911 resultados para GNSS, Ambiguity resolution, Regularization, Ill-posed problem, Success probability


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Background. Invasive Candida infection among nonneutropenic, critically ill adults is a clinical problem that has received increasing attention in recent years. Poor performance of extant diagnostic modalities has promoted risk-based, preemptive prescribing in view of the poor outcomes associated with inadequate or delayed antifungal therapy; this risks unnecessary overtreatment. A rapid, reliable diagnostic test could have a substantial impact on therapeutic practice in this patient population.

Methods. Three TaqMan-based real-time polymerase chain reaction assays were developed that are capable of detecting the main medically important Candida species, categorized according to the likelihood of fluconazole susceptibility. Assay 1 detected Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida dubliniensis. Assays 2 and 3 detected Candida glabrata and Candida krusei, respectively. The clinical performance of these assays, applied to serum, was evaluated in a prospective trial of nonneutropenic adults in a single intensive care unit.

Results. In all, 527 specimens were obtained from 157 participants. All 3 assays were run in parallel for each specimen; they could be completed within 1 working day. Of these, 23 specimens were obtained from 23 participants categorized as having proven Candida infection at the time of sampling. If a single episode of Candida famata candidemia was excluded, the estimated clinical sensitivity, specificity, and positive and negative predictive values of the assays in this trial were 90.9%, 100%, 100% and 99.8%, respectively.

Conclusions. These data suggest that the described assays perform well in this population for enhancing the diagnosis of candidemia. The extent to which they may affect clinical outcomes, prescribing practice, and cost-effectiveness of care remains to be ascertained.

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This article explores the various ways in which the Social Democratic and Labour Party (SDLP) has used Europe – as a source of financial aid, political support, ideas and inspiration – in its attempts to resolve the Northern Ireland conflict. In this, the piece considers the SDLP, not as a subject, but rather as an advocate of the Europeanization of the Northern Ireland problem. In particular, it looks at the role of John Hume, a founding member and later leader of the SDLP, who inculcated a strongly pro-European outlook within the party. In doing so, the article considers the success of Hume and the SDLP in their efforts to bring a European influence to bear on Northern Ireland, especially in relation to the peace process and the 1998 Agreement. However, it also looks at both the limitations of this influence, and the problems involved with the SDLP's pro-European approach, particularly since Hume's departure as party leader in 2001. In conclusion, the article suggests that the party may have been ‘over-Europeanized’, with its long-term focus on European issues and ideas now becoming electorally disadvantageous. In this way, the Europeanization of the Northern Ireland problem, and by extension the SDLP, has proven costly to the party.

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It is becoming clear that, contrary to earlier expectations, the application of AI techniques to law is not as easy nor as effective as some claimed. Unfortunately, for most AI researchers, there seems to be little understanding of just why this is. In this paper I argue, from empirical study of lawyers in action, just why there is a mismatch between the AI view of law, and law in practice. While this is important and novel, it also - if my arguments are accepted - demonstrates just why AI will never have success in producing the computerised lawyer.

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The construction industry notoriously excels at dispute creation – both in Ireland and world wide. This paper exams mediation in the Irish construction industry based around critical success factors in the competencies and processes required by mediators operating in the construction industry. Through conducting the relevant analysis, it was possible to extract and outline the resulting critical success factors in process and competencies of mediators in the Irish construction industry. This was achieved through a review of the literature, followed by detailed interviews from industry experts to elicit and highlight the core competencies required. To aid in the study, qualitative analysis using mind mapping software was adopted, thus assisting the identification of the key factors. Following analysis, facilitative mediation was identified as best suited for the industry in question; recommendations and experience were key for mediator selection and five and six factors were identified for mediator skills and mediation critical success factors respectively. The results returned are similar to those determined by authors in other countries and provide a good reference point for the development the industry. By following the findings of this report mediators and parties in dispute can improve processes and be more successful in outcomes. In this study the author shows that mediation is an effective and appropriate method of resolving disputes within the Irish construction industry.

