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2014 International Conference on Computer,Communications and information Technology(CCIT 2014)

作者： Ming Li Haiping Wei Liping Xiao Zhiyong Suo Beijing Aerospace Automatic Control Institute National Key Laboratory of Science and Technology on Aerospace Intelligent Control National Lab.of Radar Signal Processing Xidian Univ.

ISBN: (纸本)9781629939865

A fast multi-baseline Interferometric synthetic aperture radar(In SAR) phase ambiguity resolving method is presented. The ambiguity solution vector of the shortest baseline is first computed and used as a reference, and then the ambiguity solutions of all the other baselines are selected with logical judgment of phase difference between the measured phase and the wrapped phase, which is obtained by rewrapping the product of the referenced phase and the ratios of the other baselines to the referenced baseline. 1-dimensional searching is then executed on the same index of the reserved ambiguity solutions vectors. Furthermore, the wrong estimates affected by noise are eliminated by taking the largest frequency of the ambiguity numbers counted in a window. Compared to the conventional Chinese remainder theory(CRT), the proposed method is more robust and has much less computational complexity. The validity is investigated with simulated results.

关键词： multi-baseline interferometric synthetic aperture radar(In SAR),phase ambiguity resolving,Chinese remainder theory(CRT)

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Remote sensing identification of shrub encroachment in grassland in Inner Mongolia

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Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 2014年第11期30卷 152-158页

作者： Dong, Zhou Zhao, Xia Liang, Dong Huang, Wenjiang Peng, Dailiang Huang, Linsheng Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education Anhui University Hefei 230039 China School of Electronic and Information Engineering Anhui University Hefei 230039 China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100094 China State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Shrub encroachment has been a wide phenomenon across the arid and semi-arid grasslands in Inner Mongolia, China. Although numerous studies have investigated the effect of this phenomenon on community composition, ecosystem structure, and nutrient cycling, reports on the distribution patterns of shrub encroachment are limited. A recent development in satellite remote sensing enables accurate assessment of shrub distribution and its dynamics at large scales. In this paper, the combined ground survey in Xianghuangqi, four satellite images (with spatial resolution of 5.8 m) of ZY-3, covering nearly the whole area and taken between July and August in 2013, were used to identify the shrub distribution in this region. It should be noted that the shrub here indicated the shrub-grass mosaic due to the mixed pixel effect, and the identification was weak when the coverage of shrub was on low levels. The NDVI threshold method was first used to extract the vegetation coverage area, and then three traditional pixel-oriented methods (Support vector machine, Maximum likelihood and Mahalanobis distance), compared with the object-oriented method, were used for the classification of images. Object-oriented method is different from the traditional one, in that the classification is not based on the spectral characteristics of individual pixel, but relies on the image object with spatial texture and shape and size characteristics. Ground survey data were used to compare the accuracy level of these methods. It indicated that the shrub recognition accuracy by using support vector machine algorithm is the highest among the three pixel-oriented methods, with higher producer accuracy and user accuracy than the other two algorithms. Furthermore, the overall classification accuracy of this algorithm is 81.15% higher than that of the maximum likelihood (73.33%) and the Mahalanobis distance (61.77%). However, the overall recognition accuracy by using the object-oriented approach (combined scale

关键词： Maximum likelihood

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High-accuracy ultrasonic positioning through optimization of the extended Kalman filter algorithm

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Computer Modelling and New Technologies 2014年第12期18卷 277-283页

作者： JunZheng, Li Da, Yuan Bin, Wang School of Information Science and Engineering Shandong Normal University Jinan China Key Laboratory of Intelligent Information Processing in Universities of Shandong Shandong Institute of Business and Technology Yantai China

The application of extended Kalman filter algorithm to ultrasonic positioning systems has difficulty in meeting the requirements of precision positioning because the algorithm produces a new calculation error when the system is linearized. Modal optimization of the extended Kalman filter algorithm is thus investigated. The received ultrasonic signal is first decomposed by empirical mode decomposition, the intrinsic mode functions that best represent the original signal are then selected to restructure the waveform, and the transition time is finally corrected. Meanwhile, the ultrasonic wave velocity can be corrected. Traditional ultrasonic positioning can also be improved by combining with a radio-frequency module. It is experimentally shown that the proposed method limits positioning error to within ±5 cm and within ±1 cm after multiple recursions.

