Optimization problems are often highly constrained and evolutionary algorithms（EAs）are effective methods to tackle this kind of problems. To further improve search efficiency and convergence rate of EAs, this paper ...Optimization problems are often highly constrained and evolutionary algorithms（EAs）are effective methods to tackle this kind of problems. To further improve search efficiency and convergence rate of EAs, this paper presents an adaptive double chain quantum genetic algorithm（ADCQGA） for solving constrained optimization problems. ADCQGA makes use of doubleindividuals to represent solutions that are classified as feasible and infeasible solutions. Fitness（or evaluation） functions are defined for both types of solutions. Based on the fitness function, three types of step evolution（SE） are defined and utilized for judging evolutionary individuals. An adaptive rotation is proposed and used to facilitate updating individuals in different solutions.To further improve the search capability and convergence rate, ADCQGA utilizes an adaptive evolution process（AEP）, adaptive mutation and replacement techniques. ADCQGA was first tested on a widely used benchmark function to illustrate the relationship between initial parameter values and the convergence rate/search capability. Then the proposed ADCQGA is successfully applied to solve other twelve benchmark functions and five well-known constrained engineering design problems. Multi-aircraft cooperative target allocation problem is a typical constrained optimization problem and requires efficient methods to tackle. Finally, ADCQGA is successfully applied to solving the target allocation problem.展开更多
This book focuses on culture and discusses it from an archaeological perspective.It includes several aspects:to illustrate the uniqueness of the archaeological perspective,introduce the cultural evolution of the Paleo...This book focuses on culture and discusses it from an archaeological perspective.It includes several aspects:to illustrate the uniqueness of the archaeological perspective,introduce the cultural evolution of the Paleolithic Age,especially the birth of cultural modernity(anatomically modern human culture),and explore the uniqueness of human culture.It explores the origin of civilization from the perspective of agricultureand social conflict.展开更多
In the latest years,researchers from the industry and academia extensively applied machine learning algorithms in a broad range of domains.The goal of this special issue is to illustrate the most recent applications o...In the latest years,researchers from the industry and academia extensively applied machine learning algorithms in a broad range of domains.The goal of this special issue is to illustrate the most recent applications of deep learning methods in a range of real-life domains and to show the practical utility of these techniques.A particular attention goes towards methods to process network data that is capable of modelling complex artificial and natural systems as the interactions of a multitude of simpler entities.展开更多
The Third Belt and Road Friendship Football Match between African Embassies and Beijing Schools and China-Africa Sports and Education Forum was held at Beijing No.8 High School,to coincide with the start of the Asian ...The Third Belt and Road Friendship Football Match between African Embassies and Beijing Schools and China-Africa Sports and Education Forum was held at Beijing No.8 High School,to coincide with the start of the Asian Games in Hangzhou on 23 September.The goal of the event,which attracted more than 100 participants,was to encourage cordial Sino-African contacts while promoting collaboration in school sports between China and African nations as part of the Belt and Road Initiative.展开更多
An ultra-wideband pattern reconfigurable antenna is proposed.The antenna is a dielectric coaxial hollow monopole with a cylindrical graphene-based impedance surface coating.It consists of a graphene sheet coated onto ...An ultra-wideband pattern reconfigurable antenna is proposed.The antenna is a dielectric coaxial hollow monopole with a cylindrical graphene-based impedance surface coating.It consists of a graphene sheet coated onto the inner surface of a cylindrical substrate and a set of independent polysilicon DC gating pads mounted on the outside of the cylindrical substrate.By changing the DC bias voltages to the different gating pads,the surface impedance of the graphene coating can be freely controlled.Due to the tunability of graphene＇s surface impedance,the radiation pattern of the proposed antenna can be reconfigured.A transmission line method is used to illustrate the physical mechanism of the proposed antenna.The results show that the proposed antenna can reconfigure its radiation pattern in the omnidirectional mode with the relative bandwidth of 58.5% and the directional mode over the entire azimuth plane with the relative bandwidth of 67%.展开更多
