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An Intelligent Detection Method for Optical Remote Sensing Images Based on Improved YOLOv7

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Computers, Materials & Continua 2023年第12期77卷 3015-3036页

作者： chao dong Xiangkui Jiang School of Automation Xi’an University of Posts and TelecommunicationsXi’an710121China

To address the issue of imbalanced detection performance and detection speed in current mainstream object detection algorithms for optical remote sensing images,this paper proposes a multi-scale object detection model for remote sensing images on complex backgrounds,called DI-YOLO,based on You Only Look Once v7-tiny(YOLOv7-tiny).Firstly,to enhance the model’s ability to capture irregular-shaped objects and deformation features,as well as to extract high-level semantic information,deformable convolutions are used to replace standard convolutions in the original ***,a Content Coordination Attention Feature Pyramid Network(CCA-FPN)structure is designed to replace the Neck part of the original model,which can further perceive relationships between different pixels,reduce feature loss in remote sensing images,and improve the overall model’s ability to detect multi-scale ***,an Implicitly Efficient Decoupled Head(IEDH)is proposed to increase the model’s flexibility,making it more adaptable to complex detection tasks in various ***,the Smoothed Intersection over Union(SIoU)loss function replaces the Complete Intersection over Union(CIoU)loss function in the original model,resulting in more accurate prediction of bounding boxes and continuous model *** results on the High-Resolution Remote Sensing Detection(HRRSD)dataset demonstrate that the proposed DI-YOLO model outperforms mainstream target detection algorithms in terms of mean Average Precision(mAP)for optical remote sensing image ***,it achieves Frames Per Second(FPS)of 138.9,meeting fast and accurate detection requirements.

关键词： Object detection optical remote sensing images YOLOv7-tiny real-time detection

Arbitrary Decode-Forward Relaying with Re-Encoded Bits Selection Strategy for Polar Codes

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China Communications 2023年第8期20卷 153-162页

作者： Di Guan Kai Niu chao dong Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we propose an arbitrary decode-forward single-relay scheme for finite blocklength polar codes,which can be applied to the general symmetric discrete memoryless relay channel with orthogonal receiver *** relay node decodes the received *** relay node selectively re-encodes the message and transmits it to the destination ***,in order to minimize the upper-bound of the block error probability,we propose a selection strategy to decide the proper re-encoded bit set by the *** results are presented to illustrate the improvement in decoding performance of the proposed scheme compared to conventional relay schemes in both additive white Gaussian noise(AWGN)channel and Rayleigh fading channel(RFC).

关键词： polar codes decode-and-forward relaying arbitrary relay channel block error rate estimation

Sign-changing Solutions to Nonlinear Elliptic Equations with Hardy Potential and Critical Parameter in R^2

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 689-694页

作者： chao-dong XIE Zhi-hui CHEN School of Economics&Management Guizhou University for Ethinic MinoritiesGuizhou 550025China chool of Mathematics South China University of TechnologyGuangzhou 510640China

In this paper,a new Hilbert space is defined which is embedded into W01,q(Ω)for 1≤q<*** using sign-changing critical point theory,we prove the existence of infinitely many sign-changing solutions in this new space f... 详细信息

关键词： elliptic PDE sign-changing solution critical point

A Path Planning Algorithm Based on Improved RRT Sampling Region

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Computers, Materials & Continua 2024年第9期80卷 4303-4323页

作者： Xiangkui Jiang Zihao Wang chao dong College of Automation Xi’an University of Posts and TelecommunicationsXi’an710121China

For the problem of slow search and tortuous paths in the Rapidly Exploring Random Tree(RRT)algorithm,a feedback-biased sampling RRT,called FS-RRT,is proposedbasedon ***,toimprove the samplingefficiency of RRT to shorten the search time,the search area of the randomtree is restricted to improve the sampling ***,to obtain better information about obstacles to shorten the path length,a feedback-biased sampling strategy is used instead of the traditional random sampling,the collision of the expanding node with an obstacle generates feedback information so that the next expanding node avoids expanding within a specific angle ***,this paper proposes using the inverse optimization strategy to remove redundancy points from the initial path,making the path shorter and more ***,to satisfy the smooth operation of the robot in practice,auxiliary points are used to optimize the cubic Bezier curve to avoid path-crossing obstacles when using the Bezier curve *** experimental results demonstrate that,compared to the traditional RRT algorithm,the proposed FS-RRT algorithm performs favorably against mainstream algorithms regarding running time,number of search iterations,and path ***,the improved algorithm also performs well in a narrow obstacle environment,and its effectiveness is further confirmed by experimental verification.

