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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.
151

Leveraging Vehicle-to-Infrastructure Communications for Adaptive Traffic Signaling and Better Energy Utilization

Agrawal, Manas 30 August 2013 (has links)
No description available.
152

[en] MEANINGS ATTACHED TO MARITIME CRISES: A MULTI-METHOD STUDY / [pt] SIGNIFICADOS ATRIBUÍDOS A CRUZEIROS MARÍTIMOS: UM ESTUDO MULTIMÉTODOS

ANA RAQUEL COELHO ROCHA 14 September 2015 (has links)
[pt] Esta tese de doutorado investiga aspectos relacionados à participação em cruzeiros marítimos por consumidores emergentes, pertencentes à chamada nova classe média brasileira . O arcabouço teórico do estudo está vinculado à corrente teórica denominada CCT – Consumer Culture Theory, ancorando-se particularmente no modelo conceitual proposto por McCracken (1986) sobre a transferência de significados do mundo culturalmente constituído para o consumidor e nas metáforas de consumo propostas por Holt (1995). Partiu-se do entendimento de que o consumo é essencialmente simbólico, uma vez que o consumidor atribui a bens e serviços significados que vão além do aspecto meramente utilitário. Buscou-se identificar a natureza dos significados atribuídos a cruzeiros marítimos por consumidores emergentes, assim como elementos do processo pelo qual se dá a transferência de significados do mundo culturalmente constituído para o consumidor. Adotou-se, assim, uma abordagem interpretativa, em que o que está em jogo não são os aspectos objetivos do consumo, mas a subjetividade inerente à percepção do consumidor em relação ao fenômeno pesquisado. A pesquisa desenvolveu-se por meio de combinação sistemática entre teoria e campo, seguindo a abordagem abdutiva proposta por Dubois e Gadde (2002). O estudo caracteriza-se ainda como pesquisa multimétodos, sendo constituído por três trabalhos empíricos que buscam entender o fenômeno investigado a partir de diferentes perspectivas. Os três estudos empíricos que compõem esta tese de doutorado são: (i) análise de conteúdo de anúncios de empresas que oferecem cruzeiros marítimos; (ii) grupos de foco com consumidores emergentes que ainda não haviam participado de um cruzeiro; e (iii) observação participante em cruzeiros marítimos posicionados para este segmento de consumidores. Por meio desses três estudos, buscou-se identificar a natureza simbólica dos cruzeiros marítimos para consumidores emergentes, tanto no que se refere à associação dos cruzeiros marítimos a significados atrelados ao produto por meio da propaganda das empresas organizadoras de cruzeiros, como aqueles que lhe são atribuídos pelos próprios consumidores. No primeiro estudo foram analisados 60 anúncios de empresas que oferecem cruzeiros marítimos, veiculados no semestre que antecedeu a temporada de cruzeiros 2011/2012, utilizando análise de conteúdo quantitativa e qualitativa. No segundo estudo, foram realizados quatro grupos de foco, com o propósito de entender o conteúdo simbólico presente no imaginário desse grupo, já que os consumidores que dele participaram não haviam tido ainda a experiência de consumo, embora tivessem a intenção de fazê-lo. Por fim, a observação participante foi realizada em dois cruzeiros. A primeira observação participante foi encoberta, ou seja, a pesquisadora conviveu com os participantes do cruzeiro sem revelar sua identidade, o que levou à realização de entrevistas em profundidade após o término do cruzeiro; a segunda foi aberta, tendo a pesquisadora revelado seu propósito durante o cruzeiro e realizado as entrevistas em profundidade ao longo do mesmo. Os métodos utilizados permitiram identificar tanto os significados veiculados pela propaganda das empresas ofertantes de cruzeiros marítimos, como aqueles que os consumidores associam ao consumo desse tipo de lazer. Verificou-se que a propaganda não surge como elemento principal no processo de transferência de significado para esses consumidores, sendo