19 resultados para projective relativity

em Universidade Federal do Rio Grande do Norte(UFRN)


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Sustainability in buildings, while reducing the impact on the environment, contributes to the promotion of social welfare, to increase the health and productivity of occupants. The search for a way of build that meets the aspirations and development of humanity without, however, represent degradation of the environment, has become the great challenge of contemporary architecture. It is considered that the incorporation of principles that provide a sustainable building with careful choices of design solutions contribute to a better economic and thermal performance of the building, as well as functional and psychological comfort to its users. Based on this general understanding, this paper presents an architecture project aimed to health care whose the solutions adopted follow carefully the relevant legislation and sets his sights on the theme of sustainability. The methodology began with studies on the themes of verification service of deaths, sustainability and those application in construction developed through research in academic studies and analysis of architectural projects, using them like reference for the solutions adopted. Within the project analysis was performed a visit to the verification service of deaths in the city of Palmas in Tocantins, subsidizing information that, plus the relevant legislation, led to functional programming and pre-dimensional of the building to be designed. The result of this programming environments were individual records with information from environmental restrictions, space required for the development of activities, desirable flow and sustainability strategies, that can be considered as the first product of relevance of the professional master's degree. Finally we have outlined the basic design architecture of a Verification Service of Death SVO/RN (in portuguese), whose process of projecting defined as a guiding line of work four points: the use of bioclimatic architecture as the main feature projectual, the use of resources would provide minimal harm to the environment, the use of modulation and structure to the building as a form of rationalization and finally the search for solutions that ensure environmental and psychological comfort to users. Importantly to highlight that, besides owning a rare theme in literature that refers to architectural projects, the whole project was drawn up with foundations in projective criteria that contribute to environmental sustainability, with emphasis on thermal performance, energy efficiency and reuse of rainwater

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The general aim of the research was to comprehend the Social Representations constructed by the man in the face of his companion s risk pregnancy caused by hypertensive syndromes. The study is of exploratory and descriptive character in a qualitative approach developed at two public maternity hospitals, both located in Natal-RN, with 65 men whose wives had undergone high-risk pregnancy. The project was submitted to the Ethics on Research Committee of the Federal University of Rio Grande do Norte, Brazil (CEP-UFRN), with favorable report no. 81/07. For data collection, the following multimethods were employed: a word free association test; a projective test for registering mental images; and a semistructured interview schedule. The speech contents were analyzed in accordance with the Theory of Social Representations and complemented by the Central Nucleus Theory. The discussion of the results was grounded on literary findings of the companion s participation in pregnancy as well as in risk pregnancy associated with hypertensive syndromes. The data showed fear as representation s central nucleus, while recollections of that feeling referred to death of both companion and child in addition to fear of the unknown. The categories preoccupation and carefulness, other feelings, and clinical picture of the disease represented components of the peripheral nucleus. The results concerning mental images followed the same category criteria of the word free association test fear, other feelings, preoccupation, carefulness, and clinical picture of the disease. After being processed in accordance with the principles of content analysis, the statements originated three thematic unities: fear and insecurity in the presence of the companion s risk pregnancy; attitudes of carefulness to the risk pregnancy of the partner; and humanized assistance during the companion s risk pregnancy. Considering the results, the conclusion is that the partner s risk pregnancy caused by hypertensive syndromes represents, for the man, feelings of fear, preoccupation, insecurity, lack of acceptance and information, as well as attitudes of carefulness. The results reveal necessity of reorganizing the obstetric assistance with an eye to including the man as participant in the reproductive process. That demands extension of humanized carefulness to the companion with a view to make him an active coadjutor in the assistance of high-risk pregnant

