We show that Preissmann’s theorem implies that no closed negatively curved manifold is dominated by a non-trivial product. We also show that a fiber bundle whose base and fiber are negatively curved is dominated by a product if and only if it has a finite covering space which is a trivial bundle.

The paper addresses the problem of stabilizing discrete-time systems subject to time varying polytopic uncertainty. Non stationary quadratic Lyapunov functions are derived for synthesis in a Poly-Quadratic Lyapunov function concept which avoids in a large extent the conservatism linked with the classical single Lyapunov function quadratic approach. The state space feedback synthesis problem is ...

Let X− be a compact complex manifold with a strictly pseudoconcave boundary. We consider the following questions: Question 1: When does there exist a compact complex manifold V such that X− embeds into V as an open set? If such a V can be found then we say that X− is fillable. If dimX− ≥ 3 then using a result of Rossi we know that this can always be done, see [7]. However if dimX− = 2 then ther...

In this paper, first the space of hyperbolic tangent functions is introduced and then the universal approximator property of this space is proved. In fact, by using this space, any nonlinear continuous function can be uniformly approximated with any degree of accuracy. Also, as an application, this space of functions is utilized to design feedback control for a nonlinear dynamical system.

Let A be a bounded linear operator on a Banach space X. We investigate the conditions of existing rank-one operator B such that I+f(A)B is invertible for every analytic function f on sigma(A). Also we compare the invariant subspaces of f(A)B and B. This work is motivated by an operator method on the Banach space ell^2 for solving some PDEs which is extended to general operator space under some ...

Nowadays there are different kinds of attacks on Field Programmable Gate Array (FPGA). As FPGAs are used in many different applications, its security becomes an important concern, especially in Internet of Things (IoT) applications. Hardware Trojan Horse (HTH) insertion is one of the major security threats that can be implemented in unused space of the FPGA. This unused space is unavoidable to ...

statement of problem: nowadays, evaluation of the development of occlusion in deciduous teeth for creating corrective occlusion in permanent teeth is one of the most important objectives of pediatric dentistry. in other countries, a vast number of researches have been accomplished on the details of occlusion in deciduous teeth. but, unfortunately, there is still no accurate information about th...

a reproducing kernel hilbert space restricts the space of functions to smooth functions and has structure for function approximation and some aspects in learning theory. in this paper, the solution of an integral equation of the third kind is constructed analytically using a new method. the analytical solution is represented in the form of series in the reproducing kernel space. some numerical ...

We first obtain some properties of a fundamentally nonexpansive self-mapping on a nonempty subset of a Banach space and next show that if the Banach space is having the Opial condition, then the fixed points set of such a mapping with the convex range is nonempty. In particular, we establish that if the Banach space is uniformly convex, and the range of such a mapping is bounded, closed and con...