• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1786-1795
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• 2015

It is common practice to identify the insulation faults of GIS through monitor the contents of SF₆ decomposed components. Partial discharges (PD) could lead to the decomposition of SF₆ dielectric, so new reactions usually occur in the mixture of the newly decomposed components including traces of H₂O and O₂. The new reactions also cause the decomposed components to differ due to the different amounts of H₂O and O₂ even under the same strength of PD. Thus, the accuracy of assessing the insulation faults is definitely influenced when using the concentration and corresponding change of decomposed components. In the present research, a needle-plate electrode was employed to simulate the PD event of a metal protrusion insulation fault for two main characteristic components SO₂F₂ and SOF₂, and to carry out influence analysis of trace H₂O and O₂ on the characteristic components. The research shows that trace H₂O has the capability of catching an F atom, which inhibits low-sulfide SF_x from recombining into high-sulfide SF₆. Thus, the amount of SOF₂ strongly correlates to the amount of trace H₂O, whereas the amount of SO₂F₂ is weakly related to trace H₂O. Furthermore, the dilution effect of trace O₂ on SOF₂ obviously exceeds that of SO₂F₂.

• Journal of Energy Engineering
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• v.24 no.2
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• pp.129-143
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• 2015

Increasing concerns on climate change and energy security accelerated policies to reduce green-house gas emission, especially from the transportation sector. Electric vehicle (EV) has been on the spotlight to deal with such environmental issue and V2G (Vehicle-to-Grid) technology began to draw attentions as an alternative to reduce ownership costs while contributing to an efficient and decentralized power grid. This study conducts a scenario analysis on total cost of ownership of EV under V2G scheme and compare with non-V2G EV and Internal Combustion Engine (ICE) vehicle. As result, V2G service is expected to provide an annual average profit of $210 to EV users willing to reverse flow its residual power in the battery. The profit from V2G service leaves a margin of $4,530 over operational lifetime, compared with $2,420 cost of charge for non-V2G EV. In summary, total cost of ownership of V2G-capable EV was 6.2% less than non-V2G EV and 10.2% higher than ICE vehicle. The results confirm a comparative economic advantage of operating EV under V2G scheme. Increased number of EVs with V2G service has shown to provide positive effects to power industry for valley filling in load distribution, thus, favorably increasing the overall economic feasibility.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.4
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• pp.406-412
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• 2019

In this paper, we propose two algorithms for classifying services with similar delay characteristics into three classes and allocating radio resources according to priority in LTE-A system where H2H and M2M services coexist. The first is to allocate resources from the higher priority class to the lower priority class, and each class gives priority to H2H over M2M, and the other is to give priority to H2H regardless of delay characteristics except for the class with the highest priority. The RA success probability was analyzed according to the access rate(${\alpha}$) of M2M devices in each class. In comparison with the conventional systems, it was improved from 0.5 to 0.52 for ${\alpha}_{2M}=0.05$ in two classes. In the three classes, the success probability was slightly increased from 0.5 to 0.57 for ${\alpha}_{2M}={\alpha}_{3M}=1$ and from 0.5 to 0.58 for ${\alpha}_{2M}=0.5$ and ${\alpha}_{3M}=0.1$. Although 6 services are considered in the proposed scheme, the RA success probability is almost similar to the previous scheme because the average arrival rate of H2H of each class is set to the same.

• Journal of the Korean Chemical Society
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• v.16 no.2
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• pp.80-83
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• 1972

