Context: Magnetic null points are associated with high-energy coronal phenomena such as solar flares and often sites of reconnection particle acceleration. Dynamic twisting a magnetic point can generate Kelvin-Helmholtz instability (KHI) within its fan plane and, under continued twisting, instigate spine-fan an collapse the point. Aim: This article aims to compare effects isotropic anisotropic ...

We present a new MHD wave decomposition method that overcomes the limitations of existing identification methods. Our allows to investigate energy fluxes in different modes at locations solar atmosphere as waves generated by vortex flows travel through and pass near magnetic null. simulate dynamics coronal null configuration apply rotational driver our bottom photospheric boundary. To identify ...

Let S1 = {Ft}t≥0 and S2 = {Gt}t≥0 be two continuous semigroups of holomorphic self-mappings of the unit disk ∆ = {z : |z| < 1} generated by f and g, respectively. We present conditions on the behavior of f (or g) in a neighborhood of a fixed point of S1 (or S2), under which the commutativity of two elements, say, F1 and G1 of the semigroups implies that the semigroups commute, i.e., Ft◦Gs = Gs◦...

We present sufficient conditions for sums of dependent point processes to converge in distribution to a Poisson process. This extends the classical result of Grigelionis [Theory Probab. Appl. 8 (1963) 172– 182] for sums of uniformly null point processes that have Poisson limits. Included is an application in which a particle-survivor point process converges to a Poisson process. This result she...

Abstract. A new topic of great relevance and concern has been the design of efficient early warning systems to detect as soon as possible the emergence of spatial clusters. In particular, many applications involving spatial events recorded as they occur sequentially in time require this kind of analysis, such as fire spots in forest areas as in the Amazon, crimes occurring in urban centers, loc...

This paper deals with the problem of testing hypothesis when both the hypotheses and the available data are fuzzy. First, four different kinds of fuzzy hypotheses are defined. Then, a procedure is developed for constructing the fuzzy point estimation based on fuzzy data. Also, the concept of fuzzy test statistic is defined based on the α-cuts of the fuzzy null hypothesis and the α-cuts of the c...