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Phenomenon of retroeconomics in post-Soviet countries: necroeconomics as the past and the future of retroeconomics
No full textIn Post-pandemic world, after global shutdown and involuntary “break” for the world globalized economic system, the world witnesses the unavoidable changes in the economic processes and in the world economic geography. One of the reasons is the Russia-Ukraine war, which caused serious shifts in global political economy. We are witnessing enormous number of old and not-so-old problems. In all these processes development the term Zombie-economics gets the new life and becomes a new challenge and a problem for the economies worldwide. It demands renewed researches and discussions, aimed to find new approaches in order to overcome the global problem for many countries, as developing, also developed ones. Retroeconomics, together with Necro- and Zombie-economics becomes actual and this topic will be dedicated to the discussion of the ways of overcoming the mentioned problem in contemporary globalized world.Taip / Yes
Lightweight portland cement mixtures with perlite for 3D printing of concrete structures
No full text3D printed concrete is a special type of concrete that can be laid through a 3D printer layer by layer without any formwork support or vibration. Important performance indicators of this concrete: rheology, mechanical properties, durability, can be optimized by choosing various materials. The purpose of this work is to use a mineral additive - perlite - in 3D concrete. In the studies, the pearlite content was up to 11.5%. Rheological tests of modified cement mortars were carried out using a rotary rheometer Rheotest RN 4.1, determining flow curves, ultimate shear stresses and plastic viscosity after mixing and after 60 min. Volumetric coefficient of water separation was calculated, the density and compressive strength were determined. It can be stated that the pearlite additive improves the formability of concrete mixtures using 3D printing technology, reduces the density of concrete, which increases the stability of the concrete mixture and reduces the thermal conductivity of concrete during the exploatation of the product
Evaluation of the efficiency of the ventilation system in an administrative building
No full textEuropai susiduriant su energetine krize, kylant energijos kainoms, vartotojai ieško būdų kaip efektyviau panaudoti energiją ir sumažinti jos sąnaudas. Vienas iš pagrindinių Europos Sąjungos žaliojo kurso tikslų yra siekti statyti ir projektuoti aukštos energinės klasės pastatus su efektyviai veikiančiomis šildymo, vėdinimo ir oro kondicionavimo (ŠVOK) bei pastato valdymo sistemomis. Šiuo metu pastatuose didžiausią energijos dalį suvartoja ŠVOK sistemos ir dažnais atvejais jos suvartoja daugiau energijos nei planuota projektavimo / modeliavimo etape. Tokie atvejai galimi tuomet, kai projektuojant sistemas yra priimtos netinkamos prielaidos, sistemų valdymas nėra tinkamai sureguliuojamas ir apribojamas vartotojams. Straipsnyje analizuojamas realus administracinis pastatas ir remiantis ilgalaikiais stebėjimo rezultatais vertinamas jo vėdinimo sistemų efektyvumas. Išanalizavus patalpų CO2 užterštumo reikšmes stebėjimo laikotarpiu buvo pasiūlytos kelios valdymo priemonės, kurios padėtų sutaupyti energijos.Facing the energy crisis in Europe and the rise in energy prices, consumers are seeking ways to more efficiently use energy and reduce its costs. In the European Union’s green agenda, one of the main goals is to aim at constructing and designing high-energy class buildings with efficiently operating heating, ventilation, and air conditioning (HVAC) and building management systems. Currently, HVAC systems consume the largest portion of energy in buildings, and in many cases, they consume more energy than planned during the design/modeling stage. Such cases occur when incorrect assumptions are made during system design, system management is unregulated, and users are not restricted in system management. The article analyzes a real administrative building and evaluates the efficiency of its ventilation systems based on long-term monitoring results. After analyzing the levels of CO2 pollution in the premises during the monitoring period, several management measures were proposed to help save energy.Taip / Ye
Digital technologies in the context of small and medium-sized enterprises of the manufacturing industry
