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Yet another sample of RFGC galaxies  [PDF]
S. L. Parnovsky,A. S. Parnowski
Physics , 2012, DOI: 10.1007/s10509-012-1267-3
Abstract: We present a new version of a sample of galaxies from the Revised Flat Galaxy Catalogue (RFGC), which have redshift and HI line width data. We also give the parameters of the collective motion model determined upon this sample. The considered models of motion include the dipole (bulk flow), the quadrupole (cosmic shear) and the octupole components. We also considered higher-order multipoles. In all cases the obtained parameters matched the {\Lambda}CDM cosmology.
Yet another zeta function and learning  [PDF]
Igor Rivin
Mathematics , 2001,
Abstract: We study the convergence speed of the batch learning algorithm, and compare its speed to that of the memoryless learning algorithm and of learning with memory (as analyzed in joint work with N. Komarova). We obtain precise results and show in particular that the batch learning algorithm is never worse than the memoryless learning algorithm (at least asymptotically). Its performance vis-a-vis learning with full memory is less clearcut, and depends on certainprobabilistic assumptions. These results necessitate theintroduction of the moment zeta function of a probability distribution and the study of some of its properties.
Yet another derivation of special relativity transformations without the second postulate  [PDF]
Josep Llosa
Physics , 2014,
Abstract: The most general transformation connecting inertial frames is derived from rather general and simple assumptions, without the postulate of constancy of the speed of light in vacuo.
Another Test of the Light Speed Invariance Postulate  [cached]
Stephan Joseph Gift
Modern Applied Science , 2011, DOI: 10.5539/mas.v5n6p152
Abstract: In a paper in 1910 Tolman pointed out that the light speed invariance postulate of special relativity requires that the time for light to traverse a fixed distance between two points is independent of the movement of those points relative to the light source. The range equation of the GPS is used to directly test this proposition. This equation has been rigorously tested and verified in the Earth-Centred Inertial frame where light signals propagate in straight lines at constant speed c. The result is a simple demonstration of light speed anisotropy that is consistent with light speed variation detected in other experiments and inconsistent with the light speed invariance postulate.
Another Facet of LIG Parsing  [PDF]
Pierre Boullier
Computer Science , 1996,
Abstract: In this paper we present a new parsing algorithm for linear indexed grammars (LIGs) in the same spirit as the one described in (Vijay-Shanker and Weir, 1993) for tree adjoining grammars. For a LIG $L$ and an input string $x$ of length $n$, we build a non ambiguous context-free grammar whose sentences are all (and exclusively) valid derivation sequences in $L$ which lead to $x$. We show that this grammar can be built in ${\cal O}(n^6)$ time and that individual parses can be extracted in linear time with the size of the extracted parse tree. Though this ${\cal O}(n^6)$ upper bound does not improve over previous results, the average case behaves much better. Moreover, practical parsing times can be decreased by some statically performed computations.
Study on Electromagnetic Transient Condition of EMU Passing by Phase-separation with Electric Load in High-speed Railway  [PDF]
Xiaoxu Guo, Jianzhong Wei, Long Xu, Shibin Gao, Zhengqing Han
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B202

Aiming at the complex electromagnetic transient process of EMU passing by phase-separation with electric load in high-speed railway, mechanism of overvoltage caused by switching off, overvoltage caused by switching on and impact current is analyzed systematically in this article. π-type equivalent circuit of feeding section is put forward in the analysis of overvoltage mechanism. Overvoltage and overcurrent model of passing by phase-separation with electric load are also built. Correctness of mechanism was validated by simulation. In addition, the methods to solve the influence on substations, transformers and protection devices in this process are put forward, which provides a new idea on passing by phase-separation with electric load technology.

Adjustments of Speed and Path when Avoiding Collisions with Another Pedestrian  [PDF]
Markus Huber, Yi-Huang Su, Melanie Krüger, Katrin Faschian, Stefan Glasauer, Joachim Hermsd?rfer
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0089589
Abstract: When walking in open space, collision avoidance with other pedestrians is a process that successfully takes place many times. To pass another pedestrian (an interferer) walking direction, walking speed or both can be adjusted. Currently, the literature is not yet conclusive of how humans adjust these two parameters in the presence of an interferer. This impedes the development of models predicting general obstacle avoidance strategies in humans’ walking behavior. The aim of this study was to investigate the adjustments of path and speed when a pedestrian is crossing a non-reactive human interferer at different angles and speeds, and to compare the results to general model predictions. To do so, we designed an experiment where a pedestrian walked a 12 m distance to reach a goal position. The task was designed in such a way that collision with an interferer would always occur if the pedestrian would not apply a correction of movement path or speed. Results revealed a strong dependence of path and speed adjustments on crossing angle and walking speed, suggesting local planning of the collision avoidance strategy. Crossing at acute angles (i.e. 45° and 90°) seems to require more complex collision avoidance strategies involving both path and speed adjustments than crossing at obtuse angles, where only path adjustments were observed. Overall, the results were incompatible with predictions from existing models of locomotor collision avoidance. The observed initiations of both adjustments suggest a collision avoidance strategy that is temporally controlled. The present study provides a comprehensive picture of human collision avoidance strategies in walking, which can be used to evaluate and adjust existing pedestrian dynamics models, or serve as an empirical basis to develop new models.
Measuring the Speed of Sound of Quintessence  [PDF]
Joel K. Erickson,R. R. Caldwell,Paul J. Steinhardt,C. Armendariz-Picon,V. Mukhanov
Physics , 2001, DOI: 10.1103/PhysRevLett.88.121301
Abstract: Quintessence, a time-varying energy component that may account for the accelerated expansion of the universe, can be characterized by its equation of state and sound speed. In this paper, we show that if the quintessence density is at least one percent of the critical density at the surface of last scattering the cosmic microwave background anisotropy can distinguish between models whose sound speed is near the speed of light versus near zero, which could be useful in distinguishing competing candidates for dark energy.
Yet another journal .  [cached]
Udwadia Tehemton
Journal of Minimal Access Surgery , 2005,
Yet another hysteresis model  [PDF]
Sergey Langvagen
Physics , 2001,
Abstract: A hysteresis model based on the assumption of fixed order magnetization reversals is proposed. The model uses one-dimensional diagram for representing states of a system despite of two-dimensional Preisach diagram. The distinctive feature of the model is that it is applicable to any system compliant with the return-point memory and includes Preisach model as a special case.
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