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Confiabilidade do Transporte Público na Cidade de São Carlos
(Universidade Federal de São Carlos, 2018-07-13) Sasaya, Jimmy Tadashi; Hirosue, Fernando Hideki; https://lattes.cnpq.br/4091598921285700; https://lattes.cnpq.br/0464782881967064
In this work, the results of a diagnosis of the public transportation reliability in the city of São Carlos are discussed. To achieve these results, two methods for reliability evaluation were applied. The first method of evaluation consists in the comparison of the real time that the buses departed with the scheduled times, thus obtaining the percentage of the departures that are made during a threshold of reliability between a departure of no more than 3 minutes before and 5 minutes after the exact scheduled time. The second method of evaluation is composed of a qualitative survey of public transport users, in which it was evaluated concepts about the satisfaction in regard to punctuality and average time of delay or early departure that the general public experiences. It was concluded that the public transport reliability could be considered poor, with only 48% of the trips being considered punctual. The surveys corroborate with the data gathered, showing the users’ dissatisfaction in regard to the reliability. Also presented at the conclusion are some strategies to improve this question.
As mudanças nas leis florestais e a quantificação de serviços ecossistêmicos em microbacias rurais
(Universidade Federal de São Carlos, 2018-07-13) Rosário, Victor Alexandre Carlotti; Viani, Ricardo Augusto Gorne; https://lattes.cnpq.br/3250752369062840; https://lattes.cnpq.br/2572385052955529
The demand for information about resources quantity and quality of a watershed, and how these resources are related with riparian forests, restoration, farming and Ecosystem Services (ES) production, are very debated nowadays. Thus, the determination of factors that directly and indirectly affect the quality and quantity of these resources, and how it affects the landscape dynamic, must be studied for a better balance between agriculture and environment. The objective of this study is quantify the potential of ES production related to soil conservation and carbon stock in different forest restoration scenarios and the adoptions of soil conservation practices in agriculture areas. Two micro watersheds were studied: Posses (Extrema – MG) and Ribeirão Vermelho (São Pedro – SP). Three scenarios were considered: the current land use and soil cover, the old Forest Code (1965 – scenario I), and the Native Vegetation Protection Law (NVPL, 2012 – scenario II). The metrics used in this evaluation were soil loss, soil retention and sedimentation. Carbon stock was estimated for current forest cover, for restoration areas and for the others current land covers and uses. To evaluate the soil conservation and agricultural practices were simulated different scenarios with and without conservation practices and different riparian forest protection buffers. Regarding the current scenario, the NVPL will increase the forest cover, decrease sedimentation, soil loss and increase the carbon stock for the Posses and Ribeirão Vermelho micro watersheds. It was verified that the a bigger forest cover (scenario I), provides less soil loss and less sediment that reaches the waterways when compared to landscapes with lower amount of native vegetation (scenario II). Therefore, the NVPL will reduce the area to be restored, the potential of recovery of forest cover and the ES production related with soil conservation in the micro watersheds studied compared to what would be obtained with the old forest code. In addition, the conservation practices adoption, with and without, influenced soil loss and sedimentation more than the riparian vegetation buffers, evidencing the importance of the adoption of good agricultural practices within the concept of forest restoration and landscape.
Compatibilização química em compósitos de PLA reforçados com fibras de sisal
(Universidade Federal de São Carlos, 2018-07-13) Takahashi, Márcio Conti; Bettini, Sílvia Helena Prado; https://lattes.cnpq.br/3687551763124327; https://lattes.cnpq.br/4381321217525552
Even though poly(lactic acid) (PLA) is fragile under impact and has low toughness, the polymer stands out for its stiffness and high tensile strength. This polymer is an interesting material not only for short-term applications, such as disposable products, but is also suitable for durable goods. Although PLA is a potential substitute for conventional polymers, its use is limited by high costs. Incorporation of vegetal fibers in PLA matrix has been evaluated as a manner of costs reduction and, consequently, raise the economic competitiveness of the polymer. Poor interfacial adhesion has been observed as consequence of chemical incompatibility of the phases in the composites, resulting in unsatisfactory mechanical performance. Addition of PLA grafted with maleic anhydride, PLA-g-MA, is a possible alternative to improve interfacial adhesion. Aiming costs reduction and, simultaneously, enhance or, at least, maintain PLA’s high mechanical performance, this project investigated the effects of addiction of two types of compatibilizers, prepared by reactive extrusion, with different chemical characteristics: one of them with higher molar mass and lower acidity content and the other with lower molar mass and higher acidity content. Composites containing 10 and 30% wt of sisal fibers were prepared by extrusion. Two levels of compatibilizers mass content, 2 and 6%, were used in formulations. Results of size exclusion chromatography analysis revealed intense molar mass reduction of the matrixes during processing, in presence of sisal fibers. In contrast, the presence and content of compatibilizer had no significant influence on matrixes degradation. Nucleating effect of sisal fibers to PLA crystallization on composites was verified. Were attained increases of 90 and 120% on impact strength and Young modulus in composites, respectively. The objective of maintaining the tensile strength of PLA in the composites was achieved. Meanwhile, no gains were reached on the property, even in presence of compatibilizers.