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Since the first launch of the new engineering contract (NEC) in 1993, early warning of problems has been widely recognized as an important approach of proactive management during a construction or engineering project. Is early warning really effective for the improvement of problem solving and project performance? This is a research question that still lacks a good answer. For this reason, an empirical investigation was made in the United Kingdom (U.K.) to answer the question. This study adopts a combination of literature review, expert interview, and questionnaire survey. Nearly 100 questionnaire responses were collected from the U.K. construction industry, based on which the use of early warning under different forms of contract is compared in this paper. Problem solving and project performance are further compared between the projects using early warning and the projects not using early warning. The comparison provides clear evidence for the significant effect of early warning on problem solving and project performance in terms of time, cost, and quality. Subsequently, an input-process-output model is developed in this paper to explore the relationship among early warning, problem solving, and project
performance. All these help construction researchers and practitioners to better understand the role of early warning in ensuring project success.

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There has been an increasing focus on social and emotional development in educational programmes in early childhood as both variables are believed to influence behavioural outcomes in the classroom. However, relationships between social and emotional development and behaviour in early childhood have rarely been explored. This article sets out to investigate the conceptualisation of these variables and their inter-relationships. Structural equation models were used to assess if differences exist between boys and girls in relation to social and emotional competences, which could affect the relative success of such programmes. This article is based on cross-sectional data collected from 749 four- to six-year-olds and their teachers. The findings generally supported the hypothesised relationships between social and emotional development variables and prosocial behaviour (including internalising behaviour) for boys and girls. However, some gender differences were noted in externalising behaviour, which teachers often consider to be most significant due to its potentially disruptive nature in the classroom.

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It is acknowledged that one of the consequences of the ageing process is cognitive decline, which leads to an increase in the incidence of illnesses such as dementia. This has become ever more relevant due to the projected increase in the ageing demographic. Dementia affects visuo-spatial perception, causing difficulty with wayfinding, even during the early stages of the disease. The literature widely recognises the physical environment’s role in alleviating symptoms of dementia and improving quality of life for residents. It also identifies the lack of available housing options for older people with dementia and consequently the current stock is ill-equipped to provide adequate support.
Recent statistics indicate that 80% of those residing in nursing or residential care homes have some form of dementia or severe memory problems. The shift towards institutional care settings, the need for specialist support and care, places a greater impetus on the need for a person-centred approach to tackle issues related to wayfinding and dementia.
This thesis therefore aims to improve design for dementia in nursing and residential care settings in the context of Northern Ireland. This will be undertaken in order to provide a better understanding of how people with dementia experience the physical environment and to highlight features of the design that assist with wayfinding. Currently there are limited guidelines on design for dementia, meaning that many of these are theoretical, anecdotal and not definitive. Hence a greater verification to address the less recognised design issues is required. This is intended to ultimately improve quality of life, wellbeing, independence and uphold the dignity of people with dementia living in nursing or residential care homes.
The research design uses a mixed methods approach. A thorough preparation and consideration of ethical issues informed the methodology. The various facets were also trialled and piloted to identify any ethical, technological, methodological, data collection and analysis issues. The protocol was then amended to improve or resolve any of the aforementioned issues. Initially a questionnaire based on leading design recommendations was conducted with home managers. Semi-structured interviews were developed from this and conducted with staff and resident’s next of kin. An evidence-based approach was used to design a study which used ethnographic methods, including a wayfinding task. This followed a repeated measures design which would be used to actively engage residents with dementia in the research. Complementary to the wayfinding task, conversational and semi-structured interviews were used to promote dialogue and direct responses with the person with dementia. In addition to this, Space Syntax methodologies were used to examine the physical properties of the architectural layout. This was then cross-examined with interview responses and data from the wayfinding tasks.
A number of plan typologies were identified and were determined as synonymous with decision point types which needed to be made during the walks. The empirical work enabled the synthesis of environmental features which support wayfinding.
Results indicate that particular environmental features are associated with improved performance on the wayfinding tasks. By enhancing design for dementia, through identifying the attributes, challenges with wayfinding may be overcome and the benefits of the physical environment can be seen to promote wellbeing.
The implications of this work mean that the environmental features which have been highlighted from the project can be used to inform guidelines, thus adding to existing knowledge. Future work would involve the dissemination of this information and the potential for it to be made into design standards or regulations which champion design for dementia. These would increase awareness for designers and stakeholders undertaking new projects, extensions or refurbishments.
A person-centred, evidence-based design was emphasised throughout the project which guaranteed an in-depth study. There were limitations due to the available resources, time and funding. Future research would involve testing the identified environmental features within a specific environment to enable measured observation of improvements.

