To get ready for the hard international competition, firms have to convince themselves of the pressing necessity of optimizing its competitiveness factors. In this perspective, this article proposes a general model of management system of firms through the implementation of tools of Lean Manufacturing. This method establishes an approach to introduce an action plan to improve the performance of a firm. Knowing that the Algerian firms do not escape the constraints of competitiveness, the adopted model is applied to two strategic firms of the Algerian industry and the final result gives a series of measures to improve their competitiveness and their performances, simultaneously.

In an unstable context characterized by the turbulence of markets and the competitive pressures, the firm is forced to adopt a strategy of development to rema in co mpetitive. The me mbe rship of Algeria to several global organizations imposes on the Algerian company a need for particular adaptation. New challenges await the Algerian firm, changes generated by the liberation of exchange and world co mpetition. To improve its co mpetitiveness to prepare for international competition, this article proposes an adaptation of the management system of the A lgerian firm through a Lean Manufacturing tool, the 5S method. The 5S tool improves productivity because it is designed to check the manufacturing process and ensure that dysfunctions are identified and dealt. The validation of the 5S method was tried on essential equipment in the gas Algerian co mpany. Every "S" is applied to every dysfunction of this equip ment found fro m the Ishikawa diagram and the results are proposed solutions or actions that will allow an imp rovement of the production process by elimination of the wasting and therefore improve the competit iveness of this company.

A reverse supply chain is viewed as a process from consumption point to recovery point and the management of domestic waste is considered as a specific and complex reverse supply chain. This important sector represents a high challenging problem for our cities, constrained by financial, social, health and environmental considerations. This paper proposes multicriteria decision aid to help choose an efficient domestic waste management strategy. In fact, Multicriteria decision making techniques are considered as a key option to solve this type of problems, giving a solution that represents a good compromise between different preferences. The adopted approach consists in outranking a set of candidate management plans using a method based on partial aggregation criteria. This model is applied on a real case study of an Algerian city and to validate the obtained results, a deep sensitivity analysis is carried out, giving the most appropriate plans.Growing Science Ltd. All rights reserved. 7

At the time of the new information technologies, computer networks are inescapable in any large organization, where they are organized so as to form powerful internal means of communication. In a context of dependability, the reliability parameter proves to be fundamental to evaluate the performances of such systems. In this paper, we study the reliability evaluation of a real computer network, through three reliability models. The computer network considered (set of PCs and server interconnected) is localized in a company established in the west of Algeria and dedicated to the production of ammonia and fertilizers. The result permits to compare between the three models to determine the most appropriate reliability model to the studied network, and thus, contribute to improving the quality of the network. In order to anticipate system failures as well as improve the reliability and availability of the latter, we must put in place a policy of adequate and effective maintenance based on a new model of the most common competing risks in maintenance, Alert-Delay model. At the end, dependability measures such as MTBF and reliability are calculated to assess the effectiveness of maintenance strategies and thus, validate the alert delay model.

Ce travail s'inscrit dans le cadre de l'implantation de la maintenance basée sur la fiabilité (MBF) dans un complexe gazier situé en Algérie. L'objectif ciblé de l'étude est de classer les équipements de production selon leur degré de criticité par rapport à certains critères déterminés. Pour ce faire, nous proposons d'appliquer deux méthodes centrées sur le concept d'agrégation multicritères et de comparer les résultats afin d'obtenir un classement des équipements critiques. La hiérarchisation des équipements ainsi obtenue permettra de définir les actions prioritaires de maintenance.This work is part of the implementation of reliability-based maintenance (RCM) in a gas complex located in Algeria. The objective targeted of the study is to classify the production equipment according to their degree of criticality with respect to certain criteria. To do this, we propose to apply two methods centred on the concept of multi-criteria aggregation and compare the results to obtain a classification of critical equipment. Prioritization of the equipment so obtained will identify priority actions for maintenance.