• Korean Journal of Veterinary Research
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• v.39 no.4
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• pp.765-771
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• 1999

Unlike most Escherichia coli strains, E coli O157 : H7 didn't ferment sorbitol within 24h of incubation and showed a negative reaction for $\beta$-glucuronidase. We developed a new medium for the rapid isolation of E coli O157 : H7 using sorbitol MacConkey agar with cefixime, potassium tellurite and 4-methylumbelliferyl-${\beta}$-D-glucuronide (MUG) as a primary plating medium. The addition of $20{\mu}g/ml$ of vancomycin in enrichment broth for E coli O157 : H7 inhibited lots of Gram positive bacteria. Three strains (10.3%) of 29 non-O157 E coli strains and 3 strains (8.3%) of 36 Salmonella spp were inhibited at the $0.05{\mu}g/ml$ of cefixime and 23 strains (79.3%) of 29 non-O157 E coli strains and 12 strains (33.3%) of 36 Salmonella spp were inhibited at the $2.0{\mu}g/ml$ of potassium tellurite. But none of the E coli O157 : H7 was affected at these concentration. The addition of MUG at $100{\mu}g/ml$ level to sorbitol MacConkey agar with cefixime and potassium tellurite (CTM-SMAC) aided in the rapid isolation of E coli O157 : H7 from samples by checking sorbitol-negative and $\beta$-glucuronidase negative phenotypes simultaneously. In conclusion, inoculation of a positive in the O157 screening test from enrichment broth on CTM-SMAC appeared to be a rapid, cost-effective and sensitive method for the isolation of E coli O157 : H7.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.241-244
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• 2002

Deburring is conducted using MAF(magnetic abrasive finishing) method. Magnetic inductor is designed and manufactured to generate proper magnetic induction far deburring the burr formed in drilling SM45C. Rotational speed, table feed rate, grain size of powder and working gap are changed to investigate the effect on deburring.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1904-1917
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• 2016

The moving average filter (MAF) is widely utilized to improve the disturbance rejection capability of phase-locked loops (PLLs). This is of vital significance for the grid-integration and stable operation of power electronic converters to electric power systems. However, the open-loop bandwidth is drastically reduced after incorporating a MAF into the PLL structure, which makes the dynamic response sluggish. To overcome this shortcoming, some new techniques have recently been proposed to improve the transient response of MAF-based PLLs. In this paper, a comprehensive performance comparison of advanced MAF-based PLL algorithms is presented. This comparison includes HPLL, MPLC-PLL, QT1-PLL, and DMAF-PLL. Various disturbances, such as grid voltage sag, voltage flicker, harmonics distortion, phase-angle and frequency jumps, DC offsets and noise, are considered to experimentally test the dynamic performances of these PLL algorithms. Finally, an improved positive sequence extraction method for a HPLL under the frequency jumps scenario is presented to compensate for the steady-state error caused by non-frequency adaptive DSC, and a satisfactory performance has been achieved.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2582-2589
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• 2011

This Paper proposed the prediction method of fuel consumption from vehicle diagnosis informations through OBD-II Interface. We assumed mass air flow (MAF), shor-term fuel trim (STFT), and long-term fuel trim (LTFT) had a relationship with fuel consumption. We got the output as fuel-consumption from MAF, STFT, and LTFT as input variables. We had modelling as combustion reaction equation with OBD-II data and fuel consumption data supported by automotive company in real. In order to verify the effectiveness of proposed method, 5 km real road-test was performed. The results showed that the proposed method can estimate precisely the fuel consumption from vehicle data.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.77-86
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• 2003

Pullorum disease due to Salmonella enterica subspecies enterica bioserovar Pullorum (S. pullorum) is reported to be an endemic disease in domestic poultry flocks. The pulsed-field gel electrophoresis (PFGE) subtyping method was used to assess the extent of genetic diversity and clonality of most of salmonella serotypes and other diverse bacterial species from animals and environmental samples in worldwide. Nowadays, PFGE has already been evaluated as a gold standards for molecular subtyping of salmonella serotypes compared with other molecular analysis methods. PFGE of XbaI digested chromosomal DNA from 23 strains of S. pullorum gave 5 distinctive pulsotypes (from SXPI to SXPV) with 5% confidence range of Dice coefficients, indicating that PFGE is very discriminative and that multiple clones of S. pullorum have been existed and diffused all of domestic poultry flocks industries since 1995. Two dominant pulsogroups (SXA & SXB) appeared as a major clones in this country, because they had consistently been recovered from diverse sources including both chicken organs and raw feed materials between 1995 and 1998. In addition, the matching percentage of PFGE profiles (PFP) among strains from both chickens and feed ingredients provides indirect evidence of the possible transmission of pullorum disease from contaminated raw feed ingredients for chicken production. In calculating of discrimination index (DI) for PFGE method by Simpson's index, DI was appeared as 0.917. Therefore, this index suggested that the present PFGE would seem to be a desirable and confident molecular typing method for S. pullorum strains. To our knowledge for pullorum disease, this is the first study to compare S. pullorum strains from chicken organs and feed samples using the PFGE.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1877-1880
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• 2003

