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Estudo das propriedades fotoluminescentes de pós e filmes finos de MgTiO3 obtidos pelo método dos precursores poliméricos
(Universidade Federal de São Carlos, 2011-02-07)
Ferri, Elídia Aparecida Vetter
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Longo, Elson
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https://lattes.cnpq.br/9848311210578810
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https://lattes.cnpq.br/5272341911788626
In this study, MgTiO3 (MTO) powders and thin films that crystallize in a perovskite ilmenite crystalline structure were obtained and characterized. MTO were synthesized by the polymeric precursor method (PPM), which allows obtaining structurally ordered and disordered structures. In addiction, the photoluminescent properties were investigated as a function of the heat treatment temperature. MTO powders were heat treated at several temperatures ranging from 400 to 1300 °C for 2 h and characterized by X-ray diffraction (XRD), Micro Raman (MR) spectroscopy, termogravimetric and termodifferential analysis (TA), X-ray absorption near edge structure spectroscopy (XANES), ultraviolet-visible spectroscopy (UV-Vis), field emission gun scanning electron microscopy (FEG-SEM) and photoluminescence spectroscopy (PL). These techniques allowed observing the evolution of the phases, morphology as well as the structural order and disorder of the MTO samples. XRD and TA results indicated that the MTO ordered and pure phase was obtained at 600 °C. The photoluminescent property of structurally ordered and disordered MTO powders were studied at room temperature, using the excitation wavelength of 350.7 nm. Structurally disordered MTO present broad PL band of emission, while ordered MTO present a photoluminescent emission in red and infrared region of the spectra due to the tilt between complex clusters. XANES spectra showed in the disordered powders the coexistence of sixfold and fivefold titanium coordination. A correlation between the coexistence of these two types of coordination for the titanium atoms and PL was proposed. MTO thin films were obtained by spin coating of the polymeric solution on Pt/Ti/SiO2/Si substrates using a rotation speed of 7000 rpm, for 30 s and heat treated at temperatures ranging from 400 to 700 °C. MTO thin films properties were investigated by XRD, UV-vis, MR, atomic force microscopy (AFM) and PL measurements. It was verified that MTO thin films began to crystallize at 550 °C, characterized by the presence of (110) diffraction peak of the MTO structure. The analysis of experimental techniques was possible to correlated PL properties with order-disorder at short and long range and the MTO thin films morphology.
Autogestão e tecnologia em cooperativa de catadores/as de resíduo: uma análise intersubjetiva sob a óptica do campo ciência, tecnologia e sociedade
(Universidade Federal de São Carlos, 2011-02-07)
Franceschini, Guilherme
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Machado, Maria Lúcia Teixeira
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https://lattes.cnpq.br/5703683100332513
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https://lattes.cnpq.br/7065590687454402
The current society presents sharp inequalities, based on competition and individualistic values. Aiming to break up with such values which result in unemployment, poor working conditions and social exclusion, the solidarity economy brings elements such as solidarity, cooperation, self-management. Given this reality, we highlighted a class of informal workers, called waste pickers , responsible for collecting about 90% of the waste directed to recycling plants in Brazil. Besides having a role in the economy, the waste pickers have specific knowledge and skills necessary to identify, collect, sort, add value and sell that waste. This case study, focused on the Coopervida, a waste pickers cooperative of São Carlos-SP, adopted a qualitative approach and intended to identify according to the view of the waste pickers, what elements are transformers and what are obstacles for the autonomy in the work of the Cooperative, with a focus on self-management, the development of social technologies and on the process of socio-technical adequacy. According with the referenced theory in science and technology, the critical communicative methodology was used, with the realization of communicative groups as a technique for collecting primary data. The interaction between the researcher and the research subjects (one male and two female members of the cooperative) happened through the establishment of an intersubjective dialogue in which they participated from the point of defining the research question to the data analysis. As one of the results achieved we identified as the main transforming element, the recognition by the workers of the importance of cooperation, solidarity, participation in the activities of formation and adding value to waste to the self-management practices and the advance towards the Cooperative autonomy. The workers development of social technologies and the socio-technical adequacy process was also found to be an important transforming element for the autonomy in the work of Coopervida. In contrast, the lack of cooperation of some workers, the sometimes truncated communication between them, along with the difficulty in breaking up with the division of manual and intellectual work, expressed in the dichotomy between production and management, are the main obstacles to the Cooperative autonomy, since such actions are not directed towards the values of self-management that the venture is proposing to accomplish. We related the themes investigated with Science, Technology and Society field, through the participation of the research subjects in the production of knowledge and in the adequation of technologies with the objective of overcoming social inequality and in favor of the historically marginalized classes.
