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Abstract

Archaeological research in the area of the chateau park uncovered the relic of the Gothic church of St. Elisabeth, dated to the second half of the 13th century. It is a single-nave building with a rectangular finish (length 25 m, boat width 13 m, presbytery width 10.5 m). The church probably had an older predecessor - a wooden structure on a stone foundation, dating from the mid-13th century. At the same time, the church site was a burial place: a grave of a young woman and a 1.5-year-old child, dated 13th/14th century were found outside the presbytery wall. In the presbytery, there were 3 graves of men dating back to the 14th century. It is very likely that these are the Lords of the Wallenstein family. Archaeological research in graves in the Church of St. Elisabeth unearthed a small collection of animal bone remains. The occurrence of bones of young and mature cattle and domestic fowls, which are abundant in the archaeozoological assemblage, indicates the prevailing meat consumption of these animals. The butchering marks on their bones document removal of meat from the carcasses.

Abstract

Problems regarding the security of maritime infrastructure, especially harbours and offshore infrastructure, are currently a very hot topic. Due to these problems, there are some research projects in which the main goal is to decrease the gap and improve the methods of observation in the chosen area, for both in-air and underwater areas. The main goal of the paper is to show a new complex system for improving the security of the maritime infrastructure by means of many methods of observation – such as thermovision, optical devices, and radar systems – generally by means of an electromagnetic wave as a carrier of information in the air and acoustical methods in water. The system can be applied to the protection of maritime infrastructure as well as the coastal zone.

Abstract

The lifting surface model is widely used in screw propeller design and analysis applications. It serves as a reliable tool for determination of the propeller blade mean line and pitch distribution. The main idea of this application was to determine the blade shape that would satisfy the kinematic boundary condition on its surface with the prescribed bound circulation distribution over it. In this paper a simplified lifting surface method is presented – in which the 3D task for the entire blade is replaced by a set of 2D tasks for subsequent blade section profiles.

Abstract

Knowledge and study of breeding birds’ biology is essential to understand the dynamic, assess productivity and identify threats. The population of booted eagles (Hieraaetus pennatus) was studied during three consecutive breeding seasons (2013−2015) in the Chettabah forest. Each year, arrivals of Booted eagles are recorded during March (15 individuals in 2013, 12 in 2014 and 11 in 2015). For the three years of study, the mean breeding pair’s density was 1.23 ± 0.153/km2, incubation period ranged from 33 to 38 days, whilst the frequency distribution of clutch size was 67.6% for 2 eggs, 27% for 1 and 5.4% for 3. Amongst the 63 eggs monitored, 55 hatched. No significant variation in hatching rate was observed during the 3 years (90% in 2013, 76.19% in 2014 and 84% in 2015). The comparison of breeding parameters with those reported in Spain showed a noticeable similarity. Further investigations should be conducted to improve the provision of information to support sound management interventions of this North African population.

Abstract

Snowbed vegetation is one of the most sensitive alpine vegetation type to the climate change, because shortened period of snow cover has essential impact on the snowbed environment. We focus on its changes in the Western Tatras, which is a part of the Western Carpathians (Slovakia). The assessment of changes in snowbed vegetation is based on the method of pair comparison. In 2016–2018, we resampled 21 historical phytocoenological relevés of Festucion picturatae and Salicion herbaceae alliances from 1974 and 1976. Historical data include 45 species, while recent data include 50 species. We observed a decrease in the frequency of species characteristic for snowbeds and, on the other hand, an increase in that for strong competitors, especially grasses and small shrubs from adjacent habitats. According to Ellenberg’s ecological indices, there is some increase in temperature and decrease in light ecological factors in snowbed habitats. In S. herbaceae data, a statistically significant increase in the average species number was observed with new species that penetrated from the adjacent habitats. Changes in species composition between historical and recent data are confirmed by Non-metric multidimensional scaling (nMDS) ordination diagram. Linear mixed-effect models showed big variability in factors that have impact on phytodiversity; nevertheless, temperature is the most significant factor.

