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Generative tools of AI in education
No full textSince generative tools of Artificial Intelligence appeared in education, ongoing discussion arose. Still, higher education institutions argue if generative tools can be used, and if yes, what exactly can be accepted. The purpose of this study is to investigate for what exactly students use the generative tool Chat GPT in their studies, as well as to determine if there is a statistically significant difference between students representing different fields of study in terms of usage of Chat GPT in general, as well as in evaluation of the knowledge. The objectives of the study are to research recent scientific findings, as well as to analyze the results of the survey created by authors, which was distributed in Latvia, Lithuania, Ukraine, Bulgaria and Uzbekistan. Methods of the study are analysis of the recent findings and statistical analysis of the survey. To test hypotheses, the authors employed the Kruscal-Wallis non-parametric test for both hypotheses, where authors tested if there are statistically significant differences between answers of students from different education fields. The final results highlight the use of Chat GPT by students in higher education.Taip / Yes
Gender inequity in an European Union flooded with immigrants
No full textGender inequality is a phenomenon that everyone denies on a declarative level, but which we all know exists. When we talk about gender discrimination, the females are the most affected, although in the European Union there are laws that offer equal opportunities to women and men. In an ever-changing landscape for Europe, it should not be forgotten that immigrants are subject to the same trends as the local population, but non-European women can negatively impact the statistics on efforts to mitigate this discrimination. This paper aims to analyse the phenomenon of gender inequality in the labour market. We consider analysing indicators such as: employment rate, salary level, type of employment (part-time / full-time), retention at work, number of worked hours, as well as ease of finding a job. This analyse is focused on the European Union, for the years 2015–2022. We are expecting a decreasing trend, but combined with the necessity to re-skill human resources for the jobs of the future.Taip / Yes
Discrete cracks approach for deformational analysis of reinforced concrete beams
No full textThe discrete cracks approach is proposed for deformational analysis of reinforced concrete members as an alternative method of the classical smeared crack techniques. It evaluates analytically the effects of concrete shrinkage, developed in a period before loading, and bond at the contact interface of reinforcing bars and surrounding concrete. Consequently, the history of evolution of the major, discrete cracks patterns is considered at a monotonically increased loading. The cracking process is analyzed by superposing the symmetrical and asymmetrical bond problems during it. The asymmetrical problem is resolved by introducing the increments of forces and bending moments due to appearance of major cracks. The proposed approach is applied for prediction of the stress-strain state and deflections of the beams with different ratios of reinforcement. The mid-span deflections, calculated using the discrete cracks model, agree sufficiently well with those obtained by the Eurocode-2 technique based on the smeared crack approach. The tension stiffening effect is clearly indicated for the beam with a small reinforcement ratio
From barriers to bridges: enhancing labour market dynamics through refugee integration in Europe
No full textThis article examines the critical role of refugee integration into labour markets as a solution to workforce shortages faced by companies across Europe. With a growing gap between labour demand and the available workforce, the integration of refugees not only addresses economic needs but also supports social inclusion and diversity. Through a comprehensive literature review, this study highlights the mutual benefits for both refugees and companies, including enhanced cultural diversity, innovation, and economic growth. Furthermore, it presents empirical findings from recent research conducted in several European countries targeting refugees, business support organisations as well as NGOs. The result of this survey offers insights into the successes and hindrances of integration practices. Key challenges such as language barriers, credential recognition, and cultural differences are discussed. By providing a nuanced understanding of the complexities and benefits involved, this study contributes to the ongoing discourse on labour market dynamics and the potential of refugees to enrich host countries’ economies and societies.
