957 resultados para grammatical difficulties
Resumo:
Social behaviour is mainly based on swarm colonies, in which each individual shares its knowledge about the environment with other individuals to get optimal solutions. Such co-operative model differs from competitive models in the way that individuals die and are born by combining information of alive ones. This paper presents the particle swarm optimization with differential evolution algorithm in order to train a neural network instead the classic back propagation algorithm. The performance of a neural network for particular problems is critically dependant on the choice of the processing elements, the net architecture and the learning algorithm. This work is focused in the development of methods for the evolutionary design of artificial neural networks. This paper focuses in optimizing the topology and structure of connectivity for these networks.
Resumo:
Most of the patients that reside in the intensive care unit experience fear, frustration and high levels of anxiety as they are not able to communicate properly. In this sense, the use of communication tools can be helpful to reduce the frustration levels and also, to improve the efficiency and the speed of the communication. The objective of this work, is to design a tool that allows solving the communication problems that patients suffer when they are admitted in the intensive care unit. In order to achieve the objective of this work, a qualitative study that involved interviews with former patients, hospital staff members and family relatives was performed. Afterwards, the design of a prototype was developed to later conduct and analyze usability evaluations with former patients, hospital staff members and patients relatives. The results expose that participants of the usability evaluations were able to perform most of the tasks effectively.
Resumo:
The difficulties perceived in the orientation-based unified scheme models, when confronted with the observational data, are pointed out. It is shown that in meter-wavelength selected samples, which presumably are largely free of an orientation bias, the observed numbers of quasars versus radio galaxies are not in accordance with the expectations of the unified scheme models. The observed number ratios seem to depend heavily on the redshift, fluxdensity, or radio luminosity levels of the selected sample. This cannot be explained within the simple orientation-based unified scheme with a fixed average value of the half-opening angle (c approximately 45 degrees ) for the obscuring torus that supposedly surrounds the nuclear optical continuum and the broad-line regions. Further, the large differences seen between radio galaxies and quasars in their size distributions in the luminosity-redshift plane could not be accommodated even if I were to postulate some suitable cosmological evolution of the opening angle of the torus. Some further implications of these observational results for the recently proposed modified versions of the unified scheme model are pointed out.
Resumo:
Virtual Worlds Generator is a grammatical model that is proposed to define virtual worlds. It integrates the diversity of sensors and interaction devices, multimodality and a virtual simulation system. Its grammar allows the definition and abstraction in symbols strings of the scenes of the virtual world, independently of the hardware that is used to represent the world or to interact with it. A case study is presented to explain how to use the proposed model to formalize a robot navigation system with multimodal perception and a hybrid control scheme of the robot.
Resumo:
Virtual Worlds Generator is a grammatical model that is proposed to define virtual worlds. It integrates the diversity of sensors and interaction devices, multimodality and a virtual simulation system. Its grammar allows the definition and abstraction in symbols strings of the scenes of the virtual world, independently of the hardware that is used to represent the world or to interact with it. A case study is presented to explain how to use the proposed model to formalize a robot navigation system with multimodal perception and a hybrid control scheme of the robot. The result is an instance of the model grammar that implements the robotic system and is independent of the sensing devices used for perception and interaction. As a conclusion the Virtual Worlds Generator adds value in the simulation of virtual worlds since the definition can be done formally and independently of the peculiarities of the supporting devices.
