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5th International Conference on Geographical Information systems Theory, Applications and Management (GISTAM)

作者： Ghorbanzadeh, Omid Blaschke, Thomas Univ Salzburg Dept Geoinformat Z GIS Salzburg Austria

ISBN: (纸本)9789897583711

Remarkable improvement has been made in object detection and image classification, mainly due to the availability of large-scale labelled data and also the progress of deep convolutional neural networks (CNNs). Thus, this amount of training data enables CNNs to learn data-driven image features. However, generating the efficient sample patches from the satellite images for training the CNNs remains a challenge. In this study, we use a CNN for the case of landslide detection based on the optical data from the Rapid Eye satellite. We separate the image into training and test areas of the highly landslide-prone Rasuwa district in Nepal. Thus, the sample patches were extracted from the training area of the Rapid Eye image. Although the approach of random sample patches is considered as the most common for feeding the CNNs, it is not the best solution for all object detection aims. We feed our structured CNN with the randomly selected sample patches as our first approach. For the second approach, the same CNN architecture is trained by the patches that selected based on only the central areas of any landslide. The trained CNNs based on both approaches were used to detection the landslides in an area where considered as our test zone. The detection results are compared against a precise inventory dataset of landslide polygons through a mean intersection-over-union (mIOU). The mIOU value of the first approach is 53.56%. However, that of the second one is 56.24%, which shows an approximately 3% improvement in the resulting accuracy of the landslide detection using the sample patches generated by the second approach. Rather, the current performance of CNNs in object detection domain they strongly depend on the quality of the training data and augmentation strategies.

关键词： Convolutional Neural network RapidEye mean Intersection Over Union Training Data Set

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攻击与故障共存的ICPS综合安全控制与通讯协同设计

攻击与故障共存的ICPS综合安全控制与通讯协同设计

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作者：张建军兰州理工大学

学位级别：硕士

信息物理融合系统(Cyber-Physical System,CPS)是集感知、计算、控制及网络通讯于一体的新一代智能系统,因其具有结构网络化、功能模块化、控制智能化等优点,已广泛应用至各行各业,其中CPS与工业控制融合而产生的工业信息物理融合系统(I... 详细信息

信息物理融合系统(Cyber-Physical System,CPS)是集感知、计算、控制及网络通讯于一体的新一代智能系统,因其具有结构网络化、功能模块化、控制智能化等优点,已广泛应用至各行各业,其中CPS与工业控制融合而产生的工业信息物理融合系统(Industry Cyber-Physical System,ICPS),已成为当今工业控制系统的首选架构。然而,ICPS在其发展过程中也面临众多亟待解决的难题,诸如:随着工业网络从相对封闭变得更为开放,网络安全问题变得尤为突出;与传统的工业控制系统相比,虽ICPS网络化、数字化、智能化水平更高,但其工作环境依然较为恶劣,其物理器件的故障问题也不容忽视;此外,ICPS强大的数据感知能力致使终端设备需经网络传输更多的数据,与有限网络资源间的矛盾也日益突出,等等。然而,目前能有效解决上述问题的方法还很有限,为此,本文聚焦于上述问题中时空隐蔽性强且危害大的假数据注入(False Data Inj ection,FDI)攻击和位处恶劣环境的执行器发生的故障,在离散事件触发机制(Discrete Event-Triggered communication Scheme,DETCS)下,对ICPS开展了如下综合安全控制研究:1)针对FDI攻击与执行器故障共存的ICPS,首先,通过综合考虑计算、通讯资源的合理分配与高效利用,以及便于攻击防御策略实施等因素,在DETCS下,构建了 ICPS综合安全控制框架;其次,设计了鲁棒H∞估计器,实现了系统状态、执行器故障及双侧网络FDI攻击的准确估计;接着,基于所得估计结果,设计了对双侧网络FDI攻击采用分离与补偿、对执行器故障采用补偿的综合安全控制策略,同时结合事件触发条件,给出了综合安全控制与通讯的协同设计方法;最后,通过数值算例及四容水箱实例,仿真验证了所提方法的有效性。2)考虑到实际工业控制中,在确保ICPS安全且抗扰的同时,还期望具有更好的动态性能,进一步研究了多目标约束下ICPS综合安全控制与通讯协同设计问题。通过引入α-稳定的概念,分别给出了具有α1-稳定的鲁棒H∞估计器,以及具有α2-稳定的综合安全控制与通讯协同设计方法。在定理推证中,考虑到参数设定法在处理非线性矩阵不等式(Nonlinear Matrix Inequality,NLMI)时的保守性和多目标约束下解空间的缩减问题,采用了具有更少保守性的锥补线性化(Cone Complementary Linearization,CCL)算法,从而增大了解空间、提高了 ICPS控制性能。仿真结果表明,多目标约束与CCL算法结合下设计的鲁棒H∞估计器、综合安全控制器,使得ICPS在安全运行的同时,具有了更优的动态性能。3)进一步考虑更为隐蔽的FDI攻击,首先,从攻击者视角深入分析了隐蔽FDI攻击的实施过程,并给出了依赖系统输出的非线性隐蔽FDI攻击模型描述及其因满足的界限制条件;其次,综合考虑边缘智能设备的计算能力以及对隐蔽FDI攻击的有效防御策略,在DETCS下,重新构建了 ICPS综合安全控制框架;接着,对于非线性隐蔽FDI攻击下的ICPS,通过在智能传感单元引入鲁棒性较强的滑模观测器,分别给出了状态、隐蔽FDI攻击及执行器故障估计方法;再者,采用基于估计、补偿的综合安全控制策略,并结合事件触发条件,给出了综合安全控制与通讯协同设计方法;最后,通过仿真实验验证了所提方法的有效性,结果表明在非线性隐蔽FDI攻击下,采用滑模观测器可得到更为准确的估计结果,因而更利于提升ICPS综合安全控制水平。

