Browsing by Issue Date, starting with "2012-07-27"

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Determinação voltamétrica de fibratos em formulações farmacêuticas utilizando eletrodos de carbono vítreo modificados com nanotubos de carbono
(Universidade Federal de São Carlos, 2012-07-27)
Quintero, Jorge Armando Ardila
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Fatibello Filho, Orlando
;
https://lattes.cnpq.br/9859737944357808
;
https://lattes.cnpq.br/2093399167811012
In this work voltammetric methods were developed from gemfibrozil (GEM) and bezafibrate (BZF) determination in pharmaceutical formulations for using modified glassy carbon electrode with dihexadecyl hydrogen phosphate containing carbon nanotubes treated chemically. Firstly was studied the voltammetric behavior of GEM in 0.1 mol L 1 (pH 2.0) phosphate buffer solution, was observed an irreversible oxidation peak in 1.31 V. Square-wave adsorptive stripping voltammetry was selected for GEM quantification in pharmaceuticals formulations, with the following parameters: adsorption time of 300 s, frequency of 40 Hz, a pulse amplitude of 45 mV and scan increment of 4 mV. The analytical curve was linear over the concentration range of 7.5 × 10−8 a 1.0 × 10−6 mol L−1 of GEM, represented by following ΔI (μA) = 0,086 + 1,05 × 107 [GEM] (mol L 1), correlation coefficient of 0.997 and detection limit of 5.3 × 10−8 mol L−1. The procedure developed was successfully applied to determine GEM in commercial pharmaceutical samples and the results were compared with the reference method, described in British pharmacopoeia. There was no significant difference (5 %) between the results obtained at a confidence level of 95%. The BZF determination was carried in 0.1 mol L 1 (pH 2.0) phosphate buffer solution and an irreversible peak in 1.09 V was observed. Square-wave adsorptive stripping voltammetry technique was selected for BZF determination with the following parameters: adsorption time of 180 s, frequency of 20 Hz, pulse amplitude of 40 mV and scan increment of 7 mV. The proposed method presented a linear interval between 5.0 × 10−8 a 9.1 × 10−7 mol L−1 and detection limited of 1.6 × 10−8 mol L−1. The BZF was quantified in commercials samples and the results were compared with de spectrophotometric method, with errors between 2.9 e 0.5 %. Finally for each analyte were calculated the number of electrons involved in the oxidation reaction and was proposed a possible mechanism for the oxidation reaction of these drugs, because there are no reports in the literature.
Estudo do comportamento termomecânico e análise da formação de orientações preferenciais de aços com 6,5% Si conformados por spray
(Universidade Federal de São Carlos, 2012-07-29)
Bonon, Felipe Rehder
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Jorge Júnior, Alberto Moreira
;
https://lattes.cnpq.br/6360362248108490
;
https://lattes.cnpq.br/2825402118400386
Termomechanical behavior of spray formed 6.5% Si-Carbon steels were analyzed by physical simulation, through torsion tests, and the evolution of preferential orientation were analyzed in order to electrical devices. Low carbon steel was used in spray forming, and the parameters were changed in order to minimize porosity. The carbon content in Specimens influence in hot mechanical behavior were analyzed in torsion tests in only one pass until fracture, in warm temperatures ranging from 700 °C to 930 °C in a specific strain rate of 1s-1. Microstructure evolution was analyzed in SEM (scanning electron microscope) and the texture through EDSD (electron backscatter diffraction). Results shows that alloy ductility are improved with the carbon contents and process used, temperature and strain rate, and in some processes conditions preferential orientation necessary in electrical devices is obtained.
Concretos refratários contendo agregados eutéticos eletrofundidos: energia de fratura e a resistência ao dano por choque térmico
(Universidade Federal de São Carlos, 2012-07-30)
Miyaji, Dan Yushin
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Rodrigues, José de Anchieta
;
https://lattes.cnpq.br/4000441989868775
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https://lattes.cnpq.br/4150977564959773
The use of fused alumina-zirconia and mullite-zirconia eutectic aggregates can be an interesting choice to toughening high alumina castables, in order to produce good thermal shock damage resistant material. As a remarkable characteristic, the applying of such aggregates results in high fracture energy values, as a consequence of complex crack propagation process through the eutectic microstructure. However, the understanding of the relation between fracture energy and thermal shock damage requires special care, eventhough such relation is prospected by very know mathematical models. This is because the correct choice of sample dimentions showed to be very important to find relations between Hasselman s R -parameter and the experimental resistance to thermal shock The general results have indicated that the materials of the highest fracture energy values presented the highest thermal shock damage resistance. It was also verified that a high amount of aggregates in the castables did not produce reiforced microstructures, but more flexible materials, in a sense that the material s tolerance to crack opening had increased. This result is considered important because it shows that aggegates may play other roles besides the conventionaly known ones.
