• YAKHAK HOEJI
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• v.21 no.2
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• pp.87-94
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• 1977

The rheological properties of some honey-ginseng powder mixturs, used as pharmaceutical pills, were studied extensively by employing five kinds of honey, acacia, chestnut, buckwheat, green perilla and bush clover. Relation between the viscosity of the sample mixtures and the concentrations of ginseng powder and the temperature effect on the internal change of the structure were studied. The results obtained are as follows: 1) A complete gel formation of honey-ginseng mixtures was observed when about 50 days have passed after the sample preparation. 2) The viscosity of honey-ginseng powder mixtures was related with the concentration of ginseng powder, the temperature and the period of time required in gel formation as shown in the following equation. n=noexp$[{\kappa}_{1}c^{n1}+{\kappa}_{2}(T-273)^{-n2}+{\kappa}_{3} t^{n3}]$

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.82-88
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• 2015

Objectives: This study is designed to analyze the penetration performance into ceiling materials containing asbestos of scattering prevention agents and investigate the change in penetration depth and viscosity according to the dilution rate of anti-scattering agents diluted with distilled water. Methods: Five different types of scattering prevention agents were spread on plate-type asbestos ceiling materials. The penetration depth of each coated ceiling material was measured by energy dispersive spectroscopy (EDS) analysis, based on X-ray fluorescence (XRF) results of the non-coated ceiling materials. Test equipment installed the ceiling materials and 60 minutes were collected at a flow rate of $10{\ell}/min$ at a filter of 25 mm. Results: An EDS analysis of the cross-section of ceiling materials constructed with a scattering prevention agent revealed that potassium is detected in the process of penetrating hardener solidification and this element could be an indicator for infiltration. When anti-scattering agents with different viscosities were constructed and the penetration depth was analyzed by potassium detection assessment using EDS, the depth results with viscosities of 5.0, 2.5, and 1.9 cP were 98.5, 103, and $147{\mu}m$, respectively. Penetration performance improved with decrease in viscosity. Conclusions: For asbestos ceiling materials, it is concluded that a higher dilution rate of the scattering prevention agent leads to lower viscosity, and hence a deeper penetration depth from $156{\mu}m$ to 3 mm. The asbestos anti-scattering properties according to the penetration depth will be confirmed through further study.

• The Korean Journal of Food And Nutrition
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• v.33 no.4
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• pp.440-446
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• 2020

The purpose of this study was to derive the conditions for manufacturing rice porridge with optimum properties after reheating. The characteristics of rice porridge according to the soaking time, water addition rate, heating temperature, heating time, and cooling conditions were compared using the 'Samkwang' cultivar. In Step I, as the heating temperature increased, the weight change decreased and the viscosity increased, and the temperature known as the main factor of the gelatinization also appeared to affect the viscosity increase. In Step II, the viscosity and the texture properties was not significantly different as the soaking time was reduced, and 10 minutes was suitable because of due to the shortening effect of the total process time. In Step III, the residual heat was lowered by cooling after the rice porridge production, so the viscosity could be greatly reduced. Also, it was confirmed that the water addition rate of 900% and the heating temperature of 15 minutes were optimal manufacturing conditions. The next study will investigate the porridge processability of rice cultivars using these results.

• Food Science of Animal Resources
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• v.20 no.1
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• pp.21-29
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• 2000

