Univerzitná knižnica - Zborníky

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Accuracy of digital terrain model on forest roads using airborne LIDAR and UAV point clouds
(University of Žilina, 2023) Kardoš, Miroslav; Ferenčík, Michal
A sufficiently dense forest road network is a basic prerequisite for the professional management of forests on the basis of close to nature management. For the purposes of forest management, it is of great importance to determine the state of damage of forest roads, to plan their reconstruction and to calculate the costs of their repair. The dominant method for forest mapping is photogrammetry, which is currently combined with airborne laser scanning data. The combination of these two methods makes it possible to obtain up-to-date and representative forest and landscape information for the purpose of professional and sustainable forest management in the context of 'precision forestry', which is based on the use of detailed site-specific information for the planning, management and implementation of forestry activities. In this paper, we discuss the application of the mentioned remote sensing methods for modelling the surface of selected forest road sections and evaluating the elevation accuracy of the data used. From the point of view of the methods used, both appear to be very suitable for the purpose of detailed surface mapping, condition and damage assessment, or for the optimization and design of new roads.
ADS-B MESSAGES AS A SOURCE OF OPERATIONAL DATA IN AVIATION
(Žilinská univerzita v Žiline, 2020) Noskievič, Tomáš; Kraus, Jakub
Automatic dependent surveillance has been becoming one of the technologies for aircraft surveillance. ADS-B messages which are broadcast from the aircraft to the ground contain many valuable information about the state and position of the aircraft. This paper presents more options for airline and airport operators how to utilize the information derived from the ADS-B messages. Particularly it deals with unstabilized approach detection, evaluation of the navigation integrity and arrivals and departures recording.
Aerodynamic airfoils and their applications
(University of Zilina, 2021) Kamenická, Daniela; Bugaj, Martin
This work focuses on aerodynamic airfoils and their application. The significant aim of this work is to introduce and analyse different types of airfoils and their importance. The first part of the paper examines aerodynamic characteristics, airfoil geometry and brings the historical evolution of certain types of airfoils. The second part of the paper considers different databases, and closely examines the NACA database and its numerical labelling by looking at digit series label, which follows the acronym NACA, indicating the airfoil's shape. The main body of the paperillustrates the real-life application of chosen airfoils by examining horizontal and vertical stabilisers and wind turbines. The last part of the paperpresents the analysis of the application of chosen wing root and wingtip airfoils.
Aerodynamic profile drag
(University of Zilina, 2021) Sabo, Matej; Bugaj, Martin
Higher awareness of aviation sustainability and environmental impact creates more research on profile drag reduction. The basic principles of aerodynamic profile drag are described and its role within the total drag. The boundary layer is defined using mathematical and physical principles of fluid dynamics. There are two types of movement inside the boundary layer: laminar and turbulent. In these, their impact on profile drag is analysed. The profile drag of a wing has two sources: form drag and friction drag. Applications with the most impact, throughout history, on both types of drag reductions were reviewed. Because most of the total drag comes from friction, researchers focus more on it compared to form drag. The significant way of reducing friction drag is postponing the transition of laminar flow into turbulent. The control of laminar flow became crucial for reducing friction drag. In the last two decades, European Union supported multiple projects concerning laminar flow control. These advancements in the field are starting to get implemented and tested on new aircraft by manufactures.
AERODYNAMICKÉ POŽADAVKY NA VOZIDLA V KONTEXTU DALŠÍHO ROZVOJE ŽELEZNICE
(VTS pri Žilinskej univerzite v Žiline, 2023) Mergl, Emanuel
Aircraft airfoils
(University of Žilina, 2023) Haluzová, Kristína; Bugaj, Martin; Hrúz, Michal
This work deals with the airfoils of aircraft. First of all, it focuses on the general properties of wings. Furthermore, the work deals with the issue of various types of wing shape and compares individual shapes of airfoils, their properties and gradual development. Next, current wings of commercial aircraft are described, dealing with the materials used, types of winglets, mechanization of the wing and also different uses of the airfoils. The work also describes and compares wings of two famous commercial airliners – Boeing 737-800 and Airbus A320-200. In the end, the work also focuses on various concepts of the wings of the future, and how sustainability affects future development.
