• 대한전자공학회논문지SD
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• 제41권11호
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• pp.1-6
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• 2004

RFIC를 위한 Nanoscale MOSFET에서의 유효 게이트 저항을 직접 추출법으로 추출하여 다양한 게이트 길이에 대해 분석하였다. 추출된 유효 게이트 저항은 비교적 정확하면서 간소화된 모델을 통한 측정결과와 비교하여 10GHz 대역까지 잘 일치함을 확인하였다. 같은 공정기술로 제작된 소자들 중에서 reverse short channel 효과가 생기지 않는 긴 채널 MOSFET 소자의 경우에 일반적인 유효 게이트 저항에서와는 다른 인가전압 및 주파수 종속성을 가짐을 확인하였다. 특히, 문턱전압을 전후하여 주파수에 따라 상이한 결과를 나타내고 있으며, 게이트 인가전압이 문턱전압에 가까울 때 비이상적으로 큰 유효 게이트 저항값을 나타내었다. 이러한 특성은 직접추출법을 사용하는 RF MOSFET 모델링에 있어서 참고해야 할 중요한 특성이 될 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1246-1247
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• 2008

With recent advanced in portable electric devices, wireless sensor, MEMS and bio-Mechanics device, the new typed power supply, not conventional battery but self-powered energy source is needed. Particularly, the system that harvests from their environments are interests for use in self powered devices. For very low powered devices, environmental energy may be enough to use power source. Therefore, in other to made piezoelectric energy harvesting device, PMN-PZT thick film was formed by the screen printing method on the Ag/Pd coated alumina substrate. The layer was 8 layers and slurry where a-terpineol, ethycellulose, ferro B-75001 as Vehicle, PMN-PZT powder used are fabricated by ball mill. The output power quality was be also investigated by changing the load resistance, weight and frequency. The made piezoelectric energy harvesting device was resulted from the conditions of 33$k{\Omega}$, 0.25g, 197Hz respectively. The thick film was prepared at the condition of 2.75Vrms, and its power was 230${\mu} W$ and its thickness was 56${mu}m$. The piezoelectric energy harvesting device output voltage was increased, when the load weight, load resistance was increasing and resonance frequency was diminishing. The other side, resonance frequency was diminished, when the weight was increasing. And output power was continuously it changed by load resistance, output voltage, weight and resonance frequency.

• 한국안전학회지
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• 제9권4호
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• pp.42-48
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• 1994

A rotor flux error-based approach for correcting the rotor time constant estimation used in the slip frequency calculator of indirect field oriented controller is presented in this paper. The controller was derived from the d-q induction machine model. Slip frequency gain is dependent on the machine parameter errors. And parameter errors result in rotor flux error. Thus, estimated rotor flux is compared to commanded rotor flux. The error between them is used for the estimation of rotor time constant. Simulation results which demonstrate the performance of this approach are presented.

• Transactions on Electrical and Electronic Materials
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• 제6권3호
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• pp.97-100
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• 2005

Dynamic response of organic light-emitting diodes were analyzed in $ITO/Alq_3$(100 nm)/Al device structure with a variation of voltage an frequency. At low frequency region, complex impedance is mostly governed by resistive component, and at high frequency region by capacitive component. Also, we have evaluated resistance, capacitance and permittivity of devices.

• Clinical and Experimental Reproductive Medicine
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• 제40권2호
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• pp.76-82
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• 2013

Objective: To compare the blood glucose levels, insulin concentrations, and insulin resistance during the two phases of the menstrual cycle between healthy women and patients with premenstrual syndrome (PMS). Methods: From January of 2011 to the August of 2012, a descriptive cross-sectional study was performed among students in the School of Medicine of Jahrom University of Medical Sciences. We included 30 students with the most severe symptoms of PMS and 30 age frequency-matched healthy controls. We analyzed the serum concentrations of glucose, insulin, and insulin resistance by using the glucose oxidase method, radioimmunometric assay, and homeostasis model assessment of insulin resistance equation, respectively. Results: No significant differences between the demographic data of the control and PMS groups were observed. The mean concentrations of glucose of the two study groups were significantly different during the follicular and luteal phases (p=0.011 vs. p<0.0001, respectively). The amounts of homeostasis model assessment of insulin resistance of the two study groups were significantly different in the luteal phase (p=0.0005). Conclusion: The level of blood glucose and insulin resistance was lower during the two phases of the menstrual cycle of the PMS group than that of the controls.

