516 research outputs found
York City Environmental Observatory : WP4 model integration
This work is produced as part of the York Urban Living Pilot (ULP) project an RCUK funded project to develop the York City Environmental Observatory (YCEO). The project is led by York University with York City Council as lead partners and other organisations including BGS. Split into a number of Work Packages (WPs), WP4 aims to set out the design for the implementation phase of the YCEO. This report forms part of the deliverables of WP4 and is concerned with model integration and aims to determine which models are available for the York area and how they could be integrated into the YCEO.
The information was obtained by internet searches, literature review, and investigating known projects to determine: a) what models are out there and b) how model integration could be undertaken
Evidence showed limited metadata for models of the York area, even though there is knowledge of models available. There is also limited examples of model integration platforms in the âsmart cityâ context or even urban environments. However, exemplars exist including predictive analytics built on open data platforms and workflow approaches such as the Innovate UK funded Tombolo project. Application programming Interfaces (APIs) also offer possibilities in the UK with the Met Office and the Environment Agency making both observed data and model forecasts available via this method. A simple example is presented using APIs to determine when it is safe to row ont eh River Ouse, York.
Model integration is problematic, but it can take many forms and Tombolo offers the opportunity to enable pre-formed solutions to be made available. The YCEO model platform should be based on pre-formed solutions using the Tombolo approach with semantic reasoning at its basis
Effect of process parameters and optimization of CO2 laser cutting of ultra high performance polyethylene
The aim of this work is to relate the cutting edge quality parameters (responses) namely: upper kerf, lower kerf, ratio of the upper kerf to lower kerf and cut edge roughness to the process parameters considered in this research and to find out the optimal cutting conditions. The process factors implemented in this research are: laser power, cutting speed and focal point position. Design of experiment (DoE) was used by implementing Box-Behnken design to achieve better cut qualities within existing resources. Mathematical models were developed to establish the relationship between the process parameters and the edge quality parameters. Also, the effects of process parameters on each response were determine. Then, a numerical optimization was performed to find out the optimal process setting at which the quality features are at their desired values. The effect of each factor on the responses was established and the optimal cutting conditions were found
Investigating the CO2 laser cutting parameters of MDF wood composite material
Laser cutting of medium density fibreboard (MDF) is a complicated process and the selection of the process parameters combinations is essential to get the highest quality of the cut section. This paper presents laser cutting of MDF based on design of experiments (DOE). CO2 laser was used to cut three thicknesses 4, 6 and 9 mm of MDF panels. The process factors investigated are: laser power, cutting speed, air pressure and focal point position. In this work, cutting quality was evaluated by measuring, upper kerf width, lower kerf width, ratio between the upper kerf width to the lower kerf width, cut section roughness and the operating cost. The effect of each factor on the quality measures was determined and special graphs were drawn for this purpose. The optimal cutting combinations were presented in favours of high quality process output and in favours of low cutting cost
Effect of CO2 laser cutting process parameters on edge quality and operating cost of AISI316L
Laser cutting is a popular manufacturing process utilized to cut various types of materials economically. The width of laser cut or kerf, quality of the cut edges and the operating cost are affected by laser power, cutting speed, assist gas pressure, nozzle diameter and focus point position as well as the work-piece material. In this paper CO2 laser cutting of stainless steel of medical grade AISI316L has been investigated. Design of experiment (DOE) was implemented by applying Box-Behnken design to develop the experiment lay-out. The aim of this work is to relate the cutting edge quality parameters namely: upper kerf, lower kerf, the ratio between them, cut section roughness and operating cost to the process parameters mentioned above. Then, an overall optimization routine was applied to find out the optimal cutting setting that would enhance the quality or minimize the operating cost. Mathematical models were developed to determine the relationship between the process parameters and the edge quality features. Also, process parameters effects on the quality features have been defined. Finally, the optimal laser cutting conditions have been found at which the highest quality or minimum cost can be achieved
Evalaution and optimization of laser cutting parameters for plywood materials
