29 resultados para Decisões de investimento sob risco e incerteza
em Universidade Federal do Rio Grande do Norte(UFRN)
Resumo:
Leptospirosis is a worldwide zoonosis of considerable medical and economical importance that affects humans in both urban and rural contexts, as well as domestic animals and wild fauna. Leptospira interrogans is the causative agent and is transmitted to humans by indirect contact with contaminated soil or water. The clinical syndromes include sub clinical infection, self-limited anicteric febrile illness, and severe and potentially fatal illness, known as Weil´s syndrome. In developed countries, leptospirosis is related to occupational or recreational activities while in developing countries, outbreaks occur during floods. In those regions, traditional strategies to prevent the transmission are difficulties to be implemented because of costs and lack of community acceptance. In addition, no efficient vaccine is available for human use. Several studies have suggested that chemoprophylaxis with doxycycline pre and post-exposure may be effective to prevent leptospirosis. Leptospirosis has been reported in rural areas of the State of Rio Grande do Norte, Brazil since 1985 in rice farmers who present the anicteric illness. The disease cause great social and economics impact. The study was conducted in São Miguel where an epidemic of leptospirosis in rice farmers was reported. The main objective was to determine the efficacy of doxycycline in preventing Leptospira exposure. A taxa de soroprevalência de leptospirose na população estudada antes e após a colheita foi de 14,2% (n=22) e de 16.6% (n=27) respectivamente. Anti-Leptospira serology was determined for 61 subjects in two instances, pre and post-exposure to potential contaminated water. There was an increased risk of 29.0 per cent in acquiring infection for individuals that did not use doxycycline. In addition, an increased risk of 30.0 % observed in farmers who did not use protection when exposed to Leptospira. The adhesion to preventive chemoprophylaxis was 55.7%. Therefore doxycycline, under specific circunstances appears to be an effective alternative to protect against leptosprirosis infection. A large sample composed of individuals to adhere to preventive therapy is needed to define time, dosage and length of use of doxycycline in this area
Resumo:
This work demonstrates the importance of using tools used in geographic information systems (GIS) and spatial data analysis (SDA) for the study of infectious diseases. Analysis methods were used to describe more fully the spatial distribution of a particular disease by incorporating the geographical element in the analysis. In Chapter 1, we report the historical evolution of these techniques in the field of human health and use Hansen s disease (leprosy) in Rio Grande do Norte as an example. In Chapter 2, we introduced a few basic theoretical concepts on the methodology and classified the types of spatial data commonly treated. Chapters 3 and 4 defined and demonstrated the use of the two most important techniques for analysis of health data, which are data point processes and data area. We modelled the case distribution of Hansen s disease in the city of Mossoró - RN. In the analysis, we used R scripts and made available routines and analitical procedures developed by the author. This approach can be easily used by researchers in several areas. As practical results, major risk areas in Mossoró leprosy were detected, and its association with the socioeconomic profile of the population at risk was found. Moreover, it is clearly shown that his approach could be of great help to be used continuously in data analysis and processing, allowing the development of new strategies to work might increase the use of such techniques in data analysis in health care
Resumo:
Based on climate data and occurrence records, ecological niche models (ENM) are an important opportunity to identify areas at risk or vulnerable to biological invasion. These models are based on the assumption that there is a match between the climatic characteristic of native and invaded regions predicting the potential distribution of exotic species. Using new methods to measure niche overlap, we chose two exotic species fairly common in semi-arid regions of South America, Prosopis juliflora (Sw.) D.C. and Prosopis pallida (H. ; B. ex. Willd) HBK, to test the climate matching hypothesis. Our results indicate that both species occur with little niche overlap in the native region while the inverse pattern is observed in the invaded region on South America, where both species occur with high climatic overlap. Maybe some non-climate factor act limiting the spread of P. pallida on the native range. We believe that a founder effect can explain these similarities between species niche in the invaded region once the seeds planted in Brazil came from a small region on the Native range (Piura in Peru), where both species occur sympatric. Our hypothesis of a founder effect may be evident when we look at the differences between the predictions of the models built in the native and invaded ranges. Furthermore, our results indicate that P. juliflora shows high levels of climate matching between native and invaded ranges. However, conclusions about climate matching of P. pallida should be taken with caution. Our models based on climatic variables provide multiple locations suitable for occurrence of both species in regions where they still don t have occurrence records, including places of high interest for conservation.
