检索结果-内蒙古大学图书馆

adaptive fault-tolerant visual control of robot manipulators using an uncalibrated camera

NONLINEAR DYNAMICS 2023年第4期111卷 3379-3392页

作者： Yang, Liang Yuan, Can Lai, Guanyu China Zhongshan Inst Sch Comp Engn Univ Elect Sci & Technol Zhongshan 528402 Guangdong Peoples R China Guangdong Univ Technol Sch Automat Guangzhou 510006 Guangdong Peoples R China

In this paper, we propose an adaptive fault-tolerant visual control scheme for robotic manipulators with possible actuator failures in an uncalibrated environment. Most existing visual control approaches for robot system do not take into account actuator failures, which may prominently affect the transient performance of the system in practice. In order to moderate the detrimental and adverse effects of actuator failures on the system, a new adaptive algorithm is proposed to compensate stuck-type failures occurred in actuators. Moreover, by proposing a decoupling method, the uncertain parameter model of actuator failure is successfully separated from the dynamics model while the two models are coupled in most existing results [e.g., (Rugthum and Tao in Robotica 34(7):1529-1552, 2016;Rugthum in: International conference on engineering, applied sciences, and technology (ICEAST), pp 1-4, 2018)]. And the stability of the dynamic system and the convergence of the image error are proved by the Lyapunov analysis method. Finally, the effectiveness of the proposed control scheme is verified by comparing and analysing the tracking performance of the 3-DOF manipulator under different failure parameters.

关键词： Actuator failure compensation Visual servoing adaptive control adaptive algorithm 3-DOF manipulator

来源：评论

学校读者我要写书评

暂无评论

adaptive Backoff algorithm for EDCA in the IEEE 802.11p protocol

Adaptive Backoff Algorithm for EDCA in the IEEE 802.11p prot...

引用

International Wireless Communications and Mobile Computing Conference

作者： Yamen Y. Nasrallah Irfan Al-Anbagi Hussein T. Mouftah School of Electrical Engineering and Computer Science University of Ottawa Faculty of Engineering and Applied Science University of Regina

ISBN: (纸本)9781509003051

The Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is an integrated algorithm employed in the Enhanced Distributed Channel Access (EDCA) in the IEEE 802.11p protocol. CSMA/CA manages the access of packets to the medium and its main role is to avoid collisions among them. An essential process of CSMA/CA is the backoff period in which the packets has to wait for a random number of Time Slots (TS) before attempting to access the medium. The backoff operation is based on a simple deterministic approach that does not consider the status of the medium at the time of transmission. In this paper, we propose an adaptive Backoff algorithm (ABA). ABA is based on a probabilistic approach that takes into account the current situation of the medium. ABA is calculated as a function of the packets probability of collision. We present two algorithms ABA1 and ABA2, the function of the former is directly proportional to the collision probability however the function of the latter is exponentially dependent on the collision probability. We develop a Markov-based analytical model to evaluate ABA1 and ABA2, and study the performance of each system.

关键词： VANET CSMA/CA adaptive algorithm Markov chain Analytical model IEEE 802.11p EDCA

来源：评论

学校读者我要写书评

暂无评论

adaptive Exact Penalty Design for Optimal Resource Allocation

引用

IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 2023年第3期34卷 1430-1438页

作者： Lian, Mengke Guo, Zhenyuan Wang, Xiaoxuan Wen, Shiping Huang, Tingwen Hunan Univ Sch Math Changsha 410082 Hunan Peoples R China Hunan Univ Hunan Prov Key Lab Intelligent Informat Proc & Ap Changsha 410082 Hunan Peoples R China Huazhong Univ Sci & Technol Sch Automat Wuhan 430074 Peoples R China Texas A&M Univ Qatar Sci Program Doha Qatar

In this article, a distributed adaptive continuous-time optimization algorithm based on the Laplacian-gradient method and adaptive control is designed for resource allocation problem with the resource constraint and the local convex set constraints. In order to deal with local convex sets, a distance-based exact penalty function method is adopted to reformulate the resource allocation problem instead of the widely used projection operator method. By using the nonsmooth analysis and set-valued LaSalle invariance principle, it is proven that the proposed algorithm is capable of solving the nonsmooth resource allocation problem. Finally, two simulation examples are presented to substantiate the theoretical results.

关键词： Resource management Linear programming Heuristic algorithms Laplace equations Cost function Learning systems Eigenvalues and eigenfunctions adaptive algorithm distributed optimization nonsmooth analysis resource allocation

来源：评论

学校读者我要写书评

暂无评论

Optimized adaptive algorithm of Digital Selfinterference Cancellation Based on Improved Variable Step

Optimized Adaptive Algorithm of Digital Selfinterference Can...

