14 resultados para 280403 Logics and Meanings of Programs
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
Moisture is a well documented, and crucial, control on the nature of stone decay. The term time of wetness has frequently been adopted to describe how long a stone block is wet, with a view to understanding the impact of this on decay processes. Although this term has proved conceptually useful, it has been used in different ways, by different groups to mean mean quite different things. For example, the time of wetness for a stone block surface (the traditional understanding) may be quite different from that of a block interior, controlled by the different dynamics of wetting and drying in those zones. Thus, surface wetting will occur regularly (sometimes swiftly followed by drying, depending on the time of year), with block interior wetting requiring the accumulation of surface moisture to penetrate to depth (more likely in autumn and winter months), and drying out much more slowly. This relatively new but important perspective, framed in the context of climate change, is crucial to understanding the length of time stone may remain damp at depth following a period of prolonged precipitation. The nature and speed of drying is also relevant in quantifying time of wetness of both surfaces and the interior of building stones.
These ideas related to time of wetness have implications for decay processes, specifically how a prolonged time of deep wetness may re-focus the emphasis of salt weathering in natural building stones toward chemical action. Literature on chemical change is discussed, suggesting that chemical change occurring during periods of prolonged wetness is likely to be significant in itself, with implications for weakening the stone (in terms of, for example, cement dissolution or grain boundary weakening) and exacerbating physical damage from salt crystallisation when blocks finally dry out.
Resumo:
The inherent difficulty of thread-based shared-memory programming has recently motivated research in high-level, task-parallel programming models. Recent advances of Task-Parallel models add implicit synchronization, where the system automatically detects and satisfies data dependencies among spawned tasks. However, dynamic dependence analysis incurs significant runtime overheads, because the runtime must track task resources and use this information to schedule tasks while avoiding conflicts and races.
We present SCOOP, a compiler that effectively integrates static and dynamic analysis in code generation. SCOOP combines context-sensitive points-to, control-flow, escape, and effect analyses to remove redundant dependence checks at runtime. Our static analysis can work in combination with existing dynamic analyses and task-parallel runtimes that use annotations to specify tasks and their memory footprints. We use our static dependence analysis to detect non-conflicting tasks and an existing dynamic analysis to handle the remaining dependencies. We evaluate the resulting hybrid dependence analysis on a set of task-parallel programs.
Resumo:
Abstract: First exposure to human cadaver dissection has the potential to be an actual stressor which can cause psychological trauma. This study examines the relationship between anatomy students’ experience of this potential stressor and various psychological and personal factors. Questionnaires measuring emotional reactions to cadaver dissection, coping strategies, personality and attitudes to death were administered to anatomy students at two medical schools immediately after their first exposure to human cadaver dissection. Emotional reactions to recalling this experience were assessed 4 months later. Data on these variables were obtained from 141 students. Students found the experience mostly challenging and, on average, did not report serious emotional difficulties. However, a minority of students (10/141) experienced serious adverse consequences. It is possible that the typical student who undertakes an anatomy course is already psychologically prepared for such transactions. However, low cost desensitization programs could be made available for the minority of individuals who may experience adverse reactions in this situation.
Resumo:
Context: Shared care models integrating family physician services with interdisciplinary palliative care specialist teams are critical to improve access to quality palliative home care and address multiple domains of end-of-life issues and needs. Objectives: To examine the impact of a shared care pilot program on the primary outcomes of symptom severity and emotional distress (patient and family separately) over time and, secondarily, the concordance between patient preferences and place of death. Methods: An inception cohort of patients (n = 95) with advanced, progressive disease, expected to die within six months, were recruited from three rural family physician group practices (21 physicians) and followed prospectively until death or pilot end. Serial measurement of symptoms, emotional distress (patient and family), and preferences for place of death was performed, with analysis of changes in distress outcomes assessed using t-tests and general linear models. Results: Symptoms trended toward improvement, with a significant reduction in anxiety from baseline to 14 days noted. Symptom and emotional distress were maintained below high severity (7-10), and a high rate of home death compared with population norms was observed. Conclusion: Future controlled studies are needed to examine outcomes for shared care models with comparison groups. Shared care models build on family physician capacity and as such are promising in the development of palliative home care programs to improve access to quality palliative home care and foster health system integration. © 2011 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.
Resumo:
This paper critically interrogates how borders are produced by scientists, engineers and security experts in advance of the actual deployment of technical devices they develop. This paper explores the prior stages of translation and decision-making as a socio-technical device is conceived and developed. Drawing on in-depth interviews, observations and ethnographic research of the EU-funded Handhold project (consisting of nine teams in five countries), it explores how assumptions about the way security technologies will and should perform at the border shape the way that scientists, engineers, and security experts develop a portable, integrated device to detect CBRNE threats at borders. In disaggregating the moments of sovereign decision making across multiple sites and times, this paper questions the supposed linearity of how science comes out of and feeds back into the world of border security. An interrogation of competing assumptions and understandings of security threats and needs, of competing logics of innovation and pragmatism, of the demands of differentiated temporalities in detection and interrogation, and of the presumed capacities, behaviours, and needs of phantasmic competitors and end-users reveals a complex, circulating and co-constitutive process of device development that laboratises the border itself. We trace how sovereign decisions are enacted as assemblages in the antecedent register of device development itself through the everyday decisions of researchers in the laboratory, and the material components of the Handhold device itself.
