11,968 research outputs found
Self-induced structure in the current-voltage characteristics of RSQUIDs
Resistive two-junction SQUIDs (RSQUIDs) made from high-temperature superconductors are being developed as narrow-linewidth tunable oscillators in the GHz frequency range. We present here the results of numerical simulation of RSQUIDs of this type. These studies have identified conditions where sub-harmonic steps and other features are apparent in the current-voltage characteristics, driven by the internally-generated heterodyne frequency. The behavior is sensitive to the frequency (set by the voltage across the resistive element in the RSQUID), the temperature and also the loop inductance. We have studied the effects of thermal noise on these features. We also assess how these effects might be observed, and consider how they might affect practical applications of high frequency heterodyne RSQUID oscillators
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Dismantling the signposts to public health? NHS data under the Health and Social Care Act 2012
The Health and Social Care Act 2012 will replace the administrative structure of the NHS in England, currently based on the resident populations of defined geographical areas, with one that relates instead to the shifting populations of individuals registered with specific general practices at given points in time.1 This will radically change the longstanding basis for collecting data routinely about the health needs of local populations, making it difficult to monitor the effect of new legislation on the health of the population locally or nationally.2 3 We discuss some of the implications of the act for existing routine data systems and the production of routine statistics that underpin essential NHS functions, including monitoring healthcare provision and ensuring equity of access, allocation of resources, and measurement of outcomes
Test, Control and Monitor System (TCMS) operations plan
The purpose is to provide a clear understanding of the Test, Control and Monitor System (TCMS) operating environment and to describe the method of operations for TCMS. TCMS is a complex and sophisticated checkout system focused on support of the Space Station Freedom Program (SSFP) and related activities. An understanding of the TCMS operating environment is provided and operational responsibilities are defined. NASA and the Payload Ground Operations Contractor (PGOC) will use it as a guide to manage the operation of the TCMS computer systems and associated networks and workstations. All TCMS operational functions are examined. Other plans and detailed operating procedures relating to an individual operational function are referenced within this plan. This plan augments existing Technical Support Management Directives (TSMD's), Standard Practices, and other management documentation which will be followed where applicable
Observationally-Motivated Analysis of Simulated Galaxies
The spatial and temporal relationships between stellar age, kinematics, and
chemistry are a fundamental tool for uncovering the physics driving galaxy
formation and evolution. Observationally, these trends are derived using
carefully selected samples isolated via the application of appropriate
magnitude, colour, and gravity selection functions of individual stars;
conversely, the analysis of chemodynamical simulations of galaxies has
traditionally been restricted to the age, metallicity, and kinematics of
`composite' stellar particles comprised of open cluster-mass simple stellar
populations. As we enter the Gaia era, it is crucial that this approach
changes, with simulations confronting data in a manner which better mimics the
methodology employed by observers. Here, we use the \textsc{SynCMD} synthetic
stellar populations tool to analyse the metallicity distribution function of a
Milky Way-like simulated galaxy, employing an apparent magnitude plus gravity
selection function similar to that employed by the RAdial Velocity Experiment
(RAVE); we compare such an observationally-motivated approach with that
traditionally adopted - i.e., spatial cuts alone - in order to illustrate the
point that how one analyses a simulation can be, in some cases, just as
important as the underlying sub-grid physics employed.Comment: Accepted for publication in PoS (Proceedings of Science): Nuclei in
the Cosmos XIII (Debrecen, Jul 2014); 6 pages; 3 figure
Galactic Archaeology and Minimum Spanning Trees
Chemical tagging of stellar debris from disrupted open clusters and
associations underpins the science cases for next-generation multi-object
spectroscopic surveys. As part of the Galactic Archaeology project TraCD
(Tracking Cluster Debris), a preliminary attempt at reconstructing the birth
clouds of now phase-mixed thin disk debris is undertaken using a parametric
minimum spanning tree (MST) approach. Empirically-motivated chemical abundance
pattern uncertainties (for a 10-dimensional chemistry-space) are applied to
NBODY6-realised stellar associations dissolved into a background sea of field
stars, all evolving in a Milky Way potential. We demonstrate that significant
population reconstruction degeneracies appear when the abundance uncertainties
approach 0.1 dex and the parameterised MST approach is employed; more
sophisticated methodologies will be required to ameliorate these degeneracies.Comment: To appear in "Multi-Object Spectroscopy in the Next Decade: Big
Questions, Large Surveys and Wide Fields"; Held: Santa Cruz de La Palma,
Canary Islands, Spain, 2-6 Mar 2015; ed. I Skillen & S. Trager; ASP
Conference Series (Figures now optimised for B&W printing
The effect of an internet option and single-sided printing format to increase the response rate to a population-based study : a randomized controlled trial
Acknowledgements We would like to thank the Institute of Applied Health Sciences (IAHS) at the University of Aberdeen for funding the PhD studentship of EF. Furthermore, we would like to thank everyone who was involved in the study, including Professor Sir Lewis Ritchie (Director of Public Health, NHS Grampian), John Lemon (University of Aberdeen), Dr. Fiona Garton (University of Aberdeen) and the Aberdeen Service User Group. Lastly, we would like to acknowledge all data entry clerks (Maxx Livingstone, Rory Macfarlane, Georgia Mannion-Krase and Hazel Reilly) and participants of the study.Peer reviewedPublisher PD
On characteristic equations, trace identities and Casimir operators of simple Lie algebras
Two approaches are developed to exploit, for simple complex or compact real
Lie algebras g, the information that stems from the characteristic equations of
representation matrices and Casimir operators. These approaches are selected so
as to be viable not only for `small' Lie algebras and suitable for treatment by
computer algebra. A very large body of new results emerges in the forms, a) of
identities of a tensorial nature, involving structure constants etc. of g, b)
of trace identities for powers of matrices of the adjoint and defining
representations of g, c) of expressions of non-primitive Casimir operators of g
in terms of primitive ones. The methods are sufficiently tractable to allow not
only explicit proof by hand of the non-primitive nature of the quartic Casimir
of g2, f4, e6, but also e.g. of that of the tenth order Casimir of f4.Comment: 39 pages, 8 tables, late
Alien Registration- Macfarlane, Edith M. (Houlton, Aroostook County)
https://digitalmaine.com/alien_docs/34729/thumbnail.jp
- …