Production/maintenance cooperative scheduling using multi-agents and fuzzy logic

Within companies, production is directly concerned with the manufacturing schedule, but other services like sales, maintenance, purchasing or workforce management should also have an influence on this schedule. These services often have together a hierarchical relationship, i.e. the leading function (most of the time sales or production) generates constraints defining the framework within which the other functions have to satisfy their own objectives. We show how the multi-agent paradigm, often used in scheduling for its ability to distribute decision-making, can also provide a framework for making several functions cooperate in the schedule performance. Production and maintenance have been chosen as an example: having common resources (the machines), their activities are actually often conflicting. We show how to use a fuzzy logic in order to model the temporal degrees of freedom of the two functions, and show that this approach may allow one to obtain a schedule that provides a better compromise between the satisfaction of the respective objectives of the two functions

Parameters of Carcass Cuts and Measurements of Martinik Lambs Managed under Intensive Conditions

The Martinik sheep is selected for its good adaptive and reproductive traits. The production sector reproaches it with low carcass conformation, although its carcasses have been little described. Two intensive fattening experiments were conducted, whereby lambs were slaughtered for linear measurements and cuts. The variables were analyzed and allometric equations were determined. The database (n = 43) was adjusted for feeding levels and slaughter weight groups (SW: 28, 32 and 36 kg). Mean cold carcass (CC) weights varied (P 0.05). The weights of all carcass cuts significantly (P < 0.01) increased with CC increase. Shoulders and legs represented 18 and 34% of CC, respectively. Various measurements taken on the carcass and pelvis width significantly increased (P < 0.05) with CC increase (near 9% difference between extreme weights). Indices of carcass and leg compactness (0.32 and 0.45, respectively) did not vary with SW, whereas weight indices did. Allometric coefficients of the shoulder (0.915) and leg (0.891) were in line with those of the literature. This preliminary description of Martinik sheep carcasses could be made available to the sector actors in order to pursue the work and help to better select breeds and management systems