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Correlating the Effect of Covid-19 Lockdown with Mobility Impacts: A time Series Study Using Noise Sensors Data

Transportation research Procedia 2022年 62卷 115-122页

作者： Antonio Pascale Simona Mancini Pedro M. d’Orey Claudio Guarnaccia Margarida C. Coelho Centre for Mechanical Technology and Automation Dept. of Mechanical Engineering University of Aveiro Campus Universitário de Santiago 3801-193 Aveiro Portugal Department of Information and Electric Engineering and Applied Mathematics University of Salerno Via Giovanni Paolo II 132 I-84084 Fisciano Italy Real-Time and Embedded Computing Systems Research Centre (CISTER) ISEP IPP Rua Dr. António Bernardino de Almeida 431 4200-072 Porto Portugal Dept. of Civil Engineering University of Salerno Via Giovanni Paolo II 132 I-84084 Fisciano Italy

The Covid-19 crisis forced governments around the world to rapidly enact several restrictions to face the associated health emergency. The Portuguese government was no exception and, following the example of other countries, established various limitations to flat the contagions curve. This led to inevitable repercussions on mobility and environmental indicators including noise. This research aims to assess the impact of the lockdown due to Covid-19 disease on the noise levels recorded in the city of Porto, Portugal. Data from four noise sensors located in strategic spots of the city were used to calibrate and validate time Series Models, allowing to impute the missing values in the datasets and rebuild them. The trend and the cyclic information were extracted from the reconstructed datasets using decomposition techniques. Finally, a Spearman correlation analysis between noise levels values and traffic volumes (extracted from five inductive loop detectors, located nearby the noise sensors) was performed. Results show that the noise levels series present a daily seasonal pattern and the trends values decreased from 6.7 to 7.5 dBA during the first lockdown period (March-May 2020). Moreover, the noise levels tend to gradually rise after the removal of restrictions. Finally, there is a monotonic relationship between noise levels and traffic volumes values, as confirmed by the positive moderate-to-high correlation coefficients found, and the sharp drop of the former during March-May 2020 can be attributed to the strong reduction of road traffic flows in the city.

关键词： Traffic Noise time Series Models Covid-19 Inductive Loops

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Secure wireless avionics intra-communications: The SCOTT approach

Ada User Journal

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Ada User Journal 2018年第4期39卷 267-276页

作者： Samano-Robles, Ramiro Neves, José Research Centre in Real-time and Embedded Computing Systems Porto Portugal GMVIS SKYSOFTSA Lisbon Portugal

This paper presents the objectives and architecture of the use case of secure wireless avionics intracommunications of the European Project SCOTT (secure connected trustable things). SCOTT aims to build trust of the Internet of Things (IoT) in industrial applications. SCOTT addresses multiple issues such as security, safety, privacy, and dependability across 5 industrial domains: automotive, aeronautics, railway, building and healthcare. The aeronautics use case focuses on the application for active flow control (AFC) based on dense wireless sensor and actuator networks (DWSANs). Topics about security, vulnerabilities and safety in the general field of wireless avionics intra-communications (WAICs) will be addressed. The paper presents preliminary conclusions of the vulnerabilities and security solutions across different entities and layers of the aeronautics IoT architecture. © 2018 *** rights reserved.

关键词： Internet of things

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Attack Detection in Cyber-Physical Production systems using the Deterministic Dendritic Cell Algorithm

Attack Detection in Cyber-Physical Production Systems using ...

