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Search Results: 1 - 10 of 538576 matches for " Lúcia Valéria R. de;Swiech "
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Um método evolucionário para sintonia de controladores PI/PID em processos multivariáveis
Arruda, Lúcia Valéria R. de;Swiech, Maria Cristina Szpak;Neves-Jr, Flávio;Delgado, Myriam Regattieri;
Sba: Controle & Automa??o Sociedade Brasileira de Automatica , 2008, DOI: 10.1590/S0103-17592008000100001
Abstract: nonlinear multiple-input multiple-output (mimo) processes which are common in industrial plants are characterized by significant interactions and nonlinearities among their variables. thus, the tuning of several controllers in complex industrial plants is a challenge for process engineers and operators. this paper addresses the problem of simultaneously tuning n proportional-integral-derivative (pi/pid) controllers in a coupled multivariable process as a multi-criteria optimization problem. a multi objective genetic algorithm modified by a niching technique with castes formation is proposed to solve this problem. the optimization is carried out in two levels. in the first level a local function that considers both the integral time squared error (itse) and the minimum variance criteria is computed to separately evaluate the performance of each closed loop. thereafter, a global cost function that considers all the loops is used to compute a set of solutions (a set of pi/pid parameters) to the optimization problem. the proposed system was applied to the control of a fluid catalytic cracking (fcc) unit, and its performance was compared to dynamic matrix control (dmc). the results show the applicability and effectiveness of the proposed method.
Phlebotomine sand flies and canine infection in areas of human visceral leishmaniasis, Cuiabá, Mato Grosso
Mestre, Gustavo Leandro da Cruz;Ribeiro, Ana Lúcia Maria;Miyazaki, Rosina Djunko;Rodrigues, Jorge Senatore Vargas;Almeida, Arleana do Bom Parto Ferreira de;Sousa, Valéria Régia Franco;Missawa, Nanci Akemi;
Revista Brasileira de Parasitologia Veterinária , 2011, DOI: 10.1590/S1984-29612011000300010
Abstract: visceral leishmaniasis is a systemic infectious disease that can cause to a severe, potentially life-threatening chronic condition in humans. risk factors for infection in urban areas have been associated with poor living conditions, the presence of sand fly vectors and infected pets. this study aimed to describe sand fly and canine infection in the neighborhoods of human visceral leishmaniasis occurrence in the city of cuiabá, mato grosso state, central-western brazil, reported between january 2005 and december 2006. a total of 1,909 sand flies were collected. they were predominantly males and the most frequent species were lutzomyia cruzi (81.25%), lutzomyia whitmani (13.88%) and lutzomyia longipalpis (2.62%). the sand fly density was not significantly correlated with the variation of environmental factors. the prevalence of canine visceral leishmaniasis in the neighborhoods studied was 26.82% and it was found that areas with high density of vectors coincided with areas of high prevalence of dogs and those with the highest rates of human cases. the study of vectors and other potential hosts are essential for a good understanding of visceral leishmaniasis and the related public health concerns, aiming at the prevention and control of leishmaniasis in the city of cuiabá, mato grosso state.
Psicólogo Escolar, Orientador Educacional e Assistente Pedagógico na escola: um trabalho em coopera??o?
Machado, Vera Lúcia Sobral;Xavier, Ana Paula M.;Papo, Guiomar R.;Wierman, Maria Letícia;Castaldelli, Valéria;Domingues, Valéria;
Paidéia (Ribeir?o Preto) , 1993, DOI: 10.1590/S0103-863X1993000100006
Abstract: the figure of the school psychologist is becoming more conspicuous on the brazilian educacional scene. the demand for the services of these professionals by different teaching institutions has been increasing, and so have union and council movements aiming at the coordination of discussions on the role of school psychologist and concentrating efforts to have city and state schools hire these professionals. in view of these considerations, it is interesting to investigate to what extent this new professional position in is conflit with existing ones, especially that of educacional advisor. indeed, even though theoretically the attributions of each professional are defined, in practice a confusion of roles has been observed due to the difficulty in delimiting the area of action of each. thus, the objective of the present study was to determine the extent of this difficulty and whether it creates conflict or cooperation in terms of work performance. the first step was a survey of state, city and private schools registered with the regional department of education of ribeir?o preto and counting with the services of these professionals. schools where one or more of these professionals were present were visited and interviews were carried out. the data obtained were processed in terms of contexts of the interview and the following points were analyzed: professional training, emphasizing the relationship between tins training and the present performance, and the problems concerning the latter; difficulties and limitations perceived by the professionals in terms of performance; expectations concerning professional work existing in the situation in relation to the absence of the other professional; exchange between professionals in situations where they work together.
