The friction coefficient in the simulation of stamping processes should be defined. Modern simulation software allows its definition as constant or its dependence on pressure or temperature. It is also useful in stamping processes to define different values in different regions, as it often reflects the nature of deformation process. This article deals with the regression and analytical models commonly used to determine the friction coefficients in specified areas of the stamping process. Analytical models were verified by an experimental strip drawing test under the same contact conditions. Steel sheets for the automotive industry were used in experiments and simulations—extra deep drawing quality DC 05 and austenitic stainless steel AISI 304. Friction coefficients were also evaluated when the cup test was performed. A regression model of drawing to the blankholding force was applied to the results. Conformity of friction coefficients when measured by cup tests and strip tests was confirmed. The values of the friction coefficient reached from the experiment were applied in FEM simulation software.

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Economic impact studies are used widely either to secure financial support for an event or to promote an organization or an event. The very nature of impact studies tends to lead to an overestimation of the impact. Discussed in this article are such issues as: types of economic impact, ticketed events versus open-gate events, short-term events such as festivals versus long-term attractions such as parks and museums, offsetting impact within the jurisdiction, treatment of nonwage expenditures, appropriate use of multipliers, especially in short-term or one-time events, and daily expenditures per visitor based on survey of visitors to two festivals in Alabama and Mississippi. The main conclusion is that public sector subsidy to short-term events should be based more on their role in enhancing the area's quality of life than on their estimated economic impact.

Non-collision trajectories of an industrial robot are the key objective when planning its handling cycles. When the robot should move optimally, precisely and safely in each situation, it is necessary that every obstacle placed in its transition trajectory should be programmed and avoided. The optimal trajectory corresponds to choosing, if possible, the shortest and most appropriate way for the specific movement to be finished. The task of avoiding obstacles by the industrial robot in its working zone can be solved by various methods and algorithms. The paper shows the use of the kinematics SCARA as a way of avoiding obstacles by a robot in the working zone using the Lee algorithm. The configuration fields and networks are being modelled for the avoidance of obstacles together with their evaluation and the search for the shortest trajectory reflected in the robot programming.