901 resultados para iterative determinant maximization
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With the increasing importance of Application Domain Specific Processor (ADSP) design, a significant challenge is to identify special-purpose operations for implementation as a customized instruction. While many methodologies have been proposed for this purpose, they all work for a single algorithm chosen from the target application domain. Such algorithm-specific approaches are not suitable for designing instruction sets applicable to a whole family of related algorithms. For an entire range of related algorithms, this paper develops a methodology for identifying compound operations, as a basis for designing “domain-specific” Instruction Set Architectures (ISAs) that can efficiently run most of the algorithms in a given domain. Our methodology combines three different static analysis techniques to identify instruction sequences common to several related algorithms: identification of (non-branching) instruction sequences that occur commonly across the algorithms; identification of instruction sequences nested within iterative constructs that are thus executed frequently; and identification of commonly-occurring instruction sequences that span basic blocks. Choosing different combinations of these results enables us to design domain-specific special operations with different desired characteristics, such as performance or suitability as a library function. To demonstrate our approach, case studies are carried out for a family of thirteen string matching algorithms. Finally, the validity of our static analysis results is confirmed through independent dynamic analysis experiments and performance improvement measurements.
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In project management today, sustainability considerations are becoming increasingly necessary as an inclusion into project discovery, design and delivery phase methodologies. However, sustainability cannot always be tacked on to traditional project management approaches and still achieve the best project outcomes. Throw in the particular considerations for a culturally specific project, as for Aboriginal and Torres Strait Islander people, and the traditional project management approach is at risk of not meeting the needs of stakeholders or their engagement. In this presentation, we will briefly demonstrate how from beginning with sustainability considerations and integrating both project management principles and Aboriginal and Torres Strait Islander va lu es that QUT's Oodgeroo Unit is actioning a 'means to ends' integration approach for stakeholder engagement in two national Aboriginal and Torres Strait Islander projects. The iterative discovery and design of the federally Higher Education Participation and Partnerships Program (HEPPP) funded Aboriginal and Torres Strait Islander Higher Education Social Marketing Strategy (Strategy) and the Aboriginal and Torres Strait Islander Higher Education Portal (Portal) projects is being informed through a 'means' to 'ends' user- and design -led project management approach for inclusivity, visioning, and participation informing these projects for susta inable national deliverables. This approach draws upon the integration of Sustain ability Development Pillars and Project Management Pillars with the contextual lens of our proposed Aboriginal and Torres Strait Islander Pillars as the underpinning methodology of the Strategy and Portal Project's Communication and Collaboration Plan and approach with stakeholders. These th ree Pillars are integrated further through participatory consideration and inclu sion of comparative models: Daly's Sustainability Triangle, Walker's Object Design, Maslow's Hierarchy of Human Needs, Olsen's Four Layers of Communication,Project Management In stitute's (PMI's) Integrated Framework for Organisational Project Management, with the Aborig inal and Torres Strait Islander six core research ethics values. This presentation invites participants to join us in envisioning the 'ultimate means' of Environment, Del ivery and Sovereignty, through Economy, Design and Self-determination to the 'ultimate ends' of Social, Discove ry and Cultural Safety principles through stakeholder engagement.
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Computational models in physiology often integrate functional and structural information from a large range of spatio-temporal scales from the ionic to the whole organ level. Their sophistication raises both expectations and scepticism concerning how computational methods can improve our understanding of living organisms and also how they can reduce, replace and refine animal experiments. A fundamental requirement to fulfil these expectations and achieve the full potential of computational physiology is a clear understanding of what models represent and how they can be validated. The present study aims at informing strategies for validation by elucidating the complex interrelations between experiments, models and simulations in cardiac electrophysiology. We describe the processes, data and knowledge involved in the construction of whole ventricular multiscale models of cardiac electrophysiology. Our analysis reveals that models, simulations, and experiments are intertwined, in an assemblage that is a system itself, namely the model-simulation-experiment (MSE) system. Validation must therefore take into account the complex interplay between models, simulations and experiments. Key points for developing strategies for validation are: 1) understanding sources of bio-variability is crucial to the comparison between simulation and experimental results; 2) robustness of techniques and tools is a pre-requisite to conducting physiological investigations using the MSE system; 3) definition and adoption of standards facilitates interoperability of experiments, models and simulations; 4) physiological validation must be understood as an iterative process that defines the specific aspects of electrophysiology the MSE system targets, and is driven by advancements in experimental and computational methods and the combination of both.
