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改进轻量化 YOLOv7-tiny 道路限高障碍物检测方法

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中国测试 2024年第5期50卷 186-192页

作者：张青春王文聘张洪源张恩溥宁建峰淮阴工学院自动化学院江苏淮安223001

针对道路限高障碍物检测困难、模型复杂以及难以在嵌入式端部署等问题,提出一种基于改进轻量化YOLOv7-tiny模型的道路限高障碍物检测方法。改进模型采用更加轻量的FasterNet网络替换原有主干网络,在Neck层使用PConv卷积替代部分Conv卷积... 详细信息

针对道路限高障碍物检测困难、模型复杂以及难以在嵌入式端部署等问题,提出一种基于改进轻量化YOLOv7-tiny模型的道路限高障碍物检测方法。改进模型采用更加轻量的FasterNet网络替换原有主干网络,在Neck层使用PConv卷积替代部分Conv卷积,以减少计算冗余和内存访问,从而有效降低模型的参数量和计算量。同时,引入CA注意力机制提高检测精度,并使用Focal-EIoU损失函数优化模型的收敛速度和效率。实验结果表明:相较于YOLOv7-tiny目标检测模型,改进模型在检测数据集上,mAP@0.5提高6.6%,参数量和计算量分别降低24%和20.5%,模型权重文件减少27.2%,能够在保持较高检测精度的同时,满足轻量化的需求。

关键词：障碍物检测轻量化 YOLOv7-tiny FasterNet PConv卷积 CA注意力机制

维普期刊数据库博看期刊

Development of chloroplast marker for identification of Ulva species

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Journal of Oceanology and Limnology 2022年第6期40卷 2364-2371页

作者： Dahai GAO qingchun zhang Zhongmin SUN Key Laboratory of Exploration and Utilization of Aquatic Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China Shanghai Engineering Research Center of Aquaculture Shanghai Ocean UniversityShanghai 201306China Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of Sciences(IOCAS)Qingdao 266071China Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Large-scale Ulva-caused green tides has posed various environmental and ecological problems as well as economic *** is important to identify them accurately and *** current universal markers based on ITS,rbc L,and 5S spacer sequences were defective to distinct closely related species in the genus of *** this study,by investigating the intergenic regions of chloroplast(cp)genome,a novel marker of c15(based on ycf 3-rps 7)were reliable for discrimination of Ulva ***,the resolution of c15 was suitable for resolve the closely related species of *** and ***,which may provide tools for deciphering the blooming mechanisms of green tides.

关键词： Ulva linza-procera-prolifera(LPP)complex molecular makers ycf 3-rps 7 region

GA-BASED PID NEURAL NETWORK CONTROL FOR MAGNETIC BEARING SYSTEMS

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Chinese Journal of Mechanical Engineering 2007年第2期20卷 56-59页

作者： LI Guodong zhang qingchun LIANG Yingchun School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

In order to overcome the system non-linearity and uncertainty inherent in magnetic bearing systems, a GA（genetic algnrithm）-based PID neural network controller is designed and trained tO emulate the operation of a complete system （magnetic bearing, controller, and power amplifiers）. The feasibility of using a neural network to control nonlinear magnetic bearing systems with unknown dynamics is demonstrated. The key concept of the control scheme is to use GA to evaluate the candidate solutions （chromosomes）, increase the generalization ability of PID neural network and avoid suffering from the local minima problem in network learning due to the use of gradient descent learning method. The simulation results show that the proposed architecture provides well robust performance and better reinforcement learning capability in controlling magnetic bearing systems.

关键词： Magnetic bearing Non-linearity PID neural network Genetic algorithm Local minima Robust performance

A DAMAGE MECHANICS MODEL FOR FATIGUE LIFE PREDICTION OF FIBER REINFORCED POLYMER COMPOSITE LAMINA

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Acta Mechanica Solida Sinica 2011年第5期24卷 399-410页

作者： Wenjing Shi Weiping Hu Miao zhang qingchun Meng Institute of Solid Mechanics School of Aeronautics Science and Engineering BeiHang University Beijing 100191 China

A damage mechanics fatigue life prediction model for the fiber reinforced polymer lamina is established. The stiffness matrix of the lamina is derived by elastic constants of fiber and matrix. Two independent damage degrees of fiber and matrix are introduced to establish constitutive relations with damage. The damage driving forces and damage evolution equations for fiber and matrix are derived respectively. Fatigue tests on 0° and 90° unidirectional laminates are conducted respectively to identify parameters in damage evolution equations of fiber and matrix. The failure criterion of the lamina is presented. Finally, the life prediction model for lamina is proposed.

