• Title/Summary/Keyword: line resistance

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Treatment of Isoniazid-Resistant Pulmonary Tuberculosis

  • Jhun, Byung Woo;Koh, Won-Jung
    • Tuberculosis and Respiratory Diseases
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    • v.83 no.1
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    • pp.20-30
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    • 2020
  • Tuberculosis (TB) remains a threat to public health and is the leading cause of death globally. Isoniazid (INH) is an important first-line agent for the treatment of TB considering its early bactericidal activity. Resistance to INH is now the most common type of resistance. Resistance to INH reduces the probability of treatment success and increases the risk of acquiring resistance to other first-line drugs such as rifampicin (RIF), thereby increasing the risk of multidrug-resistant-TB. Studies in the 1970s and 1980s showed high success rates for INH-resistant TB cases receiving regimens comprised of first-line drugs. However, recent data have indicated that INH-resistant TB patients treated with only firs-tline drugs have poor outcomes. Fortunately, based on recent systematic meta-analyses, the World Health Organization published consolidated guidelines on drug-resistant TB in 2019. Their key recommendations are treatment with RIF-ethambutol (EMB)-pyrazinamide (PZA)-levofloxacin (LFX) for 6 months and no addition of injectable agents to the treatment regimen. The guidelines also emphasize the importance of excluding resistance to RIF before starting RIF-EMB-PZA-LFX regimen. Additionally, when the diagnosis of INH-resistant TB is confirmed long after starting the first-line TB treatment, the clinician must decide whether to start a 6-month course of RIF-EMB-PZA-LFX based on the patient's condition. However, these recommendations are based on observational studies, not randomized controlled trials, and are thus conditional and based on low certainty of the effect estimates. Therefore, further work is needed to optimize the treatment of INH-resistant TB.

A STUDY ON THE EFFECTS OF CAVITY FORMS ON FRACTURE OF AMALGAM RESTORATION IN DECIDUOUS MOALRS (유구치 와동형성이 아말감 파절에 미치는 영향에 관한 연구)

  • Ha, Dae-Song;Kim, Chong-Kwan;Lee, Jong-Gap
    • Journal of the korean academy of Pediatric Dentistry
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    • v.11 no.1
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    • pp.159-167
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    • 1984
  • In this experiments, the fracture loads were measured and analysed by using of Instron universal testing machine (Model 1132). With 80 upper and lower deciduous molars that were free of dental caries. Isthmus of teeth were prepared to 1/3 and 1/4 of intercuspal width, and internal line angles with round and sharp shape, and then amalgam restoration were performed. The results of this study were as follows; 1. Resistance to fracture loads were greater with isthmus of 1/3 intercuspal width than of 1/4 intercuspal width, especially, statistically significant difference on upper and lower second deciduous molars. 2. Resistance to fracture loads were greater with rounded internal line angle than sharp internal line angle. The above results were as follows, the fracture loads had greater resistance on isthmus of 1/3 intercuspal width, and rounded internal line angle, but normal physiological occlusal forces could permit isthmus of 1/4 intercuspal width and rounded internal line angle.

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Operating properties of resistive type superconducting fault current limiters with a single line-to-ground fault (1선지락사고에 대한 초전도한류기의 동작특성)

  • Park, Hyo-Sang;Park, Chang-Joo;Lee, Sang-il;Chung, Soo-Bok;Oh, Geum-Kon;Chung, Hun-Sang
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2003.11a
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    • pp.279-281
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    • 2003
  • We analysed the operating properties of resistive type superconducting fault current limiters (SFCLs) based on YBCO thin films with a single line-to-ground fault. When a single line-to-ground fault occurred, the short circuit current of a fault phase increased up to about 6 times of transport currents immediately after the fault instant and was effectively limited to the designed current level within 2 ms by the resistance development of the SFCL. The fault currents of the sound phases almost did not change because of their direct grounding system. The unsymmetrical rates of a fault phase were distributed from 6.4 to 1.4. It was found that the unsymmetrical rates of currents were noticeably improved within one cycle after the fault instant. We calculated the zero phase currents for a single line-to-ground fault using the symmetrical component analysis. The positive sequence resistance was reduced remarkably right after the fault but eventually approached the balanced positive resistance component prior to the system fault. This means that the system reaches almost the three-phase symmetrical state in about 60 ㎳ after the fault. The ground currents were almost 3 times of the zero phase mts since most of the fault currents flowed through the grounding line.

