93 resultados para Planejamento experimentos
Resumo:
Brazilian law provides a series of rules and policies which regulate space use and occupancy as well as guide environmental planning. Among those are the Permanent Preservation Areas (PPAs) which purpose is to ensure the preservation of elements that are essential to maintain the environmental function and landscape. Another important instrument identifier of spaces are geoenvironmental units, which are synthesis elements grouping areas of similar characteristics and can be used for the analysis of risk, fragility and potential use of spaces. The geoenvironmental units are defined by more complex processes (information integration), focusing not only on individual elements, but being determined from a systemic analysis. Is It possible to identify and delineate APPs from the identification and determination of geoenvironmental units? The aim of this study was to evaluate the potential of geoenvironmental units in the process of identification and delineation of APPs a see how much of the study area, the area by the Coast line in Natal/RN, is still good for occupation. It was used the physiognomic method, in which the limits of the units are plotted on a synthetic document (aerial photographs), valuing aspects of relief in a range of detail by the analysis of systemic categories (element, structure, function and interaction), observed. The methodology used allowed the identification and delineation of eleven geoenvironmental units and, from these, it was possible to identify and delineate four out of the five PPAs occurring in the study area. Only a small space of 1.2 ha of the study area is not considered APP by law. Thus, the occupation of the unoccupied area by the Coast line is not feasible from a legal standpoint. The geoenvironmental units as well as the identified and delineated APPs in the area by the Coast line are spaces which preservation is guaranteed by law in various scopes and are necessary to maintain the environmental functions of the area. The planning for the use and occupation of the area should involve the recovery of degraded areas and the creation of elements that make possible the use as well as attract the community, as provided in the initial planning, by ensuring the public utility and social interest in the Project.
Resumo:
This work describes the synthesis and aplication of homogeneous and heterogenized iron catalysts in the alkylation reaction of toluene with propene, empolying experimental design. The homogenous complex was obtained trough the synthesis of the organic ligand folowed by the complexation of the iron(II) chloride. As to the heterogenized complexes, first were synthetized the inorganic supports (SBA-15, MCM-41 and Al-MCM-41). Then, it was synthetized the ligand again, that through funcionalization with chloropropyltrimethoxysilane (CPTMS), was anchored on the support previously calcinated. To these anchored ligands, was complexed the iron(II) chloride, previously solubilizated in tetrahydrofuran (THF). The organic ligand characterization was accomplished trough nuclear magnetic resonance (NMR) and Infrared spectroscopy (IV). The supports were characterized with x-ray diffraction (DRX), texture analysis with nitrogen adsorption/desorption (before and after the anchoring), termogravimetric analysis (TG) and infrared (IV). The metalic content was quantified trough the atomic absorption spectrophotometry (AAS). The complexes were tested in catalytic reactions emolying ethylaluminium sesquichloride (EASC) as co-catalyst in steel reactor, under mecanic stirring. The reaction conditions ranged from 4 to 36 ◦C, with many aluminum/iron ratios. The catalysts were actives in homogeneous and heterogenized ways. The homogenous catalytic complex showed a maximum turnover frequency (TOF) of 8.63 ×103 · h −1 , while, in some conditions, the anchored complexes showed better results, with TOF of until 8.08 ×103 · h −1 . Aditionally, it was possible to determine an equation, to the homogenous catalyst, that describes the product quantity in function of reacional temperature and aluminum/iron ratio.
