检索结果-内蒙古大学图书馆

arXiv 2017年

作者： Wang, Jin Shu, Feng Lu, Jinhui Yu, Hai Chen, Riqing Li, Jun Jayakody, Dushantha Nalin K. School of Electronic and Optical Engineering Nanjing University of Science and Technology 210094 China College of Computer and Information Sciences Fujian Agriculture and Forestry University Fuzhou350002 China China Research Institute of Radiowave Propagation National Key Laboratory of Electromagnetic Environment Qingdao266107 China National Research Tomsk Polytechnic University Department of Control System Optimization Institute of Cybernetics Russia

In this paper, we make an investigation on the summean-square-error (sum-MSE) performance gain achieved by DFT-based least-square (LS) channel estimator over frequencydomain LS one in full-duplex OFDM system in the presence of colored interference and noise. The closed-form expression of the sum-MSE performance gain is given. Its simple upper and lower bounds are derived by using inequalities of matrix eigen-values. By simulation and analysis, the upper lower bound is shown to be close to the exact value of MSE gain as the ratio of the number N of total subcarriers to the cyclic prefix length L grows and the correlation factor of colored interference increases. More importantly, we also find that the MSE gain varies from one to N/L as the correlation among colored interferences decreases gradually. According to theoretical analysis, we also find the MSE gain has very simple forms in two extreme scenarios. In the first extreme case that the colored interferences over all subchannels are fully correlated, i.e., their covariance matrix is a matrix of allones, the sum-MSE gain reduces to 1. In other words, there is no performance gain. In the second extreme case that the coloredinterference covariance matrix is an identity matrix, i.e, they are mutually independent, the achievable sum-MSE performance gain is N/L. A large ratio N/L will achieve a significant sum-MSE gain. Copyright © 2017, The Authors. All rights reserved.

关键词： Covariance matrix

来源：评论

学校读者我要写书评

暂无评论

Exploiting Active RIS in NOMA Networks with Hardware Impairments

arXiv

引用

arXiv 2023年

作者： Yue, Xinwei Song, Meiqi Ouyang, Chongjun Liu, Yuanwei Li, Tian Hou, Tianwei The Key Laboratory of Information and Communication Systems Ministry of Information Industry China The Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100101 China The School of Electrical and Electronic Engineering University College Dublin DublinD04 V1W8 Ireland The School of Electronic Engineering and Computer Science Queen Mary University of London LondonE1 4NS United Kingdom The 54th Research Institute of China Electronics Technology Group Corporation Hebei Shijiazhuang050081 China The School of Electronic and Information Engineering Beijing Jiaotong University Beijing100044 China Erlangen91054 Germany

Active reconfigurable intelligent surface (ARIS) is a promising way to compensate for multiplicative fading attenuation by amplifying and reflecting event signals to selected users. This paper investigates the performance of ARIS assisted non-orthogonal multiple access (NOMA) networks over cascaded Nakagami-m fading channels. The effects of hardware impairments (HIS) and reflection coefficients on ARIS-NOMA networks with imperfect successive interference cancellation (ipSIC) and perfect successive interference cancellation (pSIC) are considered. More specifically, we develop new precise and asymptotic expressions of outage probability and ergodic data rate with ipSIC/pSIC for ARIS-NOMA-HIS networks. According to the approximated analyses, the diversity orders and multiplexing gains for couple of non-orthogonal users are attained in detail. Additionally, the energy efficiency of ARIS-NOMA-HIS networks is surveyed in delay-limited and delay-tolerant transmission schemes. The simulation findings are presented to demonstrate that: i) The outage behaviors and ergodic data rates of ARIS-NOMA-HIS networks precede that of ARIS aided orthogonal multiple access (OMA) and passive reconfigurable intelligent surface (PRIS) aided OMA;ii) As the reflection coefficient of ARIS increases, ARIS-NOMA-HIS networks have the ability to provide the strengthened outage performance;and iii) ARIS-NOMA-HIS networks are more energy efficient than ARIS/PRIS-OMA networks and conventional cooperative schemes. Copyright © 2023, The Authors. All rights reserved.

关键词： Energy efficiency

来源：评论

学校读者我要写书评

暂无评论

Age-Based Utility Maximization for Wireless Powered Networks: A Stackelberg Game Approach

Age-Based Utility Maximization for Wireless Powered Networks...

