• Asian Journal of Atmospheric Environment
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• v.4 no.3
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• pp.177-188
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• 2010

The use of an activated carbon (AC) system alone has the limitation that the pollutants are not eliminated but only transferred to another phase with the consumed AC becoming hazardous waste itself. Therefore, the present study investigated the feasibility of using a combined system of granular AC (GAC) with S-doped visible-light-induced $TiO_2$ (GAC/S-doped $TiO_2$) to clean monocyclic aromatic hydrocarbons (MAHs) with concentrations at $\leq$ 3 mg $m^{-3}$, using a continuous air-flow reactor. This study conducted three different experiments: an adsorption test of pure GAC and GAC/S-doped $TiO_2$; a long-term adsorptional photocatalytic (AP) activity test of GAC/S-doped $TiO_2$; and an AP activity test of GAC/S-doped $TiO_2$ under different conditions. For the AP activity test, three parameters were evaluated: various weights of GAC/S-doped $TiO_2$ (0.9, 4.4, and 8.9 g); various flow rates (FRs) (0.5, 1 and 2 L $min^{-1}$); and various input concentrations (ICs) of the target MAHs (0.1, 1, 2 and 3 mg $m^{-3}$). The adsorption efficiencies were similar for the pure GAC and GAC/S-doped $TiO_2$ reactors, suggesting that S-doped $TiO_2$ particles on GAC surfaces do not significantly interfere with the adsorption capacity of GAC. Benzene exhibited a clear AP activity, whereas no other target MAHs did. In most cases, the AP efficiencies for the target MAHs did not significantly vary with an increase in weight, thereby suggesting that, under the weight range tested in this study, the weights or FRs are not important parameters for AP efficiency. However, ICs did influence the AP efficiencies.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.615-621
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• 2013

Membrane characterization methods for aqueous redox flow batteries aqueous RFBs were modified for non-aqueous RFBs. The modified characterization methods, such as ion exchange capacity, transport number, permeability and single cell test, were carried out to evaluate commercial membranes in non-aqueous electrolyte. It was found that columbic efficiency and energy efficiency in a single cell test were dependent on the ion selectivity of commercial anion exchange membranes. Neosepta AHA anion exchange membrane showed the anion transport number of 0.81, which is a relatively low ion selectivity in non-aqueous electrolyte, however, exhibited 92% of coulombic efficiency and 86% of energy efficiency in a single cell test. It was also found that a porous membrane without ion selectivity is suitable for a non-aqueous redox flow battery at a high current density.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.151-157
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• 1988

For the detection of the active cariogenic factors contributing to caries development, some practical methods such as the Snyder test, estimation of salivary flow rate and salivary buffering capacity test were evaluated statistically by comparing DMFT and DMFS indexes. Total 122 children (62 male and 60 female ; 64 rural and 58 urban) were selected ramdomly from the 6th grade of the primary school and their salivary cariogenic factors were analysed and evaluated. Among the total 122 children, 78.7% was positive in the snyder test in which the marked, moderate and slight caries activities were 29.5%, 30.3% and 18.9%, respectively. In the Snyder test, 74.45% was positive in urban children while 84.48% was positive in rural children. DMFT and DMFS indexes were markedly lower in negative group than positive group of the Snyder test (p<0.01). The mean and standard deviation of stimulated salivary flow rate was 6.97$\pm$2.57 in male and 6.34$\pm$2.54 in female but no significant difference was observed in sexuality. The stimulated salivary flow rate of urban children was slightly higher that of rural but there was no significant difference between them. However, the group that showed below average in the stimulated salivary flow rate was markedly higher in DMFI and DMFT indexes than the group of above average. The mean and standard deviation of stimulated salivary buffering capacity was 7.65$\pm$2.19 in male and 6.80$\pm$1.67 in female. This difference was significant statistically(p<0.05). Stimulated salivary buffering capacity of urban children was higher than that of rural. Increases in stimulated salivary flow rate and buffering capacity had reduced the onset of dental caries of 14-year-old permanent tooth.

• Polymer(Korea)
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• v.35 no.6
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• pp.586-592
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• 2011

In this study, we synthesized vinylbenzyl chloride-co-styrene-co hydroxyethyl acrylate (VBC-co-St-co-HEA) copolymer that can be applied to redox the flow battery process. The anion exchange membrane was prepared by the amination and crosslinking of VBC-co-St-co-HEA copolymer. The chemical structure and thermal properties of VBC-co-St-co-HEA copolymer and aminated VBC-co-St-co-HEA(AVSH) membrane were characterized by FTIR, $^1H$ NMR, TGA, and GPC analysis. The membrane properties such as ion exchange capacity(IEC), electrical resistance, ion conductivity and efficiency of all-vanadium redox flow battery were measured. The IEC value, electrical resistance, and ion conductivity were 1.17 meq/g, $1.9{\Omega}{\cdot}cm^2$, 0.009 S/cm, respectively. The charge-discharge efficiency, voltage efficiency and energy efficiency from all-vanadium redox flow battery test were 99.5, 72.6 and 72.1%, respectively.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.2
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• pp.184-193
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• 2008

The gate expansion was planed to increase discharge capacity of gate structure at sea dike in Asan Bay. So it was estimated for changing of hydraulic states in Pyeongteak Harbor Zone caused by gate expansion, using Delft3D, FLOW-3D and hydraulic physical scale model testing. In result, the influence of gate expansion was indicated to be weak.

