• Title/Summary/Keyword: Negative resistance

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A 3V-50MHz analog CMOS continuous time current-mode filter with a negative resistance load

  • 현재섭;윤광섭
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.7
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    • pp.1726-1733
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    • 1996
  • A 3V-50MHz analog CMOS continuous-time current-mode filter with a negative resistance load(NRL) is proposed. In order to design a current-mode current integrator, a modified basic current mirror with a NRL to increase the output resistance is employed. the inherent circuit structure of the designed NRL current integrator, which minimizes the internal circuit nodes and enhances the gain bandwidth product, is capable of making the filter operate at the high frequency. The third order Butterworth low pass filter utilizing the designed NRL current integrator is synthesized and simulated with a 1.5.mu.m CMOS n-well proess. Simulation result shows the cutoff frequency of 50MHz and power consumption of 2.4mW/pole with a 3V power supply.

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A Study on the Voltage Controlled Negative-Resistance Circuits (전압제어부저항회의 구성에 관한 고찰)

  • 왕경석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.5 no.1
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    • pp.70-75
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    • 1980
  • In this paper, it presents that novel Voltage-Controlled Nagativd-Resistance Circuit which composed by two Current mirror, and this presumes, interprets Co-operation of Circuit. Indeed, its to increase the peak Voltage Vp, whch is done by inserting a Zener Diode in series with R-experimental results and to presents the various Negative-Resistance Characteristic Confirmed with Conincided Substantially presumed realization of Circuit corperation and Calculated was Checked through experiments.

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Linkage of the Kanamycin Resistance Gene with the Streptothricin Resistance Gene in Staphylococcus aureus SA2

  • Shin, Chul Kyo;Sung Hwan Im;Woo Koo Kim;Kyung Bo Moon
    • Journal of Microbiology and Biotechnology
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    • v.6 no.3
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    • pp.219-220
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    • 1996
  • The pKH2 isolated from the multidrug-resistant Staphylococcus aureus SA2 is a 40.98-kb plasmid and mediates resistance to ampicillin, clindamycin, erythromycin, kanamycin, and streptomycin. The 3.4-kb HindIII fragment conferring kanamycin resistance was cloned from the pKH2 into pBluescriptII $KS^+$ and partial sequence determination of that fragment was carried out. Sequence analysis revealed that the kanamycin resistance gene which encoded aminoglycoside 3'-phosphotransferase was linked to the streptothricin resistance gene. But a nonsense mutation was found in the streptothricin resistance gene and this mutation resulted in a truncated protein of streptothricin acetyltransferase. Homology comparison with nucleotide sequence databases revealed that the 3.4-kb HindIII fragment of pKH2 had been derived not from S. aureus but from Gram-negative Campylobacter coli.

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Factors Influencing Resistance to the Metaverse: Focusing on Propagation Mechanisms

  • Mina Lee;Minjung Kim
    • International journal of advanced smart convergence
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    • v.13 no.2
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    • pp.110-118
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    • 2024
  • This study examines factors influencing nonusers' resistance to the adoption of the metaverse, focusing on propagation mechanisms. It elucidates the role of innovation resistance within the metaverse adoption process. We applied the Innovation Resistance Model in the context of the metaverse and considers three major groups of factors influencing resistance to the metaverse: innovation characteristics (perceived usefulness, compatibility, perceived risk, and complexity), consumer characteristics (personal innovativeness), and propagation mechanisms (mass media, online media, and personal communication). An online survey of college students who do not use the metaverse revealed that perceived usefulness, compatibility, personal innovativeness, and online media were negative predictors of resistance to the metaverse. Conversely, perceived risk, mass media, and personal communication were positive predictors of resistance to the metaverse. Furthermore, innovation resistance was found to play a mediating role in the metaverse adoption process. Drawing upon the findings, we suggested marketing strategies to decrease resistance to the metaverse.

Characterization of bft Genes among Enterotoxigenic Bacteroides fragilis Isolates from Extraintestinal Specimens at a University Hospital in Korea (국내 한 대학병원의 임상검체에서 분리된 Bacteroides fragilis 독소 유전자의 특성)

