Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,te...Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,termed traveling-wave based time embedding,utilized as a pseudo channel to enhance the decoding accuracy of MI-EEG signals across various neural network architectures.Unlike traditional neural network methods that fail to account for the temporal dynamics in MI-EEG in individual difference,our approach captures time-related changes for different participants based on a priori knowledge.Through extensive experimentation with multiple participants,we demonstrate that this method not only improves classification accuracy but also exhibits greater adaptability to individual differences compared to position encoding used in Transformer architecture.Significantly,our results reveal that traveling-wave based time embedding crucially enhances decoding accuracy,particularly for participants typically considered“EEG-illiteracy”.As a novel direction in EEG research,the traveling-wave based time embedding not only offers fresh insights for neural network decoding strategies but also expands new avenues for research into attention mechanisms in neuroscience and a deeper understanding of EEG signals.展开更多
Based on the conflict graph model which is formulated as a binary integer optimization problem, a resource allocation method to support device-to-device (D2D) communications in ceUular networks is proposed. First, a...Based on the conflict graph model which is formulated as a binary integer optimization problem, a resource allocation method to support device-to-device (D2D) communications in ceUular networks is proposed. First, a frequency resource assignment algorithm is presented which assigns each D2D link one frequency resource block. For this algorithm, frequency resource blocks are assigned so that the frequency resource spatial reuse opportunities in the cellular networks can be fully exploited. Then a slot scheduling algorithm is presented which schedules time slots among D2D links assigned the same frequency resource block. For this algorithm, time slot resources are scheduled so that the proportional fairness among D2D links which are assigned the same frequency resource block can be achieved. The performance of the proposed method is evaluated via computer simulations. The simulation results show that the proposed method can well support D2D communications in cellular networks.展开更多
The security problem of the Web system in the Internet based Intranet and the shortcomings of the methods used in solving this problem are analyzed and our system model of Web communication security are discussed, i...The security problem of the Web system in the Internet based Intranet and the shortcomings of the methods used in solving this problem are analyzed and our system model of Web communication security are discussed, i.e, adding local proxy to browser and reverse proxy to Web server based on present Web browser and server. The transformation between HTTP message and secure HTTP message is implemented in these two proxy modules. The architecture and implementing method is given and the features of this module is also discussed.展开更多
To cope with the constraint problem of power consumption and transmission delay in the virtual backbone of wireless sensor network, a distributed connected dominating set (CDS) algorithm with (α,β)-constraints i...To cope with the constraint problem of power consumption and transmission delay in the virtual backbone of wireless sensor network, a distributed connected dominating set (CDS) algorithm with (α,β)-constraints is proposed. Based on the (α, β)-tree concept, a new connected dominating tree with bounded transmission delay problem(CDTT) is defined and a corresponding algorithm is designed to construct a CDT-tree which can trade off limited total power and bounded transmission delay from source to destination nodes. The CDT algorithm consists of two phases: The first phase constructs a maximum independent set(MIS)in a unit disk graph model. The second phase estimates the distance and calculates the transmission power to construct a spanning tree in an undirected graph with different weights for MST and SPF, respectively. The theoretical analysis and simulation results show that the CDT algorithm gives a correct solution to the CDTF problem and forms a virtual backbone with( α,β)-constraints balancing the requirements of power consumption and transmission delay.展开更多
The performance of the graph-based scheduling for device-to-device communications overlaying cellular networks is studied. The graph-based scheduling consists of two stages, the frequency assignment stage and the time...The performance of the graph-based scheduling for device-to-device communications overlaying cellular networks is studied. The graph-based scheduling consists of two stages, the frequency assignment stage and the time slot scheduling stage. For such scheduling, a theoretical method to analyze the average spectrum efficiency of the D2D subsystem is proposed. The method consists of three steps. First, the frequency assignment stage is analyzed and the approximate formula of the average number of the D2D links which are assigned the same frequency is derived. Secondly, the time slot scheduling stage is analyzed and the approximate formula of the average probability of a D2D link being scheduled in a time slot is derived. Thirdly, the average spectrum efficiency of the D2D subsystem is analyzed and the corresponding approximate formula is derived. Analysis results show that the average spectrum efficiency of the D2D subsystem is approximately inversely linearly proportional to the second- order origin moment of the normalized broadcast radius of D2D links. Simulation results show that the proposed method can correctly predict the average spectrum efficiency of the D2D subsystem.展开更多
Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) d...Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) discontinuities. Modeled discontinuities include : CPW step, interdigital capacitor, symmetric cross junction, and spiral inductor, for which validation tests are performed. These models allow for circuit design, simulation, and optimization within a CAD simulator. Design and realization of a coplanar lumped element band pass filter on GaAs using the developed CPW EC-ANN models are demonstrated.展开更多
The virtual private network (VPN) system, which is one of the construction methods for private networks over the Internet, is gaining prominence. VPNs are currently used for corporate networks to support end to end ...The virtual private network (VPN) system, which is one of the construction methods for private networks over the Internet, is gaining prominence. VPNs are currently used for corporate networks to support end to end communications. But if they are applied to private networks for distributed departments in organizations, some problems should be concerned, such as low efficiency of packet transfer and nonsupport of unsymmetrical VPN connections. At first this paper analyzes the limitations of VPN used in the environment of multiple subnets, and then brings up a distributed module of VPN with low cost, high packet transfer efficiency and powerful functions of user authentication and access control.展开更多
In order to improve network connectivity in clustered wireless sensor networks,a node cooperative algorithm based on virtual antenna arrays is proposed.All the nodes in the network are assumed to be clustered via Pois...In order to improve network connectivity in clustered wireless sensor networks,a node cooperative algorithm based on virtual antenna arrays is proposed.All the nodes in the network are assumed to be clustered via Poisson Voronoi tessellation(PVT).The activation of the node cooperative algorithm is determined by the cluster heads(CHs) according to communication links.When the cooperative algorithm is activated,the CH selects cooperative nodes(CNs) from its members to form a virtual antenna array.With the cooperation,nodes can extend the inter-cluster communication range to directly contact with further nodes after a coverage hole is detected,or compensate for channel gains while inter-cluster transmission fails due to deep channel fading.Simulation results show that the proposed algorithm achieves better network connectivity and energy efficiency.It can reduce outage probability,sustain network connectivity and maintain operations as long as possible,which prolongs network operation time.展开更多
The concept of intelligent integrated network management (IINM) is briefly introduced. In order to analyze, design and implement IINM successfully, object oriented approach is testified to be an effective and efficien...The concept of intelligent integrated network management (IINM) is briefly introduced. In order to analyze, design and implement IINM successfully, object oriented approach is testified to be an effective and efficient way. In this paper, object oriented technique is applied to the structural model of IINM system, The Domain object class and the MU object class are used to represent the manager and the managed resources. Especially, NM IA is introduced which is a special object class with intelligent behaviors to manage the resources efficiently.展开更多
Aim To determine the global optimal solution for a mine ventilation network under given network topology and airway characteristics. Methods\ The genetic algorithm was used to find the global optimal solution of the ...Aim To determine the global optimal solution for a mine ventilation network under given network topology and airway characteristics. Methods\ The genetic algorithm was used to find the global optimal solution of the network. Results\ A modified genetic algorithm is presented with its characteristics and principle. Instead of working on the conventional bit by bit operation, both the crossover and mutation operators are handled in real values by the proposed algorithms. To prevent the system from turning into a premature problem, the elitists from two groups of possible solutions are selected to reproduce the new populations. Conclusion\ The simulation results show that the method outperforms the conventional nonlinear programming approach whether from the viewpoint of the number of iterations required to find the optimum solutions or from the final solutions obtained.展开更多
Aimed at the difficulties in accurately, comprehensively and systematically evaluating the reliability of industrial wireless sensor networks (WSNs), a time-evolving state transition-Monte Carlo (TEST-MC) evaluati...Aimed at the difficulties in accurately, comprehensively and systematically evaluating the reliability of industrial wireless sensor networks (WSNs), a time-evolving state transition-Monte Carlo (TEST-MC) evaluation method and a novel network function value representation method are proposed to evaluate the reliability of the IWSNs. First, the adjacency matrix method is used to characterize three typical topologies of WSNs including the mesh network, tree network and ribbon network. Secondly, the network function value method is used to evaluate the network connectivity, and the TEST-MC evaluation method is used to evaluate network reliability and availability. Finally, the variations in the reliability, connectivity and availability of these three topologies are presented. Simulation results show that the proposed method can quickly analyze the reliability of the networks containing typical WSN topologies, which provides an effective method for the comprehensive and accurate evaluation of the reliability of WSNs.展开更多
