• Title/Summary/Keyword: Barrier factor

검색결과 446건 처리시간 0.02초

VOD 스트리밍 데이터를 위한 Consistency 알고리즘 설계 (Design of a Consistency Algorithm for VOD Streaming Data)

  • 장승주
    • 한국정보통신학회논문지
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    • 제10권8호
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    • pp.1414-1421
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    • 2006
  • 본 논문에서는 VOD에서 스트리밍 데이터를 효율적으로 서비스할 수 있는 Consistency 알고리즘을 제시한다. 미디어 데이터 서비스를 위해 우선 하나의 미디어 데이터를 라운드 로빈 방식으로 스트라이핑하여 각 호스트의 저장 노드에 저장한다. 본 논문에서는 일반적인 계산 용도로 사용되는 barrier 메커니즘을 미디어 플레이 최소 단위인 (SH, GOP) 미디어 데이터에 서비스할 수 있도록 제시하였다. 데이타 처리 방식은 하나의 호스트에 한 프래그먼트 크기의 공유메모리를 할당한다. 이 공유메모리 는 barrier 메커니즘을 통하여 RTP패킷 전송 단위로 결정될 프래그먼트 데이터의 조합을 형성한다. 본 논문에서 제시한 알고리즘에 대해서 실험을 수행하기 위해서 VOD 시스템에서 프로그램을 작성하였다.

PVC 및 알루미늄을 진공 접착한 방근시트와 E.P시트 및 도막방수층을 부분 절연한 방수/방근 복합공법의 옥상녹화 적용성 평가에 관한 실험적 연구 (Test and Field Application Analysis for Root Barrier using Aluminum Film Adhered to PVC and Waterproofing using E.P Sheet with Asphalt Membrane for Green Roof System)

  • 오상근;권시원;박진상;박상찬
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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    • pp.71-74
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    • 2006
  • The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. In this paper I focused to assure the basic system for waterproofing materials and root barrier apply to green roof as searching the application of field condition. And I suggest proper waterproofing and root barrier as considering the mutual connection and plant growth. and it can be a standard model to adopt to domestic green roof system.

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SiC 다이오드를 이용한 전력변환회로 (Power Conversion Circuits using SiC Schottky Barrier Diode)

  • 이유신;오덕진;김희준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.192-195
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    • 2001
  • In this report, we firstly have investigated the electrical characteristics of silicon carbide (SiC) schottky barrier diode and compared the characteristics to those of conventional Si diode through simulation and experiment. Secondly we have investigated the influence of two kinds of diodes to the power conversion circuit of the systems. From the investigation results it is verified that SiC schottky barrier diode is more superior to Si diode in thermal and reverse recovery, characteristics, which are the important factors in the size reduction and higher reliability of the systems. Finally though the experiment applied to PFC(Power Factor Correction) circuits, we precisely verified excellency to thermal characteristic of SiC schottky barrier diode any other diode.

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장애인 및 노약자를 위한 생활관련 시설의 연계방향 (A Suggestion Connecting Living Facilities for the Disabled and the Elderly)

  • 강병근;성기창;박광재;윤영삼;김상운;정현정;류상오
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제15권1호
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    • pp.33-40
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    • 2009
  • This study aims to plan connecting living facilities considering on the Barrier Free Walking of the disabled and the elderly in the residential area. We had found several physical problems on the pedestrian's way that becomes the major factor of disturbing the barrier free movement for using living facilities in the local area by investigations and enquetes. We had suggested the arrangement method for these physical problems on the pedestrian's way and building the ideal area for living facilities by the disposition stages with the result of investigations and enquetes. After these process, we had planned connecting living facilities considering on the Barrier Free Walking of the disabled and the elderly in the residential area.

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고온, 고전압 Ni/4H-SiC 및 Ni/6H-SiC Schottky 다이오드의 제작 및 전기적 특성 연구 (Fabrications and Characterization of High Temperature, High Voltage Ni/6H-SiC and Ni/4H-SiC Schottky Barrier Diodes)

  • 이호승;이상욱;신동혁;박현창;정웅
    • 전자공학회논문지D
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    • 제35D권11호
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    • pp.70-77
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    • 1998
  • 본 논문에서는 nickel/silicon carbide(Ni/SiC) 접합에 의한 Schottky 다이오드를 제작하고, 그 전기적 특성을 조사하였다. Ni/4H-SiC의 경우, 산화막 모서리 단락을 하였을 때 상온에서 973V의 역방향 항복전압이 측정되었으며 이는 모서리 단락되지 않은 Schottky 다이오드의 역방향 항복전압 430V에 비해 매우 높았다. Ni/6H-SiC Schottky 다이오드의 경우, 산화막으로 모서리 단락시켰을 때와 시키지 않았을 때의 역방향 항복전압은 각각, 920V와 160V 였다. 고온에서의 소자 특성도 매우 좋아서 Ni/4H-SiC Schottky 다이오드와 Ni/6H-SiC Schottky 다이오드 모두 300℃까지 전류 특성의 변화가 거의 없었으며 550℃에서도 양호한 정류 특성을 보였다. 상온에서의 Schottky barrier height와 이상인자(ideality factor) 및 specific on-resistance는 Ni/4H-SiC의 경우는 1.55eV, 1.3, 3.6×10/sup -2/Ω·㎠이었으며 Ni/6H-SiC Schottky 다이오드의 경우에 1.24eV, 1.2, 2.6×10/sup -2Ω·㎠/로 나타났다. 실험 결과 Ni/4H-SiC 및 Ni/6H-SiC Schottky 다이오드 모두 고온, 고전압 소자로서 우수한 특성을 나타냄이 입증되었다.

