Lateral displacement system for separated rocket stages Patent

Development of remotely controlled shaped charge for lateral displacement of rocket stages after separatio

The baryon mass function for galaxy clusters

Context: The evolution of the cluster abundance with redshift is known to be a powerful cosmological constraint when applied to X-ray clusters. Recently, the evolution of the baryon mass function has been proposed as a new variant that is free of the uncertainties present in the temperature-mass relation. A flat model with Omega_matter ~ 0.3 was shown to be preferred in the case of a standard cold dark matter scenario. Aims: We compared the high redshift predictions of the baryon mass in clusters with data for a more general class of spectra with a varying shape factor Gamma without any restriction to the standard cold dark matter scenario in models normalized to reproduce the local baryon mass function. Methods: Using various halo mass functions existing in the literature we evaluated the corresponding baryon mass functions for the case of the non-standard power spectra mentioned previously. Results: We found that models with Omega_matter ~ 1 and Gamma ~ 0.12 reproduce high redshift cluster data just as well as the concordance model does. Conclusions: Finally, we conclude that the baryon mass function evolution alone does not efficiently discriminate between the more general family of flat cosmological models with non-standard power spectra.Comment: Typos corrected. Replaced to match published version. 5 pages, 2 figures, aa.cl

A flight investigation of the ultra-deep-stall descent and spin recovery characteristics of a 1/6 scale radiocontrolled model of the Piper PA38 Tomahawk

Ultradeep stall descent and spin recovery characteristics of a 1/6 scale radio controlled model of the Piper PA38 Tomahawk aircraft was investigated. It was shown that the full scale PA38 is a suitable aircraft for conducting ultradeep stall research. Spin recovery was accomplished satisfactorily by entry to the ultradeep stall mode, followed by the exit from the ultradeep stall mode. It is concluded that since the PA38 has excellent spin recovery characteristics using normal recovery techniques (opposite rudder and forward control colum pressure), recovery using ultradeep stall would be beneficial only if the pilot suffered from disorientation

Development and characterization analysis of a radar polarimeter

The interaction of electromagnetic waves with natural earth surface was of interest for many years. A particular area of interest in controlled remote sensing experiments is the phenomena of depolarization. The development stages of the radar system are documented. Also included are the laboratory procedures which provides some information about the specifications of the system. The radar system developed is termed the Radar Polarimeter System. A better insight of the operation of the RPS in terms of the newly developed technique--synthetic aperture radar system is provided. System performance in tems of radar cross section, in terms of power, and in terms of signal to noise ratio are also provided. In summary, an overview of the RPS in terms of its operation and design as well as how it will perform in the field is provided

Thermodynamic versus Topological Phase Transitions: Cusp in the Kert\'esz Line

We present a study of phase transitions of the Curie--Weiss Potts model at (inverse) temperature $\beta$, in presence of an external field $h$. Both thermodynamic and topological aspects of these transitions are considered. For the first aspect we complement previous results and give an explicit equation of the thermodynamic transition line in the $\beta$--$h$ plane as well as the magnitude of the jump of the magnetization (for $q \geqslant 3)$. The signature of the latter aspect is characterized here by the presence or not of a giant component in the clusters of a Fortuin--Kasteleyn type representation of the model. We give the equation of the Kert\'esz line separating (in the $\beta$--$h$ plane) the two behaviours. As a result, we get that this line exhibits, as soon as $q \geqslant 3$, a very interesting cusp where it separates from the thermodynamic transition line

The Influence of the Motivational Probe Technique on the Linguistic Domain of the Detroit Tests of Learning Aptitude-2 Testing LD and EMR Students

The purpose of this study was to investigate the influence of the motivational probe technique on the posttest scores of learning disabled and educable mentally retarded students using the Word Opposites and Conceptual Matching subtests taken from the DTLA-2. The effect of individual testing was evaluated by a pre-probe and post-probe scoring of results. A dependent t test was used to test the hypotheses presented in this study. The findings of this study indicated that the motivational probe technique enabled both EMR and LD groups to score significantly higher on each of the four tests

The Hagedorn Temperature and Partition Thermodynamics

We review the resonance gas formalism of hadron thermodynamics and recall that an exponential increase of the resonance spectrum leads to a limiting temperature of hadronic matter. We then show that the number p(n) of ordered partitions of an integer n grows exponentially with n and satisfies the integer counterpart of the statistical bootstrap equation. Considering the set of all partitions as a Gibbs ensemble provides a partition thermodynamics which is also governed by a limiting temperature, determined by the combinatorial structure of the problem. Further associating intrinsic quantum numbers to integers results in a phase diagram equivalent to that found in QCD for hadronic matter as function of temperature and baryochemical potential.Comment: Dedicated to Rolf Hagedorn, 1919-2003. 11 pages, 3 figures. Final version accepted for publication in the European Physical Journal