Resumo:
This research aims to analyze the housing conditions and socioeconomic of beneficiaries of the Bolsa Família Program – PBF of the North side of Natal city. For that, it is necessary a survey of this region's origins and how its expansion has occurred in the context of local urban development, considering demographic evolution, in particular, from the construction of housing complex and formal and informal allotments. From the field research, consisting of a pilot in loco with some households, it became possible to start the analysis of housing conditions that culminated with a detailed study of the Single Register form of the federal Government (CadÚnico), in relation to 100% (one hundred percent) of the beneficiaries of the Bolsa Familia program (PBF) of Natal city, with qualitative and quantitative information. From this general survey, a cut was done, contemplating only beneficiaries residing in the north of the city. To better understand this reality, the survey found the Brazilian housing deficit, considering its origins, historical contexts and concepts used by the following institutions: João Pinheiro Foundation (FJP), Brazilian Institute of Geography and Statistics (IBGE), Applied Economics Research Institute (IPEA), and Local Plan Housing of Social Interested (PLHIS) and the United Nations Centre for Human Settlements (UN-HABITAT). Furthermore, were compared the various concepts of city and its respective evolution, considering the importance of planning as an instrument of public policy necessary to governmental actions and permanent policy of State. As a result, there are a detach about the deficit and housing conditions in the city of Natal, mainly North Zone, pointing out the importance of using the Unified Register of the federal government as an effective tool to measure the living conditions of Brazilian municipalities.
Resumo:
The fluorescent proteins are an essential tool in many fields of biology, since they allow us to watch the development of structures and dynamic processes of cells in living tissue, with the aid of fluorescence microscopy. Optogenectics is another technique that is currently widely used in Neuroscience. In general, this technique allows to activate/deactivate neurons with the radiation of certain wavelengths on the cells that have ion channels sensitive to light, at the same time that can be used with fluorescent proteins. This dissertation has two main objectives. Initially, we study the interaction of light radiation and mice brain tissue to be applied in optogenetic experiments. In this step, we model absorption and scattering effects using mice brain tissue characteristics and Kubelka-Munk theory, for specific wavelengths, as a function of light penetration depth (distance) within the tissue. Furthermore, we model temperature variations using the finite element method to solve Pennes’ bioheat equation, with the aid of COMSOL Multiphysics Modeling Software 4.4, where we simulate protocols of light stimulation tipically used in optogenetics. Subsequently, we develop some computational algorithms to reduce the exposure of neuron cells to the light radiation necessary for the visualization of their emitted fluorescence. At this stage, we describe the image processing techniques developed to be used in fluorescence microscopy to reduce the exposure of the brain samples to continuous light, which is responsible for fluorochrome excitation. The developed techniques are able to track, in real time, a region of interest (ROI) and replace the fluorescence emitted by the cells by a virtual mask, as a result of the overlay of the tracked ROI and the fluorescence information previously stored, preserving cell location, independently of the time exposure to fluorescent light. In summary, this dissertation intends to investigate and describe the effects of light radiation in brain tissue, within the context of Optogenetics, in addition to providing a computational tool to be used in fluorescence microscopy experiments to reduce image bleaching and photodamage due to the intense exposure of fluorescent cells to light radiation.
Resumo:
Atualmente com o crescente aumento de dispositivos robóticos destinados para aplicação na área de mobilidade de pessoas que sofreram algum tipo de lesão medular, se faz necessário desenvolver novas ferramentas para tornar tais equipamentos mais adaptáveis, seguros e autônomos. Para que as órteses robóticas que auxiliam na locomoção de pessoas paraplégicas possam desempenhar sua função, estas devem ser capazes de reproduzir os movimentos perdidos com o máximo de fidelidade e segurança em ambientes que eventualmente possam conter obstáculos de diferentes tipos como buracos, escadas e calçadas. As órteses robóticas para membros inferiores têm a capacidade de caminhar, subir e descer degraus, todavia, esses movimentos, na maioria das vezes, não se adaptam ao ambiente, sendo assim, para uma órtese robótica que foi projetada para subir um degrau com uma determinada altura ao se deparar com um degrau maior provavelmente não conseguirá realizar essa tarefa com a mesma segurança. Para solucionar esse e outros problemas, esse trabalho apresenta um Sistema de Auxílio à Locomoção (SAL) dotado de um planejador de passos e um gerador de referências angulares com características antropomórficas para a órtese robótica Ortholeg. O SAL utiliza dados antropométricos do usuário para gerar um padrão de marcha personalizado, dessa forma, a órtese em questão é capaz de adaptar o tamanho do passo para não colidir com obstáculos presentes no ambiente e transpor buracos com diversos tamanhos, subir e descer escadas e calçadas com diferentes valores de altura e comprimento. Para desenvolver o sistema de auxílio à locomoção foram adaptadas técnicas de planejamento de caminho, usadas a princípio em robôs bípedes. São apresentados vários experimentos que mostram a órtese Ortholeg realizando alguns movimentos com características antropomórficas para diferentes distâncias de caminhada e três tipos de obstáculos: degrau, buraco e calçada. A autonomia adquirida com a utilização do sistema de planejamento apresentado facilita a utilização de órteses robóticas como também garante uma maior segurança ao usuário.
