|
|
Analysis of the radiation of accordions and designing the spatial arrangement of microphones for their recording
Rapáč, Marek ; Musil, Jaroslav (referee) ; Jirásek, Ondřej (advisor)
This bachelor’s thesis deals with the analysis of the spectrum and directivity of three different accordions.Two of the analyzed instruments are piano accordions with standard basses, one accordion is a special type of piano accordion, the so-called bass accordion.The effect of the played tone and used register on the spectrum and on the directionality of the resulting tone is described. The resulting findings are also compared between different accordions. The final part of the thesis is devoted to the practical use of stereo microphone techniques for high-quality, faithful and listener-friendly recording of the accordion sound. In conclusion, these findings are evaluated and the most suitable stereo microphone technique for recording the accordion is presented here.
|
|
|
The influence of the diameter and depth of the hole in the whistle on the timbre and directionality
Borovičková, Barbora ; Mojdl, Edgar (referee) ; Jirásek, Ondřej (advisor)
This bachelor’s thesis examines the influence of the diameter and depth of the holes in the recorder on the timbre and directionality of the resulting tone. For measurements and subsequent data analysis, nine flute body prototypes were made from three different materials and with three different wall thicknesses. During the measurement, holes with different diameters were drilled into the prototypes. Thanks to this procedure, it was possible to separate desirable influences from undesirable ones. The measured data were analyzed in the Matlab environment.
|
|
|
Numerical simulation of of human voice propagation through the vocal tract and in the space around the body
Batelka, Jiří ; Hájek, Petr (referee) ; Švancara, Pavel (advisor)
This master's thesis handles description of the source-filter theory of voice production, anatomy of larynx, possible approaches to voice production modelling and selected works using these approaches in first chapter. Brief description of selected quantities used in acoustics and model creation follows. Models of only the head and head with female and male torso are created, including mesh testing to determine suitable element size. Models created in this thesis focus on description of voice propagation primarily in front of body and on influence of torso on sound propagation. Inclusion of torso results in fluctuations in frequency domain in range from 1 000 Hz to 8 000 Hz, more pronounced near lower frquencies. In transverse plane the presence of torso manifests in lower SPL in front of mouth and higher SPL on the sides for several frequencies. Regions with decrease of SPL in front of mouth are coindicent with frequencies, where higher SPL on sides in comparision with direction in front of the mouth is evident. These observations are in agreement with other works. No significant differences were observed between models with different torsos in the transverse plane. Below the transverse plane differences between models with different torsos can be observed, for example for some frequencies decrease in SPL isn't observed in front of mouth in directivity diagrams for model with male torso.
|
|
|
Graphomotor and Writing Development in Early Elementary Education
Mlčáková, Renata
The thesis focuses on the graphomotor and writing development in early elementary education. Some school beginners struggle with various difficulties while acquiring writing skills. In case of more significant difficulties that persist those may influence children's success at school in a negative way. Besides the confidence can be affected. The educationist should help to get over the writing obstacles and try to reduce the period of inadequate solution of difficulties which are fixed. The theoretical part summarizes knowledge about the graphomotor and writing development in early elementary education and its consequences. The thesis tries to pinpoint the necessary connection of discovered knowledge about script, preschool training for writing, early elementary writing teaching also diagnostic aktivity, prevention and intervention concerning difficulties. It directs attention to some crucial moments which may influence beginning of writing acquiring. The research deals with verification of practical usage designed relaxation graphomotor exercises - designed workbook of relaxation graphomotor exercises "Do You Want to Scribble and Also Write Well?" and five special exercises for graphomotor development of school beginners in early elementary writing. This part was based on pedagogical experiment. Within the...
|
|
|
The Analysis of mutes on trombone and trumpet timbre
Košař, Vojtěch ; Mojdl, Edgar (referee) ; Jirásek, Ondřej (advisor)
This work deals with the sound mute issues, specifically how they affect the timbre of a trombone and a trumpet, their sound spectrum, levels of individual harmonic tones, the presence of formants and the directional characteristics of individual tones played in various dynamics. A part of this work is also focused on the theoretical description of a trombone and a trumpet, including their brief history, their classification, the parts they are consisting of and the timbre. The theoretical part is further dealing with the description of mathematic functions like FFT or LPC analysis, which have been implemented in the MATLAB environment when creating the graphic dependents for this theme.
|
|
|
Graphomotor and Writing Development in Early Elementary Education
Mlčáková, Renata
The thesis focuses on the graphomotor and writing development in early elementary education. Some school beginners struggle with various difficulties while acquiring writing skills. In case of more significant difficulties that persist those may influence children's success at school in a negative way. Besides the confidence can be affected. The educationist should help to get over the writing obstacles and try to reduce the period of inadequate solution of difficulties which are fixed. The theoretical part summarizes knowledge about the graphomotor and writing development in early elementary education and its consequences. The thesis tries to pinpoint the necessary connection of discovered knowledge about script, preschool training for writing, early elementary writing teaching also diagnostic aktivity, prevention and intervention concerning difficulties. It directs attention to some crucial moments which may influence beginning of writing acquiring. The research deals with verification of practical usage designed relaxation graphomotor exercises - designed workbook of relaxation graphomotor exercises "Do You Want to Scribble and Also Write Well?" and five special exercises for graphomotor development of school beginners in early elementary writing. This part was based on pedagogical experiment. Within the...
|
|
|
Simulation of Sound Field of Multiple Sound Sources
Kohoutek, Jan ; Kurc, David (referee) ; Schimmel, Jiří (advisor)
The main task of this bachelor thesis is description of interaction of sound waves in field. To understand the whole topic important physical laws related to sound waves propagation are defined. It also deals with frequency and directional response of ideal point source which compares with real measured responses of direct-radiating electrodynamic loudpeaker. Thesis are shown some examples of sound fields on which are specified their behavior. It also desribe main properties for right functionality of line-array source. In practical part are measured acoustic pressure values which lead to creating a interpolation map of sound pressure level. This obtained map was compared with theoretical acoustic field. Part of this bachelor thesis is program which enable to simulate acoustic field created under variable sound and environment properties.
|
|
|
Sound emission directivity model
Zdvyhal, Marian ; Hájek, Roman (referee) ; Hejčík, Jiří (advisor)
This diploma thesis solves creation of a computing model of sound propagation for determination of acoustic pressure level around multiple point sound source with consideration of sound directivity of each source (compresor and fan). Thesis contains neccesary theoretical knowledge for creation of computing model and basics of sound measuring, theoretical computing model, measurement data of real unit and model configuration for real measured values. Computing code of the model in Visual Basic for MS Excel is a part of the thesis.
|
|
|
Unidirectional plasmonic antennas
Formanová, Veronika ; Hrtoň, Martin (referee) ; Kvapil, Michal (advisor)
This thesis deals with directional V-shaped plasmonic antennas. In the thesis, an analytical model of antenna emission is proposed. The results of analytical computations are compared with results of numerical simulations in Lumerical FDTD Solutions package. Also, the process of fabrication of such antennas by electron beam lithography and measurement of optical properties using Fourier infrared spectroscopy is described and measured antenna resonant spectra are shown. Finally, there is a proposal of an experiment to prove the emission directivity of fabricated V-shaped antennas.
|
|
| |
guest ::
