• Journal of Power Electronics
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• v.17 no.1
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• pp.305-313
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• 2017

A novel interference isolation method is proposed by using several designed coils in capacitive power transfer systems as isolation impedances. For each designed coil, its stray parameters such as the inter-turn capacitance, coil resistance and capacitance between the coil and the core, etc. are taken into account. An equivalent circuit model of the designed coil is established. According to this equivalent circuit, the impedance characteristic of the coil is calculated. In addition, the maximum impedance point and the corresponding excitation frequency of the coil are obtained. Based on this analysis, six designed coils are adopted to isolate the interference from power delivery. The proposed method is verified through experiments with a power carrier frequency of 1MHz and a data carrier frequency of 8.7MHz. The power and data are transferred parrallelly with a data carrier attenuation lower than -5dB and a power attenuation on the sensing resistor higher than -45dB.

• The Journal of the Korean Society for Microbiology
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• v.10 no.1
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• pp.19-24
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• 1975

Anaerobic bacteria are the major residents of human skin and mucous membrane. The importance, as opportunistic pathogens, of anaerobic bacteria are well recognized because of more population. with decreased defense against bacterial invasion due to chemotherapy, rediation therapy, extensive surgical operation etc. are dealt at hospitals. An analysis of the anaerobe isolation results at Yonsei University Medical Center during the January 1974-May 1975 period was made and the following results were obtained. 1) From 118 patients 146 strains of anaerobes were isolated. Among these 81.3% were nonsporforming anaerobes. Most frequently isolated anaerobes were Pc. asaccharolyticus, Ps. anaerobius, Ps. intermedius, B. fragilis and Cl. perfringens. 2) Anaerobes were frequently isolated from wound, female genital, intraabdominal, and pleuropulmonary specimens. Fewer anaerobes were isolated from blood, spinal fluid and liver specimens. 3) The ratio of anaerobe isolation to total bacteria isolation were; liver 66.7%, intraabdominal 33.3%, pleuropulmonary 28.9%, spinal fluid 5.0% and blood 4.2%. 4) Among the 118 anaerobe isolated patients, 48.3% yielded anaerobes only and rest of them yielded anaerobes together with aerobes. 5) Most of the gram-positive anaerobes were susceptible to the antibiotics tested. Exception was to tetracycline to which appreciable number showed resistance. It was noteworthy that only 48% of B. fragilis was susceptible to tetracycline.

• Food Science of Animal Resources
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• v.40 no.1
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• pp.21-33
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• 2020

This study aimed to determine the current prevalence, serovar distribution and antimicrobial resistance rate and patterns of nontyphoid Salmonella (NTS) in slaughter sheep and their edible offal. While filling the gap of up to date related information in Turkey, data presented is also of significance since contamination of ovine meat, its products and offal with this pathogen is threat to public health due to their considerably high consumption rates in our country. Current NTS carriage in 200 apparently healthy slaughter sheep by ISO 6579:2002, 6579:2002/A1:2007 standard bacteriology (ISO) was 5% (10/200) (4 fecal content - 2%, 3 mesenterial lymph node - 1.5%, 3 kidney - 1.5%) out of 1,400 samples (0.7%), with no isolation from carcass, liver, gallbladder, spleen. Real-time PCR was in substantial agreement to ISO in confirming Salmonella-suspect isolates (Relative Trueness: 93.6%). S. Newport (40%) was the predominant serovar, followed by the second prevalent serovars as S. Typhimurium and S. Kentucky (20%), and by S. Umbilo and S. Corvallis (10%). Four and 6 out of 10 NTS isolates were susceptible (40%) and resistant (60%) to 18 antimicrobials, respectively. S. Typhimurium isolates were multidrug resistant (MDR) to tigecycline and sulphamethoxazole/trimethoprim, with one also resistant to cefepime. S. Corvallis was MDR to ampicillin, ciprofloxacin, norfloxacin and pefloxacin. The predominance of S. Newport and first isolation of S. Corvallis in sheep in the world; first time isolations of Newport, Kentucky, Corvallis, Umbilo serovars from sheep in Turkey; and high antimicrobial resistance rates obtained in majority of the isolates highlights study findings.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1646-1649
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• 2012

