4,303 research outputs found
Counting occurrences of some subword patterns
We find generating functions the number of strings (words) containing a
specified number of occurrences of certain types of order-isomorphic classes of
substrings called subword patterns. In particular, we find generating functions
for the number of strings containing a specified number of occurrences of a
given 3-letter subword pattern.Comment: 9 page
Detection system ensures positive alarm activation in digital message loss
Lost Word Detection System /LOWDS/ provides special identification for each error detection message transmitted from receiver to transmitter. The message is identified as an original message or an n-times retransmitted message so the receiver can detect where a retransmission request was not fulfilled and activate an alarm
Line-of-Sight Reddening Predictions: Zero Points, Accuracies, the Interstellar Medium, and the Stellar Populations of Elliptical Galaxies
Revised (B-V)_0-Mg_2 data for 402 elliptical galaxies are given to test
reddening predictions which can also tell us both what the intrinsic errors are
in this relationship among gE galaxy stellar populations, as well as details of
nearby structure in the interstellar medium (ISM) of our Galaxy and of the
intrinsic errors in reddening predictions. Using least-squares fits, the
explicit 1-sigma errors in the Burstein-Heiles (BH) and the Schlegel et al.
(IR) predicted reddenings are calculated, as well as the 1-sigma observational
error in the (B-V)_0-Mg_2 for gE galaxies. It is found that, in directions with
E(B-V)<0.100 mag (where most of these galaxies lie), 1-sigma errors in the IR
reddening predictions are 0.006 to 0.009 in E(B-V) mag, those for BH reddening
prediction are 0.011 mag, and the 1-sigma agreement between the two reddening
predictions is 0.007 mag. IR predictions have an accuracy of 0.010-0.011 mag in
directions with E(B-V)>= 0.100 mag, significantly better than those of the BH
predictions (0.024-0.025). Gas-to-dust variations that vary by a factor of 3,
both high and low, exist along many lines-of-sight in our Galaxy. The approx
0.02 higher reddening zero point in E(B-V) previously determined by Schlegel et
al. is confirmed, primarily at the Galactic poles. Despite this, both methods
also predict many directions with E(B-V)<0.015 mag. Independent evidence of
reddening at the North Galactic pole is reviewed, with the conclusion that
there still exists directions at the NGP that have E(B-V)<<0.01. Two lines of
evidence suggest that IR reddenings are overpredicted in directions with high
gas-to-dust ratios. As high gas-to-dust directions in the ISM also include the
Galactic poles, this overprediction is the likely cause of the E(B-V) = 0.02
mag larger IR reddening zero point.Comment: 5 figure
An optical spectroscopic survey of the 3CR sample of radio galaxies with z<0.3. III. Completing the sample
We present optical nuclear spectra for nine 3CR radio sources obtained with
the Telescopio Nazionale Galileo, that complete our spectroscopic observations
of the sample up to redshifts 0.3. We measure emission line luminosities
and ratios, and derive a spectroscopic classification for these sources.Comment: Accepted for publication in A&A. We provide as additional material
two tables presenting the main data for the whole sample, combining the
results presented here with those of Paper I and Paper I
A catalogue of galaxies behind the southern Milky Way. - II. The Crux and Great Attractor regions (l = 289deg - 338deg)
In this second paper of the catalogue series of galaxies behind the southern
Milky Way, we report on the deep optical galaxy search in the Crux region
(289deg <= l <= 318deg and -10deg <= b <= 10deg) and the Great Attractor region
(316deg <= l <= 338deg and -10deg <= b <= 10deg). The galaxy catalogues are
presented, a brief description of the galaxy search given, as well as a
discussion on the distribution and characteristics of the uncovered galaxies. A
total of 8182 galaxies with major diameters D >= 0.2 arcmin were identified in
this ~850 square degree area: 3759 galaxies in the Crux region and 4423
galaxies in the Great Attractor region. Of the 8182 galaxies, 229 (2.8%) were
catalogued before in the optical (3 in radio) and 251 galaxies have a reliable
(159), or likely (92) cross-identification in the IRAS Point Source Catalogue
(3.1%). A number of prominent overdensities and filaments of galaxies are
identified. They are not correlated with the Galactic foreground extinction and
hence indicative of extragalactic large-scale structures. Redshifts obtained at
the South African Astronomical Observatory (SAAO) for 518 of the newly
catalogued galaxies in the Crux and Great Attractor regions (Fairall et al.
1998; Woudt et al. 1999) confirm distinct voids and clusters in the area here
surveyed. With this optical galaxy search, we have reduced the width of the
optical `Zone of Avoidance' for galaxies with extinction-corrected diameters
larger than 1.3 arcmin from extinction levels A_B >= 1.0 mag to A_B >= 3.0 mag:
the remaining optical Zone of Avoidance is now limited by |b| <= 3deg (see Fig.
16).Comment: 19 pages, 16 figures, accepted for publication in A&A. Tables will
shortly be available in electronic version at the CDS. Full resolution
(colour) copies of Figures 1, 2, 3 and 16 are available at
http://mensa.ast.uct.ac.za/~pwoud
A Task-based Knowledge Management Case for Addressing Merger and Acquisition Risk
For some firms, mergers and acquisitions (M&A) activity is part of a normal growth strategy in a competitive environment. Such firms accumulate a body of M&A knowledge that can be employed for the benefits of organisational continuity. Despite the significant risks associated with M&A failure, they are able to approach each new event with a set of experiential learnings that can better inform their actions. For other firms however, M&A represent rare occasions in the company’s lifecycle. Valuable integration knowledge is inherently fragmented, making these firms especially vulnerable to M&A risks. A case study was undertaken in a firm that matches this latter category. A Task-based Knowledge Management approach provided a framework for inquiry. Our focus was on knowledge work associated with the post-acquisition integration task of an acquirer. The findings reveal substantial M&A learnings, which if harnessed adequately, can enhance firm’s competitive advantage and mitigate against associated M&A risk
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