• Journal of the East Asian Society of Dietary Life
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• v.23 no.2
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• pp.218-226
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• 2013

This study examined the optimal mixture ratio of rice gruel supplemented with puffed rice by mixture design. The quality characteristics of rice gruel samples were examined according to mixture ratios at eleven experimental points. The high soluble solid content and viscosity of gruel samples were significantly dependent on rice (short grain) content instead of glutinous rice. The viscosity ranged from $2,891{\sim}9,153\;cP{\cdot}s$ and soluble solid content ranged from $8.23{\sim}10.13^{\circ}Brix$ at the eleven experimental points. The mixture with the highest solid content and viscosity, 12% rice gruel sample was $10.10{\sim}10.13^{\circ}Brix$ and $9,150{\sim}9,153\;cP{\cdot}s$. The L color of sample decreased with decreasing rice content, while "a" (redness) and "b" (yellowness) values slightly increased. In the sensory evaluation, samples with higher amount of puffed rice and glutinous rice scored higher for brown color, flavor and sweetness than high-content rice samples. The response surface and trace plot results showed that increasing of puffed rice increased the brown color, sweet taste and sticky aftertaste. From the results of the F-test, viscosity, "a" (redness) and "b" (yellowness) values fit a quadratic model with significant probabilities within 0.05%. The optimum predicted formulations of rice gruel containing puffed rice were 1.69% of puffed rice, 0.47% of glutinous rice and 9.84% of rice, respectively.

• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.153-159
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• 2005

This study is to choose the optimal mixture and to analyze the sensibility properties of High strength concrete and mass concrete to apply the high rising building. The main experimental variables were water/binder ratio $39\%,\;33\%,\;35\%\;and\;37\%$, replacement ratio of fly ash $5\%,\;10\%\;and\;15\%$, in the high strength concrete and water/binder ratio $39\%,\;41\%\;and\;43\%$, replacement ratio of fly ash $10\%,\;20\%\;and\;30\%$, in the man concrete. According to the test results, the principal conclusions are summarized as follows. 1) The slump(or slump flow) and air content of fresh concrete were found to be the highest in the elapsed time 30 minutes. 2) The optimal mixture conditions are W/B $40\%$, FA $25\%$ in the mass concrete and W/B $33.4\%$, FA $15\%$ in the high strength concrete. 3) The ranges of sensibility are satisfied in the moisture content ${\pm}l\%\;and\;S/a\;{\pm}2\%$.

• Computers and Concrete
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• v.17 no.5
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• pp.629-638
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• 2016

Optimization of the concrete mixture design is a process of search for a mixture for which the sum of the cost of the ingredients is the lowest, yet satisfying the required performance of concrete. In this study, a statistical model was carried out to model a cost effective optimal mix proportioning of high strength self-compacting concrete (HSSCC) using the Response Surface Methodology (RSM). The effect of five key mixture parameters such as water-binder ratio, cement content, fine aggregate percentage, fly ash content and superplasticizer content on the properties and performance of HSSCC like compressive strength, passing ability, segregation resistance and manufacturing cost were investigated. To demonstrate the responses of model in quadratic manner Central Composite Design (CCD) was chosen. The statistical model showed the adjusted correlation coefficient R2adj values were 92.55%, 93.49%, 92.33%, and 100% for each performance which establish the adequacy of the model. The optimum combination was determined to be $439.4kg/m^3$ cement content, 35.5% W/B ratio, 50.0% fine aggregate, $49.85kg/m^3$ fly ash, and $7.76kg/m^3$ superplasticizer within the interest region using desirability function. Finally, it is concluded that multiobjective optimization method based on desirability function of the proposed response model offers an efficient approach regarding the HSSCC mixture optimization.

