检索结果-南通市图书馆

Perception Enhanced Deep Deterministic Policy Gradient for Autonomous Driving in Complex Scenarios

Computer modeling in Engineering & Sciences 2024年第7期140卷 557-576页

作者： Lyuchao Liao Hankun Xiao Pengqi Xing Zhenhua Gan Youpeng He Jiajun Wang Fujian provincial key laboratory of Automotive Electronics and Electric Drive Fujian University of TechnologyFuzhou350118China Fujian provincial Universities Engineering Research Center for Intelligent Driving technology Fuzhou350118China

Autonomous driving has witnessed rapid advancement;however,ensuring safe and efficient driving in intricate scenarios remains a critical *** particular,traffic roundabouts bring a set of challenges to autonomous driving due to the unpredictable entry and exit of vehicles,susceptibility to traffic flow bottlenecks,and imperfect data in perceiving environmental information,rendering them a vital issue in the practical application of autonomous *** address the traffic challenges,this work focused on complex roundabouts with multi-lane and proposed a Perception EnhancedDeepDeterministic Policy Gradient(PE-DDPG)for AutonomousDriving in the ***,themodel incorporates an enhanced variational autoencoder featuring an integrated spatial attention mechanism alongside the Deep Deterministic Policy Gradient framework,enhancing the vehicle’s capability to comprehend complex roundabout environments and make ***,the PE-DDPG model combines a dynamic path optimization strategy for roundabout scenarios,effectively mitigating traffic bottlenecks and augmenting throughput *** experiments were conducted with the collaborative simulation platform of CARLA and SUMO,and the experimental results show that the proposed PE-DDPG outperforms the baseline methods in terms of the convergence capacity of the training process,the smoothness of driving and the traffic efficiency with diverse traffic flow patterns and penetration rates of autonomous vehicles(AVs).Generally,the proposed PE-DDPGmodel could be employed for autonomous driving in complex scenarios with imperfect data.

关键词： Autonomous driving traffic roundabouts deep deterministic policy gradient spatial attention mechanisms

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Development and application of a Power Law Constitutive model for Eddy Current Dampers

引用

Computer modeling in Engineering & Sciences 2024年第3期138卷 2403-2419页

作者： Longteng Liang Zhouquan Feng Hongyi Zhang Zhengqing Chen Changzhao Qian School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen361024China Hunan provincial key laboratory ofWind and Bridge Engineering Hunan UniversityChangsha410082China Fujian provincial key laboratory ofWind Disaster and Engineering Xiamen University of TechnologyXiamen361024China State key laboratory of Bridge Engineering Safety and Resilience Hunan UniversityChangsha410082China

Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.

关键词： Eddy current damper constitutive model finite element analysis vibration control power law constitutive model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow

引用

High Voltage 2024年第1期9卷 127-136页

作者： Shixin Zhao Xingbao Lyu Aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev Aleksandr Chirtsov Gennadii Shabanov Zhongxiang Zhou School of Physics Harbin Institute of TechnologyHarbinChina Physics Department Saint Petersburg Electrotechnical University“LETI”St.PetersburgRussia Heilongjiang provincial key laboratory of Plasma Physics and application technology HarbinChina Physics Department St.Petersburg State UniversitySt.PetersburgRussia Konstantinov Petersburg Nuclear Physics Institute National Research Centre“Kurchatov Institute”GatchinaRussia

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball ***,crucial aspects concerning the plasma components of the resulting afterglow remain ***,the measurement of the electron density,a critical parameter,has not been fully achieved thus *** this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and *** antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived *** findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive *** the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two *** measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles.

关键词： holds luminous electrolytic

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

shinyTempSignal:an R shiny application for exploring temporal and other phylogenetic signals

引用

Journal of Genetics and Genomics 2024年第7期51卷 762-768页

作者： Li Zhan Xiao Luo Wenqin Xie Xuan-An Zhu Zijing Xie Jianfeng Lin Lin Li Wenli Tang Rui Wang Lin Deng Yufan Liao Bingdong Liu Yantong Cai Qianwen Wang Shuangbin Xu Guangchuang Yu Department of Bioinformatics School of Basic Medical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China Faculty of Computers Guangdong University of TechnologyGuangzhouGuangdong 510006China Ubigene Biosciences Co. Ltd.GuangzhouGuangdong 510530China State key laboratory of Applied Microbiology Southern China Guangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationGuangdong Open Laboratory of Applied MicrobiologyGuangdong Institute of MicrobiologyGuangdong Academy of SciencesGuangzhouGuangdong 510070China

