Estabilidade aeróbica de silagens de capim-elefante (Pennisetum purpureum, Schum) emurchecido e tratado com inoculante microbiano

Para avaliar o efeito de um inoculante microbiano sobre a estabilidade aeróbica de silagens de capim-elefante (Pennisetum purpureum, Schum) pré-seco, foi conduzido um experimento na UNESP, Campus de Jaboticabal. O capim foi cortado com 96 dias de crescimento, permanecendo sob ação do sol, por aproximadamente 5 horas para o emurchecimento. Foram confeccionados silagens, em barricas plásticas de 200 L de capacidade, que receberam (CI) ou não (SI) o inoculante no momento da ensilagem. Para o estudo da deterioração aeróbica, na abertura dos silos (T0), cada barrica foi subdividida em três profundidades e as silagens expostas ao ar em um sistema, usado para a determinação de CO2, por 2 (T2), 4 (T4), 6 (T6) e 8 (T8) dias. A silagem da camada superficial não apresentou diferenças no valor de pH e contagem de leveduras, em relação à da camada intermediária, porém ambas apresentaram valores superiores à camada mais profunda. O teor de N-NH3 da camada superior foi menor que o da intermediária e profunda, que não diferiram entre si. A interação significativa entre inóculo e tempo de exposição mostrou que nos primeiros tempos de aeração (T0; T2 e T4) as silagens inoculadas não diferiram das controle em termos de pH, teor de N-NH3 e contagem de bolores, mas com avanço do tempo (T6 e T8) passaram a apresentar menor valor de pH, menor contagem de fungos e tendência a menor produção de CO2, indicando menor velocidade de deterioração após seis dias de exposição aeróbica.

Aplicação do método de análise hierárquica na tomada de decisão para adoção de computação em nuvem: um estudo de caso na federação das indústrias do RN

The progresses of the Internet and telecommunications have been changing the concepts of Information Technology IT, especially with regard to outsourcing services, where organizations seek cost-cutting and a better focus on the business. Along with the development of that outsourcing, a new model named Cloud Computing (CC) evolved. It proposes to migrate to the Internet both data processing and information storing. Among the key points of Cloud Computing are included cost-cutting, benefits, risks and the IT paradigms changes. Nonetheless, the adoption of that model brings forth some difficulties to decision-making, by IT managers, mainly with regard to which solutions may go to the cloud, and which service providers are more appropriate to the Organization s reality. The research has as its overall aim to apply the AHP Method (Analytic Hierarchic Process) to decision-making in Cloud Computing. There to, the utilized methodology was the exploratory kind and a study of case applied to a nationwide organization (Federation of Industries of RN). The data collection was performed through two structured questionnaires answered electronically by IT technicians, and the company s Board of Directors. The analysis of the data was carried out in a qualitative and comparative way, and we utilized the software to AHP method called Web-Hipre. The results we obtained found the importance of applying the AHP method in decision-making towards the adoption of Cloud Computing, mainly because on the occasion the research was carried out the studied company already showed interest and necessity in adopting CC, considering the internal problems with infrastructure and availability of information that the company faces nowadays. The organization sought to adopt CC, however, it had doubt regarding the cloud model and which service provider would better meet their real necessities. The application of the AHP, then, worked as a guiding tool to the choice of the best alternative, which points out the Hybrid Cloud as the ideal choice to start off in Cloud Computing. Considering the following aspects: the layer of Infrastructure as a Service IaaS (Processing and Storage) must stay partly on the Public Cloud and partly in the Private Cloud; the layer of Platform as a Service PaaS (Software Developing and Testing) had preference for the Private Cloud, and the layer of Software as a Service - SaaS (Emails/Applications) divided into emails to the Public Cloud and applications to the Private Cloud. The research also identified the important factors to hiring a Cloud Computing provider

Desenvolvimento de antenas de microfita com Patch em anel utilizando materiais ferrimagnéticos e metamateriais

In general, the materials used as substrates in the project of microstrip antennas are: isotropic, anisotropic dielectrics and ferrimagnetic materials (magnetic anisotropy). The use of ferrimagnetic materials as substrates in microstrip patch antennas has been concentrated on the analysis of antennas with circular and rectangular patches. However, a new class of materials, called metamaterials, has been currently the focus of a great deal of interest. These materials exhibit bianisotropic characteristics, with permittivity and permeability tensors. The main objective of this work is to develop a theoretical and numerical analysis for the radiation characteristics of annular ring microstrip antennas, using ferrites and metamaterials as substrates. The full wave analysis is performed in the Hankel transform domain through the application of the Hertz vector potentials. Considering the definition of the Hertz potentials and imposing the boundary conditions, the dyadic Green s function components are obtained relating the surface current density components at the plane of the patch to the electric field tangential components. Then, Galerkin s method is used to obtain a system of matrix equations, whose solution gives the antenna resonant frequency. From this modeling, it is possible to obtain numerical results for the resonant frequency, radiation pattern, return loss, and antenna bandwidth as a function of the annular ring physical parameters, for different configurations and substrates. The theoretical analysis was developed for annular ring microstrip antennas on a double ferrimagnetic/isotropic dielectric substrate or metamaterial/isotropic dielectric substrate. Also, the analysis for annular ring microstrip antennas on a single ferrimagnetic or metamaterial layer and for suspended antennas can be performed as particular cases