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Analysis of Effective Soil Thermal Conductivities and Borehole Thermal Resistances with a Line Source Method (선형열원법에 의한 지중유효열전도도와 보어홀 전열저항 해석)

  • Lee, Se-Kyoun;Woo, Joung-Son;Ro, Jeong-Geun
    • Journal of the Korean Solar Energy Society
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    • v.30 no.4
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    • pp.71-78
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    • 2010
  • Investigation of the effective soil thermal conductivity(k) is the first step in designing the ground loop heat exchanger(borehole) of a geothermal heat pump system. The line source method is required by New and Renewable Energy Center of Korea Energy Management Corporation in analyzing data obtained from thermal response tests. Another important factor in designing the ground loop heat exchanger is the borehole thermal resistance($R_b$). There are two methods to evaluate $R_b$ : one is to use a line source method, and the other is to use a shape factor of the borehole. In this study, we demonstrated that the line source method produces better results than the shape factor method in evaluating $R_b$. This is because the borehole thermal resistance evaluated with the line source method characteristically reduces the temperature differences between an actual and a theoretical thermal behaviors of the borehole. Evaluation of $R_b$ requires soil volumetric heat capacity. However, the effect of the soil volumetric heat capacity on the borehole thermal resistance is very small. Therefore, it is possible to use a generally accepted average value of soil volumetric heat capacity($=2MJ/m^3{\cdot}K$) in the analysis. In this work, it is also shown that an acceptable range of the initial ignoring time should be in the range of 8~16hrs. Thus, a mean value of 12 hrs is recommended.

An Experimental Study on the Effect of Sensor Line Number on the Reactivity Characteristic of Corrosion Sensor Reactive with Chloride Ion to Immigrate into Concrete (콘크리트내로 침투하는 염소이온 반응형 부식센서의 응답특성에 미치는 센서 세선 수의 영향에 관한 실험적 연구)

  • Lee, Hyun-Seok;Lee, Han-Seung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.3
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    • pp.143-152
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    • 2014
  • In this study, the sensor response and sensitivity is experimented and analyzed quantitatively by the line numbers of chlorine ion reaction type corrosion sensor that is developed. The sensor response of the developed corrosion sensor is verified with properties of chlorine ion. The multilineal sensor is shown a large resistance change more than the single line sensor by damage of the sensor. And, the resistance change of sensor is as large as high concentration of NaCl aqueous solution, the sensitivity of multilineal sensor is higher than single line sensor's, and the depth of sensor's location is as large as the increasing of resistance change time (cycle). These results suggest that, the developed corrosion sensor could sense corrosion reaction, sensor sensitivity and change of resistance for chloride ion. Especially, It was judged that 7 line sensor was the most superior for monitoring chloride ion immigration into concrete.

A basic study on the improvement of the continuous type fishing system for largehead hairtail hand line in coastal area of Jeju island, Korea (제주도 연안 연속식 갈치채낚기 조획시스템의 개량에 관한 기초적 연구)

  • Kim, Byung-Yeob;Lee, Chang-Heon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.45 no.1
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    • pp.14-21
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    • 2009
  • This experimental study was carried out to obtain the base data for saving the man power in the fishing operation of largehead hairtail hand line by using the continuous type hand line system with a rotary device which could make a main line move automatically. In order to solve the twists and entangling on the main line happened during operating test, the resistance board was suspended at the end of the main line at sea. As the result, there were no problems of tangling and so on due to up and down moving of a main line. According to the control of a fixed angle of guide roller, it was possible to prevent the main line to be separated from a side roller and a guide roller. In addition, PVC tube between a guide roller and a side roller enabled a main line to be moved smoothly without any entanglement.