Aircraft recycling system optimalization and aircraft sections re-use possibilities after the end of their economic life
(University of Zilina, 2022) Chebeň, Juraj; Rostáš, Ján
Purpose of this article is to evaluate re-use of sections from retired aicraft for further usage and additional optimalization of recycling and re-use of materials used in aircraft construction. With hundreds of commercial airplanes retired every year, the need for innovative approaches in recycling process rises. The concept of re-using parts from retired aircraft is not new. Before scrapping, valuable parts are of course stripped of the airplane. The article assesses if there is possibility to re-use parts and sections that usually end up scrapped in aviation and under which circumstances. Its first part is focused on analysis of procedures currently utilized during aircraft recycling, including brief description of decomissioning process, current state aircraft recycling in general, processes of disassembly and dismantle, existing facilities, description of recycling of alloys and composite materials. Second part deals with legislative, technical and environmental options of aircraft recycling and re-using aircraft sections. Third part focuses describes current parts market, together with proposal how to make it more efficient, current and possible future trends concerning aircraft recycling and re-use of materials and comparison of recycling between USA and Europe
AIRLINE HUBBING CONCEPTS
(Žilinská univerzita v Žiline, 2020) Števárová, Lucia; Badánik, Benedikt
New forms of cooperation between airlines have been in place since nineties. Airline alliances have been formed among network carriers. Before, cooperation of airlines was based on bilateral agreements on code-sharing of their flights. For instance, in 1989 KLM and Northwest agreed on large-scale code sharing. Nowadays, three major alliances might be recognized - Star Alliance, SkyTeam and oneworld. Together, they count for two thirds of total number of available seat kilometres. Airlines in alliances benefit from extended network and economies of scope and are prone to gain competitive advantage over the market by being able to offer more O&Ds and multiple routings via their hubs. Furthermore, they might save cost by sharing their capacity, facilities (gates, premium lounges) and equipment with partner airlines. Airline networks are defined by served markets, number of destinations, their configuration and airline business models. There are two concepts of network structures recognised nowadays: Hub and spoke and Point-to-point. This paper offers insights to the Hub and spoke concept. First of all, it examines hubbing concepts in general, it describes detailed aspects that influence passenger connectivity and on top of that it offers different hub airports wave patterns and airline hubbing concepts.
Airport operation disruptions
(University of Žilina, 2022) Beťková, Kristína; Kazda, Antonín
Disruptive events have a very strong potential to create a problem, spreading onwards to different participants in the chain of air travel. To minimalize the negative effects, this paper focused on how an airport can deal with disruptive operations effectively. The target of this paper was to come up with a step-by-step method, that airports could follow when coming up with a plan on how to manage their operations during these events. In order to reach this goal, it was essential to understand the principles causing disruptions and furthermore, categorizing them respectively. In addition to that, we had to find out what is the contribution of each category to the overall state of delays. Thanks to interviews with professionals at different international airports, we were able to come up with plans of trainings and exercises as a part of the suggested strategy. At the same time, in the proposed plan, several factors were mentioned, which were considered as an important part of the operations during interruptions that airports should not forget about.
The airspace of SR and its protection
(University of Zilina, 2021) Fábryová, Natália; Novák Sedláčková, Alena
The paper deals with international regulations of airspace of the Slovak republic and its protection. The paper is focused on the sovereignty airspace and free route airspace. The state has complete and absolute sovereignty over the airspace located above its territory. Airspace protection is important for ensuring territorial inviolability of the Slovak republic. There are defined the categories and classes of airspace. The last chapter consist of a NATO Integrated Air and Missile Defence System, its history and especially its function. In this chapter is defined the idea of „air policing “, which means the protection of airspace itself that is performed during the peace. In this part is described the position of emergency fighter pilots at Airport Sliac and model situations, but also the real situations, when Slovak emergency fighter pilots had to interfere against the aircraft that lost connection with air traffic management.