Resumo:
Background: The Strengths and Difficulties Questionnaire (SDQ) is a tool to measure the risk for mental disorders in children. The aim of this study is to describe the diagnostic efficiency and internal structure of the SDQ in the sample of children studied in the Spanish National Health Survey 2006. Methods: A representative sample of 6,773 children aged 4 to 15 years was studied. The data were obtained using the Minors Questionnaire in the Spanish National Health Survey 2006. The ROC curve was constructed and calculations made of the area under the curve, sensitivity, specificity and the Youden J indices. The factorial structure was studied using models of exploratory factorial analysis (EFA) and confirmatory factorial analysis (CFA). Results: The prevalence of behavioural disorders varied between 0.47% and 1.18% according to the requisites of the diagnostic definition. The area under the ROC curve varied from 0.84 to 0.91 according to the diagnosis. Factor models were cross-validated by means of two different random subsamples for EFA and CFA. An EFA suggested a three correlated factor model. CFA confirmed this model. A five-factor model according to EFA and the theoretical five-factor model described in the bibliography were also confirmed. The reliabilities of the factors of the different models were acceptable (>0.70, except for one factor with reliability 0.62). Conclusions: The diagnostic behaviour of the SDQ in the Spanish population is within the working limits described in other countries. According to the results obtained in this study, the diagnostic efficiency of the questionnaire is adequate to identify probable cases of psychiatric disorders in low prevalence populations. Regarding the factorial structure we found that both the five and the three factor models fit the data with acceptable goodness of fit indexes, the latter including an externalization and internalization dimension and perhaps a meaningful positive social dimension. Accordingly, we recommend studying whether these differences depend on sociocultural factors or are, in fact, due to methodological questions.
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Despite the centrality of the difficulty concept in the study of disability, there has been little research on its significance from the point of view of people with functional limitations. The main objective of this study was to describe what older people understand when asked about difficulty in undertaking mobility activities. As a secondary objective, we considered whether there are any differences depending on the type of activities, according to the International Classification of Functioning (ICF) mobility domains. Methods: Seventeen community-dwelling men and women aged 70 years old or over were interviewed by means of a questionnaire containing 55 items covering the ICF mobility domains. The participants responded to the items while thinking aloud, saying what led them to give a specific answer about their level of difficulty. Inductive content analysis was conducted and categories, subthemes and themes were identified. Results: Causes of difficulty (pathologies, impairments, symptoms) and accommodations (task modifications and use of aids) were the two themes identified; and their importance (and that of the subthemes included) varied across the types of activity. All the participants said that they had no difficulty in at least one task, despite mentioning changes in the way they performed them. Conclusions: Older people's opinions were consistent with theoretical models of disability and with the standard practice of measuring functional limitations by asking about the degree of difficulty; however, the design of these measures needs to be improved in order to detect perceptions of no difficulty in the presence of task modification.
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The potential of integrating multiagent systems and virtual environments has not been exploited to its whole extent. This paper proposes a model based on grammars, called Minerva, to construct complex virtual environments that integrate the features of agents. A virtual world is described as a set of dynamic and static elements. The static part is represented by a sequence of primitives and transformations and the dynamic elements by a series of agents. Agent activation and communication is achieved using events, created by the so-called event generators. The grammar defines a descriptive language with a simple syntax and a semantics, defined by functions. The semantics functions allow the scene to be displayed in a graphics device, and the description of the activities of the agents, including artificial intelligence algorithms and reactions to physical phenomena. To illustrate the use of Minerva, a practical example is presented: a simple robot simulator that considers the basic features of a typical robot. The result is a functional simple simulator. Minerva is a reusable, integral, and generic system, which can be easily scaled, adapted, and improved. The description of the virtual scene is independent from its representation and the elements that it interacts with.
Resumo:
The aim of this study was to analyze reliability and validity evidence of scores on the Colombian version of the Questionnaire about Interpersonal Difficulties for Adolescents (QIDA) in a sample of 1,628 adolescents (65.7% boys), ranging in age from 12 to 18 years. Confirmatory factor analyses replicated the correlated five-factor structure of the QIDA: Assertiveness, Heterosexual Relationships, Public Speaking, Family Relationships, and Close Friendships. Internal consistency for the QIDA and subscales scores was excellent. Girls reported higher level of perceived anxiety in heterosexual relationships, whereas boys showed more anxiety in close friendships and decreased interpersonal anxiety during adolescence. Results support the reliability and validity of the scores on the Colombian version of the QIDA.
