• Computers and Concrete
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• 제29권3호
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• pp.169-186
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• 2022

Mortar is produced with different degrees of temperature and ratios of admixture materials. In order to produce strength mortar, the degree of temperature and the ratio of admixture materials must be optimized. This paper examines experimental effects by applying certain degrees of temperature and ratios of admixture materials to statistically understand the changes in the strength of mortar. The Taguchi method is used for the above-mentioned optimization problem. Firstly, factorial ANOVA is used to investigate the difference of means between the experiments. Due to the significant differences in obtained means, the regression analysis is applied. On the other hand, the effects of the varying degrees of temperature and admixture ratios are presented via 3D plots. Finally, the statistical results of ANOVA and Taguchi indicate that degree of temperature and the different ratios of admixture materials can affect the behaviour of mortar under the tests.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.183-188
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• 2002

When Concrete work during winter is placed, it has anxiety that concrete freeze at low temperature. As concrete's freezing cause reduction of durability, it is necessary for mixing to pay attention to Air content and W/C ratios. Accordingly, in this study, we set up three series and evaluate a frost-resistance of concrete with admixture, like fly-ash and blast-furnace slag, for early curing method and types of chemical admixture..The study is composed as; I series : Analysis for early curing method and types of chemical admixture in laboratory II series : Analysis for early curing method and types of chemical admixture in batcher plant and measured concrete' temperature. The result of this study, it was more effective the use of super-plasticizers than air entraining agent.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8호
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• pp.1069-1076
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• 2019

Objective: Yunnan is not only a frontier zone that connects China with South and Southeast Asia, but also represents an admixture zone between taurine (Bos taurus) and zebu (Bos indicus) cattle. The purpose of this study is to understand the level of genomic diversity and the extent of admixture in each Yunnan native cattle breed. Methods: All 120 individuals were genotyped using Illumina BovineHD BeadChip (777,962 single nucleotide polymorphisms [SNPs]). Quality control and genomic diversity indexes were calculated using PLINK software. The principal component analysis (PCA) was assessed using SMARTPCA program implemented in EIGENSOFT software. The ADMIXTURE software was used to reveal admixture patterns among breeds. Results: A total of 604,630 SNPs was obtained after quality control procedures. Among six breeds, the highest level of mean heterozygosity was found in Zhaotong cattle from Northeastern Yunnan, whereas the lowest level of heterozygosity was detected in Dehong humped cattle from Western Yunnan. The PCA based on a pruned dataset of 233,788 SNPs clearly separated Dehong humped cattle (supposed to be a pure zebu breed) from other five breeds. The admixture analysis further revealed two clusters (K = 2 with the lowest cross validation error), corresponding to taurine and zebu cattle lineages. All six breeds except for Dehong humped cattle showed different degrees of admixture between taurine and zebu cattle. As expected, Dehong humped cattle showed no signature of taurine cattle influence. Conclusion: Overall, considerable genomic diversity was found in six Yunnan native cattle breeds except for Dehong humped cattle from Western Yunnan. Dehong humped cattle is a pure zebu breed, while other five breeds had admixed origins with different extents of admixture between taurine and zebu cattle. Such admixture by crossbreeding between zebu and taurine cattle facilitated the spread of zebu cattle from tropical and subtropical regions to other highland regions in Yunnan.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.178-179
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• 2019

The purpose of this study was to investigate the possibility as mineral admixture of agriculture by-product. XRD and XRF analysis were performed on rice straw ashes at various combustion temperatures to identify chemical compositions. Also to evaluate properties of pozzolanic reaction, pH change method was tested.

• 대한건축학회연합논문집
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• 제21권5호
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• pp.117-124
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• 2019

When manufacturing concrete, several mineral admixture is added to improve the basic physical property and durability and to make economical concrete. Such mineral admixture includes fly ash, granulated blast furnace slag, silica fume, etc., and not only the studies about mixing these mineral admixtures but also the studies for the development of new materials have been steadily in progress. Recently, some researchers have found, as a part of the development of new materials, the rice straw ash can also be used as a pozzolanic material for concrete considering similar chemical properties of rice straw ash to that of rice husk ash. But there has been insufficient amount of study about it. So, this study was to investigate the possibility as mineral admixture of agriculture by-product, by analyzing properties of concretes using rice straw ash with replacement ratio in comparison with other mineral admixture. In order to measure amount of SiO2 of rice straw ash, XRF(X-ray fluorescence) analysis was tested. For the measure pozzolanic reaction of rice straw ash, pH change and color change was tested according to curing day. Also to evaluate properties of concrete using rice straw ash, slump test, air contents test and compressive strength was tested.

