• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.34.1-34.1
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• 2000

• Journal of the Microelectronics and Packaging Society
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• v.24 no.1
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• pp.9-16
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• 2017

Thermoelectric power generation (TEG) technology with high figure of merit (ZT) has become the need of the modern world. TEG is a potent technology which can tackle most of the environmental issues such as global warming, change in climatic conditions over the globe, and for burning out of various resources of non-renewable energy like as petroleum deposits and gasolines. Although thermoelectric materials generally convert the heat energy from wastes to electricity according to the theories Seebeck and Peltier effects yet they have not been fully exploited to realize their potential. Researchers are focusing mainly on how to improve the current ZT value from 1 to 2 or even 3 by various approaches. However, a higher ZT value is found to be difficult due to complex thermoelectric properties of materials. Hence, there is a need for developing materials with high figure of merit. Recently, various nanotechnological approaches have been incorporated to improve the thermoelectric properties of materials. In this review paper, the authors have performed a thorough literature survey of various kinds of TEG technology.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.540-545
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• 2010

Changes of electroencephalogram (EEG), mean arterial blood pressure (MAP) and heart rate under surgical anesthesia were investigated in medetomidine (MED) and tiletamine/zolazepam (ZT)-anesthetized dogs. To determine the level of surgical anesthesia, pedal withdrawal reflex was regularly tested after ZT injection. The first time point without pain response was regarded as the beginning of surgical anesthesia (SSA). After SSA, the first time point showing positive pain response was considered the end of surgical anesthesia (ESA). Comparing the control, an additional significant decrease of ${\delta}2$ and ${\alpha}2$ was observed at SSA. Comparing the control, ${\delta}2$ was significantly decreased at ESA. Significant reductions of MAP were observed at pre-ESA and ESA. Heart rate significantly decreased in all stages. These results suggest that ${\delta}2$ band power is a valuable parameter for correlating surgical anesthesia in dogs anesthetized with MED and ZT.

• Journal of the Korean Statistical Society
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• v.32 no.1
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• pp.11-20
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• 2003

Let｛Ｘt｝be an m-dimensional linear process of the form (equation omitted), where｛Zt｝is a sequence of stationary m-dimensional weakly associated random vectors with EZt = O and E∥Zt∥$^2$＜$\infty$. We Prove central limit theorems for multivariate linear processes generated by weakly associated random vectors. Our results also imply a functional central limit theorem.

• Korean Journal of Applied Biomechanics
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• v.30 no.1
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• pp.27-35
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• 2020

Objective: The purpose of this study was to investigate the influence of clubhead velocity through regression analysis on the magnitude and time difference of the forward-backward, mediolateral, and vertical ground reaction peak forces generated by force plate during golf swing. Method: 16 subjects (age: 20.5±4.2 yrs, height: 176.0±5.4 cm, weight: 77.8±5.9 kg, handy: 2.4±1.7) who is elite golf player in high school and university, participated in this study. The study method adopted three-dimensional analysis with 8 cameras and ground reaction force measurement with two force plate. The analysis variables were clubhead velocity, and ground reaction analysis variables set four events in each graph based on the peak forces commonly generated in Fx, Fy, and Fz graphs of the ground reaction data during the golf swing. Results: As a result of analyzing the influence of ground reaction magnitude difference on clubhead velocity, the influence on clubhead velocity was ym4, zm1, xm4, zm2. The larger ym4, xm4, zm1, the fasterthe clubhead velocity, but the smallerthe zm2, the faster the clubhead velocity. And in time difference, the influence on the clubhead velocity was in the order of xt4, zt1, zt3. The shorter xt4, zt1, zt3 showed faster clubhead velocity. Conclusion: The leftfoot played a leading role in increasing the velocity of the clubhead. Although the result was caused by the interaction of the right foot and the left foot during the swing, the role of the left foot is relatively large.

• Journal of Powder Materials
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• v.22 no.4
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• pp.254-259
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• 2015

$Bi_2Te_3$ related compounds show the best thermoelectric properties at room temperature. However, n-type $Bi_2Te_{2.7}Se_{0.3}$ showed no improvement on ZT values. To improve the thermolectric propterties of n-type $Bi_2Te_{2.7}Se_{0.3}$, this research has Cu-doped n-type powder. This study focused on effects of Cu-doping method on the thermoelectric properties of n-type materials, and evaluated the comparison between the Cu chemical and mechanical doping. The synthesized powder was manufactured by the spark plasma sintering(SPS). The thermoelectric properties of the sintered body were evaluated by measuring their Seebeck coefficient, electrical resistivity, thermal conductivity, and hall coefficient. An introduction of a small amount of Cu reduced the thermal conductivity and improved the electrical properties with Seebeck coefficient. The authors provided the optimal concentration of $Cu_{0.1}Bi_{1.99}Se_{0.3}Te_{2.7}$. A figure of merit (ZT) value of 1.22 was obtained for $Cu_{0.1}Bi_{1.9}Se_{0.3}Te_{2.7}$ at 373K by Cu chemical doping, which was obviously higher than those of $Cu_{0.1}Bi_{1.9}Se_{0.3}Te_{2.7}$ at 373K by Cu mechanical doping (ZT=0.56) and Cu-free $Bi_2Se_{0.3}Te_{2.7}$ (ZT=0.51).