This paper describes the development of a model for unbounded heterogeneous domains with radiation damping produced by an unphysical wave absorbing layer. The Perfectly Matched Layer（PML） approach is used along with...This paper describes the development of a model for unbounded heterogeneous domains with radiation damping produced by an unphysical wave absorbing layer. The Perfectly Matched Layer（PML） approach is used along with a displacement-based finite element. The heterogeneous model is validated using the closed-form solution of a benchmark problem： a free rod with two-part modulus subjected to a specified time history. Both elastically supported and unsupported semi-infinite rods with different degrees of inhomogeneity and loading are considered. Numerical results illustrate the effects of inhomogeneity on the response and are compared with those for equivalent homogeneous domains. The effects of characteristic features of the inhomogeneous problem, presence of local maxima and cut-off frequency are determined. A degenerate case of a homogeneous semi-infinite rod on elastic foundations is produced by tending the magnitude of the foundation stiffness to zero. The response of the latter is compared with that of a free rod. The importance of proper selection of the PML parameters to highly accurate and efficient results is demonstrated by example problems.展开更多
Using the first-principles method based on the density functional theory（DFT）, the work function of seven different Ga N（0001） e1 × 1T surface models is calculated. The calculation results show that the optim...Using the first-principles method based on the density functional theory（DFT）, the work function of seven different Ga N（0001） e1 × 1T surface models is calculated. The calculation results show that the optimal ratio of Cs to O for activation is between 3∶1 and 4∶1. Then, Cs/O activation and stability testing experiments on reflection-mode negative electron affinity Ga N photocathodes are performed. The surface model [Ga N（Mg）： Cs]Cs-O after being activated with cesium and oxygen is used. The experiment results illustrate that the adsorption of O contained in the residual gas increases the surface potential barrier and the reduction of the effective dipole quantity is the basic cause of the quantum efficiency decay.展开更多
This paper is concerned with the existence of adaptive generalized synchronization(GS) of two chaotic systems.An adaptive control is designed based on a Lyapunov approach.By using modified system approach,some suffici...This paper is concerned with the existence of adaptive generalized synchronization(GS) of two chaotic systems.An adaptive control is designed based on a Lyapunov approach.By using modified system approach,some sufficient conditions for the existence of first two types of adaptive GS inertial manifolds are established.Finally,some numerical simulations are provided to illustrate the theoretical results.展开更多
Image registration is an old topic but has a new application in deep-sky imaging fields named live stacking. In this Letter, we propose a live stacking algorithm based on star detection, description, and matching. A t...Image registration is an old topic but has a new application in deep-sky imaging fields named live stacking. In this Letter, we propose a live stacking algorithm based on star detection, description, and matching. A thresholding method based on Otsu and centralization is proposed to implement star detection. Then, a translation and rotation invariant descriptor is proposed to provide accurate feature matching. Extensive experiments illustrate that our proposed method is feasible in deep-sky image live stacking.展开更多
Growth charts describe growth curves at various percentiles that illustrate the distribution of body measurements in children.Over many decades, growth charts have been an invaluable reference for public health worker...Growth charts describe growth curves at various percentiles that illustrate the distribution of body measurements in children.Over many decades, growth charts have been an invaluable reference for public health workers and clinicians to track and evaluate the developmental status of children and to detect abnormal growth for early intervention. Since growth charts were published,they have been greatly detailed in different age, gender, and ethnicity groups.展开更多
Coarse-grained（CG） simulations can more efficiently study large conformational changes of biological polymers but usually lose accuracies in the details. Lots of different hybrid models involving multiple different ...Coarse-grained（CG） simulations can more efficiently study large conformational changes of biological polymers but usually lose accuracies in the details. Lots of different hybrid models involving multiple different resolutions have been developed to overcome the difficulty. Here we propose a novel effective hybrid CG（hyCG） approach which mixes the fine-grained interaction and its average in CG space to form a more smoothing potential energy surface. The hyCG approximately reproduces the potential of mean force in the CG space, and multiple mixed potentials can be further combined together to form a single effective force field for achieving both high efficiency and high accuracy. We illustrate the hyCG method in Trp-cage and Villin headpiece proteins to exhibit the folding of proteins. The topology of the folding landscape and thus the folding paths are preserved, while the folding is boosted nearly one order of magnitude faster. It indicates that the hyCG approach could be applied as an efficient force field in proteins.展开更多
