检索结果-内蒙古大学图书馆

Constrained Markov decision processes with uncertain costs

OPERATIONS RESEARCH LETTERS 2022年第2期50卷 218-223页

作者： Varagapriya, V. Singh, Vikas Vikram Lisser, Abdel Indian Inst Technol Delhi Dept Math New Delhi 110016 India Univ Paris Saclay CNRS Cent Supelec Lab Signaux & Syst F-91190 Gif Sur Yvette France

We consider a finite state-action discounted constrained Markov decision process with uncertain running costs and known transition probabilities. We propose equivalent linear programming, second-order cone programming and semidefinite programming problems for the robust constrained Markov decision processes when the uncertain running cost vectors belong to polytopic, ellipsoidal, and semidefinite cone uncertainty sets, respectively. As an application, we study a variant of a machine replacement problem and perform numerical experiments on randomly generated instances of various sizes. (C) 2022 Elsevier B.V. All rights reserved.

关键词： Constrained Markov decision processes Uncertainty sets Linear programming problem Second-order cone programming problem semidefinite programming problem Machine replacement problem

来源：评论

学校读者我要写书评

暂无评论

Computing controlled invariant sets for hybrid systems with applications to model-predictive control

引用

IFAC-PapersOnLine 2018年第16期51卷 193-198页

作者： Legat, Benoît Tabuada, Paulo Jungers, Raphaël M. ICTEAM Université catholique de Louvain 4 Av. G. Lemaître Louvain-la-Neuve1348 Belgium Department of Electrical and Computer Engineering UCLA United States

In this paper, we develop a method for computing controlled invariant sets using semidefinite programming. We apply our method to the controller design problem for switching affine systems with polytopic safe sets. The task is reduced to a semidefinite programming problem by enforcing an invariance relation in the dual space of the geometric problem. The paper ends with an application to safety critical model predictive control. © 2018

关键词： Controllers Hybrid systems Model predictive control Safety engineering Scalability Controller designs Controller synthesis Invariance relation LMIs Scalable methods Semi definite programming semidefinite programming problem Set invariance

来源：评论

学校读者我要写书评

暂无评论

Low-complexity precoding for MIMO channels with finite alphabet input

引用

ELECTRONICS LETTERS 2017年第3期53卷 160-162页

作者： Cao, Kuo Wu, Yongpeng Yang, Weiwei Cai, Yueming Cao, Kuo PLA Univ Sci & Technol Coll Commun Engn Nanjing 210007 Jiangsu Peoples R China Univ Erlangen Nurnberg Inst Digital Commun D-91058 Erlangen Germany

Low-complexity precoding design without iteration for multiple-input multiple-output channels with finite alphabet input is studied. Contrast to the iterative gradient method for finding the globally optimal precoder, which is time-consuming and computationally complicated, this work studies low-complexity precoding design with high performance. The problem of optimising the mutual information is identical to maximising the minimum Euclidean distance of the input vector at high total power. Hence, the precoding design can be formulated as semi-definite programming problem and thus can be optimally solved. Numerical examples show that the proposed scheme achieves good tradeoff between the computational complexity and high performance compared with the conventional counterparts.

关键词： MIMO communication wireless channels iterative methods gradient methods mathematical programming precoding MIMO channels finite alphabet input low complexity precoding design multiple-input multiple-output channels iterative gradient method globally optimal precoder mutual information minimum Euclidean distance input vector semidefinite programming problem computational complexity

来源：评论

学校读者我要写书评

暂无评论

Beamforming strategies for multi-antenna relay-assisted networks

引用

IET COMMUNICATIONS 2016年第11期10卷 1384-1393页

作者： Mirzaee, Meysam Akhlaghi, Soroush Shahed Univ Dept Elect Engn Tehran Iran

Physical layer security has received considerable attentions in recent years. Moreover, cooperative communications using some nodes of network as relays make use of the benefit of multi-antenna systems such as increasing the secrecy capacity. This study studies a communication network incorporating some multi-input-multi-output amplify and forward relays in the presence of some eavesdroppers. The objective persuaded in the current work is to find the beamforming matrices at the relays to maximise the achievable secrecy rate under either individual or total power constraint at these nodes. Accordingly, three main approaches including general rank beamforming (GRBF), rank-1 beamforming (RBF) and null-space beamforming (NSBF) are developed. For the NSBF under the total power constraint, a closed-form solution is obtained, while for the remaining scenarios the corresponding optimisation problem is expressed as a semi-definite programming problem. Numerical results indicate that the RBF and NSBF methods follow GRBF in some cases and degraded from GRBF in the others. However, it is shown that these two methods have much lower complexity than GRBF.

