• Title/Summary/Keyword: resistance diagnosis

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Open Circuit Fault Diagnosis Using Stator Resistance Variation for Permanent Magnet Synchronous Motor Drives

  • Park, Byoung-Gun;Kim, Rae-Young;Hyun, Dong-Seok
    • Journal of Power Electronics
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    • v.13 no.6
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    • pp.985-990
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    • 2013
  • This paper proposes a novel fault diagnosis scheme using parameter estimation of the stator resistance, especially in the case of the open-phase faults of PMSM drives. The stator resistance of PMSMs can be estimated by the recursive least square (RLS) algorithm in real time. Fault diagnosis is achieved by analyzing the estimated stator resistance of each phase according to the fault condition. The proposed fault diagnosis scheme is implemented without any extra devices. Moreover, the estimated parameter information can be used to improve the control performance. The feasibility of the proposed fault diagnosis scheme is verified by simulation and experimental results.

The Use of Skin Resistance Point Finder for the Diagnosis of Myofascial Trigger Points (피부 저항점 탐지기를 사용한 근근막 통증 유발점의 진단)

  • Kang, Mi-Suk;Hong, Jung-Eun;Lim, Young-Jin;Lee, Sang-Chul
    • The Korean Journal of Pain
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    • v.12 no.2
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    • pp.195-199
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    • 1999
  • Background: At present, there is no reliable objective test for the diagnosis of myofascial trigger points (MFTP). We evaluated the usefulness of skin resistance point finder for the diagnosis of MFTP. Methods: 40 subjects with clinical MFTPs at the upper trapezius muscle were included in this study. Using skin resistance point finder (UNIQUE S-2010$^{(R)}$, Seik medical, Korea), we tried to find out the point of low skin resistance. At three different current level, sensitivity and specificity of this method for the diagnosis of clinically identified MFTP was evaluated. Pressure threshold for pain of low skin resistance point was measured using Pressure Threshold Meter$^{(R)}$ (Pain Diagnostics and Thermography, U.S.A.). 3 groups of point detected at different current were compared in mean pressure threshold. Results: Fixed single current of skin resistance point finder showed variable sensitivity and specificity. But, by adjusting current level, skin resistance point finder detected all of 40 clinically identified MFTPs. Although it is partially statistically significant, the mean pressure threshold of points detected at high current was high. Conclusion: Skin resistance finder can be used as objective diagnostic tool of MFTPs. There is possibility that it can be useful in evaluating treatment effect. However, more investigation is necessary.

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Self-Diagnosis for Fracture Prediction of Concrete Reinforced by New Type Rib CFGFRP Rod and CF Sheet (신형 리브재 CFGFRP 보강근 및 CF 보강시트로 보강된 콘크리트의 파괴예측 자가진단)

  • Park, Seok-Kyun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.27 no.2
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    • pp.115-123
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    • 2007
  • For investigating self-diagnosis applicability, a method based on monitoring the changes in the electrical resistance of carbon fiber reinforced concrete has been tested. Then after examining change in the value of electrical resistance at each flexural weight-stage of carbon fiber in CFGFRP (carbon fiber and glass fiber reinforcing plastic) with new type rib and carbon sheet for concrete reinforcing, the correlations of electrical resistance and load as a function of strain, deflection were analyzed. As the results, it is clarified that when carbon fiber rod, rib and sheet fracture, the electrical resistance of it increase largely, and specially in case of CFGFRP, afterwards glass fiber tows can be resist the load due to the presence of the hybrid (carbon and glass) reinforced fiber. Therefore, it can be recognized that reinforcing bar and new type rib of CFGFRP and sheet of CF could be applied for self-diagnosis of fracture in reinforced FRP concrete.