Um procedimento para investigar aprendizagem discriminativa e formação de classes funcionais em cães (Canis familiaris)
(Universidade Federal de São Carlos, 2012-07-30)
Montagnoli, Tathianna Amorim Souza
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Souza, Deisy das Graças de
;
https://lattes.cnpq.br/4404800720856419
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https://lattes.cnpq.br/3348580978835319
The investigation of symbolic or pre-symbolic behavior in dogs requires the establishment of arbitrary relations among stimuli. A way to teach such relations is requiring a common response in the presence of each one of them, which can result in a class of functionally equivalent stimuli. This study aimed to investigate the formation of functional classes with four dogs. For this purpose it was used an automated device for emission and recording of operant responses and for the presentation of visual stimuli. The operant response was to nose poke a stimuli which were presented in a touch-screen monitor. Three sets of two stimuli (A1/A2; B1/B2; C1/C2) were used for three dogs and two sets of two stimuli (C1/C2; E1/E2) were used for the other dog. In each set, one stimulus was related to reinforcement (S+) and the other to extinction (S-), regarding tasks of simultaneous simple discrimination. Five experimental phases were programmed for three dogs: I) Training and reversals of pair A stimuli; II) Training and reversals of pair B; III) Training and reversions of AB being presented in the same session with functional class formation probes; IV) Training and reversals of pair C; and V) Training and reversals of ABC with functional class formation probes. On the third and fifth phases stimuli of the same set (A1 and B1 or A1, B1 and C1, respectively) were established as S+, and the stimuli of the other set (A2 and B2 or A2, B2 and C2) as S-. After baseline was acquired and reached stability the functions of the stimuli were reversed repeatedly (S+ began to function as S- and vice versa), and it was appraised if the animals reverted the functions of the other stimuli given the reversal of the first pair in one of the sets, and that before direct exposure to new contingencies which would indicate functional classes formation (S+ class and S- class). For the fourth dog four experimental phases were programmed: I) Training of pair E stimuli (without reversal); II) Training of pair C stimuli; III) Training of CE being presented in the same session; and IV) Three reversions of CE being presented in the same session. The results show that the procedure was able to establish a complex and flexible discriminative repertoire in dogs, but insufficient to demonstrate relational responding in the only animal to be exposed to the functional class probes. Nevertheless, considerations were made about the positive aspects of the proposed procedure and learning set formation.
Uso de recursos estimuladores da aprendizagem significativa no ensino de física
(Universidade Federal de São Carlos, 2012-07-30)
Santos, Ernani dos
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Chiquito, Adenilson José
;
https://lattes.cnpq.br/7087360072774314
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https://lattes.cnpq.br/8427875981262711
This research deals with resources which lead to significant learning consistent with the needs of modern society and encourages students to develop knowledge in Physics, in order to enable them to interact with the community in a critical and consistent manner towards an intellectual, economic and technological development in a conscious and sustainable way. Therefore, we studied teaching methods based on constructivism and meaningful learning, coupled with application of resources to explore the school environment and technologies related to education and practical application of Science in low cost experiments; in Science Museums and Thematic Parks; aiming to recover the values of the school and offer a new perspective on education for teachers and students, who pressed for mutual participation in the teaching-learning and highlight its importance in the progress of the nation.