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This work focalize the institutional and educational evaluation, aiming to investigate the Municipal System Institutional Evaluation Performance of Teresina City Piauí (2001-2005), and to reflect about Institutional System Performance and its contribution to compose a new learning evaluation practice. In this sense, classifies elements about the evaluation practice in two Elementary Education municipal public schools, involving Education Municipal Bureau technicians as managers, pedagogues, teachers and students. Based on the ethnographic studies principles in the educational area, the work employs investigative procedures like document analysis, interviews with groups and individuals and also participator s comments. Intending to comprehend the complexity produced by the institutional and education evaluation processes, the wok reveals the Institutional Evaluation legal and educational political basis and the several positions assumed by the Learning Evaluation, as a classification tool or as a learning enhancement. This work points, as results, to a evaluation culture bipolarity carried out by the Municipal Education System as a explicit control and regulation toll, related to the classification and learning in a interaction process that operates both in the pressure and the reflection, as a culture practice established between excellence of logic and learning. The evaluation history has been construct on the evaluation actions dialectics, joint simultaneously between the Institutional Evaluation Performance and the learning evaluation. The senses, meanings and actions bipolarity is a interaction process product sustained between the institutional evaluation, under the scholar ranking application, and the learning evaluation. In this relativity, the teacher evaluation practice is found, ruled by interesting, thoughts and actions on the school evaluation, allowing a higher security and support to the learning results. Grounded in the researched reality, its possible to say that the teacher s evaluation practice is diversified, with different characteristics, when it is done in the learning search and in the learning intention. In the first case, reflects, rearranges and constructs new actions that lead the student to produce learning. In the second, shows the will, the wish of learning, but is a weak action, producing a not really significant learning and development; as a result, remains the mark approach as a determinant in the student future. The work s hope is to contribute not just to rethink these two evaluations dimensions the institutional and the learning ones but also to organize the school and to improve the pedagogic process

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The issue of multi-classes in schools from the field and methodology for these classes is controversial and contentious, both in terms of teaching, monitoring and organizational, is the perspective of values, training and systematization of public policy. Why the strategy Methodological Active School facing those classes appeared as a significant and exciting topic of research. Thus, it was aimed to apprehend the social representations of active school by teachers (s) to understand the extent to which these representations influence the acceptance and use of the program strategies. Perceiving and analyzing also the various factors related to the management, monitoring and training needs of (the) teachers as alternatives to make this meaningful action. The study focused 112 teachers (s), which for over a year, worked in the program in six municipalities in the micro-region of Rio Grande do Norte / RN - Areia Branca, Baraúna, Grossos, Mossoró, Serra do Mel and Tibau. From this perspective relied on Social Representation Theory and the Theory of the Central Core, attending to the subjectivity of the object searched, inserted in the psychosocial field of knowledge, we opted for multi-methodological approach, using quantitative and qualitative techniques. However, the highlight was a projective technique Free Association of Words from the term Active School is .... The words were systematized by EVOC program, and also applied semi-structured interviews, focusing specific issues that led to trace the socio-demographic profile of (the) participants and wider issues about the object of study. The evocations, justifications and interviews provided the basis for the analysis of the content that followed the steps: formation of the corpus, the composition of the analysis and categorization. The results show the representations an attitude of acceptance and positive appraisal of the participants to the Active School Program. At the core, these representations are objectified around the words "action", "learning", "autonomy" and "interaction". Based on the premise that the representations have a duty to guide the practices and behavior, one can see that the positive attitude of the group favors a systematic methodology and acceptance of the program, but we must look at the changes in management, training, monitoring of (the) teachers (s) and support to schools.

