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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigation of Services and Application Scenarios for Inter-Vehicle Communication

Vianney Hakizamana, Jean Marie January 2007 (has links)
<p>In recent years, the number of vehicles has increased dramatically in Europe, USA and Japan. This causes a high traffic density and makes new security features a crucial point in order to keep the traffic safe. Inter-vehicle communication offers solutions in this field, as cars can communicate with each other. To this date, there is no special technology standardized for inter-vehicle communication. This is the reason why car makers, researchers and academics have invested money and time in different research projects so that in future they may come up with a common solution. Some of the technologies like DSRC, CALM, IEEE 802.11 or Infrared are thought to be more reliable than others according to different authors [9][23].</p><p>The technologies described above will help to improve road safety and application scenarios like lane change, blind merge or pre and post crash situations can be addressed. The position of each car is known through a GPS; speed, heading and other dynamic data of a car are known to all cars in the same vicinity.</p><p>In this thesis, a thorough investigation of services and applications related to inter-vehicular communication technology (i.e. car-to-car and car-to-infrastructure or vice versa) will be carry out. The emphasis will be on requirements on the communication system, sensors and user interface in order to make the technology more useful for future vehicle alert system and to avoid as many of the mentioned scenarios as possible. A rear-end collision can be avoided if the driver is warned within 0 to 5 second of potential accident.</p>
2

Investigation of Services and Application Scenarios for Inter-Vehicle Communication

Vianney Hakizamana, Jean Marie January 2007 (has links)
In recent years, the number of vehicles has increased dramatically in Europe, USA and Japan. This causes a high traffic density and makes new security features a crucial point in order to keep the traffic safe. Inter-vehicle communication offers solutions in this field, as cars can communicate with each other. To this date, there is no special technology standardized for inter-vehicle communication. This is the reason why car makers, researchers and academics have invested money and time in different research projects so that in future they may come up with a common solution. Some of the technologies like DSRC, CALM, IEEE 802.11 or Infrared are thought to be more reliable than others according to different authors [9][23]. The technologies described above will help to improve road safety and application scenarios like lane change, blind merge or pre and post crash situations can be addressed. The position of each car is known through a GPS; speed, heading and other dynamic data of a car are known to all cars in the same vicinity. In this thesis, a thorough investigation of services and applications related to inter-vehicular communication technology (i.e. car-to-car and car-to-infrastructure or vice versa) will be carry out. The emphasis will be on requirements on the communication system, sensors and user interface in order to make the technology more useful for future vehicle alert system and to avoid as many of the mentioned scenarios as possible. A rear-end collision can be avoided if the driver is warned within 0 to 5 second of potential accident.
3

Mathematical modelling of aperture coupled patch antennas with multi-layered superstrates

Robinson, Bryan January 1997 (has links)
No description available.
4

Model Predictive Control for Heavy Duty Vehicle Platooning / Modellbaserad prediktionsreglering för tunga fordon i fordonståg

Kemppainen, Josefin January 2012 (has links)
The aim of platooning is to enable several vehicles to drive in a convoy while each vehicle is controlled autonomously in longitudinal direction. All vehicles in the platoon are equipped with WiFi and can therefore apply Vehicle-to-Vehicle (V2V) communication. As a result, a short intermediate distance between the vehicles can be maintained. Reduction of the aerodynamic drag is the result of the short distance, which in turn, reduces the consumed fuel. This thesis is a part of a larger project, consisting of two other theses that investigate estimation of the sensor data. Other scenarios that may arise with the platooning concept, e.g. packet losses and time synchronization of the different sensors are also analyzed. The purpose of this master thesis is to develop and evaluate a Model Predictive Control (MPC) in the concept of platooning. The main focus lies on implementation of two types of MPC, centralized and distributed, and later on integration with the other two subsystems is performed. Results from the MPC itself are evaluated, principally in terms of fuel con- sumption and computational demand. The major part of the results are based on the complete system as one unit and covers different test scenarios such as WiFi loss and non-transmitting vehicle entering the platoon. A comparison of how much energy that is consumed by the engine between an HDV driving with its cruise control and an HDV driving in a platoon has been performed. With an intermediate distance of 10 meters, driving with varying velocity and ideal signals the energy consumption got reduced with an average of 11%. / Syftet med platooning är att flera tunga fordon kör tätt efter varandra i ett fordonståg. Varje fordon regleras autonomt i longitudinell riktning och är utrustad med WiFi. Detta bidrar till att fordonen kan kommunicera med varandra och denna kommunikation, även kallad Vehicle-to-Vehicle (V2V) - communication, leder till att det relativa avståndet mellan fordonen kan minskas, vilket i sin tur leder till minskat luftmotstånd och därmed minskad bränsleförbrukning. Detta examensarbete är en del av ett större projekt som består av ytterligare två examensarbeten. De andra två hanterar estimeringen av sensordata samt behandlar förlorat sensordata och tidssynkronisering av de olika sensorerna som används. Syftet med detta examensarbete är att utveckla och utvärdera en MPC regu- lator i platooning sammanhang. Huvudfokuset ligger på implementeringen, både centraliserad och distribuerad MPC, och integreringen med de två andra delsystemen. Resultaten från enbart MPC utvärderas i termer av bränsleförbrukning och även beräkningskapactiet, då MPC är känt för att vara väldigt beräkningskrävan- de och är ofta en begränsning för hårdvaran. Den största delen av resultaten är baserade på hela systemet och täcker olika scenarion som exempelvis dålig WiFi uppkoppling och att icke−sändande fordon intar platoonen. En jämförelse av hur mycket energi motorn förbrukade har gjorts mellan ett tungt fordon som kör med farthållaren påslagen och ett tungt fordon som kör i en platoon. Med ett relativt avstånd på 10 meter, varierande hastighet och icke brusiga signaler kan bränsleförbrukning minskas med ett medel på approximativt 11%.
5

