Run-time parallelization and scheduling of loops

Run time methods are studied to automatically parallelize and schedule iterations of a do loop in certain cases, where compile-time information is inadequate. The methods presented involve execution time preprocessing of the loop. At compile-time, these methods set up the framework for performing a loop dependency analysis. At run time, wave fronts of concurrently executable loop iterations are identified. Using this wavefront information, loop iterations are reordered for increased parallelism. Symbolic transformation rules are used to produce: inspector procedures that perform execution time preprocessing and executors or transformed versions of source code loop structures. These transformed loop structures carry out the calculations planned in the inspector procedures. Performance results are presented from experiments conducted on the Encore Multimax. These results illustrate that run time reordering of loop indices can have a significant impact on performance. Furthermore, the overheads associated with this type of reordering are amortized when the loop is executed several times with the same dependency structure

Run-time scheduling and execution of loops on message passing machines

Sparse system solvers and general purpose codes for solving partial differential equations are examples of the many types of problems whose irregularity can result in poor performance on distributed memory machines. Often, the data structures used in these problems are very flexible. Crucial details concerning loop dependences are encoded in these structures rather than being explicitly represented in the program. Good methods for parallelizing and partitioning these types of problems require assignment of computations in rather arbitrary ways. Naive implementations of programs on distributed memory machines requiring general loop partitions can be extremely inefficient. Instead, the scheduling mechanism needs to capture the data reference patterns of the loops in order to partition the problem. First, the indices assigned to each processor must be locally numbered. Next, it is necessary to precompute what information is needed by each processor at various points in the computation. The precomputed information is then used to generate an execution template designed to carry out the computation, communication, and partitioning of data, in an optimized manner. The design is presented for a general preprocessor and schedule executer, the structures of which do not vary, even though the details of the computation and of the type of information are problem dependent

Parallelization of irregularly coupled regular meshes

Regular meshes are frequently used for modeling physical phenomena on both serial and parallel computers. One advantage of regular meshes is that efficient discretization schemes can be implemented in a straight forward manner. However, geometrically-complex objects, such as aircraft, cannot be easily described using a single regular mesh. Multiple interacting regular meshes are frequently used to describe complex geometries. Each mesh models a subregion of the physical domain. The meshes, or subdomains, can be processed in parallel, with periodic updates carried out to move information between the coupled meshes. In many cases, there are a relatively small number (one to a few dozen) subdomains, so that each subdomain may also be partitioned among several processors. We outline a composite run-time/compile-time approach for supporting these problems efficiently on distributed-memory machines. These methods are described in the context of a multiblock fluid dynamics problem developed at LaRC

愛知大學文學論叢第６５輯 表紙

For nation-states, the contexts for developing and implementing policy have become more complex and demanding. Yet policy studies have not fully responded to the challenges and opportunities represented by these developments. Governance literature has drawn attention to a globalising and network-based policy world, but politics and the role of the state have been de-emphasised. This book addresses this imbalance by reconsidering traditional policy-analytic concepts, and re-developing and extending new ones, in a melded approach defined as systemic institutionalism. This links policy with governance and the state and suggests how real-world issues might be substantively addressed

Ethical Issues in the New Digital Era: The Case of Assisting Driving

Mobility is associated with driving a vehicle. Age-related declines in the abilities of older persons present certain obstacles to safe driving. The negative effects of driving cessation on older adults’ physical, mental, cognitive, and social functioning are well reported. Automated driving solutions represent a potential solution to promoting driver persistence and the management of fitness to drive issues in older adults. Technology innovation influences societal values and raises ethical questions. The advancement of new driving solutions raises overarching questions in relation to the values of society and how we design technology (a) to promote positive values around ageing, (b) to enhance ageing experience, (c) to protect human rights, (d) to ensure human benefit and (e) to prioritise human well-being. To this end, this chapter reviews the relevant ethical considerations in relation to assisted driving solutions. Further, it presents a new ethically aligned system concept for assisted driving. It is argued that human benefit, well-being and respect for human identity and rights are important goals for new automated driving technologies. Enabling driver persistence is an issue for all of society and not just older adult

