China 
Africa 
Explore chapters and articles related to this topic
Image Segmentation
Published in Vipin Tyagi, Understanding Digital Image Processing, 2018
An isolated point can be defined as a point which has an intensity level significantly different from its neighbors and is located in a homogeneous or nearly homogeneous area. An isolated point can be detected using masks, as shown in Fig. 7.2. A point is detected using mask processing if, at the location on which the mask is centered, the processed value is greater than some non-negative threshold. Basically, in this process, weighted differences between the center point and its neighbors are measured. An isolated point will be quite different from its surroundings in terms of its intensity value, and, thus, can easily be singled out using this type of mask.
Continuity and Topology
Published in James K. Peterson, Basic Analysis II, 2020
Comment 6.1.3If p is an isolated point of D, then the constant sequence {xn =p} in D converges to p and so p is a limit point of D. However, an isolated point isnotan accumulation point or cluster point.
Inner synchronisation of stochastic impulsive multi-links coupled systems via discrete-time state observations control
Published in International Journal of Control, 2021
Yan Liu, Anran Liu, Dianhui Chu, Huan Su
In this section, we will apply our results to Rössler-like circuits. Rössler-like circuits have been a hot research topic for their extensive applications (Heagy et al., 1994; Xiao et al., 2012). In reality, stochastic and impulsive effects are inevitable, however, there are few studies about SICRMC. Thus, this section mainly focuses on this kind of models. To begin with, an isolated point system is described by in which and π is a constant, are positive constants. Regarding each Rössler-like circuit as a vertex system, considering FCDSO and multiple links, the controlled system is designed as Let , and . Then the error system can be modelled as
A type of shadowing and distributional chaos
Published in Dynamical Systems, 2021
Following [18], we recall a simplified version of Mycielski's theorem ([23, Theorem 1]). A topological space is said to be perfect if it has no isolated point. A subset S of X is said to be a Mycielski set if it is a union of countably many Cantor sets.
Persistence and expansivity through pointwise dynamics
Published in Dynamical Systems, 2021
Let M be a totally disconnected minimal set with respect to f. Suppose that with expansivity constant . Note that if M contains an isolated point under subspace topology, then M and hence contains a periodic point of f which is a contradiction to Lemma 5.6. Therefore, M contains infinitely many elements. Since is an open subset of , we can write as a countable pairwise disjoint union of open arcs in . Note that , where , for a subset . Since M is totally disconnected, . From Remark 5.1(3), we can choose a such that , for some . From Theorem 1.6 and Remark 5.1(2), we get that , for each . Let be an expansive constant for uniform expansivity of f at y such that . Using similar arguments as given in [1, Paragraph 2 of page no. 56], we get that for each , we can choose two distinct points such that , for each , where denotes the arc contained in with ‘u’ and ‘v’ as its endpoints which is a contradiction to the uniform expansivity of f at y and hence we conclude that .