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This thesis is resulted of a research on propagated the social representations of constructivism in the Internet, which as had estimated basic the idea of Moscovici (1961) of that the media it has determinative paper in the popularization of the scientific theories, in formation e propagation of the social representations and in the construction of behaviors human beings. Understanding the Internet as latest space of circulation of social communications, therefore, privileged field (and still not explored) for studies of social representations, we choose this half midiático as investigative field of our research, it if it constitutes in the "great ocean of the new informational planet" (LEVY, 2000, p. 126), besides making possible the interaction with different forms of images, different individuals, different ' world ', configuring itself as important space of symbolic production e of analysis of the representational process in the world contemporary. Based in these questions, we trace as objective to analyze the circulating speech propagated on-line on the constructivism, searching to apprehend the social representations shared the respect. This objective was constructed in face of the insertion of the theory constructivist in the educational way has two decades more than, as well as of its consolidation as reference in different social contexts, mainly in midiático. The question that directed the research was: as this theory obtains to penetrate in some layers of our society, to influence the world readings e the behaviors of different people? That modifications it suffers in this trajectory and which the paper of the Internet in this process? The corpus of the research was constituted of the substances on the theory found in the Internet, in pages in Portuguese of Google, in the period of 27 of July of 2004 the 17 of August of 2004. The data they had been analyzed on the basis of the project of analysis of content elaborated for Moscovici (1961) and in the estimated theoreticians of the social communication, in special of the hypermedia. The results had disclosed that the Internet participates of determinative form in the process of popularization of the constructivism theory, not only spreading out its estimated theoretician- methodological for the domain public (diffusion), but propagating positive beliefs and images of its postulates (propagation) and using them it service of interests politicians e financiers (propaganda). The popularization of the constructivism in the Internet and social representations of this theory propagated configure one process in which the theory passes of pedagogical theoretical landmark for grief, assuming a commercial character extremely and the status of solution for problems of the education and the society, stirring up attitudes and behaviors in public, most general possible, that comes to take care of to the interests politicians e marketing. Recognizing the diversity, the permanent renewal of information and the negotiation of directions gifts in the Internet, as well as the innumerable ones forms of access to the information found by it, we consider results of the research as fruits of the inherent characteristics to this way midiático, to the time where we call the attention for relativity these results, for the plasticity of knowing them and sensible propagated on-line e for the great challenge that the hypermedia imposes to the study of communication phenomena, of the social representations and in educational quarrels and for the necessity of new research that they investigate the forms of socialization of the information and communication propitiated by hypermedia and its implications in the construction of the symbolic universes and in practical social

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This study aimed to understand the typical ideal of the nursing technician about the systematization of nursing care in the light of the theoretical framework of Alfred Schutz. It is a comprehensive phenomenological research, using the theoretical framework of Alfred Schutz. For the unveiling of the phenomenon (the typical ideal of the nursing technician about the systematization of nursing care), the search process was configured from the proposed guiding principles for a research methodology based on the work itself of Schutz held by Zeferino (2010) in his PhD. For data collection, we used the focus group technique, counting on the collaboration of thirteen practical nurses working in a university hospital in Rio Grande do Norte, who responded positively to the inclusion criteria: working in the study hospital, performing care direct to patients. Forty-four subjects showed interest in participating, being held a draw for selection of the research sample, consisting of 14 professionals, one of whom did not attend the gathering of data collection. The focus group, entitled "What I think about the systematization of nursing care", took place on February 15th, 2013, totaling 101 minutes. It was performed according to the Experiential Education Humanescent using building posters as projective technique, from the key question: "What is the systematization of nursing care for you?". In order to understand some of the biographical situation of the participants, a questionnaire was administered to study participants. From the agreement of the subjects, the focus group was recorded and photographed with the cooperation of one reporter and two other employees. We used Microsoft Word 2010 to perform the transcript of the meeting and Microsoft Excel 2010 for synthesizing the results via a spreadsheet. The study followed the ethical and legal principles that govern scientific research on humans, recommended in Resolution nº 196/96, it was approved by Opinion Embodied Ethics Committee in Research of UFRN (Federal University of Rio Grande do Norte), nº 98 424, of August 31th, 2012, CAAE No. 05906912.0.0000.5537. The analysis of the nursing staff speeches, along with the contemplation of their posters and their written descriptions, allowed from the guiding principles of Zeferino (2010), in light of the reference of Alfred Schutz, unveiling the typical ideal of nursing technicians about the systematization of nursing care, passing four themes: typing of the concept of systematization of nursing care; benefits, which resulted in the reasons to believe in the positivity of this working tool; experienced problems, revealing the world of everyday life of nursing professionals, and possibilities for improvement. It was concluded that the nursing technicians are unaware of the systematization of nursing care. However, they typify a very positive perception about the same, especially with regard to improvements that may foster care

