1,810 research outputs found

    A Domain Specific Approach to High Performance Heterogeneous Computing

    Full text link
    Users of heterogeneous computing systems face two problems: firstly, in understanding the trade-off relationships between the observable characteristics of their applications, such as latency and quality of the result, and secondly, how to exploit knowledge of these characteristics to allocate work to distributed computing platforms efficiently. A domain specific approach addresses both of these problems. By considering a subset of operations or functions, models of the observable characteristics or domain metrics may be formulated in advance, and populated at run-time for task instances. These metric models can then be used to express the allocation of work as a constrained integer program, which can be solved using heuristics, machine learning or Mixed Integer Linear Programming (MILP) frameworks. These claims are illustrated using the example domain of derivatives pricing in computational finance, with the domain metrics of workload latency or makespan and pricing accuracy. For a large, varied workload of 128 Black-Scholes and Heston model-based option pricing tasks, running upon a diverse array of 16 Multicore CPUs, GPUs and FPGAs platforms, predictions made by models of both the makespan and accuracy are generally within 10% of the run-time performance. When these models are used as inputs to machine learning and MILP-based workload allocation approaches, a latency improvement of up to 24 and 270 times over the heuristic approach is seen.Comment: 14 pages, preprint draft, minor revisio

    Seeing Shapes in Clouds: On the Performance-Cost trade-off for Heterogeneous Infrastructure-as-a-Service

    Full text link
    In the near future FPGAs will be available by the hour, however this new Infrastructure as a Service (IaaS) usage mode presents both an opportunity and a challenge: The opportunity is that programmers can potentially trade resources for performance on a much larger scale, for much shorter periods of time than before. The challenge is in finding and traversing the trade-off for heterogeneous IaaS that guarantees increased resources result in the greatest possible increased performance. Such a trade-off is Pareto optimal. The Pareto optimal trade-off for clusters of heterogeneous resources can be found by solving multiple, multi-objective optimisation problems, resulting in an optimal allocation of tasks to the available platforms. Solving these optimisation programs can be done using simple heuristic approaches or formal Mixed Integer Linear Programming (MILP) techniques. When pricing 128 financial options using a Monte Carlo algorithm upon a heterogeneous cluster of Multicore CPU, GPU and FPGA platforms, the MILP approach produces a trade-off that is up to 110% faster than a heuristic approach, and over 50% cheaper. These results suggest that high quality performance-resource trade-offs of heterogeneous IaaS are best realised through a formal optimisation approach.Comment: Presented at Second International Workshop on FPGAs for Software Programmers (FSP 2015) (arXiv:1508.06320

    A High-Performance Triple Patterning Layout Decomposer with Balanced Density

    Full text link
    Triple patterning lithography (TPL) has received more and more attentions from industry as one of the leading candidate for 14nm/11nm nodes. In this paper, we propose a high performance layout decomposer for TPL. Density balancing is seamlessly integrated into all key steps in our TPL layout decomposition, including density-balanced semi-definite programming (SDP), density-based mapping, and density-balanced graph simplification. Our new TPL decomposer can obtain high performance even compared to previous state-of-the-art layout decomposers which are not balanced-density aware, e.g., by Yu et al. (ICCAD'11), Fang et al. (DAC'12), and Kuang et al. (DAC'13). Furthermore, the balanced-density version of our decomposer can provide more balanced density which leads to less edge placement error (EPE), while the conflict and stitch numbers are still very comparable to our non-balanced-density baseline

    Strangers sharing space and lives : a qualitative study of the attitudes of single elderly persons living in shared accommodation in Hong Kong public housing estates = 「同居共住:長者對合住公共房屋的意見調查硏究」硏究報告

    Full text link
    In response to the perceived housing needs of single elderly people, the Housing for Senior Citizens Scheme has been developed by the Hong Kong Housing Authority since the mid-1980s to provide shared housing for unrelated elderly people. Under this scheme, they live together in an apartment unit with individual bedrooms, but sharing certain facilities. This group is fairly numerous and, in Hong Kong in 1998, there were about 110,000 elderly people living alone for various reasons,among whom 34,000 were tenants in public housing estates. Despite some advantages, shared living for any age group can however lead to potential problems. Using qualitative methodologies including focus groups and in-depth interviews, the research attempted to gain insights into the views of residents on the design and management of HSC projects, and their aspirations. Nine of the 38 HSC projects operating in 32 Hong Kong public housing estates in mid-1998 were studied. A total of 69 elderly participants (78% female, 22% male) attended the nine focus groups, each comprising 6 to 12 residents. Participants\u27 ages ranged from 62 to 90 years and their length of residence in an HSC from three months to 11 years. To residents, positive features of the HSC projects included the provision of shelter in an elderly person\u27s later life, the care and attention of wardens and the installation of emergency alarms. Design and facility improvements in the newer housing estates appeared to serve better the needs of the residents, with enhanced privacy and reduction in shared facilities. However, older blocks still suffered from problems of insufficient maintenance and repair, and perceived high charges. Most residents appeared to have tried hard to adjust to group life but would prefer to have their own kitchen and bathroom. Conflicts sometimes arose from personality clashes, different cleaning and living habits, shared facilities and bills for water and repairs. Nevertheless, there were some residents who enjoyed the informal caring relationships and the feeling of security. Another important feature found with respect to the elderly respondents was their low self-esteem and strong sense of powerlessness derived from their sharing of accommodation. Poor family relationships and previous living arrangements were also evident. The research suggests that integration of a caring role into housing provision is increasingly important. Autonomy in housing choice and in the management of life styles are also crucial given the diversity of personalities, needs and demands of the elderly population. The group living model should not be assumed to be a panacea for all single older persons in housing need

