Real-time routing is a basic element of closed-loop, real-time sensing and control, but it is very challenging due to dynamic, uncertain link/path delay. A basis of real-time routing is determining probabilistically guaranteed path delays, but this problem is NP-hard and it may well have to be solved by resource-constrained devices in a distributed manner; the highly varying nature of link/path...

We show by construction that the procedure of local search for the problem of finding a local optimum of a quadratic pseudo-boolean function takes exponential time in the worst case, regardless of the neighbor selection and tie-breaking rules.

We tackle the problem of non-preemptive scheduling of a set of tasks of duration p over m machines with given release and deadline times. We present a polynomial time algorithm as a generalization to this problem, when the number of machines fluctuates over time. Further, we consider different objective functions for this problem. We show that if an arbitrary function cost ci(t) is associated t...

In this paper we consider the local access telecommunication network expansion problem, in which growing demand can be satis®ed by expanding cable capacities and/or installing concentrators in the network. The problem is known to be NP-hard. We prove that the problem is weakly NP-hard, and present a pseudo-polynomial dynamic programming algorithm for the problem, with time complexity O…nB2† and...

Owing to several applications in large scale learning and vision problems, fast submodular function minimization (SFM) has become a critical problem. Theoretically, unconstrained SFM can be performed in polynomial time [10, 11]. However, these algorithms are typically not practical. In 1976, Wolfe [22] proposed an algorithm to find the minimum Euclidean norm point in a polytope, and in 1980, Fu...

Background: Water pollution is an important environmental problem, undoubtedly, the presence of toxic heavy metals forms the main source of water contamination. Sorption characteristics of polyurethane foams modified with bis (2-ethylhexyl)phosphoric acid (DEHPA) for the removal of zinc, lead and cadmium ions from contaminated solutions were investigated. Methods: Operating variables, such as ...