983 resultados para Explicit recasts


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In an article in this journal, Boeckx & Hornstein (2006a) present data from Brazilian Portuguese (BP) as an argument in favor of the Movement Theory of Control (MTC). In this reply, I show that the data presented by those authors do not necessarily argue for a movement analysis of BP finite subjects nor of nonfinite control. I also show that BP provides arguments against the MTC when inflected infinitives are considered. Inflected infinitives may be used in BP in partial control structures, which makes it explicit that a singular matrix argument may control a syntactically plural null subject and shows that these two positions cannot be related by movement. Additionally, I show that the MTC makes the wrong predictions when a language with inflected infinitives is considered.

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Qu-Prolog is an extension of Prolog which performs meta-level computations over object languages, such as predicate calculi and lambda-calculi, which have object-level variables, and quantifier or binding symbols creating local scopes for those variables. As in Prolog, the instantiable (meta-level) variables of Qu-Prolog range over object-level terms, and in addition other Qu-Prolog syntax denotes the various components of the object-level syntax, including object-level variables. Further, the meta-level operation of substitution into object-level terms is directly represented by appropriate Qu-Prolog syntax. Again as in Prolog, the driving mechanism in Qu-Prolog computation is a form of unification, but this is substantially more complex than for Prolog because of Qu-Prolog's greater generality, and especially because substitution operations are evaluated during unification. In this paper, the Qu-Prolog unification algorithm is specified, formalised and proved correct. Further, the analysis of the algorithm is carried out in a frame-work which straightforwardly allows the 'completeness' of the algorithm to be proved: though fully explicit answers to unification problems are not always provided, no information is lost in the unification process.

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The refinement calculus provides a framework for the stepwise development of imperative programs from specifications. In this paper we study a refinement calculus for deriving logic programs. Dealing with logic programs rather than imperative programs has the dual advantages that, due to the expressive power of logic programs, the final program is closer to the original specification, and each refinement step can achieve more. Together these reduce the overall number of derivation steps. We present a logic programming language extended with specification constructs (including general predicates, assertions, and types and invariants) to form a wide-spectrum language. General predicates allow non-executable properties to be included in specifications. Assertions, types and invariants make assumptions about the intended inputs of a procedure explicit, and can be used during refinement to optimize the constructed logic program. We provide a semantics for the extended logic programming language and derive a set of refinement laws. Finally we apply these to an example derivation.

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A fully explicit formula for the eigenvalues of Casimir invariants for U-q(gl(m/n)) is given which applies to all unitary irreps. This is achieved by making some interesting observations on atypicality indices for irreps occurring in the tensor product of unitary irreps of the same type. These results have applications in the determination of link polynomials arising from unitary irreps of U-q(gl(m/n)).

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An algorithm for explicit integration of structural dynamics problems with multiple time steps is proposed that averages accelerations to obtain subcycle states at a nodal interface between regions integrated with different time steps. With integer time step ratios, the resulting subcycle updates at the interface sum to give the same effect as a central difference update over a major cycle. The algorithm is shown to have good accuracy, and stability properties in linear elastic analysis similar to those of constant velocity subcycling algorithms. The implementation of a generalised form of the algorithm with non-integer time step ratios is presented. (C) 1997 by John Wiley & Sons, Ltd.

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The popular Newmark algorithm, used for implicit direct integration of structural dynamics, is extended by means of a nodal partition to permit use of different timesteps in different regions of a structural model. The algorithm developed has as a special case an explicit-explicit subcycling algorithm previously reported by Belytschko, Yen and Mullen. That algorithm has been shown, in the absence of damping or other energy dissipation, to exhibit instability over narrow timestep ranges that become narrower as the number of degrees of freedom increases, making them unlikely to be encountered in practice. The present algorithm avoids such instabilities in the case of a one to two timestep ratio (two subcycles), achieving unconditional stability in an exponential sense for a linear problem. However, with three or more subcycles, the trapezoidal rule exhibits stability that becomes conditional, falling towards that of the central difference method as the number of subcycles increases. Instabilities over narrow timestep ranges, that become narrower as the model size increases, also appear with three or more subcycles. However by moving the partition between timesteps one row of elements into the region suitable for integration with the larger timestep these the unstable timestep ranges become extremely narrow, even in simple systems with a few degrees of freedom. As well, accuracy is improved. Use of a version of the Newmark algorithm that dissipates high frequencies minimises or eliminates these narrow bands of instability. Viscous damping is also shown to remove these instabilities, at the expense of having more effect on the low frequency response.

