497 research outputs found
Hamilton-Jacobi theory for optimal control problems on stratified domains
This thesis studies optimal control problems on stratified domains. We first establish a known proximal Hamilton-Jacobi characterization of the value function for problems with Lipschitz dynamics. This background gives the motivation for our results for systems over stratified domains, which is a system with non-Lipschitz dynamics that were introduced by Bressan and Hong. We provide an example that shows their attempt to derive a Hamilton-Jacobi characterization of the value function is incorrect, and discuss the nature of their error. A new construction of a multifunction is introduced that possesses properties similar to those of a Lipschitz multifunction, and is used to establish Hamiltonian criteria for weak and strong invariance. Finally, we use these characterizations to show that the minimal time function and the value function for a Mayer problem, both over stratified domains, satisfy and are the unique solutions to a proximal Hamilton-Jacobi equation
Notes on actinomycosis, and its transmissibility to the human subject
I refer to the question of the transmissibility of
some bovine diseases to human beings by the consumption of
the meat of diseased animals.
The primary object of my paper is to show that there is
prevalent amongst the cattle in Tasmania, as well as in the
adjacent colonies, from which we obtain a large proportion of
our meat supply, a disease which resembles tuberculosis in
some respects, but differs from it in the specific micro-organism
that is the cause of the disease, and yet, like tuberculosis, is
transmissible to the human subject, and is almost as
distressing in its consequences.
Soon after the publication of the discovery of the
actinomyces or ray-fungus iu diseased cattle, the same
vegetable parasite was found in man; and it was then seen
that the tumours in the bovine species presented great
similarity to those found in the human subject, leading to the
presumption that it was identically the same disease.
It has been shown by experiment that the introduction of
the fungus by inoculation into a calf has produced swellings
which contained the characteristic clubs of the fungus, thus
suggesting that this disease can be transmitted by direct
inoculation.
Many similar experiments have been made with a view to
prove the transmissibility of this vegetable parasite from
animal to animal, and in the majority of cases with a positive
result
X-ray generation from and spectroscopy of a thin liquid sheet
In this thesis a fan spray nozzle design is presented that is capable of producing single micrometer thick sheets of liquid, which are stable and flat. These sheets are characterised by various interferometric techniques, and some elementary fluid dynamics calculations are employed to understand the formation of the sheet. A new experimental vacuum chamber was designed and built, and the liquid sheet jet apparatus was installed into it and run successfully in the vacuum. Soft X-ray absorption measurements were attempted, but due to problems with a lack of X-ray flux and contamination of the experimental apparatus no results have yet been obtained. The sheet was also used as a source for high harmonic generation, generating harmonics up to 50\,eV. The mechanism of high harmonic generation in the liquid is investigated, with the conclusion being reached that it is a similar mechanism to the semi-classical three step model. The effects of scattering are considered, and found to be less severe than anticipated due to correlation effects in the condensed phase.Open Acces
Positioning for Trade Liberalization: Structure of Earnings, Comparative and Competitive Advantage of Agricultural Households in the United States and Canada
Consumer/Household Economics, International Relations/Trade,
The Distribution of X-ray Dips with Orbital Phase in Cygnus X-1
We present results of a comprehensive study of the distribution of absorption
dips with orbital phase in Cygnus X-1. Firstly, the distribution was obtained
using archival data from all major X-ray observatories and corrected for the
selection effect that phase zero (superior conjunction of the black hole) has
been preferentially observed. Dip occurrence was seen to vary strongly with
orbital phase \phi, with a peak at \phi ~ 0.95, i.e. was not symmetric about
phase zero. Secondly, the RXTE ASM has provided continuous coverage of the Low
State of Cygnus X-1 since Sept. 1996, and we have selected dip data based on
increases in hardness ratio. The distribution, with much increased numbers of
dip events, confirms that the peak is at \phi ~ 0.95, and we report the
discovery of a second peak at \phi ~ 0.6. We attribute this peak to absorption
in an accretion stream from the companion star HDE 226868. We have estimated
the ionization parameter at different positions showing that radiative
acceleration of the wind is suppressed by photoionization in particular regions
in the binary system. To obtain the variation of column density with phase, we
make estimates of neutral wind density for the extreme cases that acceleration
of the wind is totally suppressed, or not suppressed at all. An accurate
description will lie between these extremes. In each case, a strong variation
of column density with orbital phase resulted, similar to the variation of dip
occurrence. This provides evidence that formation of the blobs in the wind
which lead to absorption dips depends on the density of the neutral component
in the wind, suggesting possible mechanisms for blob growth.Comment: 9 pages, Latex, 7 ps figures. accepted by MNRA
Preliminary study of possible power development on the Gasconade River
The location of a possible dam site on the Gasconade River as a thesis proved to be a very interesting subject. Our first trip pointed out to us that we had undertaken a large task. We also realized that our subject was too big to complete thouroughly sic in the time alloted. Due to this circumstance we tried to cover the essential facts and to eliminate as much of the detail work as possible. For instance, we made no attempt to make a complete survey of the basin, instead, we ran surveys for some distance up the river to give an idea of the nature of the country and a way of approximating the volume of the basin --Foreword, Page 3
Christmas books
Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 2012Fecha de publ. tomada de WWW British Library cat
Notes relating to certain fossil leaves and fruits found in the auriferous drifts of Gulgong, New South Wales
The few specimens of Palaeontological Botany I am sending
to the Museum of the Royal Society, Tasmania (kindly
forwarded by my father), are complementary to the fossil
seed-vessels or fruits presented by me to the Museum some
eighteen months back. They all were obtained from the
same "lead," or auriferous drift, in the immediate neighbourhood
of Gulgong, at a depth of about 146 feet. This ancient
watercourse, called the "Black Lead," from containing dark
ligneous clay amongst its strata, has been worked for fully a mile in length, and was found very rich in gold. The
overlying strata consist of alluvial soil of a rich volcanic
character—clay, gravel, and basalt. Of the latter, two
varieties are met with; one, the hard, close-grained, bluish-black
stone; the other, called by miners "soft basalt," from
its friable, earthy nature, and derived from the hard variety
by decomposition
Auriferous country and gold-bearing rocks
The subject of my paper is one that cannot fail to prove of
interest to this Society, seeing the great importance the goldmining
industry is assuming, and has already assumed, in the
colony of Tasmania.
The advantages to be gained by fostering this industry in the
colony need scarcely be dilated upon by me, as they are so patent
to any one who will take the trouble to examine into the causes
of the vast progress the Eastern colonies of Australia have
made during the past quarter century. The numerous large
towns and villages that dot this portion of the continent
—the majority of them founded upon, or connected in some way
with, the discovery of gold in their immediate neighbourhood—
speak for themselves; and the immense impetus to
trade, commerce, and immigration which it brings about
shows what mining will do for a country, hitherto in a state
of almost primeval solitude. But for this source of wealth,
the major portion of these colonies would still have remained
in a "state of nature"—one huge sheep run, with but a
sparse population and scattered country villages
The Ursinus Weekly, December 12, 1902
Impressions of the football season • A football player\u27s view • Football spirit • Football review • Blenheim • Defects of football • Financial statement • Clubs reorganize • Societies • YMCAhttps://digitalcommons.ursinus.edu/weekly/3067/thumbnail.jp
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