• Journal of the Korean Electrochemical Society
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• v.6 no.2
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• pp.103-112
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• 2003

Various kinds of metals were coated on synthetic graphite in order to investigate the relationship between film characteristics and their electrochemical performance. Gas suspension spray coating method was employed for the coating of synthetic graphite. In our experimental range, all of the metal coated synthetic graphite showed the higher capacity than that of raw material at high C-rate mainly due to decrease in impedance of passivation film. In cyclic voltammetry experiments, silver-coated and tin-coated graphite anodes found the lithium-alloy reaction. Considering smaller amount of metal coating, the most increase in discharge capacity was caused by improvement of conductivity of the electrode. When single-component metal was coated, silver-coated graphite anode exhibited the highest discharge capacity and better cycleability. Double components of silver-nickel coated active material showed the highest discharge capacity, rate capability and the best cycle performance in the range of our experiments.

• Polymer(Korea)
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• v.25 no.6
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• pp.765-773
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• 2001

In In order to remove harmful trace elements such as $Co^{2+}$, $Ni^{2+}$ , $Cr_2O_7\;^{2-}$ from water, we synthesized AN-co-(MMA/IA) according to various mole ratio of monomers and spun by wet-spinning. And multi-functional PAN ion exchangers were prepared by hydrolysis. We observed structure, degree of functionalization, ion exchange capacity, distribution coefficient and mechanical properties for ion exchanger. Anion exchange capacity decreased in 4.5 ~ 4.2 meq/g with increasing of IA content and cation exchange capacity increased in 1.8 ~ 2.2 meq/g. Tensile strength of the ion exchanger increased up to 0.008 mol% IA content and appeared maximum value by 216$kg/cm^2$Distribution coefficient for AN-co-(MMA/IA) ion exchanger appeared maximum value for Co(II), Ni(II) in pH 5-6 range and for Cr(III) in pH 3-4 range. And the adsorption capacity was in the order of Cr(III) > Co(II) > Ni(II) for multicomponent in continuous process.

• The Journal of Korean Physical Therapy
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• v.30 no.3
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• pp.90-95
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• 2018

Purpose: To investigate the relationship between gross motor capacity and neuromuscular function in children with cerebral palsy (CP) through a short-term intensive intervention. Methods: Twenty-four children younger than 6 years of age (17 boys, 7 girls, mean $age{\pm}standard$ deviation, $42.71{\pm}14.43months$) who were diagnosed with CP underwent short-term intensive treatment for 8 weeks. An evaluation of gross motor function capacity using the gross motor function measure (GMFM-66 and GMFM-88) was performed to measure muscle strength, selective motor control (SMC), and spasticity, factors related to neuromusculoskeletal function. Changes in spasticity, strength, range of motion, selective motor function, and exercise intensity scores were evaluated in terms of the gross motor function classification system (GMFCS) and ages. Results: The GMFM-88 and GMFM-66 scores significantly increased, by $4.32{\pm}4.04$ and $2.41{\pm}1.51%$, respectively, following the 8-week intervention. The change in the GMFM-66 score did not reflect a statistically significant difference in the GMFCS level. However, there was a statistically significant difference in the GMFM-88 score change in individuals at GMFCS Level III, the strength and spasticity of subjects at GMFCS Levels I-II did not significantly differ (p<0.05). The changes in the GMFM-66 scores for strength, SMC, range of motion (ROM), and spasticity significantly differed according to age (p<0.05) in children aged 36 months and older. Overall, there was a statistically significant difference in strength, SMC, and spasticity (p<0.05) before and after intensive short-term treatment. Conclusion: The 8-week short-term intensive care intervention improved the motor function score of study participants, emphasizing the need for early intervention and additional research in this area.

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.61-72
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• 1997

This research aims to remove the heavy metals, nonbiodegradable COD(NBDCOD), and color using the coal waste. The experimental by heat treatment was performed to advance the adsorption capacity. The results are as follows ; i) The coal waste had the adsorption capacity of heavy metals and the rates were in the range of 20 to 30 percents. ii) The heat treatment was the optimum condition that the reaction time was 6 hours at $500^{\circ}C$, , iii) In the column experimen, non-treated coal waste removed the COD and color in the range of 20 to 60 percents. iv) Heat-treated coal waste showed higher removal rate of the color in biological effluent, and heavy metal and COD removal rates were changed by the filteration rates.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.2
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• pp.238-243
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• 2011

The ambient temperature of the experimental conditions changes by varying the speed of the compressor and the electronic expansion valve opening. The effects of changing valve opening to the entire system has been investigated. The results show that the ambient temperatures of $35^{\circ}C$ and $30^{\circ}C$ controlled at 30Hz must be avoided. The capacity control range of the control compressor with changing speed is about 43~100% at $35^{\circ}C$, 43~100% at $25^{\circ}C$ and 48~100% at $10^{\circ}C$, respectively. The results show the capacity control range decreases with decreasing ambient temperature.

