bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling and Simulation of Mechatronic Systems for Predictive Performance Analysis
Authors: Verma Deepak
Published: June 2023

Modelling and simulation play a pivotal role in the development and analysis of mechatronic systems. The integration of mechanical, electrical, and control components in mechatronic systems creates complex dynamics that require comprehensive understanding and predictive performance analysis. This paper presents a thorough exploration of the use of modelling and simulation techniques for predictive performance analysis in mechatronic systems. This paper provides an in-depth examination of the role of modelling and simulation in the context of mechatronic systems for predictive performance analysis. The presented research underscores the significance of these techniques in the design and optimization of mechatronic systems, enabling engineers to make informed decisions and enhance system performance. By leveraging modelling and simulation, engineers can create virtual environments that replicate the behaviour of mechatronic systems, facilitating comprehensive analysis and contributing to the advancement of this interdisciplinary field.The paper explains emphasizing the growing importance of modelling and simulation in the field of mechatronics. The ability to predict the performance of mechatronic systems through virtual experimentation enhances the design process, reduces the risk of failure, and increases the overall system performance. As technology advances, the integration of modelling and simulation with emerging technologies, such as artificial intelligence and machine learning, opens up new avenues for further advancements in predictive performance analysis of mechatronic systems.
Human-Cantered Design Approaches in Mechatronics for Improved User Experience
Authors: Singh Amit Kumar
Published: June 2023

In the rapidly evolving field of mechatronics, human-cantered design (HCD) approaches have gained significant attention as a means to enhance user experience. Mechatronics, which combines mechanical engineering, electronics, computer science, and control systems, aims to develop intelligent and interactive systems. However, the success of mechatronic systems relies not only on their technical functionalities but also on how well they align with users' needs and expectations. This abstract explores the significance of human-cantered design approaches in mechatronics and their potential to improve user experience.In the outcome, human-cantered design approaches play a crucial role in mechatronics for improving user experience. By involving users from the early stages, employing iterative design cycles, and considering usability and emotional factors, mechatronic systems can be developed to be more user-friendly, efficient, and engaging. The integration of HCD approaches leads to systems that align with users' needs, preferences, and expectations, ultimately resulting in improved user experience and increased user acceptance of mechatronic systems. As mechatronics continues to advance, the adoption of human-cantered design approaches will remain essential in ensuring the successful development and deployment of user-centric mechatronic systems.
Numerical and Experimental Analysis of Combustion Characteristics of Gas Turbine Engines
Authors: Lila Manish Kumar
Published: June 2023

Advanced computational fluid dynamics (CFD) methods were used to carry out the numerical analysis. It was created a three-dimensional CFD model to represent the intricate flow and combustion processes inside the gas turbine engine. Fuel injection, combustion kinetics, and the effects of turbulence were all taken into account by the model. In order to analyse several combustion factors, such as temperature distribution, species concentrations, and flame propagation, numerical simulations were run.Experimentation was done in order to verify the numerical results and understand the combustion properties better. To simulate the operational circumstances of a gas turbine engine, a test setup was created. Measurements of combustion parameters, including pressure, temperature, and emissions, were made and compared to the numerical forecasts. The computational model might then be verified and improved as a result.The findings of this study offer insightful information about how gas turbine engines behave during combustion. The temperature distribution, species concentrations, and flame propagation within the engine were all correctly predicted by the numerical models. The experimental observations showed good agreement with the expected values, confirming the accuracy of the numerical model. This thorough examination aids in the comprehension of gas turbine engine combustion processes and can be used as a foundation for future design enhancements and performance enhancements.
Development and Optimization of Wind Turbine Blade Design for Enhanced Efficiency
Authors: Pandey Rohit
Published: June 2023

The improvement and optimisation of wind energy system performance and efficiency depend heavily on the design of wind turbine blades. Wind power has emerged as a viable option for environmentally friendly electricity generation in response to the rising demand for renewable energy sources. The structural properties and aerodynamic performance of a wind turbine's blades have a significant impact on its efficiency.This study focuses on the systematic creation and efficiency optimisation of wind turbine blade designs. The study uses a multidisciplinary strategy that incorporates optimisation, structural analysis, and aerodynamics. The goal is to increase power generation while maintaining the structural integrity, cost-effectiveness, and safety of the blades.The research starts with a thorough examination of the strengths and weaknesses of the current designs for wind turbine blades. To assess the performance of various blade shapes, various aerodynamic theories, computational fluid dynamics (CFD) simulations, and wind tunnel measurements are used. The issue of wind turbine blade noise is also included in the study. To lessen the influence of noise on the environment, noise reduction techniques like trailing-edge serrations are being researched. The project also investigates the use of cutting-edge materials, like carbon fibre composites, to lighten the blades without sacrificing their structural integrity.The results of this study are anticipated to have a big impact on wind turbine blade design. It is projected that the optimised blade designs will improve wind energy systems' overall efficiency by boosting power output and lowering aerodynamic loads. While the use of noise reduction measures enhances the environmental friendliness of wind turbines, structural analysis ensures the safety and dependability of the blades.
Investigation of Representation Theory for Algebraic and Geometric Applications
Authors: Bhadula Rakesh Chandra
Published: June 2023

