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Quality monitoring and biases estimation of BOC navigation signals

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Journal of Systems Engineering and Electronics 2019年第3期30卷 474-484页

作者： ZHAO Hongwei ZHANG Zichun LUO Xianzhi wang qiuping School of Electronics and Information Northwestern Polytechnical University Xi’an 710129 China State Key Laboratory of Satellite Navigation System and Equipment Technology Shijiazhuang 050081 China

Many safety-critical applications that utilize the global navigation satellite system (GNSS) demand highly accurate positioning information, as well as highly integrity and reliability. Due to GNSS signals are easily distorted by the interferences or disturbances, the signal quality monitoring (SQM) is necessary to detect the presence of dangerous signal distortions. In this paper, we developed an SQM software for binary offset carrier (BOC) modulated navigation signals. Firstly, the models of BOC signal with ideal and distortion are presented respectively. Then the architecture of SQM software is proposed. Moreover, the effect of the white gaussian noise (WGN) and the front-end filter on the correlation peak of the receiver is analyzed. Finally, the biases induced by the signal distortion are evaluated. The experiments simulate the relationships between the code phase shift and the normalized correlation value in the case of the signal digital distortion and the analog distortion. The simulation results demonstrate that the proposed SQM method can effectively monitor the signal distortion and accurately estimate the correlation peak deviation caused by the distortion.

关键词： signal quality monitoring (SQM) binary offset carrier (BOC) modulation biases estimation signal distortion correlation peak

Efficient distributed algorithms for holistic aggregation functions on random regular graphs

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Science China(Information Sciences) 2022年第5期65卷 32-50页

作者： Lin JIA Qiang-Sheng HUA Haoqiang FAN qiuping wang Hai JIN National Engineering Research Center for Big Data Technology and System/Services Computing Technology and System Lab/Cluster and Grid Computing Lab School of Computer Science and TechnologyHuazhong University of Science and Technology Institute for Interdisciplinary Information Science Tsinghua University

In this paper, we propose efficient distributed algorithms for three holistic aggregation functions on random regular graphs that are good candidates for network topology in next-generation data *** three holistic aggregation functions include SELECTION（select the k-th largest or smallest element）,DISTINCT（query the count of distinct elements）, MODE（query the most frequent element）. We design three basic techniques — Pre-order Network Partition, Pairwise-independent Random Walk, and Random Permutation Delivery, and devise the algorithms based on the techniques. The round complexity of the distributed SELECTION is Θ（log N） which meets the lower bound where N is the number of nodes and each node holds a numeric element. The round complexity of the distributed DISTINCT and MODE algorithms are O（log;N/log log N） and O（log;N log log N） respectively. All of our results break the lower bounds obtained on general graphs and our distributed algorithms are all based on the CON GE S T model, which restricts each node to send only O（log N） bits on each edge in one round under synchronous communications.

关键词： distributed algorithms holistic aggregation function random regular graph $\mathcal{CONGEST}$ model communication complexity round complexity

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Application of varentropy as a measure of probabilistic uncertainty for complex networks

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Chinese Science Bulletin 2011年第34期56卷 3677-3682页

作者： JIANG Jian wang Ru PEZERIL Michel wang qiuping Alexandre Institut Superieur des Materiaux et Mecaniques Avarices 44 Avenue F.A. Bartholdi 72000 Le Mans France Complexity Science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LPEC Faculte des Sciences et Techniques Universite du Maine Ave. O. Messiaen 72035 Le Mans France College of Information Science and Engineering Huaqiao University Quanzhou 362021 China

Varentropy is used as a general measure of probabilistic uncertainty for a complex network, inspired by the first and second laws of thermodynamics, but not limited to the equilibrium system. By exploring the relationship between the varentropy of the scale free distribution and the exponent of power laws as well as network size, we get the optimal design of a scale-free network against random failures. The behaviors of varentropy and the Shannon entropy of double Pareto law degree distribution are analyzed to compare their usefulness. Our conclusion is that varentropy is suitable and reliable.

