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Tarptautinė mokslinė konferencija NETOBULAS MODERNIZMAS (2024)
No full textDOCOMOMO International„Domus galerija“The Lithuanian National Commission for UNESCO / Lietuvos nacionalinė UNESCO komisijaDepartment of Cultural Heritage under the Ministry of Culture of the Republic of Lithuania / Kultūros paveldo departamentas prie LR Kultūros ministerijo
Analysis of bicycle and pedestrian traffic conflict points
No full textStraipsnyje nagrinėjami dviračių ir pėsčiųjų eismo konfliktiniai taškai Vilniaus mieste, kurie yra vertinami eismo saugumo požiūriu, atliekami pažeidžiamų eismo dalyvių srautų ir elgsenos tyrimai. Aptariamos dažniausios konfliktinių situacijų priežastys, tokios kaip netinkama infrastruktūra, pavojų eismo dalyviams keliantys veiksmai. Konfliktinės situacijos vertintos remiantis olandų eismo konfliktų stebėjimo metodu. Nustatytos pagrindinės problemos, kurios lemia konfliktinių situacijų gausą bei sunkumą, identifikuotas inžinerinių eismo saugumo priemonių taikymo dviračių ir pėsčiųjų eismo konfliktiniuose taškuose poreikis.The article examines the conflict points of bicycle and pedestrian traffic in the city of Vilnius These conflict points are evaluated from the point of view of traffic safety, the flows of traffic participants and their behavior are analyzed. The most common causes of conflict situations are discussed, such as inadequate infrastructure and dangerous actions of road users. Conflict situations are analyzed based on the Dutch traffic conflict monitoring method (DOCTOR). The main problems that determine the severity of conflict situations and the need for the application of engineering traffic safety measures at bicycle and pedestrian traffic conflict points have been identified.Taip / Ye
Analysis of soil-geogrid interaction and alternative soil layer approach for improved road embankment stability
No full textRoad embankments are critical elements of modern transportation infrastructure that provide support and stability to the roadway. However, embankments can be vulnerable to slope instability due to factors such as poor soil quality, excessive loads, frost, and steep slopes. To address these challenges, engineers have developed various methods to reinforce embankments, including the use of geogrids. In this study examined mechanical properties of soil-geogrid interaction using laboratory testing method such as triaxial compression. Also, geotechnical software, such as GEO5, to assess the stability and safety of the structures was used. Analysis revealed that the required thickness of an additional soil layer to achieve the same slope stability as that with geogrid reinforcement depends on the soil type and slope steepness. Specifically, the higher the apparent cohesion of the soil, the smaller the thickness of the additional layer, while steeper slopes require greater thickness of the additional layer of soil. We also found that an alternative soil layer with apparent cohesion as a composite material has potential in slope stability calculations, but requires further analysis
The assessment of youth financial literacy impact on saving
No full textFinancial literacy and savings are very important for efficient personal finance management. If the person has an excellent financial literacy level, the amount of savings is very high. This article aims to assess the link between youth financial literacy and savings. The following tasks have been implemented: to analyse the scientific literature about financial literacy and personal finance management and assess youth financial literacy’s impact on savings. In the article, the following methods of analysis are used: an analysis and summary of the scientific literature, an analysis of the survey data, and correlation regression analysis.Taip / Yes
Vilniaus Gedimino technikos universitetas 2023 metai
No full textVilniaus Gedimino technikos universiteto mokslinis informacinis leidinys57202
The market dance between the rhythm of bitcoin prices and the S&P 500 Index
