22,713 research outputs found
A-D-E Polynomial and Rogers--Ramanujan Identities
We conjecture polynomial identities which imply Rogers--Ramanujan type
identities for branching functions associated with the cosets , with
=A \mbox{}, D ,
E . In support of our conjectures we establish the correct
behaviour under level-rank duality for =A and show that the
A-D-E Rogers--Ramanujan identities have the expected asymptotics
in terms of dilogarithm identities. Possible generalizations to arbitrary
cosets are also discussed briefly.Comment: 19 pages, Latex, 1 Postscript figur
The stability of new transparent polymeric materials: The epoxy trimethoxyboroxine system. Part 1: The preparation, characterization and curing of epoxy resins and their copolymers
The effects of resin composition, curing conditions fillers, and flame retardant additives on the flammability of diglycidyl ether of bisphenol-A (DGEBA) as measured by the oxygen index is examined. The oxygen index of DGEBA cured with various curing agents was between 0.198 to 0.238. Fillers and flame retardant additives can increase the oxygen index dependent on the material and the amount used. Changes in the basic cured resin properties can be anticipated with the addition of noncompatible additives. High flame resistant epoxy resins with good stability and mechanical properties are investigated
Density regulation in strictly metric-free swarms
There is now experimental evidence that nearest-neighbour interactions in
flocks of birds are metric free, i.e. they have no characteristic interaction
length scale. However, models that involve interactions between neighbours that
are assigned topologically are naturally invariant under spatial expansion,
supporting a continuous reduction in density towards zero, unless additional
cohesive interactions are introduced or the density is artificially controlled,
e.g. via a finite system size. We propose a solution that involves a
metric-free motional bias on those individuals that are topologically
identified to be on an edge of the swarm. This model has only two primary
control parameters, one controlling the relative strength of stochastic noise
to the degree of co-alignment and another controlling the degree of the
motional bias for those on the edge, relative to the tendency to co-align. We
find a novel power-law scaling of the real-space density with the number of
individuals N as well as a familiar order-to-disorder transition
AFES Miscellaneous Publication 2010-02
Research has been conducted since 2001 to assist growers
in identifying components of peony field cut flower production
and distribution from field selection and planting to post harvest
handling and packaging for export. This experiment addressed
three components of the production cycle: field planting dates,
root quality and plant productivity, and post harvest handling
of cut stems. In a comparison of planting times (autumn, spring
or as containerized plants in mid summer), ‘Sarah Bernhardt’
and ‘Felix Crouse’ showed no difference in shoot number and
growth one full year after planting. ‘Duchess de Nemours’ and
‘Alexander Fleming’ showed significant reductions in growth
compared to the other cultivars, and we suspect disease rather
than planting time as the problem. All treatments where bud
break had occurred in storage with ‘Duchess de Nemours’ and
‘Alexander Fleming,’ new shoots rotted, and recovery was slow. A
treatment of elemental sulfur was not sufficient to protect roots
from storage rot.
‘Sarah Bernhardt’ roots and crown buds were weighed,
counted and measured prior to planting in order to learn if a
correlation exists between root quality and subsequent growth
and flowering. Three root attributes were correlated with the total
number of stems produced: total number of eyes per plant, total
number of roots per plant, and root fresh weight. Characteristics
such as root length and maximum diameter were not correlated
with subsequent growth. We found no relationship between
any root characteristics and the number of flowering stems
and foliage height in the first year. The attributes that showed correlation could not be fitted to a linear or curvilinear model
explaining the nature of the correlation. Larger sample sizes will
be necessary to clarify these relationships.