关键词： fiber reinforced polymer composite lamina continuum damage mechanics fatigue life prediction fiber breakage matrix cracking

Variations in nano-and pico-eukaryotic phytoplankton assemblages in the Qinhuangdao green-tide area

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Journal of Oceanology and Limnology 2022年第6期40卷 2446-2461页

作者： Weiqian zhang Hongbin HAN Limei QIU Chao LIU qingchun zhang Guizhong ZHOU Qingdao University of Science and Technology Qingdao 266071China CAS and Shandong Province Key Laboratory of Experimental Marine Biology Institute of OceanologyCAS Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China University of Chinese Academy of Sciences Beijing 100049China Center of Ocean Mega Science Chinese Academy of SciencesQingdao 266071China

Qinhuangdao coastal waters have been frequently hitting by nano-and pico-eukaryotic phytoplankton(NPEP)blooms and green tides(macroalgal blooms)in the recent ***,understanding about the impacts of environmental factors and the green tides on the NPEP assemblages in this area is *** this study,the composition of NPEP assemblages and their variations were analyzed via amplicon sequence variants(ASVs)assay based on amplicon high-throughput sequencing data with the 18S V4 region as a targeted gene in the Qinhuangdao green-tide area during the green ***,average NPEP effective sequences and ASVs of 178000 and 200 were obtained from each sample,*** there were 25 classes,110 genera,and 97 species of NPEP were identified and annotated,the proportions of annotated ASVs at genus and species levels were only 44.7%and 17.8%,*** NPEP communities had a seasonal succession from diatom-dominated to *** the three investigations,Skeletonema,Karlodinium,and Gonyaulax were the most dominant genera in May,August,and September,*** diversity and the abundance of NPEP communities could be increased by a high content of dissolved organic nitrogen(DON)and dissolved organic phosphorus(DOP)but inhibited by low dissolved inorganic phosphorus *** outbreak of green tides could alter the composition and content of nutrients and accelerate the succession of the NPEP communities from diatom-dominated to dinoflagellate-dominated under the background of a seasonal increase in seawater *** results preliminarily revealed the impacts of the recurrent occurrences of green tides on the NPEP assemblages in the Qinhuangdao green-tide area exhibiting high DON content and dissolved inorganic nitrogen/phosphorus ratio.

关键词： nano-and pico-eukaryotic phytoplankton high-throughput sequencing green tide eutrophication Qinhuangdao

空间目标捕获遥感器与姿态调整机构的基准建立方法

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光学技术 2024年第4期50卷 425-431页

作者：岳聪张青春杜建祥李文广王大鹏李进北京空间机电研究所北京100094

空间目标捕获遥感器越来越多的应用在深空探测领域中,其配合高精度多维度调整机构可以快速准确对空间目标进行捕捉。捕获遥感器的姿态调整是基于调整机构坐标系进行的,同时为了消除由于捕获遥感器光学基准与调整机构坐标系不一致而导致... 详细信息

空间目标捕获遥感器越来越多的应用在深空探测领域中,其配合高精度多维度调整机构可以快速准确对空间目标进行捕捉。捕获遥感器的姿态调整是基于调整机构坐标系进行的,同时为了消除由于捕获遥感器光学基准与调整机构坐标系不一致而导致的捕获遥感器视场角不对称的影响,捕获遥感器在与调整机构进行安装时,不仅需要测量出光学基准与调整机构坐标系的夹角矩阵,而且还要通过调整使捕获遥感器的光学基准和调整机构的坐标系的空间夹角满足一定的公差要求。文章介绍了一种在同一坐标系下采用激光跟踪仪来同时实现光学基准和机械基准测量的方法,同时建立二者之间的夹角矩阵,再通过电子经纬仪对捕获遥感器的光学基准的实时监测,来实现捕获遥感器与姿态调整机构的精准安装,安装精度可以控制在10″以内。

关键词：光学基准机械基准激光跟踪仪夹角矩阵

A Novel Source Number Estimator Without Complete Eigendecomposition

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A Novel Source Number Estimator Without Complete Eigendecomp...