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International Conference on Emerging Technologies and Factory Automation (ETFA)

作者： Rui Pinto Gil Gonçalves Eduardo Tovar Jerker Delsing Research Center for Systems and Technologies Faculty of Engineering University of Porto Porto Portugal Research Centre in Real-Time and Embedded Computing Systems Polytechnic of Porto - School of Engineering Porto Portugal EISLAB Luleå University of Technology Luleå Sweden

ISBN: (数字)9781728189567

ISBN: (纸本)9781728189574

Cyber-Physical Production systems (CPPS) are key enablers for industrial and economic growth. The introduction of the Internet of Things (IoT) in industrial processes represents a new revolution towards the Smart Manufacturing oncept and is usually designated as the 4 th Industrial Revolution. Despite the huge interest from the industry to innovate their production systems, in order to increase revenues at lower costs, the IoT concept is still immature and fuzzy, which increases security related risks in industrial systems. Facing this paradigm and, since CPPS have reached a level of complexity, where the human intervention for operation and control is becoming increasingly difficult, Smart Factories require autonomic methodologies for security management and self-healing. This paper presents an Intrusion Detection System (IDS) approach for CPPS, based on the deterministic Dendritic Cell Algorithm (dDCA). To evaluate the dDCA effectiveness, a testing dataset was generated, by implementing and injecting various attacks on a OPC UA based CPPS testbed. The results show that these attacks can be successfully detected using the dDCA.

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Poster Abstract: Privacy-preserving Control Message Dissemination for PVCPS

Poster Abstract: Privacy-preserving Control Message Dissemin...

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International Symposium on Information Processing in Sensor Networks (IPSN)

作者： Kai Li Yousef Emami Eduardo Tovar Real-Time and Embedded Computing Systems Research Centre (CISTER) Porto Portugal

ISBN: (纸本)9781728107271

Privacy preservation is critical for control information dissemination in Platoon-based Vehicular Cyber-Physical systems (PVCPS). However, the vehicular communication is vulnerable to wireless eavesdropping attack and message modification, due to broadcast nature of radio channels. In this poster, we present a secret key generation testbed for PVCPS security, which is built based on off-the-shelf autonomous robotic vehicles and TelosB wireless transceivers. A cooperative secret key agreement (CoopKey) scheme is demonstrated for encrypting/decrypting the disseminated control messages. To unify the secret key generated by the vehicles, CoopKey explores received signal strength (RSS) measurements and channel estimation on the inter-node radio channel. In addition, a Python-based user interface is also implemented to show real-time bit mismatch rate of CoopKey.

关键词： Lead Wireless communication real-time systems Security Cyber-physical systems Communication system security embedded computing

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On-board deep Q-network for UAV-assisted online power transfer and data collection

arXiv

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arXiv 2019年

作者： Li, Kai Ni, Wei Tovar, Eduardo Real-Time and Embedded Computing Systems Research Centre Portugal Commonwealth Scientific and Industrial Research Organization Australia

Unmanned Aerial Vehicles (UAVs) with Microwave Power Transfer (MPT) capability provide a practical means to deploy a large number of wireless powered sensing devices into areas with no access to persistent power supplies. The UAV can charge the sensing devices remotely and harvest their data. A key challenge is online MPT and data collection in the presence of on-board control of a UAV (e.g., patrolling velocity) for preventing battery drainage and data queue over ow of the sensing devices, while up-to-date knowledge on battery level and data queue of the devices is not available at the UAV. In this paper, an on-board deep Q-network is developed to minimize the overall data packet loss of the sensing devices, by optimally deciding the device to be charged and interrogated for data collection, and the instantaneous patrolling velocity of the UAV. Specifically, we formulate a Markov Decision Process (MDP) with the states of battery level and data queue length of sensing devices, channel conditions, and waypoints given the trajectory of the UAV;and solve it optimally with Q-learning. Furthermore, we propose the on-board deep Q-network that can enlarge the state space of the MDP, and a deep reinforcement learning based scheduling algorithm that asymptotically derives the optimal solution online, even when the UAV has only outdated knowledge on the MDP states. Numerical results demonstrate that the proposed deep reinforcement learning algorithm reduces the packet loss by at least 69.2%, as compared to existing non-learning greedy algorithms. Copyright © 2019, The Authors. All rights reserved.

关键词： Energy transfer

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Security in Wireless Sensor Networks: A formal verification of protocols

Security in Wireless Sensor Networks: A formal verification ...