Um modelo híbrido (CLP-MILP) para scheduling de opera??es em polidutos
Magat?o, Leandro;Arruda, Lúcia Valéria Ramos de;Neves-Jr, Flávio;
Pesquisa Operacional , 2008, DOI: 10.1590/S0101-74382008000300007
Abstract: this work is motivated by the need of optimization in the pipeline-oil distribution scenario. the considered problem involves the short-term scheduling of activities in a specific pipeline. the pipeline is 93.5 km in length, and it connects refinery and harbor tankfarms, conveying different types of commodities (gasoline, diesel, kerosene, etc). an optimization model was developed to determine the pipeline scheduling with improved efficiency. such model combines constraint logic programming (clp) and mixed integer linear programming (milp) in an integrated clp-milp framework. the proposed model uses decomposition strategies, continuous time representation, and intervals that represent time constraints (time windows). real cases were solved in a reduced computational time (order of seconds). the computational results have demonstrated that the model is able to define new operational points to the pipeline, providing significant cost saving. indeed the clp-milp model is an efficient tool to aid the operational decision-making within this real-world pipeline scenario.
A multiagent simulator for supporting logistic decisions of unloading petroleum ships in habors
Brito, Robison Cris;Tacla, Cesar Augusto;Arruda, Lúcia Valéria Ramos de;
Pesquisa Operacional , 2010, DOI: 10.1590/S0101-74382010000300012
Abstract: this work presents and evaluates the performance of a simulation model based on multiagent system technology in order to support logistic decisions in a harbor from oil supply chain. the main decisions are concerned to pier allocation, oil discharge, storage tanks management and refinery supply by a pipeline. the real elements as ships, piers, pipelines, and refineries are modeled as agents, and they negotiate by auctions to move oil in this system. the simulation results are compared with results obtained with an optimization mathematical model based on mixed integer linear programming (milp). both models are able to find optimal solutions or close to the optimal solution depending on the problem size. in problems with several elements, the multiagent model can find solutions in seconds, while the milp model presents very high computational time to find the optimal solution. in some situations, the milp model results in out of memory error. test scenarios demonstrate the usefulness of the multiagent based simulator in supporting decision taken concerning the logistic in harbors.
Biometria de frutos e sementes e germina??o de Plathymenia reticulata benth. e Plathymenia foliolosa benth. (Fabaceae - mimosoideae)
Lopes, Renata de Melo Ferreira;Freitas, Valéria Lúcia de Oliveira;Lemos Filho, José Pires de;
Revista árvore , 2010, DOI: 10.1590/S0100-67622010000500005
Abstract: this study aimed to compare the biometry of fruits and seeds, as well as the effect of different scarification, temperature and light conditions on the germination of plathymenia reticulata benth. and plathymenia foliolosa benth. we measured the length, width, thickness, and fresh mass of fruits (n= 100) and seeds (n= 100) of each specie. the different treatments were mechanic and acid scarification, temperatures (photoperiod/nictoperiod) of 20, 30 and 35/15 °c (12/12 and 0/24) and 25 and 35 °c (12/12). p. foliolosa fruits were wider, thickener and heavier. its seeds are longer and thicker than those of p. reticulata. seeds of both species were not photosensitive. acid scarification did not increase significantly the percentage of seed germination of both species, but mechanic scarification increased significantly the percentage of seed germination for p. foliolosa. the percentage of germination at 25 °c of intact seeds of p. reticulata, scarified with acid and with sandpaper was, respectively, 55%, 60% and 89%. for seeds of p. foliolosa values obtained were, respectively, 48%, 37.5% and 83%. these results indicate limitations of germination of p. foliolosa imposed by the tegument but the effect of tegument restringing the germination of intact seeds decrease with the increase of temperature.