关键词：工业信息物理融合系统假数据注入攻击执行器故障离散事件触发机制控制与通讯协同设计

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A Multi-Synchronous Bi-Directional NoC (MBiNoC) architecture with dynamic self-reconfigurable channel for the GALS infrastructure

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ALEXANDRIA ENGINEERING JOURNAL 2018年第2期57卷 739-754页

作者： Kamal, Rajeev Moreno Arostegui, Juan M. Univ Politecn Cataluna Dept Elect Engn Barcelona Spain

To enhance the performance of on-chip communications of Globally Asynchronous Locally Synchronous systems (GALS), a dynamic reconfigurable multi-synchronous router architecture is proposed to increase network on chip (NoC) efficiency by changing the path of the communication link in the runtime traffic situation. In order to address GALS issues and bandwidth requirements, the proposed multi-synchronous bidirectional NoC's router is developed and it guarantees higher packet consumption rate, better bandwidth utilization with lower packet delivery latency. all the input/output ports of the proposed router behave as a bi-directional ports and communicate through a novel multi-synchronous first-in first-out (FIFO) buffer. The bidirectional port is controlled by a dynamic channel control module which provides a dynamic reconfigurable channel to the router itself and associated sub-modules. This proposed multi-synchronous bidirectional router architecture is synthesized using Xilinx ISE 14.7 and FPGA Virtex 6 family device XC6VLX760 is considered as target technology and its performance is evaluated in terms of power, area and delay. (C) 2017 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V.

关键词： network-on-Chip (NoC) GALS Bidirectional channel Multi-synchronous FIFO On-chip communications

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New Insights on Channel Hardening in Cell-Free Massive MIMO networks

New Insights on Channel Hardening in Cell-Free Massive MIMO ...

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IEEE International Conference on communications Workshops, ICC

作者： Alberto Álvarez Polegre Felip Riera-Palou Guillem Femenias Ana García Armada Universidad Carlos III de Madrid Getafe Spain Mobile Communications Group Universitat de les Illes Balears

ISBN: (数字)9781728174402

ISBN: (纸本)9781728174419

The cell-free (CF) massive multiple-input multiple-output (M-MIMO) architecture has recently emerged as a key technology for future wireless networks that is shown to outperform alternative network deployments such as those based on small-cells. Despite the many characteristics CF-M-MIMO shares with conventional M-MIMO (i.e., centralized) systems, its distributed nature brings along new issues that need to be carefully accounted for. In particular, the so-called channel hardening effect that postulates that the variance of the compound wireless channel experienced by a given user from a large number of transmit antennas tends to vanish, effectively making the channel deterministic. This critical assumption, which permeates most theoretical results of M-MIMO, has been well investigated and validated in centralized architectures, however, it has received little attention in the context of CF-M-MIMO networks. Hardening in CF-M-MIMO is potentially compromised by the different large-scale gains each access point (AP) impinges to the transmitted signal to each user, a condition that is further stressed when not all APs transmit to all users as proposed in the user-centric (UC) variations of CF-M-MIMO. This paper aims at presenting a comprehensive study of the channel-hardening effect in CF-M-MIMO under realistic operational conditions (e.g, presence of pilot contamination, power control, different precoders). Closed-form expressions of the hardening coefficient for different precoding schemes are provided showing that the precoder's choice, the number of antennas at each AP and the geographical density of APs play a key role in achieving this property.