With ensured network connectivity in quantum channels, the issue of distributing entangled particles in wireless quantum communication mesh networks can be equivalently regarded as a problem of quantum backbone nodes ...With ensured network connectivity in quantum channels, the issue of distributing entangled particles in wireless quantum communication mesh networks can be equivalently regarded as a problem of quantum backbone nodes selection in order to save cost and reduce complexity. A minimum spanning tree( MST)-based quantum distribution algorithm( QDMST) is presented to construct the mesh backbone network. First, the articulation points are found,and for each connected block uncovered by the articulation points, the general centers are solved. Then, both articulation points and general centers are classified as backbone nodes and an M ST is formed. The quantum path between every two neighbor nodes on the MST is calculated. The nodes on these paths are also classified as backbone nodes. Simulation results validate the advantages of QDMST in the average backbone nodes number and average quantum channel distance compared to the existing random selection algorithm under multiple network scenarios.展开更多
The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagg...The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagging of the signal timing plans to traffic conditions. Utilizing the traffic conditions in current and former intervals, the network topology of the state-space neural network (SSNN), which is derived from the geometry of urban arterial routes, is used to predict the optimal timing plan corresponding to the traffic conditions in the next time interval. In order to improve the effectiveness of the SSNN, the extended Kalman filter (EKF) is proposed to train the SSNN instead of conventional approaches. Raw traffic data of the Guangzhou Road, Nanjing and the optimal signal timing plan generated by a multi-objective optimization genetic algorithm are applied to test the performance of the proposed model. The results indicate that compared with the SSNN and the BP neural network, the proposed model can closely match the optimal timing plans in futuristic states with higher efficiency.展开更多
The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users' choices of trip paths, are a...The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users' choices of trip paths, are analyzed. Travelers usually decide their trip paths based on their personal habits, preferences and the information at hand. By considering both deterministic and stochastic factors which affect the value of time (VOT) during the process of path choosing, a variational inequality model is proposed to describe the problem of traffic assignment. A lazy loading algorithm for traffic assignment is designed to solve the proposed model, and the calculation steps are given. Numerical experiment results show that compared with the all-or-nothing assignment, the proposed model and the algorithm can provide more optimal traffic assignments for road networks. The results of this study can be used to optimize traffic planning and management.展开更多
文摘Motor imagery(MI)based electroencephalogram(EEG)represents a frontier in enabling direct neural control of external devices and advancing neural rehabilitation.This study introduces a novel time embedding technique,termed traveling-wave based time embedding,utilized as a pseudo channel to enhance the decoding accuracy of MI-EEG signals across various neural network architectures.Unlike traditional neural network methods that fail to account for the temporal dynamics in MI-EEG in individual difference,our approach captures time-related changes for different participants based on a priori knowledge.Through extensive experimentation with multiple participants,we demonstrate that this method not only improves classification accuracy but also exhibits greater adaptability to individual differences compared to position encoding used in Transformer architecture.Significantly,our results reveal that traveling-wave based time embedding crucially enhances decoding accuracy,particularly for participants typically considered“EEG-illiteracy”.As a novel direction in EEG research,the traveling-wave based time embedding not only offers fresh insights for neural network decoding strategies but also expands new avenues for research into attention mechanisms in neuroscience and a deeper understanding of EEG signals.
基金The National High Technology Research and Development Program of China(863 Program)(No.SS2014AA012103)the National Natural Science Foundation of China(No.61001103)
文摘Based on the conflict graph model which is formulated as a binary integer optimization problem, a resource allocation method to support device-to-device (D2D) communications in ceUular networks is proposed. First, a frequency resource assignment algorithm is presented which assigns each D2D link one frequency resource block. For this algorithm, frequency resource blocks are assigned so that the frequency resource spatial reuse opportunities in the cellular networks can be fully exploited. Then a slot scheduling algorithm is presented which schedules time slots among D2D links assigned the same frequency resource block. For this algorithm, time slot resources are scheduled so that the proportional fairness among D2D links which are assigned the same frequency resource block can be achieved. The performance of the proposed method is evaluated via computer simulations. The simulation results show that the proposed method can well support D2D communications in cellular networks.
文摘The security problem of the Web system in the Internet based Intranet and the shortcomings of the methods used in solving this problem are analyzed and our system model of Web communication security are discussed, i.e, adding local proxy to browser and reverse proxy to Web server based on present Web browser and server. The transformation between HTTP message and secure HTTP message is implemented in these two proxy modules. The architecture and implementing method is given and the features of this module is also discussed.