Understanding the algebraic and geometric structures that form in diverse mathematical areas depends heavily on the study of representation theory. The significance and uses of representation theory in both algebra and geometry are briefly discussed in this abstract.The primary goal of representation theory is to understand how linear transformations on vector spaces can represent abstract algebraic objects like groups, rings, and algebras. Representation theory offers a strong framework to analyse and interact with these structures using the methods and tools of linear algebra by linking algebraic structures with linear transformations.The representation theory has significant effects on algebra. Through the examination of the representations that go along with a group, it allows us to examine its composition and behaviour. One can learn more about the internal structures and underlying symmetries of groups by breaking representations down into irreducible parts. This has implications for number theory, combinatorics, and quantum physics, among other fields.Understanding symmetries and transformations of geometric objects in geometry depends critically on representation theory. The investigation of shape and space symmetry is made possible by representation theory, which links geometric objects with linear transformations. This has uses in a variety of disciplines, including physics' study of symmetry groups, differential geometry, and crystallography.A crucial area of research, representation theory has extensive uses in both algebra and geometry. It is indispensable in many branches of mathematics and opens up new directions for research and discovery because it can reveal the underlying structures and symmetries of abstract algebraic objects.
Design and Optimization of Numerical Methods for Solving Inverse Problems
Authors: Khantwal Deepak
Published: June 2023

. The purpose of inverse problems is to identify the unknown causes or parameters based on observable effects or measurements in a variety of scientific and technical domains. To arrive at precise and trustworthy solutions, numerical algorithms for inverse problems must be designed and optimised. The creation and optimisation of numerical algorithms specifically created for solving inverse issues are presented in detail in this abstract.The formulation of inverse issues and the mathematical models that explain the underlying processes are the primary topics of the first part of this work. We examine many inverse issues, such as ill-posed, parameter estimation, and linear and nonlinear ones. Prior information and regularisation methods must be used to increase the stability and uniqueness of the answers.The creation and application of numerical algorithms for the solution of inverse problems is the focus of the second component. We study in depth a number of iterative techniques, including the conjugate gradient method, Levenberg-Marquardt algorithm, and Gauss-Newton method. There is also discussion of sophisticated methods such variational methods, Bayesian inference, and approaches based on optimisation.The third consideration focuses on optimising numerical techniques to raise their effectiveness and precision. To hasten convergence and lower computational costs, methods like adaptive mesh refinement, parallel processing, and model reduction are examined. Additionally, methods for handling noisy or missing data are looked at, as well as methods for choosing the right regularisation settings.
Analysis of Computational Algebra for Cryptography and Coding Theory Applications
Authors: Bhandari Ashok Singh
Published: June 2023

Secure communication is essential in many areas of today's interconnected society, from online commerce to international affairs. The foundation of data security is made up of encryption and decryption algorithms, and effective execution calls for an organised approach rather than a chance procedure. This study analyses several encryption techniques with an emphasis on those that apply algebraic coding theory to cryptography. These algebraic coding theory-based cryptographic systems are particularly significant for the future of data security because, in contrast to many existing systems, they provide resistance against attacks from quantum computers.This essay emphasises the necessity of an organised approach while outlining the essential concepts of encryption and decryption. It examines several encryption techniques, including symmetric and asymmetric encryption, pointing out their advantages and disadvantages.The study then explores how algebraic coding theory is used in cryptography. It explores the fundamental mathematical concepts that underlie algebraic coding methods, including finite fields and polynomial arithmetic. The McEliece cryptosystem and Niederreiter cryptosystem are two examples of unique algebraic coding theory-based cryptographic schemes that are the subject of this examination, which also highlights their benefits in terms of security and resilience to quantum assaults. These methods' computational complexity is also analysed, taking into account things like key sizes and encryption speed.With the help of the knowledge gleaned from this investigation, strong encryption systems that can survive upcoming developments in computing technology can be created, guaranteeing the secrecy and integrity of critical data in daily life.
Sustainable Construction Materials for Civil Engineering Projects
Authors: Bahuguna Anoop
Published: June 2023

Sustainable construction materials have gained significant attention in civil engineering projects due to their potential to reduce environmental impact and promote long-term sustainability. This abstract provides an overview of sustainable construction materials and their application in civil engineering projects. It highlights the importance of sustainable materials in mitigating climate change, reducing resource depletion, and improving overall environmental performance.

