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Biblioteka informuoja, 2025 Nr. 15 (712)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.15 (712)202
Investigation of soil reinforced with geogrid: mechanical properties and development of their evaluation model
No full textDisertacijoje nagrinėjami automobilių kelių žemės sankasos pylimų gruntai, armuoti geotinklais. Grunto ir geotinklo tarpusavio sąveiką lemia grunto ir geotinklo fizikinės bei mechaninės savybės. Siūloma gruntą ir geotinklą vertinti kartu kaip kompozitinę medžiagą – ekvivalentinį sluoksnį. Toks vertinimas leidžia supaprastinti geotinklais armuoto pylimo projektavimą baigtinių elementų ar analitiniais metodais. Disertacijos tikslas – sukurti grunto ir geotinklo vertinimo modelį, kuris leistų grunto ir geotinklo sąveiką vertinti kaip ekvivalentinį sluoksnį su alternatyvaus sluoksnio parametrais.
Disertaciją sudaro įvadas, trys skyriai, rezultatų apibendrinimas, 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.
Pirmajame skyriuje pateikiama atlikta literatūros analizė, kurioje apžvelgti automobilių kelių žemės sankasos pylimai, silpnų gruntų stiprinimo metodai, geotinklų taikymas, grunto, armuoto geotinklu, tyrimo metodai, rezultatus lemiantys veiksniai, skaitinio modeliavimo galimybės. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje pristatoma geotinklu armuoto grunto eksperimentinių tyrimų programa ir pateikiami tyrimų rezultatai, kai gruntai nearmuoti ir gruntai armuoti geotinklu.
Trečiajame skyriuje skaitiniu modeliavimu tiriami kelių sankasos pylimai. Nustatomos išvestinių parametrų reikšmės, naudojamos atliekant geotinklu armuoto grunto skaitinį modeliavimą baigtinių elementų metodu. Analitiniais metodais nustatoma optimali geotinklo pozicija pylime ir ekvivalentinio sluoksnio storis, kuriam galioja vertinimo modelio parametrai. Pa-siūlomas grunto ir geotinklo sąveikos vertinimo modelis.
Disertacijos tema paskelbti 9 straipsniai: trys – referuojamuose Web of Science duomenų bazės leidiniuose, turinčiuose citavimo rodiklį, vienas – referuojamame Web of Science duomenų bazės konferencijų leidinyje, vienas – referuojamame Scopus duomenų bazės konferencijų leidinyje, trys – recenzuojamuose tarptautinės konferencijos straipsnių rinkiniuose, vienas – konferencijų straipsnių rinkinyje. Disertacijos tema perskaityti 6 pranešimai Lietuvos ir kitų šalių konferencijose.The dissertation investigates road construction and subgrade soils reinforced with geogrids. The interaction between the soil and the geogrid is influenced by their physical and mechanical properties. The proposal is to evaluate the soil and geogrid together as a composite material. This approach simplifies the design of geogrid-reinforced structures using finite element or analytical methods. The primary purpose of this dissertation is to develop a model for evaluating the interaction between soil and geogrid, allowing this interaction to be assessed as an equivalent layer (without geogrid) with alternative layer parameters.
The dissertation comprises an introduction, three chapters, general conclusions and references.
The introduction presents the research problem, the importance of the dissertation and the study object. It describes the dissertation’s purpose and tasks, the research methodology, scientific novelty, the practical significance of the results, and defended statements. The introduction concludes by listing the author’s publications on the subject of the dissertation and presentations at conferences and defining the dissertation’s structure.
The first chapter reviews the literature on road construction, methods for strengthening weak soils, using geogrids, laboratory methods for investigating soil reinforced with geogrids, factors influencing the results, and the possibilities of numerical modelling. The chapter closes with conclusions and reconsidered tasks.
The second chapter presents the experimental research program on soil reinforced with geogrids and provides the laboratory results for unreinforced soils and soils reinforced with geogrids.
The third chapter investigates road construction using numerical modelling. It determines the values of derived parameters used in the finite element method for modelling soil reinforced with geogrids. Analytical methods are used to determine the optimal position of the geogrid in the embankment and the thickness of the equivalent layer for which the evaluation model parameters are applied. A soil-geogrid interaction evaluation model is proposed.
Nine articles were published on the subject of the dissertation: three articles in journals listed in the Web of Science database with a citation index, one article in Web of Science conference proceedings, one article in Scopus conference proceedings, three articles in peer-reviewed international conference materials, and one article in conference materials. Six presentations were given on the subject at conferences in Lithuania and abroad
Multi-criteria evaluation of sustainable supply chain management in construction companies
No full textDisertacijoje nagrinėjama statybos sektoriaus įmonių tvariosios tiekimo grandinės valdymo (TTGV) problematika. Pagrindinis tyrimo objektas – statybos įmonės, kuriose taikomas tvariosios tiekimo grandinės valdymas. Pagrindinis disertacijos tikslas – sudaryti TTGV rodiklių sistemą ir sukurti vertinimo priemonę, kuri leistų įvertinti tvariosios tiekimo grandinės valdymą statybos įmonėse, taikant daugiakriterius sprendimų priėmimo metodus.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autorės publikacijų disertacijos tema sąrašai ir trys priedai.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimo objektas, formuluojamas darbo tikslas ir uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos autorės disertacijos tema paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra.
