• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.4
• /
• pp.98-106
• /
• 2011

Since prediction processes such as motion estimation motion compensation are not at the WZ video encoder but at its decoder, WZ video compression cannot have better performance than that of conventional video encoder. In order to implement the prediction process with low complexity at the encoder, WZ residual coding was proposed. Instead of original WZ frames, WZ residual coding encodes the residual signal between key frames and WZ frames. Although the proposed WZ residual coding has good performance in pixel domain, it does not have any improvements in transform domain compared to transform domain WZ coding. The WZ residual coding in transform domain is difficult to have better performance, because pre-defined quantization matrices in WZ coding are not compatible with WZ residual coding. In this paper, we propose a new quantization method modifying quantization matrix and quantization step size adaptively for transform domain WZ residual coding. Experimental result shows 22% gain in BDBR and 1.2dB gain in BDPSNR.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2005.05a
• /
• pp.421-425
• /
• 2005

A distributed FBG temperature sensor system was constructed for the use in protection of electric power system. A F-P wavelength tunable filter is used converting temperature-induced wavelength variations to temporal peak locations. We used Gaussian line-fitted algorithm to alleviate the error caused by quantization and electrical noises. The experimental results showed much better accuracy than the raw peak-detection scheme.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.744-747
• /
• 1997

High performance digital computer technology enables the digital computer-based controllers to replace traditional analog controllers used for factory automations. This replacement, however, brings up the side effects caused by discrete quantization and non-real-time execution of control softwares. This paper describes the structure of real-time simulator and controller that can be used for design and verification of real-time digital controllers. The virtual machine concept adopted by real-time simulator make the proposed simulator be independent from the specific hardware platforms. The proposed system can also be used in the loosely coupled distributed environments connected through local area network using real-time message passing algorithm and virtual data table based on the shared memory mechanism.

• Journal of Institute of Control, Robotics and Systems
• /
• v.5 no.1
• /
• pp.115-121
• /
• 1999

Advanced digital computer technology enables the computer-based controllers to replace the traditional analog controllers used in factory automations. This replacement, however, brings up the side effects caused by the quantization error and non-real-time execution of control software. This paper describes the structure of real-time simulator and controller that can be used for design and verification of real-time digital controllers. The virtual machine concept adopted by the proposed real-time simulator makes the proposed simulator be independent from the specific hardware platforms. The proposed system can also be used in the loosely coupled distributed environments connected through local area network using real-time message passing algorithm and virtual data table based on the shared memory mechanism.

• Advances in nano research
• /
• v.3 no.1
• /
• pp.49-54
• /
• 2015

The structure represents symmetrical metal electrode (gate 1) - front $SiO_2$ layer - n-Si nanowire FET - buried $SiO_2$ layer - metal electrode (gate 2). At the symmetrical gate voltages high conductive regions near the gate 1 - front $SiO_2$ and gate 2 - buried $SiO_2$ interfaces correspondingly, and low conductive region in the central region of the NW are formed. Possibilities of applications of nanosize FETs at the deep inversion and depletion as a distributed capacitance are demonstrated. Capacity density is an order to ${\sim}{\mu}F/cm^2$. The charge density, it distribution and capacity value in the nanowire can be controlled by a small changes in the gate voltages. at the non-symmetrical gate voltages high conductive regions will move to corresponding interfaces and low conductive region will modulate non-symmetrically. In this case source-drain current of the FET will redistributed and change current way. This gives opportunity to investigate surface and bulk transport processes in the nanosize inversion channel.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.41 no.4
• /
• pp.113-120
• /
• 2004

In this paper, we propose an efficient feature extraction and image retrieval algorithm for content-based retrieval method. First, we extract the object using Gaussian edge detector for input image which is key frames of MPEG video and extract the object features that are location feature, distributed dimension feature and invariant moments feature. Next, we extract the characteristic color feature using the proposed HAQ(Histogram Analysis md Quantization) algorithm. Finally, we implement an retrieval of four features in sequence with the proposed matching method for query image which is a shot frame except the key frames of MPEG video. The purpose of this paper is to propose the novel content-based image retrieval algerian which retrieves the key frame in the shot boundary of MPEG video belonging to the scene requested by user. The experimental results show an efficient retrieval for 836 sample images in 10 music videos using the proposed algorithm.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.40 no.11
• /
• pp.29-36
• /
• 2003

In this paper, an efficient VLSI architecture for DCTQ module, which consists of 2D-DCT, quantization, AC/DC prediction block, scan conversion, inverse quantization and 2D-IDCT, is presented. The architecture of the module is designed to handle a macroblock data within 1064 cycles and suitable for MPEG-4 video codec handling 30 frame CIF image for both encoder and decoder simultaneously. Only single 1-D DCT/IDCT cores are used for the design instead of 2-D DCT/IDCT, respectively. 1-bit serial distributed arithmetic architecture is adopted for 1-D DCT/IDCT to reduce the hardware area in this architecture. To reduce the power consumption of DCTQ modu1e, we propose the method not to operate the DCTQ modu1e exploiting the SAE(sum of absolute error) value from motion estimation and cbp(coded block pattern). To reduce the AC/DC prediction memory size, the memory architecture and memory access method for AC/DC prediction block is proposed. As the result, the maximum utilization of hardware can be achieved, and power consumption can be minimized. The proposed design is operated on 27MHz clock. The experimental results show that the accuracy of DCT and IDCT meet the IEEE specification.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37A no.11
• /
• pp.952-960
• /
• 2012

In the distributed video coding (DVC) system, the difference between the side information and the original Wyner-Ziv frame is corrected using channel codes and the additional parity bits are requested through feedback channel if the error is not corrected. The efficient bit rate control is important to use the DVC system in the band-limited channel, such as mobile communication environments. In this paper, the constant bit rate control method in the encoder of the DVC system is proposed. The coding performance as well as the bit rate is efficiently controlled by the proposed method.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.6
• /
• pp.2949-2963
• /
• 2019

A novel distributed compress-and-forward (CF) system based on multi-relay network is presented. In this system, as the direct link between the source and destination is invalid due to some reasons, such as the limited power, special working environment, or even economic factors, relays are employed to receive analog signals and carry on distributed compressed encoding. Subsequently, the digital signals are transmitted to the destination via wireless channel. Moreover, a theoretical analysis for the system is provided by utilizing the Chief Executive Officer (CEO) theory and Shannon channel capacity theory, and the rate-distortion function as well as the connection between the transmission rate and the channel capacity are constructed. In addition, an optimal signal-to-noise ratio (SNR) -based power allocation method is proposed to maximize the quantization SNR under the limited total power. Simulation result shows that the proposed CF system outperforms the amplify-and-forward (AF) system versus the SNR performance.

• The Journal of the Acoustical Society of Korea
• /
• v.27 no.3
• /
• pp.149-153
• /
• 2008

General underwater target detection methods adopt short-time FFT for estimate target doppler. This paper proposes the efficient target detection method, instead of conventional FFT, using approximate FFT for distributed sensor network target detection, which requires lighter computations. In the proposed method, we decrease computational rate of FFT by the quantization of received signal. For validation of the proposed method, experiment result which is applied to FFT based active sonar detector and real oceanic data is presented.