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基于改进YOLOv8的自动驾驶场景目标检测算法

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计算机工程与应用 2025年第1期61卷 131-141页

作者：杨磊陈艳菲李海鸣石教兴安培武汉工程大学光学信息与模式识别湖北省重点实验室武汉430205 武汉工程大学电气信息学院武汉430205 华中科技大学电子信息与通信学院武汉430074

针对自动驾驶场景遮挡目标和小目标检测困难问题,提出了FAN-YOLOv8n自动驾驶检测算法。设计了特征感受野融合模块(EFFVM),增强模型主干部分对局部特征的提取,提高模型对遮挡目标的检测能力;在模型头部增加了更浅特征层P2的检测头,提高... 详细信息

针对自动驾驶场景遮挡目标和小目标检测困难问题,提出了FAN-YOLOv8n自动驾驶检测算法。设计了特征感受野融合模块(EFFVM),增强模型主干部分对局部特征的提取,提高模型对遮挡目标的检测能力;在模型头部增加了更浅特征层P2的检测头,提高模型对于小目标的检测效果;在模型颈部设计了特征指导模块(FGM)来融合浅层和深层的特征信息,使得两层之间能够更好地进行特征交互,让模型更关注细粒特征。提出了特征层融合模块(FLFM),融合多尺度特征层并进行特征增强,使模型能够自适应不同尺度目标的检测。实验结果表明,在SODA10M数据集和部分BDD100K数据集上,改进模型的mAP0.5对比原始YOLOv8n模型提升了7个百分点和6.5个百分点,适用于实际自动驾驶检测任务。

关键词：自动驾驶 YOLOv8n 小目标遮挡目标

An Inner Product Formula on Two-dimensional Complex Hyperbolic Space

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Acta Mathematica Sinica,English Series 2011年第11期27卷 2285-2300页

作者： lei yang Department of Mathematics Peking University Beijing 100871 P. R. China

We study the Eisenstein series for a convex cocompact discrete subgroup on a two-dimen- sional complex hyperbolic space Hc^2. We find an inner product formula which gives the connection between Eisenstein series and automorphic Green functions on a two-dimensional complex hyperbolic space HC^2. As an application of our inner product formula, we obtain the functional equations of Eisenstein series.

关键词： Eisenstein series automorphic Green functions functional equations

Equidistribution of Expanding Translates of Curves in Homogeneous Spaces with the Action of(SO(n,1))^(k)

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Acta Mathematica Sinica,English Series 2022年第1期38卷 205-224页

作者： lei yang College of Mathematics Sichuan UniversityChengdu 610000P.R.China

Let X=G/Γbe a homogeneous space with ambient group G containing the group H=(SO(n,1))^(k)and x∈X be such that Hx is dense in *** an analytic curve?:I=[a,b]→H,we will show that ifφsatisfies certain geometric condition,then for a typical diagonal subgroup A={a(t):t∈R}■H the translates{a(t)?(I)x:t>0}of the curve?(I)x will tend to be equidistributed in X as t→+∞.The proof is based on Ratner's theorem and linearization technique.

关键词： Equidistribution homogeneous spaces Ratner's theorem

冲击点火反应过程中RDX基PBX炸药的热辐射特性

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高压物理学报 2025年第1期39卷 44-52页

作者：施鑫辉杨雷杨雪康洪亮袁文硕刘福生西南交通大学物理科学与技术学院高温高压物理研究所四川成都610031

研究冲击波流场中聚合物黏结炸药的热辐射特性可能是获取相关物质组分温度数据的重要途径。利用二级轻气炮加载技术、瞬态辐射测温方法及粒子速度剖面测量技术,探讨了聚合物黏结炸药/氟化锂窗口界面的热辐射特性及其与界面压力之间的相... 详细信息

