• Journal of Satellite, Information and Communications
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• v.5 no.1
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• pp.75-79
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• 2010

Satellite structure is distorted by thermal load in orbit. The structural distortion induces the pointing errors of observation unit that is difference between initial pointing direction at ground integration and at in-orbit. In that case, satellite is not able to point along required direction. As observation capability becomes higher, structural distortion due to thermal load should be smaller to achieve successful mission. In this paper, the method to predict pointing error and results are described.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.3
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• pp.145-150
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• 2011

In this study, we assessed the performance of the test remote pointing device that is applicable to interactive TV (iTV). An empirical test was carried out with the pointing devices in three different interface methods that are recently tried in the industry. For the measurement, a directional task was performed on the linear track described in the conventional ISO 9241-Part 9. The measured variables included the movement time, accuracy, throughput and the subjective satisfaction. The result showed that the motion time was better in the device in the GyroPoint method than the other devices, but the accuracy of the GyroPoint device was lower than that of the devices in the Hall Mouse and OFN methods. It was found that the throughput and the subjective satisfaction were dependent upon the individual input devices. Since this study was conducted on the major point devices that are currently tried and analyzed the problems and characteristics, it is assumed that this study will provide useful data for the design of the remote pointing device that is more suitable to the iTV environment.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.445-458
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• 2008

Image chain analysis of synthetic aperture radar (SAR) satellite is one of the primary activities for satellite design because SAR image quality depends on spacecraft bus performance as well as SAR payload. Especially, satellite pointing and stability error make worst effect on the original SAR image quality which is implemented by SAR payload design. In this research, Image chain analysis S/W was developed in order to analyze the SAR image quality degradation due to satellite pointing and stability error. This S/W consists of orbit model, attitude control model, SAR payload model, clutter model, and SAR processor. SAR raw data, which includes total 25 point targets in the scene of $5km{\times}5km$ swath width, was generated and then processed for analysis. High resolution mode (spotlight), of which resolution is 1m, was applied. The results of image chain analysis show that radiometric accuracy is the most degraded due to the pointing error. Therefore, the successful design of attitude control subsystem in spacecraft bus for enhancing the pointing accuracy is most important for image quality.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.2
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• pp.29-36
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• 2008

In this paper we propose a real-time method to estimate a pointing region from two camera images. In general, a pointing target exists in the face direction when a human points to something. Therefore, we regard the direction of pointing as the straight line that connects the face position with the fingertip position. First, the method extracts two points in the face and the fingertips region by using detecting the skin color of human being. And we used the 3D geometric information to obtain a pointing detection and its region. In order to evaluate the performance, we have build up an ICIGS(Interactive Cinema Information Guiding System) with two camera and a beam project.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.12
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• pp.1412-1422
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• 2010

A bistatic radar using the pulse chasing can detect a target to track successive transmitted pulses using a receive beam for effectively scanning the cosite search area. When tracking a transmitted pulse with the receive beam, some beam pointing errors within pulse-to-pulse can cause the timing error in received pulse and the variation of the signal strength. In this paper, we have proposed that some errors due to the receive beam pointing error could limit the MTI filter's performance and derived that the relationship between the MTI performance and the geometric factors which are the inherent properties in bistatic configuration. Through the simulation, we have considered the limitations of the improvement performance restricted by the receiving beam pointing error and confirmed the contribution to the performance improvement in maintaining the receiving beam pointing error of under 0.5 degrees.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.11
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• pp.953-960
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• 2021

Korea Astronomy and Space Science Institute has been verifying the multipurpose laser tracking system with three functions of satellite laser tracking, adaptive optics and space debris laser tracking for not only scientific research but also national space missions. The system employs an optical telescope consisting of a 100 cm primary mirror and an altazimuth mount for fast and precise tracking. The precise pointing and tracking capability in a tracking mount is considered as one of important performance metrics in the fields of automatic tracking and precise application research. So it is required to analyze a mount model for investigating pointing error factors and compensating pointing error. In this study, we investigated various factors causing static pointing errors of tracking mount and analyzed the pointing accuracy of the tracking mount at Geochang observatory by estimating mount parameters based on the least square method.

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.05a
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• pp.52-53
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• 2005

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.1
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• pp.9-16
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• 2000

In these days, the interior interface design for vehicle drivers was recognized as important affairs. Thereby, many studies are being performed for this. These studies emphasize the physical factors and usability of human, but those for the cognitive factors are not enough. Cognitive factors are very important elements to determine the drivers' performance. In this study, it was studied about the method to extract a driver's cognitive map on IP(Instrument Panel) in dynamic situation, and BPM(Blind-Pointing Method) was proposed for this. The BPM is the method to extract a cognitive map by subject's pointing action under the blinded condition. The experiment was conducted to validate compatibility of BPM as the method to extract a cognitive map. In the experiment, subjects were divided in two groups, the first group of subjects has their own vehicle and driver license, and the second group of subjects doesn't have own vehicle but has driver license. The result shows that the IP form of cognitive map is not different between two groups, and BPM is the compatible method to extract a cognitive map.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.2
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• pp.62-70
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• 2007

The aiming ability is a to improve accuracy performance of the firing vehicle. This paper describes the detection method of chatter vibration using disturbance acceleration in the pointing structure. In order to analysis vibration trends of the pointing system occurred during vehicle drive, acceleration data was processed by using data processing algorithm with moving average and Hilbert transform. Specific mode constants of acceleration were obtained under various disturbances. Vehicle velocity, road condition, property of pointing structure were considered as factors which make change of vibration trend in vehicle dynamics. Finally, back propagation neural networks have been applied to the pattern recognition for the classification of vibration signal in various driving conditions. Results of signal processing were compared and analysed.

• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.484-486
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• 1998

In this paper, a new method for controlling the pointing device on digital display using EOG(electrooculogram) which is generated from eye movement, was suggested. The manufactured system is consisting of pre-amplifier, A/D converter, serial transmission device and PC program. The EOG is amplified by pre-amplifier. And the amplified EOG is digitized and transmitted to personal computer via rs-232c by PIC16C74A. Finally, the software for controlling the pointer on digital display is developed on computer. As the result, the error between the real subject's viewing point and the point indicated by the developed pointing device on digital display was investigated into the average value, 0.72 degree for horizontal axis, 0.96 degree for vertical axis. The pointing device developed in this study is controlled by subject's eye movement, that is, the user's intention. Furthermore, the algorithm of this study is applicable for many field such as a new method remote control, a new wheelchair control and so forth.