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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.
61

IN - eine verteilte Service-Plattform mobiler Prozeßarchitekturen für verkehrstelematische Anwendungen / IN - adistributed service platform of mobile process architectures for traffic telematic applications / traffic telematics IN (eng)

Riegelmayer, Wolfgang P. 14 February 2006 (has links) (PDF)
Der Paradigmenwechsel zur Entwicklungsmethodik innerhalb verteilter Kommunikationssysteme schlägt sich auch in der Telematik zum Anwendungspotential und Systemkomplexität nieder. Dies liefert eine neue Auffasung dessen, was den transparenten Datenkanal ausmacht.
62

IN - eine verteilte Service-Plattform mobiler Prozeßarchitekturen für verkehrstelematische Anwendungen

Riegelmayer, Wolfgang P. 09 January 2006 (has links)
Der Paradigmenwechsel zur Entwicklungsmethodik innerhalb verteilter Kommunikationssysteme schlägt sich auch in der Telematik zum Anwendungspotential und Systemkomplexität nieder. Dies liefert eine neue Auffasung dessen, was den transparenten Datenkanal ausmacht.
63

Channel measurement and communication module for the Grand Cooperative Driving Challenge

Bergh, Fredrik, Andersson, Johan January 2011 (has links)
Vehicular ad hoc networks (VANETs) are a hot topic in the intelligent transport system (ITS) area. The introduction of wireless communications between vehicles will enable many useful applications to enhance road traffic safety as well to increase efficiency. The standardization of IEEE 802.11p, being an amendment to IEEE 802.11 intended for VANETS, faces many challenges. In Europe a 30 MHz spectrum at 5.9 GHz have been dedicated for ITS and this spectrum has to be used to its full potential. For this reason this thesis compares a 20 MHz wide frequency channel with a 10 MHz wide through measurements using 802.11p hardware. The measurements were conducted on a highway with relative speeds of up to 240 km/h. The results from these initial measurements show that a 20 MHz channel does not perform worse than a 10 MHz channel despite the high relative speeds and large metal signs scattering the signals. What enabled this thesis to do the measurements was Halmstad University‟s participation in the Grand Cooperative Driving Challenge (GCDC) 2011. In GCDC nine teams mostly from Europe competed in having the vehicle that had the best behaviour in a platoon of vehicles using cooperative adaptive cruise control (CACC), the CACC algorithm controlled the vehicles‟ acceleration and breaking autonomously based on in-vehicle sensors and communicated messages between the vehicles in the platoon using 802.11p. This thesis implemented the communication part of Halmstad University‟s vehicle. The challenge was held in Helmond, Holland, May 14-15, 2011. Halmstad University‟s team finished in second place. / CoAct
64

Elimination of systematic faults and maintenance uncertainties on the City of Johannesburg's roads Intelligent Transport Systems

Makhwathana, Phalanndwa Lawrence 02 1900 (has links)
Road transport mobility continues to be a challenge to the City of Johannesburg (CoJ)’s economy in general. Traffic signals, their remote monitoring and control systems are the current implemented Intelligent Transport Systems (ITS), but daily systematic faults and maintenance uncertainties on such systems decrease the effectiveness of traffic engineers’ intersections optimization techniques. Inefficient electrical power supply to such ITS is a challenge, with conditional power cuts and fluctuations, uncertainties on traffic control system faults. Another factor leading to the problem is the communication channel which is using traditional modems which are not reliable. Reporting through both customer complaints and such unreliable remote monitoring systems makes maintenance to be ineffective. In this dissertation, the factors leading to the faults and uncertainties are considered. The proposed solution considers the important concerns of ITS, such as electrical power source performance optimization technique, road traffic control systems compatibility and communications systems / Electrical and Mining Engineering / M. Tech. (Electrical Engineering)
65

Localisation et transmissions sécurisées pour la communication Véhicule à Infrastructure (V2I) : Application au service de télépéage ITS-G5 / Localization and secure transmissions for Vehicle to Infrastructure communication (V2I) : Application to the electronic toll service using the ITS-G5 technology

