• Title/Summary/Keyword: Surface Character

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The Prediction of Rubber Friction considering Road Characteristics (노면 특성을 고려한 고무 마찰 예측 연구)

  • Nam, Seungkuk;Oh, Yumrak;Jeon, Seonghee
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.4
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    • pp.105-110
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    • 2014
  • This paper presents the hysteresis friction of a sliding elastomer on various types of surfaces. The hysteresis friction is calculated by means of an analytical model which considers the energy spent by the local deformation of the rubber due to surface asperities. By establishing the fractal character of the surfaces, the contribution to rubber friction of roughness at different length scales is accounted for. High resolution surface profilometer is used in order to calculate the main three surface descriptors and the minimal length scale that can contribute to hysteresis friction. The results show that this friction prediction can be used in order to characterize in an elegant manner the surface morphology of various surfaces and to quantify the friction coefficient of sliding rubber as a function of surface roughness, load and speed.

Presentation and Representation of Modernity in Modern Architecture - On Exclusion of Ornament and Emergence of the surface - (근대주의 건축에서 모더니티 표상의 문제 - 장식의 배제와 표면의 부각을 중심으로 -)

  • Khang, Hyuk
    • Journal of architectural history
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    • v.15 no.4
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    • pp.37-56
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    • 2006
  • Introducing International Style, P. Johnson and H. R. Hitchcock gave three standards to be the Modern, volume and surface, regularity, and exclusion of applied decoration. In spite of the negation of stylistic, formal approach in the Modernist Manifestoes, one usually have understood Modernity in Architecture with its formal character, especially with no ornament and flat, abstract, white surface. Modernism as a new paradigm in architecture have emphasized that there is no representation of anything outside and only present architecture in itself. They said that Modernism only cared about the language of Architecture without figural reference. So apparently there is no way to prove to its Modernity with formal condition. Modernity is in Spirit and contents. But actually we understand well its existence by visual communication This study deals with this difficult situation how Modernity represents itself without visual media and asks the question how simultaneously it presents its thingness and materiality In order to analyse contradictory situation between representation and presentation in Modern Architecture we need to survey the historical process of changing position of ornaments and its meaning in time. With the crisis of representation the role of ornament have seriously changed and divided. It caused the two situation in pre-Modern Architecture. Firstly, Architecture tend to be a high art and formal expression became important much more. The Use of Ornament became a kind of fashion to show the power, class, money. Secondly, Ornament lost its cultural weight and the structure and material aspect became the central in architecture. Rational Structuralism would be the essential character in Modern Architecture. Here the theory of G. Semper and A. Loos on cladding(dressing) and Ornament can help its problems and limits. In the situation without conventional ornament Modernists need to present modernity with new media that only show the thing itself and by that it does not represent any thing else as like the value, idea outside buildings. They believed that only it concerned esthetics and morality in architecture. But in reality it referred to art and machines as like ships, aircraft, and cars. By excluding Ornament and showing the process of clearing, abstract, flat, white surface 'represent' Modernity by the indirect way referring the concept of transparency, reason, sanitation, tectonics, etc. An Ideology and myth intervened architectural discourse to make the doxa about the representation in Architecture. Surface must be a different kind of media and message that can communicate in different way with compared to conventional Ornament. Decorated Shed by R. Venturi and Post-Functionalism by P. Eisenman, that are the most famous post-modern discourse, shows well difficult and contradictory condition in contemporary architecture concerning representation and form, meaning and form.

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Effects of the Surface Roughness of a Graphite Substrate on the Interlayer Surface Roughness of Deposited SiC Layer (SiC 증착층 계면의 표면조도에 미치는 흑연 기판의 표면조도 영향)

  • Park, Ji Yeon;Jeong, Myung Hoon;Kim, Daejong;Kim, Weon-Ju
    • Journal of the Korean Ceramic Society
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    • v.50 no.2
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    • pp.122-126
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    • 2013
  • The surface roughness of the inner and outer surfaces of a tube is an important requirement for nuclear fuel cladding. When an inner SiC clad tube, which is considered as an advanced Pressurized Water Cooled Reactor (PWR) clad with a three-layered structure, is fabricated by Chemical Vapor Deposition (CVD), the surface roughness of the substrate, graphite, is an important process parameter. The surface character of the graphite substrate could directly affect the roughness of the inner surface of SiC deposits, which is in contact with a substrate. To evaluate the effects of the surface roughness changes of a substrate, SiC deposits were fabricated using different types of graphite substrates prepared by the following four polishing paths and heat-treatment for purification: (1) polishing with #220 abrasive paper (PP) without heat treatment (HT), (2) polishing with #220 PP with HT, (3) #2400 PP without HT, (4) polishing with #2400 PP with HT. The average surface roughnesses (Ra) of each deposited SiC layer are 4.273, 6.599, 3.069, and $6.401{\mu}m$, respectively. In the low pressure SiC CVD process with a graphite substrate, the removal of graphite particles on the graphite surface during the purification and the temperature increasing process for CVD seemed to affect the surface roughness of SiC deposits. For the lower surface roughness of the as-deposited interlayer of SiC on the graphite substrate, the fine controlled processing with the completed removal of rough scratches and cleaning at each polishing and heat treating step was important.

