[pt] A crise atual pela qual passo mundo tornou-se a grande responsável pelo desenvolvimento científico-tecnológico, que se fará presente no próximo século. Dentre as diversas fontes alternativas, que se apresentam, a energia eólica tornou-se uma das mais destacadas, sobretudo devido ao uso de moinhos de vento (Cataventos). Os moinhos de vento são máquinas de fluxo que convertem a energia cinética dos ventos em outras formas de energia, fornecendo, portanto, substancias melhores ao dia-a-dia da humanidade. O trabalho que se apresenta trata do desenvolvimento teórico-experimental sobre o rotor de resistência, do tipo de eixo vertical, conhecido como rotor Savanius ou vulgarmente rotor S. Este tipo de rotor pode possuir as mais diversas formas geométricas para as pás. Entretanto, a mais divulgada, devido a sua facilidade de construção, é a semi-circunferencial, sobre a qual incidiu o desenvolvimento teórico deste trabalho. Um dos objetivos básicos do projeto da turbina eólica do tipo Savonius, é desenvolver tecnologia e obter experiência em operação de cata-ventos, em especial, visando o projeto e construção de unidades de grande porte. O desempenho do projeto do rotor é feito através de uma análise simplificada do modelo matemático. Por intermédio de valores experimentais, foram obtidas as curvas adimensionalisadas de torque (Ct) e de potência (Cp) versus a razão de velocidade (E), as quais podem servir para predizer o desempenho do rotor. Através deste procedimento, fez-se a análise para diversas formas geométricas de rotores. Finalmente comparando-se os resultados experimentais com a teoria desenvolvida, foram obtidas as curvas que relacionam o coeficiente de entrada (Ko) e a razão de velocidade(E). (Estas curvas foram obtidas somente, para o caso rotores de configuração de pás semi- circunferencial, que é o mais usual). / [en] The present crisis though which world passes now has become responsible for the scientific technological development that will take place in the next centrury. Among the various alternative aources in existence eolic energy has become one of the most outstanding, mainly by the use of the windmills (weathervane). Windimille are flow machines that convert wind kinetic energy into other of energy, whitch provide substancial goods to mankind. The present work deals wind kinetic energy into other of energy, which provide substancial goods to mankind. The present work deals with the theoretical-experimental development of the resistance rotor, of the vertical axle type, known as Savonius or commonly as S Rotor. One of the basic aims of the savonius type turbine is to develop techonology and to obtain experience in the operation of windmills, specially aiming at the desing and construction of large sinze unit ies. The analysis of performace of the rotor is made base on a simplified mathematical model. By means of experimental values, non admimensional curves of torque (Ct) and power (Cp), verusu speed rate (E) were obtained, and are usefull in predicting the rotor s performace. Through this procedure the analysis of various forms of geometryc rotors was performed. Finally, comparing the experimental results with the theory developed, curves of entry coeficient (Ko) related to the spedd rate ware obtarned for rotors of sami-circunferencial blades configuration only.

O objetivo deste trabalho foi estudar o efeito do confinamento em encontros de pilares de concreto com uma determinada resistência à compressão com lajes ou vigas de concreto de menor resistência. Com isso pretendeu-se desenvolver um melhor entendimento desse assunto, ainda pouco explorado, avaliar recomendações de algumas normas e, onde necessário e possível, sugerir uma solução alternativa. Foram ensaiados à compressão axial vinte e dois modelos reduzidos que representavam pilares de canto ou internos, incorporando parte da laje, e pilares isolados, cujos resultados foram comparados com recomendações de normas, ACI-318, CSA 23.3 e pesquisadores como, Gamble e Klinar, Ospina e Alexander, Bianchini e Silveira dos Santos. Na verdade, esta pesquisa é um prosseguimento daquela realizada por Silveira dos Santos. Complementando os estudos experimentais, modelos em elementos finitos possibilitaram a melhor compreensão desse efeito e ainda viabilizaram a comparação dos resultados experimentais com o critério de confinamento sugerido pelo CM CEB-FIP e pelo Eurocode EC2. Concluiu-se que apenas para pilares internos, cercados por laje em toda a volta, há um aumento de resistência do conjunto por efeito do confinamento do concreto da laje, devendo-se ainda respeitar certos limites. Para pilares de canto é necessária a utilização de algum elemento que compense a falta do concreto, como por exemplo, uma armadura transversal. / The goal of this paper is to study the effect of the confinement in connections of concrete columns having certain strength with lower strength concrete slabs or beams. It was intended to develop a better understanding of this subject, still little explored, to evaluate some code recommendations and, where necessary and possible, to suggest a alternative solution. Twenty-two specimens of reduced models were tested in compression representing corner or internal columns, incorporating part of the slabs, and isolated columns. These results were compared with recommendations of codes, ACI- 318, CSA 23,3 and researchers as, Gamble and Klinar, Ospina and Alexander, Bianchini and Silveira dos Santos. Indeed, this research is a continuation of that one carried through by Silveira dos Santos. Complementing the experimental studies, finite elements models made possible the best understanding of this effect and still they had made possible the comparison of the experimental results with the confinement criterion suggested for CM CEB-FIP and Eurocode EC2. It had concluded that only for internal columns, surrounded by slab, there is a strength increase of the specimen caused by confinement of the slab\'s concrete respecting certain limits. For corner columns it\'s necessary the utilization of some element that compensates the missing concrete, for example, a transversal reinforcement.