关键词：概率不确定性网络应用 Shannon熵无标度网络第二定律平衡系统幂律指数网络规模

Variational quality control of non-Gaussian innovations and its parametric optimizations for the GRAPES m3DVAR system

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Frontiers of Earth Science 2023年第2期17卷 620-631页

作者： Jie HE Yang SHI Boyang ZHOU qiuping wang Xulin MA Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640China Guangdong Meteorological Observatory Guangzhou 510640China Qingdao Air Traffic Management Station of Civil Aviation of China Qingdao 266108China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological DisasterNanjing University of Information Science and TechnologyNanjing 210044China

The magnitude and distribution of observation innovations,which have an important impact on the analyzed accuracy,are critical variables in data *** quality control(VarQC)based on the contaminated Gaussian distribution(CGD)of observation innovations is now widely used in data assimilation,owing to the more reasonable representation of the probability density function of innovations that can sufficiently absorb observations by assigning different weights ***,the inaccurate parameters prevent VarQC from showing the advantages it should have in the GRAPES(Global/Regional Assimilation and PrEdiction System)m3DVAR ***,the parameter optimization methods are considerable critical studies to improve *** this paper,we describe two probable CGDs to include the non-Gaussian distribution of actual observation errors,Gaussian plus flat distribution and Huber norm *** potential optimization methods of the parameters are introduced in detail for different *** different parameter configurations,the optimization analysis shows that the Gaussian plus flat distribution and the Huber norm distribution are more consistent with the long-tail distribution of actual innovations compared to the Gaussian *** VarQC’s cost and gradient functions with Huber norm distribution are more reasonable,while the VarQC’s cost function with Gaussian plus flat distribution may converge on different minimums due to its nonconcave *** weight functions of two VarQCs gradually decrease with the increase of innovation but show different shapes,and the VarQC with Huber norm distribution shows more elasticity to assimilate the observations with a high contamination ***,we reveal a general derivation relationship between the CGDs and VarQCs.A novel schematic interpretation that classifies the assimilated data into three categories in VarQC is *** are conducive to the development of a new Var

关键词： data assimilation variational quality control contaminated Gaussian distribution non-Gaussian distribution innovation

English and Chinese language frequency time series analysis

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Chinese Science Bulletin 2011年第34期56卷 3717-3722页

作者： DENG WeiBing wang DuJuan LI Wei wang qiuping Alexandre LUNAM UniversitY ISMANS Laboratoire de Physique Statistique et Systemes Complexes 44 Ave. Bartholdi 72000 Le Mans France Complexity Science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LUNAM UniversitY Universite du Maine LPEC UMR CNRS 6087 72085 Le Mans France Max-Planck-lnstitutefor Mathematics in the Sciences Leipzig 04103 Germany

English and Chinese language frequency time series (LFTS) were constructed based on an English and two Chinese novels. Methods of statistical hypothesis testing were adopted to test the nonlinear properties of the LFTS. Results suggest the series exhibited non-normal, auto-correlative, and stationary characteristics. Moreover, we found that LFTS follow the power law distributions, and thereby we investigated the fractal structure, long range correlation, and intermittency, which indicated the self-similarity features of LFTS, and also provided hints that human societies are likely to share some universal properties.

关键词：时间序列分析频率语言中文英文统计假设检验非线性特性长程相关性

Investigation of an energy nonadditivity for nonextensive systems

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Chinese Science Bulletin 2011年第34期56卷 3661-3665页

作者： wang Ru NGANSO DJANTENG Sandrine KAABOUCHI EI Aziz wang qiuping Alexandre Institut Supdieur des Materiaux du Mans 44 Avenue F. A. Bartholdi Le Mans 72000 France College of Information Science and Engineering Huaqiao University Quanzhou 362021 China LPEC UMR CNRS 6087 Universite du Maine Av. O. Messiaen Le Mans 72085 France

We investigate the energy nonadditivity relationship E(AαB) = E(A) + E(B) + αE(A)E(B) which is often considered in the development of the statistical physics of nonextensive systems. It was recently found that α in this equation was not constant for a given system in a given situation and could not characterize nonextensivity for that system. In this work, we select several typical nonextensive systems and compute the behavior of α when a system changes its size or is divided into subsystems in different fashions. Three kinds of interactions are considered. It is found by a thought experiment that α depends on the system size and the interaction as expected and on the way we divide the system. However, one of the major results of this work is that, for given system, α has a minimum with respect to division position. Around this position, there is a zone in which α is more or less constant, a situation where the sizes of the subsystems are comparable. The width of this zone depends on the interaction and on the system size. We conclude that if α is considered approximately constant in this zone, the two mathematical difficulties raised in previous studies are solved, meaning that the nonadditive relationship can characterize the nonadditivity of the system as an approximation. In all the cases, α tends to zero in the thermodynamic limit (N→∞) as expected.