Ecologia de bandos mistos de aves na Estação Ecológica de Itirapina, Estado de São Paulo
(Universidade Federal de São Carlos, 2011-02-07)
Reis, Matheus Gonçalves dos
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Dias Filho, Manoel Martins
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https://lattes.cnpq.br/1346547036069954
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https://lattes.cnpq.br/2925754537368211
The degradation of natural grassland and open area remnants is still intense and affect environmental integrity of these ecosystems. The mixed-flocks of birds are a common feature in open environments which provide advantages to members. We aimed to analyze mixed-flocks of birds in three open physiognomies of cerrado to verify differences among sampled areas and periods. We believe that mixed-flock structure changes according to the physiognomy and between the seasons. We followed and record 337 mixed-flocks formed by 45 bird species between July 2008 and December 2010, in Estação Ecológica de Itirapina, São Paulo state. The flocks of campo limpo (grassland vegetation) had a lower participation of species than flocks from other areas, and structure did not varied significantly between breeding (summer) and non-breeding (winter) period. Two species formed flocks only in campo limpo . The campo sujo (grassland with scattered shrubs), considered an intermediate environment in our study, had no exclusive species. The seasonal variation in flock structure was significant. The campo cerrado (shrubby-grassland with many scattered trees) indicates the same differentiation between seasons. We found similarities between the breeding period of campo sujo and campo cerrado . Twelve species were present only in flocks of campo cerrado with low occurrence frequencies; all of them are birds of more wooded or forested environments. We categorized species according to their function played in mixed-flocks: True Leaders, Leaders/Followers, True Followers, Occasional Followers, Migrants. Five species played a role as True Leaders, and nine species can be considered as nuclear species of mixed-flocks. Saltator atricollis, Neothraupis fasciata and Cypsnagra hirundinacea were the most 29 common True Leaders. The formation of mixed-flocks, a phenomenon which benefits its members, were recorded in open areas of savanna throughout the year, but were especially important for birds during the period of resources scarcity. Nine flocking species, 20% of all species observed in this study, are threatened in São Paulo state and have high ecological relevance.
Caracterização da arborização viária e sua influência no microclima urbano na escala do pedestre
(Universidade Federal de São Carlos, 2011-02-07)
Giacomeli, Daniele Cristina
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Sales, Almir
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https://lattes.cnpq.br/7377787166073311
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https://lattes.cnpq.br/1905388664016081
The absence of appropriate conditions for the movement of pedestrians on sidewalks is degrading our human relationships of urban life and therefore the quality of life. There are several factors that determined the current situation of urban public walk among them are the actions without appropriate guidelines for implementation of these, the presence of random equipment, the network of electricity supply, the underground networks and also the deployment of nonspecific and irregular vegetation along the sidewalk. In this context, degradation of public space and the search for the recovery of several research areas that have been developed. Among the topics covered are: inventory methodologies, projects to bring the public footpath to the population needs, planning of urban trees and their various relationships, among others. This study aimed to examine, at a fraction of urban public spaces of the relations of way (sidewalk), are determined by a length of permanence, through microclimatic, tree inventory of the area and questioning passers-by, in order to understand the influence of urban trees on the microclimate on the scale of the pedestrian.
Influência térmica das configurações urbanas ao longo do eixo do Córrego Canela na cidade de São José do Rio Preto
(Universidade Federal de São Carlos, 2011-02-08)
Rocha, Luciani Maria Vieira
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Souza, Lea Cristina Lucas de
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https://lattes.cnpq.br/0083847008256434
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https://lattes.cnpq.br/2665625897264868
This research intends to investigate the influence of urban morphology in air temperature along the axis of Alberto Andaló Ave. and José Munia Ave., which border the Canela Stream in São José do Rio Preto. Initially, a review was made on the relationship between urban design and the influence of climate and vegetation on climate. Alongside, it was made a review of some existing studies on the expansion of the city, as well as on the occupation of streams margins by avenues construction. The cadastral and morphological data such as land use, topography, configuration of city blocks and lots, height of buildings and ground cover were surveyed in maps, either developed by the Municipality or obtained from satellite imagery and field observation. In order to collect temperature data, four points were chosen - two in José Munia Avenue and two in Alberto Andaló Avenue. The results of that field campaign at two measurement periods - the first in April and the second in July and August - revealed differences in the air temperature among the two avenues. The correlation of these data with the characteristics of land use and occupation showed a significant decrease of air temperature during the night due to the presence of vegetation and soil permeability, thus, minimizing the heat islands. Also, it was found that areas with high occupancy of buildings and intensely paved areas and city blocks lost less heat, leading to the formation of the highest heat islands during the night period.
