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UAV swarm formation reconfiguration control based on variable-stepsize MPC-APCMPIO algorithm

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Science China(information Sciences) 2023年第11期66卷 222-243页

作者： Jian LIAO Jun CHENG Bin XIN Delin LUO Lihui ZHENG Yuhang KANG Shaolei ZHOU school of Physics and electronic information Gannan Normal University Shenzhen Institute of Advanced Technology Chinese Academy of Sciences school of Automation Beijing Institute of Technology school of Aerospace engineering Xiamen University school of electronic information Northwest University of Technology 6. School of Basic Science Naval Aviation University of PLA

For a complex operational environment, to actualize safe obstacle avoidance and collision avoidance, a swarm must be capable of autonomous formation reconfiguration. First, this paper introduces the basic pigeon-inspired optimization(PIO) algorithm, and establishes the unmanned aerial vehicle motion model and the virtual leader swarm formation control structure. Then, given the above knowledge, the basic error objective function of a UAV swarm, obstacle avoidance objective function, and collision avoidance objective function are devised based on the variable-stepsize model predictive control technique. Next,the adaptive perception Cauchy mutation PIO algorithm is proposed by introducing the Cauchy mutation operator, adaptive weight factor, and roulette wheel selection into the basic PIO. This algorithm is used to optimally solve the abovementioned swarm objective functions. Ultimately, a set of comparative simulations are performed to verify the effectiveness and reliability of the proposed algorithm.

关键词： unmanned aerial vehicle swarm formation reconfiguration variable-stepsize model predictive control (MPC) adaptive perception Cauchy mutation pigeon-inspired optimization (APCMPIO) obstacle avoidance

Learning Bayesian network parameters under new monotonic constraints

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Journal of Systems engineering and electronics 2017年第6期28卷 1248-1255页

作者： Ruohai Di Xiaoguang Gao Zhigao Guo school of electronic and information Northwestern Polytechnical University Xi’an 710129 China

When the training data are insufficient, especially when only a small sample size of data is available, domain knowledge will be taken into the process of learning parameters to improve the performance of the Bayesian networks. In this paper, a new monotonic constraint model is proposed to represent a type of common domain knowledge. And then, the monotonic constraint estimation algorithm is proposed to learn the parameters with the monotonic constraint model. In order to demonstrate the superiority of the proposed algorithm, series of experiments are carried out. The experiment results show that the proposed algorithm is able to obtain more accurate parameters compared to some existing algorithms while the complexity is not the highest.

关键词： Bayesian networks parameter learning new mono tonic constraint

Comparative Study of Monolayer and Bilayer Epitaxial Graphene Field-Effect Transistors on SiC Substrates

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Chinese Physics Letters 2016年第8期33卷 100-104页

作者：何泽召杨克武蔚翠刘庆彬王晶晶宋旭波韩婷婷冯志红蔡树军 school of electronic and information engineering Hebei University of Technology National Key Laboratory of ASIC Hebei Semiconductor Research Institute

Monolayer and bilayer graphenes have generated tremendous excitement as the potentially useful electronic materials due to their unique features. We report on monolayer and bilayer epitaxial graphene field-effect transistors （GFETs） fabricated on SiC substrates. Compared with monolayer GFETs, the bilayer GFETs exhibit a significant improvement in dc characteristics, including increasing current density I DS, improved transconductance g m, reduced sheet resistance lion, and current saturation. The improved electrical properties and tunable bandgap in the bilayer graphene lead to the excellent dc performance of the bilayer GFETs. Furthermore, the improved dc characteristics enhance a better rf performance for bilayer graphene devices, demonstrating that the quasifree-standing bilayer graphene on SiC substrates has a great application potential for the future graphene-based electronics.

