146,122 research outputs found
A Bayesian localised conditional auto-regressive model for estimating the health effects of air pollution
Estimation of the long-term health effects of air pollution is a challenging task, especially when modeling spatial small-area disease incidence data in an ecological study design. The challenge comes from the unobserved underlying spatial autocorrelation structure in these data, which is accounted for using random effects modeled by a globally smooth conditional autoregressive model. These smooth random effects confound the effects of air pollution, which are also globally smooth. To avoid this collinearity a Bayesian localized conditional autoregressive model is developed for the random effects. This localized model is flexible spatially, in the sense that it is not only able to model areas of spatial smoothness, but also it is able to capture step changes in the random effects surface. This methodological development allows us to improve the estimation performance of the covariate effects, compared to using traditional conditional auto-regressive models. These results are established using a simulation study, and are then illustrated with our motivating study on air pollution and respiratory ill health in Greater Glasgow, Scotland in 2011. The model shows substantial health effects of particulate matter air pollution and nitrogen dioxide, whose effects have been consistently attenuated by the currently available globally smooth models
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A multi-agent system to support location based group decision making in mobile teams
This paper describes an agent-based approach for developing a location-based asynchronous group decision-support system for
mobile teams. The approach maximises the use of reusable service components (GSCmas â generic service component for
multi-agent systems) as the main interaction mechanism between agents to allow flexible support of a new group-decision
process. The paper describes the architecture of a GSCmas and provides details of how the GSCmas is integrated within a decision
support system. Finally a system (mPower) based on the proposed approach is introduced and applied to a location-based group
decision problem
Minimal gauge origin of baryon triality and flavorful signatures at the LHC
Baryon triality (B3) is a Z3 discrete symmetry that can protect the proton
from decay. Although its realization does not require supersymmetry, it is
particularly appealing in the supersymmetry as an alternative to the popular
R-parity. We discuss the issues in gauging B3, and present the minimal
supersymmetric model with B3 as the remnant discrete symmetry of a TeV scale
U(1) gauge symmetry. A flavor-dependent U(1) charge is necessary to achieve
this, and it results in very distinguishable and flavorful predictions for the
LHC experiments. We find a complementarity between a 2-lepton sneutrino
resonance and a 4-lepton Z' resonance in the supersymmetry search. In addition,
we introduce baryon tetrality (B4), which would play an equivalent role if
there are four fermion generations.Comment: Version to appear in PL
Bound on Z' Mass from CDMS II in the Dark Left-Right Gauge Model II
With the recent possible signal of dark matter from the CDMS II experiment,
the Z' mass of a new version of the dark left-right gauge model (DLRM II) is
predicted to be at around a TeV. As such, it has an excellent discovery
prognosis at the operating Large Hadron Collider.Comment: 11 page
A low cost air hybrid concept
This article is a pre-print version of the full and final article which is available at the link below.Copyright © 2010 Institut français du pétrole
Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made
or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than IFP must be honored. Abstracting with credit is permitted. To copy otherwise, to republish, to post on servers, or to redistribute to lists, requires prior specific permission and/or a fee: Request permission from Documentation, Institut français du pétrole, fax. +33 1 47 52 70 78, or [email protected] air hybrid engine absorbs the vehicle kinetic energy during braking, stores it in an air tank in the form of compressed air, and reuses it to propel a vehicle during cruising and acceleration. Capturing, storing and reusing this braking energy to give additional power can therefore improve fuel economy, particularly in cities and urban areas where the traffic conditions involve many stops and starts. In order to reuse the residual kinetic energy, the vehicle operation consists of 3 basic modes, i.e. Compression Mode (CM), Expander Mode (EM) and normal firing mode. Unlike previous works, a low cost air hybrid engine has been proposed and studied. The hybrid engine operation can be realised by means of production technologies, such as VVT and valve deactivation. In this work, systematic investigation has been carried out on the performance of the hybrid engine concept through detailed gas dynamic modelling using Ricardo WAVE software. Valve timing optimization has been done for the more efficient operation of air hybrid operation and obtaining higher braking and Motoring mean effective pressure for CM and EM respectively.EPSR
Generalized Lepton Number and Dark Left-Right Gauge Model
In a left-right gauge model of particle interactions, the left-handed fermion
doublet (nu,e)_L is connected to its right-handed counterpart (n,e)_R through a
scalar bidoublet so that e_L pairs with e_R, and nu_L with n_R to form mass
terms. Suppose the latter link is severed without affecting the former, then
n_R is not the mass partner of nu_L, and as we show in this paper, becomes a
candidate for dark matter which is relevant for the recent PAMELA and ATIC
observations. We accomplish this in a specific nonsupersymmetric model, where a
generalized lepton number can be defined, so that n_R and W_R are odd under R =
(-1)^{3B+L+2j}. Fermionic leptoquarks are also predicted.Comment: Version to appear in PRD (Rapid Communication
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