‎In this paper‎, ‎we characterize the class of orthogonality preserving operators on an infinite-dimensional Hilbert space $H$ as scalar multiples of unitary operators between $H$ and some closed subspaces of $H$‎. ‎We show that any circle (centered at the origin) is the spectrum of an orthogonality preserving operator‎. ‎Also‎, ‎we prove that every compact normal operator is a strongly orthogo...

Suppose that A is a C^*-algebra. We consider the class of A-linear mappins between two inner product A-modules such that for each two orthogonal vectors in the domain space their values are orthogonal in the target space. In this paper, we intend to determine A-linear mappings that preserve orthogonality. For this purpose, suppose that E and F are two inner product A-modules and A+ is the set o...

An extension of the metric space in which distance same point is not always zero called a partial space. Orthogonality relation two perpendicular lines at one intersection forming right angle. There are several ways to define orthogonality, including Pythagorean Orthogonality, Isosceles and Birkhoff-James Orthogonality. The purpose this research study consistency definition orthogonality Based ...

For a bounded linear operator on Hilbert space we define a sequence of the so-called weakly extremal vectors‎. ‎We study the properties of weakly extremal vectors and show that the orthogonality equation is valid for weakly extremal vectors‎. ‎Also we show that any quasinilpotent operator $T$ has an hypernoncyclic vector‎, ‎and so $T$ has a nontrivial hyperinvariant subspace‎.

in this paper, we consider orthogonal stability of mixed type additive and cubic functional equation of the form $$f(2x+y)+f(2x-y)-f(4x)=2f (x+y)+2f(x-y)-8f(2x) +10f(x)-2f(-x),$$ with $xbot y$, where $bot$  is orthogonality in the sense of ratz.

Application of Random Indexing (RI) to extractive text summarization has already been proposed in literature. RI is an approximating technique to deal with high-dimensionality problem of Word Space Models (WSMs). However, the distinguishing feature of RI from other WSMs (e.g. Latent Semantic Analysis (LSA)) is the near-orthogonality of the word vectors (index vectors). The near-orthogonality pr...

space 1 The space of twist Joint space The space of wrench (6) jT T T J ~ ( = J KI Ii) I ' * 1 v torque space 1 Figure 2.6: Transformation from Task Domain to Joint Domain where each column of J is the image in abstract space of the corresponding column of the Jacobian J . Thus. the base of the joint variable space is: and the base of the joint torque space is: Because J is a matrix defined in ...