Team Orienteering with Decreasing Profits (DP-TOP) extends the classical Team Orienteering problem (TOP) by considering the profit of each client as a decreasing function of time. It consists of maximizing the sum of collected profit by a fixed number K of vehicles, visiting each client at most once. In this work, we present lower bounds based on a Dantzig-Wolfe decomposition and column generat...

Recommender systems have been widely used in e-commerce applications. They are a subclass of information filtering system, used to either predict whether a user will prefer an item (prediction problem) or identify a set of k items that will be user-interest (Top-k recommendation problem). Demanding sufficient ratings to make robust predictions and suggesting qualified recommendations are two si...

We want to study the perturbation growth of an initial seed of an ellipsoidal shape in Top-Hat collapse model of the structure formation in the Modied Chaplygin gas cosmology. Considering reasonable values of the constants and the parameters of the model under study, we can show that a very small deviation from spherical symmetry (ellipsoidal geometry) in the initial seed leads to a nal highly ...

because of the role of climate parameters in climate change and improve the efficiency of climate and rainfall prediction models, the study of these parameters are very important in the world. the study of clouds have special important, because the clouds make connection between the synoptic patters and surface climate conditions and any change in its properties, can start a chain reaction in o...

Facing an increasing violence level and higher firepower in the hands of criminal organizations (especially those related to drug trafficking), the Military Police of Pernambuco has created, in 1989, the "1a Companhia Independente de Operações Especiais" (1st Independent Company of Special Operations), as a tactical last resort of the Police to be used on special, complex situations. The CIOE p...

An automatic classification scheme of on-line handwritten signatures is presented. A Multilayer Perceptron (MLP) with a hidden layer is used as classifier, and two different signature classes are considered, namely: legible and non-legible name. Signatures are represented considering different feature subsets obtained from global information. Mahalanobis distance is used to rank the parameters ...