No full textThe financial markets experienced a thrilling saga between 2020 and 2023, characterised by a series of unprecedented events and captivating dynamics that set the stage for a compelling exploration of the interaction between bitcoin prices and the S&P 500 Index. This study systematically examines the correlation between bitcoin prices and the S&P 500 Index using the Yahoo Finance dataset over a 48-month period. Using the extensive Yahoo Finance dataset and the analytical capabilities of R Statistics & R Studio, the present research covers a comprehensive period of 48 months (2020-2023). The study identifies a robust positive correlation, quantified by a correlation coefficient of 0.7726, indicating a significant alignment between bitcoin price movements and the S&P 500 index. Monthly price variables obtained from an open-source repository provide a comprehensive overview of the relative dynamics of these financial assets. This analysis provides valuable insights into the current behaviour of bitcoin and the S&P 500 index, as well as concise observations on the dynamics of their correlation.Taip / YesIScientific Grant Agency of the Ministry of Education and Science of the Slovak Republic and the Slovak Academy of Sciences (VEGA)1/0110/2
Azerbaidžano ir Lietuvos gyvenamųjų pastatų energinio efektyvumo palyginimas
No full textThis study compares energy efficiency in residential buildings in Azerbaijan and Lithuania, regions with contrasting climates, to highlight how local conditions influence energy demands. Employing simulation data, we found significant differences: Azerbaijan’s buildings require more energy for cooling, while Lithuania’s need more for heating. The analysis indicates a 26.5% greater cooling demand in Azerbaijan and a 13.8% higher heating demand in Lithuania, underscoring the necessity of region-specific energy efficiency strategies. Additionally, the study explores the reduced energy consumption by fans and pumps, suggesting the potential for passive ventilation or the strategic deactivation of systems to conserve energy. These findings offer crucial insights for developing tailored, sustainable infrastructure in diverse climatic conditions.Šiame tyrime lyginamas energijos vartojimo efektyvumas gyvenamuosiuose pastatuose Azerbaidžane ir Lietuvoje – skirtingo klimato regionuose – siekiant išsiaiškinti, kokią įtaką energijos poreikiams turi vietos sąlygos. Remdamiesi modeliavimo duomenimis, nustatėme reikšmingų skirtumų: Azerbaidžano pastatams reikia daugiau energijos vėsinimui, o Lietuvos – šildymui. Atlikus analizę paaiškėjo, kad Azerbaidžane reikia 26,5 % daugiau vėsinimo, o Lietuvoje – 13,8 % daugiau šildymo energijos, todėl būtina taikyti konkrečiam regionui pritaikytas energijos vartojimo efektyvumo strategijas. Be to, tyrime nagrinėjamas mažesnis ventiliatorių ir siurblių suvartojamos energijos kiekis, o tai rodo pasyvaus vėdinimo arba strateginio sistemų išjungimo galimybes siekiant taupyti energiją. Šios išvados suteikia svarbių įžvalgų kuriant įvairioms klimato sąlygoms pritaikytą, tvarią infrastruktūrą.Taip / Ye
Studies on low cement content composites with natural zeolite and waste glass additive
No full textDisertacijoje nagrinėjamas gamtinio ceolito ir stiklo atliekos priedų mišiniu (toliau aktyvių mineralinių priedų (AMP) mišinys) modifikuotas cementinis kompozitas. Kompleksinis AMP mišinio poveikis cemento hidratacijos produktų sudėčiai ir mikrostruktūrai padidina cementinių kompozitų atsparumą agresyvios aplinkos poveikiui, neprarandant mechaninių savybių. AMP mišiniu modifikuotas cementinis kompozitas gali būti naudojamas statiniuose, kurių konstrukcijos eksploatuojamos drėgnoje, chloridais prisotintoje aplinkoje, kurioje vyksta cikliški užšaldymo ir (ar) atšildymo procesai, pasireiškiantys atskirai arba vienu metu, dėl to sustiprėja jų ardomasis poveikis cementinio kompozito struktūrai.
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 bei 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 literatūros apžvalgai ir analizei. Jame nagrinėjama gamtinio ceolito ir malto stiklo poveikis cemento hidratacijai, produktams, poringumui, ilgaamžiškumo ir mechaninėms savybėms. Pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje aprašomos tyrimams naudotų žaliavų charakteristikos, taikyti tyrimų metodai ir įranga, modifikuotų cementinių kompozitų mišinių sudėtys ir bandinių ruošimo technologijos. Pabaigoje suformuluotos skyriaus išvados.
