10,624 research outputs found
Projected technological requirements for remote sensing of terrain variables
Contributions of remote sensing to hydrogeomorphology and terrain analysis are reviewed in order to identify characteristics that should receive support in system and sensor configuration planning. Fluvial morphological studies, peak discharge modeling, and hydrogeomorphic floodplain mapping using large scale (1:12,000) to small scale (1:750,000) orbital photography are discussed as well as quantitative assessment of terrain variables for specific applications
On relations between one-dimensional quantum and two-dimensional classical spin systems
We exploit mappings between quantum and classical systems in order to obtain
a class of two-dimensional classical systems with critical properties
equivalent to those of the class of one-dimensional quantum systems discussed
in a companion paper (J. Hutchinson, J. P. Keating, and F. Mezzadri,
arXiv:1503.05732). In particular, we use three approaches: the Trotter-Suzuki
mapping; the method of coherent states; and a calculation based on commuting
the quantum Hamiltonian with the transfer matrix of a classical system. This
enables us to establish universality of certain critical phenomena by extension
from the results in our previous article for the classical systems identified.Comment: 36 page
The magnetostriction of nikel and gadolinium
Nickel. An optical grid method has been used to check the anomaly in the λl00, T curve (Comer and Hunt 1955) in a nickel crystal. The results appeared to confirm the anomaly but as the method could not be calibrated independently there was considerable doubt about their accuracy. A solenoid capable of giving fields of 10,500 oersteds has been constructed, and magnetostriction measurements carried out using the capacitance bridge method of Corner and Hunt, on the [100] specimen in the temperature range 20 K to 630 K, and on the [111] specimen in the temperature range 78 K to 630 K, The results show that the λl00,T anomaly does not exist. Reasons are given for the error in the optical, grid method, and the results obtained by the capacitance bridge method are discussed in relation to those of Corner and Hunt, and to the theoretical equation of Vonsovsky (194-0). Extrapolation of the X,T curves to 0 K gives λlll = -28 x 10(^-6), λ100 = -57 x 10(^-6). Gadolinium. A zone melting apparatus has been constructed for the purpose of segregating the impurities in a piece of polycrystalline gadolinium in order to grow a single crystal. The grain size has been increased but no single crystal has been produced. Magnetostriction and intensity of magnetization measurements have been made on an ellipsoid of polycrystalline gadolinium in the temperature range 78 K to 350 K. The results show that gadolinium has a large volume effect, and the volume magnetostriction is proportional to the square of the paramagnetic magnetization above the Curie point. The saturation magnetization shows an anomaly at 150 K, and becomes zero at 233 K. The contribution of the volume magnetostriction to the thermal expansion of gadolinium is shown to be too small to account for the thermal expansion anomaly except in the immediate neighbourhood of the Curie point
A robust method for measurement of fluctuation parallel wavenumber in laboratory plasmas
Measuring the parallel wavenumber is fundamental for the experimental characterization of electrostatic instabilities. It becomes particularly important in toroidal geometry, where spatial inhomogeneities and curvature can excite both drift instabilities, whose wavenumber parallel to the magnetic field is finite, and interchange instabilities, which typically have vanishing parallel wavenumber. We demonstrate that multipoint measurements can provide a robust method for the discrimination between the two cases
High-throughput in-situ characterization and modelling of precipitation kinetics in compositionally graded alloys
The development of new engineering alloy chemistries is a time consuming and
iterative process. A necessary step is characterization of the
nano/microstructure to provide a link between the processing and properties of
each alloy chemistry considered. One approach to accelerate the identification
of optimal chemistries is to use samples containing a gradient in composition,
ie. combinatorial samples, and to investigate many different chemistries at the
same time. However, for engineering alloys, the final properties depend not
only on chemistry but also on the path of microstructure development which
necessitates characterization of microstructure evolution for each chemistry.
In this contribution we demonstrate an approach that allows for the in-situ,
nanoscale characterization of the precipitate structures in alloys, as a
function of aging time, in combinatorial samples containing a composition
gradient. The approach uses small angle x-ray scattering (SAXS) at a
synchrotron beamline. The Cu-Co system is used for the proof-of-concept and the
combinatorial samples prepared contain a gradient in Co from 0% to 2%. These
samples are aged at temperatures between 450{\textdegree}C and
550{\textdegree}C and the precipitate structures (precipitate size, volume
fraction and number density) all along the composition gradient are
simultaneously monitored as a function of time. This large dataset is used to
test the applicability and robustness of a conventional class model for
precipitation that considers concurrent nucleation, growth and coarsening and
the ability of the model to describe such a large dataset.Comment: Published in Acta Materiali
Medicine, Morality and Social Policy in Imperial Russia: The Early Years of the Alcoholism Commission
Interview with Scott Hutchinson by Andrea L’Hommedieu
Biographical NoteScott Frederick Hutchinson was born in Gardiner, Maine, on April 16, 1929, to Helen Frances and Scott Arthur Hutchinson. His mother was a homemaker, and his father was employed by New England Telephone Company, rising in the ranks from line worker to vice president. Scott’s childhood was spent living in various communities throughout New England. He attended Northeastern University, and after college served in the Army during the Korean War. Coming back to Maine, he began a career in banking. During Ken Curtis’ campaign for governor, he served as treasurer. He then served as treasurer for Ed Muskie’s senatorial campaigns, vice presidential campaign, and as treasurer for Muskie\u27s presidential primary race. He served as George Mitchell’s campaign treasurer.
SummaryInterview includes discussion of: working on Muskie’s staff with Mitchell in 1976; Maine gubernatorial campaign (1974); why Mitchell lost to Longley; Joe Angelone; Mitchell\u27s running for Senate majority leader; Mitchell’s 1982 reelection campaign; David Emery; Mitchell’s relationship with Bill Cohen; the role of Independents in Mitchell’s campaigns; campaign changes for Mitchell between 1974 and 1982; and Hutchinson’s reaction to Mitchell’s announcement of retirement
CONSTITUTIONAL LAW--DUE PROCESS AND THE BILL OF RIGHTS--SELF-INCRIMINATION
In the course of evolving workable doctrines which give substance and meaning to the skeletal phrase due process of law as used in the Fourteenth Amendment to limit state action, the Supreme Court has frequently been called on to determine the scope of the several prohibitions and guarantees of the Bill of Rights of the federal Constitution. This general problem, and more particularly the application of the Fifth Amendment self-incrimination clause to state criminal proceedings, was again presented in a recent case and resulted in a sharp division of opinion within the Court
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