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智能车辆横向控制研究

机器人 2003年第1期25卷 26-30页

作者：周俊姬长英南京农业大学工学院南京210031

本文分析了智能车辆横向控制特性 ,说明了目前一些研究中的不足 ,并探讨了模糊控制方法 .仿真结果表明 ,该算法对纵向速度。

关键词：智能车辆横向控制模糊控制智能交通系统

基于混沌序列的MIMO-OFDM雷达通信一体化波形设计

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应用科技 2024年第3期51卷 121-127页

作者：赵忠凯闫秋贞哈尔滨工程大学信息与通信工程学院黑龙江哈尔滨150001

为了解决多输入多输出的正交频分复用(multiple input multiple output orthogonal frequency division multiplexing,MIMO-OFDM)雷达通信一体化信号波形由于通信信息的不确定性导致模糊函数旁瓣水平较高以及系统雷达探测能力较差的问题... 详细信息

为了解决多输入多输出的正交频分复用(multiple input multiple output orthogonal frequency division multiplexing,MIMO-OFDM)雷达通信一体化信号波形由于通信信息的不确定性导致模糊函数旁瓣水平较高以及系统雷达探测能力较差的问题,提出利用混沌序列对通信信息进行直接扩频。但普通单级混沌序列具有保密性低,可用数量少,容易被破解的缺点。因此采用一种基于加权算法优化的混合型级联混沌序列对通信信息进行扩频调制,然后再通过MIMO-OFDM一体化系统进行传输。由仿真结果可知,加权后的级联混沌序列相关性和误码率性能较m序列和Gold序列更好,经此序列扩频后的一体化信号模糊函数旁瓣水平会更低,故该一体化波形雷达探测性能更佳。且混沌序列越长,信号波形雷达探测能力越好。

关键词：达通信一体化级联混沌序列模糊函数非周期相关性扩频 MIMO-OFDM 加权算法

Intelligent manufacture adapts to agile manufacture production mode in the 21st century

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Hunan Agricultural Science ＆ Technology Newsletter 2003年第3期4卷 19-22页

作者： Li Xurong Department of engineering and Technology, Huazhong agriculture university, Wuhan 430070, China Department of engineering and Technology Huazhong Agriculture University Wuhan 430070 China

The paper describes the characteristics of the intelligent manufacturing system and production mode in the 21st century in the information age, therefore draws a conclusion that the intelligent manufacturing system ad... 详细信息

关键词： intelligent manufacture agile manufacture production mode

结合空间语义注意力的二段式遥感图像修复网络

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自然资源遥感 2024年第1期36卷 58-66页

作者：刘宇佳谢诗哲杜阳严瑾南燕云温中凯辽宁工程技术大学测绘与地理科学学院阜新123000 中国地质大学(北京)信息工程学院北京100083 南京航空航天大学航天学院南京210016 中国地震应急搜救中心北京100049 首都师范大学资源环境与旅游学院北京100048 中国空间技术研究院遥感卫星总体部北京100094

高分辨率遥感图像的缺失区域中地物种类复杂多样、空间异质性高,导致图像修复结果中存在纹理模糊和结构扭曲的问题,且在边界和复杂纹理区域尤为突出。因此提出一种结合空间语义注意力的二段式遥感图像修复网络。该网络由粗修复网络和精... 详细信息

高分辨率遥感图像的缺失区域中地物种类复杂多样、空间异质性高,导致图像修复结果中存在纹理模糊和结构扭曲的问题,且在边界和复杂纹理区域尤为突出。因此提出一种结合空间语义注意力的二段式遥感图像修复网络。该网络由粗修复网络和精修复网络串联而成,旨在使用粗略修复网络提供的先验信息,引导精修复网络对缺失区域的复原。在粗修复网络中,构建多级损失结构以强化网络训练的稳定性;在精修复网络中,提出一种新的空间语义注意力机制,并依据网络特征的分布特点,区别性将空间语义注意力嵌入在编码器和解码器中,以确保局部特征的连续性和全局语义信息的相关性。实验结果表明,所提方法相比于现有其他算法可以进一步提升图像修复效果。

关键词：二段式网络遥感图像修复空间语义注意力局部特征连续性全局语义信息相关性

Auto machine learning-based modelling and prediction of excavationinduced tunnel displacement

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Journal of Rock Mechanics and Geotechnical engineering 2022年第4期14卷 1100-1114页

作者： Dongmei Zhang Yiming Shen zhongkai Huang Xiaochuang Xie Key Laboratory of Geotechnical and Underground engineering Ministry of EducationTongji UniversityShanghai200092China Department of Geotechnical engineering College of Civil EngineeringTongji UniversityShanghai200092China

The influence of a deep excavation on existing shield tunnels nearby is a vital issue in tunnelling ***,there lacks robust methods to predict excavation-induced tunnel *** this study,an auto machine learning(AutoML)-based approach is proposed to precisely solve the *** input parameters are considered in the database covering two physical aspects,namely soil property,and spatial characteristics of the deep *** 10-fold cross-validation method is employed to overcome the scarcity of data,and promote model’s *** genetic algorithm(GA)-ML models are established as well for *** results indicated that the proposed AutoML model is a comprehensive model that integrates efficiency and *** analysis reveals that the ratio of the average shear strength to the vertical effective stress E_(ur)/σ′_(v),the excavation depth H,and the excavation width B are the most influential variables for the ***,the AutoML model is further validated by practical *** prediction results are in a good agreement with monitoring data,signifying that our model can be applied in real projects.

