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Argument maps as policy memories for informed deliberation: A research note
This is an eGISE network paper. A significant area within eGovernment is concerned with systems to
support democratic policy formation and decision making processes. In modern government, both
local and national, consultation with interested parties is an important element in maintaining the
democratic process. To date online consultation tools have has used existing software tools, which are
simple text based tools that were not tailored to the process. This project proposes to develop an
online tool that will visualise the issues and arguments graphically as the consultation process
proceeds. Using Discourse Analysis and Ontological Engineering it will create Argument Maps that
will server not only to inform participants but also the archive record of the consultation â the Policy
Memory. We hypothesise that such a tool would allow citizens to be come more engaged with policy
formation and enhance democratic participation
Local Area Dynamic Routing Protocol: a Position Based Routing Protocol for MANET
A Mobile Ad Hoc Network (MANET) comprises mobile nodes (MNs), equipped with wireless
communications devices; which form a temporary communication network without fixed
network infrastructure or topology.
The characteristics of MANET are: limited bandwidth; limited radio range; high mobility; and
vulnerability to attacks that degrade the signal to noise ratio and bit error rates. These
characteristics create challenges to MANET routing protocols. In addition, the mobility pattern
of the MNs also has major impact on the MANET routing protocols.
The issue of routing and maintaining packets between MNs in the mobile ad hoc networks
(MANETs) has always been a challenge; i.e. encountering broadcast storm under high node
density, geographically constrained broadcasting of a service discovery message and local
minimum problem under low node density. This requires an efficient design and development
of a lightweight routing algorithm which can be handled by those GPS equipped devices.
Most proposed location based routing protocols however, rely on a single route for each data
transmission. They also use a location based system to find the destination address of MNs
which over time, will not be accurate and may result in routing loop or routing failure.
Our proposed lightweight protocol, âLocal Area Network Dynamic Routingâ (LANDY) uses a
localized routing technique which combines a unique locomotion prediction method and
velocity information of MNs to route packets. The protocol is capable of optimising routing
performance in advanced mobility scenarios, by reducing the control overhead and improving
the data packet delivery.
In addition, the approach of using locomotion prediction, has the advantage of fast and accurate
routing over other position based routing algorithms in mobile scenarios. Recovery with
LANDY is faster than other location protocols, which use mainly greedy algorithms, (such as
GPRS), no signalling or configuration of the intermediate nodes is required after a failure.
The key difference is that it allows sharing of locomotion and velocity information among the
nodes through locomotion table. The protocol is designed for applications in which we expect
that nodes will have access to a position service (e.g., future combat system). Simulation results
show that LANDY`s performance improves upon other position based routing protocols
Astrometric Monitoring of the HR 8799 Planets: Orbit Constraints from Self-Consistent Measurements
We present new astrometric measurements from our ongoing monitoring campaign
of the HR 8799 directly imaged planetary system. These new data points were
obtained with NIRC2 on the W.M. Keck II 10 meter telescope between 2009 and
2014. In addition, we present updated astrometry from previously published
observations in 2007 and 2008. All data were reduced using the SOSIE algorithm,
which accounts for systematic biases present in previously published
observations. This allows us to construct a self-consistent data set derived
entirely from NIRC2 data alone. From this dataset, we detect acceleration for
two of the planets (HR 8799b and e) at 3. We also assess possible
orbital parameters for each of the four planets independently. We find no
statistically significant difference in the allowed inclinations of the
planets. Fitting the astrometry while forcing coplanarity also returns
consistent to within 1 of the best fit values, suggesting that if
inclination offsets of 20 are present, they are not detectable
with current data. Our orbital fits also favor low eccentricities, consistent
with predictions from dynamical modeling. We also find period distributions
consistent to within 1 with a 1:2:4:8 resonance between all planets.
