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Epidemic spreading on scale-free networks with diversity of node anti-attack abilities

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 73-76,126页

作者： song Yu-rong JIANG Guo-ping Center for Control and Intelligence Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Automation Nanjing University of Posts and Telecommunications Nanjing 210003 China

In this article, a modified susceptible-infected-removed （SIR） model is proposed to study the influence of diversity of node anti-attack abilities on the threshold of propagation in scale-free networks. In particular, a vulnerability function related to node degree is introduced into the model to describe the diversity of a node anti-attack ability. Analytical results are derived using the mean-field theory and it is observed that the diversity of anti-attack of nodes in scale-free networks can increase effectively the threshold of epidemic propagation. The simulation results agree with the analytical results. The results show that the vulnerability functions can help adopt appropriate immunization strategies.

关键词： epidemic spreading scale-free network SIR model anti-attack vulnerability function

Discrete Capability of the Lempel-Ziv Complexity Algorithm on a Vibration Sequence

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Chinese Physics Letters 2010年第6期27卷 20-23页

作者： LI Jian-Kang song Xiang-rong YIN Ke Department of Engineering Mechanics Faculty of Science Jiangsu University Zhenjiang 212013 School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003

The Lempel Ziv complexity （LZC） method is used to analyze the acceleration response of the T-shaped plate. The response is converted into symbolic sequences with the multi-segmented coarse-grained method. The LZC of the response of 240 points located in different areas near the center is calculated. The results show that LZC arithmetic applied to elastomer vibration can satisfy the discreteness condition.

关键词： COMPUTATIONAL complexity VIBRATION (Mechanics) ALGORITHMS ACCELERATION (Mechanics) ELASTOMERS PLATES (Engineering)

A Novel OFDM Receiver with Optimum Second Order Polynomial Nyquist Windowing

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 84-89,102页

作者： song rong-fang AI Si LEUNG Shu-hung College of Telecommunications and Information Engineering Nanjing University of P~ts and Telecommunications Nanjing 210003 P.R. China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 P.R. China Department of Electronic Engineering City University of Hong Kong Kowloon Hong Kong P.R. China

This paper proposes a new receive scheme and a class of time domain second order polynomial Nyquist window functions, and applies them to Orthogonal Frequency-Division Multiplexing （ OFDM ） systems in order to reduce Inter-Carrier Interference （ICI） induced by frequency offset. This paper also analyzes the Signal to ICI plus Noise Ratio （SINR） and Bit Error Rate （BER） performances of the receiver. Additionally, this paper proposes a method to select optimum window parameters to maximize the SINR of the receiver thus providing an adaptive receiving capability. Our results show that the proposed method enables the use of unity roll-off factor, provides better SINR and BER than conventional receive methods whose roll-off factors are generally less than one. The new second order polynomial window is shown to provide better performance than raised cosine and ＂better than ＂ Nyquist window.

关键词： OFDM Nyquist window inter-carrier interference carrier frequency offset

Assessing satellite-derived net surface radiative flux in the Arctic

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Atmospheric and Oceanic Science Letters 2018年第2期11卷 209-217页

作者： song Mi-rong LIU Ji-Ping State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Department of Atmospheric and Environmental Sciences University at Albany State University of New YorkAlbanyNYUSA

Satellite-derived surface radiative fluxes have been recently improved and ***,the accuracy of recent satellite-derived surface radiative fluxes in the Arctic is not well ***,the authors assess the accuracy of the net surface radiative flux （NETSRF） in the Arctic,focusing on the ice-covered ocean,for three satellite products against four in situ measurements collected from different areas in the *** three satellite products are the Surface Radiation Budget project （SRB）,the International Satellite Cloud Climatology Project （ISCCP）,and the Extended AVHRR Polar Pathfinder version-2 （APP-x）.Our comparisons suggest that：（1） in terms of the overall bias,root-mean-square error,and correlation,the NETSRF of ISCCP is closer to in situ observations than that of SRB and APP-x;（2） in terms of the diurnal variation of the biases,it is not very clear which satellite product is superior to the others;and （3） in terms of the interannual variability of the bias,the NETSRF of ISCCP is more accurate than that of SRB and *** comparison may provide useful guidance to the community as to which data-set may provide the smallest bias in NETSRF

关键词： Arctic net surface radiation in situ measurement satelliteretrieval

Properties of second harmonic generation in nonlinear optical crystals CsLiB_6O_(10) and K_2Al_2B_2O_7

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 77-80页

作者： song Chun-rong ZHAO Jian-jun LIU JIn Department of Basic Courses Ordnance Engineering College Shijiazhuang 050003 China

The phase-matching for nonlinear optical crystal, the nonlinear phase matching angle, effective nonlinear coefficient, walk-off angles, permitted angle, and permitted wavelength are obtained in type-I and type-II phase matching in ultraviolet （UV） nonlinear optical crystals CsLiB6O10 （CLBO） and K2Al2B2O7 （KABO） by detailed theoretical simulation. Through analysis and comparison, the phase matching characteristics of the second harmonic generation in the crystals are discussed when the wavelengths of the basic frequency lights turn continually.