引用

2015 IEEE 9th International Conference on Anti-counterfeiting,Security, and Identification(ASID)

作者： Lingyun Sun Yujie Li Yifeng Zhao Lianfen Huang Zhibin Gao Department of Communication Engineering Xiamen University

Full-duplex wireless communication system transmits and receives signals in a same frequency band and at a same time, which solves the problem of the low using efficiency of limited radio spectrum resource, and doubles the channel capacity. However, it also brings a new problem that the full-duplex node will generate a strong self-interference signal. And to deal with the self-interference signal, using existing negative selfinterference cancellation and analog self-interference cancellation technology are not enough, effective digital selfinterference cancellation is needed for further cancellation. This paper proposes an optimized adaptive algorithm of digital selfinterference cancellation based on improved variable step. By using a iteration threshold, we establish a new nonlinear relationship between the step factor and the error signal, which overcomes the slow change problem when the error signal is getting closed to zero, and accelerates the convergence rate.

关键词： component full-duplex digital self-interference cancellation adaptive algorithm step factor

来源：评论

学校读者我要写书评

暂无评论

Homogeneity Enforced Calibration of Stage Nonidealities for Pipelined ADCs

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 2023年第4期70卷 1286-1290页

作者： Wagner, Matthias Lang, Oliver Bauernfeind, Thomas Huemer, Mario Johannes Kepler Univ Linz Inst Signal Proc A-4040 Linz Austria Infineon Technol Austria AG Dev Ctr Linz A-4040 Linz Austria

Pipelined analog-to-digital converters (ADCs) are fundamental components of various signal processing systems requiring high sampling rates and a high linearity. Over the past years, calibration techniques have been intensively investigated to increase the linearity. In this brief, we propose an equalization-based calibration technique which does not require knowledge of the ADC input signal for calibration. For that, a test signal and a scaled version of it are fed into the ADC sequentially, while only the corresponding output samples are used for calibration. Several test signal sources are possible, such as a signal generator (SG) or the system application (SA) itself. For the latter case, the presented method corresponds to a background calibration technique. Thus, slowly changing errors are tracked and calibrated continuously. Because of the low computational complexity of the calibration technique, it is suitable for an on-chip implementation. Ultimately, this brief contains an analysis of the stability and convergence behavior as well as simulation results.

关键词： Calibration Linearity Convergence Quantization (signal) Voltage Hardware Computational modeling Pipelined ADC ADC calibration equalization-based background calibration adaptive algorithm

来源：评论

学校读者我要写书评

暂无评论

Actuator Fault Estimation Based On adaptive Iterative Learning algorithm For Nonlinear Periodic Systems 40

Actuator Fault Estimation Based On Adaptive Iterative Learni...

引用

40th Chinese Control Conference (CCC)

作者： Liu, Ya-qi Fang, Yi-ming Liu, Le Li, Xing-da Yanshan Univ Key Lab Ind Comp Control Engn Hebei Prov Qinhuangdao 066004 Hebei Peoples R China Yanshan Univ Educ Minist Intelligent Control Syst & Intelligen Engn Res Ctr Qinhuangdao 066004 Hebei Peoples R China

ISBN: (纸本)9789881563804

A actuator fault estimation algorithm based on adaptive iterative learning is proposed for a class of nonlinear periodic systems with actuator fault and disturbances. Firstly, the proposed method designs a state observer and a fault estimator based on adaptive iterative learning. The Lyapunov stability theory and the optimization theory are employed to prove the convergence of the method. Then the LMI toolbox is utilized to obtain the results of the observer gain matrix and fault estimator parameter matrix. The method combines the iterative learning strategy with the adaptive algorithm, and utilizes not only the state error signals of the last iteration learning, but also the output error signals of this time. It makes the estimated fault approximate to the real fault gradually and realizes the accurate estimation of the time-varying fault and the intermittent fault. Finally, the validity and accuracy of the proposed method are verified by the simulation of a single-link robotic arm mold.

关键词： Iterative learning scheme adaptive algorithm Fault estimation Actuator fault Linear matrix inequality

来源：评论

学校读者我要写书评

暂无评论

AptBLE: adaptive PHY Mode based on K-means algorithm in Bluetooth5 20

AptBLE: Adaptive PHY Mode based on K-means Algorithm in Blue...

