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Lightweight Object Detection Networks for UAV Aerial Images Based on YOLO

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Chinese Journal of Electronics 2024年第04期33卷 997-1009页

作者： Yanshan LI Jiarong WANG Kunhua ZHANG Jiawei YI Miaomiao WEI Lirong ZHENG weixin xie ATR National Key Laboratory of Defense Technology Shenzhen University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen University

Existing high-precision object detection algorithms for UAV(unmanned aerial vehicle) aerial images often have a large number of parameters and heavy weight, which makes it difficult to be applied to mobile *** propose three YOLO-based lightweight object detection networks for UAVs, named YOLO-L, YOLO-S, and YOLO-M, respectively. In YOLO-L, we adopt a deconvolution approach to explore suitable upsampling rules during training to improve the detection accuracy. The convolution-batch normalization-Si LU activation function(CBS)structure is replaced with Ghost CBS to reduce the number of parameters and weight, meanwhile Maxpool maximum pooling operation is proposed to replace the CBS structure to avoid generating parameters and weight. YOLO-S greatly reduces the weight of the network by directly introducing CSPGhost Neck residual structures, so that the parameters and weight are respectively decreased by about 15% at the expense of 2.4% mAP. And YOLO-M adopts the CSPGhost Neck residual structure and deconvolution to reduce parameters by 5.6% and weight by 5.7%, while m AP only by 1.8%. The results show that the three lightweight detection networks proposed in this paper have good performance in UAV aerial image object detection task.

关键词： Training YOLO Deconvolution Accuracy Object detection Autonomous aerial vehicles Feature extraction

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Corrosion and in vitro cytocompatibility investigation on the designed Mg-Zn-Ag metallic glasses for biomedical application

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Journal of Magnesium and Alloys 2024年第4期12卷 1566-1580页

作者： Jian Wang Lingzhong Meng weixin xie Chen Ji Ronghua Wang Pinghu Zhang Liling Jin Liyuan Sheng Yufeng Zheng School of Mechanical Engineering Yangzhou UniversityYangzhou225127China Department of Materials Science and Engineering Seoul National UniversitySeoulSouth Korea Huizhou Port Customs Huizhou516081China Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Institute of Translational MedicineMedical CollegeYangzhou UniversityYangzhou225009China Center for Research in Computational Thermochemistry(CRCT) Department of Chemical EngineeringEcole polytechnique de MontréalMontréalQuébecH3C 3A7Canada Shenzhen Institute Peking UniversityShenzhen 518057China PKU-HKUST ShenZhen-HongKong Institution Shenzhen518057China

In the present work,seven Mg-Zn-Ag alloys with the nominal composition of Mg_(96-x)Zn_(x)Ag_(4)(x=17,20,23,26,29,32,35 in at.%)were prepared by induction melting and single-roller *** X-ray diffraction(XRD)analyses indicate the metallic glasses with three composition of Mg_(73)Zn_(23)Ag_(4),Mg_(70)Zn_(26)Ag_(4),and Mg_(67)Zn_(29)Ag_(4)were obtained *** differential scanning calorimetry(DSC)measurement was used to obtain the characteristic temperature of Mg-Zn-Ag metallic glasses for the glass-forming ability *** maximum glass transition temperature(Trg)was found to be 0.525 with a composition close to Mg_(67)Zn_(29)Ag_(4),which results in the best glass-forming ***,the immersion test in simulated body fluid(SBF)demonstrate the relative homogeneous corrosion behavior of the Mg-Zn-Ag metallic *** corrosion rate of Mg-Zn-Ag metallic glasses in SBF solution decreases with the increase of Zn *** sample Mg_(67)Zn_(29)Ag_(4)has the lowest corrosion rate of 0.19mm/yr,which could meet the clinical application requirement *** in vitro cell experiments show that the Madin-Darby canine kidney(MDCK)cells cultured in sample Mg_(67)Zn_(29)Ag_(4)and its extraction medium have higher ***,the Mg-Zn-Ag metallic glasses exhibit obvious inhibitory effect on human rhabdomyosarcoma(RD)tumor *** present investigations on the glass-forming ability,corrosion behavior,cytocompatibility and tumor inhibition function of the Mg-Zn-Ag based metallic glass could reveal their biomedical application possibility.

