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AmbieSense: a system and reference architecture for personalised and context-sensitive information services for mobile users
The purpose of AmbieSense is to provide personalised, context-sensitive information to the mobile user. It is about augmenting digital information to physical objects, rooms, and areas. The aim is to provide relevant information to the right user and situation. Digital content is distributed from the surroundings and onto your mobile phone. An ambient information environment is provided by a combination of context tag technology, a software platform to manage and deliver the information, and personal computing devices to which the information is served. This paper describes how the AmbieSense reference architecture has been defined and used in order to deliver information to the mobile citizen at the right time, place and situation. Information is provided via specialist content providers. The application area addresses the information needs of travellers and tourists
Tangled Nature: A model of emergent structure and temporal mode among co-evolving agents
Understanding systems level behaviour of many interacting agents is
challenging in various ways, here we'll focus on the how the interaction
between components can lead to hierarchical structures with different types of
dynamics, or causations, at different levels. We use the Tangled Nature model
to discuss the co-evolutionary aspects connecting the microscopic level of the
individual to the macroscopic systems level. At the microscopic level the
individual agent may undergo evolutionary changes due to mutations of
strategies. The micro-dynamics always run at a constant rate. Nevertheless, the
system's level dynamics exhibit a completely different type of intermittent
abrupt dynamics where major upheavals keep throwing the system between
meta-stable configurations. These dramatic transitions are described by a
log-Poisson time statistics. The long time effect is a collectively adapted of
the ecological network. We discuss the ecological and macroevolutionary
consequences of the adaptive dynamics and briefly describe work using the
Tangled Nature framework to analyse problems in economics, sociology,
innovation and sustainabilityComment: Invited contribution to Focus on Complexity in European Journal of
Physics. 25 page, 1 figur
Nitrous oxide emission from a range of land uses across Europe
International audienceThe results of a literature study examining quantitative estimates of N2O emission rates are presented for a range of land-uses across Europe. The analysis shows that the highest N2O emission rates are for agricultural lands compared to forests and grasslands. The main factors regulating these rates are available mineral nitrogen, soil temperature, soil water content and the available labile organic compounds. These controls operate across different time-scales, all must exceed a certain threshold for N2O emission to occur. The results support the need for an emission factor function of land-use and climate within models describing nitrogen dynamics in catchments. This would allow the assessment of the net N2O emission within catchments in terms of current levels and potential changes associated with climate variability, climate change and land use change. Keywords: nitrous oxide, soil water content, inorganic N, soil temperature, ecosystems, land-use management, soil typ
Macroscopic anomalies before the September 2010 M = 7.1 earthquake in
Abstract. Previous published work after the Kobe andİzmit earthquakes (1995 and 1999, respectively) demonstrated some reported meteorological and animal behaviour precursors were valid. Predictions were freshly tested for the Christchurch earthquake (M = 7.1, 4 September 2010). An internet survey with nearly 400 valid replies showed relative numbers of reports in precursor categories the day before the quake, were statistically significantly different from those in the preceding three days (excess meteorological events and animal behaviour). The day before the quake, there was also altered relative precursor class occurrence within 56 km compared with further away. Both these confirmed the earlier published work. Owners were woken up by unique pet behaviour 12 times as often in the hour before the quake compared with other hours immediately before (statistically highly significant). Lost and Found pet reports were double normal the week before, and 4.5 times normal both the day before the quake, and 9 days before. (Results were again statistically significant). Unique animal behaviour before the quake was often repeated before the numerous aftershocks. These pet owners claimed an approximate 80 % prediction reliability. However, a preliminary telephone survey suggested that animals showing any precursor response are a minority. Some precursors seem real, but usefulness seemed mostly restricted to 7 cases where owners were in, or near, a place of safety through disruptive pet behaviour, and one in which owners were diverted by a pet from being struck by falling fixtures. For a later 22 February 2011 M = 6.3 quake no reports of escape through warning by pets were recorded, which raises serious questions whether such prediction is practically useful, because lives claimed saved are extremely low compared with fatalities. It is shown the lost-pet statistics dates, correspond to ionospheric anomalies recorded using the GPS satellite system and geomagnetic disturbance data, and claimed as precursory. The latter more objective measurements may be the way of the future, but improved statistical treatment should include observations over longer periods of time without earthquakes
