We introduce a Laplacian for the distance matrix of a connected graph, called the <i>distance Laplacian</i> and we study its spectrum. We show the equivalenc...

In 1956, Nordhaus and Gaddum gave lower and upper bounds on the sum and the product of the chromatic number of a graph and its complement, in terms of the or...

The Job Grouping Problem consists of assigning a set of jobs, each with a specific set of tool requirements, to machines with a limited tool capacity in orde...

Column generation for solving linear programs with a huge number of variables alternately solves a (restricted) master problem and a pricing subproblem to ad...

The min-max <i>k</i>-vehicles windy rural postman problem consists of minimizing the maximal distance traveled by a vehicle in order to find a set of b...

Modularity maximization is extensively used to detect communities in complex networks. It has been shown however that this method suffers from a resolution l...

We study the problem of packing equal circles in a square from the mathematical programming point of view. We discuss different formulations, we analyse fo...

In a recent paper, Zhan, Zhang, Guan, and Zhou [Phys. Rev. E <b>83</b>, 066120 (2011)] presented a modified adaptive genetic algorithm (MAGA) tailored to the...

We present a branch-price-and-cut method to solve a maritime pickup and delivery problem with time windows and split loads. The fleet of ships is heterogen...

In chemical graph theory, many graph parameters, or topological indices, were proposed as estimators of molecular structural properties. Often several varian...

Operational problems arising in the planning of integrated supply chains have been increasingly studied in the past decade. Among these, the production rout...

It is well known that some local search algorithms for <i>K</i>-clustering problems could stop at a solution with fewer clusters than the desired <i>K</i>....

Given a graph <i>G</i> and a bipartition of its vertices, the edge-ratio is the minimum for both classes so defined of their number of internal edges divid...

In the service industry, the employees perform work shifts and are assigned to interruptible activities and uninterruptible tasks during their shifts. The ...

We consider a cement delivery problem with an heterogeneous fleet of vehicles and several depots. The demands of the customers are typically larger than the ...

The objective in the continuous facility location problem with limited distances is to minimize the sum of distance functions from the facility to the cust...

The GRIEG model is a hybrid model of demo-economic projections that combines two approaches: the econometric approach - based on the micro-economy - of the N...

Community detection in networks based on modularity maximization is currently done with hierarchical divisive or agglomerative as well as with partitioning h...

Heuristics are widely applied to modularity maximization models for the identification of communities in complex networks. We present an approach to be appli...

In this paper we study a variant of the Capacitated Team Orienteering Problem (CTOP), that is the problem where a fleet of vehicles, each with a constraint...