396 resultados para Bandos mistos


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Brazil is internationally acknowledged for its renewable sources, most notably, hydroelectric power plant projects which correspond to 65% of electricity production supply to the National Interconnected System. The main question behind this research is: what are the weights and the relative importance of the variables which have influence on the decision making process for the expansion of hydroelectric generation projects in Parana? The main objective is to propose a multi-criteria decision procedure, in association with water sources options that take into consideration the weight and relative importance of the alternatives having influence on the decision by enterprises in the generation of electricity in the state of Paraná. As far as the approach to the problem is concerned, this research can be classified as having mixed methodologies, applying Content Analysis, Delphi technique and the Analytic Hierarchy Process. Following Delphi methodology, a group of 21 was selected for data collection, all of those linked to Paranaense hydroelectricity market. And the main result was the construction of a decision tree in which it was possible to identify the importance and relative weight of the elements associated with the four dimensions of energy. In environmental dimension, the highest relative weight was placed on the loading capacity of Parana system; the economic dimension, the amortization of investment; in social dimension, the generation of direct work places and in institutional dimension, the availability of suitable sources of financing. Policy makers and business managers make their decisions based on specific criteria related to the organization segment, market information, economic and political behavior among other indicators that guide them in dealing with the typical tradeoffs of projects in hydropower area. The results obtained in the decision tree show that the economic bias is still the main factor in making investment decisions. However, environmental impacts on the State loading capacity, income generation, providing opportunities for direct as well as indirect jobs. And at an institutional level, the absence of funding sources show that the perception of experts is focused on other issues beyond the logic behind development per se. The order of priority of variables in this study indicates that in the current environment of uncertainty in the Brazilian economy as many variables must be analyzed and compared in order to optimize the scarce resources available to expand local development in relation to Paranaense water matrix.

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In this work, the relationship between diameter at breast height (d) and total height (h) of individual-tree was modeled with the aim to establish provisory height-diameter (h-d) equations for maritime pine (Pinus pinaster Ait.) stands in the Lomba ZIF, Northeast Portugal. Using data collected locally, several local and generalized h-d equations from the literature were tested and adaptations were also considered. Model fitting was conducted by using usual nonlinear least squares (nls) methods. The best local and generalized models selected, were also tested as mixed models applying a first-order conditional expectation (FOCE) approximation procedure and maximum likelihood methods to estimate fixed and random effects. For the calibration of the mixed models and in order to be consistent with the fitting procedure, the FOCE method was also used to test different sampling designs. The results showed that the local h-d equations with two parameters performed better than the analogous models with three parameters. However a unique set of parameter values for the local model can not be used to all maritime pine stands in Lomba ZIF and thus, a generalized model including covariates from the stand, in addition to d, was necessary to obtain an adequate predictive performance. No evident superiority of the generalized mixed model in comparison to the generalized model with nonlinear least squares parameters estimates was observed. On the other hand, in the case of the local model, the predictive performance greatly improved when random effects were included. The results showed that the mixed model based in the local h-d equation selected is a viable alternative for estimating h if variables from the stand are not available. Moreover, it was observed that it is possible to obtain an adequate calibrated response using only 2 to 5 additional h-d measurements in quantile (or random) trees from the distribution of d in the plot (stand). Balancing sampling effort, accuracy and straightforwardness in practical applications, the generalized model from nls fit is recommended. Examples of applications of the selected generalized equation to the forest management are presented, namely how to use it to complete missing information from forest inventory and also showing how such an equation can be incorporated in a stand-level decision support system that aims to optimize the forest management for the maximization of wood volume production in Lomba ZIF maritime pine stands.

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Es bien conocido que los primeros tribunales de la nueva Inquisición fueron establecidos por Fernando e Isabel en Andalucía, tanto en Sevilla como en Córdoba. Su introducción fue, por supuesto, el resultado de un claro propósito de lograr la ortodoxia religiosa entre los cristianos de origen judío los llamados «cristianos nuevos» o conversos. Pero el contexto político también influyó en la nueva institución porque contribuyó a asegurar el régimen de Isabel tras la amenaza que había representado su rival Juana “La- Beltraneja” y su marido portugués, al tiempo que podía servir para controlar mejor los conflictos entre «bandos», especialmente en Andalucía. Con todo, no debería pensarse que la Inquisición y sus horrores fueron una cuestión solamente atribuible a España. Por el contrario, tuvo sus precedentes y paralelos en otros países europeos, entre ellos Francia, Italia e Inglaterra.

