• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.137-142
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• 1998

This paper describes a simple vector control scheme for the wound rotor type induction motors(WRIM) without the additional speed sensor in order to remove the external resistor bank which is usually adapted for the WRIM speed control. The motor angular speed is obtained indirectly from the slip angular speed is obtained indirectly from the slip angular speed and the slip angular speed is estimated by detecting the rotor currents only. Because the motor parameters are not included in the estimation algorithm, the proposed algorithm is free from the variation of the motor parameters and the robust sensorless vector control can be achieved. The performance of the proposed scheme is verified through the digital simulation.

• Proceedings of the KIEE Conference
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• 1998.07f
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• pp.1993-1995
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• 1998

The compensation problem of error and various problems due to delay of speed sensor itself and speed detection have issued in case using speed sensor in the adjustable speed control of induction motor. This paper have applied the stator flux oriented vector control algorithm and space voltage vector PWM method in order to improve an dynamic character of voltage-source inverter system, and also used the better IP controller in the speed response than Pl controller as speed controller. This paper estimated the rotator speed using input current of inductor motor and flux component invoked through voltage drop by terminal voltage and stator resistor.

• The Journal of the Acoustical Society of Korea
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• v.34 no.5
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• pp.351-359
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• 2015

Typical underwater acoustic transducers detect only the magnitude of an acoustic pressure and they have the limitation of not being able to recognize the direction of the sound signal. Hence, the authors of this paper proposed a new vector sensor structure based on Tonpilz transducers that could detect both the magnitude and the direction of a sound pressure. In the proposed structure, the piezoceramic ring was divided into four segments, and proper combination of the output voltages of the segments in response to the external sound pressure could provide the information on the orientation of the sound source. In this paper, a Tonpilz transducer has been fabricated to have the proposed structure and its characteristics has been measured to confirm the validity of the proposed structure.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.5 no.1
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• pp.45-51
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• 2012

In this paper, it's a system which recognize the user's emotions after obtaining the biological informations(pulse sensor, blood pressure sensor, blood sugar sensor etc.) about user's bio informations through wireless sensors in accordance of previously collected informations about user's stress index and classification the Colors & Music. This system collects the inputs, saves in the database and finally, classifies emotions according to the stress quotient by using multiple SVM(Support Vector Machine) algorithm. The experiment of multiple SVM algorithm was conducted by using 2,000 data sets. The experiment has approximately 87.7% accuracy.

• Journal of Sensor Science and Technology
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• v.24 no.1
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• pp.47-53
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• 2015

Fall-related injuries in elderly people are a major health care problem. This paper introduces determination of fall direction before impact using support vector machine (SVM). Once a falling phase is detected, dynamic characteristic parameters measured by the accelerometer and gyroscope and then processed by a Kalman filter are used in the SVM to determine the fall directions, i.e., forward (F), backward (B), rightward (R), and leftward (L). This paper compares the determination sensitivities according to the selected parameters for the SVM (velocities, tilt angles, vs. accelerations) and sensor attachment locations (waist vs. chest) with regards to the binary classification (i.e., F vs. B and R vs. L) and the multi-class classification (i.e., F, B, R, vs. L). Based on the velocity of waist which was superior to other parameters, the SVM in the binary case achieved 100% sensitivities for both F vs. B and R vs. L, while the SVM in the multi-class case achieved the sensitivities of F 93.8%, B 91.3%, R 62.3%, and L 63.6%.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.1
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• pp.74-86
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• 2014

The optimization techniques are explored in the direction of arrival (DOA) estimation based on single acoustic pressure gradient vector sensor (APGVS). By analyzing the working principle and measurement errors of the APGVS, acoustic intensity approaches (AI) and the minimum variance distortionless response beamforming approach based on single APGVS (VMVDR) are deduced. The radius to wavelength ratio of the APGVS must be not bigger than 0.1 in the actual application, otherwise its DOA estimation performance will degrade significantly. To improve the robustness and estimation performance of the DOA estimation approaches based on single APGVS, two modified processing approaches based on single APGVS are presented. Simulation and lake trial results indicate that the performance of the modified approaches based on single APGVS are better than AI and VMVDR approaches based on single APGVS when the radius to wavelength ratio is not bigger than 0.1, and the two modified DOA estimation methods have excellent estimation performance when the radius to wavelength ratio is bigger than 0.1.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.8
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• pp.1820-1826
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• 2013

Heterogeneous field sensor network between sensor to sensor is designed the CAN method to bus type structure in most using at industry. This Network is supporting a distance vector routing protocol on a characteristic structural a bus type. Also This network support to convert as making separate routing table in heterogeneous network. However distance vector routing protocol make a problem of decrease efficiency because of restriction of network expandability and low transmission process. We propose new CAN routing protocol to support network expandability and high transmission process of industry network. New CAN routing protocol structure addition priority and optional function field based on RIPv2. We established heterogeneous field sensor network, we measure data Throughput(bits/sec) for confirm new CAN routing protocol to increase efficient in industry.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.2055-2058
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• 2004

This paper formulates a yaw angle determination algorithm for earth-point satellite. The algorithm based on vector observation, is implemented with the limited vector measurements. The proposed algorithm doesn't require gyro measurement data but magnetic sensor measurement data. In order to confirm the usefulness of the proposed method, we investigate the simulated telemetry data of the KOMPSAT-2, a satellite that is scheduled to be launched into a 685km altitude sun synchronous circular orbit in 2005.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2521-2524
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• 2003

Since inertial sensor errors which increase with time are caused by initial orientation error and sensor errors (accelerometer bias and gyro drift bias), the accuracy of these devices, while still improving, is not adequate for many of today's high-precision, long-duration sea, aircraft, and long-range missile missions. This paper presents a navigation error compensation scheme for Strap-Down Inertial Navigation System (SDINS) using Line-Of-Sight(LOS) vector from star sensor. To be specific, SDINS error model and measurement equation are derived, and Kalman filter is implemented. Simulation results show the bounded-ness of position and attitude errors.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1366-1370
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• 2010

This paper supposes the vector control algorithm to estimate the rotor position of permanent magnet synchronous traction motor using the hall-effect sensor. The hall-effect provides 60 electrical degrees resolution in rotor position sensing and it is very low resolution. The algorithm makes resolution high as optical encoders or electromagnetic resolver. If necessary, the reference rotor position angle is controlled by adjusting the variable. When a rotor position sensor such as either a optical encoder or a electromagnetic resolver is misalignment, it is useful to align with those. The method on adjusting the reference rotor position angle can compensate for misalignment error degrees by 60 electrical degrees.