关键词：子系统能源统计物理学热力学极限相互作用思想实验近似系统等式

Polystyrene nanoplastics aggravated ecotoxicological effects of polychlorinated biphenyls in on zebrafish(Danio rerio)embryos

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Geoscience Frontiers 2022年第3期13卷 168-176页

作者： Yizheng Li Shulin Liu qiuping wang Yanling Zhang Xikun Chen Lei Yan Muhammad Junaid Jun wang College of Marine Sciences South China Agricultural UniversityGuangzhou 510642China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 528478China Institute of Eco-Environmental Research Guangxi Academy of SciencesNanning 530007China

In view of the accumulation of nanoplastics(NPs)in the food chain of environment and animals,and the good adsorption properties of nano-plastics to toxic substances,it is necessary to explore the influence of NPs in living *** this study,single and joint toxicological effects of polystyrene nanoplastics(PS-NPs,size 80 nm)and polychlorinated biphenyls(PCBs),were explored in freshwater aquatic animal model zebrafish(Danio rerio).Our study found that exposure to single PS-NPs induced mild acute toxicity,albeit the combined exposure of PS-NPs and polychlorinated biphenyls aggravated the toxicity of PCBs in a dose-dependent *** from gene expression profiling showed that NPs exposure could activate detoxification process,resulting in a slight up-regulation of antioxidant genes(sod1,gstp1),bone development genes(bmp2,bmp4)and cardiac gene(tbx20);while PCBs suppressed the detoxification through down-regulation of these genes,and the addition of NPs will exacerbate the impact of PCBs on gene ***,the results of in vivo purification experiments found that NPs showed prolonged retention in liver,intestine and gills of zebrafish and they might have crossed biological barrier and accumulate in lipid-rich tissues and excretion does not appear as the significant pathway for their *** conclusion,the toxic effects of polychlorinated biphenyls on chorionic protected embryos were not significant as zebrafish chorion plays an important role in resisting the invasion of pollutants;PCBs can seriously damage the bone and heart development of zebrafish,while the presence of NPs significantly enhanced the toxicity of PCBs in zebrafish,which is an alarming concern for growing NPs levels and ecological safety in aquatic environment.

关键词： Nanoplastics Zebrafish embryos Polychlorinated biphenyls(PCBs) Joint toxicity Gene expression

Structure and collaboration relationship analysis in a scientific collaboration network

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Chinese Science Bulletin 2011年第34期56卷 3702-3706页

作者： HUI Zi CAI Xu GRENECHE Jean-Marc wang qiuping Alexandre LUNAM Universite ISMANS 44 Ave. Bartholdi 72000 Le Mans France Complexity Science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LUNAM Universite Universite du Maine LPEC UMR CNRS 6087 72085 Le Mans France

We construct a weighted network of scientific collaboration in computational geometry and study the statistical properties of the network. In addition, we introduce a parameter called the collaboration relationship parameter to measure the collaboration between scientists. The collaboration relationship parameter of two scientists depends not only on the connection weights between the nodes, but also on the network's structure. The stability of the network's structure in terms of different edge removal strategies is also studied. According to the parameter, we find that a community structure exists in this type of network.

关键词：合作网络社会结构科学家协作关系合作关系计算几何统计特性参数调用

The uncertainty measure for q-exponential distribution function

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Chinese Science Bulletin 2013年第13期58卷 1524-1528页

作者： OU CongJie EL KAABOUCHI Aziz wang qiuping Alexandre CHEN JinCan College of Information Science and Engineering Huaqiao University Institut Supérieur des Matériaux et Mécaniques Avancés du Mans 44Avenue F.A. Bartholdi72000 Le MansFrance Department of Physics Xiamen University

Based on the q-exponential distribution which has been observed in more and more physical systems, the uncertainty measure of such an abnormal distribution can be derived by employing a variational relationship which can be traced from the first and second thermodynamic laws. The uncertainty measure obtained here can be considered as the entropic form for the abnormal physical systems having observable q-exponential distribution. This entropy will tend to the Boltzmann-Gibbs entropy when the nonextensive parameter tends to unity. It is very important to find that this entropic form is always concave and the systemic entropy is maximizable.

关键词：不确定性度量分布函数不确定性测度指数分布物理系统异常分布热力学定律吉布斯