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.153-159
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• 1987

Adsorption and desorption characteristics of $^{42}K$ and $^{45}Ca$ were studied by making use of the natural zeolite, bentonite, and vermiculite. The work included that the fittness tests for the Freundlich and the Langmuir adsorption isotherms and desorption of the radionuclides from adsorbents by extracting with $NH^+_4$ ($1N-NH_4OAc$). The adsorption by the radionuclides are fitted well with both of the adsorption equations. The Langmuir adsorption maximum of $^{42}K$ is higher than that of $^{45}Ca$ by the zeolite and bentonite except vermiculite, and the values of $^{42}K$ decrease in the order of Zeolite (Zt)>Bentonite (Bt)>Vemiculite (Vt). As for $^{45}Ca$, the maximum adsorption values decrease in the order of Bt>Vt>Zt. The ionic radii of K and Ca seem to be closely related with fixation in the cavity of the zeolite that adsorb more $^{42}K$ than $^{45}Ca$. The smaller ionic size of Ca seems to be resulted in the lower adsorption of $^{45}Ca$ by the zeolite because Ca could leave easily from the cavity. Ionic size of K, however, seems to be similar with size of the cavity. $^{45}Ca$ adsorption by the bentonite, on the other hand, show higher adsorption than $^{42}K$. The higher charge density of the divalent cations than those of the monovalent cations seems to be the main consideration. For the retention strength of the adsorbed $^{42}K$ and $^{45}Ca$ by the adsorbents, a comparison is made by use of the Langmuir constant(k). The results indicated that the constant values for K are smaller than those of Ca in all the adsorbents. It seems that the smaller values of the constant, the weaker retention strength. For $^{42}K$, the percentage of desorption decrease in the order of Zt>Bt>Vt, but in the case of $^{45}Ca$, it decreases in the order of Vt>Zt>Bt. The results show that the weaker binding strength as represented by small value of the Langmuir constant, the higher percentage of the removal except fixing preferably $K^+$ by the vemiculite. In conclusion, the zeolite could adsorb much more $^{42}K$ and remove it more than others. For $^{45}Ca$, the bentonite could adsorb more and desorb less than others.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.209-218
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• 2006

This study was to evaluate microcystin production by two strains of cyanobacteria (Microcystis aeruginosa and Planktothrix agardhii) in response to three different levels of direct (0,4,8 inds.) or indirect (0,25, 50% of zooplankton culture media filtrate) exposures to zooplankton (Daphnia magna and Moina macrocopa). The cell biomass and intracellular microcystin (MC) were measured everyday. The survival rates of zooplankton were evaluated for daily intervals for the direct exposure. The intracellular MC produced peaked on the day 3 or 4, and then decreased over the both exposure experiment. In the direct experiment, the MC values were significantly different among the control and zooplankton treatments (ZT; repeated measures-ANOVA: P< 0.039). The MC contents of P. agardhii strain (No.204) were significantly higher (Tukey test, P< 0.082) in ZT2 (8 inds.) than in ZT2 (4 inds.). On the peak day, the intracellular MC exposed to both zooplanktons was significantly higher than the control (One-way ANOVA, P< 0.021). Higher zooplankton survivals were observed in the M. aeruginosa strain (No. 111) rather than in high toxic P. agardhii strain. In the indirect experiment, the intracellular MC of the M. aeruginosa strain was significantly different among the control and zooplankton culture media filtrate (ZCMF)treatments (rm-ANOVA: P<0.004), The MC exposed ZCMF2 (50%) were significantly higher than in ZCMFI (25%: Tukey test, P< 0.025) for both strains. This study strongly supports the induced-defensive MC production of potentially toxic cyanobacteria in response to the presence of zooplankton.

• Journal of Veterinary Clinics
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• v.25 no.6
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• pp.488-493
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• 2008

This study compared the effect of injectable combinations of anesthetics on each of the fluorescein angiographic phases in order to determine the most useful anesthetic combination for the procedure. Acepromazineketamine (AK), xylazine-ketamine (XK), diazepam-ketamine (DK) and zolazepam-tiletamine (ZT) group were administered randomly to 8 dogs with a two-week interval between different combination doses. The vital signs including the heart rate and arterial pressure were measured before anesthesia and every five minutes during anesthesia. Serial angiographic images were obtained after injecting a sodium fluorescein dye (25 mg/kg) and the onset time of arterial phase (AP), arteriovenous phase (AVP), early venous phase (EVP) and late venous phases (LVP) were recorded. The onset time of the AP, AVP and EVP were significantly slower in the AK and XK groups than in the DK and ZT groups. The total duration of the AP and AVP in the AK group was significantly longer than those in the ZT group. The heart rates were significantly higher in the DK and ZT groups. The arterial pressure was significantly higher in the AK and XK groups (p<0.05). There were significant differences in each angiographic onset time and duration depending on the changes in the heart rates and arterial pressure. The AK and XK groups showed a long angiographic duration allowing an accurate evaluation. Overall, it is believed that AK and XK are more useful for performing fluorescein retinal angiography than DK and ZT.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.02a
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• pp.165-165
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• 1999