• Animal Bioscience
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• 제35권1호
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• pp.138-146
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• 2022

Objective: The objective of the current study was to investigate the influences of conventional (CO) and deep litter (DE) systems on antimicrobial resistance in fecal Escherichia coli (E. coli). Methods: A cross-sectional study was carried out to detect antimicrobial resistance to E. coli in swine fecal samples in CO and DE systems located in western and northeastern Thailand. Individual rectal swab samples were taken only from healthy pigs. A total of 215 individual and healthy pigs were randomly selected for isolation and antimicrobial susceptibility test of E. coli by the disc diffusion method. The test panel included amoxicillin (AMX), colistin, doxycycline (DOX), enrofloxacin, gentamicin (GEN), kanamycin, neomycin (NEO), and trimethoprim-sulfamethoxazole (SXT). Results: There were significant (p<0.05) lower resistance levels for GEN, NEO, and SXT in the DE farms compared to those in the CO farms. There was a lower number of antimicrobial resistance agents (p<0.001) in the DE farms compared to those in the CO farms. This result was consistent with those in western (p<0.01) and northeastern (p<0.01) Thailand. Overall, antibiograms of AMX-SXT and AMX-DOX-SXT were found in the CO (19.09% and 20.91%, respectively) and the DE (16.19% and 24.76%, respectively) farms. No antimicrobial resistance (5.71%) was found and AMX (13.33%) resistant pigs in the DE farms, whereas the pattern of AMX-GEN-SXT (6.36%) and AMX-DOX-GEN-SXT (11.82%) resistant pigs was found in the CO farms. Conclusion: The DE system for pig farming was superior to conventional pig farming by lowering the resistance level of fecal E. coli to GEN, NEO, and SXT, with decreasing the number of antimicrobial resistance agents and inducing a small proportion of pigs to be free from antimicrobial resistance.

• 동력기계공학회지
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• 제20권5호
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• pp.20-28
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• 2016

This study has developed an organic/inorganic hybrid solution by addition of $SiO_2$ polysilicate and Melamine to the urethane. The three types of cold rolled steel were evaluated a corrosion resistance properties by using these solutions. The urethane solution(U) and the urethane solution with $SiO_2$ polysilicate($US_7$) were generate a lot of corrosion. The urethane solution with $SiO_2$ polysilicate and melamine($US_7M_3$) was excellent in corrosion resistance, regardless of the steel type. In addition, corrosion resistance has been shown to depend on the tensile strength. The appearance of coating by U and $US_7$ solution is bumpy surface, and were a lot of fine defects. $US_7M_3$ solution is made a sophisticated molecular cross-linking structure inside the coating, it was a slick surface. Other characteristics are exhibited the excellent property for all solutions.

• Plant Resources
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• 제7권2호
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• pp.147-154
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• 2004

Antifreeze proteins (AFPs) accumulate in the leaves of barley during cold acclimation, where they may inhibit ice recrystallization and produce freezing resistance of the plant. Four parental diallel crosses of the barley varieties were used to determine the heritability of AFPs and the relationship between the accumulation level of AFPs and freezing resistance. The concentration of apoplastic proteins in the cold-acclimated leaves was increased in the mean by four-fold over as compared with that of nonacclimated. The diallel cross analyses revealed that the gene of Sacheon 6 was dominant and those of Reno and Dongbori 1 were recessive. The AFPs had high narrow-sense heritabilities. The general combining ability effects of Reno and Dongbori 1 were much higher than the other parents. The bands of 32-kD for GLP, 35-& 28-kD for CLP and 25-, 22- & 16-kD for TLP were observed in the apoplastic extracts from cold-acclimated plants, but there were no clear differences between the parents and Fl hybrids. The concentrations of AFPs were significantly correlated with the degree of freezing resistance, indicating that the concentration of AFPs in the plant is the very important factor for freezing resistance.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.148-149
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• 2008

As infrared light is radiated, the CMOS Readout IC (ROIC) for the microbolometer type infrared sensor detects voltage or current when the resistance value in the bolometer sensor varies. One of the serious problems in designing the ROIC is that resistances in the bolometer and reference resistor have process variation. This means that each pixel does not have the same resistance, causing serious fixed pattern noise problems in sensor operations. In this paper, Reference resistor compensation technique was proposed. This technique is to compensate the reference resistance considering the process variation, and it has the same reference resistance value as a bolometer cell resistance by using a comparator and a cross coupled latch.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.57-60
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• 2004

Electrical arc is the final stage of insulation breakdown and has high current density which cause heat and light in insulator. Insulator under electrical arc lost its insulating strength and eternal damages. Conventional criterion of electrical arc resistance in Standards have depended on the change of sound pressure and light color after damages on insulator by electrical arc. The recognition of these changes is done by human himself which was very subjective and resulted in some error to judge whether insulator has damages or not. This paper has shown that antenna method is the appropriate measure to judge electrical arc resistance for insulator. Antenna measures the electromagnetic waves radiated from tungsten electrodes with 6mm gap regulated by KSC2130. Applied voltage cross two tungsten electrodes have two different methods such as 1/8 10 and continuous 10mA. Signal amplitudes obtained by antenna has diminished after the damage of insulator, which will provide objective and good way to judge the electrical arc resistance.

• 한국해양공학회지
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• 제27권6호
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• pp.1-6
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• 2013

A 25ft class fishing leisure boat is developed, and the resistance performances are investigated by a model test in a high-speed circulating water channel. The design speed of the developed ship is 25 knots using a 150 ps outboard engine. A catamanan type hull form using a planing section is adopted considering the Froude number and large deck area. The effect of a center body attached on the bottom of the cross deck is studied under various conditions. Wave patterns are observed to make clear the relationship between the resistance performance and the wave characteristics. The results show that the shape of the center body and the position of the chine line can have a strong effect on the resistance performance in a certain velocity range.

