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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.
41

The Fleet-Sizing-and-Allocation Problem: Models and Solution Approaches

El-Ashry, Moustafa 26 November 2007 (has links) (PDF)
Transportation is one of the most vital services in modern society. It makes most of the other functions of society possible. Real transportation systems are so large and complex that in order to build the science of transportation systems it will be necessary to work in many areas, such as: Modeling, Optimization and Simulation. We are interested in solutions for the so-called fleet-sizing-and-allocation problem (FSAP). Fleet sizing and allocation problems are one of the most interesting and hard to solve logistic problems. A fleet sizing and allocation problem consists of two interdependent parts. The fleet sizing problem is to determine a number of transportation units that optimally balances service requirements against the cost of purchasing and maintaining the transportation units. The allocation problem is dealing with the repositioning of transportation units to serve future transportation demand. To make the fleet sizing and allocation problem a little bit more tractable we concentrate on logistic systems with a special hub-and-spoke structure. We start with a very simple fleet sizing of one-to-one case. This case will cause us to focus attention on several key issues in fleet sizing. Afterwards, the generalization of the one-to-one system is the one-to-many system. As a simple example can serve the continuous time situation where a single origin delivers items to many destinations. For the case that items are produced in a deterministic production cycle and transportation times are stochastic. We also studied a hub-and-spoke problem with continuous time and stochastic demand. To solve this problem, based on Marginal Analysis, we applied queueing theory methods. The investigation of the fleet-sizing-and-allocation problem for hub-and-spoke systems is started for a single-period, deterministic-demand model. In that the model hub has to decide how to use a given number of TU’s to satisfy a known (deterministic) demand in the spokes. We consider two cases: 1. Renting of additional TU’s from outside the system is not possible, 2. Renting of additional TU’s from outside the system is possible. For each case, based on Marginal Analysis, we developed a simple algorithm, which gives us the cost-minimal allocation. Since the multi-period, deterministic demand problem is NP-hard we suggest to use Genetic Algorithms. Some building elements for these are described. For the most general situation we also suggest to use simulation optimization. To realize the simulation optimization approach we could use the software tool “Calculation Assessment Optimization System” (CAOS). The idea of CAOS is to provide a software system, which separates the optimization process from the optimization problem. To solve an optimization problem the user of CAOS has to build up a model of the system to which the problem is related. Furthermore he has to define the decision parameters and their domain. Finally, we used CAOS for two classes of hub-and-spoke system: 1. A single hub with four spokes, 2. A single hub with fifty spokes. We applied four optimizers – a Genetic Algorithm, Tabu Search, Hybrid Parallel and Hybrid Serial with two distributions (Normal Distribution and Exponential Distribution) for a customer interarrival times and their demand.
42

Light a Spark! Addressing Barriers and Enablers to Increase Demand of Electric Vehicles in Southeast Sweden

Nordström, Lina, Runesson, Lars, Warnecke, Helena January 2015 (has links)
The Personal Transportation System safeguards peoples’ cultural understanding of freedom: to move individually without being dependent on others. However, the increasing number of private vehicles driven on fossil fuels contributes to unsustainability and one of the most urgent issues, climate change. The authors explored electric vehicles as an alternative to fossil fuel driven vehicles as a way of moving strategically towards sustainability in the Personal Transportation System. In order to increase demand of electric vehicles, barriers need to be overcome. The authors identified perceived barriers and enablers through literature review, interviews with automobile dealers and other stakeholders of the EV sector in Southeast Sweden, as well as through an electronic survey of individuals living in this region. The outcome of the thesis is a pilot strategy using behavior change tools from Community-Based Social Marketing in order to address the perceived barriers and enablers on the demand side of the electric vehicle market. With highly positive attitudes towards electric vehicles in Southeast Sweden, the strategy may be successful in the region; however, it needs to be combined with further measures on the supply side of the market which cannot be addressed with behavior change tools.
43

Seismic risk assessment of the transportation network of Charleston, SC

Nilsson, Emily Michelle 01 April 2008 (has links)
The functionality of the transportation network following an earthquake event is critical for post-earthquake response and long-term recovery. The likely performance of a transportation network can be evaluated through a detailed seismic risk assessment. This paper presents an assessment of the seismic risk to the transportation network in the City of Charleston and the surrounding counties to support emergency response and the development of mitigation strategies and emergency planning efforts (such as lifeline selections). This study includes an inventory analysis of the 375 bridges in the Charleston area, and convolution of the seismic hazard with fragility curves analytically derived for classes of bridges common to this part of the country, damage-functionality relationships, and replacement cost estimates using relevant region-specific data. Using state-of-the-art tools, the distribution of potential bridge damage and functionality is evaluated for several scenario events, in order to aid in the identification of emergency routes and assess areas for investment in retrofit. Additionally, a sensitivity study is conducted to determine the criticality of a few of the different input models. Initial estimates of economic losses are assessed and preliminary recommendations for prioritizing retrofit are presented.
44