The incorporation of sustainable construction materials in civil engineering projects is crucial for achieving sustainability goals. Traditional construction materials, such as concrete and steel, have significant environmental drawbacks, including high carbon emissions, energy consumption, and depletion of natural resources. Sustainable materials offer viable alternatives that can address these challenges.
Structural Health Monitoring for Civil Engineering Infrastructure
Authors: Negi Ankit
Published: June 2023

Structural health monitoring (SHM) plays a vital role in ensuring the integrity, safety, and reliability of civil engineering infrastructure. With the increasing complexity and aging of structures, the need for effective monitoring systems has become paramount. This abstract presents an overview of the field of structural health monitoring, highlighting its significance in civil engineering and exploring various techniques and technologies used for monitoring the health of infrastructure.The objective of structural health monitoring is to detect, assess, and predict the condition of structures in real-time, enabling proactive maintenance and minimizing the risk of catastrophic failures. Traditional inspection methods, such as visual inspection, have limitations in terms of cost, accuracy, and coverage. SHM provides continuous and automated monitoring, enabling the collection of data from various sensors installed on the structure. These sensors capture data related to structural behaviour, environmental conditions, and loading conditions, among others.This abstract delves into the different types of sensors employed in SHM for civil engineering infrastructure. These sensors include strain gauges, accelerometers, displacement transducers, temperature sensors, and corrosion sensors. Strain gauges measure the strain or deformation experienced by the structure, while accelerometers detect vibrations and dynamic responses. Displacement transducers monitor the movement or displacement of specific points, providing valuable information about structural deformations. Temperature sensors help in understanding the effect of temperature variations on the structural behaviour. Corrosion sensors detect the presence of corrosion, a significant issue in infrastructure deterioration.
A Survey of Clustering Algorithms for High-Dimensional Data Mining
Authors: Kukreti Anil
Published: June 2023

The increasing complexity and dimensionality of data in numerous domains, including bioinformatics, text mining, multimedia, and social network analysis, pose significant challenges to traditional clustering algorithms. This paper provides a comprehensive review of various clustering algorithms suitable for high-dimensional data mining. We begin by elaborating on the challenges and difficulties intrinsic to high-dimensional spaces, such as the curse of dimensionality and the concentration of measure. Following that, we investigate a variety of different approaches to clustering, such as partitioning techniques, grid-based methods, hierarchical methods, density-based methods, and model-based methods. These algorithms are examined with a particular emphasis on how well they deal with high-dimensional data and how well they deal with data noise, as well as how well they can scale and how easily they can be interpreted. The most current developments in subspace and correlation clustering, as well as embedding approaches and the application of deep learning to the clustering of high-dimensional data, are also included in this overview. With the help of this in-depth analysis, our goals are to give insights into the benefits and drawbacks of each algorithm and to aid academics and practitioners in picking the optimal approach for the high-dimensional data mining projects they are working on.
A VARIANT FOR USING REGRESSION ANALYSIS TO ASSESS THE ELECTROMAGNETIC ENVIRONMENT IN AN URBAN AREA
Authors: Pulov Dimcho , Karadzhov Tsanko , Pulova-Ganeva Yuliya
Published: June 2023

The current study was conducted by making a series of experimental measurements of the electric field strength E.  The obtained results have been interpreted using the method of mathematical modelling because the object of study – electromagnetic environment (EME) is a multifactorial system. With the accepted limitation of considering the influence of only two factors (frequency and time intervals) a two-factor regression analysis was used. The processing of the obtained data was performed by two-dimensional quadratic objective function.
PRODUCT MARKET EXPANSION STRATEGY FOR BUSINESS DEVELOPMENT OF THE COMPANIES OPERATING IN THE FIELD OF PREMISES CLEANING
Authors: Zvirgzdina Rosita , Sakena Dace , Linina Iveta
Published: June 2023

The long-term strategic development of cleaning companies cannot be implemented by providing only one type of service - cleaning of premises.Within this research the author studied the theoretical aspects of corporate strategies, product market expansion strategy for business development of the cleaning companies, to understand the industry of cleaning of premises and challenges of that industry.A monographic and descriptive method was used to analyze the theoretical aspects of company strategies, secondary data analysis and expert interview were used to describe the situation of premises cleaning industry, but quantitative research method such as analyzing of statistical data of the cleaning of premises companies, in connection with the comparative, analytical, deductive, logical approach method was used in this research.The research identifies factors that the expansion of the range of services is relevant in every business and every industry, because every industry develops over time, new regulations are adopted that can affect the respective industry, which means that companies are constantly forced to adapt to changing business, economic and political conditions.The research finds that if the company has successfully developed, has found its market share, and is working with good results, this does not mean that the company can relax and not think about its development.
INFLUENCE OF INTERCROPPING ON SOIL MICROBIAL ACTIVITY AND STRAWBERRY DEVELOPMENT
Authors: Laugale Valda , Lepse Līga , Zeipiņa Solvita
Published: June 2023