  • Kim, Myungsook;Kim, Hyunsoo;Ji, Seung Eun;Rim, John Hoon;Gwon, Sun Yeong;Kim, Wan Hee;Rhee, Ki-Jong;Lee, Kyungwon
    • Korean Journal of Clinical Laboratory Science
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    • v.48 no.2
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    • pp.82-87
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    • 2016
  • Enterotoxigenic Bacteroides fragilis (ETBF) produces enterotoxins known to be a virulence factor. Three isotypes of the B. fragilis toxin (BFT) gene have been identified: bft-1, bft-2, and bft-3. We investigated the presence of bft isotypes in clinical B. fragilis isolates and the antimicrobial resistance of BFT-negative and BFT-positive isolates. Overall, 537 B. fragilis isolates were collected from extraintestinal specimens over 8 years (2006~2013) from a university hospital in Korea. Samples were analyzed by multiplex PCR to identify the bft gene isotypes. Additionally, the antimicrobial susceptibility of 107 B. fragilis isolates (74 BFT-negative and 33 BFT-positive) was examined by the CLSI agar dilution method. PCR revealed a total bft gene detection rate of 30%, while 33% and 29% of blood and other extraintestinal isolates contained the gene, respectively. Among ETBF isolates, the most common isotype was bft-1 gene, followed by bft-2 and bft-3 (bft-1 77%, bft-2 14%, bft-3 9%). Resistance rates (%) for BFT-negative and positive isolates differed in response to various antimicrobial agents, with 3%, 5%, 1% and 38% of BFT-negative isolates and 3%, 6%, 3% an 42% of BFT-positive isolates being resistant to piperacillin-tazobactam, cefoxitin, imipenem, and clindamycin, respectively. Interestingly, neither BFT-negative nor positive isolates showed antimicrobial resistance to chloramphenicol and metronidazole. Overall, the proportion of ETBF from blood was similar to that of other extraintestinal sites and the bft-1 gene was the predominant isotype. Higher antimicrobial resistance rates were found in BFT-positive isolates than BFT-negative isolates, but these differences were not statistically significant.

Antimicrobial resistance rates changes according to the amount of the antimicrobial agent in clinically important strain isolated from blood cultures (혈액배양에서 분리된 임상적 주요 균주의 항균제사용량에 따른 내성률 변화)

  • Kim, Jae-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.653-659
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    • 2016
  • The purpose of the study is to investigate the correlation between the amount of antimicrobial agent (Defined Daily Dose, DDD) and antimicrobial resistance rate (%). The treatment of infectious diseases is becoming increasingly difficult, due to the increase in the number of multi-drug resistant bacteria, making it a clinically significant problem. Among the various factors, antimicrobial abuse is a major cause of antimicrobial resistance. The study was conducted on inpatients in a secondary university hospital in the central region utilizing the hospital's computerized statistical data and microbiological program of laboratory medicine from January 2010 to December 2014 pertaining to the dose of antimicrobial drugs for Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli strains isolated from blood culture. We analyzed the antimicrobial resistance rate per dose with the Pearson correlation coefficient. A significant (positive?) correlation was detected between the cefepime dose and the resistance of E. coli (P<0.033; r=0.907), while a significant negative correlation was found between the tobramycin dose and the resistance of E.coli. (P<0.028; r=-0.917). The aminoglycoside resistance of A. baumannii showed a significant negative correlation (P<0.048; r=-0.881), and the aminoglycoside resistance of E. coli showed a significant negative correlation as well (P<0.001; r=-0.992). In conclusion, the amount of antimicrobial agent (Defined Daily Dose, DDD) (is partly related to) the bacterial strain and its antimicrobial resistance rate (%).

An Exploration on Prescription of Resistance Training for Geriatric Physical Therapy (노인물리치료를 위한 저항트레이닝 처방에 대한 탐색)

  • Shin Hong-Cheul;Jeong Dong-Hyuk
    • The Journal of Korean Physical Therapy
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    • v.15 no.1
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    • pp.61-81
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    • 2003
  • There can be little dissension that the ultimate goal of all physical therapy interventions with the elderly is to restore or maintain the highest level of function possible for the individual. Whenever physical therapists take on this challenge, they assist elders in maintaining their identities as competent adults. Advancing age is associated with profound changes in body composition, including increased fat mass, decreased fat-free mass(particularly muscle), decreased total body water and decreased bone density. Along with these changes in body compositions, and perhaps as a direct result of them, elderly people have lower energy needs, reduced strength and functional capacity and a greatly increased risk for such diseases as noninsulin-dependent diabetes mellitus and osteoporosis. Resistance training is considered a promising intervention for reversing the loss of muscle function and the deterioration of muscle structure that is associated with advanced age. This reversal is thought to result in improvements in functional abilities and health status in the elderly by increasing muscle mass, strength and power and by increasing bone mineral density. In the past couple of decades, many studies have examined the effects of Resistance training on risk factors for age-related diseases or disabilities. We have explored the positive and negative aspects of older adults' participation in resistance training programs. The benefits to older adults are reported to be increased strength, endurance, muscle capacity, and flexibility; more energy; and improved self-image and confidence. The negative aspects include some pain or stiffness and other nonspecific problems. The positive and negative aspects of resistance training are therefore very similar to those in younger populations. Scientific investigations over the past 10 years have demonstrated that resistance training can be safely and successfully implemented in older populations. Even the frail and very sick elderly can benefit and improve their quality of life. Proper design and progression of a resistance training program for older adults is vital to optimal benefits from resistance exercise. The results of data provided by this research on resistance training for health shows that there is enough existing evidence to conclude that resistance training, particularly when incorporated into a comprehensive fitness program, can offer substantial health benefits which can be obtained by persons of all ages. These benefits, including improvements in functional capacity, translate into an improved quality of life.

