833 resultados para attribute grammars


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In this work, we investigate how hydrogen sensing performance of thermally evaporated MoO3 nanoplatelets can be further improved by RF sputtering a thin layer of tantalum oxide (Ta2O5) or lanthanum oxide (La2O3). We show that dissociated hydrogen atoms cause the thin film layer to be polarised, inducing a measurable potential difference greater than that as reported previously. We attribute these observations to the presence of numerous traps in the thin layer; their states allow a stronger trapping of charge at the Pt-thin film oxide interface as compared to the MoO3 sensors without the coating. Under exposure to H2 (10 000 ppm) the maximum change in dielectric constant of 45.6 (at 260 °C) for the Ta2O5/MoO3 nanoplatelets and 31.6 (at 220 °C) for La2O3/MoO3 nanoplatelets. Subsequently, the maximum sensitivity for the Ta2O5/MoO3 is 16.87 (at 260 °C) and La2O3/MoO3 is 7.52 (at 300 °C).

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Two approaches are described, which aid the selection of the most appropriate procurement arrangements for a building project. The first is a multi-attribute technique based on the National Economic Development Office procurement path decision chart. A small study is described in which the utility factors involved were weighted by averaging the scores of five 'experts' for three hypothetical building projects. A concordance analysis is used to provide some evidence of any abnormal data sources. When applied to the study data, one of the experts was seen to be atypical. The second approach is by means of discriminant analysis. This was found to provide reasonably consistent predictions through three discriminant functions. The analysis also showed the quality criteria to have no significant impact on the decision process. Both approaches provided identical and intuitively correct answers in the study described. Some concluding remarks are made on the potential of discriminant analysis for future research and development in procurement selection techniques.

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Given global demand for new infrastructure, governments face substantial challenges in funding new infrastructure and delivering Value for Money (VfM). As part of the background to this challenge, a critique is given of current practice in the selection of the approach to procure major public sector infrastructure in Australia and which is akin to the Multi-Attribute Utility Approach (MAUA). To contribute towards addressing the key weaknesses of MAUA, a new first-order procurement decision-making model is presented. The model addresses the make-or-buy decision (risk allocation); the bundling decision (property rights incentives), as well as the exchange relationship decision (relational to arms-length exchange) in its novel approach to articulating a procurement strategy designed to yield superior VfM across the whole life of the asset. The aim of this paper is report on the development of this decisionmaking model in terms of the procedural tasks to be followed and the method being used to test the model. The planned approach to testing the model uses a sample of 87 Australian major infrastructure projects in the sum of AUD32 billion and deploys a key proxy for VfM comprising expressions of interest, as an indicator of competition.

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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.

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Vehicle speed is an important attribute for the utility of a transport mode. The speed relationship between multiple modes of transport is of interest to the traffic planners and operators. This paper quantifies the relationship between bus speed and average car speed by integrating Bluetooth data and Transit Signal Priority data from the urban network in Brisbane, Australia. The method proposed in this paper is the first of its kind to relate bus speed and average car speed by integrating multi-source traffic data in a corridor-based method. Three transferable regression models relating not-in-service bus; in-service bus during peak; and in-service bus during off peak periods with average car are proposed. The models are cross-validated and the interrelationships are significant

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Women remain under-represented in almost all academic levels at universities internationally, and previous evidence has suggested that women move out of the university system in increasing numbers as they progress from postgraduate study to an academic career. The current study aimed to explore the role of gender in the reports of study experiences and future career plans of Australian postgraduate research students (n = 249). Questionnaire data indicated women were significantly less likely than men to rate an academic career as appealing. In particular, female postgraduate students without dependent children were least likely to want to pursue an academic career. On the basis of qualitative analysis, we attribute this finding, at least in part, to a perceived incompatibility between motherhood and an academic career and discuss the implications for gender equity in higher education.

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The term empathy has only existed in English for a little over a hundred years, but the idea of feeling with another person is an old one. Because of its perceived connection to moral behaviour, empathy and its development are of great interest to educators, policy makers, psychologists, and philosophers. Reading children’s literature is often considered important for developing (among other things) children’s ethical and empathic understandings of society and its people. However, claims as to the impact of reading on readers’ ability to become more empathic, tolerant, and better people are divided. While many readers may attribute positive influences that authors and texts have had on shaping their attitudes and actions, there is no guarantee that a desirable affective and cognitive response will follow the reading experience. The complexity of readers and texts refuses to be reduced to simple universal statements about the capacity of narrative empathy to create a particular kind of empathic reader or person: fiction that engages a reader with the emotional plight of a character does not necessarily translate into actions in the real world towards people who are similarly suffering, marginalized, or victimized. This chapter asks: Does children’s literature foster empathy? There are two implicit features of this question: one concerns narrative empathy; the other concerns empathic reader response. The discussion will focus on how a selection of ‘multicultural’ picture books attempts to create narrative empathy by focussing on cultural and spatial differences.