Passenger-focused Scheduled Transportation Systems: from Increased Observability to Shared Mobility

January 2018 (has links)
abstract: Recently, automation, shared use, and electrification are proposed and viewed as the “three revolutions” in the future transportation sector to significantly relieve traffic congestion, reduce pollutant emissions, and increase transportation system sustainability. Motivated by the three revolutions, this research targets on the passenger-focused scheduled transportation systems, where (1) the public transit systems provide high-quality ridesharing schedules/services and (2) the upcoming optimal activity planning systems offer the best vehicle routing and assignment for household daily scheduled activities. The high quality of system observability is the fundamental guarantee for accurately predicting and controlling the system. The rich information from the emerging heterogeneous data sources is making it possible. This research proposes a modeling framework to systemically account for the multi-source sensor information in urban transit systems to quantify the estimated state uncertainty. A system of linear equations and inequalities is proposed to generate the information space. Also, the observation errors are further considered by a least square model. Then, a number of projection functions are introduced to match the relation between the unique information space and different system states, and its corresponding state estimate uncertainties are further quantified by calculating its maximum state range. In addition to optimizing daily operations, the continuing advances in information technology provide precious individual travel behavior data and trip information for operational planning in transit systems. This research also proposes a new alternative modeling framework to systemically account for boundedly rational decision rules of travelers in a dynamic transit service network with tight capacity constraints. An agent-based single-level integer linear formulation is proposed and can be effectively by the Lagrangian decomposition. The recently emerging trend of self-driving vehicles and information sharing technologies starts creating a revolutionary paradigm shift for traveler mobility applications. By considering a deterministic traveler decision making framework, this research addresses the challenges of how to optimally schedule household members’ daily scheduled activities under the complex household-level activity constraints by proposing a set of integer linear programming models. Meanwhile, in the microscopic car-following level, the trajectory optimization of autonomous vehicles is also studied by proposing a binary integer programming model. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2018
45

Uma análise da estrutura do fluxo de informações na gestão operacional do transporte aquaviário de carga de Manaus usando a abordagem de análise de redes sociais

Cunha, Remo Lima 24 September 2015 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-08-01T13:40:05Z No. of bitstreams: 1 Dissertação - Remo Lima Cunha.pdf: 2042826 bytes, checksum: 6fc46595dd3c036c653673b1e6462e8b (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-08-01T13:40:48Z (GMT) No. of bitstreams: 1 Dissertação - Remo Lima Cunha.pdf: 2042826 bytes, checksum: 6fc46595dd3c036c653673b1e6462e8b (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-08-01T13:41:22Z (GMT) No. of bitstreams: 1 Dissertação - Remo Lima Cunha.pdf: 2042826 bytes, checksum: 6fc46595dd3c036c653673b1e6462e8b (MD5) / Made available in DSpace on 2016-08-01T13:41:22Z (GMT). No. of bitstreams: 1 Dissertação - Remo Lima Cunha.pdf: 2042826 bytes, checksum: 6fc46595dd3c036c653673b1e6462e8b (MD5) Previous issue date: 2015-09-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Social network analysis has grown every day, which finds application in almost every field of knowledge and particularly in information science. It is seen that the organizations survival status rely heavily on their ability to add value for stakeholders. The companies management methods proposed to determine objectives, information management, planning, and execution of strategies. This study aimed to analyze the structure of the flow of information in the operational management of water transport Manaus load using the analysis approach of social networks through Soft UCINET 6.4. The method that this research used to answer the research questions was the survey or evaluation research and had quantitative character and exploratory. The results were achieved, the network is designed and calculated its structural measures - indicators showing the dynamic flow of information in relational process between its actors. / A análise de redes sociais tem crescido a cada dia, onde encontra aplicação em quase todas as áreas do conhecimento e particularmente na ciência da informação. É perceptível que as organizações no estado de sobrevivência dependem muito de sua capacidade de agregar valor para as partes interessadas. Os métodos de administração das empresas propõe a determinação de objetivos, gerenciamento da informação, planejamento, e execução das estratégias. Assim, este estudo teve como objetivo analisar a estrutura do fluxo de informações na gestão operacional do transporte aquaviário de carga de Manaus usando a abordagem de Análise de Redes Sociais por meio do Soft UCINET 6.5. O método que esta pesquisa utilizou para responder as perguntas de pesquisas foi a Survey ou Pesquisa de Avaliação e teve caráter quantitativo e tipo exploratório. Os resultados foram alcançados, a rede foi desenhada e calculada suas medidas estruturais - indicadores, mostrando a dinâmica do fluxo de informações no processo relacional entre seus atores.
46

