• 한국정보전자통신기술학회논문지
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• 제2권1호
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• pp.3-9
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• 2009

AMOLED 디스플레이는 LCD에 비해 넓은 시야각, 빠른 응답 속도, 박막화의 용이성 등의 많은 장점들을 갖고 있으나 불균일한 TFT의 전기적 특성과 전원선의 전압 강하에 의한 휘도 불균일, 잔상 현상 및 수명 등과 같은 많은 문제점들이 있다. 이 중에서 본 논문에서는 구동 TFT 소자의 hysteresis 현상에 의해 발생하는 가역적 잔상 현상을 개선하고자 한다. TFT의 hysteresis 특성을 개선하기 위해 게이트 산화막 증착 전에 표면 처리 조건을 변경하였다. 게이트 산화막 증착 전에 실시한 자외선 및 수소 플라즈마 표면 처리는 게이트 산화막과 다결정 실리콘 박막 사이의 계면 trap 밀도를 $3.11{\times}10^{11}cm^{-2}$로 감소시켰고, hysteresis 레벨을 0.23 V로 줄였으며 출력 전류 변화율을 3.65 %로 감소시켰다. 자외선 및 수소 플라즈마 처리를 행함으로써 AMOLED 디스플레이의 가역적 잔상을 많이 개선할 수 있을 것으로 기대된다.

• 복식
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• 제65권6호
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• pp.25-35
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• 2015

The purpose of this study is to investigate the characteristics of members and communities that have significant influence in the online fashion community through their word-of-mouth activities. In order to identify the influence and the diffusion of word-of-mouth in fashion community, the study selected one online fashion community. Then, the study sorted the online posts and comments made on fashion information and put them into the matrix form to perform social network analysis. The result of the analysis is as follows: First, the fashion community network used in the study has many active members that relay information very quickly. Average time for information diffusion is very short, taking only one or two days in most cases. Second, the influence of word-of-mouth is led by key information produced from only a few members. The number of influential members account for less than 20% of the total number of community members, which indicate high level of degree centrality. The diffusion of word-of-mouth is led by even fewer members, which represent high level of betweenness centrality, compared to the case of degree centrality. Third, component characteristic shares similar information with about 70% of all members being linked to maximize information influence and diffusion. Fourth, a node with high degree centrality and betweenness centrality shares similar interests, presenting strain effect to particular information. Specially, members with high betweenness centrality show similar interests with members of high degree centrality. The members with high betweenness centrality also help expansion of related information by actively commenting on posts. The result of this research emphasizes the necessity of creation and management of network to efficiently convey fashion information by identifying key members with high level of information influence and diffusion to enhance the outcome of online word-of-mouth.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권6호
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• pp.235-240
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• 2003

In this paper, we present the fabrication and the characteristic analysis of sequential lateral solidification(SLS) poly-Si thin film transistors(TFT's) with molybdenum gate for active matrix liquid displays (AMLCD's) pixel controlling devices. The molybdenum gate is applied for the purpose of low temperature processing. The maximum processing temperature is 55$0^{\circ}C$ at the dopant thermal annealing step. The SLS processed poly-Si film which is reduced grain and grain boundary effect, is applied for the purpose of electrical characteristics improvements of poly-Si TFT's. The fabricated low temperature SLS poly-Si TFT's had a varying the channel length and width from 10${\mu}{\textrm}{m}$ to 2${\mu}{\textrm}{m}$. And to analyze these devices, extract electrical characteristic parameters (field effect mobility, threshold voltage, subthreshold slope, on off current etc) from current-voltage transfer characteristics curve. The extract electrical characteristic of fabricated low temperature SLS poly-Si TFT's showed the mobility of 100~400cm$^2$/Vs, the off current of about 100pA, and the on/off current ratio of about $10^7$. Also, we observed that the change of grain boundary according to varying channel length is dominant for the change of electrical characteristics more than the change of grain boundary according to varying channel width. Hereby, we comprehend well the characteristics of SLS processed poly-Si TFT's witch is recrystallized to channel length direction.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권3호
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• pp.500-514
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• 1996

