• Journal of Korea Technology Innovation Society
• /
• v.17 no.1
• /
• pp.174-194
• /
• 2014

Collaborative technology development is now one of the most significant modes of activity in the global scientific community. However, the international cooperation of science and technology simultaneously provides opportunities and challenges, and the results of global R&D collaboration can be positive or negative as the cooperation conditions of the parties may be different according to the types or characteristics of the participants and the pattern, purpose, and motivation of cooperation. In order to minimize the risk and improve the performance of cooperation, more comprehensive as well as micro-level research is needed. This study investigates a case of successful collaborative R&D conducted by several firms, universities, and public research organizations in both Korea and the U.S.A. The aim of this study is to identify the factors of successful R&D collaboration.

• Journal of Powder Materials
• /
• v.12 no.2 s.49
• /
• pp.117-121
• /
• 2005

Platinum catalysts for the DMFC (Direct Methanol Fuel Cell) were impregnated on several carbon supports and their catalytic activities were evaluated with cyclic voltammograms of methanol electro-oxidation. To increase the activities of the Pt/C catalyst, carbon supports with high electric conductivity such as mesoporous carbon, carbon nanofiber, and carbon nanotube were employed. The Pt/e-CNF (etched carbon nanofiber) catalyst showed higher maximum current density of $70 mA cm^{-2}$ and lower on-set voltage of 0.54 V vs. NHE than the Pt/Vulcan XC-72 in methanol oxidation. Although the carbon named by CNT (carbon nanotube) series turned out to have larger BET surface area than the carbon named by CNF (carbon nanofiber) series, the Pt catalysts supported on the CNT series were less active than those on the CNF series due to their lower electric conductivity and lower availability of pores for Pt loading. Considering that the BET surface area and electric conductivity of the e-CNF were similar to those of the Vulcan XC-72, smaller Pt particle size of the Pt/e-CNF catalyst and stronger metal-support interaction were believed to be the main reason for its higher catalytic activity.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.4
• /
• pp.924-928
• /
• 2006

This study was undertaken to determine the effects of Zusanli(ST 36) electro-acupuncture(EA) on the small intestinal motility in rat. The motor activity of the rat small intestine was evaluated by intestinal transfortation rate. Changes in the motility in vivo of ileum was measured before and 10 minutes after acupuncture. In order to examine whether EA effect was affected by stimulated duration and left or right sides of ST36 acupoint, both of the difference effects of left or right sides on acupoints of ST 36 and the stimulated duration of 10, 20, 30 min. were investigated on the motility in vivo of ileum. These results suggest that effect of Zusanli(ST36) for increasing the small intestinal motility should stimulate more than 20 minutes, left ST36 EA has stronger effect than right ST36 EA.

• The Korea Journal of Herbology
• /
• v.30 no.1
• /
• pp.19-24
• /
• 2015

Objectives : This study was carried out to know the necessity of freezing and boiling process of Gastrodiae Rhizoma. Also we need to evaluate Gastrodia elata floral axis as a product ingridients. Methods : Frozen Gastrodiae Rhizoma (GF1, GF2) and Gastrodia elata floral axis (GFA) were prepared. They were divided into samples (GF1 : frozen at the freezer, GF2; frozen and boiled for 10 hours, GFA; dried at 7 $0^{\circ}C$ for 120 hours) for experiment. They were extracted using water, freeze dried and powdered. And we analyzed proximate compositions, free sugars, gastrodin, p-hydroxybenzyl alcohol and p-hydroxybenzyl aldehyde content, phenolic and flavonoid, electron donating ability and nitrate scavenging activity and antioxidant activity. Results : In moisture, crude ash, fructose, glucose, sucrose, p-Hydroxybenzyl alcohol GF2 showed lower level than GF1. But GF2 showed higher content than GF1, in crude fat (0.8% > 0.19%), gastrodin ($8.84{\pm}0.58%$ > $4.18{\pm}0.73%$), and p-hydroxybenzyl aldehyde ($2.45{\pm}0.26%$ > $2.07{\pm}0.16%$) content, phenolic ($9.98{\pm}0.07%$ > $3.35{\pm}0.03%$) and flavonoid ($3.01{\pm}0.06%$ > $1.09{\pm}0.04%$) content, electro donating ability ($15.21{\pm}6.51%$ > $10.44{\pm}4.78%$), nitrate scavening activity ($20.43{\pm}5.30%$ > $13.62{\pm}5.78%$). GFA has a relatively lower key indicators component, but has a enough impact on antioxidant effect in phenolic ($11.85{\pm}0.08%$) and flavonoid content ($1.45{\pm}0.03%$), electron donating ability ($18.58{\pm}9.06%$) and nitrate scavenging activity ($19.41{\pm}9.90%$). Conclusions : In the view of proximate compositions, free sugars, functional component and antioxidant activity, the results indicated that boiling process is effective for the frozen Gastrodiae Rhizoma. And Gastrodia elata floral axis has a significantly functional components and antioxidant activity.

