5 resultados para large effective population size

em Universidade Federal do Rio Grande do Norte(UFRN)


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One of the agreements assumed at the conference of the United Nations for the Environments and Development which took place in Rio de Janeiro in 1992; through Global Agenda 21, was that the signatory countries would create a national Politics of sustainable development, by means of their national Agenda 21. Demonstrating the relevance of municipal districts and the local communities, during the definitions of new development standards compromised to the transformation of the society, socia1ly and environmentally well-balanced world, it was also agreed on that places under the responsibilities of the municipal districts would promote their own local Agenda 21. We need to point out though that the government has the prerogative and the responsibly of facilitating the population participation process in the construction of national and local Agenda. This made it possible again, to plan the scheming process directly towards the insertion of population participation at the different levels, involving the entire local sectors while establishing a new local partnership through the local municipal government. Thus, we decide to verify the participation of the population in the construction of their local Agenda 21, choosing for the study case Parnamirim municipality from RN. The question which originated the objectives and analysis was formulated on the following terms: Up to which stage was the process of population participation effective in the elaboration of Parnamirims's local Agenda 21? Based on this uneasiness, it was defined as the general objective, the verification of population participation process during the elaboration of Parnamirims's local Agenda 21, aiming at its effectiveness as well as specific objectives; to identify the population representivity, the construction of the local AG 21 in order to identify on which level is the participation based, to verify the strategies used in order to promote the process participation, to identify the motives guiding those involved in the construction of the local Agenda 21. This case study at Parnamirim municipal district demonstrated that there was effective population participation as far as the local Agenda 21 is concerned

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For a long time, we believed in the pattern that tropical and south hemisphere species have high survival. Nowadays results began to contradict this pattern, indicating the need for further studies. Despite the advanced state of the study of bird population parameters, little is known about their variation throughout the year and the factors affecting them. Reproduction, for example, is one factor that may alter adult survival rates, because during this process the breeding pair allocates resources to maintain itself to maintain offspring, making itself more susceptible to diseases and predation. The aim of this study was to estimate survival and population size of a Central and South America passerine, Tachyphonus rufus (Boddaert, 1783), testing hypotheses about the factors that define these parameters. We performed data collection between Nov/2010 and ago/2012 in 12 ha plot, in a fragment of Atlantic Forest in northeastern Brazil. We used capture-mark-recapture methods to generate estimates using Closed Design Robust model in the program MARK. We generated Multi-state models to test some assumptions inherent to Closed Robust Design. The influence of co-variables (time, rain and reproductive cycle) and the effect of transient individuals were measured. Capture, recapture and apparent survival parameters were defined by reproductive cycle, while temporary dispersal was influence by rain. The estimates showed a higher apparent survival during the non-breeding period (92% ± 1%) than during breeding (40% ± 9%), revealing a cost of reproduction and suggesting a trade-off between surviving and reproducing. The low annual survival observed (34%) did not corroborate the pattern of high rates expected for a tropical bird. The largest population size was estimated to be 56 individuals in Nov/11, explained by high recruitment of juveniles, while the lowest observed in May/12: 10 individuals, probably as a result of massive influx of competitor species. Results from this study add to the growing literature on life history of Neotropical species. We encourage studies like this especially in Brazil, where there are few information, and suggest that covariates related to habitat quality and environmental changes should be tested, so that we can generate increasingly reliable models

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The hotel industry is increasingly using the Internet like a management and operational tool. That way, the hotels will be more prepared to offer quality services to their guests and increase their profits as well. However, many managers seem don t perceive the advantages brought from this new digital environment. This thesis analyse the effects of the hotel managers perceptions as for the Internet effectiveness, Internet access, Internet as a communication tool, future importance of the Internet, benefits and drawbacks of the Internet, according to property type (simple, medium comfort and luxe), property size (quantity of the apartaments), age and hotel industry experience of the managers. The methodology utilized was a survey about the hotels that had at least 40 apartments (medium and big property size), were working in Natal-RN and classified in categories in the Guia Quatro Rodas Brasil, totalizing 35 hotels. Through the analysis of variance (ANOVA) and Tukey test, the results showed that the hotel managers with more than 50 apartments, the managers of the hotel more comfortable, the younger managers and the managers less experient in the hotel industry, demonstrated more conscious about the importance of the adoption of the Internet than the rest of the others. The contribution of this work is to offer more knowledge to the hotel executives about how they can use the Internet and show the importance of the web adoption in their properties

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This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.

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This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.