18,367 research outputs found
Fuzzy Recommendations in Marketing Campaigns
The population in Sweden is growing rapidly due to immigration. In this
light, the issue of infrastructure upgrades to provide telecommunication
services is of importance. New antennas can be installed at hot spots of user
demand, which will require an investment, and/or the clientele expansion can be
carried out in a planned manner to promote the exploitation of the
infrastructure in the less loaded geographical zones. In this paper, we explore
the second alternative. Informally speaking, the term Infrastructure-Stressing
describes a user who stays in the zones of high demand, which are prone to
produce service failures, if further loaded. We have studied the
Infrastructure-Stressing population in the light of their correlation with
geo-demographic segments. This is motivated by the fact that specific
geo-demographic segments can be targeted via marketing campaigns. Fuzzy logic
is applied to create an interface between big data, numeric methods for
processing big data and a manager.Comment: conferenc
Research in the general area of non-linear dynamical systems Final report, 8 Jun. 1965 - 8 Jun. 1967
Nonlinear dynamical systems research on systems stability, invariance principles, Liapunov functions, and Volterra and functional integral equation
Lateralization of circadian pacemaker output: Activation of left- and right-sided luteinizing hormone-releasing hormone neurons involves a neural rather than a humoral pathway
Locomotor activity and luteinizing hormone (LH) secretion in golden hamsters share a common circadian pacemaker in the suprachiasmatic nucleus (SCN), but the rhythms do not seem to share a common output pathway from the SCN. Locomotion is believed to be driven by humoral factor(s), whereas LH secretion may depend on specific ipsilateral neural efferents from the SCN to LH releasing hormone (LHRH)-containing neurons in the preoptic area. In this paper we provide the first functional evidence for such efferents in neurologically intact hamsters by exploiting a phenomenon known as splitting in constant light, in which circa-12 hr (approximately 12 hr) locomotor activity bouts reflect an antiphase oscillation of the left and right sides of the bilaterally paired SCN. In ovariectomized, estrogen-treated (OVX + E2) female hamsters, splitting is also known to include circa-12 hr LH secretory surges. Here we show that behaviorally split OVX + E2 females exhibit a marked left-right asymmetry in immunoreactive c-Fos expression in both SCN and activated LHRH neurons, with the percentage of LHRH+/c-Fos+ double-labeled cells approximately fivefold higher on the side corresponding to the side of the SCN with higher c-Fos immunoreactivity. Our results suggest that splitting involves alternating left- and right-sided stimulation of LHRH neurons; under such circumstances, the functional activity of the neuroendocrine hypothalamus mirrors intrinsic side-to-side differences in SCN gene expression. The circadian regulation of reproductive activity depends on lateralized, point-to-point axonal projections rather than on diffusible factors
The ``Outside-In'' Outburst of HT Cassiopeiae
We present results from photometric observations of the dwarf nova system HT
Cas during the eruption of November 1995. The data include the first
two--colour observations of an eclipse on the rise to outburst. They show that
during the rise to outburst the disc deviates significantly from steady state
models, but the inclusion of an inner-disc truncation radius of about 4
and a ``flared'' disc of semi-opening angle of produces
acceptable fits. The disc is found to have expanded at the start of the
outburst to about , as compared to quiescent measurements. The
accretion disc then gradually decreases in radius reaching during
the last stages of the eruption. Quiescent eclipses were also observed prior to
and after the eruption and a revised ephemeris is calculated.Comment: 9 pages, 11 figures, to appear in MNRA
Chandra observations of Cygnus OB2
Cygnus OB2 is the nearest example of a massive star forming region,
containing over 50 O-type stars and hundreds of B-type stars. We have analyzed
two Chandra pointings in Cyg OB2, detecting ~1700 X-ray sources, of which ~1450
are thought to be members of the association. Optical and near-IR photometry
has been obtained for ~90% of these sources from recent deep Galactic plane
surveys. We have performed isochrone fits to the near-IR color-magnitude
diagram, deriving ages of 3.5(+0.75,-1.0) and 5.25(+1.5,-1.0) Myrs for sources
in the two fields, both with considerable spreads around the pre-MS isochrones.