No full textIn the literature, digitalization is often designated as a so-called megatrend. One of the key characteristics of megatrends is that they are characterized by their ability to influence the environment in a variety of areas. In the case of digital change, this process is powered by digital technologies. Scientific publications from the recent past were examined as part of a literature review with the aim to identify and assess digital technologies and their areas of application in the context of small and medium-sized enterprises (SMEs) from the manufacturing industry. The study highlights that a significant proportion of scientific research in this area focuses on “Industry 4.0” and the associated digital technologies. However, it also became clear that there are different classifications of digital technologies in literature. It has also been shown that there is a wide variety of technologies and devices that are considered as digital technologies in the respective literature sources. Without appropriate sub-categorization, this variety could make it difficult to compare digital technologies in cross-literature studies. Furthermore, the study revealed indications that the interplay of digital technologies appears to be an underrepresented topic in the studies examined. For this reason, this study encourages a more holistic view of the digital technologies used by manufacturing SMEs.Taip / Yes
Biblioteka informuoja, 2024 Nr. 47 (691)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.47 (691)202
Development of tax administration in the conditions of digitalization of the economy
No full textIn the era of digitalization of the economy, tax administration faces new challenges and opportunities. This study aims to analyze current trends in tax administration and identify ways to improve it taking into account the requirements of the digital economy. Based on theoretical analysis and practical examples, the article discusses the main directions and methods of improving the efficiency of tax authorities through the introduction of digital technologies. The study emphasizes the importance of integrating innovative information and communication technologies into the processes of tax administration to ensure its transparency, accessibility and convenience for taxpayers. The results of the work offer recommendations for the formation of an ecosystem of tax administration in the digital economy, contributing to the strengthening of trust between the state and business, as well as improving tax collection and reducing tax risks.Taip / Yes
Application of a machine learning model to improve the efficiency of the ventilation control system in a building
No full textDisertacijoje nagrinėjamos vėdinimo sistemos energijos suvartojimo problemos, kurios tiesiogiai susijusios su vartotojų elgsena.
Pagrindiniai tyrimo objektai – atvirojo tipo biurai ir jų vėdinimo sistemos.
Disertacijos tikslas – sukurti dirbtiniu intelektu grįstą vėdinimo sistemos valdymo modelį vadovaujantis vartotojų elgsenos prognozavimu.
Darbe sprendžiami šie pagrindiniai uždaviniai:
Pirmasis uždavinys – vartotojų elgsenos parametrų identifikavimas ir jų įtakos pastato energijos suvartojimui vertinimas.
Antrasis uždavinys – atlikti realių pastatų ilgalaikę stebėseną, išanalizuoti pastatų užimtumo ir mikroklimato parametrų duomenis ir paruošti duomenų imtį, reikalingą matematiniam prognozavimo modeliui kurti.
Trečiasis uždavinys – adaptuoti mašininiu mokymusi grįstų modelių taikymo galimybes pagal patalpų vartotojų užimtumą ir atlikti modelio validavimą.
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 temos 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. Jame aptariami veiksniai, darantys įtaką vartotojų elgsenai, ir vartotojų elgsenos prognozavimo modeliai.
Antrajame skyriuje aptariami tyrimo objektai ir jų dalyvių elgsena, taip pat pasyviosios vartotojų elgsenos prognozavimo modeliai ir jų integravimo į pastato vėdinimo sistemą veikimo koncepcija.
Trečiajame skyriuje atliekama mašininio mokymosi modelių prognozavimo jautrumo analizė. Pasiūlytas atvirojo tipo biurų vėdinimo sistemos modeliuojantis algoritmas, parodantis sistemos veikimo efektyvumą prog-nozuojant pasyviąją vartotojų elgseną. Kiekvieno skyriaus pabaigoje ir atlikus galutinius tyrimus pateikiamos bendros darbo išvados. Disertacijos pabaigoje yra atskiras skyrius, kuriame pateikiamos benrosios tyrimo išvados.
Disertacijos tema paskelbti šeši straipsniai: du recenzuojamuose mokslo žurnaluose, turinčiuose cituojamumo rodiklį Clarivate Analytics Web of Science duomenų bazėse; vienas tarptautinių konferencijų leidiniuose, referuojamuose Clarivate Analytics Web of Science duomenų bazėje Conference Proceedings, trys kituose recenzuojamuose mokslo žurnaluose. Disertacijoje atliktų tyrimų rezultatai buvo paskelbti dviejose mokslinėse konferencijose Lietuvoje ir užsienyje.This dissertation addresses the energy consumption problems of ventilation systems, which are directly related to user behaviour.
