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O ateísmo de Richard Dawkins nas fronteiras da ciência evolucionista e do senso comum / Richard Dawkins atheism at the frontiers of evolutionist science and common senseFranco, Clarissa de 09 June 2014 (has links)
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Previous issue date: 2014-06-09 / Fundação de Amparo a Pesquisa do Estado de São Paulo / The object of study is the main Richard Dawkins ideas of atheism and this reception on
the brasilian atheists. Dawkins is one of the leading publishers and militant atheist
movement today, and despite his public facet - released worldwide on websites and in
books of recognized success - there are debates of the author , pertaining to academic
spaces and restricted to scientists, who do not always have congruent to its exhibitions
and public defenders . Internally the walls of science, Richard Dawkins can not find full
verification and corroboration of some central points of his theory that seem to support
its public arguments of atheism, such as the theory and the concept of memetic and
selection gene, ideas presented to the lay public one of his most famous books, The
Selfish Gene (2001a [1976]) and maintained publicly with the status of consolidated
science. We assume that the figures of scientist and militant atheist from Dawkins
mingle in front of the public imagination, which tends to lead his followers to
understand atheism as a more legitimate and true way that religious, being interpreted
that as a way to free choice and the latter undergoes a indoctrination. We believe,
however, that atheism can be understood as subject to natural cognitive mechanisms, as
religion. We take into account the political scene today is favorable to atheists, since we
observed a phenomenon we call "moral atheists revenge", a reversal of official
protection and legitimacy of the state, which has long been welcoming and protecting
the speech religious and today happened to be synchronized with atheistics claims,
being religious in an outdated and uncomfortable place in the democratic debate. These
hypotheses was investigated by means of confrontation between the scientific and
public speeches of Richard Dawkins and through a mixed questionnaire (with open and
closed questions ) that investigated 1022 atheists, noting whether and to what extent
atheism sample follows trends thinking of Richard Dawkins. We observed patterns of
response, three groups: Super Atheists, Moderates Atheists and Discrete Atheists.
Approximately 30% of the sample declare themselves as followers of the author, and
all, nearly 80% have knowledge about any point of the theory of Dawkins / O objeto de estudo consiste nas principais ideias ateístas de Richard Dawkins e na
recepção destas por parte dos ateus inseridos na cultura brasileira. Dawkins é um dos
principais divulgadores e militantes do movimento ateísta da atualidade, e a despeito de
sua faceta pública divulgada em sites mundiais e em livros de reconhecido sucesso
existem debates do autor, concernentes aos espaços acadêmicos e restritos a cientistas,
que nem sempre se apresentam congruentes às suas exposições e defesas públicas.
Internamente aos muros da ciência, Richard Dawkins não encontra plena verificação e
corroboração de alguns pontos centrais de sua teoria que parecem embasar sua
argumentação pública do ateísmo, tais como a teoria da memética e o conceito de
seleção de gene, ideias apresentadas ao público leigo em um de seus mais célebres
livros, O gene egoísta (2001a [1976]) e mantidas publicamente com o status de ciência
consolidada. Consideramos que as figuras de cientista e militante ateu em Dawkins
fundem-se diante do imaginário público, o que tende a levar seus seguidores a
compreenderem o ateísmo como um caminho mais legítimo e verdadeiro que o
religioso, sendo aquele interpretado como um caminho de livre escolha e este último
submetido a uma doutrinação. Acreditamos, no entanto, que o ateísmo pode ser
compreendido como submetido a mecanismos cognitivos naturais, como a religião.
