New strategies for planning and performance evaluation of wireless networks: case studies based on the cross-layer approach

The use of wireless local area networks, called WLANs, as well as the proliferation of the use of multimedia applications have grown rapidly in recent years. Some factors affect the quality of service (QoS) received by the user and interference is one of them. This work presents strategies for planning and performance evaluation through an empirical study of the QoS parameters of a voice over Internet Protocol (VoIP) application in an interference network, as well as the relevance in the design of wireless networks to determine the coverage area of an access point, taking into account several parameters such as power, jitter, packet loss, delay, and PMOS. Another strategy is based on a hybrid approach that considers measuring and Bayesian inference applied to wireless networks, taking into consideration QoS parameters. The models take into account a cross layer vision of networks, correlating aspects of the physical environment, on the signal propagation (power or distance) with aspects of VoIP applications (e.g., jitter and packet loss). Case studies were carried out for two indoor environments and two outdoor environments, one of them displaying main characteristics of the Amazon region (e.g., densely arboreous environments). This last test bed was carried out in a real system because the Government of the State of Pará has a digital inclusion program called NAVEGAPARÁ.

Knowledge and culture: two significant issues for local level development programme analysis

O artigo objetiva propor um arcabouço teórico para analisar programas de desenvolvimento e suas ações em nível local. Em particular, o artigo destaca dois conceitos-chave que devem ser levados em consideração no processo de implementação de programas de desenvolvimento em nível local: conhecimento e cultura. O artigo mostra que o entendimento do conhecimento enquanto construção social contrasta com a perspectiva racional e positivista de que este é derivado exclusivamente da ciência. O artigo mostra que se desenvolvimento é relacionado para a melhoria das condições de vida das pessoas por via de mudanças econômicas e sociais, então, desenvolvimento é mediado e impacta sobre conhecimento e cultura.