• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1991년도 봄 학술발표회 논문집
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• pp.87-92
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• 1991

Since the material property of binder in polyester polymer concrete has a viscous mechanism, the workability of polyester polymer concrete mixture showed different characteristics from that of cement concretes. Therefore, this study was devised to evaluate workability characteristics of polyester polymer concrete using slump and flow tests. Study results showed that the test temperature and ST/UP ratio were the most dominantly affecting factor on the viscosity of binder, and viscosity of the binder was strongly correlated with the workability of polyester polymer concrete mixture.

• 한국유체기계학회 논문집
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• 제7권2호
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• pp.21-26
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• 2004

In this study the effects of fluid viscosity on the pump performances for a conventional centrifugal pump were experimentally investigated. The study aimed to compare the pump characteristics between water and viscosity fluids. In order to measure the flow rate and pressure, v-notch welt and bourdon pressure gauges were used for the codes of KS B6301 and KS B6302. The working fluids were water, aqueous sugar and glycerin solutions. The results were summarized as follows : The experimental results were summarized as follows : the pump characteristics of the total head, shaft power, and efficiency with high viscosity fluids were different from those of water. When the viscosity of the applied fluid was increased, the total head and efficiency were more decreased than those of water. The decreasing gradients of the total head and the efficiency were larger than water due to the increased disk friction losses at the duty operation point. However, the shut-off head was almost constant regardless the viscosity of applied fluids. Each efficiency curves for the sugar $20w\%$ and glycerin $20w\%$ solutions was decreased up to $15.1\%$ and $34.4\%$ than that of water, respectively.

• 대한기계학회논문집B
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• 제20권12호
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• pp.4053-4061
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• 1996

Internal flow characteristics within Y-jet atomizers and the local drop size distribution and cross-sectional averaged drop size at the outside were investigated with the liquid and air injection pressures, mixing port length of atomizers, and the liquid properties taken as parameters. To examine the effect of the liquid viscosity, glycerin-water mixtures were used in this study. The liquid viscosity plays only a minor role in determining the internal flow pattern and the spatial distribution shape of drops, but the drop sizes themselves generally increase with increasing of the liquid viscosity. An empirical correlation for the liquid discharge coefficient at the liquid port was deduced from the experimental results; the liquid discharge coefficient strongly depends on the liquid flow area at the mixing point which is proportional to the local volumetric quality(.betha.$_{Y}$), and the volumetric quality was included in the correlation. Regardless of the value of the liquid viscosity, the compressible flow through the gas port was well represented by the polytropic expansion process(k=1.2), and the mixing point pressure could be simply correlated to the aspect ratio( $l_{m}$/ $d_{m}$) of the mixing port and the air/liquid mass flow rate ratio( $W_{g}$/ $W_{f}$) as reported in the previous study.udy.udy.y.

• 동아시아식생활학회지
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• 제20권4호
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• pp.567-574
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• 2010

This study was performed to evaluate the physicochemical and quality characteristics of dried noodles when different concentrations of Enteromorpha intenstinalis powder (EIP) were added to the wheat flour, thereby determining which noodle recipe was preferred. The cooking quality, mechanical texture properties, and viscosity of the prepared with noodles were measured, and then a sensory evaluation was conducted on them. The gelatinization points of the composite Enteromorpha intenstinalis powder-wheat flour were shown to have an increased viscosity at $95^{\circ}C$ after 15 minutes. As measured via amylograph, the maximum viscosity values of those samples decreased with increasing EIP content. Also, when increased amounts of EIP were added, both the L and b values were reduced, whereas the a value was increased. The color values, weight and volume of the cooked noodles increased, as did the turbidity of the soup. With regard to the textural characteristics, the EIP additive increased hardness and reduced adhesiveness, cohesiveness and springiness. Overall, according to the results of our sensory evaluations, the noodles prepared with 5% EIP were preferred over other noodles.