Levamos em conta que o cenário político hoje é favorável aos ateus, uma vez que
observamos um fenômeno que chamamos de vingança moral dos ateus , uma inversão
da proteção oficial e da legitimidade do Estado, que durante muito tempo esteve
acolhendo e protegendo o discurso religioso e hoje passou a se afinizar com
reivindicações ateístas, ficando o religioso em um lugar ultrapassado e incômodo no
debate democrático. Estas hipóteses foram investigadas por meio da confrontação entre
os discursos científico e público de Richard Dawkins e através de um questionário misto
(com questões fechadas e abertas) que investigou 1022 ateus, observando se, e em que
intensidade, o ateísmo da amostra segue as tendências do pensamento de Richard
Dawkins. Pudemos observar nos padrões de resposta, três grupos: Super Ateus, Ateus
Moderados e Ateus Discretos. Aproximadamente 30% da amostra declara-se fã do
autor, e ao todo, perto de 80% tem conhecimento sobre algum ponto da teoria de
Dawkins
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OLSR Fuzzy Cost (OLSR-FC): uma extensão ao protocolo OLSR baseada em lógica Fuzzy e aplicada à prevenção de nós egoístas / OLSR Fuzzy Cost (OLSR-FC): an extension to OLSR protocol based on Fuzzy logic and applied to prevent selfish nodesJosé, Diógenes Antonio Marques 05 June 2014 (has links)
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Previous issue date: 2014-06-05 / This work contributes with an extension to the Optimized Link State Routing protocol
(OLSR) called Fuzzy Cost OLSR (OLSR-FC). In order to prevent selfish nodes as well as
to improve the traffic flow over Mobile Ad-hoc Networks (MANETs), the routing metrics
implemented in OLSR-FC make use of a Fuzzy Inference System (FIS) composed of 8
inference rules. Aiming at the choose of paths with low packet loss, better energy capacity
and high connectivity, OLSR-FC implements a procedure of election of routes that takes
into account the following parameters: Packet Loss Index (PLI), Residual Energy (RE)
and Connectivity Index (CI). The OLSR-FC was evaluated by simulation through the NS-
2, in which two scenarios were implemented: a static one with 10 nodes (in testing phase),
and a mobile one with up to 50 nodes. In the former scenario, a comparison was made
between OLSR-FC and the original OLSR protocol which results showed that OLSR-FC
overcomes OLSR in terms of throughput the packet loss. In the latter scenario, besides the
original OLSR protocol, OLSR-FC was also faced up with the OLSR-ETX, OLSR-ML and
OLSR-MD extensions in terms of the following performance metrics: throughput, energy
consumption, packet loss rate, overhead, delay end-to-end, jitter, and packet delivery rate.
In this context, results pointed that OLSR-FC achieved better performance in scenarios
with a maximum of 10% of selfish nodes in comparison with every OSLR extension
and the OLSR. Besides, by evaluating the main network performance metrics, such as
throughput and delivery packet rate, OLSR-FC achieved eleven favorable cases against
five cases in comparison with OLSR protocol. / O presente trabalho propõe uma extensão ao protocolo Optimized Link State Routing
(OLSR) denominada OLSR Fuzzy Cost (OLSR-FC). A métrica de roteamento utilizada
pelo OLSR-FC faz uso de um Sistema de Inferência Fuzzy (SIF), composto por 8 regras
de inferência, que tem como objetivos evitar nós egoístas e melhorar o fluxo do tráfego nas
redes móveis ad-hoc (MANETs). O critério de escolha de rotas leva em consideração os
seguintes parâmetros: Índice de Perda de Pacotes (IPP), Energia Residual (ER) e Índice
de Conectividade (IC), o propósito disso, consiste em escolher caminhos que possuam
baixa perda de pacotes, melhor capacidade energética e alta conectividade. A proposta
foi avaliada por simulação utilizando o simulador de redes NS-2. Foram considerados na
avaliação dois cenários, um estático com 10 nós (utilizado na fase de testes) e um móvel
com até 50 nós. No cenário estático o OLSR-FC foi comparado ao OLSR e os resultados
mostraram que a proposta obtém vantagens com relação às métricas de desempenho
vazão e perda de pacotes. No cenário móvel o OLSR-FC, além do OLSR, foi comparado
às extensões OLSR-ETX, OLSR-ML e OLSR-MD, com relação as seguintes métricas de
desempenho: vazão, consumo de energia, perda de pacotes, overhead, atraso fim-a-fim,
jitter e taxa de entrega de pacotes. Nesse contexto, os resultados obtidos mostram que em
ambientes com até 10% de nós egoístas o OLSR-FC obtém melhor desempenho que as
extensões testadas e com relação ao OLSR, na mesma situação, avaliando as principais
métricas de desempenho de redes, como vazão e taxa de entrega de pacotes, o OLSR-FC
obteve onze casos favoráveis contra apenas cinco casos do OLSR.
