• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.784-789
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• 1997

Aluminium solid electrolytic capacitor in which electroconducting polypyrrole(PPy) is used as an electrolyte is studied. Pyrrole(Py) is electrochemically synthesized using the etched and anodized aluminium foil electrode($Al_2O_3$) as an anode on which the thin layer of chemicalpolymerized PPy as a pre-coating layer is formed previously by chemical oxidative polymerization(CP). Investigating the effects of the polymerization conditions on the electrical characteristics of resulting capacitors, the capacitors which were obtained from the galvanostatic electrolysis of pyrrole containing sodium p-toluenesulfonate(TsONa) under the currents of $2.0{\sim}4.0mA/unit(6.5{\times}10mm)$, showed the most superior properties.

• Journal of Acupuncture Research
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• v.22 no.6
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• pp.173-180
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• 2005

Objectives : The purpose of this study was to assess the effect auricular acupuncture for acute mental stress using power spectrum analysis of the heart rate variability(HRV). Methods : 10 healthy volunteers participated in this study. After 5 minute rest, the first mental stress was provided for 5 minute. And then subjects rested for 15 minute. The second mental stress was provided for 5 minute. The acupoint, Shin-Mun point of the ear was stimulated for 15 minute. HRV was recorded before and after the first and second mental stress, and after auricular acupuncture stimulation. Results : After mental stress, normalized LF and LF/HF ratio is significantly increased. Before and after simple rest, normalized LF and normalized HF is significantly changed, but LF and LF/HF ratio is not significantly changed. On the other hand, before and after auricular acupuncture treatment, normalized LF, normalized HF is significantly changed, and also LF and LF/HF ratio is significantly decreased. Conclusion : The result suggest that auricular acupuncture can decrease more significantly in cardiac sympathetic activity due to mental stress than simple rest.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.143-152
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• 2002

The growth of Polypyrrole film has been investigated during electropolymerization in an aqueous solution on bare and SAM modified gold electrodes by in-situ EQCM and ex-situ AFM. According to the result of cyclic voltammetry measurements, in the case of a bare gold electrode, the electrochemical deposition of polypyrrole were dependent on the limiting oxidative potential, but not on scan numbers. When the limiting potential higher than 0.8 V was applied on the electrode, the amount of polypyrrole deposited on a gold electrode was rapidly increased and the abnormal mass change attributed to the rearrangement of polypyrrole films was observed as the scan number increased. The polypyrrole film Prepared on electrodes modified with 1-dodecanethiol SAM or thiophene SAM grew 3-dimensionally with the rearrangement of film. However, in the case of BPUS SAM, 2-dimensional layer-by-layer growth of film was observed without the rearrangement of film. AFM images showed films with chain-shaped and/ or donut-shaped polymers when grown rapidly and a wrinkled film at the steady state condition.

• Journal of Advanced Navigation Technology
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• v.25 no.5
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• pp.370-376
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• 2021

development of the aerospace industry is increasing the research of projectiles. In addition, many tests are under way and many failures occur accordingly. Projectiles should be able to minimize failures because they are more dangerous than other electronic equipment. Therefore, it is necessary to verify wiring before powering the projectile. Accordingly, the wiring status was verified by resistance measurements. However, the wiring test of the previous resistance measurement method cannot be accurately measured due to devices such as capacitors and inductors in the projectile circuit. In this paper, impedance is measured in the connection state of cables and projectiles using a TDR meter. The Z-Segmentation algorithm is used to set the reference value for the measured steady state impedance. The Z-Segmentation algorithm first finds the peak values of the impedance waveform using a Kalman filter and obtains the final impedance peak segment through segmentation. In this way, the wiring status is determined based on the reference value for the normal state of the wiring.

• The Journal of Korean Medicine
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• v.16 no.1 s.29
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• pp.281-294
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• 1995

The effect of Sam Hwa San on the Na-K-ATPase activity was evaluated in microsomal fraction prepared from rabbit cerebral cortex to determine whether Sam Hwa San affects Na-K-ATPase activity of nervous system. Sam Hwa San markedly inhibited the Na-K-ATPase activity in a dose-dependent manner with an estimated $I_{50}$ of 0.12%. Optimal pH for the Na-K-ATPase activity was at 7.5 in the presence or absence of Sam Hwa San. The degree of inhibition by the drug more increased at acidic and alkalic pHs than neutral pH. Kinetic studies of substrate and cationic activation of the enzyme indicate classic noncompetitive inhibition fashion for ATP, Na and K, showing significant reduction in Vmax without a change in Km. Dithiothreitol, a sulfhydryl reducing reagent, partially protects the inhibition of Na-K-ATPase activity by Sam Hwa San. Combination of Sam Hwa San and ouabain showed higher inhibition than cumulative inhibition. These results suggest that Sam Hwa San inhibits Na-K-ATPase activity in central nervous system by reacting with, at least a part, sulfhydryl group and ouabain binding site of the enzyme protein, but with different binding site from those of ATP, Na and K.