The purpose of this study was to observe the tissue response in applying staples and various suture materials to both scalp and buccal mucosa in rabbits. 18 rabbits were divided into 6 groups. The incised wounds of both scalp and buccal mucosa were sutured with staples, polyglactin 910, chromic catgut, mer silk and nylon. The experimental animals were sacrificed after 1, 3, 5, 7, 10, 14 days posto peratively 3 animals at one time. The tissue was stained with Hematoxylin and eosin, and Masson's Trichrom. In light microscopic examinations, the sutured sites were examined histologi cally according to 6 degrees about inflammation and collagen deposit. The results were obtained as follows, 1. The chromic catgut, an absorbable suture material, was absorbed by 7 days, whereas polyglactin 910 and mersilk began to get absorbed after 7 days. 2. Mersilk manifested a broad range of inflammation in the scalp, and both staple and nylon showed a severe inflammatory reaction in the buccal mucosa. 3. With polyglactin 910, both tissue samples showed only minor foreign body reaction, however in the scalp, the process of fibrosis took place compara tively slowly, whereas in the buccal mucosa, it occurred promptly and manifested active fibrosis by 7 days. 4. Mersilk showed widespread a matrix formation in both scalp and buccal mucosa, and showed the most severe inflammatory reaction by 3 days, which did not seem to decrease even after 7 days. 5. Both staple and nylon showed relatively a severe inflammatory reaction, however fibrosis took place rather promptly compared to the other groups. 6. Generally, in the buccal mucosa fibrosis occurred more promptly than in the scalp in both control and experimental groups. 7. Retention of the suture material and stability of the knot were the best with the staple, and better stability was manifested by the multi-stranded poly glactin 910 and mersilk than singlestranded chromic catgut and nylon. From above results, in the buccal mucosa absorbable suture materials especially polyglactin 910 showed better response in the aspect of inflammatory reaction, while in the scalp monofilament suture materials such as staple and nylon manifested a early fibrosis and collagen formation.

• 대한전자공학회논문지SP
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• 제44권4호통권316호
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• pp.86-92
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• 2007

2D 영상의 특징점을 추적하는 이산동적 모델을 고안한다. 종래의 스네이크 접근은 내외 추진력으로 구성된 에너지함수를 최소화하도록 구획을 변형시켜가면서 영상 내의 원하는 특징에 밀착시켜간다. 이 때 스네이크화소를 중심한 인접화소군은 사각형 같은 평면 2차 행렬이다. 본 논문에서는 유사 특성점들을 상호 연결하는 모델 구조를 제시한다. 에너지모델은 그 국부최소점이 활성처리에 유용한 교차 해법에 적합하도록 설계한다. 추적시 선 형태의 1차 행렬 블록을 사용한다. 진행 방향의 반대 끝 라인으로부터 굴곡상태를 만족하는 시발점들을 선정하고 에너지 최소처리를 통해 이웃 라인으로 순차 자동 이동한다. 추적 경로는 상승 하강점 또는 극대 극소점과 같은 굴곡 한계에 의존한다. 이와 같은 층위적 접근은 인접데이터 라인 사이에 수직 또는 수평 방향으로 높은 상관성을 갖는 일방향 특성이 있는 디지털 영상의 특징점 추적에 유용하다. 그리고 인체 경동맥초음파영상에서 그 내 외막 시점을 추적하는 실험으로 알고리즘의 효과를 확인하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권4호
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• pp.1603-1623
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• 2020

Multiple Mobile Robots System (MMRS) has shown many attractive features in lots of real-world applications that motivate their rapid and wide diffusion. In MMRS, the Cooperative Localization (CL) is the basis and premise of its high-performance task. However, the statistical characteristics of the system noise should be already known in traditional CL algorithms, which is difficult to satisfy in actual MMRS because of the numerous of disturbances form the complex external environment. So the CL accuracy will be reduced. To solve this problem, an improved Adaptive Active Cooperative Localization (A²CL) algorithm based on information optimization strategy for MMRS is proposed in this manuscript. In this manuscript, an adaptive information fusion algorithm based on the variance component estimation under Extended Kalman filter (VCEKF) method for MMRS is introduced firstly to enhance the robustness and accuracy of information fusion by estimating the covariance matrix of the system noise or observation noise in real time. Besides, to decrease the effect of observation uncertainty on CL accuracy further, an observation optimization strategy based on information theory, the Model Predictive Control (MPC) strategy, is used here to maximize the information amount from observations. And semi-physical simulation experiments were carried out to verity the A²CL algorithm's performance finally. Results proved that the presented A²CL algorithm based on information optimization strategy for MMRS cannot only enhance the CL accuracy effectively but also have good robustness.

• BMB Reports
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• 제37권3호
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• pp.298-303
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• 2004

In general, a SYPRO Ruby dye is well known as a sensitive fluorescence-based method for detecting proteins by one-or two-dimensional SDS-PAGE (1-DE or 2-DE). Based on the SYPRO Ruby dye system, the combined two-dimensional fibrin zymography (2-D FZ) with SYPRO Ruby staining was newly developed to identify the Bacillus sp. proteases. Namely, complex protein mixtures from Bacillus sp. DJ-4, which were screened from Doen-Jang (Korean traditional fermented food), showed activity on the zymogram gel. The gel spots on the SYPRO Ruby gel, which corresponded to the active spots showing on the 2-D FZ gel, were analyzed by a matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometric analysis. Five intracellular fibrinolytic enzymes of Bacillus sp. DJ-4 were detected through 2-D FZ. The gel spots on the SYPRO Ruby dye stained 2-D gel corresponding to 2-D FZ were then analyzed by MALID TOF MS. Three of the five gel spots proved to be quite similar to the ATP-dependent protease, extracellular neutral metalloprotease, and protease of Bacillus subtilis. Also, the extracellular proteases of Bacillus sp. DJ-4 employing this combined system were identified on three gels (e.g., casein, fibrin, and gelatin) and the proteolytic maps were established. This combined system of 2-D zymography and SYPRO Ruby dye should be useful for searching the specific protease from complex protein mixtures of many other sources (e.g., yeast and cancer cell lines).

