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The focus of this paper is customer order scheduling (COS) problem, where each order consists of a set of jobs that must be shipped as one batch at the same time. In COS each job is part of a customer order and the make-up of the jobs in the order are pre-specified. Most of the existing research deals with COS in a single machine or in a parallel machine shop for developing an optimal solution. COS is common in a normal job shop, and the more complex the shop, the more complex the scheduling. Most existing research has focused on trying to reduce the completion time of the batch. That is, the focus is only on the point in time the last job is finished, while ignoring the actual duration of the jobs within the same order. The longer it takes to complete all the jobs within an order the more it increases the stock of finished goods and the more it deteriorates the efficiency of the logistics and the supply chain management. A new dispatching rule, referred to as Minimum Flow Time Variation (MFV), has been proposed for COS in a normal job shop, in order to reduce the total time it takes to complete all jobs within the same order. That is, the individual completion times of all jobs for the same customer order will be controlled in order to improve the shipping performance. In the simulation test and statistical analysis, the level of work in process (WIP) under the MFV rule in the finished goods warehouse is reduced by more than 70% compared to any other method. The MFV method will efficiently reduce the stock level of finished goods, and controls the waiting time required before they can be shipped. Depending on the environmental factors, the performance of our proposed method will become increasingly significant the more complex the system.

This paper deals with a load-balancing problem among several operators in a semi-automatic parallel machine shop in which two types of machine are operated. The objective is to assign jobs to the proper machines and allocate machines to operators in order to minimize the unbalance of the workloads among operators under the constraints of available machine- and operator-time. There are two types of parallel machines and jobs are classified into the two types. However, operator can handle machines of both types.Although, this situation can be formulated with non-linear integer programming, it is difficult to solve this program. Therefore, a hierarchical heuristic solution procedure is suggested and the performance of the algorithm is evaluated with various data.

A conceptual framework for flexible manufacturing called flexible automation architecture (FAA), in a computer integrated manufacturing (CIM) environment is proposed. The framework is based on the three-level database architecture for designing database systems. FAA partitions the manufacturing environment into database analogous logical levels of product requirements (external view), logical shops (conceptual view) and machine shops (internal view). The flexibility in FAA is achieved not by the traditional structuring of machines on the shop floor, but rather through a series of logical processes in the logical shop level. Each logical process is a generic (abstracted) process catering to multiple product processes at the product requirements level, and manufactured by a stable group of machines at the machine shop level. The framework is illustrated with a manufacturing case and a discussion of information system support in the form of expert systems.

Two sets of programs for analyzing machine shop operations have been developed for application by a programmable calculator. The first set generates time standards for a wide variety of metal cutting and grinding operations: the second per performs an analysis of the costs of labor, machinery, and tooling.Thiis latter analysis also produces the optimum machine speed to employ to minimize production time or cost, or to maximize profit.

An automated system based on Symphony spreadsheet software has been developed to monitor machine tool utilization and capacity in a small- to medium-sized machine shop. This application compiles reports on annual machine tool requirements and use from production routing data for a shop producing over 100 different small machined parts with batch sizes ranging from 100 to 1000 parts and up to 25,000 parts per year. The operational routings for approximately 30 parts are currently stored in the system. Levels of utilization are analyzed, which aids in determining the need for addition equipment or multiple workshifts, and thereby helps balance the workload and product flow. Valuable information was compiled in a special report for layout of a new shop facility. Group technology cell arrangements of equipment were analyzed for capacity and utilization. Many Symphony spreadsheet and data base management features were used to produce this program. The final system incorporated menu systems for users unfamiliar with this spreadsheet software.