971 resultados para AUDITORES EXTERNOS


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O grafeno é a primeira estrutura bidimensional que se obteve experimentalmente. Sua rede cristalina é uma rede hexagonal, conhecida como "Favo de Mel", possui apenas um átomo de espessura. Cortes em folhas de grafeno, privilegiando determinada direção, geram as chamadas nanofitas de grafeno. Embora o grafeno se comporte como um metal, é sabido que as nanofitas podem apresentar comportamentos semicondutor, metálico ou semimetálico, dependendo da direção de corte e/ou largura da fita. No caso de nanofitas semicondutoras, a largura da banda proibida (band gap), entre outros fatores, depende da largura da nanofita. Neste trabalho adotou-se métodos de primeiros princípios como o DFT (Density Functional Theory), afim de se obter as características tais como curvas de dispersão para nanofitas. Neste trabalho, primeiramente, são apresentados diagramas de bandas de energia e curvas de densidade de estados para nanofitas de grafeno semicondutoras, de diferentes larguras, e na ausência de influências externas. Utilizou-se métodos de primeiros princípios para a obtenção destas curvas e o método das funções de Green do Não Equilíbrio para o transporte eletrônico. Posteriormente foi investigado a influência da hidrogenização, temperatura e tensão mecânica sobre sistema, isso além, de se estudar o comportamento de transporte eletrônico com e sem influência destes fatores externos. Vale ressaltar que as nanofitas de grafeno apresentam possibilidades reais de aplicação em nanodispositivos eletrônicos, a exemplo de nanodiodos e nanotransistores. Por esse motivo, é importante se ter o entendimento de como os fatores externos alteram as propriedades de tal material, pois assim, espera-se que as propriedades de dispositivos eletrônicos também sejam influenciadas da mesma maneira que as nanofitas.

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Pós-graduação em Ciência e Tecnologia de Materiais - FC

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O presente estudo teve com objetivo analisar alguns fatores externos que podem interferir durante uma partida de basquetebol e tentar desvendar quais destes são encarados pelos jogadores como os que têm a maior influência durante o jogo. Buscamos através de um questionário, onde haviam oito questões, estudar a influência da torcida, dos pais, e do técnico com relação ao desempenho de jogadores de basquete da cidade de Rio Claro - SP. Foram entrevistados treze jovens do sexo masculino praticantes de basquetebol na cidade de Rio Claro - SP, na faixa etária de 15 a 17 anos, com tempo de pratica variando de um a quatro anos e treinando cinco vezes por semana. Os principais resultados obtidos foram: A maioria dos entrevistados respondeu que sofre uma influência negativa da torcida adversária; 46,15% dos entrevistados não sofrem nenhum tipo de influência devido à presença dos pais na torcida; A conduta do técnico durante os treinos e os jogos pode influenciar no resultado do jogo; 84,62% responderam que os árbitros podem ter seu desempenho diminuído com a pressão da torcida; A maioria dos entrevistados (69,24%) acha que o técnico, por estar junto da equipe durante os treinos e os jogos, tem uma influência maior no desempenho dos atletas.

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The concern of the society with regard to the pollution if becomes each bigger and necessary time. This pollution generates damage for who is in contact, as much in economic terms how much in quality of life. The particulate matter is one of the main polluting the air, being the most harmful to human health, fine particles and ultra fine (below 2.5 μm in diameter). With this, this work had as objective to mensurar the pollution of air for material particulado through samplings in an urban center, in a siderurgical industry, a conventional coal bunker and a forest fire. The equipment used for the sampling of particles had been the DataRam4 (model DR 4000) and the Impactador de Andersen, both developed by company THERMO SCIENTIFIC. The first equipment uses a system of nefelometry and the second uses a gravimetrical system of sampling. During the carried through samplings, it can be observed in some cases the difficulty in the breath, badly be and low visibility that this type of pollutant can cause. In most cases the results were disturbing. In industry, conventional coal bunker and in the forest were measured values high concentration for particles smaller diameters. Peak concentrations issued were: 40,000 μg/m³, 182,000 μg/m³ and 400,000 μg/m³ for the industry, conventional coal bunker and forest, respectively. Already in the urban centre were satisfactory results, always staying within the limit allowed by the rules in force so far in the country