关键词： RRT inversive optimization path planning feedback bias sampling mobile robots

Iterative list decoding approach for Reed-Solomon codes

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The Journal of China Universities of Posts and Telecommunications 2019年第3期26卷 8-14,24页

作者： Zhang Zhijun Niu Kai dong chao Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications

A novel adaptively iterative list decoding(ILD) approach using for Reed-Solomon(RS) codes was investigated. The proposed scheme is exploited to reduce the complexity of RS Chase algorithm(CA) via an iterative decoding attempt mode. In each decoding attempt process, a test pattern is generated by flipping the bits of the least reliable positions(LRPs) within the received hard-decision(HD) vector. The ILD algorithm continues until a test pattern is successfully decoded by the underlying Berlekamp-Massey algorithm(BMA) of RS codes. Flipping within the same bits, the ILD algorithm provides the same test pattern set as the conventional RS CA, thus there is no degradation in error-rate performance. Without decoding all test patterns, the ILD algorithm can simplify the decoding complexity by its early termination. Simulation results show that the average complexity of the ILD algorithm is much lower than that of the conventional RS CA(and is similar to that of BMA decoding) at high signal-to-noise ratio(SNR) region with no less to the RS CA decoding error-rate performance.

关键词： iterative decoding soft-decision decoding Reed-Solomon codes low-complexity decoding

Electron-Electron Collision Term Describing the Reflections Induced Scattering in a Magnetized Plasma

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Chinese Physics Letters 2019年第7期36卷 56-60页

作者： chao dong Ding Li Chang Jiang Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 University of Chinese Academy of Sciences Beijing 100049 Songshan Lake Materials Laboratory Dongguan 523808

For an electron-electron collision with characteristic scale length larger than the relative gyro-radius of the two colliding electrons, when the initial relative parallel kinetic energy cannot surmount the Coulomb repulsive potential, reflection will occur with interchange of the parallel velocities of the two electrons after the collision. The Fokker–Planck approach is employed to derive the electron collision term C_R describing parallel velocity scattering due to the reflections for a magnetized plasma where the average electron gyro-radius is much smaller than the Debye length but much larger than the Landau length. The electron parallel velocity friction and diffusion coefficients due to the reflections are evaluated, which are found not to depend on the electron perpendicular velocity. By studying the temporal evolution of the H quantity due to CR, it is found that C_R eventually makes the system relax to a state in which the electron parallel velocity distribution is decoupled from the perpendicular velocity distribution.

关键词： For an electron-electron scale length larger velocity distribution

Transverse Rutherford Scattering of Electron-Ion Collision in a Uniformly Magnetized Plasma

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Chinese Physics Letters 2022年第2期39卷 43-46页

作者： Chang Jiang chao dong Ding Li Laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Rutherford scattering formula plays an important role in plasma classical *** is urgent to investigate influence of magnetic field on the Rutherford scattering since the high magnetic field has been widely used in nowadays magnetic confinement fusion,inertial confinement fusion,and magneto-inertial *** order to elucidate the magnetic field effect in a concise manner,we study the electron-ion collisions transverse to the magnetic *** scattering angle is defined using the directions of electron velocity before and after collision,which is obtained *** is found that the scattering angle can be influenced by finite magnetic field *** theoretical results agree well with numerical calculation by checking the dependence of scattering angle on the magnetic field.

关键词： field Electron directions

Adaptive synchronization control of uncertain multiple USVs with prescribed performance and preserved connectivity

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Science China(Information Sciences) 2022年第9期65卷 299-300页

作者： Shude HE Shilu DAI chao dong School of Automation Science and Engineering South China University of Technology South China Sea Marine Survey and Technology Center

Dear editor,Cooperative control of multi-vehicle systems has recently received increasing attention from system and control engineering communities owing to its broad applications, such as coordinated exploration, cooperative carrying and cooperative patrolling [1]. A typical topic in this field is synchronization control, whose objective is to design control protocol for each vehicle using the local interaction with its neighbors to synchronize to the (virtual) leader.

关键词： Synchronization tracking control unmanned surface vehicles connectivity preservation prescribed performance adaptive control

Full Quantum Theory of Molecular Hot-Electroluminescence in Scanning Tunneling Microscope Tunnel Junctions

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： Gong Chen Xiao-guang Li Zhen-chao dong International Center for Quantum Design of Functional Materials Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China International Center for Quantum Design of Functional Materials Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 ChinaShenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055China

The pursuit of nanoscale photonics and molecular optoelectronics has stimulated a lot of interests in scanning tunneling microscope(STM) induced molecular emission. In this work, we have introduced a full quantum mechanical approach instead of the previous semiclassical theory to consider the quantized surface plasmon modes in this system. By considering the mutual interactions between a single molecule and the quantized surface plasmon, we have studied the molecular electroluminescence from STMtunnel junctions. Due to the coupling to the surface plasmons, the spontaneous emission rate and the fluorescence intensity of the molecule are both enormously enhanced. In particular, we show that when the radiative decay rate becomes comparable to the vibrational damping rate, hot-electroluminescence can be observed. All these findings are believed to be instructive for further developments of both molecular electronics and photonics.

关键词： Scanning tunneling microscope induced luminescence Master equation Surface plasmon Hot-electroluminescence