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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.
181

MODELO DE IDS PARA USUÁRIOS DE DISPOSITIVOS MÓVEIS / IDS MODEL FOR USERS OF MOBILE DEVICES

SILVA, Aline Lopes da 26 June 2008 (has links)
Made available in DSpace on 2016-08-17T14:52:48Z (GMT). No. of bitstreams: 1 Aline lopes.pdf: 2261944 bytes, checksum: 0cbbb27a7a17ab362f4fce42298c4b45 (MD5) Previous issue date: 2008-06-26 / Mobile devices are increasing common reality in wireless networks and have integrated the wireless environment, helping to ease and to make available information. Meanwhile, the wireless environment is subject to vulnerabilities because of the way of spreading information that is given through the air, and is subject to interception or even information theft. Mobile Devices in addition of its vulnerability to these vulnerabilities common in wireless environments, are devices with some physical limitations such as lack of processing capacity and memory, beyond the limited battery life. These limitations become critical in this kind of environment, when unidentified threats attack are directed mobile devices. It is necessary to develop an intrusion detection system dedicated to these devices to identify intrusive behaviour, taking into account their physical limitations. This work proposes an intrusion detection system (IDS, Intrusion Detection System) for wireless networks and mobile devices. This is an adaptation and extension of NIDIA-IDS (Intrusion Detection System-Network Intrusion Detection System based on Intelligent Agents). The system acts with two processes: the first one is an information tracking on the device performance and the second one is a wireless network traffic monitoring, analyzing both the traffic of monitored devices. As proof of concepts a prototype was developed and some experiments were carried to validate this solution. / Os dispositivos móveis são uma realidade cada vez mais comum em redes wireless e se integraram ao ambiente wireless, contribuindo para facilidade e disponibilidade da informação. Entretanto, o ambiente wireless está sujeito a vulnerabilidades, devido à forma de propagação da informação que se dá através do ar, estando sujeito a intercepção ou até mesmo roubo das informações. Dispositivos móveis além de estarem sujeitos a essas vulnerabilidades comuns em ambientes wireless, são dispositivos com algumas limitações físicas, como pouca capacidade de processamento e memória, além da vida útil de bateria limitada. Estas limitações tornam-se críticas neste tipo ambiente, quando ameaças não identificadas são direcionadas a dispositivos móveis. Torna-se necessário a implementação de sistema de detecção de intrusão voltado para estes dispositivos a fim de identificar comportamentos intrusivos, levando em consideração suas limitações físicas. Este trabalho propõe um sistema de detecção de intrusão (IDS, Intrusion Detection System) em redes wireless destinados a dispositivos móveis como adaptação e extensão do IDS-NIDIA (Intrusion Detection System- Network Intrusion Detection System based on Intelligent Agents). O mecanismo utiliza dois processos: o primeiro faz o monitoramento de informações sobre o comportamento do dispositivo e o segundo através do monitoramento de tráfego da rede wireless, analisando o tráfego destinado e originado aos dispositivos monitorados. A implementação da arquitetura e os testes realizados demonstram a viabilidade da solução.
182

