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Chinese Journal of Electronics 2024年第3期33卷 803-813页

作者： Yongkui SUN Yuan CAO Peng LI Guo XIE Tao WEN Shuai SU National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University School of Electronic and information Engineering Beijing Jiaotong University Shaanxi key laboratory of Complex System Control and Intelligent information processing Xi'an University of Technology Frontiers Science Center for Smart high-speed Railway System Beijing Jiaotong University

As one of the most important railway signaling equipment,railway point machines undertake the major task of ensuring train operation *** fault diagnosis for railway point machines becomes a hot *** the advantage of the anti-interference characteristics of vibration signals,this paper proposes an novel intelligent fault diagnosis method for railway point machines based on vibration signals.A feature extraction method combining variational mode decomposition(VMD) and multiscale fluctuation-based dispersion entropy is developed,which is verified a more effective tool for feature ***,a two-stage feature selection method based on Fisher discrimination and ReliefF is proposed,which is validated more powerful than single feature selection ***,support vector machine is utilized for fault *** comparisons show that the proposed method performs *** diagnosis accuracies of normal-reverse and reverse-normal switching processes reach 100% and 96.57% ***,it is a try to use new means for fault diagnosis on railway point machines,which can also provide references for similar fields.

关键词： Fault diagnosis Vibrations Support vector machines Diversity reception Switches Feature extraction Rail transportation

On Klein tunneling of low-frequency elastic waves in hexagonal topological plates

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1139-1154页

作者： Yuxin YAO Yuansheng MA Fang HONG Kai ZHANG Tingting WANG Haijun PENG Zichen DENG School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China MIIT key laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an710072China State key laboratory of Structural Analysis for Industrial equipment Dalian University of TechnologyDalian116024Liaoning ProvinceChina

Incident particles in the Klein tunnel phenomenon in quantum mechanics can pass a very high potential *** the concept of tunneling into the analysis of phononic crystals can broaden the application *** this study,the structure of the unit cell is designed,and the low frequency(signal separators and logic gates)are further explored by designing phononic crystal *** research has broad application prospects in information processing and vibration control,and potential applications in other directions are also worth exploring.

关键词： topological metamaterial elastic wave Klein tunneling valley-locked waveguide

A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm

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Chinese Physics B 2024年第7期33卷 233-243页

作者：苏静明方士辉洪炎温言 Anhui Mining Machinery and Electrical equipment Coordination Innovation Center Anhui University of Science and TechnologyHuainan 232001China School of Computer Science and information Engineering Hefei University of TechnologyHefei 230009China

A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc.

关键词： color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling

Multiway Dynamic Trust Chain Model on Virtual Machine for Cloud Computing

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China Communications 2016年第7期13卷 83-91页

作者： Jie Zhu Guoyuan Lin Fucheng You Huaqun Liu Chunru Zhou School of Computer Science and Technology China University of Mining&TechnologyXuzhou 221116China State key laboratory for Novel Software Technology hosted at Nanjing University Nanjing 210093China information Engineering School of beijing Institute of Graphic Communication Beijing 102600China beijing key laboratory of signal and information processing for high-end printing equipment Beijing Institute of Graphic CommunicationBeijing 100026China information Security Center Beijing University of Posts and TelecommunicationsBeijing 100876China Nanjing University of information Science&Technology Nanjing 210044China

This paper sums up four security factors after analyzing co-residency threats caused by the special multitenant environment in the *** secure the factors,a multiway dynamic trust chain transfer model was proposed on the basis of a measurement interactive virtual machine and current behavior to protect the integrity of the system.A trust chain construction module is designed in a virtual machine *** dynamic monitoring,it achieves the purpose of transferring integrity between virtual machine.A cloud system with a trust authentication function is implemented on the basis of the model,and its practicability is shown.

