Utilising in-vehicle information to detect traffic conditions in vehicular ad-hoc networks

In the last decade, cooperative vehicular network has been one of the most studied areas for developing the intelligent transportation systems (ITS). It is considered as an important approach to share the periodic traffic situations over vehicular ad hoc networks (VANETs) to improve efficiency and safety over the road. In addition to the uses of ITS, VANETs will contribute in service access, cooperative driving, entertainment and navigation for cars of the future. Vehicle to vehicle and vehicle to infrastructure communication are two distinct avenues that make possible efficient delivery of messages through direct wireless transmissions in traffic regions. Furthermore, promising quality of communication performance is desirable for a communication system composed mostly if roaming participants; such a system needs to be dynamic, flexible and infrastructure-less. Thus VANET architecture is a natural fit for ITS. However, there are a number of issues in exchanging traffic data over high mobility of VANET, such as broadcast storms, hidden nodes and network instability. Therefore, vehicular traffic efficiency applications have been investigated recently using VANET. This aspect of research is primarily concerned with increasing the traffic awareness over roads. In this thesis, a novel model, Efficient Traffic Conditions Detection (ETraCD) is proposed to detect the traffic conditions utilising vehicles’ characteristics and in-vehicles sensors information to evaluate traffic situations that are gathered from the nodes (vehicles) in VANET. The model revolves around the core idea to what extent we will be considering the traffic characteristics between groups of cars rather than individual cars. This does not concern the physical transmission of data but the data processing in the network. More precisely, vehicles are clustered into traffic groups based on the similarity of sensors’s data. ETraCD (a) divides the situations of vehicles into clusters, (b) designs a set of metrics to get the correlations among vehicles and (c) detects the traffic condition in certain areas. These approaches have been simulated in NS3 network simulator to investigate the performance of stability of the network, latency, and the accuracy of traffic situations detection. The proposed model applies V2V clustering paradigm for detecting traffic conditions, it has been implemented and its features investigated through simulation runs. It shows the benefit of using the vehicular sensors informations such as ABS, windscreen lights and so on based on V2V communication to provide an efficient traffic conclusion in urban environment. Experiments also show improved overall performance when compared to previous protocols

Single and Multi-Hop Vehicular Visible and Infrared Light Communications

Visible light communications (VLC) have been proposed as a complementary technology in vehicular networks due to its several merits including high security, high scalability than RF technology. Notably, the RF technology established for vehicular networks best known as the dedicated short-range communications, supports many applications but doubts still exist on the capability of this technology to meet the low latency (where not more than 20 ms is required for pre-crash sensing and cooperative collision mitigation) and high reliability requirements in intelligent transport systems (ITS), when considering issues such as network outages as well as security issues. Of interest is the wide increase in the use of light emitting diode (LED)-based vehicle and traffic lights, and cameras in vehicles (rear and dashcams), traffic and security cameras, hence opening more opportunities for the VLC technology as part of ITS. Remarkably, camera-based VLC (i.e., optical camera communications) offers even further capabilities such as vehicle localization, motion and scene detection and pattern recognition. However, the VLC system has few challenges that needs addressing for the practical implementation of this technology as part of ITS. Consequently, this thesis focuses on addressing the key challenges and proposing novel technical analytical and experimental solutions. Firstly, increasing the robustness to sunlight induced noise is one of the major challenges in vehicular VLC, hence this thesis proposes an infrared (IR) transmission, as the amount of solar irradiance is lesser in the IR band than in the visible band. Performance of the proposed scheme is validated through numerical simulations with realistic emulated sunlight noise from empirical measurement. Investigations on the effects of turbulence with aperture averaging and fog on vehicular VLC is also carried out via experiments. Secondly, increasing the communication range is another major challenge, consequently the feasibility of using different vehicle taillights (TLs) as the VLC transmitter are evaluated via simulations based on empirical measurements of the radiation characteristics and transmit powers of the TLs. Results obtained indicate that, only a very low link span of 89 m at the forward error correction (FEC) bit error rate (BER) limit of 3.8 × 10-3, compared to 4.5, 5.4, and 6.3 m for the BMW vehicle-based TL at data rates of 10, 6, and 2 Mbps are achieved under realistic sunlight conditions. While, to increase the communication distance of camera-based VLC links, reducing the spatial bandwidth of the camera in its out of focus regions is proposed, mathematically analysed, and experimentally demonstrated where up to a 400 m link span at a 100 % success reception rate is achieved at a data rate of 800 bps, which is the longest so far reported. Relay-assisted links are also investigated using amplify-and-forward (AF) and decode-and-forward (DF) relaying schemes under the emulated sunlight noise. A mathematical and simulation-based system model is developed, where different transmitter/receiver geometries are considered and AF and DF schemes. Results obtained via simulations shows that the DF scheme is a suitable candidate for vehicular VLC connectivity under emulated sunlight noise, offering at the FEC BER limit of 3.8 × 10-3 up to 150 % increase in the link distance by the end of the 2nd hop. Proof of concept experimental demonstration of AF and DF schemes for vehicular VLC are also carried out showing that DF is the preferred option. Moreover, insights are provided into the impact of various system parameters on the relay-assisted links. Finally, increasing the mobility of the vehicular VLC system is another major challenge, hence analysis on the required angular field of view (AFOV) for vehicular links considering necessary geometry parameters is investigated. Mathematical expressions to determine the required AFOV based on key system parameters are also derived. Furthermore, the relevance of the choice of the receiver parameters for an enhanced AFOV is also analysed, consequently a means to mitigate the effects of beam spot offset induced power losses at the photodiode caused by the misalignment of the transmitter and imaging receiver is proposed

