• Korea-Australia Rheology Journal
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• v.13 no.1
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• pp.37-45
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• 2001

Numerical simulation of coextrusion process of viscoelastic fluids within a die has been carried out. In the coextrusion process velocity profile at the outflow boundary is not known a priori, which makes it difficult to impose the proper boundary condition at the outflow boundary. This difficulty has been avoided by using the open boundary condition (OBC) method. In this study, elastic viscous stress splitting (EVSS) formulation with streamline upwind (SU) method has been used in the finite element method. In order to test the validity of the OBC method, comparison between the results of fully developed condition at the outlet and those of OBC has been made for a Newtonian fluid. In the case of upper convected Maxwell (UCM) fluid, the effect of outflow boundary condition on the interface position has been investigated by using two meshes having different downstream lengths. In both cases, the results with the OBC method showed reasonable interface shape. In particular, for the UCM fluid the interface shape calculated with OBC was independent of the downstream length, while the results with the zero traction condition showed oscillation of interface position close to the outlet. Viscosity difference was found to be more important than elasticity difference in determining the final interface position. However, the overshoot of interface position near the con-fluent point increased with elasticity.

• Journal of Plant Biology
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• v.38 no.1
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• pp.11-18
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• 1995

Mercury-induced changes in Chl a fluorescence induction kinetics of scratched barley leaf segments were dependent on the presence of light. By the treatment of 50$\mu$M HgCl2 under light condition, Fm and Fp were decreased. However, they were not significantly reduced under dark condition even after 2 h of mercury treatment. Under dark condition the decrease in variable fluorescence (Fv) after P transient was blocked within 20 min of the treatment. The analysis of fast fluorescence rise curve suggests that the inhibitory site of mercury under both light and dark conditions is not at QB binding site and the inhibition does not involve the increase in inactive PSII centers. Under light condition the decrease in Fp was partially recovered by addition of 50 $\mu$M NH2OH. These results suggest that a major inhibitory site of mercury under dark condition is at the reducing side of PSII and the site under light condition is at the oxidizing side of PSII possibly in addition to the one under dark condition. Under both light and dark conditions, energy-dependent quenching(qE) was alomost completely repressed within 20 min of mercury treatment and noticible change in Fo was not observed. The qE repression is probably due to the blockage of transthylakoid ΔpH formation.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.5
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• pp.27-38
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• 2021

The physical condition assessment criteria of fill dam safety inspection are now weakly regulated and inappropriate for small agricultural reservoirs since these criteria have fundamental backgrounds suitable for large-scale dams. This study proposes the degree (critical values) of defects for the quantitative condition assessment of the embankment in order to prepare the condition assessment criteria for a small reservoir with a storage capacity of less than one (1) million cubic meters. The critical values of defects were calculated by applying the method that considers the size ratios based on the dimensional data of reservoirs, and the method of statistical analysis on the measured values of the defect degree which extracted from comprehensive annual reports on reservoir safety inspection. In comparison with the current criteria, the newly proposed critical values for each condition assessment item of the reservoir embankment are presented in paragraphs 4 and 6 of the conclusion. In addition, this study presents a method of displaying geometric figures to clarify the rating classification for condition assessment items with the two defect indicators.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.100-101
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• 2021

Facilities with high risk of a disaster or requiring continuous safety management are designated as class-III facility. In order to designate a class-III facility, it is evaluated based on the safety status of the facility, the risk to the building users, and the number of years elapsed of the facility, etc. and this shall be referred to the actual condition survey for the designation of a class-III facility. In the actual condition survey conducted to designate the safety status is calculated by the checklist based on the evaluation scores consisting of five stages each item, and is evaluated in three stages by 'good', 'careful observation', and 'designated review' through the average of the combined scores. Currently, the actual condition survey being conducted applies only structural stability, and the risk factors such as damage to the finish, the risk of cracking, and the type and weight of major structures are not included in the checklist for the actual condition survey, so even if experts think it is dangerous, scores cannot be reflected. Therefore, this study aims to analyze the problems of checklist of the actual condition survey for the designation of class-III facility and to propose an improvement plan for the checklist for the actual condition survey.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.8
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• pp.30-35
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• 2013