关键词： array signal processing antenna arrays relay networks (telecommunication) telecommunication security cooperative communication MIMO communication amplify and forward communication matrix algebra mathematical programming semidefinite programming problem optimisation problem closed-form solution NSBF null-space beamforming RBF rank-1 beamforming GRBF general rank beamforming total power constraint achievable secrecy rate maximisation beamforming matrix multiinput multioutput amplify and forward relays cooperative communication physical layer security multiantenna relay-assisted network

来源：评论

学校读者我要写书评

暂无评论

Achievable secrecy rate of wiretap channels incorporating multi-input-multi-output amplify and forward relaying

引用

IET COMMUNICATIONS 2016年第3期10卷 300-308页

作者： Mirzaee, Meysam Akhlaghi, Soroush Shahed Univ Dept Engn Inst Modern Informat & Commun Technol Tehran Iran

This study discusses the secrecy rate of two-hop relay-assisted cooperative wiretap channels, incorporating multi-antenna amplify and forward relaying in the middle of transmission. In this regard, under the Gaussian code book assumption, three main scenarios including null-space beamforming (NSBF), rank-1 beamforming (RBF), and the so-called general rank beamforming (GRBF) are proposed to be employed at the relay where their achievable secrecy rates are studied. Accordingly, for NSBF, a closed-form solution is derived, whereas the corresponding optimisation problems are formulated for the remaining cases as a standard semi-definite programming problem. Though GRBF ranks the first in terms of the achievable secrecy rate, RBF exhibits favourable results with a much lower complexity, as the corresponding optimisation problem runs over a reduced dimension. Moreover, NSBF has a much lower complexity, as it provides an analytical solution at the expense of a decrease in the secrecy rate, and interestingly, it performs quite well when the number of eavesdroppers is less than that of the relay antennas.

关键词： relay networks (telecommunication) MIMO communication amplify and forward communication telecommunication security array signal processing antenna arrays cooperative communication Gaussian processes codes mathematical programming multiinput-multioutput amplify and forward relaying two-hop relay cooperative wiretap channels multiantenna amplify and forward relaying Gaussian code book assumption null-space beamforming NSBF rank-1 beamforming general rank beamforming GRBF semidefinite programming problem relay antennas

来源：评论

学校读者我要写书评

暂无评论

Beamforming with opportunistic relaying for wireless security

引用

IET COMMUNICATIONS 2014年第8期8卷 1198-1210页

作者： Sarkar, Mohammad Zahurul Islam Ratnarajah, Tharmalingam Ding, Zhiguo Univ Edinburgh Sch Engn Inst Digital Commun Edinburgh EH9 3JL Midlothian Scotland Newcastle Univ Sch Elect Elect & Comp Engn Newcastle Upon Tyne NE1 7RU Tyne & Wear England

The authors present a beamforming scheme with opportunistic relaying (namely opportunistic beamforming) for wireless security under amplify-and-forward (AF) and decode-and-forward (DF) strategies. The relay selection is performed using the method of distributed timers, where all the relays use their timers to estimate own instantaneous channel gains and compete to access the wireless medium according to their own channel conditions. The performance of opportunistic beamforming scheme in terms of secure outage probability is analysed and the beamforming problem as a semidefinite programming problem with its optimisation framework is formulated. The results show that, in an opportunistic beamforming scheme, competition among cooperative relays offers diversity benefits in the direction of destination that enhances secrecy rate (i.e. minimises secure outage probability) and adhere to the opportunistic' cooperation rule giving priority to the best' available relay even when they are not chosen to transmit but rather chosen to cooperatively listen. Opportunistic beamforming scheme with DF strategy enhances secrecy rate than the beamforming with multiple DF relays while in the case of AF strategy, it provides significant improvement in the secrecy rate compared to the opportunistic relaying, the equal-power multiple-relay transmission and the single-relay transmission schemes.

