检索结果-内蒙古大学图书馆

Stability and stabilisation of heterogeneous switched systems with arbitrary switching constraints

IET CONTROL THEORY AND APPLICATIONS 2020年第15期14卷 2049-2063页

作者： Yu, Shaohang Wu, Chengfu Wu, Jia-Nan Wang, Liang Northwestern Polytech Univ Sch Automat Xian 710065 Peoples R China Northwestern Polytech Univ Natl Key Lab Sci & Technol UAV Xian 710065 Peoples R China

Heterogeneous switched systems are a class of special hybrid systems containing different dimensional subsystems. To research the stability and stabilisation of heterogeneous switched systems, a novel approach is presented to design static output feedback controllers for asymptotically stabilising heterogeneous continuous-time and discrete-time switched systems under arbitrary switching rules. This approach, which has less computation complexity, includes a main diagonal square block common Lyapunov function for stability analysis of heterogeneous switched systems and a main diagonal square block common homogeneous polynomial Lyapunov function for stabilisation of heterogeneous switched systems. In the study of stabilisation of heterogeneous switched systems, a two-step iterative method including two convex optimisation functions is established by sums of squares to express existing properties condition and solvable properties condition for determining block controller. At last, a practical example and two numerical examples are presented to show the feasibility of the proposed results.

关键词： feedback control system synthesis discrete time systems iterative methods asymptotic stability Lyapunov methods polynomials switching systems (control) computational complexity continuous time systems convex programming discrete-time switched systems heterogeneous switched systems stabilisation arbitrary switching constraints hybrid systems static output feedback controllers design heterogeneous continuous-time systems asymptotic stability analysis arbitrary switching rules computation complexity diagonal square block common homogeneous polynomial Lyapunov function two-step iterative method convex optimisation functions block controller

来源：评论

学校读者我要写书评

暂无评论

A power-efficient ZF precoding scheme for multi-user indoor visible light communication systems

引用

OPTICS COMMUNICATIONS 2017年 384卷 101-106页

作者： Zhao, Qiong Fan, Yangyu Deng, Lijun Kang, Bochao Northwestern Polytech Univ Sch Elect & Informat Xian Shannxi Peoples R China

In this study, we propose a power-efficient ZF precoding scheme for visible light communication (VLC) downlink multi-user multiple-input-single-output (MU-MISO) systems, which incorporates the zero-forcing (ZF) and the characteristics of VLC systems. The main idea of this scheme is that the channel matrix used to perform pseudoinverse comes from the set of optical Access Points (APs) shared by more than one user, instead of the set of all involved serving APs as the existing ZF precoding schemes often used. By doing this, the waste of power, which is caused by the transmission of one user's data in the un-serving APs, can be avoided. In addition, the size of the channel matrix needs to perform pseudoinverse becomes smaller, which helps to reduce the computation complexity. Simulation results in two scenarios show that the proposed ZF precoding scheme has higher power efficiency, better bit error rate (BER) performance and lower computation complexity compared with traditional ZF precoding schemes.

关键词： Visible light communication (VLC) Multi-user multiple-input single-output (MUMISO) Precoding Zero forcing (ZF) Power efficiency computation complexity

来源：评论

学校读者我要写书评

暂无评论

Reconstruct unrecoverable data in real-time networks using Bezier curve

引用

IET COMMUNICATIONS 2015年第5期9卷 596-602页

作者： Nugroho, Dwi Agung Rizal, Syamsul Kim, Dong-Seong Kumoh Natl Inst Technol Dept IT Convergence Engn Sch Elect Engn Gumi Si South Korea

This study proposes a method to handle unrecoverable data using a formula called Bezier curve. The proposed method suggests the possibility to approximate the damaged data, which have been processed by the error correction scheme. The proposed method works on the real-time distributed system which retransmission is considered as unsuitable solution to manage the overall networked system. By using the Bezier curve, the transmitted unrecoverable data are reconstructed again by using the functional approximation. This method provides a smoothing effect on damaged data that usually are normalised on real-time transmission of PROFIBUS. Three differences Bezier curve methods are compared in PROFIBUS data, four-points (FP) method, two-points two-degrees method and four-degrees (FD) method. Simulation results show that all three Bezier curve methods can approximate data in PROFIBUS. FD has higher computation complexity compared with others. However, FD compensates with its data size which is only half of FP method.