[en] A FRAMEWORK FOR LOCATION-BASED COMMUNICATION / [pt] UM FRAMEWORK PARA COMUNICAÇÃO BASEADA EM LOCALIZAÇÃO

KLEDER MIRANDA GONCALVES 07 July 2005 (has links)
[pt] A combinação de computação móvel sem fio e tecnologias para a localização de dispositivos possibilitou o surgimento de um novo paradigma de computação conhecido como Serviços Baseados em Localização, cujo objetivo é estudar como prover ao usuário serviços personalizados que dependem da localidade onde este se encontra. Dentre esses serviços, destacam-se aqueles cuja principal função é dar apoio a diferentes formas de comunicação entre usuários de dispositivos móveis. Apesar de vários serviços terem sido desenvolvidos com esse intuito, são poucos os trabalhos que fizeram um levantamento de suas características comuns com o objetivo de projetar uma infra- estrutura genérica que sirva de base para o desenvolvimento de novos serviços. Isso serviu de motivação para esta dissertação, que trata do desenvolvimento de um framework que facilite a construção de serviços para comunicação baseada na localização de usuários móveis. Como estudos de caso, foram instanciados um aplicativo chamado Nita (Notes In The Air), que provê comunicação síncrona e assíncrona entre usuários presentes numa mesma localidade, e um aplicativo para comunicação instantânea similar ao BuddySpace. / [en] The combination of mobile wireless computing and location technology enabled the emergence of a new computing paradigm known as Location-Based Services, whose goal is to study how to provide personalized services to users depending on the their location. Among these services, very useful are the ones which support different kinds of communication between mobile users. Although several services have been developed with this goal, only few work aimed at identifying the common characteristics of these systems, with the goal of designing a generic infrastructure that serves as the basis for the development of new services. This was the main motivation for this thesis work, in which we designed an object framework facilitating the construction of applications for location-based communication among mobile users. As main case studies, we instantiated an application called Nita (Notes In The Air), which provides both synchronous and asynchronous communication between co- located users, and a location-enhanced instant messaging application similar to BuddySpace.
183

Algorithms for efficient and energy-aware network resource management in autonomous communications systems

Mämmelä, O. (Olli) 14 November 2017 (has links)
Abstract According to industry estimates, monthly global mobile data traffic will surpass 30.6 exabytes by 2020 and global mobile data traffic will increase nearly eightfold between 2015 and 2020. Most of the mobile data traffic is generated by smartphones, and the total number of smartphones is expected to continue growing by 2020, which results in rapid traffic growth. In addition, the upcoming 5G networks and Internet of Things based communication are estimated to involve a large amount of network traffic. The increase in mobile data traffic and in the number of connected devices poses a challenge to network operators, service providers, and data center operators. If the transmission capacity of the network and the amount of data traffic are not in line with each other, congestion may occur and ultimately the quality of experience degrades. Mobile networks are also becoming more reliant on data centers that provide efficient computing power. However, the energy consumption of data centers has grown in recent years, which is a problem for data center operators. A traditional strategy to overcome these problems is to scale up the resources or by providing more efficient hardware. Resource over-provisioning increases operating and capital expenditures without a guarantee of increased average revenue per user. In addition, the growing complexity and dynamics of communication systems is a challenge for efficient resource management. Intelligent and resilient methods that can efficiently use existing resources by making autonomous decisions without intervention from human administrators are thus needed. The goal of this research is to implement, develop, model, and test algorithms that can enable efficient and energy-aware network resource management in autonomous communications systems. First, an energy-aware algorithm is introduced for high-performance computing data centers to reduce the energy consumption within a single data center and across a federation of data centers. For network access selection in heterogeneous wireless networks, two algorithms are proposed, a client side algorithm that tries to optimize users' quality of experience and a network side algorithm that focuses on optimizing the global resource usage of the network. Finally, for a video service, an algorithm is presented that can enhance the video content delivery in a controllable and resource-efficient way without major changes in the mobile network infrastructure. / Tiivistelmä Langattoman tietoliikenteen nopean kasvun ennustetaan jatkuvan edelleen lähivuosinakin ja alan teollisuuden arvioiden mukaan matkapuhelinliikenteen määrä ylittäisi globaalisti 30,6 eksatavua vuoteen 2020 mennessä. Tämä tarkoittaisi liikennemäärän kahdeksankertaistumista ajanjaksolla 2015–2020. Älypuhelimet tuottavat suurimman osan matkapuhelinliikenteestä, ja älypuhelimien lukumäärän arvioidaan jatkavan kasvuaan vuoteen 2020 saakka, mikä johtaa nopeaan liikenteen kasvuun. Tämän lisäksi arvioidaan, että 5G verkot ja esineiden Internet tuottavat suuren määrän verkkoliikennettä. Matkapuhelinliikenteen ja laitteiden määrän kasvu tuo haasteita verkko-operaattoreille, palvelun tarjoajille, ja datakeskusoperaattoreille. Mikäli verkossa ei ole tarpeeksi siirtokapasiteettia dataliikenteen määrää varten, verkko ruuhkautuu ja lopulta palvelukokemus kärsii. Matkapuhelinverkot tulevat myös tulevaisuudessa tarvitsemaan datakeskusten laskentakapasiteettia. Datakeskusten energiankulutus on kuitenkin kasvanut viime vuosina, mikä on ongelma datakeskusoperaattoreille. Perinteinen strategia ongelmien ratkaisemiseksi on lisätä resurssien määrää tai tarjota tehokkaampaa laitteistoa. Resurssien liiallinen lisääminen kasvattaa kuitenkin sekä käyttö- että pääomakustannuksia ilman takuuta siitä, että keskimääräinen myyntitulo per käyttäjä kasvaisi. Tämän lisäksi tietoliikennejärjestelmät ovat monimutkaisia ja dynaamisia järjestelmiä, minkä vuoksi tehokas resurssienhallinta on haastavaa. Tämän vuoksi tarvitaan älykkäitä ja kestäviä metodeja, jotka pystyvät käyttämään olemassa olevia resursseja tehokkaasti tekemällä autonomisia päätöksiä ilman ylläpitäjän väliintuloa. Tämän tutkimuksen tavoitteena on toteuttaa, kehittää, mallintaa, ja testata algoritmeja, jotka mahdollistavat tehokkaan ja energiatietoisen verkkoresurssien hallinnan autonomisissa tietoliikennejärjestelmissä. Tutkimus esittää aluksi supertietokonedatakeskuksiin energiatietoisen algoritmin, jonka avulla voidaan vähentää energiankulutusta yhden datakeskuksen sisällä sekä usean eri datakeskuksen välillä. Verkkoyhteyden valintaan heterogeenisissä langattomissa verkoissa esitetään kaksi algoritmia. Ensimmäinen on käyttäjäkohtainen algoritmi, joka pyrkii optimoimaan yksittäisen käyttäjän palvelukokemusta. Toinen on verkon puolen algoritmi, joka keskittyy optimoimaan verkon kokonaisresurssien käyttöä. Lopuksi esitetään videopalvelulle algoritmi, joka parantaa videosisällön jakoa kontrolloidusti ja resurssitehokkaasti ilman että matkapuhelinverkon infrastruktuurille tarvitaan muutoksia.
184

