• Title/Summary/Keyword: search-coil

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MUSIC-based Diagnosis Algorithm for Identifying Broken Rotor Bar Faults in Induction Motors Using Flux Signal

  • Youn, Young-Woo;Yi, Sang-Hwa;Hwang, Don-Ha;Sun, Jong-Ho;Kang, Dong-Sik;Kim, Yong-Hwa
    • Journal of Electrical Engineering and Technology
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    • v.8 no.2
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    • pp.288-294
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    • 2013
  • The diagnosis of motor failures using an on-line method has been the aim of many researchers and studies. Several spectral analysis techniques have been developed and are used to facilitate on-line diagnosis methods in industry. This paper discusses the first application of a motor flux spectral analysis to the identification of broken rotor bar (BRB) faults in induction motors using a multiple signal classification (MUSIC) technique as an on-line diagnosis method. The proposed method measures the leakage flux in the radial direction using a radial flux sensor which is designed as a search coil and is installed between stator slots. The MUSIC technique, which requires fewer number of data samples and has a higher detection accuracy than the traditional fast Fourier transform (FFT) method, then calculates the motor load condition and extracts any abnormal signals related to motor failures in order to identify BRB faults. Experimental results clearly demonstrate that the proposed method is a promising candidate for an on-line diagnosis method to detect motor failures.

An Experimental Study on the heat transfer characteristics and performance of storage tanks with mantle heat exchanger (맨틀형 축열조의 열전달 성능 및 특성에 관한 실험적 연구)

  • Kang, Y.H.;Kwak, H.Y.;Yoon, H.G.;Yoo, C.G.;Yoon, H.S.;Chun, W.G.
    • Journal of the Korean Solar Energy Society
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    • v.21 no.1
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    • pp.61-69
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    • 2001
  • The heat transfer characteristics of horizontal and vertical mantle heat storage tanks are studied in order to replace the tank-coil heat exchanger for application in thermosyphon solar water heaters. In this study, 5 mantle storage tanks with different geometric shape are manufactured into stainless steel and each tank is tested. For the test, The inlet flow rate of the heat transfer fluid is maintained 1.2 lpm consistently. The heat transfer fluid temperature through the mantle is $70{\pm}1^{\circ}C$. The temperatures of 26 points included the ambient temperature are measured at every one minute. The measured data are used to calculate the overall heat transfer coefficient(UA) using the LMTD(Log Mean Temperature Difference) method and it is used on the analysis of the heat transfer characteristics to search for optimum arrangement.

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DEVELOPMENT OF MAGNETOMETER DIGITAL CIRCUIT FOR KSR-3 ROCKET AND ANALYTICAL STUDY ON CALIBRATION RESULT (KSR-3 과학 로켓용 자력계 디지털 회로 개발 및 검교정시험 결과 분석 연구)

  • 이은석;장민환;황승현;손대락;이동훈;김선미;이선민
    • Journal of Astronomy and Space Sciences
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    • v.19 no.4
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    • pp.293-304
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    • 2002
  • This paper describes the re-design and the calibration results of the MAG digital circuit onboard the KSR-3. We enhanced the sampling rate of magnetometer data. Also, we reduced noise and increased authoritativeness of data. We could confirm that AIM resolution was decreased less than InT of analog calibration by a digital calibration of magnetometer. Therefore, we used numerical-program to correct this problem. As a result, we could calculate correction and error of data. These corrections will be applied to magnetometer data after the launch of KSR-3.

A Single Nucleotide Polymorphism in LOC534614 as an Unknown Gene Associated with Body Weight and Cold Carcass Weight in Hanwoo (Korean Cattle)

  • Lee, Y.S.;Oh, D.Y.;Kim, J.J.;Lee, J.H.;Park, H.S.;Yeo, J.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.12
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    • pp.1543-1551
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    • 2010
  • A major aim of cattle genome research is to identify candidate genes associated with meat quantity and quality through QTL analysis for application in the livestock industry. Therefore, this study focused on discovery of useful SNPs within the LOC534614 gene, containing 12273_165 SNP which is located on the same site as the QTL on chromosome 6, and evaluation of the association between SNP and body weight and cold carcass weight in Hanwoo (Korean cattle) As a result of a BLAST search of the NCBI web site, we discovered that the mRNA sequence of the LOC534614 gene was similar to that of the coiled-coil domain containing 158 (CCDC158) for dog and human. According to the direct DNA sequence from the CCDC158 gene, we identified 19 polymorphic SNPs within exons and their flanking regions. Among them, 17 polymorphic SNPs were selected for genotyping in Hanwoo (n = 476) and seventeen marker haplotypes containing 12273_165 SNP (frequency >0.1) were identified. As a result of the association between 17 polymorphic SNPs and Hanwoo (n = 476), g.8778G>A SNP in exon 6 was found to be a non-synonymous SNP, and was significantly associated with body weight and cold carcass weight (p<0.05). We discovered 19 polymorphic SNPs in the CCDC158 gene on the QTL region of BTA 6 in Hanwoo and identified that the g.8778G>A SNP was significantly associated with body weight and cold carcass weight (p<0.05), which causes an amino acid variation from valine to methionine. Furthermore, statistical analysis demonstrated that the CCDC158 gene is strongly associated with body weight and cold carcass weight in Hanwoo. In this regard, the g.8778G>A SNP in the CCDC158 gene can be useful as a positional candidate for body weight and cold carcass weight for marker-assisted selection in Hanwoo.