引用

12th Annual Wireless Telecommunications Symposium (WTS)

作者： Luo, Xuan Zang, Mingyuan Yan, Ying Dittmann, Lars Tech Univ Denmark Dept Photon Engn Lyngby Denmark

ISBN: (纸本)9781728184807

Since Bluetooth5 standard released in 2016, its usage in commercial electronic products has been increased rapidly and substantially. Comparing to BLE 4.2, Bluetooth5 supports three PHY modes, respectively 2M, 1M and Coded PHY mode, providing a higher throughput and a wider range. Whereas there is a trade-off between its throughput and coverage. When the connection is established, the PHY mode is commonly pre-configured and fixed. This rigid design limits the flexibility in offering dynamic throughput and coverage. Therefore, we propose a method termed AptBLE, that switches the PHY mode in Bluetooth5 adaptively by considering the Received Signal Strength Indicator (RSSI) level. Specifically, we optimise the RSSI threshold for different PHY modes using the K-means clustering algorithm. Moreover, based on AptBLE, we further enable the Data Length Extension (DLE) feature and term the improved method as AptBLEM. We implement AptBLE (M) on the boards and test in indoor environment. The experimental results show that, AptBLE is more flexible, robust and outperforms the original fixed PHY mode in terms of throughput and transmission range. Furthermore, AptBLEM can triple the throughput than AptBLE, with a maximum throughput value in 1035Kbps and 42m range in indoor environment.

关键词： Bluetooth5 Internet of Things machine learning algorithm RSSI indoor measurement adaptive algorithm

来源：评论

学校读者我要写书评

暂无评论

adaptive Air Charge Estimation algorithm for Lean Burn SI Engines 6th

Adaptive Air Charge Estimation Algorithm for Lean Burn SI En...

引用

6th IFAC Conference on Engine Powertrain Control, Simulation and Modeling (E-COSM)

作者： Khajorntraidet, Chanyut Chaiyanupong, Jaruwan King Mongkuts Univ Technol North Bangkok Fac Engn & Technol Rayong Campus Bangkok Thailand

The accuracy of cylinder air charge direct measurement affects air-fuel ratio (AFR) control performance and exhaust emissions of internal combustion engines, especially during the transient response. In lean combustion control, the combustion variation is higher than the normal combustion. Accurate air charge estimation is crucial in this combustion mode. Therefore, the methodology for the improvement of cylinder air charge estimation is required. With the effective air charge estimation method, the feedforward control of fuel injection can be precisely performed. This paper studies the performance of the adaptive air charge estimation algorithm on the lean operation mode. The results show that the applied algorithm is robust and has high efficiency for the cylinder air charge estimation. Copyright (C) 2021 The Authors.

关键词： adaptive algorithm cylinder air charge estimation lean combustion SI engines

来源：评论

学校读者我要写书评

暂无评论

An adaptive User Tracking algorithm Using Irregular Data Frames for Passive Fingerprint Positioning

引用

SENSORS 2022年第19期22卷 7124-7124页

作者： Kim, Donghyun Son, Kyuho Han, Dongsoo Korea Adv Inst Sci & Technol Sch Comp Daejeon 34141 South Korea

Wi-Fi fingerprinting is the most popular indoor positioning method today, representing received signal strength (RSS) values as vector-type fingerprints. Passive fingerprinting, unlike the active fingerprinting method, has the advantage of being able to track location without user participation by utilizing the signals that are naturally emitted from the user's smartphone. However, since signals are generated depending on the user's network usage patterns, there is a problem in that data are irregularly collected according to the patterns. Therefore, this paper proposes an adaptive algorithm that shows stable tracking performances for fingerprints generated at irregular time intervals. The accuracy and stability of the proposed tracking method were verified by experiments conducted in three scenarios. Through the proposed method, it is expected that the stability of indoor positioning and the quality of location-based services will improve.

关键词： indoor positioning passive fingerprinting user tracking adaptive algorithm location based service

来源：评论

学校读者我要写书评

暂无评论

A Multigrid Discretization of Discontinuous Galerkin Method for the Stokes Eigenvalue Problem

引用

Communications in Computational Physics 2023年第10期34卷 1391-1419页

作者： Ling Ling Sun Hai Bi Yidu Yang School of Mathematical Sciences Guizhou Normal UniversityGuiyang550001China School of Biology and Engineering Guizhou Medical UniversityGuiyang550001China

In this paper,based on the velocity-pressure formulation of the Stokes eigenvalue problemin d-dimensional case(d=2,3),we propose amultigrid discretization of discontinuous Galerkin method using P_(k)-P_(k)-1 element(k≥1)and prove its a priori error *** also give the a posteriori error estimators for approximate eigenpairs,prove their reliability and efficiency for eigenfunctions,and also analyze their reliability for *** implement adaptive calculation,and the numerical results confirm our theoretical predictions and show that our method is efficient and can achieve the optimal convergence order O(do f-2k/d).

关键词： Stokes eigenvalue problem discontinuous Galerkin method multigrid discretizations adaptive algorithm

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：