• 제목/요약/키워드: Surface smoothness

검색결과 172건 처리시간 0.027초

양모 복지의 초기열류속최대치($q_{max}$)에 관한 연구(II) -직물 표면 형태 인자와의 상관성을 중심으로 - (A Study on the Initial Maximum Value of Heat Flux, $q_{max}$ of Wool Fabrics (Part II) - The correlation between $q_{max}$ and chracteristic values -)

  • 최석철;정진순;천태일
    • 한국의류학회지
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    • 제15권4호
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    • pp.373-380
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    • 1991
  • In the previous paper, we already discussed about the factor effected upon the initial maximum value of heat flux ($q_{max}$). Thermal conductivity, thermal transmittance and surface air cavity of wool fabrics were examind and their correlation to the $q_{max}$ was also studied In this study, the other factor was examined which had on effect upon the qmaf of an objective measure of warm/cool feeling. It was studied that the qmax correlated to the surface sturucture parameters (compression, friction, smoothness, roughness, thickness and weight). It was concerned to the degree of warm/cool feeling when we touched hand on fabrics. We selected twenty sorts of pure wool woven fabrics for men's fall-winter cloth (all Wool). The conclusions are as follow; 1. There was a good correlation between the $q_{max}$ and the compression property. 2. The surface structure parameters, smoothness and roughness, made various effects on the $q_{max}$, when the samples touched on a thin copper plate. So, there was not a certain correla-tion to the $q_{max}$.

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SEM과 AFM을 사용한 반도전 재료 내 카본블랙의 형태 및 분산성 측정 (Formation and Dispersion Measurement in Semiconducting Materials Using the SEM and AFM)

  • 이경용;양종석;남종철;최용성;박동하;박대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.236-237
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    • 2005
  • To measure surface roughness and smoothness of semiconducting materials in power cable, we have investigated the formation and growth process of carbon black showed by changing the content of carbon black. The specimens were primarily kneaded in material samples of pellet form for 5 minutes on rollers ranging between 70[$^{\circ}C$] and 100[$^{\circ}C$]. Then they were produced as sheets after pressing for 20 minutes at 180[$^{\circ}C$] with a pressure of 200[kg/cm]. The contents of conductive carbon black were the variable, and their contents were 20, 30 and 40[wt%], respectively. The surface roughness and smoothness of specimens were measured by SEM and AFM. From SEM experimental result, carbon black in specimens formed matrix as a particles. Also we showed growth process of carbon black according to an increment of the content of carbon black. From AFM experimental result, surface roughness of specimens decreased according to an increment of the content of carbon black.

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표면강도 향상제 내첨에 따른 수초지 특성 변화 (Handsheet Property Changes by Internal Addition of Surface Strength Agent)

  • 임종혁;정철헌;채희재;박창순;박종문
    • 펄프종이기술
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    • 제42권2호
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    • pp.41-45
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    • 2010
  • This study was performed to evaluate the effect of paper property changes by internal addition of surface strength agent on printability. Advances in printing technique has required the development of paper qualities in many aspects. Basically paper structure is composed of hydrogen bonds which induce many problems in high speed printing machine because of weak bonding strength. One of the important printing problems is surface picking when mechanical pulp or recycled pulp are used. It was caused by the ink-stained blanket in printing process because accumulations of pollutant in white water and other elements which are bonded weakly or do not have hydrogen bonds. Debris at paper surface adheres to blanket which deteriorates printing efficiency and causes various problems. To complement these problems, Pennocel 5137 of polysaccharide structure was used as an agent to improve paper's surface property, strength and printability. Paper surface picking was analyzed by RI-1 test. As the dosage amount increased tensile strength, fiber bonding strength and ZDT strength were improved. Further more formation, smoothness and surface picking resistance were improved. It was confirmed that when adding polysaccharide structure polymers to improve surface strength such as surface picking resistance, it was also possible to improve tensile strength, fiber bonding strength, formation and smoothness.

