A social network approach to trust management in VANETs

In the past few years, vehicular ad hoc networks(VANETs) was studied extensively by researchers. VANETs is a type of P2P network, though it has some distinct characters (fast moving, short lived connection etc.). In this paper, we present several limitations of current trust management schemes in VANETs and propose ways to counter them. We first review several trust management techniques in VANETs and argue that the ephemeral nature of VANETs render them useless in practical situations. We identify that the problem of information cascading and oversampling, which commonly arise in social networks, also adversely affects trust management schemes in VANETs. To the best of our knowledge, we are the first to introduce information cascading and oversampling to VANETs. We show that simple voting for decision making leads to oversampling and gives incorrect results in VANETs. To overcome this problem, we propose a novel voting scheme. In our scheme, each vehicle has different voting weight according to its distance from the event. The vehicle which is more closer to the event possesses higher weight. Simulations show that our proposed algorithm performs better than simple voting, increasing the correctness of voting. © 2012 Springer Science + Business Media, LLC.

Limitations of trust management schemes in VANET and countermeasures

Vehicular networks ensure that the information received from any vehicle is promptly and correctly propagated to nearby vehicles, to prevent accidents. A crucial point is how to trust the information transmitted, when the neighboring vehicles are rapidly changing and moving in and out of range. Current trust management schemes for vehicular networks establish trust by voting on the decision received by several nodes, which might not be required for practical scenarios. It might just be enough to check the validity of incoming information. Due to the ephemeral nature of vehicular networks, reputation schemes for mobile ad hoc networks (MANETs) cannot be applied to vehicular ad hoc networks (VANET). We point out several limitations of trust management schemes for VANET. In particular, we identify the problem of information cascading and oversampling, which commonly arise in social networks. Oversampling is a situation in which a node observing two or more nodes, takes into consideration both their opinions equally without knowing that they might have influenced each other in decision making. We show that simple voting for decision making, leads to oversampling and gives incorrect results. We propose an algorithm to overcome this problem in VANET. This is the first paper which discusses the concept of cascading effect and oversampling effects to ad hoc networks. © 2011 IEEE.

Social and environmental indexes to determine the impacts of closed neighbourhoods in Brazil

São Paulo State, in Brazil, is getting increasingly crowded, like in other third world countries around the world, so should give great importance to city development. This work considered the phenomenon of closed neighbourhoods (CN) as an important factor to city planning, papers report many impacts of this model of neighbourhoods in other countries, but in Brazil its impacts are not yet well listed in the literature. The aim of this work was to determine indicators to achieve the social and environmental performances and verify their applicability on three different closed neighbourhoods in São Paulo state, Brazil. The indicators were condensed on indexes: water management, waste management, energy and emissions, legal compliance, environment and buildings, risk management, health and education and governance. The preliminary results indicated several social and environmental problems in all indexes. © 2013 WIT Press.

Os quilombos do Vale do Ribeira e o movimento social: o movimento dos ameaçados por barragens do Vale do Ribeira (MOAB)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Arquitetura moderna paulista, imaginário social urbano, uso e apropriação do espaço

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Espacialidade e ativismo social na zona leste de São Paulo: o caso do Coletivo Dolores Boca Aberta Mecatrônica de Artes

Pós-graduação em Geografia - IGCE

Estudo comparativo dos programas de habitação social nas cidades de Franca/Brasil e Praia/Cabo Verde: convergências e discrepâncias

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A violência entre adolescentes no conjunto habitacional Orlando Quagliato no município de Ourinhos: realidade ou mito ?

Pós-graduação em Ciências Sociais - FFC

Campo Grande e a rua 14 de Julho: tempo, espaço e sociedade. -

Pós-graduação em Geografia - FCT

A inter-relação entre competência em informação e a construção de conhecimento corporativo em ambiência de redes organizacionais: um estudo no SEBRAE-SP - Escritório Regional de Bauru

Pós-graduação em Ciência da Informação - FFC

As matrizes do samba carioca e carnaval: algumas reflexões sobre patrimônio imaterial

Nosso trabalho busca discutir o samba carioca e o documento produzido pelo Centro Cultural Cartola para registrar as matrizes do samba do Rio de Janeiro como um bem imaterial no Livro das Formas de Expressão criado pelo IPHAN em 2000. Para isso, buscamos compreender as diferentes expressões deste gênero musical e suas transformações narrativas, melódicas e timbrísticas que o transformaram de música marginal a símbolo de brasilidade e que o tornaram o ritmo da maior festa brasileira: o carnaval. Compreendemos que tal processo se deu em consonância com as transformações políticas, sociais e urbanísticas que a cidade do Rio de Janeiro sofreu nas primeiras décadas do século XX e que, o inventário e registro das matrizes do samba carioca é fruto não apenas dos anseios da comunidade de sambistas, mas também do diálogo destes com intelectuais e gestores públicos. Além disso, tal política voltada para a preservação e salvaguarda dos bens imateriais se coaduna com políticas e projetos urbanísticos de transformação de certos espaços citadinos em verdadeiros museus a céu aberto, como é o caso do Museu a Céu Aberto do Morro da Providência e da construção da Cidade do Samba, que expressam uma preocupação com a revitalização da área, a valorização imobiliária e o incremento da indústria do turismo.

Acessibilidade aos serviços de saúde pública no município de Rio Claro - SP

O acesso da população aos serviços de saúde é de fundamental importância para uma eficiente assistência à saúde. A localização geográfica dos serviços é um dos fatores que interferem nessa acessibilidade, como também as formas de locomoção que possibilitem o acesso e o estado das vias e calçadas que cercam o estabelecimento de saúde. Pretendeu-se estudar o acesso aos serviços de saúde no município de Rio Claro, estado de São Paulo. Assim, a contribuição da abordagem geográfica abre a possibilidade do estabelecimento de novas linhas de estudo, planejamento e gestão, que surgem através da relação entre Geografia Humana e Saúde Pública

Dinâmica territorial do conhecimento e da inovação: uma análise da Incubadora Tecnológica de São Carlos (SP)

Pós-graduação em Geografia - IGCE

Multi-Agent Simulation of Urban Social Dynamics for Spatial Load Forecasting

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Social support and infant malnutrition: a case-control study in an urban area of Southeastern Brazil

The relationship between malnutrition and social support was first suggested in the mid-1990s. Despite its plausibility, no empirical studies aimed at obtaining evidence of this association could be located. The goal of the present study was to investigate such evidence. A case-control study was carried out including 101 malnourished children (weight-for-age National Center for Health Statistics/WHO 5th percentile) aged 12-23 months, who were compared with 200 well-nourished children with regard to exposure to a series of factors related to their social support system. Univariate and multiple logistic regressions were carried out, odds ratios being adjusted for per capita family income, mother's schooling, and number of children. The presence of an interaction between income and social support variables was also tested. Absence of a partner living with the mother increased risk of malnutrition (odds ratio 2.4 (95 % CI 1.19, 4.89)), even after adjustment for per capita family income, mother's schooling, and number of children. The lack of economic support during adverse situations accounted for a very high risk of malnutrition (odds ratio 10.1 (95 % CI 3.48, 29.13)) among low-income children, but had no effect on children of higher-income families. Results indicate that receiving economic support is an efficient risk modulator for malnutrition among low-income children. In addition, it was shown that the absence of a partner living with the mother is an important risk factor for malnutrition, with an effect independent from per capita family income, mother's schooling, and number of children.