Alzheimer＇s disease （AD）, the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been...Alzheimer＇s disease （AD）, the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been estimated that dementia affects over 47 million people worldwide （Prince et al., 2015）, and with 60-80% of cases attributable to AD.展开更多
Based on the complex variable moving least-square（CVMLS） approximation and a local symmetric weak form,the complex variable meshless local Petrov-Galerkin（CVMLPG） method of solving two-dimensional potential proble...Based on the complex variable moving least-square（CVMLS） approximation and a local symmetric weak form,the complex variable meshless local Petrov-Galerkin（CVMLPG） method of solving two-dimensional potential problems is presented in this paper.In the present formulation,the trial function of a two-dimensional problem is formed with a one-dimensional basis function.The number of unknown coefficients in the trial function of the CVMLS approximation is less than that in the trial function of the moving least-square（MLS） approximation.The essential boundary conditions are imposed by the penalty method.The main advantage of this approach over the conventional meshless local Petrov-Galerkin（MLPG） method is its computational efficiency.Several numerical examples are presented to illustrate the implementation and performance of the present CVMLPG method.展开更多
By simulating the electron paramagnetic resonance （EPR） and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl...By simulating the electron paramagnetic resonance （EPR） and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl：V2＋ （M=Na, K, Rb） systems at 77K, 195 K and RT （room temperature 295 K or 302 K）, respectively. The theoretical results indicate that there exists a compressed distortion in MCl：V2＋ systems. Meanwhile, it finds that the structure parameters R1, R2 and ｜△R｜（ = R1 - R2） increase with the rising temperature. Subsequently, from the analysis it concludes that the relation of EPR parameter D vs. △R is approximately linear. Finally, the effects of orbital reduction factor k on the g factors for the three systems have been discussed.展开更多
In this paper, a new mechanism for the emergence of scale-free distribution is proposed. It is more realistic than the existing mechanism. Based on our mechanism, a model responsible for the scale-free distribution wi...In this paper, a new mechanism for the emergence of scale-free distribution is proposed. It is more realistic than the existing mechanism. Based on our mechanism, a model responsible for the scale-free distribution with an exponent in a range of 3-to-5 is given. Moreover, this model could also reproduce the exponential distribution that is discovered in some real networks. Finally, the analytical result of the model is given and the simulation shows the validity of our result,展开更多
A weighted Koppelman-Leray-Norguet formula of (r, s) differential forms on a local q-concave wedge in a complex manifold is obtained. By constructing the new weighted kernels, the authors give a new weighted Koppelman...A weighted Koppelman-Leray-Norguet formula of (r, s) differential forms on a local q-concave wedge in a complex manifold is obtained. By constructing the new weighted kernels, the authors give a new weighted Koppelman-Leray-Norguet formula without boundary integral of (r, s) differential forms, which is different from the classical one. The new weighted formula is especially suitable for the case of the local g-concave wedge with a non-smooth boundary, so one can avoid complex estimates of boundary integrals and the density of integral may be not defined on the boundary but only in the domain. Moreover, the weighted integral formulas have much freedom in applications such as in the interpolation of functions.展开更多
With the help of the symbolic computation system Maple, the Riccati equation mapping approach and a linear variable separation approach, a new family of complex solutions for the （2＋ 1）-dimensional Boiti-Leon-Pempi...With the help of the symbolic computation system Maple, the Riccati equation mapping approach and a linear variable separation approach, a new family of complex solutions for the （2＋ 1）-dimensional Boiti-Leon-Pempinelli system （BLP） is derived. Based on the derived solitary wave solution, some novel complex wave localized excitations are obtained.展开更多
同步定位与建图(simultaneous localization and mapping, SLAM)技术是移动机器人研究及应用的关键问题,旨在解决机器人在复杂环境中实现自主定位与地图构建等功能。对SLAM的系统组成、关键技术及应用进行了简要介绍;重点围绕特征点法...同步定位与建图(simultaneous localization and mapping, SLAM)技术是移动机器人研究及应用的关键问题,旨在解决机器人在复杂环境中实现自主定位与地图构建等功能。对SLAM的系统组成、关键技术及应用进行了简要介绍;重点围绕特征点法、滤波法、图优化法、多传感器融合和动态场景5个方面,综述了SLAM系统的关键技术、国内外研究现状及标志性应用进展;并结合代表性系统,比较分析了不同方法之间的优缺点,详细阐述了多传感器融合SLAM系统,同时对复杂场景下的SLAM技术进行了展望。展开更多
The formation of shear bands in metallic glasses(MGs)was examined by tailoring localized complex stress fields(LCSFs).The findings have shown that the LCSFs in MGs can increase the localization of strained atoms and a...The formation of shear bands in metallic glasses(MGs)was examined by tailoring localized complex stress fields(LCSFs).The findings have shown that the LCSFs in MGs can increase the localization of strained atoms and accelerate the release of accumulated deformation energy for initiating a shear band in confined and thin-layered regions.The findings not only add more knowledge to the formation mechanisms of shear bands in MGs,but also provide possible rationale for the discrepancies in the mechanical properties of different-sized MGs.As compared with the bulk samples,the higher strength and larger elastic limits in nanoscaled MGs could be attributed to the elimination of stress-concentrators,which can serve as LCSFs.展开更多
