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Polymerized-ionic-liquid-based solid polymer electrolyte for ultra-stable lithium metal batteries enabled by structural design of monomer and crosslinked 3D network
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作者 Lingwang Liu Jiangyan Xue +14 位作者 Yiwen Gao Shiqi Zhang Haiyang Zhang Keyang Peng Xin Zhang Suwan Lu Shixiao Weng Haifeng Tu Yang Liu Zhicheng Wang Fengrui Zhang Daosong Fu Jingjing Xu Qun Luo Xiaodong Wu 《Materials Reports(Energy)》 2025年第1期61-69,共9页
Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials ... Solid polymer electrolytes(SPEs)have attracted much attention for their safety,ease of packaging,costeffectiveness,excellent flexibility and stability.Poly-dioxolane(PDOL)is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes(LMAs)and suitability for in-situ polymerization.However,poor thermal stability,insufficient ionic conductivity and narrow electrochemical stability window(ESW)hinder its further application in lithium metal batteries(LMBs).To ameliorate these problems,we have successfully synthesized a polymerized-ionic-liquid(PIL)monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI^(-)anion,which simultaneously inherits the lipophilicity of DOL,high ionic conductivity of imidazole,and excellent stability of PILs.Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate](TTMAP)was introduced to regulate the excessive Li^(+)-O coordination and prepare a flame-retardant SPE(DT-SPE)with prominent thermal stability,wide ESW,high ionic conductivity and abundant Lit transference numbers(t_(Li+)).As a result,the LiFePO_(4)|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g^(-1)at 0.2C and 30℃with a capacity retention rate of 98.68%after 500 cycles.This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability. 展开更多
关键词 Polymerized ionic liquid Solid polymer electrolyte Structural design Crosslinked 3d network Lithium metal battery
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Design,progress and challenges of 3D carbon-based thermally conductive networks
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作者 JING Yuan LIU Han-qing +2 位作者 ZHOU Feng DAI Fang-na WU Zhong-shuai 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期844-871,共28页
The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities a... The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities and many different structures,are regarded as key materials to improve the performance of electronic devices.We provide a critical overview of carbonbased 3D thermally conductive networks,emphasizing their preparation-structure-property relationships and their applications in different scenarios.A detailed discussion of the microscopic principles of thermal conductivity is provided,which is crucial for increasing it.This is followed by an in-depth account of the construction of 3D networks using different carbon materials,such as graphene,carbon foam,and carbon nanotubes.Techniques for the assembly of two-dimensional graphene into 3D networks and their effects on thermal conductivity are emphasized.Finally,the existing challenges and future prospects for 3D carbon-based thermally conductive networks are discussed. 展开更多
关键词 Carbon material 3d network GRAPHENE Thermal conductivity Heat transfer
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Estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy 被引量:1
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作者 Chuangbing Zhou Zuyang Ye +2 位作者 Chi Yao Xincheng Fan Feng Xiong 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期137-148,共12页
With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directi... With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different directions.Compared with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture networks.According to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip angle.As a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors. 展开更多
关键词 3d fracture network Geological entropy Directional entropic scale ANISOTROPY Hydraulic conductivity