The $O_2$ annealing technique has considerably suppressed the leakage current of GaN power devices, but this forms NiO at Ni-based Schottky contact with increasing on-resistance. The purpose of the present study was to fabricate 1.5 kV GaN Schottky barrier diodes by improving $O_2$-annealing process and GaN buffer. The proposed $O_2$ annealing performed after alloying ohmic contacts in order to avoid NiO construction. The ohmic contact resistance ($R_C$) was degraded from 0.43 to $3.42{\Omega}-mm$ after $O_2$ annealing at $800^{\circ}C$. We can decrease RC by lowering temperature of $O_2$ annealing. The isolation resistance of test structure which indicated the surface and buffer leakage current was significantly increased from $2.43{\times}10^7$ to $1.32{\times}10^{13}{\Omega}$ due to $O_2$ annealing. The improvement of isolation resistance can be caused by formation of group-III oxides on the surface. The leakage current of GaN Schottky barrier diode was also suppressed from $2.38{\times}10^{-5}$ to $1.68{\times}10^{-7}$ A/mm at -100 V by $O_2$ annealing. The GaN Schottky barrier diodes achieved the high breakdown voltage of 700, 1400, and 1530 V at the anode-cathode distance of 5, 10, and $20{\mu}m$, respectively. The optimized $O_2$ annealing and $4{\mu}m$-thick C-doped GaN buffer obtained the high breakdown voltage at short drift length. The proposed $O_2$ annealing is suitable for next-generation GaN power switches due to the simple process and the low the leakage current.

• The Korean Journal of Food And Nutrition
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• v.16 no.2
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• pp.111-115
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• 2003

This study was practiced to investigate characteristics and antibiotics susceptibility to 296 isolates of Escherichia coli isolated from 2429 fishery samples sold in Noryangjin Fishery Market from Sep. 2001 to Aug. 2002 It showed 12.2% average E. coli isolation rates for the tested samples. Isolation rates were high in summer, especially July and August, but there was no isolate in winter season. Of the fishery groups, the isolation rate showed in crustacea(15.6%), in mollusca(14.4%), in shellfish(12.0%) and in fish(11.0%). But, differences between the fishery groups was not large. In the case of shellfish, the isolation rate of shucked shellfish (16.3%) was higher than the non-shucked shellfish (6.8%). Following the provinces of origin of the fishery samples, in Gyung-Nam (14.3%) showed the highest isolation rate, whereas Je-Ju (6.9%) showed the lowest isolation rate. Results in 12 kinds of antibiotics susceptibility test, the 169 isolates(57.1%) had antibiotics resistances at least one kind of antibiotics and the 104 isolates (35.1%) had the multiple resistance at least two kinds.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.123-129
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• 2008

To isolate Bacillus cereus presenting at a level of 5 log CFU/g in kochujang, a primary dilution ($10^{-1}$) of kochujang was heated at $85^{\circ}C$ for 5 min. Two isolated strains Voges-Proskauer positive colony (KBC) and a negative colony (KBM) were identified as B. cereus and Bacillus mycoides, respectively, by biochemical test and 16S rDNA sequencing. $D_{100^{\circ}C}$-Values of KBC and KBM strains was 8.37 and 7.08 min, respectively. When spores of KBC strain were inoculated to kochujang at the level of 4-5 log spores/g, the number of spores was no significant difference (p<0.05) for each sample from 1 up to 60 day of aging. When kochujang was inoculated with 4 log spores/g and heated at $85^{\circ}C$ for 15 min, the number of spores was similar to that of unheated kochujang. Therefore, we estimated that B. cereus isolated from kochujang resistant on the heat treatment ($85^{\circ}C$, 15 min) and its heat resistance characteristics could be used to count the number in kochtjang.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.291-301
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• 1989

To investigate the epidemiological trait of intestinal diseases of animals caused by thermophilic Campylobacter spp., isolation of etiological agent was carried out. Isolated Campylobacter spp. were biotyped, serotyped and the susceptibility of the isolates to antimicrobial agents were examined. Th results were as follows. 1. Isolation rates of Campylobacter spp. from 649 fecal materials of 208 cattle, 300 pigs and 141 chickens were 25.5%, 23.7% and 38.3%, respectively. 2. The majority of the 130 isolates of C jejuni was classified as biotype I(50.6%) and biotype II (34.6%). Most of the 46 isolates of C coli were biotype I (71.7%). 3. Isolated C jejuni strains showed 14 different serotype, and serotype 4, 26, 36 were most frequent. Isolated C coli strains showed 5 different serotype and serotype 31 and 21 were relatively common. 4. Isolated Campylobacter spp. were highly susceptible to nalidixic acid, amikacin, gentamicin, colistin and chlorampehnocol.