Surface Electrical Conduction Properties of Composite Insulator Materials (옥외 애자용 재료의 표면 전기 전도 특성)

  • Hong, Hyun-Mun;Jeon, B.S.;Kim, J.G.;Kang, S.H.
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.05a
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    • pp.409-411
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    • 2005
  • In this literature, we mose the design method of a proportional pressure control valve using valve system analysis and finite element method. And it is shown that a manufactured proportional pressure control valve character is well matched to tile theoretical analysis results. Also it is verified that the proposed valve has excellent performance compared to the other foreign products.

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A Study on the Tendency of Deconstructivism in Interior Design (실내디자인의 해체주의적 구성 경향에 관한 연구)

  • 윤도근;김홍기
    • Korean Institute of Interior Design Journal
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    • no.1
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    • pp.22-25
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    • 1992
  • The purpose of this study is to understand spatial composition techniques and character on the tendency of Deconstructivisim in interior design. Interior space is basically surrounded by architectural surface and influenced by architectural shape. Therefore, the main point of this study is based on the inter relationship of interior design and the trend of contemporary architectural design. This viewpoint is to comment upon current events in Korean situation some degree, but allow the new feeling to interior design and can be enlarge the concepts of spatial composition.

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A Study of The Wearable Input Device Based on Human Hand-Motions Recognition

  • Daehui Won;Lee, Hogil;Kim, Jinyoung
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.51.5-51
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    • 2002
  • In this paper, we propose and developed a keyglove using the touch-typing method as new solutions to the problem of text input into the mobile computing devices. This device recognizes that character is typed in though the hand's movements analysis and requires no additional space on a person's desktop or work surface, and can be easily used with computers of any size, even the smallest mobile computer, and is designed as an input device for wearable computers and virtual environment. The concept of the wearable input device based on human hand-molies recognition.

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Segmentation and estimation of surfaces from statistical probability of texture features

  • Terauchi, Mutsuhiro;Nagamachi, Mitsuo;Koji-Ito;Tsuji, Toshio
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10b
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    • pp.826-831
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    • 1988
  • This paper presents an approach to segment an image into areas of surfaces, and to compute the surface properties from a gray-scale image in order to describe the surfaces for reconstruction of the 3-D shape of the objects. In general, an rigid body has several surfaces and many edges. But if it is not polyhedoron, it is necessary not only to describe the relation between surfaces, i.e. its line drawings but also to represent the surfaces' equations itself. In order to compute the surfaces' equation we use a probability of edge distribution. At first it is extracted edges from a gray-level image as much as possible. These are not only the points that maximize the change of an image intensuty but candidates which can be seemed to be edges. Next, other character of a surface (color, coordinates and image intensity) are extracted. In our study, we call the all feature of a surface as "texture", for example color, intensity level, orientation of an edge, shape of a surface and so on. These features of a surface on a pixel of an image plane are mapped to a point of the feature space, and segmented to each groups by cluster analysis on this space. These groups are considered to represent object surface in an image plane. Finally, the states of object surface in 3-D space are computed from distributional probability of local and overall statistical features of a surface, and from shape of a surface.a surface.

