• Journal of Korean Society of Water and Wastewater
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• v.24 no.4
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• pp.395-406
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• 2010

In this study, anaerobic digestion, electro-oxidation and electro-fenton oxidation processes were investigated to reduce oily refinery sludge. Anaerobic digestion process was not suitable for oily activated sludge reduction because of characteristics itself and, as experimental results revealed, reduction efficiency was low for electro-oxidation process. However, 40% total suspended solid reduction of oily activated sludge was obtained by electro-fenton oxidation process, operating at pH=1, 0.5 A and $Fe^{2+}$:$H_2O_2$ ratio = 1:30. In addition, higher reduction efficiency was obtained as reaction time was increased (30, 60, 90, 120 min) despite of low $H_2O_2$ concentration. From the results, it has been investigated that electro-fenton oxidation is efficient process for oily activated sludge reduction.

• Journal of KSNVE
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• v.8 no.1
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• pp.112-121
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• 1998

In this report, Experimental analysis for main factors and analyzing methods of electro-magnetic noise and no loading noise was conducted because of noise of AC generator, which is peripheral equipment by reduction of engine noise that would be the main cause of vehicle radiation noise. In addition, This is intended to suggest the noise reduction development basis of AC generator for actual fan and electro-magnetic noise by making-analyzing-testing it's sample.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.38-41
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• 1994

The method of passivation for protecting the $Hg_{1-x}Cd_{x}$Te surface is important device fabrication process. Because the surface components are highly reactive leading to its chemical and electrical instability. Especially. the material of detecting for infrared radiation, of which composition is x=0.2 or 0.3, is narrow bandgap semi- conductor. The narrow bandgap semi conductors are largely governed by the properties of the semiconductor surface. The narrow bandgap semi-conductors are largely governed by the properties of the semiconductor surface. The electro-chemical processing of $Hg_{1-x}Cd_{x}$Te allows rigorous control of the surface chemistry and provides an in-suit monitor of surface reaction. So electro-chemical reduction at specific potential can be selectively eliminated the undesirable species on the surface and mainpulated to reproducibly attain the desired stoichiometry. This method shows to assess the quality of chemically treated good $Hg_{1-x}Cd_{x}$Te surface.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.2
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• pp.111-119
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• 2019

Electro-coagulation process has been gained an attention recently because it could overcome the membrane fouling problems in MBR(Membrane bio-reactor). Effect of the key operational parameters in electro-coagulation, current density(${\rho}_i$) and contact time(t) on membrane fouling reduction was investigated in this study. A kinetic model for ${\rho}_i$ and t required to reduce the membrane fouling was suggested under different MLSS(mixed liquor suspended solids) concentration. Total 48 batch type experiments of electro-coagulations under different sets of current densities(2.5, 6, 12 and $24A/m^2$), contact times(0, 2, 6 and 12 hr) and MLSS concentration(4500, 6500 and 8500mg/L) were carried out. After each electro-coagulation under different conditions, a series of membrane filtration was performed to get information on how much of membrane fouling was reduced. The membrane fouling decreased as the ${\rho}_i$ and t increased but as MLSS decreased. Total fouling resistances, Rt (=Rc+Rf) were calculated and compared to those of the controls (Ro), which were obtained from the experiments without electro-coagulation. A kinetic approach for the fouling reduction rate (Rt/Ro) was carried out and three equations under different MLSS concentration were suggested: i) ${\rho}_i^{0.39}t=3.5$ (MLSS=4500 mg/L), ii) ${\rho}_i^{0.46}t=7.0$ (MLSS=6500 mg/L), iii) ${\rho}_i^{0.74}t=10.5$ (MLSS=8500 mg/L). These equations state that the product of ${\rho}_i$ and t needed to reduce the fouling in certain amounts (in this study, 10% of fouling reduction) is always constant.

• Journal of Korean Medicine for Obesity Research
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• v.3 no.1
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• pp.61-67
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• 2003

Objectives : To compare the reduction of thigh circumference between electro acupuncture treatment group and no treatment controlled group. Method : Trial was carried out 24 volunteers for 2 weeks. Volunteers were divided into 2 groups ; electro acupuncture and very low calorie diet group(n=8) or only very low calorie diet group(n=9). The main outcome of measure was the reduction of thigh circumference(cm) per weight loss(kg). Result: The main outcome measure showed no significant difference(p=0.14). There was no significant difference in weight loss(p=0.67) either.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.4
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• pp.112-120
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• 2012

In this paper, we manufactured the wireless video stream system after we scanned EMI(Electro Magnetic Interference)noise in the system. and then, we analysed the noise frequency in the interface, circuit and PCB(Printed Circuit Board). we suggested EMI noise reduction technique. The applied reduction method is low pass filtering, the internal layer placement for high speed video data line and optimization of the system ground condition. the manufactured system improved about 2 ~ 20[dB] margin for EMI limit 40[dBuV/m] at 30 ~ 230[MHz] and 47[dBuV/m] at 230 ~ 1000[MHz].