a difusão boca a boca mais importante, em função de sua credibilidade, além das imagens presentes no imaginário coletivo. Além de confirmar as metáforas de consumo propostas por Holt, o estudo identificou novas metáforas, em particular a de consumo como realização , em que os consumidores emergentes utilizam o consumo de cruzeiros como forma de evidenciar, para si mesmos e para os demais, sua ascensão social. / [en] This thesis investigates aspects related to participation in maritime cruises for emerging consumers belonging to the so called new Brazilian middle class. The theoretical framework of the study is linked to the theoretical trend called CCT - Consumer Culture Theory, anchoring particularly in the conceptual model proposed by McCracken (1986) on the transfer of meaning from the culturally constituted world to the consumer and the consumer metaphors proposed by Holt (1995). It started with the understanding that consumption is essentially symbolic, since consumers assign meanings to goods and services that go beyond the purely utilitarian aspect. It sought to identify the nature of the meanings assigned to cruises by emerging consumers, as well as elements of the process by which meanings are transferred from the culturally constituted world to the consumer. Thus, an interpretive approach was adopted, in which what is at stake is not the objective aspects of consumption, but the subjectivity inherent to the consumer s perception regarding the researched phenomenon. The research was developed through a systematic combination between theory and field, following the abductive approach proposed by Dubois and Gadde (2002). The three empirical studies that comprise this thesis are: (i) content analysis of advertisements from companies offering cruises; (ii) focus groups with emerging consumers who had not yet participated in a cruise; and (iii) participant observation in a cruise targeted at this consumer segment. Through these three studies, it sought to identify the symbolic nature of cruises to emerging consumers with regard to the association of such cruises to the meanings attached to products through the advertising of cruise organizer companies, as well as those meanings attributed to the cruise by the consumers themselves. In the first study 60 ads published by cruise companies were analyzed using quantitative and qualitative content analysis. These ads were published in the semester preceding the 2011/2012 cruise season. In the second study, four focus groups were conducted, with the purpose of understanding the symbolic content present in the imagination of this group, as consumers participating had not yet experienced of this type of consumption, although they intended to do so. Finally, the participant observation was carried out in two cruises. The first participant observation was covert, meaning that the researcher experienced the cruise with the participants without revealing her identity, which led to the realization of in-depth interviews after the cruise; the second participant observation was overt, the researcher revealed her purpose during the cruise, and in-depth interviews were conducted during the trip. The methods allowed for the identification of both the meanings conveyed by the advertisement of companies that offer cruises, and those that consumers associate to the consumption of this type of leisure. Results indicate that advertisements do not appear as the main element in the process of meaning transference for these consumers; word of mouth is the more important and credible information dissemination path, as well as the images present in the collective imagination. Besides confirming the metaphors of consumption proposed by Holt, the study identified new metaphors, in particular that of consumption as achievement, where emerging consumers use consumption of maritime cruises as a way to demonstrate to themselves and to others, their social advancement.
153