AKTUÁLNÍ STAV V OBLASTI NETRAKČNÍCH SOUPRAV ŠKODA
(VTS pri Žilinskej univerzite v Žiline, 2023) Kundrata, Miroslav; Tížek, Jakub
Škoda Transportation a.s. a Škoda Vagonka a.s. jsou tradičními výrobci kolejových vozidel v České republice. Kromě standardních produktů, jako jsou tramvaje, elektrické jednotky anebo lokomotivy se v menším měřítku věnují i vývoji, výrobě a homologaci vozových souprav a osobních vozů pro regionální a dálkovou dopravu.
ALTERNATIVE ENGINE SYSTEMS AND THEIR IMPACT ON THE ENVIRONMENT
(Žilinská univerzita v Žiline, 2020) Novák, Andrej; Kováčik, Ľubomír; Lusiak, Tomasz
The article deals with the operational characteristics of alternative aircraft propulsion systems and their impact on the environment. Recently, the issue of alternative aircraft propulsion systems has been brought to the forefront. Particularly with reference to the environment, which in the case of aviation is represented by reducing noise emissions while reducing CO2 emissions. These issues are properly addressed by ICAO in its agenda, defining standards for reducing aviation emissions in Annex 16. The University of Žilina has special laboratories dealing with the environmental impact of aviation and subsequent research aimed at reducing it.
Analysis and consequences of Boeing 737MAX accidents
(University of Zilina, 2021) Letko, Matúš; Rostáš, Ján
This master´s paper deals with the analysis and consequences of Boeing 737 MAX aircraft crashes from several perspectives. With a chronological sequence and a clear summary of all important facts, this paper offers a comprehensive view of the origin of the whole situation, the subsequent development and includes all consequences of these accidents. Despite the great amounts of information published, it favors facts and scientifically based information, thus contributing to the creation of a factual and objective opinion. The result is a complex view and evaluation of the situation with respect to the conditions in the aviation industry. Finally, it adds value by deriving responsibility from all relevant actors and identifying the circumstances that contributed to the accidents.
Analysis of alternative control options fot the ROTAX 915 is engine
(University of Žilina, 2023) Plochová, Jana; Šajbanová, Kristína
This article focuses on analyzing the possibilities of alternative management of the ROTAX 915 IS aircraft engine using the ECU MASTER electronic control unit. The article examines how the use of ECU MASTER could become a beneficial alternative to the traditional manufacturer's control system. The new control system would ensure lower costs for purchasing ECU and reduce the number of sensors required to operate the engine. This would achieve a lower weight of the entire system, which is very important for aircraft in terms of fuel efficiency and cost savings.
Analysis of implementation instrument approaches for hems heliports
(University of Zilina, 2021) Posluch, Samuel; Pecho, Pavol
In recent years, the trend of using a helicopters in the operation of the helicopter emergency medical service (HEMS) has been increasing. The reason is the wide range of uses of the helicopter, fast and safe transport of wounded people using new copters. Nevertheless, it is not possible to operate flights in poor weather conditions with a sufficient number of interventions. There is a need to develop new procedures for flying even under conditions other than VFR flight rules. The current state of helicopter technology in Slovakia allows it and therefore it is appropriate that new procedures using GNSS be created to establish a safe flight. The aim of the analysis is to evaluate the input factors available to the operator and to create a design approach based on the legislative requirements for the use of GNSS systems on the selected heliport. The resulting approach design can be used as one of the options for creating procedures. Such proposals could also be implemented on other operational bases, for the creation of a network of instrument approach or departure systems, which would create space for increasing the safety of helicopter emergency medical service in Slovakia.