En flerkärnig framtid till mötes? : En utvärdering av Stockholmsregionens mål om flerkärnig utveckling

Haavisto, Jussi, Tillander, Sofi January 2016 (has links)
This study evaluates the Stockholm metropolitan region’s goal of becoming a sustainable polycentric region in order to meet the needs of a steadily growing population. By conducting interviews with regional planners, this study aims to shed light upon how polycentric development is affected by the design of the transportation network as well as what challenges planners face when planning for a polycentric region. The results from the interviews are then compared with an extensive literature study, covering both classic and contemporary regional planning theory. In addition, a GIS-analysis is conducted to measure urban intensities within the communities selected for polycentric development. The results show that Stockholm should pay more attention to those settlements located further away from the original city centre, thus making them more attractive for transit oriented development (TOD). / Denna studie är en utvärdering av Stockholmsregionens mål om flerkärnig utveckling för att möta regionens växande folkmängd. Genom intervjuer med regionala planerare ämnar denna studie ta reda på hur flerkärnig utveckling påverkas av trafiksystemets utformning samt vilka utmaningar regionala planerare ställs inför vid planering av en flerkärnig region. Intervjuresultaten jämförs därefter med såväl klassiska som moderna teorier om regional planering. Utöver detta genomförs en GIS-analys för att mäta urbana intensiteter inom de orter som valts ut för regionens flerkärniga utveckling. Resultatet visar att Stockholm borde fokusera på de orter belägna längst ifrån den ursprungliga stadskärnan för att göra dessa mer attraktiva för kollektivtrafiknära förtätning.
47

The impact on fuel costs when optimizing speed and weight in a single truck transportation system. / Påverkan på bränslekostnad vid optimering av hastighet och vikt i ett transportsystem för en lastbil.

