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Immune particle swarm optimization of linear frequency modulation in acoustic communication

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Journal of Systems Engineering and Electronics 2015年第3期26卷 450-456页

作者： Haipeng Ren Yang zhao Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology

With the exploration of the ocean, underwater acoustic communication has attracted more and more attention in recent years. The underwater acoustic channel is considered to be one of the most complicated channels because it suffers from more serious multipath effect, fewer available bandwidths and quite complex noise. Since the signals experience a serious distortion after being transmitted through the underwater acoustic channel, the underwater acoustic communication experiences a high bit error rate （BER）. To solve this problem, carrier waveform inter- displacement （CWlD） modulation is proposed. It has been proved that CWlD modulation is an effective method to decrease BER. The linear frequency modulation （LFM） carrier-waves are used in CWlD modulation. The performance of the communication using CWID modulation is sensitive to the change of the frequency band of LFM carrier-waves. The immune particle swarm optimization （IPSO） is introduced to search for the optimal frequency band of the LFM carrier-waves, due to its excellent performance in solving complicated optimization problems. The multi-objective and multi- peak optimization nature of the IPSO gives a suitable description of the relationship between the upper band and the lower band of the LFM carrier-waves. Simulations verify the improved perfor- mance and effectiveness of the optimization method.

关键词： underwater acoustic communication carrier waveform inter-displacement (CWlD) multi-objective optimization immune particle swarm optimization (IPSO).

In-plane forced vibration of curved pipe conveying fluid by Green function method

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Applied Mathematics and Mechanics(English Edition) 2017年第10期38卷 1397-1414页

作者： Qianli zhao Zhili SUN School of Mechanical Engineering and Automation Northeastern University

The Green function method （GFM） is utilized to analyze the in-plane forced vibration of curved pipe conveying fluid, where the randomicity and distribution of the external excitation and the added mass and damping ratio are considered. The Laplace transform is used, and the Green functions with various boundary conditions are obtained subsequently. Numerical calculations are performed to validate the present solutions, and the effects of some key parameters on both tangential and radial displacements are further investigated. The forced vibration problems with linear and nonlinear motion constraints are also discussed briefly. The method can be radiated to study other forms of forced vibration problems related with pipes or more extensive issues.

关键词： in-plane forced vibration curved pipe conveying fluid Green functionmethod (GFM) motion constraint

Model and Algorithm of Sequence-Based Quantum-Inspired Neural Networks

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Chinese Journal of Electronics 2018年第1期27卷 9-18页

作者： LI Panchi zhao Ya School of Computer and Information Technology Northeast Petroleum University

To enhance the approximation ability of traditional Artificial neural network(ANN), by introducing the quantum rotation gates and the multi-qubits controlled-NOT gates to ANN, we proposed a Sequence input-based quantum-inspired neural network(SIQNN).In our model, the hidden nodes are composed of some multi-qubits controlled-NOT gates, the inputs are described by the multi-dimensional discrete qubits sequences,the output nodes are the traditional neurons. The model parameters include the rotation angles of quantum rotation gates in hide layer and the weights in output *** learning algorithms were derived by employing the Levenberg-Marquardt algorithm. Simulation results of predicting the runoff of the Hongjiadu Reservoir show that,the SIQNN is obviously superior to the ANN.

关键词： Quantum computation Quantum rotation gate Multi-qubits controlled-NOT gate Quantum inspired neuron Quantum-inspired neural network

Plasmon-exciton interaction in colloidally fabricated metal nanoparticlequantum emitter nanostructures

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Nano Research 2019年第9期12卷 2164-2171页

作者： Yi Luo Jing zhao department of Chemistry University of Connecticut55 North Eagleville RoadStorrs06269USA Institute of Materials Science University of Connecticut97 North Eagleville RoadStorrs06269USA

