• Title/Summary/Keyword: barrier well

검색결과 760건 처리시간 0.027초

20-30대 한국인의 경피수분 손실도 연구 (The study on the transepidermal water loss of the Korean twenties and thirties)

  • 차재훈;남혜정;김규석;신윤진;김윤범
    • 한방안이비인후피부과학회지
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    • 제20권2호통권33호
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    • pp.179-186
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    • 2007
  • Objective : Skin barrier protects skin against harmful environment. Its function includes antimicrobial barrier as well as physical barrier. But there are few studies about skin barrier function about men and women who don't have skin disease. The aim of this study is to investigate skin barrier function healthy men and women show. Method : There are many ways to measure skin barrier function, but lately transepidermal water loss is mainly used to know skin barrier function. Transepidermal water loss was measured over eight four the Korean twenties and thirties who don't have skin disease from March 14th, 2007 to March 16th 2007. We surveyed cubital fossa and cheek beside nose to measure transepidermal water loss and used vapometer. Result : After analyzed data, we concluded that cheek showed higher transepidermal water loss than cuital fossa. At cheek, the thirties had higher transepidermal water loss than the twenties. The male got higher transepidermal water loss than the female at cheek and in the average. And temperature and humidity effected on transepidermal water loss. Conclusion: In our study, it was observed that temperature and humidity effected on transepidermal water loss. In traditional korean medicine, the inbalance of cold(寒), heat(熱), dryness(燥), wetness(濕) makes many diseases and the inbalance of them induces dameum(痰飮) and the disorder of blood flow. Dameum(痰飮) and the disorder of blood flow make skin diseases made by abnormal skin barrier function in many ways. So we need to study dameum(痰飮) and the disorder of blood flow to take care of patients who have abnormal skin barrier function.

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Inclusion of Silicon Delta-doped Two-dimensional Electron Gas Layer on Multi-quantum Well Nano-structures of Blue Light Emitting Diodes

  • Kim, Keun-Joo
    • Transactions on Electrical and Electronic Materials
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    • 제5권5호
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    • pp.173-179
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    • 2004
  • The influence of heavily Si impurity doping in the GaN barrier of InGaN/GaN multi-quantum well structures of blue light emitting diodes were investigated by growing samples in metal-organic chemical vapor deposition. The delta-doped sample was compared to the sample with the undoped barrier. The delta-doped sample shows the tunneling behavior and forms the energy level of 0.32 eV for tunneling and the photoemission of the 450-nm band. The photo-luminescence shows the blue-shifted broad band of the radiative transition due to the inclusion of Si delta-doped layer indicating that the delta doping effect acts to form the higher energy level than that of quantum well. The dislocation may provide the carrier tunneling channel and plays as a source of acceptor. During the tunneling of hot carrier, there was no light emission.

Cr- 및 Ni- 소스/드레인 쇼트키 박막 트랜지스터의 장벽 특성에 대한 실험 및 모델링 연구 (Experimental and Simulation Study of Barrier Properties in Schottky Barrier Thin-Film Transistors with Cr- and Ni- Source/Drain Contacts)

  • 정지철;문경숙;구상모
    • 한국전기전자재료학회논문지
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    • 제23권10호
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    • pp.763-766
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    • 2010
  • By improving the conducting process of metal source/drain (S/D) in direct contact with the channel, schottky barrier metal-oxide-semiconductor field effect transistors (SB MOSFETs) reveal low extrinsic parasitic resistances, offer easy processing and allow for well-defined device geometries down to the smallest dimensions. In this work, we investigated the arrhenius plots of the SB MOSFETs with different S/D schottky barrier (SB) heights between simulated and experimental current-voltage characteristics. We fabricated SB MOSFETs using difference S/D metals such as Cr (${\Phi}_{Cr}$ ~4.5 eV) and Ni (${\Phi}_{Ni}$~5.2 eV), respectively. Schottky barrier height (${\Phi}_B$) of the fabricated devices were measured to be 0.25~0.31 eV (Cr-S/D device) and 0.16~0.18 eV (Ni-S/D device), respectively in the temperature range of 300 K and 475 K. The experimental results have been compared with 2-dimensional simulations, which allowed bandgap diagram analysis.

Extravasating Neutrophil-derived Microparticles Preserve Vascular Barrier Function in Inflamed Tissue

  • Lim, Kihong;Sumagin, Ronen;Hyun, Young-Min
    • IMMUNE NETWORK
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    • 제13권3호
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    • pp.102-106
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    • 2013
  • Emerging evidence suggests that gap formation and opening of the endothelial junctions during leukocyte extravasation is actively controlled to maintain the integrity of the vascular barrier. While the role for endothelial cells to this process has been well defined, it is not clear whether leukocytes are also actively contributing to endothelial barrier function. We have recently showed that extravasating leukocytes deposit microparticles on the subendothelium during the late stages of extravasation, which is LFA-1 dependent. Using multiphotonintravital microscopy (MP-IVM) of mouse cremaster muscle vessels in the current work, we show that microparticle formation and deposition maintains the integrity of the microvascular barrier during leukocyte extravasation. Inhibition of neutrophil-derived microparticle formation resulted in dramatically increased vascular leakage. These findings suggest that deposition of microparticles during neutrophil extravasation is essential for maintaining endothelial barrier function and may result in temporal difference between neutrophil extravasation and an increase in vascular leakage.

