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The paper deals with the measurement in continuous industrial furnaces. Measuring technique and measuring device are presented. Temperature evolutions are measured on the experimental billet and records of the furnace heating-control system are shown. Furnace distributions of temperature, heat flux, and heat transfer coefficient are determined by means of the billet heating process computer modeling.

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Active thermography is an infrared-based technique for nondestructive testing of materials. It often uses advanced evaluation techniques based on temperature spatial and temporal changes. Results of active thermography are contrast differences, which indicate possible defects in an inspected material. These differences cannot be quantified by temperature. This contribution is focused on the active thermography results' evaluation parameters and the contrast-to-noise ratio method, which can be used for quantitative evaluation of the results. Different result interpretation procedures are introduced. The influence of a selection method for indication and reference regions and the effect of image scaling on inspection results are discussed.

The hole drilling residual stress measuring method is based on drilling a small hole in a material sample and measuring the strain relieved in the hole vicinity by a special strain gauge rosette. The temperature and thermal strain induced by the drilling process can cause significant errors in the relieved strain measurement. The paper deals with computer simulation of the thermomechanical process in the sample during drilling. The first part is devoted to the evaluation of heat flux from the drilling tool to the drilled material using the sample surface temperature measured by thermography. The second part deals with determination of real strain and strain gauge thermal output (apparent strain) at the strain gauge location during and after drilling. The paper describes the computer modelling technique for solving an indirect thermal problem of drilling heat flux determination and a direct thermomechanical problem for a set of the process alternatives. Comparisons of simulated and experimentally determined temperatures and strains are presented.