Driver Persistence, Safety and Older Adult Self-efficacy: Addressing Driving Challenges Using Innovative Multimodal Communication Concepts

New assisted driving technology provides a solution to enabling driver persistence while also addressing older adult fitness to drive issues. The proposed driver assistance system follows a detailed literature review, an analysis of secondary data, and the specification of a solution using human machine interaction (HMI) design methods. Overall, the assisted driving concept follows from a principled/ethical perspective in relation to promoting self-efficacy and enablement for older adults. The system is conceptualized as a supportive friend or ‘co-pilot’. It is argued that the use of new car-based sensors, along with machine learning intelligence and novel multimodal HMI communication methods will enable driver persistence while also promoting older adult self-efficacy and positive ageing

Habitual physical activity and cardiometabolic risk factors in adults with cerebral palsy

2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/3.0/).This article has been made available through the Brunel Open Access Publishing Fund.Adults with cerebral palsy (CP) are known to participate in reduced levels of total physical activity. There is no information available however, regarding levels of moderate-to-vigorous physical activity (MVPA) in this population. Reduced participation in MVPA is associated with several cardiometabolic risk factors. The purpose of this study was firstly to compare levels of sedentary, light, MVPA and total activity in adults with CP to adults without CP. Secondly, the objective was to investigate the association between physical activity components, sedentary behavior and cardiometabolic risk factors in adults with CP. Adults with CP (n = 41) age 18–62 yr (mean ± SD = 36.5 ± 12.5 yr), classified in Gross Motor Function Classification System level I (n = 13), II (n = 18) and III (n = 10) participated in this study. Physical activity was measured by accelerometry in adults with CP and in age- and sex-matched adults without CP over 7 days. Anthropometric indicators of obesity, blood pressure and several biomarkers of cardiometabolic disease were also measured in adults with CP. Adults with CP spent less time in light, moderate, vigorous and total activity, and more time in sedentary activity than adults without CP (p < 0.01 for all). Moderate physical activity was associated with waist-height ratio when adjusted for age and sex (β = −0.314, p < 0.05). When further adjustment was made for total activity, moderate activity was associated with waist-height ratio (β = −0.538, p < 0.05), waist circumference (β = −0.518, p < 0.05), systolic blood pressure (β = −0.592, p < 0.05) and diastolic blood pressure (β = −0.636, p < 0.05). Sedentary activity was not associated with any risk factor. The findings provide evidence that relatively young adults with CP participate in reduced levels of MVPA and spend increased time in sedentary behavior, potentially increasing their risk of developing cardiometabolic disease

Selective observation of the disordered import signal of a globular protein by in-cell NMR: The example of frataxins

We have exploited the capability of in-cell NMR to selectively observe flexible regions within folded proteins to carry out a comparative study of two members of the highly conserved frataxin family which are found both in prokaryotes and in eukaryotes. They all contain a globular domain which shares more than 50% identity, which in eukaryotes is preceded by an N-terminal tail containing the mitochondrial import signal. We demonstrate that the NMR spectrum of the bacterial ortholog CyaY cannot be observed in the homologous E. coli system, although it becomes fully observable as soon as the cells are lysed. This behavior has been observed for several other compact globular proteins as seems to be the rule rather than the exception. The NMR spectrum of the yeast ortholog Yfh1 contains instead visible signals from the protein. We demonstrate that they correspond to the flexible N-terminal tail indicating that this is flexible and unfolded. This flexibility of the N-terminus agrees with previous studies of human frataxin, despite the extensive sequence diversity of this region in the two proteins. Interestingly, the residues that we observe in in-cell experiments are not visible in the crystal structure of a Yfh1 mutant designed to destabilize the first helix. More importantly, our results show that, in cell, the protein is predominantly present not as an aggregate but as a monomeric species