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Solution-phase photocatalytic reduction of graphene oxide to reduced graphene oxide (RGO) by titanium dioxide (TiO2) nanoparticles produces an RGO-TiO2 composite that possesses enhanced charge transport properties beyond those of pure TiO2 nanoparticle films. These composite films exhibit electron lifetimes up to four times longer than that of intrinsic TiO2 films due to RGO acting as a highly conducting intraparticle charge transport network within the film. The intrinsic UV-active charge generation (photocurrent) of pure TiO2 was enhanced by a factor of 10 by incorporating RGO; we attribute this to both the highly conductive nature of the RGO and to improved charge collection facilitated by the intimate contact between RGO and the TiO2, uniquely afforded by the solution-phase photocatalytic reduction method. Integrating RGO into nanoparticle films using this technique should improve the performance of photovoltaic devices that utilize nanoparticle films, such as dye-sensitized and quantum-dot-sensitized solar cells.

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Globalised communication in society today is characterised by multimodal forms of meaning making in a context of increased cultural and linguistic diversity, calling for the teaching of multiliteracies. This transformation requires the development of a new metalanguage or language of description for the burgeoning and hybridised variety of text forms associated with information and multimedia technologies. To continue to teach to a narrow band of print-based genres, grammars, and skills is to ignore the reality of textual practices outside of schools. This paper draws from classroom research in a multiliteracies classroom to provide a multimodal analysis of a claymation movie. The significance of the paper is the synthesis of a multimodal metalanguage for teachers and students to describe the features of work in the kineikonic (moving image) mode.

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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 research segments male and female food shoppers based on store and product attribute evaluations, enjoyment, planning, and shopping responsibility. A rich profile for each segment is developed from a sample of 580 primary food shoppers. Gender comparisons are operationalized and these developed food shopper typologies are contrasted against earlier works. Factor analysis, cluster analysis, and ANOVA were employed to develop specific segments of shoppers. This is the first study to identify specific groups of male food shoppers and contrast these to traditional female shoppers and earlier typographical works. The research provides the basis for further cross-cultural, cross-contextual comparative studies.

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This thesis explored the knowledge and reasoning of young children in solving novel statistical problems, and the influence of problem context and design on their solutions. It found that young children's statistical competencies are underestimated, and that problem design and context facilitated children's application of a wide range of knowledge and reasoning skills, none of which had been taught. A qualitative design-based research method, informed by the Models and Modeling perspective (Lesh & Doerr, 2003) underpinned the study. Data modelling activities incorporating picture story books were used to contextualise the problems. Children applied real-world understanding to problem solving, including attribute identification, categorisation and classification skills. Intuitive and metarepresentational knowledge together with inductive and probabilistic reasoning was used to make sense of data, and beginning awareness of statistical variation and informal inference was visible.

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“Mental illness is a tough illness to survive, it is incurable but manageable. Living with the illness when at its full potency can disrupt your life at any moment.” Intensive care for patients experiencing acute psychiatric distress is an essential yet complex part of mental health services as a whole system. Psychiatric intensive care units remain a source of controversy; despite promising developments to health services incorporating recovery goals and processes outlined by people with a mental illness themselves. In past decades changes in the provision of mental health services have focused on the restoration of a meaningful and empowered life with choice and hope as a defining attribute of recovery. Yet, what does recovery mean and how are recovery principles accomplished in psychiatric intensive care arrangements for someone experiencing acute psychiatric distress?

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Process models are used to convey semantics about business operations that are to be supported by an information system. A wide variety of professionals is targeted to use such models, including people who have little modeling or domain expertise. We identify important user characteristics that influence the comprehension of process models. Through a free simulation experiment, we provide evidence that selected cognitive abilities, learning style, and learning strategy influence the development of process model comprehension. These insights draw attention to the importance of research that views process model comprehension as an emergent learning process rather than as an attribute of the models as objects. Based on our findings, we identify a set of organizational intervention strategies that can lead to more successful process modeling workshops.

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Finite element frame analysis programs targeted for design office application necessitate algorithms which can deliver reliable numerical convergence in a practical timeframe with comparable degrees of accuracy, and a highly desirable attribute is the use of a single element per member to reduce computational storage, as well as data preparation and the interpretation of the results. To this end, a higher-order finite element method including geometric non-linearity is addressed in the paper for the analysis of elastic frames for which a single element is used to model each member. The geometric non-linearity in the structure is handled using an updated Lagrangian formulation, which takes the effects of the large translations and rotations that occur at the joints into consideration by accumulating their nodal coordinates. Rigid body movements are eliminated from the local member load-displacement relationship for which the total secant stiffness is formulated for evaluating the large member deformations of an element. The influences of the axial force on the member stiffness and the changes in the member chord length are taken into account using a modified bowing function which is formulated in the total secant stiffness relationship, for which the coupling of the axial strain and flexural bowing is included. The accuracy and efficiency of the technique is verified by comparisons with a number of plane and spatial structures, whose structural response has been reported in independent studies.