• Korean Journal of Veterinary Service
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• v.33 no.3
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• pp.241-248
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• 2010

The present study was conducted to investigate isolation and antimicrobial resistance ratio of E. coli, E. faecium and E. faecalis from feces(l50 samples) and carcasses (150 samples) on slaughtered pigs from 6 slaughterhouse of 13 cities in the Gyeongnam during the period from January 2009 to December 2009. Isolation ratio of E. coli from feces and carcasses were 98 (65.3%) and 110(73.3%), respectively, and simultaneously, E. faecalis and E. faecium from feces and carcasses were isolated 21 (14%), 52(34.7%) and 18(12%), 14 (9.3%), respectively. All E. coli isolated from feces and carcasses except cefepime (0%) and ceftiofur (0%) were exhibited 2.4~83.6% of resistance to teteracycline (83.6%), ampicillin (68.2%), streptomycin (60%), chloram-phenicol (53.8%) and cephalothin (2.4%). All E. faecalis isolated from feces and carcasses except penicillin(0%) and vancomycin (0%) were exhibited 2.7~80.8% of resistance to teteracycline (80.8%), quinupristin/dalfopristin (78%), erythromycin (56.1%), streptomycin (43.8%) and bacitracin (2.7%). All E. faecium isolated from feces and carcasses except gentamicin (0%), vancomycin (0%), florfenicol (0%), linezloid (0%) and bacitracin (0%) were exhibited 3.1~53.1% of resistance to rifampin (53.1%), erythromycin and tetracycline (25%), penicillin (15.6%), ciprofloxacin (9.3%), and streptomycin, chloramphenicol, and quinupristin/dalfopristin (3.1%). According to the heard size, resistance ratio of E. coli strains isolated from feces and carcasses in slaughtered pigs-breeding farms over 1,500 heard to tetracycline, ampicillin, streptomycin and chloramphenicol showed higher resistance ratio (1.0~16.8%) than those of farms-breeding under 1,500 heard. From the our results, we suggest that a few of antimicrobials were used in the Gyeongnam than the other cities.

• Korean Journal of Veterinary Service
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• v.34 no.1
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• pp.45-54
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• 2011

This study was conducted to investigate the distribution of Salmonella spp. from pigs and cattle in slaughterhouse, the antimicrobial resistance pattern and the prevalence of resistance genes of isolates. A total of 640 fecal samples from pigs and cattle in slaughterhouse were collected for isolation of Salmonella spp.. Isolation rate was revealed as 15% in pigs and 1.6% in cattle. As result of serotyping, group B (56.6%) were identified as most common in pigs and cattle isolates, in order of group C (24.5%) and group E (15.1%). S. Typhimurium (50.9%) was most common serotype. The major serotypes were in order of S. Rissen and S. London (11.3%) and S. Riggil (7.6%). In antimicrobial test, all isolates were demonstrates susceptibility to nitrofurantoin. But isolates were revealed resistance other antibiotics in order of tetracycline (64.6%), streptomycin (68.3%), ampicillin and amoxicillin (56.3%) and spectinomycin (47.9%). With polymerase chain reaction, antimicrobial resistance gene strA (75.0%) and aadA1 (3.1%) were detected in streptomycin resistance isolates and tetA (94.3%) and tetB (11.3%) gene were detected in tetracycline resistant isolates, but tetG was not detected. Class 1 integron gene was detected in all Salmonella isolates.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.4
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• pp.55-61
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• 2008

One of the most recent base-isolation systems to improve the earthquake resistance of structures is the Friction Pendulum System(FPS). Simple in design but with versatile properties, the FPS has been used in some of the world s largest seismically isolated buildings, bridges and chemical tanks. FPS using PTFE(Polytetrafl-uoroethylene) based material has been developed to provide a simple and effective way for structures to achieve earthquake resistance. PTFE materials are soft, and are apt to become deformed easily after a few working cycles. In this study, magnetic force is used rather than the usual PTFE materials to improve the material shortcomings. A MF-FPS(Magnetic force-Friction Pendulum System) is proposed, and us shown to effectively protect structures against earthquakes. To demonstrate the advantages of this new system, the MF-FPS is compared with FPS as an attempt to prove its performance. A six-degree-of-freedom model is considered as a numerical example. The ground acceleration data of El Centro, Mexico and Gebze earthquakes are used as seismic excitations. The results showed that MF-FPS improved performance compared with FPS.