Análise e projeto de superfícies seletivas de frequência com elementos pré-fractais para aplicações em comunicações indoor

In this thesis, a frequency selective surface (FSS) consists of a two-dimensional periodic structure mounted on a dielectric substrate, which is capable of selecting signals in one or more frequency bands of interest. In search of better performance, more compact dimensions, low cost manufacturing, among other characteristics, these periodic structures have been continually optimized over time. Due to its spectral characteristics, which are similar to band-stop or band-pass filters, the FSSs have been studied and used in several applications for more than four decades. The design of an FSS with a periodic structure composed by pre-fractal elements facilitates the tuning of these spatial filters and the adjustment of its electromagnetic parameters, enabling a compact design which generally has a stable frequency response and superior performance relative to its euclidean counterpart. The unique properties of geometric fractals have shown to be useful, mainly in the production of antennas and frequency selective surfaces, enabling innovative solutions and commercial applications in microwave range. In recent applications, the FSSs modify the indoor propagation environments (emerging concept called wireless building ). In this context, the use of pre-fractal elements has also shown promising results, allowing a more effective filtering of more than one frequency band with a single-layer structure. This thesis approaches the design of FSSs using pre-fractal elements based on Vicsek, Peano and teragons geometries, which act as band-stop spatial filters. The transmission properties of the periodic surfaces are analyzed to design compact and efficient devices with stable frequency responses, applicable to microwave frequency range and suitable for use in indoor communications. The results are discussed in terms of the electromagnetic effect resulting from the variation of parameters such as: fractal iteration number (or fractal level), scale factor, fractal dimension and periodicity of FSS, according the pre-fractal element applied on the surface. The analysis of the fractal dimension s influence on the resonant properties of a FSS is a new contribution in relation to researches about microwave devices that use fractal geometry. Due to its own characteristics and the geometric shape of the Peano pre-fractal elements, the reconfiguration possibility of these structures is also investigated and discussed. This thesis also approaches, the construction of efficient selective filters with new configurations of teragons pre-fractal patches, proposed to control the WLAN coverage in indoor environments by rejecting the signals in the bands of 2.4~2.5 GHz (IEEE 802.11 b) and 5.0~6.0 GHz (IEEE 802.11a). The FSSs are initially analyzed through simulations performed by commercial software s: Ansoft DesignerTM and HFSSTM. The fractal design methodology is validated by experimental characterization of the built prototypes, using alternatively, different measurement setups, with commercial horn antennas and microstrip monopoles fabricated for low cost measurements

Análise de superfícies seletivas de freqüência através do método dos potenciais vetorias de Hertz

This work presents a theoretical and numerical analysis of Frequency Selective Surfaces (FSS) with elements as rectangular patch, thin dipole and crossed dipole mounted on uniaxial anisotropic dielectric substrate layers for orientations of the optical axis along x, y and z directions. The analysis of these structures is accomplished by combination of the Hertz vector potentials method and the Galerkin's technique, in the Fourier transform-domain, using entire¬domain basis functions. This study consists in the use of one more technique for analysis of FSS on anisotropic dielectric substrate. And presents as the main contribution the introduction of one more project parameter to determinate the transmission and reflection characteristics of periodic structures, from the use of anisotropic dielectric with orientations of the crystal optical axis along x, y and z directions. To validate this analysis, the numerical results of this work are compared to those obtained by other authors, for FSS structures on anisotropic and isotropic dielectric substrates. Also are compared experimental results and the numerical correspondent ones for the FSS isotropic case. The technique proposed in this work is accurate and efficient. ln a second moment, curves are presented for the transmission and reflection characteristics of the FSS structures using conducting patch elements mounted on uniaxial anisotropic dielectric substrate layers with optical axis oriented along x, y and z directions. From analysis of these curves, the performance of the considered FSS structures as function of the optical axis orientation is described

Análise de linhas de fita não-homogêneas com camadas dielétricas anisotrópicas

Abstract

Análise teórica e experimental de superfícies seletivas de freqüência e suas aplicações em antenas planares