Saxman, Tim January 2017 (has links)
Traditionally, route planning in the transportation sector has only focused on minimizing the total distance driven when transporting goods or people. This is often done using software tools since planning the optimal route is a complex task that is hard to solve by hand. While driving the shortest distance possible is an effort towards lowering fuel costs, which is one of the largest operating costs for truck transportation companies, it is not necessarily the most fuel efficient route. Recently, research has emerged regarding fuel minimizing route planning in order to perform transport operations at the lowest fuel cost possible. One factor contributing to fuel consumption is vehicle speed, since high speed means high wind resistance. Fuel can therefore be conserved by driving at lower speeds. Though lower speeds means longer travelling time, meaning that if the route is disrupted, causing a delay, there is an increased risk that all tasks cannot be performed during the started working day. The purpose of this thesis is to determine how to plan fuel efficient routes in a transportation system prone to disruptions. It was conducted at Scania to further understand how their truck customers can increase profitability in their businesses by planning fuel efficient routes. The truck transportation business is under heavy pressure with low margins. It is therefore valuable to plan fuel efficient routes. The outcome of this thesis is two linear programming models for route planning that take truck capacity, customer demand and time windows for delivery into account. The first model can be used during planning to find a fuel efficient route in order to deliver to all customers to the lowest fuel cost possible. The model gives a route with predetermined average speeds between the customers, as well as arrival time at each customer. When appropriate, the truck is proposed to drive at a slightly decreased speed, to lower wind resistance and thereby fuel consumption. By also taking load weight into account, the route can be planned such that a heavy part of the load is delivered early, reducing the weight carried for the rest of the route. The proposed model accomplishes on average 6.3 % lower fuel cost, compared to the most commonly used route planning model, where the shortest total driving distance is sought. If something would happen that disrupts the route, it might be impossible to deliver all customers before the day ends. To handle those situations, a second model is proposed. Once the transport is delayed, the model will revise the initial route and propose a new route based on a cost of delaying a delivery. The goal is then to deliver as much as possible to the lowest possible cost. The new route will still consist of predetermined average speeds and arrival times. The proposed model is a tool for handling the complex task of recalculating routes once a disruption occurs. In summary, the first model provides support to plan a route that potentially lowers the operational costs for truck transportation companies. If the planned route is disrupted, the second model will revise it and give a new route with new speeds and arrival times. If possible, the revised route will still result in making all deliveries, otherwise the model will postpone the smallest deliveries to the next day. Together, the two models serve as a valuable support for truck transport companies that want to increase their profitability by lowering their operational costs. / Traditionellt har ruttplanering inom transportsektorn endast fokuserat på att minimera den totala körsträckan vid transport av gods eller människor. Detta görs ofta med hjälp av mjukvaruverktyg, eftersom optimal ruttplanering är en komplex uppgift som är svår att lösa för hand. Att köra den kortaste totalsträckan är ett sätt att sänka bränslekostnaderna, vilket är en av de största driftskostnaderna för lastbilstransportföretag, men det är inte nödvändigtvis den mest bränsleeffektiva rutten. Den senaste tiden har allt mer forskning bedrivits inom bränsleminimering för att kunna utföra transportuppdrag till lägsta möjliga bränslekostnad. En faktor som bidrar till bränsleförbrukningen är fordonets hastighet, eftersom hög hastighet innebär högt luftmotstånd. Bränsleförbrukningen kan därför minskas genom att köra i lägre hastigheter. Även om lägre hastigheter betyder längre körtid, vilket innebär att om rutten störs och lastbilen blir försenad, finns det en ökad risk att allt inte kan levereras under den påbörjade arbetsdagen. Syftet med detta arbete är att bestämma hur bränsleeffektiva rutter kan planeras i ett transportsystem benäget för störningar. Arbetet genomfördes på Scania för att förstå hur deras lastbilskunder kan öka lönsamheten i sina företag genom att planera bränsleeffektivare rutter. Lastbilstransportbranschen är under hög press med låga marginaler. Det är därför värdefullt för Scanias lastbilskunder att planera bränsleeffektiva rutter. Arbetet resulterade i två ruteplaneringsmodeller som tar hänsyn till lastkapacitet, kundbehov och tidsfönster för leverans. Den första modellen kan användas vid planering för att hitta en bränsleeffektiv rutt så att alla kunder levereras till lägsta möjliga bränslekostnad. Modellen ger en rutt med förbestämda genomsnittshastigheter mellan kunderna, såväl som ankomsttid hos varje kund. När det anses lämpligt föreslås något minskade hastigheter, för att minska luftmotståndet och därigenom bränsleförbrukningen. Genom att även ta hänsyn till vikt, kan rutten planeras så att en tung del av lasten levereras tidigt, vilket minskar den vikt som transporteras på resterande sträckor. Den föreslagna modellen uppnår i genomsnitt 6,3% lägre bränslekostnad jämfört med den vanligaste ruteplaneringsmodellen, som ger den kortaste totala körsträckan. Om något skulle hända som stör rutten kan det vara omöjligt att leverera alla kunder innan dagen slutar. För att hantera dessa situationer föreslås en andra modell. När transporten är försenad planerar modellen om den ursprungliga rutten och föreslår en ny rutt baserat på kostnaden för att skjuta upp en leverans. Målet är då att leverera så mycket som möjligt till lägsta möjliga kostnad. Den nya rutten består fortfarande av förbestämda medelhastigheter och ankomsttider. Genom att använda den föreslagna modellen tillhandahålls ett verktyg för att hantera den komplexa uppgiften att planera om rutten vid en störning. Sammanfattningsvis ger den första modellen stöd för att planera en rutt som potentiellt sänker driftskostnaderna för lastbilstransportföretag. Om den planerade rutten utsätts för en störning, föreslår den andra modellen en ny rutt med nya hastigheter och ankomsttider. Om det är möjligt innebär den nya rutten fortfarande att lastbilen levererar till alla kunder, om inte skjuts de minsta leveranserna upp till nästa dag. Tillsammans är de två modellerna ett värdefullt stöd för lastbilstransportföretag som vill öka lönsamheten genom att sänka sina driftskostnader.
48

Evaluation of bus depot’s environmental impact and recommendations for improvements by material optimisation and improved energy efficiency