Abstract

This paper presents a description and the results of experimental studies of the deformation, friction and structural damping occurring in foundation bolted joints of propulsion plant components and auxiliary machinery that is rigidly mounted on sea-going ships. The rigid mounting of these devices to the ships’ structural foundations can be implemented in a traditional way, i.e. on chocks made of metal (usually of steel), or in a modern way, i.e. on chocks cast of resin, specially designed for this purpose. The main goal of this study is to perform a comparative analysis of these two solutions and to give a scientific explanation for why chocks cast of resin perform better in machinery seatings than the steel chocks traditionally used for this purpose. The paper consists of two parts. Part I presents the details of the rigid mountings of machinery to the foundations, and contains the results of experimental studies performed on a model of a foundation bolted joint with a traditional steel chock. Part II contains the results of similar studies carried out for a model of a bolted joint with a modern chock cast of resin. Next, a comparative analysis and evaluation of the results obtained for both investigated bolted joints was carried out, and conclusions were formulated to highlight important aspects of the problem from the point of view of science and engineering practice.

Abstract

Modernisation of the existing river fleet adapted for the local conditions of the Middle and Lower Vistula can be considered as a solution to slow down the progressive decrease of river transport in this area. The implementation of technical improvements, smart technologies and enhancement of transport performance may partially solve the problem of growing demand for multimodal transport of containers and oversized loads in a shorter perspective than the expected period of planned revitalisation of the river. The paper presents investigations on the modernisation of river convoys adapted to the current navigational conditions of the Lower Vistula. The different options have been discussed by the authors with river fleet operators and the best recognised solution was agreed to be the use of river convoys combining modernised motor barges and the pushed barges previously used in this area. Improvement of the transport profitability, reduction of fuel consumption, air pollution and noise can be achieved at minimum costs by modernisation of the main power-propulsion systems of outdated motor barges and the implementation of innovative steering systems on pushed barges. The demand for power-propulsion and manoeuvring performance of modernised convoys is discussed in the paper.

Abstract

To implement the Mehlich 3 method in Polish agro-chemical laboratories, limit values for deficiency of B, Cu, Fe, Mn and Zn in soil for wheat were developed. The values were developed on the basis of 1921 fields with wheat, evenly distributed throughout Poland. Soil samples were collected from these fields in 2016, together with the plants growing on them, at the stage of stem elongation (BBCH 30/31). The concentration of micronutrients was determined in all soil and plant samples. In addition, pH, texture, and the content of organic carbon and available phosphorus were determined in soil samples. Moreover, grain yield after wheat harvest was estimated for all fields. Limit values were developed by two independent methods: 1) the regression equation method and 2) the so-called high yield method. In the first case, the limit microelement concentration in soil was calculated from the equation describing the relationship between the bioaccumulation factor (R/G) and a specific soil feature (n=1921). The bioaccumulation factor is the quotient of the concentration of a micronutrient in a plant (R) and its concentration in the soil (G) determined by the Mehlich 3 method. The equations were constructed using the Stagraphics program. For each micronutrient, 8 models were tested in search for the equation with the highest determination coefficient r2. Limit values were calculated after substituting the critical value of microelements in the plant (R) to the selected model and transforming the equation accordingly. The basis of the second method was to separate the “high yield group” ≥7.0 t ha−1 (n=578) from the entire data set. In this group, lower quintiles for the Mehlich 3-concentration of individual microelements in soil were calculated. The lower quintiles (QU1) were taken as limit values. It was assumed that QU1 is a good indicator of the lowest micronutrient concentration in the soil at which a yield of 7.0 t ha−1 or higher can be obtained. The comparison of the values calculated with the regression equations method and the high yield method showed their similarity, which confirmed the reliability of these values. The proposed values define the limit for low microelements concentration in soil determined with the Mehlich 3 method, below which wheat fertilization with these nutrients is recommended.