Inertial reference unit

Unit provides rate damping, linear velocity changes and angular position information to attitude control system during turns and motor burns

Relativistic precession of quantum elliptical states in the Coulomb potential

A special relativistic perturbation to non-relativistic quantum mechanics is shown to lead to the special relativistic prediction for the rate of precession for quantum states in the Coulomb potential. This behavior is shown using SO(4) coherent states as examples. These states are localized on Kepler ellipses and precess in the presence of a relativistic perturbation.Comment: 10 pages, 3 figures, submitted to Am.J.Phys, revised for style, improved figure

Individual and Society: Sociological Social Psychology

Unlike the few other texts for undergraduate sociological social psychology courses that present 3 distinct traditions (or faces ) ... Symbolic Interactionist (SI), Social Structure and Personality (SSP), and Group Processes and Structure (GPS) by topic alone, this text initially discusses these faces by research tradition, and emphasizes the different theoretical frameworks within which social psychological analyses are conducted. With this approach, the authors make clear the link between face of sociological social psychology, theory, and methodology. And students gain an appreciably better understanding of the field of sociological social psychology; how and why social psychologists trained in sociology ask particular kinds of questions; the types of research they are involved in; and how their findings have been, or can be, applied to contemporary societal patterns and problems. Great writing makes this approach successful and interesting for students, resulting in a richer, more powerful course experience. A website offers instructors high quality support material, written by the authors, which you will appreciate and value -- Provided by publisher

Lagrangian acceleration statistics in turbulent flows

We show that the probability densities af accelerations of Lagrangian test particles in turbulent flows as measured by Bodenschatz et al. [Nature 409, 1017 (2001)] are in excellent agreement with the predictions of a stochastic model introduced in [C. Beck, PRL 87, 180601 (2001)] if the fluctuating friction parameter is assumed to be log-normally distributed. In a generalized statistical mechanics setting, this corresponds to a superstatistics of log-normal type. We analytically evaluate all hyperflatnes factors for this model and obtain a flatness prediction in good agreement with the experimental data. There is also good agreement with DNS data of Gotoh et al. We relate the model to a generalized Sawford model with fluctuating parameters, and discuss a possible universality of the small-scale statistics.Comment: 10 pages, 2 figure

MRI and clinical resolution of a suspected intracranial toxoplasma granuloma with medical treatment in a domestic short hair cat

A two-year-old cat was presented with a left paradoxical vestibular syndrome. MRI of the brain revealed an extra-axial homogenously contrast enhancing mass in the region of the left caudal cerebellar peduncle. Toxoplasma serology was consistent with active infection and the lesion was suspected to be a toxoplasma granuloma. Following eight weeks of tapering oral prednisolone and 11 weeks of oral clindamycin treatment, repeat MRI revealed resolution of the lesion. Eighteen months after initial diagnosis, the cat remained neurologically normal. Differential diagnoses for a solitary, extra-axial, contrast enhancing mass lesion in the feline brain should include toxoplasma granuloma, which can undergo MRI and clinical resolution with medical treatment

Dispelling the myth of robotic efficiency: why human space exploration will tell us more about the Solar System than will robotic exploration alone

There is a widely held view in the astronomical community that unmanned robotic space vehicles are, and will always be, more efficient explorers of planetary surfaces than astronauts (e.g. Coates, 2001; Clements 2009; Rees 2011). Partly this is due to a common assumption that robotic exploration is cheaper than human exploration (although, as we shall see, this isn't necessarily true if like is compared with like), and partly from the expectation that continued developments in technology will relentlessly increase the capability, and reduce the size and cost, of robotic missions to the point that human exploration will not be able to compete. I will argue below that the experience of human exploration during the Apollo missions, more recent field analogue studies, and trends in robotic space exploration actually all point to exactly the opposite conclusion.Comment: 12 pages; 5 figures. Published, with minor modifications, in Astronomy and Geophysics, Vol. 53, pp. 2.22-2.26, 201

Influence of bulk turbulence and entrance boundary layer thickness on the curved duct flow field

The objective of this investigation was the experimental evaluation of bulk turbulence and boundary thickness influence on the secondary flow development in a square, 90 deg turning duct. A three dimensional laser velocimetry system was utilized to measure the mean and fluctuating components of velocity in the large curved duct facility. The three dimensional development of the viscous shear layers in the curved duct has a strong influence on the complete flow field. Since ducted three dimensional flows are found in many engineering applications, including gas turbine engines, and contain high turbulence levels and high wall heat transfer rates, they present a difficult challenge to computational fluid mechanics codes. Turbulence modeling remains one of constraints to CFD advance due to inadequate physical understanding and experimental definition of turbulent shear flows. The results of this investigation expand the curved duct data base to higher turbulence levels and thicker entrance boundary layers. The experimental results provide a challenging benchmark data base for computational fluid dynamics code development and validation. The variation of inlet bulk turbulence intensity provides additional information to aid in turbulence model evaluation