The activity change of lysozyme resulted from its exposure to $Ti-H_2O_2$system in aqueous liquid at room temperature and to ${\gamma}$-irradiation in ice at $195^{\circ}K$ has been measured at room temperature with a Cary-14 spectrophotometer. The enzymatic activity of lysozyme which had been added to a previously flow-mixed solution of $TiCl_3$ and $H_2O_2$ (System I) was compared with the activity of a lysozyme-$H_2O_2$ solution after flow-mixing with $TiCl_3$ (System II), considering the differences between these two activity changes as the extent of the enzymatic inactivation by the involvement of OH radical reaction. The fraction of lysozyme inactivated by OH radical in the system containing 0.0025 M $TiCl_3-0.1M$ $H_2O_2$ (ph 3.5) was 13%, When the $TiCl_3$ concentration is double (pH 3.0), the fraction of enzyme inactivated increases to 36%. The activity of the system containing 0.025 M $TiCl_3-0.1$ M $H_2O_2$ (pH 1.5) was essentially zero. The results seem to support the previos view that the production of OH radical should be proportional to $TiCl_3$ concentration when $H_2O_2$ is present in excess. Increase in the extent of inactivation found in system I with increasing $TiCl_3$ concentration may be due to a pH effect. $H_2O_2$ seems to be less effective than $TiCl_3$ in the inactivation. 1% lysozyme solution, when ${\gamma}$-irradiated with a total dose of 3M rads, loses about 20% of its activity. Lowering of temperature also was found to yield a reduction in enzymatic activity.

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.9-13
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• 2006

Anaplasma phagocytophilum major surface protein-2 (Msp2 or p44) is the immunodominant outer membrane protein of the bacterium. Recently, we disclosed that Msp2 was an A. phagocytophilum adhesin for binding to host neutrophils and HL-60 cells, probably mediated by attachment to platelet selectin glycoprotein ligand-1 (PSGL-1). In this study, we further elucidated that Msp2 bound to PSGL-1/FucT IV-transfected BJAB but not nontransfected BJAB cells. Binding of recombinant Msp2 or cell (lee bacteria to the surface of PSGL-1/FucT IV-transfected BJAB cells was significantly higher than to nontransfected BJAB cells (p<0.01 and p<0.01). Also, Msp2 monoclonal antibody and soluble recombinant Msp2 as antagonist led to concentration-dependent reductions in A. phagocytophilum adhesln (p<0.05 and p<0.01) to transfected BJAB cells. Thus, we conclude that Msp2 of. A. phagocytophilum acts as an adhesin by which the bacterium binds to PSGL-1 on host neutrophils and myeloid cells.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.457-464
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• 1995

Hela cells, a transformed human epithelial cell line, attach to various substrata but subsequent spreading is specific to collagen or gelatin. The spreading is initiated by the activation of phospholipase $A_2$ (PLA$_2$) which produces arachidonic acid (AA) as a consequence of cell surface collagen receptor clustering. This study examines the mechanism of PLA$_2$activation and which phospholipids are hydrolyzed by PIA$_2$ to release AA in response to Hela cell adhesion to a gelatin substratum. The levels of phosphatidyicholine decreases, among various phospholipids, during attachment and spreading of Hela cells. Lysophosphatidyicholine Is the only lysophospholipids formed during ileLa cell adhesion indicating that clustered collagen receptors activate PLA$_2$to hydrolyze posphatidylcholine to AA and lysophosphatidylcholine. Among various molecular entitles which are known to regulate PLA$_2$ activation, we have previously shown that PLA2 activation is not mediated by either changes in $Ca_2$+ levels, alkalinization of cytoplasmic p11, or activation of protein hinase C. It is also likely that PIA2 activation is not mediated by either pertussis or cholera toxinsensitive G proteins as those toxins do not affect both AA release and cell spreading.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.85-92
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• 2013

PURPOSES: The purpose of this paper is to estimate expected effects on traffic operational and economic aspects of 2+1 roads application in Korea. METHODS : Micro simulation study using VISSIM 5.0 was used to analyze the operation efficiency of 2+1 roads compared to two-lane highways and four-lane highways. Some scenarios for various traffic volumes were set up in order to analyze the effect of 2+1 roads under various traffic situations. Also imaginary road networks were set up for each type of roads. The MOEs to measure the operation efficiency were selected with average travel speed and delay. For analyzing economic effect of 2+1 roads, construction cost of a specific imaginary 2+1 road was compared to construction cost of a four-lane highway with same conditions. RESULTS: The results of study show that a 2+1 road is more effective with 19 percents higher average travel speed and 39 percents lower average delay than a two-lane highway. In the economic analysis, construction costs to construct a 2+1 road are saved as approximately 26.4~40.7 percents when compared to construction of four-lane highway. CONCLUSIONS: It can be concluded that 2+1 roads can improve the traffic operational level of service for two-lane highways and 2+1 roads can be applied as an effective design alternative for higher-volume two-lane highways in Korea.