关键词： Metallic glasses Mg-Zn-Ag Corrosion behavior In vitro cytocompatibility

A double-layer radiative cooling coating that utilizes the refractive index difference between layers to achieve extremely high solar reflectivity

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Science China Technological Sciences 2024年第10期67卷 3182-3189页

作者： WANG FuQiang LI ChunZhe YANG ZhenNing xie weixin LI Xiang XU ZengHui YAN YuYing CHENG ZiMing School of Energy Science and Engineering Harbin Institute of Technology School of New Energy Harbin Institute of Technology at Weihai China Construction Eco-Environmental Protection Technology Co. Ltd. Faculty of Engineering University of Nottingham

Passive daytime radiative cooling（PDRC） technology has great potential in reducing cooling energy consumption. In order to further improve the spectral performance of PDRC coatings, current researchers mostly focus on the selection and size design of functional particles, while ignoring the optical properties enhancement effect caused by the interlayer binder. In this study, based on the principle that the refractive index difference between layers enhanced the backscattering performance of the solar spectrum, we proposed and manufactured a double-layer PDRC coating with polyvinylidene difluoride（PVDF） as the filmforming material in the upper layer and polydimethylsiloxane（PDMS） as the film-forming material in the lower layer, both filled with Al2O3and SiO2particles. The double-layer PDRC coating exhibited excellent spectral performance that a high solar reflectivity of 98% and an emissivity of 0.95 at the “atmospheric window” band. In comparison, the solar spectrum reflectivity of the single-layer PDRC coatings based on PVDF and PDMS of the same thickness was 95% and 94.7%, respectively. Outdoor tests showed that the PDRC coating achieved a temperature decrease of up to 7.1℃ under direct sunlight at noon time. In addition, the PDRC coating had excellent weather resistance, water resistance, and other basic properties. This article opens up a new idea and provides methodological guidance for the design of double-layer PDRC coatings.

关键词： double-layer radiative cooling coating spectral modulation interlayer refractive index solar energy radiative transfer

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Constrained Unscented Kalman Filtering for Bearings-Only Maneuvering Target Tracking

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Chinese Journal of Electronics 2020年第3期29卷 501-507页

作者： ZHANG Hongwei xie weixin Sun Yat-sen University ATR Key Laboratory Shenzhen University

To track the bearings-only maneuvering target tracking accurately online, the soft measurement constraints are implemented into the Unscented Kalman filtering(UKF). To deal with the soft measurement constraints, the Lasso regularization is added as the obstacle function. In doing this, the sampled sigma points can be restricted into the feasible region. To enhance the sampling efficiency, the global optimal solution is acquired by a heuristic optimizer. To smooth the outliers,the posterior distribution is approximated by a Gaussian mixture consists of the original and the modified priors with the fuzzy weighted factor. Simulated results indicate the accuracy and the computational efficiency of the proposed method.

关键词： Bearings-only maneuvering target tracking Soft measurement constraints Optimal

多元治理理论下社区教育助推社会治理研究——基于嵌入式学习点建设的实践

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中国成人教育 2024年第4期 41-49页

作者：谢维新汪梦上海市长宁区业余大学(上海开放大学航空运输学院) 上海200336

一直以来,社区教育发挥着提升公民素养、促进社会发展等重要的社会治理功能。在社会治理逐步转向网格化管理、精细化服务的背景趋势下,上海的“15分钟社区生活圈”建设描绘了社会治理的新图景,其中“宜学”的目标场景呼唤社区教育的参... 详细信息

一直以来,社区教育发挥着提升公民素养、促进社会发展等重要的社会治理功能。在社会治理逐步转向网格化管理、精细化服务的背景趋势下,上海的“15分钟社区生活圈”建设描绘了社会治理的新图景,其中“宜学”的目标场景呼唤社区教育的参与。在社区教育资源存量不足的当下,社区教育网络建设逐渐衍生出嵌入式学习点这类新的建设范式,并呈现出社区教育资源与社区原有点位相互融合、互为需求的特点。文章基于上海嵌入式学习点的建设实践,运用多元治理理论,来思考社区教育助推社会治理问题。

关键词：社会治理多元治理嵌入式学习点社区教育

Constrained auxiliary particle filtering for bearings-only maneuvering target tracking

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Journal of Systems Engineering and Electronics 2019年第4期30卷 684-695页

作者： ZHANG Hongwei xie weixin Automatic Target Recognition Key Laboratory Shenzhen University