Strawberry is one of the most important berry crop grown around the world and their consumption increases every year. The introduction of new practices promoting farm sustainability and long-term soil health in strawberry production systems is very essential. Towards environment- and climate-friendly farming practices intercropping can be used to improve soil microbiological activity and biodiversity, and reduce the use of pesticides and mineral fertilizers, while the right choice of intercropped plants is of great importance to achieve these goals. The trials on strawberry intercropping were established in Latvia in 2021. Three treatments with different intercropping plant rotations, including crimson clover, pea, garlic, marigold, and winter rye mix with vetch, were compared to conventional strawberry growing using straw mulch. Trial was installed in three locations: two organic farms and the Institute of Horticulture (LatHort). Thus representing climatically different regions and different soil conditions. Strawberries were grown in 1.2 m distant rows, where in the intercropping treatments, each second interrow was occupied by companion plants. Soil microbial activity was evaluated during vegetation seasons by determining soil respiration rate (SRR) and dehydrogenase activity (DHA) several times per season in 2021 and 2022. Strawberry vegetative development was evaluated at the end of each vegetation season. During the investigation period, soil microbial activity fluctuated during vegetation seasons, depending on growing conditions. In 2021, SRR varied from 1.9 – 3.3 CO2 mg L- 1, while in 2022, from 2.1 - 3.4 CO2 mg L-1. DHA varied from 46 – 134 INTF, µL×????−1 × h in 2021 and 60 – 101 INTF, µL×????−1 × h in 2022. Intercropping had low influence on microbial activity and results differed within each location. Strawberry plant biomass differed among locations and treatments with the highest above-ground biomass observed in LatHort during second growing season in conventional growing system (790 g plant-1).
AN APPROACH TO MODELING INNOVATION OBSOLESCENCE
Authors: Petrova Desislava Ivanova
Published: June 2023

Currently, the Fourth Industrial Revolution (FIR) has a very strong impact on innovation activity and innovation obsolescence. In order to formulate a methodology for the selection of alternative solutions, it is necessary not only to take into account the impacts of FIR, but also to choose an approach for modeling innovation obsolescence. The aim is to propose a new approach for modeling innovation obsolescence, in which the influencing factors will already be present in the innovation development methodology.
THE EFFECT OF AN INNOVATIVE FERTILIZER OF DIGESTATE AND WOOD ASH MIXTURES ON WINTER GARLIC PRODUCTIVITY
Authors: Adamovičs Aleksandrs , Poiša Liena
Published: June 2023

Garlic (Allium sativum L.) is a widespread crop in vegetable production. The popularity of garlic is due to its bactericidal and antioxidant properties. Digestate and wood ash are the by-products of cogeneration plants. The digestate is rich in nutrients, can provide a large part of the nutrients needed by the plant during the growing season, as well as improves the soil structure. Wood ash contains small amounts of phosphorus and potassium and is strongly alkaline (pH 8–12) due to the oxides in its composition, mostly calcium carbonate. The purpose of the study was to determine the effect of fertilizer rates of the digestate and wood ash mixtures on winter garlic productivity and harvest quality. Field trials with the winter garlic variety 'Lubaša' were established in sod clay, loamy soil. In the garlic plantation, different variants of fertilizer mixtures were used – they contained pig or cattle manure or plant residue digestate, and wood ash. The ratio of digestate and wood ash in the mixtures was 3:1; fertilizer rates for winter garlic were 15 and 30 t ha-1. In the study, the different types of fertilizers showed different effects on the yield and quality of winter garlic.
CHARACTERIZATION OF THE ZOOPLANKTON COMMUNITY OF A SHALLOW LAKE WITH ORGANIC-RICH SEDIMENT
Authors: Tretjakova Rasma , Brakovska Aija , Paidere Jana
Published: June 2023

In this research, the ecological quality of the lake Vēveru (Latvia, Rēzekne district) according to zooplankton was investigated. Lake Vēveru has a large sapropel deposit with rich reserves of sapropel. Removal of sapropel requires organization of spatio-temporal monitoring to control the state or disturbance of the existing ecosystems in the long term. Zooplankton samples were collected and analyzed using standard methods in the open pelagic and littoral zones of the lake in different seasons. Quantitative samples of zooplankton in each sampling site were collected from the surface water layer at the depth of 0.5 m by filtering 100 l of water through an Apstein-type plankton net (64 µ). Biodiversity of zooplankton taxa in Lake Vēveru shows that the food base of juvenile and planktophagous fish is sufficient. The Shannon index according to the diversity of zooplankton taxa ranges from 0.84 to 1.52 by abundance, from 1.52 to 2.21 by biomass.
ESTIMATION OF SALMONELLA SPP. PREVALENCE AND DIVERSITY AMONG FREE-LIVING TURTLES AND A ZOO COLLECTION
Authors: Umbraško Inta , Batjuka Anna , Petjukevičs Aleksandrs , Pupins Mihails , Škute Natalja
Published: June 2023

Salmonellosis infection is caused by bacteria of the genus Salmonella. There are many pathways for the pathogenic bacteria to spread which is through contaminated food, water, and contact with animals. The research was conducted to detect Salmonella spp. carriage in free-living aquatic turtles and zoo turtles. Turtles are frequent inhabitants of zoos and the owners of a large number of bacteria in their outer skin and shell surfaces that under adverse conditions can multiply and lead to the development of infection. However, they are known to be a frequent source of Salmonella infection without showing signs of disease. The risk of human infection exists if personal hygiene is not followed after contact with a turtle. Identification of bacteria of the genus Salmonella, the main causative agent of the disease was determined by the standard method on chromogenic Salmonella LAB-Agarᵀᴹ (BIOMAXIMA, Poland) agar. The inoculation was incubated under aerobic conditions at 37 ± 1°C for 72 h. Serotype (D serotype) was determined by serotyping in 11 from 16 (68.75%) Zoo inhabitants but not found in 25 free-living turtles. Our present research is of theoretical and practical value for the study of free-living turtles as well as from the collections of zoos under protection in Latvia and Europe. It is necessary to remember the possibility of infection with pathogenic bacteria.
MECHANICAL SYSTEM FOR WIRE ARC ADDITIVE MANUFACTURING
Authors: Petrov Krum , Tongov Evgeny
Published: June 2023