Resumo:
The game industry has been experiencing a consistent increase in production costs of games lately. Part of this increase refers to the current trend of having bigger, more interactive and replayable environments. This trend translates to an increase in both team size and development time, which makes game development a even more risky investment and may reduce innovation in the area. As a possible solution to this problem, the scientific community is focusing on the generation of procedural content and, more specifically, on procedurally generated levels. Given the great diversity and complexity of games, most works choose to deal with a specific genre, platform games being one of the most studied. This work aims at proposing a procedural level generation method for platform/adventure games, a fairly more complex genre than most classic platformers which so far has not been the subject of study from other works. The level generation process was divided in two steps, planning and viusal generation, respectively responsible for generating a compact representation of the level and determining its view. The planning stage was divided in game design and level design, and uses a goaloriented process to output a set of rooms. The visual generation step receives a set of rooms and fills its interior with the appropriate parts of previously authored geometry
Resumo:
The acceleration of technological change and the process of globalization has intensified competition and the need for new products (goods and services), resulting in growing concern for organizations in the development of technological, economic and social advances. This work presents an overview of the development of wind energy-related technologies and design trends. To conduct this research, it is (i) a literature review on technological innovation, technological forecasting methods and fundamentals of wind power; (ii) the analysis of patents, with the current technology landscape studied by means of finding information in patent databases; and (iii) the preparation of the map of technological development and construction of wind turbines of the future trend information from the literature and news from the sector studied. Step (ii) allowed the study of 25 644 patents between the years 2003-2012, in which the US and China lead the ranking of depositors and the American company General Electric and the Japanese Mitsubishi stand as the largest holder of wind technology. Step (iii) analyzed and identified that most of the innovations presented in the technological evolution of wind power are incremental product innovations to market. The proposed future trends shows that the future wind turbines tend to have a horizontal synchronous shaft, which with the highest diameter of 194m and 164m rotor nacelle top, the top having 7,5MW generation. The materials used for the blades are new materials with characteristics of low density and high strength. The towers are trend with hybrid materials, uniting the steel to the concrete. This work tries to cover the existing gap in the gym on the use of technological forecasting techniques for the wind energy industry, through the recognition that utilize the patent analysis, analysis of scientific articles and stories of the area, provide knowledge about the industry and influencing the quality of investment decisions in R & D and hence improves the efficiency and effectiveness of wind power generation
Resumo:
Leptospirosis is a worldwide zoonosis of considerable medical and economical importance that affects humans in both urban and rural contexts, as well as domestic animals and wild fauna. Leptospira interrogans is the causative agent and is transmitted to humans by indirect contact with contaminated soil or water. The clinical syndromes include sub clinical infection, self-limited anicteric febrile illness, and severe and potentially fatal illness, known as Weil´s syndrome. In developed countries, leptospirosis is related to occupational or recreational activities while in developing countries, outbreaks occur during floods. In those regions, traditional strategies to prevent the transmission are difficulties to be implemented because of costs and lack of community acceptance. In addition, no efficient vaccine is available for human use. Several studies have suggested that chemoprophylaxis with doxycycline pre and post-exposure may be effective to prevent leptospirosis. Leptospirosis has been reported in rural areas of the State of Rio Grande do Norte, Brazil since 1985 in rice farmers who present the anicteric illness. The disease cause great social and economics impact. The study was conducted in São Miguel where an epidemic of leptospirosis in rice farmers was reported. The main objective was to determine the efficacy of doxycycline in preventing Leptospira exposure. A taxa de soroprevalência de leptospirose