Estudo da compactação de resíduos lignocelulósicos para utilização como combustível sólido
(Universidade Federal de São Carlos, 2011-02-08)
Chrisostomo, Walbert
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Botaro, Vagner Roberto
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https://lattes.cnpq.br/2907189124654066
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Yamaji, Fábio Minoru
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https://lattes.cnpq.br/4787449634914831
The production of energy from the combustion of lignocellulosic materials is an interesting way to waste recovery. Two main factors hampering the use of these residues as fuel are the low density and the high moisture content. Compression of lignocellulosic residues can be a way of producing solid fuel of better quality. The aim of this study was to evaluate the quality of solid fuels (briquettes) produced from the compaction of waste generated in lignocellulosic agroindustrial processes. The materials used in this study were: sugar cane bagasse, sawdust of Eucalyptus sp and sawdust of Pinus sp. The residues were compressed under the same conditions of particle size (particle size ranging from 20 to 40 mesh) and moisture content (10% dry basis). The compression was performed in a hydraulic press, without heating. The compaction pressure used was 1250 kgf.cm-2 and the time of application of the maximum load was 15 seconds. The production of briquettes was possible with the three types of materials used. The briquettes produced had densities ranging between 840 and 872 kg.m-3. This represented a volume decrease of 12.2 times for the sugar cane bagasse, 6.01 times for the eucalyptus and 5.28 times for the pine. The longitudinal expansion of the briquettes was 9.44% for the eucalyptus, 9.61% for the sugarcane and 10.76% for the pine. The results of diametral compression test were 1.01 MPa (eucalyptus), 0.61 MPa (cane) and 0.45 MPa (pine). The higher heating values (HHV) found were 4675 kcal.kg-1 (pine), 4436 kcal.kg-1 (eucalyptus) and 4138 kcal.kg-1 (cane). The results showed that all the materials tested can be used in the production of briquettes and the production of briquettes was possible by compression without heating. The compacting process improved the quality of solid biofuel.
Estudo comparativo das tensões na interface de compósitos de resina epóxi reforçados com fibras de carbono, aramida e vidro.
(Universidade Federal de São Carlos, 2011-02-08)
Nossa, Tamires de Souza
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Carvalho, Antonio José Felix de
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https://lattes.cnpq.br/5050955206618507
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Rubert, José Benaque
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https://lattes.cnpq.br/1726311467903505
Currently, composite materials are being used in several areas in substitution of some metallic alloys regarding to its superior properties and greater project flexibility. Therefore, synthetic fibers reinforced epoxy resin has some mechanical properties limited by its interface due to the interaction between fiber and matrix. The present research studies the interaction between the materials at the interface, considering the resin interaction with the three most employed composites fiber: carbon fiber, Aramida (Kevlar) and glass fiber (E type). The fibers surfaces were analyzed through the AFM (atomic force microscope) and the Contact Angle Method (CAM), becoming possible to determine the surface energy of each material, the superficial interface energy, the matrix-fiber adhesion and the surface profile analysis. The composites were subjected to the single fiber fragmentation test (SFFT) in order to obtain its interfacial share strength to be applied in the Kelly-Tyson equation. Furthermore, through these analysis became possible to evidence the properties differences between the composites, the individual properties of matrix-fiber that can be obtained, the best matrix-fiber interface, classifying them according to the stress transference magnitude and, consequently, greater effectiveness on the matrix-fiber adhesion.