This article discusses the reassembly of a mechanical system for 3D printing plastic parts to be used for plasma arc additive manufacturing. The main issues in converting an existing 3D printer designed for plastic additive to used for producing metal parts are: control of the welding power source; installation and realization of the movement with the welding torch; set the height of the zero layer; setting up the program software to generate the control file.
PREREQUISITES FOR THE CREATION OF THE "FROM FARM TO SCHOOL" MODEL IN THE KLAIPEDA REGION: THE STUDY OF TARGET GROUPS’ EXPECTATIONS AND PERCEPTIONS
Authors: Melnikova Julija , Dailidienė Inga , Graigaliūnienė Simona , Stonkė Eglė
Published: June 2023

The focus of the article is on school meal programs that are common throughout the world and are implemented to promote students’ healthy eating habits and bring added value to their learning outcomes. In recent years there has been increasing emphasis on the possibility of improving school meals by including locally grown products, thus contributing to the development of local economic systems. This model has acquired the name "Farm to School" in practice of some countries and, according to its supporters, emphasizes public procurement of locally grown food as a key market opportunity for farmers. The article has been prepared within the BSR Food Coalition project (funded by Interreg Baltic Sea Region Program, contract #S002). The project seeks to create the conditions for the emergence of the "From farm to school" model in the Baltic States. The study presented in the article aims at disclosing the conditions and opportunities for the promotion and use of foods produced by local farmers in general education schools in Klaipeda region, Lithuania as well as at defining necessary educational efforts to increase healthy nutrition, develop general health habits, and agricultural and food system literacy within general education schools and their communities. To achieve the aim the surveys with project target groups (school administration, students and their parents) have been carried out in Klaipeda region. The objectives of the survey were to gather data on target groups’ perceptions of local school food procurement and to disclose their opinion, needs and expectations related to model development. The findings of the study would be helpful for designing the further steps of collaboration between schools and local farmers in Klaipeda region. .
RAPID PROTOTYPING OF PEAR DETECTION NEURAL NETWORK WITH YOLO ARCHITECTURE IN PHOTOGRAPHS
Authors: Kodors Sergejs , Sondors Marks , Lācis Gunārs , Rubauskis Edgars , Apeināns Ilmārs , Zarembo Imants
Published: June 2023

Fruit yield estimation and forecasting are essential processes for data-based decision-making in agribusiness to optimise fruit-growing and marketing operations. The yield forecasting is based on the application of historical data, which was collected in the result of periodic yield estimation. Meanwhile, the object detection methods and regression models are applied to calculate yield per tree. The application of powerful neural network architectures for rapid prototyping is a common approach of modern artificial intelligence engineering. Meanwhile, the most popular object detection solution is YOLO architecture. Our project team collected the dataset of fruiting pear tree photographs (Pear640) and trained YOLOv5m with mAP@0.5 95% and mAP@0.5:0.95 56%. The obtained results were compared with other YOLOv5-7.0 and YOLOv7 models and similar studies.
GENETIC DIVERSITY AND POPULATION STRUCTURE OF THE EUROPEAN EEL (ANGUILLA ANGUILLA) IN BALTIC LAKELAND
Authors: Oreha Jelena , Morozova Aleksandra , Garkajs Alberts , Kirjušina Muza , Škute Nataļja
Published: June 2023

Anguilla anguilla (Linnaeus, 1758) is the unique catadromous fish species in the Latvian fauna. The Baltic Lakeland area representing naturally recruited and introduced eels. In recent decades, its population has decreased not only in Latvia, but also in Europe. European eel critically endangered due to overfishing of glass eels, blocking of migratory paths, deaths in HPS turbines, water pollution and diseases and parasites. Only some bodies of water are freely accessible to natural migration of eels in Latvia.Currently, its position has been recognized as being critical, and a range of normative acts have been adopted for its restoration, such as the Regulation EC 1100/2007. The restocking programs of the European eel Anguilla anguilla have been conducted for nearly one century in Latvia.This study provides the first data on population structure of freshwater eels in Baltic Lakeland, for use in eel conservation and management of aquaculture on a regional and/or global scale. By analysing the sequences of the Cyt b gene of mtDNA for individuals caught in locations throughout in Baltic Lakeland, we determined the population genetic structure of A. anguilla in the area. The diversity of haplotypes was studied in ten waterbodies from part of Baltic Lakeland, namely Lake Sīvers, Lake Usmas, Lake Ķišezers, Lake Liepājas, Lake Alūksnes, Lake Rāznas, Lake Vialikija Švakšty, Lake Svir, Lake Myadzyel, Myadzelka river. Additionally, this study investigated the affinity of the Latvian populations to other A. anguilla populations around the world.This is the first report about eel’s population genetic diversity in Baltic Lakeland. Haplotype variation was different in all investigated waterbodies. In current studies seven new unique haplotypes were detected. Eel population in Baltic Lakeland shows quite high genetic diversity and rapid population expansions, which possibly is results of intensive restocking program. Sequences characterized Anguilla rostrata in Lake Alūksnes were detected.
WETLAND CHANGE DETECTION USING SENTINEL-2 IN THE PART OF LATVIA
Authors: Skromulis Andris , Breidaks Juris , Puķītis Mārtiņš
Published: June 2023