关键词： Channel estimation Precoding MIMO communication Downlink Training Contamination Uplink

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Resilient optical networks1 20

Resilient Optical Networks1

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20th International Conference on Transparent optical networks, ICTON 2018

作者： Chan, Vincent W.S. Claude E. Shannon Communication and Network Group Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology United States

ISBN: (纸本)9781538666043

networking resilience is the ability to provide and maintain an acceptable level of service, albeit potentially degraded from nominal, in the face of faults and challenges to normal, including adversarial attacks. This paper explores the concept of resilient optical networks and scopes the important issues to be addressed in a sensible architecture. The solution includes monitoring and probing to determine the states of potentially unreliable network substrates, assessment of resilient network operating regimes, isolation of compromised assets, deployment of mitigation measures that may require communication over unreliable substrates and suggestions for resilient architecture design and improvement. The architecture construct evolves around a robust control plane that uses cognitive techniques to assess network states and automatically reacts to the on-set of impairments and attacks involving all the network layers from the Physical Layer to the Application Layer. © 2018 IEEE.

关键词： network security

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6G wireless communication systems: Applications, requirements, technologies, challenges, and research directions

arXiv

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arXiv 2019年

作者： Chowdhury, Mostafa Zaman Shahjalal, Md Ahmed, Shakil Jang, Yeong Min Dept. of Electronics Engineering Kookmin University Seoul Korea Republic of Dept. of Electrical and Electronic Engineering Khulna University of Engineering & Technology Khulna Bangladesh Dept. of Electrical and Computer Engineering University of Arizona United States

—Fifth-generation (5G) communication, which has many more features than fourth-generation communication, will be officially launched very soon. A new paradigm of wireless communication, the sixth-generation (6G) system, with the full support of artificial intelligence is expected to be deployed between 2027 and 2030. In beyond 5G, there are some fundamental issues, which need to be addressed are higher system capacity, higher data rate, lower latency, and improved quality of service (QoS) compared to 5G system. This paper presents the vision of future 6G wireless communication and its network architecture. We discuss the emerging technologies such as artificial intelligence, terahertz communications, optical wireless technology, free space optic network, blockchain, three-dimensional networking, quantum communications, unmanned aerial vehicle, cell-free communications, integration of wireless information and energy transfer, integration of sensing and communication, integration of access-backhaul networks, dynamic network slicing, holographic beamforming, and big data analytics that can assist the 6G architecture development in guaranteeing the QoS. We present the expected applications with the requirements and the possible technologies for 6G communication. We also outline the possible challenges and research directions to reach this goal. Copyright © 2019, The Authors. all rights reserved.

关键词： 5G mobile communication systems

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6G时代信息新鲜度优先的无线网络设计

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物联网学报 2020年第1期4卷 80-91页

作者：熊轲胡慧敏艾渤张煜裴丽北京交通大学计算机与信息技术学院北京100044 轨道交通控制与安全国家重点实验室北京100044 国网能源研究院有限公司北京102209 北京交通大学全光网与现代通信网教育部重点实验室北京100044

物联网的发展催生了各类实时监测系统(如智能驾驶)和状态更新系统(如工业控制)的部署与应用。对于上述系统而言,信息新鲜度至关重要。若目的端接收的是过时信息,可能会降低系统决策的准确性和可靠性,并造成巨大的安全隐患。在未来6G网络... 详细信息

物联网的发展催生了各类实时监测系统(如智能驾驶)和状态更新系统(如工业控制)的部署与应用。对于上述系统而言,信息新鲜度至关重要。若目的端接收的是过时信息,可能会降低系统决策的准确性和可靠性,并造成巨大的安全隐患。在未来6G网络中,信息新鲜度对信息更新应用将越来越重要。为了有效地刻画信息新鲜度,学术界提出了信息年龄(AoI,age of information)的概念。目前,AoI已迅速成为无线系统新的性能指标和研究热点。首先概述了AoI的研究历程,然后分析了在不同网络模型(如单用户网络、单跳网络和多用户网络等)中引入AoI的关键问题,最后对未来的研究趋势进行了展望。

关键词： 6G 物联网信息新鲜度信息年龄

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Cooperative intersection crossing over 5G

arXiv

引用

arXiv 2019年

作者： Castiglione, Luca Maria Falcone, Paolo Petrillo, Alberto Romano, Simon Pietro Santini, Stefania Department of Computing Imperial College London DIETI University of Napoli Federico II Napoli Italy Department of Electrical Engineering Chalmers University of Technology Gothenburg Sweden

Autonomous driving is a safety critical application of sensing and decision-making technologies. communication technologies extend the awareness capabilities of vehicles, beyond what is achievable with the on-board systems only. Nonetheless, issues typically related to wireless networking must be taken into account when designing safe and reliable autonomous systems. The aim of this work is to present a control algorithm and a communication paradigm over 5G networks for negotiating traffic junctions in urban areas. The proposed control framework has been shown to converge in a finite time and the supporting communication software has been designed with the objective of minimizing communication delays. At the same time, the underlying network guarantees reliability of the communication. The proposed framework has been successfully deployed and tested, in partnership with Ericsson AB, at the AstaZero proving ground in Goteborg, Sweden. In our experiments, three autonomous vehicles successfully drove through an intersection of 235 square meters in a urban scenario. Copyright © 2019, The Authors. all rights reserved.