When quantum emitters and plasmonic nanoparticles are in close vicinity,the energy exchange,termed as plasmon-exciton coupling,can make the absorption and emission behavior of the hybrid structure very different from those of the two constituents *** coupling strength between the two constituents highly depends on how the hybrid structure is *** a result,a diverse range of coupling effect arise including plasmon induced fluorescence quenching/enhancing (weak coupling),Fano interference (intermediate coupling),Rabi-splitting and lasing (strong coupling).The emergence of different coupling behavior can be controlled by the different combinations of quantum emitters and plasmonic nanoparticles as well as the spatial arrangement of the individual *** assembly/synthesis methods are essentially delicate strategies that can build the hybrid nanostructures with nanometer precision and allow for large-scale *** this review,we discuss the theoretical models that apply to different coupling behaviors,the optical properties of the hybrid systems,and the advancement of colloidal methods to manipulate the plasmon-exciton in the hybrid *** also provide perspectives on the challenges and future directions of the research in coupled plasmon-exciton nanosystems.

关键词： quantum emitter metal nanoparticles plasm on-exciton coupling colloidal assembly Purcell effect Rabi-splitting

Comparisons of urban-related warming in Beijing using different methods to calculate the daily mean temperature

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Science China Earth Sciences 2019年第4期62卷 693-702页

作者： deming zhao Jian WU CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences department of Atmospheric Science Yunnan University

To evaluate the contribution of urban surface expansion to regional warming using different methods to calculate the daily mean surface air temperature(SAT), satellite-based images displaying urban surface expansion over the past 37 years(1980–2016) across China were collected for use in nested numerical experiments using the weather research and forecasting(WRF) regional climate model. The contribution of urban surface expansion to urban-related warming was determined using the daily mean SAT averages based on four time records each day(00, 06, 12, and 18 h UTC, T_4) and averages of the SAT maximum(Tmax) and minimum(Tmin)(Txn). The contribution of urban surface expansion to urban-related warming(relative value) in Beijing was 0.110°C per decade(22.8% of total warming) for T_4 and 0.094°C per decade(20.2%) for Txn. The values obtained when using T_4 were larger than those obtained when using Txn. Differences in the urban-related warming calculated using T_4 and Txncould be attributed to the smaller changing trends in Txnin the urban-surface expansion experiment, which resulted from a large changing trend in Tminand a much smaller changing trend in Tmax. The changes in the diurnal cycle of the energy budget due to urban surface expansion induced changes in the diurnal cycle of SAT, as evidenced by the four time records each day, as well as Tmaxand Tmin. This was especially true for periods of intense urban surface expansion, although the annual mean SAT calculated using Txnwas larger than that calculated using T_4. The increase in impervious area(walls, streets, etc.) due to urban surface expansion, as well as the widespread use of building materials with a large heat capacity resulted in a marked increase in ground heat flux in the daytime. This restricted the increase in SAT in the daytime, but promoted it at night. The increases in SAT due to urban surface expansion were not symmetrical, being smaller in the daytime and larger at night.

关键词： Urban surface expansion Surface air temperature Daily mean temperature Changing trend Urban-related warming

Pareto Efficiency of Finite Horizon Switched Linear Quadratic Differential Games

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Journal of Systems Science & Complexity 2018年第1期31卷 173-187页

作者： HUANG Yabing zhao Jun College of Information Science and Engineering Northeastern University Shenyang 110819 China State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang 110819 China

A switched linear quadratic（LQ） differential game over finite-horizon is investigated in this paper. The switching signal is regarded as a non-conventional player, afterwards the definition of Pareto efficiency is extended to dynamics switching situations to characterize the solutions of this multi-objective problem. Furthermore, the switched differential game is equivalently transformed into a family of parameterized single-objective optimal problems by introducing preference information and auxiliary variables. This transformation reduces the computing complexity such that the Pareto frontier of the switched LQ differential game can be constructed by dynamic programming. Finally, a numerical example is provided to illustrate the effectiveness.

