912 resultados para Pointers of performance


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Many exchange rate papers articulate the view that instabilities constitute a major impediment to exchange rate predictability. In this thesis we implement Bayesian and other techniques to account for such instabilities, and examine some of the main obstacles to exchange rate models' predictive ability. We first consider in Chapter 2 a time-varying parameter model in which fluctuations in exchange rates are related to short-term nominal interest rates ensuing from monetary policy rules, such as Taylor rules. Unlike the existing exchange rate studies, the parameters of our Taylor rules are allowed to change over time, in light of the widespread evidence of shifts in fundamentals - for example in the aftermath of the Global Financial Crisis. Focusing on quarterly data frequency from the crisis, we detect forecast improvements upon a random walk (RW) benchmark for at least half, and for as many as seven out of 10, of the currencies considered. Results are stronger when we allow the time-varying parameters of the Taylor rules to differ between countries. In Chapter 3 we look closely at the role of time-variation in parameters and other sources of uncertainty in hindering exchange rate models' predictive power. We apply a Bayesian setup that incorporates the notion that the relevant set of exchange rate determinants and their corresponding coefficients, change over time. Using statistical and economic measures of performance, we first find that predictive models which allow for sudden, rather than smooth, changes in the coefficients yield significant forecast improvements and economic gains at horizons beyond 1-month. At shorter horizons, however, our methods fail to forecast better than the RW. And we identify uncertainty in coefficients' estimation and uncertainty about the precise degree of coefficients variability to incorporate in the models, as the main factors obstructing predictive ability. Chapter 4 focus on the problem of the time-varying predictive ability of economic fundamentals for exchange rates. It uses bootstrap-based methods to uncover the time-specific conditioning information for predicting fluctuations in exchange rates. Employing several metrics for statistical and economic evaluation of forecasting performance, we find that our approach based on pre-selecting and validating fundamentals across bootstrap replications generates more accurate forecasts than the RW. The approach, known as bumping, robustly reveals parsimonious models with out-of-sample predictive power at 1-month horizon; and outperforms alternative methods, including Bayesian, bagging, and standard forecast combinations. Chapter 5 exploits the predictive content of daily commodity prices for monthly commodity-currency exchange rates. It builds on the idea that the effect of daily commodity price fluctuations on commodity currencies is short-lived, and therefore harder to pin down at low frequencies. Using MIxed DAta Sampling (MIDAS) models, and Bayesian estimation methods to account for time-variation in predictive ability, the chapter demonstrates the usefulness of suitably exploiting such short-lived effects in improving exchange rate forecasts. It further shows that the usual low-frequency predictors, such as money supplies and interest rates differentials, typically receive little support from the data at monthly frequency, whereas MIDAS models featuring daily commodity prices are highly likely. The chapter also introduces the random walk Metropolis-Hastings technique as a new tool to estimate MIDAS regressions.

