Evaluating Asymmetric Multicore Systems-on-Chip using Iso-Metrics

The end of Dennard scaling has pushed power consumption into a first order concern for current systems, on par with performance. As a result, near-threshold voltage computing (NTVC) has been proposed as a potential means to tackle the limited cooling capacity of CMOS technology. Hardware operating in NTV consumes significantly less power, at the cost of lower frequency, and thus reduced performance, as well as increased error rates. In this paper, we investigate if a low-power systems-on-chip, consisting of ARM's asymmetric big.LITTLE technology, can be an alternative to conventional high performance multicore processors in terms of power/energy in an unreliable scenario. For our study, we use the Conjugate Gradient solver, an algorithm representative of the computations performed by a large range of scientific and engineering codes.Comment: Presented at HiPEAC EEHCO '15, 6 page

The one-loop gluon amplitude for heavy-quark production at NNLO

We compute the one-loop QCD amplitude for the process gg-->Q\bar{Q} in dimensional regularization through order \epsilon^2 in the dimensional regulator and for arbitrary quark mass values. This result is an ingredient of the NNLO cross-section for heavy quark production at hadron colliders. The calculation is performed in conventional dimensional regularization, using well known reduction techniques as well as a method based on recent ideas for the functional form of one-loop integrands in four dimensions.Comment: 27 pages, 3 figure

When sitting becomes sport: life stories in sitting volleyball

Results of recent studies support a growing literature which indicates that exercise and physical activity are associated with better quality of life and health outcomes. The purpose of the present qualitative study is to gain a deeper insight into how sitting volleyball players perceive the impact of the sport on their lives. So far, the research in the field of disability and sport has tended to focus on ideological approaches rather than empiricism. Thus, the present study explores how the participants experience their disability and their involvement in sport. The research was conducted with a group of 5 male sitting volleyball players (aged 32 to 61 years old) in Athens, Greece. Data were collected primarily through audio-recorded, semi-structured in-depth interviews and enriched with participant observation field notes. Data was analysed following an Interpretative Phenomenological Analysis (IPA) as the aim of the research was to capture the players’ perceptions of their participation in sitting volleyball

Inferring the neutron star equation of state from binary inspiral waveforms

The properties of neutron star matter above nuclear density are not precisely known. Gravitational waves emitted from binary neutron stars during their late stages of inspiral and merger contain imprints of the neutron-star equation of state. Measuring departures from the point-particle limit of the late inspiral waveform allows one to measure properties of the equation of state via gravitational wave observations. This and a companion talk by J. S. Read reports a comparison of numerical waveforms from simulations of inspiraling neutron-star binaries, computed for equations of state with varying stiffness. We calculate the signal strength of the difference between waveforms for various commissioned and proposed interferometric gravitational wave detectors and show that observations at frequencies around 1 kHz will be able to measure a compactness parameter and constrain the possible neutron-star equations of state.Comment: Talk given at the 12th Marcel Grossman Meeting, Paris, France, 12-18 Jul 200

Constructing a protocol for the evaluation of residents' competency with office hysteroscopy

There is an increasing need for clinician self-evaluation. The need becomes bigger when it comes to assess residents in operative procedures; office hysteroscopy in its current form is one of the best examples to teach and to assess them. We propose a simple protocol for the evaluation of residents in office hysteroscopy that can be used as a platform for future improvement. This will improve their learning experience and ensure that they do not miss any steps of the procedure. As each task is outlined on the evaluation checklist, it is easier to objectively demonstrate the strengths and deficiencies of each one with respect to the given procedure. This can be the basis for application of extra attention and highlights the areas in which each individual needs to improve. The advantage of recording parameters, such as duration of the procedure and pain scores, is that they can serve as tools that demonstrate acquisition of experience and of confidence. © 2013 Springer-Verlag Berlin Heidelberg

CAPTURING TEACHER BASIC NEEDS SATISFACTION: VALIDATION EVIDENCE FOR THE GREEK SCALE MEASURING PE TEACHERS’ BNS

According to self-determination theory, teachers’ basic needs satisfaction is essential for the quality of their motivation, teaching, and work behavior. Considering the lack of valid and reliable instruments measuring teachers’ basic needs satisfaction (for autonomy, competence and relatedness) within the Greek context, we evaluated the factorial validity and internal consistency for the Greek version of the Basic Needs Satisfaction Scale for Teachers (BNSST; Longo et al., 2016). Standard back-translation procedures were followed. Focusing on Physical Education (PE) teachers, the validity of the measure was evaluated via two cross-sectional studies with samples of pre-service (n=109; study 1) and in-service (n=91; study 2) teachers. The psychometric properties of the instrument were established through exploratory and confirmatory factor analysis, Cronbach’s alphas, and latent variables’ associations with external criteria. In both studies, factor analyses results supported the construct validity of the 9-item, 3-correlated factors model, producing satisfactory goodness of fit indices, suggesting that the three needs are positively related with each other. Internal consistency analysis produced acceptable values for all the scales of the study. In line with theoretical assumptions and past research evidence, latent variables correlations with external criteria showed that basic needs satisfaction connects positively with their beneficence, cooperation willingness, intrinsic motivation and identified regulation. Furthermore, structural equation modeling revealed a positive connection between teachers’ general basic needs satisfaction and their autonomous motivation, work engagement, and work satisfaction, suggesting that the fulfillment of teacher basic needs can positively predict their well-being at work. The present findings suggest that the BNSST-GR has good psychometric properties and provide initial support for the instruments’ validity and reliability. Such measurements may prove useful in examining Greek teachers’ basic needs satisfaction in a variety of work-related contexts (e.g., teacher professional development).  Article visualizations

Failure Processes in Embedded Monolayer Graphene under Axial Compression

Exfoliated monolayer graphene flakes were embedded in a polymer matrix and loaded under axial compression. By monitoring the shifts of the 2D Raman phonons of rectangular flakes of various sizes under load, the critical strain to failure was determined. Prior to loading care was taken for the examined area of the flake to be free of residual stresses. The critical strain values for first failure were found to be independent of flake size at a mean value of -0.60 % corresponding to a yield stress of -6 GPa. By combining Euler mechanics with a Winkler approach, we show that unlike buckling in air, the presence of the polymer constraint results in graphene buckling at a fixed value of strain with an estimated wrinkle wavelength of the order of 1-2 nm. These results were compared with DFT computations performed on analogue coronene/ PMMA oligomers and a reasonable agreement was obtained.Comment: 28 pages. Manuscript 20 pages, 8 figures. Supporting information 10 pages, 6 figure