a famous theorem of schur states that for a group $g$ finiteness of $g/z(g)$‎ ‎implies the finiteness of $g'.$ the converse of schur's theorem is an interesting problem which has been considered by some‎ ‎authors‎. ‎recently‎, ‎podoski and szegedy proved the truth of the converse of schur's theorem for capable groups‎. ‎they also established an explicit bound for the index of the center of such...

in this paper, we investigate the delay-dependent robust stability of fuzzy cohen-grossberg neural networks with markovian jumping parameter and mixed time varying delays by delay decomposition method. a new lyapunov-krasovskii functional (lkf) is constructed by nonuniformly dividing discrete delay interval into multiple subinterval, and choosing proper functionals with different weighting matr...

Abstract—This paper is concerned with the reliable H∞ filtering problem against sensor failures for a class of continuoustime systems with simultaneous sector-bounded nonlinearities and varying time delay. The resulting design is such that the filtering error system is asymptotically stable and meets the prescribed H∞ norm constraint in the nominal case as well as in the sensor failure case. A ...

We study a long standing open problem on the mixing time of Kac’s random walk on SO(n,R) by random rotations. We obtain an upper bound mix = O(n log n) for the weak convergence which is close to the trivial lower bound Ω(n). This improves the upper bound O(n log n) by Diaconis and Saloff-Coste [9]. The proof is a variation on the coupling technique we develop to bound the mixing time for compac...

In validated branch and bound algorithms for global optimization, upper bounds on the global optimum are obtained by evaluating the objective at an approximate optimizer; the upper bounds are then used to eliminate subregions of the search space. For constrained optimization, in general, a small region must be constructed within which existence of a feasible point can be proven, and an upper bo...

in forging design the significant parameters are maximum load or energy which are required for the selection of forging press or hammer. these two parameters are varied by the other paramelers such as the geometry of die cavity, flash dimensions, shape of the work piece, friction, mechanical properties of the metal to be forged, temperature, strain rate, and number of the forging operation. the...

We study the bifurcation of limit cycles from the periodic orbits of a four-dimensional center in a class of piecewise linear differential systems. Our main result shows that three is an upper bound for the number of limit cycles that bifurcate from a center, up to first order expansion of the displacement function. Moreover, this upper bound is reached. The main technique used is the Averaging...

We prove that any irreducible triangulation on n vertices has O(4.6807) regular edge labelings and that there are irreducible triangulations on n vertices with Ω(3.0426) regular edge labelings. Our upper bound relies on a novel application of Shearer’s entropy lemma. As an example of the wider applicability of this technique, we also improve the upper bound on the number of 2-orientations of a ...

In this paper, we investigate the delay-dependent robust stability of fuzzy Cohen-Grossberg neural networks with Markovian jumping parameter and mixed time varying delays by delay decomposition method. A new Lyapunov-Krasovskii functional (LKF) is constructed by nonuniformly dividing discrete delay interval into multiple subinterval, and choosing proper functionals with different weighting matr...