• Journal of the Korean Institute of Intelligent Systems
• /
• v.20 no.1
• /
• pp.60-65
• /
• 2010

This paper describes the results of 2D mapping, feature detection and matching to create the surrounding environment in the mounted stereo camera on Mobile robot. Extract method of image's feature in real-time processing for quick operation uses the edge detection and Sum of Absolute Difference(SAD), stereo matching technique can be obtained through the correlation coefficient. To estimate the location of a mobile robot using ZigBee beacon and encoders mounted on the robot is estimated by Kalman filter. In addition, the merged gyro scope to measure compass is possible to generate map during mobile robot is moving. The Simultaneous Localization and Mapping (SLAM) of mobile robot technology with an intelligent robot can be applied efficiently in human life would be based.

• The Journal of the Acoustical Society of Korea
• /
• v.32 no.6
• /
• pp.541-547
• /
• 2013

The speech quality of multi-party audio telephony between two, three or more participants is decreased by audio volume imbalance, audio volume saturation and noise level increase. To solve this issue, this paper proposes an advanced audio mixing algorithm for software-based multi-point control unit. Our approach is based on the combined voice activity detection and gain control technique that consists of a set of algorithms that classify audio signals, estimate audio volumes, adjust gain factors and mix audio signals of all channels. The proposed audio mixing algorithm is computationally efficient, delivers high-quality speech, and is suitable for use in any practical multi-party audio telephony.

• Journal of Korea Multimedia Society
• /
• v.15 no.8
• /
• pp.986-995
• /
• 2012

In this paper we propose a real-time moving object tracking method on a smart phone camera. By considering the limit of non-learning approach on low-performance platforms, we use the sliding-window detection technique based on histogram features. We solve the problem of the time-consuming histogram computation on each sub-window by adapting the integral histogram. For additional speed and tracking performance, we propose a new adaptive bin method. From the experiments on our dataset, we achieved high speed performance demonstrating 34~63 frames per second.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.5
• /
• pp.986-994
• /
• 2005

This Paper proposes the likelihood-based nonlinear dimension reduction method of the speech feature parameters in order to construct the voice activity detecter adaptable in noisy environment. The proposed method uses the nonlinear values of the Gaussian probability density function with the new parameters for the speec/nonspeech class. We adapted Likelihood Ratio Test to find speech part and compared its performance with that of Linear Discriminant Analysis technique. In experiments we found that the proposed method has the similar results to that of Gaussian Mixture Models.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.2C
• /
• pp.184-190
• /
• 2006

In this paper, we propose the blind multiuser detector which is robust against the effects of near-far and multiuser interference. The proposed detector is composed of the partial IC(interference canceller) and the blind MOE(minimum output energy) multiuser detector. The partial IC partially eliminates interference components from the received signal then the output of partial IC is fed into the input of multiuser detector. Simulation results show that the proposed detector has the robust property but the performance of conventional MOE multiuser detector is rapidly degraded in case of existing both near far and multiuser. Thus, the proposed partial IC BMUD(blind multiuser detection) technique has better performance than the conventional MOE.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.1C
• /
• pp.96-102
• /
• 2002

Current testing(Iddq testing) on monitoring the quiescent power supply current is an efficient and effective method for CMOS bridging faults. The applicability of this technique, however, requires careful examination. Since cardinality of bridging fault is O($n^2$) and current testing requires much longer testing time than voltage testing, it is important to note that a bridging fault is untestable if the two bridged nodes have the same logic values at all times. Such faults should be identified by a good ATPG tool; otherwise, the fault coverage can become skewed. In this paper, we present an object-oriented redundant fault detection scheme for efficient current testing. Experimental results for ISCAS benchmark circuits show that the improved method is more effective than the previous ones.

• Journal of Information Processing Systems
• /
• v.9 no.3
• /
• pp.405-424
• /
• 2013

This research paper proposes a secured, robust approach of information security using steganography. It presents two component based LSB (Least Significant Bit) steganography methods for embedding secret data in the least significant bits of blue components and partial green components of random pixel locations in the edges of images. An adaptive LSB based steganography is proposed for embedding data based on the data available in MSB's (Most Significant Bits) of red, green, and blue components of randomly selected pixels across smooth areas. A hybrid feature detection filter is also proposed that performs better to predict edge areas even in noisy conditions. AES (Advanced Encryption Standard) and random pixel embedding is incorporated to provide two-tier security. The experimental results of the proposed approach are better in terms of PSNR and capacity. The comparison analysis of output results with other existing techniques is giving the proposed approach an edge over others. It has been thoroughly tested for various steganalysis attacks like visual analysis, histogram analysis, chi-square, and RS analysis and could sustain all these attacks very well.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.6
• /
• pp.459-463
• /
• 2009

Background modeling and motion detection is the one of the most significant real time video processing technique. Until now, many researches are conducted into the topic but it still needs much time for robustness. It is more important when other algorithms are used together such as object tracking, classification or behavior understanding. In this paper, we propose efficient multi-modal background modeling methods which can be understood as simplified learning method of Gaussian mixture model. We present its validity using numerical methods and experimentally show detecting performance.

• Journal of Sensor Science and Technology
• /
• v.11 no.4
• /
• pp.200-208
• /
• 2002

This paper represents the development of an array-type flexible tactile sensor using PVDF(polyvinylidene fluoride) film and flexible circuitry. The tactile sensor which has $8{\times}8$ taxels is made by using PVDF film and FPC(flexible printed circuit) technique. Experimental results on static and dynamic properties are obtained by applying arbitrary forces and frequencies generated by the shaker. In the static characteristics, the threshold and the linearity of the sensor are investigated. Also dynamic response of the sensor subjected to the variable frequencies is examined. The signals of a contact force to the tactile sensor are sensed and processed in the DSP system in which the signals are digitalized and filtered. Finally, the signals are integrated for taking the force profile. The processed signals of the outputs of the sensor are visualized on a personal computer, the shape and force distribution of the contacted object are obtained using two and three-dimensional image in real time. The reasonable performance for the detection of contact state is verified through the experiment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2011.04a
• /
• pp.224-229
• /
• 2011

In this paper, in order to improve safety of hybrid electric vehicle a fault detection algorithm is introduced. The proposed algorithm uses SVDD techniques. Two methods for learning a lot of data are used in this technique. One method is to learn the data incrementally. Another method is to remove the data that does not affect the next learning. Using lines connecting support vectors selection of removing data is made. Using this method, lot of computation time and storage can be saved while learning many data. A battery data of commercial hybrid electrical vehicle is used in this study. In the study fault boundary via SVDD is described and relevant algorithm for virtual fault data is verified. It takes some time to generate fault boundary, nevertheless once the boundary is given, fault diagnosis can be conducted in real time basis.