关键词： Intrinsic mode functions

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A recursive information gene selection using improved Laplacian Maximum Margin Criterion

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Journal of information and Computational Science 2013年第14期10卷 4435-4443页

作者： Wang, Bangyuan Xu, Hongyang Wang, Nian Bao, Wenxia Anhui Economic Management Institute Department Hefei 230059 China Key Laboratory of Intelligent Computer and Signal Processing Ministry of Education Anhui University Hefei 230039 China

Gene selection is an important research topic in pattern recognition and tumor classification. Numerous methods have been proposed, Maximum Margin Criterion (MMC) is one of the famous methods have been proposed to solve the small size samples problem. But, the MMC only considers the global structure of samples. In this article, a novel recursive gene selection criterion named Laplacian Maximum Margin Criterion Recursive Feature Elimination (LMMC-RFE) is proposed to address this issue. The Laplacian within-class scatter matrix and Laplacian between-class scatter matrix can be formulated by the use of LoG weighted matrix to capture the scatter information. The neighboring structure of the withinclass samples is preserving while the samples from different classes are mapped far from each other. The successful application to the Colon dataset, Prostate dataset and Leukemia dataset suggests this proposed method is more efficient and competitive in gene selection. 1548-7741/Copyright © 2013 Binary information Press.

关键词： Feature extraction

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Spectral power estimation for unevenly spaced motor imagery data

Spectral power estimation for unevenly spaced motor imagery ...

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20th International Conference on Neural information processing, ICONIP 2013

作者： Li, Junhua Struzik, Zbigniew Zhang, Liqing Cichocki, Andrzej MOE-Microsoft Key Laboratory for Intelligent Information and Intelligent Systems Shanghai Jiao Tong University Shanghai 200240 China Laboratory for Advanced Brain Signal Processing Brain Science Institute RIKEN Saitama 351-0198 Japan

ISBN: (纸本)9783642420535

The human brain can send a command to external devices or communicate with the outside environment by the means of a brain computer interface (BCI) system. The effectiveness depends on how precisely specific brain activities can be identified from EEG. Noise is usually mixed into the EEG signal, and cannot be separated or filtered out in some cases. In a practical BCI system, the whole segment of EEG is discarded when a portion of that segment is contaminated by extreme noise or artifacts. This leads to the weakness that the BCI system cannot output decoding results during the period of that discarded segment. In order to solve this problem, we employed a Lomb-Scargle periodogram to estimate the spectral power based on an unevenly spaced segment, a portion of which has been removed due to noise contamination. According to the classification results of motor imagery data, the accuracy is not dramatically decreased along with increased proportion of data removal. © Springer-Verlag 2013.

关键词： Brain computer interface

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A model of three points for location estimation in wireless sensor networks

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2013 2nd International Symposium on Materials Science and Engineering Technology, ISMSET 2013

作者： Xie, Shao Guo Hu, Yan Jun Wang, Yi Jiang, Fang Liu, Jing Jing Wang, Ying Guan Key Laboratory of Intelligent Computing and Signal Processing Ministry of Education AnHui University Hefei China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Road Shanghai 200050 China

ISBN: (纸本)9783037858028

In this paper, we propose a novel model of three points named TP for location estimation in wireless sensor networks (WSNs) with random deployment of anchor nodes. In this model, we select three anchor nodes which have the strongest received signal strength (RSS) for location estimation, the centroid algorithm and the method of intersection of judgment are used to estimate the location of unknown nodes. To further exploit three nearest intersection points in TP, the enhanced TP (ETP) is proposed. The simulation results show that the proposed models outperform MMSE and BML in terms of the localization accuracy for WSNs. Moreover, the localization accuracy of the proposed models in scenario 2 with random deployment of anchor nodes are better than in scenario 1 with planned deployment of anchor nodes. Additionally, compared with MMSE and BML, ETP and TP can reduce the environmental impact on location estimation. © (2013) Trans Tech Publications, Switzerland.

关键词： Location

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DOA and Doppler frequency estimation based on sub-aperture MUSIC

DOA and Doppler frequency estimation based on sub-aperture M...

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3rd IFAC Conference on intelligent Control and Automation Science, ICONS 2013

作者： Liu, Xiaoli Liao, Guisheng College of Communication Engineering Hangzhou Dianzi University Hangzhou 310018 China Zhejiang Provincial Testing Institute of Electronic and Information Products China National Laboratory of Radar Signal Processing Xidian University Xi'an China

ISBN: (纸本)9783902823458

Most available algorithms for DOA estimation in monostatic MIMO radar involve the computation of covariance matrix and its inversion or eigendecomposition, of which the computational complexity is expensive, especially in the case that both the number of sensors and snapshots are large. To solve this problem, a high-resolution algorithm for joint direction-of-arrival (DOA) and Doppler Frequency estimation based on sub-aperture MUSIC in monostatic MIMO radar is presented. Firstly, the received data matrix form each transmitter is evenly divided into four sub-blocks. Then two-dimensional fast Fourier transforms (2D-FFTs) is applied to each sub-block in order to achieve coherent integration. By utilizing the data corresponding to the peaks of coherent integration in each sub-block, a reduceddimensional data vector is constructed for joint DOA and Doppler frequency estimation via root-MUSIC. Since the full-dimensional covariance matrix estimation and eigendecomposition are avoided, the computational complexity is relatively small. Simulation results demonstrate the effectiveness of the proposed method with slightly better performance than that of ESPRIT-based method. Copyright © 2013 IFAC.

