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Integrated evaluation approach for node importance of complex networks based on relative entropy

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Journal of Systems Engineering and Electronics 2016年第6期27卷 1219-1226页

作者： Bin chen Zhixue Wang chen luo Institute of Command Information System PLA University of Science and Technology

Evaluating the node importance correctly is a crucial issue for complex networks research. If a network has multiple or ambiguous morphological features, the evaluation result of an individual index may be unilateral. Meanwhile, the results may be inconsistent if different indexes are adopted simultaneously. To solve the problem, an integrated approach is proposed based on relative entropy. In this approach, a system of multiple indexes is constructed firstly. Then each evaluation result of an individual index is handled into a discrete distribution. Finally an optimal integrated evaluation solution is obtained by linear programming. This approach has a well-formed theoretic basis and an easilycalculated procedure, which can be used in a variety of complex networks. Experimental results show that the proposed approach is more effective than other different methods proposed in some literatures. © 2016 Beijing Institute of Aerospace Information.

关键词： Entropy Linear programming

Joint angle and frequency estimation for linear array:an extended DOA-matrix method

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Journal of Systems Engineering and Electronics 2022年第4期33卷 887-895页

作者： chen luo DAI Xiangrui ZHANG Xiaofei College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China The 28th Research Institute of China Electronics Technology Group Corporation Nanjing 210007China

An approach for joint direction of arrival(DOA) angle and frequency estimation for a linear array is investigated in this paper. Specifically, we make the utmost of the autocorrelation and cross-correlation information to propose an extended DOAmatrix(EDOAM) method. Subsequently, we obtain the autopaired angle and frequency estimates by the eigenvalues and the corresponding eigenvectors of the novel DOA matrix. Furthermore, the proposed method surpasses the DOA-matrix method which partly ignores the autocorrelation and cross-correlation information. Finally, the proposed method works well for both uniform and non-uniform linear arrays. The simulation consequences indicate the superiority of our proposed approach.

关键词： direction of arrival(DOA) frequency linear array time delay extended DOA-matrix method

Fitness of Encarsia sophia （Hymenoptera： Aphelinidae） parasitizing Trialeurodes vaporariorum and Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect Science 2011年第1期18卷 84-91页

作者： chen luo Tong-Xian Liu Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry Sciences Beijing Key Laboratory of Applied Entomology Northwest A&F University Yangling Shaanxi Province China

Fitness and efficacy of Encarsia sophia （Girault ＆ Dodd）（Hymenoptera： Aphelinidae） as a biological control agent was compared on two species of whitefly （Hemiptera： Aleyrodidae） hosts, the relatively smaller sweetpotato whitefly, Bemisia tabaci （Gennadius） biotype ＇B＇, and the larger greenhouse whitefly, Trialeurodes vaporariorum （Westwood）. Significant differences were observed on green bean （Phaseolus vulgaris L.） in the laboratory at 27 ± 2℃, 55% 4- 5% RH, and a photoperiod of 14 ： 10 h （L ： D）. Adult parasitoids emerging from T. vaporariorum were larger than those emerging from B. tabaci, and almost all biological parameters of E. sophia parasitizing the larger host species were superior except for the developmental times of the parasitoids that were similar when para- sitizing the two host species. Furthermore, parasitoids emerging from T. vaporariorum parasitized more of these hosts than did parasitoids emerging from B. tabaci. We conclude that E. sophia reared from larger hosts had better fitness than from smaller hosts. Those from either host also preferred the larger host for oviposition but were just as effective on smaller hosts. Therefore, larger hosts tended to produce better parasitoids than smaller hosts.

