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V návaznosti na modernizaci Sítě permanentních stanic GNSS České republiky (CZEPOS), která byla provedena v letech 2018–2019, byla v uplynulých letech dokončena modernizace služeb CZEPOS kompatibilních také se signály evropského GNSS Galileo a čínského BeiDou. Pokračoval rozvoj aplikací Databáze bodových polí (DBP). Bylo zavedeno podrobnější členění vrstev, které slouží k zobrazení bodových polí na webu, modernizovány byly také vlastní webové aplikace. After the modernization of the Czech Network of Permanent Stations GNSS of the Czech Republic (CZEPOS), which was performed in 2018–2019, modernization of CZEPOS services has completed during past years, which are compatible also with Galileo and BeiDou signals. Development of applications of Database of Geodetic Control (DBP) continued. More detailed division of the levels were applied, which are used for a presentation of the geodetic control points on the web. Relevant web applications were modernized as well.

Prace prezentuje metodiku tvorby dermoplastických preparatů celých ryb. Je primarně urcena ucitelům přirodopisu a biologie různých stupňů skol. Metodika vychazi ze zmapovani a studia znamých metod preparaci ryb v historii i soucasnosti. Jejich empirickým ověřenim a obohacenim o nove postupy a technologie vznikl navod, který ma usnadnit výrobu preparatů celých ryb jako didaktických ucebnich pomůcek. Metodika, mimo jine, popisuje problematiku ziskavani a uchovavani ryb. Nezbytným předpokladem pro taxidermii je hluboka znalost anatomie ryb. Metodika může být využita i jako voditko k připadne anatomicke pitvě. Výstupem prakticke casti prace jsou dermoplasticke preparaty ryb, ktere se staly soucasti sbirky Katedry biologie a environmentalnich studii Pedagogicke fakulty Univerzity Karlovy, kde slouži pro vzdělavaci ucely. Metodika hodnoti nove zkusenosti ziskane v procesu tvorby preparatů. Na zakladě teto reflexe poskytuje doporuceni týkajici se výběru potřebných materialů a nastrojů, volby metod, jejich výhod a nevýhod, jako je napřiklad vytvařeni oci pro výsledne modely ci použiti modernich plnicich hmot, polystyrenových forem apod. Podava take didakticke naměty pro pedagogy a upozorňuje na možnosti přesahu tematu výroby dermoplastických preparatů v ramci interdiscipli­narnich vztahů.

Prace se zabýva sledovanim pocetniho stavu a denni aktivity feralniho holuba (Columba livia f. domestica) v lokalitě pražskeho Smichova. Výzkum byl zaměřen na zjistěni, zda je mistni skupina holubů z hlediska denni aktivity vazana na potravni navyky konzistentni, nebo se děli na dvě podskupiny, z nichž jedna zůstava na lokalitě a druha odleta za potravou na větsi vzdalenost za město. K výzkumu byla použita metoda znackovani holubů křidelnimi znackami s nasledným pozorovanim jejich výskytu a telemetricke sledovani minivysilackou se schopnosti zaznamu momentalni zeměpisne polohy (GPS). Celkem bylo odchyceno a oznackovano deset ptaků, jimž byly aplikovany křidelni znacky, a jeden jedinec, který byl pozorovan GPS telemetrii. Uvedenými metodami se podařilo zjistit, že holubi se skutecně na dane lokalitě děli na dvě skupiny. Jedna se během dne pohybuje v bezprostředni blizkosti nocovistě, kde si obstarava potravu skladajici se předevsim z odpadků a zaměrneho krmeni mistnim obyvatelstvem, zatimco druha skupina odleta 6 km zapadnim směrem na pole za město. V době setby a sklizně obili se na sledovanem uzemi v Praze přes den nevyskytovali žadni holubi.

This study addresses differences in the material properties due to the influence of the printing direction, UV degradation and the use of differently coloured materials. The specimens were manufactured employing PolyJet technology from the Vero material (VeroBlue, VeroYellow, VeroMagenta). Subsequently, the specimens were subjected to tension and compression testing. Ageing is simulated via the exposure of the specimens to solar UVA and UVB for 15 and 30 days (the calculated daylight UV exposure for half a year and a whole year, respectively). The differences in the material properties were also determined according to the types of material. The results were then subjected to a statistical analysis.

The article describes skeleton features of the avian species. It is aimed at specifc features, developed solely at the avian skeleton. Te article mentions some features of the dinosaur taxon, especially those that distinguish the birds and the dinosaurs. Te article emphasizes the evolutionary trend of the birds, where the structural schematics of the skeleton trends towards three features present only in the avian species. Tese features are: 1) short tail with no muscles, 2) strongly developed pectoral muscles and V-shaped clavicle bone (furcula), 3) specifc built of legs that are primarily used for running.