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Background: Advance Care Planning is an iterative process of discussion, decision-making and documentation about end-of-life care. Advance Care Planning is highly relevant in palliative care due to intersecting clinical needs. To enhance the implementation of Advance Care Planning, the contextual factors influencing its uptake need to be better understood. Aim: To identify the contextual factors influencing the uptake of Advance Care Planning in palliative care as published between January 2008 and December 2012. Methods: Databases were systematically searched for studies about Advance Care Planning in palliative care published between January 2008 and December 2012. This yielded 27 eligible studies, which were appraised using National Institute of Health and Care Excellence Quality Appraisal Checklists. Iterative thematic synthesis was used to group results. Results: Factors associated with greater uptake included older age, a college degree, a diagnosis of cancer, greater functional impairment, being white, greater understanding of poor prognosis and receiving or working in specialist palliative care. Barriers included having non-malignant diagnoses, having dependent children, being African American, and uncertainty about Advance Care Planning and its legal status. Individuals’ previous illness experiences, preferences and attitudes also influenced their participation. Conclusion: Factors influencing the uptake of Advance Care Planning in palliative care are complex and multifaceted reflecting the diverse and often competing needs of patients, health professionals, legislature and health systems. Large population-based studies of palliative care patients are required to develop the sound theoretical and empirical foundation needed to improve uptake of Advance Care Planning in this setting.
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In this paper we propose a novel scheme for carrying out speaker diarization in an iterative manner. We aim to show that the information obtained through the first pass of speaker diarization can be reused to refine and improve the original diarization results. We call this technique speaker rediarization and demonstrate the practical application of our rediarization algorithm using a large archive of two-speaker telephone conversation recordings. We use the NIST 2008 SRE summed telephone corpora for evaluating our speaker rediarization system. This corpus contains recurring speaker identities across independent recording sessions that need to be linked across the entire corpus. We show that our speaker rediarization scheme can take advantage of inter-session speaker information, linked in the initial diarization pass, to achieve a 30% relative improvement over the original diarization error rate (DER) after only two iterations of rediarization.
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Chaperone-usher (CU) fimbriae are adhesive surface organelles common to many Gram-negative bacteria. Escherichia coli genomes contain a large variety of characterised and putative CU fimbrial operons, however, the classification and annotation of individual loci remains problematic. Here we describe a classification model based on usher phylogeny and genomic locus position to categorise the CU fimbrial types of E. coli. Using the BLASTp algorithm, an iterative usher protein search was performed to identify CU fimbrial operons from 35 E. coli (and one Escherichia fergusonnii) genomes representing different pathogenic and phylogenic lineages, as well as 132 Escherichia spp. plasmids. A total of 458 CU fimbrial operons were identified, which represent 38 distinct fimbrial types based on genomic locus position and usher phylogeny. The majority of fimbrial operon types occupied a specific locus position on the E. coli chromosome; exceptions were associated with mobile genetic elements. A group of core-associated E. coli CU fimbriae were defined and include the Type 1, Yad, Yeh, Yfc, Mat, F9 and Ybg fimbriae. These genes were present as intact or disrupted operons at the same genetic locus in almost all genomes examined. Evaluation of the distribution and prevalence of CU fimbrial types among different pathogenic and phylogenic groups provides an overview of group specific fimbrial profiles and insight into the ancestry and evolution of CU fimbriae in E. coli.
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Autotransporter (AT) proteins are found in all Escherichia coli pathotypes and are often associated with virulence. In this study we took advantage of the large number of available E. coli genome sequences to perform an in-depth bioinformatic analysis of AT-encoding genes. Twenty-eight E. coli genome sequences were probed using an iterative approach, which revealed a total of 215 AT-encoding sequences that represented three major groups of distinct domain architecture: (i) serine protease AT proteins, (ii) trimeric AT adhesins and (iii) AIDA-I-type AT proteins. A number of subgroups were identified within each broad category, and most subgroups contained at least one characterized AT protein; however, seven subgroups contained no previously described proteins. The AIDA-I-type AT proteins represented the largest and most diverse group, with up to 16 subgroups identified from sequence-based comparisons. Nine of the AIDA-I-type AT protein subgroups contained at least one protein that possessed functional properties associated with aggregation and/or biofilm formation, suggesting a high degree of redundancy for this phenotype. The Ag43, YfaL/EhaC, EhaB/UpaC and UpaG subgroups were found in nearly all E. coli strains. Among the remaining subgroups, there was a tendency for AT proteins to be associated with individual E. coli pathotypes, suggesting that they contribute to tissue tropism or symptoms specific to different disease outcomes.
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The global financial crisis has underscored the need to pay attention to contingent government liabilities that could arise from bank failures for sovereign risk management. This paper proposes a simple method to construct a contingent liability index (CLI) for a banking sector that takes into account the size and concentration of the banking system, market expectations of bank defaults, and perceptions of government support to each bank. This method allows us to track potential government liabilities related to bank failures for 32 advanced and emerging economies on a monthly basis from 2006 to 2013. Furthermore, we find that the CLI is a significant determinant of sovereign CDS spreads. Our results suggest that a 1 percentage point increase in the CLI is associated with an increase in sovereign CDS spreads by 24 basis points for advanced economies and 75 basis points for emerging markets on average.
