## 4 Discussion
However, after presenting all input data, we found cases there were activities in production that were not defined by the valid documentation or were ambiguously quantified from the point of view of the number/duration. The subsequent analyses of the capacity utilisation of the employees by the activities defined by the valid regulations and activities without any valid regulation proved there was a 5-15% increase in the total capacity of the staff. From the process point of view, these activities were inevitable for maintaining the quality of the final product defined by the customer; however, they were missing not only in the valid documentation of the company regulations but also in calculations of the costs for production. During the manufacturing process, the company generated--in this way--a constant loss of the production staff because the real production costs were higher than the planned ones. In this case, the potential of the designed methodology was transparent in supporting the aggregate planning and calculating the costs. * What is the further direction of the research in this area? * We would like to continue this research area and enrich the module supporting the planning procedure by further functions and calculations. We gathered a basis of data and we want to continue evaluating the parameters of the production system from the mathematical point of view, e.g., Process Lead Time (PLT) for detecting the inventories, Value-added Activities (VA) and the Process Cycle Efficiency (according to the Little's Principle) for the overall assessment of the designed system's effectiveness. The creation of the algorithms for defining the optimal WIP and connecting the module supporting the production capacity planning on IoT will be a very important part of our research. The created interconnection will enable utilising the data from the shift card or the engineering devices. Based on the saved data of a particular shift card and the engineering device the system will calculate the real OEE. This function will help us acquire more accurate data necessary for creating a production plan and calculating the capacity of the engineering devices. * What is the usability of the methodology in practice? * The methodology described in the article requires its application to meet several prerequisites. Strictly defined position--Working positions that will be designed must be defined from the point of view of workplaces. Strictly defined working activities--to balance the workload and utilisation, it is necessary to have defined activities their range and duration. Strictly defined limiting conditions--for the correct design of the production process and its workload, knowledge of the spatial limitations (for example, wall size, dimensions of the hall) and time constraints (for example, calendar, worker time fonds, shift duration) is required. For the above reasons, the methodology is designed for discrete production with sufficient seriality and repeatability. The proposed model gives engineers in practice a powerful tool for variant modelling and simulation of production processes in order to optimally utilisation human capacities.