引用

IEEE Global Communications Conference

作者： Haina Zheng Ke Xiong Pingyi Fan Zhangdui Zhong Khaled Ben Letaief School of Computer and Information Technology Beijing Jiaotong University Beijing China Beijing Key Laboratory of Traffic Data Analysis and Mining Beijing Jiaotong University Beijing China Department of Electronic Engineering Tsinghua University Beijing China State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China The Hong Kong University of Science and Technology Hong Kong

ISBN: (数字)9781728109626

ISBN: (纸本)9781728109633

This paper investigates the efficient cooperation in wireless-powered communication networks, where an access point (AP) and multiple helpers first together charge up a sensor via radio-frequency (RF)-based wireless power transfer (WPT), and then the sensor uses the harvested energy to transmit real-time status updates to the AP. Due to the selfishness of the helpers, payment is provided as an incentive to them by the sensor-AP communication pair. For such a system, a Stackelberg game approach is designed to establish efficient cooperation between the helpers and the sensor-AP communication pair. An Age of Information (AoI)-based utility and a profit-based utility are defined for the sensor-AP pair and the helpers, respectively. Optimization problems are formulated to maximize their utilities. An explicit expression of the optimal transmit power of the helper is derived, with which a Dinkelbach's Programming (DP)-based algorithm is designed to jointly find the optimal payment price and transmit power at the AP, and at the same time, the Stackelberg equilibrium (SE) is achieved. Moreover, a closed-form expression of the minimum AoI of the system is also presented. Numerical results show that the more helpers there exist, the higher payment price the AP should fix, and meanwhile, the lower AoI of the sensor-AP communication pair can be achieved. Besides, it is shown that by increasing the transmit power at the AP, the optimal average AoI could not be reduced evidently.

关键词： Games Real-time systems Energy harvesting Wireless communication Measurement Batteries Wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

Observation of nonreciprocal magneto-optical scattering in nonencapsulated few-layered CrI3

arXiv

引用

arXiv 2020年

作者： Guo, Kai Liu, Zhen Hu, Guangwei Shi, Zhongtai Li, Yue Zhang, Linbo Chen, Haiyan Zhang, Li Zhou, Peiheng Lu, Haipeng Lin, Miao-Ling Liu, Sizhao Cheng, Yingchun Liu, Xue Lu Xie, Jianliang Bi, Lei Tan, Ping-Heng Deng, Long jiang Qiu, Cheng-Wei Peng, Bo National Engineering Research Center of Electromagnetic Radiation Control Materials School of Electronic Science and Engineering University of Electronic Science and Technology of China Chengdu611731 China Department of Electrical and Computer Engineering National University of Singapore 117583 Singapore Key Laboratory of Flexible Electronics Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced Materials Nanjing Tech University Nanjing211816 China State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences P. O. Box 912 Beijing100083 China

"Magneto-optical" effect refers to a rotation of polarization plane, which has been widely studied in traditional ferromagnetic metal and insulator films and scarcely in two-dimensional layered materials. Here we uncover a new nonreciprocal magneto-inelastic light scattering effect in ferromagnetic few-layer CrI3. We observed a rotation of the polarization plane of inelastic light scattering between -20o and +60o that are tunable by an out-of-plane magnetic field from -2.5 to 2.5 T. It is experimentally observed that the degree of polarization can be magnetically manipulated between -20% and 85%. This work raises a new magneto-optical phenomenon and could create opportunities of applying 2D ferromagnetic materials in Raman lasing, topological photonics, and magneto-optical modulator for information transport and storage. © 2020, CC BY-NC-SA.

关键词： Ferromagnetic materials

来源：评论

学校读者我要写书评

暂无评论

QoS-aware User Association and Transmission Scheduling for Millimeter-Wave Train-ground Communications

arXiv

引用

arXiv 2023年

作者： Zhang, Xiangfei Niu, Yong Yang, Tao Xiao, Xian Ding, Jianwen Chen, Sheng Zhong, Zhangdui Wang, Ning Ai, Bo State Key Laboratory of Rail Traffic Control and Safety China Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong University Beijing100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China National Mobile Communications Research Laboratory Southeast University Nanjing211189 China School of Electronics and Computer Science University of Southampton SouthamptonSO17 1BJ United Kingdom Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing Jiaotong University Beijing100044 China School of Information Engineering Zhengzhou University Zhengzhou450001 China

