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ESTIMATION OF AVERAge DIFFERENTIAL ENTROPY FOR A STATIONARY ERGODIC SPACE-TIME RANDOM FIELD ON A BOUNDED AREA

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Acta Mathematica Scientia 2024年第5期44卷 1984-1996页

作者： Zhanjie song Jiaxing ZHANG georgia Tech Shenzhen Institute Tianjin UniversityShenzhen518055China Tianjin Key Laboratory of Brain-Inspired Intelligence Technology Tianjin300072China School of Mathematics Tianjin UniversityTianjin300354China

In this paper,we mainly discuss a discrete estimation of the average differential entropy for a continuous time-stationary ergodic space-time random *** estimating the probability value of a time-stationary random field in a small range,we give an entropy estimation and obtain the average entropy estimation formula in a certain bounded space *** can be proven that the estimation of the average differential entropy converges to the theoretical value with a probability of *** addition,we also conducted numerical experiments for different parameters to verify the convergence result obtained in the theoretical proofs.

关键词： differential entropy stationary ergodicity space-time random field time series

Topological Features Based Entity Disambiguation

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Journal of Computer Science & Technology 2016年第5期31卷 1053-1068页

作者： Chen-Chen Sun De-Rong Shen Yue Kou Tie-Zheng Nie ge Yu School of Computer Science and Engineering Northeastern University Shenyang 110819 China

This work proposes an unsupervised topological features based entity disambiguation solution. Most existing studies leverage semantic information to resolve ambiguous references. However, the semantic information is not always accessible because of privacy or is too expensive to access. We consider the problem in a setting that only relationships between references are available. A structure similarity algorithm via random walk with restarts is proposed to measure the similarity of references. The disambiguation is regarded as a clustering problem and a family of graph walk based clustering algorithms are brought to group ambiguous references. We evaluate our solution extensively on two real datasets and show its advantage over two state-of-the-art approaches in accuracy.

关键词： entity disambiguation topological feature clustering random walk with restarts

POLY(MALEIC ANHYDRIDE-CO-ACRYLIC ACID)/POLY(ETHYLENE GLYCOL)HYDROgeLS WITH pH- AND IONIC-STRENGTH-RESPONSES

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Chinese Journal of Polymer Science 2010年第6期28卷 951-959页

作者： Meng yang Bo-tian Liu ge Gao Xiao-li Liu Feng-qi Liu College of Chemistry and Macdiarmid Laboratory Jilin University Changchun 130012 China

Poly（maleic anhydride-coacrylic acid）,P（MA-AA）,was synthesized by the free-radical copolymerization of maleic anhydride with acrylic acid,and fast responsive pH-sensitive poly（maleic anhydride-co-acrylic acid）/polyethylene glycol,P（MA-AA）/PEG,hydrogels were prepared using PEG as macromolecular cross-linking ***-IR and ~1H-NMR spectrometry were applied to characterize the structure of P（MA-AA）.The influences of pH and ionic strength on the swelling behavior of P（MA-AA）/PEG hydrogels and the swelling-deswelling changes along with the repeated changes between acid and alkali conditions were *** results showed that there was a hundredfold difference in the swelling ratios between the conditions of acid and alkali,and the swelling capability could not be weakened after multiple swelling-deswelling *** results of swelling kinetics demonstrated that the response rate of P（MA-AA）/PEG hydrogels was very fast,because the swelling transition points always occurred at 10 *** pH-responsive hydrogels reported here might be a smart material for potentially applications in many areas,including biosensors,drug-delivery devices and tissue engineering.

关键词： pH-response P(MA-AA) Macromolecular cross-linking agent External cross-linking

The atom-bond connectivity index of chemical bicyclic graphs

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 243-252页

作者： CHEN Jin-song GUO Xiao-feng College of Mathematics and Computer Science Hunan Normal University Changsha 410081 China. College of Mathematics and Computer Science Fuzhou University Fuzhou 350108 China. School of Mathematical Sciences Xiamen University Xiamen 361005 China.

The atom-bond connectivity（ABC） index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC（G） =∑ uv∈E（G） √d u＋dv-2 dudv,where du denotes the degree of a vertex u in G.A chemical graph is a graph in which no vertex has degree greater than *** this paper,we obtain the sharp upper and lower bounds on ABC index of chemical bicyclic graphs.

关键词： atom-bond connectivity index chemical bicyclic graph bound.

Contribution of intraseasonal oscillation to long-duration summer precipitation events over southern China

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Atmospheric and Oceanic Science Letters 2017年第1期10卷 82-88页

作者： LIU ge WU Ren-Guang WANG Hui-Mei State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of Sciences

Precipitation events spanning multiple days may have consequences different from those limited to a single *** the present paper,the authors analyze circulation anomalies and precursory signals associated with long-duration（over 14 days） summer precipitation events over southern *** results show that the over-14-day precipitation events are induced by an anomalous lowertropospheric（850-hPa） cyclone over the South China Sea（SCS） and southern *** anomalous westerly winds to the south of the anomalous cyclone can be traced to north of New Guinea 30 days *** the north of anomalous westerly winds,anomalous easterly winds appear *** anomalous westerly and easterly winds form a cyclonic anomaly,moving northward and slightly westward during the following days and eventually controlling the SCS and southern *** northward movement of anomalous westerly and easterly winds can also be found in the 30-60-day filtered wind *** implies that the northward propagating 30-60-day intraseasonal oscillation from the equatorial western Pacific has an important contribution to over-14-day precipitation events over southern China.