Distributed Wireless Networks : Link Scheduling And Application Delay Modelling

Sunny, Albert 05 1900 (has links) (PDF)
We address several problems that arise in a multihop wireless mesh network. First, we study the problem of joint congestion control, routing and MAC layer scheduling. We formulate the problem as an aggregate utility maximization problem and apply duality theory to decompose the problem into two sub-problems, namely, network layer congestion control and routing problem, and MAC layer scheduling problem. Given the link “prices", the source adjusts its rate based on the cost of the least-cost path to the destination, and sends traffic to the destination along the least-cost path, while link scheduling is carried out based on link prices. Optimal link scheduling for a wireless network is known to be NP-hard. We explore the use of a known centralized greedy heuristic, and develop a distributed algorithm that can schedule independent links based on local information. While the link scheduling algorithm above is for a given set of link prices, the solution to our problem depends on the sequence of price vectors generated by the price update algorithm. This leads us to study convergence issues related to the price update algorithm. Next, we develop a practical protocol which maximizes aggregate utility in a wireless mesh network. We simulate our protocol using Qualnet 4.5 and compare the result with a baseline protocol that uses IEEE 802.11 for link scheduling and AODV for routing. Our proposed protocol requires the durations of slots and subslots to be defined. We develop an approach in which given a single cell wireless mesh network using IEEE 802.11 as a reliable message delivery mechanism, one can find upper and lower bounds on the durations of slots. We employ stochastic ordering to compare distributions of random variables and using some properties of stochastic ordering along with the central limit theorem, we devise a way to compute the above mentioned bounds on the durations. In the second part, we shift our focus to model delays incurred by application packets sent over a WLAN. In this section we model the WLAN as a Random Polling System. The packet arrival process at each node i is assumed to be a stationary and independent increment random process with mean ai and second moment a(2)i . The packet lengths at node i are assumed to be i.i.d random variables Pi with finite mean and second moment. Utilizing available results, we obtain expressions for mean packet delay. Extensive simulations are conducted to verify the analytical results.
185

