• Title/Summary/Keyword: E.coil

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Design and Manufacture for the 0.7MJ SMES Coil (0.7MJ SMES Coil 설계 및 제작)

  • Kim, H.J.;Seong, K.C.;Cho, J.W.;Lee, E.Y.;Ryu, K.S.;Ryu, K.
    • Proceedings of the KIEE Conference
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    • 1998.07a
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    • pp.140-142
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    • 1998
  • The major part of SMES (Superconducting Magnetic Energy Storage) system consist of the superconducting coil, cryostat and current lead, power converter. The 0.7MJ SMES coil was a design and manufacture by using SMES device that we developed a design code. A SMES coil was wound with high winding tension in order to prevent wire motion from Lorentz force. This paper described optimum design for the SMES coil.

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Development of Coil Breakage Prediction Model In Cold Rolling Mill

  • Park, Yeong-Bok;Hwang, Hwa-Won
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1343-1346
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    • 2005
  • In the cold rolling mill, coil breakage that generated in rolling process makes the various types of troubles such as the degradation of productivity and the damage of equipment. Recent researches were done by the mechanical analysis such as the analysis of roll chattering or strip inclining and the prevention of breakage that detects the crack of coil. But they could cover some kind of breakages. The prediction of Coil breakage was very complicated and occurred rarely. We propose to build effective prediction modes for coil breakage in rolling process, based on data mining model. We proposed three prediction models for coil breakage: (1) decision tree based model, (2) regression based model and (3) neural network based model. To reduce model parameters, we selected important variables related to the occurrence of coil breakage from the attributes of coil setup by using the methods such as decision tree, variable selection and the choice of domain experts. We developed these prediction models and chose the best model among them using SEMMA process that proposed in SAS E-miner environment. We estimated model accuracy by scoring the prediction model with the posterior probability. We also have developed a software tool to analyze the data and generate the proposed prediction models either automatically and in a user-driven manner. It also has an effective visualization feature that is based on PCA (Principle Component Analysis).

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Equivalent Mechanical and Thermal Properties of Multiphase Superconducting Coil Using Finite Element Analysis (유한요소해석을 이용한 다상의 초전도 코일에 대한 기계적 열적 등가 물성)

  • Sa, J.W.;Her, N.I.;Choi, C.H.;Oh, Y.K.;Cho, S.;Do, C.J.;Kwon, M.;Lee, G.S.
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.975-980
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    • 2001
  • Like composite material. the coil winding pack of the KSTAR (Korea Superconducting Tokamak Advanced Research) consist of multiphase element such as metallic jacket material for protecting superconducting cable, vacuum pressurized imprepregnated (VPI) insulation, and corner roving filler. For jacket material, four CS (Central Solenoid) Coils, $5^{th}$ PF (Poloidal Field) Coil, and TF (Toroidal Field Coil) use Incoloy 908 and $6-7^{th}$ PF coil, Cold worked 316LN. In order to analyze the global behavior of large coil support structure with coil winding pack, it is required to replace the winding pack to monolithic matter with the equivalent mechanical properties, i.e. Young's moduli, shear moduli due to constraint of total nodes number and element numbers. In this study, Equivalent Young's moduli, shear moduli, Poisson's ratio, and thermal expansion coefficient were calculated for all coil winding pack using Finite Element Method.

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Mechanism of Glycogen Biosynthesis by Glycogen Synthetase from Escherichia coil B (Escherichia coil B의 Glycogen Synthetase반응에 의한 글리코겐 생합성기작)

  • 양지영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.6
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    • pp.1173-1176
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    • 1998
  • Glycogen synthetase[EC 2.4.1.21] in E. coli B was isolated and purified by sonication, ultracentri fugation, DEAE cellulose chromatography and gel chromatography. In the case of using glycogen or maltotriose as a primer in the enzyme reaction, 64% and 23.7% of labelled ADP glucose were incorporated into primer, respectively. 8.1% of labelled ADP glucose was polymerized into glycogen in enzymatic reaction without a primer.