Estudo das propriedades ópticas e morfológicas de pós de SrMoO4 processados em sistemas hidrotérmicos
(Universidade Federal de São Carlos, 2011-02-08)
Sczancoski, Júlio César
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Longo, Elson
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https://lattes.cnpq.br/9848311210578810
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https://lattes.cnpq.br/3260698029458172
In the last years, the luminescent emissions of SrMoO4 have been investigated for technological applications in solid-state lasers, light emission diodes, cell phone displays and lamps. In terms of synthesis routes, the hydrothermal systems have received special attention of the scientific community because of the versatility in the formation and crystallization processes of ceramic oxides at low temperature conditions (from 100 °C to 250 °C). Besides the reduced costs and environmentally friendlies, these methods are able to allow a control on the morphologies and particle sizes. Hence, in this research, SrMoO4 powders were synthesized by the co-precipitation reaction and processed in conventional and microwave-hydrothermal systems at 140 °C for 2 h. Thus, it was analyzed the influence of the hydrothermal conditions and the different strontium precursors on the optical and morphological properties of these powders. As experimental results, the X-ray diffraction patterns and the Raman-active vibration modes proved that all powders have a scheelite-type tetragonal structure. Diffraction peaks associated to the secondary phases were only identified in the samples prepared with strontium carbonate. The Rietveld refinements suggested the existence of distortions on both [SrO8] and [MoO4] clusters. The typical bending symmetric and stretching anti-symmetric modes between the O-Mo-O bonds were detected by the infrared spectroscopy. The field-emission gun scanning electron microscopy images revealed that the distinct strontium precursors as well as the hydrothermal conditions were able to change the microcrystal shapes. The adsorption/desorption isotherms showed profiles of type IV with hysteresis curves similar to the H3, suggesting the predominance of slit-like vacant spaces between the particles. The ultravioletvisible absorption spectra indicated the presence of intermediary energy levels within the band gap, which are arising from structural defects in the materials. xvi When excited with 350 nm wavelengths, all samples exhibited broad band photoluminescence emissions. Moreover, the profiles of these spectra were influenced by the precursors and/or hydrothermal treatments.
Desenvolvimento e avaliação de recurso educacional multimídia sobre fototerapia para orientação da família
(Universidade Federal de São Carlos, 2011-02-09)
Negré, Glaucia Regina Lopes
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Zem-Mascarenhas, Silvia Helena
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https://lattes.cnpq.br/0185144417072417
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https://lattes.cnpq.br/8043442384637549
Hyperbilirubinemia or jaundice is the result of overproduction or decreased excretion of bilirubin, this process can occur in newborns high or low risk. This disorder causes the appearance of a yellowish skin and sclera, and phototherapy the most common choice for treatment. The installation of phototherapy is part of routine care in hospitals, but for parents of newborns diagnosed with jaundice, this experience can be traumatic moment is central health education aimed at communication between nursing staff and parents procedures to which the newborn will be submitted. This study aims to develop and evaluate a multimedia educational resource on phototherapy guidelines for parents of newborns who will submitted to phototherapy to treat jaundice. This is an applied research that resulted in a multimedia educational resource entitled Phototherapy Orientations for the Family, which demonstrates the procedures necessary for the effectiveness of the treatment of jaundice. It is hoped that the results may support proposals for interventions and new research to assess the educational resource development.
A implantação da escola primária graduada em Presidente Prudente-SP: as contribuições das professoras primárias (1925-1938)
(Universidade Federal de São Carlos, 2011-02-10)
Mariano, Jorge Luís Mazzeo
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Hayashi, Carlos Roberto Massao
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https://lattes.cnpq.br/9136586124586219
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https://lattes.cnpq.br/5337334318541020
This study aimed to show what was the involvement of primary teachers in Presidente Prudente for the deployment of the First Group School of the city between 1925 and 1938, within the context of the history of Presidente Prudente and the feminization of teaching. The main objective was to present and analyze the implementation of the First School Group and which (which) was (were) a (as) contribution (contributions) for construction of teachers' schooling and the building of primary school graduate in Presidente Prudente. To achieve this goal, we collected data in literature sources (books, theses, dissertations) and documentary sources (Reports, Books of Exams, journalistic material, etc.), plus the use of semi-structured interviews with eight individuals, using as support the theory of Oral History, with Paul Thompson as references. As a result more evident from the survey, we saw that the struggle of primary teachers has contributed to building the first primary school in the city, and we concluded that the strategy was unsuccessful struggle of the teachers of Presidente Prudente (tuned with the larger movement of feminization of teaching ), since the execution of his work was done in an exemplary manner, as indicated in the records of / from ex-students, and their performance outside the school walls, even if not brought to the attention of children, was added to all the practices that enabled these students to the same opportunity to chart a future different from that of their mothers and grandmothers had.
