• Journal of Navigation and Port Research
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• v.37 no.5
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• pp.447-452
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• 2013

Vessel traffic system uses multiple sea surveillance radars as a primary sensor to obtain maritime traffic information like as ship's position, speed, course. The systematic errors such as the range bias and the azimuth bias of the two-dimensional radar system can significantly degrade the accuracy of the radar image and target tracking information. Therefore, the systematic errors of the radar system should be corrected precisely in order to provide the accurate target information in the vessel traffic system. In this paper, it is proposed that the method compensates the range bias and the azimuth bias using AtoN information installed at VTS coverage. The radar measurement residual error model is derived from the standard error model of two-dimensional radar measurements and the position information of AtoN, and then the linear Kalman filter is designed for estimation of the systematic errors of the radar system. The proposed method is validated via Monte-Carlo runs. Also, the convergence characteristics of the designed filter and the accuracy of the systematic error estimates according to the number of AtoN information are analyzed.

• Journal of Sensor Science and Technology
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• v.13 no.1
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• pp.12-19
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• 2004

The tinnitus which is the one of the auditory disease is a phenomenon that the patients feel the sound in the ear or the head when there is no sound sources. There have been many therapies for this tinnitus so far, but it is known that the TRT (Tinnitus Retraining Therapy) is the most effective therapy. So we designed and developed the controllable white noise generator for TRT. It must be designed as small as possible for user's convenience, such as the ITE (In The Ear) type hearing aids. It used the thermal noise as the white noise source. And filter and tone control circuits are used at the end of the noise generation part to control the white noise characteristics. This link of the controllable circuits is used to change the white noise's characteristic for the various tinnitus patients' characteristic. we can confirm that the designed and implemented controllable white noise generator which is a ITE type operates properly by the experiments of filter and tone control circuit.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.457-460
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• 2005

When a hearing aid' s user is listening through telephone or cellular phone, he/she usually suffers from severe electrical magnetic interference noise. It is because hearing aids amplify voice signal as well as background noise. A telecoil, an induction coil, is a possible solution for the problem. Because a telecoil has the characteristic of high pass filter, it has some problem of resulting increased high frequency noise. For solving this problem, we can use a capacitor connected with the telecoil in parallel. According to capacitance, receiving signal quality may change. In this paper, proper capacitor values for the best sound quality are investigated by experimental work.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.382-384
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• 2005

When a hearing aid' s user is listening through telephone or cellular phone, he/she usually suffers from severe electrical magnetic interference noise. It is because hearing aids amplify voice signal as well as background noise. A telecoil, an induction coil, is a possible solution for the problem. Because a telecoil has the characteristic of high pass filter, it has some problem of resulting increased high frequency noise. For solving this problem, we can use a capacitor connected with the telecoil in parallel. According to capacitance, receiving signal quality may change. In this paper, proper capacitor values for the best sound quality are investigated by experimental work.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.551-553
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• 2005

When a hearing aid' s user is listening through telephone or cellular phone, he/she usually suffers from severe electrical magnetic interference noise. It is because hearing aids amplify voice signal as well as background noise. A telecoil, an induction coil, is a possible solution for the problem. Because a telecoil has the characteristic of high pass filter, it has some problem of resulting increased high frequency noise. For solving this problem, we can use a capacitor connected with the telecoil in parallel. According to capacitance, receiving signal quality may change. In this paper, proper capacitor values for the best sound quality are investigated by experimental work.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.133.1-133
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• 2001

When the signals from satellite vehicles are blocked, it is impossible to provide positioning information. Integrating CDGPS with INS, the performances of output can be greatly improved. In the CDGPS/INS integrated system, the error growth in INS can be efficiently suppressed due to CDGPS. On the contrary, the search range of integer ambiguities can be reduced with the aids of INS. Furthermore, cycle slips in carrier phase measurements can be easily detected using INS. The paper presents a CDGPS/INS integrated system that utilizes CDGPS aided with INS. Using the outputs of CDGPS/INS integration filter, a method to reduce search range of integer ambiguities is proposed. A method to detect cycle slips in carrier phase measurements is ...

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.389-389
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• 2000

The number of automobiles is rapidly increasing , as are the importance of the car as a way of transportation, and the variety of its uses. In these surroundings, a safety, one of the primary factors which must be considered in automotive engineering, demands a system that aids the driver's vision and perception. In this point of view, development of the more promoted system that complement the existing passive method which relies on just man's ability is the important issue of the advanced traffic system including ITS. In this paper, we provide an algorithm and implementation of a control system that warns the collisions ahead and avoids this situation, using informations about the host-car, target-car and surroundings. The warning is made by an algorithm that decides the degree of safely. With this degree of safely, the controller automatically controls a vehicle's speed to a proper level.

• Journal of Pharmaceutical Investigation
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• v.3 no.4
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• pp.39-43
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• 1973

완충액(緩衝液)에서의 caffeine, niacinamide, pyridoxine hydrochloride, thiamine hydrochloride의 여과조제(濾過助劑)에 의(依)한 흡착(吸着)현상을 비교검토(比較檢討)하였다. 실험(實驗)에 사용(使用)한 vitamin 류(類)의 흡착(吸着)은 Langmvir 흡착식(吸着式)의 pattern 에 따랐으며 caffeine 은 거의 흡착(吸着)되지 않았다. 여과조제중(濾過助劑中) Dawsonite는 Celite 545 보다 큰 흡착(吸着)현상을 나타냈으며 pH변화(變化)에 따른 영향(影響)은 niacinamide가 가장 예민하였고 pH의 증가(增加)는 흡착량(吸着量)을 현저히 감소시켰다.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.3
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• pp.319-329
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• 2016

High-level design aids are mandatory for design of a continuous-time delta-sigma modulator (CTDSM). This paper proposes a top-down methodology design to generate a noise transfer function (NTF) which is compensated for excess loop delay (ELD). This method is applicable to low pass loop-filter topologies. Non-ideal effects including ELD, integrator scaling issue, finite op-amp performance, clock jitter and DAC inaccuracies are explicitly represented in a behavioral simulation of a CTDSM. Mathematical modeling using MATLAB is supplemented with circuit-level simulation using Verilog-A blocks. Behavioral simulation and circuit-level simulation using Verilog-A blocks are used to validate our approach.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.3
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• pp.387-394
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• 2013

A travel aid system for the visually impaired person is proposed by providing the position and heading information. The position and heading information is obtained from range difference localization estimator, and the information is notified to the visually impaired person by using braille display system. For the precise estimation of the position and heading information, we apply recently developed linear localization estimator which utilizes the instrumental variable method and the state augmentation method. The estimation results are compared with well-known Kalman filter through experiment.