Chen, Guojing, Paulsson, Jill January 2015 (has links)
The public transportation in Stockholm is expanding and in order to meet the new demand the amount of buses and depots will have to increase within the city. As a result, it is getting more important to evaluate and analyse the performance of bus depots in order to reduce its environmental impact. The aim of this work is to study the production and operational phase during a bus depot’s life cycle and introduce saving measures that can reduce the emission of carbon dioxide equivalents (CO2eq). This study is conducted in collaboration with Skanska and the depot chosen for this study is currently under construction and located in Charlottendal, Värmdö. A base model is created for the whole bus depot area and the environmental impact is evaluated regarding the activities and usage of materials during production and the energy usage during operation of the depot. The evaluation of the model is performed by using the calculation tools IDA ICE, Anavitor, SPIK and Excel, and the environmental impact is expressed in terms of emission of CO2eq during the lifetime of the depot, which is assumed to be 50 years.  In order to investigate how bus depots can be built to be more climate neutral and energy efficient, several saving measures are evaluated in four cases. The first two cases are focusing on optimising the usage of materials in the building process, by reducing the material groups with the highest environmental impact and considering green construction solutions. The other two cases are aiming towards enhancing the energy performance of the depot, by reducing the usage of energy according to BBR and deliberating an indoor parking place for the buses. The total emission of CO2eq from the base model is determined to be approximately 16 000 tonnes during the lifetime of the depot. About 42 percent of the environmental impact is instigated during the production phase and the rest of the emission is caused by the use of electricity and heat during operation. By considering the implemented measures it can be concluded that the largest reduction in emission can be obtained by optimising the usage of materials on the site, which is achieved by reducing two of the largest materials groups consisting of concrete and asphalt. By reducing the usage of these materials the total emission from the production phase can be reduced by approximately 9 percent and the total emissions can be reduced by up to 4 percent.  To verify the obtained results a sensitivity analysis is performed where three important parameters are investigated. The chosen parameters are; the assumption of the emission factors for the electricity and district heating mixes and the required heating demand for the buses. According to the sensitivity analysis the final results are highly related to the considered parameters. For instance, if the delivered district heating is assumed to be supplied by Fortum, which is the main distributor within Stockholm, it can be concluded that an indoor parking place for the buses is the most beneficial solution to reduce the total emissions. By building a new base hall the emissions instigated from the total heating demand can be reduced by 55 percent and the total emissions can be reduced by 25 percent. / Kollektivtrafiken i Stockholm genomgår i dagsläget en utbyggnation och för att möta det ökade behovet på transportmedel så måste antalet bussar och bussdepåer att öka i området. På grund av detta blir det mer och mer viktigt att utvärdera och analysera bussdepåernas prestanda för att kunna minska miljöpåverkan från dessa verksamheter. Syftet med detta arbete är att studera produktion- och driftfasen under en bussdepås livscykel samt presentera åtgärder som kan leda till en minskning i utsläppen av koldioxidekvivalenter (CO2ekv). Detta arbete utförs i sammarbete med Skanska och den studerade bussdepån, som ligger i Charlottendal på Värmdö, är för tillfället under konstruktion. För att kunna utvärdera den valda depån skapas en basmodell där klimatpåverkan utvärderas utifrån de aktiviteter och material som används i produktionsfasen och den energi som används under driften av depån. De beräkningsverktyg som har används i utvärderingen av depån består av IDA ICE, Anavitor, SPIK och Excel, och klimatpåverkan från depån uttrycks i ton CO2ekv under dess livslängd, vilken har antagits till 50 år. För att undersöka hur depåer kan konstrueras för att vara mer klimatneutrala och energieffektiva så utvärderas olika besparingsåtgärder i fyra fall. Fokus för de två första fallen ligger på att optimera materialanvändningen i byggprocessen, vilket inkluderar en minskning av de material som genererar i de största utsläppen samt en analys av mer miljövänliga konstruktionslösningar. De andra två fallen riktas istället mot att förbättra energiprestandan av depån genom att minska energianvändningen enligt BBR och överväga en inomhusparkering för bussarna.  De totala utsläppen från basmodellen utgör cirka 16 000 ton, där 42 procent orsakas under produktionsfasen och de resterande utsläppen kommer från driften av depån. Utifrån analysen kan man dra slutsatsen att den största minskningen av utsläpp kan åstadkommas genom att dra ner på mängden betong och asfalt i produktionsfasen. Genom att minska på dessa material kan utsläppen från produktionsfasen minskas med ungefär 9 procent och de totala utsläppen kan minskas med 4 procent. I känslighetsanalysen undersöks tre huvudsakliga parametrar som har en stor inverkan på det slutliga resultatet av beräkningarna. Dessa parametrar består av de valda energimixerna för elektricitet och fjärrvärme samt värmebehovet för bussarna. Enligt resultatet i känslighetsanalysen så är en inomhusparkering den förbättringsåtgärd som leder till den största minskningen av utsläpp. Detta resultat fås då fjärrvärmen antas levereras av Fortum, som är den största leverantören i Stockholmsområdet. Genom att investera i en ny busshall kan det totala värmebehovet för bussdepån minskas med 55 procent och det totala utsläppet med 25 procent.
49

