• Title/Summary/Keyword: brush

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Semiflexible Polymer Brushes: Most Probable Configuration Approach Based on Cotinuous Chain Model

  • 김광규;차국헌
    • Bulletin of the Korean Chemical Society
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    • v.20 no.9
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    • pp.1026-1030
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    • 1999
  • The properties of semiflexible polymer brushes are studied by applying the classical limit of mean-field approach for chains with marginal chain stiffness. Using the mean-spherical Gaussian model, the most probable configuration for semiflexible chains is obtained, which reduces to the parabolic brush of Milner et al. [Mac-romolecules 1988, 21, 2610] in the flexible limit. From this configuration, equilibrium brush height as well as interactions between semiflexible brushes are estimated.

Comparison of Electricity Generation Efficiencies depending on the Reactor Configurations in Microbial Fuel Cells (미생물 연료 전지의 반응조 형상에 따른 전기 생산효율 비교)

  • Lee, Yunhee;Oa, Seong-Wook
    • Journal of Korean Society on Water Environment
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    • v.26 no.4
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    • pp.681-686
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    • 2010
  • Two different MFC designs were evaluated in batch mode: single compartment combined membrane-electrodes (SCME) design and twin-compartment brush-type anode electrodes (TBE) design (single chamber with two air cathodes and brush anodes at each side of the reactor). In SCME MFC, carbon anode and cathode electrodes were assembled with a proton exchange membrane (PEM). TBE MFC was consisted of brush-type anode and carbon cloth cathode electrodes without the PEM. A brush-type anode was fabricated with carbon fibers and was placed close to the cathode electrode to reduce the internal resistance. Substrates used in this study were glucose, leachate from cattle manure, or sucrose at different concentrations with phosphate buffer solution (PBS) of 200 mM to increase the conductivity thereby reduce the internal resistance. Hydrogen generating bacteria (HGB) were only inoculated in TBE MFC. The peak power densities ($P_{peak}$) produced from the SCME systems fed with glucose and leachate were 18.8 and $28.7mW/m^2$ at external loads of 1000 ohms, respectively. And the $P_{peak}$ produced from TBE MFC were 40.1 and $18.3mW/m^2$ at sucrose concentration of 5 g/L and external loads of 470 ohms, with a mediator (2-hydroxy-1, 4-naphthoquinone) and without the mediator, respectively. The maximum power density ($P_{max}$) produced from mediator present TBE MFC was $115.3mW/m^2$ at 47 ohms of an external resistor.

A Study on the Dynamic Painterly Stroke Generation for 3D Animation (3차원 애니메이션을 위한 회화적 스트로크의 동적 관리 기법)

  • Lee, Hyo-Keun;Ryoo, Seung-Taek;Yoon, Kyung-Hyun
    • Journal of Korea Multimedia Society
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    • v.8 no.4
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    • pp.554-568
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    • 2005
  • We suggest the dynamic stroke generation algorithm that provides frame-to-frame coherence in 3D non-photorealistic animations. We use 3D particle system to eliminate the visual popping effect in the animated scene. Since we have located particles on the 3D object's surface, the coherence is maintained when the object or the camera is moving in the scene. Also, this algorithm maintains the coherence when camera is zooming in/out. However, the brush strokes on the surface also zoom in/out. This result(too large or too small brush strokes) can not represent hand-crafted brush strokes. To remove this problem, we suggest stroke generation algorithm that dynamically maintains the number of brush stroke and its size during camera zoom in/out.

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A Study on Wear-Life Prediction of Conductor Roll Polisher in EGL Polishing Process (EGL 공정용 컨덕터 롤 폴리셔 수명 예측에 관한 연구)

  • Ku, Ja-Kyung;Ko, Jong-Min;Ku, Tae-Wan;Kang, Beom-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.9
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    • pp.1062-1069
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    • 2011
  • In electro-galvanizing line to manufacture the electro-galvanized steel sheet, polishing system is required to maintain clean surface of conductor roll and to secure the quality of the steel sheet. At the same time, prediction and decision of the replacement cycle for felt material and its brush installed in the polishing system is also important because the brush is directly contacted on the conductor roll surface. In this study, the polishing system has been designed which the brush is repetitive translating according to the longitudinal direction of the conductor roll. Furthermore, the prediction on the wear-life of the felt material used for the brush is performed using the contact pressure extracted by finite element analysis. And to verify the predicted wear-life of the felt material, the experimental study is also carried out. From the comparison result between the predicted and the measured wear-life of the felt material, it is presented that the wear-life and the replacement cycle of the felt material are well predicted by considering a wear compensation factor, and the wear compensation factor is useful and reasonable.