Mixed convection three-dimensional flow of Jeffrey fluid is studied in the presence of thermal radiation and thermophoresis. The relevant problems are formulated,and series solutions are presented for velocities, temp...Mixed convection three-dimensional flow of Jeffrey fluid is studied in the presence of thermal radiation and thermophoresis. The relevant problems are formulated,and series solutions are presented for velocities, temperature, and concentration. Convergence of series solutions is obtained graphically and numerically. Effects of different emerging parameters on the velocities, temperature, and concentration fields are plotted and discussed.展开更多
Life course epidemiology should practically illustrate how risk exposures and their dynamic changes influence the occurrence,development and prognosis of chronic diseases from early life to the elderly.This paper deve...Life course epidemiology should practically illustrate how risk exposures and their dynamic changes influence the occurrence,development and prognosis of chronic diseases from early life to the elderly.This paper develops the lifespan risk exposure measurement instrument（LREMI）in the展开更多
In order to compensate the network-induced random delays in networked control systems（NCSs）, the semi-continuous hidden Markov model（SCHMM） is introduced in this paper to model the controller-to-actuator（CA） del...In order to compensate the network-induced random delays in networked control systems（NCSs）, the semi-continuous hidden Markov model（SCHMM） is introduced in this paper to model the controller-to-actuator（CA） delay in the forward network channel. The expectation maximization algorithm is used to obtain the optimal estimation of the model s parameters, and the Viterbi algorithm is used to predict the CA delay in the current sampling period. Thus, the predicted CA delay and the measured sensor-tocontroller（SC） delay in the current sampling period are used to design an optimal controller. Under this controller, the exponentially mean square stability of the NCS is guaranteed, and the SC and CA delays are compensated. Finally, the effectiveness of the method proposed in this paper is demonstrated by a simulation example. Moreover, a comparative example is also given to illustrate the superiority of the SCHMM-based optimal controller over the discrete hidden Markov model（DHMM）-based optimal controller.展开更多
As the theory of the fractional order differential equation becomes mature gradually, the fractional order neural networks become a new hotspot.The robust stability of a class of fractional order Hopfield neural netwo...As the theory of the fractional order differential equation becomes mature gradually, the fractional order neural networks become a new hotspot.The robust stability of a class of fractional order Hopfield neural network with the Caputo derivative is investigated in this paper. The sufficient conditions to guarantee the robust stability of the fractional order Hopfield neural networks are derived by making use of the property of the Mittag-Leffler function, comparison theorem for the fractional order system, and method of the Laplace integral transform. Furthermore, a numerical simulation example is given to illustrate the correctness and effectiveness of our results.展开更多
Machine learning(ML)techniques have been widely used to address mental health questions.We discuss two main aspects of ML in psychiatry in this paper,that is,supervised learning and unsupervised learning.Examples are ...Machine learning(ML)techniques have been widely used to address mental health questions.We discuss two main aspects of ML in psychiatry in this paper,that is,supervised learning and unsupervised learning.Examples are used to illustrate how ML has been implemented in recent mental health research.展开更多
In the course of researches in certain boundary value problems in hydrodynamics and studying some mathematic-physical problems, one will encounter certain integral equations. If we solve these equations by the convent...In the course of researches in certain boundary value problems in hydrodynamics and studying some mathematic-physical problems, one will encounter certain integral equations. If we solve these equations by the conventional method, we may acquire certain results which disagree with objective reality. Thus it may cause difficulties in describing the inner laws of the corresponding physics. To illustrate what I mean, let us consider the following cases.展开更多
