By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of t...By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of the generalized multimode squeezed states are discussed.展开更多
In order to resolve the problean of the unbalanced threephase and unstable voltage, intellectual economized technique on elec- tricity based on electromagnetic regulation and control is proposed in this paper. We choo...In order to resolve the problean of the unbalanced threephase and unstable voltage, intellectual economized technique on elec- tricity based on electromagnetic regulation and control is proposed in this paper. We choose the TMS320LF2407A as the control chip and stepper motor as the executing agency. The equipment controls the movable contact reaching to the assigned position on the magnetic coil quickly and accurately, and outputs the sine-wave voltage steadily along with the network voltage variation though the fuzzy Porportional Integral Derivative（PID） control algorithm of integral separation and incremental mode with setting dead area. The principle of work and the key technique on the electromagnetic regulation and control are introduced in detail in this paper. The experiment result gives a proof for all the algorithm mentioned in this paper.展开更多
A method of feedforward compensation for electromotive force(EMF) in the single-phase permanent magnet linear generation system and a research in the performance of the single-phase PMLG system are presented.A general...A method of feedforward compensation for electromotive force(EMF) in the single-phase permanent magnet linear generation system and a research in the performance of the single-phase PMLG system are presented.A general mathematical model for the single-phase permanet magnet linear generator(PMLG) system is established and the current loop,voltage loop and the feedforward control are studied based on it for the control system.Then this paper analyses the transfer function of the power system,optimizes current loop and voltage loop parameters by engineering algorithm,and calculates the optimal control parameters.An EMF feedforward compensation method is developed to optimize the control system which improves dynamic performance of the power system but does not affect the steady-state performance.The result of this research verifies the correctness and rationality of the design for the control system.展开更多
The electric control of magnetic properties based on magnetoelectric effect is crucial for the development of future data storage devices.Here,based on first-principles calculations,a strong magnetoelectric effect is ...The electric control of magnetic properties based on magnetoelectric effect is crucial for the development of future data storage devices.Here,based on first-principles calculations,a strong magnetoelectric effect is proposed to effectively switch on/off the magnetic states as well as alter the in-plane/perpendicular easy axes of metal-phthalocyanine molecules(MPc)by reversing the electric polarization of the underlying two-dimensional(2D)ferroelectric a-In2Se3 substrate with the application of an external electric field.The mechanism originates from the different hybridization between the molecule and the ferroelectric substrate in which the different electronic states of surface Se layer play a dominant role.Moreover,the magnetic moments and magnetic anisotropy energies(MAE)of OsPc/In2Se3 can be further largely enhanced by a functionalized atom atop the OsPc molecule.The I-OsPc/In2Se3 system possesses large MAE up to 30 meV at both polarization directions,which is sufficient for room-temperature applications.These findings provide a feasible scheme to realize ferroelectric control of magnetic states in 2D limit,which have great potential for applications in nanoscale electronics and spintronics.展开更多
The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/trib...The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/triboelectric hybrid generator, which does not use complex structure and has high steady output performance. It includes three parts: magnetically levitated generator(MLG), piezoelectric generator(PNG), triboelectric nanogenerator(TENG). The peak power of each is 135 μW, 22 mW and3.6 mW, which are obtained at 1 MΩ, 10 kΩ and 1 kΩ, respectively. The hybrid generator can completely light up light-emitting diodes(LEDs) under the vibration frequency of 20 Hz and the vibration amplitude of 10 mm. It also can charge a 470 μF capacitor.On this basis, we have integrated the hybrid generaor as a power supply into a self-powered tempreature sensing system. The combination of three generators can not only broaden the operating range, but also increase the operating length and sensitivity.This work will extend the application of self-powered sensor in automatic production line and promote the development of industrial control technology.展开更多
文摘By means of the invariance of Weyl ordering under similar transformations we derive the explicit form of the generalized multimode squeezed states. Moreover, the completeness relation and the squeezing properties of the generalized multimode squeezed states are discussed.
