• 제목/요약/키워드: Adhesion Characteristic

검색결과 142건 처리시간 0.034초

염증성 치은조직에서 Cell Adhesion Molecule의 발현에 관한 연구 (Expression of Adhesion Molecule in Inflammatory Gingival Tissue)

  • 박경근;김은철;유형근;신형식
    • Journal of Periodontal and Implant Science
    • /
    • 제26권3호
    • /
    • pp.655-668
    • /
    • 1996
  • The change in vascular adhesion molecule expression and number of infiltrating leukocytes were investigated irnmunohistochemically in clinically healthy and inflammed gingiva. Monoclonal antibodies to ICAM-1, VCAM-1 and E-cadherin were used to identify positive vessels and leukocyte within gingival biopsies. 10 healthy gingiva and 30 inflammed gingiva was resected by clinical crown lengthening and modified Widman flap operation, respectively. Leukocyte entry into tissues at sites of inflammation is controlled by the interaction between adhesion molecule and endothelium. Because of rapid and severe destructive periodontal disease that is remarkable leukocyte adhesion deficiency, it is very important to unerdstand the mechanism of host defence against periodontal disease. The purpose of this investigation was the characterization of the presence and distribution of the adhesion molecule(ICAM-1, VCAM-1 and Evcadherin) in inflammatory gingival tissues compared to clinically healthy gingiva. The results were as followed; 1. ICAM-1 was distributed on basal layer, endothelium and mononuclear cells 10 healthy gingiva but inflammed gingiva was observed stronger stain than healthy gingiva. 2. Rare expression was observed in both group but few positive VCAM-1 cells were investigated in inflammatory gingival tissues 3. E-cadherin was expressed in only epithelium and reduced expression was observed in inflammatory gingival tissues. ICAM-1, VCAM-1 showed more expression in inflammatory tissues compared to healthy gingiva. Conversely, E-cadherin revealed a opposite result. These finding demonstrate a characteristic distribution and degree of adhesion molecule in healthy and inflammatory gingival tissues. But it is suggested that more detail study be progressive associated with leukocyte adhesion molecule to determine characterization of periodontal disease.

  • PDF

아크용사시 불활성가스에 의한 피막밀착강도 향상에 관한 연구 (A study on the improvement of coating film characteristic in arc spraying by using the inert gas)

  • 김영식;여욱종
    • Journal of Welding and Joining
    • /
    • 제5권2호
    • /
    • pp.17-26
    • /
    • 1987
  • In this study, the experiments were carried out for the purpose of establishment of the arc sparing method which reducing oxides or oxide film by using the inert gas as the carrier gas of atomizing particles. Main results obtained are as follows; 1. Oxides and oxide film which lower the adhesion strength are largely reduced by using the inert gas as the carrier gas of atomizing particles, and adhesion strength of coating film are improved. 2. The coating film characteristics appear to be no difference between the inert gas arc spraying in air environment and that in argon gas environment. 3. Inert gas arc spraying using argon as the carrie gas has higher reduction rate of composition element in coating film than compressed air spraying does.

  • PDF

차량 견인특성모델링 및 점착력 추정 (Adhesion Estimation and Modeling on Traction Characteristic of Vehicle)

  • 변윤섭;김민수;목재균;김영철
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2009년도 제40회 하계학술대회
    • /
    • pp.1765_1766
    • /
    • 2009
  • In this paper, we propose the mathematical model for the vehicle system and the observer for adhesion force. To model the dynamic properties of vehicle system, we have considered two fundamental parts. The first part is the motion equations for vehicle based on Newton's second law. The second part is the torque dynamics of the traction motor. These parts are affected by outer conditions such as adhesive coefficient, running resistance and gradient resistance. The each parts are presented by the numerical formula. From two equations, we get the observer on adhesion force. Simulation results show that the proposed observer have the good performance compared with the normal observer.

