103 research outputs found
Biomass as a helpful support to sun and wind for insulated small electrical networks
International audienceThe aims of CIEM is to respond to challenges in the rapidly developing fields of Power Engineering and Environmental Engineering, and to inspire both research studies and practical applications by promoting interaction among scientists from universities, research institutions, and industry
Progress in large-shared projects : method for forecasting and optimizing project duration in a distributed project
In large-shared projects, it is still difficult to measure progress due to the complexities involved, because the realization is shared among departments of a company or among companies in the world. Project management and operations research literature is reviewed for discovering various techniques applicable. Widely used tools for progress measurement and forecasting, such as Earned Value Analysis, Progress Plot, Milestone and Resource slip charts, concurrent engineering, can be employed. This paper is based on a problem of pharmaceutical industry where the effectiveness of a certain medical treatment is examined on patients in a number of countries. The number of variables involved increase the complexity of this problem. The main objective is to analyze the effectiveness of a solution in different situations during the project such that a better project duration and a lower cost can be achieved. Our findings suggest that reallocation of patients among countries produces better results in terms of progress
A greedy heuristic approach for the project scheduling with labour allocation problem
Responding to the growing need of generating a robust project scheduling, in this article we present a greedy algorithm to generate the project baseline schedule. The robustness achieved by integrating two dimensions of the human resources flexibilities. The first is the operatorsâ polyvalence, i.e. each operator has one or more secondary skill(s) beside his principal one, his mastering level being characterized by a factor we call âefficiencyâ. The second refers to the working time modulation, i.e. the workers have a flexible time-table that may vary on a daily or weekly basis respecting annualized working strategy. Moreover, the activity processing time is a non-increasing function of the number of workforce allocated to create it, also of their heterogynous working efficiencies. This modelling approach has led to a nonlinear optimization model with mixed variables. We present: the problem under study, the greedy algorithm used to solve it, and then results in comparison with those of the genetic algorithms
Flexible resources allocation techniques: characteristics and modelling
At the interface between engineering, economics, social sciences and humanities, industrial engineering aims to provide answers to various sectors of business problems. One of these problems is the adjustment between the workload needed by the work to be realised and the availability of the company resources. The objective of this work is to help to find a methodology for the allocation of flexible human resources in industrial activities planning and scheduling. This model takes into account two levers of flexibility, one related to the working time modulation, and the other to the varieties of tasks that can be performed by a given resource (multiâskilled actor). On the one hand, multiâskilled actors will help to guide the various choices of the allocation to appreciate the impact of these choices on the tasks durations. On the other hand, the working time modulation that allows actors to have a work planning varying according to the workload which the company has to face
Decision-based genetic algorithms for solving multi-period project scheduling with dynamically experienced workforce
The importance of the flexibility of resources increased rapidly with the turbulent changes in the industrial context, to meet the customersâ requirements. Among all resources, the most important and considered as the hardest to manage are human resources, in reasons of availability and/or conventions. In this article, we present an approach to solve project scheduling with multi-period human resources allocation taking into account two flexibility levers. The first is the annual hours and working time regulation, and the second is the actorsâ multi-skills. The productivity of each operator was considered as dynamic, developing or degrading depending on the prior allocation decisions. The solving approach mainly uses decision-based genetic algorithms, in which, chromosomes donât represent directly the problem solution; they simply present three decisions: tasksâ priorities for execution, actorsâ priorities for carrying out these tasks, and finally the priority of working time strategy that can be considered during the specified working period. Also the principle of critical skill was taken into account. Based on these decisions and during a serial scheduling generating scheme, one can in a sequential manner introduce the project scheduling and the corresponding workforce allocations
Un modĂšle Ă Ă©vĂšnements pour Ă©tudier la flexibilitĂ© opĂ©rationnelle dâun flow shop flexible
La gestion des ateliers de production recherche le meilleur compromis entre les impĂ©ratifs commerciaux, financiers et industriels. Lâobjectif de cet article est la caractĂ©risation et la modĂ©lisation des leviers de flexibilitĂ© dâun atelier de production Ă cheminement unique (« flow shop »), afin dâassurer la flexibilitĂ© opĂ©rationnelle du systĂšme. Cette flexibilitĂ© porte sur le fait que chaque poste de la chaĂźne de production dipose dâune ou plusieurs machines identiques, sur des durĂ©es opĂ©ratoires variables Ă chaque poste selon le nombre des opĂ©rateurs affectĂ©s, et sur les dates de livraison des produits. La convergence entre les ressources requises pour lâexĂ©cution dâun plan de production et celles mises en Ćuvre pour sa rĂ©alisation est favorisĂ©e. La fonction objectif intĂšgre lâĂ©valuation des stocks et en-cours, le coĂ»t du travail et de lâinactivitĂ©, et les consĂ©quences des perturbations. Le problĂšme est rĂ©solu en traitant lâensemble des variables simultanĂ©ment, selon une formulation de programmation mathĂ©matique non-linĂ©aire en variables mixtes (MINLP)
Scheduling of heat integrated multipurpose batch Processes
A systematic mathematical framework for scheduling the operation of multipurpose batch plants involving heat-integrated unit operations is presented. The approach advocated takes direct account of the trade-offs between maximal exploitation of heat-integration and others scheduling objectives and constraints. In this paper, heat transfer takes place directly between the fluids undergoing processing in the heat integrated unit operations, and therefore a degree of time overlap of these operations must be ensured. The modelling is based on the ERTN formalism and a discrete time MILP formulation
Chapitre 3.1 : DĂ©coupage d'un projet et organigramme des tĂąches
Avant d'aborder la méthodologie à employer dans un découpage des tùches d'un projet, il convient de bien cerner la notion de management de projet dont le découpage en constitue un support indispensable. Selon la définition de l'AFNOR, il faut appréhender simultanément deux fonctions distinctes dans le management de projet : d'une part la direction, conduite ou pilotage du projet, et, d'autre part la gestion du proje
Chapitre 3.6 : Ingenierie simultanée
La gestion de projets est souvent perçue, en premiĂšre approximation, comme l'outil pouvant garantir la meilleure maĂźtrise du temps - assez justement d'ailleurs, puisque c'est essentiellement lĂ sa raison d'ĂȘtre. On peut cependant lui trouver quelques lacunes, justifiant l'Ă©tude de mĂ©thodes plus performantes
Biomass as a helpful support to sun and wind for insulated small electrical networks
The aims of CIEM is to respond to challenges in the rapidly developing fields of Power Engineering and Environmental Engineering, and to inspire both research studies and practical applications by promoting interaction among scientists from universities, research institutions, and industry
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