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Understanding human roles in AI-driven aviation through an evolutionary economics lens
No full textThis study investigates how human roles retain strategic value in AI-driven aviation through an evolutionary
economics lens. Using a mixed-methods approach – combining theoretical analysis, case studies, a Delphi process, and
scenario forecasting – the paper reveals co-evolutionary dynamics where innovation and institutional selection drive
workforce adaptation in aviation. Findings indicate that human roles evolve toward strategic oversight (e.g., ethical
judgment, crisis management) and hybrid skill sets (e.g., AI supervisors, predictive maintenance), with the “AI-augmented
workforce” emerging as the most plausible future in 2040. Key factors in achieving this balance include regulatory
agility, workforce adaptability, and trust-building. The study pioneers the application of evolutionary economics
to AI in aviation, offering a multidisciplinary framework to align technological advancements with socio-institutional
realities. Practical recommendations include adaptive certification processes, hybrid training models, and ethical governance
frameworks, positioning aviation as a model for human-AI collaboration in high-stakes industries.Taip / Ye
Biblioteka informuoja, 2025 Nr. 37 (734)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.37 (734)202
Internet of things technologies: the case of the logistics sector
No full textTechnological change and rapid transformation are very significant in various business areas. The logistics
sector is no exception; one of the fastest-growing technologies in this area is integrating the Internet of Things (IoT)
into certain logistics activity areas. The Internet of Things (IoT) promotes the transformation of processes and leads to
greater operational efficiency, security, and, at the same time, sustainability. The fact that the Internet of Things (IoT),
as a technology and its applicability, is essential in logistics is emphasised by the research conducted and the presentation
of their results in scientific literature and practical discussions. This article presents what Internet of Things (IoT)
solutions are integrated into logistics. A systematic literature and secondary data analysis will be applied to achieve
this goal. The results obtained within the conducted research and analysis limits will imply further possible research
directions.Taip / Ye
Tvari centralizuoto šilumos tiekimo tinklų transformacija: Salininkų atvejo analizė
No full textGlobal climate challenges, driven by rising greenhouse gas emissions and unsustainable energy practices,
demand urgent action to transition toward cleaner and more efficient energy systems. The European Union has set
ambitious targets to combat climate change, promoting renewable energy adoption and efficiency. Lithuania plays a
crucial role in this transition with its cold winters and reliance on centralised heating systems. District Heating Networks
(DHNs), which supply heat to residential and commercial buildings, are vital to achieving energy efficiency
and sustainability in Lithuania’s urban areas. The Salininkai DHN in Vilnius serves 46 buildings, including residential
structures, a kindergarten, a supermarket, and small businesses. Powered by two 4.7 MW gas boilers with 85% efficiency,
the system faces substantial heat losses due to its centralised heating point at one network corner and inefficiencies
in many buildings with F and G energy class ratings and outdated radiator systems. This study evaluates
Salininkai’s energy production and distribution systems to improve efficiency and sustainability. Using EnergyPRO, the
analysis simulates various scenarios, including integrating a 1 MW electric air-to-water heat pump, a 3,000 m³ thermal
storage system, and a solar park to reduce natural gas and commercial electricity dependency. Additionally, it explores
repositioning the heating source to the network’s centre and decentralising the network. The insights gained will guide
recommendations to optimise heat distribution, reduce energy losses, and enhance the network’s sustainability, which
will be vetted by the Primary Energy Factor (PEF). These strategies could position the Salininkai DHN as a model for
similar networks facing comparable challenges worldwide.Globalūs klimato iššūkiai, kylantys dėl didėjančio
šiltnamio efektą sukeliančių dujų kiekio bei netvarių energijos
vartojimo įpročių, skatina skubius veiksmus pereinant prie
švaresnių ir efektyvesnių energijos sistemų. Europos Sąjunga
yra išsikėlusi ambicingus tikslus kovai su klimato kaita, skatindama
atsinaujinančių energijos šaltinių naudojimą ir energijos
vartojimo efektyvumą. Lietuva, pasižyminti šaltomis žiemomis ir priklausomybe nuo centralizuotų šilumos tiekimo sistemų,
šiame kontekste atlieka svarbų vaidmenį. Centralizuoto
šilumos tiekimo tinklai (CŠTT), kurie tiekia šilumą gyvenamiesiems
ir komerciniams pastatams, yra kertiniai elementai
siekiant energinio efektyvumo ir tvarumo Lietuvos miestuose.