na população estudada antes e após a colheita foi de 14,2% (n=22) e de 16.6% (n=27) respectivamente. Anti-Leptospira serology was determined for 61 subjects in two instances, pre and post-exposure to potential contaminated water. There was an increased risk of 29.0 per cent in acquiring infection for individuals that did not use doxycycline. In addition, an increased risk of 30.0 % observed in farmers who did not use protection when exposed to Leptospira. The adhesion to preventive chemoprophylaxis was 55.7%. Therefore doxycycline, under specific circunstances appears to be an effective alternative to protect against leptosprirosis infection. A large sample composed of individuals to adhere to preventive therapy is needed to define time, dosage and length of use of doxycycline in this area
Resumo:
The objective is to analyze the relationship between risk and number of stocks of a portfolio for an individual investor when stocks are chosen by "naive strategy". For this, we carried out an experiment in which individuals select actions to reproduce this relationship. 126 participants were informed that the risk of first choice would be an asset average of all standard deviations of the portfolios consist of a single asset, and the same procedure should be used for portfolios composed of two, three and so on, up to 30 actions . They selected the assets they want in their portfolios without the support of a financial analysis. For comparison we also tested a hypothetical simulation of 126 investors who selected shares the same universe, through a random number generator. Thus, each real participant is compensated for random hypothetical investor facing the same opportunity. Patterns were observed in the portfolios of individual participants, characterizing the curves for the components of the samples. Because these groupings are somewhat arbitrary, it was used a more objective measure of behavior: a simple linear regression for each participant, in order to predict the variance of the portfolio depending on the number of assets. In addition, we conducted a pooled regression on all observations by analyzing cross-section. The result of pattern occurs on average but not for most individuals, many of which effectively "de-diversify" when adding seemingly random bonds. Furthermore, the results are slightly worse using a random number generator. This finding challenges the belief that only a small number of titles is necessary for diversification and shows that there is only applicable to a large sample. The implications are important since many individual investors holding few stocks in their portfolios
Resumo:
Desde a criação da tecnologia e do seu uso pelas empresas, a relação custo e benefício nem sempre foi bem elucidada tanto para os responsáveis pela área de tecnologia quanto para a alta direção. Mas, apesar disto, cada vez mais as organizações investem maciçamente em tecnologia, esperando que esta seja a solução para diversos problemas. Por isto, esta questão tem se tornado crucial para o processo de tomada de decisões, visto que investimentos nesta área costumam ser dispendiosos e, na atual conjuntura, estas análises precisam ser extremamente criteriosas para que se miniminizem as possibilidades de insucesso dos projetos, principalmente numa economia estabilizada e de concorrência acirrada. Uma das alternativas que as empresas têm buscado para atingir o sucesso e correr menos riscos é a terceirização da área de TI. Partindo desta visão, a presente dissertação tem por objetivo realizar uma investigação sobre a terceirização dos serviços de TI em todos os seus aspectos, isto é, desde a sua motivação, serviços efetivamente terceirizados, vantagens, desvantagens e possíveis obstáculos, a visão do alinhamento estratégico da TI, os processos de gestão de contratos e formas de controle e, por fim, tendências futuras. Trata-se de uma pesquisa de múltiplos casos, envolvendo franquias do Sistema Coca-Cola no Brasil. O estudo apresenta uma pesquisa bibliográfica sobre o processo de tomada de decisão empresarial, a análise de investimentos, a gestão e a terceirização da TI, o que permitem definir as dimensões de análise da pesquisa. Na pesquisa de campo foram entrevistados os gerentes da área de TI, nas cidades de Brasília-DF, Goiânia-GO e Ribeirão Preto-SP. A pesquisa de campo permitiu identificar como as mesmas avaliam seus investimentos em TI, como esta área é gerenciada, o que as levou a optar pela terceirização e como os processos terceirizados afetam a organização. Por se tratar de uma pesquisa qualitativa, optou-se por analisar comparativamente as três organizações. Com a realização deste estudo, obtiveram-se, como principais resultados, que as organizações estão utilizando a terceirização em TI para focar no negócio principal e, mesmo encontrando diversas desvantagens, inclusive com relação a custos, acreditam que os benefícios justificam. Ainda identificaram-se alguns obstáculos internos para a terceirização, principalmente quanto ao receio de se perder a inteligência do negócio. O acompanhamento dessas atividades terceirizadas é realizado pela equipe interna e por critérios estruturados, onde se verificam os níveis de serviço