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The aim of this work is to analyze the stability of the rotational motion’s artificial satellite using the Routh Hurwitz Algorithm (CRH) and the quaternions to describe the satellite’s attitude. This algorithm allows the investigation of the stability of the motion using the coefficients of the characteristic equation associated with the equation of the rotational motion in the linear form. The equations of the rotational motion are given by the four cinematic equations for the quaternion and the three equations of Euler for the spin velocity’s components. In the Euler equations are included the components of the gravity gradient torque (TGG) and the solar radiation torque (TRS). The TGG is generated by the difference of the Earth gravity force direction and intensity actuating on each satellite mass element and it depends on the mass distribution and the form of the satellite. The TRS is created by changing of the linear momentum, which happens due to the interactions of solar photons with the satellite surface. The equilibrium points are gotten by the equation of rotational motion and the CRH is applied in the linear form of these equations. Simulations are developed for small and medium satellites, but the gotten equilibrium points are not stable by CRH. However, when some of the eigenvalues of the characteristic equation are analyzed, it is found some equilibrium points which can be pointed out as stables for an interval of the time, due to small magnitude of the real part of these eigenvalue

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Our twenty-first century society and the rhythm of life and work we have to face in our daily routine compel us to spend most of our lifetime in closed environments, in our houses, educational institutions, hospitals, airports, amongst as many others. The study of the air quality in internal environments (IAQ) is very important for monitoring people’s health effects and their environmental comfort in these locations. One essential parameter to analyze this measure is to evaluate the concentration of dispersed particulates in the air, specially focusing on those thinner particles (below the diameter of 2,5 μm), they can pose serious risks for human being because they can remain in the lungs, penetrate through the pores of our skin, amongst other harmful effects on human’s health. In this work the air quality inside the public library Profª Josina Vasques Ferrari and at Unesp public state library was evaluated, both located in Itapeva, as well as a third one, inside the Communitarian Library of the Federal University in Carlos (UFSCar) from march to may in 2012. In those environments it was analyzed if the concentration of particulates pose any real treat to the users. The equipment used for particle sampling in real time was DataRam 4 (Model DR 4000). The results given for those concentrations of particulates in both internal and external environments revealed figures within the safe standard established by the WHO (World Health Organization), from 25 to μg/m³, the only exception occurred on the fifth floor of the UFSCar library, where the average for concentration stayed at 25,30 of μg/m³

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The objective of the present work was to study the control of the dynamics of diatomic heteronuclear molecules interacting with electric fields created by lasers. Specifically in this work, the molecular photoassociation phenomenon will be analyzed. At this phenomenon, the atom's relative movement is described by a particle that moves in a morse potential well under the influence of an external time dependant force related to the external field. Based on the optimum control theory (OCT), it is presented at the present work laser pulses that alternate a given initial molecular state to a desirable end state, wich in this work was represented by the minimization of a cost functional that indicates how close. To do so, a computational sistem know as Genetic Algorithm (GA) was developed that can be characterizes as an extremelly eficient technique capable of scanning the solutions space and find results close to the optimum solutions

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Internationalization of the Colombian Conflict by the Involvement of External Actors: Action by the OAS in Demobilizing Paramilitary Groups in Colombia This paper discusses the effects of the internationalization of the Colombian armed conflict, understood as the participation of foreign actors in programs regarding the resolution of the conflict. Through an analysis of the involvement of multilateral and state actors, the authors argue that this process involved the dilemma between unilateralism and multilateralism. The empirical analysis is centered on the intervention of conflict mediation mechanisms from the Organization of American States (OAS), specifically the Mission to Support the Peace Process (MAPP/OAS), whose scope is aimed at demobilizing paramilitary groups in Colombia.

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This paper discusses the effects of the internationalization of the Colombian armed conflict, understood as the participation of foreign actors in programs regarding the resolution of the conflict. Through an analysis of the involvement of multilateral and state actors, the authors argue that this process involved the dilemma between unilateralism and multilateralism. The empirical analysis is centered on the intervention of conflict mediation mechanisms from the Organization of American States (OAS), specifically the Mission to Support the Peace Process (MAPP/OAS), whose scope is aimed at demobilizing paramilitary groups in Colombia.

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