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Quench Characteristic of the Model Coil for a $\mu$ SMES Magnet ($\mu$ SMES 마그네트용 모델 코일의 ?치 특성)

  • 김해종;성기철;조전욱;김석환;이언용;권영길;류강식;류경우
    • Progress in Superconductivity and Cryogenics
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    • v.3 no.2
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    • pp.5-9
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    • 2001
  • For the development of a small-sized superconducting magnetic energy storage($\mu$SMES) system we designed, fabricated and tested a model coil consisting of five coils with different features. e.g. winding tensions. bore diameters and materials. cooling channels. The results show that even in the highly pre-stressed small coil the quench currents of the coils are degraded to about 70% of their coils critical current. The quench currents of the coils with natrow cooling channels are two times as high as that of the coil without spacers. The test results also indicate that the usual training effect depends on the winding tensions of the coils according to materials of the bobbin.

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Linearity study for the field coil current and the load of eddy current dynamometer (Eddy current 동력계의 부하와 와전류의 직진성 관련 연구)

  • 문병수
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2000.04a
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    • pp.66-72
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    • 2000
  • Commercial eddy current dynamometers control the torque of ratating body (poer supply machine) with the field coil current being operated as a braking force. In this paper, we studied about the relation between the field coil current and the torque load of eddy current dynamometer. By the torque measuring analysis of eddy current dynamometer, it is linear relation between the brake force measured from the torque meter (e.g. load cell, strain gage or spring balance etc.) which is installed at the case of dynamometer and the multiply of shaft rpm by the square of field coil current (N$\times$Ia2). To prove the relation, it was experimented and showed that the torque operated by the rotating body can be measured with the shaft rpm and the field coil current of eddy current dynamometer. This result shows a possibility that eddy current dynamometer can measures the torque of rotating body without special torque measuring devices.

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Dynamic Characteristics of Moving Coil type Linear Oscillatory Actuator(LOA) (가동코일형 리니어 액튜에이터의 동특성)

  • Jang, S.M.;Kweon, C.;Jeong, S.S.;Sung, S.Y.;Ryu, D.W.;Yoon, I.K.
    • Proceedings of the KIEE Conference
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    • 1999.07a
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    • pp.15-17
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    • 1999
  • A voice-coil-type LOA consists of the NdFeB permanent magnets with high specific energy as the stator, a coil-wrapped nonmagnetic hollow rectangular structure. We have to obtain the back-EMF constant ${\kappa}_E$ from 3D FEA and experiments, precisely. The ${\kappa}_E$ and other parameters provide the transfer function, through which is derived the frequency response characteristics. Inverter-fed LOA is examined aiming to compare with results of simulation.

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A Study on Transcranial Magnetic Electrode Simulation Using Maxwell 3D (Maxwell 3D를 이용한 경두개 자기 전극 시뮬레이션에 관한 연구)

  • Lee, Geun-Yong;Yoon, Se-Jin;Jeong, Jin-hyoung;Kim, Jun-Tae;Lee, Sang-sik
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.12 no.6
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    • pp.657-665
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    • 2019
  • In this study, we conducted a study on the transcranial magnetic electrode, a method for the study of dementia and muscle pain, a neurodegenerative disease caused by an aging society, which is becoming a problem worldwide. In particular, transcranial magnetic electrodes have been studied to improve their ability to be deteriorated by dementia symptoms such as speech, cognitive ability, and memory by outputting magnetism deep into the brain using coils on the head epidermis. In this study, simulation was performed using Maxwell 3D program for the design of coil, the core of transcranial magnetic electrode. As a result of the simulation comparison between the coil designed by the previous research and the coil through the research and development, the output was found to be superior to the conventional designed coil. The graphs of the coil outputs of B-Field and H-Field are found to be symmetrical, but the symmetry between each coil is pseudo-symmetrical and not accurate. Based on these results, an experiment was conducted to confirm whether the output of the head epidermis through both coils is possible. In the magnitude field of the reverse-coil 2-coil analysis, the maximum output was 3.3920e + 004 H [A_per_meter], and the vector field showed the strongest magnetic field around 35 to 165 degrees. It was confirmed that the magnetic output canceled due to the magnetic output. In the case of the forward 2-coil, a maximum of 3.2348e + 004H [A_per_meter] similar to the reverse coil was observed, but in the case of the vector field, the magnetic output regarding the forward output and the head skin output was confirmed. However, when the height change in the output coil, the magnetic output was reduced.