  • PDF

나노 다이아몬드 코팅박막의 기계적 특성 평가를 위한 계측시스템의 개발 (Development of the Measurement System for Evaluating Mechanical Properties of Nano-diamond Coated Film)

  • 권현규;이소진;권용민
    • 반도체디스플레이기술학회지
    • /
    • 제18권1호
    • /
    • pp.25-31
    • /
    • 2019
  • In this study, a new adhesion evaluating equipment and data processing methods were developed to overcome some limitations of existing evaluating equipment. Nano-diamond coated tool is a specimen of experiment. When applying frictional force and shear force on the specimen by a rotating polishing pad, delamination occurs at a moment. During each experiment, the vibration, load, and torque is obtained by accelerometer, loadcell and torque s+ kpensor. Frictional force and coefficient of friction are obtained by calculating torque and load. Based on FFT transformation, acceleration is processed and analyzed. As a result, the moment of delamination and the load at that time can be detected by the new developed equipment and measurement system. Finally, we call this load as an Adhesion force.

상압 플라즈마 표면처리에 의한 고분자 재질의 접착특성 변화 (Adhesion Characteristics of Polymer Material Treated by Atmospheric Pressure Plasma)

  • 서승호;장성환;유영은;정재동
    • 대한기계학회논문집B
    • /
    • 제35권5호
    • /
    • pp.445-450
    • /
    • 2011
  • 본 연구에서는 상압 플라즈마를 발생시켜 고분자 재료의 표면 자유에너지와 접착력의 변화를 조사하였다. 고분자 재질은 PC, PET, EVA 를 사용하였으며 표면자유에너지 변화를 관찰하기 위해 Di water 와 diiodomethane을 사용하여 접촉각을 측정하였다. 플라즈마 처리에 따른 접착력의 변화를 관찰하기 위해 PET 필름에 고분자 필름을 부착시켜 $180^{\circ}$ peel test 를 수행하였다. 그 결과 PET 필름의 표면자유에너지 및 접착력이 가장 큰 것을 확인할 수 있었으며, 상압 플라즈마 표면처리 공정은 필름 계면의 접착력을 크게 증가시켜 주는 것을 확인하였다.

The Flexible Characteristic of Reversible and Robust Nanohair Fastener

  • Park, Seung-Ho;Yoon, Young-Seok;Lee, Dong-Woo;Lee, Dong-Ik;You, Kyoung-Hwan;Pang, Chang-Hyun;Suh, Kahp-Yang
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
    • /
    • pp.432-432
    • /
    • 2011
  • Dry adhesion caused by Nanoscale contact comes up to important scientific issue. Herein, we introduce bendable nanohairy locking fastener system with high shear strength and mechanically flexible backing. The polymeric patches like velcro are composed of an array of straight nanohairs with 100 nm diameter and $1{\mu}m$ height. To fabricate high aspect vertical nanohairs, we used UV molding method with appropriately flexible and rigid polyurethane acrylate material on PET substrate. Two identical nanohairy patches are easily merged and locked each other induced by van der Waals force. Because nanohairs can be arrayed with high density ${\sim}4{\times}10^8/cm^2$, we can obtain high shear adhesion force on flat surface (~22 N/$cm^2$). Furthermore, we can obtian nanohairy locking system with maximum shear adhesion ~48 N/$cm^2$ of curved surface due to flexibility of PET substrate. We confirm the tendency that shear adhesion force increases, as radius of curvature increases.

  • PDF

표면 에너지 원리를 이용한 칩실 포장의 초기 점착력 특성 연구 (Study on Early Adhesive Characteristic of Chip Seals Using a Surface Energy Approach)

  • 임정혁
    • 한국도로학회논문집
    • /
    • 제17권6호
    • /
    • pp.47-54
    • /
    • 2015
  • PURPOSES : The objective of this study is to evaluate the early adhesive characteristic of asphalt emulsions, including polymer-modified emulsions, for chip seals using the surface energy concept, the bitumen bond strength (BBS) test, and the Vialit test. METHODS : Two general methods, the BBS test and Vialit test, were applied to investigate the bond strength and the aggregate loss, respectively. A new theory, the surface free energy (SFE) theory, was used to evaluate the adhesive characteristic between the emulsion and the aggregate. Based on the theory, the contact angles were measured, and then the surface energy components were calculated. Using those components, the work of adhesion (Wa) was calculated for each emulsion. To ensure reliable results, all the tests were performed under the same conditions, i.e., at $25^{\circ}C$ for 240 minutes of curing time. For the materials, three emulsions (CRS-2, CRS-2L, and CRS-2P) and one aggregate type (granite) were employed. RESULTS AND CONCLUSIONS : Under the same conditions, the modified emulsions showed better adhesive characteristics and curing behaviors than the unmodified emulsions. In addition, there was no significant difference between the various modified emulsions. One of the important findings is that the analysis by Wa presents more sensitive results than other methods. The results of the Wa showed that the CRS-2P emulsion has the best adhesive characteristics. Consequently, the use of modified emulsions for chip seals could prevent aggregate loss and allow open traffic earlier.