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Conventional Si complementary-metal-oxide-semiconductor (CMOS) scaling is fast approaching its limits. The extension of the logic device roadmap for future enhancements in transistor performance requires non-Si materials and new device architectures. III-V materials, due to their superior electron transport properties, are well poised to replace Si as the channel material beyond the 10nm technology node to mitigate the performance loss of Si transistors from further reductions in supply voltage to minimise power dissipation in logic circuits. However several key challenges, including a high quality dielectric/III-V gate stack, a low-resistance source/drain (S/D) technology, heterointegration onto a Si platform and a viable III-V p-metal-oxide-semiconductor field-effect-transistor (MOSFET), need to be addressed before III-Vs can be employed in CMOS. This Thesis specifically addressed the development and demonstration of planar III-V p-MOSFETs, to complement the n-MOSFET, thereby enabling an all III-V CMOS technology to be realised. This work explored the application of InGaAs and InGaSb material systems as the channel, in conjunction with Al2O3/metal gate stacks, for p-MOSFET development based on the buried-channel flatband device architecture. The body of work undertaken comprised material development, process module development and integration into a robust fabrication flow for the demonstration of p-channel devices. The parameter space in the design of the device layer structure, based around the III-V channel/barrier material options of Inx≥0.53Ga1-xAs/In0.52Al0.48As and Inx≥0.1Ga1-xSb/AlSb, was systematically examined to improve hole channel transport. A mobility of 433 cm2/Vs, the highest room temperature hole mobility of any InGaAs quantum-well channel reported to date, was obtained for the In0.85Ga0.15As (2.1% strain) structure. S/D ohmic contacts were developed based on thermally annealed Au/Zn/Au metallisation and validated using transmission line model test structures. The effects of metallisation thickness, diffusion barriers and de-oxidation conditions were examined. Contacts to InGaSb-channel structures were found to be sensitive to de-oxidation conditions. A fabrication process, based on a lithographically-aligned double ohmic patterning approach, was realised for deep submicron gate-to-source/drain gap (Lside) scaling to minimise the access resistance, thereby mitigating the effects of parasitic S/D series resistance on transistor performance. The developed process yielded gaps as small as 20nm. For high-k integration on GaSb, ex-situ ammonium sulphide ((NH4)2S) treatments, in the range 1%-22%, for 10min at 295K were systematically explored for improving the electrical properties of the Al2O3/GaSb interface. Electrical and physical characterisation indicated the 1% treatment to be most effective with interface trap densities in the range of 4 - 10×1012cm-2eV-1 in the lower half of the bandgap. An extended study, comprising additional immersion times at each sulphide concentration, was further undertaken to determine the surface roughness and the etching nature of the treatments on GaSb. A number of p-MOSFETs based on III-V-channels with the most promising hole transport and integration of the developed process modules were successfully demonstrated in this work. Although the non-inverted InGaAs-channel devices showed good current modulation and switch-off characteristics, several aspects of performance were non-ideal; depletion-mode operation, modest drive current (Id,sat=1.14mA/mm), double peaked transconductance (gm=1.06mS/mm), high subthreshold swing (SS=301mV/dec) and high on-resistance (Ron=845kΩ.μm). Despite demonstrating substantial improvement in the on-state metrics of Id,sat (11×), gm (5.5×) and Ron (5.6×), inverted devices did not switch-off. Scaling gate-to-source/drain gap (Lside) from 1μm down to 70nm improved Id,sat (72.4mA/mm) by a factor of 3.6 and gm (25.8mS/mm) by a factor of 4.1 in inverted InGaAs-channel devices. Well-controlled current modulation and good saturation behaviour was observed for InGaSb-channel devices. In the on-state In0.3Ga0.7Sb-channel (Id,sat=49.4mA/mm, gm=12.3mS/mm, Ron=31.7kΩ.μm) and In0.4Ga0.6Sb-channel (Id,sat=38mA/mm, gm=11.9mS/mm, Ron=73.5kΩ.μm) devices outperformed the InGaAs-channel devices. However the devices could not be switched off. These findings indicate that III-V p-MOSFETs based on InGaSb as opposed to InGaAs channels are more suited as the p-channel option for post-Si CMOS.

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Students of mumming and guising plays – the seasonal verse dramas performed for over 200 years throughout much of England, Scotland, and northern Ireland – have suffered from having too much information to work with. The first part of this poster presentation outlines and illustrates the situation. There are thousands of places where the plays are known to have been performed, and hundreds of texts have been collected. Furthermore, the plays show some tantalising similarities while simultaneously exhibiting the wide range of variation one would expect from orally transmitted dialogue. Until recently, scholars openly admitted to not knowing where to start with such a flood of material, to the extent that some dismissed the texts altogether as unimportant and irrelevant, focussing instead on the "actions". Fortunately, the introduction of computers has managed to break the impasse and is aiding the intellectual process. Part two shows a case study for one of the tools on the Master Mummers website - the Folk Play Scripts Explorer – which is based on a large database of digitised texts and a typology for individual lines. This allows researchers to search for lines, explore textual variants, and map their geographical distribution. This is yielding some interesting surprises. Seemingly trivial variations often turn out to have discrete distribution patterns, while it transpires that certain "ubiquitous" lines have restricted geographical ranges. Thus, the Scripts Explorer is providing novel insights into how the plays evolved and spread.

