479 research outputs found
Properties of the redshift
Central to any analysis of dynamical systems, or large scale motion, is the interpretation of redshifts of galaxies as classical Doppler velocity shifts. This is a testable assumption and for many years evidence has accumulated that is inconsistent with the assumption. Here, the authors review recent evidence suggesting systematic radial dependence and temporal variation of redshifts
Dissepimental rugose corals of Upper Pennsylvanian (Missourian) rocks of Kansas
76 p., 8 pl., 11 fig.http://paleo.ku.edu/contributions.htm
Taxonomic and environmental study of two dibunophyllid coral species from Upper Pennsylvanian rocks of Kansas
12 p., 4 fig.http://paleo.ku.edu/contributions.htm
A general maximum entropy principle for self-gravitating perfect fluid
We consider a self-gravitating system consisting of perfect fluid with
spherical symmetry. Using the general expression of entropy density, we
extremize the total entropy under the constraint that the total number of
particles is fixed. We show that extrema of coincides precisely with the
relativistic Tolman-Oppenheimer-Volkoff (TOV) equation of hydrostatic
equilibrium. Furthermore, we apply the maximum entropy principle to a charged
perfect fluid and derive the generalized TOV equation. Our work provides a
strong evidence for the fundamental relationship between general relativity and
ordinary thermodynamics.Comment: 13 pages, no figure. The arguments have been improved so that the
assumption p=p(\rho) is no longer neede
Upper Pennsylvanian Missourian Corals of Iowa
As in Kansas where distinct zonation of corals has been recognized, the dissepimental Rugosa Dibunophyllum, Neokoninckophyllum and Geyerophyllum are invariably associated with limestones and thin calcareous shale interbeds within limestone units. In both states, the nondissepimental rugose genera Lophamplexus and Stereostyllls have been collected from both limestones and thick intervening shale units. The tabulate genera Syringopora and Cladochonus are restricted to limestones in both areas. Although the vertical distribution of Iowa and Kansas dissepimental corals is similar, Iowa rocks contain fewer and generally smaller corals than correlative Kansas units. Elements of the informal dissepimental coral zones 1, 3 and 4 established by Cocke (1970, 1972) in Kansas are presently known in Iowa
New tabulate genus Sutherlandia (Coelenterata, Anthozoa) from Pennsylvanian of Oklahoma and Kansas
8 p., 3 fig.http://paleo.ku.edu/contributions.htm
Liveness-Driven Random Program Generation
Randomly generated programs are popular for testing compilers and program
analysis tools, with hundreds of bugs in real-world C compilers found by random
testing. However, existing random program generators may generate large amounts
of dead code (computations whose result is never used). This leaves relatively
little code to exercise a target compiler's more complex optimizations.
To address this shortcoming, we introduce liveness-driven random program
generation. In this approach the random program is constructed bottom-up,
guided by a simultaneous structural data-flow analysis to ensure that the
generator never generates dead code.
The algorithm is implemented as a plugin for the Frama-C framework. We
evaluate it in comparison to Csmith, the standard random C program generator.
Our tool generates programs that compile to more machine code with a more
complex instruction mix.Comment: Pre-proceedings paper presented at the 27th International Symposium
on Logic-Based Program Synthesis and Transformation (LOPSTR 2017), Namur,
Belgium, 10-12 October 2017 (arXiv:1708.07854
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