Flyover noise is a problem that affects citizens, primarily those that live near or around places with high air traffic such as airports or military bases. Such noise can be of great annoyance. The focus of this thesis is in determining a method to create a high fidelity sound source simulation of rotorcraft noise for the purpose of producing a complete flyover scenario to be used in psychoacoustic testing. The focus of the sound source simulation is simulating rotorcraft noise fluctuations during level flight to aid in psychoacoustic testing to determine human perception of such noise. Current methods only model the stationary or time-average components when synthesizing the sound source. The synthesis process described in this thesis determines the steady-state waveform of the noise as well as the time-varying fluctuations for each rotor individually. The process explored in this thesis uses an empirical approach to synthesize flyover noise by directly using physical flyover recordings. Four different methods of synthesis were created to determine the combination of components that produce high fidelity sound source simulation. These four methods of synthesis are: a) Unmodulated main rotor b) Modulated main rotor c) Unmodulated main rotor combined with the unmodulated tail rotor d) Modulated main rotor combined with the modulated tail rotor Since the time-varying components of the source sound are important to the creation of high fidelity sound source simulation, five different types of time-varying fluctuations, or modulations, were implemented to determine the importance of the fluctuating components on the sound source simulation. The types of modulation investigated are a) no modulation, b) randomly applied generic modulation, c) coherently applied generic modulation, d) randomly applied specific modulation, and e) coherently applied specific modulation. Generic modulation is derived from a different section of the source recording to which it is applied. For the purposes of this study, it is not clearly dominated by either thickness or loading noise characteristics, but still displays long-term modulation. Random application of the modulation implies that there is a loss of absolute modulation phase and amplitude information across the frequency spectrum. Coherent application of the modulation implies that an attempt is made to line up the absolute phase and amplitude of the modulation signal with that which is being replaced (i.e. that which was stripped from the original recording and expanding or contracting to fit the signal to which it is applied). Specific modulation is the modulation from the source recording which is being reconstructed. A psychoacoustic test was performed to rank the fidelity of each synthesis method and each type of modulation. Performing this comparison for two different emission angles provides insight as to whether the ranking will differ between the emission angles. The modulated main rotor combined with the modulated tail rotor showed the highest fidelity and had a much higher fidelity than any of the other synthesis methods. The psychoacoustic test proved that modulation is necessary to produce a high fidelity sound source simulation. However, the use of a generic modulation or a randomly applied specific modulation proved to be an inadequate substitute for the coherently applied specific modulation. The results from this research show that more research is necessary to properly simulate a full flyover scenario. Specifically, more data is needed in order to properly model the modulation for level flight. / Master of Science

Rotorcraft flyover noise has long been a field of study for researchers. This is because for many people, the sounds produced by these vehicles are found to be extremely annoying. The focus of this thesis is to recreate the time-varying rotorcraft noise at the source for a single emission angle. Then, through interpolation between emission angles, produce a simulated flyover at the source that can then be propagated to a receiver. This will allow for the creation of a simulated flyover without the need of having to use a physical aircraft, or pre-existing data from some type of data collection means, such as a microphone array. The current methods are limited to a predefined length of data in order to synthesize signals. It has been documented that synthesizing flyover noise, from direct use of physical flyover recordings through an empirical approach, yields a high fidelity signal, as long as both unmodulated and modulated components are present. In order to extend these signals indefinitely, models for the amplitude and phase modulation must be developed. A band-limited random process will be explored for both the amplitude and phase modulations. An overlap-add technique, as well as a randomization technique and a modified phase modulation signal, defined as the "residual", will also be attempted in order to model the phase modulation. The results from this work have successfully found a means in which to produce a viable model of the amplitude modulation. Further investigation is still required in order to produce a model of the phase modulation which results in a high-fidelity model that can be extended indefinitely. / Master of Science

The subject of these graduation thesis is a draft of adaptation the existing indented intersection of roads I/50 and II/416 in Slavkov u Brna. Thesis include design of construction work intersection, which was made on the basis of direction research actual state and consequent capacitance calculation.

This thesis deals with a design of the bridge for highway D47 crossing the valley. From three alternative solution is chosen solution of a double-girder. The longitudinal direction of the structure is designed as eight span structure. The lenght of the spans is 25 + 6 x 35 + 25 m. Detailed design of the structure selected variants of the bridge is carried out according to limit states including consideration of the impact of construction on the bridge of his design. static model is carried out as a whip. It is elaborated a detailed structural analysis and it is developed drawings and visualization of the bridge.

The subject of this diploma thesis is design of arch bridge across the highway. Has been elected self-anchored structure with span of arch 60 m and trapezoid bridge deck from prestressed concrete. The load effects is calculated by software Scia Engineer including time dependent analysis. The supporting structure is assessed for the ultimate limit state and serviceability limit state. Static assessment is done by hand calculation according to CSN EN 1992-2. Part of the thesis is drawing and visualization of the bridge.

Master’s thesis describes the design of a highway bridge over the road II/434 and inundation territory. There are some studies designed, from which the main structure was designed as a prestressed concrete double-girder bridge with 5 spans. Loading, design and assessment of structure is solved according to applicable standards CSN and EN. Calculate the effects of the load are carried in calculation program Scia Engineer 2015. Design and asses are carried only by the manual calculation. The thesis includes used materials, construction process, statically analysis and drawing documentation.

My diploma thesis deals with design of the bridge number 202 on expressway in Slovakia. The bridge leads across the road number I50 (between Trenčín and Bánovce nad Bebravou) and railway number 130 (between Trenčín and Chynorany). For each course there is a separate super-structure. Only left super-structure is considered for the work. The box girder with four spans is chosen from three variations. This bridge is designed according to limit states, construction´s influence on design is taking into consideration. Structural model of construction is made as a spatial bar model. Structural analysis, well arranged drawings and visualization are elaborated in this thesis too.

The subject of this thesis is the design and assessment of the bridge across the expressway and the deep valley in section Hričovské Podhradie - Lietavská Lúčka of highway D1 in Slovakia. The box girder structure with eleven spans was chosen of three variants. For each course there is a separate structure. The design of the bridge is carried out according to limit states including consideration of the impact of construction. The assessment of the construction is carried out using the beam model. The appendix contains structural analysis, drawings and visualization of the bridge.

The diploma thesis deals with the design of a continuous prestressed bridge structure transferring the D56 motorway on the Frýdek-Místek bypass. The bridge bridges the local watercourse of the river Olešná, Příborská street and road II / 473. Three studies were proposed, from which a variant of a two-beam continuous prestressed monolithic slab was selected and elaborated. The static model and calculation of its internal forces took place in the program SCIA Engineer 20.0. The calculation is performed according to valid standards, limit states, which also includes the effects of construction. The work also contains detailed drawing documentation.

Diploma thesis deals with design pre-stressed road bridge over the radial road from Ostrava, railway ČD and tram in Brno. There are designed 4 studies, from which variation parabolic double-chamber girder with 8 spans is chosen. Thesis solves construction process and static calculation includes time analysis. It is elaborated a detailed structural analysis and bridge is considered a proposal to limit states for temporary and permanent design situations according to European standards - Eurocodes. It is developed drawings and visualization of the bridge.