• 제목/요약/키워드: ratios and proportions

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Proportions of the aesthetic African-Caribbean face: idealized ratios, comparison with the golden proportion and perceptions of attractiveness

  • Mantelakis, Angelos;Iosifidis, Michalis;Al-Bitar, Zaid B.;Antoniadis, Vyron;Wertheim, David;Garagiola, Umberto;Naini, Farhad B.
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제40권
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    • pp.20.1-20.10
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    • 2018
  • Background: In the absence of clear guidelines for facial aesthetic surgery, most surgeons rely on expert intuitive judgement when planning aesthetic and reconstructive surgery. One of the most famous theories regarding "ideal" facial proportions is that of the golden proportion. However, there are conflicting opinions as to whether it can be used to assess facial attractiveness. The aim of this investigation was to assess facial ratios of professional black models and to compare the ratios with the golden proportion. Methods: Forty photographs of male and female professional black models were collected. Observers were asked to assign a score from 1 to 10 (1 = not very attractive, 10 = very attractive). A total of 287 responses were analysed for grading behaviour according to various demographic factors by two groups of observers. The best graded photographs were compared with the least well-graded photographs to identify any differences in their facial ratios. The models' facial ratios were calculated and compared with the golden proportion. Results: Differences in grading behaviour were observed amongst the two assessment groups. Only one out of the 12 facial ratios was not significantly different from the golden proportion. Conclusions: Only one facial ratio was observed to be similar to the golden proportion in professional model facial photographs. No correlation was found between facial ratios in professional black models with the golden proportion. It is proposed that an individualistic treatment for each ratio is a rather better method to guide future practice.

Symmetry, ratio and proportion in Scottish clan tartans - Templates for modern designers -

  • Hann, Michael;Wang, Chaoran
    • 복식문화연구
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    • 제24권6호
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    • pp.873-885
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    • 2016
  • It is common knowledge that a conventionally woven textile consists of two assemblies of parallel threads (warp and weft), one interlaced with the other at ninety degrees. Where each of the two assemblies is arranged in a particular colour sequence, a check design, known as a 'tartan', may be created. Although similar check-type cloths have been produced worldwide, it is the tartans of Scotland which have received most attention and it is here that a complex set of rules evolved and tartans of different types became associated traditionally with different regions, family groups or 'clans'. There is an impressive array of publications focused on the identification of tartans and their clan associations. This paper explains the nature of tartans, analyses typical surface structures, ratios and proportions, and suggests possible avenues of use for modern designers. The principal sources of data were a collection of tartans held at ULITA - An Archive of International Textiles (University of Leeds, UK) and Stewart's 1974 publication The Setts of Scottish Tartans. Based on the observation that divisions into halfs and thirds were dominant, a series of templates is presented with the intention of developing an awareness among designers that ratios and proportions used in familiar or traditional frameworks can be employed in a modern context.

폴리머 시멘트 콘크리트의 배합조건이 투수성능과 역학적 성질에 미치는 영향 (Effect of Mix Proportions on the Permeability and Mechanical Properties of Polymer Cement Concrete)

  • 박응모;조영국;소양섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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    • pp.356-361
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    • 1998
  • Permeable polymer cement concrete in this study is one of the invironment conscious concretes that can be applied at roads, side walks, parking lots, interlocking block and river embankment, etc. In this study, permeable polymer cement concretes using polymer dispersion(St/Ac) with water-cement ratios of 25, 30, 35 and 40%, polymer-cement ratios of 0, 5, 10, 15 and 20%, and a ratio of cement to aggregate (by weight), 1 : 3.5(about 415kg/㎥), 1 : 4.0(about 375 kg/㎥), and 1 : 4.5(about 345kg/㎥) are prepared, and tested for compressive, flexural and tensile strength, and permeability. From the test results, increase in the strengths of permeable polymer cement concrete are clearly observed with increasing polymer-cement ratio, we can obtain the maximum strengths at water-cement ratio of 35%. The optimum permeable polymer cement concrete according to application and location of work can be selected in various mix proportions.