关键词： Soilestructure interaction Auto machine learning(AutoML) Displacement prediction Robust model Geotechnical engineering

Investigations of Thermal Deformation Based on the Monitoring System of Tianma 13.2 m VGOS Telescope

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Research in Astronomy and Astrophysics 2022年第9期22卷 35-46页

作者： Shize Song zhongkai Zhang Guangli Wang Yong Zheng Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 20030China university of Chinese Academy of Sciences Beijing.100049China Information engineering university Zhengzhou 450000China Henan Industrial Technology Academy of Spatio-Temporal Big Data Zhengzhou 450000China

The thermal expansion of radio telescopes has been recognized as a significant systematic error in Very Long Baseline Interferometry(VLBI) data analysis. Although the thermal expansion model recommended by International Earth Rotation Service(IERS) Conventions 2010 can achieve millimeter accuracy for the International VLBI Service for Geodesy and Astrometry(IVS) routine telescopes, both the International Terrestrial Reference Frame 2020(ITRF2020) in preparation and the VLBI2010 project encourage the scientific community to reconsider its modeling. To this end, we developed a monitoring system for the Tianma 13.2 m VLBI Global Observing System(VGOS) telescope. Based on the observed data, we refined the IERS expansion model, with results showing that the accuracy of our modified model was improved by 1.9 times. It suggested that the IERS thermal expansion model can achieve the declared millimeter accuracy, and refining its modeling can meet the requirement of 0.3 mm rms stability of the VGOS antenna reference point for the VLBI2010 project.

关键词： Astronomical Instrumentation Methods and Techniques methods:analytical methods:data analysis telescopes

Robust H_(∞)state estimation for a class of complex networks with dynamic event-triggered scheme against hybrid attacks

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Chinese Physics B 2022年第2期31卷 269-277页

作者： Yahan Deng zhongkai Mo Hongqian Lu School of Intelligent Systems engineering Guangxi City Vocational UniversityChongzuo 532200China

We investigate the dynamic event-triggered state estimation for uncertain complex networks with hybrid delays suffering from both deception attacks and denial-of-service ***,the effects of time-varying delays and finitedistributed delays are considered during data transmission between ***,a dynamic event-triggered scheme(ETS)is introduced to reduce the frequency of data transmission between sensors and ***,by considering the discussed plant,dynamic ETS,state estimator,and hybrid attacks into a unified framework,this framework is transferred into a novel dynamical ***,with the help of Lyapunov stability theory and linear matrix inequality techniques,sufficient condition to ensure that the system is exponentially stable and satisfies H∞performance constraints is obtained,and the design algorithm for estimator gains is ***,two numerical examples verify the effectiveness of the proposed method.

关键词： dynamic event-triggered scheme hybrid attacks complex networks state estimation

The action and analysis of magnetic field on the lubricants and wear products in the process of wearing

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Science China Mathematics 2001年第S1期44卷 267-272页

作者： ZHOU Qiang XU Ruiqing Mechanical engineering College, China agriculture university, Beijing 100083, China China Agr Univ Mech Engn Coll Beijing 100083 Peoples R China

The magnetic field is an important factor in the conditioning and controlling tribologicalproperty. This paper analyzes and describes the physical effects and chemical natures of magneticfield to affect the friction, wear and lubrication, and characterize the tribochemical effect of mag-netic field on WRL lubricant by infrared(IR) spectrum method. At same time, the tribological prop-erty of WRL lubricant was examined by using the reciprocating friction-wear tester of NG-x type inthe condition of magnetic field. The results show that the present of magnetic field can decreasethe friction coefficient(f) and wear weight(W), even realize the zero-wear testing situation.

关键词： magnetic field friction and wear lubricant boundary film micro-particles alkylated metal micro-debris

波纹几何参数对波纹轧钛/钢复合板抗冲击性能的影响

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包装工程 2024年第19期45卷 65-73页

作者：任路泽梁子睿卢传浩任忠凯曹勇太原理工大学机械与运载工程学院应用力学研究所太原030024 太原理工大学先进金属复合材料成形技术与装备教育部工程研究中心太原030024

目的为了探究波纹轧钛/钢复合板的抗冲击性能,对比分析不同的波纹几何参数对钛/钢复合板抗冲击性能的影响。方法使用一级空气炮发射球形弹丸对波纹轧制钛/钢复合板进行弹道冲击试验,利用数字图像相关(Digital Image Correlation,DIC)技... 详细信息

目的为了探究波纹轧钛/钢复合板的抗冲击性能,对比分析不同的波纹几何参数对钛/钢复合板抗冲击性能的影响。方法使用一级空气炮发射球形弹丸对波纹轧制钛/钢复合板进行弹道冲击试验,利用数字图像相关(Digital Image Correlation,DIC)技术计算复合板的挠度,分析弹道冲击下钛/钢复合板的变形特征和损伤机理。使用LS-DYNA建立数值模型,在验证模型可行性的基础上,改变模型中的波纹几何参数,探究不同波幅和周期对钛/钢复合板抗冲击性能的影响。结果小能量冲击下,钛/钢复合板抗冲击机制主要是通过复合板的塑性变形来吸收能量,形成塑性开坑变形,且在层间结合处并未发生明显分层现象。结论工艺参数允许的情况下,增大波幅和减少周期均可提高复合板的抗冲击性能,这是因为大波幅和小周期结构可以增加复合板异质材料的接触面积,提高层间结合力,从而提升复合板抗冲击变形和分层的性能。

关键词：钛/钢复合板抗冲击性能数值模型波纹几何参数