• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.1954-1961
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• 2009

This paper describes the development of a three-phase line-interactive dynamic voltage restorer with hybrid detection method, which is composed of three H-bridge inverter modules and super-capacitors. The operational feasibility was verified through computer simulations with PSCAD/EMTDC software, and experimental works with a 3kVA prototype. The developed system can compensate the input voltage sag and interruption within 2ms. The maximum allowable duration of voltage interruption is about 4 seconds. The developed system can be effectively used to compensate the voltage interruption in the sensitive load, such as computer, communication devices, and automation devices, and medical equipment. The developed system has a simple structure to be easily implemented with commercially available components, and to be highly reliable in operation.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.38.2-38
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• 2001

Recent trend of increasing automated factories needs supply of high quality power from the utilities. Among the items of the power quality, voltage sag can be compensated by Dynamic Voltage Restorer(DVR). The key feature of the DVR is high response with less transient period to recover from the voltage sag due to the lightning or line-to-ground faults. In this paper we report that H controller is very premising for the practical application to the controller of DVR. Experiment al results shown in this paper was obtained by applying the control algorithm to 20 kVA DVR system. The experimental set consist s of IGBT - based three phase inverter and the TMS320C32- 60 DSP used for main processor of the control board. T$\infty$ simulate the 50% voltage ...

• The Journal of the Petrological Society of Korea
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• v.18 no.2
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• pp.79-91
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• 2009

Jurassic hornblende gabbo intrusives are distributed in Otanri, Chuncheon, and in Guwoonri, Hwacheon located in the northern part of Gyeonggi Massif. The intrusives composed mainly of amphiboles and plagioclase can be divided into two distinct rocks depending on the shape of amphiboles: (i) subspherical amphibole gabbro which has subspherical amphibole phenocryst as a major mafic phase(Sag); (ii) prismatic amphibole gabbro which has prismatic amphiboles as a principal mafic mineral(Pag). Subspherical amphiboles in Sag have higher Cr content and higher Mg($Mg+Fe^{2+}$) ratio relative to the prismatic amphiboles in Pag. This is indicative of conversion of pyroxene into amphibole with pyroxene pseudomorph. Oxygen isotopic results of plagioclase and amphibole separated from the hornblende gabbro suggest that theses minerals have experienced oxygen isotopic exchange with relatively heavy-$^{18}O$fluid for a long period, and magmatic fluid has been involved in the formation of subspherical amphiboles. Amphiboles in hornblende gabbro are composed of distinct species of pargasite, magnesiohornblende, actinolite, which formed at different stages.

• Tuberculosis and Respiratory Diseases
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• v.73 no.3
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• pp.151-161
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• 2012

Background: Adequate assessment and control of sedation play crucial roles in the proper performance of mechanical ventilation. Methods: A total of 30 patients with various pulmonary diseases were prospectively enrolled. The study population was randomized into two groups. The sedation assessment group (SAG) received active protocol-based control of sedation, and in the empiric control group (ECG), the sedation levels were empirically adjusted. Subsequently, daily interruption of sedation (DIS) was conducted in the SAG. Results: In the SAG, the dose of midazolam was significantly reduced by control of sedation (day 1, $1.3{\pm}0.5{\mu}g/kg/min$; day 2, $0.9{\pm}0.4{\mu}g/kg/min$; p<0.01), and was significantly lower than the ECG on day 2 (p<0.01). Likewise, on day 2, sedation levels were significantly lower in the SAG than in the ECG. Significant relationship was found between Ramsay sedation scale and Richmond agitation-sedation scale (RASS; $r_s$=-0.57), Ramsay Sedation Scale and Bispectral Index (BIS; $r_s$=0.77), and RASS and BIS ($r_s$=-0.79). In 10 patients, who didn't require re-sedation after DIS, BIS showed the earliest and most significant changes among the sedation scales. Ventilatory parameters showed significant but less prominent changes, and hemodynamic parameters didn't show significant changes. No seriously adverse events ensued after the implementation of DIS. Conclusion: Active assessment and control of sedation significantly reduced the dosage of sedatives in patients receiving mechanical ventilation. DIS, conducted in limited cases, suggested its potential efficacy and tolerability.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.363-367
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• 2013

The prevalence of Toxoplasma gondii infection in birds has epidemiological significance because birds are indeed considered as a good indicator of environmental contamination by T. gondii oocysts. In this study, the prevalence of T. gondii in 313 house sparrows in Lanzhou, northwestern China was assayed by the modified agglutination test (MAT). Antibodies to T. gondii were positive in 39 (12.46%) of 313 samples (MAT titer ${\geq}$ 1:5). Tissues of heart, brain, and lung from the 39 seropositive house sparrows were tested for T. gondii DNA, 11 of which were found to be positive for the T. gondii B1 gene by PCR amplification. These positive DNA samples were typed at 9 genetic markers, including 8 nuclear loci, i.e., SAG1, 5'- and 3'-SAG2, alternative SAG2, SAG3, GRA6, L358, PK1, c22-8 and an apicoplast locus Apico. Of them, 4 isolates were genotyped with complete data for all loci, and 2 genotypes (Type II variants; ToxoDB #3 and a new genotype) were identified. These results showed that there is a potential risk for human infection with T. gondii in this region. To our knowledge, this is the first report of T. gondii seroprevalence in house sparrows in China.