Modelling and analysis of wireless MAC protocols with applications to vehicular networks

Jafarian, Javad January 2014 (has links)
The popularity of the wireless networks is so great that we will soon reach the point where most of the devices work based on that, but new challenges in wireless channel access will be created with these increasingly widespread wireless communications. Multi-channel CSMA protocols have been designed to enhance the throughput of the next generation wireless networks compared to single-channel protocols. However, their performance analysis still needs careful considerations. In this thesis, a set of techniques are proposed to model and analyse the CSMA protocols in terms of channel sensing and channel access. In that respect, the performance analysis of un-slotted multi-channel CSMA protocols is studied through considering the hidden terminals. In the modelling phase, important parameters such as shadowing and path loss impairments are being considered. Following that, due to the high importance of spectrum sensing in CSMA protocols, the Double-Threshold Energy Detector (DTED) is thoroughly investigated in this thesis. An iterative algorithm is also proposed to determine optimum values of detection parameters in a sensing-throughput problem formulation. Vehicle-to-Roadside (V2R) communication, as a part of Intelligent Transportation System (ITS), over multi-channel wireless networks is also modelled and analysed in this thesis. In this respect, through proposing a novel mathematical model, the connectivity level which an arbitrary vehicle experiences during its packet transmission with a RSU is also investigated.
186

Specifika informačního managementu v síťové topologii / Specifika informačního managemntu v síťové topologii

Buzek, Jiří January 2011 (has links)
This work deals with programs designed to manage data networks and to their use in managerial practice. The purpose is to explain how these programs contribute to a systemic understanding of managed network and system thinking. All these methods are applied on example of two largest wireless ISP companies in South Bohemia. The dissertation explains the issue of making mental models of the managed network, which concerns specially managers of ISP companies. The work is not an administrator view at programs for network management, but rather a management view and instructions how to use these programs in management decisions to solve complex problems and future development of managed network.
187

Modeling Security and Cooperation in Wireless Networks Using Game Theory

Kamhoua, Charles A. K. 27 May 2011 (has links)
This research involves the design, development, and theoretical demonstration of models resulting in integrated misbehavior resolution protocols for ad hoc networked devices. Game theory was used to analyze strategic interaction among independent devices with conflicting interests. Packet forwarding at the routing layer of autonomous ad hoc networks was investigated. Unlike existing reputation based or payment schemes, this model is based on repeated interactions. To enforce cooperation, a community enforcement mechanism was used, whereby selfish nodes that drop packets were punished not only by the victim, but also by all nodes in the network. Then, a stochastic packet forwarding game strategy was introduced. Our solution relaxed the uniform traffic demand that was pervasive in other works. To address the concerns of imperfect private monitoring in resource aware ad hoc networks, a belief-free equilibrium scheme was developed that reduces the impact of noise in cooperation. This scheme also eliminated the need to infer the private history of other nodes. Moreover, it simplified the computation of an optimal strategy. The belief-free approach reduced the node overhead and was easily tractable. Hence it made the system operation feasible. Motivated by the versatile nature of evolutionary game theory, the assumption of a rational node is relaxed, leading to the development of a framework for mitigating routing selfishness and misbehavior in Multi hop networks. This is accomplished by setting nodes to play a fixed strategy rather than independently choosing a rational strategy. A range of simulations was carried out that showed improved cooperation between selfish nodes when compared to older results. Cooperation among ad hoc nodes can also protect a network from malicious attacks. In the absence of a central trusted entity, many security mechanisms and privacy protections require cooperation among ad hoc nodes to protect a network from malicious attacks. Therefore, using game theory and evolutionary game theory, a mathematical framework has been developed that explores trust mechanisms to achieve security in the network. This framework is one of the first steps towards the synthesis of an integrated solution that demonstrates that security solely depends on the initial trust level that nodes have for each other.
188