关键词： cloud computing virtual machine trustworthiness measurement dynamic trust transfer

Research on the fractal model and calibration of the aerosol mass concentration measurement based on the particle group light scattering

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Chinese Optics Letters 2016年第11期14卷 104-109页

作者：顾芳刘毅张加宏陈云云崔芬萍 School of Physics and Optoelectronic Engineering Nanjing University of Information Science and Technology School of Electronic & information Engineering Nanjing University of Information Science and Technology Jiangsu Collaborative Innovation Center on Atmospheric Environment and equipment Technology Nanjing University of Information Science and Technology Jiangsu key laboratory of Meteorological Observation and signal processing Nanjing University of Information Science and Technology

In order to improve the inversion precision ot aerosol mass concentrations based on the particle group light scattering method,the concept that particles through a laser beam are equivalent to an aggregate is proposed.A fractal model for aerosol mass concentration using the signal amplitude distribution of aggregates is presented,and then the subsection calibration method is *** experimental results show that the mass concentrations in versed by this model agree well with those measured by the norm-referenced *** average relative errors of the two experiments are 5.6%and 6.0%,respectively,which are less than those obtained by the conventional inversion model.

关键词： Aerosols Aggregates Calibration Fractals Laser beams

Finite-horizon resilient state estimation for complex networks with integral measurements from partial nodes

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Science China(information Sciences) 2022年第3期65卷 167-181页

作者： Nan HOU Jiahui LI Hongjian LIU Yuan GE Hongli DONG Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial key laboratory of Networking and Intelligent Control Northeast Petroleum University key laboratory of Advanced Perception and Intelligent Control of high-end equipment Ministry of EducationAnhui Polytechnic University School of Electrical Engineering Anhui Polytechnic University

This paper proposes a finite-horizon state estimation method for a kind of complex network that suffers from randomly occurring gain variations. The method involves utilizing integral measurements from a portion of nodes in such complex networks. Integral measurements are carried out to characterize time delays that occur in signal acquisition together with real-time signal processing. Measurements from only partial nodes reflect the fact that signals of several sensors are unacquirable. A Gaussian random variable is utilized to depict the random appearance of gain variations during the practical implementation of estimators. The aim of this paper is to construct finite-horizon resilient estimators for complex networks in view of integral measurements from a portion of nodes that fulfill the specified H∞ performance demand involving a specified disturbance attenuation level. Necessary and sufficient conditions are put forward to ensure that such ideal estimators exist by employing stochastic analysis as well as using the completing squares method. The gain parameters of the finite-horizon estimators are expressed by adopting the Moore-Penrose pseudoinverse and acquired through solving the solutions to a group of coupled backward recursive Riccati difference equations with constraint conditions. A confirmatory instance is carried out that demonstrates the feasibility of the newly developed estimation algorithm.

关键词： complex networks finite-horizon $H_{\infty}$ partial-nodes-based state estimation gain variations backward recursive Riccati difference equations integral measurements

An E-type Temperature Sensor for Upper Air Meteorology

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Nanotechnology and Precision Engineering 2018年第2期1卷 145-149页

作者： Shangbang Han Qingquan Liu Xu Han Wei Dai Jie Yang School of Electronic and information Engineering Nanjing University of Information Science and TechnologyNanjing 210044China Jiangsu key laboratory of Meteorological Observation and signal processing Nanjing 210044China Jiangsu Collaborative Innovation Center on Atmospheric Environment and equipment Technology Nanjing 210044China key laboratory of MEMS of Ministry of Education Southeast UniversityNanjing 210096China

An E-type high-precision temperature sensor, which is adopted for upper air meteorology, was proposed in this paper. A computational fluid dynamics(CFD) method was implemented to analyze temperature rise induced by solar radiation at different altitudes and solar radiation intensities. A temperature rise correction equation was obtained by fitting the CFD results using a Broyden-Fletcher-Goldfarb-Shanno(BFGS) method. To verify the performance of the temperature sensor, an experimental platform was constructed. Through simulations and experiments, the relationship among the altitude, solar radiation intensity and radiation temperature rise was obtaned. The root-mean-square error(RMSE) between the temperature rise derived from the correction equation and that derived from the experiments is 0.013 K. The sample determination coefficient r2 of the solar radiation error correction equation is 0.9975.