关键词： of in is for SiC Comparative Study of Monolayer and Bilayer Epitaxial Graphene Field-Effect Transistors on SiC Substrates on

Enhancement of nonlinear optical phenomena from crown-like nanostructure zinc oxide based on whispering gallery mode

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Optoelectronics Letters 2014年第1期10卷 1-4页

作者：王马华朱光平朱汉清居勇峰季仁东付丽辉 Faculty of electronic and Electrical engineering Huaiyin Institute of Technology school of Physics and electronic information Huaibei Normal University

Whispering gallery mode(WGM)-enhanced nonlinear optical phenomena from crown-like nanostructure zinc oxide(ZnO)samples are *** samples are synthesized by vapor-phase transport *** morphology and crystal structure are examined and characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and high-resolution transmission electron microscopy(HRTEM),and they are excited by femtosecond laser pulses with central wavelengths of 355 nm,800 nm and 1150 nm,*** typical stimulated emission presents a red shift compared with spontaneous emission,which is observed under the excitation of 355 nm with a relatively low *** ultraviolet(UV)frequency up-conversion emission is obtained when the excitation pulse wavelengths are selected as 800nm and 1150 nm,*** peak position and the relationship between the emission intensity and excitation intensity demonstrate that the UV up-conversion photoluminescence(PL)is induced by two-and three-photon *** PL characteristics and their WGM-enhanced mechanism are investigated.

关键词：纳米结构回音壁模式光学现象非线性氧化锌高分辨透射电子显微镜扫描电子显微镜频率上转换

Multi-level Deep Correlative Networks for Multi-modal Sentiment Analysis

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Chinese Journal of electronics 2020年第6期29卷 1025-1038页

作者： CAI Guoyong LYU Guangrui LIN Yuming WEN Yimin school of Computer Science and information Security Guilin University of Electronic Technology school of information Science and Technology Dalian Maritime University

Multi-modal sentiment analysis(MSA)is increasingly becoming a hotspot because it extends the conventional Sentiment analysis(SA) based on texts to multi-modal content which can provide richer affective ***,compared with textbased sentiment analysis,multi-modal sentiment analysis has much more challenges,because the joint learning process on multi-modal data requires both fine-grained semantic matching and effective heterogeneous feature *** approaches generally infer sentiment type from splicing features extracted from different modalities but neglect the strong semantic correlation among cooccurrence data of different *** solve the challenges,a multi-level deep correlative network for multimodal sentiment analysis is proposed,which can reduce the semantic gap by analyzing simultaneously the middlelevel semantic features of images and the hierarchical deep ***,the most relevant cross-modal feature representation is generated with Multi-modal Deep and discriminative correlation analysis(Multi-DDCA) while keeping those respective modal feature representations to be ***,the high-level semantic outputs from multi-modal deep and discriminative correlation analysis are encoded into attention-correlation cross-modal feature representation through a co-attention-based multimodal correlation submodel,and then they are further merged by multi-layer neural network to train a sentiment classifier for predicting sentimental *** experimental results on five datasets demonstrate the effectiveness of the designed approach,which outperforms several state-of-the-art fusion strategies for sentiment analysis.

关键词： conventional Sentiment analysis discriminative correlation analysis Multimodal Deep Image recognition text-based sentiment analysis multilayer neural network Document processing techniques Multilevel Deep correlative networks text analysis Data handling techniques image fusion multimodal content Optical, image and video signal processing multilevel deep correlative network Computer vision and image processing techniques feature extraction respective modal feature representations relevant cross-modal feature representation attention-correlation cross-modal feature representation multimodal data image representation multimodal sentiment analysis learning (artificial intelligence) pattern classification Knowledge engineering techniques

Effect of Ba/Sr ratio on the nonlinear optical properties of Ba_(1-x)Sr_(x)TiO_(3)(x = 0.1–0.9) thin films

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Chinese Optics Letters 2023年第4期21卷 74-79页

作者：王得鹏牛瑞峰崔立棋王伟田 school of Physics and electronic information Yantai UniversityShandong 264005China

Perovskite-structured barium strontium titanate[Ba_(1-x)Sr_(x)Ti O_(3),x=0.1–0.9] films have been epitaxially fabricated by using a pulsed-laser deposition *** third-order nonlinear optical properties were studied through a z-scan method,allowing the resolution of the nonlinear refractive and absorptive contributions to the *** all the samples show almost the same value of nonlinear absorption coefficient,the extracted nonlinear refractive index of the sample of x=0.3 is apparently larger than that of other *** of the nonlinear optical properties on the Ba/Sr ratio is discussed in terms of the crystal phase transformation and metal-oxygen bond length of the selected materials.