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Objective: The aim of this article is to propose an integrated framework for extracting and describing patterns of disorders from medical images using a combination of linear discriminant analysis and active contour models. Methods: A multivariate statistical methodology was first used to identify the most discriminating hyperplane separating two groups of images (from healthy controls and patients with schizophrenia) contained in the input data. After this, the present work makes explicit the differences found by the multivariate statistical method by subtracting the discriminant models of controls and patients, weighted by the pooled variance between the two groups. A variational level-set technique was used to segment clusters of these differences. We obtain a label of each anatomical change using the Talairach atlas. Results: In this work all the data was analysed simultaneously rather than assuming a priori regions of interest. As a consequence of this, by using active contour models, we were able to obtain regions of interest that were emergent from the data. The results were evaluated using, as gold standard, well-known facts about the neuroanatomical changes related to schizophrenia. Most of the items in the gold standard was covered in our result set. Conclusions: We argue that such investigation provides a suitable framework for characterising the high complexity of magnetic resonance images in schizophrenia as the results obtained indicate a high sensitivity rate with respect to the gold standard. (C) 2010 Elsevier B.V. All rights reserved.

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Aim: To identify how the methodology of Reflection Groups (RG) can contribute to approach social-psychological problems, so often observed as obstacles in PE efforts. The objective was also to verify the contributions from RG to the implementation of ergonomics recommendations, which were a starting point and organized group discussions. Method: A concrete case was used as an illustration, and studied in depth: RG with administration and production workers` representatives from the Department of Nutrition and Dietetics of a cardiologic hospital in Sao Paulo, Brazil. RG are temporary thinking groups, taking place outside the workplace and having delegative and consultive participation. They make use of Operative Groups, an adapted form of tripartite group, activity as an instrumental resource, group dynamic techniques and videotaping. In 2007, 31 meetings took place during paid working hours with 7 groups of different composition, ranging from 1.5 h to 3 h. Results: Additionally to the positive effects in communication and psychosocial environment, RG could also contribute to changes in interpersonal relationships, cooperation, personal and work behaviours. By dealing with aspects which could hinder the explicit task: fears, conflicts, and stereotyped beliefs and behaviours; resistance to change could be broken and group members could learn. RG allowed input about new risks; continuous information and feedback about ongoing ergonomics interventions so that immediate corrective action could be taken. The main form of participation was in administrative, organizational, and psychosocial problems which required a better clarification and identification of their real causes, commitment, and elaboration of strategies and negotiation of different stakeholders in their solution. Conclusion: RG takes advantage of homogeneous and heterogeneous groups, in face to face communication. The interactions in the groups are task-oriented (explicit task) but attaining groups` goals depends on a relational interaction (implicit task). Relevance to industry: Reflection groups can bring important contributions to ergonomics and industry because they favour the discussion, disclosure of problems and incorporation of solutions, enabling interventions in working organization, psychosocial environment and relationships in a collective and participatory approach, promoting health and social integration. (C) 2010 Elsevier B.V. All rights reserved.

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Purpose: Because of the controversial biologic tolerance and management, retained intraorbital metallic foreign body (RIMFb) poses a formidable challenge to surgeons. Besides location of the foreign body, indications for surgical management include neurologic injury, mechanical restriction of the eye movement, and development of local infection or draining fistula. The authors describe an unusual case of spontaneous migration of a RIMFb. Methods: A 26-year-old man had a gunshot injury on the left orbit. The patient was initially managed conservatively because of the posterior position of the bullet fragment. Thereafter, because of the clinical impairments and anterior migration of projectile, surgical treatment was considered. Results: Spontaneous anterior migration has led to mechanical disturbances and inflammatory complications that comprise explicit surgical indications for removal. The patient underwent surgery with complete relief of symptoms. We suppose that extrinsic ocular muscles might play a role in shifting large RIMFb over time, leading to change in the management strategies. Conclusions: Spontaneous migration of RIMFb is a rare clinical situation that can lead to pain, local deformity, as well as changes in the management strategies of the affected patients even in the late phase of follow-up.

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The sudden release of a mass of fluid in a channel generates a highly unsteady flow motion, called dam break wave. While industrial fluids exhibit sometimes non-Newtonian behaviours, the viscous fluid flow assumption remains a useful approximation for simplified analyses. In this study, new solutions of laminar dam break wave are proposed for a semi-infinite reservoir based upon the method of characteristics. The solutions yield simple explicit expressions of the wave front location, wave front celerity and instantaneous free-surface profiles that compare favourably with experimental observations. Both horizontal and sloping channel configurations are treated. The simplicity of the equations may allow future extension to more complicated fluid flows.

