56 resultados para Conjunctions
Resumo:
In three experiments, the authors investigated the impression-formation process resulting from the perception of familiar or unfamiliar social category combinations. In Experiment 1, participants were asked to generate attributes associated with either a familiar or unfamiliar social category conjunction. Compared to familiar combinations, the authors found that when the conjunction was unfamiliar, participants formed their impression less from the individual constituent categories and relatively more from novel emergent attributes. In Experiment 2 the authors replicated this effect using alternative experimental materials. In Experiment 3, the effect generalized to additional (orthogonally combined) gender and occupation categories. The implications of these findings for understanding the processes involved in the conjunction of social categories, and the formation of new stereotypes, are discussed.
Resumo:
PURPOSE: To verify the use of conjunctions in narratives, and to investigate the influence of stimuli's complexity over the type of conjunctions used by children with specific language impairment (SLI) and children with typical language development. METHODS: Participants were 40 children (20 with typical language development and 20 with SLI) with ages between 7 and 10 years, paired by age range. Fifteen stories with increasing of complexity were used to obtain the narratives; stories were classified into mechanical, behavioral and intentional, and each of them was represented by four scenes. Narratives were analyzed according to occurrence and classification of conjunctions. RESULTS: Both groups used more coordinative than subordinate conjunctions, with significant decrease in the use of conjunctions in the discourse of SLI children. The use of conjunctions varied according to the type of narrative: for coordinative conjunctions, both groups differed only between intentional and behavioral narratives, with higher occurrence in behavioral ones; for subordinate conjunctions, typically developing children's performance did not show differences between narratives, while SLI children presented fewer occurrences in intentional narratives, which was different from other narratives. CONCLUSION: Both groups used more coordinative than subordinate conjunctions; however, typically developing children presented more conjunctions than SLI children. The production of children with SLI was influenced by stimulus, since more complex narratives has less use of subordinate conjunctions.
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Predicate encryption (PE) is a new primitive which supports exible control over access to encrypted data. In PE schemes, users' decryption keys are associated with predicates f and ciphertexts encode attributes a that are specified during the encryption procedure. A user can successfully decrypt if and only if f(a) = 1. In this thesis, we will investigate several properties that are crucial to PE. We focus on expressiveness of PE, Revocable PE and Hierarchical PE (HPE) with forward security. For all proposed systems, we provide a security model and analysis using the widely accepted computational complexity approach. Our first contribution is to explore the expressiveness of PE. Existing PE supports a wide class of predicates such as conjunctions of equality, comparison and subset queries, disjunctions of equality queries, and more generally, arbitrary combinations of conjunctive and disjunctive equality queries. We advance PE to evaluate more expressive predicates, e.g., disjunctive comparison or disjunctive subset queries. Such expressiveness is achieved at the cost of computational and space overhead. To improve the performance, we appropriately revise the PE to reduce the computational and space cost. Furthermore, we propose a heuristic method to reduce disjunctions in the predicates. Our schemes are proved in the standard model. We then introduce the concept of Revocable Predicate Encryption (RPE), which extends the previous PE setting with revocation support: private keys can be used to decrypt an RPE ciphertext only if they match the decryption policy (defined via attributes encoded into the ciphertext and predicates associated with private keys) and were not revoked by the time the ciphertext was created. We propose two RPE schemes. Our first scheme, termed Attribute- Hiding RPE (AH-RPE), offers attribute-hiding, which is the standard PE property. Our second scheme, termed Full-Hiding RPE (FH-RPE), offers even stronger privacy guarantees, i.e., apart from possessing the Attribute-Hiding property, the scheme also ensures that no information about revoked users is leaked from a given ciphertext. The proposed schemes are also proved to be secure under well established assumptions in the standard model. Secrecy of decryption keys is an important pre-requisite for security of (H)PE and compromised private keys must be immediately replaced. The notion of Forward Security (FS) reduces damage from compromised keys by guaranteeing confidentiality of messages that were encrypted prior to the compromise event. We present the first Forward-Secure Hierarchical Predicate Encryption (FS-HPE) that is proved secure in the standard model. Our FS-HPE scheme offers some desirable properties: time-independent delegation of predicates (to support dynamic behavior for delegation of decrypting rights to new users), local update for users' private keys (i.e., no master authority needs to be contacted), forward security, and the scheme's encryption process does not require knowledge of predicates at any level including when those predicates join the hierarchy.
Resumo:
Predicate encryption is a new primitive that supports flexible control over access to encrypted data. We study predicate encryption systems, evaluating a wide class of predicates. Our systems are more expressive than the existing attribute-hiding systems in the sense that the proposed constructions support not only all existing predicate evaluations but also arbitrary conjunctions and disjunctions of comparison and subset queries. Toward our goal, we propose encryption schemes supporting multi-inner-product predicate and provide formal security analysis. We show how to apply the proposed schemes to achieve all those predicate evaluations.
