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Investigation of microrobot movement trajectory planning using sensor data fusion
No full textDisertacijoje nagrinėjama mikrorobotų judėjimo trajektorijos planavimo problema. Tyrimo objektas – mikrorobotas, jo trajektoriją veikiantys robotinės sistemos elementai ir mašininio mokymosi sprendimai. Detali robotinės sistemos sudedamųjų dalių konstrukcinė analizė ir jų darbinių savybių vertinimas leidžia parinkti efektyvius sprendimus, planuojant mikroroboto judėjimo trajektoriją. Mašininio mokymosi YOLOv7 modelio naudojimas leidžia mikrorobotui efektyviai reaguoti į kintančias aplinkos sąlygas ir gebėti nustatyti tiriamojo objekto vietą. Disertacijos tikslas – nustatyti konstrukcinius elementus, labiausiai veikiančius trajektorijos planavimo efektyvumą, bei sukurti metodiką ir algoritmus, naudojant jutiklių duomenų suliejimo informaciją. Gautų eksperimentinių rezultatų analizė numato trajektorijos planavimo gerinimo rekomendacijas.
Disertaciją 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 ir uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra.
Pirmasis skyrius skirtas mokslinės literatūros apžvalgai. Jame pateikta mikrorobotų tipų ir jų valdymo sistemų apžvalga, aprašoma robotinių sistemų konstrukcinių elementų panaudojimo analizė ir mikrorobotų manipuliavimo padėties tikslumo nustatymo mechanizmas. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje pateikta mikroroboto judėjimo trajektorijos įvertinimo teorinio tyrimo metodika, mikropozicionavimo sistemos modeliavimo analizė ir visos sistemos tikslumo matavimo rezultatai, lemiantys mikroroboto judėjimo trajektorijos planavimo tikslumą.
Trečiajame skyriuje aprašomi jutiklių duomenų suliejimo mikrorobotikoje eksperimentiniai tyrimai. Pateikiami mikroroboto judėjimo trajektorijos planavimo duomenys, naudojant jutiklių duomenų suliejimo informaciją ir taikant mašininio mokymosi metodiką. Gauti roboto judesio tikslumo tyrimų duomenys leidžia įvertinti jutiklių duomenų suliejimo efektyvumą, esant skirtingoms roboto judesio trajektorijoms.
Disertacijos tema paskelbti 6 straipsniai: trys – žurnaluose, įtrauktuose į Web of Science duomenų bazę, du – periodiniuose ir vienkartiniuose leidiniuose, vienas – konferencijų medžiagoje, referuotoje Web of Science duomenų bazėje. Disertacijos tema perskaityti 6 pranešimai Lietuvos ir kitų šalių konferencijose.This dissertation deals with the problem of trajectory planning for micro-robots. The object of research is a microrobot, the elements of the robotic system that affect its trajectory, and machine learning solutions. The detailed structural analysis of the robotic system components and the evaluation of their performance allows the selection of effective solutions for the trajectory planning of the microrobot. The use of the YOLOv7 machine-learning model enables the microrobot to respond efficiently to changing environmental conditions and to locate the object of interest. This dissertation aims to identify the design elements that have a greater impact on the efficiency of trajectory planning and to develop techniques and algorithms using sensor data fusion information. The analysis of the experimental results will provide recommendations for improving trajectory planning.
The dissertation consists of an introduction, three chapters, a summary of the results, and a list of the literature used and the author’s publications on the topic of the dissertation.
The introductory chapter discusses the research problem and the relevance of the dissertation, describes the research object, formulates the aim and objectives of the work, describes the research methodology, the scientific novelty of the dissertation, the practical significance of the dissertation results, and the defended statements.
The introduction concludes with an overview of the author’s publications and conference presentations on the dissertation topic and the structure of the dissertation.