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Prevalência e efeito androcida do endossimbionte Spiroplasma em populações de Drosophila melanogaster / Prevalence and male-killing effect of Spiroplasma endosymbiont in Drosophila melanogaster populationsVentura, Iuri Matteuzzo, 1987- 22 August 2018 (has links)
Orientador: Louis Bernard Klaczko / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T19:31:56Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Genetica Animal e Evolução / Mestre em Genética e Biologia Molecular
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Níveis de seleção: uma avaliação a partir da teoria do \"gene egoísta\" / Levels of Selection: an evaluation from the theory of selfish geneBueno, Maria Rita Spina 10 December 2008 (has links)
Esta dissertação de mestrado aborda a controvérsia em torno de qual é o nível biológico no qual a seleção natural atua, com ênfase na proposta de Richard Dawkins do gene egoísta e nas questões que surgem em torno da mesma. Examina-se um panorama de questões de filosofia da biologia abordadas a partir do problema dos níveis nos quais a seleção natural atua. Esperamos que ao avaliar o impacto da teoria do gene egoísta na problemática evolutiva, consigamos compreender sua importância. O objetivo deste trabalho é filosófico, delineando as questões e clarificando alguns termos do debate, sem se propor a tomar partido por uma ou outra posição. O primeiro capítulo apresenta as origens históricas do debate, partindo do ponto de vista original de Charles Darwin no qual o indivíduo era a entidade efetivamente selecionada. Em seguida, buscamos entender como novas questões empíricas, em especial a busca de explicações biológicas para o altruísmo, conduziram a propostas de seleção de grupo. No segundo capítulo delineamos como o desenvolvimento da genética possibilitou que um novo nível de seleção fosse proposto: o gene, e acompanhamos a exposição de Dawkins sobre o ponto de vista do gene egoísta, em especial a partir de seus dois livros mais relevantes sobre o tema: O gene egoísta e O fenótipo estendido. O terceiro capítulo examina diversas aproximações filosóficas no contexto de resposta à pergunta: o que é uma unidade de seleção?. Nosso estudo é consistente com a tese de que as forças seletivas atuam simultaneamente em diversos níveis. / This Masters thesis studies the controversy over what is the biological level in which natural selection takes place. Emphasis is given to Richard Dawkins proposal of the selfish gene and to the issues that arise therefrom, which include many questions in the philosophy of biology. We hope that by assessing the impact that the theory of the selfish gene has had on the problems of evolution, one may understand its importance. The aim of this study is philosophical, raising questions and clarifying the terms of the debate, without taking side on one or another position. The first chapter presents the historical origins of the debate, starting with the original view of Charles Darwin that the individual is the entity that is effectively selected. We then set out to understand how new empirical problems, specifically the search for biological explanations for altruism, led to proposals of group selection. In the second chapter, we depict how the development of genetics allowed that a new level of selection be proposed: the gene. We analyze Dawkins exposition of the point of view of the selfish gene, especially in the two most important books on the subject: The selfish gene and The extended phenotype. The third chapter examines several philosophical approaches to the question what is a unit of selection?. Our study is consistent with the thesis that selective forces act simultaneously in different levels.
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Role genu \kur{Impl2} v regulaci imunitní odpovědi na bakteriální infekci u \kur{Drosophila melanogaster}ŠOKČEVIČOVÁ, Helena January 2017 (has links)
The main aim of this thesis is to investigate the role of Impl2 gene in the regulation of immune response to bacterial infection in Drosophila melanogaster. The theoretical part provides a conceptual background concerning immunity in drosophila and also it summarizes what is known about the Impl2 gene. In the practical part, the function of Impl2 gene during infection is examined, starting with the location of its production during immune response, the changes of Impl2 gene amount during infection and its essentiality for a proper immune response. Furthermore, it examines the metabolic changes underlying an immune activation in connection to Impl2 gene. Last but not least, it tests how Impl2 gene is connected with the mobilization of energy during Chill Coma Recovery assay.