This paper studies the dynamic conducting crack propagation in piezoelectric solids under suddenly in-plane shear loading. Based on the integral transform methods and the Wiener-Hopf technique, the resulting mixed bou...This paper studies the dynamic conducting crack propagation in piezoelectric solids under suddenly in-plane shear loading. Based on the integral transform methods and the Wiener-Hopf technique, the resulting mixed boundary value problem is solved. The analytical solutions of the dynamic stress intensity factor and dynamic electric displacement intensity factor for the Mode II case are derived. Furthermore, the numerical results are presented to illustrate the characteristics of the dynamic crack propagation. It is shown that the universal functions for the dynamic stress and electric displacement intensity factors vanish if the crack propagation speed equals the generalized Rayleigh speed. The results indicate that the defined electro-mechanical coupling coefficient is of great importance to the universal functions and stress intensity factor history.展开更多
基金supported by the National Natural Science Foundation of China(No.61004089)supported by China Scholarship Council
文摘Optimization problems are often highly constrained and evolutionary algorithms（EAs）are effective methods to tackle this kind of problems. To further improve search efficiency and convergence rate of EAs, this paper presents an adaptive double chain quantum genetic algorithm（ADCQGA） for solving constrained optimization problems. ADCQGA makes use of doubleindividuals to represent solutions that are classified as feasible and infeasible solutions. Fitness（or evaluation） functions are defined for both types of solutions. Based on the fitness function, three types of step evolution（SE） are defined and utilized for judging evolutionary individuals. An adaptive rotation is proposed and used to facilitate updating individuals in different solutions.To further improve the search capability and convergence rate, ADCQGA utilizes an adaptive evolution process（AEP）, adaptive mutation and replacement techniques. ADCQGA was first tested on a widely used benchmark function to illustrate the relationship between initial parameter values and the convergence rate/search capability. Then the proposed ADCQGA is successfully applied to solve other twelve benchmark functions and five well-known constrained engineering design problems. Multi-aircraft cooperative target allocation problem is a typical constrained optimization problem and requires efficient methods to tackle. Finally, ADCQGA is successfully applied to solving the target allocation problem.
文摘This book focuses on culture and discusses it from an archaeological perspective.It includes several aspects:to illustrate the uniqueness of the archaeological perspective,introduce the cultural evolution of the Paleolithic Age,especially the birth of cultural modernity(anatomically modern human culture),and explore the uniqueness of human culture.It explores the origin of civilization from the perspective of agricultureand social conflict.
文摘In the latest years,researchers from the industry and academia extensively applied machine learning algorithms in a broad range of domains.The goal of this special issue is to illustrate the most recent applications of deep learning methods in a range of real-life domains and to show the practical utility of these techniques.A particular attention goes towards methods to process network data that is capable of modelling complex artificial and natural systems as the interactions of a multitude of simpler entities.
文摘The Third Belt and Road Friendship Football Match between African Embassies and Beijing Schools and China-Africa Sports and Education Forum was held at Beijing No.8 High School,to coincide with the start of the Asian Games in Hangzhou on 23 September.The goal of the event,which attracted more than 100 participants,was to encourage cordial Sino-African contacts while promoting collaboration in school sports between China and African nations as part of the Belt and Road Initiative.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61661012,61461016,and 61361005)the Natural Science Foundation of Guangxi,China(Grant Nos.2015GXNSFBB139003 and 2014GXNSFAA118283)+1 种基金Program for Innovation Research Team of Guilin University of Electromagnetic Technology,Chinathe Dean Project of Guangxi Key Laboratory of Wireless Wideband Communication and Signal Processing,China
文摘An ultra-wideband pattern reconfigurable antenna is proposed.The antenna is a dielectric coaxial hollow monopole with a cylindrical graphene-based impedance surface coating.It consists of a graphene sheet coated onto the inner surface of a cylindrical substrate and a set of independent polysilicon DC gating pads mounted on the outside of the cylindrical substrate.By changing the DC bias voltages to the different gating pads,the surface impedance of the graphene coating can be freely controlled.Due to the tunability of graphene＇s surface impedance,the radiation pattern of the proposed antenna can be reconfigured.A transmission line method is used to illustrate the physical mechanism of the proposed antenna.The results show that the proposed antenna can reconfigure its radiation pattern in the omnidirectional mode with the relative bandwidth of 58.5% and the directional mode over the entire azimuth plane with the relative bandwidth of 67%.