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基于改进C3D模型的料仓视频分类识别方法
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作者 曹庆园 朱建鸿 《计算机测量与控制》 2025年第2期161-167,183,共8页
在自动上料控制系统中,针对传统电感式传感器容易受到外界复杂环境干扰,且需要进行繁琐校准工作等问题,提出了一种基于改进C3D模型的料仓视频视觉分类识别方法;基于实验需求,设计了合作标靶和建立了料仓识别视频数据集;将初始C3D模型作... 在自动上料控制系统中,针对传统电感式传感器容易受到外界复杂环境干扰,且需要进行繁琐校准工作等问题,提出了一种基于改进C3D模型的料仓视频视觉分类识别方法;基于实验需求,设计了合作标靶和建立了料仓识别视频数据集;将初始C3D模型作为主干网络进行改进,将该模型第3、4、5层卷积层进行精简,使得模型参数量大幅降低,有利于加快推理速度;在轻量化后的C3D模型上融合SE注意力机制,C3D模型从时空两个维度中提取特征,SE注意力机制可以有效在复杂场景视频帧中找出标靶显著区域,在兼顾时序信息的同时能够高效提取特征进而提高识别准确率;实验结果表明,SE-C3D识别模型准确率达到99.61%,与初始C3D模型相比,准确率提高2.48%,与其他典型三维卷积模型对比,各项性能指标也均有明显提升,对未来智能化上料系统的发展具有重要意义。 展开更多
关键词 上料系统 3d卷积神经网络 视频分类 SE注意力 模型轻量化
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Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model
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作者 Weiyan Liu 《Open Journal of Geology》 CAS 2024年第4期578-593,共16页
Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Ou... Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis. 展开更多
关键词 Deep Learning Convolutional Neural networks (CNN) Seismic Fault Identification U-Net 3d Model Geological Exploration
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Integration of CityGML and Oracle Spatial for implementing 3D network analysis solutionsand routing simulation within 3D-GIS environment 被引量:1
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作者 Umit ATILA Ismail Rakip KARAS Alias ABDUL-RAHMAN 《Geo-Spatial Information Science》 SCIE EI 2013年第4期221-237,共17页
3D navigation within a 3D-GIS environment is increasingly getting more popular and spreading to various fields.In thelast decade,especially after the 9/11 disaster,evacuating the complex and tall buildings of today in... 3D navigation within a 3D-GIS environment is increasingly getting more popular and spreading to various fields.In thelast decade,especially after the 9/11 disaster,evacuating the complex and tall buildings of today in case of emergencyhas been an important research area for scientists.Most of the current navigation systems are still in the 2D environmentand that is insufficient to visualize 3D objects and to obtain satisfactory solutions for the 3D environment.Therefore,there is currently still a lack of implementation of 3D network analysis and navigation for indoor spaces in respect toevacuation.The objective of this paper is to investigate and implement 3D visualization and navigation techniques andsolutions for indoor spaces within 3D-GIS.For realizing this,we have proposed a GIS implementation that is capable ofcarrying out 3D visualization of a building model stored in the CityGML format and perform analysis on a networkmodel stored in Oracle Spatial.The proposed GUI also provides routing simulation on the calculated shortest paths withvoice commands and visual instructions. 展开更多
关键词 3d-GIS 3d network analysis indoor navigation EVACUATION
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Novel Poly m eric Transition Metal Co m plexes Having1D Chain and 3D Networks Structures
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作者 洪茂椿 曹荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第5期384-392,共9页
The syntheses and structures of eleven novel polymeric transition metal complexes having one dimensional chain structures or three dimensional networks are summarized. They are prepared from the controlled assemblin... The syntheses and structures of eleven novel polymeric transition metal complexes having one dimensional chain structures or three dimensional networks are summarized. They are prepared from the controlled assembling reactions in organic solvents and characterized by X ray diffraction analyses. The spectroscopic or magnetic properties of some complexes are studied. 展开更多
关键词 polymeric metal complex linear chain structure 3d network
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基于3D注意力卷积与自监督学习的脑疾病分类方法
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作者 冀俊忠 于乐 雷名龙 《北京工业大学学报》 CAS CSCD 北大核心 2024年第3期307-315,共9页