Abordagem de recomendação baseada em conteúdo utilizando ontologia fuzzy de domínio e ontologia crisp de preferência do usuário
(Universidade Federal de São Carlos, 2012-07-30)
Baldárrago, Arturo Elias Urquizo
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Prado, Antonio Francisco do
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https://lattes.cnpq.br/2668568143800755
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https://lattes.cnpq.br/3757704078864558
This paper presents an approach for developing content-based recommendation applications with focus on the use of a specific domain fuzzy ontology along with a user preference ontology. The approach falls into two stages: Ontology Engineering and Recommendation System Engineering. In the Ontology Engineering, a domain ontology with fuzzy relationships and a user ontology are built. The user ontology is set as an instance of the domain ontology, but it is modeled in a way that allows to store each user s preferences. The usage of the ontologies produced in Ontology Engineering provides a gain in precision for the results obtained by applications in the Recommendation System Engineering stage. For evaluation purposes, we instantiated the proposed approach in the development of a Recommender System for the field of electronic commerce, focusing on the mobile devices commerce domain. Following the experimental methodology, An evaluation was conducted in order to assess the approach s impact on the accuracy of results provided by the developed Recommender System. The results showed that the use of our approach contributed to increase the accuracy of the results, in terms of prediction, classification and ranking. The contributions of this work include: the approach for developing content-based recommendation applications by using a specific domain fuzzy ontology along with a user preference ontology; the definition of the UPFON methodology, which integrates the approach, to construct fuzzy ontologies; an instantiation of a fuzzy ontology for the mobile devices domain and a strategy to capture; and propagate the user preferences by means of ontologies.
Agricultura orgânica e atores neorrurais na Serra da Mantiqueira: o grupo Orgânicos da Mantiqueira, Gonçalves, MG
(Universidade Federal de São Carlos, 2012-07-31)
Aun, Nádia Jarouche
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Norder, Luiz Antonio Cabello
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https://lattes.cnpq.br/0080353709980071
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https://lattes.cnpq.br/0241035860005136
This paper discusses the characteristics of the new rural population and their forms of action, based on the case of the Orgânicos da Mantiqueira group, they are localized at Gonçalves, MG. It is intended to discuss the new forms of occupation in rural areas played by those new actors and the multiple functions assigned to them. Therefore It will be analyzed the construction of this new ruralities and the different ways of occupying a land marked by traditional customs. Within this context It will be underlined the differences between rural and urban occupation. The land occupation is approached from the concept of the agriculture multifuncionality. It will be taken into account the peculiarities of the new rural population s productive and organizational characteristics besides their interactions with local populations in rural reconstruction and the evaluation of the area through new ecologic agricultural basis. Starting from the history of the ecological movement in rural areas, the ecological agriculture is studied through the analysis of the agroecological conversion systems. There will be pointed out some relevant issues related to the crop systems management in the visited areas as well as the critical points affecting the realization of the Orgânicos da Mantiqueira s productive activity. It can be perceived at the end that the constitution of a group and its institutionalization upon society happens by collective desire and common objective considering, during its process, the emergence of new contradictions.
Simulação dinâmica do processo de destilação de bioetanol em simulador baseado em equações (EMSO)
(Universidade Federal de São Carlos, 2012-07-31)
Silva, José Izaquiel Santos da
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Giordano, Roberto de Campos
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https://lattes.cnpq.br/9481859974252755
Distillation of hydroalcoholic mixtures that result from the fermentative route of production of ethanol has been widely studied. Nonetheless, three points have not deserved special attention yet: the industrial fermentation intrinsic variability; the changes on the feed stream of the columns caused by the mixing of 1st (1G) and 2nd (2G) generation wines in the same biorefinery; and the alteration of the level in the buffer vat throughout the operation of the industrial plant. The two first aspects result in changes of the concentration of ethanol and other fermentation by-products, such as isoamyl alcohol in the buffer tank. The third aspect alters the flow impelled by the feed pumps and, consequently, changes the outlet temperature of the K heat exchanger (i.e. of the first column feed stream). In this work, the EMSO simulator (Environment for Modeling, Simulation and Optimization) was used to study transient perturbations of the columns operation, and the effect of wine composition in the buffer vat that will be pumped for distillation, with aid of a column model representing the distillation train A-A1-D. Reboiler and condenser temperatures and levels are controlled by PID loops, and the dynamic model of the tray column includes correlations (already implemented in EMSO) for liquid holdup, pressure drop in the tray, among other aspects. The gamma-phi approach, using UNIFACDortmund equation for the liquid phase non-ideality and SRK model for the vapour, was used to represent vapor-liquid equilibrium (VLE). Firstly, the dynamics of distillation of ethanol-water and ethanol-water-isoamyl alcohol mixtures was simulated, up to steady state. The EMSO steady-state results were very similar to Aspen-Pus® (7.3) simulations. Following, in order to closer represent the complexity of the real situation, a model of the centrifugal pump plus tabulation was inserted in EMSO, integrated to the K heat exchanger (that regenerates the energy of vinasse, pre-heating the column feed) and to the column itself. The main conclusions were: the presence of isoamyl alcohol influenced somehow the temperature and molar fractions transient profiles in the column, but the composition of the top stream was not sensibly affected. Changes of the liquid level in the buffer vat during the operation, following loadunload cycles, caused periodic perturbations in the system output variables (flows, temperatures and mol fractions of the process outflow), whose amplitude could be absorbed by the control system. Step perturbations in the buffer vat were simulated, with consistent responses, as assessed by the system global mass balance. Mixing wines with lower alcoholic contents, as the ones coming from the 2G process, causes effects that are dumped after one load-reload cycle of the vat. In long term, model responses indicate that, kept the reflux ratio and the top and bottom conditions in the column, the system gradually achieves stable operation points.