In the article, the possible impact of changes on wetland were analysed by the semi-supervised classification method of statistical analysis. The Sentinel-2 raw data between two different seasons are combined together. The data preparation is shortly described in the article. Data is clustered with unsupervised method. The article describes a supervised method – how data credibility and classification can be estimated if its reference is poor quality.
ASSESSMENT BY MACROINVERTEBRATES OF THE ECOLOGICAL QUALITY OF SHALLOW LAKE WITH RICH SAPROPEL SEDIMENTS
Authors: Tretjakova Rasma , Paidere Jana , Brakovska Aija
Published: June 2023

In this research, the ecological quality of the Lake Vēveru (Latvia, Rēzekne district) according to macroinvertebrates was investigated. The Lake Vēveru has a large sapropel deposit. The Lake Vēveru is relatively little affected by human economic activity, the only moderate impact is sapropel mining in the lake in 2009-2012, it is planned to resume industrial sapropel mining in the lake. During the period of sapropel removal, a decrease in the transparency of water is noted due to the nutrient flow into the water mass, pH increases, the habitat of planktonic and benthic organisms is disturbed. Macroinvertebrates samples were collected and analyzed using standard methods in the open pelagic and littoral zones of the lake in different seasons. The ecological quality of the lake was assessed in accordance with the requirements of the European Water Framework Directive in Latvia. To characterize the ecological status of the lake the Latvian Lake Macroinvertebrate Multimetric Index was used. According to the Ecological Quality Ratio (EQR) the lake indicates a good ecological status of the water. However, a moderately low species diversity index indicates the dominance of certain taxa. In general, macroinvertebrates species that are often and widely found in Latvia and are environmentally tolerant have been found in the lake. Water temperature, pH, conductivity, dissolved oxygen, oxidation reduction potential, chlorophyll-α were measured with a HACH OTT DS5 Probe. Water transparency was measured using a Secchi disc.
SOME WI-FI ACCESS POINTS IN THE CITY OF SOFIA
Authors: Kolev Kaloyan , Shterev Yordan
Published: June 2023

The purpose of this article is to present the results of a study of the number and type of Wi-Fi access points using applications for the collection, processing and analysis of data based on a sample collected in different areas and places with a significant concentration of people in a city Sofia, Bulgaria. Data on the number and type of access points were obtained by measurements taken at the respective locations. User equipment connects to different Wi-Fi access points located in different places in the city that are accessible. Data was collected for wireless access points that are fourth and fifth generation. Different generations in wireless networks have corresponding download and upload speeds and frequencies. In the article, the results are grouped and analyzed according to different characteristics.
LIFELONG LEARNING FOR TALENT MANAGEMENT AND PROFESSIONAL DEVELOPMENT OF EMPLOYEES
Authors: Ochoa Siguencia Luis , Gródek-Szostak Zofia , Niemczyk Agata , Szeląg-Sikora Anna , Pagan Castano Esther
Published: June 2023

The new challenges in almost all organisations are based on people. It is their competences, knowledge and skills that enable any organisation to grow. Personnel are a resource that must be properly taken care of. Effective talent management is mainly based on planning and building career paths. Talent management is one of the most important business priorities for organisations that care about achieving business goals, knowledge management and managing staff potential. Research shows that entities that identify and manage talent produce 15 per cent higher results for their stakeholders compared to pillars that do not run such programmes.The aim of this article is to present the activities carried out within the framework of TALENT MANAGEMENT ERASMUS+ project nr 2021-2-ES01-KA210-ADU-000048687, which is dedicated to economically active employees over 45 years of age and promotes integration in the labour market.
FORMATION OF THE KNOWLEDGE BASE OF DIGITAL LIBRARIES BASED ON SEMANTIC MODELS OF AUTHORITY FILES
Authors: Urinkulov Odiljon Naziraliyevich , Rakhmatullaev Marat , Ziyodullayeva Gulchiroy Erkinovna
Published: June 2023

