915 resultados para Orthogonal polynomials on the real line
Resumo:
Paramedics are trained to use specialized medical knowledge and a variety of medical procedures and pharmaceutical interventions to “save patients and prevent further damage” in emergency situations, both as members of “health-care teams” in hospital emergency departments (Swanson, 2005: 96) and on the streets – unstandardized contexts “rife with chaotic, dangerous, and often uncontrollable elements” (Campeau, 2008: 3). The paramedic’s unique skill-set and ability to function in diverse situations have resulted in the occupation becoming ever more important to health care systems (Alberta Health and Wellness, 2008: 12).
Today, prehospital emergency services, while varying, exist in every major city and many rural areas throughout North America (Paramedics Association of Canada, 2008) and other countries around the world (Roudsari et al., 2007). Services in North America, for instance, treat and/or transport 2 million Canadians (over 250,000 in Alberta alone ) and between 25 and 30 million Americans annually (Emergency Medical Services Chiefs of Canada, 2006; National EMS Research Agenda, 2001). In Canada, paramedics make up one of the largest groups of health care professionals, with numbers exceeding 20,000 (Pike and Gibbons, 2008; Paramedics Association of Canada, 2008). However, there is little known about the work practices of paramedics, especially in light of recent changes to how their work is organized, making the profession “rich with unexplored opportunities for research on the full range of paramedic work” (Campeau, 2008: 2).
This presentation reports on findings from an institutional ethnography that explored the work of paramedics and different technologies of knowledge and governance that intersect with and organize their work practices. More specifically, my tentative focus of this presentation is on discussing some of the ruling discourses central to many of the technologies used on the front lines of EMS in Alberta and the consequences of such governance practices for both the front line workers and their patients. In doing so, I will demonstrate how IE can be used to answer Rankin and Campbell’s (2006) call for additional research into “the social organization of information in health care and attention to the (often unintended) ways ‘such textual products may accomplish…ruling purposes but otherwise fail people and, moreover, obscure that failure’ (p. 182)” (cited in McCoy, 2008: 709).
Resumo:
The worsening of process variations and the consequent increased spreads in circuit performance and consumed power hinder the satisfaction of the targeted budgets and lead to yield loss. Corner based design and adoption of design guardbands might limit the yield loss. However, in many cases such methods may not be able to capture the real effects which might be way better than the predicted ones leading to increasingly pessimistic designs. The situation is even more severe in memories which consist of substantially different individual building blocks, further complicating the accurate analysis of the impact of variations at the architecture level leaving many potential issues uncovered and opportunities unexploited. In this paper, we develop a framework for capturing non-trivial statistical interactions among all the components of a memory/cache. The developed tool is able to find the optimum memory/cache configuration under various constraints allowing the designers to make the right choices early in the design cycle and consequently improve performance, energy, and especially yield. Our, results indicate that the consideration of the architectural interactions between the memory components allow to relax the pessimistic access times that are predicted by existing techniques.
Resumo:
Most cryptographic devices should inevitably have a resistance against the threat of side channel attacks. For this, masking and hiding schemes have been proposed since 1999. The security validation of these countermeasures is an ongoing research topic, as a wider range of new and existing attack techniques are tested against these countermeasures. This paper examines the side channel security of the balanced encoding countermeasure, whose aim is to process the secret key-related data under a constant Hamming weight and/or Hamming distance leakage. Unlike previous works, we assume that the leakage model coefficients conform to a normal distribution, producing a model with closer fidelity to real-world implementations. We perform analysis on the balanced encoded PRINCE block cipher with simulated leakage model and also an implementation on an AVR board. We consider both standard correlation power analysis (CPA) and bit-wise CPA. We confirm the resistance of the countermeasure against standard CPA, however, we find with a bit-wise CPA that we can reveal the key with only a few thousands traces.
Resumo:
AIM:
To utilise a novel method for making measurements in the anterior chamber in order to compare the anterior chamber angles of people of European, African, and east Asian descent aged 40 years and over.
METHODS:
A cross sectional study on 15 people of each sex from each decade from the 40s to the 70s, from each of three racial groups-black, white, and Chinese Singaporeans. Biometric gonioscopy (BG) utilises a slit lamp mounted reticule to make measurements from the apparent iris insertion to Schwalbe's line through a Goldmann one mirror goniolens. The main outcome measures were BG measurements of the anterior chamber angle as detailed above.