Variational multiparticle-multihole configuration mixing method applied to pairing correlations in nuclei
Applying a variational multiparticle-multihole configuration mixing method
whose purpose is to include correlations beyond the mean field in a unified way
without particle number and Pauli principle violations, we investigate
pairing-like correlations in the ground states of Sn,Sn and Sn. The same effective nucleon-nucleon interaction namely, the D1S
parameterization of the Gogny force is used to derive both the mean field and
correlation components of nuclear wave functions. Calculations are performed
using an axially symetric representation. The structure of correlated wave
functions, their convergence with respect to the number of particle-hole
excitations and the influence of correlations on single-particle level spectra
and occupation probabilities are analyzed and compared with results obtained
with the same two-body effective interaction from BCS, Hartree-Fock-Bogoliubov
and particle number projected after variation BCS approaches. Calculations of
nuclear radii and the first theoretical excited states are compared with
experimental data.Comment: 25 pages 21 figures. accepted for publication in Physical Review
dfpk : An R-package for Bayesian dose-finding designs using Pharmacokinetics (PK) for phase I clinical trials
Background and objective
Dose-finding, aiming at finding the maximum tolerated dose, and pharmacokinetics studies are the first in human studies in the development process of a new pharmacological treatment. In the literature, to date only few attempts have been made to combine pharmacokinetics and dose-finding and to our knowledge no software implementation is generally available. In previous papers, we proposed several Bayesian adaptive pharmacokinetics-based dose-finding designs in small populations. The objective of this work is to implement these dose-finding methods in an R package, called dfpk.
Methods
All methods were developed in a sequential Bayesian setting and Bayesian parameter estimation is carried out using the rstan package. All available pharmacokinetics and toxicity data are used to suggest the dose of the next cohort with a constraint regarding the probability of toxicity. Stopping rules are also considered for each method. The ggplot2 package is used to create summary plots of toxicities or concentration curves.
Results
For all implemented methods, dfpk provides a function (nextDose) to estimate the probability of efficacy and to suggest the dose to give to the next cohort, and a function to run trial simulations to design a trial (nsim). The sim.data function generates at each dose the toxicity value related to a pharmacokinetic measure of exposure, the AUC, with an underlying pharmacokinetic one compartmental model with linear absorption. It is included as an example since similar data-frames can be generated directly by the user and passed to nsim.
Conclusion
The developed user-friendly R package dfpk, available on the CRAN repository, supports the design of innovative dose-finding studies using PK information
Mind the gap? The persistence of pathological discourses in urban regeneration policy
Urban regeneration policy has historically framed policy problems using a discourse that pathologises areas and spatial communities. Since 2001 in England, and 2002 in Scotland a structural change in policy has occurred where citywide partnerships are now meant overcome structural spatial inequalities, countering pathological explanations. This paper uses historical and discourse analysis to evaluate one of the major community regeneration strategies developed by the Scottish Executive in 2002: Better Communities in Scotland: Closing the Gap. It seeks to ask whether structural change in policy was paralleled by discursive change; what discursive path dependence is evidenced? The text is placed in the historic context of UK urban renewal policies dating back to the launch of the Urban Programme in 1968 and particularly the policy discourse created by the influential Conservative government policy of 1988 New Life for Urban Scotland and the wider discourses of poverty and neighbourhood renewal policy created by Labour governments since 1997. The close textual analysis of the text shows that Better Communities in Scotland continues to pathologise spatial communities. Although this suggests a degree of historical path dependency, the historic breadth of the analysis also problematises simple historical determinism
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