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Knowledge Fusion and Synchronization over Ubiquitous Ontology Mapping 被引量:1
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作者 Hang Qin Li Zhu 《Journal of Computer and Communications》 2017年第10期1-9,共9页
With the rapid development and popularization of web services, the available information types and structure are becoming more and more complex and challenging. Actually web services involve the need for dynamic integ... With the rapid development and popularization of web services, the available information types and structure are becoming more and more complex and challenging. Actually web services involve the need for dynamic integration and transparent knowledge integration, in light of the urgent information changing track. Under this situation, the traditional search engine and information integration cannot finish this challenge, thereby bringing the opportunity for knowledge fusion and synchronization. This paper proposes a multi-matching strategy ontology mapping method for web information, i.e., ubiquitous ontology mapping method (U-Mapping), which can be viewed as a base collection of information on multiple ontologies made to appear anytime and everywhere. This approach is usually built independently by different information providers, avoiding the grammatical and semantic conflict. Finally, the ontology case information can be utilized under the consolidation of the U-Mapping, concerning language technology and machine learning methods. 展开更多
关键词 UBIQUITOUS Ontology mapping KNOWLEDGE FUSION Information Integration KNOWLEDGE synchronization CONCEPTUAL Space FUSION RULES
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Generalized synchronization between different chaotic maps via dead-beat control 被引量:2
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作者 Grassi G 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期100-106,共7页
This paper presents a new scheme to achieve generalized synchronization(GS) between different discrete-time chaotic(hyperchaotic) systems.The approach is based on a theorem,which assures that GS is achieved when a... This paper presents a new scheme to achieve generalized synchronization(GS) between different discrete-time chaotic(hyperchaotic) systems.The approach is based on a theorem,which assures that GS is achieved when a structural condition on the considered class of response systems is satisfied.The method presents some useful features:it enables exact GS to be achieved in finite time(i.e.,dead-beat synchronization);it is rigorous,systematic,and straightforward in checking GS;it can be applied to a wide class of chaotic maps.Some examples of GS,including the Grassi-Miller map and a recently introduced minimal 2-D quadratic map,are illustrated. 展开更多
关键词 generalized synchronization chaos synchronization discrete-time chaotic systems deadbeat control chaotic maps
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Partial and complete periodic synchronization in coupled discontinuous map lattices 被引量:2
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作者 杨科利 陈会云 +2 位作者 杜伟伟 金涛 屈世显 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期331-336,共6页
The partial and complete periodic synchronization in coupled discontinuous map lattices consisting of both discon- tinuous and non-invertible maps are discussed. We classify three typical types of periodic synchroniza... The partial and complete periodic synchronization in coupled discontinuous map lattices consisting of both discon- tinuous and non-invertible maps are discussed. We classify three typical types of periodic synchronization states, which give rise to different spatiotemporal patterns including static partial periodic synchronization, dynamically periodic syn- chronization, and complete periodic synchronization patterns. A special prelude dynamics of partial and complete periodic synchronization motion, which is shown by five separated concave curves in the time series plots of the order parameters, is observed. The detailed analysis shows that the special prelude dynamics is induced by the competition between two synchronized clusters, and the analytical expression for the corresponding order parameter is obtained. 展开更多
