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International Journal of Automation and computing 2014年第1期11卷 72-77页

作者： Jie-Sheng Wang Xiu-Dong Ren School of electronic and Information engineering University of Science and Technology Liaoning

According to the pulverized coal combustion flame image texture features of the rotary-kiln oxide pellets sintering process,a combustion working condition recognition method based on the generalized learning vector(GLVQ) neural network is ***,the numerical flame image is analyzed to extract texture features,such as energy,entropy and inertia,based on grey-level co-occurrence matrix(GLCM) to provide qualitative information on the changes in the visual appearance of the *** the kernel principal component analysis(KPCA) method is adopted to deduct the input vector with high dimensionality so as to reduce the GLVQ target dimension and network scale ***,the GLVQ neural network is trained by using the normalized texture feature *** test results show that the proposed KPCA-GLVQ classifer has an excellent performance on training speed and correct recognition rate,and it meets the requirement for real-time combustion working condition recognition for the rotary kiln process.

关键词： Rotary kiln pellets sintering texture features grey-level co-occurrence matrix kernel principal component analysis generalized learning vector quantization

Topological properties in ABA trilayer graphene under the irradiation of light

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Chinese Physics B 2019年第11期28卷 322-325页

作者： Liang Chen School of Physics and electronic engineering Taishan UniversityTaian 271000China

We study ABA trilayer graphene under irradiation of a circularly polarized light. In high-frequency regime, the effective low-energy Hamiltonian is obtained based on the Floquet theory. With increasing circularly polarized light intensity,the band structure shows a band gap closing and reopening, which happen twice. The process of the band gap closing and reopening is accompanied with a topological phase transition. We investigate the Chern numbers and the anomalous Hall conductivities to confirm the topological phase transition. The interplay between light-induced circularity-dependent effective potential and effective sublattice potential is discussed.

关键词： graphene light Flouqet theory Hall

Random-injection-based two-channel chaos with enhanced bandwidth and suppressed time-delay signature by mutually coupled lasers: Proposal and numerical analysis

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Chinese Physics B 2021年第1期30卷 239-247页

作者： Shi-Rong Xu Xin-Hong Jia Hui-Liang Ma Jia-Bing Lin Wen-Yan Liang Yu-Lian Yang College of Physics and electronic engineering Sichuan Normal UniversityChengdu 610101China

Simultaneous bandwidth(BW) enhancement and time-delay signature(TDS) suppression of chaotic lasing over a wide range of parameters by mutually coupled semiconductor lasers(MCSLs) with random optical injection are proposed and numerically investigated. The influences of system parameters on TDS suppression(characterized by autocorrelation function(ACF) and permutation entropy(PE) around characteristic time) and chaos BW are investigated. The results show that, with the increasing bias current, the ranges of parameters(detuning and injection strength) for the larger BW(> 20 GHz) are broadened considerably, while the parameter range for optimized TDS( 20 GHz)and perfect TDS suppression. In addition, the system can generate two-channel high-speed truly physical random number sequences at 200 Gbits/s for each channel.

关键词： random distributed feedback-based optical injection two-channel chaos lasing bandwidth enhancement and time-delay signature suppression physical random number generation

Design of nonuniform cosine-modulated filter-banks with the perfect-reconstruction property and arbitrary filter lengths

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Progress in Natural Science:Materials International 2007年第3期17卷 340-345页

作者： XIE Xuemei (School of electronic engineering, Xidian University, Xi’an 710071, China) School of electronic engineering Xidian University Xi''an 710071 China

In this paper, a method is proposed to construct recombination nonuniform cosine-modulated filter banks (CMFBs) with a perfect-reconstruction property and with arbitrary filter lengths. In this filter bank (FB) structure, certain channels of an original M-channel uniform FB are merged by a set of transmultiplexers (TMUXs), yielding nonuniform outputs, and the length restrictions on the original CMFB and the recombination TMUXs are avoided, allowing them to have arbitrary filter lengths. By imposing certain improved matching conditions on the prototype filters, nonuniform FBs with arbitrary filter lengths and with good properties can be obtained. As a result, the flexibility of selecting modulation types and filter lengths is greatly increased in the design of recombination nonuniform CMFBs. Another benefit due to the flexibility is that the system delay can be reduced.

关键词： recombination nonunlform cosine-modulated filter bank transmultiplexer perfect-reconstruction arbitrary-length.

Effects of the Antiferromagnetic Spin Coupling and Interdot Coulomb Repulsion on Kondo Effects in Serial Double Quantum Dots

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Chinese Physics Letters 2014年第4期31卷 139-142页

作者： LI Zeng-Peng WU Shao-Quan ZHAO Guo-Ping College of Physics and electronic engineering Siehuan Normal University Chengdu 610086

We theoretically study the effects of the antiferromagnetic （AF） spin coupling and the interdot Coulomb repulsion on the Kondo effects in serial double quantum dots by means of the slave-boson mean-field approximation. Our results indicate that in the weak coupling regime, the AF spin coupling strengthens the Kondo resonance, while the interdot Coulomb repulsion suppresses them for the equilibrium case. In the non-equilibrium case, the AF spin coupling strengthens the Kondo resonance only when J 〉 2.5TK0, while the interdot Coulomb repulsion does not suppress Kondo peaks. In the strong coupling regime, the bias voltage has no effects on the Kondo resonance in this system, and the AF spin coupling increases the height of Kondo peaks only when J 〈 2.5TK0. However, the inter-dot Coulomb repulsion suppresses the spin Kondo effect, which induces the orbit Kondo effect. Moreover, the relevant underlying physics of these problems are discussed.