This article is devoted to the analysis of methods for creating a knowledge base of a digital library based on the semantic model of authority files. The article also describes the practical aspects of creating an electronic library legal encyclopedia based on the semantic model of authority files. Creation of a semantic network of authority files significantly optimizes the quality and speed of searching for resources in electronic libraries and creates the basis for intellectualization of information retrieval. The article examines in detail the existing approaches to creating a knowledge base of authority files, including files based on semantic models, and forming a knowledge base structure. The main purpose of the study is to create an improved model and develop software for creating a knowledge base of an electronic library of semantic authority files for various subject areas. In the article the theoretical research methods (method of comparison and critical thinking) and empirical research methods (data collection and document analysis) have been applied. Used object-oriented programming, intelligent information retrieval, reverse indexing capabilities. The field of jurisprudence was chosen for the application and approbation of the created model and software. A knowledge base has been created that studies frequently used specialized terms and semantic relationships between them.
WHY T-SHAPED ENGINEERS IN THE MINING SECTOR ARE VITAL FOR PROGRESS.
Authors: Robam Karin , Hand Tony , Karu Veiko
Published: June 2023

The importance of minerals and metals in the development of technologies vital for modern society to function and for increasing clean energy needs, cannot be understated. However, what is the level of knowledge of people working in this field, and how can we be sure that these people also update their knowledge continuously? There is a growing need for educated employees and engineers with a knowledge of wider issues associated with the mining sector. To align the competence of university graduates and employees with what is required in the labour market, it is necessary to develop a vocational system that identifies the competence of these mining-related occupations and incorporate new systems and ways of thinking, particularly in sustainability issues. Professional standards create opportunities for assessing competence. An occupational qualification standard describes the relevant occupational activity and competence necessary for practicing an occupation, i.e., skills, knowledge, and attitudes. When challenging work needs to be done, engineers with a deeper knowledge are needed, this is where the T-shaped professional comes in. The requirement for flexible and adaptable current and future employees is vital for the extractive sector and all the downstream industries that rely on raw materials to produce the goods and services that keep society moving. This article examines the importance of the T-shaped professional in the mining industry.
USING COMMUNICATION AND COLLABORATION TOOLS IN VIRTUAL LEARNING ENVIRONMENTS MOODLE FOR MATHEMATICS IN PRIMARY SCHOOL
Authors: Kondratavičienė Renata
Published: June 2023

With the advancement of information and communication technologies, teaching mathematics in a real-life classroom is combined with teaching in a virtual learning environment (VLE). It is important to determine how a primary school teacher can use VLE communication and collaboration tools to teach mathematics primary school students. Participants – 4th grade students ((n = 51). Access to quantitative studies has been chosen for the study. Methods of study: Analysis of scientific literature, testing, descriptive statistics, and inference statistics. Data from the pilot study and the educational experiment were processed using version 23 of the IBM SPSS Statistical Package for Social Sciences. The normality of the variable distribution was tested using the Shapiro-Wilk test. Throughout the research, decisions are taken at a value a = 0.05. Study adhered to the fundamental principles of the European Code of Conduct for Study Ethics. The curator of the education was in contact with the students and their parents by e-mail and using the VLE communication and collaboration tools (messages, forums, feedback). The aim was to find out whether the number of emails and messages sent by the curator affected the students’ learning time in the VLE. The hypothesis of zero Pearson coefficient equality in the population is checked. There was a statistically significant weak relationship between the number of emails sent by the curator of the curriculum, the number of messages for students and the time spent by the student for the lessons of the curriculum. There was a mean relationship in the boy’s group, but there was no statistically significant relationship in girls’ group. There was also a statistically significant weak relationship between e-mails sent by the curriculum curator, the number of messages sent to students and the evaluation of the lessons of the curriculum. There was an average relationship in the boy’s group, but in the girl’s group there was no statistically significant relationship between the emails sent by the tutor, the number of messages to students and the evaluation of the lessons of the curriculum. This confirms the theory of constructivism that VLE is suitable for education because teachers can act as learning facilitators to communicate with each other during learning.
AN REVIEW OF THE EFFECTIVE ENERGY CONSUMPTION WITHIN THE GREEN IT AND GREEN ENERGY STRATEGIES
Authors: Mamchur Dmytro , Peksa Janis
Published: June 2023

The paper provides analysis on the current state of the art in the field of green technologies, including green information technologies, and methods aimed to achieve effective energy consumption goals. Recent advances in the field summarized in prospective publications, were analysed. Modern Green IT and Green Energy strategies, aimed to reduce power consumption, environmental influence and improve sustainability, which assume the use of Cloud Technologies, renewable energy sources, proper recycling and reuse of devices and resources, were singled out. Finally, recommendations for IT and industrial companies aimed helping to achieve green strategies’ goals, were formulated.
INVESTIGATING THE POSSIBILITY OF ALLOYING AN ALLOY ALSI25CU5CR WITH CO, CR AND MO USING METAL POWDER
Authors: Dochev Boyan , Dimova Desislava , Panov Ivan
Published: June 2023