To track the nonlinear,non-Gaussian bearings-only maneuvering target accurately online,the constrained auxiliary particle filtering(CAPF)algorithm is *** restrict the samples into the feasible area,the soft measurement constraints are implemented into the update routine via the1 ***,to enhance the sampling diversity and efficiency,the target kinetic features and the latest observations are involved into the *** take advantage of the past and the current measurement information simultaneously,the sub-optimal importance distribution is constructed as a Gaussian mixture consisting of the original and modified priors with the fuzzy weighted *** a result,the corresponding weights are more evenly distributed,and the posterior distribution of interest is approximated well with a heavier *** results demonstrate the validity and superiority of the CAPF algorithm in terms of efficiency and robustness.

关键词： bearings-only maneuvering target tracking soft measurement constraints constrained auxiliary particle filtering(CAPF)

Labeled Multi-Bernoulli Maneuvering Target Tracking Algorithm via TSK Iterative Regression Model

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Chinese Journal of Electronics 2022年第2期31卷 227-239页

作者： WANG Xiaoli xie weixin LI Liangqun Department of Electronics and Information Guangdong Polytechnic Normal University Automatic Target Recognition (ATR) Key Laboratory Shenzhen University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen University

Aiming at the problem that the existing labeled multi-Bernoulli(LMB) method has a single and fixed model set, an LMB maneuvering target tracking algorithm via Takagi-Sugeno-Kang(TSK) iterative regression multiple model is proposed. In the TSK iterative regression modeling, the feature information of the targets is analyzed and represented by multiple semantic fuzzy sets. Then the state is expanded to introduce model information, thereby the adaptive multi-model idea is incorporated into the framework of the LMB method to solve the uncertain maneuverability of moving targets. Finally,the simulation results show that the proposed algorithm can effectively achieve maneuvering target tracking in the nonlinear system.

关键词： Takagi-Sugeno-Kang Iterative regression model Labeled multi-bernoulli Maneuvering target tracking

TGSIFT: Robust SIFT Descriptor Based on Tensor Gradient for Hyperspectral Images

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Chinese Journal of Electronics 2020年第5期29卷 916-925页

作者： LI Yanshan FAN Leidong xie weixin ATR National Key Lab.of Defense Technology Shenzhen University Guangdong Key Laboratory of Intelligent Information Processing College of Information Engineering Shenzhen University

This paper proposes a robust sparse descriptor based on tensor theory by using the spatial and spectral information synthetically, namely the Tensor gradient SIFT(TGSIFT), for Hyperspectral image(HSI).TGSIFT integrates both spatial and spectral information and considers the natural vector feature of HSIs. Based on the HSI Gaussian scale space, a new tensor model for HSI is proposed which takes the vectorial nature of HSI into consideration and preserves all the necessary structural information distributed over all the *** TGSIFT descriptor is formed based on the model proposed. Experimental results of HSI matching show that the TGSIFT descriptor achieves better matching performance than other SIFT descriptors under different transformations, including illumination change, sensor noise, image rotation, viewpoint change, and scale change.

关键词： Hyperspectral image (HSI) Interest points Scale-invariant feature transform (SIFT) Sparse descriptor Tensor gradient SIFT (TGSIFT)

New computing method of weighted coefficients for tracking a maneuvering target using PDAF in the presence of clutter

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Journal of Systems Engineering and Electronics 2009年第5期20卷 968-973页

作者： Liu Zongxiang xie weixin Huang Jingxiong Coll. of Information and Engineering Shenzhen Univ. Shenzhen 518060 P. R. China

To avoid or reduce the influence of unpredictable motion mode on data association, a new computing method of weighted coefficients of measurements for PDAF is presented in which it is assumed that the current turn rate of a maneuvering target changes within a limited range and its turn may be in arbitrary direction during data association. Thus, the predicted center for computing the weighted coefficients is a curved surface in 3-D space, which differs from the predicted center for setting up a validation gate, namely, a point in 3-D space. The distance between a measurement and the curved surface is used to compute its weighted coefficient. To reduce the computational complexity of weighted coefficients, the formulas for computing the maneuvering direction angle and turn rate corresponding to a measurement are presented. Simulation results show the proposed method reduces the percentage of lost tracks and improves the state estimation accuracy in tracking a maneuvering target using PDAF in the presence of clutter.

关键词： target tracking maneuvering target data association weighted coefficient.