Reinforcement Learning Rules in a Repeated Game

This paper examines the performance of simple reinforcement learningalgorithms in a stationary environment and in a repeated game where theenvironment evolves endogenously based on the actions of other agents. Sometypes of reinforcement learning rules can be extremely sensitive to smallchanges in the initial conditions, consequently, events early in a simulationcan affect the performance of the rule over a relatively long time horizon.However, when multiple adaptive agents interact, algorithms that performedpoorly in a stationary environment often converge rapidly to a stableaggregate behaviors despite the slow and erratic behavior of individuallearners. Algorithms that are robust in stationary environments can exhibitslow convergence in an evolving environment.     

A comment on the influence of substrates on the superfluid density of thin helium-four films atT=0

The influence of substrate potentials on the superfluid density in thin films of ⁴ He atT=0 is discussed. Estimates indicate that an observabl large reduction in _s is to be expected.     

Estimating spine shape in lateral sleep positions using silhouette-derived body shape models

This study aims at evaluating spinal alignment during sleep by combining personalized human models with mattress indentation measurements. A generic surface model has been developed that can be personalized based on anthropometric parameters derived from silhouette extraction. Shape assessment of the personalized surface models, performed by comparison with 3-D surface scans of the trunk, showed a mean unsigned distance of 9.77 mm between modeled and scanned surface meshes. The surface model is combined with an inner skeleton model, allowing the model to simulate distinct sleep postures. An automatic fitting algorithm sets the appropriate degrees of freedom to position the model on the measured indentation according to the adopted sleep posture. Validation on lateral sleep positions showed good intraclass correlations (0.73–0.88) between estimated and measured angular spinal deformations, indicating that silhouette-derived body shape models provide a valuable tool for the unobtrusive assessment of spinal alignment during sleep.Relevance to industry: A common drawback of the available techniques to assess spinal deformation on bedding systems is that they interfere with the actual sleep process. The current study presents a novel method based on silhouette-derived body shape models in order to estimate spine shape during sleep unobtrusively.     

Participation of Danish and immigrant cleaners in a 1-year worksite intervention preventing physical deterioration

Worksite health promotion is seldom offered to workers who are low-educated and multi-ethnic, possibly due to an assumption that they are more reluctant to participate. Furthermore, little has been done to promote health at female-dominated workplaces. The main aim of this study was to investigate differences in participation among immigrant and Danish cleaners throughout a 1-year randomised controlled study tailored to cleaners and carried out in predominantly female workplaces. No significant differences in ethnicity were found in consent and participation throughout the 1-year intervention. Dropout was equally distributed among Danish and immigrant cleaners. This study indicates that a worksite health promotion intervention among a female-dominated, high-risk occupation such as cleaning can be equally appealing for Danes and immigrants. PRACTITIONER SUMMARY: This study provides insight about participation of Danish and immigrant cleaners in a worksite health promotion intervention in a predominantly female occupation. For attaining high participation and low dropout in future worksite health promotion interventions among cleaners, the intervention ought to not only target the ethnic background of the workers, but also to be specifically tailored to the job group.     

Implementation of physical coordination training and cognitive behavioural training interventions at cleaning workplaces--secondary analyses of a randomised controlled trial

This study evaluates the implementation of physical coordination training (PCT) and cognitive behavioural training (CBTr) interventions in a randomised controlled trial at nine cleaners' workplaces. Female cleaners (n = 294) were randomised into a PCT, a CBTr or a reference (REF) group. Both 12-week interventions were performed in groups guided by an instructor. Records were kept on intervention dose (adherence) unanticipated events at the work place (context) and quality of intervention delivery (fidelity). Participant adherence was 37% in the PCT and 49% in the CBTr interventions. Optimal implementation was reached by only 6% in PCT and 42% in the CBTr. Analysis of the barriers to successful implementation indicated that the intervention process is sensitive to unanticipated events. In order to succeed in improving the health of high-risk populations such as cleaners and to correctly interpret intervention effects, more research on implementation is needed. Trial registration: ISRCTN96241850. PRACTITIONER SUMMARY: Both physical coordination training and cognitive behavioural training are potential effective workplace interventions among low educated job groups with high physical work demands. However, thorough consideration should be given to feasibility in the design of interventions. The optimal intervention should be tailored to closely match the implementation context and be robust and flexible to minimise susceptibility to changes in work organisation.     

Gender identity: The benefits of a self-schema approach.

Questions S. L. Bem's (see record 1983-21087-001) definition of a gender schema and argues that male and female sex-typed individuals do not have equivalent gender schemata. The high-androgynous individuals are the only ones for whom both masculinity and femininity are equally available and who might be properly termed "gender schematic." (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermal explosion in a hot gas mixture with organic gel fuel droplets

Recent experimental evidence has uncovered the peculiar behavior of certain gel droplets which, under appropriate ambient thermal conditions, evaporate and burn in an oscillatory fashion. In this work a preliminary foray is made into the theoretical analysis of the nature of the evolution of a hot gas mixture containing organic gel fuel droplets with oscillatory evaporation within the context of thermal-explosion theory. The problem is modeled as a system of highly nonlinear singularly perturbed ordinary differential equations. Non-dimensionalization of the equations enables identification of the parameters that play a major role in determining the dynamical regimes of the system of equations. The method of integral manifolds is exploited for the analysis and it is found, that for certain parametric regions, the system exhibits new dynamical behavior that is quite different from that found for conventional liquid droplets.     

THE IMPACT OF SPATIAL VERSUS ECONOMIC MEASURES IN AN URBAN TRANSPORTATION PLAN

A multimodal model for traffic was developed by the Flemish administration. For the first time an integrated set of measures was taken into account to forecast statistics on car-traffic and the use of public transport systems during evening peak-hours. The measures can be classified in four groups: planning, infrastructure, regulation and financial. Each input is forecasted for 2010 by means of two opposite scenarios: a trend scenario and a policy (sustainable) scenario. The model was first tested for the Antwerp region on a very detailed geographical level. We sought to identify which measures had a significant influence on the results. As a result of a sensitivity analysis we conclude that even in the long run planning measures are least effective, followed by infrastructure measures that may stimulate local people to make use of public transport. Regulatory measures and especially financial measures have clearly the most significant impact on generation of passenger kilometres and modal choice during the evening rush hour.     

The face of the patent is not the “Whole Story”: determining effective life of a pharmaceutical patent in the United States

This article provides an overview of the factors that may contribute to the effective term of protection for a pharmaceutical product in the USA––by patent and by FDA market exclusivities, identifies public and commercial sources for collecting relevant patent term and exclusivity data, and provides a strategy for ensuring that the effective term of protection has been calculated accurately.     

Evaluating the Endophenotype Model of ADHD Neuropsychological Deficit: Results for Parents and Siblings of Children With ADHD Combined and Inattentive Subtypes.

Neurogenetic models predict neuropsychological weaknesses in the relatives of children with attention-deficit/ hyperactivity disorder (ADHD). The authors examined executive and regulatory measures in 386 relatives (307 parents, 79 siblings) of children with ADHD combined type, ADHD inattentive type, and controls. Predicted deficits were seen on trailmaking (relatives of ADHD combined type only), stop-signal reaction times (relatives of girls only), and response variability (mothers only) but not on naming or output speed. Effects generally held, even with relatives' ADHD status controlled. A neuropsychologically impaired subgroup of children with ADHD had relatives with clear neuropsychological weaknesses. The authors conclude that a neurogenetic model of ADHD etiology is supportable only for a subset of executive functions and that neuropsychological heterogeneity warrants more examination in ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)