• Geomechanics and Engineering
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• v.3 no.4
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• pp.267-284
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• 2011

The aim of the paper is to study the hydro-mechanical behaviour of a tuff and calcareous sand mixture. A first experimental phase was carried out in order to find the optimal mixture. This showed that the material composed of 80% tuff and 20% calcareous sand provides the maximum mechanical strength. The second experimental phase concerns the study of the drying- wetting behaviour of the optimal mixture. Triaxial shear tests in saturated and unsaturated states at constant water content were carried out on samples initially compacted at the MPO. Experimental results let to deduce the parameters necessary for the prediction of the hydro-mechanical behaviour of pavement formulated from tuff and calcareous sand mixtures, related to moisture. This optimal mixture satisfies the regulation rules and hence constitutes a good local eco-material, abundantly available, for the conception of pavements.

• International Journal of Highway Engineering
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• v.20 no.1
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• pp.69-76
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• 2018

PURPOSES : This study determined the optimal usage rate of RAP (reclaimed asphalt pavement) using cold central-plant recycling (CCPR) on a road-surface layer. In addition, a mixture-aggregate gradation design and a curing method based on the proposed rate for the surface-layer mix design were proposed. METHODS : First, current research trends were investigated by analyzing the optimum moisture content, mix design, and quality standards for surface layers in Korea and abroad. To analyze the aggregate characteristics of the RAP, its aggregate-size characteristics were analyzed through the combustion asphalt content test and the aggregate sieve analysis test. Moreover, aggregate-segregation experiments were performed to examine the possibility of RAP aggregate segregation from field compaction and vehicle traffic. After confirming the RAP quality standards, coarse aggregate and fine aggregate, aggregate-gradation design and quality tests were conducted for mixtures with 40% and 50% RAP usage. The optimum moisture content of the surface-layer mixture containing RAP was tested, as was the evapotranspiration effect on the surface-layer mixture of the optimum moisture content. RESULTS : After analyzing the RAP recycled aggregate size and extraction aggregate size, 13-8mm aggregate was found to be mostly 8mm aggregate after combustion. After using surface-chipping and mixing methods to examine the possibility of RAP aggregate segregation, it was found that the mixing method contributed very little for 3.32%, and because the surface-chipping method applied compaction energy directly as the maximum assumption the separation ratio was 15.46%. However, the composite aggregate gradation did not change. Using a 40% RAP aggregate rate on the surface-layer mixture for cold central-plant recycling satisfied the Abroad quality standard. The optimum moisture content of the surface-layer mixture was found to be 7.9% using the modified Marshall compaction test. It was found that the mixture was over 90% cured after curing at $60^{\circ}C$ for two days. CONCLUSIONS : To use the cold central-plant recycling mixture on a road-surface layer, a mixture-aggregate gradation design was proposed as the RAP recycled aggregate size without considering aggregate segregation, and the RAP optimal usage rate was 40%. In addition, the modified Marshall compaction test was used to determine the optimum moisture content as a mix-design parameter, and the curing method was adapted using the method recommended by Asphalt Recycling & Reclaiming Association (ARRA).

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.525-528
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• 2005

This study determines the best composite grade to minimize the void of aggregate mixture based on the maximum density theory in an attempt to suggest a mix proportion method design for asphalt mixtures. Study results show that the grading curve with the maximum mass per unit capacity of each aggregate mixture satisfied the KS standards and the optimum AP content to meet the optimal asphalt mixture void rate of 4$\%$ was 5.7$\%$, less than the optimum AP content of 6.5$\%$ suggested in the Marshal mix proportion method design. At the same time, the asphalt mixture produced based upon the suggested mix proportion method had a flow value 17$\%$ lower than that of asphalt mixture produced according to the Marshal method, while its density was greater by 0.06$\～$0.09. This suggests that the introduced mix proportion method design helps to improve the shape flexibility and crack-resistance of asphalt concrete.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.395-404
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• 2005

This study is to evaluate the physical and mechanical characteristics of flowable backfill and search for the optimal mixture contents of it used for constructing underground power utilities. flowable backfill is known as soil-cement slurry, void fill, and controlled low-strength material(CLSM). The benefits of CLSM include reduced equipment costs, faster construction, re-excavation in the future, and the ability to place material in confined spaces such as narrow parts nearly impossible for compaction or perimeter of underground power cables. The flowable slurry mixture made with 9 types of soil and 6 types of accelerated mixtures in the laboratory were evaluated for bleeding, flowability, heat resistance, and unconfined compressive strength to meet the aim values of this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.721-730
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• 2017