The presence of a second population in the region, somewhat older than the
present-day O-type stars, has been suggested by other authors and fits with the
ages derived here. The fraction of sources with inner circumstellar disks (as
traced by the K-band excess) is found to be very low, but appropriate for a
population of age ~5 Myrs. We measure the stellar mass functions and find a
power-law slope of Gamma = -1.09 +/- 0.13, in good agreement with the global
mean value estimated by Kroupa. A steepening of the mass function at high
masses is observed and we suggest this is due to the presence of the previous
generation of stars that have lost their most massive members. Finally,
combining our mass function and an estimate of the radial density profile of
the association suggests a total mass of Cyg OB2 of ~30,000 Msun, similar to
that of many of our Galaxy's most massive star forming regions.Comment: 6 pages, 4 figures, conference proceedings for JENAM 2010: Star
Clusters in the Era of Large Surveys, Editors: A.Moitinho and J. Alve
Using a complete spectroscopic survey to find red quasars and test the KX method
We present an investigation of quasar colour-redshift parameter space in
order to search for radio-quiet red quasars and to test the ability of a
variant of the KX quasar selection method to detect quasars over a full range
of colour without bias. This is achieved by combining IRIS2 imaging with the
complete Fornax Cluster Spectroscopic Survey to probe parameter space
unavailable to other surveys. We construct a new sample of 69 quasars with
measured bJ - K colours. We show that the colour distribution of these quasars
is significantly different from that of the Large Bright Quasar Survey's
quasars at a 99.9% confidence level. We find 11 of our sample of 69 quasars
have signifcantly red colours (bJ - K >= 3.5) and from this, we estimate the
red quasar fraction of the K <= 18.4 quasar population to be 31%, and robustly
constrain it to be at least 22%. We show that the KX method variant used here
is more effective than the UVX selection method, and has less colour bias than
optical colour-colour selection methods.Comment: 11 pages, 14 figures, accepted for publication in MNRA
A âmovement for improvementâ?: a qualitative study of the adoption of social movement strategies in the implementation of a quality improvement campaign
Given the difficulties of implementing âtop-downâ quality improvements, health service leaders have turned to methods that empower clinicians to co-produce âbottom-upâ improvements. This has involved the adoption of strategies and activities associated with social movements, with clinicians encouraged to participate in collective action towards the shared goal of improvement. This paper examines the adoption of social movement methods by hospital managers as a strategy for implementing a quality improvement âcampaignâ. Our case study suggests that, despite the claim of empowering clinicians to develop âbottom-upâ improvements, the use of social movement methods is narrowly concerned with engaging clinicians in a pre-determined programme of âtop-downâ change. It finds a prominent role for âhybridâ clinical leaders and other staff representatives in the mobilisation of the campaign, especially for enrolling clinicians in change activities. The work of these âhybridsâ suggests some degree of creative mediation between clinical and managerial interests, but more often alignment with the aspirations of management. The study raises questions about the translation of social movements theories as a strategy for managing change and re-inventing professionalism
Experimental determination of the complete spin structure for anti-proton + proton -> anti-\Lambda + \Lambda at anti-proton beam momentum of 1.637 GeV/c
The reaction anti-proton + proton -> anti-\Lambda + \Lambda -> anti-proton +
\pi^+ + proton + \pi^- has been measured with high statistics at anti-proton
beam momentum of 1.637 GeV/c. The use of a transversely-polarized frozen-spin
target combined with the self-analyzing property of \Lambda/anti-\Lambda decay
allows access to unprecedented information on the spin structure of the
interaction. The most general spin-scattering matrix can be written in terms of
eleven real parameters for each bin of scattering angle, each of these
parameters is determined with reasonable precision. From these results all
conceivable spin-correlations are determined with inherent self-consistency.
Good agreement is found with the few previously existing measurements of spin
observables in anti-proton + proton -> anti-\Lambda + \Lambda near this energy.
Existing theoretical models do not give good predictions for those
spin-observables that had not been previously measured.Comment: To be published in Phys. Rev. C. Tables of results (i.e. Ref. 24) are
available at http://www-meg.phys.cmu.edu/~bquinn/ps185_pub/results.tab 24
pages, 16 figure
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