为了提升现有脑疾病分类方法提取三维空间特征的能力,提出一种融合3D注意力卷积与自监督学习的分类模型。首先,提出一种基于残差结构的3D注意力卷积神经网络来提取空间特征,利用3D注意力机制区分体素数据中不同空间位置的重要性;其次,... 为了提升现有脑疾病分类方法提取三维空间特征的能力,提出一种融合3D注意力卷积与自监督学习的分类模型。首先,提出一种基于残差结构的3D注意力卷积神经网络来提取空间特征,利用3D注意力机制区分体素数据中不同空间位置的重要性;其次,利用空间特征构建一个基于自监督学习的多任务学习框架,通过基于空间连续性的自监督辅助任务来进一步挖掘体素的空间依赖关系;最后,通过辅助任务与目标分类任务的联合训练优化神经网络参数,进而提升分类模型的性能。在ABIDE-Ⅰ和ABIDE-Ⅱ数据集上的实验结果表明,所提方法具有优异的分类性能,分类结果也具备良好的可解释性。 展开更多
关键词 脑疾病分类 体素数据 空间特征 三维卷积神经网络 自监督学习 注意力机制
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Quantification of 3D macropore networks in forest soils in Touzhai valley(Yunnan,China)using X-ray computed tomography and image analysis 被引量:2
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作者 ZHANG Jia-ming XU Ze-min +2 位作者 LI Feng HOU Ru-ji REN Zhe 《Journal of Mountain Science》 SCIE CSCD 2017年第3期474-491,共18页
The three dimensional (3D) geometry of soil macropores largely controls preferential flow, which is a significant infiltrating mechanism for rainfall in forest soils and affects slope stability. However, detailed st... The three dimensional (3D) geometry of soil macropores largely controls preferential flow, which is a significant infiltrating mechanism for rainfall in forest soils and affects slope stability. However, detailed studies on the 3D geometry of macropore networks in forest soils are rare. The intense rainfall-triggered potentially unstable slopes were threatening the villages at the downstream of Touzhai valley (Yunnan, China). We visualized and quantified the 3D macropore networks in undisturbed soil columns (Histosols) taken from a forest hillslope in Touzhai valley, and compared them with those in agricultural soils (corn and soybean in USA; barley, fodder beet and red fescue in Denmark) and grassland soils in USA. We took two large undisturbed soil columns (250 mm^25o mmxsoo mm), and scanned the soil columns at in-situ soil water content conditions using X-ray computed tomography at a voxel resolution of 0.945 × 0.945 × 1.500o mm^3. After reconstruction and visualization, we quantified the characteristics of macropore networks. In the studied forest soils, the main types of maeropores were root channels, inter-aggregate voids, maeropores without knowing origin, root-soil interfaee and stone-soil interface. While maeropore networks tend to be more eomplex, larger, deeper and longer. The forest soils have high maeroporosity, total maeropore wall area density, node density, and large maeropore volume, hydraulie radius, mean maeropore length, angle, and low tortuosity. The findings suggest that maeropore networks in the forest soils have high inter- connectivity, vertical continuity, linearity and less vertically oriented. 展开更多
关键词 Slope stability Touzhai valley Rainfall infiltration Forest soils X-ray computed tomography 3d macropore networks
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Ex vivo 3D osteocyte network construction with primary murine bone cells 被引量:2
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作者 Qiaoling Sun Yexin Gu +3 位作者 Wenting Zhang Leah Dziopa Jenny Zilberberg Woo Lee 《Bone Research》 SCIE CAS CSCD 2015年第3期152-163,共12页
Osteocytes reside as three-dimensionally(3D) networked cells in the lacunocanalicular structure of bones and regulate bone and mineral homeostasis. Despite of their important regulatory roles, in vitro studies of os... Osteocytes reside as three-dimensionally(3D) networked cells in the lacunocanalicular structure of bones and regulate bone and mineral homeostasis. Despite of their important regulatory roles, in vitro studies of osteocytes have been challenging because:(1) current cell lines do not sufficiently represent the phenotypic features of mature osteocytes and(2) primary cells rapidly differentiate to osteoblasts upon isolation. In this study, we used a 3D perfusion culture approach to:(1) construct the 3D cellular network of primary murine osteocytes by biomimetic assembly with microbeads and(2) reproduce ex vivo the phenotype of primary murine osteocytes, for the first time to our best knowledge. In order to enable 3D construction with a sufficient number of viable cells, we used a proliferated osteoblastic population of