WAITING FOR PRACTICALITY provides insight into the practical use of seldom-used theories, and for this purpose utilizes the queuing theory. The queuing theory involves “the use of mathematical models, theorems and algorithms in the analysis of systems in which some service is to be performed under conditions of randomly varying demand, and where waiting lines or queues form due to lack of control over either the demand for service or the amount of service required or both. Since the queuing theory has applications in the areas of process, operation and work-study it is relevant to the course study.
Students were required to find out the existing line efficiency in a production unit and recommend methods to improve the existing line efficiency. For this purpose, the students needed to collect the data of how long the production lines stopped running and the lines remained down.
This was made simple as the machine controller automatically provided this data. The data collected by the students showed that there was a line efficiency rate of fifty-seven percent, a stoppage rate of two stops per hour, and an average throughput of 3,050 parts per day.
Using this data and their observation of the working system of the production line, they sat down to formulate a solution. One of the main reasons for the downtime of the production line was that the operator was involved in the packing too and as such found it difficult to in the middle of the process to remove the hindrance and get the machine running again.
The students hit upon a plan of job re-allocation of job function as a solution for the line efficiency problem. For every three production lines, one worker was assigned the function of keeping the machines running. This function included performing the set-ups, unjam the machines, and replenish materials. The other two workers would take on the inspection and packing of the three production lines. The solution was worked out by the students solely on a practical basis without the use of any theoretical frameworks.
The tutor of the students decided to apply a theoretical framework in the form of the queuing theory to assess how far this solution would go in solving the problem. Using the framework of the queuing theory the tutor found that by increasing the service rates through the suggestions of the students there was every possibility of increased efficiency of the production lines and hope for an improved efficiency in the range of twenty to thirty percent.
Efficiency rates went up and the management impressed by the solution gradually increased the packers from two to three and then from three to four per line and finally came out with a lone of efficiency that had improved by eighty-four percent without any investment on machinery.
WAITING FOR PRACTICALITY goes to show that solutions may be arrived at by practical solutions of the observed data, but an application of the theoretical frameworks provide an understanding of the extent to which the arrived at a solution will work in a given circumstance.
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