3,536 research outputs found
A methodology for determining optimum microwave remote sensor parameters
There are no author-identified significant results in this report
A House of Cards: Free Banking in Antebellum Chicago
The Chicago free banking market of the antebellum period has more than once aroused the interest of historians and economists alike. Implemented in the state of Illinois in 1851, free banking was a common, though not universal occurrence in the United States at the time. The city of Chicago’s experience with free banking was anything but common, however. Within the first 18 months after the Illinois legislature enacted the Illinois Free Banking Law, 9 free banks had begun operation in Chicago and between them had an aggregate note issue of over 50,000 in circulation. Free banks in cities of comparable size had around 3.85.1 Those who have explored the subject have tended to focus on the bank wars or on the nature of free banking as a whole in their explanations, but neither of these explanations are entirely sufficient to explain the almost total lack of free banks in Chicago. Rather, a close examination of free banking in Chicago within the broader framework of Illinois free banking suggests that Chicago had what economist Andrew Economopoulos described as a shadow banking system.2
1Andrew Economopoulos, A Reappraisal of the Chicago Free Banking Market: Why so few Free Banks? (Collegeville: Ursinus College, 2016), pg. 1.
2Ibid
Radar studies related to the earth resources program
The radar systems research discussed is directed toward achieving successful application of radar to remote sensing problems in such areas as geology, hydrology, agriculture, geography, forestry, and oceanography. Topics discussed include imaging radar and evaluation of its modification, study of digital processing for synthetic aperture system, digital simulation of synthetic aperture system, averaging techniques studies, ultrasonic modeling of panchromatic system, panchromatic radar/radar spectrometer development, measuring octave-bandwidth response of selected targets, scatterometer system analysis, and a model Fresnel-zone processor for synthetic aperture imagery
Morphology of the Nuclear Disk in M87
A deep, fuly sampled diffraction limited (FWHM ~ 70 mas) narrow-band image of
the central region in M87 was obtained with the Wide Filed and Planetary Camera
2 of the Hubble Space Telescope using the dithering technique. The
H-alpha+[NII] continuum subtracted image reveals a wealth of details in the
gaseous disk structure described earlier by Ford et al. (1994). The disk
morphology is dominated by a well defined three-arm spiral pattern. In
addition, the major spiral arms contain a large number of small "arclets"
covering a range of sizes (0.1-0.3 arcsec = 10-30 pc). The overall surface
brightness profile inside a radius ~1.5" (100 pc) is well represented by a
power-law I(mu) ~ mu^(-1.75), but when the central ~40 pc are excluded it can
be equally well fit by an exponential disk. The major axis position angle
remains constant at about PA_disk ~ 6 deg for the innermost ~1", implying the
disk is oriented nearly perpendicular to the synchrotron jet (PA_jet ~ 291
deg). At larger radial distances the isophotes twist, reflecting the gas
distribution in the filaments connecting to the disk outskirts. The ellipticity
within the same radial range is e = 0.2-0.4, which implies an inclination angle
of i~35 deg. The sense of rotation combined with the dust obscuration pattern
indicate that the spiral arms are trailing.Comment: 5 pages, 3 postscript figures, to appear in the Proceedings of the
M87 Workshop, Ringberg castle, Germany, 15-19 Sep 1997, also available from
http://jhufos.pha.jhu.edu/~zlatan/papers.htm
Metallicity Distribution Functions of Four Local Group dwarf galaxies
We present stellar metallicities in Leo I, Leo II, IC 1613, and Phoenix dwarf
galaxies derived from medium (F390M) and broad (F555W, F814W) band photometry
using the Wide Field Camera 3 (WFC3) instrument aboard the Hubble Space
Telescope. We measured metallicity distribution functions (MDFs) in two ways,
1) matching stars to isochrones in color-color diagrams, and 2) solving for the
best linear combination of synthetic populations to match the observed
color-color diagram. The synthetic technique reduces the effect of photometric
scatter, and produces MDFs 30-50 % narrower than the MDFs produced from
individually matched stars. We fit the synthetic and individual MDFs to
analytical chemical evolution models (CEM) to quantify the enrichment and the
effect of gas flows within the galaxies. Additionally, we measure stellar
metallicity gradients in Leo I and II. For IC 1613 and Phoenix our data do not
have the radial extent to confirm a metallicity gradient for either galaxy.
We find the MDF of Leo I (dwarf spheroidal) to be very peaked with a steep
metal rich cutoff and an extended metal poor tail, while Leo II (dwarf
spheroidal), Phoenix (dwarf transition) and IC 1613 (dwarf irregular) have
wider, less peaked MDFs than Leo I. A simple CEM is not the best fit for any of
our galaxies, therefore we also fit the `Best Accretion Model' of Lynden-Bell
1975. For Leo II, IC 1613 and Phoenix we find similar accretion parameters for
the CEM, even though they all have different effective yields, masses, star
formation histories and morphologies. We suggest that the dynamical history of
a galaxy is reflected in the MDF, where broad MDFs are seen in galaxies that
have chemically evolved in relative isolation and narrowly peaked MDFs are seen
in galaxies that have experienced more complicated dynamical interactions
concurrent with their chemical evolution.Comment: 15 pages, 8 figures, accepted in A
Image synthesis for SAR system, calibration and processor design
The Point Scattering Method of simulating radar imagery rigorously models all aspects of the imaging radar phenomena. Its computational algorithms operate on a symbolic representation of the terrain test site to calculate such parameters as range, angle of incidence, resolution cell size, etc. Empirical backscatter data and elevation data are utilized to model the terrain. Additionally, the important geometrical/propagation effects such as shadow, foreshortening, layover, and local angle of incidence are rigorously treated. Applications of radar image simulation to a proposed calibrated SAR system are highlighted: soil moisture detection and vegetation discrimination
Symptoms and Self-Care in Old Age
Self-care has recently come to be recognized as the predominant form of response to illness among the general population, but little is known regarding beliefs and practices of the aged. In this study, beliefs regarding the appropriate response to 53 common symptoms were investigated and contrasted to actual responses. Various forms of self-care were seen as appropriate responses to symptoms ranging from minor to potentially serious. Preference for self-care responses appears to be related to perceived severity of symptoms and the perceived effectiveness of available self-care responses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66474/2/10.1177_073346488600500207.pd
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