Pirmajame skyriuje pateikta naujausių mokslinių tyrimų analitinė apžvalga, siekiant apibrėžti tvariosios tiekimo grandinės valdymą ir jo vertinimą. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje pateiktos statybos įmonių TTGV vertinimo priemonės
teorinės nuostatos: sudaroma TTGV tvarumo rodiklių sistema, pateikiami tvarumo rodiklių reikšmingumo nustatymo ir daugiakriterių sprendimų priėmimo metodai (DEMATEL, BWM ir MABAC) ir parengiama metodika tvarumo rodiklių reikšmingumui bei originaliam, darbo autorės siūlomam, kompozitiniam TTGV statybos įmonėse į(si)vertinimo indeksui nustatyti.
Trečiajame skyriuje tiriamos siūlomos vertinimo priemonės praktinio taikymo galimybės tvarumui į(si)vertinti ir sprendžiamas tiekėjų parinkimo uždavinys Lietuvos statybos įmonėje. Skyriaus pabaigoje aptartos statybos įmonių tvariosios tiekimo grandinės valdymo vertinimo priemonės praktinio taikymo įmonėse perspektyvos ir galimos tolesnių tyrimų kryptys.
Disertacijos tema paskelbti 6 moksliniai straipsniai: du – žurnaluose, įtrauktuose į Web of Science sąrašą, du – recenzuojamų konferencijų straipsnių rinkiniuose, du – recenzuojamame Lietuvos konferencijos straipsnių rinkinyje. Disertacijos tema perskaityti penki pranešimai Lietuvos ir kitų šalių konferencijose, darbo rezultatai pristatyti seminare Rygos technikos universitete.The dissertation examines the challenges of sustainable supply chain management in the construction sector. The main research object is construction companies that apply sustainable supply chain management. The primary goal of the dissertation is to create a conceptual tool that allows for evaluating Sustainable Supply Chain Management (SSCM) in construction companies using multi-criteria decision-making methods.
The dissertation consists of an introduction, three chapters, general conclusions, a list of references, a list of publications by the author on the dissertation topic, and three appendices. The introduction discusses the research problem and relevance of the work, describes the research object, formulates the goal and objectives, and presents the research methodology, scientific novelty, practical significance of the results, and the defended statements. At the end of the introduction, the author’s publications and conference presentations are listed related to the dissertation topic, as well as the structure of the dissertation.
The First Chapter is dedicated to the literature review, providing an analytical overview of the latest scientific research conducted in Lithuania and internationally. The aim is to define what sustainable supply chain management is and how it can be assessed. The chapter ends with conclusions and the thesis tasks.
The Second Chapter presents the theoretical principles of the SSCM tools for construction companies, including an overview of the formation of the SSCM sustainability indicator system and multi-criteria decision-making methods. The following methods are discussed in detail: the expert method for determining indicator significance, the multi-criteria DEMATEL, BWM, and MABAC. Finally, the methodology for constructing the composite SSCM self-assessment index for construction companies is reviewed.
The Third Chapter explores the practical application of the proposed tool for assessing sustainability in real construction companies. A methodology and an algorithm are proposed for implementing the conceptual tool to evaluate sustainable supply chain management in a real construction company.
Six scientific articles were published on the topic: two in journals indexed in the Web of Science list, two in referenced conference paper collections and two in a peer-reviewed collection of conference papers in Lithuania. Additionally, five presentations related to the dissertation topic were delivered at conferences in Lithuania and other countries, and the results were presented at a seminar at Riga Technical University
ESG integration in the Baltic investment landscape: progress, challenges, and future directions
No full textThis study investigates the integration of Environmental, Social, and Governance (ESG) factors by financial
investors in the Baltic region, focusing on developments between 2021 and 2024. Using a structured survey and
follow-up interviews, we explore investor motivations, challenges, and regulatory impacts. Findings reveal that 88% of
respondents now apply ESG criteria, driven largely by regulation, although 12% question its added value. Persistent issues
include data quality and standardization. The results inform ESG policy, implementation strategies, and comparative
analysis of regional ESG maturity.Taip / Ye
Investigation of financial fraud detection by using big data analytics
No full textThe aim of this study is to examine the application of big data analytics in financial fraud detection, considering
advancements in modern technology and the increasing complexity of financial crime schemes. The research
is based on an extensive review of the scientific literature, data synthesis, and the application of empirical methods,
including clustering analysis using the UMAP algorithm, graphical visualization techniques, and descriptive statistics,
to systematically assess fraud detection mechanisms and their effectiveness. The findings reveal that advanced artificial
intelligence techniques, such as deep neural networks and random forest models, enable the efficient detection of
financial fraud in real time. Big data analytics not only facilitates the processing of vast financial transaction datasets
but also allows for the integration of diverse data sources and the development of adaptive predictive models capable
of adjusting to evolving fraud patterns. However, the study also highlights critical challenges, including data quality
assurance, privacy protection, and the need for significant computational resources. The practical significance of this
research lies in the development of more effective financial fraud prevention strategies, enhancing the resilience and
trustworthiness of the financial sector. These insights are particularly valuable for banks, insurance companies, and
other financial institutions seeking to mitigate fraud risks and safeguard clients from potential losses. The originality of
the study is reflected in its systematic evaluation of the application of big data analytics in financial fraud prevention,
grounded in the integration of theoretical and practical knowledge.Taip / Ye
Strategic use of artificial intelligence in enterprise supply chain management
No full textThis study analyzed the strategic use of artificial intelligence (AI) in supply chain management to optimize
efficiency, accuracy, and decision-making. A comprehensive review of academic literature and relevant business case
studies was conducted to assess the impact of AI on logistics process optimization, decision-making, and operational
efficiency within the supply chain. Analytical, inductive, and deductive methods were applied to critically break down
and examine the collected information. The results revealed that the implementation of AI brings significant benefits.