关键词： 5G mobile communication systems

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Cognitive Radio Based Smart Grid communication System

Cognitive Radio Based Smart Grid Communication System

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作者： Sheraz Alam Khan INTERNATIONAL ISLAMIC UNIVERSITY ISLAMABAD

学位级别：博士

Smart grid (SG) concepts have revolutionized the future of conventional electric grid by making it more efficient, resilient and reliable using state-of-the-art technologies, modern equipment, and automation control systems. However, the full realization of all the above-mentioned benefits is not possible without the implementation of a fast, reliable and economical communication network that must exhibit spectral and energy efficiency. Additionally, the data generated by various SG applications is not only in enormous proportion but also diverse in nature in terms of its delay tolerance. The crucial need to transmit a significant amount of smart grid applications data in a spectral efficient manner makes cognitive radio (CR) technology most suitable for SG environment. Identically, TV white spaces (TVWS) is the most expectant candidate for CR based smart grid communication network (CRSGCN). Using CR in SGCN will bring its own set of communication problems. There is not much of a research available for problems associated with CRSGCN and primarily, this is the motivation behind this research work. This dissertation addresses some critical challenges in the design of CRSGCN. The research work can be divided into two parts. First, we present a comprehensive survey to establish the diverse communication requirements for three subsets of SGCN: Home Area network (HAN), Neighborhood Area network (NAN) and Wide Area network (WAN). Then, we review SG applications to analyze what kind of data is suitable to be carried over CR technology. Based on these requirements, we propose a CR based end- to-end network architecture for SGCN by using IEEE communication standards suitable for delay-tolerant data such as required by automatic metering infrastructure (AMI) and demand response (DR) etc. Then, we identify salient features of the proposed network architecture that makes it a viable solution along with some open issues and challenges, related to CRSGCN. The second part is then

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ADYTIA: Adaptive and Dynamic TCP Interface architecture for heterogeneous networks

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INTERNATIONAL JOURNAL OF communication systems 2019年第2期32卷 e3855-e3855页

作者： Vanzara, Rakeshkumar Sharma, Priyanka Bhatt, Haresh S. Tanwar, Sudeep Tyagi, Sudhanshu Kumar, Neeraj Obaidat, Mohammad S. Ganpat Univ UV Patel Coll Engn Mehsana India Nirma Univ Inst Technol Dept Comp Engn Ahmadabad Gujarat India ISRO Space Applicat Ctr Ahmadabad Gujarat India Deemed Univ Thapar Inst Engn & Technol Dept Elect & Commun Engn Patiala Punjab India Deemed Univ Thapar Inst Engn & Technol Dept Comp Sci & Engn Patiala Punjab India Nazarbayev Univ ECE Dept Astana Kazakhstan Univ Jordan King Abdullah II Sch IT Amman Jordan

Due to the widespread popularity and usage of Internet of things (IoT)-enabled devices, there is an exponential increase in the data traffic generated from these IoT devices. Most of these devices communicate with each other using heterogeneous links having constraints such as latency, throughput, and interference from concurrent transmissions. This results in an extra burden on the underlying communication infrastructure to manage the traffic within these constraints between source and destination. However, most of the existing applications use different Transmission control Protocol (TCP) variants for traffic management between these devices and are dependent on the stage of the sender, irrespective of the application types and link characteristics. Each operating system (OS) has different TCP variant for all applications, irrespective of path characteristics. Hence, a single TCP variant cannot select the best suitable link, which results in degradation in throughput compared to the existing default. Moreover, it cannot use the full capacity of the available link for different applications and network links, especially in heterogeneous network such as IoT. To cope up with these challenges, in this paper, we propose an Adaptive and Dynamic TCP Interface architecture (ADYTIA). ADYTIA allows the usage of different TCP variants based on application and link characteristics, irrespective of the physical links of the entire path. It allows the usage of different TCP variants based on their design principle across heterogeneous technologies, platforms, and applications. ADYTIA is implemented on NS-2 and Linux kernel for real testbed experiments. Its ability to select the best suitable TCP variant results in 20% to 80% improvement in throughput compared with the existing default and single TCP variant on Linux and Windows.

关键词： heterogeneous networks internetworking operating systems TCPIP transport protocols

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