Applied Mechanics and Materials Vols. 263-266

Abstract: We implemented parallel processing of polar-orbiting meteorological satellite MERSI data aerosol retrieval program. The parallel implementation was based on Linux cluster architecture. The master-slave parallel programming mode on MPI parallel environment was applied. Performance optimizations are made in load balance, communication overhead, storage and system I/O according to the specific environment. In addition, parallel speed-up ratio and efficiency were analyzed to evaluate the experiment results. Experimental results demonstrate that the parallel techniques and the performance optimization methods proposed here can significantly improve the efficiency of satellite mass-data processing program.

Abstract: After a deep investigation on the performance measure of the video conference and the video quality assessment methods, the whole plan of video quality assessment (VQA) for video conference system is proposed. Without reference video source, a novel No-Reference (NR) VQA method based on both the coding layer information and the packet layer transmission performance is introduced. The experimental result shows that the proposed method can obtain the dependable score which close to the subjective assessment.

Abstract: Taking into account that the Surfacelet hard threshold video de-noising would produce pseudo-Gibbs phenomenon, this paper proposes Surfacelet transform video de-noising method combining Cycle Spinning. Experimental results show that video which is processed by this algorithm not only eliminates the pseudo-Gibbs phenomenon which is produced by hard threshold de-noising, but also achieves higher PSNR, significantly improving the video quality after de-noising.

Abstract: Data capture system gathers network packets, documents and operation records generated in training and experimental process of information system, which provides data support for the simulation of the information systems, analysis and experimental evaluation. This paper first analyzes and compares existing data acquisition technologies, then proposes a data acquisition technique using API intercepted, the dynamic library hijacked and database triggers. This method has the advantages of high efficiency and no packet loss, and has been successfully applied to data capture in the training of a large information system.

Abstract: Based on the semidefinite programming relaxation of the design of FIR digital filters with SP2 coefficients, a feasible direction method is presented. Coupled with a randomized method, and a suboptimal solution is obtained for the problem. Furthermore, its convergence result is given. Simulation results demonstrate that the feasible direction method is an efficient method.

Abstract: Video quality assessment can be gotten by combination the distortion in the space area and the time area. As we all known that edge information is one of the most important features in image quality estimation. Based on the edge model in the perceived image quality estimation, we used it in the space and time area in the video, and get the edge information distorted model in space area and time area of the video. Using multilinear regression to combine the two models, we can get the video quality assessment model based on edge information. The proposed model only uses the edge information, and the consumption in both areas is small. After compared with other methods given by video quality estimation group, it’s found that our method is convenient and good at the 50 Hz video sequence of low bit rate(768kb/s -4.5 Mb/s).

Abstract: The performance of singular value decomposition (SVD) based nonlocal mean (NLM) denoising method degrades when the noise is high. This paper describes an approach of an improvement of NLM denoising when the noise is large. Instead of SVD, we combine the kernel principal component analysis (KPCA) with NLM. It is demonstrated in terms of peak signal to noise ratio (PSNR) in decibels (dB) that the NLM denoising method is improved using various test images corrupted by large additive white Gaussian noise (AWGN)

Abstract: To reduce the redundancy, a new integrated wavelet-based surfacelet transform(WBST) is proposed. The integrated WBST is constructed by combining the integrated 3D non-redundant wavelet with nonsubsampled directional filter banks. For 3D non-redundant wavelet transform, there are seven high frequency sub-bands and one high frequency sub-bands. Therefore, we design the integrated scheme with three high frequency sub-bands. In order to get the texture-spatial features, 3D local binary pattern (3D LBP) is used to describe the dynamic texture feature of low frequency sub-band. The mean and standard deviation of coefficients in each sub bands can be used as the high frequency features. Experiments show that the proposed algorithm using the integrated WBST outperforms the 3D WT.

Abstract: With the emergence of large-volume and high-speed streaming data, traditional techniques for mining closed frequent itemsets has become inefficient. Online mining of closed frequent itemsets over streaming data is one of the most important issues in mining data streams. In this paper, a combinative data structure is designed by using an effective bit-victor to represent items and an extended dictionary frequent item list to record the current closed frequent information in streams. For tremendous reduction of search space, some new search strategies are proposed to avoid a large number of intermediate itemsets generated. Meanwhile, some new pruning strategies are also proposed for the purpose of efficiently and dynamically maintaining of all the closure check operations. Experimental results show that the method proposed is efficient in time, with sound scalability as the number of transactions processed increases and adapts rapidly to the changes in data streams.

Abstract: This article describes a measurement of human abdominal fat device designed based on BIS (bioimpedance spectroscopy), the device adopts four electrodes multi-frequency bioelectrical impedance measurement system, including the programmable signal generator module and the amplitude and phase detection module. Program controlled signal generator module can generate the high output impedance of the constant current source in the eight frequency points constant current source between 5KHz and1MHz; amplitude phase detecting module can detect the human body electrical impedance real part and imaginary part information. Therefore, the device can be accurate measurement of human abdominal impedance information in the whole frequency range. Meanwhile, according to the selected electrode fixed position and the appropriate measurement scheme, can calculate the corresponding depth of abdominal fat content.