Caracterização de poli(hexametileno biguanida) e suas blendas com poli(álcool vinílico)
(Universidade Federal de São Carlos, 2012-07-31)
Paula, Gustavo Figueira de
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Mattoso, Luiz Henrique Capparelli
;
https://lattes.cnpq.br/5839043594908917
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https://lattes.cnpq.br/0634496933960503
In this study, the physical-chemical characterization of poly(hexamethylene biguanide) hydrochloride, PHMB, was performed. It is a low molecular weight synthetic polymer with a broad-spectrum biocidal activity, widely used in aqueous formulations for industrial purposes. Dynamic Light Scattering, Thorque Reometry, Electrical Impedance Spectroscopy, Goniometry, UV/Vis Spectroscopy and Differential Scanning Calorimetry were used to probe the solvent-polymer interaction, determining that the properties presented by the material are strongly influenced by the nature of interactions between the hydroxyl groups of the solvent and the counter ion chloride from polymer. The polymeric nature of the material does not change the behavior of the biguanide group, whose properties remains unchanged compared to those of equivalent monomeric moiety, as evidenced by the formation of complexes with transition metals in nature very similar to biguanide and its derivatives. The polymer in solution behaves largely as a surfactant, and the tendency of micelle formation affects their film-forming properties. Blends with poly(vinyl alcohol) with high degree of hydrolysis (99%), PVOH, were studied by DSC, XRD, FTNIR, Thorque Rheometry and Electrical Conductivity; it showed miscibility in amorphous state, exhibiting regular solution behavior. The blends were semicrystalline up to 30% of mass fraction, composed by PVOH crystals with small inclusion of PHMB. The hypothesis that PVOH behaves as a solid solvent for PHMB was confirmed, which looks very useful for studying the properties of the latter aiming the development of new applications for this material. Electrospun mats of nanofibers were produced, and after further improvements, can be used as auxiliary treatment to heal wounds and external cirurgical interventions.
Diretrizes para licitações de projetos de sistemas prediais de água fria e esgoto sanitário em campi universitários
(Universidade Federal de São Carlos, 2012-07-31)
Cover, Marcelo Pinarelli
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Amorim, Simar Vieira de
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https://lattes.cnpq.br/8264867164852836
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https://lattes.cnpq.br/5247659674516849
In the context of the plumbing systems, the design stage may be responsable for considerable parcel of pathological manifestations that may occur after the building occupation. These problems can bring negative impact for the users, considering the built environment, and also demands premature maintenance with respective extra costs, which may decrease the building lifetime. In this context, this dissertation aims to propose guidelines that can be used in the bidding for projects of building systems of cold water and sanitary sewer in university campuses. The method used for the research was the case study. Firstable, a bibliographic survey was carried out by addressing the systems studied, the concepts of performance evaluations, as well as a collection of studies on pathologies, that had served to appraise the work. The guidelines, final result of this research, was developed, based on a survey of criteria and performance requirements present in the NBR 15575: 2008 Residential buildings of up to five floors Performance (ABNT, 2008), and based else in the author experience in the area. After that, two projetcs on Campus Are Carlos from the Federal University of São Carlos were analysed, as practice demonstration of the obtained results.