Trust Analysis of Ground Resistance Measurements by the Substitute Auxiliary Electrode (대체 보조전극을 이용한 접지저항 측정 신뢰성 분석)

  • Lee, Sang-Ick;Yoo, Jae-Geun;Jeon, Jeong-Chay;Jeon, Hyun-Jae
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.56 no.2
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    • pp.109-114
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    • 2007
  • This paper summarize about the auxiliary electrode measured a ground resistance. The method to measure a ground resistance is the fall-of-potential method to using an auxiliary electrode. And an auxiliary electrode must be set up on the ground. Today it is so difficult to set up the auxiliary electrode on the ground because of many concrete building and many paved roads. So this paper is regarding a trust analysis of the ground resistance measurement by the substitute auxiliary electrode. It substituted a iron structure around the building, a neutral line multiplex ground to earth, a wire net for auxiliary electrode. This information is confirmed bv compared with the measurement value.

Characteristics of AlW thin film for TFT-FCD bus line

  • Kim, Dong-Sik;Yi, Chong-Ho;Chung, Kwan-Soo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.58-58
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    • 2000
  • Recently low resistance of bus line is required for large screen size RFT-CLD panels. As a result, lower resistance Al-alloy is currently reviewed extensively. The resistivity is required smaller than 10$\mu$$\Omega$cm and high resistance of chemical attack is required. In this paper, Al-W thin film were deposited on glass substrates by D.C magnetron sputtering system under various condition for high chemical resistance. Its properties were characterized by SEM, AFM, XRD, 4-point-probe, and cyclic voltammertry. The optimal condition of Al-W was 10$0^{\circ}C$, 100W, 0.4Pa, 23sccm(Ar) and 35$0^{\circ}C$, 20min. annealing. At that condition the resistivity of Al-W(3 wt.%) was about 11$\mu$$\Omega$cm. And when wt.% of W in Al-W alloy was higher than about 4%, Al-W alloy thin film has high chemical resistance.

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Resistance Development in Au/YBCO Thin Film Meander Lines under High-Power Fault Conditions (과도 사고 시 Au/YBCO 박막 곡선의 저항 거동)

  • Kim, H.R.;Sim, J.;Choi, I.J.;Yim, S.W.;Hyun, O.B.
    • Progress in Superconductivity
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    • v.8 no.1
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    • pp.81-86
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    • 2006
  • We investigated resistance development in $Au/YBa_2Cu_3O_7(YBCO)$ thin film meander lines during high-power faults. The meander lines were fabricated by patterning 300 nm thick YBCO films coated with 200 nm thick gold layers into meander lines. A gold film grown on the back side of the substrate was also patterned into a meander line. The front meander line was connected to a high-power fault-test circuit and the back line to a DC power supply. Resistance of both lines was measured during the fault. They were immersed in liquid nitrogen during the experiment. Behavior of the resistance development prior to quench completion could be understood better by comparing resistance of the front meander lines with that of the back. Quench completion point could be determined clearly. Resistance and temperature at the quench completion point were not affected by applied field strength. The experimental results were analyzed quantitatively with the concept of heat transfer within the meander lines/substrate and to the surrounding liquid nitrogen. In analysis, the fault period was divided into three regions: flux-flow region, region prior to quench completion, and region after quench completion. Resistance was calculated for each region, reflecting the observation for quench completion. The calculated resistance in three regions was joined seamlessly and agreed well with data.

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A Study on Unified Vector Control of Induction Motor (유도전동기의 통일적 벡터제어에 관한 연구)

  • Kim, Y.D.;Lee, D.C.
    • Journal of Power System Engineering
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    • v.5 no.3
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    • pp.95-103
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    • 2001
  • This study is applied to common induction motor, and vector control is realized by using an indirect type of induction motor which has a simple composition. In this study extended Kalman filter is used from control theoretical viewpoint, and primary resistance and secondary resistance which change according to the temperature of motor are simultaneously estimated. This paper aims to research an indirect vector control in which the secondary resistance obtained from this estimation is consistent with secondary flux. This estimation is made by on-line estimation, but on-line estimation is difficult because extended Kalman filter takes long time in computation time. So off-line estimation was made on the assumption that the variation of temperature in motor is slow temporally.

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