关键词： nonlinear optical properties thin films phase transformation pulsed-laser deposition

Recent advances in two-step energy transfer light-harvesting systems driven by non-covalent self-assembly

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Chinese Chemical Letters 2024年第1期35卷 31-39页

作者： Zhiying Wu Hongwei Qian Xiuxiu Li Tangxin Xiao Leyong Wang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Sequential energy transfer is ubiquitous in natural light-harvesting systems(LHSs),which greatly promotes the exploitation of light *** LHSs in nature are sophisticated supramolecular assemblies of chlorophyll molecules that carry out efficient light harvesting through cascade energy transfer *** by nature,scientists have paid much attention to fabricate stepwise LHSs based on assorted supramolecular scaffolds in recent ***-harvesting antennas and energy acceptors can be accommodated in particular scaffolds,which offer great convenience for energy transfer between *** systems not only further mimic photosynthesis,but also demonstrate many potential applications,such as photocatalysis,tunable luminescence,and information encryption,*** this review article,aiming at offering a practical guide to this emerging research field,the introduction of construction strategies towards sequential LHSs will be *** scaffolds are classified and highlighted,including host-guest assemblies,metal-coordination assemblies,as well as bio-macromolecular and other supramolecular scaffolds.

关键词： Light-harvesting system Supramolecular self-assembly Sequential energy transfer Tunable fluorescence FRET

Spectrum Allocation and Protocol Based on Cognitive Acoustic Technique in Underwater Networks

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Transactions of Tianjin University 2016年第4期22卷 339-344页

作者：金志刚李雅婧罗咏梅羊秋玲 school of electronic information engineering Tianjin University school of Computer Science and Technology Tianjin University College of information Science and Technology Hainan University

In this paper, a strategy is developed for spectrum sharing among multiple cognitive users in underwater environment. This strategy requires all nodes to negotiate and reallocate the channels before sending data, and Hungarian method is used to maximize the sharing rewards. Simulation results show that the proposed strategy can avoid collisions between source-destination node pairs, and guarantee that the communication system gets maximum sharing rewards. Both the parameters of POMDP model and the number of available channels have influence on the system sharing rewards, and the rewards will increase when the channels have larger transition probabilities or more channels are available for communication. However, the channels with larger bandwidths can attract more nodes to access, and thus will lead to more collisions.

关键词： underwater sensor network cognitive underwater acoustic communication spectrum sharing Hungarian method

V–L decomposition of a novel full-waveform lidar system based on virtual instrument technique

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Chinese Physics B 2015年第10期24卷 262-273页

作者：徐帆王元庆 school of electronic Science and engineering Nanjing University

A novel three-dimensional（3D） imaging lidar system which is based on a virtual instrument technique is introduced in this paper. The main characteristics of the system include： the capability of modeling a 3D object in accordance with the actual one by connecting to a geographic information system（GIS）, and building the scene for the lidar experiment including the simulation environment. The simulation environment consists of four parts： laser pulse, atmospheric transport,target interaction, and receiving unit. Besides, the system provides an interface for the on-site experiment. In order to process the full waveform, we adopt the combination of pulse accumulation and wavelet denoising for signal *** also propose an optimized algorithm for data decomposition： the V-L decomposition method, which combines Vondrak smoothing and laser-template based fitting. Compared with conventional Gaussian decomposition, the new method brings an improvement in both precision and resolution of data decomposition. After applying V-L decomposition to the lidar system, we present the 3D reconstructed model to demonstrate the decomposition method.

关键词： lidar system virtual instrument Vondrak smoothing laser-template based fitting