We were interest in Deburring using MAF(magnetic abrasive finishing) method. So Magnetic inductor was designed and manufactured to generate proper magnetic induction fer deburring the burr formed in drilling SM45C. We experienced according to the Rotational speed, table feed rate, grain size of powder and working gap are changed to investigate the effect on deburring. At this time we experienced in abrasive effect mainly.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.188-198
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• 2015

The validity of applying the Modified Airy Function (MAF) method to the problems of graded-index optical waveguides and graded potential barrier analysis was critically examined. In the former case, the method yielded very accurate results from the derived eigenvalue equations. In the latter case, however, the same method produced results that deviated significantly from exact numerical results for barriers with a smooth peak. The causes of the discrepancies were investigated in detail.

• Restorative Dentistry and Endodontics
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• v.27 no.1
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• pp.66-76
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• 2002

The purpose of this study is to evaluate the effectiveness of customized master cone on apical sealing in various apical size of prepared root canals, that is MAF(Master Apical File) and to know at which apical size the apical leakage is to be significantly reduced using customized master cone. 120 extracted single rooted premolars were divided into four groups according to their apical size(MAF), #30, 40, 50 and 60. And then, each group was subdivided into three in accordance with three obturation methods, lateral condensation with standardized master cone, lateral condensation with chloroform-dipped customized master cone, and continuous wave of obturation technique. Resorcinol-formaldehyde resin was used for the microleakage test of this study. Teeth were sectioned horizontally at 1.5mm(Level 1), 2.5mm(Level 2), and 3.5mm(Level 3) from the anatomical root apex using low speed microtome. All sections were examined under $\times$40 magnification with a stereomicroscope, photographed, and then scanned. With the scanned images, resin-infiltrated area presenting the microleakage was calculated using SigmaScan/Image, and the ratio of leakage to the total root canal area of each group was analyzed statistically(one way ANOVA). The results were as follows ; 1. In groups of MAF #30, there was no significant difference of mean leakage ratio among three obturation methods at all three levels. 2. In groups of MAF #40, the group using lateral condensation with customized master cone had the low-est mean leakage ratio at all three levels, but there was no significant difference among three obturation techniques. 3. In groups of MAF #50, the mean leakage ratio of the group using lateral condensation with standard master cone was the highest among those of three obturation techniques at level 1, and this difference was statistically significant(p<0.05). 4 In groups of MAF #60, the groups using lateral condensation with standard master cone had also the highest mean leakage ratio at all levels, but there was no significant difference at level 1 and 2. At level 3, the leakage of the group using lateral condensation with standard master cone was significantly higher than that of the group using continuous wave of obturation(p<0.05). The results of this study suggested that the obturation method using customized master cone or the continuous wave of obturation is more effective for apical sealing than that using standardized master cone when MAF is larger than ＃50.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.745-750
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• 1998

A sensitive and rapid enzyme immunoassay(EIA) to detect Escherichia coli O157 in ground beef was developed by using a sandwich type assay with polyclonal antibodies to E coli O157. E coli O157 in ground beef could be detected within 15hr, including incubation for 12hr in enrichment broth and 3hr in immunoassay. The EIA could detect $1.3{\times}10^5$ cells of E coli O157/g of ground beef without enrichment. The lowest limit of detection was 0.23 E coli O157 per g of meat after enrichment. Confirmation was required in the positive specimens in the EIA by culture method even though the negative specimens were not. These results suggested that the immunoassay could be a very efficient method for the screening E coli O157 in meat.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.771-776
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• 1998

Synthetic oligonucleotide primers of 20 and 21 bases, respectively, were used in the polymerase chain reaction (PCR) to amplify a sequence of the mrp gene, which encodes the muramidase released protein of Streptococcus suis. Amplification was not recorded when 5 other streptococcal species were tested or when 9 different nonstreptococcal species were tested. A DNA fragment of 517bp was amplified from the genomic DNA of S suis. The lower detection limit was 100pg of the genomic DNA. The primers recognized 34 serotypes of S suis reference strains and 9 isolates from pneumonic lung, brain, nasal discharge, tonsil. This results suggest that the amplification of the mrp gene by PCR method is potential for the identification of S suis isolates.