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Changes in the morphometric and anatomical parameters of shoots and leaves of Acer platanoides L. after rejuvenation pruning
Get PDFThe influence of rejuvenation pruning on changes in anatomical and morphometric characteristics of annual shoots and leaves of Acer platanoides L. in the conditions of Dnipro (Ukraine) has been investigated. In the first two years after pruning, a significant intensification of growth processes is observed. The length and diameter of annual shoots, the number of internodes and leaves, and the area of the leaf blade increased. Pruning has a particularly noticeable effect on the increase in the length of annual shoots and the area of the assimilation surface of the shoot – in the first year after pruning, they increased by 4.6 and 3.2 times, respectively. In rejuvenated plants, a thickening of the leaf blade occurs, mainly due to the development of a spongy parenchyma. In the fourth year after pruning, the intensity of growth processes decreases and differs little from the control (unpruned) plants. The leaves of crowned plants are damaged more significantly than those of unpruned ones. In four years, the rejuvenated plants restore their crowns well
APPLICATION OF DISCONTINUOUS SOLUTIONS IN BOUNDARY ELEMENT METHOD FOR THE BENDING PROBLEMS OF KIRCHHOFF PLATES WITH AN ARBITRARY CONTOUR
Get PDFThe discontinuous solutions represent a new direction for the indirect Boundary Element Method (BEM) in the indirect formulation. Discontinuous solutions represent those functions, which when crossing certain lines, the transverse deflection, the slope angle, the bending moment and the generalized shear force may have jumps. These can be used to solve important problems for which the existing methods do not have solutions or a satisfactory accuracy, such as: plates of arbitrary contour, presence of defects, mixed boundary conditions, contact problems, infinite domains etc. In this paper, we describe the methodology of application and the numerical implementation of discontinuous solutions for the bending problems of plates with an arbitrary contour in the classical theory (Kirchhoff). For this purpose, programming codes were developed in the Matlab language, which allowed to calculate the displacements and efforts in the plate. The obtained results were compared with the Finite Element Method (FEM) for different mesh densities
DIRECTING THE UNIFORMITY OF THE LEVEL OF PULSE CHARGING OF LI-ION BATTERIES USED IN AUTOMOTIVE INDUSTRY
Get PDFThe lithium-ion (Li-ion) battery is widely used in modern electronics, serves as a power source in electric vehicles and for energy storage in renewable energy systems. The strengths of Li-ion batteries are their high energy density. Modern Li-ion batteries can include arrays of cells, the lifetime of which is determined by factors that depend on charge-discharge characteristics. Li-ion batteries connected in series have different aging rates due to different capacities. The capacity deviation increases as the battery has been used, generating an increase in compensation current, which continues to increase until ignition. To solve this problem, a pulse device and a charging method in a charge equalization battery were proposed in this paper. A numerical simulation of how to charge real Porsche Taycan car batteries was performed. The results obtained confirmed the effectiveness, the energy losses did not exceed 2% of the battery capacity. A bench diagram was developed for studying and programming the operating modes of battery control units for hybrid and electric cars
CLIMATE RISK OF SHALLOW TOURISTIC LAKES: A CASE STUDY OF LAKE VELENCE (HUNGARY)
Get PDFThe European shallow lakes used primarily for tourism are subjected to a large amount of environmental pressure, and climate change is adding new problems and aspects to them: a complex analysis of processes and connections is necessary to make appropriate decisions and strategies. In this reseach research, using literature review and precedent analysis, it has been reviewed the climate risk of a Central European lake, as well as the natural conditions and landscape change processes determining its sensitivity. It was analysed the ecological and economic effects of the record low water levels of 2021-22, focusing on processes. It was determined which of the current land uses can be considered risky or sensitive in terms of climate change. It was found that natural processes are uniformly leading towards pre-regulation character, low water levels facilitating the regeneration of flora and fauna. However, the dominant land use is dependent on artificially elevated water levels, and therefore serious economic problems have arisen. Beaches, bathing, and angling tourism are the most vulnerable to climate change
WRITING WORKSHOPS IN FRENCH FOREIGN LANGUAGE AT THE ALGERIAN UNIVERSITY
Get PDFThis research takes stock of a didactic approach to remediation undertaken in a Frech foreign language class at the University of Blida 2. The experiment was initiated by a double observation. The first is the unsatisfactory quality of the texts produced by my students in the course of written comprehension-production, and the second being the negative relationship expressed by the latter vis-à-vis the literary modules. To remedy this, I designed a didactic device aimed at developing the scriptural skills of learners through the reading of literary short stories. The results generated by this study reveal a significant increase in the public concerned at the local level (microstructure) but especially on the global level (macrostructure) of the texts produced by the participants. Also, the data collected show the role of writing workshops in motivating learners to write in a foreign language. In addition, the literary short story has proven to be an effective educational tool to use in the language class to help learners improve their target language
