Made available in DSpace on 2016-04-25T18:40:34Z (GMT). No. of bitstreams: 1 Dissertacao Marcos Davila.pdf: 726015 bytes, checksum: 98dea650e21db5f9650341ec4c71a493 (MD5) Previous issue date: 2005-05-17 / Pontificia Universidade de São Paulo / The Brazilian firms growth is the challenge to be considered within the microeconomic agenda in order to include the country in the global competition s context. For such growth to happen, it is necessary to overcome external barriers, such as taxation, financing, regulation and technological policies. Besides, internal barriers should also be overcome, such as organizational culture and management. This work discusses the management of such firms regarding its growth phase, from the use of the COSO Committee of Sponsoring Organizations internal control method. The purpose is to assess the applicability of such method over the brazilian small business, meanly at the moment in which the small firm become a medium sized company, considering that at this point a strict and on going oversight became impossible. Such applicability has been evaluated through analysis of writings describing the brazilian small business features in comparison with the COSO internal control method and also through inquiry to small business experts. The conclusions obtained indicates that the COSO internal control method is applicable for the brazilian small business if changes are carried out. Required changes includes a replacement of the focus on disclosure of financial statements to a new focus on management accounting, pointed out as a need by the experts, and also a higher degree of details and examples of practical cases, meanly about the identification of a set of usual risks for small business / O crescimento do porte das empresas brasileiras é o desafio que se impõe na agenda microeconômica para inserir o Brasil no contexto da competição globalizada. Para que este crescimento ocorra, é necessário que barreiras externas à empresa sejam superadas: os aspectos da tributação, o acesso a financiamentos, regulamentação e políticas tecnológicas. Além disso, barreiras internas também precisam ser vencidas, como os aspectos de gerenciamento e de cultura organizacional. Este trabalho aborda a questão do gerenciamento dessas empresas em relação à sua fase de crescimento, a partir da utilização do método de controles internos do COSO Committee of Sponsoring Organizations. Propõe avaliar a aplicabilidade deste método em relação às empresas brasileiras de pequeno porte, principalmente no momento em que a pequena empresa se torna uma empresa de médio porte, momento este em que a supervisão direta e contínua do proprietário sobre as operações se torna impraticável. Tal aplicabilidade é avaliada através de análises de textos que descrevem as características dos pequenos negócios no Brasil em comparação com o método de controles do COSO, e também através de consulta a especialistas sobre pequenos negócios no Brasil. As conclusões obtidas indicam que o método de controles do COSO pode ser aplicado para empresas brasileiras de pequeno porte mediante adaptações. Dentre as adaptações necessárias, deve-se alterar o foco na divulgação externa de demonstrações financeiras pelo foco em uma boa contabilidade gerencial, apontado como uma carência pelos especialistas consultados, além de haver maior detalhamento e exemplificações, principalmente sobre a identificação de um conjunto de riscos que sejam comuns aos pequenos negócios

Made available in DSpace on 2016-04-26T20:19:34Z (GMT). No. of bitstreams: 1 Ellen Cristina Chaves.pdf: 1517008 bytes, checksum: 2ec583e6494211e14cfeee85b6d5b48c (MD5) Previous issue date: 2010-10-26 / The objective of this thesis is to study Brazilian s accessory tax obligations system focusing on its nature, history and formal structure, its positive and negative aspects, while analyzing some specific accessory obligations and related court decisions. The author chose to review this subject mainly due to its current nature and growing importance in Brazilian´s revenue collection system for instance the introduction of taxation by electronic means that improved gross collection figures and enabled superior scrutiny while increasing the burden for taxpayers. The research included books and journal articles on the matter from well-known authors, data collected from the website of the Brazilian Internal Revenue Service, Federal Supreme Court and the Superior Court of Justice as well as a study from PriceWaterhouseCoopers and World Bank Group written in 2010. The result of the thesis illustrates both the theoretical and practical approaches on the subject, in order to analize the positive and negative aspects of the institution of accessory tax obligations / O objetivo deste trabalho é estudar as obrigações tributárias acessórias, sobretudo a natureza, fonte e a estrutura formal do instituto; seus aspectos positivos, negativos e consequentes limites de imposição; bem como analisar algumas obrigações tributárias acessórias em espécie e decisões judiciais sobre o assunto. A escolha do estudo justifica-se em razão da atualidade e importância do tema, pois crescente a imposição de deveres instrumentais no cenário brasileiro, principalmente por meios eletrônicos, o que por um lado facilita a atividade arrecadatória e fiscalizatória da Administração Tributária, mas por outro implica cada vez maiores exigências e ônus para os administrados. A pesquisa do tema baseou-se principalmente em obras doutrinárias e artigos de periódicos; também houve coleta de dados no sítio eletrônico da Receita Federal do Brasil, do Supremo Tribunal Federal e do Superior Tribunal de Justiça, bem como estudos da PriceWaterhouseCoopers e do Banco Mundial em 2010. O resultado do trabalho revela a abordagem tanto de aspectos teóricos quanto práticos sobre o assunto, a fim de analisar os aspectos positivos e negativos da instituição das obrigações tributárias acessórias