This study determined the optimal mixing ratio of functional materials to enhance the functionality of batter for fish cutlets. An optimal mixing ratio of the hiziki Hizikia fusiformis, fig fruit Ficus carica L. and pear Pyrus pyrifolia Niitaka extracts (HFP extract) of 3:1:1 was found. The physicochemical properties of the mixture were as follows: total phelonic contents of $1187.29{\pm}41.55mg/L$, 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging activity of $61.50{\pm}2.33%$, ascorbic acid content of $23.68{\pm}0.02g/100g$, ${\beta}-carotene$ content of $51{\pm}3.92{\mu}g/100g$, and sugar content of $12.7{\pm}0.1Brix^{\circ}$. A mixture of the extract, Korean herbal powder, and wheat flour was prepared as the fish cutlet batter. The fish cutlet prepared with the batter had a hardness of $166-202g/cm^2$ and Hunter's color scale values L of $31.14{\pm}2.1$ to $34.62{\pm}1.3$, a of $-4.89{\pm}0.21$ to $-2.26{\pm}0.19$ and b of $-20.65{\pm}2.65$ to $28.93{\pm}3.14$. The FRAP (ferric reducing antioxidant power) and VBN (volatile basic nitrogen) of the fish cutlets were measured to evaluate functionality and determine the optimal mixing ratio for cold storage at $-12^{\circ}C$, $-18^{\circ}C$, and $-24^{\circ}C$. The optimum mixture ratio of extracts /Korean herbal powder/ wheat flour was 1:6:3.

• Korean Journal of Food Science and Technology
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• v.53 no.2
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• pp.174-180
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• 2021

The optimal recipe for manufacturing composite honey-based herbal pills mainly comprising Rubus coreanus powder (RCP), black mulberry powder (BMP), and vitamin C was investigated. Honey-based herbal pills were prepared by mixing these powders, binding them with honey, and then forming a round shape. The experiment was designed based on the D-optimal mixture design, which included 12 experimental points with one replicate for three independent variables as follows: RCP (10~35%), BMP (10~35%), and vitamin C (5~10%). In addition, the dependent variables (total phenolic and flavonoid content and antioxidant activity) were measured and used to optimize the manufacturing conditions. The results showed that high amounts of RCP were correlated with high total flavonoid content, whereas the addition of high amounts of vitamin C resulted in higher antioxidant activity. In conclusion, an optimized formulation for the honey-based herbal pill was found to contain 35% RCP, 10% BMP, and 10% vitamin C.

• Journal of the Korean Society of Safety
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• v.25 no.3
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• pp.78-82
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• 2010

This study is to test insulation mortar mixed with wastepaper and sawdust to find out its insulation performance. Therefore, wastepaper and sawdust have been added to normal mortar. They are analyzed for the above purpose using compressive strength and insulation performance. It is found that the more wastepaper and sawdust will be mixed, the lower heat conductivity will be taken. Wastepaper and sawdust mixture will be more 2.0% then the insulation mortar quality can be compatible with the 3rd kind of the standard. Optimal mixture for insulation will be wast paper:sawdust=4:6. Cohesive test of materials showed that test material has stronger than stand are $0.10N/mm^2$. It is satisfactory the test result showed a range of $0.12{\sim}0.15N/mm^2$ from the test result. Optimal mixture of wastepaper and sawdust have been found out from the study comprehensively, exclusive of the proportion of wastepaper:sawdust = 8:2. It is thought that standard of length deformation; 0.5% is reasonable. This means that deformation of mortar itself can be considered. But it is also Shown that water mixture has also been sharply changed at first flow test. Therefore, it is thought that absorbed water content in the material gave considerable effect to variation rate.