关键词： Precipitation event long duration southern China intraseasonal oscillation

Dynamic Deformation Behavior of Dual Phase Ferritic-Martensitic Steel at Strain Rates From 10^(-4)to 2000 s^(-1)

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Journal of Iron and Steel Research International 2013年第8期20卷 48-53页

作者： song Ren-bo DAI Qi-feng School of Materials Science and Engineering University of Science and Technology Beijing

The deformation behavior of the dual phase steel （DP1000 steel） was studied by the quasi-static tensile ex-periment and the dynamic tensile experiment. The experiments were carried out at strain rates ranging from 10^-4 to 2 000 s^-1 at room temperature. Then the stress-strain curves of DP1000 steel in the strain rate range of 10^-4-2000 s^-1 were measured. By introducing the strain rate sensitivity factor m, Zerilli Armstrong model was optimized. The con- stitutive equation parameters which formulate the mechanical behavior of DP1000 steel were fitted based on the John-son-Cook （JC） constitutive model and the optimized Zerilli-Armstrong （ZA） constitutive model, respectively. By comparing indicators of ＂accuracy-of-fit＂, Rz terms, for the two models, the optimized Zerilli-Armstrong constitu-tive model can reflect plastic deformation behavior both at the low and high strain rates more accurately. The reasons why the optimized Zerilli-Armstrong constitutive model is more advantageous than the Johnson Cook model were discussed by using the yield strength and ultimate tensile strength （UTS） versus strain rates, and strain hardening rate versus effective plastic strain analytical methods.

关键词： DP steel dynamic deformation behavior split Hopkinson tensile bar constitutive model strain ratesensitivity

New Monotonicity Formulae for Semi-linear Ellipti and Parabolic Systems

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Chinese Annals of Mathematics,Series B 2010年第3期31卷 411-432页

作者： Li MA Xianfa song Lin ZHAO Department of Mathematical Sciences Tsinghua University Beijing 100084 China. Department of Mathematics Tianjin University Tianjin 300072 China.

The authors establish a general monotonicity formula for the following elliptic system △ui＋fi（x,ui,…,um）=0 in Ω,where Ω belong to belong to R^n is a regular domain, （fi（x, u1,... ,um）） = △↓F（x,→↑u）, F（x,→↑u ） is a given smooth function of x ∈ R^n and →↑u = （u1,…,um） ∈ R^m. The system comes from understanding the stationary case of Ginzburg-Landau model. A new monotonicity formula is also set up for the following parabolic systemδtui-△ui-fi（x,ui,…,um）=0 in（ti,t2）×R^n,where t1 〈 t2 are two constants, （fi（x,→↑u ） is given as above. The new monotonicity formulae are focused more attention on the monotonicity of nonlinear terms. The new point of the results is that an index β is introduced to measure the monotonicity of the nonlinear terms in the problems. The index β in the study of monotonieity formulae is useful in understanding the behavior of blow-up sequences of solutions. Another new feature is that the previous monotonicity formulae are extended to nonhomogeneous nonlinearities. As applications, the Ginzburg-Landau model and some different generalizations to the free boundary problems are studied.

关键词： Elliptic systems Parabolic system Monotonicity formula Ginzburg-Landau model

Cross-Rack Updates in Vertical Array Codes Storage Systems with High Fault Tolerance

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Journal of Communications and Information Networks 2021年第2期6卷 184-196页

作者： Ruiting Lei Hanxu Hou Yue song School of Electrical Engineering&Intel-ligentization Dongguan University of TechnologyDongguan 523808China

Vertical array codes have less computational complexity and update complexity in comparison with horizontal array ***,the fault tolerance of the existing vertical array codes is in general lower than that of horizontal array *** addition,the cross-rack bandwidth is often the bottleneck of the update performance in erasure-coded storage *** this paper,we propose a cross-rack update(CRU)mechanism for vertical array codes intended to improve both the fault tolerance and update performance of erasure-coded storage *** builds on three parts:(i)stripe encoding,which can improve the fault tolerance of vertical code by encoding multiple sub-stripe;(ii)node grouping,which filters out the best combination of nodes to minimize cross-rack update traffic;(iii)selective logging,which can selectively log based on the location of data sub-blocks and parity sub-blocks to reduce disk I/O and cross-rack *** evaluate CRU via trace-driven analysis and local cluster *** show that CRU can significantly reduce cross-rack update traffic and improve system update throughput.

关键词： vertical array codes cross-rack update fault tolerance

Hereditarily covering properties of inverse sequence limits

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Frontiers of Mathematics in China 2013年第4期8卷 987-997页

作者： Bin ZHAO Aili song Jing WEI Department of Mathematics Kashi Teachers College Kashi 844007 China

Let {Xi,πki,ω} be an inverse sequence and X -- lim{Xi,πki,ω）. If each Xi is hereditarily （resp. metaLindelSf, σ-metaLindelSf, σ-orthocompact, weakly suborthocompact, δθ-refinable, weakly θ-refinable, weakly... 详细信息

关键词： Inverse sequence limit hereditarily metaLindelofness hereditarily weakly suborthocompactness hereditarily δθ-refinability hereditarily weakly θ-refinability countable product