3,336 research outputs found
Why Knowledge Matters
An explanation is given of why it is in the nature of inquiry into whether or not p that its aim is fully achieved only if one comes to know that p or to know that not-p and, further, comes to know how one knows, either way. In the absence of the latter one is in no position to take the inquiry to be successfully completed or to vouch for the truth of the matter in hand. An upshot is that although knowledge matters because truth matters this should not be understood to mean that knowledge matters because true belief matters
Data management of nanometre scale CMOS device simulations
In this paper we discuss the problems arising in managing and curating the data generated by simulations of nanometre scale CMOS (Complementary Metal–Oxide Semiconductor) transistors, circuits and systems and describe the software and operational techniques we have adopted to address them. Such simulations pose a number of challenges including, inter alia, multiTByte data volumes, complex datasets with complex inter-relations between datasets, multi-institutional collaborations including multiple specialisms and a mixture of academic and industrial partners, and demanding security requirements driven by commercial imperatives. This work was undertaken as part of the NanoCMOS project. However, the problems, solutions and experience seem likely to be of wider relevance, both within the CMOS design community and more generally in other disciplines
Secure, performance-oriented data management for nanoCMOS electronics
The EPSRC pilot project Meeting the Design Challenges of nanoCMOS Electronics (nanoCMOS) is focused upon delivering a production level e-Infrastructure to meet the challenges facing the semiconductor industry in dealing with the next generation of ‘atomic-scale’ transistor devices. This scale means that previous assumptions on the uniformity of transistor devices in electronics circuit and systems design are no longer valid, and the industry as a whole must deal with variability throughout the design process. Infrastructures to tackle this problem must provide seamless access to very large HPC resources for computationally expensive simulation of statistic ensembles of microscopically varying physical devices, and manage the many hundreds of thousands of files and meta-data associated with these simulations. A key challenge in undertaking this is in protecting the intellectual property associated with the data, simulations and design process as a whole. In this paper we present the nanoCMOS infrastructure and outline an evaluation undertaken on the Storage Resource Broker (SRB) and the Andrew File System (AFS) considering in particular the extent that they meet the performance and security requirements of the nanoCMOS domain. We also describe how metadata management is supported and linked to simulations and results in a scalable and secure manner
VLTI/MIDI observations of 7 classical Be stars
We measured the mid-infrared extension of the gaseous disk surrounding seven
Be stars in order to constrain the geometry of their circumstellar environments
and to try to infer physical parameters characterizing these disks. We used the
VLTI/MIDI instrument with baselines up to 130 m to obtain an angular resolution
of about 15 mas in the N band and compared our results with previous K band
measurements obtained with the VLTI/AMBER instrument and/or the CHARA
interferometer. We obtained one calibrated visibility measurement for each of
the four stars, p Car, zeta Tau, kappa CMa, and alpha Col, two for delta Cen
and beta CMi, and three for alpha Ara. Almost all targets remain unresolved
even with the largest VLTI baseline of 130m, evidence that their circumstellar
disk extension is less than 10 mas. The only exception is alpha Ara, which is
clearly resolved and well-fitted by an elliptical envelope with a major axis
a=5.8+-0.8mas and an axis ratio a/b=2.4+-1 at 8 microns. This extension is
similar to the size and flattening measured with the VLTI/AMBER instrument in
the K band at 2 microns. The size of the circumstellar envelopes for these
classical Be stars does not seem to vary strongly on the observed wavelength
between 8 and 12microns. Moreover, the size and shape of Alpha Ara's disk is
almost identical at 2, 8, and 12microns
Integrating security solutions to support nanoCMOS electronics research
The UK Engineering and Physical Sciences Research Council (EPSRC) funded Meeting the Design Challenges of nanoCMOS Electronics (nanoCMOS) is developing a research infrastructure for collaborative electronics research across multiple institutions in the UK with especially strong industrial and commercial involvement. Unlike other domains, the electronics industry is driven by the necessity of protecting the intellectual property of the data, designs and software associated with next generation electronics devices and therefore requires fine-grained security. Similarly, the project also demands seamless access to large scale high performance compute resources for atomic scale device simulations and the capability to manage the hundreds of thousands of files and the metadata associated with these simulations. Within this context, the project has explored a wide range of authentication and authorization infrastructures facilitating compute resource access and providing fine-grained security over numerous distributed file stores and files. We conclude that no single security solution meets the needs of the project. This paper describes the experiences of applying X.509-based certificates and public key infrastructures, VOMS, PERMIS, Kerberos and the Internet2 Shibboleth technologies for nanoCMOS security. We outline how we are integrating these solutions to provide a complete end-end security framework meeting the demands of the nanoCMOS electronics domain
OPENMINDS: CREATING A MENTAL HEALTH WORKSHOP FOR TEENAGERS TO TACKLE STIGMA AND RAISE AWARENESS
As a group of four clinical medical students from Cambridge University, we undertook a Student Selected Module (SSC-
"OpenMinds") whereby we designed and delivered a workshop about mental health to year 9 pupils.