    The international diffusion of expatriate dual citizenship

    Get PDF
    While the global increase of expatriate dual citizenship acceptance over the past decades has been widely observed, the temporal and spatial contexts of this trend have remained understudied. Based on a novel data set of expatriate dual citizenship policies worldwide since 1960, we find that dual citizenship toleration has increased in the last half century from one-third to three-quarter of states globally. We argue that these domestic policy changes should be understood in light of normative pressure in a world where restrictions on individual choice in citizenship status are increasingly contested and where liberalisation is reinforced through interdependence and diaspora politics. We apply Cox proportional hazard models to examine dual citizenship liberalisation and find that states are more likely to move to a tolerant policy if neighbouring states have done so and that they tend to do so in conjunction with extending voting rights to citizens residing abroad and receiving remittances from abroad. Contrary to other studies, we do not observe significant variation by regime type.publishedVersio

    From Ise to the World in a Time of Pandemic

    Get PDF
    A collection of essays on COVID-19 by scholars from around the world who shared a common experience in Japan in the early stages of the pandemic, and then communicated from their respective countries as the disease spread around the world. Written in multiple styles and with diverse perspectives, these essays provide insight into the similarities and differences, and the equalizing and dis-equalizing aspects of the world’s response to the pandemic

    BRCA1-IRIS Overexpression Promotes Formation of Aggressive Breast Cancers

    Get PDF
    Introduction: Women with HER2 + or triple negative/basal-like (TN/BL) breast cancers succumb to their cancer rapidly due, in part to acquired Herceptin resistance and lack of TN/BL-targeted therapies. BRCA1-IRIS is a recently discovered, 1399 residue, BRCA1 locus alternative product, which while sharing 1365 residues with the full-length product of this tumor suppressor gene, BRCA1/p220, it has oncoprotein-like properties. Here, we examine whether BRCA1-IRIS is a valuable treatment target for HER2 + and/or TN/BL tumors

    Effect Of Combined Aerobic And Resistance Training On HPA Axis Reactivity In HIV+ Women Undergoing Treatment For Substance Abuse

    Get PDF
    Substance abuse and infection with human immunodeficiency virus (HIV) are chronic stressors that affect hypothalamic-pituitary-adrenal (HPA) axis function. The purpose of this study was to investigate the effect of combined aerobic and resistance training on HPA axis reactivity in women with HIV undergoing treatment for substance abuse. Sixteen women (mean ± SD; 41 ± 9 years, 164 ± 6 cm, 78.1 ± 17.1 kg, 36 ± 10 % body fat) infected with HIV and enrolled in an intensive 60-day in-patient substance addiction/abuse treatment program were recruited shortly after admission to the treatment facility. Participants were assigned to one of two groups using randomization: (1) supervised combined aerobic and resistance exercise sessions 3 times per week (EX) for six weeks or (2) no exercise training (Control) for six weeks. Before (PRE) and after (POST) the 6-week period participants completed a 10-min public speaking task (Trier Social Stress Test). Saliva samples were obtained before (baseline), immediately after, and every 10 min for 50 min after the task. Saliva samples were analyzed for cortisol. HPA axis reactivity was determined as the difference between the highest values after the test minus the baseline value. HPA axis reactivity did not differ between groups at PRE (EX: 1.9 ± 2.0 nmol•L-1; Control: 1.1 ± 2.7 nmol•L-1) or POST (EX: 1.7 ± 2.1 nmol•L-1; Control: 0.0 ± 1.3 nmol•L-1). Similarly no differences were found between PRE and POST although the reactivity for the Control group appeared to be reduced at POST. HIV+ women in early recovery from substance abuse appear to display blunted HPA axis reactivity. A combined aerobic and resistance training intervention did not affect this reactivity; although, the exercise intervention might have prevented a further decline in reactivity
    corecore