Método de Projeções Ortogonais

The problem treated in this dissertation is to establish boundedness for the iterates of an iterative algorithm in projection on a straight line in projections. This problem was analyzed in a paper by Barany et al. in 1994, which found a necessary and suficient condition in the case d = 2, and analyzed further the case d > 2, under some technical conditions. However, this paper uses non-trivial intuitive arguments and its proofs lack suficient rigor. In this dissertation we discuss and strengthen the results of this paper, in order to complete and simplify its proofs

Avaliando o impacto da utilização de renderizações panorâmicas para a navegação em ambientes virtuais

Panoramic rendering is the visualization of three-dimensional objects in a virtual environment through a wide viewing angle. This work investigated if the use of panoramas is able to promote faster searches in a virtual environment. Panoramas allow the presentation of space through less need to change the orientation of the camera, especially for the case of projections spanning 360º surrounding the user, which can benefit searching. However, the larger the angle, more distorted is the visualization of the environment, causing confusion in navigation. The distortion is even bigger when the user changes the pitch of the camera, by looking up or down. In this work we developed a technique to eliminate specifically the distortions caused by changes in pitch, which was called hemispheric projection. Experiments were done to evaluate the performance of search navigation through perspective, cylindrical and hemispherical projections. The results indicate that navigating with perspective projection is superior than navigating with panoramic projections, possibly due to factors such as (i) lack of experience of the participants in understanding the scenes displayed as panoramas, (ii) the inherent presence of distortion in panoramic projections and (iii) a lower display resolution because the objects are presented in smaller sizes in panoramic projections, making the perception of details more difficult. However, the hemispherical projection was better than the cylindrical, indicating that the developed technique provides benefits for navigation compared to current techniques of panoramic projection. The hemispheric projection also provided the least amount of changes of camera orientation, which is an indication that the hemispheric projections may be particularly useful in situations where there are restrictions on the ease to change the orientation. Future research will investigate the performance of cameras interactions on slower devices, such as using only keyboard, or brain-machine interfaces

A dinâmica territorial da cultura e do turismo em Mossoró/RN : uma análise geográfica

The city of Mossoró has been, currently, divulged and known in all Rio Grande do Norte as the cultural capital of the State, in function of the excellent carried through investments, each year, in the cultural sector. The present work is considered to construct an understanding to of the dynamics of the culture and tourism in the city of Mossoró. This work searches also , to verify how this territorial dynamics of the city is processed, by the recent years, in function of the local activities as Mossoró Cidade Junina , Auto da liberdade e Festa de Santa Luzia. An analysis of the occured territorial transformations in Mossoró has been done, decurrent of the activities in study, and the impacts proceeding from the public and private investments, that provoke a new dynamics in the city. Moreover, the perception of the community, the private initiative and the public power in relation to these practical is verified as processes of Mossoró. For this, documentary and bibliographical research has been used. It was accomplished, field research, through the comment not-participant and from the accomplishment of interviews with the municipal public power, main idealizer of the parties and with the private initiative, as sponsor. The local community also participated through the application of questionnaires. It has been concluded that the parties as Mossoró Cidade Junina, Auto da Liberdade and Santa Luzia, have demonstrated a capacity to create and to keep a tourism flow, being Mossoró projection as a tourist destination. The city has through it parties, great part of itself moving in direction to guarantee its accomplishment, what it makes with that its territorial dynamics comes being modified for and for the tourism

Praças públicas caicoense: territorialidades, sociabilidades e identidades

The city, with all its complexity, is marked by the different uses that emerge and give the current composition of its forms, functions, processes and structures (SANTOS, 2008). These uses are responsible for defining the territoriality that engender public squares, especially from the projection of the practices of sociability and pleasure experienced by social groups and urban households, giving rise to the emergence of agreements and conflicts, especially when the public sphere and negotiates a private residence in the same territory. Thus, from analyzes performed in the public squares of the city of Caico / RN in the current context, did a survey of territorialities undertaken by these groups and social aggregates. These squares were seized territories while public use, but marked by the presence of private, becoming as important elements of the urban space caicoense