100 research outputs found
GPU cluster for acceleration of scientific and engineering applications in the context of higher education
Many fields of research now rely on High Performance Computing (HPC) systems which can process ever larger datasets, with increasing accuracy and speed. Many
universities now provide a HPC service. Following the trend over the past few years of the worlds fastest supercomputers being accelerated using Graphical Processing Units (GPUs), there is a growing interest in the use of GPUs in Higher Education Institutions.
The characteristics of GPUs make them excellently suited to any task exhibiting a high level of data parallelism. Recent developments in GPU technologies have focused on improving performance and integration in HPC, and for processing data other than display
graphics.
To investigate the benefits such a system could have to the University of Huddersfield, a small GPU cluster has been deployed. The intention behind this thesis is to detail the deployment of the system and to demonstrate, through case studies, the required effort a potential user could expect in order to take advantage of it.
As a result of this work it can be demonstrated that even a modest GPU cluster can be of benefit to the University. The cluster is helping our researchers to analyse complex data using visualisation, and accelerating data processing
High Spatial Resolution Silicon Detectors for Independent Quality Assurance in Motion Adaptive Radiotherapy and Charged Particle Radiotherapy Energy Verification
Accurate empirical modelling of the treatment beam is necessary to ensure accurate delivery of dose to the intended target site. Dose calculations within the treatment planning system (TPS) for Stereotactic Radiosurgery (SRS) and Stereotactic Radiotherapy (SRT) treatment rely upon accurate beam data. Inaccuracies within the empirical measurements will propagate as errors throughout calculated patient dose distributions (Tyler, 2013). The necessary empirical measurements for beam commissioning include: percentage depth dose (PDD), output factor (OF) and beam profiles. Thus, especially for the consideration of the afore mentioned small radiation fields, it is important to ensure the most appropriate detector is chosen to conduct measurements of the treatment beams to achieve the highest possible accuracy in measurement of beam parameters.
Stereotactic Body Radiation Therapy (SBRT) requires precise delineation of the target using modern imaging modalities (MRI, CT etc.), accurate dosimetry to ensure the planned dose is delivered correctly and effective patient immobilisation. For extracranial sites the treatment accuracy is affected by tumour delineation which identifies the extent of the tumour volume and tumour motion resulting from the physical, biological and physiological processes of the human body. Delivery of radiation using highly conformal and small radiation beams presents challenges for dosimetry and quality assurance (Heydarian, 1996), (Das, 2008). To correctly measure dose in a small field an ideal dosimeter must exhibit properties including: small sensitive volume, near water equivalence, minimal beam perturbation and no dose-rate, energy or directional dependence (Pappas, 2008). Also, treatment planning for dose calculation must be conducted using algorithms which can account for the impact of the heterogeneities found in the abdomen and thoracic cavities to ensure calculation of the dose to tissue in regions with complex scattering conditions is accurate (Rubio, 2013)
Risks of using taxation as a public health measure to reduce gambling-related harms
Taxation can be used to increase the prices of and reduce the consumption and harms arising from public health concerns related to tobacco, alcohol, and sugary drinks.1 Gambling is another public health concern,2, 3, 4 and some authors have therefore made the analogous recommendation that gambling-related harms might also be reduced via increases in taxation.2, 5 However, this recommendation neglects the fact that it is largely excessive gambling losses, rather than the act of gambling itself, that produces gambling-related harm.6 Gambling taxes can have negative effects on gambling-related harm via this channel of increasing the losses of gamblers
Framework for the Optimisation of Full Text Queries on Safety Incident Reports
The Railway Industry in Great Britain is on the brink of a seed change in the methods used to carry out safety and risk management. Advances in technology over the past few decades have enabled the collection of varied and detailed information regarding the state of track, vehicles, stations, facilities, and personnel at an ever-increasing scale. As more and more industry processes embrace data driven techniques, the growing volume of data being recorded poses a significant challenge in terms of processing and knowledge extraction.
In these chapters, a case study is made of the Close Call system used by railway organisations in Great Britain. Personnel working on the railway network can make reports to this system by phone, email, and in-app, if they see something they consider to have the potential to cause harm or damage. The near ubiquity of mobile devices allows all staff to make free-text reports at any time which has great potential for the completeness of reporting but comes with some drawbacks. The free-text nature of the reports means that basic processing is inadequate for tasks such as categorisation, knowledge extraction, and reporter feedback, requiring ongoing research into appropriate natural language processing techniques. A variety of techniques have shown promise, but the vast and growing quantity of close call reports being made has meant that computing capacity has limited the number of reports that can be processed, and work so far has often been applied only to a small subset of reports.
