1,297 research outputs found
Global Entrepreneurship Monitor United Kingdom: 2007 Executive Report
This monitoring report compares Global Entrepreneurship Monitor (GEM) measures of entrepreneurial activity in the UK with participating G7 countries and the large industrialised or industrialising countries of Brazil, Russia, India and China ("BRIC"). It also summarises entrepreneurial activity within Government Office Regions of the UK
The string tension in the maximally Abelian gauge after smoothing
We apply smoothing to SU(2) lattice field configurations in 3+1 dimensions
before fixing to the maximally Abelian gauge. The Abelian projected string
tension is shown to be stable under this, whilst the monopole string tension
declines by O(30%). Blocking of the SU(2) fields reduces this effect, but the
use of extended monopole definitions does not. We discuss these results in the
context of additional confining excitations in the U(1) vacuum.Comment: LATTICE98(confine
Lunch Keynote Speaker — Challenges of Increasing Automation
The theory of automation is that it can eliminate human error by eliminating the human from the loop. Experience has demonstrated, however, that although automation can significantly increase productivity, efficiency, reliability, throughput, and safety, there is a downside. Moreover, the downside can occur not only if the automation does not work as intended, but even if it does work as intended. This presentation will discuss the upsides and downsides of increasing automation
Challenges of Increasing Automation
The theory of automation is that it can eliminate human error by eliminating the human from the loop. Experience has demonstrated, however, that although automation can significantly increase productivity, efficiency, reliability, throughput, and safety, there is a downside. Moreover, the downside can occur not only if the automation does not work as intended, but even if it does work as intended. This presentation will discuss the upsides and downsides of increasing automation
Monopole clusters, Z(2) vortices and confinement in SU(2)
We extend our previous study of magnetic monopole currents in the maximally
Abelian gauge [hep-lat/9712003] to larger lattices at small lattice spacings
(20^4 at beta = 2.5 and 32^4 at beta = 2.5115). We confirm that at these weak
couplings there continues to be one monopole cluster that is very much longer
than the rest and that the string tension, K, is entirely due to it. The
remaining clusters are compact objects whose population as a function of radius
follows a power law that deviates from the scale invariant form, but much too
weakly to suggest a link with the analytically calculable size distribution of
small instantons. We also search for traces of Z(2) vortices in the Abelian
projected fields; either as closed loops of `magnetic' flux or through
appropriate correlations amongst the monopoles. We find, by direct calculation,
that there is no confining condensate of such flux loops. We also find, through
the calculation of doubly charged Wilson loops within the monopole fields, that
there is no suppression of the q=2 effective string tension out to at distances
of at least r ~ 1.6/sqrt{K}, suggesting that if there are any vortices they are
not encoded in the monopole fields.Comment: 26 pages of LaTeX and PostScript figure
On the Phase Diagram of the SU(2) Adjoint Higgs Model in 2+1 Dimensions
The phase diagram is investigated for SU(2) lattice gauge theory in d=3,
coupled to adjoint scalars. For small values of the quartic scalar coupling,
lambda, the transition separating Higgs and confinement phases is found to be
first-order, in agreement with earlier work by Nadkarni. The surface of
second-order transitions conjectured by Nadkarni, however, is shown instead to
correspond to crossover behaviour. This conclusion is based on a finite size
analysis of the scalar mass and susceptibility. The nature of the phase
transition at the termination of first-order behaviour is investigated and we
find evidence for a critical point at which the scalar mass vanishes. The
photon mass and confining string tension are measured and are found to be
negligibly small in the Higgs phase. This is correlated with the very small
density of magnetic monopoles in the Higgs phase. The string tension and photon
mass rise rapidly as the crossover is traversed towards the symmetric phase.Comment: LaTeX. Replaced with version to be published in Physics Letters B.
Minor changes onl
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Principles and objectives of containment verification and performance monitoring and technology selection
While a number of technologies or methods of subsurface imaging and monitoring exist, most require some adaptation to meet the site-specific objectives of a particular in-situ waste containment/stabilization verification and monitoring program. The selection of methods and their site-specific adaptation must be based on sound, scientific principles. Given this, specific information about the site and the objectives of the containment or remediation are required to design and implement an appropriate and effective verification and monitoring program. Site and technology information that must be considered and how it affects the selection and adaptation of monitoring technologies is presented. In general, this information includes the objectives of the containment or remediation, the verification and monitoring systems, and the physical properties of the site and the waste containment/stabilization system. The objectives of the containment or remediation and the verification and monitoring system must be defined to provide a goal for the technology developer`s design. The physical properties of the site and the waste containment/stabilization system are required to ensure the proper technology is selected. A conceptual framework and examples are given to demonstrate the impacts of these aspects on technology selection
Examining coastal dynamics and recreational water quality by quantifying multiple sewage specific markers in a North Carolina estuary
Fecal contamination is observed downstream of municipal separate storm sewer systems in coastal North Carolina. While it is well accepted that wet weather contributes to this phenomenon, less is understood about the contribution of the complex hydrology in this low-lying coastal plain. A quantitative microbial assessment was conducted in Beaufort, North Carolina to identify trends and potential sources of fecal contamination in stormwater receiving waters. Fecal indicator concentrations were significantly higher in receiving water downstream of a tidally submerged outfall compared to an outfall that was permanently submerged (p < 0.001), though tidal height was not predictive of human-specific microbial source tracking (MST) marker concentrations at the tidally submerged site. Short-term rainfall (i.e. <12 h) was predictive of E. coli, Enterococcus spp., and human-specific MST marker concentrations (Fecal Bacteroides, BacHum, and HF183) in receiving waters. The strong correlation between 12-hr antecedent rainfall and Enterococcus spp. (r = 0.57, p < 0.001, n = 92) suggests a predictive model could be developed based on rainfall to communicate risk for bathers. Additional molecular marker data indicates that the delivery of fecal sources is complex and highly variable, likely due to the influence of tidal influx (saltwater intrusion from the estuary) into the low-lying stormwater pipes. In particular, elevated MST marker concentrations (up to 2.56 × 104 gene copies HF183/mL) were observed in standing water near surcharging street storm drain. These data are being used to establish a baseline for stormwater dynamics prior to dramatic rainfall in 2018 and to characterize the interaction between complex stormwater dynamics and water quality impairment in coastal NC
Photoionization of H<sub>2</sub> using the molecular R-matrix with time approach
We present results of the first calculations using the variational ab initio molecular R-matrix with time approach. We have calculated two and four-photon ionization cross sections for H2 and studied the effects of electron correlation and choice of the Gaussian atomic basis sets. Our results are compared with earlier calculations
Bioinspired total synthesis of erectones A and B, and the revised structure of hyperelodione D
Version of record online: March 14, 2022The field of biomimetic synthesis seeks to apply biosynthetic hypotheses to the efficient construction of complex natural products. This approach can also guide the revision of incorrectly assigned structures. Herein, we describe the evolution of a concise total synthesis and structural reassignment of hyperelodione D, a tetracyclic meroterpenoid derived from a Hypericum plant, alongside some biogenetically related natural products, erectones A and B. The key step in the synthesis of hyperelodione D forms six stereocentres and three rings in a bioinspired cascade reaction that features an intermolecular Diels-Alder reaction, an intramolecular Prins reaction and a terminating cycloetherification.Liam J. Franov, Jacob D. Hart, Glenn A. Pullella, Christopher J. Sumby, and Jonathan H. Georg
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