• The Journal of Korean Physical Therapy
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• v.19 no.6
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• pp.43-47
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• 2007

Purpose: This study examined the effect of electro-acupuncture stimulation of the infraspinatus and teres major on the shoulder function reduction. The subjects consisted of 20 female patients with a shoulder dysfunction. Methods: The 20 female patients with shoulder dysfunction participated voluntary in this research. 10 minute electro-acupuncture stimulation (frequency: 5Hz, Intensity: below the pain threshold) with Infra-red therapy, 3 times per week given to the patients' Trigger point of the infraspinatus and teres major. The Visual Analog Scale (VAS), Apley's Scratch Test and Global Perceived Effect Scale (GPES) were examined before alter six applications. Results: There was a significant decrease in the VAS (p<0.05) and Apley's Scratch Test (p<0.05). In addition, there was statistically significant increase in the Global Perceived Effect Scale (p<0.05). Therefore, the infraspinatus and teres major is a very important muscle for the shoulder function. Conclusion: This data will be used to develop a treatment method for patients with a shoulder dysfunction. These results suggest that the electro-acupuncture stimulation into the infraspinatus and the teres major Trigger point is an effective intervention for patients with shoulder dysfunction and pain.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.105-114
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• 2018

Membrane fouling in EC-MBR (Electro-Coagulation aided Membrane Bio-Reactor) processes was evaluated according to the operating parameters, such as current density and contact time. In addition, the fouling mechanism was investigated. Compared to the control (i.e., no electro-coagulation), membrane fouling for filtration of the activated sludge suspension after electro-coagulation was reduced significantly. Membrane fouling was improved further when the contact time was doubled under a low current density of $2.5A/m^2$. On the other hand, membrane fouling was not mitigated further, as expected, even though the contact time was doubled from 12 to 24 hr. at a current density of $10A/m^2$. This indicates that the overall decrease in membrane fouling is a function of the product of the current density and contact time. The particle size of the activated sludge flocs after electro-coagulation was changed slightly, which means that the membrane fouling reduction was not attributed to a larger particle size resulting from electro-coagulation. The experimental confirmed that the dynamic membrane made from aluminum hydroxide, Al(OH)3, and/or aluminum phosphate, Al(PO4), which had been formed during the electro-coagulation, played a key role on the reduction of membrane fouling. The dynamic membrane prevents the particles in the feed solution from deposition to the membrane pores and cake layers. Dynamic membrane formation as a result of electro-coagulation plays a critical role in the mitigation of membrane fouling in EC-MBR.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.5
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• pp.669-678
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• 2009

The reduction of excess activated sludge from petrochemical plant was investigated by the electro fenton (E-Fenton) process using electrogenerated hydroxyl radicals which lead to mineralization of activated sludge to $CO_2$, water and inorganic ions. Factors affecting the disintegration efficiency of excess activated sludge in E-Fenton process were examined in terms of five criteria: pH, $H_2O_2/Fe^{2+}$ molar ratio, current density, initial MLSS (mixed liquid suspended solids) concentration, $H_2O_2$ feeding mode. TSS total suspended solid and $TCOD_{cr}$ reduction rate increased with the increasing $H_2O_2/Fe^{2+}$ molar ratio and current density until 42 and $6.7 mA/cm^2$, respectively but further increase of $H_2O_2/Fe^{2+}$ molar ratio and current density would reduce the reduction rate. On the other hand, as expected, increasing pH and initial MLSS concentration of activated sludge decreas TSS and $TCOD_{cr}$ reduction rate. The E-Fenton process was gradually increased during first 30 minutes and then linearly proceed till 120 minutes. The optimal E-Fenton condition showed TSS reduction rate of 62~63% and $TCOD_{cr}$ (total chemical oxygen demand) reduction rate of 55~56%. Molar ratio $H_2O_2/Fe^{2+} = 42$ was determined as optimal E-Fenton condition with initial $Fe^{2+}$ dose of 5.4 mM and current density of $6.7{\sim}13.3 mA/cm^2$, initial MLSS of 7,600 mg/L and pH 2 were chosen as the most efficient E-Fenton condition.

• Journal of Korean Medicine for Obesity Research
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• v.2 no.1
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• pp.13-23
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• 2002

Background & Methods: In order to study the effect of electro-lipolysis-acupuncture, 57 outpatients who have had herbal medication in Kirin Oriental Hospital were devided to two groups; acupuncture-treated group(46) vs non-acupuncture-treated group(11) Acupuncture-treated group was given electro-lipolysis-acupuncture at least two times a week and administered with herbal diet medication, whereas non-acupuncture-treated group was administered only with herbal diet medication. Results: Mean age, body weight and BMI of these two group at the start point of the treatment were $27.22({\pm}7.64)\;vs \;29.09({\pm}8.73),\;67.76({\pm}9.34)\;vs\;67.00({\pm}10.69),\;and\;26.20({\pm}3.02)\;vs\;26.14({\pm}4.10)$ in the order of acupuncture-treated and non-acupuncture groups. After one month of treatment, change rate of body weight, BMI, total fat, percentage of fat was significantly higher in acupuncture-treated group. Also the change rate of arm circumference, hip circumference and thigh circumference was significantly higher in acupuncture-treated group. The change rate of abdominal circumference and WHR of acupuncture-treated group was higher than that of non-acupuncture-treated group with no statistical significance. The circumference reduction rate according to herbal dieting program was higher in this order, abdomen, arms, chest, thighs and hips. On the other hand, chest circumference change rate over weight loss rate, which is the portion no acupuncture treatment was given to, and AMC change rate was higher in non-acupuncture-treated group. Conclusion: These results imply that herbal dieting program combined with electro-lipolysis-acupuncture is more effective on reducing body fat, size reduction of localized obesity and preservation of muscle than herbal prescription only dieting program.