• Nutrition Research and Practice
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• 제8권5호
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• pp.521-525
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• 2014

BACKGROUND/OBJECTIVES: Artemisinin (AT), an active compound in Arternisia annua, is well known as an anti-malaria drug. It is also known to have several effects including anti-oxidant, anti-inflammation, and anti-cancer activities. To date, the effect of AT on vascular disorders has not been studied. In this study, we investigated the effects of AT on the migration and proliferation of vascular smooth muscle cells (VSMC) stimulated by platelet-derived growth factor BB (PDGF-BB). MATERIALS/METHODS: Aortic smooth muscle cells were isolated from Sprague-Dawley rats. PDGF-BB stimulated VSMC migration was measured by the scratch wound healing assay and the Boyden chamber assay. Cell viability was determined by using an EZ-Cytox Cell Viability Assay Kit. The production of reactive oxygen species (ROS) in PDGF-BB stimulated VSMC was measured through $H_2DCF$-DA staining. We also determined the expression levels of signal proteins relevant to ROS, including measures of extracellular signal-regulated kinase (ERK) 1/2 measured by western blot analysis and matrix metalloproteinase (MMP) 9 measured by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: AT ($10{\mu}M$ and $30{\mu}M$) significantly reduced the proliferation and migration of PDGF-BB stimulated VSMC in a dose-dependent manner. The production of ROS, normally induced by PDGF-BB, is reduced by treatment with AT at both concentrations. PDGF-BB stimulated VSMC treated with AT ($10{\mu}M$ and $30{\mu}M$) have reduced phosphorylation of ERK1/2 and inhibited MMP9 expression compared to untreated PDGF-BB stimulated VSMC. CONCLUSIONS: We suggest, based on these results, that AT may exert an anti-atherosclerotic effect on PDGF-BB stimulated VSMCs by inhibiting their proliferation and migration through down-regulation of ERK1/2 and MMP9 phosphorylation.

• Journal of Microbiology and Biotechnology
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• 제26권10호
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• pp.1781-1789
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• 2016

Glargine insulin is a long-acting insulin analog that helps blood glucose maintenance in patients with diabetes. We constructed the pPT-GI vector to express prepeptide glargine insulin when transformed into Escherichia coli JM109. The transformed E. coli cells were cultured by fed-batch fermentation. The final dry cell mass was 18 g/l. The prepeptide glargine insulin was 38.52% of the total protein. It was expressed as an inclusion body and then refolded to recover the biological activity. To convert the prepeptide into glargine insulin, citraconylation and trypsin cleavage were performed. Using citraconylation, the yield of enzymatic conversion for glargine insulin increased by 3.2-fold compared with that without citraconylation. After the enzyme reaction, active glargine insulin was purified by two types of chromatography (ion-exchange chromatography and reverse-phase chromatography). We obtained recombinant human glargine insulin at 98.11% purity and verified that it is equal to the standard of human glargine insulin, based on High-performance liquid chromatography analysis and Matrix-assisted laser desorption/ionization Time-of-Flight Mass Spectrometry. We thus established a production process for high-purity recombinant human glargine insulin and a method to block Arg (B31)-insulin formation. This established process for recombinant human glargine insulin may be a model process for the production of other human insulin analogs.

• Applied Microscopy
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• 제3권1호
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• pp.29-38
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• 1973

Introduction. The human cutaneous scars manifest themselves many ways in different types according to the factors such as the age, sex, race of the patient as well as the location,. kind and heal ing process of the wound. Among the scars it is quiet difficult to verify the clinical course of the hypertrophic or keloidal scars from the true keloids. However, clinical observations indicate that stress, either mechanical or in the forms of chronic infections, can induce a functional change in the fibroblasts causing an excessive production of collagenous matrix. In this study, we preliminary attempt to justify any difference of the cellular structure between keloids and hypertrophic scars by using electron microscope. Material and Methods. A total of 23 cases: 2 scars, 2 hypertrophic scars and 19 keloids are examined. Immediately, the biopsy tissue was fixed in 10% neutral formalin and 4% glutaraldehyde solution in phosphate buffer for 4 hours, post fixed in 1 % osmium tetraoxide for two hours, dehydrated with graded alcohol, and embedded in Epon 812. Thick sections were stained with hematoxylin eosin, periodic acid-Schiff(PAS) and Van Gieson stain. Thin sections were cut and uranyle acetate, lead citratestain and examined with the electron microscope. Result. The morphologic features of keloid showed thick, homogenously eosinophilic bands of collagen and numberous large active fibroblasts. The hypertrophic scar and soft scar are more cellular than keloid and composed thinner collagenous fiber. For this paper in the etiology of keloids can not as be defined, but and interesting keloidal tissue fibroblast showed irregular nucleus with irregular shape dense bodies and fibril materials contained in to the cytoplasm.