• Carbon letters
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• v.1 no.1
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• pp.36-40
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• 2000

The initial irreversible capacity (IIC) of a hard carbon during the charge/discharge reaction is strongly affected by both the initial irreversible capacity on the carbon surface $(IIC_S)$ and the initial irreversible lithium insertion into carbon $(IIC_B)$. The initial coulombic efficiency of the insertion and the desertion of lithium (IIE) can be used as a performance to classify $IIC_B$ of the carbon. The $IIC_B$ was proportional to the specific discharge capacity with a slope, $IIE^{-1}$ - 1. The IIE of hard carbon had four regions. $IIE_A$ for the region of 0~95 mAh/g of $Q_{D1}$ was 60.2%. $IIE_B$ and $IIE_C$ for the regions of 95~172 mAh/g and 172~308 mAh/g had 84.9% and 91.5%, respectively. $IIE_D$ was appeared above 308 mAh/g. But, the $IIE_D$ was reduced to 82.1% compared with $IIE_C$. These IIE might be corresponding to lithium desertion from carbon at the region of 0~172 mAh/g range, lithium desertion from the micropore of carbon at the region of 172~308 mAh/g range, and to the lithium stripping of the plated lithium for the region above 308 mAh/g, respectively.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.65-71
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• 2016

The new concept of agricultural water supply potential, which is mean annual turnover rate times unit storage capacity, was introduced for agricultural reservoirs. We investigated characteristics of mean annual turnover rate and unit storage capacity for agricultural reservoirs with storage capacity of over $1million\;m^3$. The curve of agricultural water supply potential represents change in mean annul turnover rate according to change in unit storage capacity. The mean annual turnover rate and unit storage capacity in the reservoirs with high minimum storage ratio are significantly higher than those in the reservoirs with low minimum storage ratio. Most of unstable water supply reservoirs showed low mean annual turnover rate or low unit storage capacity, indicating that mean annual turnover rate may be an index of stability degree for agricultural water use. The reservoirs with mean annual turnover rate of over 2 and unit storage capacity of over 0.8 m may be estimated as the stable water supply zone for 10 frequency dry year. The reservoirs with high agricultural water supply potential can belong to the wide range of stable water supply zone. The results suggest that relation between mean annual turnover rate and unit storage capacity may be used in evaluating stability degree for agricultural water supply in the reservoirs.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1136-1143
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• 2008

The Vertical Drains(Sand Drains, Pack Drain, PBD) is used for Vertical Drains Method in domestic. Each of the drains is selected after it consider a field condition and efficiency of drain. A discharge capacity is very important factor, which to estimate a efficiency. And the smear Zone where disturbance area of in-suit by installation of Vertical Drains is important factor to select a drains. In this study, the complex discharge capacity test was operated for discharge capacity comparison of the Wing Drain and PBD. And a model test was operated to apprehend smear zone of the Wing Drain and PBD. From these tests, it was apprehended an engineering characteristic of vertical drain. The results of the complex discharge capacity test, a discharge capacity fell below $20cm^3/sec$ to $1cm^3/sec$ in more than overburden load $2.5kg/cm^2$. The Wing Drain maintained a over $40cm^3/sec$ in more than overburden load $2.5kg/cm^2$ and minimum discharge capacity $8cm^3/sec$. The results of the smear zone test, a influence bounds of smear zone was more larger in case of the Wing Drain(rectangle) than the PBD. But when a discharge capacity of Wing Drain is considered, it was concluded which smear zone bounds difference was effected in comparison with PBD. I think that it minimized a mandrel section to minimize a smear zone effect range

• Structural Engineering and Mechanics
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• v.65 no.5
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• pp.601-609
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• 2018

Steel bolts are used in the construction industry for a large variety of applications that range from fixing permanent installations to temporary fixtures. In the past much research has been focused on developing destructive testing techniques to estimate their pull-out load carrying capacity with very little attention to develop non-destructive techniques. In this regards the presented research work details the combined use of ultrasonic pulse velocity and Schmidt hammer tests to identify anchor bolts with faculty installation and to estimate their pull-out strength by relating it to the Schmidt hammer rebound value. From experimentation, it was observed that the load capacity of bolt depends on its embedment length, diameter, bond quality/concrete strength and alignment. Ultrasonic pulse velocity test is used to judge the quality of bond of embedded anchor bolt by relating the increase in ultrasonic pulse transit time to the presence of internal pours and cracks in the vicinity of steel bolt and the surrounding concrete. This information combined with the Schmidt hammer rebound number, R, can be used to accurately identify defective bolts which resulted in lower pull-out strength. 12 mm diameter bolts with embedment length of 70 mm and 50 mm were investigated using constant strength concrete. Pull-out load capacity versus the Schmidt hammer rebound number for each embedment length is presented.

• Steel and Composite Structures
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• v.9 no.5
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• pp.397-418
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• 2009

Eight panel specimens were tested in one-way bending to study the behaviour and capacity of composite slab joists consisting of cold-formed steel C-sections and concrete. Various shear transfer mechanisms were implemented on the C-section flange embedded in the concrete to provide the longitudinal shear resistance. Results showed that all specimens reached serviceability limit state while in elastic range and failure was ductile. Shear transfer achieved for all specimens ranged from 42 to 99% of a full transfer while specimens employed with shear transfer enhancements showed a greater percentage and therefore a higher strength compared with those relying only on surface bond to resist shear. The implementation of pre-drilled holes on the embedded flange of the steel C-section was shown to be most effective. The correlation study between the push-out and panel specimens indicated that the calculated moment capacity based on shear transfer resistance obtained from push-out tests was, on average, 10% lower than the experimental ultimate capacity of the panel specimen.