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Authorised trustee status is a legal concept which has economic implications; one of the major implications is that it assists in the direction of investment funds into particular securities and areas of the economy. The concept of authorised trustee status, while attempting to achieve specific outcomes for the beneficiaries of trusts cannot be relied upon to secure these results. Economic analysis of the role of the trustee maintains that this role is one of portfolio manager; a role which is complex but which is explicable in terms of definable procedures and practices. The role of trustee as portfolio manager is one which requires greater financial knowledge than can be assumed is possessed by all trustees. The trustee as portfolio manager is required to maintain a review of decisions make under powers to invest trust assets. A solution to the problem of authorised trustee status is proposed. The solution takes two parts: the first is the adoption of the prudent person approach but with the codification of duties of the trustee and the explicit listing of the factors that a trustee should consider in using the investment powers. The second part of the proposed solution is to link the investment powers of trustees to the best practice features of securities advisers who are now licensed by a regulatory body, the Australian Securities and Investment Commission.

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The report was commissioned by the Department of Education, Science and Training to investigate the perceived efficacy of middle years programmes in all States and Territories in improving the quality of teaching, learning and student outcomes, especially in literacy and numeracy and for student members of particular target groups. These target groups included students from lower socio-economic communities, Aboriginal and Torres Strait Islander communities, students with a language background other than English, rural and remote students, and students struggling with the transition from middle/upper primary to the junior secondary years. The project involved large scale national and international literature reviews on Australian and international middle years approaches as well as an analysis of key literacy and numeracy teaching and learning strategies being used. In the report, there is emergent evidence of the relative efficacy of a combination of explicit state policy, dedicated funding and curriculum and professional development frameworks that are focused on the improvement of classroom pedagogy in the middle years. The programs that evidenced the greatest current and potential value for target group students tended to have developed in state policy environments that encouraged a structural rather than adjunct approach to middle years innovations. The authors conclude that in order to translate the gains made into sustainable improvement of educational results in literacy and numeracy for target groups, there is a need for a second generation of middle years theorising, research, development and practice.

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Ligaments undergo finite strain displaying hyperelastic behaviour as the initially tangled fibrils present straighten out, combined with viscoelastic behaviour (strain rate sensitivity). In the present study the anterior cruciate ligament of the human knee joint is modelled in three dimensions to gain an understanding of the stress distribution over the ligament due to motion imposed on the ends, determined from experimental studies. A three dimensional, finite strain material model of ligaments has recently been proposed by Pioletti in Ref. [2]. It is attractive as it separates out elastic stress from that due to the present strain rate and that due to the past history of deformation. However, it treats the ligament as isotropic and incompressible. While the second assumption is reasonable, the first is clearly untrue. In the present study an alternative model of the elastic behaviour due to Bonet and Burton (Ref. [4]) is generalized. Bonet and Burton consider finite strain with constant modulii for the fibres and for the matrix of a transversely isotropic composite. In the present work, the fibre modulus is first made to increase exponentially from zero with an invariant that provides a measure of the stretch in the fibre direction. At 12% strain in the fibre direction, a new reference state is then adopted, after which the material modulus is made constant, as in Bonet and Burton's model. The strain rate dependence can be added, either using Pioletti's isotropic approximation, or by making the effect depend on the strain rate in the fibre direction only. A solid model of a ligament is constructed, based on experimentally measured sections, and the deformation predicted using explicit integration in time. This approach simplifies the coding of the material model, but has a limitation due to the detrimental effect on stability of integration of the substantial damping implied by the nonlinear dependence of stress on strain rate. At present, an artificially high density is being used to provide stability, while the dynamics are being removed from the solution using artificial viscosity. The result is a quasi-static solution incorporating the effect of strain rate. Alternate approaches to material modelling and integration are discussed, that may result in a better model.

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The present study investigated the degree to which young children's suggestible responses were related to their pragmatic language ability. In Experiment 1, forty-seven 5- and 6-year-olds were read a short picture story followed the next day by a postevent synopsis that included both consistent and misleading details about the original story. Six days later, a suggestibility effect was evident with responses to questions about the details that had been misled being less accurate than to those about details not misled. Although age significantly correlated with this effect, the relationship was not significant after controlling for the children's pragmatic language ability. The procedure in Experiment 2 was identical with the exception that the thirty-nine 5- and 6-year-olds were questioned in a format that made explicit the intended reference point of the interrogation. A suggestibility effect was now not evident nor was accuracy related to age. Taken together, these results support the position that young children's suggestibility requires a consideration not only in terms of suggestible memories but also in terms of suggestible responses that can result from incorrectly interpreting the intended message of an experimenter's questions. (C) 2001 Elsevier Science Inc. All rights reserved.

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In this paper, an attempt was made to investigate a fundamental problem related to the flexural waves excited by rectangular transducers. Due to the disadvantages of the Green's function approach for solving this problem, a direct and effective method is proposed using a multiple integral transform method and contour integration technique. The explicit frequency domain solutions obtained from this newly developed method are convenient for understanding transducer behavior and theoretical optimization and experimental calibration of rectangular transducers. The time domain solutions can then be easily obtained by using the fast Fourier transform technique. (C) 2001 Elsevier Science B.V. All rights reserved.