The main objects of the research are open-plan office spaces and their ventilation systems
This dissertation aims to develop an artificial intelligence-based model for ventilation system control based on the prediction of user behaviour.
The dissertation addresses several main challenges: first, to identify user behaviour parameters and assess their impact on building energy consumption; second, to carry out long-term monitoring of real buildings, to analyse data on occupancy and microclimate parameters and to prepare a data sample for the development of a mathematical prediction model; and finally, to adapt to machine learning-based models based on occupancy rates of premises and to validate the model.
The dissertation consists of an introduction, three chapters, general conclusions, a list of literature, and a list of publications on the dissertation’s subject.
The introduction discusses the research problem and the relevance of the work, describes the research object, formulates the aim and objectives of the dissertation, describes the research methodology, the novelty of the topic, the practical significance of the results, and the defended statements. The introduction closes with lists of the author’s publications and conference presentations on the subject of the dissertation and the presented structure of the dissertation.
The First Chapter is devoted to a literature review. It discusses the factors influencing user behaviour and models for predicting user behaviour.
The Second Chapter discusses the research objects and the behaviour of their participants, as well as the methods for predicting passive user behaviour and the concept of how to integrate them into the building ventilation system.
The Third Chapter provides a sensitivity analysis of the prediction of machine learning models. A modelling algorithm for an open-type office ventilation system is proposed to show the performance of the system in predicting passive user behaviour. Each chapter closes with an outline of the general conclusions for the work covered in it. There is a separate chapter, of general conclusions of the research at the end of the dissertation.
Six articles were published on the topic of the dissertation: two in peer-reviewed scientific journals with a citation index in Clarivate Analytics Web of Science databases, one in international conference publications referenced in the Clarivate Analytics Web of Science database Conference Proceedings, and three in other peer-reviewed journals. The results of the research were published in two scientific conferences in Lithuania and abroad.Taip / Ye
The nexus between ESG rating and stock returns: opportunities for investor
No full textNowadays, environmental, social, and governance (ESG) investing gets increased academic attention and a practical spotlight. Companies listed on a stock exchange receive sustainability scores provided by rating agencies. In turn, investors seek not only to get a return in the stock market but also to construct a portfolio of companies that positively affect the economy and society while remaining ethically responsible. But is it possible to obtain sufficient returns, at the same time reaching sustainability objectives? Based on the 2023 year’s data and regression analysis, the research aims to determine the relationship between US stock return and ESG rating, as well as its separate economic, social, and governance components. The research findings demonstrate no significant relationship between stock return and ESG, including its components. The proposed framework for determining ESG and stock return nexus can be useful for individual and institutional investors in forming their investment portfolios.Taip / Yes
An evaluation of the competitiveness of the Slovak automotive industry via digitalization and the adaptability of the population to Industry 4.0
No full textIn this paper, the social effects of rapid digitization in Slovakia are examined. Several data show that the Slovak economy has become less competitive since 2020. Similarly, Slovakia’s preparedness for transformation into a modern and resilient economy is a matter of concern. The methodology investigates insolvency models in Slovakia via descriptive statistics of the secondary data. DESI data illustrates population digitization. Study objectives were compared and synthesized using data and visualization techniques. Graphs indicate that the influence of digitization on production and logistics automation surpasses that on product value. The study highlighted the importance of monitoring and predicting digitization’s effects. Countries being reviewed must understand this and make changes as quickly as possible.Taip / YesIThe use of quantitative methods to assess the impact of the latest crisis on the performance of business entities in V4 countries at the Faculty of Operation and Economics of Transport and Communications, University of Zilina, Slovakia1/KE/202
Towards Human Activity Recognition in Smart Environments through Thermal Imaging
No full textThis paper presents the results of keypoint detection achieved through training YOLOv8 pose models on a thermal person dataset, aiming towards human activity recognition in smart environments. The YOLOv8 pose models, ranging from Nano to Extra Large configurations, were evaluated based on their parameters, Object Keypoint Similarity (OKS) percentage, and processing time per frame. Results indicate that even the smallest model, Nano, achieved a satisfactory OKS of 95.6% with a processing time of 10.4 milliseconds per frame. As model complexity increased, OKS remained high, with a marginal decrease in performance. The findings suggest promising prospects for utilizing thermal imaging in human activity recognition systems, with the potential for real-time deployment in smart environments.Taip / Ye