Contribution of structural order-disorder to the green photoluminescence of PbWO4

An intense and broad visible photoluminescence (PL) band was observed at room temperature in structurally disordered PbWO4 thin films. The scheelite lead tungstate (PbWO4) films prepared by the polymeric precursor method and annealed at different temperatures were structurally characterized by means of x-ray diffraction and atomic force microscopy analysis. Quantum-mechanical calculations showed that the local disorder of the network modifier (Pb) has a very important role in the charge transfer involved in the green PL emission. The experimental and theoretical results are in good agreement, both indicating that the generation of the intense visible PL band is related to simultaneous structural order and disorder in the scheelite PbWO4 lattice.

Optimization of algorithm to identification of duplicate tuples through similarity phonetic based on multithreading

Aiming to ensure greater reliability and consistency of data stored in the database, the data cleaning stage is set early in the process of Knowledge Discovery in Databases (KDD) and is responsible for eliminating problems and adjust the data for the later stages, especially for the stage of data mining. Such problems occur in the instance level and schema, namely, missing values, null values, duplicate tuples, values outside the domain, among others. Several algorithms were developed to perform the cleaning step in databases, some of them were developed specifically to work with the phonetics of words, since a word can be written in different ways. Within this perspective, this work presents as original contribution an optimization of algorithm for the detection of duplicate tuples in databases through phonetic based on multithreading without the need for trained data, as well as an independent environment of language to be supported for this. © 2011 IEEE.

A ordem SV/VS no português como L2 na fronteira Brasil/Paraguai: uma investigação sociofuncionalista na interface variação/aquisição

Pós-graduação em Estudos Linguísticos - IBILCE

A palavra fora da cena: aspectos da formação da escuta em processo colaborativo teatral

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos de sobreposição de palavras sobre a composição de sentenças sob controle condicional

A construção ordenada de unidades linguísticas é objeto de estudo da sintaxe e de fundamental interesse nas pesquisas do estudo do comportamento. Desempenhos sintáticos freqüentemente envolvem mudanças que ocorrem na ordem das palavras entre diferentes contextos linguísticos. O objetivo do presente estudo foi investigar a emergência da composição de sentenças escritas a partir do ensino por sobreposição de palavras com controle condicional. Pretendeu-se ainda examinar a manutenção do desempenho a partir da reaplicação do teste com novas sentenças. Um software foi elaborado para apresentação das contingências programadas de ensino, testes e registro dos dados comportamentais. Participaram do estudo seis crianças na faixa etária de oito a dez anos de uma instituição social. Quatro sentenças, duas na voz ativa e duas na voz passiva foram ensinadas aos participantes com o procedimento de sobreposição de palavras. A tarefa do participante consistia em compor sentenças escritas por meio da escolha, na tela do computador, de palavras apresentadas em ordem imprevisível. Após o ensino por sobreposição das sentenças na voz ativa e passiva, estas eram relacionadas condicionalmente à cor verde e vermelha respectivamente. Testes de substituibilidade verificavam a produção de novas sentenças. Após aproximadamente quarenta e cinco dias sem contato com as contingências experimentais, o desempenho emergente era novamente avaliado. Todos os participantes alcançaram o critério de acerto nas fases de ensino. Nos testes de substituibilidade, um participante alcançou 87,5%, dois obtiveram 75% e para os demais, a porcentagem de acerto foi de 62,5%, 50% e 37,5%. Um segundo estudo foi conduzido ampliando o número de tentativas de ensino para três dos participantes que tiveram um desempenho com fraco controle condicional. Os resultados mostraram que dois dos participantes (LUC e DAN) obtiveram respectivamente 100% e 87,5% de acerto nos testes com novas sentenças. O participante POL alcançou apenas 62,5% de acerto nos testes. Os resultados sugerem que esse refinamento do procedimento, para dois dos participantes, produziu a emergência de sentenças com controle condicional, em relação ao desempenho desses participantes no primeiro estudo. O desempenho dos participantes no re-teste ainda é bastante discutível com manutenção para apenas um participante. O presente estudo mostra que o procedimento de ensino por sobreposição de palavras pode gerar a composição de sentenças com poucos erros. O controle condicional precisa ser bem estabelecido e variáveis como a ordem de treino precisa ser investigada.