关键词： ANTIFERROMAGNETIC resonance SPIN-spin interactions COULOMB potential KONDO effect QUANTUM dots

Multiple model efficient particle filter based track-before-detect for maneuvering weak targets

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Journal of Systems engineering and electronics 2020年第4期31卷 647-656页

作者： BAO Zhichao JIANG Qiuxi LIU Fangzheng College of electronic and engineering National University of Defense and TechnologyHefei 230037China

It is a tough problem to jointly detect and track a weak target, and it becomes even more challenging when the target is maneuvering. The above problem is formulated by using the Bayesian theory and a multiple model(MM) based filter is proposed. The filter presented uses the MM method to accommodate the multiple motions that a maneuvering target may travel under by adding a random variable representing the motion model to the target state. To strengthen the efficiency performance of the filter,the target existence variable is separated from the target state and the existence probability is calculated in a more efficient way. To examine the performance of the MM based approach, a typical track-before-detect(TBD) scenario with a maneuvering target is used for simulations. The simulation results indicate that the MM based filter proposed has a good performance in joint detecting and tracking of a weak and maneuvering target, and it is more efficient than the general MM method.

关键词： particle filter track-before-detect(TBD) maneuvering target tracking multiple model(MM)

The dynamics of a memristor-based Rulkov neuron with fractional-order difference

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Chinese Physics B 2022年第6期31卷 30-38页

作者： Yan-Mei Lu Chun-Hua Wang Quan-Li Deng Cong Xu College of Computer Science and electronic engineering Hunan UniversityChangsha 410082China

The exploration of the memristor model in the discrete domain is a fascinating *** electromagnetic induction on neurons has also begun to be simulated by some discrete ***,most of the current investigations are based on the integer-order discrete memristor,and there are relatively few studies on the form of fractional *** this paper,a new fractional-order discrete memristor model with prominent nonlinearity is constructed based on the Caputo fractional-order difference ***,the dynamical behaviors of the Rulkov neuron under electromagnetic radiation are simulated by introducing the proposed discrete *** integer-order and fractional-order peculiarities of the system are analyzed through the bifurcation graph,the Lyapunov exponential spectrum,and the iterative *** results demonstrate that the fractional-order system has more abundant dynamics than the integer one,such as hyper-chaos,multi-stable and transient *** addition,the complexity of the system in the fractional form is evaluated by the means of the spectral entropy complexity algorithm and consequences show that it is affected by the order of the fractional *** feature of fractional difference lays the foundation for further research and application of the discrete memristor and the neuron map in the future.

关键词： discrete memristor Rulkov neuron fractional-order difference dynamics

Spin-Polarization in Quasi-Magnetic Tunnel Junctions

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Chinese Physics Letters 2017年第5期34卷 115-118页

作者：谢征微李玲 College of Physics and electronic engineering Sichuan Normal University Chengdu 610066

Spin polarization in ferromagnetic metal/insulator/spin-filter barrier/nonmagnetic metal, referred to as quasimagnetic tunnel junctions, is studied within the free-electron model. Our results show that large positive or negative spin-polarization can be obtained at high bias in quasi-magnetic tunnel junctions, and within large bias variation regions, the degree of spin-polarization can be linearly tuned by bias. These linear variation regions of spin-polarization with bias are influenced by the barrier thicknesses, barrier heights and molecular fields in the spin-filter （SF） layer. Among them, the variations of thickness and heights of the insulating and SF barrier layers have influence on the value of spin-polarization and the linear variation regions of spin-polarization with bias. However, the variations of molecular field in the SF layer only have influence on the values of the spin-polarization and the influences on the linear variation regions of spin-polarization with bias are slight.

关键词： Spin-Polarization in Quasi-Magnetic Tunnel Junctions TMR

Multi-objective optimization of gradient coil for benchtop magnetic resonance imaging system with high-resolution

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Chinese Physics B 2014年第2期23卷 589-596页

作者：王龙庆王为民 Institute of Quantum electronics School of Electronic Engineering and Computer SciencePeking University

Significant high magnetic gradient field strength is essential to obtaining high-resolution images in a benchtop mag- netic resonance imaging （BT-MRI） system with permanent magnet. Extending minimum wire spacing and maximum wire width of gradient coils is one of the key solutions to minimize the maximum current density so as to reduce the local heating and generate higher magnetic field gradient strength. However, maximum current density is hard to optimize together with field linearity, stored magnetic energy, and power dissipation by the traditional target field method. In this paper, a new multi-objective method is proposed to optimize the maximum current density, field linearity, stored magnetic energy, and power dissipation in MRI gradient coils. The simulation and experimental results show that the minimum wire spacings are improved by 159% and 62% for the transverse and longitudinal gradient coil respectively. The maximum wire width increases from 0.5 mm to 1.5 mm. Maximum gradient field strengths of 157 mT/m and 405 mT/m for transverse and lon- gitudinal coil are achieved, respectively. The experimental results in BT-MRI instrument demonstrate that the MRI images with in-plane resolution of 50 ~tm can be obtained by using the designed coils.

关键词： magnetic resonance imaging gradient coil target field method wire spacing

Reliability Based Design Optimization of Aero-Engine Spindle Ball Bearings

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Journal of Donghua University(English Edition) 2014年第6期31卷 853-855页

作者：杨静孟德彪张小玲汪忠来许焕卫 School of Mechanical Electronicand Industrial EngineeringUniversity of Electronic Science and Technology of China

Aero-engine spindle ball bearings work in harsh conditions which are affected by relatively complex stresses. One of the key factors which affects bearing performance is its structure. In this paper,we used reliability based design optimization method to solve the structure design problem of aero-engine spindle ball *** with the optimization design method, the value of equivalent dynamic load using reliability optimization design method was the least by MATLAB simulation. Also the design solutions show that the optimized structure possesses higher reliability than the original solution.

关键词： aero-engine spindle ball bearing complex stresses reliability based design optimization structure design