A base aluminium-silicon alloy AlSi25Cu5Cr was used to investigate the possibility of alloying aluminium alloys with hard-to-melt elements. The alloying elements Co, Cr and Mo were introduced into the melt using metal powder from a hard-melting dental cobalt-chromium-molybdenum alloy. The metal powder was packed in aluminium foil and introduced into the melt of the studied alloy at a temperature of 810º C. After alloying and mechanical stirring of the melt, it stood for 30 min. at a temperature, raised to 850º C and experimental castings were cast from it. After spectral analysis, the degree of absorption of the alloying elements by the aluminium melt was determined. The structure and mechanical properties of the thus obtained alloy were investigated.
DEVELOPMENT OF A METHOD FOR CONTACTLESS TEMPERATURE MEASUREMENT IN 3 SPECTRAL RANGES
Authors: Pulov Dimcho , Karadzhov Tsanko
Published: June 2023

A 3-spectral method for non-contact temperature measurement has been developed. Three silicon photodiodes were used. The separation of the spectrum is done by optical bandpass filters and beamspliters. It is possible to work in three modes: three-spectral, two-spectral (spectral ratio) and one-spectral. In the first mode, the temperature of objects with an unknown and variable emissivity can be measured. The last two modes give good results respectively for gray bodies and for objects with known emissivity.
A GEOMETRICAL SYNTHESIS OF COMEZ TEXTILE MECHANISMS OF FINALLY REMOVED POSSIBILITIES
Authors: Marinov Marin Jordanov
Published: June 2023

A synthesis of the COMEZ spatial knitting mechanism has been developed to convert rotational motion around a moving axle in a reciprocating motion. The synthesis has been done in extremely remote positions. For practical application of the synthesis, a vector-matrix approach is proposed in Math LAB Watt programming environment. With the specific metric parameters of the head mechanism, the function definition of the position is considered and a proposed eight-pointed mechanism replacing the spatial hump of the knitting head is proposed. To establish the authenticity of synthesis is an example.
EXPERIMENTAL STUDIES OF AN ALGORITHM FOR MINIMIZING THE IDLE TOOL MOVES WHEN MILLING COMPLEX SURFACES ON TRIAXIAL CNC MACHINE TOOLS
Authors: Salapateva Silviya , Stefanov Bano
Published: June 2023

The idle running times of the working units of a machine tool are the sum of the idle running times for the tool change and for changing the section uder treatment. The time, spent on idle running is the extra machining time. A large number of milling cutters are used for purely mechanical machining of details with complex surfaces and for a significant number of machined sections, where the complex surface is broken as a rule. This leads to an increase in the extra time for treatment. Reducing the auxiliary time in machining the parts will significantly increase the productivity of the actual milling process. When modeling the process of machining details with complex surfaces on triaxial milling machines, the optimization of the sequence of moves will allow to reduce the idle running time by up to 50% without causing deterioration in the quality of the surface layer. In modern production a method is needed, which would allow to automatically and quickly enough make a choice of an optimal option for a sequence of performing tool moves while taking into account the durability of the metal cutting tool.
MODIFICATION OF 5083 ALUMINUM ALLOY WITH GRAPHENE VIA FRICTION STIR PROCESSING
Authors: Zaekova Radostina , Tashev Plamen , Hadjitodorov Yasen , Gradinarov Deyan
Published: June 2023

Graphene-modified layer is obtained on 5083 aluminum alloy sheet material via friction stir processing. A special groove is cut in the aluminum plate and filled with graphene. The processing is carried out using an innovative technology with an appropriate tool. The temperature at a chosen point in the heat affected zone is measured in real-time by a remote-control system. Test specimens were prepared from the processed plates and metallographic analysis was carried out. The microhardness of the modified layer is measured perpendicular to the direction of processing and in depth. An increase in microhardness relative to that of the base material is found.
INFLUENCE OF NI AS MINORITY ALLOYING ELEMENT ON THE CORROSION BEHAVIOR OF AMORPHOUS AL-CU-MG ALLOYS IN CHLORIDE SOLUTION
Authors: Dyakova Vanya , Kostova Yoanna , Spasova Hristina
Published: June 2023

The influence of nickel as minority alloying element on the corrosion behavior of amorphous alloys (Al74Cu16Mg10)99Ni, (Al74Cu16Mg10)98Ni2 and (Al74Cu16Mg10)97Ni3 was investigated. The amorphous alloys were obtained as ribbons by Chill Block Melt Spinning (CBMS). The amorphous structure of the alloys was proven by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The corrosion rate was calculated gravimetric using continuous immersion tests for 360 hours in 3.5% NaCl solution at a temperature of 25oC. The lowest corrosion rate was found in the alloy containing 3 at. % Ni. The chemical composition of the accumulated corrosion products was studied using XRD.The influence of nickel on the local corrosion resistance of the amorphous ribbons of (Al74Cu16Mg10)100-хNiх x = 0, 1, 2, 3% alloys was investigated electrochemically in a solution of 3.5% NaCl at 25°C. Pitting potential (Epitt) and repassivation potential (Erp) were determined. It was found that most resistant to pitting corrosion was the (Al74Cu16Mg10)97Ni3 alloy, which showed the noblest pitting potential (Epitt -0.332 V) and repassivation potential (Erp -0.530 V).All obtained corrosion test results of the nickel-containing amorphous alloys were compared to the base amorphous Al74Cu16Mg10 alloy.