Resumo:
In this ‘research project’ case study, we provide an empirical example of how quantitative and qualitative methods were combined within a single study and discuss some of the strengths and weaknesses of our combined methodology which included questionnaires, photo-prompts and focus-group interviews. Our intention in using mixed methods was to enhance understandings of the meanings of space, place and territory on the everyday lives of young people growing up in Belfast. How do young people negotiate space in politically divided cities such as Belfast? Is territory important, and if so, why is it important? How do we construct an appropriate and relevant study design that can not only describe, but explain what place, space and territory mean to young people, and more importantly, how it impacts on their everyday lives? How useful is it to apply a mixed-methods approach to finding answers to these questions? We explain why and how we used a mixed-methods approach and illuminate some of the issues we encountered. We demonstrate how mixed methods can provide not just complementary but also new insights into the topic under investigation. We hope that the case study encourages you to experiment, or at least consider, the potential of using mixed methods.
Resumo:
OBJECTIVE: To study spectacle wear among rural Chinese children. METHODS: Visual acuity, refraction, spectacle wear, and visual function were measured. RESULTS: Among 1892 subjects (84.7% of the sample), the mean (SD) age was 14.7 (0.8) years. Among 948 children (50.1%) potentially benefiting from spectacle wear, 368 (38.8%) did not own them. Among 580 children owning spectacles, 17.9% did not wear them at school. Among 476 children wearing spectacles, 25.0% had prescriptions that could not improve their visual acuity to better than 6/12. Therefore, 62.3% (591 of 948) of children needing spectacles did not benefit from appropriate correction. Children not owning and not wearing spectacles had better self-reported visual function but worse visual acuity at initial examination than children wearing spectacles and had a mean (SD) refractive error of -2.06 (1.15) diopter (D) and -2.78 (1.32) D, respectively. Girls (P < .001) and older children (P = .03) were more likely to be wearing their spectacles. A common reason for nonwear (17.0%) was the belief that spectacles weaken the eyes. Among children without spectacles, 79.3% said their families would pay for them (mean, US $15). CONCLUSIONS: Although half of the children could benefit from spectacle wear, 62.3% were not wearing appropriate correction. These children have significant uncorrected refractive errors. There is potential to support programs through spectacle sales.
Resumo:
The focus of this work is to develop the knowledge of prediction of the physical and chemical properties of processed linear low density polyethylene (LLDPE)/graphene nanoplatelets composites. Composites made from LLDPE reinforced with 1, 2, 4, 6, 8, and 10 wt% grade C graphene nanoplatelets (C-GNP) were processed in a twin screw extruder with three different screw speeds and feeder speeds (50, 100, and 150 rpm). These applied conditions are used to optimize the following properties: thermal conductivity, crystallization temperature, degradation temperature, and tensile strength while prediction of these properties was done through artificial neural network (ANN). The three first properties increased with increase in both screw speed and C-GNP content. The tensile strength reached a maximum value at 4 wt% C-GNP and a speed of 150 rpm as this represented the optimum condition for the stress transfer through the amorphous chains of the matrix to the C-GNP. ANN can be confidently used as a tool to predict the above material properties before investing in development programs and actual manufacturing, thus significantly saving money, time, and effort.
Resumo:
Objectives: To explore the content and methodology of predoctoral Geriatric Dentistry teaching amongst European dental schools.
Methods: The study was conducted by the European College of Gerodontology (ECG) Education Committee. Αn electronic questionnaire has been developed with close and open-ended items, including information on the prevalence and institutional anchorage of Gerodontology programs, the educators, the content and the methodology of teaching. An electronic mail, including a hyperlink to the questionnaire, was sent to 216 dental schools in 39 European countries (Winter/ Spring 2016). The Deans were asked to either answer themselves, or forward the link to faculty members with knowledge on Gerodontology teaching at their respective schools. Repeated reminders or telephone calls were used for non-respondents and personal networks were exploited to identify potential contact persons.
Results: Until August 2016, 121 dental schools from 29 countries responded to the survey (response rate 56%, EU response rate: 60%). Gerodontology was included in the predoctoral curricula of 86% of the respondents and was compulsory in 68%. The course was mainly offered in senior students and was interdisciplinary in 30% of the schools, delivered mainly by dentists (79%), physicians (21%), psychologists (10%), and nurses (5%). It was conducted as an independent lecture series in 40% of the schools and a course director was assigned in 44% of the respondents. When embedded in other disciplines, these were mainly Prosthodontics (31%). The content included a large number of items, such as epidemiology of oral health, medical problems in old age, prosthodontic management, xerostomia, and caries risk assessment. Lectures were the most common teaching format (69%), followed by small group seminars (27%). The most common types of educational material used were scientific articles (48%), printed textbooks (44%), lecture notes (40%) and e-learning material (21%). Clinical training was offered by 64% of the respondents, within the dental school clinics (49%) and/or in outreach locations (40%).
Conclusion: Amongst the respondent European dental schools (66%) there is an increasing number that teach Gerodontology at a pre-doctoral level with significant variations in content and methodology. Official guidelines and the dissemination of the ECG pre-doctoral curriculum guidelines might help to increase the prevalence and improve the status of Gerodontology teaching in Europe.