Resumo:
The objective is to analyze the relationship between risk and number of stocks of a portfolio for an individual investor when stocks are chosen by "naive strategy". For this, we carried out an experiment in which individuals select actions to reproduce this relationship. 126 participants were informed that the risk of first choice would be an asset average of all standard deviations of the portfolios consist of a single asset, and the same procedure should be used for portfolios composed of two, three and so on, up to 30 actions . They selected the assets they want in their portfolios without the support of a financial analysis. For comparison we also tested a hypothetical simulation of 126 investors who selected shares the same universe, through a random number generator. Thus, each real participant is compensated for random hypothetical investor facing the same opportunity. Patterns were observed in the portfolios of individual participants, characterizing the curves for the components of the samples. Because these groupings are somewhat arbitrary, it was used a more objective measure of behavior: a simple linear regression for each participant, in order to predict the variance of the portfolio depending on the number of assets. In addition, we conducted a pooled regression on all observations by analyzing cross-section. The result of pattern occurs on average but not for most individuals, many of which effectively "de-diversify" when adding seemingly random bonds. Furthermore, the results are slightly worse using a random number generator. This finding challenges the belief that only a small number of titles is necessary for diversification and shows that there is only applicable to a large sample. The implications are important since many individual investors holding few stocks in their portfolios
Resumo:
Estudar a incidência e fatores de risco (tempo de doença e presença de hipertensão arterial sistêmica) para retinopatia diabética em 1002 pacientes encaminhados pelo Programa de Diabetes do Hospital Universitário Onofre Lopes no período de 1992 – 1995. Métodos: Estudo retrospectivo de pacientes com diagnóstico de diabetes mellitus encaminhados ao Setor de Retina do Departamento de Oftalmologia pelo Programa de Diabetes do Hospital Universitário e submetido, sob a supervisão do autor, a exame oftalmológico, incluindo medida da acuidade visual corrigida (tabela de Snellen), biomicroscopia do segmento anterior e posterior, tonometria de aplanação e oftalmoscopia binocular indireta sob midríase(tropicamida 1% + fenilefrina 10%). Foi realizada análise dos prontuários referente ao tempo de doenças e diagnostico clínico de hipertensão arterial sistêmica. Resultados: Dos 1002 diabéticos examinados (em 24 deles a fundoscopia foi inviável), 978 foram separados em 4 grupos: sem retinopatia diabética (SRD), 675 casos (69,01%); com retinopatia diabética não proliferativa (RDNP), 207 casos (21,16%); com retinopatia diabética proliferativa (RDP), 70 casos (7,15%); e pacientes já fotocoagulados (JFC), 26 casos (2,65%). Do total, 291 eram do sexo masculino (29%) e 711 do sexo feminino (71%). Os 4 grupos foram ainda avaliados quanto ao sexo, a faixa etária, a acuidade visual, tempo de doença, presença de catarata e hipertensão arterial sistêmica e comparados entre si. Com relação ao tipo de diabetes, 95 eram do tipo I (9,4%), 870 pacientes eram do tipo II (86,8%), e em 37 casos(3,7%) o tipo de diabetes não foi determinado. Conclusões: Comprovou-se que os pacientes com maior tempo de doença tinham maior probabilidade de desenvolver retinopatia diabética, e que a hipertensão arterial sistêmica não constituiu fator de risco em relação à diminuição da acuidade visual nos pacientes hipertensos
Resumo:
When a company desires to invest in a project, it must obtain resources needed to make the investment. The alternatives are using firm s internal resources or obtain external resources through contracts of debt and issuance of shares. Decisions involving the composition of internal resources, debt and shares in the total resources used to finance the activities of a company related to the choice of its capital structure. Although there are studies in the area of finance on the debt determinants of firms, the issue of capital structure is still controversial. This work sought to identify the predominant factors that determine the capital structure of Brazilian share capital, non-financial firms. This work was used a quantitative approach, with application of the statistical technique of multiple linear