This study was carried out to investigate the fermentation characteristics and storage of set-type yoghurt added mugwort extracts(AME) such as pH, growth of lactic acid bacteria, number of viable cells, viscosity, and sensory characteristics during 24 hours fermentation and 15 days storage. Addition of mugwort extracts was grown rapidly of lactic acid bacteria rather than that of control and also 4 or 8% AME groups were grown similar to control. The drop of AME pH of broth was less compared with control during incubation of lactic acid bacteria. The growth of lactic acid bacteria during incubation of AME yoghurt was not different of viable cell count between AME group and control in beginning time, but the viable cell count of AME groups were increased depended opon addition quantity of AME in ending time. Addition of mugwort extracts was not affect on pH change during yoghurt fermentation and increased a lactic acid bacteria number as well as no effect of yoghurt fermentation in ending time. The viscosity of yoghurt was almost not changed 3 hours after yoghurt mix and increased rapidly 6 hours after yoghurt mix. Although control and 0.5% AME group showed maximum viscosity at 18 hours of fermentation, 1 and 2% AME group showed linear increase until 24 hours of fermentation. Mugwort did not affect pH and viable cel number of lactic acid bacteria during 15 days storage 24 hours after fermentation. Sensory evaluation of the AME yoghurt showed that flavour, texture and acid taste were not affected by addition of mugwort. However, the appearance and taste were dropped by addition of mugwort.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.9
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• pp.909-916
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• 2016

The purpose of this study is to investigate the effect of swallowing training of high viscosity bolus for swallow function of stroke patients with dysphagia. This study subjects, acute stroke 18 patients, which were recruited to receive treatment in inpatient at general hospital, located in Kyunggido. Subjects were randomly allocated in experimental group and control group. Experimental group performed swallowing training of high viscosity bolus, while control group conducted Traditional dysphagia therapy. Both groups received treatment 30 minutes a day five times a week for four weeks. The assessment was conducted FDS(: Functional Dysphagia Scale), PAS(: Penetration Aspiration Scale), ASHA NOMS(: American Speech-language-hearing Association National Outcomes Measurements System Swallowing Scale) to compare swallow function for both group. Both groups showed significant improvements after intervention in all measures(p<.05). Change score between the two groups showed a significant improvement on experimental group than control group in FDS(p<.05). Swallowing training of high viscosity bolus could have a positive impact on swallow function for acute stroke patients with dysphagia.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.68-75
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• 2017

The study investigates the effects of the content and using method of chemical admixtures such as superplasticizer and viscosity modifying admixture on the fluidity, bleeding ratio, volumetric change and compressive strength of the grout in order to provide basic data for the development of high-quality grout for prestressed concrete. It appeared that the combination of superplasticizer and viscosity modifying admixture decreased the fluidity of grout with small content of superplasticizer. On the contrary, Grout used more than 0.1% of superplasticizer appeared to have significant effect on the improvement of the fluidity. On the other hand, bleeding of grout reduced according to increasing the content of viscosity modifying admixture. Superplasticizer with less than 0.05% had practically no effect on the reduction of bleeding, whereas superplasticizer with more than 0.1% appear to have significant effect on the reduction of bleeding. Also the combination of superplasticizer with 0.15% and viscosity modifying admixture with 0.15% resulted in satisfactory fluidity accompanied with fair reduction of bleeding and shrinkage of the grout.

• Fibers and Polymers
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• v.6 no.2
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• pp.103-107
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• 2005

An attempt was made to correlate the polymerization temperature and rheological and thermal properties of acrylonitrile (AN)-acrylamide (AM) copolymers. The copolymers were synthesized at different polymerization temperature. The copolymer structure was characterized by gel permeation chromatography (GPC) and Infrared spectrum (IR). The rheological and thermal properties were investigated by a viscometer and differential scanning calorimeter-thermogrametric (DSC-TG) analysis, respectively. When the polymerization temperature increased from $41^{\circ}C\;to\;65^{\circ}C$, the molecular weight $(\bar{M}_w)$ of copolymers decreased from 1,090,000 to 250,000, while its conversion increased from $18\%\;to\;63\%$, and the polymer composition changed slightly. To meet the requirements of carbon fibers, the rheological and thermal properties of products were also investigated. It was found that the relationship between viscosity and $\bar{M}_w$ was nonlinear and the viscosity index (n) decreased from 3.13 to 2.69, when the solution temperature increased from $30^{\circ}C\;to\;65^{\circ}C$. This suggests the dependence of viscosity upon $\bar{M}_w$ is higher at lower solution temperature. According to the result of activation energy, the sensivity of viscosity to solution temperature is higher for AN-AM copolymers synthesized at higher polymerization temperature. The result of thermal analysis shows that the copolymers obtained at higher polymerization temperature are easier to cyclization evidenced from lower initiation temperature. The weight loss behavior changed irregularly with polymerization temperature due to irregular change of liberation heat.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.2
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• pp.78-83
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• 2007

