Patients with circumscribed visual field defects can perceive them while looking at a surface with small black and white spots flickering randomly at high frequency (such as the white-noise field of a TV screen following the end of transmissions for the day). This autonomous perception of scotomata can be used as a screening method, to perform subsequent manual or automatic grid perimetry with the same TV monitor, concentrating on the defective part of the visual field alone. The results of white-noise scotometry used to examine the visual fields of 161 patients are presented. It appears that the test is capable of identifying suprageniculate homonymous hemianopias, since patients either do not observe them at all in the white-noise field or only to a far lesser degree. In addition, the blind spot and some congenital visual field defects are not observed as visual field defects at all in the white-noise field. However, all acquired circumscribed defects caused by lesions of the first, second, or third neuron are readily seen in the white-noise field if the patient is capable of stable fixation.

The study outlines the geometric analysis of motions executed by the Stewart platform and operated in the environment of a simulator for driving learning to be used by disabled people. The analysis was carried out on the basis of results obtained from the resolved kinematic problem for the inversed platform.

Determining the location of objects, for example roadheader in a hard coal mine, is a task that should be automated in the conditions of state-of-the-art mining. Current solutions do not meet the user’s expectations due to the lack of the possibility of automation, maladjustment to the environment of a hard coal mine or not meeting the legal requirements. The article describes the initial stage of work on an automatic system for determining the position of machines in difficult underground conditions, including the analysis of requirements and constraints, an overview of available solutions, technologies and algorithms, as a result of which devices were selected for further tests. To determine the location, it is necessary to take distance measurements with high accuracy, despite the disturbances resulting from the working environment. Ultrasonic devices were selected and then tested under various operating conditions, including different distances between the transmitter and receiver as well as different directions and intensities of air movement that could distort the measurement results. During tests, sufficient accuracy, as well as other parameters, of the ultrasonic transducers were confirmed, allowing for distance measurements in the required range, suitable for use in the real-time locating system (RTLS) being developed.

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