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The textual turn is a good friend of expert spectating, where it assumes the role of writing-productive apparatus, but no friend at all of expert practices or practitioners (Melrose, 2003). Introduction The challenge of time-based embodied performance when the artefact is unstable As a former full-time professional practitioner with an embodied dance practice as performer, choreographer and artistic director for three decades, I somewhat unexpectedly entered the world of academia in 2000 after completing a practice-based PhD, which was described by its examiners as ‘pioneering’. Like many artists my intention was to deepen and extend my practice through formal research into my work and its context (which was intercultural) and to privilege the artist’s voice in a research world where it was too often silent. Practice as research, practice-based research, and practice-led research were not yet fully named. It was in its infancy and my biggest challenge was to find a serviceable methodology which did not betray my intentions to keep practice at the centre of the research. Over the last 15 years, practice led doctoral research, where examinable creative work is placed alongside an accompanying (exegetical) written component, has come a long way. It has been extensively debated with a range of theories and models proposed (Barrett & Bolt, 2007, Pakes, 2003 & 2004, Piccini, 2005, Philips, Stock & Vincs 2009, Stock, 2009 & 2010, Riley & Hunter 2009, Haseman, 2006, Hecq, 2012). Much of this writing is based around epistemological concerns where the research methodologies proposed normally incorporate a contextualisation of the creative work in its field of practice, and more importantly validation and interrogation of the processes of the practice as the central ‘data gathering’ method. It is now widely accepted, at least in the Australian creative arts context, that knowledge claims in creative practice research arise from the material activities of the practice itself (Carter, 2004). The creative work explicated as the tangible outcome of that practice is sometimes referred to as the ‘artefact’. Although the making of the artefact, according to Colbert (2009, p. 7) is influenced by “personal, experiential and iterative processes”, mapping them through a research pathway is “difficult to predict [for] “the adjustments made to the artefact in the light of emerging knowledge and insights cannot be foreshadowed”. Linking the process and the practice outcome most often occurs through the textual intervention of an exegesis which builds, and/or builds on, theoretical concerns arising in and from the work. This linking produces what Barrett (2007) refers to as “situated knowledge… that operates in relation to established knowledge” (p. 145). But what if those material forms or ‘artefacts’ are not objects or code or digitised forms, but live within the bodies of artist/researchers where the nature of the practice itself is live, ephemeral and constantly transforming, as in dance and physical performance? Even more unsettling is when the ‘artefact’ is literally embedded and embodied in the work and in the maker/researcher; when subject and object are merged. To complicate matters, the performing arts are necessarily collaborative, relying not only on technical mastery and creative/interpretive processes, but on social and artistic relationships which collectively make up the ‘artefact’. This chapter explores issues surrounding live dance and physical performance when placed in a research setting, specifically the complexities of being required to translate embodied dance findings into textual form. Exploring how embodied knowledge can be shared in a research context for those with no experiential knowledge of communicating through and in dance, I draw on theories of “dance enaction” (Warburton, 2011) together with notions of “affective intensities” and “performance mastery” (Melrose, 2003), “intentional activity” (Pakes, 2004) and the place of memory. In seeking ways to capture in another form the knowledge residing in live dance practice, thus making implicit knowledge explicit, I further propose there is a process of triple translation as the performance (the living ‘artefact’) is documented in multi-facetted ways to produce something durable which can be re-visited. This translation becomes more complex if the embodied knowledge resides in culturally specific practices, formed by world views and processes quite different from accepted norms and conventions (even radical ones) of international doctoral research inquiry. But whatever the combination of cultural, virtual and genre-related dance practices being researched, embodiment is central to the process, outcome and findings, and the question remains of how we will use text and what forms that text might take.
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A carer or teacher often plays the role of proxy or spokesperson for a person living with an intellectual disability or form of cognitive or sensory impairment. Our research undertook co-design with people living with cognitive and sensory impairments and their proxies in order to explore new ways of facilitating communication. We developed simple functioning interactive prototypes to support people with a diverse range of competencies to communicate and explore their use. Deployment of the prototypes enabled use, appropriation and design after design by our two participant groups; adults living with cognitive or sensory impairments and children identified with language delays and autism spectrum disorder. The prototypes supported concrete expression of likes, dislikes, capabilities, emotional wants and needs and forms of expression that hitherto had not been fostered, further informing design. Carers and designers were surprised at the ways in which the technology was used and how it fostered new forms of social interaction and expression. We elaborate on how design after design can be an effective approach for engaging people living with intellectual disabilities, giving them greater capacity for expression and power in design and offering the potential to expand and deepen their social relationships.