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Níveis de seleção: uma avaliação a partir da teoria do \"gene egoísta\" / Levels of Selection: an evaluation from the theory of selfish geneMaria Rita Spina Bueno 10 December 2008 (has links)
Esta dissertação de mestrado aborda a controvérsia em torno de qual é o nível biológico no qual a seleção natural atua, com ênfase na proposta de Richard Dawkins do gene egoísta e nas questões que surgem em torno da mesma. Examina-se um panorama de questões de filosofia da biologia abordadas a partir do problema dos níveis nos quais a seleção natural atua. Esperamos que ao avaliar o impacto da teoria do gene egoísta na problemática evolutiva, consigamos compreender sua importância. O objetivo deste trabalho é filosófico, delineando as questões e clarificando alguns termos do debate, sem se propor a tomar partido por uma ou outra posição. O primeiro capítulo apresenta as origens históricas do debate, partindo do ponto de vista original de Charles Darwin no qual o indivíduo era a entidade efetivamente selecionada. Em seguida, buscamos entender como novas questões empíricas, em especial a busca de explicações biológicas para o altruísmo, conduziram a propostas de seleção de grupo. No segundo capítulo delineamos como o desenvolvimento da genética possibilitou que um novo nível de seleção fosse proposto: o gene, e acompanhamos a exposição de Dawkins sobre o ponto de vista do gene egoísta, em especial a partir de seus dois livros mais relevantes sobre o tema: O gene egoísta e O fenótipo estendido. O terceiro capítulo examina diversas aproximações filosóficas no contexto de resposta à pergunta: o que é uma unidade de seleção?. Nosso estudo é consistente com a tese de que as forças seletivas atuam simultaneamente em diversos níveis. / This Masters thesis studies the controversy over what is the biological level in which natural selection takes place. Emphasis is given to Richard Dawkins proposal of the selfish gene and to the issues that arise therefrom, which include many questions in the philosophy of biology. We hope that by assessing the impact that the theory of the selfish gene has had on the problems of evolution, one may understand its importance. The aim of this study is philosophical, raising questions and clarifying the terms of the debate, without taking side on one or another position. The first chapter presents the historical origins of the debate, starting with the original view of Charles Darwin that the individual is the entity that is effectively selected. We then set out to understand how new empirical problems, specifically the search for biological explanations for altruism, led to proposals of group selection. In the second chapter, we depict how the development of genetics allowed that a new level of selection be proposed: the gene. We analyze Dawkins exposition of the point of view of the selfish gene, especially in the two most important books on the subject: The selfish gene and The extended phenotype. The third chapter examines several philosophical approaches to the question what is a unit of selection?. Our study is consistent with the thesis that selective forces act simultaneously in different levels.
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On selfish network creationLenzner, Pascal 30 June 2014 (has links)
Untersuchungsgegenstand dieser Arbeit ist ein spieltheoretisches Modell für die dezentrale Erzeugung von Netzwerken durch eigennützige Agenten. Diese Akteure verfolgen das Ziel, ein zusammenhängendes Netzwerk aufzubauen, welches ihre individuelle Verbindungsqualität maximiert. Direktverbindungen im Netzwerk haben Kosten, weshalb die Agenten ihre Ausgaben für das Erstellen von Direktverbindungen und die damit erzielten Kommunikationskosten ausbalancieren müssen. Dieses Modell wurde vor einem Jahrzehnt von Fabrikant, Luthra, Maneva, Papadimitriou und Shenker eingeführt, um reale Netzwerke, welche aus der Interaktion von eigenützigen Parteien entstanden sind, zu verstehen. Zu solchen Netzwerken zählen das Internet und auch soziale Netzwerke. Die vorliegende Arbeit trägt zu diesem Forschungsvorhaben bei, indem die sogenannten Network Creation Games aus drei Perspektiven betrachtet werden. Die erste Sichtweise ist die Approximationsperspektive. Es wird untersucht, welche Netzwerke von sehr einfachen, in ihrer Berechnungsstärke eingeschränkten Agenten erzeugt werden und wie diese im Vergleich mit Netzwerken von Agenten, die beliebige Berechnungsstärke haben, abschneiden. Als zweite Sichtweise wird die Dynamikperspektive betrachtet. Dazu werden sequentielle Versionen des Modells definiert und anhand dieser wird explizit der Prozess der Netzwerkerzeugung untersucht. Die Hauptfragestellung ist, ob unter der natürlichen Annahme, dass Agenten stets ihre Situation verbessern wollen, der Prozess zu einem Gleichgewicht konvergiert und, falls dem so ist, wie dieser Prozess beschleunigt werden kann. Die Abhandlung wird mit der dritten Sichtweise, der