At present,the database cache model of power information system has problems such as slow running speed and low database hit rate.To this end,this paper proposes a database cache model for power information systems ba...At present,the database cache model of power information system has problems such as slow running speed and low database hit rate.To this end,this paper proposes a database cache model for power information systems based on deep machine learning.The caching model includes program caching,Structured Query Language(SQL)preprocessing,and core caching modules.Among them,the method to improve the efficiency of the statement is to adjust operations such as multi-table joins and replacement keywords in the SQL optimizer.Build predictive models using boosted regression trees in the core caching module.Generate a series of regression tree models using machine learning algorithms.Analyze the resource occupancy rate in the power information system to dynamically adjust the voting selection of the regression tree.At the same time,the voting threshold of the prediction model is dynamically adjusted.By analogy,the cache model is re-initialized.The experimental results show that the model has a good cache hit rate and cache efficiency,and can improve the data cache performance of the power information system.It has a high hit rate and short delay time,and always maintains a good hit rate even under different computer memory;at the same time,it only occupies less space and less CPU during actual operation,which is beneficial to power The information system operates efficiently and quickly.展开更多
Wireless information and power transfer(WIPT) enables simultaneously communications and sustainable power supplement without the erection of power supply lines and the replacement operation of the batteries for the te...Wireless information and power transfer(WIPT) enables simultaneously communications and sustainable power supplement without the erection of power supply lines and the replacement operation of the batteries for the terminals. The application of WIPT to the underwater acoustic sensor networks(UWASNs) not only retains the long range communication capabilities, but also provides an auxiliary and convenient energy supplement way for the terminal sensors, and thus is a promising scheme to solve the energy-limited problem for the UWASNs. In this paper, we propose the integration of WIPT into the UWASNs and provide an overview on various enabling techniques for the WIPT based UWASNs(WIPT-UWASNs) as well as pointing out future research challenges and opportunities for WIPT-UWASNs.展开更多
Applications using simultaneous wireless information and power transfer(SWIPT)have increased significantly.Wireless communication technologies can be combined with the Internet of Things to develop many innovative app...Applications using simultaneous wireless information and power transfer(SWIPT)have increased significantly.Wireless communication technologies can be combined with the Internet of Things to develop many innovative applications using SWIPT,which is mainly based on wireless energy harvesting from electromagnetic waves used in communications.Wireless power transfer that uses magnetrons has been developed for communication technologies.Injection-locked magnetrons that can be used to facilitate high-power SWIPT for several devices are reviewed in this paper.This new technology is expected to pave the way for promoting the application of SWIPT in a wide range of fields.展开更多
Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network....Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network. However, Simultaneous Wireless Information and Power Transfer (SWIPT) in the same RF bands is challenging. The majority of previous studies compared SWIPT performance to Gaussian signaling with an infinite alphabet, which is impossible to implement in any realistic communication system. In contrast, we study the SWIPT system in a well-known Nakagami-m wireless fading channel using practical modulation techniques with finite alphabet. The attainable rate-energy-reliability tradeoff and the corresponding rationale are revealed for fixed modulation schemes. Furthermore, an adaptive modulation-based transceiver is provided for further expanding the attainable rate-energy-reliability region based on various SWIPT performances of different modulation schemes. The modulation switching thresholds and transmit power allocation at the SWIPT transmitter and the power splitting ratios at the SWIPT receiver are jointly optimized to maximize the attainable spectrum efficiency of wireless information transfer while satisfying the WPT requirement and the instantaneous and average BER constraints. Numerical results demonstrate the SWIPT performance of various fixed modulation schemes in different fading conditions. The advantage of the adaptive modulation-based SWIPT transceiver is validated.展开更多
Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous...Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous wireless information and power transfers(SWIPT),offering an optimized wireless energy management network.Both transmitting and receiving sides of the proposed solution are presented in detail.On the transmitting side,employing the wireless power transfer(WPT)technique,we present versatile power conveying strategies for near-field or far-field targets,single or multiple targets,and equal or unequal power targets.On the receiving side,utilizing the wireless energy harvesting(WEH)technique,we report our work on multi-functional rectifying metasurfaces that collect the wirelessly transmitted energy and the ambient energy.More importantly,a numerical model based on the plane-wave angular spectrum method is investigated to accurately calculate the radiation fields of PMS in the Fresnel and Fraunhofer regions.With this model,the efficiencies of WPT between the transmitter and the receiver are analyzed.Finally,future research directions are discussed,and integrated PMS for wireless information and wireless power is outlined.展开更多
Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Ra...Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Rayleigh fading channel.A novel EE that is defined as the average transmission rate divided by the total consumed power is introduced.In accordance with this definition,an adaptive power allocation(PA) scheme for DAS is proposed to maximize the EE under the maximum transmit power constraint.The solution of PA in the constrained EE optimization does exist and is unique.A practical iterative algorithm with Newton method is presented to obtain the solution of PA.The proposed scheme includes the one under perfect CSI as a special case,and it only needs large scale and statistical information.As a result,the scheme has low overhead and good robustness.The theoretical EE is also derived for performance evaluation,and simulation result shows the validity of the theoretical analysis.Moreover,EE can be enhanced by decreasing the estimation error and/or path loss exponents.展开更多
Direct electrical stimulation of the human cortex can produce subjective visual sensations,yet these sensations are unstable.The underlying mechanisms may stem from differences in electrophysiological activity within ...Direct electrical stimulation of the human cortex can produce subjective visual sensations,yet these sensations are unstable.The underlying mechanisms may stem from differences in electrophysiological activity within the distributed network outside the stimulated site.To address this problem,we recruited 69 patients who experienced visual sensations during invasive electrical stimulation while intracranial electroencephalography(iEEG)data were recorded.We found significantly flattened power spectral slopes in distributed regions involving different brain networks and decreased integrated information during elicited visual sensations compared with the non-sensation condition.Further analysis based on minimum information partitions revealed that the reconfigured network interactions primarily involved the inferior frontal cortex,posterior superior temporal sulcus,and temporoparietal junction.The flattened power spectral slope in the inferior frontal gyrus was also correlated with integrated information.Taken together,this study indicates that the altered electrophysiological signatures provide insights into the neural mechanisms underlying subjective visual sensations.展开更多
The performance of traditional regular Intelligent Reflecting Surface(IRS)improves as the number of IRS elements increases,but more reflecting elements lead to higher IRS power consumption and greater overhead of chan...The performance of traditional regular Intelligent Reflecting Surface(IRS)improves as the number of IRS elements increases,but more reflecting elements lead to higher IRS power consumption and greater overhead of channel estimation.The Irregular Intelligent Reflecting Surface(IIRS)can enhance the performance of the IRS as well as boost the system performance when the number of reflecting elements is limited.However,due to the lack of radio frequency chain in IRS,it is challenging for the Base Station(BS)to gather perfect Channel State Information(CSI),especially in the presence of Eavesdroppers(Eves).Therefore,in this paper we investigate the minimum transmit power problem of IIRS-aided Simultaneous Wireless Information and Power Transfer(SWIPT)secure communication system with imperfect CSI of BS-IIRS-Eves links,which is subject to the rate outage probability constraints of the Eves,the minimum rate constraints of the Information Receivers(IRs),the energy harvesting constraints of the Energy Receivers(ERs),and the topology matrix constraints.Afterward,the formulated nonconvex problem can be efficiently tackled by employing joint optimization algorithm combined with successive refinement method and adaptive topology design method.Simulation results demonstrate the effectiveness of the proposed scheme and the superiority of IIRS.展开更多
In the Internet of Things(IoT)based scenarios,the network may encounter significant issues related to energy and communication as a result of a progressively growing number of terminals.We introduce simultaneous wirel...In the Internet of Things(IoT)based scenarios,the network may encounter significant issues related to energy and communication as a result of a progressively growing number of terminals.We introduce simultaneous wireless power transfer(SWIPT)technology assisted by a reconfigurable intelligent surface(RIS)to counteract this challenge.Thus,the network’s flexibility and reliability will be further enhanced.According to this system architecture,the scattering-parameter-based communication model is introduced to disclose hardware features for an energy efficiency(EE)maximization problem.Specifically,the potential unauthorized demodulation is also considered in the problem formulation.To resolve the issue,an alternative strategy is utilized to optimize iteratively the coupled variables.In particular,the block coordinate descent(BCD)approach based on the Sherman-Morrison formula is proposed to solve the RIS subproblem.The numerical results prove the hardware effects cannot be dismissed lightly.Besides,the configuration of the RIS may impact the network performance directly.展开更多
文摘At present,the database cache model of power information system has problems such as slow running speed and low database hit rate.To this end,this paper proposes a database cache model for power information systems based on deep machine learning.The caching model includes program caching,Structured Query Language(SQL)preprocessing,and core caching modules.Among them,the method to improve the efficiency of the statement is to adjust operations such as multi-table joins and replacement keywords in the SQL optimizer.Build predictive models using boosted regression trees in the core caching module.Generate a series of regression tree models using machine learning algorithms.Analyze the resource occupancy rate in the power information system to dynamically adjust the voting selection of the regression tree.At the same time,the voting threshold of the prediction model is dynamically adjusted.By analogy,the cache model is re-initialized.The experimental results show that the model has a good cache hit rate and cache efficiency,and can improve the data cache performance of the power information system.It has a high hit rate and short delay time,and always maintains a good hit rate even under different computer memory;at the same time,it only occupies less space and less CPU during actual operation,which is beneficial to power The information system operates efficiently and quickly.