A elaboração de um repertório semibilíngue de somatismos fraseológicos do português brasileiro para aprendizes argentinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Pedagogia histórico-crítica e alfabetização: elementos para uma perspectiva histórico-crítica do ensino da leitura e da escrita

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Higher-Order Concurrency: Expressiveness and Decidability Results

Higher-order process calculi are formalisms for concurrency in which processes can be passed around in communications. Higher-order (or process-passing) concurrency is often presented as an alternative paradigm to the first order (or name-passing) concurrency of the pi-calculus for the description of mobile systems. These calculi are inspired by, and formally close to, the lambda-calculus, whose basic computational step ---beta-reduction--- involves term instantiation. The theory of higher-order process calculi is more complex than that of first-order process calculi. This shows up in, for instance, the definition of behavioral equivalences. A long-standing approach to overcome this burden is to define encodings of higher-order processes into a first-order setting, so as to transfer the theory of the first-order paradigm to the higher-order one. While satisfactory in the case of calculi with basic (higher-order) primitives, this indirect approach falls short in the case of higher-order process calculi featuring constructs for phenomena such as, e.g., localities and dynamic system reconfiguration, which are frequent in modern distributed systems. Indeed, for higher-order process calculi involving little more than traditional process communication, encodings into some first-order language are difficult to handle or do not exist. We then observe that foundational studies for higher-order process calculi must be carried out directly on them and exploit their peculiarities. This dissertation contributes to such foundational studies for higher-order process calculi. We concentrate on two closely interwoven issues in process calculi: expressiveness and decidability. Surprisingly, these issues have been little explored in the higher-order setting. Our research is centered around a core calculus for higher-order concurrency in which only the operators strictly necessary to obtain higher-order communication are retained. We develop the basic theory of this core calculus and rely on it to study the expressive power of issues universally accepted as basic in process calculi, namely synchrony, forwarding, and polyadic communication.

Higher-order perturbative relativistic corrections to energies and properties

Relativistic effects need to be considered in quantum-chemical calculations on systems including heavy elements or when aiming at high accuracy for molecules containing only lighter elements. In the latter case, consideration of relativistic effects via perturbation theory is an attractive option. Among the available techniques, Direct Perturbation Theory (DPT) in its lowest order (DPT2) has become a standard tool for the calculation of relativistic corrections to energies and properties.In this work, the DPT treatment is extended to the next order (DPT4). It is demonstrated that the DPT4 correction can be obtained as a second derivative of the energy with respect to the relativistic perturbation parameter. Accordingly, differentiation of a suitable Lagrangian, thereby taking into account all constraints on the wave function, provides analytic expressions for the fourth-order energy corrections. The latter have been implemented at the Hartree-Fock level and within second-order Møller-Plesset perturbaton theory using standard analytic second-derivative techniques into the CFOUR program package. For closed-shell systems, the DPT4 corrections consist of higher-order scalar-relativistic effects as well as spin-orbit corrections with the latter appearing here for the first time in the DPT series.Relativistic corrections are reported for energies as well as for first-order electrical properties and compared to results from rigorous four-component benchmark calculations in order to judge the accuracy and convergence of the DPT expansion for both the scalar-relativistic as well as the spin-orbit contributions. Additionally, the importance of relativistic effects to the bromine and iodine quadrupole-coupling tensors is investigated in a joint experimental and theoretical study concerning the rotational spectra of CH2BrF, CHBrF2, and CH2FI.

The Syntax of the EPP in Irish

In this paper, I will provide a detailed analysis of the EPP, a principle of theoretical syntax, in Modern Irish. I will document previous scholarship on this issue to give a comprehensive view of ways of reconciling the syntax with the language data, as language data is key to testing theoretical predictions. I will also provide my own model incorporating the EPP into Irish. First, I will provide necessary information about the background and development of the EPP and the Minimalist system in syntax, as well as a discussion of the Irish language and the features which make it relevant to the study of the EPP. Then, I will present the models of Irish and the considerations of the EPP which have shaped and influenced my own. These models include both instances of altering the definition of the EPP to increase its universal application and of adapting models of VSO languages to fit the prevailing definition of the EPP. Lastly, I will detail my own model for Irish sentence structure, which suggests an alternate subject position in the syntax which would allow for the EPP to adapt to fit VSO word order. An analysis of passive and the unaccusative constructions, as well as support from contemporary syntactic theory, will support this model. To complete my consideration of Irish and the EPP, I will also provide a discussion of whether of not pleonastic pronouns function in Irish and how they would be accounted for in my model.

Affective and linguistic processing of speech prosody: DC potential studies

Speech melody or prosody subserves linguistic, emotional, and pragmatic functions in speech communication. Prosodic perception is based on the decoding of acoustic cues with a predominant function of frequency-related information perceived as speaker's pitch. Evaluation of prosodic meaning is a cognitive function implemented in cortical and subcortical networks that generate continuously updated affective or linguistic speaker impressions. Various brain-imaging methods allow delineation of neural structures involved in prosody processing. In contrast to functional magnetic resonance imaging techniques, DC (direct current, slow) components of the EEG directly measure cortical activation without temporal delay. Activation patterns obtained with this method are highly task specific and intraindividually reproducible. Studies presented here investigated the topography of prosodic stimulus processing in dependence on acoustic stimulus structure and linguistic or affective task demands, respectively. Data obtained from measuring DC potentials demonstrated that the right hemisphere has a predominant role in processing emotions from the tone of voice, irrespective of emotional valence. However, right hemisphere involvement is modulated by diverse speech and language-related conditions that are associated with a left hemisphere participation in prosody processing. The degree of left hemisphere involvement depends on several factors such as (i) articulatory demands on the perceiver of prosody (possibly, also the poser), (ii) a relative left hemisphere specialization in processing temporal cues mediating prosodic meaning, and (iii) the propensity of prosody to act on the segment level in order to modulate word or sentence meaning. The specific role of top-down effects in terms of either linguistically or affectively oriented attention on lateralization of stimulus processing is not clear and requires further investigations.