LNGC 2차 방벽에 적용된 Aramid 섬유의 Weibull 통계 분석을 이용한 피로특성 평가 (Estimation of Fatigue Characteristics Using Weibull Statistical Analysis with Aramid Fiber on LNGC Secondary Barrier)

  • 박진형;오동진;김민규;김명현
    • 대한조선학회논문집
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    • 제54권5호
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    • pp.415-420
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    • 2017
  • Insulation systems in Liquefied Natural Gas Carriers (LNGC) are vulnerable to sloshing impact and fatigue loads because of waves. If gas leaks into the primary barrier, the Flexible Secondary Barrier (FSB) prevents the leakage of gas in this system. Fatigue strength of the FSB largely depends on the behavior of composite materials. In this study, a new system is applied to the FSB using aramid fiber to improve the fatigue strength of the secondary barrier, with the intention of replacing conventional E-glass fibers. The manufacturing method involved varying the ratio of the aramid fiber to the E-glass fiber for optimum design of the FSB. The fatigue tests results of the secondary barrier using aramid fiber were superior to that using E-glass fiber. The statistical analysis is performed to obtain the fatigue test results and estimate the probability of failure as well as the design guideline of LNGC secondary barriers.

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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The Effect of Multi-lamellar Emulsion (MLE) on Skin Barrier Function: Can an Improve Permeability Barrier Provide a Solution for Itching due to Skin Barrier Malfunction\ulcorner

  • Youm, Jong-kyung;Kim, Yang-hee;Park, Byeong-deog;Jeong, Se-kyoo;Park, Eung-ho;Ahn, Sung-ku;Lee, Seung-hun
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.765-779
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    • 2003
  • Physiological lipid mixtures comprised of cholesterol, ceramide and free fatty acid better maintain epidermal homeostasis and have been recently used for dermatoses induced by skin barrier damage, for example for atopic dermatitis and xerotic skin. Itching and dry atopic dermatitis of the skin may be related to altered skin barrier function. In a previous study, the use of multi-lamellar emulsion (MLE), which is a lipid mixtures containing cholesterol, pseudoceramide and free fatty acid, has been shown to accelerate the recovery of the epidermal permeability barrier. In this study, we assessed the efficacy of MLE compared with a currently used anti-itch moisturizer (AIM), the active ingredients of which are menthol and camphor, on barrier recovery after barrier disruption. To clarify the effect of MLE and AIM after acute barrier perturbation, we measured the relation between transepidermal water loss (TEWL) and the barrier recovery rate at 3, 6, 24, and 48 hours after tape stripping hairless mice and then observed changes in the stratum corneum (SC), including the intercellular lipid structure and secretion of lamellar bodies, by electron microscopy. MLE treated skin recover skin barrier function more rapidly, and AIM treated skin delayed barrier repair. Morphological changes in the epidermis, of MLE treated skin revealed well-conserved lipid multi-lamellar structures at 24 h after tape stripping, whereas AIM treated skin showed altered lamellar bilayers within the SC interstices at 48 h. In addition, MLE treated skin showed an increase in the number of LBs and in their secretions and a decrease in the number of SC layers versus AIM treated skin. These results suggest that MLE may accelerate the production of an epidermal permeability barrier in hairless mice by increasing the number and secretion of LB and improve the dryness and itch associated with an altered epidermal permeability barrier.

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모형축적 실험에 의한 유한길이 방음벽의 음향특성 연구 (A Study on the Acoustical Characteristics of the Finite Noise Barrier by a Scale Model Test)

  • 황철호;정성수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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    • pp.650-658
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    • 1998
  • The pressure level and the insertion loss at the receiving point behind finite length noise barriers are measured in an anechoic room by scale model test. The measured sound pressure level which are conducted under the several experimental conditions such as the length of the noise barrier, the distance between the noise barrier and the receiving point, the number of noise barriers, and the existence of the reflective building behind receiving point) and the insertion loss of a noise barrier having simple shape are well agreed with theoretical calculation which is based on Lam's model.

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Material Design for the Fabrication of Barrier Ribs with High Aspect Ratio of Plasma Display Panel by X-ray Lithography

  • Ryu, Seung-Min;Yang, Dong-Yol;So, Jae-Yong;Park, Lee-Soon
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.989-992
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    • 2008
  • X-ray lithography is one of the most powerful processes in the fabrication of nano/micro structures with a high aspect ratio. This process enables the fabrication of ultra-thin barrier ribs for PDP using X-ray sensitive paste. In this paper, organic material including photo-monomers, photo-oligomers, binder polymer and additives as well as inorganic powders with different size were optimized to fabricate high aspect ratio barrier rib pattern for PDP.

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Impact of Energy Relaxation of Channel Electrons on Drain-Induced Barrier Lowering in Nano-Scale Si-Based MOSFETs

  • Mao, Ling-Feng
    • ETRI Journal
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    • 제39권2호
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    • pp.284-291
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    • 2017
  • Drain-induced barrier lowering (DIBL) is one of the main parameters employed to indicate the short-channel effect for nano metal-oxide semiconductor field-effect transistors (MOSFETs). We propose a new physical model of the DIBL effect under two-dimensional approximations based on the energy-conservation equation for channel electrons in FETs, which is different from the former field-penetration model. The DIBL is caused by lowering of the effective potential barrier height seen by the channel electrons because a lateral channel electric field results in an increase in the average kinetic energy of the channel electrons. The channel length, temperature, and doping concentration-dependent DIBL effects predicted by the proposed physical model agree well with the experimental data and simulation results reported in Nature and other journals.