This study sought to understand the relationships among locus of control, parenting style, academic procrastination, and financial independence with a population of undergraduate students. A sample of 61 students (39 females, 21 males, 1 other) completed measures of demographics, locus of control, parenting style, and academic procrastination. Participants were recruited within the last two weeks of the semester. Therefore, the sample probably contained a higher percentage of procrastinators than the general population. There were no significant correlations across the total sample. There was a significant positive correlation between higher scores on the Parental Authority Questionnaire authoritative scale and the Procrastination Assessment Scale Student Frequency scores for individuals who were financially dependent. There was also a significant negative correlation between the authoritarian and authoritative parenting style scores for those who were financially dependent.

[pt] A utilização de estruturas espaciais metálicas como solução estrutural para cobertura de edificações no Brasil tem sido cada vez mais difundida.Esses sistemas são basicamente compostos pela união de barras através de nós de ligação, formando uma malha tridimensional de barras no espaço. A principal diferença existente entre os vários sistemas espaciais metálicos até hoje desenvolvidos corresponde principalmente aos diferentes tipos de nós de ligação adotados. A complexidade dos diferentes tipos de nós de ligação tem sido o principal fator diferencial de custo entre cada sistema. No Brasil, por motivos econômicos o tipo de nó de ligação mais utilizado é o de ponta amassada.O nó de ligação de ponta amassada é o mais simples e mais barato para ser fabricado, porém, possui duas desvantagens principais: este tipo de nó gera o aparecimento de excentricidades na aplicação dos esforços e provoca a redução de inércia nas extremidades das barras, devido ao processo de amassamento. As normas geralmente adotadas para o dimensionamento de estruturas espaciais metálicas [2, 11, 20] ainda não consideram adequadamente os efeitos da redução de inércia e das excentricidades. Tem sido cada vez mais freqüente a constatação de problemas de instabilidade estrutural em obras recentes, que podem causar colapsos parciais ou até mesmo totais. Estes fatos motivaram o estudo do comportamento estrutural dos nós de ligação com pontas amassadas, observando a influência da redução de inércia nas extremidades das barras e das excentricidades na resistência global das estruturas. Inicialmente apresenta-se um breve histórico dos sistemas estruturais espaciais metálicos, seguido de uma descrição dos principais nós de ligação existentes. A seguir são apresentadas informações gerais sobre a classificação dos diferentes tipos de treliças espaciais mais utilizados. Em seguida são descritos e apresentados três séries de ensaios, realizados em escala real, visando o estudo do comportamento estrutural e a avaliação de reforços estruturais com o objetivo de aumentar a capacidade de carga,diminuir os deslocamentos ou recuperar uma estrutura que apresente subdimensionamento.Finalmente os resultados são comparados com valores de projeto recomendados pelas normas de projeto de estruturas de aço. / [en] The use of spatial structures as a natural structural system for long spans is becoming more frequent in Brazil. These structural systems, basically composed of bars and nodes, enable the development of a very efficient tri- dimensional mesh. The main difference between the major spatial systems is associated with the adopted structural connections being the node complexity the main factor for the cost difference between each system.In Brazil, by economic reasons, the most adopted connections uses the end- flattened bar converging into the node connected with a single bolt. This type of joint is the simplest and cheaper to be manufactured, but it has two main disadvantages, the generated eccentricity force and the bar`s inertia reduction due to the flattening process.Nowadays the structural design codes still do not properly tackles the inertia reduction and eccentricities effects previously mentioned. On the other hand, structural instability problems that can cause local or even global collapses have being more frequently noticed in recently executed structures. This was the main motivation for the investigation of the structural behaviour of spatial structures with flattened edges connections.A brief history of spatial structural systems is initially presented, followed by a description of the more usual splice joints. This is followed by a general description of the spatial trusses use and classification. This work continues with a depiction of an experimental program, consisting of three series of full-scale tests was performed to enlighten the structural behaviour. This work also presents a study of the structural reinforcements; created to improve the structural load capacity, minimize deflections or recuperate structures under-designed. Finally the experimental results are compared with design codes provisions.