The best method for handling peony cut flowers for
greatest vase life is to cut peonies dry and store them dry in a
cooler (34°F) at 80+% relative humidity until shipping. Use of
water in buckets in the field or pulsing flowers with water in the
cooler does not improve vase life of peonies. Under optimum
conditions, ‘Sarah Bernhardt’ peonies lasted up to 15 days in a
vase, 8-9 days from bud break to full bloom, and an additional
5-6 days in full bloom. Chilling in a cooler is the most important
attribute to long vase life
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Do you pass it on? An examination of the consequences of perceived cyber incivility
Purpose: The emerging literature on computer-mediated communication at the study lacks depth in terms of elucidating the consequences of the effects of incivility on employees. This study aims to compare face-to-face incivility with incivility encountered via e-mail on both task performance and performance evaluation. Design/methodology/approach: In two experimental studies, the authors test whether exposure to incivility via e-mail reduces individual task performance beyond that of face-to-face incivility and weather exposure to that incivility results in lower performance evaluations for third-parties. Findings: The authors show that being exposed to cyber incivility does decrease performance on a subsequent task. The authors also find that exposure to rudeness, both face-to-face and via e-mail, is contagious and results in lower performance evaluation scores for an uninvolved third party. Originality/value: This research comprises an empirically grounded study of incivility in the context of e-mail at study, highlights distinctions between it and face-to-face rudeness and reveals the potential risks that cyber incivility poses for employees
The impact of the graduated driver licence scheme on road traffic accident youth mortality in New Zealand
This paper examines the impact of the introduction of New Zealand’s Graduated Driving Licence System (GDLS) on patterns of road traffic accident mortality amongst the young driving population from 1980 to 2001. Results show that the mortality rate has declined, but that rates in New Zealand are three times greater than in England and Wales and twice those of Scotland. When the data is adjusted to take account of differences in the minimum driving age, rates remain consistently higher in New Zealand and the proportional reduction in road traffic accident youth mortality is not significantly better than that experienced in Great Britain
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Learning Distributed Representations for Multiple-Viewpoint Melodic Prediction
The analysis of sequences is important for extracting in- formation from music owing to its fundamentally temporal nature. In this paper, we present a distributed model based on the Restricted Boltzmann Machine (RBM) for learning melodic sequences. The model is similar to a previous suc- cessful neural network model for natural language [2]. It is first trained to predict the next pitch in a given pitch se- quence, and then extended to also make use of information in sequences of note-durations in monophonic melodies on the same task. In doing so, we also propose an efficient way of representing this additional information that takes advantage of the RBM’s structure. Results show that this RBM-based prediction model performs better than previ- ously evaluated n-gram models and also outperforms them in certain cases. It is able to make use of information present in longer sequences more effectively than n-gram models, while scaling linearly in the number of free pa- rameters required
Effects on Amorphous Silicon Photovoltaic Performance from High-temperature Annealing Pulses in Photovoltaic Thermal Hybrid Devices
There is a renewed interest in photovoltaic solar thermal (PVT) hybrid
systems, which harvest solar energy for heat and electricity. Typically, a main
focus of a PVT system is to cool the photovoltaic (PV) cells to improve the
electrical performance, however, this causes the thermal component to
under-perform compared to a solar thermal collector. The low temperature
coefficients of amorphous silicon (a-Si:H) allow for the PV cells to be
operated at higher temperatures and are a potential candidate for a more
symbiotic PVT system. The fundamental challenge of a-Si:H PV is light-induced
degradation known as the Staebler-Wronski effect (SWE). Fortunately, SWE is
reversible and the a-Si:H PV efficiency can be returned to its initial state if
the cell is annealed. Thus an opportunity exists to deposit a-Si:H directly on
the solar thermal absorber plate where the cells could reach the high
temperatures required for annealing.
In this study, this opportunity is explored experimentally. First a-Si:H PV
cells were annealed for 1 hour at 100\degreeC on a 12 hour cycle and for the
remaining time the cells were degraded at 50\degreeC in order to simulate
stagnation of a PVT system for 1 hour once a day. It was found that, when
comparing the cells after stabilization at normal 50\degreeC degradation, this
annealing sequence resulted in a 10.6% energy gain when compared to a cell that
was only degraded at 50\degreeC
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Possible crater-based pingos, paleolakes and periglacial landscapes in the high latitudes of Utopia Planitia, Mars
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