RESULTS:
There was no significant difference in angle measurement between black, white, and Chinese races in this study. However, at younger ages people of Chinese race appeared to have deeper angles than white or black people, whereas the angles of older Chinese were significantly narrower (p = 0.004 for the difference in slope of BG by age between Chinese and both black and white people).
CONCLUSION:
The failure to detect a difference in angle measurements between these groups was surprising, given the much higher prevalence of angle closure among Chinese. It appears that the overall apparent similarity of BG means between Chinese and Western populations may mask very different trends with age. The apparently more rapid decline in angle width measurements with age among Chinese may be due to the higher prevalence of cataract or "creeping angle closure." However, longitudinal inferences from cross sectional data are problematic, and this may represent a cohort phenomenon caused by the increasing prevalence of myopia in the younger Singaporean population.
Resumo:
We present complete collisional-radiative modelling results for the soft x-ray emission lines of Fe16+ in the 15 Å–17 Å range. These lines have been the subject of much controversy in the astrophysical and laboratory plasma community. Radiative transition rates are generated from fully relativistic atomic structure calculations. Electron-impact excitation cross sections are determined using a fully relativistic R-matrix method employing 139 coupled atomic levels through n = 5. We find that, in all cases, using a simple ratio of the collisional rate coefficient times a radiative branching factor is not sufficient to model the widely used diagnostic line ratios. One has to include the effects of collisional-radiative cascades in a population model to achieve accurate line ratios. Our line ratio results agree well with several previous calculations and reasonably well with tokamak experimental measurements, assuming a Maxwellian electron-energy distribution. Our modelling results for four EBIT line ratios, assuming a narrow Gaussian electron-energy distribution, are in generally poor agreement with all four NIST measurements but are in better agreement with the two LLNL measurements. These results suggest the need for an investigation of the theoretical polarization calculations that are required to interpret the EBIT line ratio measurements.
Resumo:
The vulval pattern of six species of the genus Bursaphelenchus (B. abruptus, B. conicaudatus, B. fraudulentus, B. luxuriosae, B. mucronatus and B. xylophilus) was studied using scanning electron microscopy. A terminology for the vulval region structures observed is proposed herein and illustrated by micrographs and line drawings. It was shown that, of the studied species, only B. mucronatus and B. xylophilus share an identical morphology of the vulval region, all other species differing significantly from each other and from both B. mucronatus and B. xylophilus. This study indicates the diagnostic potential for variation in vulval morphology within Bursaphelenchus and it is recommended that such features are recorded in all future descriptions.
Resumo:
A presente tese investiga o processo de tomada de decisão na gestão de cadeias de abastecimento, utilizando um quadro de análise de opções reais. Especificamente, estudamos tópicos como o nível de inventário ideal para protecção contra a incerteza da procura, o momento para implementação de capacidade flexível em mercados onde existe complexidade no mix de produtos, o tempo para o reforço do factor trabalho visando requisitos de serviço ao mercado, e as decisões entre integração e outsourcing num ambiente de incerteza. Foram usadas metodologias de tempo discreto e contínuo para identificar o valor ideal e o calendário das opções a adoptar, quando a procura é estocástica. Além disso, foram considerados os efeitos dos requisitos dos mercados, como a complexidade na oferta de produtos e o nível de serviço. A procura é representada recorrendo a diferentes processos estocásticos, o impacto de saltos inesperados também é explorado, reforçando a generalização dos modelos a diferentes condições de negócio. A aplicabilidade dos modelos que apresentamos permite a diversificação e o enriquecimento da literatura sobre a abordagem de opções reais, no âmbito das cadeias de abastecimento. Níveis de inventário flexíveis e capacidades flexíveis são característicos das cadeias de abastecimento e podem ser usados como resposta à incerteza do mercado. Esta tese é constituída por ensaios que suportam a aplicação dos modelos, e consiste num capítulo introdutório (designado por ensaio I) e mais seis ensaios sobre factores que discutem o uso de medidas de flexibilidade nas cadeias de abastecimento, em ambientes de incerteza, e um último ensaio sobre a extensão do conceito de flexibilidade ao tratamento da avaliação de planos de negócio. O segundo ensaio que apresentamos é sobre o valor do inventário num único estádio, enquanto medida de flexibilidade, sujeita ao crescente condicionalismo dos custos