65,775 research outputs found
A national survey of in-service staff activities and projects in business education.
Thesis (M.Ed.)--Boston Universit
Macroscale boundary conditions for a non-linear heat exchanger
Multiscale modelling methodologies build macroscale models of materials with
complicated fine microscale structure. We propose a methodology to derive
boundary conditions for the macroscale model of a prototypical non-linear heat
exchanger. The derived macroscale boundary conditions improve the accuracy of
macroscale model. We verify the new boundary conditions by numerical methods.
The techniques developed here can be adapted to a wide range of multiscale
reaction-diffusion-advection systems
A Laboratory Infection of Alfalfa Weevil, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae), Larvae With the Fungal Pathogen \u3ci\u3eZoophthora Phytonomi\u3c/i\u3e (Zygomycetes: Entomophthoraceae)
Larvae of the alfalfa weevil, Hypera postica, were infected by an in vitro colony of Zoophthora phytonomi. Two spore types (infective conidia, and resting spores) were produced from infection trials. The spore type produced may be influenced by the physiological state of the larvae. Trials using field collected larvae which would produce diapausing adults formed both conidia and resting spores. Trials using larvae from a nondiapausing colony, however, formed only resting spores
Accurate macroscale modelling of spatial dynamics in multiple dimensions
Developments in dynamical systems theory provides new support for the
macroscale modelling of pdes and other microscale systems such as Lattice
Boltzmann, Monte Carlo or Molecular Dynamics simulators. By systematically
resolving subgrid microscale dynamics the dynamical systems approach constructs
accurate closures of macroscale discretisations of the microscale system. Here
we specifically explore reaction-diffusion problems in two spatial dimensions
as a prototype of generic systems in multiple dimensions. Our approach unifies
into one the modelling of systems by a type of finite elements, and the
`equation free' macroscale modelling of microscale simulators efficiently
executing only on small patches of the spatial domain. Centre manifold theory
ensures that a closed model exist on the macroscale grid, is emergent, and is
systematically approximated. Dividing space either into overlapping finite
elements or into spatially separated small patches, the specially crafted
inter-element/patch coupling also ensures that the constructed discretisations
are consistent with the microscale system/PDE to as high an order as desired.
Computer algebra handles the considerable algebraic details as seen in the
specific application to the Ginzburg--Landau PDE. However, higher order models
in multiple dimensions require a mixed numerical and algebraic approach that is
also developed. The modelling here may be straightforwardly adapted to a wide
class of reaction-diffusion PDEs and lattice equations in multiple space
dimensions. When applied to patches of microscopic simulations our coupling
conditions promise efficient macroscale simulation.Comment: some figures with 3D interaction when viewed in Acrobat Reader. arXiv
admin note: substantial text overlap with arXiv:0904.085
An Alternative to Using Fresh Alfalfa for Culturing \u3ci\u3eColias Philodice Eurytheme\u3c/i\u3e Boisduval (Lepidoptera: Pieridae)
Various artificial materials were implemented at each life stage of the alfalfa caterpillar, Colias philodice eurytheme Boisduval, to provide effective and economical replacements for alfalfa. Alfalfa substitutes were used for oviposition and feeding. We also developed a favorable laboratory mating environment. Also, the development of a method for removing disease organisms from eggs without increasing egg mortality was an essential facet of this work. The performance of individuals on artificial surfaces was compared with similar individuals reared on greenhouse alfalfa.
Green tape oriented at the top of oviposition cages or near some object which could be held on to while ovipositing was the most successful surface. Egg yields on green tape were comparable to those on alfalfa. A dilute bleach wash followed by two water washes required little time, yet provided adequate disease control, and all larval instars thrived on artificial diet. Methods for handling pupae and new adults and the favorable mating environment reduced colony maintenance time yet sumival rates insured propagation of the colony
- …