We study algorithmic and structural aspects of connectivity in hypergraphs. Given a hypergraph H = (V, E) with n= |V |, m= |E| and p = ∑ e∈E |e| the fastest known algorithm to compute a global minimum cut in H runs in O(np) time for the uncapacitated case, and in O(np+ n2 log n) time for the capacitated case. We show the following new results. • Given an uncapacitated hypergraph H and an intege...

We introduce the Mixed Capacitated General Routing Problem with Time Windows (MCGRPTW). This problem is defined over a mixed graph, for which some nodes, arcs and edges have strictly positive demand and must be serviced through a fleet of homogeneous capacitated vehicles. The aim is to find a set of least-cost vehicle routes that satisfy this requirement, while respecting pre-specified time win...

In recent years, the capacitated center problems have attracted a lot of research interest. Given a set of vertices V , we want to find a subset of vertices S, called centers, such that the maximum cluster radius is minimized. Moreover, each center in S should satisfy some capacity constraint, which could be an upper or lower bound on the number of vertices it can serve. Capacitated k-center pr...

We consider uncapacitated and capacitated assortment problems under the paired combinatorial logit model, where the goal is to find a set of products to maximize the expected revenue obtained from each customer. In the uncapacitated setting, we can offer any set of products, whereas in the capacitated setting, there is a limit on the number of products that we can offer. We establish that even ...

When mammalian spermatozoa become capacitated they acquire, among other activities, chemotactic responsiveness and the ability to exhibit occasional events of hyperactivated motility--a vigorous motility type with large amplitudes of head displacement. Although a number of roles have been proposed for this type of motility, its function is still obscure. Here we provide evidence suggesting that...

The k-center problem is a classic facility location problem, where given an edge-weighted graph G = (V,E) one is to find a subset of k vertices S, such that each vertex in V is “close” to some vertex in S. The approximation status of this basic problem is well understood, as a simple 2-approximation algorithm is known to be tight. Consequently different extensions were studied. In the capacitat...

BACKGROUND Mammalian spermatozoa have been shown to have beta(1,2,3)- and alpha(2A)-adrenergic receptors, the former functioning only in uncapacitated spermatozoa and the latter only in capacitated cells. Cathine, an amphetamine-related metabolite of a compound found in Catha edulis leaves, accelerates capacitation and inhibits spontaneous acrosome loss by regulating cAMP production. This study...

The talk presents two non-standard extensions for singlevehicle arc-routing problems a.k.a. postman problems: First, street segments that require a service on both sides of the street can be covered either by two separate services or by a single zigzag service. Instead of deciding the type of service beforehand, we propose to take into account the zigzagging option when designing a tour. We pre...

the capacitated vehicle routing problem (cvrp) is a well-known combinatorial optimization problem that holds a central place in logistics management. the vehicle routing is an applied task in the industrial transportation for which an optimal solution will lead us to better services, save more time and ultimately increase in customer satisfaction. this problem is classified into np-hard problem...

the capacitated clustering problem (ccp) is one of the most importantcombinational optimization problems that nowadays has many real applications inindustrial and service problems. in the ccp, a given n nodes with known demandsmust be partitioned into k distinct clusters in which each cluster is detailed by anode acting as a cluster center of this cluster. the objective is to minimize the sumof...