Resultados de existência para as equações críticas de Klein-Gordon-Maxwell
(Universidade Federal de São Carlos, 2011-02-10)
Cunha, Patrícia Leal da
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Miyagaki, Olímpio Hiroshi
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https://lattes.cnpq.br/2646698407526867
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https://lattes.cnpq.br/2205687739599509
In this work we analyze the existence of radially symmetric solutions, positive solutions as well as the existence of ground state solutions for a class of Klein-Gordon-Maxwell equations when the nonlinearity exhibits critical behavior. For the positive and ground state solutions we prove existence results when a potential V is introduced. In order to obtain such results, we use variational methods
Conurbação e dispersão em aglomerações urbanas: desafios ao planejamento
(Universidade Federal de São Carlos, 2011-02-10)
Polidoro, Maurício
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Lollo, José Augusto de
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https://lattes.cnpq.br/8987677644041247
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https://lattes.cnpq.br/9713119960141699
Brazilian cities have gone through numerous setbacks in the last decades to house the bulk of the population is concentrated in these areas in search of a possible improvement in quality of life and economic opportunities. The unpreparedness of the municipalities to add all of this population is reflected directly in the environmental and social inequalities, the main characteristics of the cities. Those who concentrate the majority of the population - mostly urban agglomerations and metropolitan areas - are often those with the most obvious impacts and inequalities, with inadequate planning and management policies or the weak socioeconomic and environmental development. It is increasingly and evident the constant attempts of urban planners in creating mechanisms to control the use and occupation but, however effective they may be those regions with higher population density and strong traces of agglomeration and conurbation, usually do not develop mechanisms integrated planning of land use. In this sense, this proposal aims, through the use of Geographic Information Systems (GIS) to analyze the temporal process of formation of the urban area of Londrina (Paraná, Brazil) and evaluate, through development of subdivisions, zoning, provision of infrastructure and other relevant data how the inter-municipal relationships occurs and demonstrate that the lack of integration between the municipalities in the constitution of the instruments of control over the use and occupation of land can cause numerous impacts on the metropolitan and urban areas and as a consequence many difficulties for planning city.
Mobilidade e educação a distância: utilização de materiais audiovisuais para telas de baixa resolução
(Universidade Federal de São Carlos, 2011-02-10)
Oliveira, Alberto Geraissate Paranhos de
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Santiago, Glauber Lúcio Alves
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https://lattes.cnpq.br/9385173410103898
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https://lattes.cnpq.br/8488232017216581
This research is a case study about educational audiovisual materials produced specifically for low resolution screens devices, such as notebooks and netbooks, cell phones, MP4 players and similar, among others. A series of videos with this specification was produced and applied at a Musical Education class at UAB-UFSCar, Brazil. We conducted two surveys with students to evaluate the use of these videos. The first chapter presents a background about the emergence and spread of m-learning, which can be linked to broader changes in contemporary societies with the improvement and dissemination of information and communication technologies (ICTs) in what may be termed Digital Nomadism within the Information Age. We also present a discussion of guidelines adopted in distance education and the concept of educational technology. The second chapter presents the case study itself: the design, production, use and evaluation of a series of educational videos about music education, the Maximinivídeos. We also present the processes of pre-production, production and post-production of these videos, as well as an evaluation of its use in a distance education undergraduate course. In Chapter 3, we present the conceptual definitions and research procedures used in this work. It s an exploratory and descriptive research with a mainly quantitative approach of the data collected and which uses the case study strategy. The research also presents some conceptual and methodological affinity with Action Research and Middle-Level research methods and concepts. Finally, Chapter 4 presents conclusions about this research study, relating the concepts discussed in the literature review with the practice performed and the data collected, analyzed and organized. It is concluded that students are mostly receptive to mobile educational materials' incorporation. Those who still do not have such devices and/or who are not familiar with this kind of technology desire to explore this new universe. It is also noted that, although enthusiasts, students still prefer larger screen devices to watch and interact with educational materials. Lastly, discussions on mobility, education and audiovisual production, as well as notes for future research on the topics mentioned are also presented.