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Perspective taking is a crucial ability that guides our social interactions. In this study, we show how the specific patterns of errors of brain-damaged patients in perspective taking tasks can help us further understand the factors contributing to perspective taking abilities. Previous work (e.g., Samson, Apperly, Chiavarino, & Humphreys, 2004; Samson, Apperly, Kathirgamanathan, & Humphreys, 2005) distinguished two components of perspective taking: the ability to inhibit our own perspective and the ability to infer someone else’s perspective. We assessed these components using a new nonverbal false belief task which provided different response options to detect three types of response strategies that participants might be using: a complete and spared belief reasoning strategy, a reality-based response selection strategy in which participants respond from their own perspective, and a simplified mentalising strategy in which participants avoid responding from their own perspective but rely on inaccurate cues to infer the other person’s belief. One patient, with a self-perspective inhibition deficit, almost always used the reality-based response strategy; in contrast, the other patient, with a deficit in taking other perspectives, tended to use the simplified mentalising strategy without necessarily transposing her own perspective. We discuss the extent to which the pattern of performance of both patients could relate to their executive function deficit and how it can inform us on the cognitive and neural components involved in belief reasoning.

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My thesis explores the formation of the subject in the novels of Faulkner’s Go Down, Moses, Toni Morrison’s Song of Solomon, and Gloria Naylor’s Mama Day. I attach the concept of property in terms of how male protagonists are obsessed with materialistic ownership and with the subordination of women who, as properties, consolidate their manhood. The three novelists despite their racial, gendered, and literary differences share the view that identity and truth are mere social and cultural constructs. I incorporate the work of Judith Butler and other poststructuralist figures, who see identity as a matter of performance rather than a natural entity. My thesis explores the theme of freedom, which I attached to the ways characters use their bodies either to confine or to emancipate themselves from the restricting world of race, class, and gender. The three novelists deconstruct any system of belief that promulgates the objectivity of truth in historical documents. History in the three novels, as with the protagonists, perception of identity, remains a social construct laden with distortions to serve particular political or ideological agendas. My thesis gives voice to African American female characters who are associated with love and racial and gender resistance. They become the reservoirs of the African American legacy in terms of their association with the oral and intuitionist mode of knowing, which subverts the male characters’ obsession with property and with the mainstream empiricist world. In this dissertation, I use the concept of hybridity as a literary and theoretical devise that African-American writers employ. In effect, I embark on the postcolonial studies of Henry Louise Gates, Paul Gilroy, W. E. B Du Bois, James Clifford, and Arjun Appadurai in order to reflect upon the fluidity of Morrison’s and Naylor’s works. I show how these two novelists subvert Faulkner’s essentialist perception of truth, and of racial and gendered identity. They associate the myth of the Flying African with the notion of hybridity by making their male protagonists criss-cross Northern and Southern regions. I refer to Mae Gwendolyn Henderson’s article on “Speaking in Tongues” in my analysis of how Naylor subverts the patriarchal text of both Faulkner and Morrison in embarking on a more feminine version of the flying African, which she relates to an ex-slave, Sapphira Wade, a volatile female character who resists fixed claim over her story and identity. In dealing with the concept of hybridity, I show that Naylor rewrites both authors’ South by making Willow Springs a more fluid space, an assumption that unsettles the scores of critics who associate the island with authenticity and exclusive rootedness.

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The self-ordered pointing test (SOPT; Petrides & Milner, 1982) is a test of non-spatial executive working memory requiring the ability to generate and monitor a sequence of responses. Although used with developmental clinical populations there are few normative data against which to compare atypical performance. Typically developing children (5!11 years) and young adults performed two versions of the SOPT, one using pictures of familiar objects and the other hard-to-verbalise abstract designs. Performance improved with age but the children did not reach adult levels of performance. Participants of all ages found the object condition easier than the abstract condition, suggesting that verbal processes are utilised by the SOPT. However, performance on the task was largely independent from verbal and nonverbal cognitive ability. Overall the results suggest that the SOPT is a sensitive measure of executive working memory.

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Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Social e das Organizações.