Um modelo de otimiza??o da opera??o de terminais petrolíferos usando a teoria das restri??es como pré-processamento
Boschetto, Suelen Neves;Lüders, Ricardo;Neves Jr., Flávio;Arruda, Lúcia Valéria Ramos de;
Pesquisa Operacional , 2009, DOI: 10.1590/S0101-74382009000100001
Abstract: in the scheduling of oil transfer operations for harbor plants containing ships, piers, tanks and pipelines, an optimization model is frequently used. however, due to the complexity involved, computational time is a real concern. in this paper, a mixed integer linear programming model (milp) found in the literature is studied and a preprocessing procedure is proposed. this procedure is based on the theory of constraints (toc), which is used to reduce the model compilation time. since the problem bottleneck is identified, the corresponding constraints are not considered in the preprocessing step. an analysis based on lp dual price is also carried out to verify actions taken in the preprocessing step. although optimality cannot be assured, the results obtained show a minor deviation from the optimal solution but with a significant computational time gain.
Algas marinhas bent?nicas da Reserva Biológica Estadual da Praia do Sul, Ilha Grande, Angra dos Reis, Rio de Janeiro, Brasil
Gestinari, Lísia M?nica de Souza;Nassar, Cristina Aparecida Gomes;Arantes, Patrícia Valéria dos Santos;
Acta Botanica Brasilica , 1998, DOI: 10.1590/S0102-33061998000100005
Abstract: a survey in the reserve showed 27 species of chlorophyceae, 21 of phaeophyceae and 73 of rhodophyceae. among the recorded species, 38 are new references to the island and cladophora catenata (l.) kütz. is for the first time quoted to the rio de janeiro coast. neither endemic species nor specific flora from insular area were found in the reserve. a comparison between the flora of the reserve and those of neighboring areas, showed a high percentage of similarity.
Levantamento de pesquisas sobre cultura escolar no Brasil
Knoblauch, Adriane;Ratto, Ana Lúcia Silva;Oliveira, Luciane Paiva Alves de;Ferreira, Valéria Milena Rohrich;
Educa??o e Pesquisa , 2012, DOI: 10.1590/S1517-97022012005000015
Abstract: this research attempted to examine the way the notion of school culture has been appropriated by investigations that take the brazilian schools as their object of study, especially those concerning research on elementary and intermediate schooling. it started with a survey of the students' production in graduate programs between 1987 and 2007, as found in the theses bank of capes. after that, 361 abstracts from dissertations and theses were selected as they referred the term school culture. next, an instrument was developed to examine the variables that could express the characteristics of such production. the analysis of twenty years of academic production indicates a tendency that studies on school culture has been on the rise along the years, as well as a concentration of such investigations in the south-southeast axis of brazil. in addition, dispersion was found in the supervision of researches, as there some effort of concentration just in a few programs or a few supervisors. another finding concerns the high representativeness of studies related to elementary and intermediate schooling, mainly those dealing with teacher education and training, school organization by means of cycles, school management, educational policy, curriculum and teaching methodologies. finally, one may conclude that the notion of school culture has been meaningful to understand the elementary and intermediate schooling.
Perfil das habilidades cognitivas no envelhecimento normal
Souza, Valéria Lopes de;Borges, Mirian Fernanda;Vitória, Cássia Maria da Silva;Chiappetta, Ana Lúcia de Magalh?es Leal;
Revista CEFAC , 2010, DOI: 10.1590/S1516-18462009005000056
Abstract: purpose: to analyze the cognitive functions in elderly during normal aging and check if variables such as sex, age and education interfere in the profile of those abilities. methods: a prospective, traverse and observational study was accomplished with a sample constituted by 50 institutionalized elderly without neurological compromising and memory-related complaint, with age varying from 65 to 89 years and having an education grade varying from 0 to 15 years. the test used in this study was the consortium to establish a registry for alzheimer's disease (cerad). results: the feminine gender obtained significant difference in the memory, recall and recognition tests. the age group: 65 - 75 years, obtained significant difference in the recall tests. the range of education from 8 to 15 years obtained significant difference in the boston tests and in the fluency test. conclusion: women had a better performance in the tests that involved memory. the elderly considered youths were better in the proof of memory related to recall. the individuals that had a better instruction grade obtained a better performance in the abilities that involved language.
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