O processo de apropriação do desenho à escrita
(Universidade Federal de São Carlos, 2011-02-10)
Campos, Camila Torricelli de
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Reyes, Cláudia Raimundo
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https://lattes.cnpq.br/2307704502771843
The focus of this research is to understand how is the process of writing appropriation, while symbolic representation in children ranging between 5 to 7 years old. The study is longitudinal nature, characterized by analysis accounts developed in a long period of time. It was analyzed written productions of two children, already stored in a database during the period of 3 years. The theoretical framework was guided by the historical-cultural perspective, focusing authors like Vygotsky and Luria. Methodological assumptions were used as the evidential paradigm, to allow qualitative analysis. This paradigm was developed within the humanities and used to make assumptions about the development of graphic language of children, since the moment they begin to draw until to write. From the clues left in the productions collected, in search of understand the process of writing appropriation for these children. For this to be asked: What mark writing children 4 to 7 years leave in their graphic activities that indicate the process appropriation of writing? In order to answer this question was raised as a general objective describe and analyze the appropriation process of writing as the object of analysis marks leave on the graphic activities for children from 4 years until they the symbolic writing. It is worth noting there are few studies in the area of literacy with this character, and thus an important contribution into the topic, especially for studies of the historical-cultural theory. . It was possible to see in research throughout the course of written language acquisition, that the relationship between drawing and writing was linked to the need for children to express themselves when exposed to situations they might experience and show "some way" - drawing or writing - the useful and function of language. Autonomy in children's writing was when what they wanted to "say" couldn‟t be expressed only by his drawings. As they were appropriating this new language, writing, this became the main form of representation in their productions. The research may also contribute to the training area of literacy teachers, since their product can provide new ways for action towards the students.
Desenvolvimento de um reator fotoquímico microcontrolado, utilizando diodos emissores de luz (LEDs) como fonte de excitação luminosa
(Universidade Federal de São Carlos, 2011-02-11)
Possatto, João Fernando
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Batista, Alzir Azevedo
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https://lattes.cnpq.br/6469642481998660
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https://lattes.cnpq.br/0373507977334532
Aiming to contribute to the technological development of our country and meet the domestic demand for photochemical reactors, we have considered the possibility of developing a national product. The development of this project required the acquisition of knowledge to master the technology employed in the construction and application of photochemical reactors. This process was followed by refinement and implementation of the innovations that would make them more competitive and versatile to meet the demands of today s market. In the elaboration of the reactor, appropriate tools and the latest computing resources, comprising all stages of the project, namely structural design, loaded electronic and firmware were employed. Then it was possible to construct a virtual prototype with all the benefits of a real product, which enabled the construction of a physical one. As a result, the user could benefit from the combination of nice design and functional structure together with smart and efficient electronics and simple, intuitive interface. Results have proved not only the equivalence, but also the increase in the luminous efficiency through the substitution of the traditional radiation source of the fluorescent light by the LED light source (Light Emitting Diodes). So, through the implementation of the LED technology to this equipment, important and fundamental innovations were made, as follows. Clean, mercury-free and recyclable technology. Greater efficiency in turning electrical energy into luminous energy, leading to reduced electricity consumption and low heat generation. Greater durability of LED light sources, up to 1000 times higher when compared to fluorescent bulbs. Implementation of microcontroller systems, promoting control of luminous intensity, time-programmed excitation, temperature checking, graphical interface etc. The completion of this project resulted in the construction of a photochemical reactor which will bring a number of technological innovations to our country.
