Science. Business. Society.
Vol. 10 (2025), Issue 2

Table of Contents

  • SCIENCE

    • Performance study of an algorithm for processing a packet of reflected ultrashort pulses under a priori unknown waveform and gaussian noise conditions

      pg(s) 34-35

      In this study, an analysis of the results obtained after simulation studies of the synthesized modified algorithm with a priori unknown form of the ultrashort pulses (USPs) reflected from a point target, and when operating in Gaussian noise conditions, has been carried out. Proposals for the boundary conditions for the optimal operation of the algorithm have been made. The Prony method has been used to determine the moment of arrival of the reflected signal and estimate the complex components of the USP amplitude. The study is a continuation of the publication devoted to the synthesis of a modified algorithm for processing a bunch of USP pulses reflected from a oint
      target.

    • Features of connecting a fuel cell stack to the three-phase load

      pg(s) 36-38

      In this study, a comparison of methods for connecting a fuel cell stack to a three-phase load was researched. The stack connection via a current source inverter and a voltage source inverter was considered. The study was conducted using simulation modelling in the MatLab/Simulink software. Simulation models of the operation of a fuel cell stack on a three-phase active-inductive load through a current source inverter and a voltage source inverter were created. The harmonic composition of the stack voltage, stack current, and load phase-to-ground voltage curves was studied. Losses in semiconductor converters and inductances were estimated. The influence of the switching frequency of semiconductors on losses in the current source inverter and voltage source inverter was studied.

    • Polymer composite materials modified with fillers from natural mineral rocks and some of their characteristic properties

      pg(s) 39-40

      One of the promising areas of modern chemical science is the production of polymer composite materials modified with fillers of various compositions, as well as testing and quality control of such products. Based on this trend, scientific research was conducted to obtain composite materials filled with fillers with a number of excellent properties. Thus, composites containing natural mineral rocks and polyolefins characteristic of the Karabakh region were obtained with different ratios of components and their properties were studied. In addition, the article prepares and presents an overview of a number of scientific studies conducted in this direction. The use of fillers with such compositions as modifiers makes research simple and accessible, since they are environmentally friendly and safe, have low financial costs for purchase and acquisition, and also have a high probability of obtaining a higher quality product. The resulting polymer is obtained in a relatively simple way. Natural mineral fillers are mined in a number of the most beautiful places in our country.

    • The properties of carbon plastics modified with polyphenylmethylsiloxane

      pg(s) 41-43

      The article presents a technology of carbon plastics producing based on polyamide-6 with the incorporation of PMS-400 grade lubricant into the material structure. A brief review of the results of carbon plastic applications in engineering is provided. The research methodology and initial parameters are outlined. The experiments were carried out using a single-screw extruder EKG-45, modernized to produce the carbon plastics. As the object of the study, a laboratory-produced carbon plastic СPA-6-20 was used. This material is a carbon plastic based on polyamide-6 reinforced with 20 wt.% carbon fiber. Experimental results established that the optimal screw rotation speed of the EKG-45 extruder is 90 min⁻ ¹. Under this processing mode, the compressive yield stress increased by 4%, while the impact toughness rose by 4.5%. At this stage of the research, mechanical strength properties were considered, as the most critical for applications in heavily loaded components of moving joints. The investigations carried out at the Dnipro State Agrarian and Economic University.

  • BUSINESS

    • Irrigation regime and its impact on the yield of greenhouse tomatoes using an ecological and water-saving irrigation technique, for the Plovdiv region

