• International Journal of Highway Engineering
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• v.17 no.6
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• pp.1-9
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• 2015

PURPOSES : The objective of this study is to propose a quality control and quality assurance method for use during asphalt pavement construction using non-destructive methods, such as ground penetrating radar (GPR) and an infrared (IR) camera. METHODS : A 1.0 GHz air-coupled GPR system was used to measure the thickness and in situ density of asphalt concrete overlay during the placement and compaction of the asphalt layer in two test construction sections. The in situ density of the asphalt layer was estimated based on the dielectric constant of the asphalt concrete, which was measured as the ratio of the amplitude of the surface reflection of the asphalt mat to that of a metal plate. In addition, an IR camera was used to monitor the surface temperature of the asphalt mat to ensure its uniformity, for both conventional asphalt concrete and fiber-reinforced asphalt (FRA) concrete. RESULTS : From the GPR test, the measured in situ air void of the asphalt concrete overlay gradually decreased from 12.6% at placement to 8.1% after five roller passes for conventional asphalt concrete, and from 10.7% to 5.9% for the FRA concrete. The thickness of the asphalt concrete overlay was reduced from 7.0 cm to 6.0 cm for the conventional material, and from 9.2 cm to 6.4 cm for the FRA concrete. From the IR camera measurements, the temperature differences in the asphalt mat ranged from $10^{\circ}C$ to $30^{\circ}C$ in the two test sections. CONCLUSIONS : During asphalt concrete construction, GPR and IR tests can be applicable for monitoring the changes in in situ density, thickness, and temperature differences of the overlay, which are the most important factors for quality control. For easier and more reliable quality control of asphalt overlay construction, it is better to use the thickness measurement from the GPR.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.193-203
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• 2006

The quality characteristics of cookies containing black rice flour, which has a greater variety of functional components than wheat flour, were studied. The results of the pasting properties shows that the inclusion of black rice flour to the wheat flour-mixture did not affect the pasting temperature but increased the enthalpy, indicating that more energy is needed for the starch gelatinization. The total dietary fiber and total polyphenol content increased and the cookies color became darker and deeper with increasing black rice flour content. According to the results from TA on texture, the hardness decreased and the crispness increased significantly (both, p<0.001) with increasing black rice flour content. From the acceptance test, the appearance, aroma and texture of the cookies with added black rice flour were significantly (p<0.001) lower than those of the wheat flour cookies. However, the taste and overall acceptance of the cookies with added black rice (lour did not differ significantly from those of the wheat flour cookies. According to the results from the sensory evaluation, the aroma, black rice flavor, crispness, graininess and color(gray-violet) of the cookies increased significantly(p<0.001) with increasing black rice flour content and those of the cookies with 30% black rice flour had the highest values among the cookies which weren't significantly different from those of the cookies with 20% black rice flour. From the above results, the optimal ratio for the addition of black rice flour to the cookies was 10% from the viewpoint of the sensory evaluation and functional components.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.365-371
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• 2019

In this study, the flame temperature distribution of the diffusion flame burner for SiO₂ deposition was analyzed by the computational fluid analysis. This corresponds to the previous step for simulating the SiO₂ preform deposition process for manufacturing optical fibers using environmentally friendly raw materials. In order to model premixed combustion, heat flow, convection, and chemical reactions were considered, and Reynolds-averaged Navier-Stokes equations and k-ω models were used. As a result, the temperature distribution of the flame showed a tendency to increase the distance from the nozzle surface to the maximum temperature when the flow rate of the auxiliary oxygen increased. In addition, it was confirmed that the temperature distribution due to incomplete combustion was large in the combustion reaction with a large equivalence ratio of the mixed gas.

