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Reduction of Machine Tool Times Through a Software/Hardware Integrated Solution
Toolmaking is an industry that creates metal moulds, generally of durable tool steels, for
producing vacuum-formed and injection moulded plastic parts, which are used in thousands
of everyday items such as mobile phones. At present toolmaking is labour intensive with each
machining operation requiring manual supervision. The FASTOOL project was a European
Union funded collaboration that was aimed at reducing the manpower content of mould
toolmaking, and extending the working day. This paper focuses on one element which utilised
specially created scheduling and control software that operated an automated overhead gantry
system and could remotely start the workshop machines. The software was completely object
oriented which allows future proofing by creating new objects for new machines. The results
demonstrate that this manufacturing process can be automated, leading to better working
conditions for employees and an increase in efficiency and profitability.Mechanical Engineerin
Symmetry violations at BABAR
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd.2014 J. Phys.: Conf. Ser. 556 012042
(http://iopscience.iop.org/1742-6596/556/1/012042
Digital Doppler extraction demonstration with the advanced receiver
A digital Doppler extraction demonstration with the Advanced Receiver 2 (ARX 2) tracking Pioneer 10 and Voyager 2 is described. The measured results are compared with those of the Block 4 receiver that was operating in parallel with the ARX 2. It is shown that the ARX 2 outperforms the Block 4 receiver in terms of Allan variance of the Doppler residuals, the amount of which depends on the scenario of interest
Asymptotic motion of a single vortex in a rotating cylinder
We study numerically the behavior of a single quantized vortex in a rotating
cylinder. We study in particular the spiraling motion of a vortex in a cylinder
that is parallel to the rotation axis. We determine the asymptotic form of the
vortex and its axial and azimuthal propagation velocities under a wide range of
parameters. We also study the stability of the vortex line and the effect of
tilting the cylinder from the rotation axis.Comment: 9 pages, 10 figures. Considerable changes, now close to the published
versio
A decade of ejecta dust formation in the Type IIn SN 2005ip
In order to understand the contribution of core-collapse supernovae to the
dust budget of the early universe, it is important to understand not only the
mass of dust that can form in core-collapse supernovae but also the location
and rate of dust formation. SN 2005ip is of particular interest since dust has
been inferred to have formed in both the ejecta and the post-shock region
behind the radiative reverse shock. We have collated eight optical archival
spectra that span the lifetime of SN 2005ip and we additionally present a new
X-shooter optical-near-IR spectrum of SN 2005ip at 4075d post-discovery. Using
the Monte Carlo line transfer code DAMOCLES, we have modelled the blueshifted
broad and intermediate width H, H and He I lines from 48d to
4075d post-discovery using an ejecta dust model. We find that dust in the
ejecta can account for the asymmetries observed in the broad and intermediate
width H, H and He I line profiles at all epochs and that it is
not necessary to invoke post-shock dust formation to explain the blueshifting
observed in the intermediate width post-shock lines. Using a Bayesian approach,
we have determined the evolution of the ejecta dust mass in SN 2005ip over 10
years presuming an ejecta dust model, with an increasing dust mass from
~10 M at 48d to a current dust mass of 0.1 M.Comment: Accepted by MNRAS, 17 pages, 11 figures. Author accepted manuscript.