关键词： nonlinear optical crystals phase matching second harmonic generation (SHG) properties

Genetic Diversity： Geographical Distribution and Toxin Profiles of Microcystis Strains （Cyanobacteria） in China

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Journal of Integrative Plant Biology 2007年第3期49卷 262-269页

作者： Zhong-Xing Wu Nan-Qin Gan Li-rong song State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology the Chinese Academy of Sciences Wuhan 430072 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Twenty strains of Microcystis Kütz were isolated from different freshwater bodies in China to analyze the diversity, geographical distribution and toxin profiles. Based on whole-cell polymerase chain reaction of cpcBA-IGS nucleotlde sequence, the derived neighbor-joining （NJ） and maximum parsimony （MP） trees Indicate that these strains of Microcystis can be divided into four clusters. The strains from south, middle and north region of China formed distinct lineages, suggesting high diversity and a geographical distribution from south to north locations. Moreover, the results being indicating high variable genotypes of the strains of the Microcystis strains from the same lake show that there Is high diversity of Microcystis within a water bloom population. Comparing the results of the present study with those reported for compared with 43 strains of Microcystis from other locations, also reveals Chinese strains have high similarity with those from regions in the North Hemispherical. This suggests that the Microcystis strains In the world might have a geographical distribution. Analysis of 30 strains using the primers MCF/TER and TOX2P/TOX2M showed that there was no correlation between the gene of cpcBA-IGS and the presence of racy. Toxic strains were founded to be predominant in different water bodies throughout China.

关键词： diversity geographical distribution microcystin Microcystis

Prediction of ILI following the COVID-19 pandemic in China by using a partial differential equation

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Chinese Physics B 2024年第11期33卷 118-128页

作者： Xu Zhang Yu-rong song Ru-Qi Li School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China

The COVID-19 outbreak has significantly disrupted the lives of individuals *** the lifting of COVID-19 interventions,there is a heightened risk of future outbreaks from other circulating respiratory infections,such as influenza-like illness(ILI).Accurate prediction models for ILI cases are crucial in enabling governments to implement necessary measures and persuade individuals to adopt personal precautions against the *** paper aims to provide a forecasting model for ILI cases with actual *** propose a specific model utilizing the partial differential equation(PDE)that will be developed and validated using real-world data obtained from the Chinese National Influenza *** model combines the effects of transboundary spread among regions in China mainland and human activities’impact on ILI transmission *** simulated results demonstrate that our model achieves excellent predictive ***,relevant factors influencing the dissemination are further examined in our ***,we investigate the effectiveness of travel restrictions on ILI *** can be used to utilize to mitigate the spread of disease.

关键词： partial differential equations influenza SIS model prediction

The microbiota in spider mite feces potentially reflects intestinal bacterial communities in the host

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Insect Science 2020年第5期27卷 859-868页

作者： Yu-Xi Zhu Zhang-rong song Yue-Ling song Dian-Shu Zhao Xiao-Yue Hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

Microorganisms prov ide many physiological functions to herbivorous *** mites(genus Tetranychus)are important agricultural pests throughout the world;however,the composition of the spider mite microbial community,especially gut micro-biome,remains ***,we investigated the bacterial community in five spider mite species and their associated feces by deep sequencing of the 16S rRNA *** composi-tion of the bacterial community was significantly different among the five prevalent spider mite species,and some bacterial symbionts showed host-species ***,the abundance of the bacterial community in spider mite feces was significantly higher than that in the corresponding spider mite ***,Flavobacterium was detected in all samples,and represent a"core microbiome".Remarkably,the maternally inherited endosymbiont Wolbachia was detected in both spider mite and ***,these results offer insight into the complex community of symbionts in spider mites,and give a new direction for future studies.

关键词： bacterial community fces 16S rRNA spider mite Wolbachia

Effects of solidification cooling rate on the corrosion resistance of Mg–Zn–Ca alloy

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Progress in Natural Science:Materials International 2014年第5期24卷 452-457页

作者： Debao Liu Yichi Liu Yan Huang rong song Minfang Chen School of Materials Science and Engineering Tianjin University of Technology BCAST Brunel University

This study was carried out to investigate the effect of solidification cooling rate on the corrosion resistance of an Mg–Zn–Ca alloy developed for biomedical applications. A wedge shaped copper mould was used to obtain different solidification cooling rates. Electrochemical and immersion tests were employed to measure the corrosion resistance of Mg–Zn–Ca alloy. It was found that increasing cooling rate resulted in a significant improvement in the corrosion resistance of the Mg–Zn–Ca alloy. The findings were explained in terms of solidification behaviour in association with the change in solubility of the alloying elements, microstructural homogeneity and refinement and chemical homogeneity as well as the increased cooling rates.

关键词： Mg–Zn–Ca alloy Solidification cooling rate Microstructure Corrosion resistance