• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.2
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• pp.287-292
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• 2021

In this paper, we propose an efficient CNN application method by analyzing the effect of activation function on the failure diagnosis of the inductive motor stator. Generally, the main purpose of the inductive motor stator failure diagnosis is to prevent the failure by rapidly diagnosing the minute turn short. In the application of activation function, experiments show that the Sigmoid function is 23.23% more useful in accuracy of diagnosis than the ReLu function, although it is shown that ReLu has superiority in overall fixer failure in utilizing the activation function.

• Journal of the Semiconductor & Display Technology
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• v.18 no.4
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• pp.87-91
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• 2019

The diagnosis of the failure for the existing electrical facilities was based on regular preventive maintenance, but this preventive maintenance was limited in preventing a lot of cost loss and sudden system failure. To overcome these shortcomings, fault prediction and diagnostic techniques are critical to increasing system reliability by monitoring electrical installations in real time and detecting abnormal conditions in the facility early. As the performance and quality deterioration problem occurs frequently due to the increase in the number of users of the motor pump, the purpose is to build an intelligent control system that can control the motor pump to maximize the performance and to improve the quality and reliability. To this end, a vibration sensor, temperature sensor, pressure sensor, and low water level sensor are used to detect vibrations, temperatures, pressures, and low water levels that can occur in the motor pump, and to build a system that can identify and diagnose information to users in real time.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.183-186
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• 2008

Both structural analysis and hydraulic test have been conducted to confirm the burst characteristics of filament wound solid motor case. Failure criteria have been defined with bursting above 150% of MEOP and failure in the cylinder. The results of analysis showed that filament fiber in the cylinder should be broken at about 2088psig. From a hydraulic test the same failure mode and the level of 2200psig of burst pressure have been proved. With these results, it is verified that a filament wound case meets burst requirements.

• Aerospace Engineering and Technology
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• v.9 no.1
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• pp.72-77
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• 2010

A hydraulic test on a filament wound case of Kick-Motor was conducted to evaluate the structural stiffness degradation and to confirm the burst performance. Failure criteria have been defined with bursting above 150% of MEOP(Maximum Expected Operation Pressure) and failure in the cylinder. The analysis result showed that filament fiber in the cylinder should be broken at about 2088psig. From a hydraulic test it has been verified that composite case meets the failure requirements, and that the stiffness does not decrease even after a year since the manufacturing.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1249-1254
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• 2013

A torque control algorithm suitable for detecting an open circuit failure in which one of the three phases is unable to supply power to a motor in the permanent magnet synchronous motor is presented in this paper. When the failure occurs in the inverter, the output torque of motor is restricted. A new method which is implemented by using only a processor algorithm internally without any hardware redundancy circuit is proposed. A simulation and experimental study is carried out with a three phase inverter system to show the validity of the proposed method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.7
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• pp.631-635
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• 2007

Diagnostic, surge and ac breakdown tests are widely used to evaluate the insulation condition of stator winding in traction motor. Diagnostic test included ac current, tan delta and maximum partial discharge. The result of diagnostic test indicates that five kinds of stator windings are good condition. Surge test was peformed to confirm the healthy of turn insulation in stator windings. This test is very easy to detect the turn insulation failure between normal and defect stator windings. After completing the diagnostic test, ac breakdown test has conducted gradually increasing ac voltage, until the stator winding punctured. No. 5 stator windings failed near rated voltage of 18.9 kV The breakdown voltage of No. 1 stator windings was 13.0 kV The ac breakdown voltage of normal winding is about 1.45 times higher than that of defect windings. The failure was located in a line-end coil at the exit from the core slot.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.9
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• pp.105-109
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• 2022

In this study, the cause of the acceleration failure of Hyundai Motor's 2.0-liter CRDi engine was analyzed. We tried to find problems through MDA (Measuring Data Analyzer) based on data such as vehicle speed, air intake, and air-fuel ratio obtained during the actual driving process. As a result, it was analyzed that the failure of the EGR valve exceeded the NOx emission standard and caused a decrease in engine output. Through this study, it is possible to reduce the time and cost of unnecessary maintenance and repair, and it is expected that a rapid cause analysis will be possible in the case of new failure diagnosis in the future.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.8
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• pp.82-87
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• 2011

Induction motor is most widely used as the driving power in the industrial site. Induction motor current is composed of two parts, magnetizing current and load current. Load current uses energy what is doing the work. Load current varies with load variance but magnetizing current is constant, regardless of load variation. Magnetizing current needs for establishing the rotating magnetic field of induction motor and lags behind the voltage. Generally capacitor is used for power-factor compensation of inductive load. Self-excitation occurs when the capacitive reactive current from the capacitor is greater than the magnetizing current of the induction motor. When this occurs, excessive voltages can result on the terminals of the motor. This excessive voltage can cause insulation degradation and ultimately result in motor insulation failure. In this paper, we analyzed that how the magnetizing current and condenser current is operating at the allowable limit by the load variation. Condenser current is below allowable limit of magnetizing current but magnetizing current is above allowable limit at the lower load operation condition.

• Speech Sciences
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• v.7 no.1
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• pp.97-107
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• 2000

Motor aphasia is an affection frequently caused by insult of the left middle cerebral artery and usually accompanied by a large lesion involving the Broca's area and the adjacent motor and premotor areas. Therefore, a patient with motor aphasia commonly shows articulatory disturbances due to failure of the motor programing of speech sound. Objective assessment and treatment of phonologic programing is one of the important aspects of speech therapy in aphasic patients. We analyzed the speech disorders acompanied with motor aphasia in a 45-year-old man using a computerized sound spectrograph, Visi-$Pitch{\circledR}$, and Multi-Dimensional Voice $Program{\circledR}$. We concluded that a computerized speech analysis system is a useful tool to visualize and quantitatively analyse the severity and progression of dysarthria, and the effect of speech therapy.

• Journal of Korean Physical Therapy Science
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• v.13 no.2
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• pp.121-127
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• 2006

Consideration for therapy method and oral motor function character of children with cerebral palsy. Therapists who treat for feeding disorder children owing the regression of oral motor function are necessary to gain knowledge about dysfunction of sensing, perception and cognition with baffling to eat and inhibition of primitive reflex, oral anatomy and function, and motor control (trunk, head, positioning of the upper limbs and the lower limbs and muscle tone). Oral motor function program is a comprehensive rehabilitation program which requires systematized enforcement and collaborated attempts to physiotherapists, occupational therapists, speech therapists, psychotherapists. Especially, physical therapists are not accustomed to oral motor program, hoping to provide diffusely and apply new therapy approach method for many areas (bell's palsy, respiratory failure, speech articulation). It will comprise to study owing to holistic approach with clinic.