• Title/Summary/Keyword: barrier factor

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이중양분선택형 질문법을 이용한 CVM에 의한 지하철 역사 Barrier-free 시설의 가치분석 (Value Analysis of Barrier-free Facilities at Subway Stations Using CVM with a Double Bounded Dichotomous Choice Question)

  • 정헌영;백상근;백은상
    • 대한교통학회지
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    • 제26권5호
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    • pp.205-216
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    • 2008
  • 향후 장애인과 고령인구의 지속적인 증가로 인해 교통약자의 통행수요는 확대될 것이며, 이에 따라 고령자, 장애자들이 안전하고 쾌적하게 생활할 수 있도록 지원하는 사회간접자본의 정비가 요구되고 있다. 무엇보다도 대중교통관련 시설의 Barrier-free화(무장애화)는 시급한 사안이라 보아진다. 본 연구의 목적은 공공재의 가치추정에 있어 효율적인 방법론인 이중양분선택형 질문법에 의한 CVM(조건부가치측정법)을 이용하여 지하철 역사의 Barrier-free 시설의 가치를 추정하고, 생존분석을 통해 지하철 이용자들의 지불의사금액에 영향을 미치는 요인을 분석하고자 한다. 본 연구의 결과, 에스컬레이터와 엘리베이터에 대한 평균지불의사금액이 장애인개찰기나 단차해소시설의 평균지불의사금액에 비해 상대적으로 높게 나와 실제 Barrier-free 시설의 확충에 있어서 이용편의시설보다는 이동편의시설을 먼저 시급히 설치해 나가야 함을 시사하고 있다. 또한 각 Barrier-free 시설에 대한 교통약자의 평균지불의사금액이 일반인의 평균지불의사금액에 비해 훨씬 높아 일반인과 비교할 때 교통약자들이 Barrier-free 시설의 가치를 상대적으로 높게 평가하고 있었다.

온도변화에 따른 백금 실리사이드-엔 실리콘 접합의 전자 터널링 특성 (Electron Tunneling Characteristics of PtSi-nSi Junctions according to Temperature Variations)

  • 장창덕;이정석;이광우;이용재
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.87-91
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    • 1998
  • In this paper, We analyzed the current-voltage characteristics with n-type silicon substrates concentration and temperature variations (Room temperature, 50$^{\circ}C$, 75$^{\circ}C$) in platinum silicide and silicon junction. The electrical parameters of measurement are turn-on voltage, saturation current, ideality factor, barrier height, dynamic resistance in forward bias and reverse breakdown voltage according to variations of junction concentration of substrates and measurement temperature variations. As a result, the forward turn-on voltage, reverse breakdown voltage, barrier height and dynamic resistance were decreased but saturation currents and ideality factor were increased by substrates increased concentration variations in platinum silicide and n-silicon junction. In increased measurement temperature (RT, 50$^{\circ}C$, 75$^{\circ}C$), the extracted electrical parameter values of characteristics were rises by increased temperature variations according to the forward and reverse bias.

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반응성 플라즈마를 이용한 태양전지용 Si기판의 표면 처리 (Surface treatment of Si wafer for solar cell using reactive plasma method)

  • 박병욱;곽동주;성열문
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1305-1306
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    • 2007
  • To lower the fabrication cost of silicon solar cells, a surface treatment using a dielectric barrier discharge instead of a wet cleaning technique was examined on electrode surfaces on silicon solar cells. The fill factor obtained through measuring current-voltage characteristics was evaluated, and the treated surface state was characterized by energy-dispersive X-ray. It was found that the dielectric barrier discharge effectively activated the electrode surface and the surface treatment on finger electrodes contributed greatly to improve the fill factor.

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Intrinsic and Thermodynamic Effects on the Structure and Energy of the S$_N$2 Transition State$^*$

  • Lee, Ik-Choon;Seo, Heon-Su
    • Bulletin of the Korean Chemical Society
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    • 제7권6호
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    • pp.448-453
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    • 1986
  • Two contributions to the activation barrier of the $S_N2$ reaction, intrinsic and thermodynamic, are discussed in connection with the predictive power of various rate-equilibrium relationships. It has been shown that the PES models can only give correct predictions of changes in structure and energy of the transition state if the activation barrier is dictated by the thermodynamic factor. We concluded that the identity and dissociative $S_N2$ reactions are dominated by the intrinsic component while associative $S_N2$ reactions are predominantly of thermodynamic controlled. Thus in the former cases, the PES models fail, whereas in the latter cases predictions based on the intrinsic factor, the quantum mechanical models, fail. Finally in a general case of equal contributions by thermodynamic and intrinsic factors, the $SN_2$ reaction proceeds by a synchronous process with zero net charge on the reaction center, for which predictions of substituent effects will be the same as for the intrinsic control case.