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Nanostructures are highly attractive for future electrical energy storage devices because they enable large surface area and short ion transport time through thin electrode layers for high power devices. Significant enhancement in power density of batteries has been achieved by nano-engineered structures, particularly anode and cathode nanostructures spatially separated far apart by a porous membrane and/or a defined electrolyte region. A self-aligned nanostructured battery fully confined within a single nanopore presents a powerful platform to determine the rate performance and cyclability limits of nanostructured storage devices. Atomic layer deposition (ALD) has enabled us to create and evaluate such structures, comprised of nanotubular electrodes and electrolyte confined within anodic aluminum oxide (AAO) nanopores. The V2O5- V2O5 symmetric nanopore battery displays exceptional power-energy performance and cyclability when tested as a massively parallel device (~2billion/cm2), each with ~1m3 volume (~1fL). Cycled between 0.2V and 1.8V, this full cell has capacity retention of 95% at 5C rate and 46% at 150C, with more than 1000 charge/discharge cycles. These results demonstrate the promise of ultrasmall, self-aligned/regular, densely packed nanobattery structures as a testbed to study ionics and electrodics at the nanoscale with various geometrical modifications and as a building block for high performance energy storage systems[1, 2]. Further increase of full cell output potential is also demonstrated in asymmetric full cell configurations with various low voltage anode materials. The asymmetric full cell nanopore batteries, comprised of V2O5 as cathode and prelithiated SnO2 or anatase phase TiO2 as anode, with integrated nanotubular metal current collectors underneath each nanotubular storage electrode, also enabled by ALD. By controlling the amount of lithium ion prelithiated into SnO2 anode, we can tune full cell output voltage in the range of 0.3V and 3V. This asymmetric nanopore battery array displays exceptional rate performance and cyclability. When cycled between 1V and 3V, it has capacity retention of approximately 73% at 200C rate compared to 1C, with only 2% capacity loss after more than 500 charge/discharge cycles. With increased full cell output potential, the asymmetric V2O5-SnO2 nanopore battery shows significantly improved energy and power density. This configuration presents a more realistic test - through its asymmetric (vs symmetric) configuration – of performance and cyclability in nanoconfined environment. This dissertation covers (1) Ultra small electrochemical storage platform design and fabrication, (2) Electron and ion transport in nanostructured electrodes inside a half cell configuration, (3) Ion transport between anode and cathode in confined nanochannels in symmetric full cells, (4) Scale up energy and power density with geometry optimization and low voltage anode materials in asymmetric full cell configurations. As a supplement, selective growth of ALD to improve graphene conductance will also be discussed[3]. References: 1. Liu, C., et al., (Invited) A Rational Design for Batteries at Nanoscale by Atomic Layer Deposition. ECS Transactions, 2015. 69(7): p. 23-30. 2. Liu, C.Y., et al., An all-in-one nanopore battery array. Nature Nanotechnology, 2014. 9(12): p. 1031-1039. 3. Liu, C., et al., Improving Graphene Conductivity through Selective Atomic Layer Deposition. ECS Transactions, 2015. 69(7): p. 133-138.

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Thesis submitted to University of Manchester for the degree of Doctor of Philosophy in the Faculty of Business Administration.

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"This article analyses performance consumptions among young people. The theme is explored along two main axes. The first concerns the social heterogeneity in this field, considered on two levels: the different purposes for those investments – cognitive/mental and physical performance; and the different social contexts – university and work – where performance practices and dispositions may be fostered. The second axis explores the roles of pharmacological and natural consumptions, and their interrelationship, in the dissemination of these practices. The empirical data for this analysis were drawn from an ongoing research project on performance consumptions among young people (aged 18−29 years) in Portugal, including both university students and young workers without university education. The results correspond to the stage of extensive research, for which a questionnaire was organised at a national level, using non-proportional quota sampling. On the one hand, they show that (a) there is a hierarchy of acceptance of consumptions according to their purposes, with cognitive/mental performance showing higher acceptance and (b) both pharmaceuticals and natural products are consumed for every type of performance investment. On the other, the comparison between students and workers introduces a certain heterogeneity in this general backdrop, both in terms of the purposes for their consumptions and their opting for natural or pharmacological resources. These threads of heterogeneity will prompt a discussion of the dynamics of pharmaceuticalisation within the field of performance, in particular how therapeutic cultures may be changing in terms of the way individuals relate to medications, expanding their uses in social life."

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The dissertation intends to develop an investigation on the artistic existence in human beings with different bodies in society at different historical moments. In this regard and based on this scenario, the study develops a description of the stigmas production and how they are established, spread and interfere with the sociability among human beings regarded as normal and those with different bodies. Regarding the scenic arts, the text describes about the participation of artists with different bodies in the scene, specifically the freak show and postdramatic theater. The text also investigates aspects of the biography and the work of mexican artist Frida Kahlo, which underpin methodological proceedings and produce contribution to the creative process of performance Kahlo em mim Eu e(m) Kahlo , which is to investigate the practice of the scene in this dissertation

