride(TG) and free fatty acid(FFA) were compared in plasma(P), liver(L) and skeletal muscle(M) of rats. Compared to +{TEX}$B_{6}${/TEX} rats, in NE group, the level of L-GLY of -{TEX}$B_{6}${/TEX} rats was higher, M-TG, L-PRO of -{TEX}$B_{6}${/TEX} rats were lower and there were no differences in P-PRO, P-FFA, P-TG, M-GLY, M-PRO and L-TG. In EX group, the levels of P-FFA, L-PRO of -{TEX}$B_{6}${/TEX} rats were higher. P-TG, L-TG of -{TEX}$B_{6}${/TEX} rats were lower and there was no difference in L-GLY. In EG group, the levels of P-GLU, P-PRO, P-RG, L-PRO of -{TEX}$B_{6}${/TEX} rats were lower and there were no differences in L-GLY, L-TG, M-TG and M-GLY. these results suggest that a lowered intake of vitamin {TEX}$B_{6}${/TEX} may impair the recuperation of aminals after exercise related to exercise fuel stores although there is a compensation among stored fuel utilization during exercise.

• 정보보호학회논문지
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• 제31권5호
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• pp.1083-1095
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• 2021

최근 사용자의 인터넷 의존성 증가와 각종 IT 디바이스의 보급과 확산에 따라, 과거에 비하여 개인 생활 전반에 정보보호가 미치는 영향력이 확대되었다. 이와 더불어 보안을 위협하는 침해 요인들이 지속적으로 복잡, 다양해지고 가짜뉴스 확산, 온라인 신분 도용, 사이버 불링 등을 비롯한 개인의 안전한 온라인 환경을 위협하는 요소들이 사회적으로 증가함에 따라, 정보보호 전문 인력 양성의 필요성이 증가하고 있다. 나아가 기업의 정보보호 업무 종사자 이외에 사회의 모든 구성원이 정보보안의 위협에서 자유로울 수 없게 됨에 따라, 개인의 정보보호에 대한 인식 제고와 자발적인 정보보호 행동을 유도하기 위한 다양한 정보보호 교육 과정의 마련이 필요하다. 따라서, 본 연구에서는 현재 이루어지고 있는 국내·외 정보보호 교육 과정의 현황과 특징에 대하여 분석한다. 이를 통하여 정보보호 교육 필요성과 교육 체계 수립의 전략을 모색하여 본 연구에서는 국내 환경에 적용 가능한 정보보호 교육 표준 프레임워크를 제시하고자 한다. 이는 개인의 정보보호 인식과 지식 수준을 제고하여 국내 정보보호 전문 인력 양성과 더불어 개인과 조직, 사회 전반의 정보보안 수준을 향상시켜 국가 경쟁력 향상에 기여할 것으로 판단된다.

• 대한방사성의약품학회지
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• 제5권1호
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• pp.11-17
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• 2019

Recently, antibody-like scaffold proteins have received a great deal of interest in diagnosis and therapy applications because of their intrinsic features that are often required for tumor imaging and therapy. Intrinsic issues that are associated with therapeutic application of antibody-like scaffold proteins, particularly in cancer treatment, include an efficient and straightforward radiolabeling for understanding in vivo biodistribution and excretion route, and monitoring therapeutic responses. Herein, we report an efficient and straightforward method for radiolabeling of antibody-like scaffold proteins with the $[^{99m}Tc(OH_2)_3(CO)_3]^+$ ($^{99m}Tc$-tricarbonyl) by using a site-specific direct labeling method via hexahistidine-tag, which is a widely used for general purification of recombinant proteins with His-affinity chromatography. Repebody is a new class of antibody-like scaffold protein that consists of highly diverse leucine-rich repeat (LRR) modules. Although all possible biomedical applications with repebody are ongoing, it's in vivo biodistribution and excretion pathway has not yet been explored. In this study, hexahistidine ($His_6$)-tag bearing repebody (rEgH9) was labeled with [$^{99m}Tc$]-tricarbonyl. Repebody protein was radiolabeled with high radiolabeling efficiency (>90%) and radiolabeled compound was more than 99% pure after purification. These results clearly demonstrate that the present radiolabeling method will be useful molecular imaging study.