In vivo evidence for brain-to-blood efflux transport of taurine and regulation of this transport by tumor necrosis factor-$\alpha$ at the blood-brain barrier

  • Lee, Na-Young;Kang, Young-Sook
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.69.2-69.2
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    • 2003
  • The purpose of this study is to examine whether the efflux system for taurine from brain to blood is present on the blood-brain barrier (BBB) using the brain efflux index (BEl) method and taurine transport system is regulated by CNS cell damage with oxidative stress agent such as diethyl maleate (DEM) or tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in vivo. [$^3$H]Taurine was microinjected into parietal cortex area 2 (Par2) of the rat brain, and was eliminated from the brain with efflux transport rate of 1.22 10$\^$-2//min, and the process is saturable with a $K_{m}$ of 43.5 ${\mu}$M. (omitted)

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주택의 특성으로서 접근성에 대한 가치분석 (A Value Analysis of Accessibility as an Attribute of Housing)

  • 이소영
    • 한국주거학회논문집
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    • 제22권4호
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    • pp.43-50
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    • 2011
  • In an aging society, as the number of people with disabilities increases concerns are raised about the quality of life of these people and their access to a safe environment becomes important. The purpose of this study is to find out the value of accessibility as an attribute of housing. To estimate the value of accessible, barrier-free housing, this study uses the Contingent Valuation Method (CVM) and analyzes the factors which affect the Willingness To Pay (WTP) of survey respondents by using Survival Analysis. In addition, the importance and satisfaction of barrier-free facilities in the dwellings of survey respondents was investigated. Since aging could be an important factor in influencing the need for accessibility, this study surveyed two age groups, one group (212 respondents) of people below the age of 65 and the other (162 respondents) of people above 65. The results of this study show that respondents would pay on average 2.67% more for being barrier-free when answering an open-ended question and 3.87% more for barrier-free housing when using the double referendum model. This is the increase in value that the respondents perceive as a consequence of removing all the architectural barriers from a dwelling. On average, elderly respondents would pay 2.99% of housing price for accessible features compared to 4.40% of the younger group. However, if the elderly who have willingness to pay for accessibility, the value the older group put on barrier-free housing was higher than the value perceived by the younger group. Factors that influence the WTP are importance of barrier-free facilities, education level and housing type. The value of dwellings without barriers estimated in this study shows the potential size and value of this kind of housing market to the housing development sector.

Investigation of TaNx diffusion barrier properties using Plasma-Enhanced ALD for copper interconnection

  • 한동석;문대용;권태석;김웅선;황창묵;박종완
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.178-178
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    • 2010
  • With the scaling down of ULSI(Ultra Large Scale Integration) circuit of CMOS(Complementary Metal Oxide Semiconductor)based electronic devices, the electronic devices become more faster and smaller size that are promising field of semiconductor market. However, very narrow line width has some disadvantages. For example, because of narrow line width, deposition of conformal and thin barrier is difficult. Besides, proportion of barrier width is large, thus resistance is high. Conventional PVD(Physical Vapor Deposition) thin films are not able to gain a good quality and conformal layer. Hence, in order to get over these side effects, deposition of thin layer used of ALD(Atomic Layer Deposition) is important factor. Furthermore, it is essential that copper atomic diffusion into dielectric layer such as silicon oxide and hafnium oxide. If copper line is not surrounded by diffusion barrier, it cause the leakage current and devices degradation. There are some possible methods for improving the these secondary effects. In this study, TaNx, is used of Tertiarybutylimido tris (ethylamethlamino) tantalum (TBITEMAT), was deposited on the 24nm sized trench silicon oxide/silicon bi-layer substrate with good step coverage and high quality film using plasma enhanced atomic layer deposition (PEALD). And then copper was deposited on TaNx barrier using same deposition method. The thickness of TaNx was 4~5 nm. TaNx film was deposited the condition of under $300^{\circ}C$ and copper deposition temperature was under $120^{\circ}C$, and feeding time of TaNx and copper were 5 seconds and 5 seconds, relatively. Purge time of TaNx and copper films were 10 seconds and 6 seconds, relatively. XRD, TEM, AFM, I-V measurement(for testing leakage current and stability) were used to analyze this work. With this work, thin barrier layer(4~5nm) with deposited PEALD has good step coverage and good thermal stability. So the barrier properties of PEALD TaNx film are desirable for copper interconnection.