研究冲击波流场中聚合物黏结炸药的热辐射特性可能是获取相关物质组分温度数据的重要途径。利用二级轻气炮加载技术、瞬态辐射测温方法及粒子速度剖面测量技术,探讨了聚合物黏结炸药/氟化锂窗口界面的热辐射特性及其与界面压力之间的相关性;同时,还优化了聚合物黏结炸药样品制备方法,显著抑制了包裹气体和界面间隙发光背景,给出了界面辐亮度数据及界面温度数据。结果表明,在连续2次冲击加载过程中,界面温度随时间衰减特征与反应产物的等熵膨胀行为密切相关,界面温度反映了界面处产物温度的演化行为,为直接观测点火反应和起爆释能期间非均质复合炸药的反应产物温度数据提供了一种可行的技术途径。

关键词：聚合物黏结炸药冲击加载界面热辐射点火反应等熵膨胀界面温度

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经皮椎体成形联合椎弓根强化治疗重度骨质疏松性椎体骨折的有限元分析

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中国组织工程研究 2025年第15期29卷 3089-3094页

作者：李红桃潘泓宇雷杨肖常明西南医科大学附属中医医院脊柱外科四川省泸州市646000

背景:椎弓根内骨水泥灌注联合椎体成形已被用于治疗Kummell病和椎弓根溶骨性转移瘤等疾病,但该手术方式对相邻椎体及椎间盘的影响尚不明确。目的:应用三维有限元模型探讨经皮椎体成形联合椎弓根强化术治疗重度骨质疏松性椎体骨折对邻近... 详细信息

背景:椎弓根内骨水泥灌注联合椎体成形已被用于治疗Kummell病和椎弓根溶骨性转移瘤等疾病,但该手术方式对相邻椎体及椎间盘的影响尚不明确。目的:应用三维有限元模型探讨经皮椎体成形联合椎弓根强化术治疗重度骨质疏松性椎体骨折对邻近节段椎体以及椎间盘相关生物力学的影响。方法:选择1位已完成经皮椎体成形联合椎弓根强化术的重度骨质疏松性椎体骨折(L1)女性患者,并提取其术前及术后的CT文件,研究范围为T_(12)-L_(2)(包括伤椎、邻近椎体和椎间盘)。通过Mimics、SolidWorks和Geomagic等软件分别建立了术前、术后三维脊柱功能单元的有限元模型。在T_(12)上终板垂直方向加载500 N力矩和10 N·m旋转力矩,模拟前屈、后伸、侧屈和旋转等运动方位,分析手术前后相邻节段椎体终板和椎间盘的应力变化情况。结果与结论:①成功建立了术前和术后脊柱功能单元的三维有限元模型;②通过计算得出,在模拟载荷下,术后T_(12)下终板应力分布更均匀且最大应力值减小,与术前相比无显著差异(P>0.05);术后L_(2)上终板应力分布更均匀且最大应力与术前无显著差异(P>0.05);同样,术后T_(12)/L_(1)、L_(1)/L_(2)椎间盘应力分布也更均匀且最大应力值均显著减小(P<0.05);③因此,经皮椎体成形联合椎弓根强化能够有效改善术后相邻椎体终板和椎间盘的应力分布,并能够减小应力,最终降低术后再骨折风险以及显著延缓椎间盘退变。

关键词：椎弓根强化骨质疏松性椎体骨折椎体成形应力有限元模型骨水泥

A closed nuclear energy system by accelerator-driven ceramic reactor and extend AIROX reprocessing

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Science China(Technological Sciences) 2017年第11期60卷 1702-1706页

作者： yang lei ZHAN WenLong Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

For the future energy system, we propose a new closed nuclear energy cycle system, which consists of an accelerator-driven external neutron source, a ceramic reactor and an extend AIROX reprocessing. The attractive features of this system are as follows. （l） The operating mode of the reactor is a combination of subcritical mode and critical mode. initially, the reactor would be driven by the accelerator external neutron source in subcritical mode. A few years later, the reactor would reach the critical mode, and then would operate for a long time. （2） Nuclear fuels, coolants, and structure materials in the ceramic reactor core are made up of ceramic with excellent thermodynamics properties and neutron performance. Therefore, the ceramic reactor has extremely inherent safety, good breeding performance and high power generation efficiency. （3） Fuel reprocessing uses an extend AIROX reprocessing, which is a simple high-temperature dry process and rarely involved in chemical process. In this reprocessing, only most of fission products are separated. Other isotopes, including uranium isotopes, transuranic nuclides and long-lived fission products, would re-enter the reactor as new fuels. Therefore, this closed nuclear energy system could be known as ADANES, short for Accelerator-Driven Advanced Nuclear Energy System, which can greatly improve the utilization rate of nuclear fuels, enhance the nuclear safety, reduce the nuclear proliferation and become a sustainable and low-carbon energy supply for thousands of years.

