938 resultados para Three-phase four-wire


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Pós-graduação em Engenharia Elétrica - FEIS

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This paper addresses the three-phase induction motor by a thermal analysis of its operation, under the gaze of the standards of the Brazilian Association of Technical Standards that deal with working arrangements (operating cycles) defined by appropriate tests and for each use of the motor basis of this study, emphasizing especially the fact of the first three cycles are the cycles with greater possibilities of use for scaling a three-phase induction motor for the main industrial processes, will also be made an analysis of the reasons why the three-phase induction motors have a loss of power at altitudes above 1000 m above sea level and some methods of how to define how a three phase induction motor can be used in one of the first three working arrangements

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Considering that the Brazilian energy source is based on hydroelectric power plants, every moment that it does not rain enough, we are likely to suffer power outage. Making the rational use of energy not only is wise, but also important for financial issues. The industrial sector is of great importance to Brazilian economic context, because it is one that creates more wealth and jobs. It should be noted that it is one of the sectors that consume more electricity. One of the most used equipment in industry is the three phase induction motor, which ends up providing significant waste of energy. For that reasons, studying three phase induction motors is important. One of the ways to evaluate the parameter of the three phase induction motor is using a dynamometer mechanic or electric. This work aims at further studies (and development) of electrodynamometer brake, a type of electrical dynamometer, that is the only one with reversible use. This means, it is possible to measure both the torque and the power transmitted by the electric motors, by the direct method and the indirect. Besides it allows greater stability in the imposition of charges, due to its nature of being able to regenerate the energy imparted by the engines being tested

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The goal for this communication is the speech development in children three to four years, and how games and child's plays can help them in the process. For this, we have set three specific goals. They are: select games and activities that serve as a means of furthering the development of speech; elect three activities, making sure at what point is the extra step to the outbreak of the sign/symbol and identify at what time of play the child uses more talk and no change in psychological structure. These games have been applied to children from three to four years in order to identify and record their actions and speeches during activities. Acquiring the ability to speak, the kids will be able to communicate socially and develop new forms of behavior. From young children already expresses themselves through babbling and even crying, because do not have a conventional language yet. From the social relationship, the child tends to become familiar with the language, and gradually learn how to use it, expressing her feelings and desires. When the development of language and thought intersect, transform the course of action of the child who begins to have control of your action. Such its importance in society, the language became the basis of childhood education and is the duty of teachers and educators to appropriate the necessary encouragement to the child to develop or improve her language

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This paper addresses the three-phase induction motor by a thermal analysis of its operation, under the gaze of the standards of the Brazilian Association of Technical Standards that deal with working arrangements (operating cycles) defined by appropriate tests and for each use of the motor basis of this study, emphasizing especially the fact of the first three cycles are the cycles with greater possibilities of use for scaling a three-phase induction motor for the main industrial processes, will also be made an analysis of the reasons why the three-phase induction motors have a loss of power at altitudes above 1000 m above sea level and some methods of how to define how a three phase induction motor can be used in one of the first three working arrangements

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Considering that the Brazilian energy source is based on hydroelectric power plants, every moment that it does not rain enough, we are likely to suffer power outage. Making the rational use of energy not only is wise, but also important for financial issues. The industrial sector is of great importance to Brazilian economic context, because it is one that creates more wealth and jobs. It should be noted that it is one of the sectors that consume more electricity. One of the most used equipment in industry is the three phase induction motor, which ends up providing significant waste of energy. For that reasons, studying three phase induction motors is important. One of the ways to evaluate the parameter of the three phase induction motor is using a dynamometer mechanic or electric. This work aims at further studies (and development) of electrodynamometer brake, a type of electrical dynamometer, that is the only one with reversible use. This means, it is possible to measure both the torque and the power transmitted by the electric motors, by the direct method and the indirect. Besides it allows greater stability in the imposition of charges, due to its nature of being able to regenerate the energy imparted by the engines being tested

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The goal for this communication is the speech development in children three to four years, and how games and child's plays can help them in the process. For this, we have set three specific goals. They are: select games and activities that serve as a means of furthering the development of speech; elect three activities, making sure at what point is the extra step to the outbreak of the sign/symbol and identify at what time of play the child uses more talk and no change in psychological structure. These games have been applied to children from three to four years in order to identify and record their actions and speeches during activities. Acquiring the ability to speak, the kids will be able to communicate socially and develop new forms of behavior. From young children already expresses themselves through babbling and even crying, because do not have a conventional language yet. From the social relationship, the child tends to become familiar with the language, and gradually learn how to use it, expressing her feelings and desires. When the development of language and thought intersect, transform the course of action of the child who begins to have control of your action. Such its importance in society, the language became the basis of childhood education and is the duty of teachers and educators to appropriate the necessary encouragement to the child to develop or improve her language