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성견 치주 골결손부에서의 수종의 차단막에 의한 치주조직 재생 효과;조직계측학적 메타 분석 (Effects of various membranes on periodontal tissue regeneration;a meta-analysis of the histomorphometry)

  • 이중석;임현창;채경준;정의원;김창성;이용근;조규성;채중규;김종관;최성호
    • Journal of Periodontal and Implant Science
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    • 제37권3호
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    • pp.465-478
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    • 2007
  • Various periodontal barrier membranes used in many clinical and experimental fields, and many recent studies of membranes have reported good results. To improve clinical results, selection of barrier membranes is an important factor. So, we need not only to evaluate various barrier mem-branes, but also to understand the property of barrier membranes appropriate to defect characteristics. For this purpose, this study reviewed available literature, evaluated comparable experimental models, and compared various barrier membranes. From above mentioned methods, the following conclusions are deduced. 1. In i-wall periodontal defect models, new bone formation showed a consistent result, almost 30% of the defect size. New cementum formations measured mostly 40% of the defect size, but showed more variations than new bone formations. This seems to be resulted form difference in experimental methods, so standardization in experimental methods is needed for future studies. 2. Application PLGA barrier membrane to periodontal defect demonstrated improved healing in new bone and new cementum. 3. There was a minimal periodontal regeneration with calcium sulfate barrier membrane only. But, there was better healing pattern in combination of calcium sulfate membrane with bone graft material, such as DFDBA, 4. There was no significant difference between the experimental group that used chitosan mem-brane only and the control group. But, in combination with bone graft material for space maintanence, periodontal regeneration was improved. Overall, Space maintenance is a critical factor for Guided tissue regeneration using barrier membranes. Also, a barrier membrane itself that has difficulty in maintaining space, achieved better result when used with graft material.

Sepsis induces variation of intestinal barrier function in different phase through nuclear factor kappa B signaling

  • Cao, Ying-Ya;Wang, Zhong-Han;Xu, Qian-Cheng;Chen, Qun;Wang, Zhen;Lu, Wei-Hua
    • The Korean Journal of Physiology and Pharmacology
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    • 제25권4호
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    • pp.375-383
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    • 2021
  • The intestinal barrier function disrupted in sepsis, while little is known about the variation in different phases of sepsis. In this study, mouse models of sepsis were established by caecal ligation and puncture (CLP). The H&E staining of sections and serum diamine oxidase concentration were evaluated at different timepoint after CLP. TUNEL assay and EdU staining were performed to evaluate the apoptosis and proliferation of intestinal epithelium. Relative protein expression was assessed by Western blotting and serum concentrations of pro-inflammatory cytokines was measured by ELISA. The disruption of intestinal barrier worsened in the first 24 h after the onset of sepsis and gradually recovered over the next 24 h. The percentage of apoptotic cell increased in the first 24 h and dropped at 48 h, accompanied with the proliferative rate of intestinal epithelium inhibited in the first 6 h and regained in the later period. Furthermore, the activity of nuclear factor kappa B (NF-κB) presented similar trend with the intestinal barrier function, shared positive correction with apoptosis of intestinal epithelium. These findings reveal the conversion process of intestinal barrier function in sepsis and this process is closely correlated with the activity of NF-κB signaling.

골관절염 환자의 운동양상과 운동장애 영향요인 (Exercise Pattern and Influencing Factor of Exercise Barrier in Patients with Osteoarthritis)

  • 김종임;김인자;강현숙;배상철;이은옥
    • 근관절건강학회지
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    • 제9권2호
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    • pp.135-143
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    • 2002
  • Exercise is an important strategy for health promotion in patients having osteoarthritis. But, lots of patients with osteoarthritis were underexercised. Exercise pattern and influencing factors of exercise barrier are not well-known. To address this issue, we studied the exercise pattern and influencing factors of exercise barrier in patients with osteoarthritis. The subjects of the study were 463 adult osteoarthritis (Mean age = 61.63 years) who had diagnosed osteoarthritis by rheumatologist. Data were gathered from May 1999 to February 2000 using a questionnaire and exercise barrier(Sallis et al, 1989), exercise pattern(Lee et al., 2000), physical status by WOMAC(Bellamy, 1989), socail support(Sallis et al., 1989), fatigue and pain using graphic rating scale, depression by CES-D(Radloff,1977). Data were analyzed with the SPSS win 6.0 using frequency, ANOVA, Stepwise multiple regression. The results of this study were as follows; 1) 56.4% of sample was 'do not exercise at all', 'longer rest than exercise', was 15.9%, 'longer exercise than rest' was 7.2%, 'exercise regularly' was 20.5%. 2) Social support (F=10.349, p=0.000) and exercise barrier(F=4.455, p=0.004) were showed significantly difference by exercise pattern. 3) Influencing factors of exercise barrier were depression and social support. Thoses explained 13.3% of exercise barrier. In conclusion, half of osteoarthritis patient did not do exercise and it was shown that depression and social support were major influencing factors to exercise barrier. The results of this study can be applied to develop the health promoting educational program for patients with osteoarthritis.

