针对6G时代将会是移动通信与人工智能紧密结合的时代,产生数量庞大的边缘智能信号处理节点的趋势,提出了一种可部署于资源受限的边缘设备上的高效智能电磁信号识别模型。首先,通过绘制电磁信号的星座图将电磁信号具象为二维图像,并根据...针对6G时代将会是移动通信与人工智能紧密结合的时代,产生数量庞大的边缘智能信号处理节点的趋势,提出了一种可部署于资源受限的边缘设备上的高效智能电磁信号识别模型。首先,通过绘制电磁信号的星座图将电磁信号具象为二维图像,并根据归一化点密度对星座图上色以实现特征增强;然后,使用二值化深度神经网络对其进行识别,在保证识别准确率的同时明显降低了模型存储开销以及计算开销。采用电磁信号调制识别问题进行验证,实验选取常用的8种数字调制信号,选择加性高斯白噪声为信道环境。实验结果表明,所提方案可以在信噪比为-6~6 d B的噪声条件下获得96.1%的综合识别率,网络模型大小仅为166 KB,部署于树莓派4B的执行时间为290 ms,相比于同规模的全精度网络,准确率提升了0.6%,模型缩减到1/26.16,运行时间缩减到1/2.37。展开更多
CoFe2O4-BaTiO3 particulate composites were prepared by wet ball milling method,their magnetoelectric（ME） effect was studied as a function of their constituents and modulation frequency.The results show that the ME c...CoFe2O4-BaTiO3 particulate composites were prepared by wet ball milling method,their magnetoelectric（ME） effect was studied as a function of their constituents and modulation frequency.The results show that the ME coefficient increases as a function of modulation frequency from 400 to 1000 Hz and the ME characteristics of ME curves are also modified because the electrical conductivity of the CoFe2O4 phase is sensitive to the increase in frequency between 400 and 1 000 Hz.The third phase Ba2Fe2O5 formed during the sintering tends to reduce the ME effect.展开更多
Instead of avoiding occurrence of chaos in motor drives, chaos is positively utilized in this paper. A new chaotic pulse width modulation （PWM） scheme is proposed and implemented for AC motors, which functions to si...Instead of avoiding occurrence of chaos in motor drives, chaos is positively utilized in this paper. A new chaotic pulse width modulation （PWM） scheme is proposed and implemented for AC motors, which functions to significantly suppress harmonic peaks and hence acoustic noise. The key is to employ the Chua＇s circuit for generating a desired chaotic sequence. By using a practical induction motor, computer simulation and experimental results verify that the chaotic PWM has advantages of harmonic peak suppression and simple hardware implementation over the conventional PWM and random PWM.展开更多
Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance （ CMR ） , charge-orbital order and phas...Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance （ CMR ） , charge-orbital order and phase separation. Recently, an extraordinary anisotropic magnetoresistance （ AMR ） has been observed in perovskite manganite single crystals. The AMR value is about 2 orders larger than that of the conventional 3E transition metals and alloys, which is attributed to tunable metal-insulator transition temperature modulated by the magnetic field. This result provides a new route for exploring novel AMR materials and their applications.展开更多
Vehicle height and leveling control of electronically controlled air suspension(ECAS) still poses theoretical challenges for researchers that have not been adequately addressed in prior research. This paper investigat...Vehicle height and leveling control of electronically controlled air suspension(ECAS) still poses theoretical challenges for researchers that have not been adequately addressed in prior research. This paper investigates the design and verification of a new controller to adjust the vehicle height and to regulate the roll and pitch angles of the vehicle body(leveling control) during the height adjustment procedures. A nonlinear mechanism model of the vehicle height adjustment system is formulated to describe the dynamic behaviors of the system. By using mixed logical dynamical(MLD) approach, a novel control strategy is proposed to adjust the vehicle height by controlling the on-off statuses of the solenoid valves directly. On this basis, a correction algorithm is also designed to regulate the durations of the on-off statuses of the solenoid valves based on pulse width modulated(PWM) technology, thus the effective leveling control of the vehicle body can be guaranteed. Finally, simulations and vehicle tests results are presented to demonstrate the effectiveness and applicability of the proposed control methodology.展开更多
Electron spin-polarization modulation with a ferromagnetic strip of in-plane magnetization is analyzed in a hybrid ferromagnet/semiconductor filter device.The dependencies of electron spin-polarization on the strip’s...Electron spin-polarization modulation with a ferromagnetic strip of in-plane magnetization is analyzed in a hybrid ferromagnet/semiconductor filter device.The dependencies of electron spin-polarization on the strip’s magnetization strength,width and position have been systematically investigated.A novel magnetic control spin-polarization switch is proposed by inserting a ferromagnetic metal(FM)strip eccentric in relation to off the center of the spin filter,which produces the first energy level spin-polarization reversal.It is believed to be of significant importance for the realization of semiconductor spintronics multiple-value logic devices.展开更多