In resurgence, a target behavior (R1) is acquired in an initial phase and extinguished in a second phase while an alternative behavior (R2) is reinforced. When reinforcement for the second response is removed, however, R1 behavior returns or “resurges.” The resurgence paradigm may have implications for understanding relapse after behavioral interventions in humans such as contingency management, or CM, in which (for example) drug users can earn vouchers contingent upon drug abstinence. The present experiments examined the effectiveness of a putative retrieval cue for treatment in attenuating the resurgence effects and determined the likely mechanism by which this cue functions. Experiment 1 established that a 2-second cue associated with delivery of the alternative reinforcer in Phase 2 can attenuate R1 resurgence and promote R2 behavior during testing. Experiment 2 demonstrated that this effect occurs regardless of whether the cue is delivered contingently or noncontingently on responding during the resurgence test, and Experiment 3 demonstrated that for the cue to be effective in reducing resurgence, it must be paired with alternative reinforcement during Phase 2. This might mean that pairing the cue with reinforcement serves to maintain attention to the cue. Experiment 4 suggested that a cue paired with alternative reinforcement did not serve as a conditioned reinforcer in that making it contingent on a new behavior did not increase the likelihood of that behavior. Experiment 5 demonstrated that the cue must be experienced in sessions that also include the extinction of R1. Experiment 6 found that a cue produced by R1 during the second phase of a resurgence paradigm (analogous to a conditioned inhibitor) does not attenuate resurgence of an extinguished instrumental response. Together, the results suggest that a neutral cue can serve as an effective cue that attenuates resurgence if it is first paired with alternative reinforcement and presented in sessions in which R1 is extinguished. One way to view the results is that creating greater generalization between the extinction context and the testing context results in less resurgence.

In the animal laboratory, stressors can produce the relapse of drug-seeking behaviors after the behavior has been inhibited by extinction. This type of relapse has been called stress-induced reinstatement, and it models the relapse that is commonly reported in human populations. Interestingly, in the laboratory, stress does not typically reinstate extinguished behaviors that have been reinforced by food. One account of the discrepancy is that drugs of abuse may induce stress; therefore, when organisms learn to respond for drugs, they might learn to make the response in the “context” of stress. If so, then stress-induced reinstatement may be better described as renewal in a stress context. Renewal is the type of relapse that occurs when a behavior is returned to the original training context (or is shifted to a new context) after it has been inhibited or suppressed by extinction. Although renewal has usually been studied with contexts that differ in their exteroceptive cues, interoceptive cues (e.g., mood, food deprivation, and drug states) may also provide contexts. Accordingly, if an interoceptive stress state is present when food-seeking behavior is learned, then extinguished food seeking, like drug seeking, should also renew when the organism is stressed after extinction. In this dissertation, I discuss six experiments that investigated this hypothesis. Experiment 1 found that stressors renew extinguished food-seeking if they are also present during instrumental training. Experiments 2 and 3 then provided preliminary evidence that this effect is not exclusively due to incentive learning. Experiment 4 then suggested that interoceptive stress, and not the particular stressor that produces it, may indeed serve as a general interoceptive context that controls the effect. Experiment 5 found that stressors present for acquisition but not extinction training render behavior susceptible to stress induced relapse. The final experiment found that food-reinforced behavior learned in a context created by a cocaine injection renews after cocaine administration but not after footshock stress. Overall, the results indicate that the presence of interoceptive stress stimuli may play the role of context in a renewal paradigm and promote behavioral relapse when re-encountered after extinction. The implications for relapse that often occur following successful suppression of drug use and overeating behaviors are both discussed.

No description available.

No description available.

Identifying effective instructional modifications for English-language learners (ELL) experiencing reading problems is a difficult task given the vast individual differences in language proficiency, motivation, and school experience. To address this issue, this study investigated the utility of brief experimental analysis as a means to quickly identify the most effective instructional components to increase reading performance for five ELL. Using a multielement design, five treatments were administered one by one with increasing language support. There were individual differences in response and effective treatments were identified for all participants. Further, an extended analysis of alternating baseline conditions with the hypothesized effective treatment indicated that selected interventions increased reading rates for four participants over time. A combination of the two most effective interventions based on results from the brief experimental analysis increased reading performance for the fifth student. These procedures appear to hold promise for quickly identifying effective instructional components for individual ELL.

Some investigators have suggested that when material becomes more complex, an individual is forced to use an intuitive process, while others suggest that increasing complexity forces analysis. This study was an attempt to resolve this question by manipulating rate of presentation and instructions. No effect was found due to these manipulations or due to complexity. The reason is not clear, but may be due to a combination of factors which inclined the experiment in the direction of the intuitive process.