Randriamasy, Malalatiana 24 May 2019 (has links)
La localisation précise des véhicules et la sécurité des échanges sont deux grands axes qui font la fiabilité des services fournis dans les systèmes de transport intelligent. Ces dernières années, elles font l’objet de nombreux projets de recherche pour des champs d’application divers. Dans cette thèse, le contexte d’application est la réalisation d’un service de télépéage utilisant la technologie ITS-G5. Cette technologie de communication sans-fil permet dans un premier temps le partage des informations de sécurité routière entre les véhicules (V2V), le véhicule et l’infrastructure (V2I). Dans cette thèse, on propose une architecture permettant d’échanger des transactions de télépéage utilisant les équipements communicants en ITS-G5 embarqués dans les véhicules connectés et les unités bord de route (UBR) de l’infrastructure. Les problématiques de nos travaux de recherche se concentrent sur la méthode de localisation des véhicules ayant effectué la transaction afin de pouvoir la valider et sur la sécurité de l’architecture proposée pour assurer l’échange de cette transaction. Afin de bien localiser les véhicules lors du passage au péage, notre approche propose la compréhension de la cinématique du véhicule par une modélisation adéquate à partir des données recueillies dans les messages coopératifs (CAM : Cooperative Awareness Message) en approche du péage. Cela améliorera les informations de géolocalisation déjà présentes. Notre objectif est d’arriver à une précision de moins d’un mètre pour distinguer 2 véhicules adjacents. D’autre part, le protocole de sécurité proposé permet d’assurer l’authentification des équipements participant à l’échange et à la validation de la transaction, l’intégrité des données échangées ainsi que la confidentialité des échanges compte tenu du contexte de communication sans-fil et de la sensibilité des données échangées. Une preuve de concept de la solution de télépéage utilisant la technologie ITS-G5 est développée et intègre nos deux contributions. / The precise localization of vehicles and the security of communication are requirements that make almost of the services provided in intelligent transport systems (ITS) more reliable. In recent years, they have been the subject of numerous research projects for various fields of application. In this thesis, the context is the development of an electronic toll service using the ITS-G5 technology. This wireless communication technology initially allows the sharing of traffic safety information between vehicles (V2V), vehicle and infrastructure (V2I). In our work, we propose a tolling application using equipment operating in ITS-G5 embedded in the connected vehicles and roadside units. For this, ensuring both precise geolocation of the vehicles and security of communication are required to validate the transaction.In order to properly locate the vehicles during the toll crossing, our approach is based on the understanding of the kinematics of the vehicle through a suitable modeling from the data collected in the cooperative messages (called CAM: Cooperative Awareness Message). This approach aims to improve the geolocation information already present in the message. Our goal is to achieve vehicle localization with an accuracy lower than one meter to distinguish two adjacent vehicles. On the other hand, the proposed tolling protocol ensures the authentication of the equipment or entities involved in the exchange and the validation of the transaction, the integrity of the transmitted data as well as the confidentiality of the communication. In this way, we take into account the context of the wireless communication and the sensitivity of the exchanged data. Our two contributions are integrated in the implemented Proof of Concept of the tolling application using the ITS-G5 technology.
66

Contraintes temporelles dans les bases de données de capteurs sans fil / Temporal constraints in wireless sensor databases

Belfkih, Abderrahmen 17 October 2016 (has links)
Dans ce travail, nous nous focalisons sur l’ajout de contraintes temporelles dans les Bases de Données de Capteurs Sans Fil (BDCSF). La cohérence temporelle d’une BDCSF doit être assurée en respectant les contraintes temporelles des transactions et la validité temporelle des données, pour que les données prélevées par les capteurs reflètent fidèlement l’état réel de l’environnement. Cependant, les retards de transmission et/ou de réception pendant la collecte des données peuvent conduire au non-respect de la validité temporelle des données. Une solution de type bases de données s'avère la plus adéquate. Il faudrait pour cela faire coïncider les aspects BD traditionnelles avec les capteurs et leur environnement. À cette fin, les capteurs déployés au sein d'un réseau sans fils sont considérés comme une table d'une base de données distribuée, à laquelle sont appliquées des transactions (interrogations, mises à jour, etc.). Les transactions sur une BD de capteurs nécessitent des modifications pour prendre en compte l'aspect continu des données et l'aspect temps réel. Les travaux réalisés dans cette thèse portent principalement sur trois contributions : (i) une étude comparative des propriétés temporelles entre une collecte périodique des données avec une base de données classique et une approche de traitement des requêtes avec une BDCSF, (ii) la proposition d’un modèle de traitement des requêtes temps réel, (iii) la mise en œuvre d’une BDCSF temps réel, basée sur les techniques décrites dans la deuxième contribution. / In this thesis, we are interested in adding real-time constraints in the Wireless Sensor Networks Database (WSNDB). Temporal consistency in WSNDB must be ensured by respecting the transaction deadlines and data temporal validity, so that sensor data reflect the current state of the environment. However, delays of transmission and/or reception in a data collection process can lead to not respect the data temporal validity. A database solution is most appropriate, which should coincide with the traditional database aspects with sensors and their environment. For this purpose, the sensor in WSN is considered as a table in a distributed database, which applied transactions (queries, updates, etc.). Transactions in a WSNDB require modifications to take into account of the continuous datastream and real-time aspects. Our contribution in this thesis focus on three parts: (i) a comparative study of temporal properties between a periodic data collection based on a remote database and query processing approach with WSNDB, (ii) the proposition of a real-time query processing model, (iii) the implementation of a real time WSNDB, based on the techniques described in the second contribution.
67