For example, Lithuanian trade company Maxima has successfully reduced inventory levels by 20% and improved sales
forecast accuracy by 15% through AI-driven demand prediction systems. Similarly, another company Eugesta has experienced
a 30% reduction in inventory levels and a 20% improvement in sales forecast accuracy due to AI algorithms.
Building on this research, the authors propose a model that integrates AI-driven supply chain optimization strategies,
outlining key factors for enhancing business efficiency, predictive accuracy, and decision-making. The proposed model
aims to serve as a structured framework for companies looking to leverage AI for sustainable competitive advantage in
supply chain management.Taip / Ye
Enhancing green sustainable growth through green innovation: the moderating role of perceived marketplace influence
No full textIn the context of technologies driving corporations’ investment in green innovation initiatives, this study
employs a mixed-methods approach, integrating qualitative thematic analysis and quantitative structural equation
modeling to examine how green innovation activities influence consumer attitudes, purchase intentions, and brand
defense behaviors. Qualitative insights drawn from consumer narratives enrich the quantitative findings by uncovering
deeper motivations and emotional factors influencing consumer behavior towards green products. The findings reveal
that firms’ green innovation significantly positive impact on customer green behaviors through their environmental
concerns and perceptions of innovation. Additionally, the customer’s perceived marketplace influence plays a crucial
role in reinforcing the customer’s perceptions of innovation on their green purchase intention, while diminishing
the customer’s environmental concerns on their green brand defense. Through green marketing strategies, including
transparent communication, credible certifications, and explicit sustainability claims, the organization’s green innovation
practices significantly influence consumer attitudes and willingness to purchase green products. Furthermore, the
findings emphasize the critical roles of brand reputation, transparency, and consumer trust in stimulating proactive
brand defense against negative publicity as well as the importance of emotional attachments and personal experiences
in driving these defensive behaviors.Taip / Ye
The liability of a notary as an economic entity providing legal services, ensuring the interests of consumers
No full textThe article examines the problematic aspects of civil liability of notaries of the Republic of Lithuania when
performing notarial actions, ensuring the interests of consumers. The principle of personal liability of a notary is revealed,
paying attention to the duality of the notary’s functions. The notary’s activities are analyzed, (not) related to
the exercise of public authority powers, reviewing the limits of civil liability of a notary as an economic entity, and the
influence of the actions of the injured person himself, raising the issue of liability. In the article, the author raises a rhetorical
question regarding the application of indirect liability of the state for damage caused by the notary’s unlawful actions,
performing functions assigned to the state, focused on the balance of interests of the notary and the state, revealing
the importance of the principle of notary independence. The author attempts to reveal the gap in legal regulation in
the context of notary civil liability, protecting the interests of both consumers and the notary from unjustified liability.Taip / Ye
Fire Classification and Detection Using a CNN-YOLO Hybrid Model for Early Warning Systems
No full textFire detection is essential for preventing and mitigating disaster impacts, requiring rapid and accurate identification to minimize damage and loss of life. Conventional fire detection systems based on sensors often lead to false alarms and struggle with delayed responses. This study proposes a hybrid CNN-YOLO approach, where a CNN is first used to classify images as fire or non-fire, followed by YOLOv8, which detects and localizes fire regions. The CNN model was trained on images collected from open databases, such as Kaggle, ensuring a diverse range of fire scenarios for classification. The CNN model achieved training, validation, and testing accuracies of 99.98%, 94.12%, and 93.01%, respectively, demonstrating its reliability in distinguishing fire from non-fire images. Additionally, the YOLOv8 model showed progressive accuracy improvements throughout 107 epochs, achieving mAP50 and mAP50-95 scores of 0.765 and 0.486, respectively. The hybrid model achieved an overall accuracy of 90%, with precision of 0.96, recall of 0.93, and an F1-score of 0.95, highlighting its practical effectiveness in detecting fire across diverse environmental contexts. This proposed hybrid approach demonstrates its potential for enhancing early fire detection systems, contributing to disaster management and mitigation efforts. Future research will focus on addressing misclassification issues, refining the model architecture, and expanding the dataset to improve robustness and generalization.Taip / Ye