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Detecção de novidade em fluxos contínuos de dados multirrótulo
(Universidade Federal de São Carlos, 2019-07-29) Costa Júnior, Joel David; Cerri, Ricardo; https://lattes.cnpq.br/6266519868438512; https://lattes.cnpq.br/5293958366030922
Multi-label Stream Classification (MLSC) aims at classifying streaming examples into multiple classes simultaneously. It is a very challenging task, since new classes may emerge (concept evolution), and known classes may change over the stream (concept drift. Most of classifier methods deal with the aforementioned characteristics updating their models when actuals labels of examples become available, it is a very optimistic scenario though, since for many data streams application these labels are never available, hence is unfeasible to update models in a supervised fashion. This is known as infinitely delayed labels problems and a task that has been stood out for dealing with it, is the Novelty Detection (ND). ND aims at detecting new patterns in arriving streaming examples that, in some aspect, might differ from the previously observed patterns and then used for updating the decision models. Despite different ND procedures have been proposed in the literature, it is still an open problem for MLSC. In this work we proposed two new methods: the MultI-label learNing Algorithm for data Streams with Label Combination-based methods (MINAS-LC) which applies ND to deal exclusively with concept drifts and the MultIlabel learNing Algorithm for data Streams with Binary Relevance transformation (MINAS-BR) which applies ND to deal with both concept drifts and concept evolution either. The methods address problem transformation techniques to deal with multi-labelled data at the offline phase and build micro-clusters based decision models. At the online phase the arrival examples are classified or rejected (labelled as unknown) by the current decision models. Rejected examples are used in ND phase to shape new micro-clusters, maintaining the decision models updated. The ND phase is run from time to time to work around concept drifts and concept evolution. Experiments over synthetic and real-world data sets with different degrees of concept drift and concept evolution attested the potential of MINAS-BR and MINAS-LC, in which have obtained significant results when compared to baseline methods.
Taxonomia, ecologia e distribuição espacial de rotifera no estado de São Paulo
(Universidade Federal de São Carlos, 2019-07-29) Ribeiro, Tainá Alves; Rocha, Odete; https://lattes.cnpq.br/7577441794992601; https://lattes.cnpq.br/5531769361645809
Rotifers inhabit a variety of aquatic habitats. It is thought that the success of this group is largely due to their small size, short life cycle, ang high richness of species, being these aspects largely responsible for the species richness of zooplankton communities in freshwater ecosystems. The aim of this study was to evaluate the taxonomic composition of rotifer communities in different types of freshwaters of São Paulo state, distributed in 22 Management unities of water resources (UGHRI). Zooplankton communities of 283 water bodies were sampled by horizontal net hauls. In situ measurements of pH, electrical conductivity, temperature and O2 concentrations were performed and water samples were simultaneously taken for laboratory measurements of chlorophyll a concentration. Based on chlorophyll concentration values, the trophic state index (TSI) was calculated and water bodies were then classified in one of six categories regarding their trophic degree. A total of 113 species of Rotifera, belonging to 20 different families were recorded. Families with highest species richness were Lecanidae, Brachionidae and Trichocercidae, following a pattern already described for tropical region rotifer communities. The species with highest frequency of occurrence were Lecane bulla, ocurring on 70% of all water bodies sampled and Lecane leontina, with 35,9%. There was a significant linear relationship between the number of water bodies sampled in each management unity and their rotifer species richness. It was also verified a low positive correlation, but statistically significant between species richness and the trophic state of the water bodies. There were evidences that the spatial distribution pattern observed for rotifers was influenced mainly by physical and chemical characteristics and trophic state of the water bodies. There are indicatives that differently from the pattern frequently observed for microorganisms, the distribution of most species can be restricted more by tolerance limits regarding environmental variables than by their dispersal capacity.
Princípios e fundamentos teóricos da catalogação descritiva e a proposta do Resource Description and Access (RDA)
(Universidade Federal de São Carlos, 2019-07-29) Machado, Raildo de Sousa; Zafalon, Zaira Regina; https://lattes.cnpq.br/1584935790390793; https://lattes.cnpq.br/9586215965015886
Cataloging codes are the subject of research, and Resource Description and Access (RDA) is their object of study. In the course of the research, it is questioned about the relation of the principles and fundamentals of cataloging with the proposal of the RDA. To this end, the general objective seeks to discuss the RDA proposal in the light of the principles and foundations of descriptive cataloging. The specific objectives have [1] map scientific discussions about the RDA; [2] analyze the founding theorists of cataloging, its principles and foundations; [3] present the history of cataloging codes and treaties; [4] present the basic conceptual models of contemporary cataloging; [5] analyze the RDA, its principles and objectives; [6] present the theoretical and practical movement from the publication of the RDA, which objectives will lead to understand the past, present and future of the RDA and how it appropriates the principles and foundations of descriptive cataloging. The applied research adopts a qualitative approach, making use of systematic literature mapping as part of the bibliographic and documentary procedures to achieve the exploratory and descriptive objectives. Academically, it is intended to contribute to discussions about the essence of the RDA, by expanding the possibilities of studies and familiarity with the objectives, principles, functions and application of the RDA standard. This research is justified in the context of Information Science because it is the organization and representation of information and, in the scientific contribution, brings trends on the subject as a result of the literature mapping.
Proposição de modelos de classificação e de calibração para polímeros presentes em resíduos eletrônicos empregando laser-induced breakdown spectroscopy (LIBS) e ferramentas quimiométricas
(Universidade Federal de São Carlos, 2019-07-29) Costa, Vinicius Camara; Pereira Filho, Edenir Rodrigues; https://lattes.cnpq.br/3394181280355442; https://lattes.cnpq.br/6162409795305177
This thesis proposes the development of analytical methods for the analysis of polymers from waste electrical electronic equipment (WEEE) by laser-Induced breakdown spectroscopy (LIBS). The results presented in the chapters 2 and 3 of this thesis were developed in collaboration with a recycling company of WEEE called REVERSA. In the first method proposed LIBS was used for the identification and classification of six polymers and a total of 477 samples were analyzed. Classification models using k-nearest neighbors (KNN) and soft independent modeling of class analogy (SIMCA) were used to classify the polymers. The proposed models presented satisfactory results for the validation samples, with accuracy of 98% for KNN and 92% for SIMCA. In addition, other validation parameters such as sensitivity, false alarm rate and specificity showed adequate. In the second method, the LIBS was employed to determination of the constituents polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) in PC/ABS blends. For this were built multivariate calibration models using partial least squares (PLS). The PLS models obtained for the PC and ABS presented good analytical parameters as: i) standard error calibration (SEC) of 3.4 (w/w%); (ii) standard error of cross-validation (SECV) of 5.6 (w/w%); iii) linear correlation coefficient of 0.996; iv) number of latent variables equal to 2; v) explained variance of 70%. For the validation of the PLS models PC/ABS blends with unknown concentrations of PC and ABS were analyzed, and the information provided by LIBS was in agreement with the reference technique. A third method was developed in collaboration with a plastics recycling company of car batteries. These plastics were contaminated with Pb and the objective was to evaluate different calibration strategies in LIBS for the quantitative determination of this analyte. Multivariate calibration strategies and a new univariate strategy were proposed. The new univariate calibration strategy was called a two-point calibration transfer and the results presented were satisfactory. The chemometrics tools including experimental desing, supervised methods for classification, unsupervised methods and multivariate calibration were employed during the development of the methods proposed in this thesis.