O objetivo deste trabalho é avaliar a variação da temperatura e umidade do ar em função: a) das diferentes exposições e declividades de vertentes; b) das diferenças entre a vegetação e o perfil hídrico do solo no espaço tridimensional (vertical e horizontal) da bacia B do núcleo Cunha do Parque Estadual da Serra do Mar, Estado de São Paulo. O estudo foi realizado com base no conceito de ritmo apoiado pelo trabalho de campo buscando relações consistentes entre atributos e controles climáticos. Foi realizado o monitoramento de temperatura e umidade do ar com freqüência de amostragem de 15 minutos durante o inverno de 2008 ao outono de 2009. Os dados registrados foram analisados e relacionados aos controles climáticos de superfície e com os sistemas atmosféricos atuantes para três níveis isobáricos: superfície, 500 hPa e 250 hPa. Dos cruzamentos entre os vários produtos obtiveram-se diversos mapas e diagramas espaço-tempo que representam a estrutura espacial e vertical dos atributos climáticos. Os resultados apontam para a importância do relevo nos ritmos climáticos, relacionados aos processos que são derivados, com as vertentes SW mais frias e úmidas e com ritmos mais lentos em relação às vertentes NE. Os vales apresentam as maiores amplitudes e ritmo mais rápido, enquanto os topos o oposto. Sobre o vale os nevoeiros são freqüentes, bem como a formação de orvalho e geada, enquanto os topos estão normalmente livres desses fenômenos. A comparação dos microclimas revelaram que o dossel mais aberto apresenta ritmos mais variáveis, regulados pela presença-ausência do Sol, enquanto que dentro da floresta o ritmo é mais harmônico, regulado pela biomassa e lentos fluxos de água no solo. Revelou ainda pela análise tridimensional que o perfil vertical dos atributos climáticos é determinado pelas características do dossel, pelo perfil hídrico do solo e da posição topográfica. Sob situações de calor extremo a transpiração das árvores é importante para a manutenção da umidade dentro da floresta, dificultando também a elevação da temperatura nestes ambientes. / The objective of this work was to evaluate air temperature and humidity variations related to: a) different hillslope orientations and gradients; b) differences between vegetation types and soil moisture profile in tridimensional space (vertical and horizontal). The study area was a drainage microbasin called Basin B, located at Núcleo Cunha do Parque Estadual da Serra do Mar, eastern São Paulo state. The study was based on the rhythm concept, supported by field work, in order to find consistent relationship between climatic attributes and controls. It was performed an air temperature and humidity monitoring in a sampling frequency of 15 minutes, from winter of 2008 to fall of 2009. The collected data were analyzed and then associated with climatic surface controls and atmospheric systems at 3 isobaric levels: surface, 500 hPa and 250 hPa. Maps and space-time diagrams, representing the spatial and vertical structure of climatic attributes, were obtained by the crossing analyses of all data. Results pointed out the importance of landforms on the control of climatic rhythms and associated processes. Southwestern hillslopes are colder and more humid, presenting slower rhythms if compared with NE hillslopes. Valleys present higher amplitudes and rhythm speed if compared with tops. Over the valleys, the occurrence of fog, dew and frost are frequent, but these processes arent registered on the tops. Comparison between different microclimates revealed that the opened canopy present more variable rythms, regulated by presence-absence of sunlight. Inside the forest the rhythm are more harmonic, being regulated by biomass and slow subsurface water flows. Also, the tridimensional analysis revealed that the vertical profile of climatic attributes is determined by canopy structure, soil moisture profile and topographical position. Under extreme heat situation, tree transpiration is very important to keep the humidity inside the forest, preventing the elevation of temperatures in these environments.

