Implementação e avaliação de desempenho do protocolo CSMA/CA IEEE 802.15.4 sobre a plataforma SimpliciTI e microcontroladores MSP430

Trabalho de conclusão de curso (graduação)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Elétrica, 2015.Este trabalho apresenta a implementação do protocolo CSMA/CA IEEE 802.15.4, de tempo não compartimentado, sobre a plataforma SimpliciTI, da Texas Instruments. O desempenho do protocolo implementado é avaliado sobre uma rede de sensores baseada nos microcontroladores MSP430, e comparado com o desempenho do protocolo CSMA/CA original implementado na plataforma SimpliciTI. Os desempenhos de ambos os protocolos são avaliados sobre redes com diferentes números de nós e taxas de geração de pacotes, e comparados segundo o número de recuos ( backo s ) necessários para entrega de pacotes com sucessos, número de pacotes perdidos e vazão efetiva da rede.This work presents an implementation of the non-slotted CSMA/CA MAC protocol of the IEEE 802.15.4 standard over the SimpliciTI plataform, by Texas Instruments. The performance of the implemented protocol is evaluated over a sensor network based on MSP430 microcontrollers, and compared against the peformance of SimpliciTI's original CSMA/CA protocol. Both protocols are evaluated under di erent number of nodes and data rates, according to the number of backo stages needed to successfully deliver data packets, the number of data packets delivered unsuccessfully, and network throughput

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data