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Fungicide Resistance and Genetic Diversity of Botrytis cinerea of Citrus (감귤 잿빛곰팡이병균의 살균제에 대한 저항성 및 유전적 다양성)

  • 고영진;이재군;서정규;문두길;한해룡
    • Korean Journal Plant Pathology
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    • v.14 no.6
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    • pp.682-688
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    • 1998
  • Fungicide resistance of 48 isolates of Botrytis cinerea collected from citrus in Cheju was investigated and genetic diversity was analyzed with random amplified polymorphic DNA(RAPD). High levels of resistance to benzimidazole fungicides benomyl and thiophanate-methyl and N-phenylcarbamate fungicide diethofencarb were observed. Negative cross resistance was clear between benzimidazole and N-phenylcarbamate fungicides, and multiple resistance to the fungicides was also observed. There was cross resistance among the dicarboximide fungicides procymidione, vinclozolin and iprodione as it was observed between the benzimidazole fungicides benomyl and thiophanate-methyl. The lowest levels of resistance were to the dicarboximide fungicides, but no sensitive isolate to polyoxin B was observed. The isolates showed genetically diverse RAPD profiles according to the geographic origin collected, but there was no significant correaltion between RAPD profiles of genomic DNA and the levels of fungicide resistance of the isolates. The isolates showed genetically diverse RAPD profiles, indicating that genetic differentiation had already occurred in the populations of B. cinerea distributed in Cheju.

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Analysis of Pile Behaviors with Friction Resistance of Skin of Steel Pipe Pile in Ground where Settlement is Predicted (침하가 예측되는 지반에서 강관말뚝 주면 마찰 저항에 따른 말뚝의 거동 분석)

  • Lee, Kicheol;Shin, Sehee;Lee, Haklin;Kim, Dongwook
    • Journal of the Korean Geotechnical Society
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    • v.36 no.11
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    • pp.107-117
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    • 2020
  • Open-ended steel pipe piles have outside frictional force and inside frictional resistance in which blocked soil acts on the inside of the steel pipe during installation. It is expected that the ultimate load will change depending on the inside and outside resistance. And, if the ground on which the piles were constructed is clay soil, it is predicted that it will have effect on the negative skin friction caused by the ground settlement. Therefore, in this study, the behavior according to the inside and outside resistance characteristics of steel pipe piles was analyzed numerically, and the frictional force distribution, axial load and settlements before and after the occurrence of ground settlement were calculated. As a result of the analysis, the inside frictional resistance had less influence than the outside frictional resistance. However, inside frictional resistance is considered to be one of the important factors considering the effect on the overall pile behavior, and both resistance factors need to be considered in the design process.

Optimization for Permeability and Electrical Resistance of Porous Alumina-Based Ceramics

  • Kim, Jae;Ha, Jang-Hoon;Lee, Jongman;Song, In-Hyuck
    • Journal of the Korean Ceramic Society
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    • v.53 no.5
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    • pp.548-556
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    • 2016
  • Recently, porous alumina-based ceramics have been extensively applied in the semi-conductor and display industries, because of their high mechanical strength, high chemical resistance, and high thermal resistance. However, the high electrical resistance of alumina-based ceramics has a negative effect in many applications due to the generation of static electricity. The low electrical resistance and high air permeability are key aspects in using porous alumina-based ceramics as vacuum chucks in the semi-conductor industry. In this study, we tailored the pore structure of porous alumina-based ceramics by adjusting the mixing ratio of the starting alumina, which has different particle sizes. And the electrical resistance was controlled by using chemical additives. The characteristics of the specimens were studied using scanning electron microscopy, mercury porosimetry, capillary flow porosimetry, a universal testing machine, X-ray diffraction, and a high-resistance meter.