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Background The primary health care sector delivers the majority of health care in western countries through small, community-based organizations. However, research into these healthcare organizations is limited by the time constraints and pressure facing them, and the concern by staff that research is peripheral to their work. We developed Q-RARA—Qualitative Rapid Appraisal, Rigorous Analysis—to study small, primary health care organizations in a way that is efficient, acceptable to participants and methodologically rigorous. Methods Q-RARA comprises a site visit, semi-structured interviews, structured and unstructured observations, photographs, floor plans, and social scanning data. Data were collected over the course of one day per site and the qualitative analysis was integrated and iterative. Results We found Q-RARA to be acceptable to participants and effective in collecting data on organizational function in multiple sites without disrupting the practice, while maintaining a balance between speed and trustworthiness. Conclusions The Q-RARA approach is capable of providing a richly textured, rigorous understanding of the processes of the primary care practice while also allowing researchers to develop an organizational perspective. For these reasons the approach is recommended for use in small-scale organizations both within and outside the primary health care sector.
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A multi-objective design optimization study has been conducted for upstream fuel injection through porous media applied to the first ramp of a two-dimensional scramjet intake. The optimization has been performed by coupling evolutionary algorithms assisted by surrogate modeling and computational fluid dynamics with respect to three design criteria, that is, the maximization of the absolute mixing quantity, total pressure saving, and fuel penetration. A distinct Pareto optimal front has been obtained, highlighting the counteracting behavior of the total pressure against the mixing efficiency and fuel penetration. The injector location and size have been identified as the key design parameters as a result of a sensitivity analysis, with negligible influence of the porous properties in the configurations and conditions considered in the present study. Flowfield visualization has revealed the underlying physics associated with the effects of these dominant parameters on the shock structure and intensity.
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High-Order Co-Clustering (HOCC) methods have attracted high attention in recent years because of their ability to cluster multiple types of objects simultaneously using all available information. During the clustering process, HOCC methods exploit object co-occurrence information, i.e., inter-type relationships amongst different types of objects as well as object affinity information, i.e., intra-type relationships amongst the same types of objects. However, it is difficult to learn accurate intra-type relationships in the presence of noise and outliers. Existing HOCC methods consider the p nearest neighbours based on Euclidean distance for the intra-type relationships, which leads to incomplete and inaccurate intra-type relationships. In this paper, we propose a novel HOCC method that incorporates multiple subspace learning with a heterogeneous manifold ensemble to learn complete and accurate intra-type relationships. Multiple subspace learning reconstructs the similarity between any pair of objects that belong to the same subspace. The heterogeneous manifold ensemble is created based on two-types of intra-type relationships learnt using p-nearest-neighbour graph and multiple subspaces learning. Moreover, in order to make sure the robustness of clustering process, we introduce a sparse error matrix into matrix decomposition and develop a novel iterative algorithm. Empirical experiments show that the proposed method achieves improved results over the state-of-art HOCC methods for FScore and NMI.
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A new mesh adaptivity algorithm that combines a posteriori error estimation with bubble-type local mesh generation (BLMG) strategy for elliptic differential equations is proposed. The size function used in the BLMG is defined on each vertex during the adaptive process based on the obtained error estimator. In order to avoid the excessive coarsening and refining in each iterative step, two factor thresholds are introduced in the size function. The advantages of the BLMG-based adaptive finite element method, compared with other known methods, are given as follows: the refining and coarsening are obtained fluently in the same framework; the local a posteriori error estimation is easy to implement through the adjacency list of the BLMG method; at all levels of refinement, the updated triangles remain very well shaped, even if the mesh size at any particular refinement level varies by several orders of magnitude. Several numerical examples with singularities for the elliptic problems, where the explicit error estimators are used, verify the efficiency of the algorithm. The analysis for the parameters introduced in the size function shows that the algorithm has good flexibility.
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This study investigates the effects of trait anxiety on self-reported driving behaviours through its negative impacts on Central Executive functions. Following a self-report study that found trait anxiety to be significantly related to driving behaviours, the present study extended the predictions of Eysenck and Calvo’s Attentional Control Theory, proposing that anxiety affects driving behaviours, in particular driving lapses, through its impact across the Central Executive. Seventy-five Australian drivers participated in the study, completing the Parametric Go/No-Go and n-back tasks, as well as the State-Trait Anxiety Inventory and the Driving Behaviour Questionnaire. While both trait anxiety and processing efficiency of the Central Executive was found to significantly predict driving lapses, trait anxiety remained a strong predictor of driving lapses after processing efficiency was controlled for. It is concluded that while processing efficiency of the central Executive is a key determinant of driving lapses, another Central Executive function that is closer to the driving lapses in the trait anxiety – driving lapses relationship may be needed. Suggestions regarding how to improve future trait anxiety – driving behaviours research are discussed.