South-West University "Neofit Rilski"

The increasing demands on software development are putting serious pressure on its pace. To assist software developers, an increasing number of tools powered by generative artificial intelligence are being introduced. This paper aims to investigate how the use and integration of generative AI have evolved among professionals in the software industry, based on a study involving 104 individuals working in Bulgarian software companies. Data was collected in April 2024 through an online questionnaire with four separate groups of questions related to the use of generative AI at work. The study found that 2/3 of the respondents use generative AI actively in their daily work. They highly value the practical benefits of this type of technology, which most often consist of automating routine activities, accessing information quickly, generating initial code, and writing documentation. As a result of these benefits, developers are increasingly moving towards using generative AI at the expense of professional support platforms. The main benefits they cite include faster solutions, more specific and relevant answers, and significantly shorter time to reach the desired outcome.

In this paper, we study local and nonlocal problems of conformable semilinear evolution inclusions with causal operators, which include time lag system and a large classes of parabolic multivalued differential equations. We first investigate the problems with the help of measure of noncompactness and afterwards when the right-hand side is Lipschitz.

In this paper, we consider endomorphisms of an undirected cycle graph from Semigroup Theory perspective. Our main aim is to present a process to determine sets of generators with minimal cardinality for the monoids wEnd C n and End C n of all weak endomorphisms and all endomorphisms of an undirected cycle graph C n with n vertices. We also describe Green’s relations and regularity of these monoids and calculate their cardinalities.

In this paper, we consider partial differential equations (PDE) of parabolic type with functional nonlinearity in the reaction summand. Our goal is to give the answer of the question if there exist a set of smooth functions satisfying the inequality [Formula: see text], where [Formula: see text] is a parabolic operator in the parabolic PDE with a functional nonlinearity. To this end, we use some modification of the implicit function theorem. Finally, we give an example illustrating the theory.

This paper aims to explore the economic effects of the COVID-19 pandemic and the war in Ukraine on the twenty-seven European Union (EU) member states, known as the EU-27. A vector autoregression (VAR) of quarterly data for the period 2020-2022 was employed to study the impact of the coronavirus and the Russian invasion of Ukraine on growth, unemployment and inflation in the EU-27. The results from the empirical analysis indicated that the war in Ukraine lowered growth and raised inflation and unemployment, while the COVID-19 pandemic did not affect growth, increased unemployment and decreased inflation in the EU-27. It may be concluded that the war in Ukraine shifted the EU aggregate supply curve to the left, whereas the coronavirus pandemic resulted in inflation-unemployment trade-off in the EU.

This paper examines the use of modern information technologies in Bulgarian pre-school and primary education, focusing on teachers' knowledge and use of technologies and the challenges they face. The study is based on an extensive literature review, which highlights the potential of modern information technologies such as programmable devices, virtual reality (VR) and augmented reality (AR) to improve the quality of education, student engagement and continuous learning. However, the research also identifies persistent barriers to their implementation, including insufficient resources, limited training opportunities and teacher resistance to technological change. The main objective of the study is to assess the level of knowledge and use of technologies among Bulgarian teachers, with a focus on identifying the main barriers to their effective integration into educational practice. The preliminary hypothesis suggests that despite the recognition of the potential benefits of technologies, their use remains limited due to institutional and personal factors. Methodologically, the study used a descriptive survey approach with 205 participants, including pre-school and primary school teachers, principals and education administrators. Data was collected using an online survey platform included in Microsoft Office 365. Key findings show varying levels of knowledge and use of modern technologies among teachers. Although a significant proportion of respondents use technology in their teaching, the level of adoption of more advanced technologies such as programmable devices, VR and AR is significantly lower. Teachers expressed a strong desire for additional information and training on modern technologies, highlighting their potential to enrich learning experiences in a variety of subjects. The study has important implications for the Bulgarian education system. It highlights the gap between the recognised potential of technologies and their practical application in the classroom. Addressing the identified barriers through targeted investment in resources, comprehensive professional development programmes and ongoing support for teachers is crucial. By overcoming these barriers, educational institutions can better prepare students for the challenges of the digital age, improve learning outcomes and create a more dynamic and effective educational environment.

