Much of the reason for this can be attributed to the hesitation of companies to pay large sums to invest in software which, at the least, requires skills to operate beyond those likely to be found within company resources, and over which there is bound to be doubt as to whether the investment can be recouped. While price is not the only issue of concern, it is undoubtedly an important factor which must be addressed if knowledge is to be spread and momentum created in this sphere. A modelling scenario It takes appreciable time to observe and understand by questioning and discussion the workings of any large company. In the present case, the company's products are highly perishable, and a significant part of the core operation consists of the movements of a variety of vehicles performing different functions with intensities varying on both a daily and a weekly cycle. For simulation purposes, an essential step following the initial observation period was to abstract a skeletal process description such as the following which served as the basis for subsequent modelling and experimentation.
Milk is delivered to the dairy each day by two different methods.
The first method is by the company's own tankers who collect milk from farms with which the company has a supply contract. This amount fluctuates broadly with the time of year, but very little on a day by day basis. The second source is by deliveries from an external company, the nature of which are determined by a monthly contract. In addition, the dairy acts as a buffer, sometimes calling for milk from other dairies, and at other times sending them excess milk. Tankers arriving at the yard are allowed to enter only if there is parking space available in the yard, which can accommodate a maximum of 18 tankers.