• Title/Summary/Keyword: general weakening

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A Driving Torque Prediction of Brushless DC Motor by Using the Measured Current Data (전류측정 데이터를 이용한 브러쉬 없는 직류전동기의 구동토크 예측)

  • 변영철;전혁수
    • Journal of the Korea Institute of Military Science and Technology
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    • v.2 no.2
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    • pp.242-250
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    • 1999
  • This paper presents an estimation scheme of the external torque applied on the motor by using measured motor input current when the IPM(Interior Permanent Magnet) rotor type BLDC motor operates with constant speed. In general, the BLDC motor is controlled by vector control method. If it could be operated at over critical speed, the control scheme must be modified to flux-weakening control method. The external torque applied on the motor using flux-weakening control method could not be calculated by conventional torque equation because the demagnetizing current Id exists in the motor input current. In this paper, the commonly used flux-weakening control method is studied and the modified torque estimation scheme is suggested. The estimation scheme has been verified by the simulations and experimental results.

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Clinical Report on the Patients Suffering from Neurogenical Bladder (신경인성 방광 환자 치험 2례)

  • Yu, Byeong-Chan;Han, Yeong-Ju;Chae, Eun-Yeong;Yun, Dam-Hee;Lee, Nam-Hun;Cho, Chung-Sik;Kim, Chul-Jung;Lee, Ji-Yeong
    • The Journal of Internal Korean Medicine
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    • v.25 no.3
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    • pp.677-683
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    • 2004
  • The following case studies illustrate the application of oriental medical treatment of patients diagnosed with neurogenical bladder. The outstanding symptoms of two cases were general weakening and voiding difficulty, urinary retention and lack of urine sense. In one case, neurogenical bladder was caused by an operation on the femur, and in the other case, by diabetes and anemia. Western medical treatment didnot have any effect in these cases, but after oriental medical treatment, self-voiding was possible. These resu1t suggest that oriental treatment should be considered for patients with neurogenical bladder.

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Design and Analysis of Axial Flux Permanent Magnet Synchronous Machine

  • Jo, Won-Young;Lee, In-Jae;Cho, Yun-Hyun;Koo, Dae-Hyun;Chun, Yon-Do
    • Journal of Electrical Engineering and Technology
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    • v.2 no.1
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    • pp.61-67
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    • 2007
  • In this article, a special kind of axial flux permanent magnet machine has proved to be suitable for high torque and low speed applications. An innovative design of the machine has been proposed in order to make the machine suitable for traction applications by means of field-weakening. The aim of this paper is to analyze, in general terms, the basic equations that describe the operating conditions of such machines. Optimal sizes for design can be obtained by calculating the power density and the air-gap flux density, etc.

The Study on Field Performance Test of Multi Branch Type Tie(GOLRY TIE) (다지형 침목 현장 성능평가에 관한 연구)

  • Kim, Hae-Gon;Suh, Dong-Seok;Kim, Nam-Hong;Lee, Syeung-Youl
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.162-166
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    • 2011
  • In railway, Tie supports rail and plays a role that distribute train load to the ballast. Also, Tie and ballast resist against external force and fix the track position. But, weakening resistance of ballast and tie cause vertical displacement of tie and track irregularity. For reinforcement of track stiffness and reduction of track irregularity, KORAIL has developed Multi Branch type tie(GLORY Tie) that reinforced resistance than general PCT and installed in order to test in the field. This study measured and analyzed lateral resistance of ballast, wheel load of rail, bending strain of rail foot, vertical displacement and vibration acceleration of tie in order to evaluate performance of Multi Branch type tie in the field. According to the results of test, Multi Branch tie is excellent than general tie about lateral resistance of ballast and vertical displacement of tie. And, gap of measurement value between Multi Branch type tie and general tie about wheel load of rail, bending strain of rail foot were very small.

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Two Cases of Correlation between Improvement of General Weakness Symptoms and DHEAS Level through Korean Medical Treatment (한방치료를 통한 허로환자의 증상개선과 DHEAS 수치개선의 연관성에 관한 증례보고 2례)

  • Lee, He-sol;Jun, Chan-young;Choi, You-kyung
    • The Journal of Internal Korean Medicine
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    • v.37 no.6
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    • pp.1059-1068
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    • 2016
  • Objectives: This study reports on the efficacy of treating patients with general weakness symptoms with Korean medicine. Methods: Two patients with general weakness symptoms were treated with Korean medical treatment modalities, including acupuncture, moxibustion, and herbal medicines. Blood tests, the visual analogue scale (VAS), and patients' complaints were used to assess the treatment effects. Results and Conclusions: dehydroepiandrosterone sulphate (DHEAS), DHEAS/cortisol index, VAS, and the patients' complaints improved after treatment. Korean medical treatment is effective in improving DHEAS and the DHEAS/cortisol index according to the improvements in the patients' conditions. However, more studies are required to validate its use with other patients.