LINO BIANCO – THE RING METAPHOR AND THE SPIRIT OF SOFIA AND OTHER ESSAYS
Get PDFThis article is a review of the publication The Ring Metaphor and the Spirit of Sofia and other essays by Lino Bianco. The book was published by Kite Group, Ħamrun, Malta, 2022 with ISBN 978-9918-23-053-2 (Hardback) / 978-9918-23-054-9 (Paperback). Bianco is an architect and an academic and Ambassador Emeritus of the Republic of Malta to the Republic of Bulgaria
Analysis of the use of geothermal heat pumps for heating and cooling of individual residential buildings
Get PDFToday, humanity is beginning to realize the problem of the growing shortage of natural energy sources. The prices of these sources are rising uncontrollably and will continue to rise in the future. As the Republic of Moldova does not have its own fossil fuels fields and is totally dependent on foreign imports, the implementation of renewable energy sources technologies becomes vital. In this sense, the usage of closed type geothermal heat pumps with direct heat exchange in new and reconstructed residential buildings to replace traditional heating boilers is beneficial. They can be especially effective in areas where there are no gas supply pipelines. The purpose of the paper is to determine the perspectives of geothermal heat pumps using in residential buildings in the Republic of Moldova climatic conditions. Examples with implemented geothermal heat pumps and project solutions for heating/cooling and hot water supply systems for three individual residential buildings in the southern region of the Republic of Moldova were analyzed for task implementation. During the 2020-2021 heating season, it was not necessary to use the additional reserve heat source for the examined objects
The role of basil, thyme and tarragon in reducing the content of nitrite in meat products
Get PDFReducing the content of nitrites and nitrates in food, including meat and meat products is a current issue. More and more studies are being done to reduce these synthetic food additives by using vegetative additives. This paper examines the issue of reducing nitrite content in meat products. The role of the basil, thyme and tarragon on nitrites and nitrates content in meat products is presented. The study showed the possibility of reducing the content of nitrites and nitrates in Lacta sausages, by using basil extract (BE 0,1%) by 0.4-0.94%, (BE 0.2%) by 0.80-1.88%. (BE 0.3%) by 1.20-2.82%; by thyme extract (ThE 0.1%) by 0.56-071%, (ThE 0.2%) by 1.12-1.42%, (ThE 0.3%) by 1.68-2.13%; by tarragon extract (TE 0.1%) by 0,08-0.66%, (TE 0.2%) by 1.16-1.32. (TE 0.3%) by 0.24-1.98%, maintaining the quality and safety of meat products
ATTITUDE CONTROL OF THE NANOSATELLITE USING A HYBRID FUZZY ALGORITHM BY MEANS OF THE REACTION WHEELS
Get PDFNumerous application fields of automation the industrial processes have demonstrated favorable outcomes with modern control algorithms that rely on artificial intelligence. Therefore, some researchers have endeavored to implement these algorithms in the attitude control of satellites by evaluating their performance in simulated scenarios. However, due to the associated cost and risks, there is a scarcity of experimental data available for testing new attitude control algorithms on a real satellite. To address this issue, simulation of satellite positioning based on the dynamic model of the satellite with reaction wheels was carried out to perform a comparative analysis of a hybrid proportional integral and derivative (PID) fuzzy control algorithm and a classical PID control algorithm, regarding the analysis of the obtained performances. The obtained results indicate that using a Hybrid Fuzzy PID control algorithm produces better performances, than the PID control algorithm
LAND USE WEB MAP OF MOLDOVA CREATING USING WEB-BASED MAPPING SOFTWARE ARCGIS ONLINE
Get PDFThe motivation for creating of an interactive map for school is the desire to collect all the necessary information from different sources into one web map to facilitate and standardize the process of teaching geography of the Republic of Moldova, and due to the interactivity of the map to increase student academic achievement and motivation. In the article the methodology of the research, which is carried out within scientific project, the creation of Land Use Web school map of Moldova is considered. The content of the Land Use Web Map and interface screenshots showing functions of interactive map are presented in the article. In the main part of the article, the technology of the creation of Land Use map is described developed by means of work with spatial data of Laboratory of Geomorphology and Ecopedology of Institute of Ecology and Geography and using tools of Web-based mapping software ArcGIS Online. The first result of the study is the description of the technology by which any other thematic web map can be created. The second result is the Land Use web map of Moldova, which through the Internet can be used in any country of the world by students and school teachers