Painterly rendering using density of edges (에지 밀도 정보를 이용한 회화적 렌더링)

  • Lee, Ho-Chang;Park, Young-Sup;Seo, Sang-Hyun;Yoon, Kyung-Hyn
    • Journal of the Korea Computer Graphics Society
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    • v.12 no.4
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    • pp.7-15
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    • 2006
  • The ultimate objective of painterly rendering is to express an inputted image as if it is hand drawn. The factors to express this painterly effect are thickness of the brush, direction, texture and the establishment of criteria judging if the produced brush will be drawn on to the canvas. In this paper, the algorithm using density of the edges in determining the criteria whether the brush will be drawn onto the canvas is proposed. Density of edges refers to the quantity of edge in the specific area. And uses the method of finding the location of the brush to be drawn as a unit of dynamic grid as well as expressing consistent directional through direction interpolation. Also, the texture is expressed using various textured brushes. Considering density of edges,We can express detailed area and abstract area. And it result in more human effect of oil painting.

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Motion Areas based Painterly Animation using Various Edges (다양한 에지를 이용한 모션영역 기반 회화적 애니메이션)

  • Park, Young-Sup;Yoon, Kyung-Hyun
    • Journal of the Korea Computer Graphics Society
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    • v.14 no.1
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    • pp.1-10
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    • 2008
  • In this paper, we present a novel method for creating a hand-painted painterly animation, starting from a video input. One of the most important aspects in painterly animation is to maintain the temporal coherence of brush strokes between frames, which plays a vital role to warrant a smooth transition between frames. Our unique utilization of motion areas enables users to produce a smooth movement of brush strokes. The motion areas are the parts where objects move between frames and they are categorized in two main types. A strong motion area is the part where the movement of real edges and hidden edges is determined by the motion vector between frames. The real edge is the outline of an object and the hidden edge is the boundary to represent the direction of a grain of intensity in the areas with gradations. A weak motion area is the remainder after subtracting the strong motion area from the entire motion area. Temporally coherent painterly animation is achieved by re-painting the brush strokes on the canvas using two motion areas, resulting in a natural and hand-painted appearance.

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Structural design method of the steel brush type loading platen adopted in multi-axial compression experiments (다축압축 실험에 적용되는 철제 빗살구조 재하판의 구조 설계 기법)

  • SaGong, Myung;Lee, Jun-S.;Kim, Sung-Soo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.9 no.4
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    • pp.351-359
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    • 2007
  • Multi-axial compression tests have been frequently conducted to evaluate the in situ properties of rock masses and the mechanical behaviors of rock strata through the model tests. Without the proper boundary condition for the model tests, the mechanical behavior of rock mass would deviate, as can be expected, from the in situ conditions. The boundary condition will affect the internal stress distribution of the specimens and cause some distortion on the measurement. In this study, a design process regarding the steel brush, which has been employed for multi-axial compression test to reduce the frictional restraint along the specimen/loading platen interface, is introduced. The individual brushes are regarded as a simple column and beam to calculate the cross-sectional size and length of the brushes in consideration of the buckling capacity and the allowable deflection.

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Influencing factors to dental caries and periodontal diseases in Korean adults (성인의 치아우식증 및 치주질환에 영향을 미치는 요인)