• Korean Journal of Acupuncture
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• v.23 no.4
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• pp.101-110
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• 2006

Objectives : The purpose of this study was clinical observation about sensorineural hearing loss compare with acupucture treatment and assessments of prognotic factors. Methods : This study was clinical observation about sensorineural hearing loss cases. for diagnosing in these cases, pure tone audiometry was used. The treatment, acupuncture was used. Results : Three patients(37.5%) remarkably improved, one patient(12.5%), slightly improved, four patients(50%), no change. Conclusions : These results suggest that the prognosis by age and initial hearing threshold was significant. The treatment on sensorineural hearing loss considered that bone condution improved.

• Journal for History of Mathematics
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• v.27 no.5
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• pp.313-327
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• 2014

Based on the importance and the necessity of the study on history of mathematics and mathemtics education using history of mathematics for finding the cultural identity and values of our traditional mathematics, we refer to two types of teaching and learning methods utilizing 'WonYongSamBangHoGu', the second theme of 'SanSulGwanGyeon' written by Lee Sang Hyuk. First, we present various cases of 'WonYongSamBangHoGu' constructed utilizing kind of mathematics learning software, GeoGebra by high school freshmen belonging to the Education Centers for the Gifted in Seoul Science Park. Second, We modernly reinterpret the questions contained in 'WonYongSamBangHoGu' and show several developed items using it.

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.83-96
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• 2000

Objective This experimental study was designed to investigate effects of Sam-chool-gun-bi-tang administration during carbohydrate loading diet to long distance runners on changes of the urine metabolic responses. Materials and Methods All subjects were divided randomly with two groups, Sam-chool-gun- bi-tang administration Group (N=5) and control group (N=5) and attended on domestic marathon race. The urine samples were collected by 15ml conical tube at rest, a day before race, immediately after race, a day after race. These samples were used to analyze for the factors of the change on metabolic responses. At First, the factors of the routine urine test were checked; RBC, WBC, glucose, protein, ketone, bilirubin, urobilirubin. Next, the factors on the changes of the electrolyte metabolism and creatinine were checked; $Na^+ $, $Cl^-$, $K^+$, $Ca^{+ +}$, Creatinine. Results 1. Urine RBC, WBC, glucose, protein, ketone, bilirubin, urobilirubin were all denoted negatively (-). 2. Urine pH response in Sam-chool-gun-bi-tang administration group was shown significant difference between two groups at immediately after race. 3. Urine $Na^+$ response in Sam-chool-gun- bi-tang administration group was shown significant difference between two groups at immediately after race. 4. Urine $K^+$ response in Sam-chool-gun-bi-tang administration group was shown significant difference between two groups at immediately after race and a day after race. 5. Urine $Cl^-$ response in Sam-chool-gun- bi-tang administration group was increased at immediately after race, but was not shown significant difference between two groups. 6. Urine $Ca^{+ +}$ response in Sam-chool-gun-bi-tang administration group was decreased gradually, but was not shown significant difference between two groups. 7. Urine Creatinine response in Control group was decreased significantly at immediately after race, but was not shown significant difference between two groups. Conclusion According to the above results, it was shown that Sam-chool-gun- bi-tang administration had the positive effects on changes of the urine matabolic responses during carbohydrate loading diet to the long distance runners.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.545-550
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• 2011

We have synthesized a high electrically conductive 4-(2-(4-(acetylthio)phenyl)ethynyl)benzoic acid (APBA) with a conjugated aromatic structure as a bio fix linker, and then fabricated APBA self-assembled monolayer (SAM) with a self-assembly technique. The structure of the prepared APBA SAM was studied and electrochemical properties of APBA SAM immobilized with a ferrocene molecule were investigated. Also, we have examined the molecular orientation and oxidation-reduction redox characteristics of the mixed SAM consisting of APBA and butanethiol (BT) with a X-ray photo electron spectroscopy (XPS) and cyclicvoltammetry, respectively. Electrochemical activity of the mixed SAM was increased with increasing the mixed time. Especially, the maximum redox current was obtained at a mixed time of 36 hrs.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.588-591
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• 1991

S-adenosyl-L-methionine (SAM) is essential substrate for biological methylation reactions. The present work describes a reoptimized procedure of SAM preparation in laboratory scale by the method of yeast fermentation. The fermentation medium enriched with methionine and the culture conditions were reoptimized. The isolation steps consisted of 5 steps including extractions, precipitations, and chromatography. This improved procedure over original method provides relatively high yield of biologically active product within a 4 day-period.