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Advanced Electro-active Dry Adhesive Actuated by an Artificial Muscle Constructed from an Ionic Polymer Metal Composite Reinforced with Nitrogen-doped Carbon Nanocages

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Journal of Bionic engineering 2017年第3期14卷 567-578页

作者： Qingsong He Xu Yang Zhongyuan Wang Jin Zhao Min Yu Zhen Hu Zhendong Dai Institute of Bio-inspired Structure and Surface engineering Jiangsu Provincial Key Laboratory of Bionic Functional Materials Col- lege of Astronautics Nanjing University of Aeronautics & Astronautics Nanjing 210016 China college of mechanical and Electrical engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China Key Laboratory of Mesoscopic Chemistry of MOE Jiangsu Provincial Lab for Nanotechnology School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

An advanced electro-active dry adhesive, which was composed of a mushroom-shaped tibrillar dry adhesive array actuated by an Ionic Polymer Metal Composite （IPMC） artificial muscle reinforced with nitrogen-doped carbon nanocages （NCNCs）, was developed to imitate the actuation of a gecko＇s toe. The properties of the NCNC-reinforced Nation membrane, the electro- mechanical properties of the NCNC-reinforced IPMC, and the related electro-active adhesion ability were investigated. The NCNCs were uniformly dispersed in the 0.1 wt% NCNC/Nafion membrane, and there was a seamless connection with no clear interface between the dry adhesive and the IPMC. Our 0.1 wt% NCNC/Nation-IPMC actuator shows a displacement and force that are 1.6 - 2 times higher than those of the recast Nafion-IPMC. This is due to the increased water uptake （25.39%） and tensile strength （24.5 MPa） of the specific 3D hollow NCNC-reinforced Nation membrane, as well as interactions between the NCNCs and the sulfonated groups of the Nation. The NCNC/Nation-IPMC was used to effectively actuate the mushroom-shaped dry adhesive. The normal adhesion forces were 7.85 raN, 12.1 mN, and 51.7 mN at sinusoidal voltages of 1.5 V, 2.5 V, and 3.5 V, respectively, at 0.1 Hz. Under the bionic leg trail, the normal and shear forces were approximately 713.5 mN （159 mN·cm^-2） and 1256.6 mN （279 mN·cm^-2）, respectively, which satisfy the required adhesion. This new electro-active dry adhesive can be applied for active, distributed actuation and flexible grip in robots.

关键词： electro-active dry adhesive bionic ionic polymer metal composite Nation membrane carbon nanocage

Effects of high-order dispersions on dark-bright vector soliton propagation and interaction

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Chinese Optics Letters 2011年第3期9卷 21-24页

作者：李宏王东宁 School of mechanical and electronic engineering Huangshi Institute of Technology college of Physics and electronic Science Hubei Normal University Department of Electrical engineering The Hong Kong Polytechnic University

The dynamics of dark-bright vector solitons is investigated in a birefringent fiber with the high-order dispersions,and their effects on vector soliton propagation and interaction are analyzed using the numerical *** combined role of the high-order dispersions,such as the third-order dispersion （TOD） and the fourth-order dispersion （FOD）,may cause various deformation of the vector soliton and enhance *** effects depend strictly on the sign of the high-order *** indicate that the disadvantageous effects can be reduced effectively via proper mapping of the high-order dispersions.

关键词： Dispersions Numerical methods Solitons Vectors

Bidirectional cascaded deep neural networks with a pretrained autoencoder for dielectric metasurfaces

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Photonics Research 2021年第8期9卷 1607-1615页

作者： WEICHAO KONG JUN CHEN ZENGXIN HUANG DENGFENG KUANG Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology and Institute of Modern OpticsNankai UniversityTianjin 300350China col lege of Physics and electronic engineering Taishan UniversityTaian 271000China

Metasurfaces composed of meta-atoms provide promising platforms for manipulating amplitude,phase,and polarization of ***,the traditional design methods of metasurfaces are time consuming and ***,we propose a bidirectional cascaded deep neural network with a pretrained autoencoder for rapid design of dielectric metasurfaces in the range of 450 nm to 850 *** forward model realizes a prediction of amplitude and phase responses with a mean absolute error of ***,the backward model can retrieve patterns of meta-atoms in an inverse-design *** availability of this model is demonstrated by database establishment,model evaluation,and generalization ***,we try to reveal the mechanism behind the model in a visualization *** proposed approach is beneficial to reduce the cost of computation burden and improve nanophotonic design efficiency for solving electromagnetic on-demand design issues automatically.

关键词： neural networks dielectric

Sensor scheduling for ground maneuvering target tracking in presence of detection blind zone

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Journal of Systems engineering and electronics 2020年第4期31卷 692-702页

作者： XU Gongguo SHAN Ganlin DUAN Xiusheng Department of electronic and Optical engineering Shijiazhuang Campus of Army Engineering UniversityShijiazhuang 050003China School of mechanical engineering Shijiazhuang Tiedao UniversityShijiazhuang 050013China

Continuous and stable tracking of the ground maneuvering target is a challenging problem due to the complex terrain and high clutter. A collaborative tracking method of the multisensor network is presented for the ground maneuvering target in the presence of the detection blind zone(DBZ). First, the sensor scheduling process is modeled within the partially observable Markov decision process(POMDP) framework. To evaluate the target tracking accuracy of the sensor, the Fisher information is applied to constructing the reward function. The key of the proposed scheduling method is forecasting and early decisionmaking. Thus, an approximate method based on unscented sampling is presented to estimate the target state and the multi-step scheduling reward over the prediction time horizon. Moreover, the problem is converted into a nonlinear optimization problem, and a fast search algorithm is given to solve the sensor scheduling scheme quickly. Simulation results demonstrate the proposed nonmyopic scheduling method(Non-MSM) has a better target tracking accuracy compared with traditional methods.