Applicability of Hyblid FRP Reinforcing Bar for Self-diagnosis of Concrete Fracture (콘크리트 파괴 자가진단을 위한 하이브리드 FRP 보강근의 적용 특성)

  • Park, Seok-Kyun;Kim, Dae-Hoon
    • Journal of the Korea Concrete Institute
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    • v.18 no.3 s.93
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    • pp.439-445
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    • 2006
  • For investigating self-diagnosis applicability, a method based on monitoring the changes in the electrical resistance of hybrid FRP(having electrical property) reinforced concrete has been tested. Then after examining change in the value of electrical resistance of carbon fiber in CFRP(non-hybrid type), CFGFRP and CFAFRP(hybrid type) before and after the occurrence of cracks and fracture in non-hybrid and hybrid FRP reinforced concrete at each flexural weight-stage, the correlations of each factors(the changes in electrical resistance and load as a function of strain, deflection) were analyzed. As the results, it is clarified that when the carbon fiber tows fracture, the electrical resistance of it increase largely, and afterwards hybrid FRP composites can be resist the load due to the presence of the reinforced fiber, for example, glass fiber or aramid fiber tows. Therefore, it can be recognized that hybrid FRP(including carbon fiber) reinforcing bar could be applied for self-diagnosis of fracture in reinforced FRP concrete fracture.

An Electromyographic Study of the Efficacy of Mandibular Movement Esercise on Opening Limitation (개구제한시 하악운동연습의 효과에 관한 근전도학적 연구)

  • Chang-Kwon Song;Kyung-Soo Han;Ho-In Jung
    • Journal of Oral Medicine and Pain
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    • v.17 no.1
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    • pp.61-71
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    • 1992
  • 52 Dental students without masticatory problems were selected for this study. They were trained on several mandibular position and mandibular movement exercise, that is, rest position, light bite, tapping, hinge opening, habitual opening, opening limitation, stretch exercise, resistance exercise and clenching. The objectives of this study was to investigate the effects of mandibular movement exercise, especially stretch and resistance, on the experimentally guided limited mouth opening. Muscle activity of the anterior temporalis and the masseter on above mentioned position or exercise were recorded with bioelectric processor EM2(Myotronics, U.S.A.) and the data were processed with SPSS. The obtained results were as follows : 1. Activity of the muscles at rest position were decreased with mandibular movement exercise. 2. Forceful mouth opening on opening limitation increased muscle activity greatly, especially of the masseter. 3. On opening limitation, stretch or resistance exercise was very efficient for decrease of muscle activities. 4. There were no difference of muscle activity between on hinge opening and on habitual opening. Therefore, for muscle relaxation, the two movement exercise can be used interchangeably.

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Frequency Analysis Method Based Fault Diagnosis of an Electrolytic Capacitor for Voltage Smoothing (주파수 분석기법을 이용한 전압 평활용 전해 커패시터의 고장진단)

  • Shon, Jin-Geun;Kim, Jin-Sik
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.58 no.2
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    • pp.207-213
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    • 2009
  • Electrolytic capacitors have been widely used in power electronics system because of the features of large capacitance, small size, high-voltage, and low-cost. Electrolytic capacitors, which is most of the time affected by aging effect, plays a very important role for the power electronics system quality and reliability. Therefore it is important to estimate the parameter of an electrolytic capacitor to predict the failure. This paper proposed a novel fault diagnosis method of an electrolytic capacitor used for voltage smoothing in boost DC converter. The equivalent series resistance(ESR) of electrolytic capacitor estimated from FFT result of filtered waveform of capacitor voltage/current. Main advantage of the proposed method include circuit simplicity and easy implementation. Simulation and experimental results are shown to verify the performance of the proposed method.

Fault Diagnosis of a Electrolytic Capacitor for Inverter DC-Link Voltage Smoothing (인버터 직류링크 전압 평활용 전해 커패시터의 고장 진단)

  • Lee, Kwang-Woon
    • The Transactions of the Korean Institute of Power Electronics
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    • v.12 no.5
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    • pp.372-377
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    • 2007
  • This paper proposes a novel fault diagnosis method of a electrolytic capacitor used for DC-link voltage smoothing in adjustable speed drives. The equivalent series resistance (ESR) of the electrolytic capacitor is directly estimated from DC-link voltage and load currents and the status of the electrolytic capacitor is determined from the estimated ESR. To compensate the variation of the ESR owing to temperature variation, diodes are located on the same PCB near the capacitor and the temperature of the capacitor is sensed indirectly from the voltage drop of diodes. Simulation and experimental studies show the effectiveness of the proposed method.