A novel framework to promote eco-driving through smartphone-vehicle integration

Meseguer Anastasio, Javier Enrique 01 December 2017 (has links)
It was not that long ago, just in the first half on the 1990s, when mobile phones were first introduced, being big and expensive. All you could do with them was to make phone calls. Since then mobile devices have experienced a great technological advance: we carry smartphones in our pockets that provide Internet access, having accelerometers that can measure acceleration, a gyroscope that can provide orientation information, different wireless interfaces such as Bluetooth connections, and above all, great computing power. On the other hand, the automobile industry has evolved significantly during the last 10 years. One of the most exciting advances in vehicle development is vehicle-to-vehicle V2V communication, which allows cars to communicate with each other over a dedicated Wi-Fi band, and share information about vehicle speed, route direction, traffic flow, and road and weather conditions. An example of such a system is GM's (General Motors) OnStar, introduced in 1996, and that provides automatic response in case of an accident, stolen-vehicle recovery, remote door unlock, and vehicle diagnostics. Also, the standard On Board Diagnosis (OBD-II), available for several years, allows us to connect to the Electronic Control Unit (ECU) via a Bluetooth OBD-II connector. This connection interface allows connectivity between the smartphone and the vehicle, and can be purchased for just over 15 euros. The spectrum of possibilities that arise when combining the car and the smartphone is unlimited, such as performing the diagnosis of the car by assuming the tasks performed by the car's On Board Unit (OBU), or sending the collected data to a platform where the diagnosis or maintenance of the system can be realized in order to detect possible faults, help you to save gas and reduce environment pollution, and notify you of your car's problems, among other features. The general objective pursued with this doctoral thesis is to help drivers to correct bad habits in their driving. To achieve this we promote the combination between smartphones and vehicular networks to design and develop a platform able to offer useful tips to achieve safer driving and greater fuel economy. It is well-known that intelligent driving can lead to lower fuel consumption, with the consequent positive impact on the environment. The proposal that has been carried out in this doctoral thesis begins with the data capture from the vehicles' OBD-II port and data analysis through the use of graphs, maps, and statistics, both, on the server itself and in the smartphone's application developed. We applied data mining techniques and neural networks to analyze, study and generate a classiffication on driving styles based on the analysis of the characteristics of each specific route used for testing. In a second phase, we demostrate the relationship between fuel consumption and driving style. To achieve that goal, the first thing that we had to realize was how to apply different algorithms for the instantaneous consumption calculation (this parameter cannot be obtained directly from the vehicle ECU). Later, we studied and analyzed all data that was collected from the drivers who shared their monitored data with the server. Although drivers do not recognize themselves as being in a state of anxiety while driving, they are more stressed than in any other daily activity, for example, when trying to stay in the right lane, keeping the car at a certain speed, and starting and stopping the vehicle. In general, drivers are more concentrated than they think, which causes an increase in the heart rate. Many factors influence heart rate while at rest, e.g. stress, medications, medical conditions, even genes play a role. In our study we also investigate how stress and the driving behavior influence the heart rate. So, in the last phase, we demostrate the correlation between heart rate and driving style, showing how the driving style can make the heart rate vary by 3 %. / No hace mucho tiempo, tan sólo en la primera mitad en la década de los 90, cuando los teléfonos móviles aparecieron, eran grandes y caros, todo lo que se podía hacer con ellos era realizar llamadas telefónicas. Desde entonces los dispositivos móviles han experimentado un gran avance tecnológico, llevamos teléfonos inteligentes en el bolsillo con acceso a Internet, acelerómetros que calculan la aceleración instantánea, giroscopios que proporcionan información de orientación, diferentes conexiones inalámbricas como Bluetooth, y sobre todo, gran capacidad de computación. Por otro lado, la industria del automóvil ha evolucionado mucho durante los últimos 10 años. Uno de los avances más interesantes en el desarrollo de vehículos ha sido la conectividad, V2V, o comunicación vehículo a vehículo, permite a los automóviles comunicarse mediante Wi-Fi y compartir información sobre la velocidad del vehículo, la dirección de la ruta actual, el tráfico, así como las condiciones de la carretera y las condiciones ambientales. Por otra parte, el estándar On Board Diagnosis (OBD-II), disponible desde hace varios años, permite conectarnos de forma sencilla a la ECU (Electronic Control Unit) mediante un conector Bluetooth OBD-II. Este interfaz de conexión permite la conectividad entre el dispositivo móvil y el vehículo, se puede adquirir por poco más de 15 euros. El espectro de posibilidades que surgen al combinar el automóvil y el Smartphone es amplísimo, como por ejemplo realizar el diagnóstico del coche a través del móvil asumiendo las tareas que hace la unidad On Board Unit (OBU) del coche, o bien enviar los datos recogidos a una plataforma donde se pueda realizar el diagnóstico o mantenimiento del sistema, detectando posibles fallos puede ayudar a ahorrar en el consumo de combustible, notificar los problemas del coche en tiempo real, entre otras características. El objetivo general que se persigue con esta tesis