176 research outputs found
Simulation based analysis and an applicaiton to an offshore oil and gas production system of the Natvig measures of component importance in repairable systems
No full textIn the present paper the Natvig measures of component importance for repairable systems, and its extended version are analysed for two three component systems and a bridge system. The measures are also applied to an offshore oil and gas production system. According to the extended version of the Natvig measure a component is important if both by failing it strongly reduces the expected system uptime and by being repaired it strongly reduces the expected system downtime. The results include a study of how different distributions affect the ranking of the components. All numerical results are computed using discrete event simulation. In a companion paper (Huseby, Eide, Isaksen, Natvig and Gåsemyr 2008) the advanced simulation methods needed in these calculations are described
Green ICT : trends and challenges
No full textThe papers included in this issue's monograph aim to show how the ICT sector can improve its own energy use and management or help, by means of applications and services, to efficiently manage resources in other high energy consuming sectors. Achieving a sustainable economy has become an increasingly important issue of concern in the developed world. The ICT sector can play a significant supportive role for future economic growth, by contributing innovative solutions for achieving a productive model based on sustainable developmen
Green ICT: trends and challenges
No full textThe papers included in this issue's monograph aim to show how the ICT sector can improve its own energy use and management or help, by means of applications and services, to efficiently manage resources in other high energy consuming sectors. Achieving a sustainable economy has become an increasingly important issue of concern in the developed world. The ICT sector can play a significant supportive role for future economic growth, by contributing innovative solutions for achieving a productive model based on sustainable developmen
Presentation : Green ICT : The Information Society’s Commitment for Environmental Sustainability
No full textPresentation of the Monograph "Green ICT:trends and challenges
TIC verdes : El compromiso de la Sociedad de la Información con un desarrollo sostenible. Presentación
No full textVoice Compression and Communications: Principles and Applications for Fixes and Wireless Channels
No full textUp-to-date, expert coverage of topics in wireless voice communications Voice communication is the most important facet of mobile radio service. Even when the predicted surge of wireless data and Internet services becomes a reality, voice will remain the most natural means of human communication. Voice Compression and Communications details issues in wireless voice communications and treats compression, channel coding, and wireless transmission as a joint subject. Part I covers background material, whereas Part II provides detailed information on both proprietary and standardized analysis-by-synthesis codecs, including the speech codecs of virtually all existing wireline-based and wireless systems. Parts III and IV discuss mainly research-based wideband, audio, as well as very low-rate schemes likely to find their way into future standards. Voice Compression and Communications describes fundamental concepts in a non-mathematical way early in the book for those with only a background knowledge of signal processing and communications. More advanced readers will find detailed discussions of theoretical principles, future concepts, and solutions to various specific wireless voice communications problems
Harry L. Justice v. Ralph A. Natvig
No full textSupreme Court of Virginiahttps://scholarlycommons.law.wlu.edu/va-supreme-court-records-vol238/1023/thumbnail.jp
Pain-related fear and functional recovery in sciatica: results from a 2-year observational study
No full textAJ Haugen,1 L Grøvle,1 JI Brox,2 B Natvig,3 M Grotle4 1Department of Rheumatology, Østfold Hospital Trust, Grålum, 2Department of Physical Medicine and Rehabilitation, Division for Neuroscience, Oslo University Hospital, 3Department of General Practice, Institute of Health and Society, University of Oslo, 4FORMI (Communication Unit for Musculoskeletal Disorders), Division of Neuroscience, Oslo University Hospital, Oslo, Norway Objectives: The purpose of this study was to explore the associations between pain-related fear, pain disability, and self-perceived recovery among patients with sciatica and disk herniation followed up for 2 years.Patients and methods: Pain-related fear was measured by the Tampa Scale for Kinesiophobia (TSK) and the Fear-Avoidance Beliefs Questionnaire-Physical Activity (FABQ-PA) subscale. Disability was measured by the Maine–Seattle Back Questionnaire. At 2 years, patients reported their sciatica/back problem on a global change scale ranging from completely gone to much worse. No specific interventions regarding pain-related fear were provided.Results: Complete data were obtained for 372 patients. During follow-up, most patients improved. In those who at 2 years were fully recovered (n=66), pain-related fear decreased substantially. In those who did not improve (n=50), pain-related fear remained high. Baseline levels of pain-related fear did not differ significantly between those who were fully recovered and the rest of the cohort. In the total cohort, the correlation coefficients between the 0–2-year change in disability and the changes in the TSK and the FABQ-PA were 0.33 and 0.38, respectively. In the adjusted regression models, the 0–2-year change in pain-related disability explained 15% of the variance in the change in both questionnaires.Conclusion: Pain-related fear decreased substantially in patients who recovered from sciatica and remained high in those who did not improve. Generally, the TSK and the FABQ-PA yielded similar results. To our knowledge, this is the first study that has assessed pain-related fear in patients who recover from sciatica. Keywords: kinesiophobia, fear-avoidance, recover
Energy Efficient Computing on Multi-core Processors: Vectorization and Compression Techniques
No full textOver the past few years, energy consumption has become the main limiting factor for computing in general. This has led CPU vendors to aggressively promote parallel computing using multiple cores without significantly increasing the thermal design power of the processor. However, achieving maximum performance and energy efficiency from the available resources on the multi-core and many-core platforms mandates efficient exploitation of the existing and emerging architectural features at the application level.
This thesis presents the study of some of the existing and emerging technologies in order to identify the potential of exploiting these technologies in achieving high performance and energy efficiency for a set of Smart Grid applications on Intel multi-core and many-core platforms.
The first part of this thesis explores the energy efficiency impact of different multi-core programming techniques for a selected set of benchmarks and smart grid applications on Intel SandyBridge and Haswell multi-core processors. These techniques include different parallelism techniques such as thread-level parallelism using OpenMP, task-based parallelism using OmpSs, data parallelism using SIMD (Single Instruction Multiple Data) instruction sets, code optimizations and use of different existing optimized math libraries. In our initial case studies, SIMD vectorization is proven very effective in providing both high performance and energy efficiency.
Though the SIMD vectorization is proven very effective, it can also exert pressure on the available memory bandwidth for some applications like Powel Time-Series Kernel, causing under-utilization of the computing resources and thus energy inefficient executions. In the second part of this research, we investigate the opportunities of improving the performance of SIMD vectorization for memory-bound applications using SIMD data compression, SIMD software prefetching, SIMD shuffling, code-blocking and other code transformation techniques. The key idea is to reduce the data movement across memory hierarchy by using the idle CPU time. We show that integration of data compression is feasible on the Intel multicore platforms, as long as we can do it in a reasonable time. We present a comprehensive discussion on the SIMD compression techniques and the code transformations required for achieving efficient SIMD computations for memory/cache bound applications using Powel time series kernel as a demonstrator application.
Finally, we perform feasibility study of SIMD optimization and compression techniques across other application domains using k-means clustering algorithm and full-search motion estimation algorithm. We also extended our experiments on Intel many-core architecture using Intel Xeon Phi coprocessor
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