Evaluation and Implementation of a Longitudinal Control in a Platoon of Radio Controlled Vehicles

Roshanghias, Daniel January 2017 (has links)
Over the past decades, congestion and emission problems has increased remarkablywhich escalates the demands on vehicles. The advancements withinthe eld of information and communication systems gives the opportunity todeal with the aforementioned problems. The concept of platooning shows tobe an attractive way of reducing both congestion and emissions by having ashort inter-vehicle spacing. The ndings in studies show that fuel reductionpotentials of 5-20 % are viable as a result of the lowered air drag by drivingin platoon. This thesis investigates the state of the art within the areaof intelligent transport systems (ITS) along with advanced driver assistancesystems (ADAS). Furthermore, the prosecuted work results in a proposedcontrol design for a longitudinal control in a platoon of vehicles. The platoonconsists of two homogeneous radio controlled vehicles (RCV) which aremodelled by taking advantage of system identication methods. The identi-ed plant models are implemented into a Simulink model where the controlsystem is developed. Moreover, the developed control system is implementedinto a real-time demonstrator for experimental evaluation. The results showsthat the modelled dynamics corresponds reasonably well with the real dynamicsof the system. The developed control system proves to work well andagree with the expectations of its performance obtained from simulations.The performance of the proposed controller has been evaluated by means ofsimulations and real experiments. The resulting control system consists ofPID controllers for both speed and spacing control. / Under de senaste decennierna har mangden trakstockningar och problemmed utslapp okat - darmed aven kraven pa vara fordon. Samtidigt skaparframstegen inom informations- och kommunikationssystem mojligheter foratt hantera ovannamnda problem. Kolonnkorning, eller platooning har visatsig vara en eektiv metod for att minska saval trakstockningar som utslappsom en foljd av kortare avstand mellan fordon. Resultat fran studier visarhur en branslereduktion runt 5-20 % ar mojlig till foljd av det sankta luftmotstandet vid kolonnkorning. Avhandlingen undersoker teknikens standpunktinom intelligenta transportsystem (ITS) tillsammans med avancerade drivhjalpsystem(ADAS). Vidare resulterar arbetet i ett forslag till regleringsdesignfor en longitudinell kontroll i en kolonn av fordon. Kolonnen bestar av tvahomogena radiostyrda fordon (RCV) som modelleras genom att utnyttjametoder for systemidentiering. De identierade systemmodellerna implementerasi en Simulink-modell dar styrsystemet utvecklas. Dessutom implementerasdet utvecklade styrsystemet i en realtids-demonstration for experimentellutvardering. Resultaten visar att den modellerade dynamikenstammer bra overens med systemets verkliga dynamik. Det utvecklade styrsystemetvisar sig fungera bra och overensstammer med forvantningarna pa dessprestanda som erhallits genom simuleringar. Den foreslagna regulatorns prestandahar utvarderats med hjalp av simuleringar och verkliga experiment.Det resulterande styrsystemet bestar av PID regulatorer for bade hastighetsochavstandskontroll.
154

Extraction of Driving Modes for Dynamic Speed Adaptation in Curves / Extrahering av körlägen för dynamisk hastighetsanpassning i kurvor

Kanter, Claudia January 2017 (has links)
Modern cars have a multitude of driver assistance functions that aim to support the driver in his/her everyday driving. One part of this is the Adaptive Cruise Control (ACC) that aims to keep a driver-specified speed. However, this set speed might be perceived as too high for some curves and as a result the driver will interrupt the system and take control again. To avoid this, a Curve Speed Adaptation (CSA) system aims to adapt the speed for an upcoming curve. Such a system should aim to mimic a driver and take into consideration how the driver would behave if he/she were to drive. This work aims to find a set of so-called Driving Modes that can describe how drivers with different driving styles drive through curves with different road properties by analysing recorded manual driving. A nested clustering approach is tested to divide curves into groups based on the driving style they were driven at and their road properties. The results show that this approach is able to capture different driving behaviours through curves. The road type and speed limit of a curve seem thereby to have the main influence on the driving behaviour. Clustering curves first by their driving style followed by the road properties yields thereby the more distinguishable Driving Modes. However, further improvements of the clustering methods are necessary to improve the obtained Driving Modes. The results of this thesis can form the basis for the development of a Curve Speed Adaptation system that adjusts for both the individual driver as well as particular road properties to improve the driver's comfort. / Moderna bilar har en mängd förarstödsystemer som syftar till att stödja föraren i sin dagligakörning. En av dem är Adaptive Cruise Control (ACC) som syftar till att hålla en hastighetspecificerad av föraren. Men denna hastighet kan uppfattas som för hög för vissa kurvoroch som resultat tar föraren kontrollen igen själv. För att undvika detta ska ett Curve SpeedAdaptation (CSA) system anpassa hastigheten för en kommande kurva. Ett sådant systembör sträva efter att efterlikna en förare och ta hänsyn till hur föraren skulle köra själv. Dethär examensarbetet syftar till att hitta så kallade körlägen som kan beskriva hur förare medolika körstilar kör genom kurvor med olika omständigheter genom att analysera manuellakörningar. En nestad klustringsmetod testas för att dela upp kurvor i grupper baserat påkörstilen som de kördes på och deras vägegenskaper. Resultaten visar att denna metod kanfånga olika körningsbeteenden genom kurvor. Vägtypen och hastighetsbegränsningen fören kurva verkar därmed ha huvudinverkan på körbeteendet. Att dela kurvorna först efterderas körstil följt av vägegenskaper ger bättre körlägena. Men ytterligare förbättringar avklustringsmetoderna är nödvändig för att förbättra de erhållna körningsmetoderna. Resul-taten av detta examensarbetet kan utgöra grunden för utvecklingen av ett kurvhastighetsanpassningssystem som anpassar både för den enskilda föraren och speciella vägegenskaperför att förbättra förarens komfort.
155