Theory and Practice: A Matter of Words. Language, Knowledge and Professional Community in Social Work

The relation between theory and practice in social work has always been controversial. Recently, many have underlined how language is crucial in order to capture how knowledge is used in practice. This article introduces a language perspective to the issue, rooted in the ‘strong programme’ in the sociology of knowledge and in Wittgenstein’s late work. According to this perspective, the meaning of categories and concepts corresponds to the use that concrete actors make of them as a result of on-going negotiation processes in specific contexts. Meanings may vary dramatically across social groups moved by different interests and holding different cultures. Accordingly, we may reformulate the issue of theory and practice in terms of the connections between different language games and power relationship between segments of the professional community. In this view, the point is anyway to look at how theoretical language relates to practitioners’ broader frames, and how it is transformed while providing words for making sense of experience.

Clitics, affixes, and wordhood in Garifuna (Arawak): A multidimensional continuum of morphosyntactic boundness

Recent research on wordhood and morphosyntactic boundness suggests that the domains word and clitic do not lend themselves to cross-linguistic categorization but must be defined language specifically. In most languages, it is necessary to define word on two separate levels, the phonological word (p-word) and the grammatical word (g-word), and to describe mismatches between the two. This paper defines those domains for Garifuna, an Arawak language spoken in Honduras, Central America. Garifuna has auxiliary and classifier constructions which make up two p-words, and only one g-word. P-words made up of more than one g-word involve second position enclitics, word scope clitics, and proclitic connectives and prepositions. Garifuna clitics are typically unstressed, able to attach to hosts of any word class and able to string together into clusters. Enclitics are used to express tense-aspect, modality, and adverbial meanings, among others. In other languages, clitic clusters tend to display a fixed order; Garifuna clitic order seems quite free, although certain orders are preferred. Also, contrary to cross-linguistic tendencies, proclitic connectives can act as hosts for enclitic clusters, contradicting the commonly used definition of clitics as phonologically weak elements that need to attach to a host to form a p-word; such clitic-only p-words are problematic for traditional definitions of clitics.

Automatic Understanding of ATC Speech: Study of Prospectives and Field Experiments for Several Controller Positions

Although there has been a lot of interest in recognizing and understanding air traffic control (ATC) speech, none of the published works have obtained detailed field data results. We have developed a system able to identify the language spoken and recognize and understand sentences in both Spanish and English. We also present field results for several in-tower controller positions. To the best of our knowledge, this is the first time that field ATC speech (not simulated) is captured, processed, and analyzed. The use of stochastic grammars allows variations in the standard phraseology that appear in field data. The robust understanding algorithm developed has 95% concept accuracy from ATC text input. It also allows changes in the presentation order of the concepts and the correction of errors created by the speech recognition engine improving it by 17% and 25%, respectively, absolute in the percentage of fully correctly understood sentences for English and Spanish in relation to the percentages of fully correctly recognized sentences. The analysis of errors due to the spontaneity of the speech and its comparison to read speech is also carried out. A 96% word accuracy for read speech is reduced to 86% word accuracy for field ATC data for Spanish for the "clearances" task confirming that field data is needed to estimate the performance of a system. A literature review and a critical discussion on the possibilities of speech recognition and understanding technology applied to ATC speech are also given.

Analysing written production competence descriptors for academic and professional purposes and their calibration to the CEFR

The Common European Framework of Reference for Languages (CEFR) "describes in a comprehensive way what language learners have to learn to do in order to use a language for communication and what knowledge and skills they have to develop so as to be able to act effectively" (Council of Europe, 2001: 1). This paper reports on the findings of two studies whose purpose was to assess written production competence descriptors meant for their inclusion into the Academic and Professional English Language Portfolio KELP) for students of engineering and architecture. The main objective of these studies was to establish whether the language competence descriptors were a satisfactory valid tool in their language programmes from the point of view of clarity, relevance and reliability, as perceived by the students and fellow English for Academic Purposes (RAP) / English for Science and Technology (EST) instructors. The studies shed light on how to improve unsatisfactory descriptors. Results show that the final descriptor lists were on the whole well calibrated and fairly well written: the great majority was considered valid for both teachers and students involved.