• Physical Therapy Korea
• /
• v.15 no.2
• /
• pp.30-37
• /
• 2008

Anticipatory postural adjustments are pre-planned by the central nervous system (CNS) before the activation of agonist muscles in the limbs, and minimize postural sway. Most previous studies on this topic have focused on upper-limb movement, and little research has been conducted on lower-limb movement. The purpose of this study was to investigate the recruitment order of left and right trunk muscles during limb movement. Fifteen healthy subjects (10 male, 5 female) were enrolled. Electro-myographic signals were recorded on the muscles of: (1) deltoid, lumbar erector spinae, latissimus dorsi and internal oblique during shoulder flexion, (2) rectus femoris, rectus abdominis, external oblique and internal oblique during hip flexion. During right upper limb flexion, the onset of left erector spinae muscle and left internal oblique muscle activity preceded the onset of right deltoid by 8.09 ms and 19.83 ms, respectively. But these differences were not significant (p>.05). A similar sequence of activation occurred with lower limb flexion. The onset of left internal oblique muscle activity preceded the onset of right rectus femoris muscle by 28.29 ms (p<.05). The onset of right internal oblique muscle activity preceded the onset of left rectus femoris muscles by 23.24 ms (p<.05). The internal oblique muscle was the first activated during limb movement. Our study established the recruitment order of trunk muscles during limb movement, and explained the postural control strategy of the trunk muscles in healthy people. We expect that this study will be used to evaluate patients with an asymmetric recruitment order of muscle activation due to impaired CNS.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.5
• /
• pp.529-534
• /
• 2009

Physiological activities of mistletoe extracts were examined. Total polyphenol contents, electro-donating ability, SOD-like activity, nitrite-scavenging ability and tyrosinase of mistletoe extracted with water, 50%, and 100% ethanol were determined. Total polyphenol contents of powder extracts were higher than slice extracts. EDAs showed over 90% at powder extracts. Especially mistletoe extracts with 50% ethanol were higher than water extracts. SOD-like activities of water, 50% and 100% ethanol extracts of all samples were $23.71{\sim}33.4%$ lower than those of 1.0% and 0.1% L-ascorbate solutions. Nitrite-scavenging activities at pH 1.2 were the most effective in water, 50% and 100% ethanol extracts. The results will be useful for understanding the physiolosical activities of mistletoe extracts.

• Journal of the Korean Electrochemical Society
• /
• v.11 no.3
• /
• pp.141-146
• /
• 2008

Electrocatalytic activities and stabilities of Pt supported on Sb-doped $SnO_2$ (ATO) were examined for ethanol oxidation reactions. Pt colloidal particles were deposited on ATO nanoparticles (Pt/ATO) and the prepared electrocatalysts were characterized by X-ray diffraction, transmission electron microscopy (TEM), and cyclic voltammetry. Electrochemical activity of the Pt/ATO for ethanol electro-oxidation was compared to those of Pt supported on carbon (Pt/C) and commercial PtRu/C. The activitiy of the Pt/ATO was much higher than those of the Pt/C and commercial PtRu/C. The Pt/ATO exhibited much higher electrochemical stabilities than the Pt/C in 0.5M ${H_2}{SO_4}$ and in 0.5M ${H_2}{SO_4}$/1M ${C_2}{H_5}OH$. According to TEM, the growth rate of Pt particles was lower in the Pt/ATO than it was in the Pt/C. The ATO nanoparticle appears to be a promising support material that promotes electrochemical reactions and stabilizes catalyst particles in direct ethanol fuel cell.