An experimental study has been carried out to analyze the thermal stability and to estimate the lifetime of refrigerating lubricants. PAG and POE oil are considered as test oils in this study. The viscosity of PAG and POE oil was measured by the vibration type viscometer while temperature is varied periodically in the range of $0^{\circ}C{\sim}100^{\circ}C$. In order to estimate lifetime of PAG and POE oil with temperature, the viscosity was measured while the test temperature of oils was maintained continuously at $180,\;200\;and\;220^{\circ}C$. The lifetime of oils is estimated as the decrease in viscosity change by 15%. The results indicate that the reduction rates of viscosity of PAG and POE oil are less than 5% after 510 temperature variation cycles. However, when the oils are kept at high temperature, it is found that the lifetimes of PAG oil is seen to be 244, 177 and 89 hours at the test temperature of $180,\;200\;and\;220^{\circ}C$, respectively, where as the lifetimes of POE oil are estimated to be 1,744, 1,007 and 334 hours at the temperature of $180,\;200\;and\;220^{\circ}C$, respectively. Thus, the lifetime of POE oil is found to be much longer than that of PAG oil. The lifetime correlations of PAG and POE oil are also obtained by Arrhenius's equation method in this paper.

• Advances in concrete construction
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• v.16 no.1
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• pp.59-68
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• 2023

In the pumping process, concrete moves along the pipe and experiences both pressure and shear. This changes the workability and flow characteristics of the concrete. However, the effect of pressure and shear on the change in properties of concrete during the pumping process has not yet been accurately identified. This study analyzed the effects of pressure and shear on the properties of concrete during pumping. For quantitative tests, lab-scale test equipment capable of simulating the pressure and shear applied to concrete during pumping was used. For one coarse aggregate type, two paste types, three mortar types, and five concrete types, the effects of pressure, shear, and shear under pressure conditions were examined by varying the maximum pressure (0 to 200 bar) and the rotational speed of the vane for shear (0 to 180 rpm). Under the maximum pressure condition of 200 bar, the water absorption of coarse aggregate increased by 0.62% and that of fine aggregate also increased. When the concrete was under pressure, significant changes (a reduction in a slump and an increase in viscosity and yield stress) compared with the effect of the elapsed time occurred owing to an increase in the water absorption of the aggregates. When both pressure and shear were applied to concrete, both the slump and viscosity decreased. As the rotational speed of the vane increased, changes in properties became significant. Shearing in the absence of pressure maintained the properties of concrete. However, shearing under pressure conditions caused a reduction in slump and viscosity.

• Tribology and Lubricants
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• v.30 no.3
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• pp.168-176
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• 2014

This paper presents an engine oil change warning algorithm based on the test results of a small dip-stick-gage-type engine-oil-deterioration-detection sensor, software to realize the algorithm and a display device to apply the software. The algorithm determines the engine oil deterioration condition from the rate of change in the dielectric constant based on the average measured capacitance at $80^{\circ}C$ after the engine stops. The rate of change in the dielectric constant at the time for oil change correlates with the time that one of recommended warning limits for engine oil physical properties such as TAN (Total Acid Number), TBN (Total Base Number) and viscosity is first reached. At this point, a warning signal for oil change appears on the display device like a smart-phone or individual display device. The frames of smartphone app have three stages. The user can directly input all of the thresholds into the frame of the smartphone app. The screen of the display device comprises one frame for each warning signature with the related message. The user can input the thresholds to the device through a USB cable connected to a personal computer.