in this paper we introduce the notions of uniformly quasi-primary ideals and uniformly classical quasi-primary submodules that generalize the concepts of uniformly primary ideals and uniformly classical primary submodules; respectively. several characterizations of classical quasi-primary and uniformly classical quasi-primary submodules are given. then we investigate for a ring $r$, when any fi...

let $alpha$ be an endomorphism and $delta$ an $alpha$-derivationof a ring $r$.  in this paper we  study the relationship between an$r$-module $m_r$ and the  general polynomial module  $m[x]$ over theskew polynomial ring $r[x;alpha,delta]$. we introduce the notionsof skew-armendariz modules and skew quasi-armendariz modules whichare generalizations of $alpha$-armendariz modules and extend thecla...

This is the first paper in a series to study vertex algebra-like objects arising from infinite-dimensional quantum groups (quantum affine algebras and Yangians). In this paper we lay the foundation for this study. For any vector space W , we study what we call quasi compatible subsets of Hom(W,W ((x))) and we prove that any maximal quasi compatible subspace has a natural nonlocal (namely noncom...

The dynamic simulation system of a pantograph and a catenary has been built by using the finite element method, in which the pantograph is equivalent to a threemass-damper-stiffness system and the catenary contains only cable and beam elements. Considering droppers as nonlinear elements only stressed by tension, a sliding contact model of the pantograph and catenary is coupled by penalty functi...

An ultrasonic planar horn with a Bézier profile is developed. The first longitudinal displacement mode of the horn is exploited for high displacement amplification in order to reduce the penetration force required to enter and cut materials. The displacement amplification and stress distribution characteristics of the Bézier horn and the commonly used catenary horn are examined. The penetration...

The aim of this paper is to present an automatic, image-based system for catenary maintenance, a novel application of machine vision which has no equivalent today. This study focuses on the detection of droppers in catenary staves. The system takes benefit from the fact that dropper location inside catenary staves follows mounting rules, an information that is integrated into a top-down approac...

The architect Antonio Gaudi designed complex structures based on catenary systems. His beautiful forms were created by suspending pieces of string from hooks, deforming them with weights and other strings, then inverting the form to create the structural elements. Today’s architects are at a loss to reproduce these types of catenary forms when using even the most advanced design tools on the ma...

Contacts between pantograph and catenary are the most critical parts in the transmission of electrical energy for modern high-speed trains. Contact wire oscillations change combined force between pantograph and catenary, and the contact may even get lost. Therefore special pantographs and catenaries have been developed and further constructive changes are under development. A design criterion i...

Previous theoretical investigations of translating cables have been focused on the sagged cable equilibrium referred to here as the minimum cutenary. The minimum catenary is stable for finite translation speeds [ 1,2] and asymptotically approaches a buckling instability as the translation speed tends to infinity [2]. Experimental evidence presented in this paper validates this conclusion and th...

‎we characterize those groups $g$ and vector spaces $v$ such that $v$ is a faithful irreducible $g$-module and such that each $v$ in $v$ is centralized by a $g$-conjugate of a fixed non-identity element of the fitting subgroup $f(g)$ of $g$‎. ‎we also determine those $v$ and $g$ for which $v$ is a faithful quasi-primitive $g$-module and $f(g)$ has no regular orbit‎. ‎we do use these to show in ...