Modelo logístico generalizado dependente do tempo com fragilidade
(Universidade Federal de São Carlos, 2011-02-11)
Milani, Eder Angelo
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Tomazella, Vera Lucia Damasceno
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https://lattes.cnpq.br/8870556978317000
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https://lattes.cnpq.br/1420630122459706
Several authors have preferred to model survival data in the presence of covariates through the hazard function, a fact related to its interpretation. The hazard function describes as the instantaneous average of failure changes over time. In this context, one of the most used models is the Cox s model (1972), in which the basic supposition for its use is that the ratio of the failure rates, of any two individuals, are proportional. However, experiments show that there are survival data which can not be accommodated by the Cox s model. This fact has been determinant in the developing of several types of non-proporcional hazard models. Among them we mention the accelerated failure model (Prentice, 1978), the hybrid hazard model (Etezadi-Amoli and Ciampi, 1987) and the extended hybrid hazard models (Louzada-Neto, 1997 and 1999). Mackenzie (1996) proposed a parametric family of non-proportional hazard model called generalized time-dependent logistic model - GTDL. This model is based on the generalization of the standard logistic function for the time-dependent form and is motivated in part by considering the timeeffect in its setting and, in part by the need to consider parametric structure. The frailty model (Vaupel et al., 1979, Tomazella, 2003, Tomazella et al., 2004) is characterized by the use of a random effect, ie, an unobservable random variable, which represents information that or could not or were not collected, such as, environmental and genetics factors, or yet information that, for some reason, were not considered in the planning. The frailty variable is introduced in the modeling of the hazard function, with the objective of control the unobservable heterogeneity of the units under study, including the dependence of the units that share the same hazard factors. In this work we considered an extension of the GTDL model using the frailty model as an alternative to model data which does not have a proportional hazard structure. From a classical perspective, we did a simulation study and an application with real data. We also used a Bayesian approach to a real data set.
Um modelo de otimização para as operações de produção de vapor em caldeiras industriais: um estudo de caso na indústria de alimentos
(Universidade Federal de São Carlos, 2011-02-11)
Rocco, Cleber Damião
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Morabito Neto, Reinaldo
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https://lattes.cnpq.br/2127180000258691
The aim of this work was to develop and apply a mathematical optimization model to support some key decisions in the steam production operation system with multiple industrial boilers. In the food industry, key decisions into this system are, normally, taken based on people experience, not through decision support tools based on operations research. The proposed model approaches the fuel replenishment decisions, fuel transportation and fuel inventory management. The model also determines the start-up and shutdown moments for each boiler, as well as, which of them will produce steam. An algebraic modeling language was used to implement computationally the model, which was solved by an optimization software. The adjustments and model validation were performed through a case study carried out in a large scale food industry localized in Goiania (GO). In computational experiments conducted with company s data, the results obtained by the model showed better economic performance than those from the company. In face of the good outcomes obtained by applying the model and the lack of protocols or decision tools for the studied system, this model presents itself as a feasible alternative to be considered to support some key-decisions in the steam production system with industrial boilers.
Variação espacial e temporal da diversidade e biomassa da comunidade zooplanctônica do reservatório da UHE de Furnas-MG, Brasil
(Universidade Federal de São Carlos, 2011-02-11)
Silva, Lidiane Cristina da
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Rocha, Odete
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https://lattes.cnpq.br/7577441794992601
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https://lattes.cnpq.br/0980251001185976
The UHE Furnas Reservir is located in the state of Minas Gerais and it was built for hydroelectricity generation in 1963, although it is present used for multiple purposes. The zooplankton communities of freshwaters are composed by a variety of species belonging to several taxonomic (Cladocera, Copepoda, Rotifera, Protozoa, larvas de Insecta, Ostracoda, Turbellaria), and are all ecologically important. Many species can be indicators being highly sensitive of environmental conditions The aim of the present work was to analyse the spatial and temporal changes in the species composition, diversity and biomass of zooplankton community as well as their interactions with other environmental variables at the UHE Furnas Reservoir. Samplings were carried out each three months in 36 points in the reservoir, including the two major compartments: Sapucai and Grande dammed portions. Measurements of the main physical and chemical variables were carried out in situ and in the laboratory measurements of nutrients, suspended matter and chlorophyll a concentrations were performed. Zooplankton community was sampled by vertical net hauls with plankton net of 68 μm mesh size. Samples were analyzed regarding the species composition, numerical densities and community biomass. The results obtained indicated the water of the UHE Furnas Reservoir has oligotrophic conditions except in a locality upstream, in River Marimbondo compartment and others located distantly from the dam. The reservoir is thermally and chemically stratified regarding temperature and dissolved oxygen. There are also spatial changes and the reservoir can be divided in three major compartments: Sapucaí River compartment; central portion close to the dam and the northern River Grande compartment. Temporal fluctuations occurred for most variables, with strong differences among the dry and rainy periods. The species richness was high and some species were spatially segregated. Copepoda was the most abundant zooplankton group, both in numbers and biomass. The highest densities and biomass were found in the central portion of the reservoir during the rainy period. In general, the highest concentrations of chlorophyll, zooplankton density and biomass occurred in the Sapucaí River compartment, indicating its higher trophic condition as compared to the more oligotrophic River Grande compartment. Zooplankton biomass as a whole is low compared to other reservoirs, as expected for an oligotrophic system.
