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Algebraic approaches to elementary excitations in media with broken spatial or time-reversal symmetry
Erb, Kay Condie ; Hlinka, Jiří (vedoucí práce) ; Mokrý, Pavel (oponent) ; Schranz, Wilfried (oponent)
Název práce: Algebraické přístupy k elementárním excitacím v prostředích s narušenou invariancí vůči prostorové nebo časové inverzi Autor: Kay Condie Erb Ústav: Fyzikální ústav Akademie věd České republiky Školitel: Ing. Jiří Hlinka, Ph.D., Fyzikální ústav Akademie věd České republiky Abstrakt: Strukturní fázové přechody vykazující narušení makroskopické symetrie lze rozdělit do 212 nemagnetických druhů (species) podle vzájemné prostorové ori- entace bodových grup obou fází. Zařazení do daného druhu implikuje řadu uni- verzálních vlastností přechodu jako např. počet makroskopických doménových stavů nízkosymetrické fáze a jejich rozlišitelnost pomocí parametrů uspořádání. V této práci byla studována rozlišitelnost makroskopických doménových stavů pomocí všech parametrů uspořádání, které se transformují jako vektory nebo jako vektorům podobné veličiny, tzv. bidirectory. Pro řešení úlohy byl navržen počítačový algoritmus, který umožnil explicitní výpis výskytu všech vektorových a vektorům podobných parametrů uspořádání a to nejen pro 212 nemagnetických species, ale i pro všech 1602 magnetických species, která zahrnují také přechody mezi krystalografickými bodovými grupami šedými a...
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Systém pro haptickou odezvu a jeho spolehlivost
Horpatzká, Michaela ; Hlinka, Jiří (oponent) ; Janhuba, Luboš (vedoucí práce)
Práce se věnuje koncepčnímu návrhu a hodnocení spolehlivosti systému haptické odezvy pro piloty malých letounů kategorií UL2, EASA CS-LSA, EASA CS-VLA a EASA-CS-23. Koncepční návrh je rozdělen na tři části. V první je shrnut vývoj testování haptického systému na leteckém simulátoru, dále pak jsou rozebrány možnosti zapojení systému do letounu pro letovou zkoušku a ve třetí části jsou nastíněny možnosti pro zástavbu do letounu. Součástí poslední části koncepčního návrhu je analýza spolehlivosti systému a shrnutí možných problémů při zástavbě systému do letounu.
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Modelling of health monitoring signals and detection areas for aerospace structures
Šplíchal, Jan ; Hlinka, Jiří
This paper is focused on Structural Health Monitoring (SHM) for aerospace use. It analyses the performance of commercially available finite element (FE) software packages for the simulation of propagation of ultrasonic guided waves (UGW) in typical aerospace structures. The purpose of the research is to support activities leading to the introduction of UGW based health monitoring on aerospace structures, as well as to support the design of future structures with integrated health monitoring. Activities are demonstrated on panels with growing complexity (adding different materials, sensors, damage types etc.). FE simulations are used to identify “detection areas” of UGW sensors. This output can be directly applied to the design of future aerospace structures with an integrated SHM system (to ensure the proper planning of the placement of UGW sensors).
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Integrated method utilizing graph theory and fuzzy logic for safety and reliability assessment of airborne systems
Janhuba, Luboš ; Hlinka, Jiří ; Koštial, Rostislav
This paper presents integrated algorithm for airborne system safety and reliability assessment. In general aviation (mostly up to EASA CS-23) and non-military unmanned aerial vehicles industry, safety and reliability assessment process still relays almost exclusively on human judgment. Recommended practices define processes for system modelling and safety assessing are based on analyst understanding of a particular system. That is difficult and time-consuming process. Commercial computation aids are extremely expensive with restricted (or closed) access to the solution algorithms. Together with this problem, rapid development of modern airborne systems, their increasing complexity, elevates level of interconnection. Therefore, safety and reliability analyses have to continuously evolve and adapt to the extending complexity. Growing expansion brings in the field of unnamed aerial vehicles systems which consist of items without relevant reliability testing. Presented algorithm utilizes graph theory and fuzzy logic in order to develop integrated computerized mean for reliability analysis of sophisticated, highly interconnected airborne systems. Through the usage of graph theory, it is possible to create model of particular systems and its sub-systems in the form of universal data structure. Algorithm is conceived as fuzzy expert system, that emulates decision making of a human expert. That brings opportunity to partially quantify system attributes and criticality. Criticality evaluation increases level of assessment correlation with real state of system and its attributes.