healthy cells outgrown from digested bone chips. The diameter of microbeads was controlled to:(1) distribute and entrap cells within the interstitial spaces between the microbeads and(2) maintain average cell-to-cell distance to be about 19 mm. The entrapped cells formed a 3D cellular network by extending and connecting their processes through openings between the microbeads. Also, with increasing culture time, the entrapped cells exhibited the characteristic gene expressions(SOST and FGF23) and nonproliferative behavior of mature osteocytes. In contrast, 2D-cultured cells continued their osteoblastic differentiation and proliferation. This 3D biomimetic approach is expected to provide a new means of:(1) studying flow-induced shear stress on the mechanotransduction function of primary osteocytes,(2) studying physiological functions of 3D-networked osteocytes with in vitro convenience,and(3) developing clinically relevant human bone disease models. 展开更多
关键词 CELL FIGURE Ex vivo 3d osteocyte network construction with primary murine bone cells BONE
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Biomass-Derived Nitrogen and Sulfur Co-Doped 3D Carbon Networks with Interconnected Meso-Microporous Structure for High-Performance Supercapacitors 被引量:1
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作者 Zhu Jiajia Hao Xiaodong +3 位作者 Wang Jie Guo Hongshuai Dou Hui Zhang Xiaogang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第4期590-602,共13页
Three-dimensional(3D)carbon networks have been explored as promising capacitive materials thanks to their unique structural features such as large ion-accessible surface area and interconnected porous networks,thus en... Three-dimensional(3D)carbon networks have been explored as promising capacitive materials thanks to their unique structural features such as large ion-accessible surface area and interconnected porous networks,thus enhancing both ions and electrons transport.Here,sustainable bacterial cellulose(BC)is used both precursor and template for facile synthesis of free-standing N,S-codoped 3Dcarbon networks(a-NSC)by the pyrolysis and activation of polyrhodanine coated BC.The synthesized a-NSC shows highly conductive interconnected porous networks(24S·cm^(-1)),large surface area(1 420m^2·g^(-1))with hierarchical meso-microporosity,and high-level heteroatoms codoping(N:3.1%in atom,S:3.2%in atom).Benefitting from these,a-NSC as binder-free electrode exhibits an ultrahigh specific capacitance of 340F·g^(-1)(24μF·cm^(-2))at the current density of 0.5A·g^(-1)in 6MKOH electrolyte,high-rate capability(71%at 20A·g^(-1))and excellent cycle stability.Furthermore,the assembled symmetrical supercapacitor displays a much short time constant of 0.35sin 1MTEABF4/AN electrolyte,obtaining a maximum energy density of 32.1W·h·kg^(-1 )at power density of 637W·kg^(-1).The in situ multi-heteroatoms doping enables biocellulose-derived carbon networks to exploit its full potentials in energy storage applications,which can be extended to other dimensional carbon nanostructures. 展开更多
关键词 bacterial cellulose 3d carbon networks FREE-STANDING N S-codoping SUPERCAPACITORS
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基于流水线计算的3D NoC测试规划研究
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作者 胡聪 白杨 +2 位作者 周甜 朱爱军 许川佩 《计算机应用与软件》 北大核心 2024年第5期240-246,303,共8页
为了提高三维片上网络(3D NoC)资源内核的测试效率,提出一种在功耗约束条件下多播流水线并行测试同构核与单播测试异构核相结合的方法对IP核进行测试。为了减少测试数据因资源冲突而进行等待的时间,设计一种改进XYZ路由算法,并采用改进... 为了提高三维片上网络(3D NoC)资源内核的测试效率,提出一种在功耗约束条件下多播流水线并行测试同构核与单播测试异构核相结合的方法对IP核进行测试。为了减少测试数据因资源冲突而进行等待的时间,设计一种改进XYZ路由算法,并采用改进人工蜂群(ABC)算法求解最佳测试规划方案。以国际标准电路测试集ITC'02作为实验对象,结果表明,测试时间最大优化率达到15.45%,与其他测试规划方法相比该文方法能有效地提高并行测试效率。 展开更多
关键词 三维片上网络 流水线计算 多播通信 测试规划 人工蜂群算法
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基于3D卷积神经网络的膏体屈服应力预测 被引量:1
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作者 刘泽民 程海勇 +5 位作者 毛明发 李在利 吴顺川 姜关照 孙伟 刘伟铧 《工程科学学报》 EI CSCD 北大核心 2024年第8期1337-1348,共12页