A SystemC simulator for the dynamic segment of the FlexRay protocol

Podduturi, Venkata Rama Krishna Reddy January 2012 (has links)
FlexRay, developed by a consortium of over hundred automotive companies, is a real-time in-vehicle communication protocol for automotive networks. It is being used as a higher-performance, time-triggered, and deterministic serial bus in automobiles for many safety-critical and x-by-wire systems. In x-by-wire systems the hydraulic parts of systems such as steering and braking are replaced with electronics. As x-by-wire systems are safety-critical, they must be fault-tolerant, deterministic, and should have synchronized time base (global time). FlexRay fulfils all these requirements as it is a deterministic and fault-tolerant serial bus system with data rates of 10 Mbps for extremely safety- and time-critical applications. As, FlexRay has become the de-facto standard for high speed safety-critical communications in automotive domain, and timing analysis of FlexRay still continues to generate significant research interest. The FlexRay allows both time-triggered and event-triggered messages. The static (ST) segment allows time-triggered transmission, while dynamic (DYN) segment allows event-triggered transmission. As the DYN segment transmits messages based on their priorities; so the delay suffered by a message depends on the interferences by its higher priority messages. Computing interferences of the higher priority messages is a challenging problem for the DYN segment of FlexRay [32]. So, in order to compute interferences of the higher priority messages one way is to use simulation technique. The SystemC simulator proposed in this thesis is used to model and simulate the behaviour of the DYN segment of the FlexRay protocol. This modelling and simulation is done on system level using the system description language SystemC. The simulator estimates the delay suffered by a message instances because of the interferences of higher priority messages. This estimation of delay is done by taking no-jitter/jitter into consideration. Finally, in both the cases the delay suffered by each and every message instance is plotted.
6

Modeling Information Propagation Along Traffic on Two Parallel Roads

Yin, Kai 2010 August 1900 (has links)
IntelliDrive systems, including inter-vehicle communication and vehicle infrastructure integration, aim to improve safety, mobility, and efficiency of transportation. They build on the wireless ad hoc network technologies, enabling vehicles to communicate with roadside infrastructure and with each other. The process of information propagation in a multi-hop network underlies the system design and efficiency. As of now, the research has been restricted to a single road of traffic. This work expands the study of information propagation to two parallel roads, a step further towards the discrete network case. This thesis presents two methodologies to model the process of information propagation. By identifying an approximate Bernoulli process, we are able to derive the expectation and variance of propagation distance. A road separation distance of square root of 3 over 2 times the transmission range distinguishes two cases for approximating the success probability in the Bernoulli process. In addition, our results take the single road as a special case. The numerical test shows that the developed approximation works well. This work further identities a Markov property for instantaneous information propagation along two parallel roads based on two types of transmission regions. Communication capable vehicles are assumed to follow two homogeneous Poisson processes on both roads. The Markov property enables us to derive exact expectation and variance of the propagation distance and further, obtain a recursive formula for the probability distribution of successful propagation distance. The developed formulas enable numerical calculation of the characteristics of propagation process. We hope this research will shed light on studies of vehicular ad hoc networks on more general discrete roadway networks.
7

Performance Analysis and System Modelling of Ethernet-based In­ Vehicle Communication / Analys av prestanda och modellering av Ethernet-baserad fordonskommunikation