Biblioteka informuoja, 2024 Nr. 9 (653)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.9 (653)202
Selection of an optimum axially compressed closed cross-section thin-walled built-up column /
No full textThis article focuses on the analysis of axially compressed thin-walled built-up closed cross-section columns. The built-up nature of the cross-section is carefully considered in the calculation procedures and optimization constraints, accounting for the connection of profiles through the flanges within the cross-section. The calculation procedures are based on Eurocode 3 [1], which encompasses local, distortional, and global buckling forms. Five types of closed column cross-sections, ranging in height from 2 to 4 m, and subjected to axial loads of 50, 100, 200, and 500 kN, were thoroughly analyzed and optimized. The first type of cross-section examined was a square cross-section without stiffeners, while the remaining types featured four web stiffeners with varying geometrical constraints. The constrained nonlinear optimization solver, fmincon in Matlab software, was selected for the optimization problem. The obtained optimal cross-section results indicate that the square cross-section consistently exhibited the lowest effectiveness across all column heights and axial load combinations. In contrast, the most effective cross-section type transformed to a form, similar to a circle. Moreover, cross-section types with deeper stiffeners were associated with thinner profile thickness. A comprehensive summary of the results demonstrates that the effective area ratio within the cross-section was higher for smaller column heights and larger axial loads across all cross-section types. In conclusion, this study provides valuable insights into the analysis and optimization of axially compressed thin-walled built-up closed cross-section columns. The findings underscore the superiority of cross-sections that adopt a circular form and feature deeper stiffeners, resulting in enhanced structural effectiveness
Peculiarities of service delivery in the context of changes caused by the external environment
No full textThis research analyzes the integration of change management within service delivery, focusing on the service sector’s adaptability to external environmental changes. Employing a comparative and critical analysis of scientific literature and the synthesis of obtained results, the research aims to identify service characteristics’ chronological evolution, examine service delivery peculiarities, and develop a change management-based service delivery system. Findings indicate the service sector’s resilience and the necessity for organizations to proactively recognize change in external environment, emphasizing the importance of early detection and adaptation to environmental shifts for uninterrupted service delivery.Taip / Yes
Development of autoclave fibre cement composite and investigation of its properties under standard fire conditions
No full textDisertacijoje tiriamos atliekos, susidarančios gaminant putstiklio granules, ir anglies pluošto panaudojimo galimybės, kuriant autoklavinio fibrocemento kompozitą. Disertacijos tikslas – padidinti autoklavino fibrocemento kompozito mechaninį atsparumą naudojant atliekas, susidarančias gaminant putstiklio granules, ar anglies plaušo priedus, ir įvertinti standartinio gaisro temperatūros (iki 841 °C) poveikį jo mechaninėms savybėms.
Disertaciją sudaro įvadas, trys skyriai, rezultatų apibendrinimas, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, tyrimų objektas, formuluojamas darbo tikslas ir uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pateikti disertacijos tema autoriaus pranešimai konferencijose,paskelbtos publikacijos ir disertacijos struktūra.
Pirmasis skyrius skirtas mokslinės literatūros apžvalgai ir analizei. Jame nagrinėjamas autoklavinio fibrocemento hidratacijos procesas. Apžvelgiamas aukštos temperatūros poveikis cementinėms medžiagoms ir priedų panaudojimas siekiant padidinti jų atsparumą aukštai temperatūrai. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje yra aprašytos darbe naudojamos žaliavos, jų charakteristikos ir savybės. Taip pat pateikta autoklavinio fibrocemento kompozito mišinių sudėtis, tyrimo metodai ir naudota įranga.
Trečiajame skyriuje pateikiami autoklavinio fibrocemento su atliekos, susidarančios gaminant putstiklio granules, ir atskirai su anglies pluošto priedais poveikio mikro- ir makrostruktūroms, fizikinėms ir mechaninėms savybėms rezultatai. Nagrinėjama, kaip pasikeičia kompozito su panaudotais priedais mikro- ir makrostruktūros, fizikinės ir mechaninės savybės po standartinio gaisro temperatūros poveikio. Nustatyta modifikuotojo kompozito degumo klasė ir atsparumas ugniai. Pateikiamos trečiojo skyriaus išvados, o po skyriaus – bendrosios disertacijos išvados.
Disertacijoje aprašyti tyrimų rezultatai paskelbti trijuose moksliniuose straipsniuose žurnaluose įtrauktuose į Clarivate Analytics Web of Science duomenų bazę ir pristatyti trijose nacionalinėse ir tarptautinėse mokslinėse konferencijose.The dissertation examines the possibilities of using the waste generated during the production of blowing agent granules and carbon fibres in the development of autoclaved fibre cement composite. The dissertation aims to increase the mechanical resistance of the autoclaved fibre cement composite using the expanded glass granules producing waste or carbon fibre additives and to evaluate the effects of standard fire temperature (up to 841 °C) on its mechanical properties.
The dissertation comprises an introduction, three chapters, a result conclusion, references and a list of the author’s publications on the dissertation topic.
The introduction chapter discusses the researched problem, relevance of this work, research object, work goal and formulated exercises, the research methodology, scientific recency, practical meaning of work results, and the defended statement. The introduction closes with a list of the author’s presentations at conferences on the dissertation topic, a list of published publications, and the dissertation structure.