The aim of our SSC was to produce an interactive, informative lesson which addressed the complex issues of stigma and
discrimination against those suffering from a mental illness as well as teaching the pupils how to recognise mental health problems
and provide them with guidance on how to seek help. We split a fifty minute session into the following sections: tackling stigma; how
common mental illness is; celebrity examples; real life examples; role play; and small group work. To engage the pupils we used a
combination of teaching modalities targeting all learning. We delivered the workshop to four separate classes and received feedback
from the pupils after each. We used this feedback to adapt and improve our presentation and assess the efficacy. Feedback was
overwhelmingly positive with the striking results of 101/109 pupils saying that they would recommend the workshop to a friend and
68/109 pupils saying they enjoyed all aspects.
Our SSC built upon work by a contingent of trainee Psychiatrists who undertook a similar project of mental health education for
teenagers, called "Heads above the rest", in Northern Ireland with great success. By continuing their work we were able to
demonstrate that medical students can successfully complete the same project under the guidance of a Psychiatrist, thus increasing
the sustainability of the project by reducing the time burden on the Psychiatrists. Participating in the project was also valuable to
our own personal development of teaching skills
M-Band Spectra of Dust Embedded Sources at the Galactic Center
The goal of the present paper is to investigate the circumstellar material
around the brightest dust-enshrouded sources in the central stellar cluster of
the Milky Way. Observations have been carried out at the European Southern
Observatory's Very Large Telescope on Paranal, Chile. We have used the long
wavelength (LWS3) low resolution (LR) spectroscopic mode of the ISAAC camera at
the VLT in the spectral range of the M filter from 4.4micron to 5.1micron. The
use of a slit width of 0.6" implied a spectral resolution of R=l/Dl=800 (Dv=375
km/s). These observations resulted in M-band spectra of 15 bright sources in
the central stellar cluster of the Milky Way. In addition to gaseous 12^CO
(4.666 micron) and 13^CO (4.77 micron) vibration-rotational absorptions, we
detect a strong absorption due to a mixture of polar and apolar CO ice
(centered at 4.675 micron). In the shorter wavelength absorption wing there is
an absorption feature due to XCN at 4.62 micron. The XCN absorption is
strongest toward the M2 supergiant IRS7. We find that the extinctions due to
material traced by the CO ice and the CO gas absorptions may be of comparable
importance. Using the spectra of IRS2L and IRS16C we perform a first order
correction of the line of sight absorption due to CO-ice and 13^CO gas. In
combination with published hydrogen number density estimates from sub-mm
CO(7-6) and FIR [OI] line data we obtain gas masses of the circumstellar shells
of the order of 10^-3 and 10^-2 solar masses. This implies that in future
spectra taken at high spectral and angular resolution the bright and dust
embedded Galactic Center sources should show a substantial line absorption due
to source intrinsic absorption.Comment: 23 pages, 9 figures, Accepted for publication in Ap
Macro Micro Studio:A Prototype Energy Autonomous Laboratory
In 2011, the Departments of Architecture, Physics and Engineering began the development of a small Passivhaus standard, renewable energy self-sufficient studio at the University Botanical Gardens in Dundee. The prototype was conceived as an experimental, integrated technical platform to monitor the performance of an ultra-low-energy consumption, energy positive building in the Scottish climate, and understand user behaviour in relation to managing energy in-use and reducing occupant’s energy consumption. The building fabric has been constructed using regional sustainable materials, including a low-thermal bridging timber kit relying on Scottish small cross-section timber and a novel foam concrete (air entrained) slab foundation. While further work is required to complete the installation of the renewable energy system, predictive modelling indicates that energy autonomy can be largely achieved. With the recent introduction of the new Passivhaus 2009 criteria in October 2015, this project provides an insight into the practical application of an autarkic energy system in a northern European climate. The following paper describes the research rationale, the processes and decision making in the development of the formal and technical design of the building and discusses our current thinking in the design and quantification of the energy system
End-to-End Learning of Geometrical Shaping Maximizing Generalized Mutual Information
GMI-based end-to-end learning is shown to be highly nonconvex. We apply
gradient descent initialized with Gray-labeled APSK constellations directly to
the constellation coordinates. State-of-the-art constellations in 2D and 4D are
found providing reach increases up to 26\% w.r.t. to QAM
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