Secure Localization Topology and Methodology for a Dedicated Automated Highway System

Deka, Bhaswati 01 May 2013 (has links)
Localization of nodes is an important aspect in a vehicular ad-hoc network (VANET). Research has been done on various localization methods. Some are more apt for a specific purpose than others. To begin with, we give an overview of a vehicular ad-hoc network, localization methods, and how they can be classified. The distance bounding and verifiable trilateration methods are explained further with their corresponding algorithms and steps used for localization. Distance bounding is a range-based distance estimation algorithm. Verifiable trilateration is a popular geometric method of localization. A dedicated automated highway infrastructure can use distance bounding and/or trilateration to localize an automated vehicle on the highway. We describe a highway infrastructure for our analysis and test how well each of the methods performs, according to a security measure defined as spoofing probability. The spoofing probability is, simply put, the probability that a given point on the highway will be successfully spoofed by an attacker that is located at any random position along the highway. Spoofing probability depends on different quantities depending on the method of localization used. We compare the distance bounding and trilateration methods to a novel method using friendly jamming for localization. Friendly jamming works by creating an interference around the region whenever communication takes place between a vehicle and a verifier (belonging to the highway infrastructure, which is involved in the localization process using a given algorithm and localization method). In case of friendly jamming, the spoofing probability depends both on the position and velocity of the attacker and those of the target vehicle (which the attacker aims to spoof). This makes the spoofing probability much less for friendly jamming. On the other hand, the distance bounding and trilateration methods have spoofing probabilities depending only on their position. The results are summarized at the end of the last chapter to give an idea about how the three localization methods, i.e. distance bounding, verifiable trilateration, and friendly jamming, compare against each other for a dedicated automated highway infrastructure. We observe that the spoofing probability of the friendly jamming infrastructure is less than 2% while the spoofing probabilities of distance bounding and trilateration are 25% and 11%, respectively. This means that the friendly jamming method is more secure for the corresponding automated transportation system (ATS) infrastructure than distance bounding and trilateration. However, one drawback of friendly jamming is that it has a high standard deviation because the range of positions that are most vulnerable is high. Even though the spoofing probability is much less, the friendly jamming method is vulnerable to an attack over a large range of distances along the highway. This can be overcome by defining a more robust infrastructure and using the infrastructure's resources judiciously. This can be the future scope of our research. Infrastructures that use the radio resources in a cost effective manner to reduce the vulnerability of the friendly jamming method are a promising choice for the localization of vehicles on an ATS highway.
50

Safety and Security in AutonomousVehicles : A Systematic Literature Review

Soltaninejad, Amirhossein, Rashidfarokhi, Mohammad Ali January 2023 (has links)
A transformative revolution in transportation is coming with the advent of Au-tonomous Vehicles (AVs), which are expected to increase mobility, reduce trafficcongestion, and save fuel. Although AVs present significant advantages, they alsopose substantial challenges, particularly when it comes to security and safety. Theaim of this study is to map out the existing knowledge in order to facilitate furtherresearch and development, which will hasten the rollout of secure and reliable au-tonomous vehicles. This, in turn, will enable a sustainable and efficient future fortransportation. Research on AV safety and security is reviewed in this thesis in acomprehensive systematic literature review. The search process identified a total of283 studies published between 2019 and 2022, out of which 24 studies were selectedthrough a multi-stage process according to our predefined protocol. Based on re-search topics in selected studies, our findings have a significant impact on the fieldof Artificial Intelligence and automated vehicles. Based on our findings, we canprovide a summary of current knowledge regarding the safety, security, and stabilityimplications of autonomous vehicles. Simulations, real-life experiments, and physi-cal tests were all used in the selected articles for evaluation. Aside from the excellentresults, we identified many limitations of the articles, including the limitations of thedata sets, the analysis of unusual events, and the verification practices.

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