Studies on Enterotoxigenic Escherichia coli Isolated from Cattle (우(牛) 유래(由來) 장독소(腸毒素) 산생(産生) 대장균(大腸菌)에 대하여)

  • Lee, Gang-log;Choi, Won-pil
    • Korean Journal of Veterinary Research
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    • v.26 no.1
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    • pp.69-77
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    • 1986
  • The purpose of this study was the examination for presence of K99 antigen (K99), enterotoxigenicity, 0-groups, colicin and antibiotic susceptibility among E. coil isolated from calves and cows. A total of 49(18.7%) among 262 strains, isolated from 30(26.5%) out of 113 calves and cows, possesed K99, and thirty three of 49 $K99^+$ strains produced ST. Of the strains of diarrheal calf origin which less than 15 days old, a high correlation was observed between enterotoxigenic ability and K99: 92.3% of the $K99^+$ strains produced heat stable enterotoxin(ST). In O group typing of 33 $ST^+$ strains, they belonged to O20(48.4%), O8(9.1%), O9(6.1%), O139(6.1%), O149(6.1%), O101(3.0%), O115(3.0%), except six which were untypable or autoagglutinable. Of 262 E. coil isolates, 30 strains(13.3%) produced colicin and K99 were detected in 6 strains. One hundred eighty eight strains(71.8%) of 262 E. coil isolates were resistance to ampicillin, chloramphenicol, gentamicin, kanamycin, streptomycin, tetracycline, alone or in combination thereof. One hundred and fourteen(60.6%) out of 188 drug resistance strains carried R factor($R^+$) which were transferable to the recipients by conjugation. Sixty five $R^+$ strains(57.0%) carried thermo-sensitive R plasmid.

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The Effects of Porphyromonas endodontalis Lipopolysaccharide on Production of Several CC Chemokines by Periodontal Ligament Fibroblast (Porphyromonas endodontalis의 lipopolysaccharide가 치주인대 섬유아세포의 CC Chemokines 성성에 미치는 영향)

  • KO Hyun-Jung;Lee Sang-Yup;Lee Woo-Chul;Baek Seung-Ho;Bae Kwang-Sik;Lim Sung-Sam
    • The Journal of the Korean dental association
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    • v.43 no.12 s.439
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    • pp.799-808
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    • 2005
  • 이 연구의 목적은 치수 및 치근단 조직의 감염의 주요 원인들이 Porphyromonas endodontalis의 LPS가 치주인대 섬유아세포의 MCP-1 MIP-1α 그리고 RANTES의 생성에 미치는 영향을 관찰함으로써 치근단 염중의 발병에서 섬유아세포의 역할을 알아보는 것이다. 혐기성 조건에서 배양한 P. endodontalis와 E. coil의 LPS를 추출, 정제한 후, 치주인대 섬유아세포 0.01, 0.1, 1, 10ug/ml 농도의 P. endodontalis와 E. coil의 LPS로 12, 24, 48시간 동안 자극하였다. MCP-1, MIP-1α 그리고 RANTES의 단백질 농도는 ELISA를 이용하여 분석하였다. 이연구의 결과는 아래와 같다. 1. P. endodontalis의 LPS로 자극시킨 치주인대 섬유아세포에서 분비된 MCP-1의 수준은 시간과 농도에 비례하여 증가하였다. 2.E.coil의 LPS로 자극시킨 치주인대 섬유아세포에서 분비된 MCP-1의 양도 시간에 비례하여 증가함을 보였다. 이는 P. endodontalis LPS보다 통계적으로 유의성있게 많은 양을 나타냈다.(p<0.05) 3. 치주인대 섬유아세포에서 MIP-1α 과 RANTES는 거의 분비되지 않았다. 이 연구에서 세균의 LPS로 자극시 치주인대 섬유아세포 MCP-1의 강한 발현은 만성 치근단 염증의 초기에 단핵세포와 대식세포의 recruitment를 증가시키는 것고 관련되어지는 것으로 보인다.

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