Qiu, Jiaheng January 2017 (has links)
While vehicle technology is rapidly advanced, advanced driver assistance system (ADAS) stays in focus. However, all of these growing automotive applications are driving up the bandwidth requirements, therefore vehicle networks require higher bandwidth and more deterministic real-time guarantees than before.Switched Ethernet is widely used for all kinds of applications, and it gradually moves into the automotive domain. The new specification of the IEEE 802.1 Audio/Video Bridging (AVB) standard provides the QoS features needed for ADAS data streaming.In this work, we study and analyse Ethernet-based invehicle communication of both legacy Ethernet and AVB Ethernet through a simulation approach to verify the automotive network performance. Furthermore, a system engineering approach is used to achieve a more model-based design of simulation and developing prototypes in the future. / Samtidigt som fordonsteknologin ökar snabbt, är det system för avancerad förarassistans (advanced driver assistance systems, ADAS) som står i fokus. Dessa ökande fordonsapplikationer driver på bandbreddskraven, och därför kräver fordonsnätverken högre bandbredd och mer determinisktiska realtidskrav än tidigare.Switchat nätverk (Switched Ethernet) används i alla möjliga applikationer och flyttar gradvis in i fordonsdomänen. Den nya specificationen av standarden IEEE 802.1 Audio/Video Bridging (AVB) tillhandahåller QoS (Quality of Service) funktioner för ADAS dataöverföring.I den här avhandlingen undersöks och analyseras Ethernetbaserad fordonskommunikation av både vanligt nätverk (Ethernet) och AVB Ethernet genom simulering för att verifiera nätverksprestandan för fordonsnätverket i fråga. En systemingenjörsinriktning har använts för att skapa en mer modell-baserad design av simuleringen, som även kan användas för att utveckla prototyper i framtiden.
8

Vehicle to Vehicle Communication in Level 4 Autonomy

Hajimirsadeghi, Seyedsalar 01 January 2017 (has links)
With the number of deaths, commute time, and injuries constantly rising due to human driving errors, it’s time for a new transportation system, where humans are no longer involved in driving decisions and vehicles are the only machine that decide the actions of a vehicle. To accomplish a fully autonomous world, it’s important for vehicles to be able to communicate instantly and report their movements in order to reduce accidents. This paper discusses four approaches to vehicle to vehicle communication, as well as the underlying standards and technology that enable vehicles to accomplish communicating.
9

Modelling the Level of Trust in a Cooperative Automated Vehicle Control System

Rosenstatter, Thomas January 2016 (has links)
Vehicle-to-Vehicle communication is the key technology for achieving increased perception for automated vehicles where the communication allows virtual sensing with the use of sensors placed in other vehicles. In addition, this technology also allows recognising objects that are out-of-sight. This thesis presents a Trust System that allows a vehicle to make more reliable and robust decisions. The system evaluates the current situation and generates a Trust Index indicating the level of trust in the environment, the ego vehicle, and the other vehicles. Current research focuses on securing the communication between the vehicles themselves, but does not verify the content of the received data on a system level. The proposed Trust System evaluates the received data according to sensor accuracy, behaviour of other vehicles, and the perception of the local environment. The results show that the proposed method is capable of correctly identifying various situations and discusses how the Trust Index can be used to make more robust decisions.
10

Self-Organizing Wireless Sensor Networks For Inter-Vehicle Communication

Iqbal, Zeeshan January 2006 (has links)
<p>Now a day, one of the most attractive research topics in the area of Intelligent Traffic Control is </p><p>Inter-vehicle communication (V2V communication). In V2V communication, a vehicle can </p><p>communicate to its neighbouring vehicles even in the absence of a central Base Station. The </p><p>concept of this direct communication is to send vehicle safety messages one-to-one or one-to- </p><p>many vehicles via wireless connection. Such messages are usually short in length and have very </p><p>short lifetime in which they must reach the destination. The Inter-vehicle communication system </p><p>is an ad-hoc network with high mobility and changing number of nodes, where mobile nodes </p><p>dynamically create temporary sensor networks and transferring messages from one network to </p><p>others by using multiple hops due to limitation of short range. </p><p> </p><p>The goal of the project is to investigate some basic research questions in order to organize such </p><p>sensor networks and at the same time highlight the appropriate routing protocol that support </p><p>mobile ad hoc networks in an efficient and reliable manner. </p><p> </p><p>In our investigation, we have answered the technical issues in order to construct a V2V </p><p>communication system. We have also studied some mobile ad hoc network routing protocols in </p><p>detail and then selected the DSR (Dynamic Source Routing) for our V2V communication and </p><p>then simulated it according to our system requirements. We are quite satisfied by the result of </p><p>DSR, but at the same time much more work is required to come up with an absolute application </p><p>for the end user.</p>

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