The paper deals with an M/M/2 Queueing Model working vacations and reneging of customers due to impatience. matrix geometric method is used find the distribution number in system. A cost function constructed obtain optimal value service rate optimize (minimize) using Quadratic Fit Search Method (QFSM). Further, effects on system's performance measures numerical analysis graphical representation...

in this paper we introduce strongly $left[  v_{2},lambda_{2},m,pright]-$summable double vsequence spaces via orlicz function and examine someproperties of the resulting these spaces. also we give natural relationshipbetween these spaces and $s_{lambda_{2}}-$statistical convergence.