Simulation Studies of Impact of Heavy-Duty Vehicle Platoons on Road Traffic and Fuel Consumption

Johansson, Ingrid January 2018 (has links)
The demand for road freight transport continues to grow with the growing economy, resulting in increased fossil fuel consumption and emissions. At the same time, the fossil fuel use needs to decrease substantially to counteract the ongoing global warming. One way to reduce fuel consumption is to utilize emerging intelligent transport system (ITS) technologies and introduce heavy-duty vehicle (HDV) platooning, i.e. HDVs driving with small inter-vehicle gaps enabled by the use of sensors and controllers. It is of importance for transport authorities and industries to investigate the effects of introducing HDV platooning. Previous studies have investigated the potential benefits, but the effects in real traffic, both for the platoons and for the surrounding vehicles, have barely been explored. To further utilize ITS and optimize the platoons, information about the traffic situation ahead can be used to optimize the vehicle trajectories for the platoons. Paper I presents a dynamic programming-based optimal speed control including information of the traffic situation ahead. The optimal control is applied to HDV platoons in a deceleration case and the potential fuel consumption reduction is evaluated by a microscopic traffic simulation study with HDV platoons driving in real traffic conditions. The effects for the surrounding traffic are also analysed. Paper II and Paper III present a simulation platform to assess the effects of HDV platooning in real traffic conditions. Through simulation studies, the potential fuel consumption reduction by adopting HDV platooning on a real highway stretch is evaluated, and the effects for the other vehicles in the network are investigated. / Efterfrågan på godstransporter på väg fortsätter att öka i takt med den växande ekonomin, vilket resulterar i ökad förbrukning av fossila bränslen och ökade utsläpp. Samtidigt behöver användandet av fossila bränslen minska för att motverka den pågående globala uppvärmningen. Ett sätt för att minska bränsleförbrukningen är att utnyttja den teknik kring intelligenta transportsystem som är under utveckling och introducera lastbilskonvojer, det vill säga lastbilar som använder sensorer och regulatorer för att kunna köra med korta avstånd mellan sig. För transportföretag och -myndigheter är det viktigt att undersöka effekterna av att införa lastbilskonvojkörning. Tidigare studier har undersökt de möjliga fördelarna, men effekterna vid körning i trafik, både för konvojerna och för omgivande fordon, är outforskade. För att ytterligare utnyttja intelligenta transportsystem och optimera konvojerna kan information om trafiksituationen längre fram på vägen användas för att optimera konvojernas körning. Artikel I presenterar en optimal hastighetsregulator baserad på dynamisk programmering och som inkluderar information om trafiksituationen längre fram. Den optimala regulatorn appliceras på lastbilskonvojer under ett inbromsningsscenario och den potentiella minskningen i bränsleförbrukning utvärderas genom en mikroskopisk trafiksimuleringsstudie där lastbilskonvojerna kör i verkliga trafikförhållanden. Effekterna för omgivande fordon är också analyserade.Artikel II och artikel III presenterar en simuleringsplattform för att utvärdera effekterna av lastbilskonvojkörning i verkliga trafikförhållanden. Genom simuleringsstudier analyseras den potentiella bränsleförbrukningsminskningen då lastbilskonvojer körs på en verklig motorvägssträcka och effekterna för de övriga fordonen på vägen undersöks. / <p>QC 20180516</p>
156