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Ceramics materials have good properties including chemical stability, high hardness and wear resistance. Moreover, due to its fragility, can suffer failure under relatively low levels of tension. Actually zirconia is the material of choice in metal free dental prostheses used in dentistry due its inertia in physiological environment, good bending strength, hardness and fracture toughness. The alumina and mixed tungsten and titanium carbides additions, acting as reinforcement elements in the zirconia matrix, have as their main objective the improvement of mechanical properties of this material. In this work, samples of zirconia, zirconia with 30% wt of alumina and zirconia with 30% wt mixed carbides were analyzed. The samples were sintered by uniaxial hot pressing on 30 MPa pressure, for 1 hour in an argon atmosphere. They were physically characterized by porosity and density measurements, and mechanically by 3-points bending strength and Vickers microhardness. The X-ray diffraction was used for the phase identifications and microstructure was examined by scanning electron microscopy (SEM). The addition of mixed carbides as reinforcement elements in zirconia matrix provides improvements in all properties analyzed in this work. The alumina addition has dropped the zirconia strength, although it caused improvement in other properties

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The development and study of detectors sensitive to flammable combustible and toxic gases at low cost is a crucial technology challenge to enable marketable versions to the market in general. Solid state sensors are attractive for commercial purposes by the strength and lifetime, because it isn t consumed in the reaction with the gas. In parallel, the use of synthesis techniques more viable for the applicability on an industrial scale are more attractive to produce commercial products. In this context ceramics with spinel structure were obtained by microwave-assisted combustion for application to flammable fuel gas detectors. Additionally, alternatives organic-reducers were employed to study the influence of those in the synthesis process and the differences in performance and properties of the powders obtained. The organic- reducers were characterized by Thermogravimetry (TG) and Derivative Thermogravimetry (DTG). After synthesis, the samples were heat treated and characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), analysis by specific area by BET Method and Scanning Electron Microscopy (SEM). Quantification of phases and structural parameters were carried through Rietveld method. The methodology was effective to obtain Ni-Mn mixed oxides. The fuels influenced in obtaining spinel phase and morphology of the samples, however samples calcined at 950 °C there is just the spinel phase in the material regardless of the organic-reducer. Therefore, differences in performance are expected in technological applications when sample equal in phase but with different morphologies are tested

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The mixed metal oxides constitute an important class of catalytic materials widely investigated in different fields of applications. Studies of rare earth nickelates have been carried by several researchers in order to investigate the structural stability afforded by oxide formed and the existence of catalytic properties at room temperature. So, this study aims synthesize the nanosized catalyst of nickelate of lanthanum doped with strontium (La(1-x)SrxNiO4-d; x = 0,2 and 0,3), through the Pechini method and your characterization for subsequent application in the desulfurization of thiophene reaction. The precursor solutions were calcined at 300ºC/2h for pyrolysis of polyester and later calcinations occurred at temperatures of 500 - 1000°C. The resulting powders were characterized by thermogravimetric analysis (TG / DTG), surface area for adsorption of N2 by BET method, X-ray diffraction (XRD), scanning electron microscopy (HR_SEM) and spectrometry dispersive energy (EDS). The results of XRD had show that the perovskites obtained consist of two phases (LSN and NiO) and from 700ºC have crystalline structure. The results of SEM evidenced the obtainment of nanometric powders. The results of BET show that the powders have surface area within the range used in catalysis (5-50m2/g). The characterization of active sites was performed by reaction of desulfurization of thiophene at room temperature and 200ºC, the relation F/W equal to 0,7 mol h-1mcat -1. The products of the reaction were separated by gas chromatography and identified by the selective detection PFPD sulfur. All samples had presented conversion above 95%

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Tese (doutorado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Departamento de Enfermagem, Programa de Pós-Graduação em Enfermagem, 2015.

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Doutoramento em Gestão.