文摘This paper describes the development of a model for unbounded heterogeneous domains with radiation damping produced by an unphysical wave absorbing layer. The Perfectly Matched Layer（PML） approach is used along with a displacement-based finite element. The heterogeneous model is validated using the closed-form solution of a benchmark problem： a free rod with two-part modulus subjected to a specified time history. Both elastically supported and unsupported semi-infinite rods with different degrees of inhomogeneity and loading are considered. Numerical results illustrate the effects of inhomogeneity on the response and are compared with those for equivalent homogeneous domains. The effects of characteristic features of the inhomogeneous problem, presence of local maxima and cut-off frequency are determined. A degenerate case of a homogeneous semi-infinite rod on elastic foundations is produced by tending the magnitude of the foundation stiffness to zero. The response of the latter is compared with that of a free rod. The importance of proper selection of the PML parameters to highly accurate and efficient results is demonstrated by example problems.
基金supported by the National Natural Science Foundation of China (Nos. 61308089 and 61440065)the Public Technology Applied Research Project of Zhejiang Province (No. 2013C31068)+1 种基金the Applied Research Project of Zhejiang Provincial Education Department (Nos. Y201432598 and 201328587)the China Postdoctoral Science Foundation funded project (No. 2014M551596)
文摘Using the first-principles method based on the density functional theory（DFT）, the work function of seven different Ga N（0001） e1 × 1T surface models is calculated. The calculation results show that the optimal ratio of Cs to O for activation is between 3∶1 and 4∶1. Then, Cs/O activation and stability testing experiments on reflection-mode negative electron affinity Ga N photocathodes are performed. The surface model [Ga N（Mg）： Cs]Cs-O after being activated with cesium and oxygen is used. The experiment results illustrate that the adsorption of O contained in the residual gas increases the surface potential barrier and the reduction of the effective dipole quantity is the basic cause of the quantum efficiency decay.
文摘This paper is concerned with the existence of adaptive generalized synchronization(GS) of two chaotic systems.An adaptive control is designed based on a Lyapunov approach.By using modified system approach,some sufficient conditions for the existence of first two types of adaptive GS inertial manifolds are established.Finally,some numerical simulations are provided to illustrate the theoretical results.
文摘Image registration is an old topic but has a new application in deep-sky imaging fields named live stacking. In this Letter, we propose a live stacking algorithm based on star detection, description, and matching. A thresholding method based on Otsu and centralization is proposed to implement star detection. Then, a translation and rotation invariant descriptor is proposed to provide accurate feature matching. Extensive experiments illustrate that our proposed method is feasible in deep-sky image live stacking.
文摘Growth charts describe growth curves at various percentiles that illustrate the distribution of body measurements in children.Over many decades, growth charts have been an invaluable reference for public health workers and clinicians to track and evaluate the developmental status of children and to detect abnormal growth for early intervention. Since growth charts were published,they have been greatly detailed in different age, gender, and ethnicity groups.
基金Project supported by the National Basic Research Program of China(Grant No.2013CB932803)the National Natural Science Foundation of China(Grant No.11574310)+2 种基金the Joint NSFC-ISF Research Programjointly funded by the National Natural Science Foundation of Chinathe Israel Science Foundation(Grant No.51561145002)
文摘Coarse-grained（CG） simulations can more efficiently study large conformational changes of biological polymers but usually lose accuracies in the details. Lots of different hybrid models involving multiple different resolutions have been developed to overcome the difficulty. Here we propose a novel effective hybrid CG（hyCG） approach which mixes the fine-grained interaction and its average in CG space to form a more smoothing potential energy surface. The hyCG approximately reproduces the potential of mean force in the CG space, and multiple mixed potentials can be further combined together to form a single effective force field for achieving both high efficiency and high accuracy. We illustrate the hyCG method in Trp-cage and Villin headpiece proteins to exhibit the folding of proteins. The topology of the folding landscape and thus the folding paths are preserved, while the folding is boosted nearly one order of magnitude faster. It indicates that the hyCG approach could be applied as an efficient force field in proteins.