关键词： accelerator-driven neutron source ceramic reactor extend AIROX reprocessing closed nuclear energy system future energy system

An Analysis of Piezomagnetic-Piezoelectric Semiconductor Unimorphs in Coupled Bending and Extension under a Transverse Magnetic Field

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Acta Mechanica Solida Sinica 2021年第5期34卷 743-753页

作者： lei yang Jianke Du Ji Wang Jiashi yang Piezoelectric Device Laboratory School of Mechanical Engineering and MechanicsNingbo UniversityNingbo315211China Department of Mechanical and Materials Engineering The University of Nebraska-LincolnLincolnNE68588-0526USA

We study the response of a composite beam(unimorph)with a piezomagnetic layer and a piezoelectric semiconductor layer under a transverse magnetic field.A one-dimensional model for coupled bending and extension of the beam is derived from the three-dimensional theory.A simple and analytical solution of the model is obtained,showing that various electromechanical fields develop in the beam through piezomagnetic and piezoelectric couplings as well as *** particular,the mobile charges in the semiconductor layer redistribute themselves under the magnetic field.A coupling coefficient is defined to describe the strength of this magneto-semiconduction *** effects of physical and geometric parameters on the fields and the coupling coefficient are *** results are fundamental to piezotronics when magnetic effects are involved.

关键词： Piezomagnetic Piezoelectric Semiconductor Unimorph

New concept for ADS spallation target: Gravity-driven dense granular flow target

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Science China(Technological Sciences) 2015年第10期58卷 1705-1711页

作者： yang lei ZHAN WenLong Institute of Modern Physics Chinese Academy of Sciences

For the Chinese-ADS project, to provide enough neutrons to drive the subcritical system, tens of MW spallation targets for the C-ADS are necessary. This is not an easy task. Here we propose a new concept for a gravity-driven dense granular flow target, in which heavy metal grains are chosen as the spallation target material. Compared with currently widely used targets, this conceptual design has advantages with regard to heat removal, thermal shock protection, neutron yield, radiotoxicity reduction, and convenient operation. The gravity-driven dense granular flow target has the potential to easily deal with these issues and to form a foundation for tens of MW spallation targets for cost-effective facilities. Preliminary simulations and experiments have been completed to support this conceptual design.

关键词： accelerator driven system spailation target dense granular flow

Outsourcing or Not? The OEMrs Better Collecting Mode under Cap-and-Trade Regulation

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Journal of Systems Science and Systems Engineering 2021年第2期30卷 151-177页

作者： lei yang Caixia Hao Yijuan Hu Department of Electronic Business South China University of TechnologyGuangzhou 510006China Guangzhou Automobile Group Motor CO. LTDGuangzhou 511434China

Many original equipment manufacturers(OEMs)carry out collecting operations by themselves or a third *** of the existing research papers in the literature consider the collecting mode selection problem from an economic ***,in practice,the firm's collecting decisions can be affected by the carbon policies at *** paper aims to bridge the gap in research on remanufacturing supply chain by taking the effects of cap-and-trade regulation into *** models are established to study the quantity and price decisions under different collecting *** find that the OEM reaps more profits in the OEM collecting mode than the third-party collecting mode when collection cost is ***,the third party has lower collection cost,and the third-party collecting mode may make the OEM more *** an environmental perspective,with high collection cost,the third party collecting mode can reduce the carbon emissions unless the cost of new products and the emissions intensity are *** addition,when the collection cost is low but the quantity of remanufacturing products is restricted by that of new products,the third party collecting mode may increase the carbon *** addition,the implementation of cap-and-trade regulation can always reduce carbon emissions,and it may increase the OEM's profits if consumers preference for remanufactured products is small.

关键词： Remanufacturing collection decision carbon emissions cap-and-trade regulation