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This dissertation aims to look into the structure of the event Circuito Regional de Performance BodeArte1 to think how it collaborate with its proposal providing theoretical points to relevant questions to the comprehension of Brazilian performance art in contemporaneity, since its conceptual format until its occurrence and practical limitations. From this proposition the dissertation is organized into three chapters guided for the following aspects: the resumption of the events encompassed on the occurrence of Circuit BodeArte as well as a tabulation of the data reunited in its history, the presentation of its conceptual choices, and the metaphors conducted by the use of the term performance and how they can lead us to the idea of a performance-as-BodeArte. The methodological structures moved for this organization are qualitative, and have been formed from printed materials, texts, festival programs, blog, videos, photos, interviews, lectures and forums, plus our own memory as a producer and performer of the event, looking through these set points of the epistemological organization contained on the proposal of the Circuito, expanding and discussing them. This way this research moves between the propositions of this event in its three editions, promoting discussions that dialogue with concepts such as the emergence of Steve Johnson (2004), the metaphors of thought proposed by Christine Greiner (2005), the idea of performance hacker of Maria Beatriz de Medeiros (AQUINO, et al., 2012), as well as other propositions presented by Jan Swidzinski (2005) and Eleonora Fabião (2012)

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The aim was to describe development of a process-oriented instrument designed to assess the golf swing and putt stroke, and to assess the instrument’s discriminative validity in terms of age and reliability (intra-rater and re-test). A Delphi consultation (with golf industry professionals and researchers in movement skill assessment) was used to develop an assessment for each skill based on existing skill assessment protocols. Each skill had six components to be marked as present/absent. Individual scores were based on the number of performance components successfully demonstrated over two trials for each skill (poten-tial score range 0 to 24). Children (n = 43) aged 6-10 years (M = 7.8 years, SD = 1.3) were assessed in both skills live in the field by one rater at Time 1(T1). A subset of children (n = 28) had consent for assessments to be videoed. Six weeks later 19 chil-dren were reassessed, five days apart (T2, T3). An ANOVA assessed discriminative validity i.e. whether skill competence at T1 differed by age (6 years, 7/8 years and 9/10 years). Intraclass correlations (ICC) assessed intra-rater reliability between the live and video assessment at T1 and test-retest reliability (be-tween T2 and T3). Paired t-tests assessed any systematic differ-ences between live and video assessments (T1) and between T2 and T3. Older children were more skilled (F (2, 40) = 11.18, p < 0.001). The live assessment reflected the video assessment (ICC = 0.79, 95% CI 0.59, 0.90) and scores did not differ between live and video assessments. Test retest reliability was acceptable (ICC = 0.60, 95% CI 0.23, 0.82), although the mean score was slightly higher at retest. This instrument could be used reliably by golf coaches and physical education teachers as part of sys-tematic early player assessment and feedback.

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Drawing on interpretations of Foucault's techniques of power, we explored the discourses and power relations operative between groups of girls that appeared to influence their participation in Physical Education (PE) and outside of school in sport and physical activity (PA) in rural and regional communities. Interviews and focus groups were conducted in eight secondary schools with female students from Year 9 (n = 22) and 10 (n = 116). Dominant gendered and performance discourses were active in shaping girls’ construction of what it means to be active or ‘sporty’, and these identity positions were normalised and valued. The perceived and real threat of their peer's gaze as a form of surveillance acted to further perpetuate the power of performance discourses; whereby girls measured and (self) regulated their participation. Community settings were normalised as being exclusively for skilled performers and girls self-regulated their non-participation according to judgements made about their own physical abilities. These findings raise questions about the ways in which power relations, as forged in broader sociocultural and institutional discourse–power relations, can infiltrate the level of the PE classroom to regulate and normalise practices in relation to their, and others, PA participation.

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This research evolved out of the need to design and validate an instrument to assess nursing competencies in the operating suite. The study was an empirical investigation of the use of analytical and holistic rubrics to determine various levels of performance including inter-rater reliability. Three video clips that captured nurses performing as instrument nurses in the operating suite were recorded and used as prompts by the expert raters who judged the performance of the candidates in each video clip using the rubrics. Gaining consent for recording the video clips in the operating suite was difficult, creating a barrier to conducting this research. Ethical issues were addressed, which included editing of the video clips and removal of sound as stipulated by the Human Research and Ethics Committee. Despite the barriers to using visual art in research, this study produced acceptable inter-rater reliability in determining various levels of performance of the instrument nurse in the operating suite.