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St/BA 폴리머 시멘트 모르타르의 물리적 특성 및 내구성 (Physical Properties and Durability of Polymer Modified Mortar Using Styrene and Butyl Acrylate Latexes)

  • 형원길
    • 폴리머
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    • 제33권4호
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    • pp.342-346
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    • 2009
  • 본 연구에서는 스티렌(styrene; St)과 부틸아크릴레이트(butyl acrylate; BA)를 단량체 비에 따라 합성 제조하고, 합성제조된 시멘트 혼화용 폴리머를 혼입한 폴리머 시멘트 모르타르의 물리적 성질과 내구성에 대한 특성을 보통 시멘트 모르타르와 기존에 생산되어 현장에 적용되고 있는 St/BA계 폴리머 시멘트 모르타르를 비교 분석하고자 하였다. 실험결과, St/BA의 단량체 비가 50:50, 60:40일 경우에는 시멘트 혼화용으로 사용하기에 가장 적합하였으며, 강도특성에서도 우수한 결과를 나타냈다. 또한, 방수성능과 염화물 이온에 대한 침투 저항성, 그리고 중성화 저항성도 St/BA의 단량체 비가 증가할수록, 폴리머 시멘트 비가 증가할수록 증진효과가 우수한 결과를 나타냈다. 따라서, 본 연구를 통해 합성제조된 St/BA 라텍스를 시멘트 모르타르에 혼입할 경우 우수한 성능개선 효과를 얻을 수 있었다.

보수재료로서 수중불분리 폴리머 시멘트 모르타르의 기초적 배합 (Basic Mix Proportions of Antiwashout Underwater Polymer Cement Mortar as a Repair Material)

  • 조영국
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.193-194
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    • 2019
  • The purpose of this study is to design the basic mix proportions of antiwashout underwater polymer cement mortar as a repair material. The antiwashout underwater polymer cement mortars are prepared with various mix proportions using three type polymer dispersions without or with antifoamer. From the test results, the whole antiwashout underwater polymer cement mortars can be cast underwater without segregation like plain mortar. It is apparent that the flexural strength of antiwashout underwater SBR cement mortars with antifoamer at polymer- cement ratios of 5% and 10% is higher than that of plain mortar irregardless of a little low compressive strength.

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St/BA의 모노머 비에 따른 폴리머 시멘트 모르타르 개발에 관한 연구 (A Study on the Development of Polymer-Modified Mortars Using Styrene-Butyl Acrylate Latexes)

  • 형원길;문경주;송훈
    • 콘크리트학회논문집
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    • 제18권6호
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    • pp.785-791
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    • 2006
  • 본 연구에서는 스틸렌(styrene)과 부틸아크릴레이트(butyl acrylate)를 모노머 비에 따라 합성 제조하고, 합성 제조 된 시멘트 혼화용 폴리머를 혼입한 폴리머 시멘트 모르타르의 물리적 성질과 내구성에 대한 특성을 보통 시멘트 모르타르와 기존에 생산되어 현장에 적용되고 있는 St/BA계 폴리머 시멘트 모르타르를 비교 분석하고자 하였다. 실험 결과, St/BA의 모노머 비가 50:50, 60:40일 경우에는 시멘트 혼화용으로 사용하기에 가장 적합하였으며, 세공용적의 분포나 강도 특성에서도 우수한 결과를 나타냈다. 또한 방수성능과 염화물 이온에 대한 침투 저항성도 St/BA의 모노머비가 증가할수록, 폴리머 시멘트 비가 증가할수록 증진 효과가 우수한 결과를 나타냈다. 따라서 본 연구를 통해 합성제조된 St/BA 라텍스를 시멘트 모르타르에 혼입할 경우 우수한 성능개선 효과를 얻을 수 있었다.

건유기 유방염 감염우의 유방내 면역저하요인 규명에 관한 연구 I. 유방염 감염우와 정상우의 말초혈액 및 유즙내 림프구 아집단 분포율 비교 (Characterization of immunosuppressive factors in the mastitis-infected mammary gland of non-lactating cows I. Comparison of proportion of lymphocyte subpopulations from peripheral blood and mammary gland secretions of normal healthy cows and mastitic cows)