The molecular clock model is fundamental for inferring species divergence times from molecular ***,its direct application may introduce significant biases due to sequencing errors,recombination events,and inaccurately labeled sampling *** accuracy necessitates rigorous quality control measures to identify and remove potentially erroneous ***,while not all branches of a phylogenetic tree may exhibit a clear temporal signal,specific branches may still adhere to the assumptions,with varying evolutionary *** a relaxed molecular clock model better aligns with the complexities of *** root-to-tip regression method has been widely used to analyze the temporal signal in phylogenetic studies and can be generalized for detecting other phylogenetic *** its utility,there remains a lack of corresponding software implementations for broader *** address this gap,we present shinyTempSignal,an interactive web application implemented with the shiny framework,available as an R package and publicly accessible at https://***/YuLab-SMU/*** tool facilitates the analysis of temporal and other phylogenetic signals under both strict and relaxed *** extending the root-to-tip regression method to diverse signals,shinyTempSignal helps in the detection of evolving features or traits,thereby laying the foundation for deeper insights and subsequent analyses.

关键词： Molecular clock Root-to-tip regression Temporal signal Phylogenetic signal

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Influence of the penetration of adjacent X-section cast-in-place concrete(XCC)pile on the existing XCC pile in sand

引用

Journal of zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 557-572页

作者： Peng ZHOU Jianhui XU Changjie XU Guangwei CAO Jie CUP Xuanming DING School of Civil Engineering and Architecture State Key Laboratory of Performance Monitoring and Protecting of Rail Transit InfrastructureEast China Jiaotong UniversityNanchang330013China Guangdong key laboratory of Earthquake Engineering and application technology Earthquake Engineering Research&Test CenterGuangzhou UniversityGuangzhou510006China key laboratory of New technology for the Construction of Cities in Mountain Areas College of Civil EngineeringChongqing UniversityChongqing400045China Zijin School of Geology and Mining Fuzhou UniversityFuzhou350116China

A series of small-scale 1g X-section cast-in-place concrete(XCC)pile-penetration model tests were conducted to study the effects of soil density and pile geometry on the lateral responses of an existing pile and the variations in surrounding soil *** results showed that the bending patterns of existing XCC piles varied with penetration *** lateral response of the existing pile was sensitive to the change in relative density and pile *** example,the bending moment of the existing pile increased along with these *** development of the radial stressσ′r/σ′v0 of the soil around an existing pile showed different trends at various depths during the penetration of the adjacent ***,the change in radial stress during the penetration of the XCC pile did not exhibit the“h/R effect”that was observed in the free-field soil,due to the shielding effect of the existing *** peak value of radial stressσ′r_max/σ′v0 decreased exponentially as the radial distance r/R *** attenuation ofσ′r_max/σ′v0 with r/R in the loose sand was faster than in the medium-dense or dense ***σ′r_max/σ′v0 at the same soil location increased with the cross-section geometry parameter.

关键词： X-section cast-in-place concrete(XCC)pile Test Penetration Sand Lateral response Radial stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spontaneous grain refinement effect of rare earth zinc alloy anodes enables stable zinc batteries

引用

National Science Review 2024年第7期11卷 252-262页

作者： Manjing Chen Yuxiang Gong Yunxiang Zhao Yexin Song Yan Tang Zhiyuan Zeng Shuquan Liang Peng Zhou Bingan Lu Xiaotan Zhang Jiang Zhou School of Materials Science&Engineering Hunan Provincial Key Laboratory of Electronic Packaging and Advanced Functional MaterialsCentral South University Institute of Materials Research Tsinghua Shenzhen International Graduate School Tsinghua University Department of Materials Science and Engineering City University of Hong Kong Hunan provincial key Defense laboratory of High Temperature Wear-Resisting Materials and Preparation technology Hunan University of Science and Technology School of Physics and Electronics Hunan University School of Chemistry and Materials Science University of Science and Technology of China Suzhou Institute for Advanced Research University of Science and Technology of China