文摘针对6G时代将会是移动通信与人工智能紧密结合的时代,产生数量庞大的边缘智能信号处理节点的趋势,提出了一种可部署于资源受限的边缘设备上的高效智能电磁信号识别模型。首先,通过绘制电磁信号的星座图将电磁信号具象为二维图像,并根据归一化点密度对星座图上色以实现特征增强;然后,使用二值化深度神经网络对其进行识别,在保证识别准确率的同时明显降低了模型存储开销以及计算开销。采用电磁信号调制识别问题进行验证,实验选取常用的8种数字调制信号,选择加性高斯白噪声为信道环境。实验结果表明,所提方案可以在信噪比为-6~6 d B的噪声条件下获得96.1%的综合识别率,网络模型大小仅为166 KB,部署于树莓派4B的执行时间为290 ms,相比于同规模的全精度网络,准确率提升了0.6%,模型缩减到1/26.16,运行时间缩减到1/2.37。
基金The TGIST scholarship (TG-33-12-51-048D) is granted to the first author by the National Metal and Materials Technology Center (MTEC) of NSTDA
文摘CoFe2O4-BaTiO3 particulate composites were prepared by wet ball milling method,their magnetoelectric（ME） effect was studied as a function of their constituents and modulation frequency.The results show that the ME coefficient increases as a function of modulation frequency from 400 to 1000 Hz and the ME characteristics of ME curves are also modified because the electrical conductivity of the CoFe2O4 phase is sensitive to the increase in frequency between 400 and 1 000 Hz.The third phase Ba2Fe2O5 formed during the sintering tends to reduce the ME effect.
基金Project supported by the Shanghai Leading Academic Discipline Project (Grant No.T0103)
文摘Instead of avoiding occurrence of chaos in motor drives, chaos is positively utilized in this paper. A new chaotic pulse width modulation （PWM） scheme is proposed and implemented for AC motors, which functions to significantly suppress harmonic peaks and hence acoustic noise. The key is to employ the Chua＇s circuit for generating a desired chaotic sequence. By using a practical induction motor, computer simulation and experimental results verify that the chaotic PWM has advantages of harmonic peak suppression and simple hardware implementation over the conventional PWM and random PWM.
基金supported by National Natural Science Foundation of China(10874192)
文摘Perovskite manganites show exotic functionalities due to the coupling between spin, charge, orbital and lattice, such as metal-insulator transition, colossal magnetoresistance （ CMR ） , charge-orbital order and phase separation. Recently, an extraordinary anisotropic magnetoresistance （ AMR ） has been observed in perovskite manganite single crystals. The AMR value is about 2 orders larger than that of the conventional 3E transition metals and alloys, which is attributed to tunable metal-insulator transition temperature modulated by the magnetic field. This result provides a new route for exploring novel AMR materials and their applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.51375212,61403172&51305167)Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Key Research and Development Program of Jiangsu Province(Grant No.BE2016149)
文摘Vehicle height and leveling control of electronically controlled air suspension(ECAS) still poses theoretical challenges for researchers that have not been adequately addressed in prior research. This paper investigates the design and verification of a new controller to adjust the vehicle height and to regulate the roll and pitch angles of the vehicle body(leveling control) during the height adjustment procedures. A nonlinear mechanism model of the vehicle height adjustment system is formulated to describe the dynamic behaviors of the system. By using mixed logical dynamical(MLD) approach, a novel control strategy is proposed to adjust the vehicle height by controlling the on-off statuses of the solenoid valves directly. On this basis, a correction algorithm is also designed to regulate the durations of the on-off statuses of the solenoid valves based on pulse width modulated(PWM) technology, thus the effective leveling control of the vehicle body can be guaranteed. Finally, simulations and vehicle tests results are presented to demonstrate the effectiveness and applicability of the proposed control methodology.
基金supported by the National Basic Research Program of China(Grant No.2013CB934003)the State Key Laboratory of Software Development Environment(Grant No.SKLSDE-2013ZX-28)
文摘Electron spin-polarization modulation with a ferromagnetic strip of in-plane magnetization is analyzed in a hybrid ferromagnet/semiconductor filter device.The dependencies of electron spin-polarization on the strip’s magnetization strength,width and position have been systematically investigated.A novel magnetic control spin-polarization switch is proposed by inserting a ferromagnetic metal(FM)strip eccentric in relation to off the center of the spin filter,which produces the first energy level spin-polarization reversal.It is believed to be of significant importance for the realization of semiconductor spintronics multiple-value logic devices.