With the development of wireless communication, people have put forward higher requirements for train-ground communications in the high-speed railway (HSR) scenarios. With the help of mobile relays (MRs) installed on the roof of the train, the application of Millimeter-Wave (mm-wave) communication which has rich spectrum resources to the train-ground communication system can realize high data rate, so as to meet users’ increasing demand for broad-band multimedia access. Also, full-duplex (FD) technology can theoretically double the spectral efficiency. In this paper, we formulate the user association and transmission scheduling problem in the mm-wave train-ground communication system with MR operating in the FD mode as a nonlinear programming problem. In order to maximize the system throughput and the number of users meeting quality of service (QoS) requirements, we propose an algorithm based on coalition game to solve the challenging NP-hard problem, and also prove the convergence and Nash-stable structure of the proposed algorithm. Extensive simulation results demonstrate that the proposed coalition game based algorithm can effectively improve the system throughput and meet the QoS requirements of as many users as possible, so that the communication system has a certain QoS awareness. Copyright © 2023, The Authors. All rights reserved.

关键词： Game theory

来源：评论

学校读者我要写书评

暂无评论

Analysis of simulation risk and VV and a based on extended FMECA

引用

Xitong Fangzhen Xuebao / Journal of System Simulation 2008年第15期20卷 3934-3939页

作者： Zheng, Li-Ping Liu, Xiao-Ping School of Computer Science and Information Hefei University of Technology Hefei 230009 China Engineering Research Center of Safety Critical Industry Measure and Control Technology Min. of Edu. Hefei University of Technology Hefei 230009 China

VV and A is risk-driven activity, and FMECA is a widely used risk analysis method. Based on them, a new method, aiming to M and S (Modeling and Simulation) domain and named SimFMECA, was put forward. Firstly, FMECA analysis table and process was extended, then a framework of FMI to general simulation system was discussed, moreover, a risk and criticality ranking measure was proposed, and according to the risk rank, required VV and A effort was identified, including VV and A level and VV and A activities. Finally an experiment was carried out to validate SimFMECA. SimFMECA is a qualitative method, and is characteristic of low cost and easy implementation.

关键词： Credibility FMECA Level Modeling and simulation (M and S) Risk VV and A

来源：评论

学校读者我要写书评

暂无评论

Experimental quantum key distribution with source flaws

引用

Physical Review A 2015年第3期92卷 032305-032305页

作者： Feihu Xu Kejin Wei Shihan Sajeed Sarah Kaiser Shihai Sun Zhiyuan Tang Li Qian Vadim Makarov Hoi-Kwong Lo Centre for Quantum Information and Quantum Control (CQIQC) Department of Electrical & Computer Engineering and Department of Physics University of Toronto Toronto Ontario M5S 3G4 Canada School of Science and State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China Institute for Quantum Computing (IQC) University of Waterloo Waterloo Ontario N2L 3G1 Canada Department of Electrical and Computer Engineering University of Waterloo Waterloo Ontario N2L 3G1 Canada Department of Physics and Astronomy University of Waterloo Waterloo Ontario N2L 3G1 Canada College of Science National University of Defense Technology Changsha 410073 China

Decoy-state quantum key distribution (QKD) is a standard technique in current quantum cryptographic implementations. Unfortunately, existing experiments have two important drawbacks: the state preparation is assumed to be perfect without errors and the employed security proofs do not fully consider the finite-key effects for general attacks. These two drawbacks mean that existing experiments are not guaranteed to be proven to be secure in practice. Here, we perform an experiment that shows secure QKD with imperfect state preparations over long distances and achieves rigorous finite-key security bounds for decoy-state QKD against coherent attacks in the universally composable framework. We quantify the source flaws experimentally and demonstrate a QKD implementation that is tolerant to channel loss despite the source flaws. Our implementation considers more real-world problems than most previous experiments, and our theory can be applied to general discrete-variable QKD systems. These features constitute a step towards secure QKD with imperfect devices.

关键词： Quantum states Quantum theory Quantum entanglement Quantum cryptography Quantum computing

来源：评论

学校读者我要写书评

暂无评论

Biodegradation of Benzo[A]Pyrene By a Marine Chlorella Vulgaris Lh-1 with Heterotrophic Ability

SSRN

引用

SSRN 2023年

作者： Chen, Qingguo Li, Zhenzhen Li, Yijing Liu, Mei Wu, Yingqi Chen, Zhi Zhu, Baikang Zhejiang Provincial Key Laboratory of Petrochemical Pollution Control Zhejiang Ocean University Zhoushan China National & local Joint Engineering Research Center of Harbor Oil & Gas Storage and Transportation Technology Zhejiang Ocean University Zhoushan316022 China School of Marine Science & Technology Zhejiang Ocean University Zhoushan China Department of Building Civil and Environmental Engineering Faculty of Engineering & Computer Sciences Concordia University MontrealQCH3G1M8 Canada

