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Rede overlay de suporte a ambientes virtuais colaborativos em redes veiculares
(Universidade Federal de São Carlos, 2009-07-13) Meneguette, Rodolfo Ipolito; Araujo, Regina Borges de; https://lattes.cnpq.br/8964123297688432; https://lattes.cnpq.br/4981889689994770
Collaborative Virtual Environments (CVEs) are synthetic 3D environments shared by multiple remotely located users with a common goal: the access to the environment through avatars (graphical representations of the user). CVEs are becoming popular on mobile devices such as handheld devices and cell phones, through games and simulations for users entertainment and comfort. These virtual environments require low latency and high scalability so that a large number of participants can interact in a consistent way without losing the immersion feeling. Therefore it entails a major concern on participants s connection strategies, especially when these environments are implemented on moving vehicles, because the unique characteristics of a vehicular ad hoc network (VANETs) like high mobility of nodes, high speed transmission and a highly dynamic topology demand a complex structure to overcome these limitations. These characteristics lead us to communication challenges among participants and to the dissemination of actions results of their avatars in the CVE and / or the state change of an object for all participants. The communication support network should be able to cope with the entrance of an increasing number of participants in the CVE without affecting these users feeling of presence. In order to overcoming the challenges of scalability and ensuring a uniform view of the virtual world for all users in VANETs networks, this paper presents a design and evaluation of an overlay network, specifically a peer-to-peer (p2p) network, which aims at providing connectivity between users of a CVE, in addition to updating the status of avatars and objects in the CVE for all participants, ensuring that information is delivered in the shortest time possible.
Mapeamento de QTL nos cromossomos 24 e 29 para medidas de peso, resistência a carrapato e estresse térmico em uma população F2 (Gir X Holandês)
(Universidade Federal de São Carlos, 2009-07-13) Cervini, Marcelo; Regitano, Luciana Correia de Almeida; https://lattes.cnpq.br/6385352144935008
In the latest years, Brazil became one of the most important countries regarding the production and exportation of animal-based food. Improvements on the sanitary conditions and animal research applied to animal production were some of the elements which have placed Brazil in this highlight position. However, difficulties on controlling the tick Rhipicephalus (Boophilus) microplus and herd management limitations concerning heat stress situations hamper a greater development on the national production. A significant part of the variation on these traits is controlled by many genes (Quantitative Trait Loci - QTL). The identification of loci influencing these traits is important for genetic improvement programs. The objective of this study was to identify and map QTL for tick resistance and heat stress tolerance in the chromosomes 24 and 29, as well as QTL related to growth traits in a F2 population (Gir x Holstein) by using the microsatellites scan methodology. No QTL was identified for the tick number found. However, on chromosome 24, an indicative QTL (P<0.10) for birth weight was identified. On chromosome 29, significant QTL for sweating rate (P<0.01) and respiration frequency (P<0.05) were also recognized. In addition, a suggestive QTL (P<0.05) for standardized weaning weight was found in chromosome 29 in one of the families. These results could help to improve the knowledge about the general factors affecting the evaluated traits, making possible the development of more efficient selection strategies for the environment conditions in the Brazilian production systems.