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The European Television Sports Rights Market: Balancing Culture and Commerce
On the M\"obius Function and Topology of General Pattern Posets
We introduce a formal definition of a pattern poset which encompasses several
previously studied posets in the literature. Using this definition we present
some general results on the M\"obius function and topology of such pattern
posets. We prove our results using a poset fibration based on the embeddings of
the poset, where embeddings are representations of occurrences. We show that
the M\"obius function of these posets is intrinsically linked to the number of
embeddings, and in particular to so called normal embeddings. We present
results on when topological properties such as Cohen-Macaulayness and
shellability are preserved by this fibration. Furthermore, we apply these
results to some pattern posets and derive alternative proofs of existing
results, such as Bj\"orner's results on subword order.Comment: 28 Page
The economics of defence in France and the UK
France and the UK face similar geostrategic circumstances: both were once Great Powers and still retain their positions among the five permanent members of the UN Security Council. During the Cold War both were dwarfed by the super-powers and were thus extremely sensitive about their status: what the French called their grandeur and the British called their seat at the top table. Despite their strategic similarities, they have differed in many of their defence policy choices and in particular how they balanced their strategic aspirations with their limited financial resources. Thus a comparison of British and French defence policies provides a revealing case study of military choices
A Hubble Space Telescope Survey of X-ray Luminous Galaxy Clusters: Gravitationally Lensed Arcs and EROs
We are conducting a systematic lensing survey of X-ray luminous galaxy
clusters at z~0.2 using the Hubble Space Telescope and large ground-based
telescopes. We summarize initial results from our survey, including a
measurement of the inner slope of the mass profile of A383, and a search for
gravitationally lensed Extremely Red Objects.Comment: 4 pages, 2 figures. To appear in "A New Era in Cosmology" (ASP
Conference Proceedings), eds. T. Shanks and N. Metcalf
On the M\"obius Function of Permutations With One Descent
The set of all permutations, ordered by pattern containment, is a poset. We
give a formula for the M\"obius function of intervals in this poset,
for any permutation with at most one descent. We compute the M\"obius
function as a function of the number and positions of pairs of consecutive
letters in that are consecutive in value. As a result of this we show
that the M\"obius function is unbounded on the poset of all permutations. We
show that the M\"obius function is zero on any interval where
has a triple of consecutive letters whose values are consecutive and monotone.
We also conjecture values of the M\"obius function on some other intervals of
permutations with at most one descent
Monitor assures availability and quality of communication channels
System monitors a communication channel for proper circuit parameters and energizes an alarm if these parameters do not fall within allowable limits. It comprises a monitor-signal transmitter at the transmitting end of the channel and a monitor-signal receiver at the receiving end
Intervals of Permutations with a Fixed Number of Descents are Shellable
The set of all permutations, ordered by pattern containment, is a poset. We
present an order isomorphism from the poset of permutations with a fixed number
of descents to a certain poset of words with subword order. We use this
bijection to show that intervals of permutations with a fixed number of
descents are shellable, and we present a formula for the M\"obius function of
these intervals. We present an alternative proof for a result on the M\"obius
function of intervals such that has exactly one descent. We
prove that if has exactly one descent and avoids 456123 and 356124, then
the intervals have no nontrivial disconnected subintervals; we
conjecture that these intervals are shellable
Computer program for fitting low-order polynomial splines by method of least squares
FITLOS is computer program which implements new curve fitting technique. Main program reads input data, calls appropriate subroutines for curve fitting, calculates statistical analysis, and writes output data. Method was devised as result of need to suppress noise in calibration of multiplier phototube capacitors
Hubble, chandra and keck constraints on massive galaxy clusters at z=0.2 and z=0.5
I present recent observations from two Hubble Space Telescope(HST)/ACS programs
that target the most X–ray luminous and thus (presumably) most massive galaxy clusters at
z=0.5 – the highest redshift at which complete, well–defined samples of such rare systems
are available. The first program (GO:9836, PI: R.S. Ellis) exploits a huge mosaic of 41 ACS
pointings spanning a 10 Mpc region centered on MS0451-03. This is the largest contiguous
space–based image of a cluster to date. I describe a preliminary weak–lensing analysis and a new
Keck/DEIMOS redshift catalog of 1000 galaxies in this field. The second program (GO:9722,
PI: H. Ebeling) studies the core regions of the twelve most luminous clusters at z≥0.5 from
the MAssive Cluster Survey (MACS; Ebeling et al. 2001). Multi–color ACS observations in
combination with recent Keck/LRIS spectroscopy of gravitational arcs constrain the distribution
of mass in the cluster cores, thus laying the foundation for detailed multi–diagnostic (lensing,
X–ray, near–infrared, SZE) investigation of this sample. For example, it is of particular interest
to explore how the structure and state of relaxation of massive clusters evolved between this
sample at z≥0.5 that measured by Smith et al. (2004, astro–ph/0403588) at z=0.2
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