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OBJECTIVE: To describe the results of revision surgery for complications of trabeculectomy in a case series from an academic glaucoma service. DESIGN: Retrospective case series. PARTICIPANTS: A total of 177 eyes of 167 adult patients who underwent revision of trabeculectomy at the Wilmer Eye Institute between 1994 and 2007. METHODS: Three indications for surgery were identified: hypotony without leak, bleb leak, and bleb dysesthesia. Revision was deemed successful when all of the following were true: the primary indication was eliminated, further intraocular pressure (IOP)-lowering surgery was not required, no major complication occurred, and a new bleb-related problem did not develop. Patients with less than 3 months of follow-up were excluded unless failure occurred earlier. Surgical procedures included variations on excision of thin or leaking conjunctiva with advancement. MAIN OUTCOME MEASURES: Change in IOP, change in visual acuity, need for further IOP-lowering surgery, and complications after bleb revision. RESULTS: Subjects' mean age was 67+/-14 years, 54% were female, and mean follow-up was 2.8+/-2.7 years, with a mean interval from trabeculectomy to revision of 3.5+/-3.7 years. Overall success rate was 63% (112/177), which was slightly higher for leak repair (65%; 64/98) and hypotony (63%; 32/51) than for dysesthesia (57%; 16/28) indications. By Kaplan-Meier analysis, overall cumulative success rates at 1, 2, 5, and 10 years after bleb revision were 80%, 75%, 50%, and 41%, respectively. IOP and visual acuity improved significantly in both hypotony and leak groups (P values ranging from 0.004 to <0.0001). Additional IOP-lowering surgery was required in 9%. In multivariate regression analysis adjusting for age, gender, and number of prior surgeries, patients with glaucoma other than primary open-angle glaucoma were twice as likely to have failed bleb revision. CONCLUSIONS: Surgical bleb revision often provides successful resolution of bleb-related complications. Most patients maintain IOP control without need for further IOP-lowering surgery. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

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Consideramos o problema de controlo óptimo de tempo mínimo para sistemas de controlo mono-entrada e controlo afim num espaço de dimensão finita com condições inicial e final fixas, onde o controlo escalar toma valores num intervalo fechado. Quando aplicamos o método de tiro a este problema, vários obstáculos podem surgir uma vez que a função de tiro não é diferenciável quando o controlo é bang-bang. No caso bang-bang os tempos conjugados são teoricamente bem definidos para este tipo de sistemas de controlo, contudo os algoritmos computacionais directos disponíveis são de difícil aplicação. Por outro lado, no caso suave o conceito teórico e prático de tempos conjugados é bem conhecido, e ferramentas computacionais eficazes estão disponíveis. Propomos um procedimento de regularização para o qual as soluções do problema de tempo mínimo correspondente dependem de um parâmetro real positivo suficientemente pequeno e são definidas por funções suaves em relação à variável tempo, facilitando a aplicação do método de tiro simples. Provamos, sob hipóteses convenientes, a convergência forte das soluções do problema regularizado para a solução do problema inicial, quando o parâmetro real tende para zero. A determinação de tempos conjugados das trajectórias localmente óptimas do problema regularizado enquadra-se na teoria suave conhecida. Provamos, sob hipóteses adequadas, a convergência do primeiro tempo conjugado do problema regularizado para o primeiro tempo conjugado do problema inicial bang-bang, quando o parâmetro real tende para zero. Consequentemente, obtemos um algoritmo eficiente para a computação de tempos conjugados no caso bang-bang.