regression on data in panel. Estimates were made by the method of ordinary least squares with model of fixed effects. About 116 companies were selected to participate in this research. The period considered is from 2003 to 2007. The variables and hypotheses tested in this study were built based on theories of capital structure and in empirical researches. Results indicate that the variables, such as risk, size, and composition of assets and firms growth influence their indebtedness. The profitability variable was not relevant to the composition of indebtedness of the companies analyzed. However, analyzing only the long-term debt, comes to the conclusion that the relevant variables are the size of firms and, especially, the composition of its assets (tangibility).This sense, the smaller the size of the undertaking or the greater the representation of fixed assets in total assets, the greater its propensity to long-term debt. Furthermore, this research could not identify a predominant theory to explain the capital structure of Brazilian
Resumo:
The Oil industry in Brazil has gone through several stages during the economical, political and social historical process. However, the significative changes have happened in the last fifteen years, due to market opening arising from the relaxation of the state monopoly over the Oil deposits and its derivatives. The edition of the Constitutional Amendment #9, changing the first paragraph of the 177th item of the Federal Constitution, marked the end of a stiffness about the monopoly that the Brazilian state kept in relation to the exploration and research of Oil and Gas. The economical order was fundamental to actualize the idea contained in the #9 Amendment, since its contents has the power to set up measures to be adopted by public power in order to organize the economical relations from a social viewpoint. The new brazilian Oil scenery, called pre-salt, presents itself in a way to amaze the economical markets, in addition to creating a new perspective to the social sector. This work will identify, in this new scenario, the need for change in the legal system. Nevertheless, this subject must not be treated in a thoughtless way: being an exhaustible good, we shall not forget that the future generations also must benefit from the exploration of natural resources recently discovered. The settlement of a new regulatory mark, including the change in the concession contract model to production and sharing is one of the suggested solutions as a bill in the National Congress, in an attempt to ensure the sovereignty of the nation. The constitutionality of a new regulatory mark is questioned, starting from an analysis of the state monopoly, grounding the comprehnsions in the brazilian constitutions, the relevance of the creation of Petrobras for self-assertion of the state about the monopoly of Oil and derivatives, and its posture after the Constitutional Amendment nº 9 (1995), when a company stops having control of the state monopoly, beginning to compete in a fairly way with other companies. The market opening and private initiative are emphasized from the viewpoint of the Constitutional Principles of the Economical and Social Order. The relaxation of the monopoly regarding the exploratory activity in the Federal Constitution doesn't deprive from the Union the ownerships of underground goods, enabling to this federal entity to contract, directly or by concession of exploration of goods, to state-owned or private companies. The existing oil in the pre-salt layer transforms the scenario from very high risk to low risk, which gives the Union the possibility of defining another way of exploring this resources in the best interests of the Public Administration
Resumo:
The present dissertation, elaborated is based on the deductive method, through the use of the General Theory of Resources concepts, by the main types of judgments existing in the Code of Civil Procedure, the interlocutory judgment and sentence, as well as the features and effects that challenge these decisions, we sought to identify on this theme one of the greatest evils facing the justice system in the world, which is the processing delays. This slowness in adjudication affects seriously the principle of effectiveness, one of the postulates of procedural law and society as a whole. Thus, the use of tort serves to fight the interlocutory decision and appeal which challenges the judge`s ruling. It is a resource for excellence in appellate system as it meets with the most awaited decision of the process. In weighing the importance of the appeal that seeks to oppose the court decision today by the numerous reforms that the procedural system has been through, it has ended up to transform the process ineffective or inconsistent, for it is much easier to have efficacy in a interlocutory decision for preliminary injunction