Desenvolvimento de formulações de Bacillus subtilis para controle da podridão floral em citros
(Universidade Federal de São Carlos, 2012-07-31)
Klein, Mariana Nadjara
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Kupper, Katia Cristina
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https://lattes.cnpq.br/7900622063392740
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https://lattes.cnpq.br/9729133101595180
Brazil is the world's largest producer of orange, seated in an area of 839.000 hectares, of which 77% are located in the southeast. Despite the importance of this crop, the citrus industry faces serious problems represented by fungal diseases that reduce productivity such as citrus post-bloom fruit drop (PDF), caused by Colletotrichum acutatum. As control is predominant spraying chemicals. Considering the financial costs, environmental damage and public health of these applications, it is necessary to study new control alternatives, and among these, the biological control. Therefore this study aimed to develop a formulation of Bacillus subtilis, based different transport vehicles, with or without additives, aiming to control the PDF. The results showed that the powder as a vehicle for transport, provided a greater viability of bacterial cells stored in the two temperatures tested (1 and 22 ° C) for a period of 12 months. In vitro tests showed that the powder plus urea (0.02%) inhibited both the mycelial growth, as the germination of C. acutatum. The additives urea (0.02%) and ammonium molybdate (1mM) optimized the formulation, when tested in the same flower deployed. Control data under field conditions, showed that B. subtilis in powder plus urea (0.02%) yielded 72.7% of flowers without infection by the pathogen and 56.4% of the average number of effective fruits (ANEF) and on the other hand, the control treatment was obtained 8.8% flowers and 0.83% of healthy ANEF, chemical treatment (thiophanate-methyl) showed 69.6% of healthy flowers and 46.7% ANEF. It is concluded that, based formulation B. subtilis, with talc as a transport vehicle, plus an additive (urea 0.02%) kept the viability of bacteria cells and was effective in the controlling of disease.
A repercussão pública da participação do Brasil na Minustah (2004-2011)
(Universidade Federal de São Carlos, 2012-08-02)
Gonçalves, Israel Aparecido
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Martins Filho, João Roberto
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https://lattes.cnpq.br/9604222489577177
The object of this work is to analyze the public impact of Brazil's participation in the MINUSTAH - United Nations Stabilization Mission in Haiti. To understand the public impact we have studied three fields: academe, Congress and the written press in Brazil. The methodology of this study was guided by intensive reading of essays and papers about the Brazilian participation in MINUSTAH and analysis of primary sources, such as laws and official documents. The results show there is a positive public image of the Brazilian participation in MINUSTAH, even with some critical periods.
Desenvolvimento de blendas nanoestruturadas SAN/PBT modificadas com copolímeros acrílicos reativos
(Universidade Federal de São Carlos, 2012-08-02)
Costa, Lidiane Cristina
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Hage Júnior, Elias
;
https://lattes.cnpq.br/1240692926327687
;
https://lattes.cnpq.br/8246109223926480
In this work we have obtained transparent nanoblends of poly(styrene-coacrylonitrile) (SAN) as matrix and poly(butylene terephthalate) as a nanometric phase. The materials were produced by means of reactive mixing in a twin screw extrude. The development of compatibilization systems, in order to diminish the dimension of dispersed phase in situ, can be seen as a great scientific challenge in nanoblends field. In such case, the compatibilizer optimizes the comminution and prevents the coalescence process of the dispersed phase. The compatibilization between SAN and PBT phases was performed using terpolymers of methyl methacrylate (MMA), glycidyl methacrylate (GMA), and ethyl acrylate (EA), denoted as MGE. Using bulk polymerization, we have applied different conditions for compatibilizer syntheses, in order to achieve a decreasing in the MGE molecular weight. The analyses of the reactivity of different compatibilizer with PBT were accomplished by using both torque rheometry and transmission electron microscopy. We have noticed that as the molecular weight of MGE decreases, the particles sizes of the dispersed phase diminishes accordingly. This part of the study culminated in the selection of the better MGE for nanoblends production. Blends with concentration varying from 3 to 30% wt were prepared in an extruder. These nanoblends were characterized with respect to thermal, dynamic-mechanical, rheological, mophorlogical and optical properties. We have shown that the MGE incorporation presents a high-efficiency for the decreasing of the PBT domains and plays an important role for the optical properties of the resulting nanoblends.
Ocorrência de bactérias endofíticas na cultura do pinhão manso (Jatropha curcas L.)