• 한국식생활문화학회지
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• 제36권5호
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• pp.430-440
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• 2021

The purpose of this study was to provide basic data for future research and suggest product development and market segmentation strategies by identifying the perceptions and consumption behaviors of vegetarians in each segment of the vegetarian market. According to food consumption value, a total of three market segments were derived, and the markets were named based on their characteristics, including 'environment and animal protection', 'multiple consideration' and 'low interest'. As a result of analyzing the perception of vegetarian-based food, "environment and animal protection" and "multiple consideration" presented positive perceptions of a vegetarian food product. Conversely, the group stating low interest expressed negative perceptions of the vegetarian food product. An analysis of the requirements for development for vegetarian-based foods products (eg. aquafaba), indicated that the development requirements for all products, except cultured and processed meats, were high.?Considerable demand was observed for vegetarian menus and vegetarian restaurants. As a result of the analysis on the necessity of the elements of the vegetarian restaurant menu, the subjects that stated "multiple consideration" had significantly higher awareness of issues related to vegetarian foods than others.

• 한국축산시설환경학회지
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• 제13권1호
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• pp.45-52
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• 2007

본 연구는 불가사리의 사료적 가치를 평가하기 위하여 불가사리 추출물의 항균효과, 영양소, 아미노산 조성 및 산란계에서 영양소 이용을 측정하였다. 불가사리 추출물은 열수추출법과 에테르추출법으로 추출하여 항균효과 측정에 이용하였다. 불가사리의 사료적 가치평가는 $60^{\circ}C$에서 3일간 건조하여 분쇄(Grinding starfish, GS) 및 extrusion 가공 (Extruded grinding starfish, EGS), 효소첨가발효(Enzyme fermented starfish, EFS) 및 효소미첨가 발효(Non-enzyme fermented starfish, NEFS)의 4개 sample에 대하여 영양성분 및 소화율을 측정하였다. 실험 결과, 불가사리 추출물 항균실험은 열수와 에테르추출물로 나누어 유산균과 병원성미생물에 대한 성장 및 억제실험을 실행 하였는데 항균효과가 낮게 나타났다. 불가사리의 사료적 가치 평가를 위하여 불가사리 가공방법에 따른 단백질 함량은 GS와 EGS에 비하여 EFS와 NEFS가 각각 62.86%와 52.82%로 유의적(p<0.05)으로 높았다. Ca 함량은 GS 및 EGS가 각각 17.26%와 18.26%로 EFS와 NEFS의 5.37%와 8.55%에 비하여 높았지만 그 원인은 EFS 및 NEFS는 발효 후 Ca을 제거하였기 때문으로 사료되었다. 불가사리의 가공방법에 따른 총아미노산 함량은 GS, EGS, EFS, NEFS에서 각각 17.17mg/g, 20.28mg/g, 36.30mg/g 및 29.96mg/g 으로 나타났다. 이 전체 아미노산 함량을 단백질 함량에 대한 비율(Total amino acid/CP, TC ratio)로 환산하면 GS, EGS, EFS, NEFS에서 각각 45.5%, 47.5%, 57.7% 및 56.7%로서 발효 처리시 전체 아미노산 함량이 높게 나타났다. 단백질 소화율은 발효 처리한 불가사리(EFS와 NEFS)에서 약 80%이었으며, Ca의 이용율도 80%를 상회하였다. 효소 처리한 EFS를 산란계에 급여시 영양소 이용율은 다른 처리구에 비하여 현저하게 높게 나타났다. 본 실험의 결과 적절하게 가공한 불가사리는 사료자원으로서 가치가 높게 평가되었다.