com posse de activos. Introduzimos uma nova classificação de artigos para suportar o indicador designado por overstock. No terceiro e quarto ensaio ampliamos a exploração do conceito de overstock, promovendo a interacção e o balanceamento entre vários estádios de uma cadeia de abastecimento, como forma de melhorar o desempenho global. Para sustentar a aplicação prática das abordagens, adaptamos o ensaio número três à gestão do desempenho, para suportar o estabelecimento de metas coordenadas e alinhadas; e adaptamos o quarto ensaio à coordenação das cadeias de abastecimento, como auxiliar ao planeamento integrado e sequencial dos níveis de inventário. No ensaio cinco analisamos o factor de produção “tecnologia”, em relação directa com a oferta de produtos de uma empresa, explorando o conceito de investimento, como medida de flexibilidade nas componentes de volume da procura e gama de produtos. Dedicamos o ensaio número seis à análise do factor de produção “Mão-de-Obra”, explorando as condicionantes para aumento do número de turnos na perspectiva económica e determinando o ponto crítico para a tomada de decisão em ambientes de incerteza. No ensaio número sete exploramos o conceito de internalização de operações, demarcando a nossa análise das demais pela definição do momento crítico que suporta a tomada de decisão em ambientes dinâmicos. Complementamos a análise com a introdução de factores temporais de perturbação, nomeadamente, o estádio de preparação necessário e anterior a uma eventual alteração de estratégia. Finalmente, no último ensaio, estendemos a análise da flexibilidade em ambientes de incerteza ao conceito de planos de negócio. Em concreto, exploramos a influência do número de pontos de decisão na flexibilidade de um plano, como resposta à crescente incerteza dos mercados. A título de exemplo, usamos o mecanismo de gestão sequencial do orçamento para suportar o nosso modelo. A crescente incerteza da procura obrigou a um aumento da agilidade e da flexibilidade das cadeias de abastecimento, limitando o uso de muitas das técnicas tradicionais de suporte à gestão, pela incapacidade de incorporarem os efeitos da incerteza. A flexibilidade é claramente uma vantagem competitiva das empresas que deve, por isso, ser quantificada. Com os modelos apresentados e com base nos resultados analisados, pretendemos demonstrar a utilidade da consideração da incerteza nos instrumentos de gestão, usando exemplos numéricos para suportar a aplicação dos modelos, o que claramente promove a aproximação dos desenvolvimentos aqui apresentados às práticas de negócio.
Resumo:
REVERIE (REal and Virtual Engagement in Realistic Immersive Environments) [1] is a multimedia and multimodal framework, which supports the creation of immersive games. The framework supports the creation of games integrating technologies such as 3D spatial audio, detection of the player’s body movement using Kinect and WIMO sensors, NPCs (Non-Playable Characters) with advanced AI capabilities featuring various levels of representation and gameplay into an immersive 3D environment. A demonstration game was developed for REVERIE, which is an adapted version of the popular Simon Says game. In the REVERIE version, a player tries to follow physical instructions issued by two autonomous agents with different degrees of realism. If a player follows a physical instruction correctly, they are awarded one point. If not, they are deducted one point. This paper presents a technical overview of the game technologies integrated in the Simon Says demo and its evaluation by players with variable computer literacy skills. Finally the potential of REVERIE as an immersive framework for gaming is discussed, followed by recommendations for improvements in future versions of the framework.
Resumo:
Report of a research project of the Fachhochschule Hannover, University of Applied Sciences and Arts, Department of Information Technologies. Automatic face recognition increases the security standards at public places and border checkpoints. The picture inside the identification documents could widely differ from the face, that is scanned under random lighting conditions and for unknown poses. The paper describes an optimal combination of three key algorithms of object recognition, that are able to perform in real time. The camera scan is processed by a recurrent neural network, by a Eigenfaces (PCA) method and by a least squares matching algorithm. Several examples demonstrate the achieved robustness and high recognition rate.
Resumo:
In this paper we carry out a detailed performance analysis of a novel blind-source-seperation (BSS) based DSP algorithm that tackles the carrier phase synchronization error problem. The results indicate that the mismatch can be effectively compensated during the normal operation as well as in the rapidly changing environments. Since the compensation is carried out before any modulation specific processing, the proposed method works with all standard modulation formats and lends itself to efficient real-time custom integrated hardware or software implementations.