膏体流变性能是膏体充填技术重要指标,是金属矿膏体充填工艺流程的重要工程参数.本文提出一种基于3D卷积神经网络的膏体屈服应力预测方法,通过制定图像采集标准并研发图像采集装置采集图像数据集.经Sobel算子实现膏体边缘检测、全图缩... 膏体流变性能是膏体充填技术重要指标,是金属矿膏体充填工艺流程的重要工程参数.本文提出一种基于3D卷积神经网络的膏体屈服应力预测方法,通过制定图像采集标准并研发图像采集装置采集图像数据集.经Sobel算子实现膏体边缘检测、全图缩小等预处理,得到膏体图像数据集.采用十折交叉验证方法划分数据集,避免因单次随机划分造成的偶然误差.以膏体图像–屈服应力数据集为基础,利用3D卷积神经网络模型提取膏体纹理特征和时序信息等,又通过引入直方图均衡化算法的图像增强策略减少环境因素干扰,提高模型稳健性.利用预处理后的数据集在3D卷积神经网络模型上做训练和测试,得到模型损失值曲线图和混淆矩阵.将屈服应力模型预测结果进行分析,又引入卷积注意力机制嵌入到卷积神经网络实现模型优化,并对模型参数进行调整,模型预测平均准确率从93.26%提升至98.19%,论证了基于3D卷积神经网络的膏体屈服应力预测方法可行性.经图像增强处理的数据集应用到各模型中,模型预测平均准确率均提升3%以上.相比传统膏体流变测量方式,解决了传统膏体屈服应力测量操作复杂、外部因素扰动大、工程现场难以开展等问题. 展开更多
关键词 膏体充填 流变性能 3d卷积神经网络 屈服应力 预测
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Networked 3D Virtual Museum System 被引量:5
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作者 Yong-MooKwon Ig-JaeKim 《系统仿真学报》 CAS CSCD 2003年第3期301-305,共5页
Virtual heritage has become increasingly important in the conservation, preservation, and interpretation of our cultural and natural history. Moreover, rapid advances in digital technologies in recent years offer virt... Virtual heritage has become increasingly important in the conservation, preservation, and interpretation of our cultural and natural history. Moreover, rapid advances in digital technologies in recent years offer virtual heritage new direction. This paper introduces our approach toward a networked 3D virtual museum system, especially, how to model, manage, present virtual heritages and furthermore how to use computer network for the share of virtual heritage in the networked virtual environment. This paper first addresses a 3D acquisition and processing technique for virtual heritage modeling and shows some illustrative examples. Then, this paper describes a management of virtual heritage assets that are composed by various rich media. This paper introduces our schemes to present the virtual heritages, which include 3D virtual heritage browser system, CAVE system, and immersive VR theater. Finally, this paper presents the new direction of networked 3D virtual museum of which main idea is remote guide of the virtual heritage using the mixed reality technique. 展开更多
关键词 CAVE 虚拟现实 虚拟继承 网络化三维虚拟博物馆 VR剧场
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基于3D U-Net++卷积神经网络的断层识别方法及应用 被引量:1
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作者 李卿武 王兴建 +4 位作者 张永恒 文雪梅 陈阳 王崇名 廖万平 《物探化探计算技术》 CAS 2024年第3期284-291,共8页
断层解释是地震资料解释的基础与关键,准确合理的断层识别对油气开采有着至关重要的作用。随着油田对断层解释精度需求的日益提高,单纯通过基于人工的如相干体、曲率等属性的传统断层解释方法,其精度已无法满足要求。笔者在U-Net卷积神... 断层解释是地震资料解释的基础与关键,准确合理的断层识别对油气开采有着至关重要的作用。随着油田对断层解释精度需求的日益提高,单纯通过基于人工的如相干体、曲率等属性的传统断层解释方法,其精度已无法满足要求。笔者在U-Net卷积神经网络模型的基础上进行改进,得出了一种自动断层识别方法,能够从任意三维地震图像中自动提取断层。文中该模型在足量样本集训练下,对两区块的实际地震数据进行自动断层识别,将识别结果进行分析对比。实验结果表明,该模型能够对任意三维地震数据进行自动断层识别,基于3D U-Net++网络模型的断层识别结果相比于传统U-Net网络识别结果准确性有明显提高,对潜山内部的小断层识别也表现出良好的效果,明显提高了常规、复杂断层识别的工作效率。 展开更多
关键词 断层识别 三维地震数据 卷积神经网络 3d U-Net++
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基于深度学习的自动驾驶场景3D目标检测方法
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作者 张学锋 唐永吉 +3 位作者 杨武洲 樊旭 黄永鹤 谢悦 《苏州科技大学学报(自然科学版)》 CAS 2024年第2期63-70,共8页
针对传统PV-RCNN在点云上采样效率低下和采样精度存在偏差等问题,提出了一种基于PV-RCNN改进的3D目标检测方法。更改关键点采样策略,使得有限的关键点可以更加地聚集在proposal区域范围内,更多的编码有效前景点特征来用于后面的proposal... 针对传统PV-RCNN在点云上采样效率低下和采样精度存在偏差等问题,提出了一种基于PV-RCNN改进的3D目标检测方法。更改关键点采样策略,使得有限的关键点可以更加地聚集在proposal区域范围内,更多的编码有效前景点特征来用于后面的proposal refinement,有效产生更具有代表性的关键点。用局部特征聚合的VectorPool聚合模块取代体素集抽象和ROI网格池化模块中的集合抽象,更高效的针对稀疏和不规则点云数据进行编码。在KITTI数据集上对算法验证,结果表明:行人鸟瞰图检测,困难级别检测精度提升较为显著,达到了10.46%,整体帧率提升为33.74%,文中的方法拥有更好的检测性能。 展开更多
关键词 3d目标检测 卷积神经网络 点云 SPC关键点采样 VectorPool聚合模块
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Metal–Oleate Complex?Derived Bimetallic Oxides Nanoparticles Encapsulated in 3D Graphene Networks as Anodes for Efficient Lithium Storage with Pseudocapacitance 被引量:1
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作者 Yingying Cao Kaiming Geng +6 位作者 Hongbo Geng Huixiang Ang Jie Pei Yayuan Liu Xueqin Cao Junwei Zheng Hongwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第1期250-263,共14页