Accepted on 04/03/19. Deposited on 07/03/1
Interactions In Space For Archaeological Models
In this article we examine a variety of quantitative models for describing
archaeological networks, with particular emphasis on the maritime networks of
the Aegean Middle Bronze Age. In particular, we discriminate between those
gravitational networks that are most likely (maximum entropy) and most
efficient (best cost/benefit outcomes).Comment: 21 pages, 6 figures, 2 tables. Contribution to special issue of
Advances in Complex Systems from the conference `Cultural Evolution in
Spatially Structured Populations', UCL, London, September 2010. To appear in
Advances in Complex System
Extended Huckel theory for bandstructure, chemistry, and transport. II. Silicon
In this second paper, we develop transferable semi-empirical parameters for
the technologically important material, silicon, using Extended Huckel Theory
(EHT) to calculate its electronic structure. The EHT-parameters areoptimized to
experimental target values of the band dispersion of bulk-silicon. We obtain a
very good quantitative match to the bandstructure characteristics such as
bandedges and effective masses, which are competitive with the values obtained
within an orthogonal-tight binding model for silicon. The
transferability of the parameters is investigated applying them to different
physical and chemical environments by calculating the bandstructure of two
reconstructed surfaces with different orientations: Si(100) (2x1) and Si(111)
(2x1). The reproduced - and -surface bands agree in part
quantitatively with DFT-GW calculations and PES/IPES experiments demonstrating
their robustness to environmental changes. We further apply the silicon
parameters to describe the 1D band dispersion of a unrelaxed rectangular
silicon nanowire (SiNW) and demonstrate the EHT-approach of surface passivation
using hydrogen. Our EHT-parameters thus provide a quantitative model of
bulk-silicon and silicon-based materials such as contacts and surfaces, which
are essential ingredients towards a quantitative quantum transport simulation
through silicon-based heterostructures.Comment: 9 pages, 9 figure
Allosteric Conversation in the Androgen Receptor Ligand-Binding Domain Surfaces
Androgen receptor (AR) is a major therapeutic target that plays pivotal roles in prostate cancer (PCa) and androgen insensitivity syndromes. Wepreviously proposed that compounds recruited to ligand-binding domain (LBD) surfaces could regulate AR activity in hormone-refractory PCa and discovered several surface modulators of AR function. Surprisingly, the most effective compounds bound preferentially to a surface of unknown function [binding function 3 (BF-3)] instead of the coactivator-binding site [activation function 2 (AF-2)]. Different BF-3 mutations have been identified in PCa or androgen insensitivity syndrome patients, and they can strongly affect AR activity. Further, comparison of AR x-ray structures with and without bound ligands at BF-3 and AF-2 showed structural coupling between both pockets. Here, we combine experimental evidence and molecular dynamic simulations to investigate whether BF-3 mutations affect AR LBD function and dynamics possibly via allosteric conversation between surface sites. Our data indicate that AF-2 conformation is indeed closely coupled to BF-3 and provide mechanistic proof of their structural interconnection. BF-3 mutations may function as allosteric elicitors, probably shifting the AR LBD conformational ensemble toward conformations that alter AF-2 propensity to reorganize into subpockets that accommodate N-terminal domain and coactivator peptides. The induced conformation may result in either increased or decreased AR activity. Activating BF-3 mutations also favor the formation of another pocket (BF-4) in the vicinity of AF-2 and BF-3, which we also previously identified as a hot spot for a small compound. We discuss the possibility that BF-3 may be a protein-docking site that binds to the N-terminal domain and corepressors. AR surface sites are attractive pharmacological targets to develop allosteric modulators that might be alternative lead compounds for drug design. © 2012 by The Endocrie Society
What drives biodiversity patterns? Using long-term multidisciplinary data to discern centennial-scale change
1. Biodiversity plays an important role in ecosystem functioning, habitat recovery following disturbance and resilience to global environmental change. Long‐term ecological records can be used to explore biodiversity patterns and trends over centennial to multi‐millennial time‐scales across broad regions. Fossil pollen grains preserved in sediment over millennia reflect palynological richness and diversity, which relates to changes in landscape diversity. Other long‐term environmental data, such as fossil insects, palaeoclimate and archaeologically inferred palaeodemographic (population) data, hold potential to address questions about the drivers and consequences of diversity change when combined with fossil pollen records.
2. This study tests a model of Holocene palynological diversity change through a synthesis of pollen and insect records from across the British Isles along with palaeodemographic trends and palaeoclimate records. We demonstrate relationships between human population change, insect faunal group turnover, palynological diversity and climate trends through the Holocene.
3. Notable increases in population at the start of the British Neolithic (~6,000 calendar years before present [bp]) and Bronze Age (~4,200 bp) coincided with the loss of forests, increased agricultural activity and changes in insect faunal groups to species associated with human land use. Pollen diversity and evenness increased, most notably since the Bronze Age, as landscapes became more open and heterogeneous. However, regionally distinctive patterns are also evident within the context of these broad‐scale trends. Palynological diversity is correlated with population while diversity and population are correlated with some climate datasets during certain time periods (e.g. Greenland temperature in the mid‐late Holocene).
4. Synthesis. This study has demonstrated that early human societies contributed to shaping palynological diversity patterns over millennia within the context of broader climatic influences upon vegetation. The connections between population and palynological diversity become increasingly significant in the later Holocene, implying intensifying impacts of human activity, which may override climatic effects. Patterns of palynological diversity trends are regionally variable and do not always follow expected trajectories. To fully understand the long‐term drivers of biodiversity change on regionally relevant ecological and management scales, future research needs to focus on amalgamating diverse data types, along with multi‐community efforts to harmonise data across broad regions
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