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This study evaluates the level of accessibility for people with visual impairment (blindness and low vision) hotels in the city of Natal-RN, Brazil, and provides principles, guidelines and means of projective make hotels accessible, to promote comfort, autonomy and security of these people. We used a qualitative research methodology and quantitative trait descriptive, analytical and interpretive. Was taken as a base for field studies Ergonomic Analysis of Work, beginning with a study of the demands of accessibility of hotels and analyzing the modeling activity in these establishments through the application of interactional and observational techniques, such as film, photographic records, conversational actions and observation protocols. A protocol was developed and applied to evaluate the compliance of accessibility of hotels in the face of Brazilian technical standard NBR 9050 (2004). We used methods of Cognitive Task Analysis (CTA) associated with simulated activities to identify the processes of decision making and analyzing the observables of the activities performed by people with visual impairment (POS). Interviews were conducted with people who are blind and low vision in various cities in order to meet accessibility difficulties they faced in hotels and recommendations for improvement that they indicate. The mapping results showed that of 16 hotels 4 and 5 star studied in Natal-RN, reached only 7% of the 50 items of the protocol, while none of them reached 70% of the items. About the results obtained in simulated activities and analyzed from the ATC, we saw that the hotel where it was performed this step shows a need to adequately address the guests with visual impairments

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In the Einstein s theory of General Relativity the field equations relate the geometry of space-time with the content of matter and energy, sources of the gravitational field. This content is described by a second order tensor, known as energy-momentum tensor. On the other hand, the energy-momentum tensors that have physical meaning are not specified by this theory. In the 700s, Hawking and Ellis set a couple of conditions, considered feasible from a physical point of view, in order to limit the arbitrariness of these tensors. These conditions, which became known as Hawking-Ellis energy conditions, play important roles in the gravitation scenario. They are widely used as powerful tools for analysis; from the demonstration of important theorems concerning to the behavior of gravitational fields and geometries associated, the gravity quantum behavior, to the analysis of cosmological models. In this dissertation we present a rigorous deduction of the several energy conditions currently in vogue in the scientific literature, such as: the Null Energy Condition (NEC), Weak Energy Condition (WEC), the Strong Energy Condition (SEC), the Dominant Energy Condition (DEC) and Null Dominant Energy Condition (NDEC). Bearing in mind the most trivial applications in Cosmology and Gravitation, the deductions were initially made for an energy-momentum tensor of a generalized perfect fluid and then extended to scalar fields with minimal and non-minimal coupling to the gravitational field. We also present a study about the possible violations of some of these energy conditions. Aiming the study of the single nature of some exact solutions of Einstein s General Relativity, in 1955 the Indian physicist Raychaudhuri derived an equation that is today considered fundamental to the study of the gravitational attraction of matter, which became known as the Raychaudhuri equation. This famous equation is fundamental for to understanding of gravitational attraction in Astrophysics and Cosmology and for the comprehension of the singularity theorems, such as, the Hawking and Penrose theorem about the singularity of the gravitational collapse. In this dissertation we derive the Raychaudhuri equation, the Frobenius theorem and the Focusing theorem for congruences time-like and null congruences of a pseudo-riemannian manifold. We discuss the geometric and physical meaning of this equation, its connections with the energy conditions, and some of its several aplications.