In this study, a microalga, Chlorella vulgaris LH-1, with heterotrophic ability to degrade benzo[a]pyrene (BaP) was explored. The effect of BaP concentration on microalga growth was investigated, and the possible biodegradation mechanism of BaP was proposed. Results showed that 5 mg/L had a significant inhibitory effect on its growth. During heterotrophic cultivation, 20 mg/L BaP inhibited its growth significantly. The expression of functional enzyme genes of LH-1 such as phenol 2-monooxygenase activity, protocatechuate 3,4-dioxygenase activity, catechol 1,2-dioxygenase activity, styrene degradation, and benzoate degradation were upregulated in the process of BaP degradation. The degradation of BaP by this microalga under mixotrophic condition goes through the degradation pathway of phthalic acid, whereas it goes through the degradation pathway of benzoic acid under heterotrophic condition. © 2023, The Authors. All rights reserved.

关键词： Biodegradation

来源：评论

学校读者我要写书评

暂无评论

Guarding Force: Safety-Critical Compliant control for Robot-Environment Interaction

arXiv

引用

arXiv 2024年

作者： Wang, Xinming Yang, Jun Mao, Jianliang Liang, Jinzhuo Li, Shihua Yan, Yunda The Key Laboratory of Measurement and Control of CSE Ministry of Education School of Automation Southeast University Nanjing210096 China The Department of Aeronautical and Automotive Engineering Loughborough University LoughboroughLE11 3TU United Kingdom The College of Automation Engineering Shanghai University of Electric Power Shanghai201306 China The Department of Computer Science University College London LondonWC1E 6BT United Kingdom

In this study, we propose a safety-critical compliant control strategy designed to strictly enforce interaction force constraints during the physical interaction of robots with unknown environments. The interaction force constraint is interpreted as a new force-constrained control barrier function (FC-CBF) by exploiting the generalized contact model and the prior information of the environment, i.e., the prior stiffness and rest position, for robot kinematics. The difference between the real environment and the generalized contact model is approximated by constructing a tracking differentiator, and its estimation error is quantified based on Lyapunov theory. By interpreting strict interaction safety specification as a dynamic constraint, restricting the desired joint angular rates in kinematics, the proposed approach modifies nominal compliant controllers using quadratic programming, ensuring adherence to interaction force constraints in unknown environments. The strict force constraint and the stability of the closed-loop system are rigorously analyzed. Experimental tests using a UR3e industrial robot with different environments verify the effectiveness of the proposed method in achieving the force constraints in unknown environments. Note to Practitioners—Robotic manipulators are increasingly involved in complex interaction missions with humans and various environments. As these interactions become more prevalent, ensuring the safety of both robots and their human and environmental counterparts has become imperative. Although advanced controllers with safety constraints have been explored, ensuring strict interaction force guarantees remains challenging, particularly in unknown environments. To address this challenge, this paper proposes a new safety-critical compliant control scheme using the control barrier function (CBF) technique. By formulating the approach as quadratic programming and dynamically adjusting the nominal compliant controller online, the propose

关键词： controllers

来源：评论

学校读者我要写书评

暂无评论

Study on mechanisms of secure data aggregation based on weighted fitting analysis

引用

Ruan Jian Xue Bao/Journal of Software 2013年第SUPPL.1期24卷 108-116页

作者： Li, Ping Yang, Wu Xie, Jin-Yang Zhu, Hong-Song Zhang, Yong-Guang Li, Xiao-Feng School of Computer and Telecommunications Changsha University of Science and Technology Changsha 410114 China State Key Laboratory of Information Security Institute of Information Engineering The Chinese Academy of Sciences Beijing 100093 China Software Development Center Beijing Institute of Control Engineering Beijing 100190 China

Cryptographic approaches are vulnerable to impersonation attacks when nodes become compromised. Meanwhile, trust-based judgment and confirmation of cluster heads in WSN imposes higher communication cost. Trust management and authentication on cluster heads in WSN are essential in research on the mechanisms of secure data aggregation at present. In this paper, an energy attenuation model is adopted to describe event sensing in a kind of WSNs. Approximate evaluation on distance between occurring event and nodes within a cluster is achieved in case the location of the event is not known. Distribution properties of data points with clustering characteristics based on fitting curve construction are theoretically analyzed. In addition, the mechanism on trust authentication on cluster heads is also refined. Experimental results show that the proposed mechanism has much better performance on fitting accuracy and malicious CH recognition than previous works. © 2013 ISCAS.

关键词： Authentication

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：