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The relative growth and population structure of the terebellid Nicolea uspiana were investigated in the intertidal zone of a rocky shore on the south-east coast of Brazil, from May 2006 to May 2007. Eight hundred and forty-seven individuals of N. uspiana were analysed: 391 males, 163 females, and 293 immatures. Although significant differences in some morphometric parameters were found, there was no sexual dimorphism between males and females. There were differences in total length, width of segments, and length of the notopodial region between matures and immatures. The negative allometry of the total length in relation to five other parameters showed that this feature is a good measure for estimating the individual size, which was then used in the analysis of population structure. This population of N. uspiana showed a bimodal size frequency distribution, with immature and mature individuals found during the entire year. This pattern indicates continuous reproduction, with each cohort growing for at least three to four months and being responsible for two consecutive settlement peaks.

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The present study reports on a survey of the gelatinous zooplankton fauna (Cnidaria, Ctenophora and Thaliacea) from the proposed Baia da Babitonga marine protected area (southern Brazil; similar to 26 degrees S), based on collections from multiple sites over different seasons and from published literature. In order to sample both small and large gelatinous animals, plankton hauls (n = 255) and fishing trawls (n = 126) were employed. More than 20,000 organisms were studied, which, including literature data, totaled 48 species: one cubomedusa, three scyphomedusae, four siphonophores, 36 hydromedusae, two ctenophores, and two thaliaceans. Among these, the hydromedusae Cnidostoma fallax Vanhoffen and Helgicirrha sp. are recorded for the first time from the southwestern Atlantic coast and Paulinum sp. and Protiara sp. are recorded for the first time from the South Atlantic. A description of young stages of the hydromedusa Gossea brachymera Bigelow is presented and shows that Octobulbacea montehermosensis Zamponi is a junior synonym of the former. Although comprehensive local assessment of diverse taxonomic groups is still lacking, the high diversity observed herein underscores the importance of Ba a da Babitonga as a high priority site for conservation of regional marine biodiversity.

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In this study, we analyzed the ABCD1 gene in X-linked adrenoleukodystrophy (X-ALD) patients and relatives from 38 unrelated families from South America, as well as phenotypic proportions, survival estimates, and the potential effect of geographical origin in clinical characteristics. Methods: X-ALD patients from Brazil, Argentina and Uruguay were invited to participate in molecular studies to determine their genetic status, characterize the mutations and improve the genetic counseling of their families. All samples were screened by SSCP analysis of PCR fragments, followed by automated DNA sequencing to establish the specific mutation in each family. Age at onset and at death, male phenotypes, genetic status of women, and the effect of family and of latitude of origin were also studied. Results: We identified thirty-six different mutations (twelve novel). This population had an important allelic heterogeneity, as only p. Arg518Gln was repeatedly found (three families). Four cases carried de novo mutations. Intra-familiar phenotype variability was observed in all families. Out of 87 affected males identified, 65% had the cerebral phenotype (CALD). The mean (95% CI) ages at onset and at death of the CALD were 10.9 (9.1-12.7) and 24.7 (19.8-29.6) years. No association was found between phenotypic manifestations and latitude of origin. One index-case was a girl with CALD who carried an ABCD1 mutation, and had completely skewed X inactivation. Conclusions: This study extends the spectrum of mutations in X-ALD, confirms the high rates of de novo mutations and the absence of common mutations, and suggests a possible high frequency of cerebral forms in our population.