The first chapter is dedicated to the overview and analysis of scientific literature. It reviews the effects of high temperatures on cementitious materials and the use of additives to increase their resistance to high temperatures. At the end of the chapter, conclusions are formulated, and the tasks of the dissertation are clarified.
The second chapter describes the raw materials used in the work, their characteristics and their properties. It also provides information on the composition of autoclaved fibre cement composite mixture, research methods, and equipment used.
The third chapter presents the results of the micro- and macro-structure, physical and mechanical properties of autoclaved fibre cement with waste generated during the production of blowing agent granules and separately with carbon fibre additives. It analyses how the micro- and macro-structure, as well as the physical and mechanical properties of the composite with the used additives, change after exposure to the standard fire temperature. The reaction to fire class and fire resistance of the modified composite has been determined. The chapter closes with conclusions. Finally, general conclusions are presented.
The research results described in the dissertation were published in three scientific publications in journals that are included in the Clarivate Analytics Web of Science database and presented at three national and international scientific conferences.Taip / Ye
Effect of laser boronising on the structure and properties of the maraging steel surface layer
No full textDisertacijoje nagrinėjamas 18 % Ni martensitinis sendinamas plienas 1.2709 (DIN), kuris plačiai naudojamas gaminant įvairių technikos sričių gaminius ir detales adityviosios gamybos metodais, pvz., selektyviuoju lazeriniu lydymu (SLL). Šio plieno paviršiaus kietumui padidinti ir atsparumui dilimui pagerinti darbe pasiūlytas lazerinio įborinimo metodas, kuris galėtų tapti efektyvia, mažiau energijos sąnaudų reikalaujančia, laiką taupančia ir saugesne aplinkai alternatyva šiuo metu taikomam termocheminio įazotinimo metodui.
Darbą sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašomi tyrimų metodai, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, pristatomi ginamieji teiginiai.
Pirmajame skyriuje pateikta literatūros apžvalga ir analizė adityviosios gamybos, martensitinių sendinamų plienų ir metalinių paviršių modifikavimo metodų temomis. Skyriaus pabaigoje pateiktos išvados ir patikslinti diseratacijos uždaviniai.
Antrajame skyriuje aprašytos tyrimams naudotos medžiagos, lazerinio įborinimo metodika, įborintų paviršių charakterizavimo metodai bei naudota įranga.
Trečiajame skyriuje pateikti tyrimų rezultatai ir jų analizė. Nagrinėjamas lazerinio įborinimo procesas, taikant jį iki ir po plieninių bandinių terminio apdorojimo, jo poveikis modifikuotų paviršių sandarai, savybėms bei pagrindinio metalo savybėms terminio poveikio zonoje.
Disertacijos tema paskelbti 5 straipsniai, du iš jų įtrauki į Clarivate Analytics Web of Science duomenų bazę, o tyrimų rezultatai pristatyti 10 nacionalinių ir tarptautinių mokslinių konferencijų.The dissertation examines 18% Ni maraging steel 1.2709 (DIN) widely used in producing products and parts across various technical fields by additive manufacturing methods, e.g., selective laser melting (SLM). To enhance the surface hardness and improve the wear resistance of this steel, a laser alloy-ing method was proposed, which could become an effective, less energy-consuming, time-saving and environmentally safer alternative to the currently applied thermochemical nitriding method.
The work consists of an introduction, three chapters, general conclusions, lists of used literature and the author’s publications on the dissertation topic.
The introductory chapter discusses the research problem, the relevance of the work, describes the object of the research, formulates the purpose and tasks of the work, describes the research methods, the scientific novelty of the work, the practical significance of the work results, and presents the defended statements.
The first chapter presents a literature review and analysis on the topics of additive manufacturing, maraging steels and metal surface modification methods. The chapter closes with conclusions and specifies dissertation tasks.
The second chapter describes the materials used for the research, the laser boronising methodology, the boronised surface characterisation methods and the equipment used.
The third chapter presents the research results and their analysis. The process of laser boronising is examined, applying it before and after heat treatment of steel samples, its effect on the structure and properties of modified surfaces and the properties of the base metal in the heat-affected zone.
Five articles were published on the dissertation topic, two of them were published in publications of the Clarivate Analytics Web of Science database and research results were presented at 10 national and international scientific conferences.Taip / Ye