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The finite length Gold codes used in satellite navigation systems limit their dynamic range, resulting in the introduction of unwanted peaks that can mask out signals of interest. In this paper, a novel cross-correlation interference mitigation technique dealing with this issue is introduced. A brief overview of the multiple access interference problem inherent in satellite navigation systems using the code division multiple access technique is followed by the details of the proposed method. Simulation case studies and analyses of the results detailing weak signal scenarios, carried out entirely using the Global Navigation System Scope, are presented. A comparison of the results is given in the conclusions section along with remarks on the performance of the proposed method and future work to be carried out.

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Super-resolution refers to the process of obtaining a high resolution image from one or more low resolution images. In this work, we present a novel method for the super-resolution problem for the limited case, where only one image of low resolution is given as an input. The proposed method is based on statistical learning for inferring the high frequencies regions which helps to distinguish a high resolution image from a low resolution one. These inferences are obtained from the correlation between regions of low and high resolution that come exclusively from the image to be super-resolved, in term of small neighborhoods. The Markov random fields are used as a model to capture the local statistics of high and low resolution data when they are analyzed at different scales and resolutions. Experimental results show the viability of the method.

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Contemporary thoracic and cardiovascular surgery uses extensive equipment and devices to enable its performance. As the specialties develop and new frontiers are crossed, the technology needs to advance in a parallel fashion. Strokes of genius or problem-solving brain-storming may generate great ideas, but the metamorphosis of an idea into a physical functioning tool requires a lot more than just a thinking process. A modern surgical device is the end-point of a sophisticated, complicated and potentially treacherous route, which incorporates new skills and knowledge acquisition. Processes including technology transfer, commercialisation, corporate and product development, intellectual property and regulatory routes all play pivotal roles in this voyage. Many good ideas may fall by the wayside for a multitude of reasons as they may not be marketable or may be badly marketed. In this article, we attempt to illuminate the components required in the process of surgical innovation, which we believe must remain in the remit of the modern-day thoracic and cardiovascular surgeon.

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Solid state nuclear magnetic resonance (NMR) spectroscopy is a powerful technique for studying structural and dynamical properties of disordered and partially ordered materials, such as glasses, polymers, liquid crystals, and biological materials. In particular, twodimensional( 2D) NMR methods such as ^^C-^^C correlation spectroscopy under the magicangle- spinning (MAS) conditions have been used to measure structural constraints on the secondary structure of proteins and polypeptides. Amyloid fibrils implicated in a broad class of diseases such as Alzheimer's are known to contain a particular repeating structural motif, called a /5-sheet. However, the details of such structures are poorly understood, primarily because the structural constraints extracted from the 2D NMR data in the form of the so-called Ramachandran (backbone torsion) angle distributions, g{^,'4)), are strongly model-dependent. Inverse theory methods are used to extract Ramachandran angle distributions from a set of 2D MAS and constant-time double-quantum-filtered dipolar recoupling (CTDQFD) data. This is a vastly underdetermined problem, and the stability of the inverse mapping is problematic. Tikhonov regularization is a well-known method of improving the stability of the inverse; in this work it is extended to use a new regularization functional based on the Laplacian rather than on the norm of the function itself. In this way, one makes use of the inherently two-dimensional nature of the underlying Ramachandran maps. In addition, a modification of the existing numerical procedure is performed, as appropriate for an underdetermined inverse problem. Stability of the algorithm with respect to the signal-to-noise (S/N) ratio is examined using a simulated data set. The results show excellent convergence to the true angle distribution function g{(j),ii) for the S/N ratio above 100.