      pg(s) 44-46

      A study was conducted to determine the irrigation regime and its impact on the yield of three genotypes of greenhouse tomatoes in 2022 at the experimental field of MVCRI – Plovdiv in an unheated steel-glass greenhouse of the Venlo type. The experiment was conducted in three irrigation regimes:
      Optimal 100%M, reduced by 25% and increased by 25%, using water-saving technology.
      The size of the irrigation norms, the number of irrigations for the growing season and their distribution by development phases for the soil and climatic conditions of the Plovdiv region were determined.
      The obtained results for irrigation of greenhouse tomatoes show that 18 irrigations were implemented during the growing season in order to maintain soil moisture between 85-100% of the maximum field moisture capacity for the conditions of Plovdiv from the beginning of May to the end of July.
      The size of the irrigation rates by regimes varies from 14.9 to 24.7 mm, and the irrigation rates – from 268 to 447 mm. The maximum irrigation rates during the period with the most significant water consumption can be applied after 3-4 days and satisfy the needs of the plants. The analyzed results of the yields obtained from the three tomato genotypes at different irrigation rates show that the highest total yield of greenhouse tomatoes is formed in the variant with 125% implementation of the irrigation rate, followed by the variant with 100% irrigation rate, and the lowest, in the variant with 25% reduction in the irrigation rate.
      Obtaining a good effect from irrigation and the most productive use of irrigation water is possible only when applying an optimal irrigation regime, consistent with the requirements of the crops grown.
      A number of studies have been conducted in our country on the limiting factor – water. Their main goal is to establish the best efficiency of applying different irrigation regimes for irrigation under optimal and insufficient water supply. (Kireva et al 2020)
      The best results in terms of water use in this crop are obtained when the soil moisture is above 85% of the WHC and is applied to water-saving irrigation techniques. This method fully meets the requirements for sustainable agriculture and ecological fruit production, including ensuring high yields and quality of production, reducing unwanted side effects. (Bucks et al.,1982; Kireva ,2020.)
      The results obtained by (Mukherjee, S., et al. 2023) show that physiological characteristics, yield and water productivity are significantly influenced by the irrigation system and soil moisture regime, with drip irrigation improving the average yield of tomatoes by 25%.
      It was found that reducing the optimal rate (100% M) with a water stress of 50% (50%M), a significant decrease in yield (13.16%) was observed in greenhouse tomatoes (Wu et al. 2022 ; Lu et al. 2019 ). Alternatively, Wu et al. ( 2022 ) stated that under optimal irrigation conditions, tomato plants produced more fruits than those grown under deficit irrigation.
      With the studies of the mutual influence of different irrigation regimes on the yield of tomatoes grown in a polyethylene unheated greenhouse, it was found that the impact of irrigation on yield has a greater effect at higher levels of irrigation rate, (Stoyanova A. et al.,2020; Stoyanova A. et al. 2019).
      Studies of the irrigation regime and its influence on the yields of tomatoes grown in plastic greenhouses using drip irrigation are quite scarce, and the studies carried out in our country are for the conditions of the Sofia Field (Aboamera M. 1992; Kireva,; Kireva R.,2020) and for St. Zagora (Stoyanova An. et al. , 2020), which cannot be indicative of other agro-climatic regions of the country, which are characterized by different soil and meteorological conditions. Given the above, it is evident that research is needed to establish the complex influence of the irrigation regime on the quantity and quality of the yield of tomatoes grown in glass unheated greenhouses for the soil and climatic conditions of a region with developed vegetable production, such as Plovdiv. This will be achieved by using principal component analysis to assess the effects of tomato quality and the efficiency of water use and fertilization.
      Study objective – determining the irrigation regime and its influence on the yields of greenhouse tomatoes for the region of the city of Plovdiv

  • SOCIETY

    • Global Best Practices and Recommendations for Assessing and Improving Cybersecurity by Applying Intrusion Detection / Prevention System Selection Metrics

      pg(s) 47-49

      This article proposes an approach to improving the use of IDS/IPS systems in computer networks of forces and means of state and local administration bodies in the event of incidents, disasters, accidents and catastrophes. To this end, good practices for selecting an appropriate type of IDPS to increase the level of cybersecurity in the organization are studied. It is proposed to use the “type” metric to develop a comparative analysis of the correspondence between the types of IDPS and their ability to protect against ransomware, using the classification of tactics and techniques in accordance with the MITRE ATT&CK framework.