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IEEE International Conference on Industrial Informatics (INDIN)

作者： Giann Spilere Nandi David Pereira Martín Vigil Ricardo Moraes Analúcia Schiaffino Morales Gustavo Araújo CISTER - Research Centre in Real-Time & Embedded Computing Systems Portugal >Universidade Federal de Santa Catarina Brazil

The increase of the digitalization taking place in various industrial domains is leading developers towards the design and implementation of more and more complex networked control systems (NCS) supported by Wireless Sensor Networks (WSN). This naturally raises new challenges for the current WSN technology, namely in what concerns improved guarantees of technical aspects such as real-time communications together with safe and secure transmissions. Notably, in what concerns security aspects, several cryptographic protocols have been proposed. Since the design of these protocols is usually error-prone, security breaches can still be exposed and MALICIOUSly exploited unless they are rigorously analyzed and verified. In this paper we formally verify, using ProVerif, three cryptographic protocols used in WSN, regarding the security properties of secrecy and authenticity. The security analysis performed in this paper is more robust than the ones performed in related work. Our contributions involve analyzing protocols that were modeled considering an unbounded number of participants and actions, and also the use of a hierarchical system to classify the authenticity results. Our verification shows that the three analyzed protocols guarantee secrecy, but can only provide authenticity in specific scenarios.

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Performance Analysis of Network Diversity Multiple Access with Sequential Terminal Detection and Non-Orthogonal Training Sequences

Performance Analysis of Network Diversity Multiple Access wi...

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IEEE Vehicular Technology Conference

作者： Ramiro Samano-Robles Research Centre in Real-time and Embedded Computing Systems Porto Portugal

This paper presents a new approach for terminal presence detection in the family of algorithms called network diversity multiple access (NDMA). In NDMA, system-induced retransmissions are used to resolve the conflicts between colliding terminals. The key initial aspect in NDMA is to use signal processing tools to identify the size of the collision, as well as the identity of the contending terminals. This information is used to calculate the number of required retransmissions. These retransmissions are stored in memory, thereby creating a virtual MIMO (multiple input multiple-output) system that can be used to resolve the collision via source separation or multiuser detection. These detection and source separation processes are based on a set of orthogonal training sequences, each sequence uniquely assigned to one terminal in the network. This paper proposes a new approach for presence detection in NDMA using non-orthogonal sequences. The number of available sequences is increased and the bandwidth used for training is therefore considerably reduced. This comes at the expense of multiple access interference (MAI) between contending terminals. Additionally, in NDMA the estimation of the collision multiplicity is conventionally achieved exclusively in the first time-slot of the collision resolution period. This paper extends the detector to include all the received copies of the original transmissions (the initial transmission and also subsequent retransmissions). This means that after each retransmission is received by the access point, the estimation of the collision multiplicity and contending terminals identification must be updated. The analysis here presented includes the effects of MAI caused by non orthogonal training sequences and the effect of sequential collision multiplicity estimation. Results suggest a considerably decrease of detection performance with respect to the orthogonal case scenario, but a more flexible training sequence allocation that becomes

关键词： Estimation Training Signal resolution Protocols MIMO communication Detectors Probability density function

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Using Coalition Games for QoS Aware Scheduling in mmWave WPANs

Using Coalition Games for QoS Aware Scheduling in mmWave WPA...

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IEEE Vehicular Technology Conference

作者： Yali Chen Yong Niu Bo Ai Zhangdui Zhong Dapeng (Oliver) Wu Kai Li School of Electronic and Information Engineering of Beijing Jiaotong University Beijing China Department of Electrical and Computer Engineering University of Florida Gainesville FL USA Real-Time and Embedded Computing Systems Research Centre (CISTER) Porto Portugal