关键词 discontinuous map coupled map lattices periodic synchronization prelude dynamics
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Inverse full state hybrid projective synchronization for chaotic maps with different dimensions 被引量:3
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作者 Adel Ouannas Giuseppe Grassi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期251-256,共6页
A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach ... A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach enables each drive system state to be synchronized with a linear response combination of the response system states.The method,based on the Lyapunov stability theory and the pole placement technique,presents some useful features:(i) it enables synchronization to be achieved for both cases of n 〈 m and n 〉 m;(ii) it is rigorous,being based on theorems;(iii) it can be readily applied to any chaotic(hyperchaotic) maps defined to date.Finally,the capability of the approach is illustrated by synchronization examples between the two-dimensional H′enon map(as the drive system) and the three-dimensional hyperchaotic Wang map(as the response system),and the three-dimensional H′enon-like map(as the drive system) and the two-dimensional Lorenz discrete-time system(as the response system). 展开更多
关键词 chaotic map full state hybrid projective synchronization inverse problem maps with different dimensions
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Effects of Scale-Free Topological Properties on Dynamical Synchronization and Control in Coupled Map Lattices 被引量:1
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作者 CHEN Wei FANG Jin-Qing KANG Ge-Wen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期361-368,共8页
In the paper, we study effects of scale-free (SF) topology on dynamical synchronization and control in coupled map lattices (CIVIL). Our strategy is to apply three feedback control methods, including constant feed... In the paper, we study effects of scale-free (SF) topology on dynamical synchronization and control in coupled map lattices (CIVIL). Our strategy is to apply three feedback control methods, including constant feedback and two types of time-delayed feedback, to a small fraction of network nodes to reach desired synchronous state. Two controlled bifurcation diagrams verses feedback strength are obtained respectively. It is found that the value of critical feedback strength γc for the first time-delayed feedback control is increased linearly as e is increased linearly. The GML with SF loses synchronization and intermittency occurs if γ 〉 γc. Numerical examples are presented to demonstrate all results. 展开更多
关键词 scale-free network coupled map lattice dynamical synchronization feedback control timedelayed feedback
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Synchronization–desynchronization transitions in networks of circle maps with sinusoidal coupling
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作者 翟云 肖井华 郑志刚 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期168-176,共9页