  • Jung, Yu-Jin;Cho, Mi-Hyang;Moon, Deog-Hwan
    • Journal of Korean society of Dental Hygiene
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    • v.15 no.1
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    • pp.47-54
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    • 2015
  • Objectives: The aim of this study was to investigate the factors related to dental caries and periodontal disease in Korean adults. Methods: The subjects were 5,149 adults over 19 years old who participated in the 5th Korea National Health and Nutrition Examination Survey 2012. Data were analyzed by chi-square test and logistic regression analysis using SPSS 18.0 statistical package program. The questionnaire consisted of 17 questions of independent variables and 2 kinds of dependent variables including dental caries and periodontal diseases by direct interview. The independent variables included 5 questions of general characteristics, 3 questions of health behavior, 5 questions of oral health behavior, and 4 questions of chronic diseases diagnosed by the doctors. Results: The prevalence rate of dental caries was higher in those who did not regularly work out and did not receive regular checkups including dental floss and dental brush use. The prevalence rate of periodontal diseases was higher in male adults, smokers, and those who were obese and had diabetes mellitus, poor oral health care habit without using dental floss and inter-dental brush. Conclusions: In order to prevent the dental caries in the adults, it is very important to do regular exercise and regular dental checkup. The best ways of dental caries prevention include tooth brushing after meal with use of dental floss and inter-dental brush. This study suggests that dental health promotion can be enhanced by smoking cessation, ideal body weight maintenance, timely tooth brushing after meal, and use of dental floss and inter-dental brush.

Changes in Phosphate Transporter Activity Evaluated by Phosphonoformic Acid Binding in Cadmium-Exposed Renal Brush-Border Membranes

  • Chung, Jin-Mo;Ahn, Do-Whan;Kim, Kyoung-Ryong;Park, Yang-Saeng
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.5
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    • pp.513-519
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    • 1999
  • Direct exposure of renal tubular brush-border membranes (BBM) to free cadmium (Cd) causes a reduction in phosphate (Pi) transport capacity. Biochemical mechanism of this reduction was investigated in the present study. Renal proximal tubular brush-border membrane vesicles (BBMV) were isolated from rabbit kidney outer cortex by Mg precipitation method. Vesicles were exposed to $50{\sim}200\;{\mu}M\;CdCl_2$ for 30 min, then the phosphate transporter activity was determined. The range of Cd concentration employed in this study was comparable to that of the unbound Cd documented in renal cortical tissues of Cd-exposed animals at the time of onset of renal dysfunction. The rate of sodium-dependent phosphate transport $(Na^+-Pi\;cotransport)$ by BBMV was determined by $^{32}P-Iabeled$ inorganic phosphate uptake, and the number of $Na^+-Pi$ cotransporters in the BBM was assessed by Pi-protectable $^{14}C-labeled$ phosphonoformic acid $([^{14}C]PFA)$ binding. The exposure of BBMV to Cd decreased the $Na^+-Pi$ cotransport activity in proportion to the Cd concentration in the preincubation medium, but it showed no apparent effect on the Pi-protectable PFA binding. These results indicate that an interaction of renal BBM with free Cd induces a reduction in $Na^+-Pi$ cotransport activity without altering the carrier density in the membrane. This, in turn, suggest that the suppression of phosphate transport capacity $(V_{max})$ observed in Cd-treated renal BBM is due to a reduction in $Na^+-Pi$ translocation by existing carriers, possibly by Cd-induced fall in membrane fluidity.

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A pilot study of a new fingerprint powder application method for the reduction of health risk

  • Kim, Eun-Ji;Lee, Da-Eun;Park, Suk-Won;Seo, Kyung-Suk;Choi, Sung-Woon
    • Analytical Science and Technology
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    • v.32 no.5
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    • pp.196-209
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    • 2019
  • As a traditional method to apply fingerprint powder, brush method ("dusting") can create a risk to the health of crime scene investigators due to the inhalation toxicity of harmful and fine powders. Therefore, as a new method of applying powders, we tried to evaluate the potential of a chamber method for the development of latent fingerprint using fans in a closed chamber with a fixed capacity that can prevent the powders from being blown outside and exposed to the users, by comparing with the development results of the conventional brush method. Fingerprints on glass and plastic (PET) were extracted with black powder and green fluorescent powder, and the sharpness and minutiae of the developed fingerprints were compared for each method. The results of the black powder showed similar results, but the effect of the chamber method was slightly decreased when the green fluorescent powder was used. In order to improve the development with the green fluorescent powder, the mixture (50 : 50) of the fluorescent powder with the silica gel was tested and the results were similar to those of the brush method. It is expected that the chamber method has a high potential as a new powder application method considering the health of the crime scene investigator after fine tuning of development conditions with additional studies.