• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.952-954
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• 2002

The effort for measuring the rotor vibration caused by the short of rotor winding or air-gap eccentricity has been carried on. This paper introduces on-line vibration monitoring technologies using search coils to measure flux for synchronous generators. A 3,300/6,600 (V), 150 [kW] synchronous generator is built, and search coils are designed and inserted in the wedges. Furthermore, air-gap eccentricity is analyzed by finite element method and compared with experiment tests. Induced voltages caused by different air-gap eccentricity on the search coils are compared as well.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.6
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• pp.888-893
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• 1998

In this paper, we present a magnetic levitation system which has not a gap sensor with sensor-less realization and stabilizing controller design. For measuring gap between magnet and levitated object we propose a gap sensorless method and adop two-degree-of-freedom controller for robust-ness and performence of the magnetic levitation system. From time responeses we confirm that the proposed sensorless method which can be applied to magnetic levitation system. Also the designed stabilizing controller has good disturbance rejection and reference tracking performance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.387-392
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• 2002

A portable mould oscillation analyzer with an integrated computer, developed by POSCO, records the movement of the mould in every spatial direction. The system uses the gap sensors to measure the mould movement (displacement) in two horizontal directions according to the mould narrow and broad faces and the vertical strokes in the four corners of mould. The gap sensor is a non-contacting minute displacement-measuring device using the principle of high frequency eddy current loss. The mould oscillation diagnostic system integrates the gap sensors, their converters and the industrial portable computer with plug-in data acquisition boards. In an own expert module, which is included in the diagnosis program, one can obtain much information about the mould oscillation equipment.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.3
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• pp.81-88
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• 1993

This report describes the experimental research on the flow phenomena of the aq uaous polymer solution within the Cuette flow of the concentric, cylinders type with a wide circular gap. We have investigated the phenomena of the fluid flow through torque measuring in the system that the inner cylinder is stationary and the outer one is rotating. Geometrical parameters of the system are the gap ratio of t/R$_{0}$=0.2 and Aspect ratio of l/t=100. The torque increases considerably in about 420-480RPM, So, it is considered a turbulent transition boundary, the higher plymer concentration is, the lower torque value is and the higher transition Reynolds number is. In each of the polymer concentration, the unstable boundary of torque, that is, idiosyncrasies of torque is observed around 220-280RPM. and the boundary is looked upon as a resonant vibration which is caused by the inner cylinder and tortional vibration of torque sensor.r.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.62
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• pp.89-95
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• 2001

This research developed a survey and analyzed the results on the basis of the SERVQUAL model and prior research of the service quality in MIS. The result of the analysis will maybe show that the gap between expectations and perceptions of users will have an negative Impact on the user satisfaction of IS. And outsourcing strategy will have an impact on the user gap. The most important outcome of this study is that service quality is an antecedent of IS users, and we should consider service quality in improving and measuring IS effectiveness

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2552-2554
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• 2001

This paper presents a front-end electronic circuits for signal detection on multi-gap resistive plate. The input to the circuit is the signal(voltage : -800mv, frequency : 20${\sim}$40MHZ, noise : 50mv, 1GHz) from the multi-gap resistive plate chamber and the output is the 5v pulse signal. The front-end electronic circuit consists of preamplifier, peak-detector, and comparator. Spice simulation show that the circuit has the better response time than the one of the conventional measuring instruments.

• Proceedings of the KIEE Conference
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• summer
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• pp.1127-1129
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• 2004

In this paper, a new approach detecting broken rotor bars in a squirrel-cage induction motor is proposed. The air-gap flux variation analysis was done using search coils inserted in stator slots when broken rotor bar conditions occur. An accurate modelling and analysis of air-gap flux variation in the induction motor are developed using finite-element(FE) software packages, and measuring the flux we made using search coils. In the FE analysis, the three-phase squirrel-gage induction motor with 380 [V], 5 [HP], 4 Poles, 1,742 [rpm] ratings is used.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.475-480
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• 2006

In this paper, a new approach for detecting broken rotor bars in a squirrel-cage induction motor is proposed. The air-gap flux variation analysis was done using search coils inserted in stator slots when broken rotor bar occurs. An accurate modeling and analysis of air-gap flux variation in the induction motor are developed using finite-element (FE) software packages, and measurement of the flux are made using search coils. The simulation was done for the induction motor with 380 [V], 5 [HP], 4 Poles, 1,742 [rpm] ratings using the commercial FE analysis tool. The simulation and experiment results can be useful for detecting the broken rotor bar of an induction motor.

• Journal of Information Technology Services
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• v.22 no.4
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• pp.159-169
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• 2023

The digital industry area based on digital technology is specialized and rapidly changing. This kind of change lead to a gap of understanding arises between the digital industry and the public. The digital industry is a trend that cannot be reversed, thus efforts to reduce the gap in understanding are necessary for positive social development in the future. This study aimed to find clues to reduce the gap in understanding by measuring the difference in perception between the public and the digital industry. To measure the difference in perception, this study applied the mutual orientation model proposed by McLeod and Chaffee(1973), As a result of the study, both groups agreed that the digital industry would make a positive contribution to the Korean economy in the future. However, it was confirmed that there was a possibility of mutual misunderstanding due to different views on the digital industry.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.1
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• pp.45-50
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• 2013

Recently, a method for detecting animal tinnitus objectively, gap prepulse inhibition of acoustic startling (GPIAS) were reported. However, the GPIAS method is difficult to be directly applied to human tinnitus research because measuring repeatedly startling responses evoked by more than 110 dB SPL acoustic stimuli for human is not easy. In this paper, the auditory late latency response (ALLR) measurement system which can measure conveniently evoked potentials involving the information about the brain cortical activity related with auditory psychologic phenomena such as a tinnitus has been implemented. By using the implemented system, 8 persons with normal hearing sense have been experimented to measure N1-P2 amplitudes of ALLRs evoked by gap prepulse based acoustic stimuli. Through the experimental results, the prepulse inhibitions of all the participants' N1-P2 responses have been observed and their characteristics were evaluated. And it is verified that our implemented system can be utilized as a device for researching and evaluating the objective tinnitus detection method in the future study.