Strukturperspektive, abgerundet. Es werden eine Vielfalt neuer Struktureigenschaften für verschiedene Gleichgewichtskonzepte bewiesen und neue Werkzeuge, die bei der Analyse von Gleichgewichtsnetzwerken mit hohen Direktverbindungskosten hilfreich sind, vorgestellt. / The subject of study in this thesis is a game-theoretic model for decentralized network creation by selfish agents. These agents aim to create a connected network among themselves which maximizes their individual connection quality. Links in the network are costly and therefore agents try to find a trade-off between their cost spent on creating edges and their cost incurred by communicating within the network. This model was proposed a decade ago by Fabrikant, Luthra, Maneva, Papadimitriou and Shenker with the goal of understanding real networks which emerge from the interaction of selfish entities without explicit central coordination, e.g. the Internet or social networks. We contribute to this research endeavor in many ways by considering these so-called Network Creation Games from three perspectives. Our first point of view on these games is the approximation perspective. We analyze which networks are created by very simple computationally bounded selfish agents and how these networks compare to networks built by agents having unlimited computational resources. The second point of view is the dynamics perspective. We turn the model into a sequential version and focus on the process of selfish network creation. For this, we investigate whether natural dynamics like best response dynamics are guaranteed to converge to an equilibrium of the game and if so, how this convergence process may be sped up. We complete the treatment of Network Creation Games with our third point of view: the structure perspective. We provide new structural insights for several equilibrium concepts and introduce new tools which shed light on the structure of equilibrium networks for high edge-cost.
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Réseaux ad hoc véhiculaires : vers une dissémination de données efficace, coopérative et fiable / Vehicular ad hoc networks : towards efficient, collaborativeand reliable data disseminationHaddadou, Nadia 16 June 2014 (has links)
Les réseaux ad hoc véhiculaires (VANETs) permettent le partage de différents types de données entre les véhicules, de manière collaborative. Dans cette thèse, nous nous sommes tout particulièrement intéressés aux applications de sûreté et de sécurité routière, dédiées à l'échange des informations sur l'état de l'environnement routier. Les contraintes de ces applications en termes de qualité de services sont des plus rigoureuses, car l'acheminent de leurs données doit être exhaustif et ne souffrir d'aucun retard pour assurer une information utile et en temps opportun au profit de tous les usagers concernés. Cet acheminement doit faire face aux difficultés induites par la dispersion et la forte mobilité des véhicules, l'absence ou l'insuffisance d'infrastructure, la densité variable du réseau, la surcharge en informations à envoyer et l'étendue des zones géographiques à couvrir. En effet, la problématique de diffusion des données dans les VANETs s'avère non-triviale et de nombreux verrous scientifiques doivent être levés pour permettre un support efficace, collaboratif et fiable pour les applications de sûreté et de sécurité routière.Plus précisément, nous aborderons la problématique de la dissémination collaborative en se posant trois questions : “comment disséminer les données ? À quel moment le faire ? Mais aussi quoi disséminer et comment inciter à le faire ? ” Nous avons apporté des réponses à travers les trois contributions de cette thèse. La première consiste à proposer une stratégie de dissémination efficace, qui soit adaptée à l'importance de l'information échangée et à sa durée de vie, permettant ainsi d'éviter un processus de diffusion intensif. Celui-ci est inapproprié dans ce cas de figure, car il génère de la congestion et beaucoup de redondance. Une étude de performances par simulation est réalisée, laquelle montre une diminution de 90% du taux de messages redondants par rapport au cas de la diffusion par inondation. Afin d'améliorer plus encore les performances du processus de diffusion des messages de sûreté, nous proposons, dans un second temps, un ordonnanceur pour l'accès au canal de communication qui a pour objectif de réduire le nombre de collisions dues aux synchronisations afférentes à l'utilisation du multi-canal dans le standard IEEE 802.11p/1609.4 et donc élever le taux de réception des données. Nous basons notre proposition sur la théorie de l'arrêt optimal, qui décide du moment opportun pour l'envoi d'une information en conciliant occupation du canal, efficacité de l'envoi et délai d'ajournement toléré par une information. Dans notre cas, la théorie de l'arrêt optimal est formulée par un processus de décision Markovien (MDP). Nous montrons ainsi par simulation une amélioration