This thesis aims to investigate the controllability and observability of the discrete fractional linear time-invariant state-space model. First, we will establish key concepts and properties which are the tools necessary for our task. In the third chapter, we will discuss the discrete state-space model and set up the criteria for these two properties. Then, in the fourth chapter, we will attempt to apply these criteria to the discrete fractional model. The general flow of our objectives is as follows: we start with the first-order linear difference equation, move on to the discrete system, then the fractional difference equation, and finally the discrete fractional system. Throughout this process, we will develop the solutions to the (fractional) difference equations, which are the basis of our criteria.

The objective of this whole study was to evaluate a LiDAR sensor for high-resolution remote sensing in agriculture. A linear motion system was developed to precisely control the dynamics of LiDAR sensor in effort to remove uncertainty in the LiDAR position/velocity while under motion. A user control interface was developed to operate the system under different velocity profiles and log LiDAR data synchronous to the motion of the system. The LiDAR was then validated using multiple test targets with five different velocity profiles to determine the effect of sensor velocity and height above a target on measurement error. The results indicated that the velocity of the LiDAR was a significant factor affecting the error and standard deviation of the LiDAR measurements, although only by a small margin. Then the concept of modeling the alfalfa using the linear motion system was introduced. Two plots of alfalfa were scanned and processed to extract height and volume and was compared with photogrammetric and field measurements. Insufficient alfalfa plots were scanned which prevented any statistical analysis from being used to compare the different methods. However, the comparison between LiDAR and photogrammetric data showed some promising results which may be further replicated in the future.

Satellite power systems can be understood as islanded dc microgrids supplied by specialized and coordinated solar cell arrays augmented by electrochemical battery systems to handle high-power loads and periods of eclipse. The periodic availability of power, the limited capacity of batteries, and the dependence of all mission service on power consumption create a unique situation in which temporal power and energy scarcity exist. A multi-period model of an orbital satellite power system’s performance over a mission’s duration can be constructed. A modular power system architecture is used to characterize the system’s constraints. Using mathematical programming, an optimization problem can be posed such that the optimal power and energy ratings for the power system are determined for any load schedule imposed by a given mission’s requirements. The optimal energy trajectory of the electrical power system over a mission’s duration is also determined when the mathematical programming problem is solved. A generic set of mission requirements is identified to test this approach, but the objective function of the resulting optimization problem can be modified to return different results. These results can provide a clear illustration of the trade-offs that designers of such power systems consider in the design process.

The helicopter possesses the unrivaled capacity for vertical takeoff and landing which has made the helicopter suitable for numerous tasks such as carrying passengers and equipment, providing air medical services, firefighting, and other military and civil tasks. The nature of the aerodynamic environment surrounding the helicopter gives rise to a significant amount of vibration to its whole body. Among different sources of vibrations, the main rotor blade is the major contributor. The dynamic characteristics of the hingeless rotor consisting of elastic blades are of particular interest because of the strongly coupled equations of motion. The elastic rotor blades are subjected to coupled flapping, lead-lag, and torsional (triply coupled) deflections. Once these deflections exceed the maximum allowable level, the structural integrity of the rotor blade is affected leading to the ultimate failure. The maximum deflection that a blade can undergo for a specific operating condition needs to be estimated. Therefore, in this study, the triply coupled free and forced response of the Bo 105 hingeless, composite helicopter rotor blade is investigated at hovering and forward flights. At first, a model of the composite cross-section of the rotor blade is proposed for which a semi-analytical procedure is developed to estimate the sectional properties. These properties are used in the mathematical model of the free vibration of the rotor blade having the proposed cross-section to solve for the natural frequencies and the mode shapes. The aerodynamic loadings from the strip theory are used to estimate the time-varying forced response of the rotor blade for hovering and forward flights. The large flapping and inflow angles are introduced in the mathematical model of the forward flight and the corresponding nonlinear mathematical model requires a numerical solution technique. Therefore, a generalization of the method of lines is performed to develop a robust numerical solution in terms of time-varying deflections and velocities. The effect of the unsteady aerodynamics at the forward flight is included in the mathematical model to estimate the corresponding dynamic response. Both the analytical and the numerical models are validated by finite element results and the convergence study for the free vibration is performed.