基金supported by Natural Science Foundation of Shandong Province(No.Z2007F08)
文摘In order to resolve the problean of the unbalanced threephase and unstable voltage, intellectual economized technique on elec- tricity based on electromagnetic regulation and control is proposed in this paper. We choose the TMS320LF2407A as the control chip and stepper motor as the executing agency. The equipment controls the movable contact reaching to the assigned position on the magnetic coil quickly and accurately, and outputs the sine-wave voltage steadily along with the network voltage variation though the fuzzy Porportional Integral Derivative（PID） control algorithm of integral separation and incremental mode with setting dead area. The principle of work and the key technique on the electromagnetic regulation and control are introduced in detail in this paper. The experiment result gives a proof for all the algorithm mentioned in this paper.
基金Supported by the National High Technology Research and Development Program of China(No.2006AA05Z231)the National Natural Science Foundation of China(No.51177025)
文摘A method of feedforward compensation for electromotive force(EMF) in the single-phase permanent magnet linear generation system and a research in the performance of the single-phase PMLG system are presented.A general mathematical model for the single-phase permanet magnet linear generator(PMLG) system is established and the current loop,voltage loop and the feedforward control are studied based on it for the control system.Then this paper analyses the transfer function of the power system,optimizes current loop and voltage loop parameters by engineering algorithm,and calculates the optimal control parameters.An EMF feedforward compensation method is developed to optimize the control system which improves dynamic performance of the power system but does not affect the steady-state performance.The result of this research verifies the correctness and rationality of the design for the control system.
基金supported by the National Natural Science Foundation of China(11974307,61574123,11674299,and 11634011)National Key Research and Development Program of China(2017YFA0204904)+3 种基金Fundamental Research Funds for the Central Universities(2019FZA3004,WK2340000082,and WK2060190084)Zhejiang Provincial Natural Science Foundation(D19A040001)Anhui Initiative in Quantum Information Technologies(AHY170000)Strategic Priority Research Program of Chinese Academy of Sciences(XDB30000000)。
文摘The electric control of magnetic properties based on magnetoelectric effect is crucial for the development of future data storage devices.Here,based on first-principles calculations,a strong magnetoelectric effect is proposed to effectively switch on/off the magnetic states as well as alter the in-plane/perpendicular easy axes of metal-phthalocyanine molecules(MPc)by reversing the electric polarization of the underlying two-dimensional(2D)ferroelectric a-In2Se3 substrate with the application of an external electric field.The mechanism originates from the different hybridization between the molecule and the ferroelectric substrate in which the different electronic states of surface Se layer play a dominant role.Moreover,the magnetic moments and magnetic anisotropy energies(MAE)of OsPc/In2Se3 can be further largely enhanced by a functionalized atom atop the OsPc molecule.The I-OsPc/In2Se3 system possesses large MAE up to 30 meV at both polarization directions,which is sufficient for room-temperature applications.These findings provide a feasible scheme to realize ferroelectric control of magnetic states in 2D limit,which have great potential for applications in nanoscale electronics and spintronics.
基金supported by the National Natural Science Foundation of China(Grant Nos.61525107,51422510&51605449)the National High Technology Research and Development Program of China(Grant No.2015AA042601)
文摘The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/triboelectric hybrid generator, which does not use complex structure and has high steady output performance. It includes three parts: magnetically levitated generator(MLG), piezoelectric generator(PNG), triboelectric nanogenerator(TENG). The peak power of each is 135 μW, 22 mW and3.6 mW, which are obtained at 1 MΩ, 10 kΩ and 1 kΩ, respectively. The hybrid generator can completely light up light-emitting diodes(LEDs) under the vibration frequency of 20 Hz and the vibration amplitude of 10 mm. It also can charge a 470 μF capacitor.On this basis, we have integrated the hybrid generaor as a power supply into a self-powered tempreature sensing system. The combination of three generators can not only broaden the operating range, but also increase the operating length and sensitivity.This work will extend the application of self-powered sensor in automatic production line and promote the development of industrial control technology.