基金supported in part by the National Natural Science Foundation of China under Grant 62171187the Guangdong Basic and Applied Basic Research Foundation under Grant 2022A1515011476+1 种基金the Science and Technology Program of Guangzhou under Grant 201904010373the Key Program of Marine Economy Development (Six Marine Industries) Special Foundation of Department of Natural Resources of Guangdong Province (GDNRC [2020]009)。
文摘Wireless information and power transfer(WIPT) enables simultaneously communications and sustainable power supplement without the erection of power supply lines and the replacement operation of the batteries for the terminals. The application of WIPT to the underwater acoustic sensor networks(UWASNs) not only retains the long range communication capabilities, but also provides an auxiliary and convenient energy supplement way for the terminal sensors, and thus is a promising scheme to solve the energy-limited problem for the UWASNs. In this paper, we propose the integration of WIPT into the UWASNs and provide an overview on various enabling techniques for the WIPT based UWASNs(WIPT-UWASNs) as well as pointing out future research challenges and opportunities for WIPT-UWASNs.
基金the collaborative research program from the Microwave Energy Transmission Laboratory(METLAB)Research Insti⁃tute for Sustainable Humanosphere(RISH)Kyoto University and National Institute of Information and Communications Technology(NICT),JAPAN under Grant No.02401.
文摘Applications using simultaneous wireless information and power transfer(SWIPT)have increased significantly.Wireless communication technologies can be combined with the Internet of Things to develop many innovative applications using SWIPT,which is mainly based on wireless energy harvesting from electromagnetic waves used in communications.Wireless power transfer that uses magnetrons has been developed for communication technologies.Injection-locked magnetrons that can be used to facilitate high-power SWIPT for several devices are reviewed in this paper.This new technology is expected to pave the way for promoting the application of SWIPT in a wide range of fields.
基金the financial support of National Natural Science Foundation of China(NSFC),Grant No.61971102,61871076the Key Research and Development Program of Zhejiang Province under Grant No.2022C01093.
文摘Activating Wireless Power Transfer (WPT) in Radio-Frequency (RF) to provide on-demand energy supply to widely deployed Internet of Everything devices is a key to the next-generation energy self-sustainable 6G network. However, Simultaneous Wireless Information and Power Transfer (SWIPT) in the same RF bands is challenging. The majority of previous studies compared SWIPT performance to Gaussian signaling with an infinite alphabet, which is impossible to implement in any realistic communication system. In contrast, we study the SWIPT system in a well-known Nakagami-m wireless fading channel using practical modulation techniques with finite alphabet. The attainable rate-energy-reliability tradeoff and the corresponding rationale are revealed for fixed modulation schemes. Furthermore, an adaptive modulation-based transceiver is provided for further expanding the attainable rate-energy-reliability region based on various SWIPT performances of different modulation schemes. The modulation switching thresholds and transmit power allocation at the SWIPT transmitter and the power splitting ratios at the SWIPT receiver are jointly optimized to maximize the attainable spectrum efficiency of wireless information transfer while satisfying the WPT requirement and the instantaneous and average BER constraints. Numerical results demonstrate the SWIPT performance of various fixed modulation schemes in different fading conditions. The advantage of the adaptive modulation-based SWIPT transceiver is validated.
基金the National Key Research and Development Program of China under Grant Nos.2017YFA0700201,2017YFA0700202,2017YFA0700203,and 2021YFA1401001the 111 Project under Grant No.111⁃2⁃05,National Natural Science Foundation of China under Grant No.62001342+1 种基金Key Research and Development Program of Shaanxi under Grant No.2021TD⁃07Outstanding Youth Science Foundation of Shaanxi Province under Grant No.2019JC⁃15.
文摘Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous wireless information and power transfers(SWIPT),offering an optimized wireless energy management network.Both transmitting and receiving sides of the proposed solution are presented in detail.On the transmitting side,employing the wireless power transfer(WPT)technique,we present versatile power conveying strategies for near-field or far-field targets,single or multiple targets,and equal or unequal power targets.On the receiving side,utilizing the wireless energy harvesting(WEH)technique,we report our work on multi-functional rectifying metasurfaces that collect the wirelessly transmitted energy and the ambient energy.More importantly,a numerical model based on the plane-wave angular spectrum method is investigated to accurately calculate the radiation fields of PMS in the Fresnel and Fraunhofer regions.With this model,the efficiencies of WPT between the transmitter and the receiver are analyzed.Finally,future research directions are discussed,and integrated PMS for wireless information and wireless power is outlined.