Mapping the resting cysts of dinoflagellate Alexandrium catenella along the coast of Qinhuangdao,China

2006 8th International Conference on Signal Processing

作者： qingchun zhang Zhenghe Feng Student Member IEEEState Key Laboratory On Microwave And Digital Communication Tsinghua University Senior Member IEEE State Key Laboratory On Microwave And Digital Communication Tsinghua University

ISBN: (纸本)0780397371;9780780397378

＜正＞In this paper,we present another novel source number estimator without the complete eigendecomposition,it is based on the Lanczos process and Sturm algorithm and Finally,for the case of a Uniform Circular Array of six isotropic sensors spaced a half wavelength apart with additive and uncorrelated white noise,we provide a simulated data example to evaluate the proposed estimator,which is proved to be very available.

关键词： Parameter estimation

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Journal of Oceanology and Limnology 2022年第6期40卷 2312-2321页

作者： Wenjiao TANG Huixia GENG Yanjuan XI qingchun zhang Xuexi TANG Rencheng YU College of Marine Life Science Ocean University of ChinaQingdao 266003China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Hebei Academy of Ocean and Fishery Science Qinhuangdao 066200China

Dinoflagellate Alexandrium catenella is a cosmopolitan bloom-forming species with complex life cycle,the formation and germination of resting cysts are critical for its bloom *** the coastal waters of Qinhuangdao,*** has been identified as the major causative agent for paralytic shellfish poisoning,but there is little knowledge concerning its resting cysts in this *** this study,three surveys were carried out along the coast of Qinhuangdao from 2020 to 2021 to map the distribution of *** resting cysts,using a quantitative PCR(qPCR)assay specific for *** resting cysts were detected in surface sediments during all the three surveys,and their distribution patterns were *** abundance of resting cysts(maximum 1300 cysts/g sediment(wet weight))were found in a region(119.62°E-119.99°E,39.67°N-39.98°N)northeast to the coastal waters of Qinhuangdao,where surface sediments were mainly composed of clay and silt(percentage above 50%).Prior to the formation of the *** bloom in March 2021,the abundance of *** vegetative cells in seawater had extremely significant positive correlation with the abundance of resting cysts in surface sediments,reflecting the important role of resting cysts in the initiation of *** *** far as we know,this is the first report on the distribution of *** cysts along the coast of *** results will of fer a sound basis for the future monitoring and mitigation of toxic *** blooms and paralytic shellfish poisoning events in this region.

关键词： harmful algal bloom(HAB) Alexandrium catenella resting cyst paralytic shellfish toxin(PST) Qinhuangdao

基于负二项稀疏算子和推广的负二项稀疏算子的INAR(1)模型的比较

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科学技术创新 2024年第6期 95-98页

作者：赵宸稷张庆春曹晓涵吉林化工学院信息与控制工程学院吉林吉林吉林化工学院理学院吉林吉林

本文利用条件极大似然估计的方法比较利用预设新息分布法基于推广的负二项稀疏算子INAR(1)模型和负二项稀疏算子的INAR(1)模型的参数估计情况。通过对取不同新息项分布的两个模型分别进行数值模拟,并对两个模型数值模拟的结果进行对比... 详细信息

本文利用条件极大似然估计的方法比较利用预设新息分布法基于推广的负二项稀疏算子INAR(1)模型和负二项稀疏算子的INAR(1)模型的参数估计情况。通过对取不同新息项分布的两个模型分别进行数值模拟,并对两个模型数值模拟的结果进行对比来直观地表明由于基于负二项稀疏算子的INAR(1)模型在x=0点时概率质量不存在进而模型的所有边际分布不存在,从而证明利用预设新息分布法基于负二项稀疏算子的INAR(1)模型不存在,也表明推广的负二项稀疏算子在利用预设新息分布法构建INAR(1)模型中的必要性。

关键词：负二项稀疏算子二项稀疏算子 INAR(1)模型条件极大似然估计