基金Major Program of the National Natural Science Foundation of China (No.70533050)High Technology Research Program ofJiangsu Province(No.BG2007012)+1 种基金China Postdoctoral Science Foundation(No.20070411065)Science Foundation of China University of Mining andTechnology(No.OC080303)
文摘To cope with the constraint problem of power consumption and transmission delay in the virtual backbone of wireless sensor network, a distributed connected dominating set (CDS) algorithm with (α,β)-constraints is proposed. Based on the (α, β)-tree concept, a new connected dominating tree with bounded transmission delay problem(CDTT) is defined and a corresponding algorithm is designed to construct a CDT-tree which can trade off limited total power and bounded transmission delay from source to destination nodes. The CDT algorithm consists of two phases: The first phase constructs a maximum independent set(MIS)in a unit disk graph model. The second phase estimates the distance and calculates the transmission power to construct a spanning tree in an undirected graph with different weights for MST and SPF, respectively. The theoretical analysis and simulation results show that the CDT algorithm gives a correct solution to the CDTF problem and forms a virtual backbone with( α,β)-constraints balancing the requirements of power consumption and transmission delay.
基金The National Natural Science Foundation of China(No.61571111)the National High Technology Research and Development Program of China(863 Program)(No.2014AA01A703,2015AA01A706)the Fundamental Research Funds for the Central Universities of China(No.2242016K40098)
文摘The performance of the graph-based scheduling for device-to-device communications overlaying cellular networks is studied. The graph-based scheduling consists of two stages, the frequency assignment stage and the time slot scheduling stage. For such scheduling, a theoretical method to analyze the average spectrum efficiency of the D2D subsystem is proposed. The method consists of three steps. First, the frequency assignment stage is analyzed and the approximate formula of the average number of the D2D links which are assigned the same frequency is derived. Secondly, the time slot scheduling stage is analyzed and the approximate formula of the average probability of a D2D link being scheduled in a time slot is derived. Thirdly, the average spectrum efficiency of the D2D subsystem is analyzed and the corresponding approximate formula is derived. Analysis results show that the average spectrum efficiency of the D2D subsystem is approximately inversely linearly proportional to the second- order origin moment of the normalized broadcast radius of D2D links. Simulation results show that the proposed method can correctly predict the average spectrum efficiency of the D2D subsystem.
文摘Novel accurate and efficient equivalent circuit trained artificial neural-network (EC-ANN) models,which inherit and improve upon EC model and EM-ANN models' advantages,are developed for coplanar waveguide (CPW) discontinuities. Modeled discontinuities include : CPW step, interdigital capacitor, symmetric cross junction, and spiral inductor, for which validation tests are performed. These models allow for circuit design, simulation, and optimization within a CAD simulator. Design and realization of a coplanar lumped element band pass filter on GaAs using the developed CPW EC-ANN models are demonstrated.
文摘The virtual private network (VPN) system, which is one of the construction methods for private networks over the Internet, is gaining prominence. VPNs are currently used for corporate networks to support end to end communications. But if they are applied to private networks for distributed departments in organizations, some problems should be concerned, such as low efficiency of packet transfer and nonsupport of unsymmetrical VPN connections. At first this paper analyzes the limitations of VPN used in the environment of multiple subnets, and then brings up a distributed module of VPN with low cost, high packet transfer efficiency and powerful functions of user authentication and access control.
基金The National Natural Science Foundation of China ( No.60872004, 60972026)the Important National Science and Technology Specific Projects (No. 2010ZX03006-002-01)the Research Fund of the National Mobile Communications Research Laboratory of Southeast University (No.2010A08)
文摘In order to improve network connectivity in clustered wireless sensor networks,a node cooperative algorithm based on virtual antenna arrays is proposed.All the nodes in the network are assumed to be clustered via Poisson Voronoi tessellation(PVT).The activation of the node cooperative algorithm is determined by the cluster heads(CHs) according to communication links.When the cooperative algorithm is activated,the CH selects cooperative nodes(CNs) from its members to form a virtual antenna array.With the cooperation,nodes can extend the inter-cluster communication range to directly contact with further nodes after a coverage hole is detected,or compensate for channel gains while inter-cluster transmission fails due to deep channel fading.Simulation results show that the proposed algorithm achieves better network connectivity and energy efficiency.It can reduce outage probability,sustain network connectivity and maintain operations as long as possible,which prolongs network operation time.
