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In road accidents involving pedestrians, the speed of a vehicle is determined from the distance covered by the thrown body. The distance under consideration includes both flight and sliding and is known as a throw length. This paper describes an attempt to develop an improved model of a sliding phase. The pedestrian is treated as a moving mass supported by a spring and a dashpot. The friction present between the body and the ground depends on the sliding velocity of the mass. The use of the spring and non-linear dashpot allows for better modeling of the force between the body and the ground, and more accurate computation of the length of the sliding phase. The developed model and a procedure for computing the length of the airborne trajectory were incorporated in a computer program to predict the throw distances for simulated accidents. The results of computations for a new model are in good agreement with the data obtained from the real accidents.

The objective of the research described in this paper was to develop a reliable method to evaluate the residual stress existing in an axisymmetric body from measurements of the post-grinding deformation. The developed method is based on finite element analysis and utilizes the concept of influence coefficients. What makes the method attractive is that it does not require fine division of the body into finite elements, and that it utilizes rather limited information on the post-grinding deformation. For example, quite accurate results can be obtained from measuring changes in diameter for five different cross sections of a cylinder. The developed method was tested by Monte Carlo simulation. The residual stress, the post-grinding deformation and the measurements were all generated and simulated by a computer. The paper provides a detailed description of the method and lists practical hints on how to avoid pitfalls in developing similar procedures.