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In this work we obtain the cosmological solutions and investigate the thermodynamics of matter creation in two diferent contexts. In the first we propose a cosmological model with a time varying speed of light c. We consider two diferent time dependence of c for a at Friedmann-Robertson- Walker (FRW) universe. We write the energy conservation law arising from Einstein equations and study how particles are created as c decreases with cosmic epoch. The variation of c is coupled to a cosmological Λ term and both singular and non-singular solutions are possible. We calculate the "adiabatic" particle creation rate and the total number of particles as a function of time and find the constrains imposed by the second law of thermodynamics upon the models. In the second scenario, we study the nonlinearity of the electrodynamics as a source of matter creation in the cosmological models with at FRW geometry. We write the energy conservation law arising from Einstein field equations with cosmological term Λ, solve the field equations and study how particles are created as the magnetic field B changes with cosmic epoch. We obtain solutions for the adiabatic particle creation rate, the total number of particles and the scale factor as a function of time in three cases: Λ = 0, Λ = constant and Λ α H2 (cosmological term proportional to the Hubble parameter). In all cases, the second law of thermodynamics demands that the universe is not contracting (H ≥ 0). The first two solutions are non-singular and exhibit in ationary periods. The third case studied allows an always in ationary universe for a suficiently large cosmological term

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Many astronomical observations in the last few years are strongly suggesting that the current Universe is spatially flat and dominated by an exotic form of energy. This unknown energy density accelerates the universe expansion and corresponds to around 70% of its total density being usually called Dark Energy or Quintessence. One of the candidates to dark energy is the so-called cosmological constant (Λ) which is usually interpreted as the vacuum energy density. However, in order to remove the discrepancy between the expected and observed values for the vacuum energy density some current models assume that the vacuum energy is continuously decaying due to its possible coupling with the others matter fields existing in the Cosmos. In this dissertation, starting from concepts and basis of General Relativity Theory, we study the Cosmic Microwave Background Radiation with emphasis on the anisotropies or temperature fluctuations which are one of the oldest relic of the observed Universe. The anisotropies are deduced by integrating the Boltzmann equation in order to explain qualitatively the generation and c1assification of the fluctuations. In the following we construct explicitly the angular power spectrum of anisotropies for cosmologies with cosmological constant (ΛCDM) and a decaying vacuum energy density (Λ(t)CDM). Finally, with basis on the quadrupole moment measured by the WMAP experiment, we estimate the decaying rates of the vacuum energy density in matter and in radiation for a smoothly and non-smoothly decaying vacuum

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This work presents the processes and the results of a research concerning the affectivity in children suffering from the Down´s Syndrome (DS). The relevance of the study is justified due to the need of the development of researches, in the area of psychological evaluation of people who suffers from Down´s Syndrome (DS), that are backed by the use of appropriate instruments for such purpose. The thematic discussed focuses the characteristics of the affectivity of children suffering from Down´s Syndrome. Affectivity, conceptually, is considered a wide phenomenon, including several aspects such as emotions, passions, anxiety, anguish, sadness, happiness and even the pleasure sensations and pain. The general objective of the study consisted of investigating the manifestation of the affectivity in children and young with Down´s Syndrome and the parents´ and educators´ perception concerning the expression of the affectivity in the behavior and in the social activities. The specific objectives were: to identify the parents' perceptions about the several manifestations of indicative behaviors of affectivity; to verify in the social atmosphere, outside home, through the teachers' perception, the several forms and intensities of the expression of the affectivity; and, to make possible the use of the technique of Zulliger (Z-test) in people with Down´s Syndrome. 70 (seventy) children and young with Down´s Syndrome participated in the research, in the age group from 04 to 26 years old, which are attended by Institutions of Paraíba and of Rio Grande do Norte. The instruments used were two questionnaires, applied with the parents and teachers, and the projective technique, Z-test, applied, individually, with the children and young with Down´s Syndrome. For analysis of the data of the questionnaires, the program Trideux-Mots was used, with the intention of selecting the main outstanding words for the parents and teachers concerning the expression of the children's affectivity and young with Down´s Syndrome. For so much, it was organized a database that was processed by that program and, soon after, interpreted through the Factorial Analysis by Correspondence (AFC), looking for to clear the modalities of presented answers in an organized way, through a graph. The data of the Z-test were analyzed, taking in consideration the need to characterize the aspects of the affectivity and the elaboration of specific norms for this sample type, through normalized scores. In agreement with the data presented by Tri-deux-Mots, it was observed that in the affective behavior and in the relationship with the other, home and in the school, the children and young with Down´s Syndrome they express your affectivity through positive and negative characteristics, in the same way that any other child that doesn't have to syndrome. The Z-test made possible initial elements to work with that population, however it is necessary that grow other researches with the intention of investigating the reason of the answers they present not the specific categories that you/they are related to the affectivity, since it was well-known the diversity of affective characteristics presented by the researched group

