In the study of mixed graphs, a common question is: What are the necessary and suffcient conditions for the existence of a decomposition of the complete mixed graph into isomorphic copies of a given mixed graph? Since the complete mixed graph has twice as many arcs as edges, then an obvious necessary condition is that the isomorphic copies have twice as many arcs as edges. We will prove necessary and suffcient conditions for the existence of a decomposition of the complete mixed graphs into mixed stars with two edges and four arcs. We also consider some special cases of decompositions of the complete mixed graph into partially oriented stars with twice as many arcs as edges. We employ difference methods in most of our constructions when showing suffciency. 2

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Observing the dynamic interaction between stars and their close stellar neighbors is key to establishing the stars’ orbits, masses, and other properties. Our ability to visually discriminate nearby stars is limited by the power of our telescopes, posing a challenge to astronomers at small observatories that contribute to binary star surveys. Masks placed at the telescope aperture promise to augment the resolving power of telescopes of all sizes, but many of these masks must be manually and repetitively reoriented about the optical axis to achieve their full benefits. This paper introduces a design concept for a mask rotation mechanism that can be adapted to telescopes of different types and proportions, focusing on an implementation for a Celestron C11 Schmidt–Cassegrain optical tube assembly. Mask concepts were first evaluated using diffraction simulation programs, later manufactured, and finally tested on close double stars using a C11. An electronic rotation mechanism was designed, produced, and evaluated. Results show that applying a properly shaped and oriented mask to a C11 enhances contrast in images of double star systems relative to images captured with the unmasked telescope, and they show that the rotation mechanism accurately and repeatably places masks at target orientations with minimal manual effort. Detail drawings of the mask rotation mechanism and code for the software interface are included.

To add to the understanding of the structure and evolution of Delta Scuti stars, 167 Delta Scutis north of -01 degrees declination and brighter than 13th magnitude have been observed spectroscopically. A method for calculating rotational velocity values and Hydrogen-Beta color indices for the stars in the data set with no previously published values is developed, using the stars in the data set brighter than 7th magnitude. Rotational velocity values for four stars with previously unknown values and Hydrogen-Beta index values for five stars with previously unknown values are calculated.

Práce se zabývá výzkumem v oblasti odmrazování světlometu. Jejím cílem je vytvoření numerického simulačního modelu, který dokáže předpovídat průběh odmrazování, zároveň tak může odhalit nedostatky při návrhu světlometu. Na simulační modelu jsou testovány proměnlivé parametry, výsledkem práce je nalezení optimálních podmínek, které zajistí validní výsledky simulace při současné úspoře výpočetního času.

The vehicle body was measured by using ATOS 3D scanner. Measured data from the ATOS 3D scanner were applied to make a 3D model of vehicle body and to make a 3D model of whole vehicle by using computer program Pro/ENGINEER. The model of vehicle was made with a view for future use of CAD model. Surface of the vehicle model was used for computation of vehicle aerodynamics – aerodynamic static pressure distribution by using CFD software Star-CCM+.

The main content of this master’s thesis is design of RNAV SID and STAR routes for Brno Tuřany Airport. The study analyses usage of current conventional instrument arrivals and departures published for the aerodrome and describes its TMA. The new precision RNAV routes and the terminal area are designed based on the indentified information. A detailed construction of the chosen departure procedure is enclosed.

Master’s thesis deals with the aerodynamics of racing vehicle for various settings of clearance and tilt of body. First is described the theory of aerodynamics and flow. It was necessary to build the CAD model of racing car for analysis. Assembly of this model is the next chapter of the master’s thesis. This is followed by CFD analysis, where is displayed a simplified model of the vehicle. This part describes the overall process and setting in the CFD program. In conclusion, the results are summarized for each setting.