• Title/Summary/Keyword: Mix characteristics

검색결과 728건 처리시간 1.239초

수지배합에 따른 GFRP 보강근의 인장 특성 (Tensile Properties of GFRP Rebars Based on Resin Mix Proportions)

  • 박지선;유영찬;박영환;유영준;김형열;김긍환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.561-564
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    • 2006
  • The tensile characteristics of four types GFRP (glass fiber reinforced polymer) reinforcing bars with different resin mix proportions and fiber volume fraction were analyzed experimentally. Four types of GFRP reinforcing bars containing approximately 66 or 70% fiber volume fraction with A or B rein mix proportions were considered in this test. All testing procedures including specimens preparation, set-up of test equipments and measuring devices were made according to the recommendations of CSA Standard S806-02. From the test results, it was found that GFRP reinforcing bars containing approximately 70% fiber volume fraction with A rein mix proportion showed the higher tensile strength than that of the others due to the higher fiber volume fraction and proper resin mix proportion.

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밀도와 흡수율을 고려한 제강슬래그 아스팔트 콘크리트의 배합설계 방법 연구 (A Study on a Steel Slag Asphalt Concrete Design Method Considering Density and Absorption)

  • 김경남;조신행;김낙석;김현욱
    • 한국도로학회논문집
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    • 제20권1호
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    • pp.59-67
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    • 2018
  • PURPOSES : This paper presents a mix design method for using steel slag as an aggregate for asphalt mixtures. METHODS : Steel slag has a different density and absorption rate than natural aggregates. The asphalt content was calculated according to the steel slag characteristics, and the formula for aggregate-gradation correction was presented. RESULTS : The asphalt mix was designed using the proposed equations. Using the proposed mix design method, it was possible to design the asphalt mixture according to the target-usage amount of the recycled aggregate. CONCLUSIONS : The suggested method can be used for asphalt mix design using aggregates with different densities and absorption rates. It is expected to contribute to quality improvement by ensuring accurate calculation of mixing ratios for steel slag asphalt mixtures.

F_MixBERT: Sentiment Analysis Model using Focal Loss for Imbalanced E-commerce Reviews

  • Fengqian Pang;Xi Chen;Letong Li;Xin Xu;Zhiqiang Xing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권2호
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    • pp.263-283
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    • 2024
  • Users' comments after online shopping are critical to product reputation and business improvement. These comments, sometimes known as e-commerce reviews, influence other customers' purchasing decisions. To confront large amounts of e-commerce reviews, automatic analysis based on machine learning and deep learning draws more and more attention. A core task therein is sentiment analysis. However, the e-commerce reviews exhibit the following characteristics: (1) inconsistency between comment content and the star rating; (2) a large number of unlabeled data, i.e., comments without a star rating, and (3) the data imbalance caused by the sparse negative comments. This paper employs Bidirectional Encoder Representation from Transformers (BERT), one of the best natural language processing models, as the base model. According to the above data characteristics, we propose the F_MixBERT framework, to more effectively use inconsistently low-quality and unlabeled data and resolve the problem of data imbalance. In the framework, the proposed MixBERT incorporates the MixMatch approach into BERT's high-dimensional vectors to train the unlabeled and low-quality data with generated pseudo labels. Meanwhile, data imbalance is resolved by Focal loss, which penalizes the contribution of large-scale data and easily-identifiable data to total loss. Comparative experiments demonstrate that the proposed framework outperforms BERT and MixBERT for sentiment analysis of e-commerce comments.

광물성 기포제를 이용한 경량기포콘크리트의 물리적성질에 관한 실험적 연구 (A Experimental Study on the Physical properties of Lightweight Foamed Concrete Using Mineral Foam Agent)

  • 유제준;이한승;배규웅;이상섭;연규봉
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2003년도 학술.기술논문 발표회
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    • pp.49-52
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    • 2003
  • The objective of this study the mechanical characteristics of prefoamed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/㎠ or more compressive strength, when was unit weight 0.8t/㎡. In the case of the same unit weight of concrete, it is influenced by w/c of foam agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufatured with the different factors in mix design and also present optimum mix proportion.

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광물성 기포제를 이용한 경량기포콘크리트의 물리적성질에 관한 실험적 연구 (A Experimental Study on the Physical properties of Lightweight Foamed Concrete Using Mineral Foam Agent)

  • 유제준;이한승;배규웅;이상섭;연규봉
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2003년도 학술.기술논문발표회
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    • pp.49.1-52
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    • 2003
  • The objective of this study the mechanical characteristics of preformed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/$\textrm{m}^3$ or more compressive strength, when was unit weight 0.8t/$\textrm{m}^3$. In the can of the same unit weight of concrete, it is influenced by w/c of loan agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufactured with the different factors in mix design and also present optimum mix proportion.