Coupled phase oscillators are adopted as powerful platforms in studying synchrony behaviors emerged in various systems with rhythmic dynamics. Much attention has been focused on coupled time-continuous oscillators des... Coupled phase oscillators are adopted as powerful platforms in studying synchrony behaviors emerged in various systems with rhythmic dynamics. Much attention has been focused on coupled time-continuous oscillators described by differential equations. In this paper, we study the synchronization dynamics of networks of coupled circle maps as the discrete version of the Kuramoto model. Despite of its simplicity in mathematical form, it is found that discreteness may induce many interesting synchronization behaviors. Multiple synchronization and desynchronization transitions of both phases and frequencies are found with varying the coupling among circle-map oscillators. The mechanisms of these transitions are interpreted in terms of the mean-field approach, where collective bifurcation cascades are revealed for coupled circle-map oscillators. 展开更多
关键词 synchronization circle map Kuramoto model BIFURCATION
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Measure Synchronization on Symplectic Map
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作者 CHENShao-Ying XUHai-Bo +1 位作者 WANGGuang-Rui CHENShi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期886-894,共9页
Measure synchronization in coupled Hamiltonian systems is a novel synchronization phenomenon. The measure synchronization on symplectic map is observed numerically, for identical coupled systems with different paramet... Measure synchronization in coupled Hamiltonian systems is a novel synchronization phenomenon. The measure synchronization on symplectic map is observed numerically, for identical coupled systems with different parameters. We have found the properties of the characteristic frequency and the amplitude of phase locking in regular motion when the measure synchronization of coupled systems is obtained. The relations between the change of the largest Lyapunov exponent and the course of phase desynchronization are also discussed in coupled systems, some useful results are obtained. A new approach is proposed for describing the measure synchronization of coupled systems numerically,which is advantage in judging the measure synchronization, especially for the coupled systems in nonregular region. 展开更多
关键词 symplectic map measure synchronization phase locking Lyapunov exponent
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Controlling and synchronizing spatiotemporal chaos of the coupled Bragg acousto-optical bistable map system using nonlinear feedback 被引量:12
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作者 岳立娟 沈柯 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1760-1765,共6页
In this paper we present the control and synchronization of a coupled Bragg acousto-optic bistable map system using nonlinear feedback technology. This nonlinear feedback technology is useful to control a temporally c... In this paper we present the control and synchronization of a coupled Bragg acousto-optic bistable map system using nonlinear feedback technology. This nonlinear feedback technology is useful to control a temporally chaotic system as well as a spatiotemporally chaotic system. It can be extended to synchronize the spatiotemporal chaos. It can work in a wide range of the controlled and synchronized signals, so it can decrease the sensitivity down to a noise level. The synchronization can be obtained by the analysis of the largest conditional Lyapunov exponent spectrum, and easily implemented in practical systems just by adjusting the coupled strength without any pre-knowledge of the dynamic system required. 展开更多
关键词 synchronization and control spatiotemporal chaos nonlinear feedback acousto-optic bistable map system
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Control and synchronization of second Julia sets 被引量:2
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作者 张永平 孙伟华 刘长安 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期146-153,共8页