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The materials engineering includes processes and products involving several areas of engineering, allowing them to prepare materials that fulfill the needs of various new products. In this case, this work aims to study a system composed of cement paste and geopolymers, which can contribute to solving an engineering problem that directly involves the exploitation of oil wells subject to loss of circulation. To correct it, has been already proposed the use of granular materials, fibers, reducing the drilling fluid or cement paste density and even surface and downhole mixed systems. In this work, we proposed the development of a slurry mixed system, the first was a cement-based slurry and the second a geopolymer-based slurry. The cement-based slurry was formulated with low density and extenders, 12.0 ppg (1.438 g/cm ³), showing great thixotropic characteristics. It was added nano silica at concentrations of 0.5, 1.0 and 1.5 gps (66.88, 133.76 and 200.64 L/m3) and CaCl2 at concentrations of 0.5, 1, 0 and 1.5%. The second system is a geopolymer-based paste formulated from molar ratios of 3.5 (nSiO2/nAl2O3), 0.27 (nK2O/nSiO2), 1.07 (nK2O/nAl2O3) and 13.99 (nH2O/nK2O). Finally, we performed a mixture of these two systems, for their application for correction of circulation lost. To characterize the raw materials, XRD, XRF, FTIR analysis and titration were performed. The both systems were characterized in tests based on API RP10B. Compressive strength tests were conducted after curing for 24 hours, 7 and 28 days at 58 °C on the cement-based system and the geopolymer-based system. From the mixtures have been performed mixability tests and micro structural characterizations (XRD, SEM and TG). The results showed that the nano silica, when combined with CaCl2 modified the rheological properties of the cement slurry and from the concentration of 1.5 gpc (200.64 L / m³) it was possible to obtain stable systems. The system mixture caused a change in the microstructure of the material by favoring the rate of geopolymer formation to hinder the C3S phase hydration, thus, the production of CSH phases and Portlandite were harmed. Through the mixability tests it can be concluded that the system, due to reduced setting time of the mixture, can be applied to plug lost circulation zones when mixed downhole

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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Humanas, Departamento de Serviço Social, Programa de Pós-Graduação em Política Social, 2016.

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Os sistemas de ventilação assumem uma grande importância no consumo de energia de climatização e na definição das condições higrotérmicas e da qualidade do ar interior dos edifícios. São absolutamente necessários para garantir níveis adequados de renovação do ar interior. Em Portugal, nos edifícios multifamiliares, recorre-se essencialmente a sistemas de ventilação natural, de exaustão mecânica ou mistos. No entanto, dificilmente se consegue aquilatar convenientemente qual a correspondência entre o sistema de ventilação instalado e a taxa de ventilação atingida com o mesmo. Neste artigo, através de simulação recorrendo ao software CONTAM e com base em dados experimentais da permeabilidade ao ar dos dispositivos de ventilação, realiza-se uma análise de sensibilidade variando alguns dos parâmetros mais significativos nos sistemas de ventilação, tais como: perda de carga das grelhas de admissão, permeabilidade ao ar da caixilharia e caudais de extração na cozinha. A simulação anual dos fluxos de ar recorre a condições ambientais representativas do clima continental português (quatro cidades) e a subdivisão para as estações de aquecimento e arrefecimento, envolve também a produção de poluentes internos (CO2 e vapor de água). Com a simulação, obteve-se, nomeadamente, para um apartamento tipo, as taxas de ventilação, os fluxos de ar de admissão e exaustão, os teores dos poluentes, pontualmente ou em termos médios. As conclusões mais significativas a retirar das simulações são: a baixa permeabilidade ao ar da envolvente leva a reduções nas renovações horárias próximas do limite mínimo estabelecido regulamentarmente; a ventilação mecânica contínua na cozinha, a existência de uma grelha de admissão na cozinha, com abertura aquando dos caudais máximos, e o fecho das portas dos compartimentos de serviços reduz significativamente os teores de poluentes.

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Introdução: A perda transitória da consciência e tónus postural seguido de rápida recuperação é definida como síncope. Tem sido dada atenção a uma síncope de origem central com descida da pressão sistémica conhecida por síncope vasovagal (SVV). Objetivos: A análise da variabilidade da frequência cardíaca (HRV) é uma das principais estratégias para estudar a SVV através de protocolos padrão (por exemplo tilt test). O principal objetivo deste trabalho é compreender a importância relativa de diversas variáveis, tais como pressão arterial diastólica e sistólica, (dBP) e (sBP), volume sistólico (SV) e resistência periférica total (TPR) na HRV. Métodos: Foram usados modelos estatísticos mistos para modelar o comportamento das variáveis acima descritas na HRV. Analisaram-se mais de mil e quinhentas observações de quatro pacientes com SVV, previamente testados com análise espectral clássica para a fase basal (LF/HF=3.01) e fases de tilt (LF/HF=0.64), indicando uma predominância vagal no período tilt. Resultados: O modelo 1 revelou o papel importante da dBP e uma baixa influência de SV, na fase de tilt, relativos à HRV. No modelo 2 a TPR revelou uma baixa influência na HRV na fase de tilt entre os pacientes. Conclusões: Verificou-se que a HRV é influenciada por um conjunto de variáveis fisiológicas, cuja contribuição individual pode ser usada para compreender as flutuações cardíacas. O uso de modelos estatísticos salientou a importância de estudar o papel da dBP e SV na SVV.