• 한국주조공학회지
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• 제40권6호
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• pp.135-145
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• 2020

Aluminum cast iron has excellent oxidation resistance, sulfurization resistance, and corrosion resistance. However, the ductility at room temperature is insufficient, and at temperatures above 600?, the strength drops sharply and practicality is limited. In the case of heat-resistant cast iron, high-temperature materials containing Cr and Ni account for 30 to 50% or more. However, these high-temperature materials are expensive. Aluminum heat-resistant cast iron is considered as a substitute for expensive heat-resistant materials. Oxidation due to the aging temperature and holding time conditions increases more in 0 wt.% Al-cast iron than in 2 and 4 wt.% Al-cast iron according to oxidized weight and gravimetric oxide layer thickness measurements. As a result of observing the cross-section of the oxide layer, it was found to contain 0 wt.% of Al-cast iron silicon oxide-containing SiO₂ or Fe₂SiO₄ oxide film. In cast iron containing aluminum, the thickness of the internal oxide layer due to aluminum increases as the aging temperature and retention time increase, and the amount of the iron oxide layer generated on the surface decreases.

• 대한금속재료학회지
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• 제46권11호
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• pp.725-729
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• 2008

Deposition characteristics of electroless plated Ni-W-P films were investigated for various complexing agents. Used complexing agents are sodium citrate, sodium gluconate and sodium malonate. In this study, the existing mixed potential theory could explain the overall mechanism of Ni-W-P electroless plating for all complexing agents. The deposition rate could be also expected by the theory. The deposited Ni-W-P films were evaluated in term of surface hardness and corrosion resistance. Microhardness of the deposit increased about 1,000 Hv after heat treatment for one hour at $400^{\circ}C$, because it was above the crystallization temperature of $Ni_3P$. The deposited Ni-W-P films can exhibit excellent corrosion resistance in using sodium malonate as a complexing agent, the other hand the using sodium gluconate was the worst corrosion resistance. The worst corrosion resistance was due to a large number of nano-sized pin-holes or small pores. The plating current at the mixed potential increases when the using sodium malonate as a complexing agent, it was explained by the cross section.

• 농약과학회지
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• 제19권3호
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• pp.329-334
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• 2015

병든 토마토, 딸기, 오이 등의 열매에서 분리한 86개의 Botrytis cinerea의 균주를 가지고 한천희석법을 통하여 mepanipyrim의 균사생장 억제효과를 조사하였으며, $EC_{50}$값을 계산하여 저항성 모니터링을 실시하였다. 병원균의 저항성 모니터링을 PDA 배지에서 실시할 경우 mepanipyrim의 균사생장 억제효과를 정확하게 검정할 수 없었으나, FGA 배지를 사용하였을 때에는 감수성과 저항성 반응을 뚜렷하게 구분할 수 있었다. 실험에 사용한 B. cinerea의 86개 균주를 $1.0{\mu}g\;mL^{-1}$의 $EC_{50}$값을 가지고 감수성과 저항성을 구분하였으며, 전체 균주 중에서 20개인 23.3%가 저항성균으로 분류되었다. 지역에 따라서 저항성균의 분리비에는 차이가 있었는데, 경기, 경남/부산, 그리고 충남에서 각각 분리한 균주 중에서 저항성균의 비율은 28.6, 33.3, 12.8%로, 경남/부산 지역에서 가장 높았다. Mepanipyrim에 대한 저항성균은 pyrimethanil에 대해서도 교차저항성을 보였으며, 오이 자엽에 대한 병원성을 감수성 균주와 비교해 보아도 전혀 떨어지지 않았다. 따라서 포장에서 anilinopyrimidine계 살균제를 효과적으로 사용하기 위해서 적극적인 관리가 필요한 상태이다.

• 대한임상검사과학회지
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• 제54권2호
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• pp.125-132
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• 2022

다제내성결핵과 광범위내성결핵은 결핵 치료의 문제가 되고 있으며 발생빈도 역시 증가하고 있다. 본 연구는 2010년 1월부터 2019년 12월까지 녹십자의료재단 의뢰된 환자를 대상으로 Löwenstein-Jensen 고체배지와 pyrazinamide for pyrazinamidase를 이용하여 약물감수성시험(DST)을 시행하여 내성으로 전환되는 항결핵제 패턴과 평균 추적 기간을 분석하였다. 항결핵제 중 1개 이상의 항결핵제 내성을 보인 증례들에서 초기 의뢰 시 INH 항결핵제에 내성인 경우가 55명(33.1%)으로 가장 높은 비율로 나타났으며, 내성으로 전환된 항결핵제는 EMB 17명(26.6%), RFP 14명(21.9%), QUI 14명(21.9%), PZA 12명(10.9%) 순으로 조사되었다. 10개의 항결핵제에 모두 감수성인 증례들에서는 INH 항결핵제에 대한 내성 전환은 43명(7.2%)으로 가장 빈도가 높았으며, 평균 추적 기간은435.6일로 조사되었으며, 내성으로 전환되는 항결핵제의 내성전환율은 INH 43명(7.2%), RFP 23명(3.9%), SM 11명(1.9%), QUI 4명(0.7%), AMK 3명(0.5%), EMB 3명(0.5%)이었다. 이에 본 연구는 항결핵제에 대한 감수성에서 내성으로의 전환은 특히 다제내성결핵과 광범위 내성결핵의 전환되는 환자에게 매우 중요한 자료가 될 것으로 보이며, 결핵 치료에서 환자 치료에 도움이 될 것으로 사료된다.