In this paper, we consider a multi-server queuing system in which additional servers are allowed for a longer queue to reduce the customer’s balking and reneging behavior. The customers are assumed to arrive in Poisson fashion and their service- times follow exponential distribution. The number of servers in long run depends on the queue-length. We obtain equilibrium queue size distribution. Th...

the effects of allopurinol, acyclovir and theophylline on the activity of adenosine deaminase (ada) were studied in 50 mm sodium phosphate buffer ph 7.5 at 27°c, using a uv– vis spectrophotometer. adenosine deaminase is inhibited by these ligands, via different types of inhibition. allopurinol, as a transition state analog of xanthine oxidase, and acyclovir competitively inhibit the catalytic a...

In this study, the effect of 1,2,3-trichloropropane (TCP) as trifunctional monomer on thermophysical properties of synthesized poly(ethylene tetrasulfide) (PETS) is investigated. To this end, different amounts of TCP (0-40 mol. % of halide-containing monomer) were incorporated into the structure of polysulfide polymer via interfacial condensation polymerization. Measuremen...

It was shown that the structure and particle size of zirconia nanoparticles has been controlled through the homogeneous precipitation process by using templates. Hexamine as the template led to ZrO2 nanoparticles with tetragonal structure, whereas coffee extract favored monoclinic structures. Field Emission Scanning electron microscopy (FeSEM), Transmission electron microscopy (TEM) measurement...

The M-tree is a dynamic data structure designed to index metric datasets. In this paper we introduce two dynamic techniques of building the M-tree. The first one incorporates a multi-way object insertion while the second one exploits the generalized slim-down algorithm. Usage of these techniques or even combination of them significantly increases the querying performance of the M-tree. We also ...

Given a set of axis-aligned boxes B = {B1, B2, . . . , Bn} and a set of points P = {p1, p2, . . . , pm} in d-space, let the discrete measure of B with respect to P be defined as meas(B,P) = |P ∩ { ⋃n i=1Bi}|, namely, the number of points of P contained in the union of boxes of B. This is a discrete and dynamic version of Klee’s measure problem, which asks for the Euclidean volume of a union of ...