35,510 research outputs found
Predicting adaptive responses - simulating occupied environments
Simulation of building performance is increasingly being used in design practice to predict comfort of occupants in finished buildings. This is an area of great uncertainty: what actions does a person take when too warm or suffering from glare; how is comfort measured; how do groups of people interact to control environmental conditions, etc? An increasing attention to model these issues is evident in current research. Two issues are covered in this paper: how comfort can be assessed and what actions occupants are likely to make to achieve and maintain a comfortable status. The former issue describes the implementation of existing codes within a computational framework. This is non-trivial as information on local air velocities, radiant temperature and air temperature and relative humidity have to be predicted as they evolve over time in response to changing environmental conditions. This paper also presents a nascent algorithm for modelling occupant behaviour with respect to operable windows. The algorithm is based on results of several field studies which show the influence of internal and external temperatures on decision making in this respect. The derivation and implementation of the algorithm is discussed, highlighting areas where further effort could be of benefit
Alternatives to Kronig-Kramers Transformation and Testing, and Estimation of Distributions
Two alternatives to Kronig-Kramers analysis of small-signal ac immittance data are discussed and illustrated using both synthetic and experimental data. The first, a derivative method of approximating imaginary-part response from real-part data, is found to be too approximate in regions where the imaginary-part varies appreciably with frequency. The second, a distribution of relaxation-times fitting method, is shown to be valuable for testing whether a data set satisfies the Kronig-Kramers relations and so is associated with a system whose properties are time-invariant. It also is valuable for estimating real- or imaginary-part response from the other part, usually with small error. Unlike Kronig-Kramers analysis, the second method usually requires no extrapolation outside the range of the measured data. Finally, this discrete-function method also allows one to estimate the distribution of relaxation times or activation energies associated with a given set of frequency-response data. This application is described and illustrated for both synthetic and experimental data and is shown to yield good but somewhat approximate results for the estimation of continuous distributions. It is particularly valuable for identifying response regions arising from a continuous distribution and distinguishing them from those associated with discrete time-constant response
Healthcare services managers: what information do they need and use?
Objectives: To gain insight into the information behaviour of healthcare services managers as they draw on information while engaged in decision making unrelated to individual patient care. Objectives – The purpose of this research project was to gain insight into the information behaviour of healthcare services managers as they use information while engaged in decision-making unrelated to individual patient care.
Methods – This small-scale, exploratory, multiple case study used the critical incident technique in nineteen semi-structured interviews. Responses were analyzed using ‘Framework,’ a matrix-based content analysis system.
Results – This paper presents findings related to the internal information that healthcare services managers need and use. Their decisions are influenced by a wide variety of factors. They must often make decisions without all of the information they would prefer to have. Internal information and practical experience set the context for new research-based information, so they are generally considered first.
Conclusions – Healthcare services managers support decisions with both facts and value-based information. These results may inform both delivery of health library services delivery and strategic health information management planning. They may also support librarians who extend their skills beyond managing library collections and teaching published information retrieval skills, to managing internal and external information, teaching information literacy, and supporting information sharing
The Social Wasps (Hymenoptera: Vespidae) of Indiana
An updated taxonomic treatment of the social wasps (Hymenoptera: Vespidae) of Indiana is made. Illustrated identification keys are provided for species of Polistes, Vespa, Vespula, and Dolichovespula. New distributional records and biological notes are provided for each species
Measuring dopant concentrations in compensated p-type crystalline silicon via iron-acceptor pairing
We present a method for measuring the concentrations of ionized acceptors and donors in compensated p-type silicon at room temperature.Carrier lifetimemeasurements on silicon wafers that contain minute traces of iron allow the iron-acceptor pair formation rate to be determined, which in turn allows the acceptor concentration to be calculated. Coupled with an independent measurement of the resistivity and a mobility model that accounts for majority and minority impurity scatterings of charge carriers, it is then possible to also estimate the total concentration of ionized donors. The method is valid for combinations of different acceptor and donor species.D.M. is supported by an Australian Research Council
fellowship. L.J.G. would like to acknowledge SenterNovem
for support
Numerical Tests of the Chiral Luttinger Liquid Theory for Fractional Hall Edges
We report on microscopic numerical studies which support the chiral Luttinger
liquid theory of the fractional Hall edge proposed by Wen. Our calculations are
based in part on newly proposed and accurate many-body trial wavefunctions for
the low-energy edge excitations of fractional incompressible states.Comment: 12 pages + 1 figure, Revte
Generalised Calogero-Moser models and universal Lax pair operators
Calogero-Moser models can be generalised for all of the finite reflection
groups. These include models based on non-crystallographic root systems, that
is the root systems of the finite reflection groups, H_3, H_4, and the dihedral
group I_2(m), besides the well-known ones based on crystallographic root
systems, namely those associated with Lie algebras. Universal Lax pair
operators for all of the generalised Calogero-Moser models and for any choices
of the potentials are constructed as linear combinations of the reflection
operators. The consistency conditions are reduced to functional equations for
the coefficient functions of the reflection operators in the Lax pair. There
are only four types of such functional equations corresponding to the
two-dimensional sub-root systems, A_2, B_2, G_2, and I_2(m). The root type and
the minimal type Lax pairs, derived in our previous papers, are given as the
simplest representations. The spectral parameter dependence plays an important
role in the Lax pair operators, which bear a strong resemblance to the Dunkl
operators, a powerful tool for solving quantum Calogero-Moser models.Comment: 37 pages, LaTeX2e, no macro, no figur
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