A visualization of Julia sets of the complex Henon map system with two complex variables is introduced in this paper. With this method, the optimal control function method is introduced to this system and the control ... A visualization of Julia sets of the complex Henon map system with two complex variables is introduced in this paper. With this method, the optimal control function method is introduced to this system and the control and synchronization of its Julia sets are achieved. Control and synchronization of generalized Julia sets are also achieved with this optimal control method. The simulations illustrate the efficacy of this method. 展开更多
关键词 Henon map Julia set optimal control synchronization
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Function Projective Synchronization in Discrete-Time Chaotic System with Uncertain Parameters 被引量:1
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作者 CHEN Yong LI Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期470-474,共5页
The function projective synchronization of discrete-time chaotic systems is presented. Based on backstepping design with three controllers, a systematic, concrete and automatic scheme is developed to investigate funct... The function projective synchronization of discrete-time chaotic systems is presented. Based on backstepping design with three controllers, a systematic, concrete and automatic scheme is developed to investigate function projective synchronization (FPS) of discrete-time chaotic systems with uncertain parameters. With the aid of symbolic-numeric computation, we use the proposed scheme to illustrate FPS between two identical 3D Henon-like maps with uncertain parameters. Numeric simulations are used to verify the effectiveness of our scheme. 展开更多
关键词 function projective synchronization backstepping design discrete-time chaotic system Henon-like map
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Synchronization of spatiotemporal chaotic systems and application to secure communication of digital image
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作者 王兴元 张娜 +1 位作者 任小丽 张永雷 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期125-132,共8页
Coupled map lattices (CMLs) are taken as examples to study the synchronization of spatiotemporal chaotic systems. In this paper, we use the nonlinear coupled method to implement the synchronization of two coupled ma... Coupled map lattices (CMLs) are taken as examples to study the synchronization of spatiotemporal chaotic systems. In this paper, we use the nonlinear coupled method to implement the synchronization of two coupled map lattices. Through the appropriate separation of the linear term from the nonlinear term of the spatiotemporal chaotic system, we set the nonlinear term as the coupling function and then we can achieve the synchronization of two coupled map lattices. After that, we implement the secure communication of digital image using this synchronization method. Then, the discrete characteristics of the nonlinear coupling spatiotemporal chaos are applied to the discrete pixel of the digital image. After the synchronization of both the communication parties, the receiver can decrypt the original image. Numerical simulations show the effectiveness and the feasibility of the proposed program. 展开更多
关键词 coupled map lattice projective synchronization digital image secure communication
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Synchronizing spatiotemporal chaos in the coupled map lattices using nonlinear feedback functions 被引量:1
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作者 FangJin-Qing MKAli 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第3期129-135,共7页
SynchronizingspatiotemporalchaosinthecoupledmaplaticesusingnonlinearfedbackfunctionsTheworkissupportedbyfund... SynchronizingspatiotemporalchaosinthecoupledmaplaticesusingnonlinearfedbackfunctionsTheworkissupportedbyfundingtoFangJinQi... 展开更多
关键词 浑沌 同步时空浑沌 非线性反馈函数
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Generalized Synchronization of Time-Delayed Discrete Systems