• Journal of Power System Engineering
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• v.6 no.4
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• pp.16-22
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• 2002

This study was conducted to find performance evaluation method for automobile air conditioner. Experimental facilities were constructed to simulate wide range of operating condition for the automobile air conditioner. Compressor speed was controled by variable speed electric motor and the power was measured through torque transducer and tachometer was used to measure compressor speed. Parametric studies were conducted in this study, to figure out effect of environment variables on the performance of the automobile air conditioner. The environmental variables are inlet air temperature, relative humidity and air flow rate for the evaporator and inlet air temperature and air flow rate for the condenser. Compressor speed is also changed. The results of this study shows that air flow rate of the evaporator is more sensitive to the performance of the automobile air conditioner than the other variables. However relative humidity of the inlet air of the evaporator strongly affects capacity rather that COP.

• Journal of International Academy of Physical Therapy Research
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• v.6 no.2
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• pp.878-883
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• 2015

The purpose of this study compared the ability of feedback breathing training (FBT) and balloon blowing training to enhance the breathing of elderly people. The subjects were randomly and evenly divided into a feedback breathing training group (FBTG) and a balloon blowing training group (BBTG). Each group trained 3 times a week for 4 weeks, with the training suspended during the last 2 weeks. Pulmonary function measurements were obtained before the test and 2, 4 and 6 weeks after the test: forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FEV1/FVC, peak expiratory flow (PEF) and vital capacity (VC). A repeated-measures ANOVA was conducted for the significance test. The FBT resulted in a significant increase in the FVC, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. The BBT resulted in a significant increase in the FVC, FEV1, FEV1/FVC, PEF, and VC of the elderly smokers after 4 weeks and a significant decrease in the FVC, FEV1/FVC, and PEF after 6 weeks. In conclusion, An at home breathing rehabilitation program, in addition to balloon blowing, could increase the breathing performance of elderly people.

• Journal of Korean Society of Transportation
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• v.19 no.2
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• pp.21-28
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• 2001

This study is to estimate the through car equivalent for left-turn movement according to left turn radius in the signalized intersection. The saturation flow rate for left-turn movement in 92' KHCM(Korea Highway Capacity Manual) is the same as that for through movement in the signalized intersection where the left turn radius is over 20m. This study uses Duncan 'Test's Test in order to find out the saturated position for queued vehicle in the signalized intersection. It found that the saturated flow rate of left-turn movement in the signalized intersection is less than that of through movement where the left-turn radius is less than 20m. It found that the through car equivalents for left-turn movement according to left-turn radius(8m-20m) are between 1.05 and 1.14.

• Journal of Korean society of Dental Hygiene
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• v.20 no.5
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• pp.753-762
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• 2020

Objectives: This study was aimed at evaluating the effects of changes in the oral environment of the elderly in long-term care facilities after the intake of Weissella cibaria. Methods: The test group ingested the W. cibaria strain Chonnam Medical University (CMU), and the control group ingested the control food. Of all randomized trial subjects, 62 were analyzed (32 in the experimental group and 30 in the control group). In this 8-week demographic study, we evaluated self-perceived halitosis, changes in halitosis, sensory test results, tongue plaque index scores, saliva buffering capacity, and the salivary flow rate. Results: The W. cibaria CMU intake in the elderly in long-term care facilities during the experimental period did not demonstrate statistically significant changes in the salivary flow rate. However, self-perceived halitosis, organoleptic test results, tongue plaque index scores, and salivary buffering capacity demonstrated statistically significant differences between the experimental and control groups. These findings partially confirmed the beneficial effects of the W. cibaria CMU on the oral environment in the elderly. Conclusions: Research results on the role of probiotics in the oral cavity should be summarized, and utilization plans should be sought to obtain a clearer understanding of the clinical efficacy and related factors. The value of probiotic use may be high in improving the oral health of people by enabling treatment and prevention.

• International Journal of Concrete Structures and Materials
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• v.9 no.2
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• pp.185-206
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• 2015

This paper presents statistical models developed to study the influence of key mix design parameters on the properties of lightweight self-consolidating concrete (LWSCC) with expanded shale (ESH) aggregates. Twenty LWSCC mixtures are designed and tested, where responses (properties) are evaluated to analyze influence of mix design parameters and develop the models. Such responses included slump flow diameter, V-funnel flow time, J-ring flow diameter, J-ring height difference, L-box ratio, filling capacity, sieve segregation, unit weight and compressive strength. The developed models are valid for mixes with 0.30-0.40 water-to-binder ratio, high range water reducing admixture of 0.3-1.2 % (by total content of binder) and total binder content of $410-550kg/m^3$. The models are able to identify the influential mix design parameters and their interactions which can be useful to reduce the test protocol needed for proportioning of LWSCCs. Three industrial class ESH-LWSCC mixtures are developed using statistical models and their performance is validated through test results with good agreement. The developed ESH-LWSCC mixtures are able to satisfy the European EFNARC criteria for self-consolidating concrete.