An evaluation of Intelligent Transport System: A case study of the Bus Rapid Transit (BRT) Rea-Vaya in Johannesburg, South Africa

Khwathisi, Ntsieni Colin 18 September 2017 (has links)
MURP / Department of Urban and Regional Planning / This study focuses on the evaluation of intelligent transport systems making use of the BRT-Rea-vaya in Johannesburg as a case study. This study was motivated by the observation that few studies have been conducted in the study area that tackle explicitly intelligent transport systems evaluation. Intelligent transport systems can assist in improving private and public transportation systems and operations performance. In the public sector where various modes of transport such as the taxi, metro bus, metro rail, Gautrain and the BRT Rea-vaya operates, intelligent transport systems present opportunities for improving Level of Service (LOS) delivery. In Johannesburg, the BRT Rea vaya system was adopted by the Johannesburg metropolitan municipality to provide a safe, reliable, efficient and accessible public transport system. The BRT Rea vaya system is aimed at providing a better public transport, operating systems and service. For the BRT Rea vaya systems to achieve its primary goals and objectives, an intelligent transport system was incorporated to better manage the BRT Rea-vaya systems operations and activities. The study disclosed the status quo, opinions and attitudes of commuters regarding their experiences with the BRT Rea vaya public transport systems in Johannesburg. Furthermore, the study investigated whether the original objectives and aims of intelligent transport system in the BRT Rea-vaya have been meet. A central theme of the investigation is seeking to understand constraints and opportunities regarding BRT Rea-vaya intelligent transport systems‘ operations and activities in Johannesburg. The use of primary and secondary data such as questionnaires, key informant interviews, observation, journals and previous researches related to intelligent transport systems were used to acquire an in-depth understanding of the operational management of BRT Rea-vaya intelligent transport system. Collected data was analyzed using Statistical Package for Social Sciences (SPSS) with the aid of Microsoft Excel making use of descriptive statistics, regression analysis, cross tabulation and chi-square test. This was presented using tables, graphs, maps etc. Qualitative data was analyzed making use of a thematic approach. The study resonates in the need for rapid public transport systems to provide lessons for improving and adopting intelligent transport systems. As an end product, the research provided a framework of analysis on how to integrate intelligent transport systems in the context of Bus rapid transit systems.
68

Leveraging technology for business fleet applications : a case study of fleet management system implemented in Kenya Power & Lighting Company Limited

Waiyaki, Edward Chege 18 October 2013 (has links)
This study aimed to evaluate the effectiveness of a modern fleet management system in improving the logistics of transporting staff, goods and materials in Kenya Power & Lighting Company, a utility firm in power distribution. In today’s competitive marketplace which is characterised by rapidly changing business requirements, leveraging leading edge technologies and adopting best practices are essential in order to ensure sound logistical support that guarantees both effectiveness and efficiency in the transportation processes. The sampling procedure of one-stage, cluster sampling and the use of the simple random sampling technique were used in this study to select a sample size which was sufficiently representative of the whole population. Both the descriptive study approach and the survey research strategy were adopted to enable the collection of data in a manner that allowed in-depth examination while gathering information that explained the relationships between constructs, in particular, cause and effect relationships. The main purpose of this dissertation was therefore to establish that the use of information technology is feasible in transport industries, explain possible obstacles and also any major advantages of its implementation. Secondly, as regards the theoretical aspect, a broadened view on the use of online tracking for vehicles using a global positioning system is presented, together with practical examples, to illustrate its successful implementation in a fleet management system. The study concludes by offering suggestions and recommendations from the research results and the researcher’s experiences for future studies. / Transport Economics, Logistics & Tourism / M. Com. (Transport Economics)
69

Performance Evaluation of Public Bus Transport Operations in Karnataka by using Non-parametric and Multivariate Analysis