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作者 JING Jian-Yi MIN Le-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期1149-1152,共4页
This paper establishes two theorems for two time-delayed (chaotic) discrete systems to achieve timedelayed generalized synchronization (TDGS). These two theorems uncover the genera/forms of two TDGS systems via a ... This paper establishes two theorems for two time-delayed (chaotic) discrete systems to achieve timedelayed generalized synchronization (TDGS). These two theorems uncover the genera/forms of two TDGS systems via a prescribed transformation. As examples, we convert the Lorenz three-dimensional chaotic map to an equal time-delayed system as the driving system, and construct the TDGS driven systems according to the Theorems 1 and 2. Numerical simulations demonstrate the effectiveness of the proposed theorems. 展开更多
关键词 generalized synchronization time-delayed systems Lorenz three-dimensional chaotic map
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Function Projective Synchronization of Discrete-Time Chaotic and Hyperchaotic Systems Using Backstepping Method
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作者 JIN Yi-Liang LI Kin CHEN Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期111-116,共6页
In this paper, a function projective synchronization scheme is developed to investigate the function projective synchronization between the discrete-time driven chaotic system and the discrete-time response chaotic sy... In this paper, a function projective synchronization scheme is developed to investigate the function projective synchronization between the discrete-time driven chaotic system and the discrete-time response chaotic system. With the aid of symbolic-numeric computation, we use the scheme to study the function projective synchronization between 2D Lorenz discrete-time system and Hdnon discrete-time system, as well as that between 3D discrete-time hyperchaotic system and Henon-like map via three scalar controllers, respectively. Moreover numerical simulations are used to verify the effectiveness of the proposed scheme. 展开更多
关键词 discrete-time chaotic system discrete-time chaotic map symbolic-numeric computation function projective synchronization backstepping design
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A Non-symmetric Digital Image Secure Communication Scheme Based on Generalized Chaos Synchronization System
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作者 ZHANG Xiao-Hong MIN Le-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期1115-1124,共10页
Based on a generalized chaos synchronization system and a discrete Sinai map, a non-symmetric true color (RGB) digital image secure communication scheme is proposed. The scheme first changes an ordinary RGB digital ... Based on a generalized chaos synchronization system and a discrete Sinai map, a non-symmetric true color (RGB) digital image secure communication scheme is proposed. The scheme first changes an ordinary RGB digital image with 8 bits into unrecognizable disorder codes and then transforms the disorder codes into an RGB digital image with 16 bits for transmitting. A receiver uses a non-symmetric key to verify the authentication of the received data origin, and decrypts the ciphertext. The scheme can encrypt and decz:Fpt most formatted digital RGB images recognized by computers, and recover the plaintext almost without any errors. The scheme is suitable to be applied in network image communications. The analysis of the key space, sensitivity of key parameters, and correlation of encrypted images imply that this scheme has sound security. 展开更多
关键词 generalized chaos synchronization Sinai map image confusion non-symmetric key data origin authentication network communication
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基于改进Gmapping的室内ROS智能车同步定位与建图系统设计 被引量:4
