SearcharxivSearch

arXiv · 1106.2207

Optimisation de la taille de la série: illustration par un cas industriel de sous-traitance mécanique

Abstract

Reducing costs of manufactured products is one of the key issues of companies. Bar turning companies (mechanical subcontracting companies) are faced with the following dilemma: use a pull strategy or use a push strategy. Instinctively these companies produce more than demand required by customers. This strategy allows them to respond to requests forecasts and reduce their cost of changeover time. These companies make a bet on sales opportunities and think to realize an additional profit. We have tried to find in this study to provide elements to know the limits of this strategy. Our proposal focuses on developing a model to support the decision taking into account the mix of opportunities, economic constraints and mean constraints. This model features the particular importance of high rates of ownership and the risk of not selling. Réduire les coûts de revient des produits fabriqués est une des problématiques essentielles des entreprises d'aujourd'hui. Les entreprises de décolletage (entreprises de sous-traitance mécanique) sont confrontées au dilemme suivant : produire juste la demande client ou produire plus. Instinctivement ces entreprises, dont les temps de changement de série sont élevés, cherchent à produire plus que la demande exigée par le client. Cette stratégie leur permet de répondre à des demandes prévisionnelles et réduire ainsi le coût de revient des produits. Ces entreprises réalisent un pari sur les opportunités de vente et pensent réaliser un gain supplémentaire en réalisant des stocks. Nous avons cherché dans cette étude à fournir des éléments de décision pour connaître les limites de cette règle de gestion. Notre proposition porte sur le développement d'un modèle d'aide à la décision prenant en considération le mixte entre opportunités commerciales, contraintes économiques et contraintes de moyen. Ce modèle souligne l'importance particulière du taux de possession et du risque de non vente.

Explore related subjects

Keep this discovery

BibTeXRIS

Barbara Lyonnet, Maurice Pillet, Magali Pralus. 2011-06-11. Optimisation de la taille de la série: illustration par un cas industriel de sous-traitance mécanique. https://arxiv.org/abs/1106.2207

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Circular Economy Synergies and Trade-offs in Data Centres

This report analyses data centre (DC) sustainability and circularity, revealing existing synergies and trade-offs: The PUE is too coarse, mixing cooling and power provisioning. It wrongly attributes server fan consumption and transformation losses to IT energy. It does not measure compute but infrastructure efficiency, which is already outstanding. Compute energy, however, is exploding. Better energy metrics for DCs would thus cover i) compute efficiency, ii) transformation efficiency, and iii) cooling overhead. Trade-offs exist between cooling energy and water as well as on-site and upstream water: Consuming water on-site lowers the cooling energy, which also lowers the water consumed upstream in power generation. For 'wet' electricity, there is little competition: It is worth spending more on-site energy to save both electricity and related upstream water. For 'dry' electricity, there is a trade-off. Waste heat recovery brings energy circularity but has limited uses and is not the same energy quality, a fact not reflected by current metrics. A better metric would consider the avoided energy through heat recovery instead of the amount recovered. Material circularity can be achieved by interpreting the 9R framework in the context of DCs. Circularity-enhancing measures can be categorised into product design, process design and business models, choice of materials, and operating conditions. Together, they have effects across all circularity levels. The relation between DCs and the power grid is complex. Modern DCs present new challenges for the grid. Mitigation includes battery storage and onsite generation. These measures have, in turn, further consequences, both beneficial and detrimental. They can offer grid flexibility as well as innovations in the field of energy. But they also bring noise, pollution, and GHGs, and compete with the energy sector for resources.

cs.OH

Digital Twin Modeling of a Highly Automated Agricultural Tractor

In efforts to increase research efficiency and availability, a digital twin of our research tractor (AMX G-trac) is created, focusing especially on the CAN communication for data reading and actuation command following the ISOBUS protocol. Mevea Simulation Software is utilized as the foundation, providing the kinematic model and visuals, while Python is used to read and write CAN messages over a Kvaser CanKing virtual CAN channel. Various performance tests involving straight line and turning behavior are performed in both the digital twin simulation and in the real world to measure similarity. Results indicate that the Mevea model behaves very comparable in its lateral dynamics, often within 5-10 percent, but requires better data to fully capture the longitudinal aspects like acceleration. The final model described in this paper sets the table for a second iteration to include more tractor functions such as hydraulics and tractor-implement dynamics.

cs.OH

Risk-based Design for Sustainability in Cloud Systems: Insights from an Experts' Survey

Cloud Systems' Sustainability is critical in Cloud Computing, especially with the growing demand in many industries. Sustainability risks in Cloud Computing can be tricky, mostly because of system complexity and their impact on performance. Thus, this research focuses on Risk-based design (RBD) and how it can support the early identification of possible risks for Cloud System Sustainability, as well as respective mitigation strategies of each risk. In order to successfully identify risks of Cloud System Sustainability, an Expert Survey is conducted including experts with different roles from different industries, to identify possible sustainability risks of a Cloud System on all different levels. Thematic analysis of the responses resulted in a categorization of risks, as well as in the identification of mitigation strategies and factors affecting each risk. Such findings can be helpful for researchers and practitioners that utilize RBD when building sustainable Cloud systems.

cs.OH