基金partially supported by the National Natural Science Foundation of China(61571225,61271255,61232016,U1405254)the Open Foundation of Jiangsu Engineering Center of Network Monitoring(Nanjing University of Information Science and Technology)(Grant No.KJR1509)+2 种基金the PAPD fundthe CICAEET fundShenzhen Strategic Emerging Industry Development Funds(JSGG20150331160845693)
文摘Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Rayleigh fading channel.A novel EE that is defined as the average transmission rate divided by the total consumed power is introduced.In accordance with this definition,an adaptive power allocation(PA) scheme for DAS is proposed to maximize the EE under the maximum transmit power constraint.The solution of PA in the constrained EE optimization does exist and is unique.A practical iterative algorithm with Newton method is presented to obtain the solution of PA.The proposed scheme includes the one under perfect CSI as a special case,and it only needs large scale and statistical information.As a result,the scheme has low overhead and good robustness.The theoretical EE is also derived for performance evaluation,and simulation result shows the validity of the theoretical analysis.Moreover,EE can be enhanced by decreasing the estimation error and/or path loss exponents.
基金supported by STI2030-Major Projects(2021ZD0204300 and 2022ZD0205000)the National Natural Science Foundation of China(32020103009)+2 种基金a Ministry Key Project(GW089000)the Scientific Foundation of the Institute of Psychology,Chinese Academy of Sciences(E2CX4215CX)the CAAE Epilepsy Research Fund-UCB Fund(CU-2023-052).
文摘Direct electrical stimulation of the human cortex can produce subjective visual sensations,yet these sensations are unstable.The underlying mechanisms may stem from differences in electrophysiological activity within the distributed network outside the stimulated site.To address this problem,we recruited 69 patients who experienced visual sensations during invasive electrical stimulation while intracranial electroencephalography(iEEG)data were recorded.We found significantly flattened power spectral slopes in distributed regions involving different brain networks and decreased integrated information during elicited visual sensations compared with the non-sensation condition.Further analysis based on minimum information partitions revealed that the reconfigured network interactions primarily involved the inferior frontal cortex,posterior superior temporal sulcus,and temporoparietal junction.The flattened power spectral slope in the inferior frontal gyrus was also correlated with integrated information.Taken together,this study indicates that the altered electrophysiological signatures provide insights into the neural mechanisms underlying subjective visual sensations.
基金supported in part by the Shenzhen Basic Research Program under Grant JCYJ20220531103008018,and Grants 20231120142345001 and 20231127144045001the Natural Science Foundation of China under Grant U20A20156.
文摘The performance of traditional regular Intelligent Reflecting Surface(IRS)improves as the number of IRS elements increases,but more reflecting elements lead to higher IRS power consumption and greater overhead of channel estimation.The Irregular Intelligent Reflecting Surface(IIRS)can enhance the performance of the IRS as well as boost the system performance when the number of reflecting elements is limited.However,due to the lack of radio frequency chain in IRS,it is challenging for the Base Station(BS)to gather perfect Channel State Information(CSI),especially in the presence of Eavesdroppers(Eves).Therefore,in this paper we investigate the minimum transmit power problem of IIRS-aided Simultaneous Wireless Information and Power Transfer(SWIPT)secure communication system with imperfect CSI of BS-IIRS-Eves links,which is subject to the rate outage probability constraints of the Eves,the minimum rate constraints of the Information Receivers(IRs),the energy harvesting constraints of the Energy Receivers(ERs),and the topology matrix constraints.Afterward,the formulated nonconvex problem can be efficiently tackled by employing joint optimization algorithm combined with successive refinement method and adaptive topology design method.Simulation results demonstrate the effectiveness of the proposed scheme and the superiority of IIRS.
文摘In the Internet of Things(IoT)based scenarios,the network may encounter significant issues related to energy and communication as a result of a progressively growing number of terminals.We introduce simultaneous wireless power transfer(SWIPT)technology assisted by a reconfigurable intelligent surface(RIS)to counteract this challenge.Thus,the network’s flexibility and reliability will be further enhanced.According to this system architecture,the scattering-parameter-based communication model is introduced to disclose hardware features for an energy efficiency(EE)maximization problem.Specifically,the potential unauthorized demodulation is also considered in the problem formulation.To resolve the issue,an alternative strategy is utilized to optimize iteratively the coupled variables.In particular,the block coordinate descent(BCD)approach based on the Sherman-Morrison formula is proposed to solve the RIS subproblem.The numerical results prove the hardware effects cannot be dismissed lightly.Besides,the configuration of the RIS may impact the network performance directly.
