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The paper presented a multipurpose system for testing of dental prostheses within the static and kinematic conditions as well as the conditions of its stability quick analysis. The common goal of prosthetics specialists is to define biomechanical criteria shaping the restorations to protect the existing state of the biological substrate [1]. In prosthesis biomechanics, the gingival soft tissue, as substances with heterogeneous properties, are difficult to individual assessment of the value, direction and duration of the occlusion forces transmitted by the prosthesis in the life cycle [2]. More predictable are static or kinematic behaviors, reflecting the mechanical states of prosthesis design with designed shape and material properties which are possible to determine. However, static measurements of dentures do not reflect their work in natural conditions [3], and can only designate the values of selected parameters (deflection, stress) during the reference of constant load values. The article presents the author's research stand for kinematic loads testing, which are similar to natural ones during shredding of food. The results of stress and strain of denture prosthesis, identified during laboratory tests, will be used to verify the mathematical models of dentures during kinematic forces.

This article investigates the issue of measuring high-power microwave (HPM) pulses. The high energy of these pulses poses a significant threat to many electronic systems, including those used to manage critical infrastructure. This work focuses on requirements for a potential portable measurement device and suggests the application of a method for this purpose, involving the use of a D-dot sensor and a rapid A/D converter. The applied converter enables recording the time waveform on the measuring chain output, also in the case of repetition and time duration of HPM signals. The authors also present a quantitative description of signal processing by the analogue section of the measurement chain solution presented herein and suggest algorithms for digital processing of the signals, the objective of which is to minimize low-frequency interference in the process of reconstructing the time waveform of an electric field using numerical integration.

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In some circumstances, electromagnetic compatibility testing must be performed not in a specialized anechoic chamber, but in an open space. However, typical absorbers used in anechoic chambers to absorb incident radiation and to reduce the amount of rays reflected from the walls and the floor, such as ferrite tiles and graphite cones, are not suitable in an open space. In this work, we present the design and a test for the absorbing material, which can successfully be used in a tent or in a similar light and portable structure. The proposed composite material is flexible, has good absorbing and mechanical properties as well as low reflectivity. As an absorber, the nanocrystalline iron alloy with graphite, mixed with an elastomer was proposed. This material was additionally exposed to the ionizing radiation in the dose of 100 kGy in the radioactive gamma source (60Co). The permittivity, permeability, and the shielding properties of the material have been analyzed as well.