We compare the performance of seven methods in computing or approximating service levels for nonstationary M(t)/M/s(t) queueing systems: an exact method (a Runge-Kutta ordinary-differential-equation solver), the randomization method, a closure (or surrogate-distribution) approximation, a direct...

Achieving the ambitious Global Methane Pledge announced in the Glasgow Climate Pact requires collaborative efforts from both the signatory countries and China which serves as the world’s largest emitter. Considering the heterogeneity of economic structures within China and the relocation of...

The network design problem with relays (NDPR) is defined on an undirected graph G = (V, E, K), where V = {1, … , n} is a vertex set, E = {(i, j) : i, j ∈ V, i j} is an edge set. The set K = {(o(k), d(k))} is a set of communication pairs (or commodities): o(k) ∈ V and d(k) ∈ V denote the...

As Internet technologies for long-distance transmission fall in price, and the volume of data transmission surpasses that of voice transmission, networks developed solely for the Internet are becoming the trend. However, long-distance Internet technologies add considerable delay to the signal...

The performance of a process control algorithm based on EWMA statistic is analyzed. A simple condition relating the EWMA weight and the estimated process gain is shown to ensure that the control strategy is stable for a first-order multiple-input, single-output process that may be drifting or...

Monte Carlo simulation models of regular season and playoff games in the National Hockey League can be used to motivate students who are sports fans to study OR/MS models. I describe how such models can be implemented in a spreadsheet, how my colleagues and I have used them in our courses, and...

Graphical representations of spreadsheet queueing simulations can be used to teach students about queues and queueing processes. A customer graph shows the experience of every individual customer in a queue, based on arrival time, start of service, end of service, and showing clearly the length...