The First Chapter focuses on literature analysis. It provides the applications of microrobots, presents an analysis of actuators used in robotic systems found in the scientific literature, microrobot tools, and an overview of positioning accuracy in manipulation systems. The chapter ends with conclusions and a refinement of the dissertation objectives. The Second Chapter presents the methodology, analysis, and results of the trajectory accuracy assessment. It describes the modelling of the micro-positioning system, the theoretical research methodology and the results. The Third Chapter presents the experimental studies carried out using sensor data fusion. It describes the results obtained, which allow for assessing the accuracy of the planned trajectory of the microrobot.
Six scientific articles have been published on the subject of the dissertation: three in journals included in the Web of Science database, two in Periodicals and Occasional Papers, and one in conference proceedings referenced in the Web of Science database. The results of the research carried out in this dissertation were published in seven international scientific conferences in Lithuania and abroad
Developing and investigating a plant-based loose-fill thermal insulation material
No full textDisertacijoje nagrinėjamos birios termoizoliacinės medžiagos iš medienos perdirbimo atliekų. Darbo tikslas – sukurti atsparią ugnies ir vandens poveikiui ekologišką ir energetiškai efektyvią birią termoizoliacinę medžiagą iš medienos atliekų. Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, literatūros ir šaltinių, autoriaus mokslinių publikacijų disertacijos tema sąrašas bei santrauka anglų kalba.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose, disertacijos struktūra. Pirmame skyriuje analizuojami literatūros šaltiniai apie termoizoliacinių kompozitų įvairovę, jų klasifikavimą, struktūros tipus, naudojamas žaliavas ir priedus, naudojimo statybose būdus ir galimybes, aptariamos jų eksploatacinės savybės. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrame skyriuje pateiktos birių termoizoliacinių medžiagų gamybai naudojamų augalinės kilmės žaliavų, t. y. nevalytos pušies pjuvenos (nPP), valytos pušies pjuvenos (PP), medžio žievė (MŽ), lietuviški kanapių spaliai (LT-KS), prancūziški kanapių spaliai (PR-KS) ir dangoms naudojamų komponentų – skysto stiklo, tungų aliejaus ir plėtriojo grafito – savybės, taikomi tyrimo metodai, parinkti siekiant ištirti augalinės kilmės žaliavų ir daugiakomponenčių dangų struktūrą bei fizikines savybes.
Trečiame skyriuje pateikiami augalinės kilmės žaliavų tyrimai ir jų parinkimas biriai termoizoliacinei medžiagai formuoti. Analizuojamas daugiakomponentės suspensijos poveikis birios termoizoliacinės medžiagos šilumos laidumo koeficientui, vandens sugerčiai, paviršiaus vilgumui, pralaidumui vandens garams, terminiam stabilumui ir degumo savybėms. Taip pat pateikiami birių termoizoliacinių medžiagų iš pušies pjuvenų, padengtų daugiakomponenčių suspensijų dangomis, struktūros tyrimų rezultatai.
Disertacijos tema paskelbti 3 moksliniai straipsniai: Web of Science duomenų bazės Science Citation Index Expanded referuojamuose leidiniuose, turinčiuose cituojamumo rodiklį.The dissertation examines loose-fill thermal insulation materials from wood processing waste. The dissertation aims to create a fire- and water-resistant, environmentally friendly and energy-efficient loose-fill thermal insulation material from wood waste. The dissertation consists of an introduction, three chapters, general conclusions, lists of literature and sources, the author’s scientific publications on the topic of the dissertation, and a summary in English.
The introduction chapter discusses the research problem and the relevance of the work, describes the research object, formulates the aim and objectives of the work, describes the research methodology, scientific novelty of the work, practical significance of the work results, and defendable statements. The introduction closes by presenting the author’s publications, participation at conferences on the topic of the dissertation, and the structure of the dissertation.
The First Chapter analyses literature sources on the variety of thermal insulating composites, their classification, types of structure, raw materials and additives used, methods and possibilities of use in construction, and discusses their operational properties. At the end of the chapter, conclusions are formulated, and the dissertation tasks are specified.