진공소성도재에 사용되는 glazing과 staining에 관한 실험적 연구 (An experimetal study on staining and glazing of vacumn-fired porcelain)

  • 조성암
    • 대한치과보철학회지
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    • 제22권1호
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    • pp.69-71
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    • 1984
  • The surface smoothness of dental porelain after the use of various staining and glazing technique was examined by scanning electron microscopy. 1. Autogenous self-glazing technique produced a most rough surface. 2. The fixation of stain at $1,500^{\circ}F$ followed by thin slurry of glaze powder air fired to $1,800^{\circ}F$ produce the most smooth surface. 3. The technique thin sluny of glare powder followed by slurry of stain powder air fired to $1,800^{\circ}F$ produce the poor result.

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스테인레스강 차체의 제작 관련 문제 및 대책에 관한 연구 (A Study on the correction of production related problems in stainless steel rolling stocks)

  • 서승일
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.826-831
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    • 2004
  • In this study. problems caused during production process of stainless steel carbody are investigated and solutions are found out. Roll forming process to make complex shape is introduced and surface crack on high strength stainless steel plate is investigated. Also, surface indentation is discussed and the effect of welding condition is clarified. Insulated tip to reduce the indentation is recommended for improvement of surface smoothness. Lastly. corrosion of welded joint is discussed and the effects of material, stress and environment are investigated.

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도로포장 표면평탄성에 따른 주행차량의 동적 하중 변화 특성 (Variation of Moving Dynamic Vehicle Loads According to Surface Smoothness of Pavement Systems)

  • 김성민;이석근
    • 한국도로학회논문집
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    • 제10권1호
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    • pp.135-144
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    • 2008
  • 주행하는 차량이 도로포장에 가하는 동적 하중은 포장표면의 거칠기에 따라 그 크기가 변화하게 되며 설계하중보다 큰 하중이 재하 될 경우에는 포장의 공용성에 영향을 미치게 된다. 따라서 본 논문에서는 포장표면의 평탄성에 대한 지불규정을 시방에 적용하여 포장의 성능 및 품질향상을 도모하기 위한 기본연구로써 도로포장의 표면에 거칠기가 있을 때 주행차량에 의한 동적 하중 크기의 변화를 분석하였다. 먼저 평탄성이 좋지 않은 오래된 포장과 평탄성이 좋은 새로운 포장에서 구한 평탄성 데이터를 이용하여 구조해석을 수행함으로써 이러한 포장에서 차량이 주행할 때 동적 하중의 크기 변화를 비교 분석하였다. 그리고 차량속도와 표면 거칠기의 진폭 및 파장이 차량 동적 하중 크기에 미치는 영향을 가상의 평탄성 데이터를 구성하여 분석하였다. 이러한 표면 거칠기에 의한 동적 차량하중 크기의 증가는 포장의 응력 및 변형률에 영향을 미치며 궁극적으로 포장의 공용성과 연관되기 때문에 표면 거칠기와 포장의 공용성과의 관계를 유출하는 방법을 제시하였다

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금합금 연마재 종류에 따른 금합금 소실량과 연마 정도 (THE AMOUT OF LOSS AND THE DEGREE OF SURFACE SMOOTHNESS OF GOLD ALLOY BY GOLD ALLOY POLISHING RUBBER POINT MATERIALS)