Resumo:
Ferroelectric ceramics with perovskite structure (ABO3) are widely used in solid state memories (FeRAM’s and DRAM's) as well as multilayered capacitors, especially as a thin films. When doped with zirconium ions, BaTiO3-based materials form a solid solution known as barium zirconate titanate (BaTi1-xZrxO3). Also called BZT, this material can undergo significant changes in their electrical properties for a small variation of zirconium content in the crystal lattice. The present work is the study of the effects of deposition parameters of BaTi0,75Zr0,25O3 thin films by spin-coating method on their morphology and physical properties, through an experimental design of the Box-Behnken type. The resin used in the process has been synthesized by the polymeric precursor method (Pechini) and subsequently split into three portions each of which has its viscosity adjusted to 10, 20 and 30 mPa∙s by means of a rotary viscometer. The resins were then deposited on Pt/Ti/SiO2/Si substrates by spin-coating method on 15 different combinations of viscosity, spin speed (3000, 5500 and 8000 rpm) and the number of deposited layers (5, 8 and 11 layers) and then calcined at 800 ° C for 1 h. The phase composition of the films was analyzed by X-ray diffraction (XRD) and indexed with the JCPDS 36-0019. Surface morphology and grain size were observed by atomic force microscopy (AFM) indicating uniform films and average grain size around 40 nm. Images of the cross section of the films were obtained by scanning electron microscopy field emission (SEM-FEG), indicating very uniform thicknesses ranging from 140-700 nm between samples. Capacitance measurements were performed at room temperature using an impedance analyzer. The films presented dielectric constant values of 55-305 at 100kHz and low dielectric loss. The design indicated no significant interaction effects between the deposition parameters on the thickness of the films. The response surface methodology enabled better observes the simultaneous effect of variables.
Resumo:
Objective: To evaluate the planning and quality of plaster models for fabricati on of removable parti al dentures received from three commercial prosthodonti c laboratories located in the city of João Pessoa, PB, Brazil, which perform the casting procedures in their facilities. Methods: Forty 40 plaster models were photographed per laboratory, totalizing 120 models. The evaluation was performed using two questi onnaires, one designed for the dental prosthesis technicians, and another applied by the investigator for the visual evaluati on of the models. Data were analyzed using the SPSS soft ware version 13.0. Results: Ninety-two (76.7%) models did not present planning. In addition, no model presented references of insertion plane or guide pins. Calculati on of the mouth preparati on index (MPI) to evaluate the distribution of the oclusal and cingulum abutments or rests showed that 86 (71.7%) models were classifi ed as poor, 23 (19.2%) models as good and only 11 (9,.2%) models as acceptable. Defects were found in 102 (85%) models. Conclusion: The prosthodontists are not preparing the mouth of their pati ents, neglecti ng the planning of removable partial dentures, and passing this responsibility to the dental prosthesis technicians. In addition, the quality of the models sent to the laboratories was unsatisfactory.
