We exploit the techniques developed in [Le] to study N -expansive homeomorphisms on surfaces. We prove that when f is a 2-expansive homeomorphism defined on a compact boundaryless surface M with nonwandering set Ω(f) being the whole of M then f is expansive. This condition on the nonwandering set cannot be relaxed: we present an example of a 2-expansive homeomorphisms on a surface with genus 2 ...

begin{abstract} In this paper, we introduce an iterative method for amenable semigroup of non expansive mappings and infinite family of non expansive mappings in the frame work of Hilbert spaces. We prove the strong convergence of the proposed iterative algorithm to the unique solution of a variational inequality, which is the optimality condition for a minimization problem. The results present...

Subshifts are sets of configurations over an infinite grid defined by a set of forbidden patterns. In this thesis, we study two-dimensional subshifts of finite type (2D SFTs), where the underlying grid is Z and the set of forbidden patterns is finite. We are mainly interested in the interplay between the computational power of 2D SFTs and their geometry, examined through the concept of expansiv...

an efficient synthesis route to 1,4-dihydropyrimidine derivatives from reaction of divergent aldehydes with ethylacetoacetate and urea under solvent-free conditions by zno nanoparticles as a relative in expansive, eco-friendly, easy available, non-volatile, non-explosion, thermally robust, recyclable and easy to handle catalyst at 90°c with excellent yields is described. unenhanced reaction tim...

Engineering problems shunned previously rise to the surface gradually with the activities of reforming the natural world in depth, the problem of expansive soil crack under the changing environment becoming a control factor of expansive soil slope stability. The problem of expansive soil crack has gradually become a research hotspot, elaborates the occurrence and development of cracks from the ...

The first stage of any major civil engineering project generally involves some form of preliminary reconnaissance study of project sites followed by detailed geotechnical investigation. Primary aim of this study is to collect data concerning physical characteristics of terrain and ground conditions in order to assess their likely influence on the overall design and performance of infrastructure...

Expansive soils swell when they absorb water and shrink when water evaporates from them. Hence, lightly loaded civil engineering structures founded in these soils are subjected to severe distress. Therefore, there is a need to ameliorate or improve these swelling soils through some innovative methods. This paper discusses chemical stabilisation of expansive soils, a technique in which chemical ...

The major decision in construction process involves the selection of suitable site with best soil conditions, as structure resides in the soil. Most problematic soils like expansive soils hardly proved to be the best engineering subgrade profile for pavement constructions. Thus, this has undeniably led to the soil improvement options accompanying the reduction in resource depletion and solid wa...

The paper examines studies based on the theory of expansive learning, formulated in 1987. In recent years the theory has been used in a wide variety of studies and interventions. The theory builds on foundational ideas put forward by Vygotsky, Leont’ev, Il’enkov, and Davydov, key figures in the Russian school of cultural–historical activity theory. Studies based on the theory are reviewed in si...