13,752 research outputs found
A preliminary quarantine analysis of a possible Mariner Venus 1972 mission
Spacecraft contamination preliminary quarantine analysis for possible 1972 Mariner Venus prob
Juncture stress fields in multicellular shell structures. Volume IV - Stresses and deformations of fixed-edge segmental spherical shells Final report
Equations for thin elastic spherical shells and digital program for analysis of stresses and deformation of fixed edge segmental spherical shells - solution by finite difference techniqu
Juncture stress fields in multicellular shell structures. Volume III - Stresses and deformations on fixed-edge segmental conical shells Final report
Equations for thin elastic conical shells and digital program for analysis of stress and deformation on fixed edge segmental conical shells - solution by finite difference techniqu
Manual of Criminal Law and Procedure
Intended to aid to Alaska law enforcement officers in the performance of their duties in the field, this manual was designed to provide brief, quick access to major points of substantive and procedural criminal law. The manual contained discussion and procedural guidelines for investigatory stops, identification procedures including line-ups, arrest, search and seizure, interrogation, as well as discussion of justification for the use of nondeadly and deadly force whether by peace officers or civilians, culpability, entrapment, trial preparation, and media relations. The section on substantive criminal law deals with a selection of crimes most likely to be encountered by "street" officers as defined with the recently enacted Revised Alaska Criminal Code (effective January 1, 1980), desribing elements of each crime, investigative hints, and differences with previous provisions of the criminal code, where relevant.Alaska Department of Law
Grant No. 78-A-014Introduction / Criminal Procedures / Substantive Criminal Law / Justification / Culpability / Entrapment / Trial Preparation / Media Relations / Appendice
‘‘There’s so much more to it than what I initially thought’’: Stepping into researchers’ shoes with a class activity in a first year psychology survey course
In psychology, it is widely agreed that research methods, although central to the discipline, are particularly challenging to learn and teach, particularly at introductory level. This pilot study explored the potential of embedding a student-conducted research activity in a one-semester undergraduate Introduction to Psychology survey course, with the aims of (a) engaging students with the topic of research methods; (b) developing students’ comprehension and application of research methods concepts; and (c) building students’ ability to link research with theory. The research activity explored shoe ownership, examining gender differences and relationships with age, and linking to theories of gender difference and of consumer identity. The process of carrying out the research and reflecting on it created a contextualized, active learning environment in which students themselves raised many issues that research methods lectures seek to cover. Students also wrote richer assignments than standard first year mid-term essay
Investigation of juncture stress fields in multicellular shell structures
Discontinuity stress fields in thin elastic multicellular shell structures subject to inertial, pressure, and thermal loadin
Determination of ocean transports and velocities by electromagnetic effects
The electric potentials in and about an ocean current are shown to be related in a simple fashion to the total fluid transport. In many waters, surface measurements alone permit the determination of this total transport. It is also established that the local vertical potential gradient is a measure of the local velocity. Several techniques of measurement, including the Geomagnetic electrokinetograph method, and the errors which may be involved in each, are discussed
Decoherence induced by Smith-Purcell radiation
The interaction between charged particles and the vacuum fluctuations of the
electromagnetic field induces decoherence, and therefore affects the contrast
of fringes in an interference experiment. In this article we show that if a
double slit experiment is performed near a conducting grating, the fringe
visibility is reduced. We find that the reduction of contrast is proportional
to the number of grooves in the conducting surface, and that for realistic
values of the parameters it could be large enough to be observed. The effect
can be understood in terms of the Smith-Purcell radiation produced by the
surface currents induced in the conductor.Comment: 10 pages, 3 figures. Improved discussion on experimental
perspectives. References added. Version to appear in Phys. Rev.
IC 751: a new changing-look AGN discovered by NuSTAR
We present the results of five NuSTAR observations of the type 2 active
galactic nucleus (AGN) in IC 751, three of which were performed simultaneously
with XMM-Newton or Swift/XRT. We find that the nuclear X-ray source underwent a
clear transition from a Compton-thick () to a Compton-thin () state on timescales of months, which makes
IC 751 the first changing-look AGN discovered by NuSTAR. Changes of the
line-of-sight column density at a level are also found on a
time-scale of hours ().
From the lack of spectral variability on timescales of ks we infer
that the varying absorber is located beyond the emission-weighted average
radius of the broad-line region, and could therefore be related either to the
external part of the broad-line region or a clumpy molecular torus. By adopting
a physical torus X-ray spectral model, we are able to disentangle the column
density of the non-varying absorber () from that of the varying clouds
[], and to constrain that of
the material responsible for the reprocessed X-ray radiation (). We find evidence of significant intrinsic X-ray
variability, with the flux varying by a factor of five on timescales of a few
months in the 2-10 and 10-50 keV band.Comment: Accepted for publication in ApJ, 11 pages, 6 figure
Superlong GRBs
We searched for anomalously long GRBs (GRBs) in the archival records of the
Burst and Transient Sources Experiment (BATSE). Ten obvious superlong (>500 s)
GRBs with almost continuous emission episodes were found. Nine of these events
are known from the BATSE catalog, but five have no duration estimates; we found
one burst for the first time. We also detected events with emission episodes
separated by a long period of silence (up to 1000 s) with a total duration of
1000--2000 s. In the latter case, we cannot reach an unequivocal conclusion
about a common origin of the episodes due to the BATSE poor angular resolution.
However, for most of these pairs, the probability of a coincidence of
independent GRBs is much lower than unity, and the probability that all of
these are coincidences is 10E-8. All of the events have a hardness ratio (the
ratio of the count rates in different energy channels) typical of GRBs, and
their unique duration is unlikely to be related to their high redshifts.
Superlong bursts do not differ in their properties from typical long (>2 s)
GRBs. We estimated the fraction of superlong GRBs (>500 s) among the long GRBs
in the BATSE sample with fluxes up to 0.1 ph cm^{-2} s^{-1} to be between 0.3
and 0.5%, which is higher than the estimate based on the BATSE catalog.Comment: 11 pages, 4 figures, 3 tables, translation is made by Astronomy
Letter
- …