Stability of a Vision Based Platooning System

Köling, Ann, Kjellberg, Kristina January 2021 (has links)
The current development of autonomous vehiclesallow for several new applications to form and evolve. One ofthese are platooning, where several vehicles drive closely togetherwith automatic car following. The method of getting informationabout the other vehicles in a platoon can vary. One of thesemethods is using visual information from a camera. Having acamera on-board an autonomous vehicle has further potential, forexample for recognition of objects in the vehicle’s surroundings.This bachelor thesis uses small RC vehicles to test an example ofa vision based platooning system. The system is then evaluatedusing a step response, from which the stability of the systemis analyzed. Additionally, a previously developed communicationbased platooning system was tested in the same way and it’sstability compared. The main conclusion of this thesis is that it isfeasible to use a camera, ArUco marker and an Optimal VelocityRelative Velocity model to achieve a vision based platoon on asmall set of RC vehicles. / Forskningsframsteg inom området autonoma fordon möjliggör utveckling av ett flertal nya tillämpningar. En av dessa är platooning, som innebär att flera fordon kör nära varandra med automatisk farthållning. Metoden för att erhålla information om de andra fordonen i platoonen kan variera. En av dessa metoder är att använda visuell information från en kamera. Att ha en kamera ombord på ett autonomt fordon har stor potential, exempelvis för detektering av objekt i fordonets omgivning. Det här kandidatexamensarbetet använder små radiostyrda bilar för att testa ett exempel av ett kamerabaserat platooning-system. Systemet är sedan utvärderat med hjälp av ett stegsvar, från vilket stabiliteten av systemet är analyserat. Dessutom testas ett tidigare utvecklat kommunikationsbaserat platooning-system, hittills bara testat i simulering, på samma uppsättning bilar. Den huvudsakliga slutsatsen av detta arbete är att det är möjligt att använda en kamera, ArUco markör och en Optimal Velocity Relative Velocity modell för att uppnå kamerabaserad platoon med en liten uppsättning radiostyrda bilar. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm
157

Formal Modelling of Cruise Control System Using Event-B and Rodin Platform

Predut, S., Ipate, F., Gheorghe, Marian, Campean, Felician 28 June 2018 (has links)
no / Formal modelling is essential for precisely defining, understanding and reasoning when designing complex systems, such as cyberphysical systems. In this paper we present a formal specification using Event-B and Rodin platform for a case study of a cruise control system for a hybrid propulsion vehicle and electric bicycle (e-Bike). Our work uses the EventB method, a formal approach for reliable systems specification and verification, being supported by the Rodin platform, based on theorem proving, allowing a stepwise specification process based on refinement. We also use, from the same platform, the ProB model checker for the verification of the B-Machine and iUML plug-in to visualize our model. This approach shows the benefits of using a formal modelling platform, in the context of cyberphysical systems, which provides multiple ways of analysing a system. / Romanian National Authority for Scientific Research, CNCS-UEFISCDI, project number PN-III-P4-ID-PCE-20160210.
158