The Second Chapter presents the properties of plant-based raw materials: nWC – uncleaned pine sawdust, WC – cleaned pine sawdust, MB – wood bark, LT-HS – Lithuanian hemp shives, FR-HS – French hemp shives, components used for coatings – liquid glass, tung oil, and expandable graphite, used for the production of loose-fill thermal insulating materials, and the research methods selected to study the structure and physical properties of pine wood chips with multi-component coatings.
The Third Chapter presents the research on plant-based raw materials and their selection for forming loose-fill thermal insulating materials. It focuses on the effect of a multi-component suspension on the thermal conductivity coefficient, water absorption, surface humidity, water vapour permeability, thermal stability, and flammability properties of loose-fill thermal insulating materials. It presents the results of structural studies of loose-fill thermal insulating materials from pine sawdust covered with multi-component suspension coatings.
The topic of the dissertation has been published in three scientific articles: in the Web of Science database Science Citation Index Expanded peer-reviewed publications with a citation index
Disruptive events as catalysts or disruptors to developing sustainable and resilient business models
No full textToday’s business environment is characterized by volatility and uncertainty, such as economic crises, technological
evolutions, pandemics, wars, corporate scandals, etc. These disruptive events challenge conventional business
paradigms, presenting both unabating threats and opportunities for business model obsolescence or transformation.
Our study explores the paradoxical role of disruptive events as disruptors and catalysts for creating sustainable and
resilient business models through a narrative scientific literature overview. The study analyses some critically relevant
academic literature to identify the critical mechanisms through which businesses transform and adapt their functional
frameworks during a crisis. The insightful findings indicate that disruption catalyses business model transformation
via forced experimentation, market shifts, behaviours, and reactions to regulatory changes. Conversely, disruptions
displace business models through disruptive technology, economic dilemmas, shifting marketing trends, regulatory
changes, health crises, and environmental and social dynamics. The overview characterizes strategic agility in leadership
and operations, resource-based view, business continuity planning, and circular economy principles supported by
dynamic capabilities for resilience, sustainability for competitive advantage, customer-centric approach, collaborations,
networks, and partnerships, as well as monitoring and managing risk as pillars of a sustainable and resilient business
model framework.Taip / Ye
Implementing human-robot collaboration in the production environment of the manufacturing industry in Latvia
No full textThe concept of human-centred automation has the potential for direct physical and cognitive collaboration
between humans and robots in a shared workspace. This approach changes the dynamics of existing conventional
automation in the working world. The fact that the market and research are pushing consistently in the direction of
Human-Robot Collaboration (HRC) is also highlighted by the numbers, which show how the collaborative robot market
will reach $ 12.71 billion by 2030. Research goal: To research the possibilities of implementing Human-Robot Collaboration
in the production environment of the manufacturing industry in Latvia. Research methods: secondary data
analysis and survey. Data processing methods: ranking and frequency analysis. Main findings: The frequency analysis
revealed key HRC applications such as assembly, material handling, and quality control in the Latvian manufacturing
industry. The most significant challenges were training and investment costs, while the most impactful solutions were
outsourcing expertise and providing employee training. Cross-tabulation results confirmed a substantial relationship
between HRC implementation and age, gender, and working experience.Taip / YesSocial Entrepreneurship Ecosystem Development / CSR and Environment, Social Responsibility and Governance (ESG) practices in creating value for stakeholder
Biblioteka informuoja, 2025 Nr. 14 (711)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.14 (711)202
Application of GIS technology to analyze agricultural land use trends
No full textKintantys žmonių poreikiai lemia besikeičiantį kraštovaizdį ir žemės naudojimą. Pastaraisiais metais vyksta
aktyvus miestų plėtimasis, rengiami infrastruktūros plėtros projektai bei vyksta gyvenamųjų teritorijų plėtra, šie procesai
turi tiesioginę įtaką žemės ūkio paskirties žemėms – dalis jų yra išbraukiama iš aktyvios žemdirbystės veiklos
ir pritaikoma kitoms reikmėms. Žemės naudojimo kaita atsispindi kasmetiniuose žemės ūkio naudmenų ir pasėlių