关键词： computational geometry function approximation computational complexity data handling transmitted unrecoverable data reconstruction real-time networks Bezier curve unrecoverable data handling damaged data approximation error correction scheme real-time distributed system data retransmission overall networked system management functional approximation smoothing effect normalisation real-time PROFIBUS transmission four-point method two-point-two-degree method four-degree method FD method computation complexity data size FP method

来源：评论

学校读者我要写书评

暂无评论

Distributed testing on mutual independence of massive multivariate data

引用

COMMUNICATIONS IN STATISTICS-THEORY AND METHODS 2023年第15期52卷 5332-5348页

作者： Kuang, Yongxin Xie, Junshan Henan Univ Sch Math & Stat Kaifeng 475000 Peoples R China

The article considers a distributed divide-and-conquer method to test the mutual independence between components of massive multivariate data. In particular, a new test statistic based on U-statistics by dividing the full data samples into disjoint blocks will be established. Some numerical simulations and real data analysis demonstrate that the proposed method is effective, and it can significantly reduce the computational complexity and save the running time of the test procedure on massive data inference.

关键词： Mutual independence divide-and-conquer method symmetric measure computation complexity

来源：评论

学校读者我要写书评

暂无评论

Outage performance for amplify-and-forward two-hop multiple-access channel with noisy relay and interference-limited destination

引用

IET COMMUNICATIONS 2018年第2期12卷 205-213页

作者： Su, Yuping Li, Ying Wu, Xiaojun Liu, Lei Shaanxi Normal Univ Key Lab Modern Teaching Technol Minist Educ Xian 710062 Shaanxi Peoples R China Shaanxi Normal Univ Sch Comp Sci Xian 710119 Shaanxi Peoples R China Xidian Univ State Key Lab ISN Xian 710071 Shaanxi Peoples R China

The common outage performance of an amplify-and-forward two-hop two-user channel is studied in the presence of multiple independent interferers at the destination. First, the exact integral form expression of the common outage probability is derived. Then, in order to decrease the computation complexity, a closed-form approximation of the common outage probability is derived. Finally, the asymptotic analysis is performed based on the approximation expression. Numerical results demonstrate that the integral form of the common outage probability, the corresponding approximation and the asymptotic results match well with the Monte Carlo simulations.

关键词： telecommunication network reliability amplify and forward communication multi-access systems multiuser channels relay networks (telecommunication) radiofrequency interference probability computational complexity approximation theory Monte Carlo methods wireless channels amplify-and-forward two-hop multiple access channel noisy relay interference-limited destination amplify-and-forward two-hop two-user channel outage performance multiple independent interferer common outage probability exact integral form expression computation complexity common outage probability closed-form approximation asymptotic analysis Monte Carlo simulations

来源：评论

学校读者我要写书评

暂无评论

Transform-Exempted Calculation of Sum of Absolute Hadamard Transformed Differences

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2009年第8期19卷 1183-1188页

作者： Zhu, Ce Xiong, Bing Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

Sum of absolute Hadamard transformed differences (SATD) is an important distortion metric applied in the latest video coding standard H.264/AVC, which is an alternative to the sum of absolute differences (SAD) to improve coding efficiency. However, the SATD requires more computation load due to the Hadamard transform involved. Inspired by a geometric interpretation of the simplest two-point SATD calculation, an efficient way to compute the SATD is proposed, which considers the joint effect of the Hadamard transform and the following SAD processing in the SATD calculation and thus enables the computation of SATD without performing the Hadamard transform separately. We further extend the two-point transform-exempted SATD (TE-SATD) computation scheme to four-point and 4 x 4 block SATD calculation. With the same coding performance, the proposed TE-SATD-based fast algorithms can save 38% and 17% operations in computing a 4 x 4 block SATD compared with the conventional SATD calculation and the fast Hadamard transform-based calculation, respectively.

关键词： computation complexity fast algorithm H.264/AVC Hadamard transform sum of absolute difference (SAD) sum of absolute transformed difference (SATD)

来源：评论

学校读者我要写书评

暂无评论

3D Point Cloud-Based Indoor Mobile Robot in 6-DoF Pose Localization Using a Wi-Fi-Aided Localization System

引用

IEEE ACCESS 2021年 9卷 38636-38648页

作者： Shu, Mingcong Chen, Guoliang Zhang, Zhenghua China Univ Min & Technol Sch Environm Sci & Spatial Informat Xuzhou 221116 Jiangsu Peoples R China

Six-DoF (Six-degree-of-freedom) pose localization based on 3D point clouds is a challenging task for LBSs (localization-based services). This paper proposes a robust and efficient method that uses multimodal information (vision and Wi-Fi signal information) to estimate the 6-DoF pose of an RGBD camera on a robot with respect to complex 3D textured models of the indoor environment that can contain more than 650,000,000 points. Our developed method narrows the search scope, which delimits boundaries initially using the Wi-Fi location system and applies an environment-adaptive approach to determine the radius of the search sphere based on the signal stability of the Wi-Fi location system. In addition, we propose an algorithm for estimating a novel correspondence between local points with a 3D submap by combining 3D points and surface normals to acquire absolute poses from noisy and outlier-contaminated matching point sets for RGBD sensors in dynamic indoor scenes. Then, a novel two-level spatial verification strategy is used to estimate an accurate pose, which includes the use of a RANSAC (Random Sample Consensus) algorithm for identification and a direct least-square method to acquire the pose from the inliers. The proposed method has been implemented and tested extensively in various indoor scenes. The experimental results demonstrate that the Wi-Fi-aided localization system can efficiently localize a mobile robot in a variety of large-scale 3D point cloud datasets to realize stable time consumption and similar performance to state-of-the-art methods.