• 한국식품저장유통학회지
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• 제8권2호
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• pp.175-180
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• 2001

The quality characteristics of bread prepared with the addition of dried persimmon peel powder(PPP) were investigated. Visco-elastic characteristics of dough and texture of bread added PPP was examined by rapid visco-analyzer and texture analyzer. The maximum viscosity of the dough with PPP was lower than that of control at 90$\^{C}$. Final viscosity after cooling to 50$\^{C}$, viscosity of control increased to 134 B.U., but that of the dough with PPP showed 13∼37 B.U. As more PPP was added, gluten formation and mixing time dough were longer. Adhesiveness, springness, cohesiveness and chewiness gradually increased as PPP content increased, while the hardness decreased. Lightness value decreased but redness and yellowness values increased with the addition of PPP, especially, the bread made by 15% PPP treatment showed dark brown color. In sensory evaluation of bread, score of color decreased significantly as more PPP was added but overall acceptability was not significant different(p<0.05) between control and 5% PPP treatment. It is considered that the addition of 5% was appropriate for bread making with PPP.

• 한국기계가공학회지
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• 제2권3호
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• pp.48-55
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• 2003

This study investigates the effect of temperature and electric field strength on the Bingham characteristics of Electro-Rheological(ER) fluids which change their Yield shear stress and viscosity by temperature and electric field strength. It is found that under constant temperature the Yield sheal stress and viscosity of ER fluids proportionally increase with the applied electric field strength, and under constant applied electric field strength the Yield shear stress and viscosity of ER fluids decrease with the increasing temperature. These results are considered to be applied to the fluid and pneumatic power industry.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.393-398
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• 1999

The temperature dependence of the viscosity was determined for an electrorheological(ER) fluid consisting of 35 weight% zeolite particles in hydraulic oil 46cSt. Thermal activation analysis were performed by changing the ER fluid's temperature from -1$0^{\circ}C$ to 5$0^{\circ}C$ at fixed electric field. According to the analysis, the activation energy for flow was about 79.64kJ/mole at E=0kV/mm. Generally, the hydraulic oil 46cSt will be operated at the temperature of about 4$0^{\circ}C$, the ER fluid's electric field dependence of viscosities were investigated at this temperature. also, the influence of adding the dispersant(Carbopl 940) on electrorheological effect of the ER fluid was discussed.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2002년도 춘계학술대회 논문집
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• pp.54-57
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• 2002

In order to find the effect of lubricant viscosity, sheet surface roughness, tool geometry, and forming speed on the frictional characteristics in sheet metal forming, a sheet metal friction tester was designed and manufactured and friction tests of various sheets were performed. Friction test results showed that as the lubricant viscosity becomes lower, the friction coefficient is higher. When surface roughness is extreme1y low or high, the friction coefficient is high. As punch comer radius and punch speed are bigger, the value of friction coefficient is smaller. The sensitivity of friction coefficient is mainly governed by lubricant viscosity and sheet surface roughness.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.269-272
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• 2005

Epoxy resins are gradually becoming some of the most important and versatile polymers in modem civil engineering. Because epoxy resins have some unigue properties, such as toughness, versatility of viscosity and curing conditions, good handling characteristics, high adhesive strength, inertness, low shrinkage compared to most other thermo-setting resins and concrete, and resistance to chemicals, they have found many applications in construction castings, repair materials, road or bridge deck pavements, coatings, and as structural or non structural adhesives. In this applications, epoxy resins are widely used for polymer concretes, grouting materials, injection glues, and sealants. In this paper, characteristics of deformation of repair material after repaired have been investigated by viscosity of repair material and the width of crack. It is believed that flexural strength of epoxy resin with low viscosity is high because tensile strength is high and elongation at break is low, fracture energy is low.

• 한국식생활문화학회지
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• 제29권2호
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• pp.205-211
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• 2014

This study investigated the quality of noodles containing different amounts of Ligularia fischeri powder (LFP). Noodles were prepared at ratios of 0, 1, 3, 5, and 7% LFP based on flour weight. Cooking quality, mechanical texture properties, and viscosity were measured, and a sensory evaluation was performed with the prepared noodles. Gelatinization points of the composite LFP-wheat flours increased. As measured via amylography, viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity values of samples decreased, as the LFP content increased. As increasing amounts of LFP were added, the L, a, and b values decreased while color values, weight, and volume of cooked noodles increased, as did the turbidity of the soup. With regard to textural characteristics, LFP additive increased hardness, cohesiveness, and springiness, while decreasing adhesiveness. Sensory evaluation showed that high quality cooked noodles could be produced by inclusion of 3% LFP.