substantielle du taux de réception (de 25%) et une diminution importante des pertes (de 47%).Après s'être intéressé à l'aspect quantitatif des performances du réseau, nous nous intéresserons ensuite à l'amélioration de la fiabilité du processus de diffusion. Cette fiabilité est obtenue grâce à l'incitation des véhicules à la coopération et à l'exclusion des véhicules malicieux de celui-ci. Ceci est réalisé au travers de la proposition d'un modèle de confiance, inspiré des jeux de signaux. Le modèle crée une situation d'équilibre, tel que les différentes parties le composant ne soient pas tentées de le contourner, ainsi découle une auto-sélection des véhicules, laquelle est rapide et peu coûteuse. À notre connaissance, notre modèle est le seul à s'attaquer aux effets néfastes des deux types de véhicules, malicieux et égoïstes, en même temps. Comme précédemment, nous évaluons les performances de notre solution au travers d'une modélisation par une chaîne de Markov et divers jeux de simulation. Ceci a permis de montrer que 100% des véhicules malicieux sont exclus, avec le maintien d'un taux de coopération élevé dans le réseau, soit une amélioration de 42% / Vehicular Ad Hoc Networks (VANETs) allow sharing different kinds of data between vehicles in a collaborative way. In this thesis, we are particularly interested in road safety applications, designed for the exchange of information on road traffic and conditions. This kind of applications have strict Quality of Service (QoS) requirements, as data must be routed thoroughly and without any delays so for assuring the timely delivery of useful information to the drivers. In this context, data routing must face several issues raised by the high mobility and dispersion of vehicles, inadequate or completely lacking infrastructure, a variable network density, network saturation due to the large of information to deliver, and the size of the geographical areas to cover. Indeed, the problem of data dissemination in VANETs is non-trivial, and several research challenges must be solved in order to provide an efficient, collaborative, and reliable support for road safety applications. Specifically, we will address the problem of collaborative data dissemination through the following three questions: “How to perform data dissemination?”, “When should we do it?”, and “What must be disseminated?” We have provided answers to these questions through the three contributions of this thesis. Our first contribution is an efficient dissemination strategy, specifically tailored to the importance of the exchanged information as well as its lifespan, which is able to avoid the intensive dissemination process that generates network congestion and data redundancy. We confirm our statements and validate the performance of our solution by modeling it using a discrete-time Markov chain, which demonstrates the number of necessary retransmissions for all concerned vehicles to receive information. Moreover, we performed extensive simulations that show a reduction of up to 90% of redundant messages with respect to message flooding dissemination strategies. Next, in order to further improve the road safety message dissemination process, we propose a communications channel access scheduler, which aims at reducing the number of collisions caused by IEEE 802.11p/1609.4 multi-channel synchronizations, and thus improving the data reception rate. We base our solution on the optimal stopping theory, which chooses the right moment to send information by balancing the channel occupancy rate, the data delivery efficiency, and the maximum deferment delay tolerated by the information. To this end, we formulate the optimal stopping theory through a Markov decision process (MDP). We show through simulation-based evaluations an improvement of the reception rate of up to 25% and a reduction of up to 47% of message losses. Finally, after being interested in the quantitative aspect of network performance, we centered our efforts on improving the reliability of the dissemination process, which is obtained by motivating vehicles to cooperate and evicting malicious vehicles from the process. To this end, we propose a trust model inspired on signaling games, which are a type of dynamic Bayesian games. Through the use of our model, equilibrium is achieved, thus resulting in a fast and low-cost vehicle self-selection process. We define the parameters of our trust model through a discrete-time Markov chain model. To the best of our knowledge, our solution is the only existing solution that tackles the negative effects introduced by the presence of both malicious and selfish vehicles in a VANET. We evaluated the performance of our solution by modeling it using a Markov chain, and a set of simulations. Our results show that up to 100% of malicious vehicles are evicted while keeping a high cooperation rate, thus achieving an improvement of 42% when compared to other similar solutions
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