Salininkų CŠTT šiuo metu Vilniuje aptarnauja 46 pastatus:
gyvenamuosius namus, vaikų darželį, prekybos centrą
ir mažas įmones. Sistemą sudaro du 4,7 MW galios dujiniai
katilai, kurių naudingumo koeficientas siekia 85 %, tačiau ji
susiduriama su keliais iššūkiais: šilumos šaltinis įrengtas viename
tinklo kampe, dėl to fiksuojami dideli šilumos nuostoliai,
o daugelio pastatų energinio naudingumo klasė yra F arba
G. Be to, naudojamos pasenusios radiatorinės sistemos. Šiame
tyrime vertinama Salininkų energijos gamybos ir paskirstymo
sistema, siekiant padidinti jos efektyvumą ir tvarumą. Naudojant
„EnergyPRO“ programinę įrangą, buvo simuliuoti įvairūs
scenarijai, įskaitant 1 MW galios elektrinio oro-vandens šilumos
siurblio integravimą, 3,000 m³ talpos šilumos akumuliacinę
talpyklą ir saulės parką, siekiant sumažinti priklausomybę
nuo gamtinių dujų ir komercinės elektros energijos. Taip
pat vertinamos galimybės perkelti šilumos šaltinį į tinklo centrą
ir decentralizuoti sistemą. Gautos įžvalgos padės formuluoti
rekomendacijas, kaip optimizuoti šilumos paskirstymą,
sumažinti energijos nuostolius bei padidinti tinklo tvarumą,
atsižvelgiant į pirminės energijos faktorių (PEF). Įgyvendinus
šias strategijas, Salininkų CŠTT galėtų tapti pavyzdys panašiems
tinklams visame pasaulyje.Taip / Ye
Statistical trends of compatibility of family affairs and employment of women in Georgia
No full textAt the modern stage of development, increasing women’s economic activity is becoming increasingly important.
This is confirmed by the trends revealed in the labor market of Georgia, which are formed against the background
of both positive and negative changes in the country according to gender.
The aim of the paper was to outline the main trends of compatibility of family affairs and employment of women in
Georgia against the Background of the growth of theirs labor activity.
Methods of statistical observation, data gathering, grouping, and analysis, corresponding to the stages of statistical research,
were used during the research process. From the methods of analysis, we used averages, time series, correlation,
selective observation methods.