Here, we demonstrate the implementation of transparent conductive aluminum-doped zinc oxide (AZO) thin films deposited on glass substrate (AZO/glass) by the atomic layer deposition technique in liquid crystal (LC) spatial light modulator (SLM) devices. Structural, optical, and electrical properties as well as surface free energy reveal the high quality and uniformity of deposited AZO layers. We present two types of structures that highlight the multifunctional role of AZO thin films in SLM configurations: (i) as a transparent conductive layer for assembling regular antiparallel LC cells and (ii) as a transparent conductive layer and alignment layer allowing vertical alignment in LC display devices. A comparison of the electro-optical parameters such as pre-tilt angle, phase modulation, driving voltage, and response time of both devices is presented and discussed. AZO thin films prove superior performance, indicating a growing demand for the next generation indium tin oxide-free technology, including advanced display devices and dynamic flat-panel functionalities.

We argue that the importance of family relationships for individual well-being varies across societies as a function of a society’s degree of cultural heterogeneity. To examine the role of family relationships, we analyzed the responses from 13,009 participants in 50 societies on their life satisfaction across societies varying in their levels of historical and contemporary cultural heterogeneity. Such heterogeneity creates differences in the frequency of interacting with unfamiliar groups, which leads families to become more central to their members’ satisfaction with life. Multi-level analyses showed that historical and contemporary cultural heterogeneity moderated the pattern such that greater historical or contemporary cultural heterogeneity of society promoted a stronger positive relation between family relationship satisfaction and individual life satisfaction. Our results also revealed that the moderating role of historical cultural heterogeneity was more reliable than that of contemporary cultural heterogeneity. These findings demonstrate the importance of societal demography in shaping people’s psychological processes in different historical periods, suggesting a universal, trans-historical cultural process.

We report a two-step growth process of MoS2 nanoflakes using a low-pressure chemical vapor deposition technique. In the first step, a MoS2 layer was synthesized on a c-plane sapphire substrate. This layer was subsequently re-evaporated at a higher temperature to form mono- or few-layer MoS2 flakes. As a result, the close proximity re-evaporation enabled the growth of pristine MoS2 nanoflakes. Atomic force microscopy analysis confirmed the synthesis of nanoclusters/nanoflakes with lateral dimensions of over 10 μm and a flake height of approximately 1.3 nm, demonstrating bi-layer MoS2, whereas transmission electron microscopy analysis revealed triangular MoS2 nanoflakes, with a diffraction pattern proving the presence of single crystalline hexagonal MoS2. Raman data revealed the typical modes of high-quality MoS2 nanoflakes. Finally, we presented the photocurrent dependence of a MoS2-based photoresist under illumination with light-emitting diode of 405 nm wavelength. The measured current–voltage dependence across various luminous flux outlined the sensitivity of MoS2 to polarized light and thus opens further opportunities for applications in high-performance photodetectors with polarization sensitivity.

The digital transformation of healthcare, education, industry, and agriculture has generated new opportunities but also led to an increased use of digital devices that will lead to an increase in electronic waste (e-waste) at the end of the life cycle of these devices. In this paper, we report the electromagnetic properties of plant leaves from ten of the most used flowers that can be used to produce environmentally friendly microstrip antennas or fully biodegradable sensors for application in smart agriculture. The analysis of the results for the electromagnetic properties of the leaves of selected plants showed that the real part of the relative permittivity varied widely from 22.962 to 67.43387 for the leaves of garden plants and from 27.82699 to 55.80639 for the potted plants. The variation of the loss tangent of leaves is quite similar in potted (from 0.22718 to 0.35972) and garden (from 0.22812 to 0.33277) flowers.