than by judgment on the merits of the judge. This is due to the prevision of the resources and their effect to those decisions. That is, the interlocutory decision involves interlocutory appeal only in the devolved effect, allowing its provisional execution, and the sentence has as recourse to appeal the double effect, remanding and suspension, which necessarily prevents its provisional execution. But it undeniably shows a paradox, because as to give effect to a measure that is based on a mere probability by a summary cognition, partial and superficial, and stop it on a decision by a court that is closer to the truth and sure, for a full and depleting cognition? It is seriously affect the principle of effectiveness. Therefore, starting from this ineffectiveness, sought to defend the solution of this problem with the approval of the bill n. º 3.605/2004 or the new Code of Civil Procedure project that modifies the general rule the effects of appeal. That is, remanding and suspensive, as to merely remanding effect to and thereby enable the provisional execution of the judgment of the court of the first degree of jurisdiction, giving effectiveness and enhancing the decision of the magistrate, making a fair distribution of time in the process and better guaranteed principle of access to justice
Resumo:
The demographic growth press environments that are more susceptible to perturbations, like riparian areas, without knowing about the effects of replacing these natural environments by different land uses on soil quality and, consequently, on watershed. The study of soil quality has evolved as an important tool for soil sustainable management of this component of the biosphere that affects aquatic and terrestrial ecosystems functions. Thus, physical and chemical soil proprieties were measured to assess soil quality under different land uses (agricultural, pasture, urban, industrial and natural vegetation,) in the riparian zone of Extremoz Lake, an important human water source, evaluating whether the soil offers potential risk to water pollution. Data were subjected to descriptive statistics and Principal Component Analysis (PCA). The results showed negative changes in soil quality such as alkalinization and increase in P, Pb, Mn and Zn contents in most anthropized areas. The sandy texture and low organic matter content in all soils showed the fragility of the soil to erosion and leaching of elements in excess to water bodies, evidencing that this soils has potential to diffuse contaminants. Conservative management of soil is necessary to provide an adequate ecological state in riparian zones of the Extremoz Lake, thus allowing controlling and buffering diffuse sources of pollution to this important water supply source
Resumo:
This research objectify to analyze the effects of minimum wage recovery in the household consumption in the Brazil, northeastern region of the Brazil and the state of the Rio Grande do Norte, in the period of 1995 to 2011. This is because the search for the strengthening of the internal market, via incentive policies to private demand has assumed prominence in the Government agenda. Thus, under the justification of the fierce debate about the effectiveness of countercyclical policies of Brazil, in view of the recent economic crisis, aims to: 1) retake the theoretical debate and, to a certain extent, the evolution of the theory of household consumption, as well as some conclusions about their connection with the minimum wage; 2) to describe the experiences and the effects of this legislation in economic history, with emphasis on the Brazilian case; 3) to present some of the available statistics to research bases, with attention to the specifics of each and the empirical results found for consumption in Brazil; 4) to estimate the effects of minimum wage variation in household consumption in Brazil (BR), northeast (NE) and Rio Grande do Norte (RN). From this, in order to quantify this relationship, makes inferences from the effects of the wage bill and the minimum wage on consumption, in quarterly series (with ad hoc adjustment from the "weights" of each quarter), from classic model of multiple linear regression. The hypothesis is that released: increments in income, derived from the policy of minimum wage recovery will influence directly the household consumption. However, when comparing the results between the units analyzed, the expressiveness of the northeastern families of Brazil and Rio Grande do Norte families front national dynamics with income linked to this floor, drives most significant impacts spending decisions in NE and RN, thus reducing regional disparities in the consumer. The results indicate contrary evidence, because while for the BR a unitary variation in minimum wage increases the consumption in units monetary 1.28, to the NE and RN these parameters are respectively 1.05 and 1.09