A new need for safety stocks in a supply chain dedicated to customized mass production.

In a supply chain designed for the production of goods of wide variety, the production schedule creates an ordered list of all the alternate components that will be mounted on a same post of the chain. The supply of these components by the supplier may induce transportation-related constraints. There from systematically follows a time-gap between orders and deliveries. This mechanism, commonly called “rank-change”, may be analyzed with the help of the multinomial distribution associated to these alternate components; only a simulation approach has relevance as of that matter, for an analytic approach is not possible. Such an analysis allows assessing the importance of the need to form safety stocks because of the lot sizing, even though requirements are certain.stock de sécurité; lotissement dans transport; chaîne logistique;

Synchronization and decoupling of plants piloting in a supply chain dedicated to customized mass production.

The synchronization of the production of a manufacturing supplier, who makes alternate components assembled on his industrial customer’s work station with this client’s production specialized in mass production of highly diversified products, must take into account the improvement of their knowledge of the final demand (displacement of the Order Penetration Point) and the distance of some of the suppliers. The customer periodically forwards firm orders to his supplier calculated so as to preclude any production line stoppage. It is necessary that the supplier honor them to ensure the decoupling of the control of these two entities in the supply chain and define the efficiency of synchronization. In the considered context, the supplier also receives all available projected information from the industrial customer (final orders, firm on the short term, and structural characteristics of the final demand beyond). The efficiency of the supplier depends on the proper use of all information, notably when the production cycle of alternate components is longer than the demand cycle. In the study of the customer’s requirements, it is necessary to take into account the batch constraints linked to transportation, which compels the customer to hold safety stocks even though the set up organization guarantees that orders will be duly honored. The determinants of these stocks will be put in evidence. Similarly at the supplier, safety stocks will be necessary if the production process involves grouping in batches.synchronisation de la production dans une chaîne logistique; stock de sécurité; chaîne logistique;

The causes and determination of safety stocks in upstream supply chains for mass production of customized products

In an upstream supply chain dedicated to the mass production of customized products, many sources create production instability: the level and structure of production in the final assembly line, variability of lead times, quality issues, packaging and loading constraints on transportation, demand anticipation, and the synchronization of the flows of components sent, received, and produced. For periodic replenishment systems, each member of the supply chain must have two different safety stocks to prevent some sources of fluctuations: a safety stock of produced components to meet the demand of downstream links and a safety stock of supplied components to ensure its own production. Procedures must take the organizational framework of information and products exchanges into account. The relevance of supply and production rules depends on the relevance of structural information broadcast along the supply chain

Information to share in supply chains dedicated to the mass production of customized products for decentralized management

In an upstream supply chain dedicated to the mass production of customized products, decentralized management can be an efficient and effective method in a steady state in which stochastic characteristics of customers' demands remain stable. However, this is possible only if all echelons that precede the final assembly line use periodic replenishment policies that restrain the stockout risk to a low predetermined probability. The safety stocks' levels are more difficult to define for alternative or optional parts, as well as the components they use, whose demands are weighted sums of random variables, affected by several random factors and organizational constraints. The factors and constraints to consider are not the same for supplied and produced components. The random demand of a component depends on the demand of alternative or optional parts mounted in the final product, through a double transformation involving the bill of materials explosion, which is at the origin of the weighted sum of random variables, and time lags. In the steady state, the knowledge of the probability distribution of that random variable allows for the determination of safety stocks that decouple the management of upstream supply chains. Progressive changes in the steady state require periodic and progressive adaptations of the safety stocks that do not directly depend on the final demand knowledge

The information to share in upstream supply chains dedicated to mass production of customized products for allowing a decentralized management

In an upstream supply chain (USC) dedicated to the mass production of customized products, decentralized management is possible and performing in the steady state, if all the links that precede the final assembly line use periodic replenishment policies. These policies require appropriate safety stocks of alternative or optional components. To achieve such performance in the real world, the supply chain must identify the source of any changes. Unexpected fluctuations in the production of USC plants suggest a bullwhip effect, yet most studies of the bullwhip effect fail to consider build-to-order supply chains. A double transformation of available information, derived from bill of materials explosions and time lags, is required to restore steady-state performance. It then remains to detect and quantify changes and, if a build-to-order strategy of alternative components is possible, use decision rules that are robust to such changes

Synchronization and decoupling of plants piloting in a supply chain dedicated to customized mass production

The synchronization of the production of a manufacturing supplier, who makes alternate components assembled on his industrial customer’s work station with this client’s production specialized in mass production of highly diversified products, must take into account the improvement of their knowledge of the final demand (displacement of the Order Penetration Point) and the distance of some of the suppliers. The customer periodically forwards firm orders to his supplier calculated so as to preclude any production line stoppage. It is necessary that the supplier honor them to ensure the decoupling of the control of these two entities in the supply chain and define the efficiency of synchronization. In the considered context, the supplier also receives all available projected information from the industrial customer (final orders, firm on the short term, and structural characteristics of the final demand beyond). The efficiency of the supplier depends on the proper use of all information, notably when the production cycle of alternate components is longer than the demand cycle. In the study of the customer’s requirements, it is necessary to take into account the batch constraints linked to transportation, which compels the customer to hold safety stocks even though the set up organization guarantees that orders will be duly honored. The determinants of these stocks will be put in evidence. Similarly at the supplier, safety stocks will be necessary if the production process involves grouping in batches.ou

Stocks de sécurité de chaîne logistique – amont

International audienc

Détermination des stocks de sécurité dans une chaîne logistique-amont dédiée à une production de masse de produits fortement diversifiés

In an upstream supply chain dedicated to the mass production of customized products, many sources of production instability can be identified: the level and structure of the production of the final assembly line, the variability of lead times, the quality issues, packaging and loading constraints in transport, the anticipation of the demand, the synchronization of the flows of the components sent, received and produced. In the case of periodic replenishment policies, two different safety stocks are needed for every plant of the supply chain, which prevent from these various sources of fluctuations: a safety stock of produced components to face up to the demand of its downstream links and a safety stock of supplied components to face up to its production. The mobilized procedures must take into account the organizational framework of the exchanges of information and products. The relevance of the supply and production rules is based on the relevance of structural information broadcast along the supply chain

Analyse des déterminants à court terme de la capacité d’une unité de production

International audienc

Stocks de sécurité de chaîne logistique – amont

International audienc