关键词： Computational complexity

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Performance analysis of irregular non-binary LDPC coded modulation over atmospheric turbulence channel

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International Journal of Applied Mathematics and Statistics 2013年第19期49卷 308-314页

作者： Li, Dashe Li, Yuan An, Zhiyong Liu, Shue School of Computer Science and Technology Shandong Institute of Business and Technology Yantai 264005 Shandong China Key Laboratory of Intelligent Information Processing in Universities of Shandong Shandong Institute of Business and Technology Yantai 264005 China School of Computer Science and Technology Binzhou Medical University Yantai 264003 Shandong China

Irregular non-binary LDPC codes have better error performance than binary ones. A channel model is established for atmospheric transmission channels under turbulence, and irregular non-binary LDPC coding and modulation systems are built based on this. Then, a stimulation platform is built and the LOG-FFT-BP algorithm is applied in hardware implementation of irregular non-binary LDPC coding. The results show that compared with binary LDPC codes, with the increase of the signal to noise ratio, the system bit error rate of non-binary ones is declined sharply and the performance is obviously improved. © 2013 by CESER Publications.

关键词： Atmospheric turbulence

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A Model of Three Points for Location Estimation in Wireless Sensor Networks

A Model of Three Points for Location Estimation in Wireless ...

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2013 2nd International Symposium on Materials Science and Engineering Technology(ISMSET 2013)

作者： Shaoguo Xie Yanjun Hu Yi Wang Fang Jiang Jingjing Liu Yingguan Wang Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education An Hui University Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences

In this paper, we propose a novel model of three points named TP for location estimation in wireless sensor networks(WSNs) with random deployment of anchor nodes. In this model, we select three anchor nodes which have the strongest received signal strength(RSS) for location estimation, the centroid algorithm and the method of intersection of judgment are used to estimate the location of unknown nodes. To further exploit three nearest intersection points in TP, the enhanced TP(ETP) is proposed. The simulation results show that the proposed models outperform MMSE and BML in terms of the localization accuracy for WSNs. Moreover, the localization accuracy of the proposed models in scenario 2 with random deployment of anchor nodes are better than in scenario 1 with planned deployment of anchor nodes. Additionally, compared with MMSE and BML, ETP and TP can reduce the environmental impact on location estimation.

关键词： Location estimation Anchor node Wireless sensor networks

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Nitrogen vertical distribution by canopy reflectance spectrum in winter wheat

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IOP Conference Series: Earth and Environmental Science 2014年第1期17卷

作者： W J Huang Q Y Yang D L Peng L S Huang D Y Zhang G J Yang Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing 100094 China Key Laboratory of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei 230039 Anhui China Beijing Agriculture Information Technology Research Center Beijing 100097 China

Nitrogen is a key factor for plant photosynthesis, ecosystem productivity and leaf respiration. Under the condition of nitrogen deficiency, the crop shows the nitrogen deficiency symptoms in the bottom leaves, while excessive nitrogen will affect the upper layer leaves first. Thus, timely measurement of vertical distribution of foliage nitrogen content is critical for growth diagnosis, crop management and reducing environmental impact. This study presents a method using bi-directional reflectance difference function (BRDF) data to invert foliage nitrogen vertical distribution. We developed upper-layer nitrogen inversion index (ULNI), middle-layer nitrogen inversion index (MLNI) and bottom-layer nitrogen inversion index (BLNI) to reflect foliage nitrogen inversion at upper layer, middle layer and bottom layer, respectively. Both ULNI and MLNI were made by the value of the ratio of Modified Chlorophyll Absorption Ration Index to the second Modified Triangular Vegetation Index (MCARI/MTVI2) referred to as canopy nitrogen inversion index (CNII) in this study at ±40° and ±50°, and at ±30° and ±40° view angles, respectively. The BLNI was composed by the value of nitrogen reflectance index (NRI) at ±20° and ±30° view angles. These results suggest that it is feasible to measure foliage nitrogen vertical-layer distribution in a large scale by remote sensing.

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