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This study examined high school student perceptions of discretion utilized by educators in high school disciplinary proceedings. Using a sample of 6 high school students who had experienced differing levels of formal discipline, the study investigated the discretionary factors that influence an educator's decision making. The study was a generic qualitative study where the primary source of data collection was open-ended interviews to ensure the integrity of the research as a study of student voices and perceptions. Journaling was also employed to record observations and to identify researcher assumptions. The data were analyzed employing aspects of a grounded theory approach. The findings were coded to reveal 5 areas high school students identified in relation to discipline and discretion: punitive discipline versus problem resolution, effective processes, educator discretion, student discretion, and the student-educator relationship. The final discussion highlights the need for a community vision for high school discipline in order to channel discretion and to uphold students' best interests. Restorative justice is proposed as a feasible vision for high school discipline, whereby participants' responses are measured against a restorative paradigm.

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Un atout majeur des organisations consiste en leur capacité à créer et exploiter l’information et les connaissances, capacité déterminée entre autres par les comportements informationnels. Chargés de décisions stratégiques, tactiques et opérationnelles, les cadres intermédiaires sont au cœur du processus de création des connaissances, et leurs comportements informationnels doivent être soutenus par des systèmes d’information. Toutefois, leurs comportements informationnels sont peu documentés. La présente recherche porte sur la modélisation des comportements informationnels de cadres intermédiaires d’une organisation municipale. Plus spécifiquement, elle examine comment ces cadres répondent à leurs besoins d’information courante dans le contexte de leurs activités de gestion, c’est-à-dire dans leur environnement d’utilisation d’information. L’étude répond aux questions de recherche suivantes : (1) Quelles sont les situations problématiques auxquelles font face les cadres intermédiaires municipaux ? (2) Quels sont les besoins informationnels exprimés par les cadres intermédiaires municipaux lors de situations problématiques ? (3) Quelles sont les sources d’information qui soutiennent les comportements informationnels des cadres intermédiaires municipaux ? Cette recherche descriptive s’inscrit dans une approche qualitative. Les 21 cadres intermédiaires ayant participé à l’étude proviennent de deux arrondissements d’une municipalité québécoise fusionnée en 2002. Les modes de collecte de données sont l’entrevue en profondeur en personne et l’observation directe auprès de ces cadres, et la collecte de documentation pertinente. L’incident critique est utilisé comme technique de collecte de données et comme unité d’analyse. Les données recueillies font l’objet d’une analyse de contenu qualitative basée sur la théorisation ancrée. Les résultats indiquent que les rôles de gestion proposés dans les écrits pour les cadres supérieurs s’appliquent aussi aux cadres intermédiaires, bien que le rôle conseil ressorte comme étant particulier à ces derniers. Ceux-ci ont des responsabilités de gestion aux trois niveaux d’intervention opérationnel, tactique et stratégique, bien qu’ils œuvrent davantage au plan tactique. Les situations problématiques dont ils sont chargés s’inscrivent dans l’environnement d’utilisation d’information constitué des composantes suivantes : leurs rôles et responsabilités de gestion et le contexte organisationnel propre à une municipalité en transformation. Les cadres intermédiaires ont eu à traiter davantage de situations nouvelles que récurrentes, caractérisées par des sujets portant principalement sur les ressources matérielles et immobilières ou sur des aspects d’intérêt juridique, réglementaire et normatif. Ils ont surtout manifesté des besoins pour de l’information de nature processuelle et contextuelle. Pour y répondre, ils ont consulté davantage de sources verbales que documentaires, même si le nombre de ces dernières reste élevé, et ont préféré utiliser des sources d’information internes. Au plan théorique, le modèle de comportement informationnel proposé pour les cadres intermédiaires municipaux enrichit les principales composantes du modèle général d’utilisation de l’information (Choo, 1998) et du modèle d’environnement d’utilisation d’information (Taylor, 1986, 1991). L’étude permet aussi de préciser les concepts d’« utilisateur » et d’« utilisation de l’information ». Au plan pratique, la recherche permet d’aider à la conception de systèmes de repérage d’information adaptés aux besoins des cadres intermédiaires municipaux, et aide à évaluer l’apport des systèmes d’information archivistiques à la gestion de la mémoire organisationnelle.