This work presents a theoretical and numerical analysis of structures using frequency selective surfaces applied on patch antennas. The FDTD method is used to determine the time domain reflected fields. Applications of frequency selective surfaces and patch antennas cover a wide area of telecommunications, especially mobile communications, filters and WB antennas. scattering parameters are obteained from Fourier Transformer of transmited and reflected fields in time domain. The PML are used as absorbing boundary condition, allowing the determination of the fields with a small interference of reflections from discretized limit space. Rectangular patches are considered on dielectric layer and fed by microstrip line. Frequency selective surfaces with periodic and quasi-periodic structures are analyzed on both sides of antenna. A literature review of the use of frequency selective surfaces in patch antennas are also performed. Numerical results are also compared with measured results for return loss of analyzed structures. It is also presented suggestions of continuity to this work

Utilizando a televisão digital como um meio de comunicação para ambientes interativos reais

This Dissertation aims to provide a communication mechanism between Digital TV viewers and interaction devices, such as robots, for example, placed on the environment from which a TV program is being live broadcasted. Such communication mechanism has the objective to allow viewers controll the Interaction Devices through their TV devices, using the broadcast channel present in Interactive Digital TV systems, and receive data from the devices by the broadcast channel. This system was projected as a middlewaer system where the Interaction Devices in the TV program set are interconnected, creating a Interactive Device Network. With this approach, the system is capable of manage the devices on the network, controlling the flow of coming and leaving elements, in a transparent way for the viewers. The system yet allows the Interaction Devices communicate each other, with a integrated communication channel with no worries about the physical communication layer

Proposta de uma máquina para colheita mecanizada de babaçu (Orbignya phalerata Mart.) para a agricultura familiar

O babaçu é uma planta de importância capital na economia de subsistência do norte do Brasil. Sua configuração sócio-ambiental o torna destaque na situação regional amazônica, onde os produtos advindos do babaçu possibilitam renda para a camada mais pobre da população amazônica, além da questão ambiental que é conotada à preservação dos babaçuais naturais. Um dos gargalos técnicos da produção do babaçu, em especial visando a extração do óleo de babaçu, é a colheita feita de forma manual e no sistema extrativista. O objetivo deste trabalho é propor o conceito de uma colhedora de babaçu moto-mecanizada, capaz de trabalhar em cultivos artificiais, assim como em florestas naturais. Foi utilizada a metodologia de projeto da matriz morfológica, onde foram elencadas as possíveis combinações de mecanismos e elementos para uma colhedora de babaçu. Como resultado foi obtido um conceito teórico, sendo concluída a viabilidade técnica de tal projeto, em estudos futuros pretende-se desenvolver estudos de viabilidade técnica detalhados, assim como estudos de viabilidade econômica.

Fertirrigação com diferentes doses de NPK e seus efeitos sobre a produção e qualidade de frutos de laranja (Citrus sinensis O.) 'Valência'

O experimento foi realizado na Fazenda Três Irmãos, no município de Pratânia, Estado de São Paulo, com o objetivo de estudar o efeito da fertirrigação com diferentes doses de NPK aplicadas por meio de um sistema de irrigação por microaspersão na cultura da laranja em comparação com a adubação convencional irrigada e não irrigada. A avaliação dos efeitos da irrigação e da fertirrigação na cultura foi feita com base na produção e qualidade dos frutos colhidos, na análise de solo da camada de 0-20 cm e na análise de folhas. Os tratamentos não influenciaram significativamente a produtividade de acordo com a análise estatística realizada, embora se tenha observado uma tendência de maior produtividade nos tratamentos de fertirrigação para uma mesma dose. A análise de qualidade dos frutos não mostrou diferenças significativas entre os tratamentos. Os teores de alguns dos elementos obtidos na análise de solo apresentaram diferenças significativas proporcionadas pela irrigação e/ou modo de aplicação dos fertilizantes à cultura. A análise de folhas diferiu quanto aos teores de Ca, Mg e K.

Produção, acúmulo e exportação de nutrientes em grama esmeralda adubada com lodo de esgoto

Objetivou-se com o trabalho avaliar a extração total de macronutrientes pela grama esmeralda em função de doses de lodo de esgoto. O experimento foi instalado em área comercial de produção de grama esmeralda, localizada na cidade de Itapetininga (SP). O delineamento experimental utilizado foi o de blocos ao acaso; em parcelas subdivididas, com quatro repetições, sendo as parcelas principais constituídas de cinco doses de lodo (0, 10, 20, 30 e 40 Mg ha-1, base seca), e as subparcelas com dois sistemas de manejo (com e sem o uso de escarificador utilizado para romper uma camada superficial compactada). As doses de lodo aplicadas correspondem às doses de 100, 200, 300 e 400 kg ha-1 de nitrogênio. O aumento das doses de lodo de esgoto promoveu maior remoção de nutrientes pela grama esmeralda. As doses mais elevadas de N fornecido com o lodo de esgoto promoveram excessivo crescimento da grama e a redução do sistema radicular. Doses intermediárias entre 20 e 30 Mg ha-1 foram mais interessantes, pois reduziram a quantidade de aparas acumuladas, e promoveram um bom desenvolvimento dos rizomas + estolões e raízes, permitindo a formação de tapetes com maior resistência.