Resumo:
This study examined the reliability and validity evidence drawn from the scores of the French version of the Questionnaire about Interpersonal Difficulties for Adolescents (QIDA) in a sample of 957 adolescents (48.5% boys) ranging in age from 11 to 18 years (M = 14.48, SD = 1.85). A principal axis factoring (PAF) and confirmatory factor analyses (CFA) were performed to determine the fit of the factor structure of scores on the QIDA. PAF and CFA replicated the previously identified correlated five-factor structure of the QIDA: Assertiveness, Heterosexual Relationships, Public Speaking, Family Relationships, and Close Friendships. The QIDA yielded acceptable reliability scores for French adolescents. Validity evidence of QIDA was also established through correlations with scores on the School Anxiety Inventory and the Social Anxiety Scale for Adolescents. Most of the correlations were positive and exceeded the established criteria of statistical significance, but the magnitude of these varied according to the scales of the QIDA. Results supported the reliability and validity evidence drawn from the scores of the French version of the QIDA.
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Our study sets out to identify the difficulties that high school students, teachers, and university students encounter when trying to explain atomic spectra. To do so, we identify the key concepts that any quantum model for the emission and absorption of electromagnetic radiation must include to account for the gas spectra and we then design two questionnaires, one for teachers and the other for students. By analyzing the responses, we conclude that (i) teachers lack a quantum model for the emission and absorption of electromagnetic radiation capable of explaining the spectra, (ii) teachers and students share the same difficulties, and (iii) these difficulties concern the model of the atom, the model of radiation, and the model of the interaction between them.
Resumo:
Esta é uma investigação em linguística aplicada que, ao procurar perceber melhor o modo como o processo de aprendizagem do aprendente chinês de português como língua estrangeira(PLE)pode ser afetado pela aquisição do significado metafórico, assume um pendor linguístico, não deixando de se situar no âmago do ato pedagógico. Admitindo a hipótese da existência de uma correlação positiva entre a frequência do uso da metáfora gramatical e o nível de proficiência dos aprendentes na expressão escrita, esta dissertação pretende aprofundar a compreensão dos mecanismos de aquisição do Português por aprendentes (PLE/PL2) que têm como língua materna o Chinês, designadamente os que se prendem com a aquisição de processos metafóricos. Neste estudo, teremos como referência a teorização sobre o significado metafórico proposto por Halliday (1985, 1994, 2004). A ocorrência de metáforas gramaticais foi escrutinada emdois manuais de ensino de PLE concebidos para os níveis A2 e B1 do QECR, de forma a poder identificar, qualitativa e quantitativamente, os padrões textuais metafóricos com que os aprendentes têm que lidar nestes momentos específicos do processo de aprendizagem. Para compreender a produção escrita de pendor metafórico dos aprendentes, é realizada análise sistemática de amostras da expressão escrita de alunos de PLE chineses dos mesmos dois níveis, constantes no Corpus de Português Língua Estrangeira/Língua Segunda, COPLE2. Do confronto dos dados dos dois planos de análise, foi possível confirmar que a transição entre os dois níveis subsequentes escolhidos (A2 e B1) representa uma mudança crucial no padrão metafórico, quer dos textos propostos aos aprendentes, quer dos textos por estes produzidos, mudança esta que pode explicar alguns dos bloqueios de aprendizagem associados ao nível B1 e seguintes. Foi possível, entre outros aspetos, identificar a primazia da metáfora ideacional na acomodação da expressão metafórica, compreender como o aprendente evita o recurso metafórico, tornando a sua escrita menos abstrata e densa, como o aprendente aborda a metáfora interpessoal, restringindo o seu uso a géneros discursivos muito específicos. Sendo, embora, um estudo exploratório, permite confirmar que esta linha de investigação oferece dados inestimáveis aos professores de PLE e agentes de ensino, em geral.