• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.605-609
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• 2000

This paper presents a development of the Pulse Width Modulation ASIC for control of the AC servo or spindle motor in machine tools. The ASIC is designed two PWM functions for simultaneous control of a converter and an inverter. Also the device includes additionally two UART functions for interfacing the RS232C with PC or other devices. The device is connected to the microprocessor of Intel or Motorola by bus interface. The required output voltage and frequency for the motor control is programmed to the PWM block and the corresponding switching signals are calculated and generated with regard to the programmed value.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.119-119
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• 2000

In this research an induction motor vector control system was developed using Simulink and RTW(Real Time Workshop). On the Simulink window, control system is designed in the form of block diagrams, program codes are produced automatically with the RTW, then c compiler compiles the program codes. With this automatic real time program producing mechanism rapid prototyping is realized without the time-consuming manual program coding procedures. To show effectiveness of the proposed designing scheme a DSP-based induction motor vector control system was constructed and implemented

• Journal of Mechanical Science and Technology
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• 제16권8호
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• pp.1095-1101
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• 2002

The load characteristics of engine main bearing are very important in the design of crankshaft and engine block. The stiffness of crankshaft and block, or the optimal dimension of the bearing can be determined according to the load level. This paper presents the load characteristics of engine main bearing. Two components of the main bearing load are measured during engine firing and motoring. The vertical and horizontal load components are measured by using the dynamic load cell mounted in each main bearing cap bolt. The measured main bearing loads are compared with calculated results by using the statically determinate method. The theoretical results, provided in this study, agreed well with the experimental results. The presented results are very useful for achieving optimal design of engine.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 춘계종합학술대회
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• pp.324-329
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• 1999

This paper proposes new torque control of an induction motor, which is robust against time verying parameters. The control is based on adaptive vector control with serial block adaptive algorithm. Motor parameters used to estimates slip frequency and torque. Frequency mismatch in the control system detrimentally affects slip frequency estimation and torque response. In order to compensate for degradation of the responses an adaptive identifier for the magnetizing inductance and the secondary time constand is introduced. adaptive vector control system consisted of two subsystems, a vector control system realized on synchronous frame and a parameter identification system on stationary frame. the effectiveness of the proposed method was verified by some digital simulations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.647-650
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• 2001

In case of bent axis type axial piston hydraulic pump or motor, hydrostatic bearing used to achieve the lubrication effect on the mechanical sliding contact areas between the following pairs ; piston shoe and swash plate, valve plate and cylinder block, piston and cylinder block, etc. In this research, we designed two pairs of spherical ball joint in witch connecting rod piston end. The one is not hydrostatic bearing, the other is designed with spherical hydrostatic bearing in point of view minimum pumping power loss. By varying supply pressure on the piston, we can know that it is possible to reduce the friction torque by using hydrostatic bearing designed one. Finally, by comparing the results of driving torque between the two models, it was verified that the spherical hydrostatic bearing is well designed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.988-991
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• 2003

In this paper, we try to develop the controller which uses the block diagrams of SIMTool and internal functions CEMTool for planning the global driving controller for high efficiency AGV. We acquire the control efficiency by controlling the motor used each part of AGV driving controller. The block diagram structures provided with SIMTool is easily designed by the controller, and the monitoring and analysis of the results is researched by simulation. We expect to control AGV. robot and various plant using Ziegler-Nichols auto-tuning method and external I/O board

• Annals of Clinical Neurophysiology
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• 제19권1호
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• pp.3-12
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• 2017

Using threshold tracking, differences have been established between large myelinated sensory and ${\alpha}$ motor axons in humans. Major differences are that sensory axons are relatively depolarised at rest such that they have a greater persistent $Na^+$ current, and have greater activity of hyperpolarisation-activated cyclic nucleotide-gated (HCN) channels. Sensory axons may thereby be protected from hyperpolarising stresses, and are less likely to develop conduction block. However, the corollary is that sensory axons are more excitable and more likely to become ectopically active.

• Annals of Clinical Neurophysiology
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• 제8권1호
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• pp.102-105
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• 2006

We present a case with stepwise weakness and sensory involvement of both hands for more than 2 months. His nerve conduction study findings revealed prolonged terminal latencies, decreased motor and sensory conduction velocities and conduction blocks of both ulnar nerves, more severely on left side. And there were other abnormalities manifested with mononeuropathy multiplex. Increased cerebrospinal fluid protein was found. We diagnosed him as Lewis-Sumner syndrome and tried high dose oral steroid therapy for 2 months. He showed improvement of motor functioning with persistent conduction block.

• ETRI Journal
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• 제37권6호
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• pp.1176-1187
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• 2015

This work proposes a highly efficient sensorless motor driver chip for various permanent-magnet synchronous motors (PMSMs) in a wide power range. The motor driver chip is composed of two important parts. The digital part is a sensorless controller consisting mainly of an angle estimation block and a speed control block. The analog part consists of a gate driver, which is able to sense the phase current of a motor. The sensorless algorithms adapted in this paper include a sliding mode observer (SMO) method that has high robust characteristics regarding parameter variations of PMSMs. Fabricated SMO chips detect back electromotive force signals. Furthermore, motor current-sensing blocks are included with a 10-bit successive approximation analog-to-digital converter and various gain current amplifiers for proper sensorless operations. Through a fabricated SMO chip, we were able to demonstrate rated powers of 32 W, 200 W, and 1,500 W.

• The Korean Journal of Pain
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• 제18권1호
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• pp.85-88
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• 2005

Encephalitis is known as a rare complication of varicella zoster virus (VZV) reactivation. It is usually regarded as a complication of a cutaneous infection in patients with impaired cellular immunity. The reported incidence of herpetic motor involvement range between 0.5 and 31%, but is possibly more frequent as the weakness is readily obscured by pain. A 53-years-old woman, who presented with severe shoulder pain, fever, headache and seizure, which developed the day after skin eruptions, also developed motor paresis 7 days after the seizure. Her cerebrospinal fluid (CSF) was VZV-Polymerase chain reaction (PCR) negative, but VZV specific IgG antibody positive, and her brain MRI was found to be normal. With the early diagnosis and proper treatment, such as intravenous administration of acyclovir, stellate ganglion block and Yamamoto New Scalp Stimulation (YNSS), the patient completely recovered, without psychoneurological sequelae. Herein, we present this case, with a discussion of the relevant literature on the incidence, pathophysiology, diagnosis and management of central nervous system VZV involvement.