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Effects of Dietary Carbohydrases on Growth Performance, Nutrient Digestibility and Blood Characteristics in Finishing Pigs

  • Kim, Keun Hyoung;Cho, Jin Ho;Kim, In Ho
    • Journal of Animal Science and Technology
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    • 제55권4호
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    • pp.289-293
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    • 2013
  • The objective of this study was to assess the effects of dietary carbohydrases on growth performance, nutrient digestibility and blood characteristics in finishing pigs. A total of 90 pigs [(Landrace ${\times}$ Yorkshire) ${\times}$ Duroc] (initial BW = $56.15{\pm}1.26kg$) were used for a 35 d feeding trial. The dietary treatments included: 1) CON (control diet), 2) MIX (CON + mixture with ${\alpha}$-galactosidase and ${\beta}$-mannanase 0.05%) and 3) MAN (CON + ${\beta}$-mannanase 0.05%). There were six replications per treatment with five pigs per pen. The average daily gain (ADG) in MIX was higher than in CON (p<0.05). No significant differences were noted in the average daily feed intake (ADFI) and feed efficiency (G:F) among dietary treatments (p>0.05). Apparent total tract digestibility (ATTD) of dry matter (DM) and energy (E) in MIX increased (p<0.05) relative to CON and MAN. The ATTD of nitrogen (N) in MIX was higher (p<0.05) than in CON. No differences in red blood cells (RBC), white blood cells (WBC), lymphocytes and IgG concentrations were observed among dietary treatments (p>0.05). In conclusion, the addition of the mixture of carbohydrases (${\alpha}$-galactosidase and ${\beta}$-mannanase 0.05%) increased ADG and nutrient digestibility in finishing pigs.

Flexural performance and fiber distribution of an extruded DFRCC panel

  • Lee, Bang Yeon;Han, Byung-Chan;Cho, Chang-Geun;Kim, Yun Yong
    • Computers and Concrete
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    • 제10권2호
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    • pp.105-119
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    • 2012
  • This paper presents the mix composition and production method that was applied to an extruded Ductile Fiber Reinforced Cement Composite (DFRCC) panel, as well as the flexural performance, represented by deformation hardening behavior with multiple cracking. The effect of fiber distribution characteristics on the flexural behavior of the panel is also addressed. In order to demonstrate the fiber distribution effect, a series of experiments and analyses, including a sectional image analysis and micromechanical analysis, was performed. From the experimental and analysis results, it was found that the flexural behavior of the panel was highly affected by a slight variation in the mix composition. In terms of the average fiber orientation, the fiber distribution was found to be similar to that derived under the assumption of a two-dimensional random distribution, irrespective of the mix composition. In contrast, the probability density function for the fiber orientation was measured to vary depending on the mix composition.

Fractal equations to represent optimized grain size distributions used for concrete mix design

  • Sebsadji, Soumia K.;Chouicha, Kaddour
    • Computers and Concrete
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    • 제26권6호
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    • pp.505-513
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    • 2020
  • Grading of aggregate influences significantly almost all of the concrete performances. The purpose of this paper is to propose practicable equations that express the optimized total aggregate gradation, by weight or by number of particles in a concrete mix. The principle is based on the fractal feature of the grading of combined aggregate in a solid skeleton of concrete. Therefore, equations are derived based on the so-called fractal dimension of the grain size distribution of aggregates. Obtained model was then applied in such a way a correlation between some properties of the dry concrete mix and the fractal dimension of the aggregate gradation has been built. This demonstrates that the parameter fractal dimension is an efficacious tool to establish a unified model to study the solid phase of concrete in order to design aggregate gradation to meet certain requirements or even to predict some characteristics of the dry concrete mixture.

낙동강 세사를 사용한 콘크리트의 배합특성 평가 (Evaluation on Mix Characteristics of Concrete Using Fine Sand of Nakdong-River)

  • 배수호;김창덕;이승한
    • 한국산학기술학회논문지
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    • 제14권3호
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    • pp.1481-1488
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    • 2013
  • 지속적인 경제성장에 따른 콘크리트 구조물의 급증으로 양질의 하천모래가 고갈됨에 따라 콘크리트용 대체 골재 개발이 필요한 실정이다. 따라서 이 연구의 목적은 낙동강 세사를 콘크리트용 대체골재로서 적극적으로 활용하기 위한 기초자료를 제시하는 것이다. 이를 위하여 세사 분포지역인 낙동강 본류의 중 하류에서 세사 시료를 채취한 후, 이들의 밀도, 입도, 단위용적질량 및 0.08mm체 통과량 등의 물성 평가와 세사를 사용한 콘크리트의 배합특성으로 설계기준강도에 대한 단위수량 및 단위시멘트량을 평가하였다. 그 결과, 세사를 사용한 콘크리트의 설계기준강도에 대한 단위수량 및 단위시멘트량은 입도가 좋은 기준모래를 사용한 콘크리트의 경우보다 크게 증가하지 않는 것으로 나타나, 전자와 후자 사이의 배합특성은 별 차이가 없는 것으로 나타났다.

시대정신과 복식조형성과의 상관성(제1보) -르네상스와 포스틈던시대의 유사성을 중심으로- (Correlation between the Spirit of Times and Characteristics of Clothing -Similarity between Renaissance and Post-modern Period-)

  • 박숙현
    • 한국의류학회지
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    • 제25권4호
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    • pp.673-684
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    • 2001
  • The purpose of this study was to find out the correlation between the \"spirit of the times\" and the characteristics of each eras clothing in Renaissance and Post-modern Period. Theoretical studies about the \"spirit of times\" and the characteristics of clothing about each time were preceded. The results were as follows: Similarities of \"Spirit of times\" were 1) emphasis on humanity 2) anti-centralization 3) destruction of social status 4) deconstruction of christianity in Renaissance and modernism in Post-modern Period. Similarities of \"characteristics of clothing\" were 1) emphasis on erotic aspects of female body 2) emphasis of erotic aspects on clothing 3) tendency to revert to the old fashion 4) popularization of certain social groups fashion 5) tendency of deconstructionism in fashion 6) tendency of \"No match mix\" 7) androgynous style.f \"No match mix\" 7) androgynous style.ous style.

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