deklaravimo statistikos duomenyse, kuriuose stebimas mažėjantis paraiškų ir deklaruojamų plotų skaičius. Naudojant
GIS įrankius, bus siekiama vizualizuoti bei analizuoti erdvinius duomenis, vertinant žemės pokyčių tendencijas per
pastaruosius metus.Changing human needs determine the changing
landscape and land use. In recent years, urban development,
infrastructure development projects and the development of
residential areas have been observed, these processes have a
direct impact on agricultural lands – some of them are removed
from active agricultural activities and adapted for other
needs. The change in land use is reflected in the annual declaration
of agricultural land and crops, and the number of applications
and areas is decreasing. Using GIS, the aim will be to
visualize data and analyse spatial trends, assess land change
trends over the years.Taip / Ye
Biblioteka informuoja, 2025 Nr. 42 (739)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.42 (739)202
The export of social and democratic habitus as a tacit guarantee in the pursuit of open strategic autonomy in the European Union: the case of the Global Gateway in Africa
No full textIn an increasingly fragmented and multipolar international system, the European Union (EU) seeks to maintain
its geopolitical relevance by advancing inclusive cooperation models that reinforce its foundational political and
social values. These values – anchored in the European Social Pillar (ESP), regulatory frameworks, and democratic
governance – serve as both an internal safeguard and an external strategy for reinforcing the EU’s role as a normative
power. However, contemporary global challenges, including geopolitical rivalries, energy dependencies, and technological
disruptions, necessitate a more structured approach to securing strategic autonomy while maintaining multilateral
engagement. This paper explores the concept of open strategic autonomy as a guiding principle of EU foreign policy,
analyzing how initiatives such as the Global Gateway Strategy function as geopolitical instruments for regulatory influence
and economic engagement. A key focus is on the EU’s engagement with Africa, where the Global Gateway serves
as a counterbalance to alternative cooperation models, such as China’s Belt and Road Initiative (BRI). The paper proposes
a conceptual model for understanding the interplay between internal governance, strategic autonomy, and global
influence. This model offers a structured approach to aligning EU regulatory power, economic partnerships, and geopolitical
stability in a way that ensures both internal resilience and external projection of European values.Taip / YesHORIZON-MSCA- 2022-SE-01Cluster for innovative energy101129820
Holistic View on Decision-making in Cyber Defense Exercises: A Case Study Based in Amber Mist
No full textDecision-making in cyber defense exercises (CDX) is a complex process that extends beyond technical proficiency, incorporating cognitive, strategic, and behavioral elements. This study presents a holistic view approach to decision-making in CDX, emphasizing technical expertise, situational awareness, teamwork, and emotional resilience using the Amber Mist cyber defense exercises as a case study. A multidimensional assessment framework was proposed and analyzed. It evaluates the decision-making aspects of the CDX participants. Findings highlight the importance of incorporating behavioral and collaborative dimensions alongside traditional decision-making frameworks. By analyzing data from Amber Mist 2024 cyber defense exercises, key factors were identified that influence decision quality. Findings suggest that a holistic assessment of decision-making, integrating both human factors and technical aspects, provides a more accurate measure of the cybersecurity competence of the participants. This research contributes to the improvement of training methodologies and the enhancement of cybersecurity training programs.Taip / Ye
Dempster-Shafer WASPAS Decision-Making Method for the Selection Wall Construction of a Single-Family House
No full textThe application of multi-criteria decision-making methods is particularly useful in constructing single-family houses when it is necessary to select the optimal types of wall construction. This paper presents a new WASPAS DS method based on the Dempster-Shafer theory. The weights of the chosen criteria (cost, strength, durability, ecological impact, microclimatic suitability and construction duration) are estimated using the SWARA method. They help to make informed decisions that balance sustainability goals, cost-effectiveness and functionality. A numerical example shows how walls' cost, strength and ecological impact influence the choice of wall construction for a single-family house. The applicability of the newly proposed WASPAS DS method in solving MCDM problems related to unclear criteria and expert weights allows for flexible adaptation of criterion weights to specific project requirements. This ensures a more efficient decision-making process and long-term sustainability of construction projects.Taip / Ye