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Diabrotica speciosa (Germar) is an economically important pest of Neotropical cultures and represents a quarantine risk for Neartic and Paleartic Regions. Despite its agricultural importance, few studies have been done on mating behavior and chemical communication, which has delayed the development of behavioral techniques for population management, such as the use of pheromone traps. In this study, we determined 1) the age at first mating; 2) diel rhythm of matings; 3) number of matings over 7 d; 4) the sequence of D. speciosa activities during premating, mating, and postmating; 5) the duration of each activity; and 6) response to male and female conspecific volatiles in Y-tube olfactometer. The first mating occurred between the third and seventh day after adult emergence and the majority of pairs mated on the fourth day after emergence. Pairs of D. speciosa showed a daily rhythm of mating with greater sexual activity between the end of the photophase and the first half of the scotophase. During the 7 d of observation, most pairs mated only once, although 30% mated two, three, or four times. In a Y-tube olfactometer, males were attracted by virgin females as well as by the volatile compounds emitted by females. Neither males nor their volatiles were attractive to either sex. Our observation provide information about mating behavior of D. speciosa, which will be useful in future research in chemical communication, such as identification of the pheromone and development of management techniques for this species using pheromone traps.

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Purpose. The primary objective of this study was to investigate the incidence of drug-drug interactions (DDIs) related to adverse drug reactions (ADRs) in elderly outpatients who attended public primary healthcare units in a southeastern region of Brazil. The secondary objective was to investigate the possible predictors of DDI-related ADRs. Methods. A prospective cohort study was conducted between November 1, 2010, and November 31, 2011, in the primary public healthcare system in the Ourinhos micro-region in Brazil. Patients who were at least 60 years old, with at least one potential DDI, were eligible for inclusion in the study. Eligible patients were assessed by clinical pharmacists for DDI-related ADRs for 4 months. The causality of DDI-related ADRs was assessed independently by four clinicians using three decisional algorithms. The incidence of DDI-related ADRs during the study period was calculated. Logistic regression analysis was used to study DDI-related ADR predictors. Results. A total of 433 patients completed the study. The incidence of DDI-related ADRs was 6.5%. A multivariate analysis indicated that the adjusted odds ratios (ORs) rose from 0.91 (95% confidence interval [CI] = 0.75-1.12, p = 0.06) in patients aged 65-69 years to 4.40 (95% CI = 3.00-6.12, p < 0.01) in patients aged 80 years or older. Patients who presented two to three diagnosed diseases presented lower adjusted ORs (OR = 0.93 [95% CI = 0.68-1.18, p = 0.08]) than patients who presented six or more diseases (OR = 1.12 [95% CI = 1.02-2.01, p < 0.01]). Elderly patients who took five or more drugs had a significantly higher risk of DDI-related ADRs (OR = 2.72 [95% CI = 1.92-3.12, p < 0.01]) than patients who took three to four drugs (OR = 0.93 [95% CI = 0.74-1.11, p = 0.06]). No significant difference was found with regard to sex (OR = 1.08 [95% CI 0.48-2.02, p = 0.44]). Conclusion. The incidence of DDI-related ADRs in elderly outpatients was significant, and most of the events presented important clinical consequences. Because clinicians still have difficulty managing this problem, highlighting the factors that increase the risk of DDI-related ADRs is essential. Polypharmacy was found to be a significant predictor of DDI-related ADRs in our sample.

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Introduction: Primary HIV infection is usually caused by R5 viruses, and there is an association between the emergence of CCXR4-utilizing strains and faster disease progression. We characterized HIV-1 from a cohort of recently infected individuals in Brazil, predicted the virus's co-receptor use based on the env genotype and attempted to correlate virus profiles with disease progression. Methods: A total of 72 recently infected HIV patients were recruited based on the Serologic Testing Algorithm for Recent HIV Seroconversion and were followed every three to four months for up to 78 weeks. The HIV-1 V3 region was characterized by sequencing nine to twelve weeks after enrollment. Disease progression was characterized by CD4+ T-cell count decline to levels consistently below 350 cells/mu L. Results: Twelve out of 72 individuals (17%) were predicted to harbor CXCR4-utilizing strains; a baseline CD4,350 was more frequent among these individuals (p = 0.03). Fifty-seven individuals that were predicted to have CCR5-utilizing viruses and 10 individuals having CXCR4-utilizing strains presented with baseline CD4.350; after 78 weeks, 33 individuals with CCR5 strains and one individual with CXCR4 strains had CD4.350 (p = 0.001). There was no association between CD4 decline and demographic characteristics or HIV-1 subtype. Conclusions: Our findings confirm the presence of strains with higher in vitro pathogenicity during early HIV infection, suggesting that even among recently infected individuals, rapid progression may be a consequence of the early emergence of CXCR4-utilizing strains. Characterizing the HIV-1 V3 region by sequencing may be useful in predicting disease progression and guiding treatment initiation decisions.