Diagnosis of Benzimidazole Resistance in Haemonchus contortus of Sheep by Allele Specific PCR

  • Tiwari, J.;Kolte, A.P.;Kumar, S.;Swarnkar, C.P.;Singh, D.;Pathak, K.M.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.1
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    • pp.7-11
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    • 2007
  • The study was conducted on 162 adult male Haemonchus contortus of sheep collected from Avikanagar, Jaipur and Bikaner regions to diagnose the benzimidazole (BZ) resistance in H. contortus. The BZ resistance is primarily linked with the mutation in ${\beta}$-tubulin isotype 1 gene which substitute phenylalanine (Phe) into tyrosine (Tyr) at the 200 codon of the gene. An allele specific polymerase chain reaction (AS-PCR) technique was used for diagnosis of BZ resistance in H. contortus. In AS-PCR, one reverse primer (TGG 312) was used in two separate reactions with each of 2 forward primers (resistant TGG 331 and susceptible CAW 106 primer) that differed only at 3' nucleotide position. Therefore, the amplified products from resistant and susceptible parasites were produced 267 and 266 bp, respectively. A total of 162 parasites were genotyped, of which 130 parasites found homozygous resistant 'rr', 22 heterozygous 'rS' and 10 homozygous susceptible 'SS' type. The prevalence of 'rr' individuals was higher in Jaipur (98%) followed by Avikanagar (93%) and Bikaner (50%) regions. Overall, the prevalence of BZ resistant allele (r) was higher (87%) as compared to 13% of BZ susceptible allele (S).

Development of Aging Diagnosis Device Through Real-time Battery Internal Resistance Measurement

  • Kim, Sang-Bum;Lee, Sang-Hyun
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.2
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    • pp.129-135
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    • 2022
  • Currently, the rapid growth of electric vehicles and the collection and disposal of waste batteries are becoming a social problem. The purpose of this paper is to propose a fast and efficient battery screening method through a safe inspection and storage method according to the collection and storage of waste batteries of electric vehicles. In addition, as the resistance inside the waste battery increases, an instantaneous voltage drop occurs, and there is a risk of overcharging and overdischarging compared to the initial state of the battery. Accordingly, there are great difficulties in operation, so the final goal of this study is to develop a device for diagnosing aging through real-time battery internal resistance measurement. Final result As a result of simulation of the internal resistance measurement test circuit through external impedance (AC), the actual simulation value was 0.05Ω, RS = Vrms / Irms => Vrms = 8.0036mV, Irms = 162.83Ma. Substitute the suggested method. The result was calculated as Rs = 0.0495Ω. It is possible to measure up to 64 impedances inside the aging diagnostic equipment that enables real-time monitoring of the developed battery cells, and the range can be changed according to the application method.

Clinical characteristics in Taiwanese women with polycystic ovary syndrome

  • Hsu, Ming-I
    • Clinical and Experimental Reproductive Medicine
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    • v.42 no.3
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    • pp.86-93
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    • 2015
  • Polycystic ovary syndrome (PCOS) is one of the most common hormonal endocrine disorders in women of reproductive age. It consists of a heterogeneous collection of signs and symptoms that together form a disorder spectrum. The diagnosis of PCOS is principally based on clinical and physical findings. The extent of metabolic abnormalities in women with PCOS varies with phenotype, body weight, age, and ethnicity. For general population, the prevalence of hyperandrogenism and oligomenorrhea decreases with age, while complications such as insulin resistance and other metabolic disturbances increase with age. Obese women with PCOS have a higher risk of developing oligomenorrhea, amenorrhea, hyperandrogenemia, insulin resistance, and lower luteinizing hormone (LH) to follicle stimulation hormone (FSH) ratios than non-obese women with PCOS. The LH to FSH ratio is a valuable diagnostic tool in evaluating Taiwanese women with PCOS, especially in the diagnosis of oligomenorrhea. Overweight/obesity is the major determinant of cardiovascular and metabolic disturbances in women of reproductive age.