The evolution of society led to the transformation of men’s and women’s thinking in Georgia. Indicators of women’s
activity are increasing, however, it is differentiated according to age groups. The growth rate of women’s earnings is
higher than the growth rate of men’s earnings, but the wage ratio between women and men remains high. The research
showed that the employment of women has a positive impact on the family and its structure. An increase in income
strengthens the family financially and creates additional motivation for the creative and professional growth of women,
as well as for the expansion and development of the family.Taip / Ye
Deep Learning Approach For Weed Detection To Determine Soil Condition
No full textMobile technology has transformed information gathering and accessibility, enabling real-time data collection and analysis through portable devices. Identifying soil conditions is critical in agriculture, yet traditional methods often require specialized tools and can be challenging. The presence of weeds can serve as an initial indicator of soil conditions. This study addresses these challenges by developing a mobile application that utilizes Artificial Intelligence (AI) to determine soil conditions based on weed identification. The application employs YOLOv11, a state-of-the-art object detection model known for its speed, accuracy, and efficiency. YOLOv11's backbone incorporates C3K2 blocks, an evolved CSP bottleneck for efficient feature extraction, while its neck integrates the Spatial Pyramid Pooling Fast (SPFF) module and C2PSA block to enhance spatial attention and focus on critical regions. Data collection and processing were conducted using Google Colab and Roboflow, achieving outstanding performance metrics, including high precision, recall, F1 score, and an impressive 87% mean average precision (mAP). In a comparative analysis of YOLOv11, YOLOv10, and SSD, YOLOv11 stands out with an impressive 87% mean average precision (mAP), demonstrating its superior accuracy in identifying weeds and determining soil conditions. The integration of this model into Android devices allows users to capture weed images and give the soil condition based on the weeds. This application addresses this gap by providing farmers with an efficient and hassle-free solution using artificial intelligence to determine soil conditions based on weeds.Taip / Ye
Optinių linijinių keitiklių charakteristikų gerinimo metodų kūrimas ir tyrimas
No full textOptical linear encoders are crucial for high-precision measurement systems used in industries like CNC machining, semiconductor manufacturing, 3D printing, and robotics. They offer better accuracy and resolution than other technologies, but practical challenges, such as subdivisional error (SDE) and installation errors, limit their performance. These issues affect surface quality and motion precision, especially in applications requiring high precision. Despite the research, existing solutions often fail to address these challenges under real-world conditions, highlighting the need for methods that enhance encoder accuracy and reliability by reducing SDE and improving mounting tolerance.
This research explores new approaches through theoretical modelling and experimental validation. Advanced mask-less lithography technology is used to create custom main gratings with harmonic suppression patterns to reduce odd-order harmonic distortions, a primary cause of SDE. A hybrid-grating design for open-type optical linear encoders is introduced to improve mounting tolerance and stabilize light distribution over a wider installation gap. MATLAB simulations model the light distribution properties, and experimental testing is conducted on a platform replicating industrial conditions to ensure practical relevance.
A key innovation of the dissertation is the hybrid-grating design, which improves mounting tolerance and signal integrity under sub-optimal installation conditions. This design reduces sensitivity to environmental and mechanical disturbances while addressing odd-order harmonic distortions, thus reducing SDE. This dual approach enhances accuracy and ensures reliability in industrial environments. Experimental results show significant SDE reduction and improved signal quality, with the hybrid-grating design maintaining accuracy over a wider installation gap. These results, supported by MATLAB simulations and experimental data, demonstrate the potential benefits for industries requiring high-precision machinery.
SDE reduction and mounting tolerance are addressed to enhance the design and application of optical linear encoders. The proposed innovations enhance the accuracy and reliability of optical linear encoder systems, offering practical solutions scalable for industrial applications. The presented work bridges theoretical modelling and practical implementation, providing valuable references for the next generation of high-precision optical linear encoders.Optiniai linijiniai keitikliai yra labai svarbūs didelio tikslumo matavimo sistemoms, naudojamoms tokiose pramonės šakose kaip CNC apdirbimas, puslaidininkių gamyba, 3D spausdinimas ir robotika. Jie pasižymi geresniu tikslumu ir skiriamąja geba nei kitos technologijos, tačiau praktiniai iššūkiai, tokie kaip dalijamosios vidinio žingsnio paklaidos (angl. Subdivisional error, SDE) ir diegimo klaidos, riboja jų veikimą. Šios problemos turi įtaką paviršiaus kokybei ir judėjimo tikslumui, ypač tais atvejais, kai reikia didelio tikslumo. Nepaisant tyrimų, esami sprendimai dažnai nesugeba išspręsti šių iššūkių realiomis sąlygomis, todėl išryškėja poreikis metodams, galintiems padidinti matavimo tikslumą ir patikimumą, sumažinti SDE bei pagerinti montavimo toleranciją.