(Universidade Federal de São Carlos, 2012-08-02)
Schmidt, Vitória Anselma
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Gerald, Lee Tseng Sheng
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https://lattes.cnpq.br/1013931203340055
The endophytic microorganisms inhabit the interior of the plants, being found in organs and tissues such as leaves, stems and roots without causing disease or producing visible external structures. The endophytic community consists mainly of bacteria and fungi that unlike pathogens, can benefit the plants, however, depending on conditions such as interaction between bacterial communities, competition for nutrients, it can become pathogenic. The endophytic community has been evaluated in many plants, especially in studies with diazotrophic bacteria. In this study, endophytic bacterial diversity of leaves, stems and roots of physic nut (Jatropha curcas) were studied using morphologic, physiological, biochemical and molecular markers, such as 16S rDNA. The samples were disinfected (removing epiphytic microorganisms), macerated and serially diluted to obtain the suspensions that were inoculated into culture media selective for diazotrophic microorganisms. The plates were incubated at 30°C for seven days. Forty-six colonie s were isolated, with 19 in the leaves, 11 in the stems and 16 in the roots. DNA of these endophytic bacteria purified was isolated, purified and the Y1-16S805 portion of the 16S rRNA gene was amplified and sequenced. Analysis of sequence identity were made by the programs BLASTn, CLUSTALW and phylogenetic analyzes by MEGA5. The roots showed greater diversity of endophytic microorganisms, with seven of the eight genera identified. In the leaves and in the stem, six genera were identified, respectively. In leaves, the exception was the genus Salmonella and Serratia. In the stem, Serratia, and in the roots more than one species of the genera Acinetobacter were found. The genera Bacillus and Burkholderia were found more frequently in all regions sampled. The genus Bacillus in the leaves, stems and roots accounted 20, 4 and 4%, respectively, of the total endophytic microorganisms identified. From the total isolates of the genus Bacillus, 73% belonged to the species B atrophaeus, B. brevis and B. sphaericus, the other 27% belonged to group B. cereus. These results suggest that the endophytic bacteria diversity of physic nut is large. Microorganisms identified in this work have potential for growth promotion, biological control and nitrogen fixation, as they were isolated in selective media with low concentration of nitrogen, in addition there are reports in the literature about the benefits of them for different plants.
Desenvolvimento de nanoblendas poliméricas PMMA/SAN
(Universidade Federal de São Carlos, 2012-08-03)
Ternes Neto, Alvaro
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Hage Júnior, Elias
;
https://lattes.cnpq.br/1240692926327687
;
https://lattes.cnpq.br/0814243517392991
The motivation for this work was the idea that nanoblends are fundamentally dependent on the high interaction between the phases in the mixture. The strategy adopted in this study was based on the use of two polymers that have a miscibility window, which allows the establishment of an immiscibility condition very close to the limit of this window, providing low interfacial tension between phases. Nanoblends of poly(methyl methacrylate) (PMMA) as the matrix and poly(styrene-co-acrylonitrile) (SAN) as the nanophase were obtained by blending in a twin screw extruder. The compatibilization between the phases was accomplished through the incorporation of the terpolymer (MGE) synthesized from the monomers methyl methacrylate (MMA), glycidyl methacrylate (GMA) and ethyl acrylate (EA). The morphology of the blends was characterized by transmission electron microscopy (TEM). The transparency of the blends and pure polymers was quantified by transmittance of visible light. Tests such as torque rheometry, capillary rheometry, tensile strength and chemical resistance to solvents were also performed. Nanoblends with 1 and 3 wt% of the dispersed phase were obtained in the absence of MGE. The introduction of the terpolymer allowed a significant reduction of the SAN phase for compositions with 5 and 10% by weight. Through this reduction blends with 5 wt% of SAN reach the nanoscale. It was found that blends transparency is directly related to the dispersed phase mass fraction. Blends mechanical properties were close to those of the PMMA. Blends and pure polymers did not swell by the solvents chosen.
Efeito da abundância das aves granívoras sobre a predação de sementes pós-dispersão em fragmentos florestais da Mata Atlântica
(Universidade Federal de São Carlos, 2012-08-03)
Menezes, Gregório dos Reis
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Hasui, Erica
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Christianini, Alexander Vicente
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https://lattes.cnpq.br/2295622727813765
;
Silva, Fernando Rodrigues da
Mineração de regras de associação sequenciais em séries temporais e visualização: aplicação em dados agrometeorológicos
(Universidade Federal de São Carlos, 2012-08-03)
Cano, Marcos Daniel
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Ribeiro, Marcela Xavier
;
https://lattes.cnpq.br/0300141044144026
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https://lattes.cnpq.br/9695321755996994
Technological development brought improvements in the technology of climate sensors and Earth's surface image acquisition, gathering increasing amounts of data. Generally, when these data are submitted to mining algorithms, the output is the production of hundreds or even thousands of textual patterns, making the task of data analysis by the domain expert even harder. Hence, it is crucial, to support experts, the development of a tool that helps to identify and display patterns of interest. In this context, this research project at Master Science level aims to develop a technique for mining association rules in time series allowing agrometeorological data analysis over time.