Implementação de processador banda base ofdma para downlink lte em fpga

This work treats of an implementation OFDMA baseband processor in hardware for LTE Downlink. The LTE or Long Term Evolution consist the last stage of development of the technology called 3G (Mobile System Third Generation) which offers an increasing in data rate and more efficiency and flexibility in transmission with application of advanced antennas and multiple carriers techniques. This technology applies in your physical layer the OFDMA technical (Orthogonal Frequency Division Multiple Access) for generation of signals and mapping of physical resources in downlink and has as base theoretical to OFDM multiple carriers technique (Orthogonal Frequency Division Multiplexing). With recent completion of LTE specifications, different hardware solutions have been developed, mainly, to the level symbol processing where the implementation of OFDMA processor in base band is commonly considered, because it is also considered a basic architecture of others important applications. For implementation of processor, the reconfigurable hardware offered by devices as FPGA are considered which shares not only to meet the high requirements of flexibility and adaptability of LTE as well as offers possibility of an implementation quick and efficient. The implementation of processor in reconfigurable hardware meets the specifications of LTE physical layer as well as have the flexibility necessary for to meet others standards and application which use OFDMA processor as basic architecture for your systems. The results obtained through of simulation and verification functional system approval the functionality and flexibility of processor implemented

Efeito da inclinação do plano de terra para antenas de microfita multicamadas com elementos parasitas fractais

This work presents the analysis of an antenna of fractal microstrip of Koch with dielectric multilayers and inclinations in the ground plane, whose values of the angles are zero degree (without inclinations), three, seven and twelve degrees. This antenna consists of three dielectric layers arranged vertically on each other, using feeding microstrip line in patch 1, of the first layer, which will feed the remaining patches of the upper layers by electromagnetic coupling. The objective of this work is to analyze the effects caused by increase of the angle of inclination of the ground plane in some antenna parameters such as return loss, resonant frequency, bandwidth and radiation pattern. The presented results demonstrate that with the increase of the inclination angle it is possible to get antennas with characteristics multiband, with bigger bandwidth, and improving the impedance matching for each case analyzed, especially the larger angle

Resistência do solo à penetração, cobertura vegetal e produtividade do milho em plantio direto escarificado

O objetivo deste trabalho foi avaliar a influência da operação da escarificação ao longo do tempo sobre a estrutura de um solo em plantio direto, assim como os seus efeitos sobre a produtividade do milho e a formação de cobertura vegetal. O trabalho foi conduzido em um NITOSSOLO VERMELHO no município de Botucatu, São Paulo, Brasil. O delineamento experimental foi o de blocos casualizados em esquema de parcelas subdivididas, sendo as parcelas o fator manejo do solo (em plantio direto e em escarificação) e as subparcelas o fator período de avaliação (quatro e 18 meses após a escarificação) com quatro repetições por tratamento. Os resultados indicaram que, após o período de quatro meses, a escarificação reduziu significativamente a resistência do solo à penetração, até a profundidade de atuação das hastes do escarificador (0,30 m), e, após o período de 18 meses, o efeito da escarificação sobre a resistência do solo à penetração ocorreu apenas na camada superficial do solo (0,05 e 0,10 m). em área cultivada em sistema plantio direto, o efeito do preparo do solo com escarificador sobre a resistência à penetração tende a desaparecer no período de 1,5 anos. A quantidade de matéria seca na superfície do solo, em plantio direto, foi 30% superior ao solo com antecedente de escarificação pelo período de quatro meses.

Estudo do efeito de substratos metamateriais em parâmetros de antenas de microfita

Microstrip antennas are subject matter in several research fields due to its numerous advantages. The discovery, at 1999, of a new class of materials called metamaterials - usually composed of metallic elements immersed in a dielectric medium, have attracted the attention of the scientific community, due to its electromagnetic properties, especially the ability to use in planar structures, such as microstrip, without interfering with their traditional geometry. The aim of this paper is to analyze the effects of one and bidimensional metamaterial substrates in microstrip antennas, with different configurations of resonance rings, SRR, in the dielectric layer. Fractal geometry is applied to these rings, in seeking to verify a multiband behavior and to reduce the resonance frequency of the antennas. The results are then given by commercial software Ansoft HFSS, used for precise analysis of the electromagnetic behavior of antennas by Finite Element Method (FEM). To reach it, this essay will first perform a literature study on fractal geometry and its generative process. This paper also presents an analysis of microstrip antennas, with emphasis on addressing different types of substrates as part of its electric and magnetic anisotropic behavior. It s performed too an approach on metamaterials and their unique properties