Laser process parameters influence greatly the width of kerfs and quality of the cut edges. This article reports experiments on the laser plywood-cutting performance of a CW 1.5 kW CO2ÂŹ Rofin laser, based on design of experiments (DOE). The laser was used to cut three thicknesses 3, 6 and 9 mm of plywood panels. The process factors investigated are: laser power, cutting speed, air pressure and focal point position. The aim of this work is to relate the cutting edge quality parameters namely: upper kerf (UK), lower kerf (LK), the ratio between upper to lower kerfs and the operating cost to the process parameters mentioned above. Mathematical models were developed to establish the relationship between the process parameters and the edge quality parameters, and special graphs were drawn for this purpose. Finally, a numerical optimization was performed to find out the optimal process setting at which both kerfs would lead to a ratio of about 1, and at which low cutting cost take place
Probing the primordial power spectra with inflationary priors
We investigate constraints on power spectra of the primordial curvature and
tensor perturbations with priors based on single-field slow-roll inflation
models. We stochastically draw the Hubble slow-roll parameters and generate the
primordial power spectra using the inflationary flow equations. Using data from
recent observations of CMB and several measurements of geometrical distances in
the late Universe, Bayesian parameter estimation and model selection are
performed for models that have separate priors on the slow-roll parameters. The
same analysis is also performed adopting the standard parameterization of the
primordial power spectra. We confirmed that the scale-invariant
Harrison-Zel'dovich spectrum is disfavored with increased significance from
previous studies. While current observations appear to be optimally modeled
with some simple models of single-field slow-roll inflation, data is not enough
constraining to distinguish these models.Comment: 23 pages, 3 figures, 7 tables, accepted for publication in JCA
Single-field inflation constraints from CMB and SDSS data
We present constraints on canonical single-field inflation derived from WMAP
five year, ACBAR, QUAD, BICEP data combined with the halo power spectrum from
SDSS LRG7. Models with a non-scale-invariant spectrum and a red tilt n_s < 1
are now preferred over the Harrison-Zel'dovich model (n_s = 1, tensor-to-scalar
ratio r = 0) at high significance. Assuming no running of the spectral indices,
we derive constraints on the parameters (n_s, r) and compare our results with
the predictions of simple inflationary models. The marginalised credible
intervals read n_s = 0.962^{+0.028}_{-0.026} and r < 0.17 (at 95% confidence
level). Interestingly, the 68% c.l. contours favour mainly models with a convex
potential in the observable region, but the quadratic potential model remains
inside the 95% c.l. contours. We demonstrate that these results are robust to
changes in the datasets considered and in the theoretical assumptions made. We
then consider a non-vanishing running of the spectral indices by employing
different methods, non-parametric but approximate, or parametric but exact.
With our combination of CMB and LSS data, running models are preferred over
power-law models only by a Delta chi^2 ~ 5.8, allowing inflationary stages
producing a sizable negative running -0.063^{+0.061}_{-0.049} and larger
tensor-scalar ratio r < 0.33 at the 95% c.l. This requires large values of the
third derivative of the inflaton potential within the observable range. We
derive bounds on this derivative under the assumption that the inflaton
potential can be approximated as a third order polynomial within the observable
range.Comment: 32 pages, 7 figures. v2: additional references, some typos corrected,
passed to JCAP style. v3: minor changes, matches published versio
BCS and BEC p-wave pairing in Bose-Fermi gases
The pairing of fermionic atoms in a mixture of atomic fermion and boson gases
at zero temperature is investigated. The attractive interaction between
fermions, that can be induced by density fluctuations of the bosonic
background, can give rise to a superfluid phase in the Fermi component of the
mixture. The atoms of both species are assumed to be in only one internal
state, so that the pairing of fermions is effective only in odd-l channels. No
assumption about the value of the ratio between the Fermi velocity and the
sound velocity in the Bose gas is made in the derivation of the energy gap
equation. The gap equation is solved without any particular "ansatz" for the
pairing field or the effective interaction. The p-wave superfluidity is studied
in detail. By increasing the strength and/or decreasing the range of the
effective interaction a transition of the fermion pairing regime, from the
Bardeen-Cooper-Schrieffer state to a system of tightly bound couples can be
realized. These composite bosons behave as a weakly-interacting Bose-Einstein
condensate.Comment: 14 pages, 6 eps-figures. To be published in European Physical Journal
Charged-Particle Multiplicities in Charged-Current Neutrino-- and Anti-Neutrino--Nucleus Interactions
The CHORUS experiment, designed to search for
oscillations, consists of a nuclear emulsion target and electronic detectors.
