693 research outputs found
Eigen-transitions in cantilever cylindrical shells subjected to vertical edge loads
A thin cantilever cylindrical shell subjected to a transverse shear force at the free end can experience two distinct modes of buckling, depending on its relative thickness and length. If the former parameter is fixed then a short cylinder buckles in a diffuse manner, while the eigenmodal deformation of a moderately long shell is localised, both axially and circumferentially, near its fixed end. Donnelltype buckling equations for cylindrical shells are here coupled with a non-symmetric membrane basic state to produce a linear boundary-value problem that is shown to capture the transition between the aforementioned instability modes. The main interest lies in exploring the approximate asymptotic separation of the independent variables in the corresponding stability equations, when the eigen-deformation is doubly localised. Comparisons with direct numerical simulations of the full buckling problem provide further insight into the accuracy and limitations of our approximations
On the Possibility of Measuring the Gravitomagnetic Clock Effect in an Earth Space-Based Experiment
In this paper the effect of the post-Newtonian gravitomagnetic force on the
mean longitudes of a pair of counter-rotating Earth artificial satellites
following almost identical circular equatorial orbits is investigated. The
possibility of measuring it is examined. The observable is the difference of
the times required to in passing from 0 to 2 for both senses of
motion. Such gravitomagnetic time shift, which is independent of the orbital
parameters of the satellites, amounts to 5 s for Earth; it is
cumulative and should be measured after a sufficiently high number of
revolutions. The major limiting factors are the unavoidable imperfect
cancellation of the Keplerian periods, which yields a constraint of 10
cm in knowing the difference between the semimajor axes of the satellites,
and the difference of the inclinations of the orbital planes which, for
, should be less than . A pair of spacecrafts
endowed with a sophisticated intersatellite tracking apparatus and drag-free
control down to 10 cm s Hz level might allow to meet
the stringent requirements posed by such a mission.Comment: LaTex2e, 22 pages, no tables, 1 figure, 38 references. Final version
accepted for publication in Classical and Quantum Gravit
The Nuclear Regulatory Commission\u27s Proposed Rulemaking on the Storage and Disposal of Nuclear Waste--The Case for Confidence Concerning Spent Fuel Storage
IMMUNOLOGICAL MEMORY IN VITRO
The immune responses to sheep erythrocytes of mouse spleen cell suspensions from immune and nonimmune donors were compared in vitro. In vivo immunity was only transiently reflected in vitro, and 8 wk after in vivo immunization the responses of cultures from immunized and nonimmunized mice were virtually identical. There appeared to be two mechanisms for an antibody response to sheep erythrocytes. The first was responsible for the early primary response and is unmodified in the immune animal though contributing little to subsequent in vivo responses due to its suppressibility by specific antibody. The second was expressed in the in vivo secondary response but not on in vitro challenge of spleen cells from mice immunized many weeks previously; spleen cell cultures from such immune mice, freed from the antibody of the in vivo environment, once again demonstrate a pure primary-type response
Representation of Clients in Matters Relating to Hospital Bills
This article is designed to acquaint Legal Services attorneys with a range of government health programs for which their clients may be eligible, and a number of legal theories that may impose a duty to provide care on public or private medical care institutions. The primary objective is to provide background material to assist the attorney in getting medical bills paid or defending a collection action. The article also includes a discussion of legal duties to provide care that will be useful in advising clients and consumer groups of their rights and of the programs and services that should be available in the community
Representation of Clients in Matters Relating to Hospital Bills
This article is designed to acquaint Legal Services attorneys with a range of government health programs for which their clients may be eligible, and a number of legal theories that may impose a duty to provide care on public or private medical care institutions. The primary objective is to provide background material to assist the attorney in getting medical bills paid or defending a collection action. The article also includes a discussion of legal duties to provide care that will be useful in advising clients and consumer groups of their rights and of the programs and services that should be available in the community
Experimental Verification of Ocean Bounced GPS Signals and Analysis of their Application to Ionospheric Corrections for Satellite Altimetry
An algorithm is presented which uses observations of Global Positioning System (GPS) signals reflected from the ocean surface and acquired by a GPS receiver onboard an altimetric satellite to compute the ionospheric delay present in the altimeter measurement. This eliminates the requirement for a dual frequency altimeter for many Earth observing missions. A ground-based experiment is described which confirms the presence of these ocean-bounced signals and demonstrates the potential for altimeter ionospheric correction at the centimeter level
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