doctoral es ayudar al conductor a corregir malos hábitos en su forma de conducción. Conseguimos esto mediante la combinación entre smartphones y las redes vehiculares, diseñamos y desarrollamos una plataforma capaz de ofrecer consejos útiles para conseguir una conducción más segura y un mayor ahorro de combustible. Es conocido que una conducción inteligente puede llevarnos a un menor consumo de combustible, con el consiguiente impacto positivo que ello conlleva sobre el medio ambiente. La propuesta que se ha llevado a cabo en esta tesis doctoral comienza con la obtención de los datos desde el OBD-II del coche y su presentación y análisis mediante el uso de gráficas, mapas, estadísticas, tanto en el propio servidor como en la aplicación móvil desarrollada para la obtención de datos recibidos desde la ECU. Se aplicaron técnicas de minería de datos y redes neuronales para analizar, estudiar y generar una clasificación sobre los estilos de conducción en base al análisis de las características de la vía sobre la que ha realizado la ruta. En una segunda fase se demostró la relación entre el consumo de combustible con el estilo de conducción, para ello lo primero que tuvimos que realizar fue aplicar diversos algoritmos para el cálculo del consumo instantáneo, este parámetro no es posible obtenerlo directamente de la ECU del vehículo. Posteriormente se realizó el estudio y el análisis de todos los datos que se recogieron de los conductores que se prestaron a la realización del estudio enviando los datos al servidor. Muchos factores influyen en la frecuencia cardíaca en reposo, por ejemplo, el estrés, los medicamentos, las condiciones médicas, incluso los genes tienen su influencia, el envejecimiento tiende a acelerarlo, y el ejercicio regular tiende a ralentizarlo. En nuestro estudio también investigamos cómo el estrés y el comportamiento en la conducción influyen en la frecuencia cardíaca. En la última fase vemos la correlación existente entre el ri / No fa molt de temps, tan sols en la primera mitat en la dècada dels 90, quan els telèfons mòbils van aparéixer, eren grans i cars, tot el que es podia fer amb ells era realitzar telefonades. Des de llavors els dispositius mòbils han experimentat un gran avanç tecnològic, portem telèfons intel_ligents en la butxaca amb accés a Internet, acceleròmetres que calculen l'acceleració instantània, giroscopis que proporcionen informació d'orientació, diferents connexions sense _ls com Bluetooth, i sobretot gran capacitat de computació. D'altra banda, la indústria de l'automòbil ha evolucionat molt durant els últims 10 anys. Un dels avanços més interessants en el desenrotllament de vehicles ha sigut la connectivitat, V2V, o comunicació vehicle a vehicle, permet als automòbils comunicar-se per mitjà de la banda de Wi-Fi i compartir información sobre la velocitat del vehicle, la direcció de la ruta actual, les condicions del trà_c, així com l'estat de la carretera i les condicions ambientals. D'altra banda l'estàndard On Board Diagnosi (OBD-II), disponible des de fa diversos anys, permet connectar-nos de forma senzilla a l'ECU (Electronic Control Unit) per mitjà d'un connector Bluetooth OBD-II. Esta interfície de connexió permet la connectivitat entre el dispositiu mòbil i el vehicle, es pot adquirir per poc més de 15 euros. L'espectre de possibilitats que sorgixen al combinar l'automòbil i el Smartphone és il_limitat, com per exemple realitzar el diagnòstic del cotxe a través del móvil assumint les tasques que fa la unitat On Board Unit (OBU) del cotxe, o bé enviar les dades arreplegades a una plataforma on es puga realitzar el diagnòstic o manteniment del sistema, detectant possibles fallades, ajuda a estalviar en el consum de combustible, noti_car els problemes del cotxe en temps real, entre altres característiques. L'objectiu general que es perseguix amb esta tesi doctoral és ajudar al conductor a corregir mals hàbits en la seua forma de conducció. Aconseguim açò mitjançant de la combinació entre smartphones i les xarxes vehiculares, dissenyem i desenrotllem una plataforma capaç d'oferir consells útils per a aconseguir una conducció més segura i un major estalvi de combustible. És conegut que una conducció intel_ligent pot emportar-nos a un menor consum de combustible, amb el consegüent impacte positiu que això comporta sobre el medi ambient. La proposta que s'ha dut a terme en esta tesi doctoral comença amb l'obtenció de les dades des de l'OBD-II del cotxe i la seua presentació i anàlisi per mitjà de l'ús de grà_ques, mapes, estadístiques, tant en el propi servidor, com en l'aplicació mòbil desenrotllada per a l'obtenció de dades rebudes des de l'ECU. S'apliquen tècniques de mineria de dades i xarxes neuronals per a analitzar, estudiar i generar una classi_cació sobre els estils de conducció basant-se en l'anàlisi de les característiques de la via sobre la qual ha realitzat la ruta. En una segona fase es va a demostrar la relació entre el consum de combustible amb l'estil de conducció, per a això la primera cosa que vam haver de realizar va ser aplicar diversos algorismes per al càlcul del consum instantani, este paràmetre no és possible obtindre-ho directament de l'ECU del vehicle. Posteriorment es va realitzar l'estudi i l'anàlisi de totes les dades que es van arreplegar dels conductors que es van prestar a la realització de l'estudi enviant les dades al servidor. Molts factors in_ueixen en la freqüència cardíaca en repòs, per exemple, l'estrès, els medicaments, les condicions mèdiques, _ns i tot els gens tenen la seua in_uència, l'envelliment tendeix a accelerar-ho, i l'exercici regular tendeix a ralentir-ho. En el nostre estudi només estem interessats en com l'estrès i el comportament en la conducció in_ueixen en la freqüència cardíaca. En l'última fase vam veure la correlació existent entre el ritme cardíac i l'estil de conducci / Meseguer Anastasio, JE. (2017). A novel framework to promote eco-driving through smartphone-vehicle integration [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/84287 / TESIS
189