• Korean Journal of Applied Biomechanics
• /
• v.31 no.1
• /
• pp.72-78
• /
• 2021

Objective: The purpose of this study was to investigate relations and effectiveness about mountain climbling exercise with different level of support surfaces by analyzing heart rate and EMG data. A total of 10 male college students with no musculoskeltal disorder were recruited for this study. Method: The biomechanical analysis was performed using heart rate monitor (Polar V800, Polar Electro Oy, Finland), step-box, exercise mat, and EMG device (QEMG8, Laxtha Inc. Korea, sampling frequency = 1,024 Hz, gain = 1,000, input impedance > 1012 Ω, CMRR > 100 dB). In this research, step-box were used to create different surface levels on the upper body (flat surface, 10% of subject's height, 20% of subject's height, and 30% of subject's hight). Based on these different conditions, data was collected by performing mountain climbing exercise during 30 seconds. Subjects were given 5 minutes of break to prevent muscular fatigue after each exercise. For each dependent variable, a one-way analysis of variance with repeated measures was conducted to find significant differences and Bonferroni post-hoc test was performed. Results: The results of this study showed that exercise intensity was reduced statistically as increased surface level on the upper body. Muscle activity of the upper rectus abdominis and biceps femoris for 30% of surface level was significantly higher than the corresponding values for flat surface. However, the opposite was found in the rectus femoris. In general, muscle activity of the lower rectus abdominis, erector spinae, external oblique abdominis, and gluteus maximus increased when surface level increased, but the differences were not significant. Conclusion: As a result, the increase in surface level of the body would change muscle activity of the upper body, indicating that different surface level of the upper body may cause significant effect on particular muscles to be more active during mountain climbing exercise. Based on results of this study, it is suggested to set up an appropriate surface level to target particular muscle to expect an effective training. It is also important to set adequate surface levels to create an effective training condition for preventing exercise injuries.

• Journal of Electrochemical Science and Technology
• /
• v.10 no.4
• /
• pp.416-423
• /
• 2019

A novel non-enzymatic oxalic acid (OA) sensor based on the platinum/carbon black-nickel-reduced graphene oxide (Pt/CBNi-rGO) nanocomposite is reported. The nanocomposites were prepared by the ethylene glycol reduction method. Their morphology and chemical composition were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). The results clearly demonstrated the formation of the Pt/CB-Ni-rGO nanocomposite. The electrocatalytic activity of the Pt/CB-Ni-rGO electrode was investigated by cyclic voltammetry. It was determined that the appropriate amount of Pt enhanced the catalytic activity of Pt for oxalic acid electro-oxidation. Moreover, the modified electrode was determined to be highly selective for oxalic acid without interference from compounds commonly found in urine including uric acid and ascorbic acid. The chronoamperometric signal gave a wide linearity range of 20 μM-60 mM and the detection limit (3σ) was found to be 2.35 μM. The proposed method showed high selectivity, stability, and good reproducibility and could be used with micro-volumes of sample for the detection of oxalic acid. Finally, the oxalic acid content in artificial and control urine samples were successfully determined by our proposed electrode.

• Korean journal of applied entomology
• /
• v.32 no.3
• /
• pp.265-270
• /
• 1993

The German cockroach(Blattelia germanica) population~ were successIVely selected with ch\orpyrifos and permethrin during the six generations. The resulting resistant $R_{chtorpenfos}$(Rc) and $R_{permethnn}$(Rp) stra.ins were studied to investigate the esterase activity by spectrophotometer, filter parper test, and electrophoresis. Esterase-$\alpha$ activities by filter paper test showed 2.65 and LBZ times higher in the Rc and Rp strains than the susceptible strain, respectively. ln the spectrophoLometer method, the esterase activit18s to $\alpha$-and $\beta$-naphthyl acetate were increased 2.34 and 5.28 times in the Rc than susceptible strain, and 1.48 and 2.92 times in the Rp Limn susceptible stram, respectlvely. Zymogram patterns of eslerase isozyme by agarose gel electrophoresis showed totally five bands. The Rc and Rp strains showed two additive bands as, Est-2 and Est-3, which were not shown in the susceptible strain. but the Rp strain dId not show Est-5 bands which was COlumon in the Rc and susceptible strams.