With the increasing quality of service (QoS) demands for indoor multimedia applications, millimeter wave (mmWave) communications are emerging as a promising candidate for the wireless personal area networks (WPANs). On the one hand, it has the advantage of providing several-Gbps transmission rate. However, due to the unique characteristics in 60-GHz frequency band, such as high propagation loss, beamforming is fully exploited for mmWave links to achieve directional transmission and reception. In this paper, we propose a novel QoS aware scheduling algorithm for concurrent transmission in mmWave WPANs based on coalition game. First, we formulate the problem of concurrent transmission scheduling into a non-convex integer programming problem. Then, we propose a coalition game based algorithm to maximize the number of flows satisfying the corresponding QoS requirements, while improving the network resource utilization effectively. Besides, our proposed algorithm converges to a Nash-stable equilibrium with greatly reduced complexity. Through extensive simulations under various system parameters, we demonstrate our scheme achieves better network performance in terms of the throughput and the number of flows scheduled successfully, compared with existed protocols.

关键词： Quality of service Interference Games Wireless personal area networks Resource management Scheduling algorithms Transmitters

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Network diversity multiple access with imperfect channel state information at the transmitter side

Network diversity multiple access with imperfect channel sta...

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Advances in Wireless and Optical Communications (RTUWO)

作者： Ramiro Sámano-Robles Research Centre in Real-time and Embedded Computing Systems Porto Portugal

ISBN: (纸本)9781509015368

Network diversity multiple access (NDMA) is the family of algorithms with the highest potential throughput in the literature of signal-processing assisted random access protocols. NDMA uses the concept of protocol-induced retransmissions to create an adaptive source of diversity. This diversity is used to resolve packet collisions employing signal separation tools without the explicit need (or as a complement) of a multiple antenna receiver. This paper proposes a further improvement on the performance of NDMA by allowing each terminal access to an outdated copy of its individual channel state information (CSI). Based on this decentralized CSI, each terminal conveniently decides to transmit only if the estimated channel gain surpasses a threshold that is optimized to maximize performance. This ensures that the probability of terminal presence detection, and thus the probability of correct estimation of the collision multiplicity are considerably improved at the receiver end. The paper is focused on the modelling of the receiver operational characteristic (ROC) of the terminal presence detector considering that the CSI used by each terminal is potentially inaccurate (outdated) due to feedback delay. The results indicate that when the correlation coefficient that describes the accuracy of the available CSI tends to zero (ρ → 0), the scheme degrades into the conventional NDMA. By contrast, when the quality of the channel state information improves (ρ → 1), the throughput can nearly achieve the nominal channel rate (minimum throughput penalty). The selection of the detector thresholds for channel gain and terminal presence is optimized to maximize system performance.

关键词： Protocols Receivers Estimation Channel state information Signal resolution Channel estimation MIMO

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Adding quality in the user requirements specification: A first approach 11

Adding quality in the user requirements specification: A fir...

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2016 11th International Conference on Digital Information Management, ICDIM 2016

作者： Guerra-Garcia, Cesar Caballero, Ismael Cardenas-Juarez, Marco Samano-Robles, Ramiro Information Technology Department UPSLP San-Luis-Potosi Mexico Department of Information Technologies UCLM Ciudad Real Spain Faculty of Sciences UASLP San-Luis-Potosí Mexico Research Centre in Real-time and Embedded Computing Systems Porto Portugal

ISBN: (纸本)9781509026401

Users need trusting in data managed by software applications that are part of Information systems (IS), which supposes that organizations should assuring adequate levels of quality in data that are managed in their IS. Therefore, the fact that an IS can manage data with an adequate level of quality should be a basic requirement for all organizations. In order to reach this basic requirement some aspects and elements related with data quality (DQ) should be taken in account from the earliest stages of development of software applications, i.e. 'data quality by design'. Since DQ is considered a multidimensional and largely context-dependent concept, managing all specific requirements is a complex task. The main goal of this paper is to introduce a specific methodology, which is aimed to identifying and eliciting DQ requirements coming from different viewpoints of users. These specific requirements will be used as normal requirements (both functional and non-functional) during the development of IS awareness of data quality. © 2016 IEEE.

关键词： Information systems

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