  • 김명화;임순호;정문규
    • 대한치과보철학회지
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    • 제35권2호
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    • pp.277-295
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    • 1997
  • After clinical adjustment of dental casting restoration, re-polishing procedure is recommanded because the smooth gold sureface is lost. But there is the possibility to get more loose contact than that intended by loss of gold alloy according to the kinds of polishing materials and polishing time. Therefore in this study I polished type II gold alloy with 390gm force, 20,000rpm speed, and 8 kinds of gold alloy polishing materials, fabricated by 4 companies and then measured the amount of loss of gold alloy with Surfcorder SEF-30D and observed alloy surfaces polished by 3 brown rubber points with SEM. The amount of loss of gold alloys polished with 8 kinds of polishing materials and the degree of smoothness of gold alloys according to polishing time and polishing materials were compared. The following results were obtained : 1. When the amount of loss of gold alloys polished with 3 kinds of brown rubber point was compared, Alphalex brown point had the most amount of alloy loss, followed in decreasing order by Shofu brown point and Eveflex brown point. There was statistically significant difference in the amount of alloy loss according to polishing materials. 2. When the amount of loss of gold alloys polished with 5 kinds of green rubber point was compared, Shofu green point had the most amount of alloy loss, followed in decreasing order by Alphaflex green point, Dedeco green clasp polisher, and Eveflex green point. There was statistically significant difference in the amount of alloy loss according to polishing materials except Alphaflex green point and Dedeco green clasp polisher. 3. When the amount of loss of gold alloys polished with all kinds of rubber point was compared, there was no significant difference in Eveflex brown point, Alphaflex green point, and Dedeco green clasp polisher. 4. When average amount of alloy loss per 1 revolution by polishing materials was compared, Alphalex brown point had the greatest value as $0.329{\mu}m$ and Shofu supergreen point had the lowest value as $0.022{\mu}m$. 5. When the degree of sureface smoothness of gold alloy polished with 3 kinds of brown rubber point was compared, In Alphalex brown point surface roughness was completely lost after 20 seconds polishing time, in Shofu brown point 30 seconds, in Eveflex brown point 40 seconds. But in every gold alloys fine scratch formed by rubber points was observed. Based on the results of this study, as rubber polishing materials used in polishing of dental casting restoration after clinical adjustment influenced on the tightness of occlusal or proximal contact, we should make dental casting restoration with minimum error through careful laboratory procedure and form very smooth surface of restoration with tripoli and rouge after use of silicone polishing materials.

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단시안 명암강도를 이용한 물체의 3차원 거리측정 (Obtaining 3-D Depth from a Monochrome Shaded Image)

  • Byung Il Kim
    • 전자공학회논문지B
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    • 제29B권7호
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    • pp.52-61
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    • 1992
  • 본 논문은 단시안에 투영된 3차원 물체의 Image에서 측정된 명암강도의 차이를 이용하여 3차원 물체의 절대거리 z 및 형상을 유출하는 수치적인 방법을 연구, 단시안에 의해서도 Camera와 물체사이의 3차원 절대거리가 구해질 수 있음을 보여주고 있다. 기발표된 이론과는 다르게 본 논문에서는 점광원을 이용하여 투영된 명암강도와 3차원 물체의 절대거리 및 형상과의 관계를 물체가 Uniform Lambertian이라는 가정하에서 새로운 관계식으로 정립하였다. 정립된 Non-Linear 관계식은 Smoothness 조건아래 $'Calculus of Variation$'방법을 사용하여 수학적 Algorithm으로 정리되어 Programming 되었고 간단한 실험방법을 이용하여 실제 Data에 적용시켜 그 타당성을 조사하였다.당성을 조사하였다.

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CONSTRUCTIVE WAVELET COEFFICIENTS MEASURING SMOOTHNESS THROUGH BOX SPLINES

  • Kim, Dai-Gyoung
    • 대한수학회지
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    • 제33권4호
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    • pp.955-982
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    • 1996
  • In surface compression applications, one of the main issues is how to efficiently store and calculate the computer representation of certain surfaces. This leads us to consider a nonlinear approximation by box splines with free knots since, for instance, the nonlinear method based on wavelet decomposition gives efficient compression and recovery algorithms for such surfaces (cf. [12]).

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신문용지의 소프트닙 캘린더링 특성 평가 (Evaluation of Soft Nip Calendering Characteristics of Newsprints)

  • 문성호;이학래
    • 펄프종이기술
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    • 제32권2호
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    • pp.16-25
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    • 2000
  • The influence of four process parameters of soft nip calendering including calendering pressure, temperature, moisture content and nip residence time on bulk, smoothness and tensile strength of newsprints has been investigated. In addition, the effect of basis weights on calendering responses has been examined. Bulk of newsprints decreased and smoothness increased with the increase of the calendering pressure, temperature, moisture content of the sheets and nip residence time. Improvement in tensile strength was observed when low calendering pressure and high temperature of heat-ing roll were employed. Tensile strength of the newsprint, however, decreased abruptly when the calendering temperature and pressure increased above certain levels due to the rupture of sheet structure, which has been verified by SEM. SEM micrographs also showed that it would be possible to maintain the inner bulk while densifying the fibers on the outer surface of newsprint by adjusting the soft nip calendering variables properly.

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