PRELIMINARY REPORT: DESIGN AND TEST RESULTS OF KSR-3 ROCKET MAGNETOMETERS

  • Kim, Hyo-Min;Jang, Min-Hwan;Lee, Dong-Hun;Ji, Jong-Hyun;Kim, Sun-Mi;Son, De-Rac;Hwang, Seung-Hyun
    • Journal of Astronomy and Space Sciences
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    • v.17 no.2
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    • pp.317-328
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    • 2000
  • The solar wind contributes to the formation of unique space environment called the Earth's magnetosphere by various interactions with the Earth's magnetic field. Thus the solar-terrestrial environment affects the Earth's magnetic field, which can be observed with an instrument for the magnetic field measurement, the magnetometer usually mounted on the rocket and the satellite and based on the ground observatory. The magnetometer is a useful instrument for the spacecraft attitude control as well as the Earth's magnetic field measurements for the spacecraft purpose. In this paper, we present the preliminary design and test results of the two onboard magnetometers of KARI's (Korea Aerospace Research Institute) sounding rocket, KSR-3, which will be launched four times during the period of 2001-02. The KSR-3 magnetometers consist of the fluxgate magnetometer, MAG/AIM (Attitude Information Magnetometer) for acquiring the rocket flight attitude information, and of the search-coil magnetometer, MAG/SIM (Scientific Investigation Magnetometer) for the observation of the Earth's magnetic field fluctuations. With the MAG/AIM, the 3-axis attitude information can be acquired by the comparison of the resulting dc magnetic vector field with the IGRF (International Geomagnetic Reference Field). The Earth's magnetic field fluctuations ranging from 10 to 1,000 Hz can also be observed with the MAG/SIM measurement.

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Ground-based Observations of the Polar Region Space Environment at the Jang Bogo Station, Antarctica

  • Kwon, Hyuck-Jin;Lee, Changsup;Jee, Geonhwa;Ham, Young-Bae;Kim, Jeong-Han;Kim, Yong Ha;Kim, Khan-Hyuk;Wu, Qian;Bullett, Terence;Oh, Suyeon;Kwak, Young-Sil
    • Journal of Astronomy and Space Sciences
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    • v.35 no.3
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    • pp.185-193
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    • 2018
  • Jang Bogo Station (JBS), the second Korean Antarctic research station, was established in Terra Nova Bay, Antarctica ($74.62^{\circ}S$ $164.22^{\circ}E$) in February 2014 in order to expand the Korea Polar Research Institute (KOPRI) research capabilities. One of the main research areas at JBS is space environmental research. The goal of the research is to better understand the general characteristics of the polar region ionosphere and thermosphere and their responses to solar wind and the magnetosphere. Ground-based observations at JBS for upper atmospheric wind and temperature measurements using the Fabry-Perot Interferometer (FPI) began in March 2014. Ionospheric radar (VIPIR) measurements have been collected since 2015 to monitor the state of the polar ionosphere for electron density height profiles, horizontal density gradients, and ion drifts. To investigate the magnetosphere and geomagnetic field variations, a search-coil magnetometer and vector magnetometer were installed in 2017 and 2018, respectively. Since JBS is positioned in an ideal location for auroral observations, we installed an auroral all-sky imager with a color sensor in January 2018 to study substorms as well as auroras. In addition to these observations, we are also operating a proton auroral imager, airglow imager, global positioning system total electron content (GPS TEC)/scintillation monitor, and neutron monitor in collaboration with other institutes. In this article, we briefly introduce the observational activities performed at JBS and the preliminary results of these observations.

The Optimization and Numerical Analysis of The Antenna Circuit for Antenna Design With 13.56MHz As Transmitting Wireless Power (무선전력 전송용 13.56MHz의 안테나 설계를 위한 안테나 회로의 최적화 및 수치적 해석)

  • Chung, Sung-In;Lee, Seung-Min;Lee, Hug-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.10
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    • pp.57-62
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    • 2009
  • This study proposes the optimization and numerical analysis of the antenna circuit for antenna design with 13.56 MHz as transmitting wireless power, for calculating the dose radiation exposure to the real time. The 13.56 MHz of the antenna frequency bands is used to the loop antenna which is a induced current for transmitting the power with wireless the reader to the tag. The study compared to the real measurement value as calculating the value of the inductance and capacitance through the numerical analysis for the antenna LC resonance using the theory of the electromagnetic induction method. We tried to search for the resonance point as the voltages of both sides of antenna coil by the scope measures of the peak point, as we tried to be variable the resonance capacitor for the optimization tuning of the antenna circuit and the matching of the antenna port. We convince our research contributes to help the design and application technology of the wireless power transmit system which is received power supply with wireless.