Optimalizace procesu handoveru v reálném síťovém prostředí / Optimization of hand-over process in real network environment

Hornyak, Tomáš January 2011 (has links)
This Master´s thesis deals especially with exploration of the handover process and with searching for ways of in?uencing this process. The goal of this thesis is to create tools for recording of access point utilization and in?uence the handover of wireless clients based on the obtained data. An access point with open ?rmware, which allows low-level management, was necessary for practical tests. First chapter deals with a survey of current o?er of open ?rmware available for access points and then the appropriate candidate for this thesis is chosen – the OpenWRT project. Second chapter deals with the con?guration of OpenWRT system and basic settings of the chosen wireless router – TP-Link TL-WR1043ND. Next chapter deals with analysis of the handover process in wireless networks. Information obtained by this analysis is used during the creation of the graphic application. The fourth chapter presents the basics of Microsoft Native Wi-Fi API and introduces basic functions used by this API. Those functions were used during the creations of the application. Last two chapters present the created graphic application. The ?fth chapter deals with the application design and examination of its functionality and used functions. Last chapter then documents usability of the application in real environment.
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Bezdrátová senzorická síť pro sušárnu chmele / Wireless sensoric network for hop drying facility

Čapek, Lukáš January 2011 (has links)
The purpose of this project is to build a wireless sensor network for measuring temperature and relative humidity in hop drying facility. This is a monitoring device, consists of several sensor units and one control and display unit. Display unit coordinates a whole network and can display data on LCD or download collected data to PC. Sensor unit measures a relative humidity, temperature, battery voltage and transmits data to display unit. Units contain a transceiver which operates in ISM band 868 MHz. Circuits are driven by 8-bits microcontroller Freescale.

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