Tabu search for a parallel-machine scheduling problem with periodic maintenance,job rejection and weighted sum of completion times

Journal of Scheduling - We consider in this work a bicriteria scheduling problem on two different parallel machines with a periodic preventive maintenance policy. The two objectives considered...     

Liver Transplantation for Colorectal Liver Metastases: Current Management and Future Perspectives

Patients with nonresectable liver metastases from colorectal cancer have few therapeutic options and a dismal prognosis. Although liver transplantation for this indication has historically a poor reputation, recent advances in the field of chemotherapy and immunosuppression have paved the way to revisit the concept. New data have shown promising results that need to be validated in several ongoing clinical trials. Since liver grafts represent a scarce resource, several new tools are being explored to expand the donor pool for this indication. The purpose of this review is to present all current available data and perspectives about liver transplantation for nonresectable liver metastases from colorectal cancer.     

Comparison of surfaces properties of different types of cotton fibers by inverse gas chromatography

Three types of cotton fibers of different varieties and exhibiting different maturities and wax contents were examined by inverse gas chromatography (IGC), at infinite dilution. In this study, the potential relationships between the microstructure and the surface properties of different cotton fibers are analyzed. This method is based on the analysis of adsorption of gaseous probes on solid surfaces. By measuring the retention time of probes into a column containing the fibers, thermodynamic surface characteristics of these fibers, in particular the dispersive component of their surface energy, and their surface morphological aspects, are determined. The IGC data are correlated with a surface physico-chemical analysis performed by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy.     

Fault Localization at the WDM Layer

A single failure in a communication network may trigger many alarms. When the communication network uses optical fibers as transmission medium and increases its capacity by using Wavelength Division Multiplexing (WDM), the number of alarms and the difficulty to locate the failure are considerably higher. In this case, a single failure may interrupt several channels which causes a large information loss. We propose an Alarm Filtering Algorithm (AFA) for the fault management of an optical network that supports multiple failures and works in the presence of non-alarming elements, that is, network components which may fail but never generate an alarm (e.g. optical fibers). The algorithm provides a list of components whose failure explain the observed alarms. It avoids the use of failure probabilities, which are difficult to estimate, and does not need a global knowledge of the network topology. Moreover it also tolerates alarm losses and false alarms. The algorithm is tailored to the specific behavior of the hardware components of an optical network when a failure occurs. The classification of the network components according to the alarm signals they generate enables a formalization of the alarm-filtering problem and results in an efficient algorithm for localizing the failure(s). This algorithm is applied to the WDM rings of the COBNET network [1] (COBNET is a European ACTS project) and to a meshed optical network with the ARPA2 topology.     

Set based robust design of mechanical systems using the quantifier constraint satisfaction algorithm

Embodiment design is an important phase of the design process where the initial design parameters and their feasible solution spaces with design configurations are decided for the design problem. This article presents a new approach of embodiment design space exploration of the product based on set based design with integration of robustness for the mechanical systems. The approach presented addresses the initial design phase of the mechanical systems design and provides a three step approach based on a formal expression syntax, transformation and evaluation engine and a computational algorithm for performing a domain search for sets of robust solutions for the product designs by taking into the account the variations and uncertainties related to the manufacturing process and material. The approach is based on the design domain exploration and reduction techniques. This is achieved by the utilization and integration of existential and universal quantifiers from the quantifier constraint satisfaction problem (QCSP) for the expression of the parameters and variables related to the product design and robustness. The quantifier notion has been used to develop the consistency check for the existence of a design solution and existence of a robust design solution. In order to compute the developed quantifier approach, an algorithm based on the transformation of the quantifier with interval arithmetic has also been developed. In order to demonstrate the capability of the developed approach, this article includes three examples of mechanical systems from earlier research works that apply the quantifier model and the resolution algorithm to successfully explore the design domain for robust solutions while taking into account different types of variations such as variations in mechanical/material properties, manufacturing variations or variations in geometric dimensions which may be of continuous or discrete type.     

Some links between extremum spanning forests,watersheds and min-cuts

Minimum cuts, extremum spanning forests and watersheds have been used as the basis for powerful image segmentation procedures. In this paper, we present some results about the links which exist between these different approaches. Especially, we show that extremum spanning forests are particular cases of watersheds from arbitrary markers and that min-cuts coincide with extremum spanning forests for some particular weight functions.