关键词： biological control body size host size oviposition sweetpotato whitefly

Effect of Dy substitution on the microstructure and magnetic properties of nanograin Nd-Fe-B single-phase alloys

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 335-339页

作者： Zhi-an chen Ji luo Zhi-meng Guo School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanocrystalline single-phase alloys with the nominal compositions （at%） of Nd12.3-xDyxFe79.7Zr0.8Nb0.8Cu0.4B6.0 （x=0, 0.5, 1.5, and 2.5） were prepared by melt-spinning and subsequent annealing. X-ray diffraction analysis shows that the as-spun ribbons were mainly com- posed of the amorphous phase. A slight content of Dy stabilizes the amorphous phase during annealing treatment. The grain size becomes smaller and the coercivity of the annealed ribbon is gradually improved with the increase of Dy content. Excessive Dy is harmful to the remanence. It is found that no intergramtlar phase exists between the grains by high-resolution transmission electron microscopy, and the grain boundaries are crystallographically coherent in the optimally annealed sample. The optimum magnetic properties of remanence （Jr=1.09 T）, coercivity （Hei=1048 kA/m）, and maximum magnetic energy product （（BH）m=169.5 kJ/m3） are obtained from the x=0.5 ribbon in a post heat-treated state （700℃, 10 min）.

关键词： NdFeB magnets dysprosium nanocrystalline amorphous grain size magnetic properties

KMcube： the compound of Kautz digraph and Moibius cube

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Frontiers of Computer Science 2013年第2期7卷 298-306页

作者： Xianpeng HUANGFU Deke GUO Honghui chen Xueshan luo National Key Laboratory of Information System Engineering School of Information System and Management National University of Defense TechnologyChina Changsha 410073

This paper introduces a novel interconnection network called KMcube （Kautz-Mobius cube）. KMcube is a compound graph of a Kautz digraph and M/Sbius cubes. That is, it uses the Mobius cubes as the unit cluster and connects many such clusters by means of a Kautz digraph at the cost of only one additional arc being added to any node in each Mobius cubes. The topological benefits of both basic graphs are preserved in the compound network. It utilizes the topo- logical properties of Mobius cubes to conveniently embed parallel algorithms into each cluster and the short diameter of a Kautz digraph to support efficient inter-cluster communi- cation. Additionally, KMcube provides other attractive prop- erties, such as the regularity, symmetry, and expandability. The proposed methodology for KMcube is further applied to the compound graphs of Kautz digraph and other Mobius-like graphs with the similar diameter to a Mobius cube. Moreover, other hybrid graphs of Kautz digraph and Mobius cubes are proposed and compared.

关键词： interconnection network Kautz digraphM6bius cube compound graph

On the rate of convergence for multi-category classification based on convex losses

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Science China Mathematics 2007年第11期50卷 1529-1536页

作者： Hong chen luo-qing LI Faculty of Mathematics and Computer Science Hubei UniversityWuhan 430062China Faculty of Mathematics and Computer ScienceHubei UniversityWuhan 430062China

The multi-category classification algorithms play an important role in both theory and practice of machine *** this paper,we consider an approach to the multi-category classification based on minimizing a convex surrogate of the nonstandard misclassification *** bound the excess misclassification error by the excess convex *** construct an adaptive procedure to search the classifier and furthermore obtain its convergence rate to the Bayes rule.

关键词： misclassiflcation error consistency convergence rate

vsx1 3' untranlated region-mediated translation difference at different developmental stages of goldfish embryos

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Journal of Genetics and Genomics 2009年第8期36卷 483-490页

作者： Jinhui chen Ying Tong Shufang Zhao Shanshan Ma chen luo College of Life Science Hunan Normal University Changsha 410081 China College of Life Science Zhejiang University Hangzhou 310058 China