• Annals of Clinical Neurophysiology
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• v.25 no.1
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• pp.32-37
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• 2023

Background: Type 2 diabetic mellitus (T2DM) is an emerging global pandemic which is associated with lots of co-morbidities and reported vascular dysfunctions. T2DM associated vascular dysfunctions leads to vasculopathy in the form of altered peripheral vascular dynamics. Cold stress test (CST) is a reliable sympathetic reactivity test used for assessing vascular dysfunctions. In this study we are trying to quantify vascular dysfunctions in T2DM patients non invasively by various parameters of photoplethysmography (PPG) of cold stress test. Methods: Case control study had done in referral health center AIIMS, Raipur. Parameters are recorded by finger-PPG before, during and after CST (1 min) in 2 groups, control (n = 20 healthy volunteers) and case (n = 20 diagnosed T2DM patients). Results: Due to cold stress, PPG parameter peak amplitude was significantly decreased in both healthy and T2DM groups (p <0.001 and p <0.001, respectively). However, recovery trend of amplitude was significantly slow in T2DM compared to healthy subjects. Another PPG parameter peak to peak interval was significantly higher in healthy group compared to T2DM patients. Conclusions: This study showed that T2DM patients has significant deranged pulse volume parameters like amplitude and peak to peak interval can be used to objectively quantify the vasculopathy in T2DM patients by using sympathetic reactivity to cold stress.

• English Language & Literature Teaching
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• v.18 no.1
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• pp.115-132
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• 2012

In order to confirm ecological validity of D$\ddot{o}$rnyei's second language motivational self, the present study investigated 495 South Korean secondary school students' L2 learning motivation and motivated behavior by using a questionnaire survey. The participants' ideal L2 self, ought-to L2 self, integrativeness, and instrumentality were examined and compared to identify which motivational factor had the most effect on their motivated L2 learning behavior. Among Korean secondary school students, the concept of integrativeness was replaced with the ideal L2 self as a more appropriate concept for understanding Korean secondary school students' L2 learning motivation. As for instrumentality, promotional aspects demonstrated a significant correlation with both the ideal and ought-to L2 selves, whereas preventional aspects showed a relatively high correlation with the ought-to L2 self. The ideal L2 self had the most impact on the motivated behavior, and the ideal L2 self and ought-to L2 self reflected the students' different motivational characteristics. It is suggested that D$\ddot{o}$rnyei's (2005, 2009) L2 motivational self system can be a better psychological model than Gardner's (1985) socio-educational model for understanding Korean secondary school students' L2 learning motivation.

• Korean Journal of Materials Research
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• v.17 no.10
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• pp.526-531
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• 2007

The sintering behavior and electrical property of $Ce_{0.8}Gd_{0.2}O_{1.9}$ ceramics were investigated with the iron oxide concentration ranging from 0 to 5 mol%. Both the sintered density and grain size were found to increase up to 2 mol% $Fe_2O_3$, and then to decrease with further additions. At a higher $Fe_2O_3$ content above 3 mol%, grain size decreased by a pinning effect induced by different shape grains. The electrical conductivity was also increased with increasing $Fe_2O_3$ content up to 2 mol%. Total conductivity of 2 mol% $Fe_2O_3-added$ specimen showed the maximum conductivity of $2{\times}10^{-2}{\Omega}{\cdot}cm^{-1}$ at $500^{\circ}C$. The addition of $Fe_2O_3$ was found to promote the sintering properties and electrical conductivities of $Gd_2O_3-dope\;CeO_2$.