• Journal of Pharmaceutical Investigation
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• 제24권4호
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• pp.281-287
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• 1994

The effects of oleic acid, propylene glycol and 5% (w/w) oleic acid in propylene glycol on the electrical properties of hairless mouse skin were studied and the results were compared. The complex electrical impedance was measured as a function of frequency, and resistance and capacitance were determined from the Nyquist plot. Immediately after the treatment with oleic acid, resistance was 145% of the pretreatment value. However it decreased with time and, after 20 hours, it was about 25% of its pretreatment value. Capacitance increased; immediately after the treatment, it was about 125% of pretreatment value and it seemed to increase slowly with time. When the skin was treated with propylene glycol, resistance decreased about 5O% and capacitance increased about 65%. Similar results were observed when the skin was treated with 5% (w/w) oleic acid in propylene glycol, except that the magnitude of resistance drop was much larger. Oleic acid acted synergistically with propylene glycol. Together with the flux data in the literature, the results obtained in this work indicate that electrical resistance is closely related to the permeability of drug molecules through the skin. The results are discussed in terms of the mechanism of action of these penetration enhancers. Overall, this work provided further mechanistic insight into the role of SC lipids in skin resistance and capacitance.

• 약학회지
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• 제50권3호
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• pp.199-203
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• 2006

A new type of macrolides, lincosamides and streptogramin B antibiotics (MLS) resistance, showing the characteristic phenotype growing within the inhibition zone area around the clindamycin disk, was identified among clinically isolated Staphylococcus aureus. We named the phenotype as MLS resistance with foggy-D shape (fMLS). The average frequency of MLS isolates was 9%. All of fMLS isolates have only erm(A) for the resistance determinant. The growth pattern of the challenged MLS isolate looks intermediate phase between the patterns of inducible MLS resistance and constitutive MLS resistance.

• Weed & Turfgrass Science
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• 제7권2호
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• pp.166-169
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• 2018

경남지역 제초제 저항성 피의 발생현황과 저항성 정도를 알아보기 위하여 벼 재배 논에서 100개체의 피 종자를 수집하여 ACCase 저해제인 cyhalofop-butyl에 대한 약량반응 실험을 수행한 결과, 수집한 피의 7%가 저항성으로 조사되었다. 선발된 감수성 5개체의 $GR_{50}$값은 평균 $147g\;a.i.\;ha^{-1}$로 나타났고, 함양 지역의 저항성 개체의 $GR_{50}$값은 $738g\;a.i.\;ha^{-1}$ 로 R/S (ratio of resistance to sensitivity)값은 5.01배로 나타났다. 현재 경남지역에서의 저항성 피의 발생 수준은 낮은 것으로 나타났지만, 저항성 피의 확산을 지연시키거나 막기 위해서는 주기적인 저항성 피의 모니터링과 체계적인 저항성 잡초 관리방안을 마련하여 수행할 필요가 있다.

• Corrosion Science and Technology
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• 제11권4호
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• pp.135-140
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• 2012

The linear polarization resistance method is one of the widely used techniques for the corrosion rate monitoring in the water circulating systems of plants. The measurement is simple and rapid, so that a continuous on-line monitoring is possible without any shutdown of plants. A 2-electrode polarization corrosion rate measurement system was installed in a laboratory using a data acquisition board and PC. The signal processing parameters were optimized for the accurate corrosion rate measurement, and the polarization resistance was compensated with the solution resistance measured by the high frequency sine wave signal of an output channel. The precision of corrosion rate data was greatly improved by removing the initial noise signals on measuring the polarization resistance.

• The Plant Pathology Journal
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• 제21권3호
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• pp.237-243
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• 2005

Resistance inductions on the leaves of cucumber plant by an arbuscular mycorrhiza Glomus intraradices were investigated. In addition, the infection structures were observed at the penetration sites on the leaves of plant inoculated with Colletotrichum orbiculare using a fluorescence microscope. The severity of anthracnose disease caused by Colletotrichum orbiculare was significantly decreased on the leaves of cucumber plant colonized with G intraradices compared with those of non-treated control plants. As a positive control, pre-treatment with DL-3-aminobutyric acid (BABA) caused a remarkable reduction of the disease severity on the pathogen-inoculated leaves. There were no significant differences in the frequency of either germination or appressorium formation of the plant pathogen between mycorrhiza colonized and non-treated plants. It was also the same on the BABA pre-treated plants. However, the frequency of callose formation was significantly high on the leaves of G intraradices colonized plants compared to those of non-treated control plants at 5 days after challenge inoculation. On the leaves of BABA treated plants callose formation was not significantly high than those of non-treated, although the disease severity was more strongly suppressed. It was suggested that the resistance induced by colonization with G. intraradices might be related to the enhancement of callose formation at the penetrate sites on the leaves invaded by the pathogen, whereas resistance by BABA did not.