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There is a common practice to calculate orbital trajectories of space objects like satellites and space debris using Two-Line Element Sets (TLEs). However, TLEs provide rather coarse parameters for fine orbit computation and their precision varies with age of their issue and position of the satellite. The paper evaluates such induced position determination error using the comparison of a position calculated from TLE data for a small CubeSat class satellite and a position obtained from the on-board custom GPS receiver that is a part of such satellite payload. The analyses of the impact of satellite position at the orbit, i.e., a dependency of position error on satellite geographical latitude, and impact of the ageing of TLE data in frame of position and velocity vector were made. There was shown that use of TLE data can bring some significant errors in calculation of predicted satellite position which can affect performance and efficiency of some related tasks like steering the ground station antenna for communication with the satellite or planning the satellites operations namely for the classes of small and amateur satellites.

Stone is one of the most common materials used as a building material in central Europe for centuries. Historical objects are endangered by degradation procedures coming from physical, chemical and biological weathering agents.The weathering process itself should be analysed in detail in order to prevent historical objects by application of proper restoration cleaning techniques. Within our research, a historical sandstone block was analysed during time to monitor biological changes on the surface. The object of interest is situated in the immediate vicinity of Charles Bridge in Prague, which is protected as a UNESCO heritage site. This site was chosen due to high overall humidity all year long. For investigation of the year- round process of biodegradation hyperspectral sensor was used.  In the first place, data were processed using four vegetation indices (NDVI, RGRI, CRI1 and VREI1). All vegetation indices indicate that vegetation is thriving and subject to normal seasonal change. The second chosen method of data processing is to use spectral reflectance curves and their subsequence processing by Spectral Angle Mapper (SAM) classification algorithms. A decline in vegetation with the onset of autumn and during the winter months was detected.

Within the research of historical stone monuments and artefacts we often encounter the question of determining the original material provenance. The answer to this question is often very complicated due to the frequent impossibility of taking samples for petrographic analysis, which in many cases cannot fully identify the place of origin. It is therefore necessary to pay attention to non-destructive survey methods applicable in the field. For the purpose of non-destructive stone provenance determination, the method of reflectance spectroscopy in the near and mid-infrared spectrum (1000–2500 nm) can be used. It is a very simple and effective method that can be implemented in-situ. This method is based on Earth remote sensing methods and is commonly used for the identification of minerals and soils, but it can also be used for the identification of rocks with a certain experimental set-up and a suitably chosen algorithm for the evaluation of the measured data. For each material, a unique spectral reflectance curve can be defined, which expresses the dependence between reflectance percentage and wavelength. The curve can then be compared with known spectra in a pre-prepared database to find the one that is most similar to the one under study and thus identify the material. The applicability of the method was verified, among other things, in the context of a survey of the historic stone masonry of the southern staircase of St. Vitus Cathedral in Prague, Czech Republic. Obtained results confirm the high potential of this method.

Traces of stone working are an integral part of natural stone objects and artefacts of historical value. Each preserved trace does not only carry a value in determining the type of tool used, but also provides information about the historic stonemason’s work process and technology. For this reason, it is desirable to assess the restoration method’s influence on the change in surface topography. The effect of restoration interventions was investigated on five stone artefacts, three of ‘opuka’, one of sandstone and one of limestone, four of which showed historic working traces. For this purpose, selected restoration methods—chemical, mechanical and laser—were used. The examined artefacts were accurately photogrammetrically captured before and after the restoration interventions in order to assess and evaluate changes in the degree of preservation of the traces. Fine results using common tools were achieved in terms of geometric quality, level of detail and the documentation’s predictive power. The models’ geometric accuracy is in the single tenths of mm, as well as the matching of the two datasets (before and after).

The condition of underlying rock and footing masonry affects significantly technical condition of historical monuments. The caused subsidence may affect the origin of construction cracks, which may directly influence its stability. These impacts are mostly indirect and they are difficult to identify due to information lack. Footing masonry and long-term changes in the underlying rock are hidden underneath existing ground and floor level. If records related to foundations do exist, they are frequently fragmental. Monitoring can be source of information due to direct outputs and data describing footing masonry and subsoil conditions. Examples of monitoring instrumentation and gained results, determination of conditions of masonry together with principles of monitoring applied in the project focused on the Broumov Group of Churches are presented in the paper. Within the monitoring instrumentation, Fibre Bragg Gratings monitoring technology has been used and is described in the paper as well.