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Glutamate attenuates lipopolysaccharide induced intestinal barrier injury by regulating corticotropin-releasing factor pathway in weaned pigs

  • Guo, Junjie;Liang, Tianzeng;Chen, Huifu;Li, Xiangen;Ren, Xiaorui;Wang, Xiuying;Xiao, Kan;Zhao, Jiangchao;Zhu, Huiling;Liu, Yulan
    • Animal Bioscience
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    • 제35권8호
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    • pp.1235-1249
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    • 2022
  • Objective: The purpose of this study was to evaluate the protection of glutamate (GLU) against the impairment in intestinal barrier function induced by lipopolysaccharide (LPS) stress in weaned pigs. Methods: Twenty-four weaned pigs were divided into four treatments containing: i) non-challenged control, ii) LPS-challenged control, iii) LPS+1.0% GLU, and iv) LPS+2.0% GLU. On day 28, pigs were treated with LPS or saline. Blood samples were collected at 0, 2, and 4 h post-injection. After blood samples collection at 4 h, all pigs were slaughtered, and spleen, mesenteric lymph nodes, liver and intestinal samples were obtained. Results: Dietary GLU supplementation inhibited the LPS-induced oxidative stress in pigs, as demonstrated by reduced malondialdehyde level and increased glutathione level in jejunum. Diets supplemented with GLU enhanced villus height, villus height/crypt depth and claudin-1 expression, attenuated intestinal histology and ultrastructure impairment induced by LPS. Moreover, GLU supplementation reversed intestinal intraepithelial lymphocyte number decrease and mast cell number increase induced by LPS stress. GLU reduced serum cortisol concentration at 4 h after LPS stress and downregulated the mRNA expression of intestinal corticotropin-releasing factor signal (corticotrophin-releasing factor [CRF], CRF receptor 1 [CRFR1], glucocorticoid receptor, tryptase, nerve growth factor, tyrosine kinase receptor A), and prevented mast cell activation. GLU upregulated the mRNA expression of intestinal transforming growth factor β. Conclusion: These findings indicate that GLU attenuates LPS-induced intestinal mucosal barrier injury, which is associated with modulating CRF signaling pathway.

Effect of Polysaccharides from Acanthopanax senticosus on Intestinal Mucosal Barrier of Escherichia coli Lipopolysaccharide Challenged Mice

  • Han, Jie;Xu, Yunhe;Yang, Di;Yu, Ning;Bai, Zishan;Bian, Lianquan
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권1호
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    • pp.134-141
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    • 2016
  • To investigate the role of polysaccharide from Acanthopanax senticosus (ASPS) in preventing lipopolysaccharide (LPS)-induced intestinal injury, 18 mice (at 5 wk of age) were assigned to three groups with 6 replicates of one mouse each. Mice were administrated by oral gavage with or without ASPS (300 mg/kg body weight) for 14 days and were injected with saline or LPS at 15 days. Intestinal samples were collected at 4 h post-challenge. The results showed that ASPS ameliorated LPS-induced deterioration of digestive ability of LPS-challenged mice, indicated by an increase in intestinal lactase activity (45%, p<0.05), and the intestinal morphology, as proved by improved villus height (20.84%, p<0.05) and villus height:crypt depth ratio (42%, p<0.05), and lower crypt depth in jejunum (15.55%, p<0.05), as well as enhanced intestinal tight junction proteins expression involving occludin-1 (71.43%, p<0.05). ASPS also prevented intestinal inflammation response, supported by decrease in intestinal inflammatory mediators including tumor necrosis factor ${\alpha}$ (22.28%, p<0.05) and heat shock protein (HSP70) (77.42%, p<0.05). In addition, intestinal mucus layers were also improved by ASPS, as indicated by the increase in number of goblet cells (24.89%, p<0.05) and intestinal trefoil peptide (17.75%, p<0.05). Finally, ASPS facilitated mRNA expression of epidermal growth factor (100%, p<0.05) and its receptor (200%, p<0.05) gene. These results indicate that ASPS can prevent intestinal mucosal barrier injury under inflammatory conditions, which may be associated with up-regulating gene mRNA expression of epidermal growth factor and its receptor.