The basic theory of the Petri net model is introduced and the characteristics of alternative process planning are analyzed. Then, the modeling of alternative process planning based on Petri nets is discussed in detail...The basic theory of the Petri net model is introduced and the characteristics of alternative process planning are analyzed. Then, the modeling of alternative process planning based on Petri nets is discussed in detail. Themodeling process is partitioned into three stages:the modeling of feature operation chains and grouped feature operation chains, the modeling of a feature group's setup determination and the modeling of part setups and related machine function. This paper focuses on the first and the third stages. Furthermore, a case study and implementation of system are described.展开更多
Production planning under flexible job shop environment is studied.A mathematic model is formulated to help improve alternative process production.This model,in which genetic algorithm is used,is expected to result in...Production planning under flexible job shop environment is studied.A mathematic model is formulated to help improve alternative process production.This model,in which genetic algorithm is used,is expected to result in better production planning,hence towards the aim of minimizing production cost under the constraints of delivery time and other scheduling conditions.By means of this algorithm,all planning schemes which could meet all requirements of the constraints within the whole solution space are exhaustively searched so as to find the optimal one.Also,a case study is given in the end to support and validate this model.Our results show that genetic algorithm is capable of locating feasible process routes to reduce production cost for certain tasks.展开更多
Tourism Environmental Carrying Capacity Planning (TECCP)is a regulated part of the Geopark General Planning in China.But,because the exact numerical carrying capacities are difficult to confirm and the effects of tour...Tourism Environmental Carrying Capacity Planning (TECCP)is a regulated part of the Geopark General Planning in China.But,because the exact numerical carrying capacities are difficult to confirm and the effects of tourism can take many forms,some of which are only loosely related to amount of users, the efforts of estimating of the maximum amount of tourists would mislead the manager and operator展开更多
文摘The basic theory of the Petri net model is introduced and the characteristics of alternative process planning are analyzed. Then, the modeling of alternative process planning based on Petri nets is discussed in detail. Themodeling process is partitioned into three stages:the modeling of feature operation chains and grouped feature operation chains, the modeling of a feature group's setup determination and the modeling of part setups and related machine function. This paper focuses on the first and the third stages. Furthermore, a case study and implementation of system are described.
基金Sponsored by Key Subject Foundation of Beijing Municipal(XK100070530)
文摘Production planning under flexible job shop environment is studied.A mathematic model is formulated to help improve alternative process production.This model,in which genetic algorithm is used,is expected to result in better production planning,hence towards the aim of minimizing production cost under the constraints of delivery time and other scheduling conditions.By means of this algorithm,all planning schemes which could meet all requirements of the constraints within the whole solution space are exhaustively searched so as to find the optimal one.Also,a case study is given in the end to support and validate this model.Our results show that genetic algorithm is capable of locating feasible process routes to reduce production cost for certain tasks.
文摘Tourism Environmental Carrying Capacity Planning (TECCP)is a regulated part of the Geopark General Planning in China.But,because the exact numerical carrying capacities are difficult to confirm and the effects of tourism can take many forms,some of which are only loosely related to amount of users, the efforts of estimating of the maximum amount of tourists would mislead the manager and operator