143,975 research outputs found
Telespectrograph Patent
Telespectrograph for analyzing upper atmosphere by tracking bodies reentering atmosphere at high velocitie
The Permit Power Revisited: The Theory and Practice of Regulatory Permits in the Administrative State
Two decades ago, Professor Richard Epstein fired a shot at the administrative state that has gone largely unanswered in legal scholarship. His target was the permit power, under which legislatures prohibit a specified activity by statute and delegate to administrative agencies the discretionary power to authorize the activity under terms the agency mandates in a regulatory permit. Accurately describing the permit power as an enormous power in the state, Epstein bemoaned that it had received scant attention in the academic literature. He sought to fill that gap. Centered on the premise that the permit power represents a complete inversion of the proper distribution of power within a legal system, Epstein launched a scathing critique of regulatory permitting in operation, condemning it as a racket for administrative abuses and excesses.
Epstein\u27s assessment of the permit power was and remains accurate in three respects: it is vast in scope, it is ripe for administrative abuse, and it has been largely ignored in legal scholarship. The problem is that, beyond what he got right about the permit power, most of Epstein\u27s critique was based on an incomplete caricature of permitting in theory and practice.
This Article is the first to return comprehensively to the permit power since Epstein\u27s critique, offering a deep account of the theory and practice of regulatory permits in the administrative state. This Article opens by defining the various types of regulatory permits and describing the scope of permitting in the regulatory state. From there it compares different permit design approaches and explores the advantages of general permits, including their ability to mitigate many of the concerns Epstein advanced. This Article then applies a theoretical model to environmental degradation problems and concludes that if certain conditions are met, general permits can effectively respond to many of the complex policy problems of the future. Finally, this Article adds to the scholarship initiated by Epstein by proposing a set of default rules and exceptions for permit design and suggesting how they apply to complex policy problems
Improvement and optimization of a mass spectrometer employing a photoionization source
Ultraviolet filter and monochromator for mass spectrometer employing photoionization sourc
WFIRST Ultra-Precise Astrometry II: Asteroseismology
WFIRST microlensing observations will return high-precision parallaxes,
sigma(pi) < 0.3 microarcsec, for the roughly 1 million stars with H<14 in its
2.8 deg^2 field toward the Galactic bulge. Combined with its 40,000 epochs of
high precision photometry (~0.7 mmag at H_vega=14 and ~0.1 mmag at H=8), this
will yield a wealth of asteroseismic data of giant stars, primarily in the
Galactic bulge but including a substantial fraction of disk stars at all
Galactocentric radii interior to the Sun. For brighter stars, the astrometric
data will yield an external check on the radii derived from the two
asteroseismic parameters, and nu_max, while for the fainter ones, it
will enable a mass measurement from the single measurable asteroseismic
parameter nu_max. Simulations based on Kepler data indicate that WFIRST will be
capable of detecting oscillations in stars from slightly less luminous than the
red clump to the tip of the red giant branch, yielding roughly 1 million
detections.Comment: 13 pages, 6 figures, submitted to JKA
Next Generation M2M Cellular Networks: Challenges and Practical Considerations
In this article, we present the major challenges of future machine-to-machine
(M2M) cellular networks such as spectrum scarcity problem, support for
low-power, low-cost, and numerous number of devices. As being an integral part
of the future Internet-of-Things (IoT), the true vision of M2M communications
cannot be reached with conventional solutions that are typically cost
inefficient. Cognitive radio concept has emerged to significantly tackle the
spectrum under-utilization or scarcity problem. Heterogeneous network model is
another alternative to relax the number of covered users. To this extent, we
present a complete fundamental understanding and engineering knowledge of
cognitive radios, heterogeneous network model, and power and cost challenges in
the context of future M2M cellular networks
Microwave spectroscopy of the Mars atmosphere
A study of the use of millimeter-wavelength spectral transitions to investigate the atmosphere of Mars is presented. In the model experiments investigated it is assumed that a spectrometer in the frequency range from 100 to 260 GHz looks into a modest-sized telescope of from 30 to 50 cm aperture from a near-Mars orbit. The molecules H2O, CO, O2, O3, and H2O2 all have intense spectral lines in the Mars atmosphere in this frequency range and in addition are all very important in understanding the water cycle, the photochemistry, and the circularization in that atmosphere. It is shown that the altitude and the zonal distribution of H2O can be mapped even in atmospheric columns as dry as 0.25 precipital μm. Ozone can be mapped over the entire planet, independent of solar-lighting conditions, dust loading, or clouds in the atmosphere, because millimeter waves are insensitive to any particles that can be suspended in the Mars atmosphere. Because the signal-receiving techniques use superheterodyne devices and narrow spectral lines, zonal and meridional winds can be measured at altitudes above 10 km with a precision approaching approximately 3 m/s by the use of Doppler shifts. Temperature–pressure profiles can be measured to altitudes of 100 km by the use of CO lines in the limb-sounding mode
Magnonic crystal based forced dominant wavenumber selection in a spin-wave active ring
Spontaneous excitation of the dominant mode in a spin-wave active ring -- a
self-exciting positive-feedback system incorporating a spin-wave transmission
structure -- occurs at a certain threshold value of external gain. In general,
the wavenumber of the dominant mode is extremely sensitive to the properties
and environment of the spin-wave transmission medium, and is almost impossible
to predict. In this letter, we report on a backward volume magnetostatic
spin-wave active ring system incorporating a magnonic crystal. When mode
enhancement conditions -- readily predicted by a theoretical model -- are
satisfied, the ring geometry permits highly robust and consistent forced
dominant wavenumber selection.Comment: 4 pages, 3 figure
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