댄스 스포츠 의상의 조형성과 미적 특성에 관한 연구 (A Study on Formative and Aesthetic Characteristics of the Costume of Dance Sports)

  • 김미영
    • 복식문화연구
    • /
    • 제14권6호
    • /
    • pp.1042-1055
    • /
    • 2006
  • The purpose of this study is to consider the formative characteristics of dance sports from such points of view as shapes, colors, material and decorations, and to examine artistic characteristics that are expressed through those elements. As a result, this study shows five artistic characteristics as follows; First, rhythmic characteristic is expressed with repeat of lines that is formed by pleats, shirring or gather, with duplication of ruffle's wave, with gradation of colors, with Moire-effect that is generated with overlap of see-through material, with glossy material that reflects lights to a great extent, with fringe. Second, bodily characteristic emphasizes the beauty of human bodies through direct or indirect body exposure by way of cut-and-open, see-throughness or close adhesion. Third, decorative characteristic is shown with beads, fringe, ruffle, embroidery, shirring, binding, or feather. Fourth, the beauty of female body is manifested to express eroticism, which is culminated by body exposure, body consciousness, use of illuminating or see-through material or colorful trimming. Finally, elegant characteristic is revealed through feminity, sophistication, and harmony that are expressed with black and white colors, see-through material, or bead trimmings.

  • PDF

RC보의 부착보강공법과 외부강선보강공법의 유효응력에 관한 연구 (A Study on the Effective Stress of RC Beams in Applying the Adhesion Reinforced and the External Post-Tensioning Method)

  • 박용걸;최정열;최준혁
    • 한국철도학회논문집
    • /
    • 제10권2호
    • /
    • pp.186-194
    • /
    • 2007
  • This study was performed to compare the load-carrying capacities of the reinforced concrete structure between the carbon fiber adhesion reinforcement method and the external post-tensioning method and further estimate the effective stress of the reinforced material by analyzing the experimental reinforcing effect of each method and the behavior resulting from each method. As a result, it was found out that the effective stress of the carbon fiber reinforcement according to the carbon fiber adhesion reinforcement method had an unexpected value, and also, bearing of the stress was found to be far from sharing thereof. That is to say, while the carbon fiber was bearing the whole stress to some limits, it got to be momentarily ruptured as soon as it went beyond such limits. On the other hand, the external post-tensioning method has the advantage of inducing an initial effective stress by introducing a strain, and thus, it was found that behavior or bearing of the stress was also found to be a solid behavior of the steel wire. This method was also found to be more efficient and excellent than the carbon fiber adhesion reinforcement method in the reinforcing effect or securing the effective stress. Accordingly, we were to discuss the effective stress as comparatively examined, focusing on deriving of the more enhanced reinforcing effect on the basis of the experiment to which the field characteristic is added.

DEM 모델을 이용한 평판재하시험의 토양 수직응력 해석 (Soil Stress Analysis Using Discrete Element Method for Plate-Sinkage Tests)

  • 장기찬;이수진;이규진
    • 한국CDE학회논문집
    • /
    • 제20권3호
    • /
    • pp.230-237
    • /
    • 2015
  • Soil deformation on the off-load ground is significantly affected by soil conditions, such as soil type, water content, and etc. Thus, the soil characteristics should be estimated for predicting vehicle movements on the off-load conditions. The plate-sinkage test, a widely-used experimental test for predicting the wheel-soil interaction, provides the soil characteristic parameters from the relationship between soil stress and plate sinkage. In this study, soil stress under the plate-sinkage situation is calculated by the DEM (Discrete Element Method) model. We developed a virtual soil bin with DEM to obtain the vertical reaction forces under the plate pressing the soil surface. Also parametric studies to investigate effects of DEM model parameters, such as, particle density, Young's modulus, dynamic friction, rolling friction, and adhesion, on the characteristic soil parameters were performed.