A Study for Detecting a Gazing Point Based on Reference Points (참조점을 이용한 응시점 추출에 관한 연구)

  • Kim, S.I.;Lim, J.H.;Cho, J.M.;Kim, S.H.;Nam, T.W.
    • Journal of Biomedical Engineering Research
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    • v.27 no.5
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    • pp.250-259
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    • 2006
  • The information of eye movement is used in various fields such as psychology, ophthalmology, physiology, rehabilitation medicine, web design, HMI(human-machine interface), and so on. Various devices to detect the eye movement have been developed but they are too expensive. The general methods of eye movement tracking are EOG(electro-oculograph), Purkinje image tracker, scleral search coil technique, and video-oculograph(VOG). The purpose of this study is to embody the algorithm which tracks the location of the gazing point at a pupil. Two kinds of location data were compared to track the gazing point. One is the reference points(infrared LEDs) which is effected from the globe. Another is the center point of the pupil which is gained with a CCD camera. The reference point was captured with the CCD camera and infrared lights which were not recognized by human eyes. Both of images which were thrown and were not thrown an infrared light on the globe were captured and saved. The reflected reference points were detected with the brightness difference between the two saved images. In conclusion, the circumcenter theory of a triangle was used to look for the center of the pupil. The location of the gazing point was relatively indicated with the each center of the pupil and the reference point.

Screening for candidate genes related with histological microstructure, meat quality and carcass characteristic in pig based on RNA-seq data

  • Ropka-Molik, Katarzyna;Bereta, Anna;Zukowski, Kacper;Tyra, Miroslaw;Piorkowska, Katarzyna;Zak, Grzegorz;Oczkowicz, Maria
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.10
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    • pp.1565-1574
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    • 2018
  • Objective: The aim of the present study was to identify genetic variants based on RNA-seq data, obtained via transcriptome sequencing of muscle tissue of pigs differing in muscle histological structure, and to verify the variants' effect on histological microstructure and production traits in a larger pig population. Methods: RNA-seq data was used to identify the panel of single nucleotide polymorphisms (SNPs) significantly related with percentage and diameter of each fiber type (I, IIA, IIB). Detected polymorphisms were mapped to quantitative trait loci (QTLs) regions. Next, the association study was performed on 944 animals representing five breeds (Landrace, Large White, Pietrain, Duroc, and native Puławska breed) in order to evaluate the relationship of selected SNPs and histological characteristics, meat quality and carcasses traits. Results: Mapping of detected genetic variants to QTL regions showed that chromosome 14 was the most overrepresented with the identification of four QTLs related to percentage of fiber types I and IIA. The association study performed on a 293 longissimus muscle samples confirmed a significant positive effect of transforming acidic coiled-coil-containing protein 2 (TACC2) polymorphisms on fiber diameter, while SNP within forkhead box O1 (FOXO1) locus was associated with decrease of diameter of fiber types IIA and IIB. Moreover, subsequent general linear model analysis showed significant relationship of FOXO1, delta 4-desaturase, sphingolipid 1 (DEGS1), and troponin T2 (TNNT2) genes with loin 'eye' area, FOXO1 with loin weight, as well as FOXO1 and TACC2 with lean meat percentage. Furthermore, the intramuscular fat content was positively associated (p<0.01) with occurrence of polymorphisms within DEGS1, TNNT2 genes and negatively with occurrence of TACC2 polymorphism. Conclusion: This study's results indicate that the SNP calling analysis based on RNA-seq data can be used to search candidate genes and establish the genetic basis of phenotypic traits. The presented results can be used for future studies evaluating the use of selected SNPs as genetic markers related to muscle histological profile and production traits in pig breeding.

Specific Effects on Monocular OKN Directional Asymmetry of Unilateral Microinjections of GABA Antagonist into the Mesencephalic Structures in the Chicken (OKN을 유발하는 단축 Mesencephalic 구조에 GABA Antagonist를 미량 주입할 때의 닭의 OKN 방향적 불균형성에 관한 특수효과)

  • 김명순
    • The Korean Journal of Zoology
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    • v.39 no.1
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    • pp.1-11
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    • 1996
  • The SR 95531, a GABA antagonist was microinjected into either the pretectum nuclei (nucleus Superficialis Synencephali nSS) or the nBOR (nucleus Ectomammilaris nEM) of chickens. Monocular optokinetic nystagmus (01(N) was reorded by the search coil technique before and after unilateral intracerebral drug administration. Unilateral microinjections of SR 95531 into either the nSS or nEM induce a reversible increase of gain in OKN directed by contralateral eye for both directions of stimulation. The administration into the nSS increased directional asymmetry by increasing the T~ component velocity gain more strongly than the N-T component velocity gain. On the other hand, the unilateral administration of the drug into the nEM suppressed the diretional O1(N asymmetry by increasing the N-T component velocity gain more strongly than the T-N component velocity gain. The nSS seems especially involved in monocular OKN in response to a T-N stimulation, while the nEM seems more involved in the OKN response to N-T stimulation. These results indicate that the drug suppresses GABAergic inhibition at the mesencephalic level. The increase in gain of OKN directed by the ipsilateral eye to microinjeded nuclei could account for the strong interactions existing between these two mesencephalic structures responsible for horizontal OKN.

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