Resumo:
Objective: To evaluate the planning and quality of plaster models for fabricati on of removable parti al dentures received from three commercial prosthodonti c laboratories located in the city of João Pessoa, PB, Brazil, which perform the casting procedures in their facilities. Methods: Forty 40 plaster models were photographed per laboratory, totalizing 120 models. The evaluation was performed using two questi onnaires, one designed for the dental prosthesis technicians, and another applied by the investigator for the visual evaluati on of the models. Data were analyzed using the SPSS soft ware version 13.0. Results: Ninety-two (76.7%) models did not present planning. In addition, no model presented references of insertion plane or guide pins. Calculati on of the mouth preparati on index (MPI) to evaluate the distribution of the oclusal and cingulum abutments or rests showed that 86 (71.7%) models were classifi ed as poor, 23 (19.2%) models as good and only 11 (9,.2%) models as acceptable. Defects were found in 102 (85%) models. Conclusion: The prosthodontists are not preparing the mouth of their pati ents, neglecti ng the planning of removable partial dentures, and passing this responsibility to the dental prosthesis technicians. In addition, the quality of the models sent to the laboratories was unsatisfactory.
Resumo:
Vegetable oils are characterized as important raw materials in the supplying of natural substances of interest pharmaceutical, food and cosmetic industry. Sunflower oil stands out for its important composition present in unsaturated fatty acids such as oleic acid (C18:1) and linoleic (C18:2), responsible for many health benefits. The main objective of this study is obtain enriched fractions in unsaturated compounds from refined sunflower oil. The oil used in this study was characterized by the determination of some properties, like iodine number, acid number and viscosity. A transesterification was done to transform the triglycerides into their corresponding methyl esters of fatty acids. These was submitted the molecular distillation process, for present as an efficient alternative to separation and purification of these substances, using high vacuum and low temperatures. Of the esters fractions that was obtained, were analyzed by gas chromatography. The experimental design technique was used to evaluate the influence of the temperature variation of evaporation and condensation system on the percentage obtained residue. The evaporator temperature proved to be the most influential variable on the studied response. The optimized conditions for the answer was studied at 100 °C for evaporator temperature and 10 °C for the condenser temperature. The graph of "split ratio" showed that for the lowest flow feed (1 mL/min) and higher evaporator temperature (110 °C) was obtained in the largest fraction of distillate. It also used the study of the influence of evaporator temperature on the concentration of unsaturated compounds. The best operating conditions for temperature was 90 °C reached 82.21 % of unsaturated compounds. Elimination curves of the unsaturated compounds present in the distillate stream were obtained. The simulation results of the molecular distillation process of sunflower oil showed the concentration profiles for three different feed flow rates. The speed, temperature and thickness profiles of the liquid film were obtained. The speed of the film increases as the fluid flows through the walls of the evaporator, reaching a maximum on length of 0.075 m. The film thickness decreases on the route, since many compounds are volatilized. The result of the temperature profile had to be consistent with the literature reproduced, being constant after reaching the maximum operating temperature in the length of 0.15 m. This study allowed characterizing and focusing, through experimental analysis, unsaturated compounds and observing the sunflower oil´s behavior through process simulation.
Resumo:
Vegetable oils are characterized as important raw materials in the supplying of natural substances of interest pharmaceutical, food and cosmetic industry. Sunflower oil stands out for its important composition present in unsaturated fatty acids such as oleic acid (C18:1) and linoleic (C18:2), responsible for many health benefits. The main objective of this study is obtain enriched fractions in unsaturated compounds from refined sunflower oil. The oil used in this study was characterized by the determination of some properties, like iodine number, acid number and viscosity. A transesterification was done to transform the triglycerides into their corresponding methyl esters of fatty acids. These was submitted the molecular distillation process, for present as an efficient alternative to separation and purification of these substances, using high vacuum and low temperatures. Of the esters fractions that was obtained, were analyzed by gas chromatography. The experimental design technique was used to evaluate the influence of the temperature variation of evaporation and condensation system on the percentage obtained residue. The evaporator temperature proved to be the most influential variable on the studied response. The optimized conditions for the answer was studied at 100 °C for evaporator temperature and 10 °C for the condenser temperature. The graph of "split ratio" showed that for the lowest flow feed (1 mL/min) and higher evaporator temperature (110 °C) was obtained in the largest fraction of distillate. It also used the study of the influence of evaporator temperature on the concentration of unsaturated compounds. The best operating conditions for temperature was 90 °C reached 82.21 % of unsaturated compounds. Elimination curves of the unsaturated compounds present in the distillate stream were obtained. The simulation results of the molecular distillation process of sunflower oil showed the concentration profiles for three different feed flow rates. The speed, temperature and thickness profiles of the liquid film were obtained. The speed of the film increases as the fluid flows through the walls of the evaporator, reaching a maximum on length of 0.075 m. The film thickness decreases on the route, since many compounds are volatilized. The result of the temperature profile had to be consistent with the literature reproduced, being constant after reaching the maximum operating temperature in the length of 0.15 m. This study allowed characterizing and focusing, through experimental analysis, unsaturated compounds and observing the sunflower oil´s behavior through process simulation.
