• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2307-2316
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• 2017

The aim of this paper is to provide an optimal design of in-wheel motor for an electric scooter (E-scooter) considering economical production. The preliminary development in-wheel motor, which has a direct-driven outer rotor type attached to the E-scooter's rear wheel without any gear, is introduced first. The objective of the optimal design of this in-wheel motor is to improve the output characteristics of the motor and to have a stator form to facilitate automatic winding. Response surface methodology was used for the optimal design and 2-dimensional finite element method was used for electro-magnetic field analysis. Experimental results showed that the designed and fabricated in-wheel motor could satisfy the required specifications in terms of speed, power, efficiency, and cogging torque.

• Journal of the Korean housing association
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• v.14 no.3
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• pp.165-174
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• 2003

The demand for one-room system house as a new type of house will increase gradually, and residents also tend to be diversified. However, a method of planning of planning of one-room system house was limited and unified. Current floor plans of the one-room don't utilize a benefit of open plan in small areas. The purpose of this study is to propose several guidelines for the planning of one-room system houses that correspond to residents' needs in order to facilitate the benefit of open plan such as efficiency and multi-purpose use in small area. For this, a field survey was carried out as case studies, with individual interviews, questionnaires, and actual survey including taking pictures. Subjects were 50 residents who living in one-room system houses in Busan. Space usage behavior of residents, residential satisfactions, and preference attitudes on the attached service facilities were analyzed. The results were synthesized to suggest several guidelines for planning of one-room system house.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.368-371
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• 2005

In this paper, a small band pass filter is designed using new probe type for wireless communication system. In order to provide a band pass filter which can be reduced in dimension, can be reduced in height, and can be surface-mounted. The filter was fabricated using $TE_{01{\delta}}$ mode dielectric resonator. The input/output probes are attached to coner portion of the rectangular metal cavity. Results of the manufactured filter$(12{\times}12{\times}8mm)$ show that the center frequency is 9.953GHz, the insertion loss is -2.98 dB, the 3dB-bandwidth is 15 MHz, and the lode Q is 663.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1599-1607
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• 2003

The characteristics of elastic waves emanated from crack initiation in 6061 aluminum alloy subjected to fatigue loading are investigated through experiments. The objective of the study is to determine the differences in the properties of the signals generated from fatigue test and also to examine if the sources of the waves could be identified from the temporal and spectral characteristics of the acoustic emission (AE) waveforms. The signals are recorded using nonresonant, flat, broadband transducers attached to the surface of the alloy specimens. The time dependence and power spectra of the signals recorded during the tests were examined and classified according to their special features. Six distinct types of signals were observed. The waveforms and their power spectra were found to be dependent on the crack propagation stage and the type of fracture associated with the signals. The potential application of the approach in health monitoring of structural components using a network of surface mounted broadband sensors is discussed.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.891-896
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• 2007

This paper contained the flight test calibration for the airspeed indicator and the altimeter of the light airplane ChangGong-91, which is the first type certified aircraft from Korean Ministry of Construction and Transportation, as a part of the flight test validation. The flight test for airspeed position error calibration was performed using tower fly by method in order to calibrate swivel head testboom which is attached to the right wing tip of the airplane, and using system to system method for airspeed indicator. The altimeter calibration was calculated using flight test data for airspeed calibration. The flight test was conducted at the basis of the 'Korean Airworthiness Standard' regulation of Korean Ministry of Construction and Transportation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.731-736
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• 2002

Impact is the most common type of dynamic loading conditions that give rise to impulsive forces and affects the vibrational characteristics of mechanical systems . Since the real impact force and acceleration at the contact surface are measured indirectly through the sensors, the measured outputs can be a little different from the real impact responses. In this study, the contact force model based on the Hertz law is proposed in order to predict the impact force correctly. To investigate the influence of the position of the sensor attached to the impacting bodies, the two kinds of sensors were used. Finally, the contact force model obtained by drop test was applied to predict the impact force between the moving part and the stopper in magnetic contactor.

• Journal of Biosystems Engineering
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• v.24 no.3
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• pp.253-258
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• 1999

This study was conducted to develop an automatic egg inspection system for detecting creaked eggs based on acoustic impulse response. This system includes a sound generator, a sound sensor with signal conditioner, and a computer. The sound generator that hit the sharp of the dull edges of an egg was constructed with a ceramic ball pendulum attached to a rotary type solenoid. The signal conditioner included a pre-amplifier and a digital signal processing (DSP) board. The parameters for distinguishing cracked and normal eggs were the area, the geometric centroid and the resonance frequency of power spectrum of the acoustic signal generated. An algorithm for on-line detection of the continuous transferring eggs was developed. The performance tests resulted with 91% success rate to separate cracked and normal eggs at the rate of 1 second per an egg.

• Journal of Korean Neurosurgical Society
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• v.29 no.5
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• pp.684-687
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• 2000

Primary anaplastic oligodendroglioma in brain stem is extremely rare. The authors present a case of a anaplastic oligodendroglioma arising from pons. A 29 year-old male patient was admitted because of cranial nerve palsy and visual disturbance. Neurological examination revealed bilateral sixth and left seventh cranial nerve plasies. Near-total resection of tumor mass was performed through midline suboccipital appraoch. Tumor was not related with choroid plexus and major vessels but it was firmly attached to the fourth ventricle floor. Tumor was considered to be arised from the tegmental portion of pons, growing dorsally into the 4th ventricle. Hitopathological exmination revealed primary anaplastic oligodendroglioma. Postoperative course was uneventful. The authors believe that this type of tumor with dorsally growing pattern can be successfully resected without major neurological deficit.

• Journal of Chest Surgery
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• v.25 no.10
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• pp.1102-1106
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• 1992

A 66-year-old male patient was admitted due to chest pain and dyspnea of 1 year duration, He had history of treatment for tuberculosis and pleurisy, about 40 years ago. At another hospital the patient underwnt closed thoracostomy drainage for six months, and thereafter the symptom gradually aggrevated. Under the diagnosis of chronic tuberculous empyema, decortication was performed. The peel attached to the posterolateral aspect of chest wall, there was an area of soft tissues with pale-brown discoloration, extending to intercostal muscles, but sparing overlying muscles. The biopsy specimen of the lesion was pathologically diagnosed as diffuse, large T-cell non-Hodgkin`s lymphoma. A review of the literature showed that malignant lymphoma of this type have been reported exclusively from Japan but never from other countries including Korea. After 1 year of followup period, the patient is well and stable.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1679-1683
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• 2005

This paper suggests the new type of a joint torque sensor which is attached at each joint of a manipulator for making compliance. Previous six axis force/torque sensors are high cost and installed end-effector of the manipulator. However, torque on links of previous an end-effector cannot be measured. We design a joint torque sensor that can be fully integrated with an actuator in order to measure applying torque of the manipulator. The sensor system is designed through the structural analysis. The proposed joint torque sensors are installed to the 6 DOF manipulator of a mobile robot for hazardous works and we implemented experiments of measuring applied torque to the manipulator. By the experiment, we proved that the proposed low-cost joint torque sensor gives acceptable performance when we control a manipulator.