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Aircraft leading edges minor damages detection based on thermographic survey of electrical anti-icing system
Koštial, Rostislav ; Janhuba, Luboš ; Hlinka, Jiří
Aircraft leading edge is one of the most important subjects of aircraft scheduled maintenance. Leading edge as part of the slot on transport aircraft is not critical to fatigue stress in most of the cases. However, leading edge is extremely vulnerable to the accidental damage in combination with environmental damage. Maintenance is usually provided by visual inspection before every flight. Nevertheless, development of anti-icing system based on contact electrical heating opens possibility to thermographic Nondestructive Testing (NDT) methods usage. These methods could detect minor damages, which are visually undetectable especially in the case of composite materials. This paper describes possibility of thermographic methods (using anti-icing system) application as mean of leading edge minor damage detection.
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The Integrated Method Utilizing Graph Theory and Fuzzy Logic for Safety and Reliability Assessment
Janhuba, Luboš ; Vališ, David (oponent) ; Třetina, Karel (oponent) ; Hlinka, Jiří (vedoucí práce)
Doctoral thesis creates an integrated algorithm for airborne system safety and reliability assessment. In ´general aviation´ (mostly up to EASA CS-23) and ´non-military unmanned aerial vehicles industry´- safety and reliability assessment process still rely almost exclusively on human judgment. Current processes of system modelling and assessing are based on analyst understanding of a particular system. That is a difficult and extremely time-consuming process. Commercial computation aids are extremely expensive with restricted or even closed access to the solution algorithms. Together with this problem, the rapid development of modern airborne systems and their increasing complexity elevates the level of interconnection, safety and reliability analyses which have to be continuously evolved and adapted to the extending complexity. The given integrated method utilizes the graph theory and fuzzy logic in order to develop integrated and partially computerized mean for reliability analysis of sophisticated and highly interconnected airborne systems. Through the use of the graph theory, it is possible to create the model of particular systems and its sub-systems in the form of universal data structure. It is even possible to assess various systems and items interrelations. And it also enables to evaluate particular item position and topology within the system and on the global level. Extended criticality evaluation is conceived as the fuzzy expert system that emulates decision making by a human expert. The integrated method also provides additional mean how to evaluate the system design. Fuzzy robustness assessment evaluates e.g. system diversity rate, redundancy, separation and environmental protection.
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XXIII Czech-Polish seminar: Structural and ferroelectric phase transitions
Hlinka, Jiří ; Pokorný, Jan ; Bubnov, Alexej
This is the Book of Abstracts for the XXIII Czech-Polish Seminar (CPSEM-2018 conference) held in Kouty on May 21 - 25, 2018. The special objective of the conference is expressed in the conference subtitle: Structural and Ferroelectric Phase Transitions. The continuous worldwide interest to this conference series is proving that it has a respected position within the series of International/European conferences covering all interdisciplinary field of the research related to structural and ferroelectric phase transitions. At the CPSEM-2018 conference more than 110 participants from 14 countries all over the world presented 16 invited lectures and selected 36 oral contributions. About 60 posters were presented during two poster sessions.
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Conceptual design of training aircraft with electric propulsion
Seman, Matúš ; Zikmund, Pavel (oponent) ; Hlinka, Jiří (vedoucí práce)
This thesis is focused on conceptual design of electric powered training aircraft, using certification guidelines CS-LSA. Designing process of geometrical and aerodynamic characteristics is primary based on statistics of certificated aircrafts in this particular category. The following calculation of performance stabilities and flight performances is based on knowledge of aerodynamic polar. The calculation of the polar is also part of this thesis. The last part of the thesis consists of construction design of the front part of fuselage and engine static structural analysis of engine mounts.
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Koncepční návrh moderního avionického systému pro letoun kategorie EASA CS-23
Vaňousová, Jana ; Hlinka, Jiří (oponent) ; Janhuba, Luboš (vedoucí práce)
Diplomová práce se zabývá koncepčním návrhem moderního avionického systému pro letoun kategorie EASA CS-23. Práce obsahuje rozbor předpisů EASA CS-23 a EU-OPS, rozbor trhu avionických systémů pro tuto kategorii letounů a dále návrh architektury avionického systému. Bezpečnost a spolehlivost navrženého systému je zhodnocena pomocí analýzy FMEA. Hodnocení důsledků poruch je provedeno na základě doporučení poradního oběžníku AC 23.1309-1E. Závěr práce zahrnuje zhodnocení potenciálního napadení systému třetí osobou.
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