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It is undeniable that all the extraordinary technological advances in contemporary society have increased the severe patients expectation and quality of life, especially cancer patients. On the other hand, it is easily verifiable by many researches that it was not possible to advance in the same proportion in caring for the human experience of death. Much is said about the anguish of a man facing death, of cancer patients in terminal stage, about their families, and very little about the feelings, anxieties and ways of coping with the medical professional who deals with this situation, specifically the clinical oncologist. Little is known about the experience of the doctor who has learned to take death as an enemy to be defeated, and increasingly is compelled to live at length with his advertisement. However, we started to watch in recent years a growing interest of researchers in this issue. This study seeks to add to this interest in order to understand the experience of clinical oncologists that accompany dying patients, the meanings they attach to death, ways of coping and the implications for providing care. This is a qualitative study in which was used as a tool for data collection an in-depth interview with the projective using script and scenes. Gadameriana Hermeneutics was used for analysis and interpretation of narratives. The subjects were 10 clinical oncologists who work at two institutions from cancer treatments in the state of Rio Grande do Norte, chosen from a variation in the time working in the specialty (minimum of one year, even old ones). However, you can bring some initial results for the dialogue. It was found that the death is still a topic that causes many difficulties in the daily lives of these professionals, the choice for oncology involves dealing with death without preparation in medical education; being close to the patient in the final moment, supporting the family, coping with own pain of loss and the inability to heal. These are central elements of the narratives. We also have investment in medical training and continuing education in setting up a demand that permeates the discourse of participants. Being able to listen to the subjective world of clinical oncologists will support the work not only for them as other professionals who deal with patients with advanced cancer, providing evidence to understand to what extent the meanings attributed to its know-how before patients on the verge of death interfere with the production of care and allow identify coping strategies in everyday life of these professionals that hinder or facilitate coping with death, promote or preclude the care with others and with themselves. It is hoped that research can contribute to the field of knowledge about the know-how in clinical oncology and their terminal-care-death oncologist-patient relationships, bringing runways capable of promoting a better quality of care in the production of all involved in this process: professionals, patients and families

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The depression is one of the most common forms of getting ill nowaday. Due to the increase in incidence of depression cases registered worldwide, this theme has been the subject of important studies, especially regarding the symptomatological description and biological etiology of the disease. This research had the objective to understand the unique experience of depression experienced by people who recognize themselves in depression, under the focus of existential phenomenology of Martin Heidegger. To reach the proposed objective, individuals narratives interviews were conducted with four participants, starting from the triggering question, "from your experience, how is for you to being depressed?". The survey revealed that depression affects the whole person and is related to stressful life contexts. Depression was narrated as an experience of disempowerment and lack of self esteem and personal worth. The collaborators of the research referred to the depression from sad, angry, bored and pessimistic mood. The time is experienced as a restriction to the projective opening towards the possibilities of being in which the future is seen as catastrophic and the past lived as debt and guilt. The corporeality, in depression is experienced through the weight, fatigue and pains for no reason. The space is lived from the notion of fall and collapse. We also realized the desire for isolation and avoidance of social contact. Suicide is desired and represents the end of the suffering in life. The depression has proved, still, very stigmatized, because it is discredited and misunderstood. The stigma also addressed to the experience of hospitalization and the unsuitability to the socially imposed standards of beauty, which generates enough suffering to the depressed person. The medication was described based on its positive effects, as a balance and suffering reducer, but also as a producer of dependence. Were also identified according to the collaborators, traces of selfdemand, ordenality and being-for-others, characteristic of typus melancholicus. This study contributes to an understanding of the depression that goes beyond the merely biological perspective and symptomatology of the pathology. The investigation of the depressive experience, through the lens of Heidegger's phenomenology, showed us the phenomenon of the depression in their singularity, complexity and multiple meanings, showing the close relationship between the formation of the depression and the context of personal and social life of the participants