This paper shows a method of calculating the hazard rate of the non-homogeneous Markov chains using different homogeneous probability matrices for several hundreds small time intervals (using default parameters settings — the number of the intervals can be adjusted to balance accuracy/time-consumption ratio). The method is compared to a pessimistic method based on homogeneous Markov chains and used to calculate the hazard rate of the hierarchical Markov chain. The hazard rates of the blocks are calculated independently and the non-homogeneous approach allows us to use them to calculate the hazard rate of the whole system. The independent calculations are significantly faster than the calculation of a single model composed of all models of the blocks.

Nowadays, there are two main approaches to cultural heritage documentation: a precise documentation by several techniques such as professional close range photogrammetry, classical geodetical measurement and 3D scanning, or a simple documentation using non expensive devices and instruments, often based on free software. In many projects it is not possible to use precise and expensive instruments for time, transportational, financial and authoritative permission reasons. At the Laboratory of Photogrammetry at the CTU Prague, we are focused on both types of documentation and the necessary visualisation of outputs; the long-term and very important aim of our research in this field is to develop small, inexpensive devices and test appropriate technology for the 3D documentation of cultural heritage objects. There is our prototype of an optical correlation system, which uses a motorised calibrated digital camera on a linear base. The second part shows several open source photogrammetric systems compared with Photomodeler PMSC and Agisoft Photoscan software. On a case project, based on our own data from German-Czech expeditions in Peru, the simple photogrammetric documentation of a small archaeological object joined with reverse engineering has been demonstrated.

The 3D scanning is nowadays a commonly used and fast technique. A variety of type’s 3D scanners is available, with different precision and aim of using. From normal user´s point of view, all the instruments are very expensive and need special software for processing the measured data. Also transportation of 3D scanners – poses a problem, because duty or special taxes for transport out of the EU have to be paid and there is a risk of damage to dismantling of these very expensive instruments and calibration will be needed. For this reason, a simple and automated technique using close range photogrammetry documentation is very important. This paper describes our experience with the software solution for automatic image correlation techniques and their utilization in close range photogrammetry and historical objects documentation. Non-photogrammetrical approach, which often gives very good outputs, is described the last part of this contribution. An image correlation proceeds well only on appropriate parts of documented objects and depends on the number of images, their overlapping and configuration, radiometrical quality of photos, and surface texture.

This paper presents an experimental investigation on stocky column web panels of semi-rigid beam-to-column joints exposed to fire conditions in order to verify an analytical prediction model. Recent experimental studies show that the degradation of material properties and high axial forces, due to restrained thermal expansion of beams at elevated temperatures, significantly affect the moment–rotation response of the joints. The component method originally established for the evaluation of the joint behaviour at ambient conditions can be adopted for elevated-temperature cases. Recently developed mechanical models for joints may not be accurate as the column web component is simultaneously subjected to bending moments and axial forces. This paper focuses on the component column web in shear in order to identify the key parameters which affect joint behaviour in shear at elevated temperatures. This experimental work was conducted on three extended end-plate connections subjected to both ambient and elevated temperature conditions. After validations by test results, detailed finite element simulations were performed for a series of parametric studies at other elevated temperatures. Both experimental and numerical results are finally compared with analytical predictions.

Gas chromatographic study of the reaction between epichlorohydrin and methanol By means of the first three intermediate products the effect of the initial molar ratio of epichlorohydrin to methanol upon the distribution curve of the adducts has been followed. Besides the initial molar ratio, the ratio of rate of propagation to rate of initiation considerably affects the distribution. Quantitative results obtained by gas chromatography have been corrected for response at detection and compared with the results computed according to a mathematical model of the polyaddition of epichlorohydrin. It was found that the degree of occurrence of polyaddition is lower than was expected from the results of prior kinetic studies. By combining the results of gas chromatography and of the mathematical model, some kinetic problems of complex polyaddition reactions can be solved. A qualitative analysis of the results of gas chromatography confirmed for the initial addition steps a theoretical hypothesis of the formation of 2n isomers, where n is the number of moles added.

Gas chromatographic identification of 3-chloro-2-hydroxypropyl ethers of aliphatic primary alcohols This paper summarizes the results obtained by the gas chromatographic identification of ten alkyl 3-chloro-2-hydroxypropyl ethers with alkyl chains in the range of C 1 —C 10 . As the best liquid phase polyglycerol can be recommended; the best column temperature is 130° for the C 1 –C 7 derivatives and 150° for the C 6 –C 16 derivatives. The relationship between the number of carbon atoms in the alkyl chain and the logarithm of the retention time is linear in the range of C 3 –C 16 .