- ItemShear strength of thin web – influence of lighting openings and diagonal tension(Taylor & Francis, 2016-04-11) Horák, Marek; Píštěk, AntonínThis article provides information about stress analysis of thin beam webs with and without lighting openings. The study described in this paper was carried out in order to investigate the influence of circular lighting openings in planar webs on critical web shear force, distribution of transverse web deformations, and also strain and stress distribution in the web plate. The main goal was to compare pre- and post-buckling behaviour of a thin web with and without lighting openings under shear load.
- ItemStandard and Future-Potential Methods for Safety and Reliability Assessment Illustrated by an Airborne Electric System Example(Taylor & Francis, 2016-01-14) Janhuba, LubošThis paper is focused on the description of complex airborne safety and reliability assessment methods mostly used in general aviation. It is a short presentation of standard approaches, principles and methods for the evaluation of aircraft critical systems. There are many techniques that may be used during safety and reliability assessment of an airborne system. The complexity of airborne system components and their interconnection is rapidly growing. System safety assessment is an essential part of an airplane certification process. Therefore, the means of safety and reliability have to evolve. This paper presents one of future potential concepts of safety and reliability analysis. The conclusion of this paper gives a brief summary of a standard and a future-potential technique.
- ItemUnmanned Aerial Vehicles for Alient Plant Species Detection and Monitoring(International Society of Photogrammetry and Remote Sensing (ISPRS), Copernicus, 2015-09-02) Dvořák, Petr; Müllerová, Jana; Bartaloš, Tomáš; Brůna, JosefInvasive species spread rapidly and their eradication is difficult. New methods enabling fast and efficient monitoring are urgently needed for their successful control. Remote sensing can improve early detection of invading plants and make their management more efficient and less expensive. In an ongoing project in the Czech Republic, we aim at developing innovative methods of mapping invasive plant species (semi-automatic detection algorithms) by using purposely designed unmanned aircraft (UAV). We examine possibilities for detection of two tree and two herb invasive species. Our aim is to establish fast, repeatable and efficient computer-assisted method of timely monitoring, reducing the costs of extensive field campaigns. For finding the best detection algorithm we test various classification approaches (object-, pixel-based and hybrid). Thanks to its flexibility and low cost, UAV enables assessing the effect of phenological stage and spatial resolution, and is most suitable for monitoring the efficiency of eradication efforts. However, several challenges exist in UAV application, such as geometrical and radiometric distortions, high amount of data to be processed and legal constrains for the UAV flight missions over urban areas (often highly invaded). The newly proposed UAV approach shall serve invasive species researchers, management practitioners and policy makers.
- ItemPilot-aircraft haptic feedback tests(Emerald Publishing Limited, 2020-10-25) Zikmund, Pavel; Horpatzká, Michaela; Dubnický, Lukáš; Macík, Miroslav; Jebáček, IvoThis paper deals with a pilot-aircraft interaction with a haptic feedback. The haptic feedback is mediated by active elements in control stick and rudder pedals. The paper presents results of tests carried out on a flight simulator and flight tests.
- ItemDynamic soaring of unmanned aerial vehicle within airliner wake vortex in climb regime(SAGE, 2017-11-01) Zikmund, Pavel; Matějů, JiříThe paper presents an analysis of an unmanned aerial vehicle gliding in an airliner wake vortex using the dynamic soaring principle. The presented results provide insight into energy balance and controllability of the unmanned aerial vehicle flying in an airliner wake vortex.