关键词： Location awareness Three-dimensional displays Robots Wireless fidelity Visualization Fingerprint recognition Indoor environment Visual localization Wi-Fi positioning 6-DoF pose multimodal information computation complexity

来源：评论

学校读者我要写书评

暂无评论

Two-Dimensional Eulerian-Exponential-Law Acoustic Black Hole Structure for Energy Harvesting

引用

IEEE SENSORS JOURNAL 2023年第11期23卷 11762-11773页

作者： Qin, Yi Han, Gangxia Mao, Yongfang Chongqing Univ State Key Lab Mech Transmiss Coll Mech Engn Chongqing 400044 Peoples R China Chongqing Univ Coll Automat Chongqing 400044 Peoples R China

Thin plates are widely used in engineering, so it is of great value to explore energy harvester based on this type of structure. Acoustic black hole (ABH) is helpful for the energy harvesting of thin plate. However, the traditional power-law ABH needs to be improved in the low-frequency energy harvesting. Thereupon, a new Eulerian exponential law for ABH is proposed, and a 2-D ABH structure based on the Eulerian exponential law is designed for harvesting low-frequency energy. This article constructs a simple electromechanical coupling dynamic model for the Eulerian-exponential-law ABH energy harvester (EAEH). This model has low computation complexity as the dimension of thin plate is reduced by the Kronecker product of x- and y-direction beams' modes. Combining the element division and modal analysis of beam, a new method with high computational efficiency is proposed for calculating the base functions of thin plate with 2-D ABH, and its effectiveness and accuracy are validated by the result of finite-element analysis. Under different excitation frequencies, the voltage and power responses of EAEH are simulated, and their validity is verified by the experimental results. Moreover, EAEH is compared with the power-law ABH energy harvester through the simulation and experiment. The comparative results show that EAEH has lower resonant frequencies and higher output of voltage and power.

关键词： Acoustic black hole (ABH) computation complexity electromechanical coupling energy harvester low frequency

来源：评论

学校读者我要写书评

暂无评论

Tableau Systems for Deontic Action Logics Based on Finite Boolean Algebras, and Their complexity

引用

STUDIA LOGICA 2017年第2期105卷 229-251页

作者： Castro, Pablo F. Univ Nacl Rio Cuarto Dept Computac Ruta 36 Km 601 Rio Cuarto Argentina

We introduce a family of tableau calculi for deontic action logics based on finite boolean algebras (or DAL for short), these logics provide deontic operators (e.g., obligation, permission, prohibition) which are applied to a finite number of actions (the vocabulary of the logic);furthermore, in these formalisms, actions can be combined by means of boolean operators, this provides an expressive algebra of actions. We define a tableau calculus for the basic logic and then we extend this calculus to cope with extant variations of this formalism;we prove the soundness and completeness of these proof systems. In addition, we investigate the computational complexity of the satisfiability problem for DAL and its extensions;we show this problem is NP-complete when the number of actions considered is fixed, and it is -Hard (in Stockmeyer's polynomial hierarchy) when the number of actions is taken as an extra parameter. The tableau systems introduced here can be implemented in PSPACE, this seems reasonable taking into consideration the computational complexity of the logics.

关键词： Deontic action logics Tableau systems computation complexity SAT

来源：评论

学校读者我要写书评

暂无评论

On the solution to QBD processes with finite state space

引用

STOCHASTIC ANALYSIS AND APPLICATIONS 2007年第4期25卷 763-779页

作者： Elhafsi, Essia H. Molle, Mart Univ Calif Riverside Dept Comp Sci & Engn Riverside CA 92521 USA

In this article, we present a solution to a class of Quasi-Birth-and-Death processes with finite state space and show that the stationary probability vector has a matrix geometric representation. We show that such models have a level-dependent rate matrix. The corresponding rate matrix is given explicitly in terms of the model parameters. The resulting closed-form expression is proposed as a basis for efficient calculation of the stationary probabilities. The method proposed in this article can be applied to several queueing systems.

关键词： closed-form solution computation complexity Markov chain matrix geometric

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：