14,496 research outputs found
Problems associated with operations and measurement in cryogenic wind tunnels
Cryogenic wind tunnel T'3 under continuous blower operation has been the object of improvements and the installation of auxiliary equipment, dealing in particular with the enlargement of the liquid nitrogen injection reservoir and the hook-up to a fast data acquisition system. Following a brief description of the installation and its functioning, we present the main experimental techniques and the instrumentation used in the cryogenic environment
A Way Out of the Quantum Trap
We review Event Enhanced Quantum Theory (EEQT). In Section 1 we address the
question "Is Quantum Theory the Last Word". In particular we respond to some of
recent challenging staments of H.P. Stapp. We also discuss a possible future of
the quantum paradigm - see also Section 5. In Section 2 we give a short sketch
of EEQT. Examples are given in Section 3. Section 3.3 discusses a completely
new phenomenon - chaos and fractal-like phenomena caused by a simultaneous
"measurement" of several non-commuting observables (we include picture of
Barnsley's IFS on unit sphere of a Hilbert space). In Section 4 we answer
"Frequently Asked Questions" concerning EEQT.Comment: Replacement. Corrected affiliation. Latex, one .jpg figure. To appear
in Proc. Conf. Relativistic Quantum Measurements, Napoli 1998, Ed. F.
Petruccion
An Approximation to the Likelihood Function for Band-Power Estimates of CMB Anisotropies
Band-power estimates of cosmic microwave background fluctuations are now
routinely used to place constraints on cosmological parameters. For this to be
done in a rigorous fashion, the full likelihood function of band-power
estimates must be employed. Even for Gaussian theories, this likelihood
function is not itself Gaussian, for the simple reason that band-powers measure
the {\em variance} of the random sky fluctuations. In the context of Gaussian
sky fluctuations, we use an ideal situation to motivate a general form for the
full likelihood function from a given experiment. This form contains only two
free parameters, which can be determined if the 68% and 95% confidence
intervals of the true likelihood function are known. The ansatz works
remarkably well when compared to the complete likelihood function for a number
of experiments. For application of this kind of approach, we suggest that in
the future both 68% and 95% (and perhaps also the 99.7%) confidence intervals
be given when reporting experimental results.Comment: Published versio
A New Local Temperature Distribution Function for X-ray Clusters: Cosmological Applications
(abridged) We present a new determination of the local temperature function
of X-ray clusters. We use a new sample comprising fifty clusters for which
temperature information is now available, making it the largest complete sample
of its kind. It is therefore expected to significantly improve the estimation
of the temperature distribution function of moderately hot clusters. We find
that the resulting temperature function is higher than previous estimations,
but agrees well with the temperature distribution function inferred from the
BCS and RASS luminosity function. We have used this sample to constrain the
amplitude of the matter fluctuations on cluster's scale of
Mpc, assuming a mass-temperature relation based
on recent numerical simulations. We find for an
model. Our sample provides an ideal reference at to
use in the application of the cosmological test based on the evolution of X-ray
cluster abundance (Oukbir & Blanchard 1992, 1997). Using Henry's sample, we
find that the abundance of clusters at is significantly smaller, by
a factor larger than 2, which shows that the EMSS sample provides strong
evidence for evolution of the cluster abundance. A likelihood analysis leads to
a rather high value of the mean density parameter of the universe: (open case) and (flat case), which is
consistent with a previous, independent estimation based on the full EMSS
sample by Sadat et al.(1998). Some systematic uncertainties which could alter
this result are briefly discussed.Comment: 31 pages, 12 figures, mathches the version published in Astronomy and
Astrophysic
Tests with three-dimensional adjustments in the rectangular working section of the French T2 wind tunnel with an AS 07-type swept-back wing model
The results obtained on the AS 07 wing and the working section walls for three types of configurations are reported. The first, called non-adapted, corresponds to the divergent upper and lower rectilinear walls which compensate for limit layer thickening. It can serve as a basis for complete flow calculations. The second configuration corresponds to wall shapes determined from calculations which tend to minimize interference at the level of the fuselage. Finally, the third configuration, called two-dimensional adaptation, uses the standard method for T2 profile tests. This case was tested to determine the influence of wall shape and error magnitude. These results are not sufficient to validate the three-dimensional adaptation; they must be coordinated with calculations or with unlimited atmosphere tests
Sex differences between primary and secondary psychopathy, parental bonding, and attachment style.
Sex differences in primary and secondary psychopathic traits and behaviors are consistently evidenced, although less is known about the developmental trajectories of these differences and why they might arise. In this study (N = 362) we investigated whether men and women reporting higher levels of primary or secondary psychopathic traits differed in retrospective accounts of how cold and controlling both their mother and father were during childhood, and how anxious and avoidant they are about contemporary relationships. Primary psychopathic traits in men related to controlling mothers and avoidant attachment, whereas in women they related to uncaring fathers and both anxious and avoidant attachment. Secondary psychopathic traits in men were predicted by uncaring mothers and fathers, as well as anxious attachment, whereas in women, neither parental bonding nor attachment style were related. Results are discussed from an evolutionary, life history theory paradigm
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