This thesis presents a new modular structure of the axial flux Switched Reluctance Motor (SRM). The design consists of four stator disks with each adjacent disk rotated 30 degrees apart and four rotor disks connected to a common shaft. The proposed design aims to reduce the unwanted radial force, mitigate the torque ripple, and improve the efficiency. The modular structure distributes the radial force and torque strokes along the axial length of the motor, potentially damping the torque pulsation. In addition, the modular structure would deliver the rating power at a lower current level, reducing the overall ohmic loss. Moreover, if a fault occurs on a motor disk or its control unit, the motor would still operate through other disks, increasing the reliability of the system. To verify the effectiveness of the proposed design, the magneto-static and transient performance of the motor are compared with the conventional single layer structure using 3-D Finite-Element (FE) software tool to see that the proposed motor performs better with lower torque ripple and lower radial force than a conventional single layer structure.

The balancing of a wind turbine rotor is a crucial step affecting the machine’s performance, reliability, and safety, as it directly impacts the dynamic loads on the entire structure. A rotor can be balanced either statically or dynamically. A method of rotor balancing was developed that achieves both the simplicity of static balancing and the accuracy of dynamic balancing. This method is best suited, but not limited, to hollow composite blades of any size. The method starts by quantifying the mass and center of gravity of each blade. A dynamic calculation is performed to determine the theoretical shaking force on the rotor shaft at the design operating speed. This force is converted to a net counterbalance mass required for each blade. Despite the most careful methodology, there may still be large errors associated with these measurements and calculations. Therefore, this new method includes a physical verification of each blade’s individual balance against all other blades on the rotor, with the ability to quantify the discrepancy between blades, and make all balance adjustments in situ. The balance weights are aluminum plugs of varying lengths inserted into the root of each blade with a threaded steel rod running through the middle. The balance adjustment is thus not visible from outside. The weight of the plug and rod represent the coarse counterbalance of each blade, based on the dynamic calculations. The threaded steel rod acts as a fine adjustment on the blades’ mass moment when traveled along the plug. A dedicated blade-balance apparatus, designed and constructed in-house, is used to verify and fine-tune each individual blade and compare it to all other blades on the rotor. The resulting blade assembly is verified on a full rotor static balancing apparatus. The full rotor apparatus measures the steady state tilt of the rotor when balanced on a point. Next, the rotors' tilt is related to its overall level of imbalance with quantifiable error. Most error comes from the fact that the hub, comparable in mass to the blades, creates a false righting moment of the assembly not present in operation. The fully assembled rotor is tested, pre and post balance, in operation on the turbine at a series of predetermined speeds. This is accomplished with a 3-axis accelerometer mounted on the main turbine shaft bearing and a control system which regulates and records turbine speed at 100 Hz

The new Field Programmable Gate Array (FPGA) technologies and their structures have opened up new approaches to logic design and synthesis. The main feature of an FPGA is an array of logic blocks surrounded by a programmable interconnection structure. Cellular FPGAs are a special class of FPGAs which are distinguished by their fine granularity and their emphasis on local cell interconnects. While these characteristics call for specialized synthesis tools, the availability of logic gates other than Boolean AND, OR and NOT in these architectures opens up new possibilities for synthesis. Among the possible realizations of Boolean functions, XOR logic is shown to be more compact than AND/OR and also highly testable. In this dissertation, the concept of structural regularity and the advantages of XOR logic are used to investigate various synthesis approaches to cellular FPGAs, which up to now have been mostly nonexistent. Universal XOR Canonical Forms, Two-level AND/XOR, restricted factorization, as well as various Directed Acyclic Graph structures are among the proposed approaches. In addition, a new comprehensive methodology for the investigation of all possible XOR canonical forms is introduced. Additionally, a new compact class of XOR-based Decision Diagrams for the representation of Boolean functions, called Kronecker Functional Decision Diagrams (KFDD), is presented. It is shown that for the standard, hard, benchmark examples, KFDDs are on average 35% more compact than Binary Decision Diagrams, with some reductions of up to 75% being observed.