We consider the maximal covering location-allocation problem with multiple servers. The objective is to maximize the population covered, subject to constraints on the number of service centers, total number of servers in all centers, and the average waiting time at each center. Each center operates as an M/M/k queuing system with variable number of servers. The total costs of establishing cen...

The present paper aims to investigate the role of open metal site metal-organic frameworks (MOFs) on hydrogen adsorptivity using periodic boundary condition (PBC) density functional theory (DFT). Hence, MIL-47-M (M = V and Fe) were selected and one hydrogen molecule adsorptivity was calculated in different orientations on them. Four different chemical sites were identified in every cluster sect...

This paper deals with multi-component machine repair model having provision of warm standby units and repair facility consisting of two heterogeneous servers (primary and secondary) to provide repair to the failed units. The failure of operating and standby units may occur individually or due to some common cause. The primary server may fail partially following full failure whereas secondary se...

We consider a generalization E(n) of the Johnson-Wilson spectrum E(n) for which E(n)∗ is a local ring with maximal ideal In. We prove that the spectra E(n), E(n) and[ E(n) are Bousfield equivalent. We also show that the Hopf algebroid E(n)∗E(n) is a free E(n)∗-module, generalizing a result of Adams and Clarke for KU∗KU .