Optimal Control for Automotive Powertrain Applications

Reig Bernad, Alberto 07 November 2017 (has links)
Optimal Control (OC) is essentially a mathematical extremal problem. The procedure consists on the definition of a criterion to minimize (or maximize), some constraints that must be fulfilled and boundary conditions or disturbances affecting to the system behavior. The OC theory supplies methods to derive a control trajectory that minimizes (or maximizes) that criterion. This dissertation addresses the application of OC to automotive control problems at the powertrain level, with emphasis on the internal combustion engine. The necessary tools are an optimization method and a mathematical representation of the powertrain. Thus, the OC theory is reviewed with a quantitative analysis of the advantages and drawbacks of the three optimization methods available in literature: dynamic programming, Pontryagin minimum principle and direct methods. Implementation algorithms for these three methods are developed and described in detail. In addition to that, an experimentally validated dynamic powertrain model is developed, comprising longitudinal vehicle dynamics, electrical motor and battery models, and a mean value engine model. OC can be utilized for three different purposes: 1. Applied control, when all boundaries can be accurately defined. The engine control is addressed with this approach assuming that a the driving cycle is known in advance, translating into a large mathematical problem. Two specific cases are studied: the management of a dual-loop EGR system, and the full control of engine actuators, namely fueling rate, SOI, EGR and VGT settings. 2. Derivation of near-optimal control rules, to be used if some disturbances are unknown. In this context, cycle-specific engine calibrations calculation, and a stochastic feedback control for power-split management in hybrid vehicles are analyzed. 3. Use of OC trajectories as a benchmark or base line to improve the system design and efficiency with an objective criterion. OC is used to optimize the heat release law of a diesel engine and to size a hybrid powertrain with a further cost analysis. OC strategies have been applied experimentally in the works related to the internal combustion engine, showing significant improvements but non-negligible difficulties, which are analyzed and discussed. The methods developed in this dissertation are general and can be extended to other criteria if appropriate models are available. / El Control Óptimo (CO) es esencialmente un problema matemático de búsqueda de extremos, consistente en la definición de un criterio a minimizar (o maximizar), restricciones que deben satisfacerse y condiciones de contorno que afectan al sistema. La teoría de CO ofrece métodos para derivar una trayectoria de control que minimiza (o maximiza) ese criterio. Esta Tesis trata la aplicación del CO en automoción, y especialmente en el motor de combustión interna. Las herramientas necesarias son un método de optimización y una representación matemática de la planta motriz. Para ello, se realiza un análisis cuantitativo de las ventajas e inconvenientes de los tres métodos de optimización existentes en la literatura: programación dinámica, principio mínimo de Pontryagin y métodos directos. Se desarrollan y describen los algoritmos para implementar estos métodos así como un modelo de planta motriz, validado experimentalmente, que incluye la dinámica longitudinal del vehículo, modelos para el motor eléctrico y las baterías, y un modelo de motor de combustión de valores medios. El CO puede utilizarse para tres objetivos distintos: 1. Control aplicado, en caso de que las condiciones de contorno estén definidas. Puede aplicarse al control del motor de combustión para un ciclo de conducción dado, traduciéndose en un problema matemático de grandes dimensiones. Se estudian dos casos particulares: la gestión de un sistema de EGR de doble lazo, y el control completo del motor, en particular de las consignas de inyección, SOI, EGR y VGT. 2. Obtención de reglas de control cuasi-óptimas, aplicables en casos en los que no todas las perturbaciones se conocen. A este respecto, se analizan el cálculo de calibraciones de motor específicas para un ciclo, y la gestión energética de un vehículo híbrido mediante un control estocástico en bucle cerrado. 3. Empleo de trayectorias de CO como comparativa o referencia para tareas de diseño y mejora, ofreciendo un criterio objetivo. La ley de combustión así como el dimensionado de una planta motriz híbrida se optimizan mediante el uso de CO. Las estrategias de CO han sido aplicadas experimentalmente en los trabajos referentes al motor de combustión, poniendo de manifiesto sus ventajas sustanciales, pero también analizando dificultades y líneas de actuación para superarlas. Los métodos desarrollados en esta Tesis Doctoral son generales y aplicables a otros criterios si se dispone de los modelos adecuados. / El Control Òptim (CO) és essencialment un problema matemàtic de cerca d'extrems, que consisteix en la definició d'un criteri a minimitzar (o maximitzar), restriccions que es deuen satisfer i condicions de contorn que afecten el sistema. La teoria de CO ofereix mètodes per a derivar una trajectòria de control que minimitza (o maximitza) aquest criteri. Aquesta Tesi tracta l'aplicació del CO en automoció i especialment al motor de combustió interna. Les ferramentes necessàries són un mètode d'optimització i una representació matemàtica de la planta motriu. Per a això, es realitza una anàlisi quantitatiu dels avantatges i inconvenients dels tres mètodes d'optimització existents a la literatura: programació dinàmica, principi mínim de Pontryagin i mètodes directes. Es desenvolupen i descriuen els algoritmes per a implementar aquests mètodes així com un model de planta motriu, validat experimentalment, que inclou la dinàmica longitudinal del vehicle, models per al motor elèctric i les bateries, i un model de motor de combustió de valors mitjans. El CO es pot utilitzar per a tres objectius diferents: 1. Control aplicat, en cas que les condicions de contorn estiguen definides. Es pot aplicar al control del motor de combustió per a un cicle de conducció particular, traduint-se en un problema matemàtic de grans dimensions. S'estudien dos casos particulars: la gestió d'un sistema d'EGR de doble llaç, i el control complet del motor, particularment de les consignes d'injecció, SOI, EGR i VGT. 2. Obtenció de regles de control quasi-òptimes, aplicables als casos on no totes les pertorbacions són conegudes. A aquest respecte, s'analitzen el càlcul de calibratges específics de motor per a un cicle, i la gestió energètica d'un vehicle híbrid mitjançant un control estocàstic en bucle tancat. 3. Utilització de trajectòries de CO com comparativa o referència per a tasques de disseny i millora, oferint un criteri objectiu. La llei de combustió així com el dimensionament d'una planta motriu híbrida s'optimitzen mitjançant l'ús de CO. Les estratègies de CO han sigut aplicades experimentalment als treballs referents al motor de combustió, manifestant els seus substancials avantatges, però també analitzant dificultats i línies d'actuació per superar-les. Els mètodes desenvolupats a aquesta Tesi Doctoral són generals i aplicables a uns altres criteris si es disposen dels models adequats. / Reig Bernad, A. (2017). Optimal Control for Automotive Powertrain Applications [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/90624
159

