2,108 research outputs found
Psychological Issues in Online Adaptive Task Allocation
Adaptive aiding is an idea that offers potential for improvement over many current approaches to aiding in human-computer systems. The expected return of tailoring the system to fit the user could be in the form of improved system performance and/or increased user satisfaction. Issues such as the manner in which information is shared between human and computer, the appropriate division of labor between them, and the level of autonomy of the aid are explored. A simulated visual search task was developed. Subjects are required to identify targets in a moving display while performing a compensatory sub-critical tracking task. By manipulating characteristics of the situation such as imposed task-related workload and effort required to communicate with the computer, it is possible to create conditions in which interaction with the computer would be more or less desirable. The results of preliminary research using this experimental scenario are presented, and future directions for this research effort are discussed
Pilot interaction with automated airborne decision making systems
The use of advanced software engineering methods (e.g., from artificial intelligence) to aid aircraft crews in procedure selection and execution is investigated. Human problem solving in dynamic environments as effected by the human's level of knowledge of system operations is examined. Progress on the development of full scale simulation facilities is also discussed
The geography of strain: organizational resilience as a function of intergroup relations
Organizational resilience is an organization’s ability to absorb strain and preserve or
improve functioning, despite the presence of adversity. In existing scholarship there is
the implicit assumption that organizations experience and respond holistically to acute
forms of adversity. We challenge this assumption by theorizing about how adversity can
create differential strain, affecting parts of an organization rather than the whole. We
argue that relations among those parts fundamentally shape organizational resilience.
We develop a theoretical model that maps how the differentiated emergence of strain in
focal parts of an organization triggers the movements of adjoining parts to provide or
withhold resources necessary for the focal parts to adapt effectively. Drawing on core
principles of theories about intergroup relations, we theorize about three specific
pathways—integration, disavowal, and reclamation—by which responses of adjoining
parts to focal part strain shape organizational resilience. We further theorize about
influences on whether and when adjoining parts are likely to select different pathways.
The resulting theory reveals how the social processes among parts of organizations
influence member responses to adversity and, ultimately, organizational resilience. We
conclude by noting the implications for organizational resilience theory, research, and
practice.Accepted manuscrip
Pilot interaction with automated airborne decision making systems
Two project areas were pursued: the intelligent cockpit and human problem solving. The first area involves an investigation of the use of advanced software engineering methods to aid aircraft crews in procedure selection and execution. The second area is focused on human problem solving in dynamic environments, particulary in terms of identification of rule-based models land alternative approaches to training and aiding. Progress in each area is discussed
Optimal power generation using dark states in dimers strongly coupled to their environment
Dark state protection has been proposed as a mechanism to increase the power
output of light harvesting devices by reducing the rate of radiative
recombination. Indeed many theoretical studies have reported increased power
outputs in dimer systems which use quantum interference to generate dark
states. These models have typically been restricted to particular geometries
and to weakly coupled vibrational baths. Here we consider the
experimentally-relevant strong vibrational coupling regime with no geometric
restrictions on the dimer. We analyze how dark states can be formed in the
dimer by numerically minimizing the emission rate of the lowest energy excited
eigenstate, and then calculate the power output of the molecules with these
dark states. We find that there are two distinct types of dark states depending
on whether the monomers form homodimers, where energy splittings and dipole
strengths are identical, or heterodimers, where there is some difference.
Homodimers, which exploit destructive quantum interference, produce high power
outputs but strong phonon couplings and perturbations from ideal geometries are
extremely detrimental. Heterodimers, which are closer to the classical picture
of a distinct donor and acceptor molecule, produce an intermediate power output
that is relatively stable to these changes. The strong vibrational couplings
typically found in organic molecules will suppress destructive interference and
thus favour the dark-state enhancement offered by heterodimers.Comment: 20+18 pages, 5+5 figures. We have updated Figures 4, 5, F1 and G1 to
correct for a minor error, however the correction is small and does not
change the message of the paper. We have also added a paragraph to the
appendix to detail how the rotating wave approximation and double excited
state affect the master equatio
Analytic expression for the optical exciton transition rates in the polaron frame
Funding: D. M. R. acknowledges studentship funding from EPSRC (EP/L015110/1). B. W. L. and E.M. G. acknowledge support from EPSRC (Grants No. l EP/T014032/1 and No. EP/T01377X/1).When an optical emitter is strongly coupled to a vibrational bath the polaron transformation is often used to permit an accurate second-order Redfield master equation. However, the optical transition rates in the polaron frame are not analytic and approximations typically need to be made, which result in the loss of anything other than simple additive effects of the two baths. In this paper, we derive an intuitive analytic expression for the polaron frame optical transition rates by means of a finite-mode truncation of the vibrational bath. Using this technique, calculations of the transition rates converge for only a few modes in the truncated spectral d., and capture nonadditive effects such as population inversion of a two-level system.Publisher PDFPeer reviewe
The Genera and Species of Comatulidae (Comatulida: Crinoidea): Taxonomic Revisions and a Molecular and Morphological Guide
We provide a guide for identification of Comatulidae, a family of crinoid echinoderms, incorporating morphological and molecular evidence. A non-dichotomous key for all genera is included, as well as photographs of species most likely to be encountered in the tropical western Pacific Ocean. Based on sequencing of cytochrome oxidase subunit I (COI), and other genes when necessary, we identified four cases where taxonomic revision was needed. We synonymized Comaster nobilis under Comaster schlegelii, and Clarkcomanthus exilis under Clarkcomanthus comanthipinnus, and re-described Clarkcomanthus albinotus. We also showed the variation of COI sequences within and among species, which varies from lineage to lineage. In some cases, specimens with obvious morphological disparity possessed very little intraspecific molecular diversity (\u3c1%). In others, specimens with nearly identical external appearances exhibited quite divergent COI sequences (up to 6%). These results, combined with the non-dichotomous key herein, offer guidelines for identification and discussion of existing and new species of Comatulidae
Morphological Correlates of Mechanotransduction in Acousticolateral Hair Cells
The development of ideas on mechanotransduction in acousticolateral hair cells is described, leading to the current idea that transduction depends on deflection of the bundle of stereocilia by a force parallel to the plane of the sensory epithelium. Electrophysiological experiments are summarised, suggesting that transduction depends on a shear between the different rows of stereocilia, and that the transducer channels are situated towards the tips of the stereocilia. Analysis of the ways that shear between the rows of stereocilia could be detected suggests that tip links are the structures which are most likely to transmit the stimulus-induced forces to the transducer channels on the membrane. The directional selectivity of mechanotransduction is associated with the position of the kinocilium and gradation in heights of the stereocilia; evidence is presented suggesting that in the lateral line these are partly determined by the mitosis giving rise to the hair cell. Tip links differentiate out of links which initially join the stereocilia in all directions, with their final spatial organisation, which sets the directional selectivity of mechanotransduction, probably being determined by the gradient in growth of the stereocilia
Phenology satellite experiment
There are no author-identified significant results in this report
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