By considering the eigenratio of the Laplacian matrix as the synchronizability measure, this paper presents an efficient method to enhance the synchronizability of undirected and unweighted networks via rewiring. The ...By considering the eigenratio of the Laplacian matrix as the synchronizability measure, this paper presents an efficient method to enhance the synchronizability of undirected and unweighted networks via rewiring. The rewiring method combines the use of tabu search and a local greedy algorithm so that an effective search of solutions can be achieved. As demonstrated in the simulation results, the performance of the proposed approach outperforms the existing methods for a large variety of initial networks, both in terms of speed and quality of solutions.展开更多
In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new...In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new local-world evolving network model is proposed in this paper. In the model, not all the nodes obtain local network information, which is different from the local world network model proposed by Li and Chen （LC model）. In the LC model, each node has only the local connections therefore owns only local information about the entire networks. Theoretical analysis and numerical simulation show that adjusting the ratio of the number of nodes obtaining the global information of the network to the total number of nodes can effectively control the valuing range for the power-law exponent of the new network. Therefore, if the topological structure of a complex network, especially its exponent of power-law degree distribution, needs controlling, we just add or take away a few nodes which own the global information of the network.展开更多
Due to the fact that traditional ray field tracking approaches require a large number of geometrical optical（GO） ray tubes,they are very inefficient in many practical applications.An improved ray model scheme for a ...Due to the fact that traditional ray field tracking approaches require a large number of geometrical optical（GO） ray tubes,they are very inefficient in many practical applications.An improved ray model scheme for a complex source beam（CSB） tracking technique is proposed in this paper.The source field can be expressed by a superposition of CSBs,then every CSB basis function has a Gaussian-type amplitude distribution and is suitable for replacing a GO ray tube in the ray tracing approach.The complex phase matching technique is adopted to find the reflected beam in the reflection point where local approximation is used to represent the curved surface in its neighborhood.A new solution to multiple reflections using the conventional right-handed reflected system is used to track the field easily.Numerical results show the accuracy of the proposed method.展开更多
文摘Alzheimer＇s disease （AD）, the predominant form of dementia, is a chronic, incurable neurodegenerative disorder presenting with symptoms includ- ing progressive memory loss and disturbed emotional state. It has been estimated that dementia affects over 47 million people worldwide （Prince et al., 2015）, and with 60-80% of cases attributable to AD.
基金Project supported by the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 11102125)
文摘Based on the complex variable moving least-square（CVMLS） approximation and a local symmetric weak form,the complex variable meshless local Petrov-Galerkin（CVMLPG） method of solving two-dimensional potential problems is presented in this paper.In the present formulation,the trial function of a two-dimensional problem is formed with a one-dimensional basis function.The number of unknown coefficients in the trial function of the CVMLS approximation is less than that in the trial function of the moving least-square（MLS） approximation.The essential boundary conditions are imposed by the penalty method.The main advantage of this approach over the conventional meshless local Petrov-Galerkin（MLPG） method is its computational efficiency.Several numerical examples are presented to illustrate the implementation and performance of the present CVMLPG method.
基金Project supported by the National Natural Science Foundation of China (Grant No 10774103)the Doctoral Education Fund of the Education Ministry of China (Grant No 20050610011)
文摘By simulating the electron paramagnetic resonance （EPR） and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl：V2＋ （M=Na, K, Rb） systems at 77K, 195 K and RT （room temperature 295 K or 302 K）, respectively. The theoretical results indicate that there exists a compressed distortion in MCl：V2＋ systems. Meanwhile, it finds that the structure parameters R1, R2 and ｜△R｜（ = R1 - R2） increase with the rising temperature. Subsequently, from the analysis it concludes that the relation of EPR parameter D vs. △R is approximately linear. Finally, the effects of orbital reduction factor k on the g factors for the three systems have been discussed.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 60374037 and 60574036）, the Program for New Century Excellent Talents of High Education of China（Grant No NCET 2005-290）, The Special Research Fund for the Doctoral Program of High Education of China （Grant No 20050055013）.Acknowledgments The authors would like to thank Réka Albert for useful discussion and are grateful to the anonymous referees for their valuable suggestions and comments, which have made this paper improved.
