We prove that the problem of deciding whether a graph has a balanced skew partition is NP-hard. We give an O(n9)-time algorithm for the same problem restricted to Berge graphs. Our algorithm is not constructive : it certifies that a graph has a balanced skew partition if it has one. It relies on...

We give a structural description of the class C of graphs that do not contain a cycle with a unique chord as an induced subgraph. Our main theorem states that any connected graph in C is a either in some simple basic class or has a decomposition. Basic classes are cliques, bipartite graphs with...

An s-graph is a graph with two kinds of edges : subdivisible edges and real edges. A realisation of an s-graphB is any graph obtained by subdividing subdivisible edges of B into paths of arbitrary length (at least one). Given an s-graph B, we study the decision problem Pi(B) whose instance is a...

The recent fi nancial crisis has lead the IASB to settle new reporting standards for fi nancial instruments. The extended ability to measure some debt instruments at amortized cost is associated with a new impairment losses mechanism: Expected Credit Losses. In this paper, after a brief...

Nous proposons d'analyser l'intégration des connaissances à la source d'un avantage concurrentiel avec une approche pratique des organisations. Alors que la littérature s'est focalisée sur le transfert de connaissances et les relations entre communautés par le biais des objets frontière,...

Nous proposons de définir la production d'idées comme une pratique, c'est-à-dire comme une activité qui prend son sens et sa valeur dans un contexte social, pour analyser le travail créatif dans les cuisines de trois grands restaurants.

In time series analysis, most estimation of relationships and tests are typically based on linear estimators and most classical co-integration methods and causality tests are based on OLS regresses. However the linear functional specification is not necessarily the most appropriate form. This...

Forecasting in a risky situation is a very important function for managers to assist in decision making. One of the fluctuated markets in stock exchange market is chemical market. In this research the target item for prediction is PET (Poly Ethylene Terephthalate) which is the raw material for...

Nowadays, forecasting what will happen in economic environments plays a crucial role. We showed that in PET market how a neuro-fuzzy hybrid model can assist the managers in decision-making. In this research, the target is to forecast the same item through another intelligent tool which obeys the...