• Nutrition Research and Practice
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• v.8 no.4
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• pp.410-416
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• 2014

BACKGROUND/OBJECTIVES: The standard pattern of Brazilian food consumption is based on the combination of rice and beans served together in the main meals. This study assessed the effects of Brazilian-staple calorie-restricted (BS-diet) dietary advice, with brown rice and beans, on metabolic parameters, body composition, and food intake in overweight/obese subjects. SUBJECTS/METHODS: Twentyseven subjects were randomly assigned to a conventional-type calorie-restricted diet (CT-diet) (n = 13) or a BS-diet (n = 14). Glucose metabolism, lipid profile, anthropometric and body composition parameters, and food intake were measured before and after 16 weeks. Paired t-tests/Wilcoxon tests were used for comparison of differences from baseline and unpaired t-tests/Mann-Whitney tests were used for comparison of differences between the groups. RESULTS: After16 weeks, both groups showed reductions in weight and waist circumference (P < 0.02), and the BS-diet group showed a decrease in body fat (P = 0.0001), and significant improvement in glucose metabolism (fasting plasma glucose, glucose and insulin areas under the curve, Cederholm index, and HOMA2-$%{\beta}$) ($P{\leq}0.04$) and lipid profile (cholesterol, triacylglycerol, LDL-c, VLDL-c, and cholesterol/HDL-c ratio) ($P{\leq}0.05$). In addition, the BS-diet group showed significant improvement in HOMA2-$%{\beta}$, compared to the CT-diet group (P = 0.03). The BS-diet group also showed a significant reduction in energy, lipids, carbohydrate, and cholesterol intake ($P{\leq}0.04$) and an increase in fiber intake ($P{\leq}0.001$), while the CT-diet group showed a significant reduction in intake of energy, macronutrients, PUFA, and cholesterol ($P{\leq}0.002$). CONCLUSIONS: These results demonstrate the benefits of the BS-diet on metabolic parameters in obese subjects.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.370-378
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• 2017

Objective: An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods: Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results: Ruminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion:The results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.337-342
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• 2004

A non-ionic surfactant, Tween 80 has been known to exert a number of positive effects on degradative enzymes in in vitro aerobic and anaerobic microbial cultures. An experiment was conducted to examine effects of supplementation of Tween 80 on ruminal fermentation and nutrient digestibility of Hanwoo steers. The experiment was designed as a $3{\times}3$ Latin square with duplication and six Hanwoo steers with rumen cannulae, average weight 497 (SE 61.1) kg. For the experiment the animals were given a basal diet consisting of rice straw and compound feed mixed at 4:6 ratio. The three experimental treatments were (1) the basal diet, supplemented with (2) 5 g/d Tween 80 and (3) 10 g/d Tween 80. Ruminal pH was significantly (p<0.05) affected by Tween 80 supplementation at 6 h after feeding. Increasing supplementation levels of Tween 80 linearly increased the total VFA concentration. CMCase activity by the 10g/d supplementation of Tween 80 were significantly increased (p<0.05) by 24.4% compared with that of control. Digestibility of crude fiber was significantly increased (p<0.05) in Hanwoo steers fed the diet supplemented with 10 g/d Tween 80 compared with those of control, whilst digestibility of ether extract (EE) was linearly increased by increasing Tween 80 supplementation level (p<0.05). In other nutrient components, their digestibilities of Hanwoo fed diets supplemented with Tween 80 tended to increase. It is concluded that Tween 80 has a potential for industrial application as a feed additive to improve ruminant production.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.63-71
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• 2015

The objective of the present study is to investigate how elevated temperature ranging from $100^{\circ}C$ to $800^{\circ}C$ as well as room temperature affects the variation of mechanical properties of high strength concrete ($over\;f_{ck}=60MPa\;grade$). In this experiment, specimens were exposed for a period of $2^{\circ}C/min$ to temperatures of $20^{\circ}C$, $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$ $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, $700^{\circ}C$ and $800^{\circ}C$, respectively. Accordingly, the study investigated the fire resistance performance of high strength concrete mixed with composite fibers which composed with hybrid fibers and steel fibers. After cooling down to ambient temperature, the following basic mechanical properties were then evaluated and compared with reference values obtained prior to thermal exposure: (i) compressive strength in room temperature; (ii) residual compressive strength; (iii) Poisson's ratio; (iv) weight change; (v) SEM analysis & XRD analysis In addition, XRD and SEM Images analyses were performed to investigate chemical and physical characteristics of high strength concrete with composite fibers according to high temperature.