  • 신동백;박용호;남향미;문진산;주이석;신종욱
    • 대한수의학회지
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    • 제36권3호
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    • pp.635-646
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    • 1996
  • To establish the effective ways to prevent bovine mastitis, the study has been performed to investigate the attributable factors causing down-regulation of immune responses in mammary gland of non-lactating cows. Lymphocytes from peripheral blood and mammary gland secretions(MGS) were obtained from normal healthy cows and mastitic cows, respectively. Cellular immune responses were examined by comparison of proportion of lymphocyte subpopulations using a set of monoclonal antibodies and flow cytometry. The results obtained are as follows. 1. Proportions of peripheral blood lymphocyte subpopulations expressing BoCD2 and BoCD4 molecules were 32.9%, 15.4% in mastitic cows and 43.3%, 28.3% in normal healthy cows, respectively. The ratios of BoCD4 to BoCD8 were 0.76 and 1.47, respectively. 2. Proportions of mammary gland lymphocyte subpopulations expressing BoCD2 and BoCD4 molecules were 18.5%, 8.3% in mastitic cows and 38.2%, 14.2% in normal healthy cows, respectively. The ratios of BoCD4 to BoCD8 were 0.6 and 2.0, respectively. 3. Proportions of T lymphocyte subpopulations from MGS were significantly lower than those from peripheral blood both in mastitic cows and normal healthy cows. However, lymphocyte subpopulations expressing ACT2 and ACT3, which represent activated T suppressor cells, were significantly higher in MGS than those in peripheral blood.

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순환굵은골재, 황토, 고로슬래그 미분말 및 마섬유를 사용한 레인가든 구조물 콘크리트의 최적배합설계 및 역학적 특성 (Optimum Mix Proportion and Mechanical Properties of Rain Garden Structure Concrete using Recycled Coarse Aggregate, Hwang-Toh, Blast Furnace Slag and Jute Fiber)

  • 김동현;박찬기
    • 한국농공학회논문집
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    • 제55권3호
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    • pp.25-33
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    • 2013
  • In this study, the optimum mix proportions of rain garden structure concrete were decided and the mechanical properties were evaluated. Experimental parameters were blast furnace slag, hwang-toh, recycled aggregates and natural jute fibers. The target compressive strength and chloride ion penetration were more than 24 MPa and less than 1000 coulombs, respectively. The response surface method was used for statistical optimization of experimental results. The optimal mixing ratios of the blast furnace slag, hwang-toh, recycled coarse aggregate and jute fiber volume fraction were determined 59.98 %, 8.74 %, 12.12 % and 0.2 %, respectively. The compressive strength, flexural strength and chloride ion penetration test results of optimum mix ratio showed that the 24.56 MPa, 3.88 MPa and 999.08 columbs, respectively.

쿤-터커 조건을 이용한 건물의 에너지성능과 비용 최적화방법 (Optimization Method of Building Energy Performance and Construction Cost Using Kuhn-Tucker Conditions)

  • 원종서;구재오
    • KIEAE Journal
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    • 제3권2호
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    • pp.51-58
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    • 2003
  • The purpose of this study is to present rational methods of multi-criteria optimization of the shape of energy saving buildings. The object is to determine the optimum dimension of the shape of a building, based on the following criteria: minimum building costs (including the cost of materials and construction) and yearly heating costs. Mathematical model described heat losses and gains in a building during the heating season. It takes into consideration heat losses through wall, roof, floor and windows. Particular attention was paid to have a more detailed description of heat gains due to solar radiation. On the assumption that shape of building is rectangle in order to solve the problem, the proportions of wall length and building height are determined by using non-linear programing methods(Kuhn-Tucker Conditions). The results constitute information for designers on the optimum proportions of wall lengths, height, and the ratios of window to wall areas for energy saving buildings.

Prediction of compressive strength of slag concrete using a blended cement hydration model

  • Wang, Xiao-Yong;Lee, Han-Seung
    • Computers and Concrete
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    • 제14권3호
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    • pp.247-262
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    • 2014
  • Partial replacement of Portland cement by slag can reduce the energy consumption and $CO_2$ emission therefore is beneficial to circular economy and sustainable development. Compressive strength is the most important engineering property of concrete. This paper presents a numerical procedure to predict the development of compressive strength of slag blended concrete. This numerical procedure starts with a kinetic hydration model for cement-slag blends by considering the production of calcium hydroxide in cement hydration and its consumption in slag reactions. Reaction degrees of cement slag are obtained as accompanied results from the hydration model. Gel-space ratio of hardening slag blended concrete is determined using reaction degrees of cement and slag, mixing proportions of concrete, and volume stoichiometries of cement hydration and slag reaction. Furthermore, the development of compressive strength is evaluated through Powers' gel-space ratio theory considering the contributions of cement hydration and slag reaction. The proposed model is verified through experimental data on concrete with different water-to-binder ratios and slag substitution ratios.