Novel Internet of Vehicles Approaches for Smart Cities

Smart cities are the domain where many electronic devices and sensors transmit data via the Internet of Vehicles concept. The purpose of deploying many sensors in cities is to provide an intelligent environment and a good quality of life. However, different challenges still appear in smart cities such as vehicular traffic congestion, air pollution, and wireless channel communication aspects. Therefore, in order to address these challenges, this thesis develops approaches for vehicular routing, wireless channel congestion alleviation, and traffic estimation. A new traffic congestion avoidance approach has been developed in this thesis based on the simulated annealing and TOPSIS cost function. This approach utilizes data such as the traffic average travel speed from the Internet of Vehicles. Simulation results show that the developed approach improves the traffic performance for the Sheffield the scenario in the presence of congestion by an overall average of 19.22% in terms of travel time, fuel consumption and CO2 emissions as compared to other algorithms. In contrast, transmitting a large amount of data among the sensors leads to a wireless channel congestion problem. This affects the accuracy of transmitted information due to the packets loss and delays time. This thesis proposes two approaches based on a non-cooperative game theory to alleviate the channel congestion problem. Therefore, the congestion control problem is formulated as a non-cooperative game. A proof of the existence of a unique Nash equilibrium is given. The performance of the proposed approaches is evaluated on the highway and urban testing scenarios. This thesis also addresses the problem of missing data when sensors are not available or when the Internet of Vehicles connection fails to provide measurements in smart cities. Two approaches based on l1 norm minimization and a relevance vector machine type optimization are proposed. The performance of the developed approaches has been tested involving simulated and real data scenarios

Kommunikation und Bildverarbeitung in der Automation

In diesem Open Access-Tagungsband sind die besten Beiträge des 11. Jahreskolloquiums "Kommunikation in der Automation" (KommA 2020) und des 7. Jahreskolloquiums "Bildverarbeitung in der Automation" (BVAu 2020) enthalten. Die Kolloquien fanden am 28. und 29. Oktober 2020 statt und wurden erstmalig als digitale Webveranstaltung auf dem Innovation Campus Lemgo organisiert. Die vorgestellten neuesten Forschungsergebnisse auf den Gebieten der industriellen Kommunikationstechnik und Bildverarbeitung erweitern den aktuellen Stand der Forschung und Technik. Die in den Beiträgen enthaltenen anschauliche Anwendungsbeispiele aus dem Bereich der Automation setzen die Ergebnisse in den direkten Anwendungsbezug

Particle Physics Reference Library

This second open access volume of the handbook series deals with detectors, large experimental facilities and data handling, both for accelerator and non-accelerator based experiments. It also covers applications in medicine and life sciences. A joint CERN-Springer initiative, the “Particle Physics Reference Library” provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A,B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access

CACIC 2015 : XXI Congreso Argentino de Ciencias de la Computación. Libro de actas

Actas del XXI Congreso Argentino de Ciencias de la Computación (CACIC 2015), realizado en Sede UNNOBA Junín, del 5 al 9 de octubre de 2015.Red de Universidades con Carreras en Informática (RedUNCI