In this work, we analyse a pair of two-dimensional coupled reaction-diusion equations known as the Gray-Scott model, in which spot patterns have been observed. We focus on stationary patterns, and begin by deriving the asymptotic scaling of the parameters and variables necessary for the analysis of these patterns. A complete bifurcation study of these solutions is presented. The main mathematic...

Ancient origins of a modern anthropic argument against cosmologies involving infinite series of past events are considered. It is shown that this argument – which in modern times has been put forward by distinguished cosmologists such as Paul C. W. Davies and Frank J. Tipler – originates in pre-Socratic times and is implicitly present in the cyclical cosmology of Empedocles. There are traces of...

Bearing failure is one of the dominant causes of failure and breakdowns in rotating machinery, leading to huge economic loss. Aiming at the nonstationary and nonlinear characteristics of bearing vibration signals as well as the complexity of condition-indicating information distribution in the signals, a novel rolling element bearing fault diagnosis method based on multifractal theory and gray ...

background: jaw bone quality plays an essential role in treatment planning and prognosis of dental implants. regarding several available methods for bone density measurements, they are not routinely used before implant surgery due to hard accessibility. objective: an in vitro investigation of correlation between average gray scale in direct digital radiographs and hounsfield units in ct-scan pr...

in the achromatic neon effect'' by Marc K Albertô Albert (1998) describes a number of visual displays, which he uses to argue against current models of neon color spreading. He particularly emphasizes models which I and my colleagues have developed. He erroneously concludes that our models cannot explain the percepts that are generated by these displays. I am writing to set the record straight....

Vehicle information on high-speed trains can not only determine whether the various parts of train are working normally, but also predict train's future operating status. How to obtain valuable from massive vehicle data is a difficult point. First, we divide into 13 subsystem datasets, according functions collection components. Then, gray theory and Granger causality test, propose Gray-Granger ...