Mulangi, Raviraj H January 2014 (has links) (PDF)
Indian cities rely predominantly on buses for public transport. The issues of performance measurement and efficiency analyses for the bus company have been gaining significance due to severe operating conditions and financial constraints in which these bus companies provide the service. Performance is defined as the levels of success of the service with respect to different parameters such as quality of service, cost effectiveness and safety. Performance is measured in terms of operational efficiency and financial efficiency. Operational Efficiency of an organization is the ability to utilize its available resources to the maximum extent. Financial Efficiency is a measure of the organization’s ability to translate its financial resources into revenue. Public bus transportation plays a pivotal role in India in bringing about greater mobility both within and between urban and rural areas. Through increased mobility, road transport also contributes immensely to social and economic development of different regions of the country. Public transport is provided by surface road transport using buses by the State Road Transport Undertakings (SRTUs) and by private operators. In this thesis, scientific analysis of the performance of SRTUs is carried out at different levels considering physical and financial parameters through multivariate techniques, non-parametric techniques and qualitative techniques. A comprehensive study on all the SRTUs of Karnataka at depot, division level are done and determined which quantitative method is suited for depot level and division level studies. From quantitative and qualitative studies of SRTUs strategies are developed and recommendations are made to improve the performance of SRTUs. Further, in addition to Bangalore metropolitan transport corporation (BMTC) performance analyses, the routes are analyzed to reduce the dead kilometer. Major contributions from this work: 1. Both inter and intra city operations of the public transport corporation in the state of Karnataka have been exhaustively analysed using operational and financial parameters. 2. Large amount of data over a long period has been collated from State road transport units and a standard format has been developed for collecting both operational and financial parameters for SRTU’s. 3. A generic framework and plan for performance evaluation of SRTU’s has been developed using ratio and benchmarking analysis, and, non-parametric and multivariate techniques like DEA (constant return to scale (CRS) and variable return to scale (VRS)), DEA-principal component analysis (PCA), DEA- bootstrapping. These analyses have been carried out at different levels, like transport corporations level (KSRTC NEKRTC, NWKRTC, BMTC), division level (33 divisions), and Depot level (193 depots). 4. Non parametric and multivariate Models have been developed and validated using DEAP and GAMS software before embarking on the above detailed analyses. 5. Analytical hierarchy approach (AHP), which is multi criteria structured technique, has been adopted to evaluate and analyze performance of the SRTU’s, divisions and depots based on qualitative and quantitative data. 6. User and operator perception studies of different SRTU’s of Karnataka have been done to evaluate the performance of these corporations from qualitative techniques. 7. From these comprehensive non parametric techniques, the efficiency of the SRTU’s have been evaluated and found that KSRTC has been the best operating unit among the SRTU’s considered for the study. The same has been observed from the AHP as well as perception surveys carried out as part of this thesis. 8. Operation and financial performance including profitability studies of Mysore urban transportation (Mysore city transport division) has been carried out before and after implementation of intelligent transport system (ITS). 9. The dead kilometer minimization model was formulated, which is a mixed integer programming problem, to get the optimal solution considering the capacity of the depot and time period of operation for the chosen network. An optimization technique has been developed for solving the dead kilometer problem in the operations of BMTC buses for the Volvo division (division operates 794 schedules). The alternative depot locations have been identified to reduce the dead kilometer, leading to large amount of savings for the corporation. 10. From the detailed analyses using non parametric techniques, multivariate and multi-criteria techniques along with perception surveys, strategies and recommendations have been arrived at to improve performance of the public transport corporations. This thesis consists of nine chapters and they are as below; Chapter 1 provides a brief introduction of public bus transport systems in India, their problems and need for performance evaluation of SRTUs. The impacts study of Mysore ITS, dead kilometer minimization problem for BMTC along with evaluating the performance of SRTUs by quantitative and qualitative data. This chapter provides the objective of the work and scope of the work. The main objectives of this research are 1. To develop a generic framework and plan for evaluation by identifying the performance indicators and data sources for evaluation.
70

Leveraging technology for business fleet applications : a case study of fleet management system implemented in Kenya Power & Lighting Company Limited

Waiyaki, Edward Chege 06 1900 (has links)
This study aimed to evaluate the effectiveness of a modern fleet management system in improving the logistics of transporting staff, goods and materials in Kenya Power & Lighting Company, a utility firm in power distribution. In today’s competitive marketplace which is characterised by rapidly changing business requirements, leveraging leading edge technologies and adopting best practices are essential in order to ensure sound logistical support that guarantees both effectiveness and efficiency in the transportation processes. The sampling procedure of one-stage, cluster sampling and the use of the simple random sampling technique were used in this study to select a sample size which was sufficiently representative of the whole population. Both the descriptive study approach and the survey research strategy were adopted to enable the collection of data in a manner that allowed in-depth examination while gathering information that explained the relationships between constructs, in particular, cause and effect relationships. The main purpose of this dissertation was therefore to establish that the use of information technology is feasible in transport industries, explain possible obstacles and also any major advantages of its implementation. Secondly, as regards the theoretical aspect, a broadened view on the use of online tracking for vehicles using a global positioning system is presented, together with practical examples, to illustrate its successful implementation in a fleet management system. The study concludes by offering suggestions and recommendations from the research results and the researcher’s experiences for future studies. / Transport Economics, Logistics and Tourism / M. Com. (Transport Economics)

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