文摘The concept of intelligent integrated network management (IINM) is briefly introduced. In order to analyze, design and implement IINM successfully, object oriented approach is testified to be an effective and efficient way. In this paper, object oriented technique is applied to the structural model of IINM system, The Domain object class and the MU object class are used to represent the manager and the managed resources. Especially, NM IA is introduced which is a special object class with intelligent behaviors to manage the resources efficiently.
文摘Aim To determine the global optimal solution for a mine ventilation network under given network topology and airway characteristics. Methods\ The genetic algorithm was used to find the global optimal solution of the network. Results\ A modified genetic algorithm is presented with its characteristics and principle. Instead of working on the conventional bit by bit operation, both the crossover and mutation operators are handled in real values by the proposed algorithms. To prevent the system from turning into a premature problem, the elitists from two groups of possible solutions are selected to reproduce the new populations. Conclusion\ The simulation results show that the method outperforms the conventional nonlinear programming approach whether from the viewpoint of the number of iterations required to find the optimum solutions or from the final solutions obtained.
基金The International S&T Cooperation Program of China(No.2015DFA10490)the National Natural Science Foundation of China(No.61571113,61240032)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20130092110060)
文摘Aimed at the difficulties in accurately, comprehensively and systematically evaluating the reliability of industrial wireless sensor networks (WSNs), a time-evolving state transition-Monte Carlo (TEST-MC) evaluation method and a novel network function value representation method are proposed to evaluate the reliability of the IWSNs. First, the adjacency matrix method is used to characterize three typical topologies of WSNs including the mesh network, tree network and ribbon network. Secondly, the network function value method is used to evaluate the network connectivity, and the TEST-MC evaluation method is used to evaluate network reliability and availability. Finally, the variations in the reliability, connectivity and availability of these three topologies are presented. Simulation results show that the proposed method can quickly analyze the reliability of the networks containing typical WSN topologies, which provides an effective method for the comprehensive and accurate evaluation of the reliability of WSNs.
基金Prospective Research Project on Future Networks of Jiangsu Province,China(No.BY2013095-1-18)
文摘With ensured network connectivity in quantum channels, the issue of distributing entangled particles in wireless quantum communication mesh networks can be equivalently regarded as a problem of quantum backbone nodes selection in order to save cost and reduce complexity. A minimum spanning tree( MST)-based quantum distribution algorithm( QDMST) is presented to construct the mesh backbone network. First, the articulation points are found,and for each connected block uncovered by the articulation points, the general centers are solved. Then, both articulation points and general centers are classified as backbone nodes and an M ST is formed. The quantum path between every two neighbor nodes on the MST is calculated. The nodes on these paths are also classified as backbone nodes. Simulation results validate the advantages of QDMST in the average backbone nodes number and average quantum channel distance compared to the existing random selection algorithm under multiple network scenarios.
基金The National Natural Science Foundation of China (No.50422283)the Soft Science Research Project of Ministry of Housing and Urban-Rural Development of China (No.2008-K5-14)
文摘The state-space neural network and extended Kalman filter model is used to directly predict the optimal timing plan that corresponds to futuristic traffic conditions in real time with the purposes of avoiding the lagging of the signal timing plans to traffic conditions. Utilizing the traffic conditions in current and former intervals, the network topology of the state-space neural network (SSNN), which is derived from the geometry of urban arterial routes, is used to predict the optimal timing plan corresponding to the traffic conditions in the next time interval. In order to improve the effectiveness of the SSNN, the extended Kalman filter (EKF) is proposed to train the SSNN instead of conventional approaches. Raw traffic data of the Guangzhou Road, Nanjing and the optimal signal timing plan generated by a multi-objective optimization genetic algorithm are applied to test the performance of the proposed model. The results indicate that compared with the SSNN and the BP neural network, the proposed model can closely match the optimal timing plans in futuristic states with higher efficiency.
基金The National High Technology Research and Development Program of China(863 Program)(No.2007AA11Z202)the National Key Technology R&D Program of China during the 11th Five-Year Plan Period(No.2006BAJ18B03)
文摘The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users' choices of trip paths, are analyzed. Travelers usually decide their trip paths based on their personal habits, preferences and the information at hand. By considering both deterministic and stochastic factors which affect the value of time (VOT) during the process of path choosing, a variational inequality model is proposed to describe the problem of traffic assignment. A lazy loading algorithm for traffic assignment is designed to solve the proposed model, and the calculation steps are given. Numerical experiment results show that compared with the all-or-nothing assignment, the proposed model and the algorithm can provide more optimal traffic assignments for road networks. The results of this study can be used to optimize traffic planning and management.