• Asian-Australasian Journal of Animal Sciences
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• 제18권5호
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• pp.613-619
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• 2005

Indigenous Yakutian cattle' adaptation to the hardest subarctic conditions makes them a valuable genetic resource for cattle breeding in the Siberian area. Since early last century, crossbreeding between native Yakutian cattle and imported Simmental and Kholmogory breeds has been widely adopted. In this study, variations at 22 polymorphic microsatellite loci in 5 populations of Yakutian, Kholmogory, Simmental, Yakutian-Kholmogory and Yakutian-Simmental cattle were analysed to estimate the genetic contribution of Yakutian cattle to the two hybrid populations. Three statistical approaches were used: the weighted least-squares (WLS) method which considers all allele frequencies; a recently developed implementation of a Markov chain Monte Carlo (MCMC) method called likelihood-based estimation of admixture (LEA); and a model-based Bayesian admixture analysis method (STRUCTURE). At population-level admixture analyses, the estimate based on the LEA was consistent with that obtained by the WLS method. Both methods showed that the genetic contribution of the indigenous Yakutian cattle in Yakutian-Kholmogory was small (9.6% by the LEA and 14.2% by the WLS method). In the Yakutian-Simmental population, the genetic contribution of the indigenous Yakutian cattle was considerably higher (62.8% by the LEA and 56.9% by the WLS method). Individual-level admixture analyses using STRUCTURE proved to be more informative than the multidimensional scaling analysis (MDSA) based on individual-based genetic distances. Of the 9 Yakutian-Simmental animals studied, 8 showed admixed origin, whereas of the 14 studied Yakutian-Kholmogory animals only 2 showed Yakutian ancestry (>5%). The mean posterior distributions of individual admixture coefficient (q) varied greatly among the samples in both hybrid populations. This study revealed a minor existing contribution of the Yakutian cattle in the Yakutian-Kholmogory hybrid population, but in the Yakutian-Simmental hybrid population, a major genetic contribution of the Yakutian cattle was seen. The results reflect the different crossbreeding patterns used in the development of the two hybrid populations. Additionally, molecular evidence for differences among individual admixture proportions was seen in both hybrid populations, resulting from the stochastic process in crossing over generations.

• Computers and Concrete
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• 제12권5호
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• pp.613-625
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• 2013

In this study, Artificial Neural Networks (ANN) analysis is used to predict the compression strength of polypropylene fibre mixed concrete. Polypropylene fibre admixture increases the compression strength of concrete to a certain extent according to mix proportion. This proportion and homogenous distribution are important parameters on compression strength. Determination of compression strength of fibre mixed concrete is significant due to the veridicality of capacity calculations. Plenty of experiments shall be completed to state the compression strength of concrete which have different fibre admixture. In each case, it is known that performing the laboratory experiments is costly and time-consuming. Therefore, ANN analysis is used to predict the 7 and 28 days of compression strength values. For this purpose, 156 test specimens are produced that have 26 different types of fibre admixture. While the results of 120 specimens are used for training process, 36 of them are separated for test process in ANN analysis to determine the validity of experimental results. Finally, it is seen that ANN analysis predicts the compression strength of concrete successfully.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2002년도 학술논문발표회
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• pp.85-90
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• 2002

This study aims to propose a fundamental report for pozzolan reaction of discarded Bentonite by heat-treatment as concrete mineral admixture. As discarded bentonite is clay mineral to contain a great quantity a lot of $SiO_2$ and $Al_{2}O_{3}$, it is anticipated to reveal pozzolan reaction ability by heat-treatment. To find out pozzolan reaction ability of discarded Bentonite slurry by heat-treatment, the experiment is excuted Phenolphtalein test, setting test, pH test and the analysis by X-ray diffractor. As a result of this study, discarded Bentonite slurry can be utilized as concrete mineral admixture by heat-treatment and especially, pozzolan reaction ability of discarded Bentonite slurry is superior to the situation of 50$0^{\circ}C$~$700^{\circ}C$, 60min.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.63-65
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• 2010

The purpose of the study was to analyze dry shrinkage of HVFAC (high volume fly ash concrete) with admixture to improve early strength. The results were as follows. In dry shrinkage of HVFAC with admixture to improve early strength, F3 had the lowest amount of dry shrinkage. The next is in order of Plain, F3-f15 and F3-f15r5. The study used index function modelfor analysis on dry shrinkage. Coefficient of determination was more than 0.97 in all mix, which made it possible to have a good estimation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.101-102
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• 2019

The use of high fluidity concrete has been added in recent construction work. In this study, we analyzed segregation resistance due to admixture substitution of the system high fluidity concrete that was hardened. The research results show that the resistance to segregation at the time of admixture replacement is improved. The best results were shown with a ternary system mixed like FA and BS.