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Contributions of HO-1-Dependent MAPK to Regulating Intestinal Barrier Disruption

  • Zhang, Zhenling;Zhang, Qiuping;Li, Fang;Xin, Yi;Duan, Zhijun
    • Biomolecules & Therapeutics
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    • 제29권2호
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    • pp.175-183
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    • 2021
  • The mitogen-activated protein kinase (MAPK) pathway controls intestinal epithelial barrier permeability by regulating tight junctions (TJs) and epithelial cells damage. Heme oxygenase-1 (HO-1) and carbon monoxide (CO) protect the intestinal epithelial barrier function, but the molecular mechanism is not yet clarified. MAPK activation and barrier permeability were studied using monolayers of Caco-2 cells treated with tissue necrosis factor α (TNF-α) transfected with FUGW-HO-1 or pLKO.1-sh-HO-1 plasmid. Intestinal mucosal barrier permeability and MAPK activation were also investigated using carbon tetrachloride (CCl4) administration with CoPP (a HO-1 inducer), ZnPP (a HO-1 inhibitor), CO releasing molecule 2 (CORM-2), or inactived-CORM-2-treated wild-type mice and mice with HO-1 deficiency in intestinal epithelial cells. TNF-α increased epithelial TJ disruption and cleaved caspase-3 expression, induced ERK, p38, and JNK phosphorylation. In addition, HO-1 blocked TNF-α-induced increase in epithelial TJs disruption, cleaved caspase-3 expression, as well as ERK, p38, and JNK phosphorylation in an HO-1-dependent manner. CoPP and CORM-2 directly ameliorated intestinal mucosal injury, attenuated TJ disruption and cleaved caspase-3 expression, and inhibited epithelial ERK, p38, and JNK phosphorylation after chronic CCl4 injection. Conversely, ZnPP completely reversed these effects. Furthermore, mice with intestinal epithelial HO-1 deficient exhibited a robust increase in mucosal TJs disruption, cleaved caspase-3 expression, and MAPKs activation as compared to the control group mice. These data demonstrated that HO-1-dependent MAPK signaling inhibition preserves the intestinal mucosal barrier integrity by abrogating TJ dysregulation and epithelial cell damage. The differential targeting of gut HO-1-MAPK axis leads to improved intestinal disease therapy.

Berberine Prevents Intestinal Mucosal Barrier Damage During Early Phase of Sepsis in Rat through the Toll-Like Receptors Signaling Pathway

  • Li, Guo-Xun;Wang, Xi-Mo;Jiang, Tao;Gong, Jian-Feng;Niu, Ling-Ying;Li, Ning
    • The Korean Journal of Physiology and Pharmacology
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    • 제19권1호
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    • pp.1-7
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    • 2015
  • Our previous study has shown berberine prevents damage to the intestinal mucosal barrier during early phase of sepsis in rat through mechanisms independent of the NOD-like receptors signaling pathway. In this study, we explored the regulatory effects of berberine on Toll-like receptors during the intestinal mucosal damaging process in rats. Male Sprague-Dawlay (SD) rats were treated with berberine for 5 d before undergoing cecal ligation and puncture (CLP) to induce polymicrobial sepsis. The expression of Toll-like receptor 2 (TLR 2), TLR 4, TLR 9, the activity of nuclear factor-kappa B ($NF-{\kappa}B$), the levels of selected cytokines and chemokines, percentage of cell death in intestinal epithelial cells, and mucosal permeability were investigated at 0, 2, 6, 12 and 24 h after CLP. Results showed that the tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-6 (IL-6) level were significantly lower in berberine-treated rats compared to the control animals. Conversely, the expression level of tight junction proteins, percentage of cell death in intestinal epithelial cells and the mucosal permeability were significantly higher in berberine-treated rats. The mRNA expression of TLR 2, TLR 4, and TLR 9 were significantly affected by berberine treatment. Our results indicate that pretreatment with berberine attenuates tissue injury and protects the intestinal mucosal barrier in early phase of sepsis and this may possibly have been mediated through the TLRs pathway.

다중 방책 연구

  • 조덕운;이상용
    • 한국국방경영분석학회지
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    • 제11권2호
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    • pp.6-14
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    • 1985
  • The layered multi-barrier defense situation against penetrating enemy threat is analytically modeled towards minimizing the penetration probability. Each layer is characterized by probability of detection and probability of kill given detection. The two capabilities are assumed independent. Detection in a layer, however, affects detection performance in subsequent layers. The following three models were formulated and investigated: (1) 'Model A' permits increase of detection performance in only the next barrier, (2) 'Model B' permits the increase in all subsequent barriers linearly, and (3) 'Model C' expresses the increase in an asymptotic exponential way. The best and the worst barrier combinations are determined through model exercise and model performances are compared through sensitivity analysis for the 'intensification factor.'

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