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作者 闫鹏 林迎春 《汽车实用技术》 2023年第19期61-66,共6页
室内移动机器人是近年来研究的热点问题,同步定位与建图技术更是移动机器人的关键技术之一。为此文章设计了基于机器人操作系统(ROS)智能车的同步定位与建图系统,以Gmapping为核心算法,首先采用电机编码器构建的里程计对单线激光雷达的... 室内移动机器人是近年来研究的热点问题,同步定位与建图技术更是移动机器人的关键技术之一。为此文章设计了基于机器人操作系统(ROS)智能车的同步定位与建图系统,以Gmapping为核心算法,首先采用电机编码器构建的里程计对单线激光雷达的每帧数据进行运动畸变补偿,以运动畸变补偿后的激光雷达数据和里程计数据作为Gmapping算法输入;然后通过Gmapping算法粒子初始化,构建考虑观测量的提议分布并对粒子进行采样以估计智能车位姿,以重采样重要性系数对粒子进行重采样并设置重采样阀值,利用二值贝叶斯滤波器对每个粒子的地图状态更新;最后基于Gmapping算法输出智能车的位姿估计和地图数据。试验结果表明,所设计的同步定位与建图系统,在小尺寸环境下对智能车位姿估计和构建的地图较为准确,满足设计目标要求。 展开更多
关键词 室内ROS智能车 Gmapping算法 同步定位与建图系统 激光雷达
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基于快速效率MAP图的外转子永磁同步电机优化设计 被引量:2
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作者 刁星鹏 黄颖 《汽车实用技术》 2024年第10期16-22,共7页
电动汽车复杂的运行工况要求驱动电机转速-转矩范围和高效率区范围宽,而电机效率MAP图是评估驱动电机是否满足上述要求最直观的工具。但是,电机效率MAP图通常需要台架测试来获取,费时费力,无法满足电动汽车敏捷开发过程中进行快速验证... 电动汽车复杂的运行工况要求驱动电机转速-转矩范围和高效率区范围宽,而电机效率MAP图是评估驱动电机是否满足上述要求最直观的工具。但是,电机效率MAP图通常需要台架测试来获取,费时费力,无法满足电动汽车敏捷开发过程中进行快速验证和优化迭代的要求。为解决这一问题,文章对轮毂电机中使用的外转子永磁同步电机,通过等效磁路法计算电机电磁参数值,再结合电机控制方法对电机全转速-转矩区间损耗进行计算,最后在MATLAB中编程实现电机效率MAP图的快速计算。基于此方法,结合遗传算法,可以实现电机结构参数的快速优化设计,进而提高产品开发效率。 展开更多
关键词 电动汽车 永磁同步电机 效率map 等效磁路法
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高通讯时延下融合车道级地图的车路协同感知定位方法
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作者 胡钊政 胡华桦 +2 位作者 孟杰 陈琪莉 张佳楠 《汽车工程》 北大核心 2025年第4期598-613,共16页
在车路协同技术运用于路侧孪生地图动态显示中,由于网联设备之间的通讯存在的时延问题及路侧感知误差的存在,对路侧边缘计算单元融合感知精度会产生严重影响,进而导致孪生地图中车辆显示轨迹出现抖动和延迟的现象。为此,本文提出了一种... 在车路协同技术运用于路侧孪生地图动态显示中,由于网联设备之间的通讯存在的时延问题及路侧感知误差的存在,对路侧边缘计算单元融合感知精度会产生严重影响,进而导致孪生地图中车辆显示轨迹出现抖动和延迟的现象。为此,本文提出了一种在高通讯时延下融合车道级地图的车路协同感知定位方法。该方法首先针对车路协同系统中智能网联汽车车端与路侧边缘处理单元之间的通讯时延问题进行分析建模,将延迟模型划分为异构传感器频率同步延迟以及通讯传输延迟,并提出了一种同步优化方法。在同步优化后,提出一种面向群车协同的多维度群车粒子滤波算法,其中粒子的状态量表示群车的状态信息。在所提出的多维度群车粒子滤波算法中首先使用利用路侧部分的观测数据和车道级地图中车道线朝向信息,对粒子的状态进行观测更新。然后利用接收到时延同步后的智能网联汽车的自定位信息和左右车道线横向观测信息与车道级地图中车道线方程对粒子中表示智能网联汽车状态的部分进行观测更新。实验结果显示,在通讯干扰较少的低时延场景中,边缘计算单元的感知定位准确度提升59.4%,在通讯干扰严重的高时延场景中,其准确度提升38.6%。因此所提出高通讯时延下融合车道级地图的车路协同感知定位方法可以有效处理通讯延时问题,并提升边缘计算单元多车感知定位精度进而提升孪生地图动态数据的准确性、稳定性和连续性。 展开更多
关键词 时延同步 车路协同 车道级地图 粒子滤波
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基于UeDiff-GAN的综采工作面目标检测与孪生体同步映射
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作者 张帆 于洋 +7 位作者 戚振明 李海军 王春丽 杜潇 王柄印 张光磊 宋惠 席宸荣 《工矿自动化》 北大核心 2025年第3期9-15,21,共8页
矿井综采工作面数字孪生模型的构建过程需要手动构建实体的数字孪生3D模型,然后对实体进行目标检测,并根据实时检测结果控制3D模型,以确保孪生体与实体之间的同步映射关系。因此,对井下目标的实时、准确检测是实现虚实同步映射控制的关... 矿井综采工作面数字孪生模型的构建过程需要手动构建实体的数字孪生3D模型,然后对实体进行目标检测,并根据实时检测结果控制3D模型,以确保孪生体与实体之间的同步映射关系。因此,对井下目标的实时、准确检测是实现虚实同步映射控制的关键。目前主流的目标检测方法需要在传统模型中引入或改进模块,使得模型网络结构复杂、训练周期较长,降低了目标检测的实时性;同时,对于一些含高强度噪声的图像难以精确检测。针对上述问题,提出了一种基于UeDiff-GAN的综采工作面目标检测与孪生体同步映射方法。通过扩散模型对高质量样本进行加噪扩散,得到不同程度的加噪样本,然后使用生成对抗网络(GAN)模型进行训练;设计了平滑扩散算法,以控制扩散步长,加入不均衡扩散模块,以得到与预识别样本匹配的检测算法模型。使用Unity3D构建综采工作面3D模型并进行渲染,实现井下物理实体的对象孪生,据此构建综采工作面实体与其孪生模型的映射关系,根据井下不同位置的检测结果控制对应机器运动状态及姿态,实现孪生模型协同控制,从而实现过程孪生。在自制数据集上的实验结果表明:UeDiff-GAN模型对井下移动目标的平均检测精度较SSD,R-CNN,YOLOv7和Diff-GAN模型分别提升了19.4%,14.3%,9.1%,24.3%;检测速度较SSD,R-CNN分别提升了13.86,42.73帧/s;孪生模型与实体的实时性延迟至多为0.873 s。 展开更多
关键词 综采工作面 数字孪生 目标检测 虚实同步映射 扩散模型 生成对抗网络
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基于改进海象优化算法的永磁同步电机参数辨识
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作者 谭舜 范必双 《制造技术与机床》 北大核心 2025年第9期129-136,共8页
针对永磁同步电机(permanent magnet synchronous motor,PMSM)参数辨识中存在的辨识速度慢、辨识误差较大等问题,提出一种改进海象优化算法(improved walrus optimization algorithm,IWaOA)用于参数辨识。该算法使用改进后的Circle混沌... 针对永磁同步电机(permanent magnet synchronous motor,PMSM)参数辨识中存在的辨识速度慢、辨识误差较大等问题,提出一种改进海象优化算法(improved walrus optimization algorithm,IWaOA)用于参数辨识。该算法使用改进后的Circle混沌映射产生海象种群以提高初始解的质量;在海象个体的觅食阶段引入黑寡妇算法中信息素的概念,提高算法全局寻优能力;提出一种融合异常值边界和贪婪规则的三角形游走策略对海象种群领导者所在的区域进行搜索,提高算法局部探索能力。建立永磁同步电机模型并使用IWaOA算法对电机的定子电阻、d-q轴电感、永磁体磁链进行辨识。仿真实验结果显示,IWaOA算法对4个参数的辨识误差均在0.2%以内,其中最小辨识误差低于0.02%,验证了所提算法用于永磁同步电机参数辨识的有效性和可靠性。 展开更多
关键词 永磁同步电机 群智能优化 参数辨识 混沌映射 信息素
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