Irreversible interfacial reactions at the anodes pose a significant challenge to the long-term stability and lifespan of zinc（Zn） metal batteries, impeding their practical application as energy storage devices. The plating and stripping behavior of Zn ions on polycrystalline surfaces is inherently influenced by the microscopic structure of Zn anodes, a comprehensive understanding of which is crucial but often overlooked. Herein, commercial Zn foils were remodeled through the incorporation of cerium（Ce）elements via the ‘pinning effect’ during the electrodeposition process. By leveraging the electron-donating effect of Ce atoms segregated at grain boundaries（GBs）, the electronic configuration of Zn is restructured to increase active sites for Zn nucleation. This facilitates continuous nucleation throughout the growth stage,leading to a high-rate instantaneous-progressive composite nucleation model that achieves a spatially uniform distribution of Zn nuclei and induces spontaneous grain refinement. Moreover, the incorporation of Ce elements elevates the site energy of GBs, mitigating detrimental parasitic reactions by enhancing the GB stability. Consequently, the remodeled ZnCe electrode exhibits highly reversible Zn plating/stripping with an accumulated capacity of up to 4.0 Ah cm-2in a Zn symmetric cell over 4000 h without short-circuit behavior. Notably, a ～0.4 Ah Zn||NH4V4O10pouch cell runs over 110 cycles with 83% capacity retention with the high-areal-loading cathode(≈20 mg cm-2). This refining-grains strategy offers new insights into designing dendrite-free metal anodes in rechargeable batteries.

关键词： grain refinement rare earth GB stability zinc metal batteries

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Bioinspired Scraper-File Type Frequency-Doubling Ultrasonic Exciter

引用

Journal of Bionic Engineering 2024年第4期21卷 1801-1816页

作者： Wenshuai Wu Mingshuo Zhang Zeming Li Guang Yao Xinggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing100191China Institute of Bionic and Micro-Nano Systems Beihang UniversityBeijing100191China Guangdong provincial key laboratory of Minimally Invasive Surgical Instruments and Manufacturing technology Guangdong University of TechnologyGuangzhou510006China

In the natural world,leaf-cutting ants cause vibrations through their mutual scraping of file-scraper *** this study,we designed a Biomimetic Ultrasonic Exciter(BUE)that imitates leaf-cutting *** operating characteristics of the BUE were studied through experimental testing and finite element *** results showed that the BUE could generate stable ultrasonic vibrations,and that the excitation frequency only needed to be half the Output Frequency(OF).This frequency-doubling phenomenon was conducive to achieving BUE *** further explore the phenomenon of frequency-doubling vibration output,this study designed scrapers of five different sizes,conducted excitation and first-order natural frequency measurement tests,and the corresponding finite element *** was found that each scraper could operate in frequency-doubling mode,but the operating frequency and natural mode frequencies did not correspond with one *** further explicate experimental and simulation results,a two-degrees-of-freedom vibration model was *** was evident that the contact relationship between the dentate disc and scraper introduced strong nonlinear factors into the system,accounting for the frequency-doubling phenomenon and the difference between the BUE’s operating and mode *** BUE could be expected to facilitate the production of high-power micro-ultrasonic generators and has potential application value in the fields of mechanical processing,industrial production,and medical health.

关键词： Leaf-cutting ants Power ultrasound Nonlinear vibration Ultrasonic scalpel Micro vibrator

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research on the variation of dielectric properties of oil-paper insulation for power equipment over a wide temperature range

引用

High Voltage 2024年第3期9卷 648-658页

作者： Mingze Zhang Muhe Yu Wen Zhou Yilin Liang Shengjie Lei Yunbo Shi Limin Qu key laboratory of Engineering Dielectrics and Its application Ministry of Education Harbin University of Science and TechnologyHarbinChina School of Measurement and Communication Engineering Harbin University of Science and TechnologyHarbinChina Electric Power Research Institute State Grid Heilongjiang Electric Power Company LimitedHarbinChina

The main part of oil-immersed power equipment is oil-paper *** lower ambient temperatures,transformer oil will become *** a result,compared to those at room temperature or operating temperature,the frequency domain dielectric properties of oil-paper insulation at low temperatures are drastically *** evaluating the insulation condition of electrical equipment,it is essential to accurately determine their dielectric *** paper described the FDS test,the DC conductivity test,and the transformer oil viscosity test,which was carried out in a laboratory environment for different ageing of oil-immersed pressboard and transformer oil at 233–373 *** ef-fects of temperature on the dielectric properties at the competing mechanisms of polarisation and conductivity loss were clarified based on variations of the FDS *** the viscosity change of ageing transformer oil at low temperatures,the Arrhenius and VFT viscosity equations were used to achieve a fitting calculation in the different temperature *** on the molecular/ion transition model in the force field and electric field,the characterisation relationships between the dynamic viscosity,DC conductivity,and test temperature of transformer oil were *** limita-tions of conventional transformer oil equivalent dielectric relaxation models over a wide temperature range were finally clarified by combining the test findings of the DC con-ductivity over a wide temperature range with observed and simulated *** paper provides an essential theoretical reference when using the FDS test to diagnose the insulation performance of oil-immersed power equipment in extremely cold regions.