Riqueza e abundância de espécies em diferentes compartimentos da comunidade vegetal no gradiente fisionômico do Cerrado em Assis, SP
(Universidade Federal de São Carlos, 2012-08-03)
Neri, Ana Carolina Abrão
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Matos, Dalva Maria da Silva
;
https://lattes.cnpq.br/4728734263109138
;
https://lattes.cnpq.br/7641978829218060
Fire protection has caused ongoing changes in savannas throughout the world, with the expansion of the woody component over more open vegetation. Although these changes have been documented at the landscape level, some questions regarding changes in the floristic composition of communities and the regeneration mechanisms present in different physiognomies remain. The aim of this study was to evaluate species richness and abundance in several components of the community (seed rain, seed bank, and the understory, intermediate, and upper strata) in a cerrado area after 50 years of fire protection. This research was developed along the physiognomic gradient (typical cerrado, dense cerrado and cerradão) existent at Assis Ecological Station, São Paulo state. Seed rain, seed bank, and floristic composition of the three strata were sampled in 30 20 x 50 m plots, 10 plots in each physiognomy. Differences between physiognomies and between seasons were analyzed by means of uni- and multivariate analysis of variance and by linear regression and correlation. Basal area was used as a surrogate of biomass along the physiognomic gradient. Species richness decreased across the whole community for the ground layer and intermediate layer along the successional gradient. In seed rain and seed bank, the floristic composition and abundance differed significantly between the three physiognomies. In seed rain, trees and saplings, mostly generalist species, represented the predominant growth forms, both in relative abundance, as in richness. In the seed bank, herbaceous species presented the highest values for richness and abundance in all physiognomies. The seed rain and seed bank are important as regeneration strategies for a group of species, usually generalists. The homogenization of vegetation structure and floristic composition puts under question the management strategies currently employed in areas designed for Cerrado conservation. Considering that Cerrado fragmentation has concentrated its gene pool in small, isolated remnants and that some plant and animal species are restricted to more open physiognomies, a more refined discussion of the implications that management regimes may have on these communities is essential.
Desenvolvimento de compósito de policloreto de vinila (PVC) reforçado com fibra de vidro
(Universidade Federal de São Carlos, 2012-08-06)
Araújo, Daniela Gomes de
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Hage Júnior, Elias
;
https://lattes.cnpq.br/1240692926327687
This work was focused on the evaluation of the interface between short fiber glass and polymeric matrix of the PVC composites using four different sizings as fiber superficial treatment. The interface analysis was done through mechanical properties study and scanning electron microscospy (SEM), while compared with unreinforced PVC compound. The PVC formulation was mixed in a mixer and, after that, 10% in weight of 4 mm fiber glass was introduced and mixed manually in the compound. The initial plan was prepare plates of the glass reinforced PVC samples through a single screw extruder to get parts for analysis, however, this process was not enough to homogenize the fibers in the PVC matrix. Due to it, a new plan was defined and the plates were milled, it was processed in a double screw extruder to obtain pallets and parts for analysis were molded through injection molding. The results attained suggested that, all superficial treatments evaluated showed satisfactory adhesion between the fiber glass and PVC matrix, besides showing an excessive fiber length reduction due to the composite processing with consequent reduction of fiber performance.
Fabricação e caracterização de dispositivos baseados em nanofitas de Óxido de Estanho (SnO2)
(Universidade Federal de São Carlos, 2012-08-06)
Araujo, Luana Santos
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Chiquito, Adenilson José
;
https://lattes.cnpq.br/7087360072774314
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https://lattes.cnpq.br/8776491740006506
The structural and transport features of tin oxide nanobelts synthesized by the vapor-solid method combined with the carbothermal reduction process were investigated in this work. The samples synthesized were characterized by using experimental techniques such as scanning and transmission electron microscopy and x-ray diffraction. The nanobelts were found to be single crystals of rutile-type structure with a well defined growth direction. Electronic devices based on single nanobelt and on nanobelts dispersion were fabricated to measure the electronic properties of these samples. The semiconductor behavior was observed by the electron transport measurements data performed on a single nanobelt device, which pointed to the variable range hopping process as the main transport mechanism in a large range of temperature (77 K