    • The importance of the economic and social dimension of the public sector in the Republic of N. Macedonia for employee motivation and job satisfaction

      pg(s) 50-52

      Work in the public sector reflects democratic, economic, and social values as a whole. All institutions share the responsibility to deliver better value for citizens and businesses, thereby ensuring appropriate and meaningful sustainable economic and social development – i.e., prosperity for the Republic of N. Macedonia overall. For these reasons, this paper aims to define, establish, and highlight the importance of the public sector’s economic and social dimension, and to examine how, in both of its forms, that dimension affects motivation and job satisfaction among public-sector employees in the Republic of N. Macedonia.

    • A Data-Driven Perspective on Demographic Changes in Veliko Tarnovo (1878–2024) Using Power BI

      pg(s) 53-56

      This study presents a data-driven exploration of the demographic evolution of Veliko Tarnovo from 1878 to 2024. By compiling population data from official census records and statistical yearbooks, the project builds a unified dataset covering nearly 150 years of urban development. The analysis focuses on population dynamics by gender and total population growth, identifying key periods of expansion and decline. The visualizations were developed using Power BI, providing an interactive and intuitive dashboard that enables users to explore trends, compare periods, and observe long-term demographic shifts. The study highlights a sharp population increase during the socialist era (1950s–1980s), followed by a significant decline in the post-1990 period, interpreted in the context of socioeconomic transformations and migration processes. The research offers both historical insight and a modern methodological approach, demonstrating how business intelligence tools can be effectively applied in urban demographic analysis and digital heritage projects.

    • Ecological sustainability in written heritage preservation practices: contemporary approaches and challenges

      pg(s) 57-59

      In the context of global environmental changes and the need for sustainable cultural policies, the preservation of written heritage is taking on a new dimension – combining effective conservation with a commitment to the environment. This report examines the principles of environmental sustainability in contemporary practices for the conservation and restoration of written collections, focusing on the application of so-called “green” methodologies – biodegradable materials, enzymatic solutions, anoxic disinfection, as well as energyefficient technologies in repositories. Special attention is paid to the concept of “green heritage”, understood not only as conservation with a minimal carbon footprint, but also as a strategic model for the long-term management of cultural resources. Examples from international practice that integrate sustainable solutions are analyzed. The report also highlights the challenges associated with the shortage of environmentally friendly materials, the need for a transdisciplinary approach and the need for educational policies aimed at building cultural and environmental sensitivity among specialists and the general public. In conclusion, the thesis is advocated that ecological sustainability is not an additional aspect, but an indispensable part of a new ethic in the preservation of written heritage – an ethic of respect for the past and responsibility for the future with care for the planet.
      The report is under project No. KП-06-H90/6 dated 10.12.2024 on the topic: “Ecologically sustainable conservation strategy for written heritage” from the Scientific Research Fund, Competition for funding of fundamental scientific research – 2024. Supervised by Chief Asst. PhD Eng. Iskra Tsvetanska.

    • Analysis of Using of Solar Energies in Georgia

      pg(s) 60-67

      The main sources of green energy (GE) as the cleanest form of energy or types of renewable energy sources (RES) are: wind, water, sun and earth. And solar energy (SE), which originates from the Sun, is one of the cleanest and most efficient renewable energy sources (RES). While the world, especially in the most developed countries of the world, has advanced far in the application of various forms of green energy (GE), in Georgia this field is in its infancy and it is not possible to predict when the first major positive developments in this field will be made. The paper presents a trend analysis and examples of the use of solar energy (SE) in Georgia currently and with a forecast until 2030. According to the data on the plans of the state authorities (Ministry of Economy and Ministry of Energy of Georgia), the development and use of solar energy (SE) with a plan of 250 MW for 2025 will increase according to the forecast for 2030 to 810 MW, with a CAGR value of 26,51 [%] and to 1330 [MW] in 2040, with a CAGR index of 11,79 [%] for that period. (or app. 5.32 times today’s value). The paper also presents several examples of the use of solar energy (SE) in Georgia in various areas of application.