This paper describes the assessment method of deterioration condition for a power transformer using SFRA. Frequency Response Analysis(FRA) is a method to evaluate the mechanical and geometrical integrity of the core and windings within a power transformer by measuring the electrical transfer functions over a wide frequency range. SFRA is sweep frequency response analyzer for power transformer winding diagnosis. The FRA is a comparative method, that evaluates the transformer condition by comparing the obtained set of FRA results to reference results on the same, or a similar, unit. FRA techniques were widely used and much more sensitive than the traditional and internationally accepted method of impedance measurements, but that work was required on standardization and interpretation. In order to analyze the deterioration condition for power transformer, overvoltage test and mechanical distortion test were carried out. The deterioration condition for power transformer was evaluated by SFRA. It is intended to present the elemental technology of assessment method for power transformer using SFRA.

• Journal of Microbiology and Biotechnology
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• v.18 no.12
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• pp.1958-1965
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• 2008

A denitrifying polyphosphate-accumulating bacterium (YKP-9) was isolated from activated sludge of a 5-stage biological nutrient removal process with step feed system. This organism was a Gram-negative, coccus-shaped, facultative aerobic chemoorganotroph. It had a respiratory type of metabolism with oxygen, nitrate, and nitrite as terminal electron acceptors. The 16S rRNA gene sequence of strain YKP-9 was most similar to the 16S rRNA gene sequence of Paracoccus sp. OL18 (AY312056) (similarity level, 97%). Denitrifying polyphosphate accumulation by strain YKP-9 was examined under anaerobic-anoxic and anaerobic-oxic batch conditions. It was able to use external carbon sources for polyhydroxyalkanoates(PHA) synthesis and to release phosphate under anaerobic condition. It accumulated polyphosphate and grew a little on energy provided by external carbon sources under anoxic condition, but did neither accumulate polyphosphate nor grow in the absence of external carbon sources under anoxic condition. Cells with intracellular PHA cannot accumulate polyphosphate in the absence of external carbon sources under anoxic condition. Under oxic condition, it grew but could not accumulate polyphosphate with external carbon sources. Based on the results from this study, strain YKP-9 is a new-type denitrifying polyphosphate-accumulating bacterium that accumulates polyphosphate only under anoxic condition, with nitrate and nitrite as the electron acceptors in the presence of external carbon sources.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.1039-1048
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• 2012

Objectives : The objective of this paper is to clarify the factors of the geriatric oral health influencing oral health-related quality of life by using the contracted OHIP-14 tool. Methods : This research conducted individual interview for 177 seniors using senior citizen center by using structured questionnaires. SAS(Ver.9.2) Program was used for the collected data to perform frequency analysis, reliability and scale analysis, t-test, ANOVA, correlation analysis and multiple regression analysis. Results : The oral health-related quality of life level related to oral health according to the demographical characteristics showed that it was better in case that they are younger, married, more educated and have more living expenses. Except for age, oral health-related quality of life was connected to scholastic achievement, living expenses, subjective health condition and subjective oral health condition. The factors influencing the oral health condition were subjective health condition, marriage, scholastic achievement, living expenses, age and sex. As the subjective health condition is better, in case of cohabitation of only a couple and as the age or scholastic achievement is higher and the living expenses are more, the oral health condition was better. The factors influencing oral health-related quality of life were subjective oral health condition, marriage, sex, subjective health condition, scholastic achievement and living expenses. As the subjective oral health condition and health condition were better and in case of sole living and cohabitation of only a couple, male's oral health-related quality of life was higher. Conclusions : It is considered that because the geriatric oral health condition becomes an important factor to oral health-related quality of life, the development of the geriatric oral health business and the geriatric heal education program to maintain and improve oral health is required and the activation of the oral health insurance policy for preventive dental service is necessary.