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Esta dissertação está relacionada com as isenções previstas no sistema fiscal português, mais concretamente com as isenções previstas no Código do IVA e que abrangem as operações imobiliárias. Não obstante, o facto das isenções, no caso em específico, relativas à locação e à transmissão dos bens imóveis, violarem a estrutura base do IVA, vamos abordar a possibilidade de renunciar às mesmas e os procedimentos e obrigações que lhe estão subjacentes, pois as isenções ao serem aplicadas quebram o normal funcionamento do sistema. A renúncia à isenção permite ao sujeito passivo regressar ao normal funcionamento do imposto sobre o valor acrescentado, repondo as características subjacentes ao sistema do IVA. Ao longo do trabalho vamos estudar o nascimento do imposto, a sua introdução em Portugal e o seu âmbito de aplicação, ou seja, a incidência. Relativamente às isenções nas locações de imóveis vamos analisar os contratos de locação simples (“paredes nuas”), os mistos (para além da locação englobam prestações de serviços) e os inominados. Nas isenções relativas às transmissões de bens imóveis vamos abordar a isenção nos casos de aquisição de prédios para revenda, assim como analisar a isenção em situações de cessão de posição contratual. Relativamente ao processo de renúncia, vamos expor as condições e os procedimentos (previstos no Decreto-lei nº 21/2007, de 29 de janeiro) necessários para exercer a renúncia à isenção.

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Neste estudo apresenta-se uma avaliação do impacto da Biblioteca da Faculdade de Ciências da Universidade do Porto (FCUP), na perspetiva dos estudantes e observando alguns dados relativos ao uso da Biblioteca FCUP. A investigação recorre a uma análise de métodos mistos, isto é, avalia dados qualitativos, que descrevem mas não mensuram as características, em especial as ações humanas, e dados quantitativos que apresentam forma numérica e revelam uma quantidade certa podendo ser sujeitos a manipulação estatística. A «Notícias da Biblioteca», uma newsletter publicada bimestralmente pela Biblioteca FCUP, inclui uma seção denominada “Voz do Utilizador”, onde são incluídos pequenos textos de opinião da autoria dos utilizadores, escolhidos aleatoriamente e, que frequentam as instalações destes serviços da FCUP. Aplicando a Norma Internacional ISO16439:2014 (E) – Information and documentation – Methods and procedures for assessing the impact of libraries, examinaram-se vinte textos de opinião, sobre a biblioteca, redigidos por estudantes de várias nacionalidades, publicados de janeiro de 2013 a dezembro de 2014, na «Notícias da Biblioteca». Investigaram-se ainda 7 entrevistas. Apelando à Estatística Descritiva efetuaram-se tabelas de contingência que são úteis para conhecer a relação entre os dados em função de determinados grupos, isto é, observar a frequência de uma variável em função das categorias de outra variável. Com as tabelas de contingência obtém-se percentagens em função dos efeitos do impacto da biblioteca e dos grupos de estudantes e analisa-se a relação entre eles. O estudo utilizou ainda alguns dados estatísticos indicadores que mostram o impacto, a saber, indicadores de desempenho relativos ao uso da biblioteca – número de visitas per capita e número de empréstimos per capita. Estas avaliações em bibliotecas fornecem informações úteis para as chefias de topo, para o desenvolvimento de novos projetos e a otimização do impacto e desempenho destes serviços das instituições de Ensino Superior./ This study presents an impact assessment of the Library of the Faculty of Science, University of Porto (FCUP), from the students’ point of view and some statistical data collected from the FCUP Library use. We used a mixed methods research, i.e., qualitative data, that describes but does not measure characteristics, in particular human actions, and quantitative data represented by numbers that indicate exact amounts which can be statistically manipulated. The newsletter «Notícias da Biblioteca» published, bimonthly, by the FCUP Library includes a section called “User Voice” where we can find opinion texts expressed by library users, randomly chosen, and who usually go to the library. Applying International Standard ISO16439: 2014 (E) - Information and documentation - Methods and procedures for assessing the impact of libraries, we examined 20 opinion texts written by students of various nationalities, published from January 2013 to December 2014, in «Notícias da Biblioteca» During this period of time, we have taken seven interviews. Using the principles of Descriptive Statistics, we produced Contingency Tables to determine how the data relates in terms of certain groups, i.e., to observe the frequency of the dependent variable on another categorical variable. Working with the Contingency Tables allowed us to obtain percentages according to the effects of the impact of the library in various groups of students and study the relationship between them. This study also used some statistical data that show the impact of the library within the institution, such as: performance indicators relating to the use of the library - number of visits per capita and number of loans per capita. These assessment impact studies in libraries provide useful data for the top management, to develop new projects, thus maximizing the impact and performance of these services of higher education institutions.