In this manuscript, we have demonstrated the delicate design and synthesis of bimetallic oxides nanoparticles derived from metal–oleate complex embedded in 3D graphene networks(MnO/CoMn_2O_4  GN), as an anode mater... In this manuscript, we have demonstrated the delicate design and synthesis of bimetallic oxides nanoparticles derived from metal–oleate complex embedded in 3D graphene networks(MnO/CoMn_2O_4  GN), as an anode material for lithium ion batteries. The novel synthesis of the MnO/CoMn_2O_4  GN consists of thermal decomposition of metal–oleate complex containing cobalt and manganese metals and oleate ligand, forming bimetallic oxides nanoparticles, followed by a selfassembly route with reduced graphene oxides. The MnO/CoMn_2O_4  GN composite, with a unique architecture of bimetallic oxides nanoparticles encapsulated in 3D graphene networks, rationally integrates several benefits including shortening the di usion path of Li^+ ions, improving electrical conductivity and mitigating volume variation during cycling. Studies show that the electrochemical reaction processes of MnO/Co Mn_2O_4  GN electrodes are dominated by the pseudocapacitive behavior, leading to fast Li^+ charge/discharge reactions. As a result, the MnO/CoMn_2O_4  GN manifests high initial specific capacity, stable cycling performance, and excellent rate capability. 展开更多
关键词 Metal–oleate complex Bimetallic oxides NANOPARTICLES Porous architecture 3d GRAPHENE networkS Lithium ion batteries
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Static dissolution-induced 3D pore network modification and its impact on critical pore attributes of carbonate rocks 被引量:2
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作者 ANDRIAMIHAJA Spariharijaona PADMANABHAN Eswaran +1 位作者 BEN-AWUAH Joel SOKKALINGAM Rajalingam 《Petroleum Exploration and Development》 2019年第2期374-383,共10页
To determine the effect of dissolution on pore network development in carbonate rocks, dissolution experiments, X-Ray microtomography, and thin section analysis were conducted on argillaceous limestone and grain limes... To determine the effect of dissolution on pore network development in carbonate rocks, dissolution experiments, X-Ray microtomography, and thin section analysis were conducted on argillaceous limestone and grain limestone samples at different temperatures and constant pH, HCl concentration. The relationship between Ca^(2+) concentration and time was revealed through the experiments; pore size distribution before and after dissolution indicate that there is no correlation between the temperature and pore size variation, but pore size variation in grain limestone is more significant, indicating that the variation is mainly controlled by the heterogeneity of the rock itself(initial porosity and permeability) and the abundance of unstable minerals(related to crystal shape, size and mineral type). At different temperatures, the two kinds of carbonate rocks had very small variation in pore throat radius from 0.003 mm to 0.040 mm, which is 1.3 to 3.5 times more, 1.7 on average of the original pore throat radius. Their pore throat length varied from 0.05 mm to 0.35 mm. The minor changes in the pore throat radius, length and connectivity brought big changes to permeability of up to 1 000×10^(-3) μm^2. 展开更多
关键词 3d PORE networks CARBONATE ROCKS PORE structure MUDSTONE grainstone ACIDIZING dissolution X-Ray micro tomography
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A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding
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作者 YANG E WANG Xiao-Qin QIN Ye-Yan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1365-1368,共4页
The title complex, {[Cu2(4,4'-bipyridine)2(μ-O2CMe)2(O2CMe)2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474... The title complex, {[Cu2(4,4'-bipyridine)2(μ-O2CMe)2(O2CMe)2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474(5), b = 11.7566(2), c = 19.5380(6)A, β = 92.930(2)°, V = 3084.84(16) A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F(000) = 1424 and μ(MoKα) = 1.436 mm^-1. With the use of 2062 observed reflections (I 〉 2σ(I)), the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network. 展开更多
关键词 molecular ladder dimeric copper acetate 3d supramolecular network
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