文摘In this paper, a new mechanism for the emergence of scale-free distribution is proposed. It is more realistic than the existing mechanism. Based on our mechanism, a model responsible for the scale-free distribution with an exponent in a range of 3-to-5 is given. Moreover, this model could also reproduce the exponential distribution that is discovered in some real networks. Finally, the analytical result of the model is given and the simulation shows the validity of our result,
基金National Natural Science Foundation and Mathematical "Tian Yuan" Foundation of China (10271097 and TY10126033)
文摘A weighted Koppelman-Leray-Norguet formula of (r, s) differential forms on a local q-concave wedge in a complex manifold is obtained. By constructing the new weighted kernels, the authors give a new weighted Koppelman-Leray-Norguet formula without boundary integral of (r, s) differential forms, which is different from the classical one. The new weighted formula is especially suitable for the case of the local g-concave wedge with a non-smooth boundary, so one can avoid complex estimates of boundary integrals and the density of integral may be not defined on the boundary but only in the domain. Moreover, the weighted integral formulas have much freedom in applications such as in the interpolation of functions.
基金Project supported by the National Natural Science Foundation of China(Grant No.11375079)the Natural Science Foundation of Zhejiang Province,China(Grant Nos.Y6100257 and Y6110140)
文摘With the help of the symbolic computation system Maple, the Riccati equation mapping approach and a linear variable separation approach, a new family of complex solutions for the （2＋ 1）-dimensional Boiti-Leon-Pempinelli system （BLP） is derived. Based on the derived solitary wave solution, some novel complex wave localized excitations are obtained.
文摘同步定位与建图(simultaneous localization and mapping, SLAM)技术是移动机器人研究及应用的关键问题,旨在解决机器人在复杂环境中实现自主定位与地图构建等功能。对SLAM的系统组成、关键技术及应用进行了简要介绍;重点围绕特征点法、滤波法、图优化法、多传感器融合和动态场景5个方面,综述了SLAM系统的关键技术、国内外研究现状及标志性应用进展;并结合代表性系统,比较分析了不同方法之间的优缺点,详细阐述了多传感器融合SLAM系统,同时对复杂场景下的SLAM技术进行了展望。
基金financially supported by the National Natural Science Foundation of China(Nos.51801049 and 51801174)the State Key Laboratory of Metastable Materials Science and Technology,Yanshan University(No.201809)the Fundamental Research Funds for the Central Universities of China(Nos.PA2019GDZC0096 and JD2019JGPY0015)。
文摘The formation of shear bands in metallic glasses(MGs)was examined by tailoring localized complex stress fields(LCSFs).The findings have shown that the LCSFs in MGs can increase the localization of strained atoms and accelerate the release of accumulated deformation energy for initiating a shear band in confined and thin-layered regions.The findings not only add more knowledge to the formation mechanisms of shear bands in MGs,but also provide possible rationale for the discrepancies in the mechanical properties of different-sized MGs.As compared with the bulk samples,the higher strength and larger elastic limits in nanoscaled MGs could be attributed to the elimination of stress-concentrators,which can serve as LCSFs.
基金Project supported by the grant from City University of Hong Kong (Grant No. 7008105)
文摘By considering the eigenratio of the Laplacian matrix as the synchronizability measure, this paper presents an efficient method to enhance the synchronizability of undirected and unweighted networks via rewiring. The rewiring method combines the use of tabu search and a local greedy algorithm so that an effective search of solutions can be achieved. As demonstrated in the simulation results, the performance of the proposed approach outperforms the existing methods for a large variety of initial networks, both in terms of speed and quality of solutions.
基金supported by the Scientific Research Starting Foundation of Hangzhou Dianzi University (Grant No KYS091507073)partly by the National High Technology Research and Development Program of China (Grant No 2005AA147030)
文摘In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new local-world evolving network model is proposed in this paper. In the model, not all the nodes obtain local network information, which is different from the local world network model proposed by Li and Chen （LC model）. In the LC model, each node has only the local connections therefore owns only local information about the entire networks. Theoretical analysis and numerical simulation show that adjusting the ratio of the number of nodes obtaining the global information of the network to the total number of nodes can effectively control the valuing range for the power-law exponent of the new network. Therefore, if the topological structure of a complex network, especially its exponent of power-law degree distribution, needs controlling, we just add or take away a few nodes which own the global information of the network.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61301056 and 61231001)the Fundamental Research Funds for the Central Universities,China(Grant No.ZYGX2014J012)+2 种基金the Fok Ying Tung Education Foundation,China(Grant No.141062)the Aero-Science Fund,China(Grant No.20142580012)the"111"Project(Grant No.B07046)
文摘Due to the fact that traditional ray field tracking approaches require a large number of geometrical optical（GO） ray tubes,they are very inefficient in many practical applications.An improved ray model scheme for a complex source beam（CSB） tracking technique is proposed in this paper.The source field can be expressed by a superposition of CSBs,then every CSB basis function has a Gaussian-type amplitude distribution and is suitable for replacing a GO ray tube in the ray tracing approach.The complex phase matching technique is adopted to find the reflected beam in the reflection point where local approximation is used to represent the curved surface in its neighborhood.A new solution to multiple reflections using the conventional right-handed reflected system is used to track the field easily.Numerical results show the accuracy of the proposed method.