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This study describes the use of utterances ending in the conjunctions "ja" (‘and’), "mutta" (‘but’) or "että" (‘that’/‘so’) in Finnish conversation. It argues that in spoken interaction, these conjunctions are not only used as linking elements but also as final elements in interactional and linguistic units. In contrast to more traditional views, the study shows that final conjunctions do not always indicate incompleteness or project continuation, but that they can also form recognizable points for turn-transition. In these contexts they can be reanalyzed as final particles that leave some aspect of the turn implicit. The data for the study consist of audio-taped telephone conversations and videotaped service encounters. Situated within the framework of conversation analysis and interactional linguistics, the study discusses the interactional uses of conjunction-final turns and their recognizability as possibly complete units in talk-in-interaction. The analysis of conjunction-final utterances focuses on 1) participant orientation, and 2) their recurrent contexts of use. The results show that the recipients of conjunction-final utterances often treat them as sufficient and complete in their contexts by displaying understanding or agreement. When the same speaker continues after a pause, it is not always clear that the continuation was "planned" in advance; it can also be reactive to lack of expected uptake. In these cases, a turn can be analyzed as potentially complete even if the same speaker decides to continue after a pause. In the light of these observations, the study confirms the incremental nature of spoken language. All the final conjunctions under examination have recurrent and recognizable contexts of use. Most typically, a conjunction-final utterance is produced in the service of some earlier claim by the same speaker. The conjunction-final utterance may 1) specify the earlier claim with a detailing list ("ja"), 2) legitimize it by presenting grounds ("että") or 3) partly back down from it by making a concession ("mutta"). Together with the earlier claim, conjunction-final utterances form recognizable discourse patterns that are used for argumentative purposes. In these contexts, conjunctions are used to relinquish the floor instead of functioning as turn-holding devices. In conclusion, the study discusses the emergence of conjunctions as final particles – how their development can be explained. Conjunction-type final particles emerge from recurring situations in which the future course of the conjunction-final turn-so-far is clear enough to remain unsaid, to be left to inference. More specifically, this ability to leave something to inference often lies in the fixed discourse patterns that are conventionalized and predictable and thus reducible.
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We study the orbital modulation of X-rays from Cyg X-3, using data from Swift, INTEGRAL and RXTE. Using the wealth of data presently available and an improved averaging method, we obtain energy-dependent folded and averaged light curves with unprecedented accuracy. We find that above similar to 5?keV the modulation depth decreases with increasing energy, which is consistent with the modulation being caused by both boundfree absorption and Compton scattering in the stellar wind of the donor, with minima corresponding to the highest optical depth, which occurs around the superior conjunction. We find a decrease of the depth below similar to 3?keV, which appears to be due to re-emission of the absorbed continuum by the wind in soft X-ray lines. Based on the shape of the folded light curves, any X-ray contribution from the jet in Cyg X-3, which emits ?-rays detected at energies >0.1?GeV in the soft spectral states, is found to be minor up to similar to 100?keV. This implies the presence of a rather sharp low-energy break in the jet MeV-range spectrum. We also calculate phase-resolved RXTE X-ray spectra and show that the difference between the spectra corresponding to phases around superior and inferior conjunctions can indeed be accounted for by the combined effect of boundfree absorption in an ionized medium and Compton scattering.
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Integran este número de la revista ponencias presentadas en Studia Hispanica Medievalia VIII: Actas de las IX Jornadas Internacionales de Literatura Española Medieval, 2008, y de Homenaje al Quinto Centenario de Amadis de Gaula
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Neste estudo qualitativo, objetiva-se descrever os usos do conector mas em um corpus de mediação endoprocessual, à luz da Linguística Cognitiva, baseando-se, sobretudo, na Teoria da Metáfora Conceptual e nos conceitos de categorização, esquemas imagéticos e modelos cognitivos idealizados (MCIs). Investigam-se as bases cognitivas que fundamentam os sentidos do mas e a função argumentativa desse conector na mediação, a partir de duas hipóteses gerais, a saber: (i) defende-se que o conector mas funciona como um gatilho para a ativação do MCI de guerra, em termos do qual é conceptualizado o conceito de discussão, como afirmam Lakoff e Johnson (2002[1980]); e (ii) acredita-se que tal conector possa ser caracterizado como uma categoria radial, formada a partir dos diferentes esquemas imagéticos que fundamentam as ocorrências desse elemento na interação. Tendo em vista essas hipóteses, objetiva-se: (i) apontar as funções argumentativas do mas na mediação, sinalizadas pelos mapeamentos metafóricos ativados durante a discussão e (ii) descrever os sentidos evidenciados pelos usos do mas no gênero analisado, os quais são evocados pelos diferentes esquemas imagéticos em que se baseiam. Os resultados indicam que esse conector pode ser compreendido como uma categoria radial, formada a partir de esquemas de força distintos. Além disso, verifica-se que os três usos mais próximos ao centro da categoria relacionam-se fortemente a um confronto ou a uma disputa de posição entre os participantes da interação, enquanto os três mais periféricos são estreitamente ligados a uma estratégia de manutenção da posição argumentativa do falante. Considera-se que esta pesquisa possa colaborar para o estudo do conector mas, devido à observação do comportamento semântico-discursivo desse item em um gênero pouco contemplado, a mediação; e, devido à escolha do paradigma adotado, que permite analisar o conector em todas as suas ocorrências, não havendo necessidade de separar os usos chamados de interfrásticos daqueles denominados inícios acessórios ou pré-começos
