• The Transactions of the Korean Institute of Electrical Engineers B
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• v.48 no.6
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• pp.330-335
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• 1999

This paper proposed the p-q-r coordinate system where the instantaneous active power p, and the two instantaneous reactive powers qq, qr were defined. The three power components are linearly independent, so the compensation for the two instantaneous reactive powers leads to control the two components of the current space vector. With the theory, the neutral current of a three-phase four-wire system can be eliminated by only compensating the instantaneous reactive power using no energy storge element.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2481-2483
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• 1999

This paper proposed the p-q-r coordinate system where the instantaneous active power p, and the two instantaneous reactive powers $q_{q}$, $q_{r}$ were defined. The three power components are linearly independent, so the compensation for the two instantaneous reactive powers leads to control the two components of the current space vector. With the theory, the neutral current of a three-phase four-wire system can be eliminated by only compensating the instantaneous reactive power using no energy storage element.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.131-133
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• 1998

This paper, proposed the p-q-r coordinate system where the instantaneous active power p, and the two instantaneous reactive powers $q_{q}$, $q_{r}$ were defined. The three power components are linearly independent, so the compensation for the two instantaneous reactive powers leads to control the two components of the current space vector. With the theory, the neutral current of the three-phase four-wire system can be eliminated by only compensating the instantaneous reactive power using no energy storage element.

• Korean Journal of Applied Biomechanics
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• v.20 no.2
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• pp.117-127
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• 2010

The axes of upper forearm coordinate system have been considered as principal axis of each segment which was component of elbow joint. The purpose of this study was to verify whether the mean direction(principal axis) of instantaneous axes of rotation for pure flexion/extension motion coincided with the flexion/extension axis of upper forearm coordinate system. The same procedure was done for pronation/supination motion. Furthermore, it was tested indirectly that there was an interaction effect between the two rotational motions. The results showed that most segment coordinate axes statistically were not consistent with the mean directions of flexion/extension and pronation/supination axes of rotation. From the results, it would be concluded that the ISB coordinate systems was proved to be a little valid for human movement analysis. There also was an effect of pronation/supination angles on flexion/extension motion.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.7
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• pp.679-685
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• 2006

In this paper, development of an omni-directional mobile robot with rocker-bogie link structure is addressed. The overall mobile robot system consists of the robot mechanism with embedded control architecture, wireless communication with host graphic monitoring system, and the joy stick tole-controller. In the cluttered environment with various sizes of obstacles, the omni-directionality and the traversality are required for a mobile robot, so that the robot call go around or climb over the obstacles according to the size. The mobile robot mechanism developed in this paper has both of the omni-directionality and the traversality by 4 steerable driving wheels and the 2 additional passive omni-directional wheels linked with the rocker-bogie structure. The kinematic modeling for the mobile robot is described based on the well-known Sheth-Uicker convention and the instantaneous coordinate system.

• Journal of the Korean Society of Industry Convergence
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• v.21 no.6
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• pp.361-368
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• 2018

This paper proposes a grid - connected CTTS system that can be soft switched to meet the government's effective resource allocation policy for emergency generator. In order to eliminate the system instability caused by the large inrush current generation in the system switching, a new virtual rotation coordinate method for the dissimilar power source is proposed. The proposed virtual rotation coordinate method improves the voltage detection accuracy of the voltage difference of the dissimilar power supply, and it is proved that the synchronous switching characteristic is excellent. In addition, zero current and system stabilization can be achieved by realizing zero current when blocking CTTS with instantaneous reactive power control. Simulation was carried out to verify the validity of the proposed method, and the 500[kVA] system was fabricated and verified to demonstrate the superiority of the proposed method.

• Current Optics and Photonics
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• v.8 no.3
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• pp.300-306
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• 2024

To solve the nozzle swing angle non-contact measurement problem, we present a nozzle pose estimation algorithm involving weighted measurement uncertainty based on rotation parameters. Firstly, the instantaneous axis of the rocket nozzle is constructed and used to model the pivot point and the nozzle coordinate system. Then, the rotation matrix and translation vector are parameterized by Cayley-Gibbs-Rodriguez parameters, and the novel object space collinearity error equation involving weighted measurement uncertainty of feature points is constructed. The nozzle pose is obtained at this step by the Gröbner basis method. Finally, the swing angle is calculated based on the conversion relationship between the nozzle static coordinate system and the nozzle dynamic coordinate system. Experimental results prove the high accuracy and robustness of the proposed method. In the space of 1.5 m × 1.5 m × 1.5 m, the maximum angle error of nozzle swing is 0.103°.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.161-175
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• 1991

To understand the biomechanics of the mandibular movement of the patients with T.M.J. disorder, it is necessary to analyze the mandibular movement by the least moving points of instantaneous center of rotation on computer screen. In this study, two subjects without T.M.J. disorder and with normal occlusion and few patients with T.M.J. disorder were selected for obtaining the processing data. The habitual opening and dosing movements were recorded by image recognition system of video and computer and then the mandibular movement and the least moving point were analyzed using computer program for image anaysis of specialized points. The results obtained were as follows: 1. The least moving points of control group during opening and dosing were dose to the mandibular foramen, but in the test group there were differences between two positions of the least moving points during opening and closing. 2. The variations of the least moving point were in the range of $0.02\sim0.05cm$ of X-coordinate and $0.07\sim0.10cm$ of Y-coordinate for control group, whereas in the range of $0.05\sim0.30cm$ of X-coordinate and $0.08\sim1.65cm$ of Y-coordinate for test group. 3. The index of variation during opening and dosing movements was shown in $0.8\sim1.0$ for the control group and in $0.56\sim2.6$ for the test group. 4. After the treatment of the test group No. 4 by occlusal splint the least moving point was dose to the mandibular foramen and the index of variation was changed from 25 to 05. 5. The tracing shape of the least moving point in the test group represented the irregularities compared to the control group. 6. The mandibular opening and dosing movements were simulated on the computer screen following the movement of the least moving point of instantaneous center of rotation.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.19-22
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• 2002

A process of 3-D particle image velocimetry, called here, as '3-D stereo PIV' was developed for the measurement of a section field of 3-D complex flows. The present method includes modeling of camera by a calibrator based on the homogeneous coordinate system, transfromation of oblique-angled image to transformed image, identification of 2-D velocity vectors by 2-D cross-correlation equation, stereo matching of 2-D velocity vectors of two cameras, accurate calculation of 3-D velocity vectors by homogeneous coordinate system and finally 3-D animation as the post processing. In principle, as two frame images only are necessary for the single instantaneous analysis of a section field of 3-D flow, more effective vectors are obtainable contrary to the previous multi-frame vector algorithm. An experimental system was also used for the application of the proposed method. Three analog CCD cameras and an Argon-Ion Laser(300mW) for illumination were adopted to capture the wake flow behind a bluff obstacle.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.752-755
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• 2000

This paper describes a new algorithm for active power filters which can be control source current symmetrically under unbalanced condition in power system. Positive sequency voltage is detected by symmetrical coordinate method and compensating reference current of active power filters is calculated using by accurate phase angle information of positive sequency voltage. The basic principle of the proposed method is described in detail and the conventional and proposed phase detecting methods are compared and discussed through the simulation results.