基金Project supported by the Deanship of Scientific Research(DSR)of King Abdulaziz University in Jeddah(No.26-130-35-HiCi)
文摘Mixed convection three-dimensional flow of Jeffrey fluid is studied in the presence of thermal radiation and thermophoresis. The relevant problems are formulated,and series solutions are presented for velocities, temperature, and concentration. Convergence of series solutions is obtained graphically and numerically. Effects of different emerging parameters on the velocities, temperature, and concentration fields are plotted and discussed.
基金supported by grants from the National Natural Science Foundation of China[81273177]the Science and Technology Development Planning of Shandong Province[2014GSF118119]
文摘Life course epidemiology should practically illustrate how risk exposures and their dynamic changes influence the occurrence,development and prognosis of chronic diseases from early life to the elderly.This paper develops the lifespan risk exposure measurement instrument（LREMI）in the
基金supported by National Natural Science Foundation of China(No S.61203034 and 61572032)
文摘In order to compensate the network-induced random delays in networked control systems（NCSs）, the semi-continuous hidden Markov model（SCHMM） is introduced in this paper to model the controller-to-actuator（CA） delay in the forward network channel. The expectation maximization algorithm is used to obtain the optimal estimation of the model s parameters, and the Viterbi algorithm is used to predict the CA delay in the current sampling period. Thus, the predicted CA delay and the measured sensor-tocontroller（SC） delay in the current sampling period are used to design an optimal controller. Under this controller, the exponentially mean square stability of the NCS is guaranteed, and the SC and CA delays are compensated. Finally, the effectiveness of the method proposed in this paper is demonstrated by a simulation example. Moreover, a comparative example is also given to illustrate the superiority of the SCHMM-based optimal controller over the discrete hidden Markov model（DHMM）-based optimal controller.
基金supported by the Natural Science Foundation of Shandong Province under Grant No.ZR2014AM006
文摘As the theory of the fractional order differential equation becomes mature gradually, the fractional order neural networks become a new hotspot.The robust stability of a class of fractional order Hopfield neural network with the Caputo derivative is investigated in this paper. The sufficient conditions to guarantee the robust stability of the fractional order Hopfield neural networks are derived by making use of the property of the Mittag-Leffler function, comparison theorem for the fractional order system, and method of the Laplace integral transform. Furthermore, a numerical simulation example is given to illustrate the correctness and effectiveness of our results.
文摘Machine learning(ML)techniques have been widely used to address mental health questions.We discuss two main aspects of ML in psychiatry in this paper,that is,supervised learning and unsupervised learning.Examples are used to illustrate how ML has been implemented in recent mental health research.
文摘In the course of researches in certain boundary value problems in hydrodynamics and studying some mathematic-physical problems, one will encounter certain integral equations. If we solve these equations by the conventional method, we may acquire certain results which disagree with objective reality. Thus it may cause difficulties in describing the inner laws of the corresponding physics. To illustrate what I mean, let us consider the following cases.
基金supported by the National Natural Science Foundation of China(Grant Nos.11302260,11090330,11090331,11072003 and 11272222)the National Basic Research Program of China(Grant No.G2010CB832701)
文摘This paper studies the dynamic conducting crack propagation in piezoelectric solids under suddenly in-plane shear loading. Based on the integral transform methods and the Wiener-Hopf technique, the resulting mixed boundary value problem is solved. The analytical solutions of the dynamic stress intensity factor and dynamic electric displacement intensity factor for the Mode II case are derived. Furthermore, the numerical results are presented to illustrate the characteristics of the dynamic crack propagation. It is shown that the universal functions for the dynamic stress and electric displacement intensity factors vanish if the crack propagation speed equals the generalized Rayleigh speed. The results indicate that the defined electro-mechanical coupling coefficient is of great importance to the universal functions and stress intensity factor history.