Resumo:
O propósito deste trabalho é analisar os conetivos, ferramentas linguísticas que se propõem nos enunciados a estabelecer ligação, do ponto de vista funcional, em seus usos, e que representam valores semânticos importantes discursivamente. Para isso, será válido utilizarmos fundamentações teóricas da Linguística Textual e do Funcionalismo. O corpus de análise baseia-se em textos cuja tipologia é argumentativa, mais especificamente o gênero editorial. Dessa forma, procuraremos analisar como esses conectivos (conjunções, preposições, advérbios...) revelam marcas semânticas importantes que se constituem como verdadeiras estratégias argumentativas por parte dos autores em sua proposta temática e que precisam ser reconhecidas pelo leitor para uma compreensão textual mais abrangente. Essa forma de abordagem implicará análises de coesão e de coerência textuais e, por isso, é também uma proposta de avaliação de como os textos são constituídos em sua tessitura, resultando na produção de sentido. Os textos em análise serão os correspondentes aos editoriais da revista Veja, cujo titulo da seção chama-se Carta ao leitor. As abordagens colocarão em relevo os elementos conectores tanto do ponto de vista sintático-semântico bem como em relação às implicações pragmático-discursivas, fatores que servirão de base para compreensão/interpretação dos textos. Espera-se com isso proporcionar análises contundentes, levando em consideração a descrição, estruturação e o funcionamento da Língua portuguesa, com o objetivo de colaborar para o desenvolvimento científico das abordagens linguísticas
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A neural network model, called an FBF network, is proposed for automatic parallel separation of multiple image figures from each other and their backgrounds in noisy grayscale or multi-colored images. The figures can then be processed in parallel by an array of self-organizing Adaptive Resonance Theory (ART) neural networks for automatic target recognition. An FBF network can automatically separate the disconnected but interleaved spirals that Minsky and Papert introduced in their book Perceptrons. The network's design also clarifies why humans cannot rapidly separate interleaved spirals, yet can rapidly detect conjunctions of disparity and color, or of disparity and motion, that distinguish target figures from surrounding distractors. Figure-ground separation is accomplished by iterating operations of a Feature Contour System (FCS) and a Boundary Contour System (BCS) in the order FCS-BCS-FCS, hence the term FBF, that have been derived from an analysis of biological vision. The FCS operations include the use of nonlinear shunting networks to compensate for variable illumination and nonlinear diffusion networks to control filling-in. A key new feature of an FBF network is the use of filling-in for figure-ground separation. The BCS operations include oriented filters joined to competitive and cooperative interactions designed to detect, regularize, and complete boundaries in up to 50 percent noise, while suppressing the noise. A modified CORT-X filter is described which uses both on-cells and off-cells to generate a boundary segmentation from a noisy image.
Resumo:
A neural network model of 3-D visual perception and figure-ground separation by visual cortex is introduced. The theory provides a unified explanation of how a 2-D image may generate a 3-D percept; how figures pop-out from cluttered backgrounds; how spatially sparse disparity cues can generate continuous surface representations at different perceived depths; how representations of occluded regions can be completed and recognized without usually being seen; how occluded regions can sometimes be seen during percepts of transparency; how high spatial frequency parts of an image may appear closer than low spatial frequency parts; how sharp targets are detected better against a figure and blurred targets are detector better against a background; how low spatial frequency parts of an image may be fused while high spatial frequency parts are rivalrous; how sparse blue cones can generate vivid blue surface percepts; how 3-D neon color spreading, visual phantoms, and tissue contrast percepts are generated; how conjunctions of color-and-depth may rapidly pop-out during visual search. These explanations arise derived from an ecological analysis of how monocularly viewed parts of an image inherit the appropriate depth from contiguous binocularly viewed parts, as during DaVinci stereopsis. The model predicts the functional role and ordering of multiple interactions within and between the two parvocellular processing streams that join LGN to prestriate area V4. Interactions from cells representing larger scales and disparities to cells representing smaller scales and disparities are of particular importance.
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In two experiments we tested the prediction derived from Tversky and Kahneman's (1983) work on the causal conjunction fallacy that the strength of the causal connection between constituent events directly affects the magnitude of the causal conjunction fallacy. We also explored whether any effects of perceived causal strength were due to graded output from heuristic Type 1 reasoning processes or the result of analytic Type 2 reasoning processes. As predicted, Experiment 1 demonstrated that fallacy rates were higher for strongly than for weakly related conjunctions. Weakly related conjunctions in turn attracted higher rates of fallacious responding than did unrelated conjunctions. Experiment 2 showed that a concurrent memory load increased rates of fallacious responding for strongly related but not for weakly related conjunctions. We interpret these results as showing that manipulations of the strength of the perceived causal relationship between the conjuncts result in graded output from heuristic reasoning process and that additional mental resources are required to suppress strong heuristic output.