Corporate management understands the importance of proving the quality of their products as well as other aspects, particularly environmental and safety issues in business connections and their possible negative impact on the company's competitiveness and image. A data analysis was carried out based on a questionnaire research conducted in a selection group of Czech businesses with the objective to identify the reasons for introducing and using a management system, or to identify difficulties and problems in introducing it. The questionnaire research was statistically processed using analytic classification, hypotheses testing as well as a correlation analysis. The objective of the research was to validate or invalidate the hypotheses concerning the measures taken by a business in implementing and maintaining a quality management system (QMS), problems in its implementation, and to analyse competitive advantages and influence on the image. The research results confirmed that internal reasons for QMS implementation prevail in national businesses. Nevertheless, the main problem is the complexity of QMS/ understanding of the QMS by employees. An implemented QMS motivates the personnel, however, only a small number of enterprises use it to motivate their employees. The main benefits quoted by the respondents were improved company process management and relations between the processes, increased customer satisfaction as well as improved corporate image. A quality management system helps organisations to introduce system and order. Corporate processes are systematically managed, which significantly contributes to meeting the business objectives of a company. Having integrated the implemented QMS in their organisation, the respondents demonstrated they can effectively work with it and flexibly react to the changes faced in the present market environment.

When investigating historical building stones, we often encounter an issue concerning the original material provenance identification. Addressing this issue is usually rather complicated due to the unavailability of samples to conduct a petrographic analysis that itself often cannot fully identify the site of acquisition. It is therefore imperative to focus on non-destructive research methods applicable in the field. Great emphasis is placed on interdisciplinarity with experts from a variety of fields contributing to the achievement of relevant results. The reflectance spectroscopy method in the near- and mid-infrared spectral range (1000–2500 nm), a simple and effective method to be applied in situ, is used for non-destructive identification of stone provenance. A unique spectral reflectance curve representing the reflectance in percentages versus the wavelength can be defined for each material. Consequently, the curve can be compared with spectra in the pre-prepared library in order to find the one best corresponding to the investigated curve to identify the material. The applied traceology methods are used to determine the approximate age of the stone elements to specify the achieved results, and not least, they are compared with the results of archival and art history research. Within our research, these methods were applied during the investigation of historical stone artefacts and masonry in St. Vitus Cathedral, located in Prague, Czech Republic. The achieved results corroborate a high potential of the selected methods and approaches.

Stone monuments maintenance requires the systematic approach which should be based on the cooperation among specialist through more branches, especially from humanities, natural and technical sciences. The main aim of this article is to present the benefit of the cooperation among geologists and civil engineers and share preliminary results of the Czech Ministry of Culture project DG20P02OVV021 “Stone surface topography and its application in stone element restoration field”. Historic stone surfaces often contain stonemasons tool traces as an undoubtable part of historical monument value. The study and protection of the testimony of past is therefore very important. As a part of our project, we are conducting field and laboratory research of historic stone surfaces bearing the original tool traces. The studied area is the Prague urban conservation zone for its stone monuments richness from Romanesque to present days. First, the geological research of the stone masonry surface is conducted in the cooperation with archaeologists. The tool traces are documented, and the state of stone is described. Because of the negative influence of weathering processes on the stone durability, respectively tool traces, we decided to monitor the chosen historical stone surface using the hyperspectral analysis. Based on the analysis results we will be able to better understand the behaviour of stone surface and traces on it during the time.

The paper is focused on a system of investigation of hidden parts of historical buildings as footing masonry and subsoil affecting significantly their technical conditions and stability. These impacts are mostly difficult to identify in time and there are often indirect producing differential settlement resulting in development of systems of cracks in the building masonry. Reliable analysis of the building supporting system shall precede any remedial actions or reconstructions. If the demonstration of the above negative impacts on the building becomes visible, it can indicate our late entry in to solving the problems with deterioration of the foundation system. Investigation boring and instrumentation of boreholes for high accuracy 3D displacement monitoring with local levelling system is presented in the paper illustrated by an example of one baroque church of the Broumov group of churches. This activity was followed by analyses of building stones and determination of degree of the footing masonry and subsoil deterioration together with careful input data for numeric modelling estimation.