关键词： sensor scheduling ground maneuvering target detection blind zone(DBZ) decision tree optimization

Three-component hybrid-integrated optical accelerometer based on LiNbO_3 photoelastic waveguide

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Chinese Optics Letters 2009年第1期7卷 32-35页

作者：唐东林梁政张晓东何山郭峰 Faculty of mechanical and electronic engineering Southwest Petroleum UniversityKey Laboratory of Petroleum-Gas EquipmentMinistry of Education of China

A novel three-component hybrid-integrated optical accelerometer based on LiNbO3 photoelastic waveguide is presented. The photoelasitcity of LiNbO3 due to three-dimensional stress states is obtained analytically. We analyze the level of sensitivity to cross-axis accelerations which is a very important parameter for three-component accelerometer. Theoretically, the designed three-component hybrid-integrated optical accelerometer has a transverse sensitivity ratio （TSR） of zero. The sensor has a high natural frequency of 3.5 kHz and a linear broad working freauency.

关键词： Optical devices Optical instruments Three dimensional Waveguide couplers Waveguides

Effects of external magnetic trap on two dark solitons of a two-component Bose-Einstein condensate

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Chinese Optics Letters 2008年第8期6卷 611-614页

作者：李宏 D. N. Wang Department of Physics Hubei NormaJ University Huangshi 435002 School of mechanical and electronic engineering Huangshi Institute of Technology Huangshi 435003 Department of Electrical engineering The Hong Kong Polytechnic University Hong Kong

Two dark solitons are considered in a two-component Bose-Einstein condensate with an external magnetic trap, and effects of the trap potential on their dynamics are investigated by the numerical simulation. The results show that the dark solitons attract, collide and repel periodically in two components as time changes, the time period depends strictly on the initial condition and the potential, and there are obvious self-trapping effects on the two dark solitons.

关键词： Bose Einstein condensation Computer simulation Plasma confinement Steam condensers

Comparison of Algorithms for an electronic Nose in Identifying Liquors

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Journal of Bionic engineering 2008年第3期5卷 253-257页

作者： Zhi-biao Shi Tao Yu Qun Zhao Yang Li Yu-bin Lan School of Energy Resources and mechanical engineering Northeast Dianli University Jilin 132012 P. R. China School of Chemistry engineering Northeast Dianli University Jilin 132012 P. R. China School of Electrical engineering Northeast Dianli University Jilin 132012 P. R. China Aerial Application Technlogy usDA-ARS-SPARC-APMRU Co）lege Station TX 77845 USA

When the electronic nose is used to identify different varieties of distilled liquors, the pattern recognition algorithm is chosen on the basis of the experience, which lacks the guiding principle. In this research, the different brands of distilled spirits were identified using the pattern recognition algorithms （principal component analysis and the artificial neural network）. The recognition rates of different algorithms were compared. The recognition rate of the Back Propagation Neural Network （BPNN） is the highest. Owing to the slow convergence speed of the BPNN, it tends easily to get into a local minimum. A chaotic BPNN was tried in order to overcome the disadvantage of the BPNN. The convergence speed of the chaotic BPNN is 75.5 times faster than that of the BPNN.

关键词： electronic nose liquor algorithm principal component analysis

A 7-bit photonic true-time-delay system based on an 8×8 MOEMS optical switch

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Chinese Optics Letters 2009年第2期7卷 118-120页

作者：杨莹董毅柳大伟何浩金耀辉胡卫生 School of electronic Information and Electrical engineering Shanghai Jiao Tong University

We demonstrate a 7-bit photonic true-time-delay （TTD） system which uses an 8 × 8 micro-optical-electro- mechanical system （MOEMS） optical switch for phased array antennas （PAAs） beamforming applications. The switch controls the optical signal to pass by the fiber delay lines （FDLs） of different lengths. Different time delays between adjacent channels are obtained due to the chromatic dispersion of FDLs. Therefore, the system cannot be disturbed by the environment. The measured time delay responses are nearly linear with the wavelength spacing between optical carriers as well as the lengths of FDLs, which agrees well with the theoretical analysis.

关键词： Antenna phased arrays Delay control systems Electromechanical devices Optical switches

Photoluminescence study of the annihilation process of donor-bound excitons in ZnO:observation of quantum mechanical interference

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Chinese Optics Letters 2010年第7期8卷 683-684页

作者：施申蕾黄腾超 Department of Physics China Jiliang University Department of Information Science and electronic engineering Zhejiang University

We report a photoluminescence observation of the coupling of donor-bound excitons and longitudinal optical phonons in high-quality ZnO crystals at 5 K. The first-order phonon Stockes line of donor-bound excitons exhibits a distinct asymmetric line shape with a clear dip at its higher energy side, suggesting that quantum mechanical interference occurs during the annihilation of donor-bound excitons. The donor binding energy is determined to be 49.3 meV from spectral featural.

关键词： Binding energy Phonons Photoluminescence Quantum theory Semiconductor quantum wells Zinc oxide