Disertacijoje nagrinėjami nauji metodai, taikant teorinį modeliavimą ir eksperimentinį patvirtinimą. Pažangi mask-free (liet. be šablono) litografijos technologija naudojama kuriant pasirinktines pagrindines groteles su harmonikų slopinimo raštais, siekiant sumažinti keistos eilės harmoninius iškraipymus, kurie yra pagrindinė SDE priežastis. Atvirojo tipo optinių linijinių keitiklių hibridinės grotelės pristatomos siekiant pagerinti montavimo toleranciją ir stabilizuoti šviesos pasiskirstymą per platesnį montavimo tarpą. Šviesos paskirstymo savybes modeliuojamos su MATLAB, o eksperimentiniai bandymai atliekami naudojant stendą, atkartojančiame pramonines sąlygas, kad būtų užtikrintas praktinis aktualumas.
Pagrindinė disertacinio darbo naujovė yra hibridinių grotelių dizainas, pagerinantis montavimo toleranciją ir signalo vientisumą esant neoptimalioms įrengimo sąlygoms. Ši konstrukcija sumažina jautrumą aplinkos ir mechaniniams trikdžiams, kartu pašalindama harmoninius iškraipymus, taip sumažindama SDE. Šis dvigubas metodas padidina tikslumą ir užtikrina patikimumą pramoninėje aplinkoje. Eksperimentiniai rezultatai rodo reikšmingą SDE sumažėjimą ir geresnę signalo kokybę, o hibridinės grotelės išlaiko tikslumą per platesnį montavimo tarpą. Šie rezultatai, paremti MATLAB modeliavimu ir eksperimentiniais duomenimis, parodo galimą naudą pramonės šakoms, kurioms reikia didelio tikslumo.
Siekiant pagerinti optinių linijinių keitiklių projektavimą ir taikymą reikia mažinti SDE ir montavimo toleranciją. Siūlomos naujovės padidina šių sistemų tikslumą ir patikimumą ir siūlo praktiškus sprendimus, kuriuos galima pritaikyti pramonėje. Šis darbas sujungia teorinį modeliavimą ir praktinį įgyvendinimą, suteikiant vertingų nuorodų naujos kartos didelio tikslumo optiniams linijiniams keitikliams
Research on the Efficiency of Applying WebGL and D3.js in the Creation of Graphical Elements in Web Applications
No full textWith the rising demand for data visualization in web applications, choosing an efficient tool has become critically important for developers. However, as data volumes grow, challenges related to performance and ensuring seamless interactive user experience arise, complicating the choice of the optimal visualization approach. This study compares two popular technologies—D3.js and WebGL—used for rendering graphical elements. The analysis is based on key criteria, including hardware rendering specifics, performance, community support, extensibility, and limitations. Recommendations are provided regarding the appropriate use of visualization technologies depending on task-specific requirements and application conditions, formulated through a multi-criteria analysis.Taip / Ye
Biblioteka informuoja, 2025 Nr. 26 (723)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.26 (723)202
A Systematic Framework for Resistor Tolerance Analysis to Improve Voltage Stability in Electronic Circuits
No full textIn electronic circuits, ensuring a stable output voltage is crucial, especially when working with voltage dividers. Variations in resistor values due to manufacturing tolerances affected by temperature variations can introduce unexpected fluctuations in output voltage, thereby affecting circuit performance. While selecting higher tolerance resistors reduces costs, it compromises voltage stability, whereas using lower tolerance resistors significantly increases circuit cost. Hence, an optimal balance between cost and performance is essential. In this view, this paper presents a systematic framework for identifying optimal resistor tolerance values that maintain voltage stability within an acceptable range. Python-based simulations are employed to analyze voltage variations by varying resistor values within a ±10% tolerance range, automatically. The results are processed to identify the most suitable resistor configurations. All the practical combinations are tabulated by ranking them based on less voltage deviation and more resistor tolerances. An optimal solution with this desired functionality is given as the highest rank. Besides, visual representations are plotted for better insight. By automating the analysis and visualization, this research provides a practical tool for engineers, industry professionals, researchers, and to optimize voltage divider performance with minimal manual effort. The proposed approach simplifies resistor selection, ensuring both cost-effectiveness and reliable circuit design.Taip / Ye