• Journal of Biosystems Engineering
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• v.30 no.2 s.109
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• pp.69-74
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• 2005

This study was carried out to investigate experimentally the effect of the ground condition and tire inflation pressure on rolling characteristics of towed wheel, including the deformation, sinkage, effective rolling radius and motion resistance of tire. The experiment was performed at soil bin for the three levels of off-road conditions(ground-I, ground-II and ground-III) and a on-road condition(ground-IV), and for the four levels of tire inflation pressure which were 80 kPa, 160 kPa, 240 kPa and 320 kPa. The results of this study are summarized as follows: 1. As the tire inflation pressure of towed wheel increased, the tire deformation decreased exponentially, but the tire sinkage increased exponentially. This trend was getting bigger as ground condition was getting softer. 2. The increase of tire inflation pressure increased the effective rolling radius of towed wheel, and this kind of trend occurred greatly as ground condition was soft. As a result, the effective rolling radius for the off-road condition was always larger than that for on-road condition. 3. For the on-road condition, as the tire inflation pressure of towed wheel increased, the motion resistance decreased, but for the off-road condition, augmentation of tire inflation pressure increased the motion resistance. Also, the effect of inflation pressure on motion resistance appeared great as ground condition was soft. Therefore, in order to improve the tire performance by the control of inflation pressure, it is desirable to reduce the tire inflation pressure for off-road condition and to increase the tire inflation pressure for on-road condition.

• Journal of Biosystems Engineering
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• v.27 no.6
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• pp.501-512
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• 2002

Traction performance of off-road vehicles is estimated using slip-traction relationships Two zero condition accepted by ASAE have been used widely to obtain the slip-traction relationships of off-road vehicles. This study was carried out using the soil bin systems to investigate the characteristic of slip-traction curves obtained using two zero conditions defined by ASAE. which are driving and driven zero condition, and to present disadvantage of slip-traction relationship based on two zero conditions of ASAE. The results of this study are summarized as follows : 1. For the driving zero condition, the curve of slip-traction relationship shows some issues. The first question is that the slip is zero when the traction is zero. The second question is that the value of slip is smaller than that of corresponding real slip, as the rolling radius decreased f3r the setting zero condition with driving wheel. 2. For the driven zero condition. slip occurs when the traction is zero, which is more realistic results than driving zero condition. But when a zero condition is set, skid occurs and this result increased the rolling radius of tire and increased slip value f3r the specific traction value of whole slip range. This kind of trend was getting bigger as the soil is softer, or the tire inflation pressure is higher. 3. From the results of this study, it was found that slip-traction relationship obtained by two zero conditions of ASAE is not realistic in estimating the traction performance of off-road vehicles. And also slip-traction relationship obtained for the same experimental condition showed different result in accordance with chosen zero condition,

• PNF and Movement
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• v.15 no.3
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• pp.361-371
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• 2017

Purpose: The purpose of this study was to examine the effects of performing a dual task on gait velocity, temporospatial variables, and symmetry in subjects with subacute stroke. Methods: The study included 14 independent community ambulators with gait velocity of 0.8m/s. The Korean mini-mental state examination, the Berg balance scale, the Trunk impairment scale, and the Fugl-Meyer assessment scale were used to recruit homogeneous subjects. Subjects performed a single task (10m ambulation at a comfortable speed) and a dual task (10m ambulation at a comfortable speed while carrying a water-filled glass). Gait variables were examined with the OptoGait system. Results: The findings of this study were as follows: 1) Gait velocity decreased significantly in the dual-task condition as compared to the single task condition. 2) There were no significant differences between the paretic and non-paretic stances. 3) Paretic swing decreased significantly in the dual-task condition as compared to the single task condition. 4) The non-paretic, double-limb support phase increased significantly in the dual-task condition as compared to the single- task condition. 5) There was no significant difference in temporal symmetry. 6) Non-paretic step length decreased significantly in the dual-task condition as compared to the single-task condition. 7) There was no significant difference in spatial symmetry. Conclusion: Performing dual tasks decreases gait velocity, paretic swing phase, and non-paretic step length, while it increases non-paretic double limb support. In addition, although there is no difference in temporospatial symmetry, there is high inter-subject variability in temporospatial symmetry. Thus, dual tasks should be selected in accordance with the functional level of the hemiplegic patient, and inter-subject variability of the individual should be considered when dual tasks are considered for gait-training of hemiplegic patients.