Resumo:
Tese de doutoramento, Geologia (Geodinâmica Interna), Universidade de Lisboa, Faculdade de Ciências, 2015
Resumo:
This article argues that the emergence of a trans-disciplinary discourse of ‘visual culture’ must be understood as, above all, a constitutively urban phenomenon. More specifically, it is in the historically new form of the capitalist metropolis, as described most famously by Simmel, that the ‘hyper-stimulus’ of modern visual culture has its social and spatial conditions. Paradoxically, however, it is as a result of this that visual culture studies is also intrinsically ‘haunted’ by a certain spectre of the invisible: one rooted in those forms of ‘real abstraction’ which Marx identifies with the commodity and the money form. Considering, initially, the canonical urban visual forms of the collage and the spectacle, these are each read in a certain relation to Simmel’s account of metropolitan life and of the money form, and, through this, to what the author claims are those forms of social and spatial abstraction that must be understood to animate them. Finally, the article returns to the entanglement of the visible and invisible entailed by this, and concludes by making some tentative suggestions about something like a paradoxical urban ‘aesthetic’ of abstraction on such a basis.
Resumo:
The use of multicores is becoming widespread inthe field of embedded systems, many of which have real-time requirements. Hence, ensuring that real-time applications meet their timing constraints is a pre-requisite before deploying them on these systems. This necessitates the consideration of the impact of the contention due to shared lowlevel hardware resources like the front-side bus (FSB) on the Worst-CaseExecution Time (WCET) of the tasks. Towards this aim, this paper proposes a method to determine an upper bound on the number of bus requests that tasks executing on a core can generate in a given time interval. We show that our method yields tighter upper bounds in comparison with the state of-the-art. We then apply our method to compute the extra contention delay incurred by tasks, when they are co-scheduled on different cores and access the shared main memory, using a shared bus, access to which is granted using a round-robin arbitration (RR) protocol.
Resumo:
The current industry trend is towards using Commercially available Off-The-Shelf (COTS) based multicores for developing real time embedded systems, as opposed to the usage of custom-made hardware. In typical implementation of such COTS-based multicores, multiple cores access the main memory via a shared bus. This often leads to contention on this shared channel, which results in an increase of the response time of the tasks. Analyzing this increased response time, considering the contention on the shared bus, is challenging on COTS-based systems mainly because bus arbitration protocols are often undocumented and the exact instants at which the shared bus is accessed by tasks are not explicitly controlled by the operating system scheduler; they are instead a result of cache misses. This paper makes three contributions towards analyzing tasks scheduled on COTS-based multicores. Firstly, we describe a method to model the memory access patterns of a task. Secondly, we apply this model to analyze the worst case response time for a set of tasks. Although the required parameters to obtain the request profile can be obtained by static analysis, we provide an alternative method to experimentally obtain them by using performance monitoring counters (PMCs). We also compare our work against an existing approach and show that our approach outperforms it by providing tighter upper-bound on the number of bus requests generated by a task.
Resumo:
Bonded unions are gaining importance in many fields of manufacturing owing to a significant number of advantages to the traditional fastening, riveting, bolting and welding techniques. Between the available bonding configurations, the single-lap joint is the most commonly used and studied by the scientific community due to its simplicity, although it endures significant bending due to the non-collinear load path, which negatively affects its load bearing capabilities. The use of material or geometric changes in single-lap joints is widely documented in the literature to reduce this handicap, acting by reduction of peel and shear peak stresses at the damage initiation sites in structures or alterations of the failure mechanism emerging from local modifications. In this work, the effect of hole drilling at the overlap on the strength of single-lap joints was analyzed experimentally with two main purposes: (1) to check whether or not the anchorage effect of the adhesive within the holes is more preponderant than the stress concentrations near the holes, arising from the sharp edges, and modification of the joints straining behaviour (strength improvement or reduction, respectively) and (2) picturing a real scenario on which the components to be bonded are modified by some external factor (e.g. retrofitting of decaying/old-fashioned fastened unions). Tests were made with two adhesives (a brittle and a ductile one) varying the adherend thickness and the number, layout and diameter of the holes. Experimental testing showed that the joints strength never increases from the un-modified condition, showing a varying degree of weakening, depending on the selected adhesive and hole drilling configuration.