关键词： high-precision temperature sensor Computational fluid dynamics Radiation temperature

A New Finite Element Model with Manufactured Error for Additive Manufacturing

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Computer Modeling in Engineering & Sciences 2020年第8期124卷 703-720页

作者： Zhaohui Xia Zhihao He Qifu Wang Yingjun Wang National Enterprise information Software Engineering Research Center School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China National Engineering Research Center of Novel equipment for Polymer processing The Key Laboratory of Polymer Processing Engineering of the Ministry of Education(South China University of Technology)Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSouth China University of TechnologyGuangzhou510641China

Additive manufacturing(AM),adding materials layer by layer,can be used to produce objects of almost any shape or ***,AM techniques cannot accurately build parts with large overhangs,especially for the large features close to horizontal,hanging over the *** overhangs will make the manufactured model deviate from the design model,which will result in the performance of the manufactured model that cannot satisfy the design *** this paper,we will propose a new finite element(FE)analysis model that includes the manufacturing errors by mimicking the AM layer by layer construction *** such FE model,an overhang coefficient is introduced to each FE,which is defined by the support elements in the lower *** mimicking the AM process from the bottom layer to the top layer,all the FE properties are updated based on their overhang coefficients,which makes the computational model be able to predict the manufactured model with manufacturing *** proposed model can be used to predict the performance of the AM objects in the design stage,which will help the designers to improve their design by the simulation results.

关键词： Additive manufacturing manufacturing error finite element analysis overhangs 3D printing

Gradient-crosslinked hydrogel microdome pattern for multilevel chromatic encryption

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Science China Chemistry 2023年第12期66卷 3567-3575页

作者： Jing Xue Yu Wang Tailong Zhang Kaixuan Li Florian Vogelbacher Yu Zhang Xiaoyu Hou Zixin Zhu Yang Tian Yanlin Song Mingzhu Li key laboratory of Green printing Institute of ChemistryChinese Academy of SciencesBeijing 100190China key laboratory of Bionic Materials and Interface Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China beijing key laboratory for Optical Materials and Photonic Devices Department of ChemistryCapital Normal UniversityBeijing 100048China

In the realm of modern cryptography and anti-counterfeiting,innovative approaches are crucial to encode sensitive information *** responsive structural colors have garnered significant interest due to their feature-rich spectra and high sensitivity to external ***,high costs and complex processing involved in integrating the various delicate microstructures have impeded their widespread *** this study,we present a straightforward multilevel chromatic encryption scheme utilizing direct-writing gradient-crosslinked *** solvent-responsive structural color of each microdome,arising from the synergistic effect of total internal reflections and interference,is adjusted independently across the entire visible *** microdome functions as a signal recording unit,enabling multilevel color variations through a solventdependent development *** approach facilitates the encoding of enhanced information into a single *** demonstrate the efficacy of our method for advanced applications,we have prepared a collection of solvent-dependent multilevel codes for algorithm cryptography,showcasing its potential for high-level anti-counterfeiting and high-density optical data storage.

关键词： oxygen inhibition structural color direct writing encryption storage capacity

Development of a portable multi-channel system for plant physiological signal recording

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information processing in Agriculture 2016年第2期3卷 124-132页

作者： Ting Li Zi-Yang Wang Dong-Jie Zhao Lan Huang Zhong-Yi Wang College of information and Electrical Engineering China Agricultural UniversityBeijing 100083China Modern Precision Agriculture System Integration Research key laboratory of Ministry of Education Beijing 100083China key laboratory of Agricultural information Acquisition Technology(beijing) Ministry of AgricultureBeijing 100083China

Bioelectrical signals can reflect physiological state of organs or tissues in plants and have a significant potential value in research of plant stress *** order to study the relationship between environment factors and electrical signals in plant,a portable multichannel physiological signal acquisition system which relevant in plant physiology research was *** parameters and electrical signals can be measured in different channels by the acquisition system simultaneously and the measurement data will be displayed in an embedded integrated touch screen which is the system processing *** system was validated to be stable and reliable after the calibration and repeated experiments of recording electrical signals in Helianthus annuus L.

关键词： Bioelectrical signals Acquisition system Multi-channel Portable device