We analyze a single server queue with Poisson arrivals, two stages of heterogeneous service with different (arbitrary) service time distributions subject to random breakdowns and compulsory server vacations with general (arbitrary) vacation periods. After first-stage service the server must provide the second stage service. However, after the completion of each second stage service, the server ...

We consider an M/GI/1/N queue with vacation time and exhaustive service discipline, the same queue as in Lee 9]. Focusing only on the service completion epochs (as oposed to both service completion epochs and vacation completion epochs by Lee), we present a simple analysis for the queue length distribution at an arbitrary time as well as for the waiting time distribution.

The traveling salesman problem (TSP) is a well-known optimization problem in graph theory, as well as in operations research that has nowadays received much attention because of its practical applications in industrial and service problems. In this problem, a salesman starts to move from an arbitrary place called depot and after visits all of the nodes, finally comes back to the depot. The obje...

Differentiation is an important task in control, observation, and fault detection. Levant’s differentiator unique, since it able to estimate exactly robustly the derivatives of a signal with bounded high-order derivative. However, convergence time, although finite, grows unboundedly norm initial differentiation error, making uncertain when estimated derivative exact. In this article, we propose...

We propose a conceptually novel method of reconstructing the topology of dynamical networks. By examining the correlation between the variable of one node and the derivative of another node’s variable, we derive a simple matrix equation yielding the network adjacency matrix. Our assumptions are the possession of time series describing the network dynamics, and the precise knowledge of the inter...

We introduce and study an eigenvalue upper bound p(G) on the maximum cut mc (G) of a weighted graph. The function ~o(G) has several interesting properties that resemble the behaviour of mc (G). The following results are presented. We show that q~ is subadditive with respect to amalgam, and additive with respect to disjoint sum and 1-sum. We prove that ~(G) is never worse that 1.131 mc(G) for a ...

We consider a single server queuing system with repeated attempts in which customers arrive according a Markov arrival process (MAP) and with a LCFS PR discipline. The service times are independent and have a common general distribution. After service completion time the server initiates his search time with an arbitrary distribution function. We consider two cases where the maximum number of r...

An approximation technique is considered for computing transmission and reflection coefficients for plane waves propagating through stratified slabs. The propagation of elastic pulse through a planar slab is derived from first principles using straightforward time-dependent method. The paper ends with calculations of enhancement factor for the elastic plane wave and it is shown that it depends ...

The MX/G/1 queue with finite waiting room is studied for both the partially rejected model and the totally rejected model. We start by studying the joint distribution of the number of customers at time t and the remaining service time of customer in service. This gives the asymptotic distribution of the number of customers at an arbitrary moment and immediately after a departure. Also the waiti...