Capacidade para o trabalho, sintomas osteomusculares e qualidade de vida entre operadores de máquinas agrícolas
(Universidade Federal de São Carlos, 2011-02-11)
Milani, Daniela
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Monteiro, Maria Silvia
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https://lattes.cnpq.br/0451711594111248
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https://lattes.cnpq.br/1964869943124053
Introduction: Studies about work ability are relevant specially due to the population aging and the workforce aging in order to avoid early retirement. Those subjects whose employment has physical demands present more frequently injuries than others. The musculoskeletal disorders are the most common disorders among these injuries. These disorders have been important cause for work ability decrease among workers and may have negative impact in their quality of life. The agricultural sector activities include tasks with important physical demands. These tasks may have a negative impact in the workers health. However in Brazil, health-related aspects of these workers are unusual. Objectives: To evaluate the work ability and its association with musculoskeletal symptoms and quality of life aspects in agricultural machinery operators. Methodology: A cross-sectional study was carried out in an industry of the sugarcane sector in Brazil. The subjects (n=204) were agricultural machinery operator. They answered a questionnaire on demographics, work, lifestyle characteristics, Work Ability Index (WAI), The Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) and the Nordic Musculoskeletal Symptoms questionnaire. Results: The mean age of the workers was 32.3 years. The men comprised 99% of the study population and the average duration of work at the institution was 5.4 years. Physical activity was reported by 45.1%. Considering at least one body part, the musculoskeletal symptoms presence over the past 12 months was reported by 47.1% of the workers and the upper back symptoms were most frequents. The SF-36 dimensions presented scores above 79.3 points and a mean WAI score was 45.2 points. The statistical analysis showed that the work ability was associated with age, education and musculoskeletal symptoms. The wrists and hands symptoms were significantly associated with work ability. Those SF-36 dimensions that had most significant with work ability were role physical and bodily pain. Conclusion: Although in this study the workers had been young, important portion have already presented musculoskeletal symptoms and presented signs of work ability reduction. Furthermore, in this study, the musculoskeletal symptoms were significantly associated with WAI reduction and due to this; it is recommended that measures about promotion and improvement of the work ability and quality of life are deployed to base in musculoskeletal disorders prevention.
Efeito da fragmentação sobre a estrutura de populações de Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae) no sul do Brasil
(Universidade Federal de São Carlos, 2011-02-11)
Müller, Adelcio
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Matos, Dalva Maria da Silva
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https://lattes.cnpq.br/4728734263109138
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https://lattes.cnpq.br/5926860105977898
Fragmentation of habitat is the transformation of a continuous natural landscape into habitat patches or fragments, and may result from human settlements, agriculture, resource extraction and/or logging. Besides the influences of habitat loss, populations that remain in these fragments experience conditions similar to those of the surrounding matrix: the process known as "edge influence", one of the determinants which is the type of matrix surrounding the fragment. In the Southern region of Brazil is found the Mixed Ombrophylous Forest, also known as Araucaria Forest, and the species Araucaria angustifolia remains threatened by the use of its wood for domestic and commercial settings, as well conversion of its natural habitat into agropastoral activities and plantations of exotic species. The size distribution of the population carries a wealth of demographic information and often is the most unequivocal attribute available and accessible to a population. Therefore, the aim of this study was to obtain information on the population ecology of Araucaria angustifolia (Bertol.)O. Kuntze (Araucariaceae) on edges facing urban matrix, pasture matrix and agricultural matrix. In each of the five fragments were established 50 plots of 10m x 20m parallel to edge, with 25 deployed immediately at the edge and 25 at a distance of 120 meters from the edge. Within these plots, all individuals of Araucaria angustifolia were evaluated. There was no effect of edge on the structure of populations of Araucaria angustifolia evaluated for most variables, however; however, when we evaluated together matrix and shape of the fragments, we found a direct relationship with the density of individuals. The hypothesis that the population structure of Araucaria differs between the edge and inside regardless of shape, size or type of matrix has not been comproved, possibly because of the large variation in the population parameter between the fragments, independently of shape and matrix. But when these two characteristics were assessed together, they were significantly correlated with the total density of each fragment and its edge and interior.