In this paper, results on the production of charged particles in a small sample
of charged-current neutrino-- and anti-neutrino--nucleus interactions at high
energy are presented. For each event, the emission angle and the ionization
features of the charged particles produced in the interaction are recorded,
while the standard kinematic variables are reconstructed using the electronic
detectors. The average multiplicities for charged tracks, the pseudo-rapidity
distributions, the dispersion in the multiplicity of charged particles and the
KNO scaling are studied in different kinematical regions. A study of
quasi-elastic topologies performed for the first time in nuclear emulsions is
also reported. The results are presented in a form suitable for use in the
validation of Monte Carlo generators of neutrino--nucleus interactions.Comment: 17 pages, 5 figure
Gene transcripts associated with muscle strength: a CHARGE meta-analysis of 7,781 persons
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Background: Lower muscle strength in midlife predicts disability and mortality in later life. Bloodborne factors, including growth differentiation factor 11 (GDF11), have been linked to muscle regeneration in animal models. We aimed to identify gene transcripts associated with muscle strength in adults. Methods: Meta-analysis of whole blood gene expression (overall 17,534 unique genes measured by microarray) and hand-grip strength in four independent cohorts (n=7,781, ages: 20-104 years, weighted mean=56), adjusted for age, sex, height, weight, and leukocyte subtypes. Separate analyses were performed in subsets (older/younger than 60, male/female). Results: Expression levels of 221 genes were associated with strength after adjustment for cofactors and for multiple statistical testing, including ALAS2 (rate limiting enzyme in heme synthesis), PRF1 (perforin, a cytotoxic protein associated with inflammation), IGF1R and IGF2BP2 (both insulin like growth factor related). We identified statistical enrichment for hemoglobin biosynthesis, innate immune activation and the stress response. Ten genes were only associated in younger individuals, four in males only and one in females only. For example PIK3R2 (a negative regulator of PI3K/AKT growth pathway) was negatively associated with muscle strength in younger (=60 years). We also show that 115 genes (52%) have not previously been linked to muscle in NCBI PubMed abstracts Conclusions: This first large-scale transcriptome study of muscle strength in human adults confirmed associations with known pathways and provides new evidence for over half of the genes identified. There may be age and sex specific gene expression signatures in blood for muscle strength.Wellcome TrustFHS gene expression profiling was funded through the Division of Intramural Research
(Principal Investigator, Daniel Levy), National Heart, Lung, and Blood Institute, National
Institutes of Health, Bethesda, MD. Dr. Murabito is supported by NIH grant R01AG029451.
Dr. Kiel is supported by NIH R01 AR41398. The Framingham Heart Study is supported by
National Heart, Lung, and Blood Institute contract N01-HC-25195.The InCHIANTI study was supported in part by the Intramural Research Program, National
Institute on Aging, NIH, Baltimore MD USA. D.M. and L.W.H. were generously supported by
a Wellcome Trust Institutional Strategic Support Award (WT097835MF). W.E.H. was funded
by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied
Health Research and Care (CLAHRC) for the South West Peninsula. The views expressed in
this publication are those of the authors and not necessarily those of the NHS, the NIHR or
the Department of Health in EnglandThe infrastructure for the NESDA study (www.nesda.nl) is funded through the Geestkracht
program of the Netherlands Organisation for Health Research and Development (Zon-Mw,
grant number 10-000-1002) and is supported by participating universities and mental health
care organizations (VU University Medical Center, GGZ inGeest, Arkin, Leiden University
Medical Center, GGZ Rivierduinen, University Medical Center Groningen, Lentis, GGZ
Friesland, GGZ Drenthe, Scientific Institute for Quality of Healthcare (IQ healthcare),
Netherlands Institute for Health Services Research (NIVEL) and Netherlands Institute of
Mental Health and Addiction (Trimbos Institute).The Rotterdam Study is funded by Erasmus Medical Center and Erasmus University,
Rotterdam, Netherlands Organization for the Health Research and Development (ZonMw),
the Netherlands Organisation of Scientific Research NWO Investments (nr.
175.010.2005.011, 911-03-012), the Research Institute for Diseases in the Elderly (014-93-
28
015; RIDE2), the Ministry of Education, Culture and Science, the Ministry for Health, Welfare
and Sports, the European Commission (DG XII), and the Municipality of Rotterdam. The
authors are grateful to the study participants, the staff from the Rotterdam Study and the
participating general practitioners and pharmacists. The generation and management of
RNA-expression array data for the Rotterdam Study was executed and funded by the Human
Genotyping Facility of the Genetic Laboratory of the Department of Internal Medicine,
Erasmus MC, the Netherlands. We thank Marjolein Peters, MSc, Ms. Mila Jhamai, Ms.
Jeannette M. Vergeer-Drop, Ms. Bernadette van Ast-Copier, Mr. Marijn Verkerk and Jeroen
van Rooij, BSc for their help in creating the RNA array expression databaseSHIP is part of the Community Medicine Research net of the University of Greifswald,
Germany, which is funded by the Federal Ministry of Education and Research (grants no.
01ZZ9603, 01ZZ0103, and 01ZZ0403), the Ministry of Cultural Affairs as well as the Social
Ministry of the Federal State of Mecklenburg-West Pomerania, and the network âGreifswald
Approach to Individualized Medicine (GANI_MED)â funded by the Federal Ministry of
Education and Research (grant 03IS2061A). The University of Greifswald is a member of the
'Center of Knowledge Interchange' program of the Siemens AG and the Caché Campus
program of the InterSystems GmbH
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