• Composites Research
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• v.12 no.2
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• pp.91-100
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• 1999

The manufacture of high strength polyethylene(HSPE) tape yarns has been accomplished by a solid state processing(SSP) method as the compaction of ultra-high molecular weight polyethylene(UHMWPE) powders and drawing of the compacted film under the melting point without any organic solvents. In this study, the characteristics of HSPE tape yarns produced by SSP which is desirable for production cost and environmental aspect were analyzed. As the results, tensile strengths of HSPE tape yarns increased with increasing the draw ratio and the fracture morphology of highly drawn HSPE tape yarns showed more fibrillar shape than the low drawn one. Interfacial shear strengths of HSPE tape yarns with vinylester resin increased by $O_2$ plasma treatment and maximum interfacial shear strength was obtained in the plasma treatment condition of 100W and 5min. In addition, mechanical properties of HSPE tape yarn reinforced composites were investigated and compared with those of the gel spun HSPE fiber reinforced composites.

• Magazine of the Korea Concrete Institute
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• v.7 no.5
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• pp.179-188
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• 1995

SFRC overcomes brittleness of concrete and has increases strength due to the action of confmement, crack arrestmg mechan~sm and pull out resistances of steel f~bers ~ n s ~ d e the concrete. These lead also to the increased strength and ductility under the shear stress. It has been reported that the secondary remforcement effect of steel fibers IS more pronounced In shear than flexure. Addition of hooked stee!, fibers into the cementitious materials enhanced shear resistance and consequently improves structural behavior and shear strength of Reinforced Hooked-Steel-Fiber Concrete Ream(RHSFCI3) under the shear forces. Experimental observations were made on the main parameters effecting structural behavior of RHSFCB in this study. The volume fractions of fibers, shear span to depth ratios, and spaclngs of stlrrups were taken into account as the mam parameters. Some eyuatlons reported in the literatures, regardmg the predict~ons of the shear strength of RHSFCB have been evaluated stdtlst~cdlly based on the tot a1 number of 95 test results on RHSFCB faded In shear on shear flexu~al mode.

• Computers and Concrete
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• v.20 no.4
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• pp.391-407
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• 2017

Fiber reinforced polymer (FRP) bars have been recently used to reinforce concrete members in flexure due to their high tensile strength and especially in corrosive environments to improve the durability of concrete structures. However, FRPs have a low modulus of elasticity and a linear elastic behavior up to rupture, thus reinforced concrete (RC) components with such materials would exhibit a less ductility in comparison with steel reinforcement at the similar members. There were several studies showed the behavior of concrete beams with the hybrid combination of steel and FRP longitudinal reinforcement by adopting the experimental and numerical programs. The current study presents a numerical and analytical investigation based on the data of previous researches. Three-dimensional (3D) finite element (FE) models of beams by using ANSYS are built and investigated. In addition, this study also discusses on the design methods for hybrid FRP-steel beams in terms of ultimate moment capacity, load-deflection response, crack width, and ductility. The effects of the reinforcement ratio, concrete compressive strength, arrangement of reinforcement, and the length of FRP bars on the mechanical performance of hybrid beams are considered as a parametric study by means of FE method. The results obtained from this study are compared and verified with the experimental and numerical data of the literature. This study provides insight into the mechanical performances of hybrid FRP-steel RC beams, builds the reliable FE models which can be used to predict the structural behavior of hybrid RC beams, offers a rational design method together with an useful database to evaluate the ductility for concrete beams with the combination of FRP and steel reinforcement, and motivates the further development in the future research by applying parametric study.