Trečiajame skyriuje pateikiami aktyvių mineralinių priedų ir jų mišinio poveikio tyrimų rezultatai. Ištirtas poveikis cemento hidratacijos eigai, produktams, struktūrai, betono gniuždymo stipriui, vandens įsiskverbimo gyliui veikiant slėgiui, atsparumui cikliškiems užšaldymo ir (ar) atšildymo veiksniams ir chloridų difuzijai, kai aktyvūs priedai naudojami atskirai ir kompleksiškai. Pabaigoje pateikiamos skyriaus išvados. Po trečiojo skyriaus pateikiamos bendrosios išvados.
Disertacijose aprašytų tyrimų rezultatai paskelbti 4-iuose moksliniuose straipsniuose, ir pristatyti 7-iose mokslinėse konferencijose Lietuvoje ir užsienyje.The dissertation analyses a modified cement-based composite containing natural zeolite and waste glass (hereinafter a mixture of active mineral additives (AMA)). The combined effect of AMA on the composition and microstructure of cement hydration products enhances the resistance of cement-based composites to aggressive environments without deteriorating the mechanical properties of the composite. Cement-based composite modified with AMA can be used in structures exposed to humid chloride-laden environments, where freezing/thawing processes occur simultaneously or separately and thus intensify the destructive effect on the structure of cement-based composite.
The doctoral dissertation consists of three chapters, general conclusions, and lists of literature references and the author’s publications on the thesis topic.
The introduction chapter discusses the research topic, and the relevance of the research, describes the object of the research, states the aim and objectives of the research, describes the research methodology, the scientific novelty of the research, the practical value of research results and thesis statements. The introduction chapter ends with a list of the author’s publications and conference presentations on the topic of the doctoral thesis and the structure of the thesis.
The first chapter covers literature review and analysis. It presents the influence of natural zeolite and ground glass on the hydration reaction, hydration products, porosity, durability and mechanical properties of Portland cement. The chapter ends with the formulation of conclusions and specified objectives of the thesis.
The second chapter describes the characteristics of the materials used for the tests, the methods and equipment used, the compositions of the modified cement-based composites and specimen preparation techniques. The chapter ends with conclusions.
The third chapter presents the results of the tests on the effect of mineral additives and their mixture. The effect of mineral additives on the progress of cement hydration, hydration products and their structure, compressive strength of concrete, the depth of water penetration under pressure, resistance to freeze-thaw cycles and chloride diffusion when the active additives are used separately and in combination. The chapter ends with conclusions. The third chapter is followed by general conclusions.
The results of the research covered by the doctoral dissertation were published in four research articles and presented at seven scientific conferences in Lithuania and abroad.Taip / Ye
Time Series Data Augmentation Methods for Deep Learning Models in Conveyor Belt Load Classification
No full textThis work explores time series data augmentation methods for deep learning and their application for conveyor belt tension signals. In this research, conveyor belt load data was collected and analyzed for five different weights: 0.5 kg, 1 kg, 2 kg, 3 kg, and 5 kg. The research includes applying time series data augmentations like Laplace noise, Gaussian noise, uniform noise, magnitude warping, and channel permutation. Furthermore, new conveyor belt tension signals were generated using a Time VAE model. This study investigates the influence of time series augmentation methods on the accuracy of deep learning models. A CNN-LSTM deep learning model capable of classifying conveyor belt signal data has been developed. The biggest positive impact on the classification accuracy was the addition of Laplace noise, which improved the baseline (no augmentation) accuracy by 4.07 % to 98.64 % for 0.8 second signal data.Taip / YesResearch Council of Lithuania (LMTLT)S-PD-22-8
Biblioteka informuoja, 2024 Nr. 3 (647)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.3 (647)202