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Adsorption properties of activated carbon prepared from pre-carbonized petroleum coke in the removal of organic pollutants from aqueous solution

  • Ahmed, S.A. Sayed;El-Enin, Reham M.M. Abo;El-Nabarawy, Th.
    • Carbon letters
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    • v.12 no.3
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    • pp.152-161
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    • 2011
  • Activated carbon was prepared from pre-carbonized petroleum coke. Textural properties were determined from studies of the adsorption of nitrogen at 77 K and the surface chemistry was obtained using the Fourier-transform infrared spectrometer technique and the Boehm titration process. The adsorption of three aromatic compounds, namely phenol (P), p-nitrophenol (PNP) and benzoic acid (BA) onto APC in aqueous solution was studied in a batch system with respect to contact time, pH, initial concentration of solutes and temperature. Active carbon APC obtained was found to possess a high surface area and a predominantly microporous structure; it also had an acidic surface character. The experimental data fitted the pseudo-second-order kinetic model well; also, the intraparticle diffusion was the only controlling process in determining the adsorption of the three pollutants investigated. The adsorption data fit well with the Langmuir and Freundlich models. The uptake of the three pollutants was found to be strongly dependent on the pH value and the temperature of the solution. Most of the experiments were conducted at pH 7; the $pH_{(PZC)}$ of the active carbon under study was 5.0; the surface of the active carbon was negatively charged. The thermodynamic parameters evaluated for APC revealed that the adsorption of P was spontaneous and exothermic in nature, while PNP and BA showed no-spontaneity of the adsorption process and that process was endothermic in nature.

Palynological contributions to the taxonomy of family Oleaceae, with special empahsis on genus Forsythia (tribe Forsytheae)

  • Lee, Sangtae
    • Korean Journal of Plant Taxonomy
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    • v.41 no.3
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    • pp.175-181
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    • 2011
  • Traditionally, the Oleaceae has been divided into subfamilies Oleoideae and Jasminoideae. In the present paper, the taxonomical results so far made on the family were reviewed on the basis of palynology. The subfamilial classification is not well supported palynoligically, because both Myxopyrum of Jasminoideae and Comoranthus of Oleoideae having foveolate surface are well distinguished from the rest of the family having reticulate surface. The recent subfamily Nyctanthoideae (Takhtajan, 1977) including the monotypic Nyctanthus, was suggested to be included within the Jasminoideae although its closest relative on the palynological basis is different from that on the molecular basis. Tribal classification systems of the Jasminoideae are not well supported palynologically on the basis of surface character: presence or absence of bands on the mural ridge surface of the reticulum. On the basis of palynology, tribe Forsythiae including Abeliophyllum, Fontanesia, and Forsythia is monophyletic, and Fontanesia is well distinguished from the rest two. Korean species of Forsythia is divided into two: Forsythia koreana group and F. ovata-nakaii-saxatilis group. Recent discovery of F. saxatilis at a locality of F. ovata raised a question if the distinction between the two species on the basis of hairiness would be right. In the recent molecular studies, F. saxatilis var. lanceolata seems to be identified as F. saxatilis. Molecular studies showed that F. saxatilis (seemingly var. lanceolata or var. pilosa) is close to F. koreana. The fact in which the molecular result showed a close relationship between F. saxatilis varieties and F. koreana, is controversial to the result by floral and vegetative morphology. An intensive taxonomic study of these taxa would be needed.

Seafloor Morphology and Surface Sediment Distribution of the Southwestern Part of the Ulleung Basin, East Sea (동해 울릉분지 남서부 해저지형 및 표층퇴적물 분포)

  • Koo, Bon-Young;Kim, Seong-Pil;Lee, Gwang-Soo;Chung, Gong Soo
    • Journal of the Korean earth science society
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    • v.35 no.2
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    • pp.131-146
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    • 2014
  • Multi-beam echosounder data and grain size analysis data of surface sediment were acquired and analyzed in order to investigate the shelf-to-slope morphology, geological character, and their geological controlling factors in the southwestern margin of the Ulleung Basin. According to the morphological character, the continental shelf can be divided into two parts: (1) shallow (~100 m) and steep ($0.5^{\circ}$) inner shelf, (2) deep (100-300 m) and gentle ($0.2^{\circ}$) outer shelf. The continental slope is featured with eight distinct topographic depressions of various spatial dimension (~121 $km^2$ in area) and head wall gradient (${\sim}24.3^{\circ}$). They are developed adjacent to each other and presumably formed by submarine landslides which have recurred under the strong influences of earthquakes and eustatic sea-level change. The inner continental shelf and the continental slope are dominated by fine-grained sediment, whereas the outer continental shelf is dominated by coarse-grained sediment. The surface sediment distribution seems dominantly influenced by eustatic sea-level change. The outer continental shelf is mostly covered by coarse relict sediment deposited during lowstand sea-level, while the inner shelf is covered with recent sediment during highstand sea-level. The surface of the continental slope is covered with fine-grained sediments which were supplied by hemipelagic advection process.