Optimum Angle of Incidence for General Anteroposterior Radiographic Image According to Lordosis angle : For Obese People

  • Kwak, Jong Hyeok;Kim, Gyeong Rip;Cho, Hee Jung;Moon, Sung Jin;Lee, Eun Sook;Sung, Soon Ki
    • International Journal of Contents
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    • v.17 no.1
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    • pp.18-26
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    • 2021
  • The obesity leads to be the result of the weakening of anatomical structure as well as the gravity effect. And, the obesity interferes with normal sagittal balance and fails to maintain a straight posture with minimal energy. Therefore, the obesity can be an important factor in causing back pain by changing the lumbar lordosis. In this study, we will present an appropriate angle of incidence for obese people to reduce the image distortion of L4, L5 during a general anteroposterior radiography examination. To reduce image distortion according to the change of lordosis, the angle of incidence was applied 9 ° and 21 ° to L4 and L5 vertebra body when obesity and low back pain (LBP) perform the general anteroposterior radiography examination.

High performance velocity and position controller for spindle motor (스핀들용 유도 전동기 고성능 속도 및 위치 제어기)

  • 임충혁;유준혁;김동일;김성권
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.648-651
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    • 1996
  • Samsung Electronics has developed high performance velocity and position controller for induction motors, and succeeded in mass production for the first time in Korea. Dynamic performance and final control accuracy of the controller are equivalent to those of AC servo motor controller. At present, we adopted the controller as spindle motor drive for Samsung CNC systems, and expect its wide use in industry as general purpose velocity and position controller for induction motor.

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High Performance Velocity and position Controller for Spindle Motor (스핀들용 유도 전동기 고성능 속도 및 위치 제어기)

  • 유준혁
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.10a
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    • pp.11-14
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    • 1996
  • Samsung Electronics has developed high performance velocity and position controller for induction motors and succeeded in mass production for first time in Lorea. Dynamic performance and final control accuracy of the controller are equivalent to those of AC servo motor controller. At present we adopted the controller as spindle motor drive for Samsung CNC systems and expect its wide use in industry as general purpose velocity and position controller for induction motor.

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ENSO Response to Global Warming as Simulated by ECHO-G/S (ECHO-G/S에 나타난 기후변화에 따른 엘니뇨 변화 특성 분석)

  • Lee, Hyo-Shin;Kwon, Won-Tae;Ahn, Joong-Bae;Boo, Kyung-On;Ch, Yu-Mi
    • Atmosphere
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    • v.17 no.4
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    • pp.365-379
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    • 2007
  • Global warming may shift the properties and dynamics of ENSO. We study the changes in ENSO characteristics in a coupled general circulation model, ECHO-G/S. First, we analyse the mean state changes by comparing present day simulation and various high $CO_2$ climates. The model shows a little El Nino-like changes in the sea surface temperature and wind stress in the eastern tropical Pacific. As the mean temperature rises, the ENSO amplitude and the frequency of strong El Ninos and La Nina decrease. The analysis shows that the weakening of the oceanic sensitivities is related to the weakening of ENSO. In addition to the surface changes, the remote subsurface sea temperature response in the western Pacific to the wind stress in the eastern Pacific influences the subsequent ENSO amplitude. However, ENSO amplitude does not show linear response to the greenhouse gas concentrations.

Problem on the Governing Body of National Federation of Fisheries Cooperatives (NFFC) - from the perspective of the Honorary Office of NFFC President - (수산업협동조합중앙회장의 명예직화에서 본 지배구조의 문제점)

  • Jeon, Hyeong-Soo
    • The Journal of Fisheries Business Administration
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    • v.40 no.1
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    • pp.97-112
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    • 2009
  • The amendment of regulation affecting the Governing Body of NFFC (National Federation of Fisheries Cooperatives) has been known to the public in May 2008. Its essential points are as follow: 1) the President of NFFC shall be a non-standing officer. 2) the Full-Time Directors shall have the authority to deal with all subjects except for those especially reserved for the General Meeting or Board of Directors, while minimizing the authority of NFFC President. By providing this amendment, the government seeks to make the Governing body becomes professionalized and the management functions carried out by full-time professional board members. However, the amendment seems to pay no attention to the co-operative's identity and principles. In this context, five issues will be discussed: 1) Strengthening the separation between ownership and control of NFFC. 2) Weakening the authority of General Meeting. 3) The bounds of Audit Committee. 4) Consolidating the management control of the Full-Time Directors. 5) The loss of NFFC's Identity, followed by a summary and conclusion.

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