Resumo:
This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.
Resumo:
This work proposes a new autonomous navigation strategy assisted by genetic algorithm with dynamic planning for terrestrial mobile robots, called DPNA-GA (Dynamic Planning Navigation Algorithm optimized with Genetic Algorithm). The strategy was applied in environments - both static and dynamic - in which the location and shape of the obstacles is not known in advance. In each shift event, a control algorithm minimizes the distance between the robot and the object and maximizes the distance from the obstacles, rescheduling the route. Using a spatial location sensor and a set of distance sensors, the proposed navigation strategy is able to dynamically plan optimal collision-free paths. Simulations performed in different environments demonstrated that the technique provides a high degree of flexibility and robustness. For this, there were applied several variations of genetic parameters such as: crossing rate, population size, among others. Finally, the simulation results successfully demonstrate the effectiveness and robustness of DPNA-GA technique, validating it for real applications in terrestrial mobile robots.
Resumo:
Steam injection is an oil recovery method accomplished by introducing steam directly into the oil well to the reservoir. The steam causes dilation of the casing, which, after reduction in temperature, tends to return to the initial dimensions: causing the formation of cracks in the cement and loss of hydraulic isolation.. In this context, the type of the SBR latex is used to improve the flexibility of the cement matrix by reducing the amount of fatigue failure. To prevent these failures, the mechanical resistance parameters should be carefully adjusted to well conditions. This work aims to study the mechanical behavior of cement slurry systems additivated with SBR latex for cementing oil wells subject to steam injection. Through the central composite factorial design was studied the behavior of the compressive strength by varying the density of the paste between 1.75 g /cm³ (14.6 lb/ Gal) and 1.89 g/cm³ (15,8lb / Gal), curing time between 4 days and 28 days and concentration of SBR Latex between 0 L / m³ and 534.722 L / m³ (0 gpc and 4 gpc). The results showed that increasing the concentration of SBR latex, within the given ranges, there was a decreased compression resistance and elastic modulus by increasing the elastic deformability of the slurry. From the results it can determine best slurries formulation conditions in oil well cementing operations subject to steam injection.
Resumo:
Steam injection is an oil recovery method accomplished by introducing steam directly into the oil well to the reservoir. The steam causes dilation of the casing, which, after reduction in temperature, tends to return to the initial dimensions: causing the formation of cracks in the cement and loss of hydraulic isolation.. In this context, the type of the SBR latex is used to improve the flexibility of the cement matrix by reducing the amount of fatigue failure. To prevent these failures, the mechanical resistance parameters should be carefully adjusted to well conditions. This work aims to study the mechanical behavior of cement slurry systems additivated with SBR latex for cementing oil wells subject to steam injection. Through the central composite factorial design was studied the behavior of the compressive strength by varying the density of the paste between 1.75 g /cm³ (14.6 lb/ Gal) and 1.89 g/cm³ (15,8lb / Gal), curing time between 4 days and 28 days and concentration of SBR Latex between 0 L / m³ and 534.722 L / m³ (0 gpc and 4 gpc). The results showed that increasing the concentration of SBR latex, within the given ranges, there was a decreased compression resistance and elastic modulus by increasing the elastic deformability of the slurry. From the results it can determine best slurries formulation conditions in oil well cementing operations subject to steam injection.
Resumo:
Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO•) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R² = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R² = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.