关键词： cooperative communication relay networks (telecommunication) amplify and forward communication decode and forward communication probability mathematical programming array signal processing opportunistic relaying wireless security opportunistic beamforming scheme amplify-and-forward strategy decode-and-forward strategy DF strategy AF strategy secure outage probability semidefinite programming problem optimisation framework cooperative relays single-relay transmission schemes equal-power multiple-relay transmission

来源：评论

学校读者我要写书评

暂无评论

Force sensorless bilateral control using a dynamical asymmetric compensator

Force sensorless bilateral control using a dynamical asymmet...

引用

International Power Electronics Conference (IPEC-ECCE-ASIA)

作者： Hama, Ryota Imai, Jun Takahashi, Akiko Funabiki, Shigeyuki Okayama Univ Dept Elect & Elect Engn Okayama 7008530 Japan

ISBN: (纸本)9781479927050

Among other bilateral control systems, those of symmetric type have advantage of simple structure, force sensorless and readiness to stabilize. However, a symmetric type bilateral system is known to have poor haptic performance. In this paper, we propose a bilateral system design without force sensor, based on a generalized system structure of master slave systems. Force feedback and position tracking performance are taken into account by H2 performance at frequency range of the desired haptic transfer, and influence of the measurement noise is suppressed by H-infinity condition. Such a multi-objective controller is designed by solving a semidefinite programming problem. The derived controller tends to have large condition number;we truncate balanced realization of the controller to obtain feasible feedback systems. Effectiveness of the proposed approach is illustrated by numerical studies in time as well as frequency domains, and also experiments.

关键词： Bilateral control Force sensorless asymmetrric compensator semidefinite programming problem

来源：评论

学校读者我要写书评

暂无评论

A Primal Interior Point Method for the Linear semidefinite programming problem

引用

COMPUTATIONAL MATHEMATICS AND MATHEMATICAL PHYSICS 2008年第10期48卷 1746-1767页

作者： Babynin, M. S. Zhadan, V. G. IV Kurchatov Atom Energy Inst Moscow 123182 Russia

The linear semidefinite programming problem is examined. A primal interior point method is proposed to solve this problem. It extends the barrier-projection method used for linear programs. The basic properties of the... 详细信息

关键词： semidefinite programming problem primal method interior point method local convergence

来源：评论

学校读者我要写书评

暂无评论

Force sensorless bilateral control using a dynamical asymmetric compensator

Force sensorless bilateral control using a dynamical asymmet...

引用

International Power Electronics Conference

作者： Ryota Hama Jun Imai Akiko Takahashi Shigeyuki Funabiki Department of Electrical and Electronic Engineering Okayama University

ISBN: (纸本)9781479927067

关键词： Bilateral control Force sensorless Asymmetrric compensator semidefinite programming problem

来源：评论

学校读者我要写书评

暂无评论

Robust set-membership filtering for systems with missing measurement: a linear matrix inequality approach

引用

IET SIGNAL PROCESSING 2012年第4期6卷 341-347页

作者： Yang, F. Li, Y. E China Univ Sci & Technol Sch Informat Sci & Engn Shanghai 200237 Peoples R China Cent Queensland Univ Ctr Intelligent & Networked Syst Rockhampton Qld 4702 Australia Brunel Univ Dept Informat Syst & Comp Uxbridge UB8 3PH Middx England

This study addresses the robust set-membership finite-horizon filtering problem for a class of discrete time-varying systems with missing measurement and polytopic uncertainties in the presence of unknown-but-bounded process and measurement noises. A robust set-membership filter is developed and a recursive algorithm is derived for computing the state estimate ellipsoid that is guaranteed to contain the true state. An optimal possible estimate set is computed recursively by solving the semi-definite programming problem. Simulation results are provided to demonstrate the effectiveness of the proposed method.

关键词： measurement noises linear matrix inequality approach recursive estimation Optimisation techniques state estimation missing measurement robust set-membership filtering Algebra uncertain systems state estimate ellipsoid mathematical programming optimal possible estimate set Filtering methods in signal processing linear matrix inequalities discrete time-varying systems semidefinite programming problem polytopic uncertainty robust set-membership finite-horizon filtering problem Signal processing theory discrete time systems time-varying systems recursive algorithm filtering theory unknown-but-bounded process Other topics in statistics

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

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

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：