This article examines the intricacies of European integration for Western Balkan countries, exploring the unique challenges each state confronts on its path to EU membership. It delves into the political, legal, and diplomatic reforms required, emphasizing the pivotal role these play in aligning with EU standards. Bosnia and Herzegovina, North Macedonia, Serbia, Montenegro, and Kosovo are analyzed in terms of their distinct obstacles, such as internal political stability, judiciary reforms, dispute resolution with neighbors, and anti-corruption efforts. For instance, North Macedonia’s settlement of a historical name dispute with Greece underscores the importance of diplomacy in the region. Serbia’s bid for membership is complicated by the necessity to normalize relations with Kosovo amidst internal and external tensions. Montenegro’s recent political transitions illustrate its dedication to democratic principles and Euro-Atlantic alliances as it pursues EU accession. Kosovo’s journey is marked by its unique international recognition issues and the implications of recent EU sanctions following ethnic conflicts. The article argues that while progress has been made, the EU accession journey for these nations will require sustained commitment, comprehensive reforms, and adept negotiation to surmount the hurdles ahead. It is through such concerted efforts that the Western Balkan countries can advance towards achieving their EU membership goals, with the collective process shaping the region’s European perspective and integration.

In this paper, we study evolution inclusions on Gelfand triple with not fixed times of impulses. We assume that the right-hand side satisfies some mild conditions to prove existence of solutions. Then we prove a continuous dependence of the solution set on the initial conditions, impulsive surfaces and the right-hand side under one-sided Lipschitz condition. Illustrative examples of partial differential inclusions are provided.

Freshwater macroinvertebrates are a diverse group and play key ecological roles, including accelerating nutrient cycling, filtering water, controlling primary producers, and providing food for predators. Their differences in tolerances and short generation times manifest in rapid community responses to change. Macroinvertebrate community composition is an indicator of water quality. In Europe, efforts to improve water quality following environmental legislation, primarily starting in the 1980s, may have driven a recovery of macroinvertebrate communities. Towards understanding temporal and spatial variation of these organisms, we compiled the TREAM dataset (Time seRies of European freshwAter Macroinvertebrates), consisting of macroinvertebrate community time series from 1,816 river and stream sites (mean length of 19.2 years and 14.9 sampling years) of 22 European countries sampled between 1968 and 2020. In total, the data include >93 million sampled individuals of 2,648 taxa from 959 genera and 212 families. These data can be used to test questions ranging from identifying drivers of the population dynamics of specific taxa to assessing the success of legislative and management restoration efforts.

The aim of this study is to examine the value relevance of accounting information, specifically the influence of accounting information on the share prices of non-financial public companies listed on the Bulgarian capital market. The data set contains twenty accounting variables and the stock prices of twenty public Bulgarian companies. The analysed period is 01.01.2015 – 31.12.2022. Descriptive statistics and Least Absolute Shrinkage and Selection Operator (LASSO) regression model are applied. The empirical analysis results show that accounting information affects share prices of the examined companies from 2015 to 2022. Addionally, LASSO regression model is an appropriate model for identifying significant accounting information variables that influence stock prices. The findings of the study offer practical implications for various stakeholders, including investors, policymakers, and financial analysts.

Water resources are vital for life, yet they are exposed to various risks. In the estern Rif of Morocco, the Oued Kert is a crucial water resource for a large population. Therefore, evaluating their health status is essential to ensure their optimal preservation. In this context, five stations (S1, S2, S3, S4, and S5) were monitored, during the four campaigns (September, December, March, and June 2022), to assess the physicochemical quality of water. In this sense, seven parameters were measured, temperature, pH, electrical conductivity (EC), Biochemical oxygen demand (BOD5), Chemical oxygen demand (COD), nitrates, and ammonium. In addition, an evaluation of metal contamination was conducted during a single campaign (May 2022) by measuring four elements (Al, Fe, Li, and Mn). The levels of electrical conductivity (greater than 3000 μS cm⁻¹), and COD (greater than 40mg L⁻¹ in S2, S3, and S4) indicate poor water quality, while, the average concentrations of ammonium classify these waters as of moderate quality. The results of metal contamination revealed the presence of iron (Fe) at a concentration of 1.9 mg L⁻¹ in S5, classifying these waters as of moderate quality according to Moroccan water quality standards.