This analysis demonstrates the importance of minimizing astrometric systematics
when fitting for solutions to highly undersampled orbits.Comment: 18 pages, 11 figures. Accepted for publication in A
Climate Change and National Laws across Commonwealth Countries
This paper furthers the Commonwealth agenda on climate action by exploring the kinds of âpractical and swift actionâ that might be taken through national legal frameworks to implement the Paris Agreement. The paper reviews national laws of Commonwealth member countries as they currently apply to and intersect with climate change. The paper investigates legal measures that relate directly to implement climate change policy, including climate change legislation and regulatory instruments such as emissions trading schemes and energy efficiency measures. It also considers indirect legal measures that can provide âco-benefitsâ in relation to climate change policy, such as waste legislation and air quality measures. The paper presents examples of these different kinds of climate intersections in different Commonwealth legal systems, highlighting examples of what has worked well and what has not worked well to date, within different legal, economic and political cultures, and in different geographies and climates
High-contrast imaging in the Hyades with snapshot LOCI
To image faint substellar companions obscured by the stellar halo and
speckles, scattered light from the bright primary star must be removed in
hardware or software. We apply the "locally-optimized combination of images"
(LOCI) algorithm to 1-minute Keck Observatory snapshots of GKM dwarfs in the
Hyades using source diversity to determine the most likely PSF. We obtain a
mean contrast of 10^{-2} at 0.01", 10^{-4} at <1", and 10^{-5} at 5". New brown
dwarf and low-mass stellar companions to Hyades primaries are found in a third
of the 84 targeted systems. This campaign shows the efficacy of LOCI on
snapshot imaging as well as on bright wide binaries with off-axis LOCI,
reaching contrasts sufficient for imaging 625-Myr late-L/early-T dwarfs purely
in post-processing.Comment: 12 pages, 12 figures, to appear in SPIE Astronomy 2012, paper
8447-16
Magnon softening in a ferromagnetic monolayer: a first-principles spin dynamics study
We study the Fe/W(110) monolayer system through a combination of first
principles calculations and atomistic spin dynamics simulations. We focus on
the dispersion of the spin waves parallel to the [001] direction. Our results
compare favorably with the experimental data of Prokop et al. [Phys. Rev. Lett.
102, 177206], and correctly capture a drastic softening of the magnon spectrum,
with respect to bulk bcc Fe. The suggested shortcoming of the itinerant
electron model, in particular that given by density functional theory, is
refuted. We also demonstrate that finite temperature effects are significant,
and that atomistic spin dynamics simulations represent a powerful tool with
which to include these.Comment: v1: 11 pages, 3 figures. v2: double column, 5 pages, 3 figures, typos
corrected, references adde
Exoplanet Detection Techniques
We are still in the early days of exoplanet discovery. Astronomers are
beginning to model the atmospheres and interiors of exoplanets and have
developed a deeper understanding of processes of planet formation and
evolution. However, we have yet to map out the full complexity of multi-planet
architectures or to detect Earth analogues around nearby stars. Reaching these
ambitious goals will require further improvements in instrumentation and new
analysis tools. In this chapter, we provide an overview of five observational
techniques that are currently employed in the detection of exoplanets: optical
and IR Doppler measurements, transit photometry, direct imaging, microlensing,
and astrometry. We provide a basic description of how each of these techniques
works and discuss forefront developments that will result in new discoveries.
We also highlight the observational limitations and synergies of each method
and their connections to future space missions.Comment: 24 pages, 19 figures, PPVI proceedings. Appears as 2014, Protostars
and Planets VI, Henrik Beuther, Ralf S. Klessen, Cornelis P. Dullemond, and
Thomas Henning (eds.), University of Arizona Press, Tucson, 914 pp.,
p.715-73
Early Life Conditions and Physiological Stress following the Transition to Farming in Central/Southeast Europe: Skeletal Growth Impairment and 6000 Years of Gradual Recovery.
Early life conditions play an important role in determining adult body size. In particular, childhood malnutrition and disease can elicit growth delays and affect adult body size if severe or prolonged enough. In the earliest stages of farming, skeletal growth impairment and small adult body size are often documented relative to hunter-gatherer groups, though this pattern is regionally variable. In Central/Southeast Europe, it is unclear how early life stress, growth history, and adult body size were impacted by the introduction of agriculture and ensuing long-term demographic, social, and behavioral change. The current study assesses this impact through the reconstruction and analysis of mean stature, body mass, limb proportion indices, and sexual dimorphism among 407 skeletally mature men and women from foraging and farming populations spanning the Late Mesolithic through Early Medieval periods in Central/Southeast Europe (~7100 calBC to 850 AD). Results document significantly reduced mean stature, body mass, and crural index in Neolithic agriculturalists relative both to Late Mesolithic hunter-gatherer-fishers and to later farming populations. This indication of relative growth impairment in the Neolithic, particularly among women, is supported by existing evidence of high developmental stress, intensive physical activity, and variable access to animal protein in these early agricultural populations. Among subsequent agriculturalists, temporal increases in mean stature, body mass, and crural index were more pronounced among Central European women, driving declines in the magnitude of sexual dimorphism through time. Overall, results suggest that the transition to agriculture in Central/Southeast Europe was challenging for early farming populations, but was followed by gradual amelioration across thousands of years, particularly among Central European women. This sex difference may be indicative, in part, of greater temporal variation in the social status afforded to young girls, in their access to resources during growth, and/or in their health status than was experienced by men.Grant sponsorship Cambridge Commonwealth, European and International Trust (UK; AAM), Social Sciences and Humanities Research Council (Canada; AAM), European Research Council (RP; ERC Starting Grant, ERC-2010-StG263441), Natural Environment Research Council (JTS; NERC Grant Number NE/M/S/2003/00069).This is the final version of the article. It first appeared from PLOS via http://dx.doi.org/10.1371/journal.pone.014846
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