• Parasites, Hosts and Diseases
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• v.46 no.2
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• pp.105-108
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• 2008

Although the Korean isolate KI-1 of Toxoplasma gondii has been considered to be a virulent type I lineage because of its virulent clinical manifestations, its genotype is unclear. In the present study, genotyping of the KI-1 was performed by multilocus PCR-RFLP and microsatellite sequencing. For 9 genetic markers (c22-8, c29-2, L358, PK1, SAG2, SAG3, GRA6, BTUB, and Apico), the KI-1 and RH strains exhibited typical PCR-RFLP patterns identical to the type I strains. DNA sequencing of tandem repeats in 5 microsatellite markers (B17, B18, TUB2, W35, and TgM-A) of the KI-1 also revealed patterns characteristic of the type I. These results provide strong genetic evidence that KI-1 is a type I lineage of T. gondii.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.269-275
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• 1998

Anti-Neospora caninum antibody was detected in anti-Toxoplasma gondii positive and negative human sera by ELISA, western blot and immunofluorescence assay (IFA). Twelve cases out of 172 (6.7％) Toxoplasma-positive sera cross-reacted with both T. gondii and N. caninum antigens, and one out of 110 Toxoplasma-negative sera reacted with N. caninum antigen by ELISA. By western blot, all 12 sera reacted with T. gondii antigens with various banding patterns but specifically at 30 kDa (SAG 1), and 22 kDa （SAG2) bands. With N. caninum antigen, the number of reactive bands was reduced, however a 43 kDa band reacted in three cases in Toxoplasma-positive sera in addition to one in Toxoplasma-negative control sera. All sera of the Toxoplasma-positive group labeled surface membrane of T. gondii, but reacted differently with N. caninum. Fluorescence was detected in surface membrane, subcellular organelles, or both in N. caninum. And one case in the Toxoplasma-negative group also reacted with N. caninum strongly in subcellular organelles. This suggested that the antibody against N. caninum may be present in human sera although the positive rate was very low in this study. The possibility of human infection with N. caninum remains to be evaluated further.

• Parasites, Hosts and Diseases
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• v.53 no.3
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• pp.259-263
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• 2015

The increasing prevalence of Toxoplasma gondii infection in the human population in the Republic of Korea (= Korea) is due to various reasons such as an increase in meat consumption. However, the importance of cats in transmitting T. gondii infection through oocysts to humans has seldom been assessed. A total of 300 fecal samples of stray cats captured around Seoul from June to August 2013 were examined for T. gondii B1 gene (indicating the presence of oocysts) using nested-PCR. Fourteen (4.7%) of 300 cats examined were positive for B1 gene. Female cats (7.5%) showed a higher prevalence than male cats (1.4%). Cats younger than 3 months (5.5%) showed a higher prevalence than cats (1.5%) older than 3 months. For laboratory passage of the positive samples, the fecal suspension (0.2 ml) of B1 gene positive cats was orally inoculated into experimental mice. Brain tissues of the mice were obtained after 40 days and examined for the presence of tissue cysts. Two isolates were successfully passaged (designated KNIH-1 and KNIH-2) and were molecularly analyzed using the SAG5D and SAG5E gene sequences. The SAG5D and SAG5E gene sequences showed high homologies with the ME49 strain (less virulent strain). The results indicated the importance of stray cats in transmitting T. gondii to humans in Korea, as revealed by detection of B1 gene in fecal samples. T. gondii isolates from cats were successfully passaged in the laboratory for the first time in Korea.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.413-415
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• 2009

Genotyping of Toxoplasma gondii has been performed in 23 PCR positive blood samples from stray cats in Korea. We used 2 separate PCR-restriction fragment length polymorphism (RFLP) patterns of SAG2 gene, amplifying the 5' and 3' ends of the locus. The results revealed that all samples belonged to the type I clonal lineage. Although T. gondii organisms were not isolated from the samples, the results of the present study represent that stray cats with T. gondii infection should be seriously concerned in our environment. Adequate and continuous control programs of stray cats are needed to reduce the risk of transmission of T. gondii as a zoonotic infection threatening the public health.

• Parasites, Hosts and Diseases
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• v.52 no.3
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• pp.257-261
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• 2014

Toxoplasma 3 main clonal lineages are designated as type I, II, and III; however, atypical and mixed genotypes were also reported. This study was conducted for detection of Toxoplasma gondii genotypes in rats (Rattus rattus) in Riyadh region, Saudi Arabia. PCR test on T. gondii B1 gene was conducted on ELISA IgM positive samples for confirmation of the infection. However, genetic analysis of the SAG2 locus was performed to determine T. gondii genotypes using PCR-RFLP technique. PCR test on T. gondii B1gene showed that 22 (81.5%) out of the 27 ELISA IgM positive samples have T. gondii DNA. Genotypic analysis shows that, of the total 22 PCR positive samples, only 13 (59.1%) were of type II, 7 (31.8%) were of type III, and 2 (9.1%) were of an unknown genotype. It is obvious that the prevalence of both type II and III is high in rats. No reports have been available on T. gondii genotypes among rats in Riyadh region, and only little is known about its seroprevalence in rats. Future studies on T. gondii genotypes in rats using multi-locus markers is needed in Riyadh region, Saudi Arabia for better understanding of T. gondii pathogenesis and treatment in humans and animals.