The aim of this thesis is to demonstrate that it is possible to process or otherwise transform the close call text to allow existing and future analysis techniques pertaining to this text (and data sources like it) to be applied on a larger scale or smaller timeframe. A novel text indexing technique is presented and evaluated, and when compared to other text indexing and pattern matching methods, it is shown that a significant speed increase is possible over the methods previously used.
Versions of the matching technique described in this work have been presented at the European Safety and Reliability Conference in 2017 and 2019
‘Chances are you’re about to lose’:new independent Australian safer gambling messages tested in UK and USA bettor samples
Current industry-developed safer gambling messages such as ‘Take time to think’ and ‘Gamble responsibly’ have been criticized as ineffective slogans. As a result, Australia has recently introduced seven independently-developed safer gambling messages. The UK Government intends to introduce independently-developed messages from 2024 onwards, and this measure could be similarly appropriate for the US states where sports betting has been legalized and gambling advertising has become pervasive. Given this context, the current study recruited race and sports bettors from the UK and USA to elicit their perceptions of the seven Australian safer gambling messages. Participants (N = 1865) rated on a Likert-scale seven newly introduced messages and two existing ones (‘Take time to think’ and ‘Gamble responsibly’) using seven evaluative statements. Participants also reported their levels of problem gambling severity. For most statements in both jurisdictions, the new messages performed significantly better than the existing ones. Specifically, the new messages were deemed more attention grabbing, applicable on a personal level, helpful to gamblers, and more likely to encourage cutbacks in gambling. The message that included a specific call to action (‘What are you prepared to lose today? Set a deposit limit’) was one of the best performing messages. Interaction effects observed in relation to jurisdiction, age, gender, and problem gambling severity were generally small enough to counteract the argument that different populations might benefit from substantially different messages. These findings add to previous research on the independent design of effective safer gambling messages
IMTeract Tool for Monitoring and Profiling HPC systems and applications
Energy usage of computing equipment is an important consideration and energy inefficiency of computer systems is identified as the single biggest obstacle to advances in computing. Research into low-energy computing products ranges from operating system codes, applications and energy-aware schedulers to cooling systems for data centres. To monitor energy consumption in data and HPC centres it is necessary to develop tools for measuring the energy usage of computer equipment and applications. We have developed power measuring apparatus and a tool, IMTeract, for measuring energy consumption of HPC applications. IMTeract was used for energy usage profiling of HPC clusters running FLUENT and DL-POLY software and a GPU cluster running different implementations of an FFT algorithm. Our experimental results are encouraging and suggest that the IMTeract tool can be used to measure the CPU, Memory, Disk I/O and Network I/O for an application or a process and report on the energy used
Situational features of smartphone betting are linked to sports betting harm:An ecological momentary assessment study
Background and aimsSmartphones extend the situational characteristics of sports betting beyond those available with land-based and computer platforms. This study examined 1) the role of situational features and betting platforms in harmful betting behaviours and short-term betting harm, and 2) whether people with more gambling problems have preferred situational features, engage more in harmful betting behaviours, and experience more severe short-term betting harm.MethodsAn ecological momentary assessment analysed 1,378 betting sessions on sports, esports or daily fantasy sports, reported by 267 respondents (18–29 years; 50.9% male) over 10 weeks.ResultsFactor analysis revealed five situational features of betting sessions: 1) quick, easy access from home, 2) ability to bet anywhere anytime, 3) privacy while betting, 4) greater access to promotions and betting options, and 5) ability to use electronic financial transactions. Regression models underpinned the analyses. Greater short-term betting harm was significantly associated with the ability to bet anywhere anytime, privacy when betting, and greater access to promotions and betting options. Betting sessions when these features were prioritised were more likely to involve impulsive betting, use of betting inducements, and betting with more operators. Respondents with more gambling problems were more likely to prioritise privacy and the ability to bet anywhere anytime; and to bet on in-game events, use promotional inducements, bet with more operators, and report greater betting harm.Discussion and conclusionsCertain situational features of sports betting are empirically associated with engagement and subsequent harm. Only smartphone betting combines all three features associated with betting harm
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