关键词： insulation viscosity immersed

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Design and experimental research on the sweet potato seedling transplanting mechanism of the planetary gear train with deformed elliptical gear transmission

引用

International Journal of Agricultural and Biological Engineering 2024年第3期17卷 91-99页

作者： Bingliang Ye Yuxuan Ye Haili Zhou Gaohong Yu Xiong Zhao Bin Deng Faculty of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China zhejiang Province key laboratory of Transplanting Equipment and technology Hangzhou 310018China key laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsHangzhou 310018China

Aiming at the lack of suitable machines for sweet potato seedling transplanting in China,and according to the agronomic requirements for the horizontal insertion method of sweet potato seedling,a new sweet potato seedling transplanting mechanism of planetary gear train was proposed based on the non-uniform transmission of deformed elliptical *** working principle of the transplanting mechanism was analyzed,and the kinematics modeling and analysis of the mechanism were carried *** study established the numerical objectives of the transplanting mechanism and applied the theory of membership function to establish a mathematical model for the parameter-guided optimization design of the transplanting *** parameter-guided optimization design software was developed to obtain a set of optimal mechanism parameters that satisfied the motion trajectory of sweet potato transplanting and the posture of the transplanting *** on the optimized parameters,the structure of the transplanting mechanism was designed,and a virtual prototype of the mechanism was created,whereby a virtual motion simulation of the transplanting mechanism was conducted to verify the correctness of the kinematics model and design of the *** high-speed photographic kinematics test of the mechanism prototype and sweet potato seedling transplanting tests were conducted to test the mechanism’s kinematic characteristics and transplanting *** test results show that the test trajectory of the mechanism and test posture of the transplanting arm are almost consistent with the theoretical and simulation trajectory,meeting the agronomic requirements of the horizontal insertion method of sweet potato seedling;And when the rotary speed of the mechanism are 20 r/min and 30 r/min,the average success ratios of sweet potato seedlings transplanting are 90%and 82%,respectively,which prove the application feasibility of the mechanism in the practical machines.

关键词： sweet potato seedling transplanter transplanting mechanism deformed elliptical gear transmission kinematics analysis membership function optimization design

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intelligent diagnostic model for pterygium by combining attention mechanism and MobileNetV2

引用

International Journal of Ophthalmology(English edition) 2024年第7期17卷 1184-1192页

作者： Mao-Nian Wu Kai He Yi-Bei Yu Bo Zheng Shao-Jun Zhu Xiang-Qian Hong Wen-Qun Xi Zhe Zhang School of Information Engineering Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina zhejiang Province key laboratory of Smart Management and application of Modern Agricultural Resources Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina School of Mathematical Information Shaoxing UniversityShaoxing 312000Zhejiang ProvinceChina Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen 518040Guangdong ProvinceChina

AIM:To evaluate the application of an intelligent diagnostic model for ***:For intelligent diagnosis of pterygium,the attention mechanisms—SENet,ECANet,CBAM,and Self-Attention—were fused with the lightweight MobileNetV2 model structure to construct a tri-classification *** study used 1220 images of three types of anterior ocular segments of the pterygium provided by the Eye Hospital of Nanjing Medical *** classification models—VGG16,ResNet50,MobileNetV2,and EfficientNetB7—were trained on the same dataset for *** evaluate model performance in terms of accuracy,Kappa value,test time,sensitivity,specificity,the area under curve(AUC),and visual heat map,470 test images of the anterior segment of the pterygium were ***:The accuracy of the MobileNetV2+Self-Attention model with 281 MB in model size was 92.77%,and the Kappa value of the model was 88.92%.The testing time using the model was 9ms/image in the server and 138ms/image in the local *** sensitivity,specificity,and AUC for the diagnosis of pterygium using normal anterior segment images were 99.47%,100%,and 100%,respectively;using anterior segment images in the observation period were 88.30%,95.32%,and 96.70%,respectively;and using the anterior segment images in the surgery period were 88.18%,94.44%,and 97.30%,***:The developed model is lightweight and can be used not only for detection but also for assessing the severity of pterygium.

关键词： deep learning attention mechanism pterygium intelligent diagnosis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：