Visual system homeobox-1 （vsxl） is important in retinal progenitor proliferation, differentiation, and function maintenance of bipolar cells in vertebrates. Recent study in Xenopus laevis has shown that vsxl 3＇ untranslated region （3＇ UTR） can mediate cell-specific translation of vsxl mRNA in the bipolar cells of the retinal inner nuclear layer （INL）. vsxl is also transcribed at the early developmental stages prior to eye formation and its spatiotemporal expression patterns are conserved in all the examined vertebrates. In order to determine whether the vsxl 3＇ UTR has a role in regulating the spatiotemporal expression of vsxl during early embryogenesis, we constructed a vsxl UTR-controlled green fluorescent protein （GFP） reporter gene system and examined the GFP expression pattern in goldfish, Carassius auratus, at different developmental stages, Our results indicated that both the vsxl 5＇ UTR and the vsxl 3＇ UTR remarkably repressed GFP expression at transcription level but did not regulate tissue-specific translation at early developmental stages. GFP protein was ubiquitously expressed in the embryos injected with GFP-sensors containing vsxl UTRs before 60 h post-fertilization （hpf）. From hatching stage （72 hpf） onwards, however, GFP protein was specifically expressed in the bipolar cells of the retinal 1NL in the vsxl 3＇UTR-GFP-sensor embryos, but was still ubiquitously expressed in the embryos injected with GFP-sensor lacking vsxl 3＇ UTR. These observations showed a significant difference of vsxl 3＇ UTR-mediated translation between early and late developmental stages and suggested that vsxl 3＇ UTR might not be involved in regulating the spatiotemporal expression of vsxl until hatching stage during embryogenesis.

关键词： vsxl untranslated region gene expression spatiotemporal pattern goldfish embryo

Generalized Parallel Coprime Array for Two-Dimensional DOA Estimation:A Perspective from Maximizing Degree of Freedom

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China Communications 2021年第4期18卷 14-26页

作者： luo chen Xinping Lin Beizuo Zhu Xiaofei Zhang College of Electronic Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyNanjing 211106China The 28th Research Institute of China Electronics Technology Group Corporation Nanjing 210007China

Parallel arrays with coprime subarrays have shown its potential advantages for two dimensional direction of arrival(DOA)*** this paper,by introducing two flexible coprime factors to enlarge the inter-element spacing of parallel uniform subarrays,we propose a generalized parallel coprime array(GPCA)*** proposed geometry enjoys flexible array layouts by the coprime factors and enables to extend the array aperture to achieve great improvement of estimation ***,we verify that GPCA always can obtain M2 degrees of freedom(DOFs)in co-array domain via 2M sensors after optimization,which outperforms sparse parallel array geometries,such as parallel coprime array(PCA)and parallel augmented coprime array(PACA),and is the same as parallel nested array(PNA)with extended *** superiority of GPCA geometry has been proved by numerical simulations with sparse representation methods.

关键词： direction of arrival estimation generalized parallel coprime array degrees of freedom array aperture coprime factors

A TVD discretization method for shallow water equations:Numerical simulations of tailing dam break

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第3期8卷 338-359页

作者： chen luo Ke Xu Yunsheng Zhao College of Engineering China University of Geosciences Room 401 Structure Building388 Lumo Road Hongshan DistrictWuhan 430074P.R.China Safety Science and Technology Research Center University of Science and Technology Beijing Room 305 Main Building30 Wuluo Road Wuchang DistrictWuhan 430074P.R.China

In view of the disastrous consequences of tailings dam break and its unique evolutionary process in complex areas,this paper constructs two-dimensional shallow water equations,rheological equations and mathematical models of tailings sand flows on the basis of Navier–Stokes equations(N–S equations).It performs total variation diminishing(TVD)discretization on these equations,develops forward simulation programs in MATLAB2016 and conducts numerical analyses on three kinds of dam breaks(ideal dam break,asymmetric dam break and dam break with obstacles in the downstream area).The results show that TVD discretization is effective in capturing shock *** to the analysis on consequences of Huangmailing Tailings Dam break,the author obtains the maximum distance of tailings sand flow,the flow rate of tailings and the time that tailings reach destinations in the downstream area,thereby providing scientific basis for disaster analyses on similar tailings dam breaks and supplying technical support for emergency rescues after disasters.

关键词： Tailings reservoir dam-break sand flow model two-dimensional shallow water equation total variation diminishing discretization