ANALYSIS OF JET ENGINE COMPONENTS HEAT RESISTANCE IMPROVEMENT BY TBC COATING
(Žilinská univerzita v Žiline, 2020) Čerňan, Jozef; Janovec, Michal; Cúttová, Miroslava
The operation of jet engines in aviation is a very challenging task also in view of the high demands on the safety of such an operation. One of the most dangerous phenomena that affects the safe operation of these engines is the unstable work of the compressor. The object of the research in this article is to find appropriate and simple way to improve heat resistance of the MPM-20 experimental engine components, suffered by high thermal load, which resulted in the destruction of its gas turbine. A metallographic and microscopic analysis was carried out on the experimental specimens improved by TBC coating for decreasing of thermal conductivity. The results of experiments with TBC coatings shows decrease of the sample temperature for samples covered with TBC coating comparing to samples withou it. This fact can contribute to the development of new surface treatment of jet engine components with higher heat resistance and better reliability.
Analysis of new progressive diagnistic methods in the area of aircraft maintenance
(University of Zilina, 2021) Supuka, Matej; Hrúz, Michal
In the area of aircraft maintenance, we commonly meet with the problem of corrosion, detection of which is one of the primary obstacles. Implementation of modern sensing techniques has a potential to bring many benefits. The objective of this work is to analyze technologies, their potential applications, and viability of switching to autonomous detection using computer aided sensing. Primary source of information were research articles from science databases such as ResearchGate and ScienceDirect. Available documents were analyzed and subsequently, useful information was extracted. First part deals with theretical knowledge about corrosion, based on which potential technologies were chosen. Those were then described, and their viability was analyzed, based on how well they could achieve our goals. Selected technologies have shown potential, however necessary solutions could not be found to enable fully switching tou autonomous computer detection. Although data acquired show many potential benefits that could arise from partial implementation of these technologies combined fith old fashioned visual inspection.
Analysis of satellite navigation systems usable in general aviation
(University of Zilina, 2022) Gahír, Jakub; Novák, Andrej
This paper is mainly focused on solving the current issues of satellite navigation systems and subsequent analysis. The paper is systematically divided, while the first chapter focuses mainly on the definition of satellite navigation systems, their use in general aviation and introduction of specific examples, their division in terms of operation and a description of advanced satellite navigation systems. The second chapter deals with the methodology of work, analyzes the sources and the chosen procedure for solving and researching the issue. The third chapter is the main one and is focused on the analysis and research of satellite navigation systems, defining input parameters such as: accuracy, continuity, or integrity of navigation services. It also compares research with the current state of the issue and evaluates analyses, suggests possible changes and directions of further research in satellite navigation industry.
Analysis of selected aircrafts suitable for PPL training
(University of Zilina, 2021) Matula, Dominik; Bugaj, Martin
The main goal of the paper is based on the analysis to define the criteria for selecting an aircraft suitable for PPL training. We achieved the main goal by meeting two sub-goals. The first sub-objective is the analysis of training organizations in Slovakia, on the basis of which we have selected entities for the second sub-objective thus the analysis of selected aircrafts suitable for PPL training. In this work we analyze three, most used training aircrafts for PPL training in Slovakia. We analyze selected aircrafts in terms of three main parts, which include, analysis of technical parameters, analysis of flight characteristics and analysis of operating parameters. Based on the given analyzes, we obtained an evaluation of the characteristics of selected aircrafts, their individual advantages and disadvantages. Other results of the work include the evaluation of criteria that are suitable for aircrafts designed for PPL training. This work can be applied in practice, especially when deciding on the selection of a training aircraft for a student or training organization.
Analysis of selected vital functions of a pilot during flight
(University of Žilina, 2023) Rimarčík, Timotej; Chodelka, Frederik
Pilots work in distinct environment and there are many requirements they must fulfill to ensure the safe operation of an aircraft. However, there are also some psychological elements, that might be difficult to deal with, such as stress and high workload, while performing difficult flight tasks. This article explains what causes stress and high workload, and how does it affect pilots. Some of the vital functions of human body can be used to measure stress and high workload. The final part will deal with some research, using modern methods to measure stress and high workload during different flight phases, to upgrade cockpit ergonomics and procedures in aviation.