Detecção de impactos em estruturas unidimensionais utilizando o método TDOA (Time Difference of Arrival)
(Universidade Federal de São Carlos, 2018-07-13) Garcia, Gabriella Faina; Shiki, Sidney Bruce; https://lattes.cnpq.br/0573973677787523; https://lattes.cnpq.br/2187363760175978
Impact is a dynamic load on a structure in which a high module force is applied within a short period of time. Then, as the impact has affected a steel beam, it is possible to analyze the mechanical signals measured produced by the piezoelectric sensors. Therefore, in this thesis, the Time Difference of Arrival (TDOA) method is used to detect the impact. It consists of utilizing two sensors placed within a known distance from each other, which have the objective of localizing the impact through measures of the wave transmitted along the beam by the dynamic load. The localization of the impact was done using the method in question and then compared to its actual position.
Dinâmica populacional em diferentes escalas espaciais de duas espécies arbóreas da Floresta Atlântica
(Universidade Federal de São Carlos, 2018-07-13) Rosa, Lucas Benedito Gonsales; Sampaio, Maurício Bonesso; https://lattes.cnpq.br/1062184411612711; Martins, Valéria Forni; https://lattes.cnpq.br/0686674300788674; https://lattes.cnpq.br/3446347336534069
The population dynamics of plants can be differently influenced by environmental differences in both regional and local scales. On a regional scale, population dynamics can be influenced by climate, stochastic events and anthropogenic actions. On a local scale, dynamics can also be influenced by environmental characteristics that differ locally, such as light, topography and soil characteristics. Environmental differences in both regional and local levels are expected to have a greater effect on specialist species, which present a more restricted geographical distribution and lower local abundance than generalist species. The objective of this study was to test the spatial variation in the dynamics of different populations of two tropical tree species, with extremely different geographic distributions and local abundances, and how they responded to environmental differences on a local scale. We used data from two demographic censuses of Faramea picinguabae M.Gomes (Rubiaceae) and Mollinedia schottiana (Spreng.) Perkins (Monimiaceae), which were performed approximately 9 years apart, held in two non-contiguous, permanent 1-ha plots (B and E) located at a region of the Atlantic Rainforest, Southeast Brazil. Due to the species’ geographical distribution and local abundance, we have assumed that F. picinguabae is a specialist species and M. schottiana is a generalist species. Each plot was divided into 100 subplots, in which we measured the canopy opening, elevation, declivity, and soil coverage by rocky boulders. In order to test the existence of spatial variation in the dynamics among plots, we have compared the environmental variables among plots, where the population is defined as the group of individuals of the same species in the same plot. In turn, to test how local environmental variations influence population dynamics, we have divided each of the environmental variables into categories and defined population as the group of individuals of the same species in each of the categories. In the two previous cases, we have calculated the limited rate of annual population growth (λ). We have found differences in annual λ both among plots and among categories of environmental variables only for the specialist species. All populations presented annual λ < 1, except for F. picinguabae on plot B and in environmental categories where the canopy openings are similar and higher than the average among censuses. The population decline of most populations may be explained by the intense drought in Ubatuba in the last decade. However, on a local scale, the population growth of F. picinguabae in plot B may have occurred due to a positive response of this species to the lower soil coverage by rocky boulders, which seems to have balanced the negative consequences of the drought. The understanding of how environmental variations, acting at different scales, influence the λ of plant populations with distinct strategies is important to help predict their behavior against environmental changes. From this, further studies are needed to determine how common this variation in population dynamics is and whether it can be predicted by species strategies, aiming at management actions to stabilize or increase their population size within a forest.
Análise da cobertura da rede de linhas do transporte coletivo urbano em São Carlos
(Universidade Federal de São Carlos, 2018-07-13) Souza Filho, Elias Martins de; Hirosue, Fernando Hideki; https://lattes.cnpq.br/4091598921285700; https://lattes.cnpq.br/5738854124740660
This research emphasizes the importance of public transportation on the life of users and on city operation. São Carlos’ network of public transport bus lines is the study object, and is run, at the moment, by Suzantur. Through the creation of a network line map of the city, it was possible to analyze the network functionality, disposure and, through the method of determining accessibility area bands around the lines as served areas, calculate the portion of municipal population served by it. The research showed results for São Carlos, and also the possibility of applying this method on other cities. Although existing some overlapping lines, what may decrease the transportation efficiency, the study showed a positive result, as it revealed, for the last few years, an increase on the analyzed system’s coverage, going to 97,40% of the municipal population having accessibility categorized as “good”, which means, at this case, all people inside an area of a 200 meter band around the lines.