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In this work we propose a technique that uses uncontrolled small format aerial images, or SFAI, and stereohotogrammetry techniques to construct georeferenced mosaics. Images are obtained using a simple digital camera coupled with a radio controlled (RC) helicopter. Techniques for removing common distortions are applied and the relative orientation of the models are recovered using projective geometry. Ground truth points are used to get absolute orientation, plus a definition of scale and a coordinate system which relates image measures to the ground. The mosaic is read into a GIS system, providing useful information to different types of users, such as researchers, governmental agencies, employees, fishermen and tourism enterprises. Results are reported, illustrating the applicability of the system. The main contribution is the generation of georeferenced mosaics using SFAIs, which have not yet broadly explored in cartography projects. The proposed architecture presents a viable and much less expensive solution, when compared to systems using controlled pictures

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In this dissertation, after a brief review on the Einstein s General Relativity Theory and its application to the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological models, we present and discuss the alternative theories of gravity dubbed f(R) gravity. These theories come about when one substitute in the Einstein-Hilbert action the Ricci curvature R by some well behaved nonlinear function f(R). They provide an alternative way to explain the current cosmic acceleration with no need of invoking neither a dark energy component, nor the existence of extra spatial dimensions. In dealing with f(R) gravity, two different variational approaches may be followed, namely the metric and the Palatini formalisms, which lead to very different equations of motion. We briefly describe the metric formalism and then concentrate on the Palatini variational approach to the gravity action. We make a systematic and detailed derivation of the field equations for Palatini f(R) gravity, which generalize the Einsteins equations of General Relativity, and obtain also the generalized Friedmann equations, which can be used for cosmological tests. As an example, using recent compilations of type Ia Supernovae observations, we show how the f(R) = R − fi/Rn class of gravity theories explain the recent observed acceleration of the universe by placing reasonable constraints on the free parameters fi and n. We also examine the question as to whether Palatini f(R) gravity theories permit space-times in which causality, a fundamental issue in any physical theory [22], is violated. As is well known, in General Relativity there are solutions to the viii field equations that have causal anomalies in the form of closed time-like curves, the renowned Gödel model being the best known example of such a solution. Here we show that every perfect-fluid Gödel-type solution of Palatini f(R) gravity with density and pressure p that satisfy the weak energy condition + p 0 is necessarily isometric to the Gödel geometry, demonstrating, therefore, that these theories present causal anomalies in the form of closed time-like curves. This result extends a theorem on Gödel-type models to the framework of Palatini f(R) gravity theory. We derive an expression for a critical radius rc (beyond which causality is violated) for an arbitrary Palatini f(R) theory. The expression makes apparent that the violation of causality depends on the form of f(R) and on the matter content components. We concretely examine the Gödel-type perfect-fluid solutions in the f(R) = R−fi/Rn class of Palatini gravity theories, and show that for positive matter density and for fi and n in the range permitted by the observations, these theories do not admit the Gödel geometry as a perfect-fluid solution of its field equations. In this sense, f(R) gravity theory remedies the causal pathology in the form of closed timelike curves which is allowed in General Relativity. We also examine the violation of causality of Gödel-type by considering a single scalar field as the matter content. For this source, we show that Palatini f(R) gravity gives rise to a unique Gödeltype solution with no violation of causality. Finally, we show that by combining a perfect fluid plus a scalar field as sources of Gödel-type geometries, we obtain both solutions in the form of closed time-like curves, as well as solutions with no violation of causality