Dosalsal, the floating ones : exploring the socio-cultural impacts of cruise ship tourism on Port Vila, Vanuatu residents, and their coping strategies

Niatu, A. L. January 2007 (has links)
The purpose of this study was to explore the socio-cultural impacts of cruise ship tourism on Port Vila residents and their coping strategies. The study was conducted in Port Vila over the months of June and July 2006. It employs the use of a qualitative research methodology, of participant observation, and semi-structured interviews with a range of tourism stakeholders, including the government, the church and chiefs, as well as a number of small businesses such as public transport operators, small indigenous tour operators and market vendors. These observations and interviews were conducted at the Mama’s Haus project, Centre Point Market Place, and the main wharf area. This thesis was initially aimed at exploring the strategies that the residents of Port Vila used to cope with the impacts caused by cruise ship tourism. As the research progressed, it become apparent from primary data collected that market vendors have not just adapted to the impacts of cruise ship tourism, but that the consequences of their adaptation may be seen as empowering them. They are empowered not just economically, but also psychologically, socially and politically. However, it must be acknowledged that not all small tourist operators in this study felt positively about the impacts of cruise ship tourism; some may be seen as being disempowered. Furthermore, the empowerment of these market vendors is dependent on the continuous flow of cruise ship visits to Port Vila; something beyond their control. The cancellation of future trips or decrease in the number of cruise ship voyages will have significant consequences for the sustainability of this informal sector and the longevity of these micro-enterprises. The study finding implies that coping strategies should not just address how residents and communities cope or respond to tourism, but should also go further by addressing the consequences of the coping strategies adopted.
160

JB-2: America's First Cruise Missile

Quigg, Gary Francis January 2014 (has links)
My research provides a historical and archaeological context for this thesis, in which I argue the JB-2 missile is historically significant as a unique example of the rapid duplication of enemy technology for both physical and psychological retaliation, as a crucial link in the chain of development for America’s cruise missile program, and for its role in early Cold War deterrence. Jet Bomb model number 2 (JB-2), America’s first operationally successful, mass produced cruise missile, developed as a direct copy of the German V-1, with slight variation in manufacture due to differences between German and American components, machinery and tooling. Continuing modifications of the JB-2 during its service life led to improvements in performance, control, and accuracy. From 1944 to 1953, the JB-2 transitioned from a weapon quickly prepared for wartime deployment to an essential test vehicle for the United States Army, Air Force and Navy while supporting the U.S. policy of containment during the early Cold War.

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