1,670 research outputs found
Total Solar Eclipse, January 24, 1925
On January 24, 1925, a total eclipse of the sun was visible throughout much of New England. This account, written by Halsey DeWolf, describes the eclipse as viewed from Watch Hill, Rhode Island
Least Generalizations and Greatest Specializations of Sets of Clauses
The main operations in Inductive Logic Programming (ILP) are generalization
and specialization, which only make sense in a generality order. In ILP, the
three most important generality orders are subsumption, implication and
implication relative to background knowledge. The two languages used most often
are languages of clauses and languages of only Horn clauses. This gives a total
of six different ordered languages. In this paper, we give a systematic
treatment of the existence or non-existence of least generalizations and
greatest specializations of finite sets of clauses in each of these six ordered
sets. We survey results already obtained by others and also contribute some
answers of our own. Our main new results are, firstly, the existence of a
computable least generalization under implication of every finite set of
clauses containing at least one non-tautologous function-free clause (among
other, not necessarily function-free clauses). Secondly, we show that such a
least generalization need not exist under relative implication, not even if
both the set that is to be generalized and the background knowledge are
function-free. Thirdly, we give a complete discussion of existence and
non-existence of greatest specializations in each of the six ordered languages.Comment: See http://www.jair.org/ for any accompanying file
Investigation of line-of-sight propagation in dense atmosphere, phase 3, part 1
The investigation of microwave absorption in the 1 to 10 GHz frequency band by the Jovian atmosphere has continued, and an estimate of the strength of signal fading at these frequencies due to layers of turbulence in Jupiter's atmosphere is given. The microwave absorption due to gaseous ammonia is estimated both in terms of a power loss in dB/km, and in total power loss in dB for slant-path communication with a probe at altitudes down to pressures of several tens of atmospheres. The graphs indicate a frequency-squared scaling of the absorption, and appreciable losses at altitudes where the pressure is several atmospheres. An estimate of turbulence strength is given. This may turn out to be quite crude considering the absence of any relevant data. A planetary scaling law which appears to hold reasonably well for Earth to Venus, is extrapolated to Jupiter. No reasonable modifications of the estimate can alter the conclusion that direct-path fading is negligible for pressure regimes up to 20 atm
Cumulants of QCD Multiplicity Distributions in Small Phase Space Bins
It is shown that, as functions of their rank, cumulants of QCD multiplicity
distributions in small phase space bins possess the quasi- oscillating behavior
similar to that found for them in the total rapidity range. First minimum moves
to lower ranks for smaller bins. For the total rapidity range, it moves to
higher ranks with energy increase. The running property of the QCD coupling
constant is in charge of these effects which can be verified in experiment.Comment: 7 pages, no Figs, preprint IP-ASTP-19; FIAN-TD 94/
Table F-2. Datapoint Species Data, Penobscot County, Maine, 2004-2008
https://digitalmaine.com/elliotsville_plantation_inc_docs/1003/thumbnail.jp
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