关键词： Dynamic optimization linear quadratic problems Pareto efficiency switched differential game

Mg-intercalation engineering of MnO_(2)electrode for high-performance aqueous magnesium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 1954-1962页

作者： Yue zhao Bei Wang Minjie Shi Shibo An Liping zhao Chao Yan School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory for Metallic Matrix Composite Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Rechargeable aqueous magnesium-ion batteries(MIBs)show great promise for low-cost,high-safety,and high-performance energy storage *** manganese dioxide(MnO_(2))is considered as a potential electrode material for aqueous MIBs,the low electrical conductivity and unsatisfactory cycling performance greatly hinder the practical application of MnO_(2)*** overcome these problems,herein,a novel Mg-intercalation engineering approach for MnO_(2)electrode to be used in aqueous MIBs is presented,wherein the structural regulation and electrochemical performance of the Mg-intercalation MnO_(2)(denoted as MMO)electrode were thoroughly investigated by density functional theory(DFT)calculations and in-situ Raman *** results demonstrate that the Mg intercalation is essential to adjusting the charge/ion state and electronic band gap of MMO electrode,as well as the highly reversible phase transition of the MMO electrode during the charging-discharging *** of these remarkable characteristics,the MMO electrode can be capable of delivering a significant specific capacity of~419.8 mAh·g^(−1),while exhibiting a good cycling capability over 1000 cycles in 1 M aqueous MgCl_(2) *** the basis of such MMO electrode,we have successfully developed a soft-packaging aqueous MIB with excellent electrochemical properties,revealing its huge application potential as the efficient energy storage devices.

关键词： manganese oxide aqueous batteries intercalation engineering density functional theory calculations in-situ Raman

PID controller design for second order nonlinear uncertain systems

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Science China(Information Sciences) 2017年第2期60卷 5-17页

作者： Cheng zhao Lei GUO Institute of Systems Science Academy of Mathematics and Systems Science (AMSS)Chinese Academy of Sciences

Although the classical PID(proportional-integral-derivative) controller is most widely and successfully used in engineering systems which are typically nonlinear with various uncertainties, almost all the existing investigations on PID controller focus on linear systems. The aim of this paper is to present a theory on PID controller for nonlinear uncertain systems, by giving a simple and analytic design method for the PID parameters together with a mathematic proof for the global stability and asymptotic regulation of the closed-loop control systems. To be specific, we will construct a 3-dimensional manifold within which the three PID parameters can be chosen arbitrarily to globally stabilize a wide class of second order nonlinear uncertain dynamical systems, as long as some knowledge on the upper bound of the derivatives of the nonlinear uncertain function is *** will also try to make the feedback gains as small as possible by investigating the necessity of the manifold from which the PID parameters are chosen, and to establish some necessary and sufficient conditions for global stabilization of several special classes of nonlinear uncertain systems.

关键词： PID controller nonlinear uncertain systems global stability Lyapunov function asymptotic regulation

Monolithic integration of flexible lithium-ion battery on a plastic substrate by printing methods

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Nano Research 2019年第10期12卷 2477-2484页

作者： Zhenxuan zhao Huaqiang Wu Institute of Microelectronics Tsinghua UniversityBeijing 100084China

En ergy storage devices with flexible form factor have become critical components of wearable electr onic *** spired by methods of monolithic integration in the microelectronics fabrication process,we propose a planar flexible full-solid-state lithium-ion battery(FSLB)architecture and a layer-by-layer stencil printing assembly method for fabricating batteries on polyethylene terephthalate(PET)*** use quasi-solid electrolyte based on LiTFSI and ultraviolet(UV)-curable ethoxylated trimethylolpropane triacrylate(ETPTA)polymeric matrix in combination with Li4Ti50i2(LTO)/LiFePO4(LFP)-based *** mechanical flexibility(der assembly processes,are promising.A complete thin film-shape FSLB demonstrated working operation both under planar and bending *** unique architecture and assembly processes open new ways for planar flexible devices to be integrated with flexible energy devices.

关键词： flexible printable full-solid-state battery lithium-ion battery polymer electrolyte